]> The Tcpdump Group git mirrors - libpcap/commitdiff
Don't use global state for the BPF compiler.
authorGuy Harris <[email protected]>
Thu, 11 Feb 2016 20:05:37 +0000 (12:05 -0800)
committerGuy Harris <[email protected]>
Thu, 11 Feb 2016 20:05:37 +0000 (12:05 -0800)
This allows multiple pcap_compile() calls to be in progress on different
pcap_t's in different threads.

(No, you can't count on that behavior in older versions of libpcap, so
only do that if you know you're using a newer version of libpcap.)

gencode.c
gencode.h
grammar.y
nametoaddr.c
nametoaddr.h
optimize.c
pcap-int.h
pcap-win32.c
scanner.l

index ad1324b09d6270e8be8ce5c9ca01e11129db7d6b..ea641f1d063f105ae4ca6c02fbb85912ddc1300d 100644 (file)
--- a/gencode.c
+++ b/gencode.c
@@ -177,43 +177,22 @@ struct addrinfo {
 
 #define JMP(c) ((c)|BPF_JMP|BPF_K)
 
-/* Locals */
-static jmp_buf top_ctx;
-static pcap_t *bpf_pcap;
-
-/* Hack for handling VLAN and MPLS stacks. */
-#ifdef _WIN32
-static u_int   label_stack_depth = (u_int)-1, vlan_stack_depth = (u_int)-1;
-#else
-static u_int   label_stack_depth = -1U, vlan_stack_depth = -1U;
-#endif
-
-/* XXX */
-static int     pcap_fddipad;
-
-/* VARARGS */
-void
-bpf_error(const char *fmt, ...)
-{
-       va_list ap;
-
-       va_start(ap, fmt);
-       if (bpf_pcap != NULL)
-               (void)pcap_vsnprintf(pcap_geterr(bpf_pcap), PCAP_ERRBUF_SIZE,
-                   fmt, ap);
-       va_end(ap);
-       longjmp(top_ctx, 1);
-       /* NOTREACHED */
+/*
+ * "Push" the current value of the link-layer header type and link-layer
+ * header offset onto a "stack", and set a new value.  (It's not a
+ * full-blown stack; we keep only the top two items.)
+ */
+#define PUSH_LINKHDR(cs, new_linktype, new_is_variable, new_constant_part, new_reg) \
+{ \
+       (cs)->prevlinktype = (cs)->linktype; \
+       (cs)->off_prevlinkhdr = (cs)->off_linkhdr; \
+       (cs)->linktype = (new_linktype); \
+       (cs)->off_linkhdr.is_variable = (new_is_variable); \
+       (cs)->off_linkhdr.constant_part = (new_constant_part); \
+       (cs)->off_linkhdr.reg = (new_reg); \
+       (cs)->is_geneve = 0; \
 }
 
-static void init_linktype(pcap_t *);
-
-static void init_regs(void);
-static int alloc_reg(void);
-static void free_reg(int);
-
-static struct block *root;
-
 /*
  * Absolute offsets, which are offsets from the beginning of the raw
  * packet data, are, in the general case, the sum of a variable value
@@ -254,17 +233,6 @@ enum e_offrel {
        OR_TRAN_IPV6            /* transport-layer header, with IPv6 network layer */
 };
 
-#ifdef INET6
-/*
- * As errors are handled by a longjmp, anything allocated must be freed
- * in the longjmp handler, so it must be reachable from that handler.
- * One thing that's allocated is the result of pcap_nametoaddrinfo();
- * it must be freed with freeaddrinfo().  This variable points to any
- * addrinfo structure that would need to be freed.
- */
-static struct addrinfo *ai;
-#endif
-
 /*
  * We divy out chunks of memory rather than call malloc each time so
  * we don't have to worry about leaking memory.  It's probably
@@ -280,94 +248,318 @@ struct chunk {
        void *m;
 };
 
-static struct chunk chunks[NCHUNKS];
-static int cur_chunk;
+/* Code generator state */
+
+struct _compiler_state {
+       jmp_buf top_ctx;
+       pcap_t *bpf_pcap;
+
+       struct icode ic;
+
+       int snaplen;
+
+       int linktype;
+       int prevlinktype;
+       int outermostlinktype;
 
-static void *newchunk(size_t);
-static void freechunks(void);
-static inline struct block *new_block(int);
-static inline struct slist *new_stmt(int);
-static struct block *gen_retblk(int);
-static inline void syntax(void);
+       bpf_u_int32 netmask;
+       int no_optimize;
+
+       /* Hack for handling VLAN and MPLS stacks. */
+       u_int label_stack_depth;
+       u_int vlan_stack_depth;
+
+       /* XXX */
+       int pcap_fddipad;
+
+#ifdef INET6
+       /*
+        * As errors are handled by a longjmp, anything allocated must
+        * be freed in the longjmp handler, so it must be reachable
+        * from that handler.
+        *
+        * One thing that's allocated is the result of pcap_nametoaddrinfo();
+        * it must be freed with freeaddrinfo().  This variable points to
+        * any addrinfo structure that would need to be freed.
+        */
+       struct addrinfo *ai;
+#endif
+
+       /*
+        * Various code constructs need to know the layout of the packet.
+        * These values give the necessary offsets from the beginning
+        * of the packet data.
+        */
+
+       /*
+        * Absolute offset of the beginning of the link-layer header.
+        */
+       bpf_abs_offset off_linkhdr;
+
+       /*
+        * If we're checking a link-layer header for a packet encapsulated
+        * in another protocol layer, this is the equivalent information
+        * for the previous layers' link-layer header from the beginning
+        * of the raw packet data.
+        */
+       bpf_abs_offset off_prevlinkhdr;
+
+       /*
+        * This is the equivalent information for the outermost layers'
+        * link-layer header.
+        */
+       bpf_abs_offset off_outermostlinkhdr;
+
+       /*
+        * Absolute offset of the beginning of the link-layer payload.
+        */
+       bpf_abs_offset off_linkpl;
+
+       /*
+        * "off_linktype" is the offset to information in the link-layer
+        * header giving the packet type. This is an absolute offset
+        * from the beginning of the packet.
+        *
+        * For Ethernet, it's the offset of the Ethernet type field; this
+        * means that it must have a value that skips VLAN tags.
+        *
+        * For link-layer types that always use 802.2 headers, it's the
+        * offset of the LLC header; this means that it must have a value
+        * that skips VLAN tags.
+        *
+        * For PPP, it's the offset of the PPP type field.
+        *
+        * For Cisco HDLC, it's the offset of the CHDLC type field.
+        *
+        * For BSD loopback, it's the offset of the AF_ value.
+        *
+        * For Linux cooked sockets, it's the offset of the type field.
+        *
+        * off_linktype.constant_part is set to -1 for no encapsulation,
+        * in which case, IP is assumed.
+        */
+       bpf_abs_offset off_linktype;
+
+       /*
+        * TRUE if the link layer includes an ATM pseudo-header.
+        */
+       int is_atm;
+
+       /*
+        * TRUE if "geneve" appeared in the filter; it causes us to
+        * generate code that checks for a Geneve header and assume
+        * that later filters apply to the encapsulated payload.
+        */
+       int is_geneve;
+
+       /*
+        * These are offsets for the ATM pseudo-header.
+        */
+       u_int off_vpi;
+       u_int off_vci;
+       u_int off_proto;
+
+       /*
+        * These are offsets for the MTP2 fields.
+        */
+       u_int off_li;
+       u_int off_li_hsl;
+
+       /*
+        * These are offsets for the MTP3 fields.
+        */
+       u_int off_sio;
+       u_int off_opc;
+       u_int off_dpc;
+       u_int off_sls;
+
+       /*
+        * This is the offset of the first byte after the ATM pseudo_header,
+        * or -1 if there is no ATM pseudo-header.
+        */
+       u_int off_payload;
+
+       /*
+        * These are offsets to the beginning of the network-layer header.
+        * They are relative to the beginning of the link-layer payload
+        * (i.e., they don't include off_linkhdr.constant_part or
+        * off_linkpl.constant_part).
+        *
+        * If the link layer never uses 802.2 LLC:
+        *
+        *      "off_nl" and "off_nl_nosnap" are the same.
+        *
+        * If the link layer always uses 802.2 LLC:
+        *
+        *      "off_nl" is the offset if there's a SNAP header following
+        *      the 802.2 header;
+        *
+        *      "off_nl_nosnap" is the offset if there's no SNAP header.
+        *
+        * If the link layer is Ethernet:
+        *
+        *      "off_nl" is the offset if the packet is an Ethernet II packet
+        *      (we assume no 802.3+802.2+SNAP);
+        *
+        *      "off_nl_nosnap" is the offset if the packet is an 802.3 packet
+        *      with an 802.2 header following it.
+        */
+       u_int off_nl;
+       u_int off_nl_nosnap;
+
+       /*
+        * Here we handle simple allocation of the scratch registers.
+        * If too many registers are alloc'd, the allocator punts.
+        */
+       int regused[BPF_MEMWORDS];
+       int curreg;
+
+       /*
+        * Memory chunks.
+        */
+       struct chunk chunks[NCHUNKS];
+       int cur_chunk;
+};
+
+void
+bpf_syntax_error(compiler_state_t *cstate, const char *msg)
+{
+       bpf_error(cstate, "syntax error in filter expression: %s", msg);
+       /* NOTREACHED */
+}
+
+/* VARARGS */
+void
+bpf_error(compiler_state_t *cstate, const char *fmt, ...)
+{
+       va_list ap;
+
+       va_start(ap, fmt);
+       if (cstate->bpf_pcap != NULL)
+               (void)pcap_vsnprintf(pcap_geterr(cstate->bpf_pcap),
+                   PCAP_ERRBUF_SIZE, fmt, ap);
+       va_end(ap);
+       longjmp(cstate->top_ctx, 1);
+       /* NOTREACHED */
+}
+
+static void init_linktype(compiler_state_t *, pcap_t *);
+
+static void init_regs(compiler_state_t *);
+static int alloc_reg(compiler_state_t *);
+static void free_reg(compiler_state_t *, int);
+
+static void initchunks(compiler_state_t *cstate);
+static void *newchunk(compiler_state_t *cstate, size_t);
+static void freechunks(compiler_state_t *cstate);
+static inline struct block *new_block(compiler_state_t *cstate, int);
+static inline struct slist *new_stmt(compiler_state_t *cstate, int);
+static struct block *gen_retblk(compiler_state_t *cstate, int);
+static inline void syntax(compiler_state_t *cstate);
 
 static void backpatch(struct block *, struct block *);
 static void merge(struct block *, struct block *);
-static struct block *gen_cmp(enum e_offrel, u_int, u_int, bpf_int32);
-static struct block *gen_cmp_gt(enum e_offrel, u_int, u_int, bpf_int32);
-static struct block *gen_cmp_ge(enum e_offrel, u_int, u_int, bpf_int32);
-static struct block *gen_cmp_lt(enum e_offrel, u_int, u_int, bpf_int32);
-static struct block *gen_cmp_le(enum e_offrel, u_int, u_int, bpf_int32);
-static struct block *gen_mcmp(enum e_offrel, u_int, u_int, bpf_int32,
-    bpf_u_int32);
-static struct block *gen_bcmp(enum e_offrel, u_int, u_int, const u_char *);
-static struct block *gen_ncmp(enum e_offrel, bpf_u_int32, bpf_u_int32,
-    bpf_u_int32, bpf_u_int32, int, bpf_int32);
-static struct slist *gen_load_absoffsetrel(bpf_abs_offset *, u_int, u_int);
-static struct slist *gen_load_a(enum e_offrel, u_int, u_int);
-static struct slist *gen_loadx_iphdrlen(void);
-static struct block *gen_uncond(int);
-static inline struct block *gen_true(void);
-static inline struct block *gen_false(void);
-static struct block *gen_ether_linktype(int);
-static struct block *gen_ipnet_linktype(int);
-static struct block *gen_linux_sll_linktype(int);
-static struct slist *gen_load_prism_llprefixlen(void);
-static struct slist *gen_load_avs_llprefixlen(void);
-static struct slist *gen_load_radiotap_llprefixlen(void);
-static struct slist *gen_load_ppi_llprefixlen(void);
-static void insert_compute_vloffsets(struct block *);
-static struct slist *gen_abs_offset_varpart(bpf_abs_offset *);
+static struct block *gen_cmp(compiler_state_t *, enum e_offrel, u_int,
+    u_int, bpf_int32);
+static struct block *gen_cmp_gt(compiler_state_t *, enum e_offrel, u_int,
+    u_int, bpf_int32);
+static struct block *gen_cmp_ge(compiler_state_t *, enum e_offrel, u_int,
+    u_int, bpf_int32);
+static struct block *gen_cmp_lt(compiler_state_t *, enum e_offrel, u_int,
+    u_int, bpf_int32);
+static struct block *gen_cmp_le(compiler_state_t *, enum e_offrel, u_int,
+    u_int, bpf_int32);
+static struct block *gen_mcmp(compiler_state_t *, enum e_offrel, u_int,
+    u_int, bpf_int32, bpf_u_int32);
+static struct block *gen_bcmp(compiler_state_t *, enum e_offrel, u_int,
+    u_int, const u_char *);
+static struct block *gen_ncmp(compiler_state_t *, enum e_offrel, bpf_u_int32,
+    bpf_u_int32, bpf_u_int32, bpf_u_int32, int, bpf_int32);
+static struct slist *gen_load_absoffsetrel(compiler_state_t *, bpf_abs_offset *,
+    u_int, u_int);
+static struct slist *gen_load_a(compiler_state_t *, enum e_offrel, u_int,
+    u_int);
+static struct slist *gen_loadx_iphdrlen(compiler_state_t *);
+static struct block *gen_uncond(compiler_state_t *, int);
+static inline struct block *gen_true(compiler_state_t *);
+static inline struct block *gen_false(compiler_state_t *);
+static struct block *gen_ether_linktype(compiler_state_t *, int);
+static struct block *gen_ipnet_linktype(compiler_state_t *, int);
+static struct block *gen_linux_sll_linktype(compiler_state_t *, int);
+static struct slist *gen_load_prism_llprefixlen(compiler_state_t *);
+static struct slist *gen_load_avs_llprefixlen(compiler_state_t *);
+static struct slist *gen_load_radiotap_llprefixlen(compiler_state_t *);
+static struct slist *gen_load_ppi_llprefixlen(compiler_state_t *);
+static void insert_compute_vloffsets(compiler_state_t *, struct block *);
+static struct slist *gen_abs_offset_varpart(compiler_state_t *,
+    bpf_abs_offset *);
 static int ethertype_to_ppptype(int);
-static struct block *gen_linktype(int);
-static struct block *gen_snap(bpf_u_int32, bpf_u_int32);
-static struct block *gen_llc_linktype(int);
-static struct block *gen_hostop(bpf_u_int32, bpf_u_int32, int, int, u_int, u_int);
+static struct block *gen_linktype(compiler_state_t *, int);
+static struct block *gen_snap(compiler_state_t *, bpf_u_int32, bpf_u_int32);
+static struct block *gen_llc_linktype(compiler_state_t *, int);
+static struct block *gen_hostop(compiler_state_t *, bpf_u_int32, bpf_u_int32,
+    int, int, u_int, u_int);
 #ifdef INET6
-static struct block *gen_hostop6(struct in6_addr *, struct in6_addr *, int, int, u_int, u_int);
+static struct block *gen_hostop6(compiler_state_t *, struct in6_addr *,
+    struct in6_addr *, int, int, u_int, u_int);
 #endif
-static struct block *gen_ahostop(const u_char *, int);
-static struct block *gen_ehostop(const u_char *, int);
-static struct block *gen_fhostop(const u_char *, int);
-static struct block *gen_thostop(const u_char *, int);
-static struct block *gen_wlanhostop(const u_char *, int);
-static struct block *gen_ipfchostop(const u_char *, int);
-static struct block *gen_dnhostop(bpf_u_int32, int);
-static struct block *gen_mpls_linktype(int);
-static struct block *gen_host(bpf_u_int32, bpf_u_int32, int, int, int);
+static struct block *gen_ahostop(compiler_state_t *, const u_char *, int);
+static struct block *gen_ehostop(compiler_state_t *, const u_char *, int);
+static struct block *gen_fhostop(compiler_state_t *, const u_char *, int);
+static struct block *gen_thostop(compiler_state_t *, const u_char *, int);
+static struct block *gen_wlanhostop(compiler_state_t *, const u_char *, int);
+static struct block *gen_ipfchostop(compiler_state_t *, const u_char *, int);
+static struct block *gen_dnhostop(compiler_state_t *, bpf_u_int32, int);
+static struct block *gen_mpls_linktype(compiler_state_t *, int);
+static struct block *gen_host(compiler_state_t *, bpf_u_int32, bpf_u_int32,
+    int, int, int);
 #ifdef INET6
-static struct block *gen_host6(struct in6_addr *, struct in6_addr *, int, int, int);
+static struct block *gen_host6(compiler_state_t *, struct in6_addr *,
+    struct in6_addr *, int, int, int);
 #endif
 #ifndef INET6
 static struct block *gen_gateway(const u_char *, bpf_u_int32 **, int, int);
 #endif
-static struct block *gen_ipfrag(void);
-static struct block *gen_portatom(int, bpf_int32);
-static struct block *gen_portrangeatom(int, bpf_int32, bpf_int32);
-static struct block *gen_portatom6(int, bpf_int32);
-static struct block *gen_portrangeatom6(int, bpf_int32, bpf_int32);
-struct block *gen_portop(int, int, int);
-static struct block *gen_port(int, int, int);
-struct block *gen_portrangeop(int, int, int, int);
-static struct block *gen_portrange(int, int, int, int);
-struct block *gen_portop6(int, int, int);
-static struct block *gen_port6(int, int, int);
-struct block *gen_portrangeop6(int, int, int, int);
-static struct block *gen_portrange6(int, int, int, int);
-static int lookup_proto(const char *, int);
-static struct block *gen_protochain(int, int, int);
-static struct block *gen_proto(int, int, int);
-static struct slist *xfer_to_x(struct arth *);
-static struct slist *xfer_to_a(struct arth *);
-static struct block *gen_mac_multicast(int);
-static struct block *gen_len(int, int);
-static struct block *gen_check_802_11_data_frame(void);
-static struct block *gen_geneve_ll_check(void);
-
-static struct block *gen_ppi_dlt_check(void);
-static struct block *gen_msg_abbrev(int type);
+static struct block *gen_ipfrag(compiler_state_t *);
+static struct block *gen_portatom(compiler_state_t *, int, bpf_int32);
+static struct block *gen_portrangeatom(compiler_state_t *, int, bpf_int32,
+    bpf_int32);
+static struct block *gen_portatom6(compiler_state_t *, int, bpf_int32);
+static struct block *gen_portrangeatom6(compiler_state_t *, int, bpf_int32,
+    bpf_int32);
+struct block *gen_portop(compiler_state_t *, int, int, int);
+static struct block *gen_port(compiler_state_t *, int, int, int);
+struct block *gen_portrangeop(compiler_state_t *, int, int, int, int);
+static struct block *gen_portrange(compiler_state_t *, int, int, int, int);
+struct block *gen_portop6(compiler_state_t *, int, int, int);
+static struct block *gen_port6(compiler_state_t *, int, int, int);
+struct block *gen_portrangeop6(compiler_state_t *, int, int, int, int);
+static struct block *gen_portrange6(compiler_state_t *, int, int, int, int);
+static int lookup_proto(compiler_state_t *, const char *, int);
+static struct block *gen_protochain(compiler_state_t *, int, int, int);
+static struct block *gen_proto(compiler_state_t *, int, int, int);
+static struct slist *xfer_to_x(compiler_state_t *, struct arth *);
+static struct slist *xfer_to_a(compiler_state_t *, struct arth *);
+static struct block *gen_mac_multicast(compiler_state_t *, int);
+static struct block *gen_len(compiler_state_t *, int, int);
+static struct block *gen_check_802_11_data_frame(compiler_state_t *);
+static struct block *gen_geneve_ll_check(compiler_state_t *cstate);
+
+static struct block *gen_ppi_dlt_check(compiler_state_t *);
+static struct block *gen_msg_abbrev(compiler_state_t *, int type);
+
+static void
+initchunks(compiler_state_t *cstate)
+{
+       int i;
+
+       for (i = 0; i < NCHUNKS; i++)
+               cstate->chunks[i].m = NULL;
+       cstate->cur_chunk = 0;
+}
 
 static void *
-newchunk(size_t n)
+newchunk(compiler_state_t *cstate, size_t n)
 {
        struct chunk *cp;
        int k;
@@ -381,58 +573,53 @@ newchunk(size_t n)
        n = ALIGN(n);
 #endif
 
-       cp = &chunks[cur_chunk];
+       cp = &cstate->chunks[cstate->cur_chunk];
        if (n > cp->n_left) {
-               ++cp, k = ++cur_chunk;
+               ++cp, k = ++cstate->cur_chunk;
                if (k >= NCHUNKS)
-                       bpf_error("out of memory");
+                       bpf_error(cstate, "out of memory");
                size = CHUNK0SIZE << k;
                cp->m = (void *)malloc(size);
                if (cp->m == NULL)
-                       bpf_error("out of memory");
+                       bpf_error(cstate, "out of memory");
                memset((char *)cp->m, 0, size);
                cp->n_left = size;
                if (n > size)
-                       bpf_error("out of memory");
+                       bpf_error(cstate, "out of memory");
        }
        cp->n_left -= n;
        return (void *)((char *)cp->m + cp->n_left);
 }
 
 static void
-freechunks()
+freechunks(compiler_state_t *cstate)
 {
        int i;
 
-       cur_chunk = 0;
        for (i = 0; i < NCHUNKS; ++i)
-               if (chunks[i].m != NULL) {
-                       free(chunks[i].m);
-                       chunks[i].m = NULL;
-               }
+               if (cstate->chunks[i].m != NULL)
+                       free(cstate->chunks[i].m);
 }
 
 /*
  * A strdup whose allocations are freed after code generation is over.
  */
 char *
-sdup(s)
-       register const char *s;
+sdup(compiler_state_t *cstate, const char *s)
 {
        size_t n = strlen(s) + 1;
-       char *cp = newchunk(n);
+       char *cp = newchunk(cstate, n);
 
        strlcpy(cp, s, n);
        return (cp);
 }
 
 static inline struct block *
-new_block(code)
-       int code;
+new_block(compiler_state_t *cstate, int code)
 {
        struct block *p;
 
-       p = (struct block *)newchunk(sizeof(*p));
+       p = (struct block *)newchunk(cstate, sizeof(*p));
        p->s.code = code;
        p->head = p;
 
@@ -440,42 +627,36 @@ new_block(code)
 }
 
 static inline struct slist *
-new_stmt(code)
-       int code;
+new_stmt(compiler_state_t *cstate, int code)
 {
        struct slist *p;
 
-       p = (struct slist *)newchunk(sizeof(*p));
+       p = (struct slist *)newchunk(cstate, sizeof(*p));
        p->s.code = code;
 
        return p;
 }
 
 static struct block *
-gen_retblk(v)
-       int v;
+gen_retblk(compiler_state_t *cstate, int v)
 {
-       struct block *b = new_block(BPF_RET|BPF_K);
+       struct block *b = new_block(cstate, BPF_RET|BPF_K);
 
        b->s.k = v;
        return b;
 }
 
 static inline void
-syntax()
+syntax(compiler_state_t *cstate)
 {
-       bpf_error("syntax error in filter expression");
+       bpf_error(cstate, "syntax error in filter expression");
 }
 
-static bpf_u_int32 netmask;
-static int snaplen;
-int no_optimize;
-
 int
 pcap_compile(pcap_t *p, struct bpf_program *program,
             const char *buf, int optimize, bpf_u_int32 mask)
 {
-       extern int n_errors;
+       compiler_state_t cstate;
        const char * volatile xbuf = buf;
        yyscan_t scanner = NULL;
        YY_BUFFER_STATE in_buffer = NULL;
@@ -493,7 +674,6 @@ pcap_compile(pcap_t *p, struct bpf_program *program,
        if (!done)
                pcap_wsockinit();
        done = 1;
-       EnterCriticalSection(&g_PcapCompileCriticalSection);
 #endif
 
        /*
@@ -506,27 +686,27 @@ pcap_compile(pcap_t *p, struct bpf_program *program,
                rc = -1;
                goto quit;
        }
-       no_optimize = 0;
-       n_errors = 0;
-       root = NULL;
-       bpf_pcap = p;
-       init_regs();
-
-       if (setjmp(top_ctx)) {
+       initchunks(&cstate);
+       cstate.no_optimize = 0;
+       cstate.ai = NULL;
+       cstate.ic.root = NULL;
+       cstate.ic.cur_mark = 0;
+       cstate.bpf_pcap = p;
+       init_regs(&cstate);
+
+       if (setjmp(cstate.top_ctx)) {
 #ifdef INET6
-               if (ai != NULL) {
-                       freeaddrinfo(ai);
-                       ai = NULL;
-               }
+               if (cstate.ai != NULL)
+                       freeaddrinfo(cstate.ai);
 #endif
                rc = -1;
                goto quit;
        }
 
-       netmask = mask;
+       cstate.netmask = mask;
 
-       snaplen = pcap_snapshot(p);
-       if (snaplen == 0) {
+       cstate.snaplen = pcap_snapshot(p);
+       if (cstate.snaplen == 0) {
                pcap_snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
                         "snaplen of 0 rejects all packets");
                rc = -1;
@@ -534,24 +714,28 @@ pcap_compile(pcap_t *p, struct bpf_program *program,
        }
 
        if (pcap_lex_init(&scanner) != 0)
-               bpf_error("can't initialize scanner: %s", pcap_strerror(errno));
+               bpf_error(&cstate, "can't initialize scanner: %s", pcap_strerror(errno));
        in_buffer = pcap__scan_string(xbuf ? xbuf : "", scanner);
-       init_linktype(p);
-       (void)pcap_parse(scanner);
 
-       if (n_errors)
-               syntax();
+       /*
+        * Associate the compiler state with the lexical analyzer
+        * state.
+        */
+       pcap_set_extra(&cstate, scanner);
 
-       if (root == NULL)
-               root = gen_retblk(snaplen);
+       init_linktype(&cstate, p);
+       (void)pcap_parse(scanner, &cstate);
 
-       if (optimize && !no_optimize) {
-               bpf_optimize(&root);
-               if (root == NULL ||
-                   (root->s.code == (BPF_RET|BPF_K) && root->s.k == 0))
-                       bpf_error("expression rejects all packets");
+       if (cstate.ic.root == NULL)
+               cstate.ic.root = gen_retblk(&cstate, cstate.snaplen);
+
+       if (optimize && !cstate.no_optimize) {
+               bpf_optimize(&cstate, &cstate.ic);
+               if (cstate.ic.root == NULL ||
+                   (cstate.ic.root->s.code == (BPF_RET|BPF_K) && cstate.ic.root->s.k == 0))
+                       bpf_error(&cstate, "expression rejects all packets");
        }
-       program->bf_insns = icode_to_fcode(root, &len);
+       program->bf_insns = icode_to_fcode(&cstate, &cstate.ic, cstate.ic.root, &len);
        program->bf_len = len;
 
        rc = 0;  /* We're all okay */
@@ -568,11 +752,7 @@ quit:
        /*
         * Clean up our own allocated memory.
         */
-       freechunks();
-
-#ifdef _WIN32
-       LeaveCriticalSection(&g_PcapCompileCriticalSection);
-#endif
+       freechunks(&cstate);
 
        return (rc);
 }
@@ -654,8 +834,7 @@ merge(b0, b1)
 }
 
 void
-finish_parse(p)
-       struct block *p;
+finish_parse(compiler_state_t *cstate, struct block *p)
 {
        struct block *ppi_dlt_check;
 
@@ -678,7 +857,7 @@ finish_parse(p)
         * for tests that fail early, and it's not clear that's
         * worth the effort.
         */
-       insert_compute_vloffsets(p->head);
+       insert_compute_vloffsets(cstate, p->head);
 
        /*
         * For DLT_PPI captures, generate a check of the per-packet
@@ -693,14 +872,14 @@ finish_parse(p)
         * 802.11 code (*and* anything else for which PPI is used)
         * and choose between them early in the BPF program?
         */
-       ppi_dlt_check = gen_ppi_dlt_check();
+       ppi_dlt_check = gen_ppi_dlt_check(cstate);
        if (ppi_dlt_check != NULL)
                gen_and(ppi_dlt_check, p);
 
-       backpatch(p, gen_retblk(snaplen));
+       backpatch(p, gen_retblk(cstate, cstate->snaplen));
        p->sense = !p->sense;
-       backpatch(p, gen_retblk(0));
-       root = p->head;
+       backpatch(p, gen_retblk(cstate, 0));
+       cstate->ic.root = p->head;
 }
 
 void
@@ -734,65 +913,50 @@ gen_not(b)
 }
 
 static struct block *
-gen_cmp(offrel, offset, size, v)
-       enum e_offrel offrel;
-       u_int offset, size;
-       bpf_int32 v;
+gen_cmp(compiler_state_t *cstate, enum e_offrel offrel, u_int offset,
+    u_int size, bpf_int32 v)
 {
-       return gen_ncmp(offrel, offset, size, 0xffffffff, BPF_JEQ, 0, v);
+       return gen_ncmp(cstate, offrel, offset, size, 0xffffffff, BPF_JEQ, 0, v);
 }
 
 static struct block *
-gen_cmp_gt(offrel, offset, size, v)
-       enum e_offrel offrel;
-       u_int offset, size;
-       bpf_int32 v;
+gen_cmp_gt(compiler_state_t *cstate, enum e_offrel offrel, u_int offset,
+    u_int size, bpf_int32 v)
 {
-       return gen_ncmp(offrel, offset, size, 0xffffffff, BPF_JGT, 0, v);
+       return gen_ncmp(cstate, offrel, offset, size, 0xffffffff, BPF_JGT, 0, v);
 }
 
 static struct block *
-gen_cmp_ge(offrel, offset, size, v)
-       enum e_offrel offrel;
-       u_int offset, size;
-       bpf_int32 v;
+gen_cmp_ge(compiler_state_t *cstate, enum e_offrel offrel, u_int offset,
+    u_int size, bpf_int32 v)
 {
-       return gen_ncmp(offrel, offset, size, 0xffffffff, BPF_JGE, 0, v);
+       return gen_ncmp(cstate, offrel, offset, size, 0xffffffff, BPF_JGE, 0, v);
 }
 
 static struct block *
-gen_cmp_lt(offrel, offset, size, v)
-       enum e_offrel offrel;
-       u_int offset, size;
-       bpf_int32 v;
+gen_cmp_lt(compiler_state_t *cstate, enum e_offrel offrel, u_int offset,
+    u_int size, bpf_int32 v)
 {
-       return gen_ncmp(offrel, offset, size, 0xffffffff, BPF_JGE, 1, v);
+       return gen_ncmp(cstate, offrel, offset, size, 0xffffffff, BPF_JGE, 1, v);
 }
 
 static struct block *
-gen_cmp_le(offrel, offset, size, v)
-       enum e_offrel offrel;
-       u_int offset, size;
-       bpf_int32 v;
+gen_cmp_le(compiler_state_t *cstate, enum e_offrel offrel, u_int offset,
+    u_int size, bpf_int32 v)
 {
-       return gen_ncmp(offrel, offset, size, 0xffffffff, BPF_JGT, 1, v);
+       return gen_ncmp(cstate, offrel, offset, size, 0xffffffff, BPF_JGT, 1, v);
 }
 
 static struct block *
-gen_mcmp(offrel, offset, size, v, mask)
-       enum e_offrel offrel;
-       u_int offset, size;
-       bpf_int32 v;
-       bpf_u_int32 mask;
+gen_mcmp(compiler_state_t *cstate, enum e_offrel offrel, u_int offset,
+    u_int size, bpf_int32 v, bpf_u_int32 mask)
 {
-       return gen_ncmp(offrel, offset, size, mask, BPF_JEQ, 0, v);
+       return gen_ncmp(cstate, offrel, offset, size, mask, BPF_JEQ, 0, v);
 }
 
 static struct block *
-gen_bcmp(offrel, offset, size, v)
-       enum e_offrel offrel;
-       register u_int offset, size;
-       register const u_char *v;
+gen_bcmp(compiler_state_t *cstate, enum e_offrel offrel, u_int offset,
+    u_int size, const u_char *v)
 {
        register struct block *b, *tmp;
 
@@ -802,7 +966,7 @@ gen_bcmp(offrel, offset, size, v)
                bpf_int32 w = ((bpf_int32)p[0] << 24) |
                    ((bpf_int32)p[1] << 16) | ((bpf_int32)p[2] << 8) | p[3];
 
-               tmp = gen_cmp(offrel, offset + size - 4, BPF_W, w);
+               tmp = gen_cmp(cstate, offrel, offset + size - 4, BPF_W, w);
                if (b != NULL)
                        gen_and(b, tmp);
                b = tmp;
@@ -812,14 +976,14 @@ gen_bcmp(offrel, offset, size, v)
                register const u_char *p = &v[size - 2];
                bpf_int32 w = ((bpf_int32)p[0] << 8) | p[1];
 
-               tmp = gen_cmp(offrel, offset + size - 2, BPF_H, w);
+               tmp = gen_cmp(cstate, offrel, offset + size - 2, BPF_H, w);
                if (b != NULL)
                        gen_and(b, tmp);
                b = tmp;
                size -= 2;
        }
        if (size > 0) {
-               tmp = gen_cmp(offrel, offset, BPF_B, (bpf_int32)v[0]);
+               tmp = gen_cmp(cstate, offrel, offset, BPF_B, (bpf_int32)v[0]);
                if (b != NULL)
                        gen_and(b, tmp);
                b = tmp;
@@ -834,24 +998,22 @@ gen_bcmp(offrel, offset, size, v)
  * should test the opposite of "jtype".
  */
 static struct block *
-gen_ncmp(offrel, offset, size, mask, jtype, reverse, v)
-       enum e_offrel offrel;
-       bpf_int32 v;
-       bpf_u_int32 offset, size, mask, jtype;
-       int reverse;
+gen_ncmp(compiler_state_t *cstate, enum e_offrel offrel, bpf_u_int32 offset,
+    bpf_u_int32 size, bpf_u_int32 mask, bpf_u_int32 jtype, int reverse,
+    bpf_int32 v)
 {
        struct slist *s, *s2;
        struct block *b;
 
-       s = gen_load_a(offrel, offset, size);
+       s = gen_load_a(cstate, offrel, offset, size);
 
        if (mask != 0xffffffff) {
-               s2 = new_stmt(BPF_ALU|BPF_AND|BPF_K);
+               s2 = new_stmt(cstate, BPF_ALU|BPF_AND|BPF_K);
                s2->s.k = mask;
                sappend(s, s2);
        }
 
-       b = new_block(JMP(jtype));
+       b = new_block(cstate, JMP(jtype));
        b->stmts = s;
        b->s.k = v;
        if (reverse && (jtype == BPF_JGT || jtype == BPF_JGE))
@@ -859,230 +1021,88 @@ gen_ncmp(offrel, offset, size, mask, jtype, reverse, v)
        return b;
 }
 
-/*
- * Various code constructs need to know the layout of the packet.
- * These variables give the necessary offsets from the beginning
- * of the packet data.
- */
-
-/*
- * Absolute offset of the beginning of the link-layer header.
- */
-static bpf_abs_offset off_linkhdr;
-
-/*
- * If we're checking a link-layer header for a packet encapsulated in
- * another protocol layer, this is the equivalent information for the
- * previous layers' link-layer header from the beginning of the raw
- * packet data.
- */
-static bpf_abs_offset off_prevlinkhdr;
-
-/*
- * This is the equivalent information for the outermost layers' link-layer
- * header.
- */
-static bpf_abs_offset off_outermostlinkhdr;
-
-/*
- * "Push" the current value of the link-layer header type and link-layer
- * header offset onto a "stack", and set a new value.  (It's not a
- * full-blown stack; we keep only the top two items.)
- */
-#define PUSH_LINKHDR(new_linktype, new_is_variable, new_constant_part, new_reg) \
-{ \
-       prevlinktype = new_linktype; \
-       off_prevlinkhdr = off_linkhdr; \
-       linktype = new_linktype; \
-       off_linkhdr.is_variable = new_is_variable; \
-       off_linkhdr.constant_part = new_constant_part; \
-       off_linkhdr.reg = new_reg; \
-       is_geneve = 0; \
-}
-
-/*
- * Absolute offset of the beginning of the link-layer payload.
- */
-static bpf_abs_offset off_linkpl;
-
-/*
- * "off_linktype" is the offset to information in the link-layer header
- * giving the packet type. This is an absolute offset from the beginning
- * of the packet.
- *
- * For Ethernet, it's the offset of the Ethernet type field; this
- * means that it must have a value that skips VLAN tags.
- *
- * For link-layer types that always use 802.2 headers, it's the
- * offset of the LLC header; this means that it must have a value
- * that skips VLAN tags.
- *
- * For PPP, it's the offset of the PPP type field.
- *
- * For Cisco HDLC, it's the offset of the CHDLC type field.
- *
- * For BSD loopback, it's the offset of the AF_ value.
- *
- * For Linux cooked sockets, it's the offset of the type field.
- *
- * off_linktype.constant_part is set to -1 for no encapsulation,
- * in which case, IP is assumed.
- */
-static bpf_abs_offset off_linktype;
-
-/*
- * TRUE if the link layer includes an ATM pseudo-header.
- */
-static int is_atm = 0;
-
-/*
- * TRUE if "geneve" appeared in the filter; it causes us to generate
- * code that checks for a Geneve header and assume that later filters
- * apply to the encapsulated payload.
- */
-static int is_geneve = 0;
-
-/*
- * These are offsets for the ATM pseudo-header.
- */
-static u_int off_vpi;
-static u_int off_vci;
-static u_int off_proto;
-
-/*
- * These are offsets for the MTP2 fields.
- */
-static u_int off_li;
-static u_int off_li_hsl;
-
-/*
- * These are offsets for the MTP3 fields.
- */
-static u_int off_sio;
-static u_int off_opc;
-static u_int off_dpc;
-static u_int off_sls;
-
-/*
- * This is the offset of the first byte after the ATM pseudo_header,
- * or -1 if there is no ATM pseudo-header.
- */
-static u_int off_payload;
-
-/*
- * These are offsets to the beginning of the network-layer header.
- * They are relative to the beginning of the link-layer payload (i.e.,
- * they don't include off_linkhdr.constant_part or off_linkpl.constant_part).
- *
- * If the link layer never uses 802.2 LLC:
- *
- *     "off_nl" and "off_nl_nosnap" are the same.
- *
- * If the link layer always uses 802.2 LLC:
- *
- *     "off_nl" is the offset if there's a SNAP header following
- *     the 802.2 header;
- *
- *     "off_nl_nosnap" is the offset if there's no SNAP header.
- *
- * If the link layer is Ethernet:
- *
- *     "off_nl" is the offset if the packet is an Ethernet II packet
- *     (we assume no 802.3+802.2+SNAP);
- *
- *     "off_nl_nosnap" is the offset if the packet is an 802.3 packet
- *     with an 802.2 header following it.
- */
-static u_int off_nl;
-static u_int off_nl_nosnap;
-
-static int linktype;
-static int prevlinktype;
-static int outermostlinktype;
-
 static void
-init_linktype(p)
-       pcap_t *p;
+init_linktype(compiler_state_t *cstate, pcap_t *p)
 {
-       pcap_fddipad = p->fddipad;
+       cstate->pcap_fddipad = p->fddipad;
 
        /*
         * We start out with only one link-layer header.
         */
-       outermostlinktype = pcap_datalink(p);
-       off_outermostlinkhdr.constant_part = 0;
-       off_outermostlinkhdr.is_variable = 0;
-       off_outermostlinkhdr.reg = -1;
+       cstate->outermostlinktype = pcap_datalink(p);
+       cstate->off_outermostlinkhdr.constant_part = 0;
+       cstate->off_outermostlinkhdr.is_variable = 0;
+       cstate->off_outermostlinkhdr.reg = -1;
 
-       prevlinktype = outermostlinktype;
-       off_prevlinkhdr.constant_part = 0;
-       off_prevlinkhdr.is_variable = 0;
-       off_prevlinkhdr.reg = -1;
+       cstate->prevlinktype = cstate->outermostlinktype;
+       cstate->off_prevlinkhdr.constant_part = 0;
+       cstate->off_prevlinkhdr.is_variable = 0;
+       cstate->off_prevlinkhdr.reg = -1;
 
-       linktype = outermostlinktype;
-       off_linkhdr.constant_part = 0;
-       off_linkhdr.is_variable = 0;
-       off_linkhdr.reg = -1;
+       cstate->linktype = cstate->outermostlinktype;
+       cstate->off_linkhdr.constant_part = 0;
+       cstate->off_linkhdr.is_variable = 0;
+       cstate->off_linkhdr.reg = -1;
 
        /*
         * XXX
         */
-       off_linkpl.constant_part = 0;
-       off_linkpl.is_variable = 0;
-       off_linkpl.reg = -1;
+       cstate->off_linkpl.constant_part = 0;
+       cstate->off_linkpl.is_variable = 0;
+       cstate->off_linkpl.reg = -1;
 
-       off_linktype.constant_part = 0;
-       off_linktype.is_variable = 0;
-       off_linktype.reg = -1;
+       cstate->off_linktype.constant_part = 0;
+       cstate->off_linktype.is_variable = 0;
+       cstate->off_linktype.reg = -1;
 
        /*
         * Assume it's not raw ATM with a pseudo-header, for now.
         */
-       is_atm = 0;
-       off_vpi = -1;
-       off_vci = -1;
-       off_proto = -1;
-       off_payload = -1;
+       cstate->is_atm = 0;
+       cstate->off_vpi = -1;
+       cstate->off_vci = -1;
+       cstate->off_proto = -1;
+       cstate->off_payload = -1;
 
        /*
         * And not Geneve.
         */
-       is_geneve = 0;
+       cstate->is_geneve = 0;
 
        /*
         * And assume we're not doing SS7.
         */
-       off_li = -1;
-       off_li_hsl = -1;
-       off_sio = -1;
-       off_opc = -1;
-       off_dpc = -1;
-       off_sls = -1;
+       cstate->off_li = -1;
+       cstate->off_li_hsl = -1;
+       cstate->off_sio = -1;
+       cstate->off_opc = -1;
+       cstate->off_dpc = -1;
+       cstate->off_sls = -1;
 
-        label_stack_depth = 0;
-        vlan_stack_depth = 0;
+       cstate->label_stack_depth = 0;
+       cstate->vlan_stack_depth = 0;
 
-       switch (linktype) {
+       switch (cstate->linktype) {
 
        case DLT_ARCNET:
-               off_linktype.constant_part = 2;
-               off_linkpl.constant_part = 6;
-               off_nl = 0;             /* XXX in reality, variable! */
-               off_nl_nosnap = 0;      /* no 802.2 LLC */
+               cstate->off_linktype.constant_part = 2;
+               cstate->off_linkpl.constant_part = 6;
+               cstate->off_nl = 0;     /* XXX in reality, variable! */
+               cstate->off_nl_nosnap = 0;      /* no 802.2 LLC */
                break;
 
        case DLT_ARCNET_LINUX:
-               off_linktype.constant_part = 4;
-               off_linkpl.constant_part = 8;
-               off_nl = 0;             /* XXX in reality, variable! */
-               off_nl_nosnap = 0;      /* no 802.2 LLC */
+               cstate->off_linktype.constant_part = 4;
+               cstate->off_linkpl.constant_part = 8;
+               cstate->off_nl = 0;             /* XXX in reality, variable! */
+               cstate->off_nl_nosnap = 0;      /* no 802.2 LLC */
                break;
 
        case DLT_EN10MB:
-               off_linktype.constant_part = 12;
-               off_linkpl.constant_part = 14;  /* Ethernet header length */
-               off_nl = 0;             /* Ethernet II */
-               off_nl_nosnap = 3;      /* 802.3+802.2 */
+               cstate->off_linktype.constant_part = 12;
+               cstate->off_linkpl.constant_part = 14;  /* Ethernet header length */
+               cstate->off_nl = 0;             /* Ethernet II */
+               cstate->off_nl_nosnap = 3;      /* 802.3+802.2 */
                break;
 
        case DLT_SLIP:
@@ -1090,44 +1110,44 @@ init_linktype(p)
                 * SLIP doesn't have a link level type.  The 16 byte
                 * header is hacked into our SLIP driver.
                 */
-               off_linktype.constant_part = -1;
-               off_linkpl.constant_part = 16;
-               off_nl = 0;
-               off_nl_nosnap = 0;      /* no 802.2 LLC */
+               cstate->off_linktype.constant_part = -1;
+               cstate->off_linkpl.constant_part = 16;
+               cstate->off_nl = 0;
+               cstate->off_nl_nosnap = 0;      /* no 802.2 LLC */
                break;
 
        case DLT_SLIP_BSDOS:
                /* XXX this may be the same as the DLT_PPP_BSDOS case */
-               off_linktype.constant_part = -1;
+               cstate->off_linktype.constant_part = -1;
                /* XXX end */
-               off_linkpl.constant_part = 24;
-               off_nl = 0;
-               off_nl_nosnap = 0;      /* no 802.2 LLC */
+               cstate->off_linkpl.constant_part = 24;
+               cstate->off_nl = 0;
+               cstate->off_nl_nosnap = 0;      /* no 802.2 LLC */
                break;
 
        case DLT_NULL:
        case DLT_LOOP:
-               off_linktype.constant_part = 0;
-               off_linkpl.constant_part = 4;
-               off_nl = 0;
-               off_nl_nosnap = 0;      /* no 802.2 LLC */
+               cstate->off_linktype.constant_part = 0;
+               cstate->off_linkpl.constant_part = 4;
+               cstate->off_nl = 0;
+               cstate->off_nl_nosnap = 0;      /* no 802.2 LLC */
                break;
 
        case DLT_ENC:
-               off_linktype.constant_part = 0;
-               off_linkpl.constant_part = 12;
-               off_nl = 0;
-               off_nl_nosnap = 0;      /* no 802.2 LLC */
+               cstate->off_linktype.constant_part = 0;
+               cstate->off_linkpl.constant_part = 12;
+               cstate->off_nl = 0;
+               cstate->off_nl_nosnap = 0;      /* no 802.2 LLC */
                break;
 
        case DLT_PPP:
        case DLT_PPP_PPPD:
        case DLT_C_HDLC:                /* BSD/OS Cisco HDLC */
        case DLT_PPP_SERIAL:            /* NetBSD sync/async serial PPP */
-               off_linktype.constant_part = 2; /* skip HDLC-like framing */
-               off_linkpl.constant_part = 4;   /* skip HDLC-like framing and protocol field */
-               off_nl = 0;
-               off_nl_nosnap = 0;      /* no 802.2 LLC */
+               cstate->off_linktype.constant_part = 2; /* skip HDLC-like framing */
+               cstate->off_linkpl.constant_part = 4;   /* skip HDLC-like framing and protocol field */
+               cstate->off_nl = 0;
+               cstate->off_nl_nosnap = 0;      /* no 802.2 LLC */
                break;
 
        case DLT_PPP_ETHER:
@@ -1135,17 +1155,17 @@ init_linktype(p)
                 * This does no include the Ethernet header, and
                 * only covers session state.
                 */
-               off_linktype.constant_part = 6;
-               off_linkpl.constant_part = 8;
-               off_nl = 0;
-               off_nl_nosnap = 0;      /* no 802.2 LLC */
+               cstate->off_linktype.constant_part = 6;
+               cstate->off_linkpl.constant_part = 8;
+               cstate->off_nl = 0;
+               cstate->off_nl_nosnap = 0;      /* no 802.2 LLC */
                break;
 
        case DLT_PPP_BSDOS:
-               off_linktype.constant_part = 5;
-               off_linkpl.constant_part = 24;
-               off_nl = 0;
-               off_nl_nosnap = 0;      /* no 802.2 LLC */
+               cstate->off_linktype.constant_part = 5;
+               cstate->off_linkpl.constant_part = 24;
+               cstate->off_nl = 0;
+               cstate->off_nl_nosnap = 0;      /* no 802.2 LLC */
                break;
 
        case DLT_FDDI:
@@ -1157,12 +1177,12 @@ init_linktype(p)
                 * is being used and pick out the encapsulated Ethernet type.
                 * XXX - should we generate code to check for SNAP?
                 */
-               off_linktype.constant_part = 13;
-               off_linktype.constant_part += pcap_fddipad;
-               off_linkpl.constant_part = 13;  /* FDDI MAC header length */
-               off_linkpl.constant_part += pcap_fddipad;
-               off_nl = 8;             /* 802.2+SNAP */
-               off_nl_nosnap = 3;      /* 802.2 */
+               cstate->off_linktype.constant_part = 13;
+               cstate->off_linktype.constant_part += cstate->pcap_fddipad;
+               cstate->off_linkpl.constant_part = 13;  /* FDDI MAC header length */
+               cstate->off_linkpl.constant_part += cstate->pcap_fddipad;
+               cstate->off_nl = 8;             /* 802.2+SNAP */
+               cstate->off_nl_nosnap = 3;      /* 802.2 */
                break;
 
        case DLT_IEEE802:
@@ -1189,16 +1209,16 @@ init_linktype(p)
                 * the 16-bit value at an offset of 14 (shifted right
                 * 8 - figure out which byte that is).
                 */
-               off_linktype.constant_part = 14;
-               off_linkpl.constant_part = 14;  /* Token Ring MAC header length */
-               off_nl = 8;             /* 802.2+SNAP */
-               off_nl_nosnap = 3;      /* 802.2 */
+               cstate->off_linktype.constant_part = 14;
+               cstate->off_linkpl.constant_part = 14;  /* Token Ring MAC header length */
+               cstate->off_nl = 8;             /* 802.2+SNAP */
+               cstate->off_nl_nosnap = 3;      /* 802.2 */
                break;
 
        case DLT_PRISM_HEADER:
        case DLT_IEEE802_11_RADIO_AVS:
        case DLT_IEEE802_11_RADIO:
-               off_linkhdr.is_variable = 1;
+               cstate->off_linkhdr.is_variable = 1;
                /* Fall through, 802.11 doesn't have a variable link
                 * prefix but is otherwise the same. */
 
@@ -1221,11 +1241,11 @@ init_linktype(p)
                 * header or an AVS header, so, in practice, it's
                 * variable-length.
                 */
-               off_linktype.constant_part = 24;
-               off_linkpl.constant_part = 0;   /* link-layer header is variable-length */
-               off_linkpl.is_variable = 1;
-               off_nl = 8;             /* 802.2+SNAP */
-               off_nl_nosnap = 3;      /* 802.2 */
+               cstate->off_linktype.constant_part = 24;
+               cstate->off_linkpl.constant_part = 0;   /* link-layer header is variable-length */
+               cstate->off_linkpl.is_variable = 1;
+               cstate->off_nl = 8;             /* 802.2+SNAP */
+               cstate->off_nl_nosnap = 3;      /* 802.2 */
                break;
 
        case DLT_PPI:
@@ -1238,12 +1258,12 @@ init_linktype(p)
                 * the encapsulated DLT should be DLT_IEEE802_11) we
                 * generate code to check for this too.
                 */
-               off_linktype.constant_part = 24;
-               off_linkpl.constant_part = 0;   /* link-layer header is variable-length */
-               off_linkpl.is_variable = 1;
-               off_linkhdr.is_variable = 1;
-               off_nl = 8;             /* 802.2+SNAP */
-               off_nl_nosnap = 3;      /* 802.2 */
+               cstate->off_linktype.constant_part = 24;
+               cstate->off_linkpl.constant_part = 0;   /* link-layer header is variable-length */
+               cstate->off_linkpl.is_variable = 1;
+               cstate->off_linkhdr.is_variable = 1;
+               cstate->off_nl = 8;             /* 802.2+SNAP */
+               cstate->off_nl_nosnap = 3;      /* 802.2 */
                break;
 
        case DLT_ATM_RFC1483:
@@ -1259,10 +1279,10 @@ init_linktype(p)
                 * or "pppoa and tcp port 80" and have it check for
                 * PPPo{A,E} and a PPP protocol of IP and....
                 */
-               off_linktype.constant_part = 0;
-               off_linkpl.constant_part = 0;   /* packet begins with LLC header */
-               off_nl = 8;             /* 802.2+SNAP */
-               off_nl_nosnap = 3;      /* 802.2 */
+               cstate->off_linktype.constant_part = 0;
+               cstate->off_linkpl.constant_part = 0;   /* packet begins with LLC header */
+               cstate->off_nl = 8;             /* 802.2+SNAP */
+               cstate->off_nl_nosnap = 3;      /* 802.2 */
                break;
 
        case DLT_SUNATM:
@@ -1270,31 +1290,31 @@ init_linktype(p)
                 * Full Frontal ATM; you get AALn PDUs with an ATM
                 * pseudo-header.
                 */
-               is_atm = 1;
-               off_vpi = SUNATM_VPI_POS;
-               off_vci = SUNATM_VCI_POS;
-               off_proto = PROTO_POS;
-               off_payload = SUNATM_PKT_BEGIN_POS;
-               off_linktype.constant_part = off_payload;
-               off_linkpl.constant_part = off_payload; /* if LLC-encapsulated */
-               off_nl = 8;             /* 802.2+SNAP */
-               off_nl_nosnap = 3;      /* 802.2 */
+               cstate->is_atm = 1;
+               cstate->off_vpi = SUNATM_VPI_POS;
+               cstate->off_vci = SUNATM_VCI_POS;
+               cstate->off_proto = PROTO_POS;
+               cstate->off_payload = SUNATM_PKT_BEGIN_POS;
+               cstate->off_linktype.constant_part = cstate->off_payload;
+               cstate->off_linkpl.constant_part = cstate->off_payload; /* if LLC-encapsulated */
+               cstate->off_nl = 8;             /* 802.2+SNAP */
+               cstate->off_nl_nosnap = 3;      /* 802.2 */
                break;
 
        case DLT_RAW:
        case DLT_IPV4:
        case DLT_IPV6:
-               off_linktype.constant_part = -1;
-               off_linkpl.constant_part = 0;
-               off_nl = 0;
-               off_nl_nosnap = 0;      /* no 802.2 LLC */
+               cstate->off_linktype.constant_part = -1;
+               cstate->off_linkpl.constant_part = 0;
+               cstate->off_nl = 0;
+               cstate->off_nl_nosnap = 0;      /* no 802.2 LLC */
                break;
 
        case DLT_LINUX_SLL:     /* fake header for Linux cooked socket */
-               off_linktype.constant_part = 14;
-               off_linkpl.constant_part = 16;
-               off_nl = 0;
-               off_nl_nosnap = 0;      /* no 802.2 LLC */
+               cstate->off_linktype.constant_part = 14;
+               cstate->off_linkpl.constant_part = 16;
+               cstate->off_nl = 0;
+               cstate->off_nl_nosnap = 0;      /* no 802.2 LLC */
                break;
 
        case DLT_LTALK:
@@ -1303,10 +1323,10 @@ init_linktype(p)
                 * but really it just indicates whether there is a "short" or
                 * "long" DDP packet following.
                 */
-               off_linktype.constant_part = -1;
-               off_linkpl.constant_part = 0;
-               off_nl = 0;
-               off_nl_nosnap = 0;      /* no 802.2 LLC */
+               cstate->off_linktype.constant_part = -1;
+               cstate->off_linkpl.constant_part = 0;
+               cstate->off_nl = 0;
+               cstate->off_nl_nosnap = 0;      /* no 802.2 LLC */
                break;
 
        case DLT_IP_OVER_FC:
@@ -1320,10 +1340,10 @@ init_linktype(p)
                 * XXX - should we generate code to check for SNAP? RFC
                 * 2625 says SNAP should be used.
                 */
-               off_linktype.constant_part = 16;
-               off_linkpl.constant_part = 16;
-               off_nl = 8;             /* 802.2+SNAP */
-               off_nl_nosnap = 3;      /* 802.2 */
+               cstate->off_linktype.constant_part = 16;
+               cstate->off_linkpl.constant_part = 16;
+               cstate->off_nl = 8;             /* 802.2+SNAP */
+               cstate->off_nl_nosnap = 3;      /* 802.2 */
                break;
 
        case DLT_FRELAY:
@@ -1331,10 +1351,10 @@ init_linktype(p)
                 * XXX - we should set this to handle SNAP-encapsulated
                 * frames (NLPID of 0x80).
                 */
-               off_linktype.constant_part = -1;
-               off_linkpl.constant_part = 0;
-               off_nl = 0;
-               off_nl_nosnap = 0;      /* no 802.2 LLC */
+               cstate->off_linktype.constant_part = -1;
+               cstate->off_linkpl.constant_part = 0;
+               cstate->off_nl = 0;
+               cstate->off_nl_nosnap = 0;      /* no 802.2 LLC */
                break;
 
                 /*
@@ -1343,32 +1363,32 @@ init_linktype(p)
                  * so lets start with offset 4 for now and increments later on (FIXME);
                  */
        case DLT_MFR:
-               off_linktype.constant_part = -1;
-               off_linkpl.constant_part = 0;
-               off_nl = 4;
-               off_nl_nosnap = 0;      /* XXX - for now -> no 802.2 LLC */
+               cstate->off_linktype.constant_part = -1;
+               cstate->off_linkpl.constant_part = 0;
+               cstate->off_nl = 4;
+               cstate->off_nl_nosnap = 0;      /* XXX - for now -> no 802.2 LLC */
                break;
 
        case DLT_APPLE_IP_OVER_IEEE1394:
-               off_linktype.constant_part = 16;
-               off_linkpl.constant_part = 18;
-               off_nl = 0;
-               off_nl_nosnap = 0;      /* no 802.2 LLC */
+               cstate->off_linktype.constant_part = 16;
+               cstate->off_linkpl.constant_part = 18;
+               cstate->off_nl = 0;
+               cstate->off_nl_nosnap = 0;      /* no 802.2 LLC */
                break;
 
        case DLT_SYMANTEC_FIREWALL:
-               off_linktype.constant_part = 6;
-               off_linkpl.constant_part = 44;
-               off_nl = 0;             /* Ethernet II */
-               off_nl_nosnap = 0;      /* XXX - what does it do with 802.3 packets? */
+               cstate->off_linktype.constant_part = 6;
+               cstate->off_linkpl.constant_part = 44;
+               cstate->off_nl = 0;             /* Ethernet II */
+               cstate->off_nl_nosnap = 0;      /* XXX - what does it do with 802.3 packets? */
                break;
 
 #ifdef HAVE_NET_PFVAR_H
        case DLT_PFLOG:
-               off_linktype.constant_part = 0;
-               off_linkpl.constant_part = PFLOG_HDRLEN;
-               off_nl = 0;
-               off_nl_nosnap = 0;      /* no 802.2 LLC */
+               cstate->off_linktype.constant_part = 0;
+               cstate->off_linkpl.constant_part = PFLOG_HDRLEN;
+               cstate->off_nl = 0;
+               cstate->off_nl_nosnap = 0;      /* no 802.2 LLC */
                break;
 #endif
 
@@ -1378,186 +1398,186 @@ init_linktype(p)
         case DLT_JUNIPER_PPP:
         case DLT_JUNIPER_CHDLC:
         case DLT_JUNIPER_FRELAY:
-                off_linktype.constant_part = 4;
-               off_linkpl.constant_part = 4;
-               off_nl = 0;
-               off_nl_nosnap = -1;     /* no 802.2 LLC */
+               cstate->off_linktype.constant_part = 4;
+               cstate->off_linkpl.constant_part = 4;
+               cstate->off_nl = 0;
+               cstate->off_nl_nosnap = -1;     /* no 802.2 LLC */
                 break;
 
        case DLT_JUNIPER_ATM1:
-               off_linktype.constant_part = 4;         /* in reality variable between 4-8 */
-               off_linkpl.constant_part = 4;   /* in reality variable between 4-8 */
-               off_nl = 0;
-               off_nl_nosnap = 10;
+               cstate->off_linktype.constant_part = 4;         /* in reality variable between 4-8 */
+               cstate->off_linkpl.constant_part = 4;   /* in reality variable between 4-8 */
+               cstate->off_nl = 0;
+               cstate->off_nl_nosnap = 10;
                break;
 
        case DLT_JUNIPER_ATM2:
-               off_linktype.constant_part = 8;         /* in reality variable between 8-12 */
-               off_linkpl.constant_part = 8;   /* in reality variable between 8-12 */
-               off_nl = 0;
-               off_nl_nosnap = 10;
+               cstate->off_linktype.constant_part = 8;         /* in reality variable between 8-12 */
+               cstate->off_linkpl.constant_part = 8;   /* in reality variable between 8-12 */
+               cstate->off_nl = 0;
+               cstate->off_nl_nosnap = 10;
                break;
 
                /* frames captured on a Juniper PPPoE service PIC
                 * contain raw ethernet frames */
        case DLT_JUNIPER_PPPOE:
         case DLT_JUNIPER_ETHER:
-               off_linkpl.constant_part = 14;
-               off_linktype.constant_part = 16;
-               off_nl = 18;            /* Ethernet II */
-               off_nl_nosnap = 21;     /* 802.3+802.2 */
+               cstate->off_linkpl.constant_part = 14;
+               cstate->off_linktype.constant_part = 16;
+               cstate->off_nl = 18;            /* Ethernet II */
+               cstate->off_nl_nosnap = 21;     /* 802.3+802.2 */
                break;
 
        case DLT_JUNIPER_PPPOE_ATM:
-               off_linktype.constant_part = 4;
-               off_linkpl.constant_part = 6;
-               off_nl = 0;
-               off_nl_nosnap = -1;     /* no 802.2 LLC */
+               cstate->off_linktype.constant_part = 4;
+               cstate->off_linkpl.constant_part = 6;
+               cstate->off_nl = 0;
+               cstate->off_nl_nosnap = -1;     /* no 802.2 LLC */
                break;
 
        case DLT_JUNIPER_GGSN:
-               off_linktype.constant_part = 6;
-               off_linkpl.constant_part = 12;
-               off_nl = 0;
-               off_nl_nosnap = -1;     /* no 802.2 LLC */
+               cstate->off_linktype.constant_part = 6;
+               cstate->off_linkpl.constant_part = 12;
+               cstate->off_nl = 0;
+               cstate->off_nl_nosnap = -1;     /* no 802.2 LLC */
                break;
 
        case DLT_JUNIPER_ES:
-               off_linktype.constant_part = 6;
-               off_linkpl.constant_part = -1;  /* not really a network layer but raw IP addresses */
-               off_nl = -1;            /* not really a network layer but raw IP addresses */
-               off_nl_nosnap = -1;     /* no 802.2 LLC */
+               cstate->off_linktype.constant_part = 6;
+               cstate->off_linkpl.constant_part = -1;  /* not really a network layer but raw IP addresses */
+               cstate->off_nl = -1;            /* not really a network layer but raw IP addresses */
+               cstate->off_nl_nosnap = -1;     /* no 802.2 LLC */
                break;
 
        case DLT_JUNIPER_MONITOR:
-               off_linktype.constant_part = 12;
-               off_linkpl.constant_part = 12;
-               off_nl = 0;             /* raw IP/IP6 header */
-               off_nl_nosnap = -1;     /* no 802.2 LLC */
+               cstate->off_linktype.constant_part = 12;
+               cstate->off_linkpl.constant_part = 12;
+               cstate->off_nl = 0;             /* raw IP/IP6 header */
+               cstate->off_nl_nosnap = -1;     /* no 802.2 LLC */
                break;
 
        case DLT_BACNET_MS_TP:
-               off_linktype.constant_part = -1;
-               off_linkpl.constant_part = -1;
-               off_nl = -1;
-               off_nl_nosnap = -1;
+               cstate->off_linktype.constant_part = -1;
+               cstate->off_linkpl.constant_part = -1;
+               cstate->off_nl = -1;
+               cstate->off_nl_nosnap = -1;
                break;
 
        case DLT_JUNIPER_SERVICES:
-               off_linktype.constant_part = 12;
-               off_linkpl.constant_part = -1;  /* L3 proto location dep. on cookie type */
-               off_nl = -1;            /* L3 proto location dep. on cookie type */
-               off_nl_nosnap = -1;     /* no 802.2 LLC */
+               cstate->off_linktype.constant_part = 12;
+               cstate->off_linkpl.constant_part = -1;  /* L3 proto location dep. on cookie type */
+               cstate->off_nl = -1;            /* L3 proto location dep. on cookie type */
+               cstate->off_nl_nosnap = -1;     /* no 802.2 LLC */
                break;
 
        case DLT_JUNIPER_VP:
-               off_linktype.constant_part = 18;
-               off_linkpl.constant_part = -1;
-               off_nl = -1;
-               off_nl_nosnap = -1;
+               cstate->off_linktype.constant_part = 18;
+               cstate->off_linkpl.constant_part = -1;
+               cstate->off_nl = -1;
+               cstate->off_nl_nosnap = -1;
                break;
 
        case DLT_JUNIPER_ST:
-               off_linktype.constant_part = 18;
-               off_linkpl.constant_part = -1;
-               off_nl = -1;
-               off_nl_nosnap = -1;
+               cstate->off_linktype.constant_part = 18;
+               cstate->off_linkpl.constant_part = -1;
+               cstate->off_nl = -1;
+               cstate->off_nl_nosnap = -1;
                break;
 
        case DLT_JUNIPER_ISM:
-               off_linktype.constant_part = 8;
-               off_linkpl.constant_part = -1;
-               off_nl = -1;
-               off_nl_nosnap = -1;
+               cstate->off_linktype.constant_part = 8;
+               cstate->off_linkpl.constant_part = -1;
+               cstate->off_nl = -1;
+               cstate->off_nl_nosnap = -1;
                break;
 
        case DLT_JUNIPER_VS:
        case DLT_JUNIPER_SRX_E2E:
        case DLT_JUNIPER_FIBRECHANNEL:
        case DLT_JUNIPER_ATM_CEMIC:
-               off_linktype.constant_part = 8;
-               off_linkpl.constant_part = -1;
-               off_nl = -1;
-               off_nl_nosnap = -1;
+               cstate->off_linktype.constant_part = 8;
+               cstate->off_linkpl.constant_part = -1;
+               cstate->off_nl = -1;
+               cstate->off_nl_nosnap = -1;
                break;
 
        case DLT_MTP2:
-               off_li = 2;
-               off_li_hsl = 4;
-               off_sio = 3;
-               off_opc = 4;
-               off_dpc = 4;
-               off_sls = 7;
-               off_linktype.constant_part = -1;
-               off_linkpl.constant_part = -1;
-               off_nl = -1;
-               off_nl_nosnap = -1;
+               cstate->off_li = 2;
+               cstate->off_li_hsl = 4;
+               cstate->off_sio = 3;
+               cstate->off_opc = 4;
+               cstate->off_dpc = 4;
+               cstate->off_sls = 7;
+               cstate->off_linktype.constant_part = -1;
+               cstate->off_linkpl.constant_part = -1;
+               cstate->off_nl = -1;
+               cstate->off_nl_nosnap = -1;
                break;
 
        case DLT_MTP2_WITH_PHDR:
-               off_li = 6;
-               off_li_hsl = 8;
-               off_sio = 7;
-               off_opc = 8;
-               off_dpc = 8;
-               off_sls = 11;
-               off_linktype.constant_part = -1;
-               off_linkpl.constant_part = -1;
-               off_nl = -1;
-               off_nl_nosnap = -1;
+               cstate->off_li = 6;
+               cstate->off_li_hsl = 8;
+               cstate->off_sio = 7;
+               cstate->off_opc = 8;
+               cstate->off_dpc = 8;
+               cstate->off_sls = 11;
+               cstate->off_linktype.constant_part = -1;
+               cstate->off_linkpl.constant_part = -1;
+               cstate->off_nl = -1;
+               cstate->off_nl_nosnap = -1;
                break;
 
        case DLT_ERF:
-               off_li = 22;
-               off_li_hsl = 24;
-               off_sio = 23;
-               off_opc = 24;
-               off_dpc = 24;
-               off_sls = 27;
-               off_linktype.constant_part = -1;
-               off_linkpl.constant_part = -1;
-               off_nl = -1;
-               off_nl_nosnap = -1;
+               cstate->off_li = 22;
+               cstate->off_li_hsl = 24;
+               cstate->off_sio = 23;
+               cstate->off_opc = 24;
+               cstate->off_dpc = 24;
+               cstate->off_sls = 27;
+               cstate->off_linktype.constant_part = -1;
+               cstate->off_linkpl.constant_part = -1;
+               cstate->off_nl = -1;
+               cstate->off_nl_nosnap = -1;
                break;
 
        case DLT_PFSYNC:
-               off_linktype.constant_part = -1;
-               off_linkpl.constant_part = 4;
-               off_nl = 0;
-               off_nl_nosnap = 0;
+               cstate->off_linktype.constant_part = -1;
+               cstate->off_linkpl.constant_part = 4;
+               cstate->off_nl = 0;
+               cstate->off_nl_nosnap = 0;
                break;
 
        case DLT_AX25_KISS:
                /*
                 * Currently, only raw "link[N:M]" filtering is supported.
                 */
-               off_linktype.constant_part = -1;        /* variable, min 15, max 71 steps of 7 */
-               off_linkpl.constant_part = -1;
-               off_nl = -1;            /* variable, min 16, max 71 steps of 7 */
-               off_nl_nosnap = -1;     /* no 802.2 LLC */
+               cstate->off_linktype.constant_part = -1;        /* variable, min 15, max 71 steps of 7 */
+               cstate->off_linkpl.constant_part = -1;
+               cstate->off_nl = -1;            /* variable, min 16, max 71 steps of 7 */
+               cstate->off_nl_nosnap = -1;     /* no 802.2 LLC */
                break;
 
        case DLT_IPNET:
-               off_linktype.constant_part = 1;
-               off_linkpl.constant_part = 24;  /* ipnet header length */
-               off_nl = 0;
-               off_nl_nosnap = -1;
+               cstate->off_linktype.constant_part = 1;
+               cstate->off_linkpl.constant_part = 24;  /* ipnet header length */
+               cstate->off_nl = 0;
+               cstate->off_nl_nosnap = -1;
                break;
 
        case DLT_NETANALYZER:
-               off_linkhdr.constant_part = 4;  /* Ethernet header is past 4-byte pseudo-header */
-               off_linktype.constant_part = off_linkhdr.constant_part + 12;
-               off_linkpl.constant_part = off_linkhdr.constant_part + 14;      /* pseudo-header+Ethernet header length */
-               off_nl = 0;             /* Ethernet II */
-               off_nl_nosnap = 3;      /* 802.3+802.2 */
+               cstate->off_linkhdr.constant_part = 4;  /* Ethernet header is past 4-byte pseudo-header */
+               cstate->off_linktype.constant_part = cstate->off_linkhdr.constant_part + 12;
+               cstate->off_linkpl.constant_part = cstate->off_linkhdr.constant_part + 14;      /* pseudo-header+Ethernet header length */
+               cstate->off_nl = 0;             /* Ethernet II */
+               cstate->off_nl_nosnap = 3;      /* 802.3+802.2 */
                break;
 
        case DLT_NETANALYZER_TRANSPARENT:
-               off_linkhdr.constant_part = 12; /* MAC header is past 4-byte pseudo-header, preamble, and SFD */
-               off_linktype.constant_part = off_linkhdr.constant_part + 12;
-               off_linkpl.constant_part = off_linkhdr.constant_part + 14;      /* pseudo-header+preamble+SFD+Ethernet header length */
-               off_nl = 0;             /* Ethernet II */
-               off_nl_nosnap = 3;      /* 802.3+802.2 */
+               cstate->off_linkhdr.constant_part = 12; /* MAC header is past 4-byte pseudo-header, preamble, and SFD */
+               cstate->off_linktype.constant_part = cstate->off_linkhdr.constant_part + 12;
+               cstate->off_linkpl.constant_part = cstate->off_linkhdr.constant_part + 14;      /* pseudo-header+preamble+SFD+Ethernet header length */
+               cstate->off_nl = 0;             /* Ethernet II */
+               cstate->off_nl_nosnap = 3;      /* 802.3+802.2 */
                break;
 
        default:
@@ -1565,30 +1585,31 @@ init_linktype(p)
                 * For values in the range in which we've assigned new
                 * DLT_ values, only raw "link[N:M]" filtering is supported.
                 */
-               if (linktype >= DLT_MATCHING_MIN &&
-                   linktype <= DLT_MATCHING_MAX) {
-                       off_linktype.constant_part = -1;
-                       off_linkpl.constant_part = -1;
-                       off_nl = -1;
-                       off_nl_nosnap = -1;
+               if (cstate->linktype >= DLT_MATCHING_MIN &&
+                   cstate->linktype <= DLT_MATCHING_MAX) {
+                       cstate->off_linktype.constant_part = -1;
+                       cstate->off_linkpl.constant_part = -1;
+                       cstate->off_nl = -1;
+                       cstate->off_nl_nosnap = -1;
                } else {
-                       bpf_error("unknown data link type %d", linktype);
+                       bpf_error(cstate, "unknown data link type %d", cstate->linktype);
                }
                break;
        }
 
-       off_outermostlinkhdr = off_prevlinkhdr = off_linkhdr;
+       cstate->off_outermostlinkhdr = cstate->off_prevlinkhdr = cstate->off_linkhdr;
 }
 
 /*
  * Load a value relative to the specified absolute offset.
  */
 static struct slist *
-gen_load_absoffsetrel(bpf_abs_offset *abs_offset, u_int offset, u_int size)
+gen_load_absoffsetrel(compiler_state_t *cstate, bpf_abs_offset *abs_offset,
+    u_int offset, u_int size)
 {
        struct slist *s, *s2;
 
-       s = gen_abs_offset_varpart(abs_offset);
+       s = gen_abs_offset_varpart(cstate, abs_offset);
 
        /*
         * If "s" is non-null, it has code to arrange that the X register
@@ -1605,7 +1626,7 @@ gen_load_absoffsetrel(bpf_abs_offset *abs_offset, u_int offset, u_int size)
                 * variable part of the absolute offset into the X register.
                 * Do an indirect load, to use the X register as an offset.
                 */
-               s2 = new_stmt(BPF_LD|BPF_IND|size);
+               s2 = new_stmt(cstate, BPF_LD|BPF_IND|size);
                s2->s.k = abs_offset->constant_part + offset;
                sappend(s, s2);
        } else {
@@ -1613,7 +1634,7 @@ gen_load_absoffsetrel(bpf_abs_offset *abs_offset, u_int offset, u_int size)
                 * There is no variable part of the absolute offset, so
                 * just do an absolute load.
                 */
-               s = new_stmt(BPF_LD|BPF_ABS|size);
+               s = new_stmt(cstate, BPF_LD|BPF_ABS|size);
                s->s.k = abs_offset->constant_part + offset;
        }
        return s;
@@ -1623,45 +1644,44 @@ gen_load_absoffsetrel(bpf_abs_offset *abs_offset, u_int offset, u_int size)
  * Load a value relative to the beginning of the specified header.
  */
 static struct slist *
-gen_load_a(offrel, offset, size)
-       enum e_offrel offrel;
-       u_int offset, size;
+gen_load_a(compiler_state_t *cstate, enum e_offrel offrel, u_int offset,
+    u_int size)
 {
        struct slist *s, *s2;
 
        switch (offrel) {
 
        case OR_PACKET:
-                s = new_stmt(BPF_LD|BPF_ABS|size);
+                s = new_stmt(cstate, BPF_LD|BPF_ABS|size);
                 s->s.k = offset;
                break;
 
        case OR_LINKHDR:
-               s = gen_load_absoffsetrel(&off_linkhdr, offset, size);
+               s = gen_load_absoffsetrel(cstate, &cstate->off_linkhdr, offset, size);
                break;
 
        case OR_PREVLINKHDR:
-               s = gen_load_absoffsetrel(&off_prevlinkhdr, offset, size);
+               s = gen_load_absoffsetrel(cstate, &cstate->off_prevlinkhdr, offset, size);
                break;
 
        case OR_LLC:
-               s = gen_load_absoffsetrel(&off_linkpl, offset, size);
+               s = gen_load_absoffsetrel(cstate, &cstate->off_linkpl, offset, size);
                break;
 
        case OR_PREVMPLSHDR:
-               s = gen_load_absoffsetrel(&off_linkpl, off_nl - 4 + offset, size);
+               s = gen_load_absoffsetrel(cstate, &cstate->off_linkpl, cstate->off_nl - 4 + offset, size);
                break;
 
        case OR_LINKPL:
-               s = gen_load_absoffsetrel(&off_linkpl, off_nl + offset, size);
+               s = gen_load_absoffsetrel(cstate, &cstate->off_linkpl, cstate->off_nl + offset, size);
                break;
 
        case OR_LINKPL_NOSNAP:
-               s = gen_load_absoffsetrel(&off_linkpl, off_nl_nosnap + offset, size);
+               s = gen_load_absoffsetrel(cstate, &cstate->off_linkpl, cstate->off_nl_nosnap + offset, size);
                break;
 
        case OR_LINKTYPE:
-               s = gen_load_absoffsetrel(&off_linktype, offset, size);
+               s = gen_load_absoffsetrel(cstate, &cstate->off_linktype, offset, size);
                break;
 
        case OR_TRAN_IPV4:
@@ -1671,7 +1691,7 @@ gen_load_a(offrel, offset, size)
                 * preceded by a variable-length header such as a radio
                 * header), in bytes.
                 */
-               s = gen_loadx_iphdrlen();
+               s = gen_loadx_iphdrlen(cstate);
 
                /*
                 * Load the item at {offset of the link-layer payload} +
@@ -1684,13 +1704,13 @@ gen_load_a(offrel, offset, size)
                 * value in the X register, and we include the constant
                 * part in the offset of the load.
                 */
-               s2 = new_stmt(BPF_LD|BPF_IND|size);
-               s2->s.k = off_linkpl.constant_part + off_nl + offset;
+               s2 = new_stmt(cstate, BPF_LD|BPF_IND|size);
+               s2->s.k = cstate->off_linkpl.constant_part + cstate->off_nl + offset;
                sappend(s, s2);
                break;
 
        case OR_TRAN_IPV6:
-               s = gen_load_absoffsetrel(&off_linkpl, off_nl + 40 + offset, size);
+               s = gen_load_absoffsetrel(cstate, &cstate->off_linkpl, cstate->off_nl + 40 + offset, size);
                break;
 
        default:
@@ -1706,11 +1726,11 @@ gen_load_a(offrel, offset, size)
  * payload.
  */
 static struct slist *
-gen_loadx_iphdrlen()
+gen_loadx_iphdrlen(compiler_state_t *cstate)
 {
        struct slist *s, *s2;
 
-       s = gen_abs_offset_varpart(&off_linkpl);
+       s = gen_abs_offset_varpart(cstate, &cstate->off_linkpl);
        if (s != NULL) {
                /*
                 * The offset of the link-layer payload has a variable
@@ -1722,13 +1742,13 @@ gen_loadx_iphdrlen()
                 * value in question into the A register and add to it
                 * the value from the X register.
                 */
-               s2 = new_stmt(BPF_LD|BPF_IND|BPF_B);
-               s2->s.k = off_linkpl.constant_part + off_nl;
+               s2 = new_stmt(cstate, BPF_LD|BPF_IND|BPF_B);
+               s2->s.k = cstate->off_linkpl.constant_part + cstate->off_nl;
                sappend(s, s2);
-               s2 = new_stmt(BPF_ALU|BPF_AND|BPF_K);
+               s2 = new_stmt(cstate, BPF_ALU|BPF_AND|BPF_K);
                s2->s.k = 0xf;
                sappend(s, s2);
-               s2 = new_stmt(BPF_ALU|BPF_LSH|BPF_K);
+               s2 = new_stmt(cstate, BPF_ALU|BPF_LSH|BPF_K);
                s2->s.k = 2;
                sappend(s, s2);
 
@@ -1738,8 +1758,8 @@ gen_loadx_iphdrlen()
                 * the link-layer payload, which is still in the X
                 * register, and move the result into the X register.
                 */
-               sappend(s, new_stmt(BPF_ALU|BPF_ADD|BPF_X));
-               sappend(s, new_stmt(BPF_MISC|BPF_TAX));
+               sappend(s, new_stmt(cstate, BPF_ALU|BPF_ADD|BPF_X));
+               sappend(s, new_stmt(cstate, BPF_MISC|BPF_TAX));
        } else {
                /*
                 * The offset of the link-layer payload is a constant,
@@ -1748,42 +1768,41 @@ gen_loadx_iphdrlen()
                 *
                 * This means we can use the 4*([k]&0xf) addressing
                 * mode.  Load the length of the IPv4 header, which
-                * is at an offset of off_nl from the beginning of
+                * is at an offset of cstate->off_nl from the beginning of
                 * the link-layer payload, and thus at an offset of
-                * off_linkpl.constant_part + off_nl from the beginning
+                * cstate->off_linkpl.constant_part + cstate->off_nl from the beginning
                 * of the raw packet data, using that addressing mode.
                 */
-               s = new_stmt(BPF_LDX|BPF_MSH|BPF_B);
-               s->s.k = off_linkpl.constant_part + off_nl;
+               s = new_stmt(cstate, BPF_LDX|BPF_MSH|BPF_B);
+               s->s.k = cstate->off_linkpl.constant_part + cstate->off_nl;
        }
        return s;
 }
 
 static struct block *
-gen_uncond(rsense)
-       int rsense;
+gen_uncond(compiler_state_t *cstate, int rsense)
 {
        struct block *b;
        struct slist *s;
 
-       s = new_stmt(BPF_LD|BPF_IMM);
+       s = new_stmt(cstate, BPF_LD|BPF_IMM);
        s->s.k = !rsense;
-       b = new_block(JMP(BPF_JEQ));
+       b = new_block(cstate, JMP(BPF_JEQ));
        b->stmts = s;
 
        return b;
 }
 
 static inline struct block *
-gen_true()
+gen_true(compiler_state_t *cstate)
 {
-       return gen_uncond(1);
+       return gen_uncond(cstate, 1);
 }
 
 static inline struct block *
-gen_false()
+gen_false(compiler_state_t *cstate)
 {
-       return gen_uncond(0);
+       return gen_uncond(cstate, 0);
 }
 
 /*
@@ -1804,8 +1823,7 @@ gen_false()
  * the appropriate test.
  */
 static struct block *
-gen_ether_linktype(proto)
-       register int proto;
+gen_ether_linktype(compiler_state_t *cstate, int proto)
 {
        struct block *b0, *b1;
 
@@ -1826,9 +1844,9 @@ gen_ether_linktype(proto)
                 * DSAP, as we do for other types <= ETHERMTU
                 * (i.e., other SAP values)?
                 */
-               b0 = gen_cmp_gt(OR_LINKTYPE, 0, BPF_H, ETHERMTU);
+               b0 = gen_cmp_gt(cstate, OR_LINKTYPE, 0, BPF_H, ETHERMTU);
                gen_not(b0);
-               b1 = gen_cmp(OR_LLC, 0, BPF_H, (bpf_int32)
+               b1 = gen_cmp(cstate, OR_LLC, 0, BPF_H, (bpf_int32)
                             ((proto << 8) | proto));
                gen_and(b0, b1);
                return b1;
@@ -1866,22 +1884,22 @@ gen_ether_linktype(proto)
                 * This generates code to check both for the
                 * IPX LSAP (Ethernet_802.2) and for Ethernet_802.3.
                 */
-               b0 = gen_cmp(OR_LLC, 0, BPF_B, (bpf_int32)LLCSAP_IPX);
-               b1 = gen_cmp(OR_LLC, 0, BPF_H, (bpf_int32)0xFFFF);
+               b0 = gen_cmp(cstate, OR_LLC, 0, BPF_B, (bpf_int32)LLCSAP_IPX);
+               b1 = gen_cmp(cstate, OR_LLC, 0, BPF_H, (bpf_int32)0xFFFF);
                gen_or(b0, b1);
 
                /*
                 * Now we add code to check for SNAP frames with
                 * ETHERTYPE_IPX, i.e. Ethernet_SNAP.
                 */
-               b0 = gen_snap(0x000000, ETHERTYPE_IPX);
+               b0 = gen_snap(cstate, 0x000000, ETHERTYPE_IPX);
                gen_or(b0, b1);
 
                /*
                 * Now we generate code to check for 802.3
                 * frames in general.
                 */
-               b0 = gen_cmp_gt(OR_LINKTYPE, 0, BPF_H, ETHERMTU);
+               b0 = gen_cmp_gt(cstate, OR_LINKTYPE, 0, BPF_H, ETHERMTU);
                gen_not(b0);
 
                /*
@@ -1897,7 +1915,7 @@ gen_ether_linktype(proto)
                 * do that before checking for the other frame
                 * types.
                 */
-               b0 = gen_cmp(OR_LINKTYPE, 0, BPF_H, (bpf_int32)ETHERTYPE_IPX);
+               b0 = gen_cmp(cstate, OR_LINKTYPE, 0, BPF_H, (bpf_int32)ETHERTYPE_IPX);
                gen_or(b0, b1);
                return b1;
 
@@ -1913,7 +1931,7 @@ gen_ether_linktype(proto)
                 * we check for an Ethernet type field less than
                 * 1500, which means it's an 802.3 length field.
                 */
-               b0 = gen_cmp_gt(OR_LINKTYPE, 0, BPF_H, ETHERMTU);
+               b0 = gen_cmp_gt(cstate, OR_LINKTYPE, 0, BPF_H, ETHERMTU);
                gen_not(b0);
 
                /*
@@ -1928,9 +1946,9 @@ gen_ether_linktype(proto)
                 * type of ETHERTYPE_AARP (Appletalk ARP).
                 */
                if (proto == ETHERTYPE_ATALK)
-                       b1 = gen_snap(0x080007, ETHERTYPE_ATALK);
+                       b1 = gen_snap(cstate, 0x080007, ETHERTYPE_ATALK);
                else    /* proto == ETHERTYPE_AARP */
-                       b1 = gen_snap(0x000000, ETHERTYPE_AARP);
+                       b1 = gen_snap(cstate, 0x000000, ETHERTYPE_AARP);
                gen_and(b0, b1);
 
                /*
@@ -1938,7 +1956,7 @@ gen_ether_linktype(proto)
                 * phase 1?); we just check for the Ethernet
                 * protocol type.
                 */
-               b0 = gen_cmp(OR_LINKTYPE, 0, BPF_H, (bpf_int32)proto);
+               b0 = gen_cmp(cstate, OR_LINKTYPE, 0, BPF_H, (bpf_int32)proto);
 
                gen_or(b0, b1);
                return b1;
@@ -1953,9 +1971,9 @@ gen_ether_linktype(proto)
                         * a length field, <= ETHERMTU) and
                         * then check the DSAP.
                         */
-                       b0 = gen_cmp_gt(OR_LINKTYPE, 0, BPF_H, ETHERMTU);
+                       b0 = gen_cmp_gt(cstate, OR_LINKTYPE, 0, BPF_H, ETHERMTU);
                        gen_not(b0);
-                       b1 = gen_cmp(OR_LINKTYPE, 2, BPF_B, (bpf_int32)proto);
+                       b1 = gen_cmp(cstate, OR_LINKTYPE, 2, BPF_B, (bpf_int32)proto);
                        gen_and(b0, b1);
                        return b1;
                } else {
@@ -1968,7 +1986,7 @@ gen_ether_linktype(proto)
                         * will fail and the frame won't match,
                         * which is what we want).
                         */
-                       return gen_cmp(OR_LINKTYPE, 0, BPF_H,
+                       return gen_cmp(cstate, OR_LINKTYPE, 0, BPF_H,
                            (bpf_int32)proto);
                }
        }
@@ -1979,17 +1997,16 @@ gen_ether_linktype(proto)
  * or IPv6 then we have an error.
  */
 static struct block *
-gen_ipnet_linktype(proto)
-       register int proto;
+gen_ipnet_linktype(compiler_state_t *cstate, int proto)
 {
        switch (proto) {
 
        case ETHERTYPE_IP:
-               return gen_cmp(OR_LINKTYPE, 0, BPF_B, (bpf_int32)IPH_AF_INET);
+               return gen_cmp(cstate, OR_LINKTYPE, 0, BPF_B, (bpf_int32)IPH_AF_INET);
                /* NOTREACHED */
 
        case ETHERTYPE_IPV6:
-               return gen_cmp(OR_LINKTYPE, 0, BPF_B,
+               return gen_cmp(cstate, OR_LINKTYPE, 0, BPF_B,
                    (bpf_int32)IPH_AF_INET6);
                /* NOTREACHED */
 
@@ -1997,7 +2014,7 @@ gen_ipnet_linktype(proto)
                break;
        }
 
-       return gen_false();
+       return gen_false(cstate);
 }
 
 /*
@@ -2009,8 +2026,7 @@ gen_ipnet_linktype(proto)
  * LINUX_SLL_P_802_2 value and then do the appropriate test.
  */
 static struct block *
-gen_linux_sll_linktype(proto)
-       register int proto;
+gen_linux_sll_linktype(compiler_state_t *cstate, int proto)
 {
        struct block *b0, *b1;
 
@@ -2031,8 +2047,8 @@ gen_linux_sll_linktype(proto)
                 * DSAP, as we do for other types <= ETHERMTU
                 * (i.e., other SAP values)?
                 */
-               b0 = gen_cmp(OR_LINKTYPE, 0, BPF_H, LINUX_SLL_P_802_2);
-               b1 = gen_cmp(OR_LLC, 0, BPF_H, (bpf_int32)
+               b0 = gen_cmp(cstate, OR_LINKTYPE, 0, BPF_H, LINUX_SLL_P_802_2);
+               b1 = gen_cmp(cstate, OR_LLC, 0, BPF_H, (bpf_int32)
                             ((proto << 8) | proto));
                gen_and(b0, b1);
                return b1;
@@ -2063,17 +2079,17 @@ gen_linux_sll_linktype(proto)
                 * then put a check for LINUX_SLL_P_802_2 frames
                 * before it.
                 */
-               b0 = gen_cmp(OR_LLC, 0, BPF_B, (bpf_int32)LLCSAP_IPX);
-               b1 = gen_snap(0x000000, ETHERTYPE_IPX);
+               b0 = gen_cmp(cstate, OR_LLC, 0, BPF_B, (bpf_int32)LLCSAP_IPX);
+               b1 = gen_snap(cstate, 0x000000, ETHERTYPE_IPX);
                gen_or(b0, b1);
-               b0 = gen_cmp(OR_LINKTYPE, 0, BPF_H, LINUX_SLL_P_802_2);
+               b0 = gen_cmp(cstate, OR_LINKTYPE, 0, BPF_H, LINUX_SLL_P_802_2);
                gen_and(b0, b1);
 
                /*
                 * Now check for 802.3 frames and OR that with
                 * the previous test.
                 */
-               b0 = gen_cmp(OR_LINKTYPE, 0, BPF_H, LINUX_SLL_P_802_3);
+               b0 = gen_cmp(cstate, OR_LINKTYPE, 0, BPF_H, LINUX_SLL_P_802_3);
                gen_or(b0, b1);
 
                /*
@@ -2081,7 +2097,7 @@ gen_linux_sll_linktype(proto)
                 * do that before checking for the other frame
                 * types.
                 */
-               b0 = gen_cmp(OR_LINKTYPE, 0, BPF_H, (bpf_int32)ETHERTYPE_IPX);
+               b0 = gen_cmp(cstate, OR_LINKTYPE, 0, BPF_H, (bpf_int32)ETHERTYPE_IPX);
                gen_or(b0, b1);
                return b1;
 
@@ -2097,7 +2113,7 @@ gen_linux_sll_linktype(proto)
                 * we check for the 802.2 protocol type in the
                 * "Ethernet type" field.
                 */
-               b0 = gen_cmp(OR_LINKTYPE, 0, BPF_H, LINUX_SLL_P_802_2);
+               b0 = gen_cmp(cstate, OR_LINKTYPE, 0, BPF_H, LINUX_SLL_P_802_2);
 
                /*
                 * 802.2-encapsulated ETHERTYPE_ATALK packets are
@@ -2111,9 +2127,9 @@ gen_linux_sll_linktype(proto)
                 * type of ETHERTYPE_AARP (Appletalk ARP).
                 */
                if (proto == ETHERTYPE_ATALK)
-                       b1 = gen_snap(0x080007, ETHERTYPE_ATALK);
+                       b1 = gen_snap(cstate, 0x080007, ETHERTYPE_ATALK);
                else    /* proto == ETHERTYPE_AARP */
-                       b1 = gen_snap(0x000000, ETHERTYPE_AARP);
+                       b1 = gen_snap(cstate, 0x000000, ETHERTYPE_AARP);
                gen_and(b0, b1);
 
                /*
@@ -2121,7 +2137,7 @@ gen_linux_sll_linktype(proto)
                 * phase 1?); we just check for the Ethernet
                 * protocol type.
                 */
-               b0 = gen_cmp(OR_LINKTYPE, 0, BPF_H, (bpf_int32)proto);
+               b0 = gen_cmp(cstate, OR_LINKTYPE, 0, BPF_H, (bpf_int32)proto);
 
                gen_or(b0, b1);
                return b1;
@@ -2135,8 +2151,8 @@ gen_linux_sll_linktype(proto)
                         * in the "Ethernet type" field, and
                         * then check the DSAP.
                         */
-                       b0 = gen_cmp(OR_LINKTYPE, 0, BPF_H, LINUX_SLL_P_802_2);
-                       b1 = gen_cmp(OR_LINKHDR, off_linkpl.constant_part, BPF_B,
+                       b0 = gen_cmp(cstate, OR_LINKTYPE, 0, BPF_H, LINUX_SLL_P_802_2);
+                       b1 = gen_cmp(cstate, OR_LINKHDR, cstate->off_linkpl.constant_part, BPF_B,
                             (bpf_int32)proto);
                        gen_and(b0, b1);
                        return b1;
@@ -2150,13 +2166,13 @@ gen_linux_sll_linktype(proto)
                         * will fail and the frame won't match,
                         * which is what we want).
                         */
-                       return gen_cmp(OR_LINKTYPE, 0, BPF_H, (bpf_int32)proto);
+                       return gen_cmp(cstate, OR_LINKTYPE, 0, BPF_H, (bpf_int32)proto);
                }
        }
 }
 
 static struct slist *
-gen_load_prism_llprefixlen()
+gen_load_prism_llprefixlen(compiler_state_t *cstate)
 {
        struct slist *s1, *s2;
        struct slist *sjeq_avs_cookie;
@@ -2167,7 +2183,7 @@ gen_load_prism_llprefixlen()
         * we are generating jmp instructions within a normal
         * slist of instructions
         */
-       no_optimize = 1;
+       cstate->no_optimize = 1;
 
        /*
         * Generate code to load the length of the radio header into
@@ -2188,24 +2204,24 @@ gen_load_prism_llprefixlen()
         * but no known software generates headers that aren't 144
         * bytes long.
         */
-       if (off_linkhdr.reg != -1) {
+       if (cstate->off_linkhdr.reg != -1) {
                /*
                 * Load the cookie.
                 */
-               s1 = new_stmt(BPF_LD|BPF_W|BPF_ABS);
+               s1 = new_stmt(cstate, BPF_LD|BPF_W|BPF_ABS);
                s1->s.k = 0;
 
                /*
                 * AND it with 0xFFFFF000.
                 */
-               s2 = new_stmt(BPF_ALU|BPF_AND|BPF_K);
+               s2 = new_stmt(cstate, BPF_ALU|BPF_AND|BPF_K);
                s2->s.k = 0xFFFFF000;
                sappend(s1, s2);
 
                /*
                 * Compare with 0x80211000.
                 */
-               sjeq_avs_cookie = new_stmt(JMP(BPF_JEQ));
+               sjeq_avs_cookie = new_stmt(cstate, JMP(BPF_JEQ));
                sjeq_avs_cookie->s.k = 0x80211000;
                sappend(s1, sjeq_avs_cookie);
 
@@ -2216,7 +2232,7 @@ gen_load_prism_llprefixlen()
                 * the AVS header are the length of the AVS header.
                 * That field is big-endian.
                 */
-               s2 = new_stmt(BPF_LD|BPF_W|BPF_ABS);
+               s2 = new_stmt(cstate, BPF_LD|BPF_W|BPF_ABS);
                s2->s.k = 4;
                sappend(s1, s2);
                sjeq_avs_cookie->s.jt = s2;
@@ -2229,7 +2245,7 @@ gen_load_prism_llprefixlen()
                 * it's added to the PC, so, as we're jumping
                 * over a single instruction, it should be 1.)
                 */
-               sjcommon = new_stmt(JMP(BPF_JA));
+               sjcommon = new_stmt(cstate, JMP(BPF_JA));
                sjcommon->s.k = 1;
                sappend(s1, sjcommon);
 
@@ -2239,7 +2255,7 @@ gen_load_prism_llprefixlen()
                 * into the A register.  Have the test for an AVS
                 * header branch here if we don't have an AVS header.
                 */
-               s2 = new_stmt(BPF_LD|BPF_W|BPF_IMM);
+               s2 = new_stmt(cstate, BPF_LD|BPF_W|BPF_IMM);
                s2->s.k = 144;
                sappend(s1, s2);
                sjeq_avs_cookie->s.jf = s2;
@@ -2249,15 +2265,15 @@ gen_load_prism_llprefixlen()
                 * it.  The code for the AVS header will jump here after
                 * loading the length of the AVS header.
                 */
-               s2 = new_stmt(BPF_ST);
-               s2->s.k = off_linkhdr.reg;
+               s2 = new_stmt(cstate, BPF_ST);
+               s2->s.k = cstate->off_linkhdr.reg;
                sappend(s1, s2);
                sjcommon->s.jf = s2;
 
                /*
                 * Now move it into the X register.
                 */
-               s2 = new_stmt(BPF_MISC|BPF_TAX);
+               s2 = new_stmt(cstate, BPF_MISC|BPF_TAX);
                sappend(s1, s2);
 
                return (s1);
@@ -2266,7 +2282,7 @@ gen_load_prism_llprefixlen()
 }
 
 static struct slist *
-gen_load_avs_llprefixlen()
+gen_load_avs_llprefixlen(compiler_state_t *cstate)
 {
        struct slist *s1, *s2;
 
@@ -2277,27 +2293,27 @@ gen_load_avs_llprefixlen()
         * generated uses that prefix, so we don't need to generate any
         * code to load it.)
         */
-       if (off_linkhdr.reg != -1) {
+       if (cstate->off_linkhdr.reg != -1) {
                /*
                 * The 4 bytes at an offset of 4 from the beginning of
                 * the AVS header are the length of the AVS header.
                 * That field is big-endian.
                 */
-               s1 = new_stmt(BPF_LD|BPF_W|BPF_ABS);
+               s1 = new_stmt(cstate, BPF_LD|BPF_W|BPF_ABS);
                s1->s.k = 4;
 
                /*
                 * Now allocate a register to hold that value and store
                 * it.
                 */
-               s2 = new_stmt(BPF_ST);
-               s2->s.k = off_linkhdr.reg;
+               s2 = new_stmt(cstate, BPF_ST);
+               s2->s.k = cstate->off_linkhdr.reg;
                sappend(s1, s2);
 
                /*
                 * Now move it into the X register.
                 */
-               s2 = new_stmt(BPF_MISC|BPF_TAX);
+               s2 = new_stmt(cstate, BPF_MISC|BPF_TAX);
                sappend(s1, s2);
 
                return (s1);
@@ -2306,7 +2322,7 @@ gen_load_avs_llprefixlen()
 }
 
 static struct slist *
-gen_load_radiotap_llprefixlen()
+gen_load_radiotap_llprefixlen(compiler_state_t *cstate)
 {
        struct slist *s1, *s2;
 
@@ -2317,7 +2333,7 @@ gen_load_radiotap_llprefixlen()
         * generated uses that prefix, so we don't need to generate any
         * code to load it.)
         */
-       if (off_linkhdr.reg != -1) {
+       if (cstate->off_linkhdr.reg != -1) {
                /*
                 * The 2 bytes at offsets of 2 and 3 from the beginning
                 * of the radiotap header are the length of the radiotap
@@ -2329,36 +2345,36 @@ gen_load_radiotap_llprefixlen()
                 * Load the high-order byte, at an offset of 3, shift it
                 * left a byte, and put the result in the X register.
                 */
-               s1 = new_stmt(BPF_LD|BPF_B|BPF_ABS);
+               s1 = new_stmt(cstate, BPF_LD|BPF_B|BPF_ABS);
                s1->s.k = 3;
-               s2 = new_stmt(BPF_ALU|BPF_LSH|BPF_K);
+               s2 = new_stmt(cstate, BPF_ALU|BPF_LSH|BPF_K);
                sappend(s1, s2);
                s2->s.k = 8;
-               s2 = new_stmt(BPF_MISC|BPF_TAX);
+               s2 = new_stmt(cstate, BPF_MISC|BPF_TAX);
                sappend(s1, s2);
 
                /*
                 * Load the next byte, at an offset of 2, and OR the
                 * value from the X register into it.
                 */
-               s2 = new_stmt(BPF_LD|BPF_B|BPF_ABS);
+               s2 = new_stmt(cstate, BPF_LD|BPF_B|BPF_ABS);
                sappend(s1, s2);
                s2->s.k = 2;
-               s2 = new_stmt(BPF_ALU|BPF_OR|BPF_X);
+               s2 = new_stmt(cstate, BPF_ALU|BPF_OR|BPF_X);
                sappend(s1, s2);
 
                /*
                 * Now allocate a register to hold that value and store
                 * it.
                 */
-               s2 = new_stmt(BPF_ST);
-               s2->s.k = off_linkhdr.reg;
+               s2 = new_stmt(cstate, BPF_ST);
+               s2->s.k = cstate->off_linkhdr.reg;
                sappend(s1, s2);
 
                /*
                 * Now move it into the X register.
                 */
-               s2 = new_stmt(BPF_MISC|BPF_TAX);
+               s2 = new_stmt(cstate, BPF_MISC|BPF_TAX);
                sappend(s1, s2);
 
                return (s1);
@@ -2376,7 +2392,7 @@ gen_load_radiotap_llprefixlen()
  * that's done in finish_parse().
  */
 static struct slist *
-gen_load_ppi_llprefixlen()
+gen_load_ppi_llprefixlen(compiler_state_t *cstate)
 {
        struct slist *s1, *s2;
 
@@ -2385,7 +2401,7 @@ gen_load_ppi_llprefixlen()
         * into the register assigned to hold that length, if one has
         * been assigned.
         */
-       if (off_linkhdr.reg != -1) {
+       if (cstate->off_linkhdr.reg != -1) {
                /*
                 * The 2 bytes at offsets of 2 and 3 from the beginning
                 * of the radiotap header are the length of the radiotap
@@ -2397,36 +2413,36 @@ gen_load_ppi_llprefixlen()
                 * Load the high-order byte, at an offset of 3, shift it
                 * left a byte, and put the result in the X register.
                 */
-               s1 = new_stmt(BPF_LD|BPF_B|BPF_ABS);
+               s1 = new_stmt(cstate, BPF_LD|BPF_B|BPF_ABS);
                s1->s.k = 3;
-               s2 = new_stmt(BPF_ALU|BPF_LSH|BPF_K);
+               s2 = new_stmt(cstate, BPF_ALU|BPF_LSH|BPF_K);
                sappend(s1, s2);
                s2->s.k = 8;
-               s2 = new_stmt(BPF_MISC|BPF_TAX);
+               s2 = new_stmt(cstate, BPF_MISC|BPF_TAX);
                sappend(s1, s2);
 
                /*
                 * Load the next byte, at an offset of 2, and OR the
                 * value from the X register into it.
                 */
-               s2 = new_stmt(BPF_LD|BPF_B|BPF_ABS);
+               s2 = new_stmt(cstate, BPF_LD|BPF_B|BPF_ABS);
                sappend(s1, s2);
                s2->s.k = 2;
-               s2 = new_stmt(BPF_ALU|BPF_OR|BPF_X);
+               s2 = new_stmt(cstate, BPF_ALU|BPF_OR|BPF_X);
                sappend(s1, s2);
 
                /*
                 * Now allocate a register to hold that value and store
                 * it.
                 */
-               s2 = new_stmt(BPF_ST);
-               s2->s.k = off_linkhdr.reg;
+               s2 = new_stmt(cstate, BPF_ST);
+               s2->s.k = cstate->off_linkhdr.reg;
                sappend(s1, s2);
 
                /*
                 * Now move it into the X register.
                 */
-               s2 = new_stmt(BPF_MISC|BPF_TAX);
+               s2 = new_stmt(cstate, BPF_MISC|BPF_TAX);
                sappend(s1, s2);
 
                return (s1);
@@ -2442,7 +2458,7 @@ gen_load_ppi_llprefixlen()
  * radio information.
  */
 static struct slist *
-gen_load_802_11_header_len(struct slist *s, struct slist *snext)
+gen_load_802_11_header_len(compiler_state_t *cstate, struct slist *s, struct slist *snext)
 {
        struct slist *s2;
        struct slist *sjset_data_frame_1;
@@ -2454,7 +2470,7 @@ gen_load_802_11_header_len(struct slist *s, struct slist *snext)
        struct slist *sjset_tsft_datapad, *sjset_notsft_datapad;
        struct slist *s_roundup;
 
-       if (off_linkpl.reg == -1) {
+       if (cstate->off_linkpl.reg == -1) {
                /*
                 * No register has been assigned to the offset of
                 * the link-layer payload, which means nobody needs
@@ -2469,7 +2485,7 @@ gen_load_802_11_header_len(struct slist *s, struct slist *snext)
         * we are generating jmp instructions within a normal
         * slist of instructions
         */
-       no_optimize = 1;
+       cstate->no_optimize = 1;
 
        /*
         * If "s" is non-null, it has code to arrange that the X register
@@ -2486,30 +2502,30 @@ gen_load_802_11_header_len(struct slist *s, struct slist *snext)
                 *
                 * Load the length of the fixed-length prefix preceding
                 * the link-layer header (if any) into the X register,
-                * and store it in the off_linkpl.reg register.
+                * and store it in the cstate->off_linkpl.reg register.
                 * That length is off_outermostlinkhdr.constant_part.
                 */
-               s = new_stmt(BPF_LDX|BPF_IMM);
-               s->s.k = off_outermostlinkhdr.constant_part;
+               s = new_stmt(cstate, BPF_LDX|BPF_IMM);
+               s->s.k = cstate->off_outermostlinkhdr.constant_part;
        }
 
        /*
         * The X register contains the offset of the beginning of the
         * link-layer header; add 24, which is the minimum length
         * of the MAC header for a data frame, to that, and store it
-        * in off_linkpl.reg, and then load the Frame Control field,
+        * in cstate->off_linkpl.reg, and then load the Frame Control field,
         * which is at the offset in the X register, with an indexed load.
         */
-       s2 = new_stmt(BPF_MISC|BPF_TXA);
+       s2 = new_stmt(cstate, BPF_MISC|BPF_TXA);
        sappend(s, s2);
-       s2 = new_stmt(BPF_ALU|BPF_ADD|BPF_K);
+       s2 = new_stmt(cstate, BPF_ALU|BPF_ADD|BPF_K);
        s2->s.k = 24;
        sappend(s, s2);
-       s2 = new_stmt(BPF_ST);
-       s2->s.k = off_linkpl.reg;
+       s2 = new_stmt(cstate, BPF_ST);
+       s2->s.k = cstate->off_linkpl.reg;
        sappend(s, s2);
 
-       s2 = new_stmt(BPF_LD|BPF_IND|BPF_B);
+       s2 = new_stmt(cstate, BPF_LD|BPF_IND|BPF_B);
        s2->s.k = 0;
        sappend(s, s2);
 
@@ -2518,7 +2534,7 @@ gen_load_802_11_header_len(struct slist *s, struct slist *snext)
         * a data frame has the 0x08 bit (b3) in that field set and the
         * 0x04 bit (b2) clear.
         */
-       sjset_data_frame_1 = new_stmt(JMP(BPF_JSET));
+       sjset_data_frame_1 = new_stmt(cstate, JMP(BPF_JSET));
        sjset_data_frame_1->s.k = 0x08;
        sappend(s, sjset_data_frame_1);
 
@@ -2526,7 +2542,7 @@ gen_load_802_11_header_len(struct slist *s, struct slist *snext)
         * If b3 is set, test b2, otherwise go to the first statement of
         * the rest of the program.
         */
-       sjset_data_frame_1->s.jt = sjset_data_frame_2 = new_stmt(JMP(BPF_JSET));
+       sjset_data_frame_1->s.jt = sjset_data_frame_2 = new_stmt(cstate, JMP(BPF_JSET));
        sjset_data_frame_2->s.k = 0x04;
        sappend(s, sjset_data_frame_2);
        sjset_data_frame_1->s.jf = snext;
@@ -2537,24 +2553,24 @@ gen_load_802_11_header_len(struct slist *s, struct slist *snext)
         * program.
         */
        sjset_data_frame_2->s.jt = snext;
-       sjset_data_frame_2->s.jf = sjset_qos = new_stmt(JMP(BPF_JSET));
+       sjset_data_frame_2->s.jf = sjset_qos = new_stmt(cstate, JMP(BPF_JSET));
        sjset_qos->s.k = 0x80;  /* QoS bit */
        sappend(s, sjset_qos);
 
        /*
-        * If it's set, add 2 to off_linkpl.reg, to skip the QoS
+        * If it's set, add 2 to cstate->off_linkpl.reg, to skip the QoS
         * field.
         * Otherwise, go to the first statement of the rest of the
         * program.
         */
-       sjset_qos->s.jt = s2 = new_stmt(BPF_LD|BPF_MEM);
-       s2->s.k = off_linkpl.reg;
+       sjset_qos->s.jt = s2 = new_stmt(cstate, BPF_LD|BPF_MEM);
+       s2->s.k = cstate->off_linkpl.reg;
        sappend(s, s2);
-       s2 = new_stmt(BPF_ALU|BPF_ADD|BPF_IMM);
+       s2 = new_stmt(cstate, BPF_ALU|BPF_ADD|BPF_IMM);
        s2->s.k = 2;
        sappend(s, s2);
-       s2 = new_stmt(BPF_ST);
-       s2->s.k = off_linkpl.reg;
+       s2 = new_stmt(cstate, BPF_ST);
+       s2->s.k = cstate->off_linkpl.reg;
        sappend(s, s2);
 
        /*
@@ -2576,16 +2592,16 @@ gen_load_802_11_header_len(struct slist *s, struct slist *snext)
         * annoying padding don't have multiple antennae and therefore
         * do not generate radiotap headers with multiple presence words.
         */
-       if (linktype == DLT_IEEE802_11_RADIO) {
+       if (cstate->linktype == DLT_IEEE802_11_RADIO) {
                /*
                 * Is the IEEE80211_RADIOTAP_FLAGS bit (0x0000002) set
                 * in the first presence flag word?
                 */
-               sjset_qos->s.jf = s2 = new_stmt(BPF_LD|BPF_ABS|BPF_W);
+               sjset_qos->s.jf = s2 = new_stmt(cstate, BPF_LD|BPF_ABS|BPF_W);
                s2->s.k = 4;
                sappend(s, s2);
 
-               sjset_radiotap_flags_present = new_stmt(JMP(BPF_JSET));
+               sjset_radiotap_flags_present = new_stmt(cstate, JMP(BPF_JSET));
                sjset_radiotap_flags_present->s.k = SWAPLONG(0x00000002);
                sappend(s, sjset_radiotap_flags_present);
 
@@ -2597,7 +2613,7 @@ gen_load_802_11_header_len(struct slist *s, struct slist *snext)
                /*
                 * Otherwise, is the "extension" bit set in that word?
                 */
-               sjset_radiotap_ext_present = new_stmt(JMP(BPF_JSET));
+               sjset_radiotap_ext_present = new_stmt(cstate, JMP(BPF_JSET));
                sjset_radiotap_ext_present->s.k = SWAPLONG(0x80000000);
                sappend(s, sjset_radiotap_ext_present);
                sjset_radiotap_flags_present->s.jt = sjset_radiotap_ext_present;
@@ -2610,7 +2626,7 @@ gen_load_802_11_header_len(struct slist *s, struct slist *snext)
                /*
                 * Otherwise, is the IEEE80211_RADIOTAP_TSFT bit set?
                 */
-               sjset_radiotap_tsft_present = new_stmt(JMP(BPF_JSET));
+               sjset_radiotap_tsft_present = new_stmt(cstate, JMP(BPF_JSET));
                sjset_radiotap_tsft_present->s.k = SWAPLONG(0x00000001);
                sappend(s, sjset_radiotap_tsft_present);
                sjset_radiotap_ext_present->s.jf = sjset_radiotap_tsft_present;
@@ -2624,12 +2640,12 @@ gen_load_802_11_header_len(struct slist *s, struct slist *snext)
                 * Test whether the IEEE80211_RADIOTAP_F_DATAPAD bit (0x20)
                 * is set.
                 */
-               s2 = new_stmt(BPF_LD|BPF_ABS|BPF_B);
+               s2 = new_stmt(cstate, BPF_LD|BPF_ABS|BPF_B);
                s2->s.k = 16;
                sappend(s, s2);
                sjset_radiotap_tsft_present->s.jt = s2;
 
-               sjset_tsft_datapad = new_stmt(JMP(BPF_JSET));
+               sjset_tsft_datapad = new_stmt(cstate, JMP(BPF_JSET));
                sjset_tsft_datapad->s.k = 0x20;
                sappend(s, sjset_tsft_datapad);
 
@@ -2641,12 +2657,12 @@ gen_load_802_11_header_len(struct slist *s, struct slist *snext)
                 * Test whether the IEEE80211_RADIOTAP_F_DATAPAD bit (0x20)
                 * is set.
                 */
-               s2 = new_stmt(BPF_LD|BPF_ABS|BPF_B);
+               s2 = new_stmt(cstate, BPF_LD|BPF_ABS|BPF_B);
                s2->s.k = 8;
                sappend(s, s2);
                sjset_radiotap_tsft_present->s.jf = s2;
 
-               sjset_notsft_datapad = new_stmt(JMP(BPF_JSET));
+               sjset_notsft_datapad = new_stmt(cstate, JMP(BPF_JSET));
                sjset_notsft_datapad->s.k = 0x20;
                sappend(s, sjset_notsft_datapad);
 
@@ -2657,17 +2673,17 @@ gen_load_802_11_header_len(struct slist *s, struct slist *snext)
                 * dividing by and multiplying by 4, which we do by
                 * ANDing with ~3.
                 */
-               s_roundup = new_stmt(BPF_LD|BPF_MEM);
-               s_roundup->s.k = off_linkpl.reg;
+               s_roundup = new_stmt(cstate, BPF_LD|BPF_MEM);
+               s_roundup->s.k = cstate->off_linkpl.reg;
                sappend(s, s_roundup);
-               s2 = new_stmt(BPF_ALU|BPF_ADD|BPF_IMM);
+               s2 = new_stmt(cstate, BPF_ALU|BPF_ADD|BPF_IMM);
                s2->s.k = 3;
                sappend(s, s2);
-               s2 = new_stmt(BPF_ALU|BPF_AND|BPF_IMM);
+               s2 = new_stmt(cstate, BPF_ALU|BPF_AND|BPF_IMM);
                s2->s.k = ~3;
                sappend(s, s2);
-               s2 = new_stmt(BPF_ST);
-               s2->s.k = off_linkpl.reg;
+               s2 = new_stmt(cstate, BPF_ST);
+               s2->s.k = cstate->off_linkpl.reg;
                sappend(s, s2);
 
                sjset_tsft_datapad->s.jt = s_roundup;
@@ -2681,8 +2697,7 @@ gen_load_802_11_header_len(struct slist *s, struct slist *snext)
 }
 
 static void
-insert_compute_vloffsets(b)
-       struct block *b;
+insert_compute_vloffsets(compiler_state_t *cstate, struct block *b)
 {
        struct slist *s;
 
@@ -2691,9 +2706,9 @@ insert_compute_vloffsets(b)
         * includes the variable part of the header. Therefore,
         * if nobody else has allocated a register for the link
         * header and we need it, do it now. */
-       if (off_linkpl.reg != -1 && off_linkhdr.is_variable &&
-           off_linkhdr.reg == -1)
-               off_linkhdr.reg = alloc_reg();
+       if (cstate->off_linkpl.reg != -1 && cstate->off_linkhdr.is_variable &&
+           cstate->off_linkhdr.reg == -1)
+               cstate->off_linkhdr.reg = alloc_reg(cstate);
 
        /*
         * For link-layer types that have a variable-length header
@@ -2706,22 +2721,22 @@ insert_compute_vloffsets(b)
         * some other protocol stack.  That's significantly more
         * complicated.
         */
-       switch (outermostlinktype) {
+       switch (cstate->outermostlinktype) {
 
        case DLT_PRISM_HEADER:
-               s = gen_load_prism_llprefixlen();
+               s = gen_load_prism_llprefixlen(cstate);
                break;
 
        case DLT_IEEE802_11_RADIO_AVS:
-               s = gen_load_avs_llprefixlen();
+               s = gen_load_avs_llprefixlen(cstate);
                break;
 
        case DLT_IEEE802_11_RADIO:
-               s = gen_load_radiotap_llprefixlen();
+               s = gen_load_radiotap_llprefixlen(cstate);
                break;
 
        case DLT_PPI:
-               s = gen_load_ppi_llprefixlen();
+               s = gen_load_ppi_llprefixlen(cstate);
                break;
 
        default:
@@ -2734,14 +2749,14 @@ insert_compute_vloffsets(b)
         * header, generate code to load the offset of the link-layer
         * payload into the register assigned to that offset, if any.
         */
-       switch (outermostlinktype) {
+       switch (cstate->outermostlinktype) {
 
        case DLT_IEEE802_11:
        case DLT_PRISM_HEADER:
        case DLT_IEEE802_11_RADIO_AVS:
        case DLT_IEEE802_11_RADIO:
        case DLT_PPI:
-               s = gen_load_802_11_header_len(s, b->stmts);
+               s = gen_load_802_11_header_len(cstate, s, b->stmts);
                break;
        }
 
@@ -2758,19 +2773,19 @@ insert_compute_vloffsets(b)
 }
 
 static struct block *
-gen_ppi_dlt_check(void)
+gen_ppi_dlt_check(compiler_state_t *cstate)
 {
        struct slist *s_load_dlt;
        struct block *b;
 
-       if (linktype == DLT_PPI)
+       if (cstate->linktype == DLT_PPI)
        {
                /* Create the statements that check for the DLT
                 */
-               s_load_dlt = new_stmt(BPF_LD|BPF_W|BPF_ABS);
+               s_load_dlt = new_stmt(cstate, BPF_LD|BPF_W|BPF_ABS);
                s_load_dlt->s.k = 4;
 
-               b = new_block(JMP(BPF_JEQ));
+               b = new_block(cstate, JMP(BPF_JEQ));
 
                b->stmts = s_load_dlt;
                b->s.k = SWAPLONG(DLT_IEEE802_11);
@@ -2797,7 +2812,7 @@ gen_ppi_dlt_check(void)
  * be placed earlier in the code sequence.)
  */
 static struct slist *
-gen_abs_offset_varpart(bpf_abs_offset *off)
+gen_abs_offset_varpart(compiler_state_t *cstate, bpf_abs_offset *off)
 {
        struct slist *s;
 
@@ -2808,14 +2823,14 @@ gen_abs_offset_varpart(bpf_abs_offset *off)
                         * variable part of the offset of the link-layer
                         * header; allocate one.
                         */
-                       off->reg = alloc_reg();
+                       off->reg = alloc_reg(cstate);
                }
 
                /*
                 * Load the register containing the variable part of the
                 * offset of the link-layer header into the X register.
                 */
-               s = new_stmt(BPF_LDX|BPF_MEM);
+               s = new_stmt(cstate, BPF_LDX|BPF_MEM);
                s->s.k = off->reg;
                return s;
        } else {
@@ -2883,14 +2898,14 @@ ethertype_to_ppptype(proto)
  * for that encapsulation).
  */
 static struct block *
-gen_prevlinkhdr_check(void)
+gen_prevlinkhdr_check(compiler_state_t *cstate)
 {
        struct block *b0;
 
-       if (is_geneve)
-               return gen_geneve_ll_check();
+       if (cstate->is_geneve)
+               return gen_geneve_ll_check(cstate);
 
-       switch (prevlinktype) {
+       switch (cstate->prevlinktype) {
 
        case DLT_SUNATM:
                /*
@@ -2900,7 +2915,7 @@ gen_prevlinkhdr_check(void)
                 *
                 * (We've already generated a test for LANE.)
                 */
-               b0 = gen_cmp(OR_PREVLINKHDR, SUNATM_PKT_BEGIN_POS, BPF_H, 0xFF00);
+               b0 = gen_cmp(cstate, OR_PREVLINKHDR, SUNATM_PKT_BEGIN_POS, BPF_H, 0xFF00);
                gen_not(b0);
                return b0;
 
@@ -2921,44 +2936,43 @@ gen_prevlinkhdr_check(void)
  * value, if <= ETHERMTU.
  */
 static struct block *
-gen_linktype(proto)
-       register int proto;
+gen_linktype(compiler_state_t *cstate, int proto)
 {
        struct block *b0, *b1, *b2;
        const char *description;
 
        /* are we checking MPLS-encapsulated packets? */
-       if (label_stack_depth > 0) {
+       if (cstate->label_stack_depth > 0) {
                switch (proto) {
                case ETHERTYPE_IP:
                case PPP_IP:
                        /* FIXME add other L3 proto IDs */
-                       return gen_mpls_linktype(Q_IP);
+                       return gen_mpls_linktype(cstate, Q_IP);
 
                case ETHERTYPE_IPV6:
                case PPP_IPV6:
                        /* FIXME add other L3 proto IDs */
-                       return gen_mpls_linktype(Q_IPV6);
+                       return gen_mpls_linktype(cstate, Q_IPV6);
 
                default:
-                       bpf_error("unsupported protocol over mpls");
+                       bpf_error(cstate, "unsupported protocol over mpls");
                        /* NOTREACHED */
                }
        }
 
-       switch (linktype) {
+       switch (cstate->linktype) {
 
        case DLT_EN10MB:
        case DLT_NETANALYZER:
        case DLT_NETANALYZER_TRANSPARENT:
                /* Geneve has an EtherType regardless of whether there is an
                 * L2 header. */
-               if (!is_geneve)
-                       b0 = gen_prevlinkhdr_check();
+               if (!cstate->is_geneve)
+                       b0 = gen_prevlinkhdr_check(cstate);
                else
                        b0 = NULL;
 
-               b1 = gen_ether_linktype(proto);
+               b1 = gen_ether_linktype(cstate, proto);
                if (b0 != NULL)
                        gen_and(b0, b1);
                return b1;
@@ -2973,7 +2987,7 @@ gen_linktype(proto)
                        /* fall through */
 
                default:
-                       return gen_cmp(OR_LINKTYPE, 0, BPF_H, (bpf_int32)proto);
+                       return gen_cmp(cstate, OR_LINKTYPE, 0, BPF_H, (bpf_int32)proto);
                        /*NOTREACHED*/
                        break;
                }
@@ -2987,12 +3001,12 @@ gen_linktype(proto)
                /*
                 * Check that we have a data frame.
                 */
-               b0 = gen_check_802_11_data_frame();
+               b0 = gen_check_802_11_data_frame(cstate);
 
                /*
                 * Now check for the specified link-layer type.
                 */
-               b1 = gen_llc_linktype(proto);
+               b1 = gen_llc_linktype(cstate, proto);
                gen_and(b0, b1);
                return b1;
                /*NOTREACHED*/
@@ -3002,7 +3016,7 @@ gen_linktype(proto)
                /*
                 * XXX - check for LLC frames.
                 */
-               return gen_llc_linktype(proto);
+               return gen_llc_linktype(cstate, proto);
                /*NOTREACHED*/
                break;
 
@@ -3010,14 +3024,14 @@ gen_linktype(proto)
                /*
                 * XXX - check for LLC PDUs, as per IEEE 802.5.
                 */
-               return gen_llc_linktype(proto);
+               return gen_llc_linktype(cstate, proto);
                /*NOTREACHED*/
                break;
 
        case DLT_ATM_RFC1483:
        case DLT_ATM_CLIP:
        case DLT_IP_OVER_FC:
-               return gen_llc_linktype(proto);
+               return gen_llc_linktype(cstate, proto);
                /*NOTREACHED*/
                break;
 
@@ -3029,15 +3043,15 @@ gen_linktype(proto)
                 *
                 * Check for LLC encapsulation and then check the protocol.
                 */
-               b0 = gen_atmfield_code(A_PROTOTYPE, PT_LLC, BPF_JEQ, 0);
-               b1 = gen_llc_linktype(proto);
+               b0 = gen_atmfield_code(cstate, A_PROTOTYPE, PT_LLC, BPF_JEQ, 0);
+               b1 = gen_llc_linktype(cstate, proto);
                gen_and(b0, b1);
                return b1;
                /*NOTREACHED*/
                break;
 
        case DLT_LINUX_SLL:
-               return gen_linux_sll_linktype(proto);
+               return gen_linux_sll_linktype(cstate, proto);
                /*NOTREACHED*/
                break;
 
@@ -3055,14 +3069,14 @@ gen_linktype(proto)
 
                case ETHERTYPE_IP:
                        /* Check for a version number of 4. */
-                       return gen_mcmp(OR_LINKHDR, 0, BPF_B, 0x40, 0xF0);
+                       return gen_mcmp(cstate, OR_LINKHDR, 0, BPF_B, 0x40, 0xF0);
 
                case ETHERTYPE_IPV6:
                        /* Check for a version number of 6. */
-                       return gen_mcmp(OR_LINKHDR, 0, BPF_B, 0x60, 0xF0);
+                       return gen_mcmp(cstate, OR_LINKHDR, 0, BPF_B, 0x60, 0xF0);
 
                default:
-                       return gen_false();             /* always false */
+                       return gen_false(cstate);       /* always false */
                }
                /*NOTREACHED*/
                break;
@@ -3072,10 +3086,10 @@ gen_linktype(proto)
                 * Raw IPv4, so no type field.
                 */
                if (proto == ETHERTYPE_IP)
-                       return gen_true();              /* always true */
+                       return gen_true(cstate);        /* always true */
 
                /* Checking for something other than IPv4; always false */
-               return gen_false();
+               return gen_false(cstate);
                /*NOTREACHED*/
                break;
 
@@ -3084,10 +3098,10 @@ gen_linktype(proto)
                 * Raw IPv6, so no type field.
                 */
                if (proto == ETHERTYPE_IPV6)
-                       return gen_true();              /* always true */
+                       return gen_true(cstate);        /* always true */
 
                /* Checking for something other than IPv6; always false */
-               return gen_false();
+               return gen_false(cstate);
                /*NOTREACHED*/
                break;
 
@@ -3100,7 +3114,7 @@ gen_linktype(proto)
                 * map them to the corresponding PPP protocol types.
                 */
                proto = ethertype_to_ppptype(proto);
-               return gen_cmp(OR_LINKTYPE, 0, BPF_H, (bpf_int32)proto);
+               return gen_cmp(cstate, OR_LINKTYPE, 0, BPF_H, (bpf_int32)proto);
                /*NOTREACHED*/
                break;
 
@@ -3116,16 +3130,16 @@ gen_linktype(proto)
                         * Also check for Van Jacobson-compressed IP.
                         * XXX - do this for other forms of PPP?
                         */
-                       b0 = gen_cmp(OR_LINKTYPE, 0, BPF_H, PPP_IP);
-                       b1 = gen_cmp(OR_LINKTYPE, 0, BPF_H, PPP_VJC);
+                       b0 = gen_cmp(cstate, OR_LINKTYPE, 0, BPF_H, PPP_IP);
+                       b1 = gen_cmp(cstate, OR_LINKTYPE, 0, BPF_H, PPP_VJC);
                        gen_or(b0, b1);
-                       b0 = gen_cmp(OR_LINKTYPE, 0, BPF_H, PPP_VJNC);
+                       b0 = gen_cmp(cstate, OR_LINKTYPE, 0, BPF_H, PPP_VJNC);
                        gen_or(b1, b0);
                        return b0;
 
                default:
                        proto = ethertype_to_ppptype(proto);
-                       return gen_cmp(OR_LINKTYPE, 0, BPF_H,
+                       return gen_cmp(cstate, OR_LINKTYPE, 0, BPF_H,
                                (bpf_int32)proto);
                }
                /*NOTREACHED*/
@@ -3174,10 +3188,10 @@ gen_linktype(proto)
                         * XXX - support those that have AF_ values
                         * #defined on this platform, at least?
                         */
-                       return gen_false();
+                       return gen_false(cstate);
                }
 
-               if (linktype == DLT_NULL || linktype == DLT_ENC) {
+               if (cstate->linktype == DLT_NULL || cstate->linktype == DLT_ENC) {
                        /*
                         * The AF_ value is in host byte order, but
                         * the BPF interpreter will convert it to
@@ -3190,11 +3204,11 @@ gen_linktype(proto)
                         * Then we run it through "htonl()", and
                         * generate code to compare against the result.
                         */
-                       if (bpf_pcap->rfile != NULL && bpf_pcap->swapped)
+                       if (cstate->bpf_pcap->rfile != NULL && cstate->bpf_pcap->swapped)
                                proto = SWAPLONG(proto);
                        proto = htonl(proto);
                }
-               return (gen_cmp(OR_LINKHDR, 0, BPF_W, (bpf_int32)proto));
+               return (gen_cmp(cstate, OR_LINKHDR, 0, BPF_W, (bpf_int32)proto));
 
 #ifdef HAVE_NET_PFVAR_H
        case DLT_PFLOG:
@@ -3203,13 +3217,13 @@ gen_linktype(proto)
                 * the packet.
                 */
                if (proto == ETHERTYPE_IP)
-                       return (gen_cmp(OR_LINKHDR, offsetof(struct pfloghdr, af),
+                       return (gen_cmp(cstate, OR_LINKHDR, offsetof(struct pfloghdr, af),
                            BPF_B, (bpf_int32)AF_INET));
                else if (proto == ETHERTYPE_IPV6)
-                       return (gen_cmp(OR_LINKHDR, offsetof(struct pfloghdr, af),
+                       return (gen_cmp(cstate, OR_LINKHDR, offsetof(struct pfloghdr, af),
                            BPF_B, (bpf_int32)AF_INET6));
                else
-                       return gen_false();
+                       return gen_false(cstate);
                /*NOTREACHED*/
                break;
 #endif /* HAVE_NET_PFVAR_H */
@@ -3223,34 +3237,34 @@ gen_linktype(proto)
                switch (proto) {
 
                default:
-                       return gen_false();
+                       return gen_false(cstate);
 
                case ETHERTYPE_IPV6:
-                       return (gen_cmp(OR_LINKTYPE, 0, BPF_B,
+                       return (gen_cmp(cstate, OR_LINKTYPE, 0, BPF_B,
                                (bpf_int32)ARCTYPE_INET6));
 
                case ETHERTYPE_IP:
-                       b0 = gen_cmp(OR_LINKTYPE, 0, BPF_B,
+                       b0 = gen_cmp(cstate, OR_LINKTYPE, 0, BPF_B,
                                     (bpf_int32)ARCTYPE_IP);
-                       b1 = gen_cmp(OR_LINKTYPE, 0, BPF_B,
+                       b1 = gen_cmp(cstate, OR_LINKTYPE, 0, BPF_B,
                                     (bpf_int32)ARCTYPE_IP_OLD);
                        gen_or(b0, b1);
                        return (b1);
 
                case ETHERTYPE_ARP:
-                       b0 = gen_cmp(OR_LINKTYPE, 0, BPF_B,
+                       b0 = gen_cmp(cstate, OR_LINKTYPE, 0, BPF_B,
                                     (bpf_int32)ARCTYPE_ARP);
-                       b1 = gen_cmp(OR_LINKTYPE, 0, BPF_B,
+                       b1 = gen_cmp(cstate, OR_LINKTYPE, 0, BPF_B,
                                     (bpf_int32)ARCTYPE_ARP_OLD);
                        gen_or(b0, b1);
                        return (b1);
 
                case ETHERTYPE_REVARP:
-                       return (gen_cmp(OR_LINKTYPE, 0, BPF_B,
+                       return (gen_cmp(cstate, OR_LINKTYPE, 0, BPF_B,
                                        (bpf_int32)ARCTYPE_REVARP));
 
                case ETHERTYPE_ATALK:
-                       return (gen_cmp(OR_LINKTYPE, 0, BPF_B,
+                       return (gen_cmp(cstate, OR_LINKTYPE, 0, BPF_B,
                                        (bpf_int32)ARCTYPE_ATALK));
                }
                /*NOTREACHED*/
@@ -3259,9 +3273,9 @@ gen_linktype(proto)
        case DLT_LTALK:
                switch (proto) {
                case ETHERTYPE_ATALK:
-                       return gen_true();
+                       return gen_true(cstate);
                default:
-                       return gen_false();
+                       return gen_false(cstate);
                }
                /*NOTREACHED*/
                break;
@@ -3277,13 +3291,13 @@ gen_linktype(proto)
                        /*
                         * Check for the special NLPID for IP.
                         */
-                       return gen_cmp(OR_LINKHDR, 2, BPF_H, (0x03<<8) | 0xcc);
+                       return gen_cmp(cstate, OR_LINKHDR, 2, BPF_H, (0x03<<8) | 0xcc);
 
                case ETHERTYPE_IPV6:
                        /*
                         * Check for the special NLPID for IPv6.
                         */
-                       return gen_cmp(OR_LINKHDR, 2, BPF_H, (0x03<<8) | 0x8e);
+                       return gen_cmp(cstate, OR_LINKHDR, 2, BPF_H, (0x03<<8) | 0x8e);
 
                case LLCSAP_ISONS:
                        /*
@@ -3297,21 +3311,21 @@ gen_linktype(proto)
                         * control field of UI, i.e. 0x03 followed
                         * by the NLPID.
                         */
-                       b0 = gen_cmp(OR_LINKHDR, 2, BPF_H, (0x03<<8) | ISO8473_CLNP);
-                       b1 = gen_cmp(OR_LINKHDR, 2, BPF_H, (0x03<<8) | ISO9542_ESIS);
-                       b2 = gen_cmp(OR_LINKHDR, 2, BPF_H, (0x03<<8) | ISO10589_ISIS);
+                       b0 = gen_cmp(cstate, OR_LINKHDR, 2, BPF_H, (0x03<<8) | ISO8473_CLNP);
+                       b1 = gen_cmp(cstate, OR_LINKHDR, 2, BPF_H, (0x03<<8) | ISO9542_ESIS);
+                       b2 = gen_cmp(cstate, OR_LINKHDR, 2, BPF_H, (0x03<<8) | ISO10589_ISIS);
                        gen_or(b1, b2);
                        gen_or(b0, b2);
                        return b2;
 
                default:
-                       return gen_false();
+                       return gen_false(cstate);
                }
                /*NOTREACHED*/
                break;
 
        case DLT_MFR:
-               bpf_error("Multi-link Frame Relay link-layer type filtering not implemented");
+               bpf_error(cstate, "Multi-link Frame Relay link-layer type filtering not implemented");
 
         case DLT_JUNIPER_MFR:
         case DLT_JUNIPER_MLFR:
@@ -3343,73 +3357,73 @@ gen_linktype(proto)
                 *
                 * FIXME encapsulation specific BPF_ filters
                 */
-               return gen_mcmp(OR_LINKHDR, 0, BPF_W, 0x4d474300, 0xffffff00); /* compare the magic number */
+               return gen_mcmp(cstate, OR_LINKHDR, 0, BPF_W, 0x4d474300, 0xffffff00); /* compare the magic number */
 
        case DLT_BACNET_MS_TP:
-               return gen_mcmp(OR_LINKHDR, 0, BPF_W, 0x55FF0000, 0xffff0000);
+               return gen_mcmp(cstate, OR_LINKHDR, 0, BPF_W, 0x55FF0000, 0xffff0000);
 
        case DLT_IPNET:
-               return gen_ipnet_linktype(proto);
+               return gen_ipnet_linktype(cstate, proto);
 
        case DLT_LINUX_IRDA:
-               bpf_error("IrDA link-layer type filtering not implemented");
+               bpf_error(cstate, "IrDA link-layer type filtering not implemented");
 
        case DLT_DOCSIS:
-               bpf_error("DOCSIS link-layer type filtering not implemented");
+               bpf_error(cstate, "DOCSIS link-layer type filtering not implemented");
 
        case DLT_MTP2:
        case DLT_MTP2_WITH_PHDR:
-               bpf_error("MTP2 link-layer type filtering not implemented");
+               bpf_error(cstate, "MTP2 link-layer type filtering not implemented");
 
        case DLT_ERF:
-               bpf_error("ERF link-layer type filtering not implemented");
+               bpf_error(cstate, "ERF link-layer type filtering not implemented");
 
        case DLT_PFSYNC:
-               bpf_error("PFSYNC link-layer type filtering not implemented");
+               bpf_error(cstate, "PFSYNC link-layer type filtering not implemented");
 
        case DLT_LINUX_LAPD:
-               bpf_error("LAPD link-layer type filtering not implemented");
+               bpf_error(cstate, "LAPD link-layer type filtering not implemented");
 
        case DLT_USB:
        case DLT_USB_LINUX:
        case DLT_USB_LINUX_MMAPPED:
-               bpf_error("USB link-layer type filtering not implemented");
+               bpf_error(cstate, "USB link-layer type filtering not implemented");
 
        case DLT_BLUETOOTH_HCI_H4:
        case DLT_BLUETOOTH_HCI_H4_WITH_PHDR:
-               bpf_error("Bluetooth link-layer type filtering not implemented");
+               bpf_error(cstate, "Bluetooth link-layer type filtering not implemented");
 
        case DLT_CAN20B:
        case DLT_CAN_SOCKETCAN:
-               bpf_error("CAN link-layer type filtering not implemented");
+               bpf_error(cstate, "CAN link-layer type filtering not implemented");
 
        case DLT_IEEE802_15_4:
        case DLT_IEEE802_15_4_LINUX:
        case DLT_IEEE802_15_4_NONASK_PHY:
        case DLT_IEEE802_15_4_NOFCS:
-               bpf_error("IEEE 802.15.4 link-layer type filtering not implemented");
+               bpf_error(cstate, "IEEE 802.15.4 link-layer type filtering not implemented");
 
        case DLT_IEEE802_16_MAC_CPS_RADIO:
-               bpf_error("IEEE 802.16 link-layer type filtering not implemented");
+               bpf_error(cstate, "IEEE 802.16 link-layer type filtering not implemented");
 
        case DLT_SITA:
-               bpf_error("SITA link-layer type filtering not implemented");
+               bpf_error(cstate, "SITA link-layer type filtering not implemented");
 
        case DLT_RAIF1:
-               bpf_error("RAIF1 link-layer type filtering not implemented");
+               bpf_error(cstate, "RAIF1 link-layer type filtering not implemented");
 
        case DLT_IPMB:
-               bpf_error("IPMB link-layer type filtering not implemented");
+               bpf_error(cstate, "IPMB link-layer type filtering not implemented");
 
        case DLT_AX25_KISS:
-               bpf_error("AX.25 link-layer type filtering not implemented");
+               bpf_error(cstate, "AX.25 link-layer type filtering not implemented");
 
        case DLT_NFLOG:
                /* Using the fixed-size NFLOG header it is possible to tell only
                 * the address family of the packet, other meaningful data is
                 * either missing or behind TLVs.
                 */
-               bpf_error("NFLOG link-layer type filtering not implemented");
+               bpf_error(cstate, "NFLOG link-layer type filtering not implemented");
 
        default:
                /*
@@ -3418,24 +3432,24 @@ gen_linktype(proto)
                 * so, off_linktype.constant_part will be the offset of that
                 * field in the packet; if not, it will be -1.
                 */
-               if (off_linktype.constant_part != (u_int)-1) {
+               if (cstate->off_linktype.constant_part != (u_int)-1) {
                        /*
                         * Yes; assume it's an Ethernet type.  (If
                         * it's not, it needs to be handled specially
                         * above.)
                         */
-                       return gen_cmp(OR_LINKTYPE, 0, BPF_H, (bpf_int32)proto);
+                       return gen_cmp(cstate, OR_LINKTYPE, 0, BPF_H, (bpf_int32)proto);
                } else {
                        /*
                         * No; report an error.
                         */
-                       description = pcap_datalink_val_to_description(linktype);
+                       description = pcap_datalink_val_to_description(cstate->linktype);
                        if (description != NULL) {
-                               bpf_error("%s link-layer type filtering not implemented",
+                               bpf_error(cstate, "%s link-layer type filtering not implemented",
                                    description);
                        } else {
-                               bpf_error("DLT %u link-layer type filtering not implemented",
-                                   linktype);
+                               bpf_error(cstate, "DLT %u link-layer type filtering not implemented",
+                                   cstate->linktype);
                        }
                }
                break;
@@ -3450,9 +3464,7 @@ gen_linktype(proto)
  * code and protocol type in the SNAP header.
  */
 static struct block *
-gen_snap(orgcode, ptype)
-       bpf_u_int32 orgcode;
-       bpf_u_int32 ptype;
+gen_snap(compiler_state_t *cstate, bpf_u_int32 orgcode, bpf_u_int32 ptype)
 {
        u_char snapblock[8];
 
@@ -3464,32 +3476,32 @@ gen_snap(orgcode, ptype)
        snapblock[5] = (orgcode >> 0);  /* lower 8 bits of organization code */
        snapblock[6] = (ptype >> 8);    /* upper 8 bits of protocol type */
        snapblock[7] = (ptype >> 0);    /* lower 8 bits of protocol type */
-       return gen_bcmp(OR_LLC, 0, 8, snapblock);
+       return gen_bcmp(cstate, OR_LLC, 0, 8, snapblock);
 }
 
 /*
  * Generate code to match frames with an LLC header.
  */
 struct block *
-gen_llc(void)
+gen_llc(compiler_state_t *cstate)
 {
        struct block *b0, *b1;
 
-       switch (linktype) {
+       switch (cstate->linktype) {
 
        case DLT_EN10MB:
                /*
                 * We check for an Ethernet type field less than
                 * 1500, which means it's an 802.3 length field.
                 */
-               b0 = gen_cmp_gt(OR_LINKTYPE, 0, BPF_H, ETHERMTU);
+               b0 = gen_cmp_gt(cstate, OR_LINKTYPE, 0, BPF_H, ETHERMTU);
                gen_not(b0);
 
                /*
                 * Now check for the purported DSAP and SSAP not being
                 * 0xFF, to rule out NetWare-over-802.3.
                 */
-               b1 = gen_cmp(OR_LLC, 0, BPF_H, (bpf_int32)0xFFFF);
+               b1 = gen_cmp(cstate, OR_LLC, 0, BPF_H, (bpf_int32)0xFFFF);
                gen_not(b1);
                gen_and(b0, b1);
                return b1;
@@ -3498,20 +3510,20 @@ gen_llc(void)
                /*
                 * We check for LLC traffic.
                 */
-               b0 = gen_atmtype_abbrev(A_LLC);
+               b0 = gen_atmtype_abbrev(cstate, A_LLC);
                return b0;
 
        case DLT_IEEE802:       /* Token Ring */
                /*
                 * XXX - check for LLC frames.
                 */
-               return gen_true();
+               return gen_true(cstate);
 
        case DLT_FDDI:
                /*
                 * XXX - check for LLC frames.
                 */
-               return gen_true();
+               return gen_true(cstate);
 
        case DLT_ATM_RFC1483:
                /*
@@ -3522,7 +3534,7 @@ gen_llc(void)
                 * way to check for that; the protocol used on the VC
                 * is negotiated out of band.
                 */
-               return gen_true();
+               return gen_true(cstate);
 
        case DLT_IEEE802_11:
        case DLT_PRISM_HEADER:
@@ -3532,17 +3544,17 @@ gen_llc(void)
                /*
                 * Check that we have a data frame.
                 */
-               b0 = gen_check_802_11_data_frame();
+               b0 = gen_check_802_11_data_frame(cstate);
                return b0;
 
        default:
-               bpf_error("'llc' not supported for linktype %d", linktype);
+               bpf_error(cstate, "'llc' not supported for linktype %d", cstate->linktype);
                /* NOTREACHED */
        }
 }
 
 struct block *
-gen_llc_i(void)
+gen_llc_i(compiler_state_t *cstate)
 {
        struct block *b0, *b1;
        struct slist *s;
@@ -3550,14 +3562,14 @@ gen_llc_i(void)
        /*
         * Check whether this is an LLC frame.
         */
-       b0 = gen_llc();
+       b0 = gen_llc(cstate);
 
        /*
         * Load the control byte and test the low-order bit; it must
         * be clear for I frames.
         */
-       s = gen_load_a(OR_LLC, 2, BPF_B);
-       b1 = new_block(JMP(BPF_JSET));
+       s = gen_load_a(cstate, OR_LLC, 2, BPF_B);
+       b1 = new_block(cstate, JMP(BPF_JSET));
        b1->s.k = 0x01;
        b1->stmts = s;
        gen_not(b1);
@@ -3566,75 +3578,75 @@ gen_llc_i(void)
 }
 
 struct block *
-gen_llc_s(void)
+gen_llc_s(compiler_state_t *cstate)
 {
        struct block *b0, *b1;
 
        /*
         * Check whether this is an LLC frame.
         */
-       b0 = gen_llc();
+       b0 = gen_llc(cstate);
 
        /*
         * Now compare the low-order 2 bit of the control byte against
         * the appropriate value for S frames.
         */
-       b1 = gen_mcmp(OR_LLC, 2, BPF_B, LLC_S_FMT, 0x03);
+       b1 = gen_mcmp(cstate, OR_LLC, 2, BPF_B, LLC_S_FMT, 0x03);
        gen_and(b0, b1);
        return b1;
 }
 
 struct block *
-gen_llc_u(void)
+gen_llc_u(compiler_state_t *cstate)
 {
        struct block *b0, *b1;
 
        /*
         * Check whether this is an LLC frame.
         */
-       b0 = gen_llc();
+       b0 = gen_llc(cstate);
 
        /*
         * Now compare the low-order 2 bit of the control byte against
         * the appropriate value for U frames.
         */
-       b1 = gen_mcmp(OR_LLC, 2, BPF_B, LLC_U_FMT, 0x03);
+       b1 = gen_mcmp(cstate, OR_LLC, 2, BPF_B, LLC_U_FMT, 0x03);
        gen_and(b0, b1);
        return b1;
 }
 
 struct block *
-gen_llc_s_subtype(bpf_u_int32 subtype)
+gen_llc_s_subtype(compiler_state_t *cstate, bpf_u_int32 subtype)
 {
        struct block *b0, *b1;
 
        /*
         * Check whether this is an LLC frame.
         */
-       b0 = gen_llc();
+       b0 = gen_llc(cstate);
 
        /*
         * Now check for an S frame with the appropriate type.
         */
-       b1 = gen_mcmp(OR_LLC, 2, BPF_B, subtype, LLC_S_CMD_MASK);
+       b1 = gen_mcmp(cstate, OR_LLC, 2, BPF_B, subtype, LLC_S_CMD_MASK);
        gen_and(b0, b1);
        return b1;
 }
 
 struct block *
-gen_llc_u_subtype(bpf_u_int32 subtype)
+gen_llc_u_subtype(compiler_state_t *cstate, bpf_u_int32 subtype)
 {
        struct block *b0, *b1;
 
        /*
         * Check whether this is an LLC frame.
         */
-       b0 = gen_llc();
+       b0 = gen_llc(cstate);
 
        /*
         * Now check for a U frame with the appropriate type.
         */
-       b1 = gen_mcmp(OR_LLC, 2, BPF_B, subtype, LLC_U_CMD_MASK);
+       b1 = gen_mcmp(cstate, OR_LLC, 2, BPF_B, subtype, LLC_U_CMD_MASK);
        gen_and(b0, b1);
        return b1;
 }
@@ -3652,8 +3664,7 @@ gen_llc_u_subtype(bpf_u_int32 subtype)
  * protocol ID in a SNAP header.
  */
 static struct block *
-gen_llc_linktype(proto)
-       int proto;
+gen_llc_linktype(compiler_state_t *cstate, int proto)
 {
        /*
         * XXX - handle token-ring variable-length header.
@@ -3668,7 +3679,7 @@ gen_llc_linktype(proto)
                 * SSAP, like this, or should we check just the
                 * DSAP, as we do for other SAP values?
                 */
-               return gen_cmp(OR_LLC, 0, BPF_H, (bpf_u_int32)
+               return gen_cmp(cstate, OR_LLC, 0, BPF_H, (bpf_u_int32)
                             ((proto << 8) | proto));
 
        case LLCSAP_IPX:
@@ -3676,7 +3687,7 @@ gen_llc_linktype(proto)
                 * XXX - are there ever SNAP frames for IPX on
                 * non-Ethernet 802.x networks?
                 */
-               return gen_cmp(OR_LLC, 0, BPF_B,
+               return gen_cmp(cstate, OR_LLC, 0, BPF_B,
                    (bpf_int32)LLCSAP_IPX);
 
        case ETHERTYPE_ATALK:
@@ -3689,7 +3700,7 @@ gen_llc_linktype(proto)
                 * XXX - check for an organization code of
                 * encapsulated Ethernet as well?
                 */
-               return gen_snap(0x080007, ETHERTYPE_ATALK);
+               return gen_snap(cstate, 0x080007, ETHERTYPE_ATALK);
 
        default:
                /*
@@ -3701,7 +3712,7 @@ gen_llc_linktype(proto)
                         * This is an LLC SAP value, so check
                         * the DSAP.
                         */
-                       return gen_cmp(OR_LLC, 0, BPF_B, (bpf_int32)proto);
+                       return gen_cmp(cstate, OR_LLC, 0, BPF_B, (bpf_int32)proto);
                } else {
                        /*
                         * This is an Ethernet type; we assume that it's
@@ -3716,23 +3727,20 @@ gen_llc_linktype(proto)
                         * organization code of 0x000000 (encapsulated
                         * Ethernet), we'd do
                         *
-                        *      return gen_snap(0x000000, proto);
+                        *      return gen_snap(cstate, 0x000000, proto);
                         *
                         * here; for now, we don't, as per the above.
                         * I don't know whether it's worth the extra CPU
                         * time to do the right check or not.
                         */
-                       return gen_cmp(OR_LLC, 6, BPF_H, (bpf_int32)proto);
+                       return gen_cmp(cstate, OR_LLC, 6, BPF_H, (bpf_int32)proto);
                }
        }
 }
 
 static struct block *
-gen_hostop(addr, mask, dir, proto, src_off, dst_off)
-       bpf_u_int32 addr;
-       bpf_u_int32 mask;
-       int dir, proto;
-       u_int src_off, dst_off;
+gen_hostop(compiler_state_t *cstate, bpf_u_int32 addr, bpf_u_int32 mask,
+    int dir, int proto, u_int src_off, u_int dst_off)
 {
        struct block *b0, *b1;
        u_int offset;
@@ -3748,34 +3756,31 @@ gen_hostop(addr, mask, dir, proto, src_off, dst_off)
                break;
 
        case Q_AND:
-               b0 = gen_hostop(addr, mask, Q_SRC, proto, src_off, dst_off);
-               b1 = gen_hostop(addr, mask, Q_DST, proto, src_off, dst_off);
+               b0 = gen_hostop(cstate, addr, mask, Q_SRC, proto, src_off, dst_off);
+               b1 = gen_hostop(cstate, addr, mask, Q_DST, proto, src_off, dst_off);
                gen_and(b0, b1);
                return b1;
 
        case Q_OR:
        case Q_DEFAULT:
-               b0 = gen_hostop(addr, mask, Q_SRC, proto, src_off, dst_off);
-               b1 = gen_hostop(addr, mask, Q_DST, proto, src_off, dst_off);
+               b0 = gen_hostop(cstate, addr, mask, Q_SRC, proto, src_off, dst_off);
+               b1 = gen_hostop(cstate, addr, mask, Q_DST, proto, src_off, dst_off);
                gen_or(b0, b1);
                return b1;
 
        default:
                abort();
        }
-       b0 = gen_linktype(proto);
-       b1 = gen_mcmp(OR_LINKPL, offset, BPF_W, (bpf_int32)addr, mask);
+       b0 = gen_linktype(cstate, proto);
+       b1 = gen_mcmp(cstate, OR_LINKPL, offset, BPF_W, (bpf_int32)addr, mask);
        gen_and(b0, b1);
        return b1;
 }
 
 #ifdef INET6
 static struct block *
-gen_hostop6(addr, mask, dir, proto, src_off, dst_off)
-       struct in6_addr *addr;
-       struct in6_addr *mask;
-       int dir, proto;
-       u_int src_off, dst_off;
+gen_hostop6(compiler_state_t *cstate, struct in6_addr *addr,
+    struct in6_addr *mask, int dir, int proto, u_int src_off, u_int dst_off)
 {
        struct block *b0, *b1;
        u_int offset;
@@ -3792,15 +3797,15 @@ gen_hostop6(addr, mask, dir, proto, src_off, dst_off)
                break;
 
        case Q_AND:
-               b0 = gen_hostop6(addr, mask, Q_SRC, proto, src_off, dst_off);
-               b1 = gen_hostop6(addr, mask, Q_DST, proto, src_off, dst_off);
+               b0 = gen_hostop6(cstate, addr, mask, Q_SRC, proto, src_off, dst_off);
+               b1 = gen_hostop6(cstate, addr, mask, Q_DST, proto, src_off, dst_off);
                gen_and(b0, b1);
                return b1;
 
        case Q_OR:
        case Q_DEFAULT:
-               b0 = gen_hostop6(addr, mask, Q_SRC, proto, src_off, dst_off);
-               b1 = gen_hostop6(addr, mask, Q_DST, proto, src_off, dst_off);
+               b0 = gen_hostop6(cstate, addr, mask, Q_SRC, proto, src_off, dst_off);
+               b1 = gen_hostop6(cstate, addr, mask, Q_DST, proto, src_off, dst_off);
                gen_or(b0, b1);
                return b1;
 
@@ -3810,68 +3815,66 @@ gen_hostop6(addr, mask, dir, proto, src_off, dst_off)
        /* this order is important */
        a = (u_int32_t *)addr;
        m = (u_int32_t *)mask;
-       b1 = gen_mcmp(OR_LINKPL, offset + 12, BPF_W, ntohl(a[3]), ntohl(m[3]));
-       b0 = gen_mcmp(OR_LINKPL, offset + 8, BPF_W, ntohl(a[2]), ntohl(m[2]));
+       b1 = gen_mcmp(cstate, OR_LINKPL, offset + 12, BPF_W, ntohl(a[3]), ntohl(m[3]));
+       b0 = gen_mcmp(cstate, OR_LINKPL, offset + 8, BPF_W, ntohl(a[2]), ntohl(m[2]));
        gen_and(b0, b1);
-       b0 = gen_mcmp(OR_LINKPL, offset + 4, BPF_W, ntohl(a[1]), ntohl(m[1]));
+       b0 = gen_mcmp(cstate, OR_LINKPL, offset + 4, BPF_W, ntohl(a[1]), ntohl(m[1]));
        gen_and(b0, b1);
-       b0 = gen_mcmp(OR_LINKPL, offset + 0, BPF_W, ntohl(a[0]), ntohl(m[0]));
+       b0 = gen_mcmp(cstate, OR_LINKPL, offset + 0, BPF_W, ntohl(a[0]), ntohl(m[0]));
        gen_and(b0, b1);
-       b0 = gen_linktype(proto);
+       b0 = gen_linktype(cstate, proto);
        gen_and(b0, b1);
        return b1;
 }
 #endif
 
 static struct block *
-gen_ehostop(eaddr, dir)
-       register const u_char *eaddr;
-       register int dir;
+gen_ehostop(compiler_state_t *cstate, const u_char *eaddr, int dir)
 {
        register struct block *b0, *b1;
 
        switch (dir) {
        case Q_SRC:
-               return gen_bcmp(OR_LINKHDR, 6, 6, eaddr);
+               return gen_bcmp(cstate, OR_LINKHDR, 6, 6, eaddr);
 
        case Q_DST:
-               return gen_bcmp(OR_LINKHDR, 0, 6, eaddr);
+               return gen_bcmp(cstate, OR_LINKHDR, 0, 6, eaddr);
 
        case Q_AND:
-               b0 = gen_ehostop(eaddr, Q_SRC);
-               b1 = gen_ehostop(eaddr, Q_DST);
+               b0 = gen_ehostop(cstate, eaddr, Q_SRC);
+               b1 = gen_ehostop(cstate, eaddr, Q_DST);
                gen_and(b0, b1);
                return b1;
 
        case Q_DEFAULT:
        case Q_OR:
-               b0 = gen_ehostop(eaddr, Q_SRC);
-               b1 = gen_ehostop(eaddr, Q_DST);
+               b0 = gen_ehostop(cstate, eaddr, Q_SRC);
+               b1 = gen_ehostop(cstate, eaddr, Q_DST);
                gen_or(b0, b1);
                return b1;
 
        case Q_ADDR1:
-               bpf_error("'addr1' is only supported on 802.11 with 802.11 headers");
+               bpf_error(cstate, "'addr1' is only supported on 802.11 with 802.11 headers");
                break;
 
        case Q_ADDR2:
-               bpf_error("'addr2' is only supported on 802.11 with 802.11 headers");
+               bpf_error(cstate, "'addr2' is only supported on 802.11 with 802.11 headers");
                break;
 
        case Q_ADDR3:
-               bpf_error("'addr3' is only supported on 802.11 with 802.11 headers");
+               bpf_error(cstate, "'addr3' is only supported on 802.11 with 802.11 headers");
                break;
 
        case Q_ADDR4:
-               bpf_error("'addr4' is only supported on 802.11 with 802.11 headers");
+               bpf_error(cstate, "'addr4' is only supported on 802.11 with 802.11 headers");
                break;
 
        case Q_RA:
-               bpf_error("'ra' is only supported on 802.11 with 802.11 headers");
+               bpf_error(cstate, "'ra' is only supported on 802.11 with 802.11 headers");
                break;
 
        case Q_TA:
-               bpf_error("'ta' is only supported on 802.11 with 802.11 headers");
+               bpf_error(cstate, "'ta' is only supported on 802.11 with 802.11 headers");
                break;
        }
        abort();
@@ -3882,54 +3885,52 @@ gen_ehostop(eaddr, dir)
  * Like gen_ehostop, but for DLT_FDDI
  */
 static struct block *
-gen_fhostop(eaddr, dir)
-       register const u_char *eaddr;
-       register int dir;
+gen_fhostop(compiler_state_t *cstate, const u_char *eaddr, int dir)
 {
        struct block *b0, *b1;
 
        switch (dir) {
        case Q_SRC:
-               return gen_bcmp(OR_LINKHDR, 6 + 1 + pcap_fddipad, 6, eaddr);
+               return gen_bcmp(cstate, OR_LINKHDR, 6 + 1 + cstate->pcap_fddipad, 6, eaddr);
 
        case Q_DST:
-               return gen_bcmp(OR_LINKHDR, 0 + 1 + pcap_fddipad, 6, eaddr);
+               return gen_bcmp(cstate, OR_LINKHDR, 0 + 1 + cstate->pcap_fddipad, 6, eaddr);
 
        case Q_AND:
-               b0 = gen_fhostop(eaddr, Q_SRC);
-               b1 = gen_fhostop(eaddr, Q_DST);
+               b0 = gen_fhostop(cstate, eaddr, Q_SRC);
+               b1 = gen_fhostop(cstate, eaddr, Q_DST);
                gen_and(b0, b1);
                return b1;
 
        case Q_DEFAULT:
        case Q_OR:
-               b0 = gen_fhostop(eaddr, Q_SRC);
-               b1 = gen_fhostop(eaddr, Q_DST);
+               b0 = gen_fhostop(cstate, eaddr, Q_SRC);
+               b1 = gen_fhostop(cstate, eaddr, Q_DST);
                gen_or(b0, b1);
                return b1;
 
        case Q_ADDR1:
-               bpf_error("'addr1' is only supported on 802.11");
+               bpf_error(cstate, "'addr1' is only supported on 802.11");
                break;
 
        case Q_ADDR2:
-               bpf_error("'addr2' is only supported on 802.11");
+               bpf_error(cstate, "'addr2' is only supported on 802.11");
                break;
 
        case Q_ADDR3:
-               bpf_error("'addr3' is only supported on 802.11");
+               bpf_error(cstate, "'addr3' is only supported on 802.11");
                break;
 
        case Q_ADDR4:
-               bpf_error("'addr4' is only supported on 802.11");
+               bpf_error(cstate, "'addr4' is only supported on 802.11");
                break;
 
        case Q_RA:
-               bpf_error("'ra' is only supported on 802.11");
+               bpf_error(cstate, "'ra' is only supported on 802.11");
                break;
 
        case Q_TA:
-               bpf_error("'ta' is only supported on 802.11");
+               bpf_error(cstate, "'ta' is only supported on 802.11");
                break;
        }
        abort();
@@ -3940,54 +3941,52 @@ gen_fhostop(eaddr, dir)
  * Like gen_ehostop, but for DLT_IEEE802 (Token Ring)
  */
 static struct block *
-gen_thostop(eaddr, dir)
-       register const u_char *eaddr;
-       register int dir;
+gen_thostop(compiler_state_t *cstate, const u_char *eaddr, int dir)
 {
        register struct block *b0, *b1;
 
        switch (dir) {
        case Q_SRC:
-               return gen_bcmp(OR_LINKHDR, 8, 6, eaddr);
+               return gen_bcmp(cstate, OR_LINKHDR, 8, 6, eaddr);
 
        case Q_DST:
-               return gen_bcmp(OR_LINKHDR, 2, 6, eaddr);
+               return gen_bcmp(cstate, OR_LINKHDR, 2, 6, eaddr);
 
        case Q_AND:
-               b0 = gen_thostop(eaddr, Q_SRC);
-               b1 = gen_thostop(eaddr, Q_DST);
+               b0 = gen_thostop(cstate, eaddr, Q_SRC);
+               b1 = gen_thostop(cstate, eaddr, Q_DST);
                gen_and(b0, b1);
                return b1;
 
        case Q_DEFAULT:
        case Q_OR:
-               b0 = gen_thostop(eaddr, Q_SRC);
-               b1 = gen_thostop(eaddr, Q_DST);
+               b0 = gen_thostop(cstate, eaddr, Q_SRC);
+               b1 = gen_thostop(cstate, eaddr, Q_DST);
                gen_or(b0, b1);
                return b1;
 
        case Q_ADDR1:
-               bpf_error("'addr1' is only supported on 802.11");
+               bpf_error(cstate, "'addr1' is only supported on 802.11");
                break;
 
        case Q_ADDR2:
-               bpf_error("'addr2' is only supported on 802.11");
+               bpf_error(cstate, "'addr2' is only supported on 802.11");
                break;
 
        case Q_ADDR3:
-               bpf_error("'addr3' is only supported on 802.11");
+               bpf_error(cstate, "'addr3' is only supported on 802.11");
                break;
 
        case Q_ADDR4:
-               bpf_error("'addr4' is only supported on 802.11");
+               bpf_error(cstate, "'addr4' is only supported on 802.11");
                break;
 
        case Q_RA:
-               bpf_error("'ra' is only supported on 802.11");
+               bpf_error(cstate, "'ra' is only supported on 802.11");
                break;
 
        case Q_TA:
-               bpf_error("'ta' is only supported on 802.11");
+               bpf_error(cstate, "'ta' is only supported on 802.11");
                break;
        }
        abort();
@@ -3999,9 +3998,7 @@ gen_thostop(eaddr, dir)
  * various 802.11 + radio headers.
  */
 static struct block *
-gen_wlanhostop(eaddr, dir)
-       register const u_char *eaddr;
-       register int dir;
+gen_wlanhostop(compiler_state_t *cstate, const u_char *eaddr, int dir)
 {
        register struct block *b0, *b1, *b2;
        register struct slist *s;
@@ -4013,7 +4010,7 @@ gen_wlanhostop(eaddr, dir)
         * and wipes out some LD instructions generated by the below
         * code to validate the Frame Control bits
         */
-       no_optimize = 1;
+       cstate->no_optimize = 1;
 #endif /* ENABLE_WLAN_FILTERING_PATCH */
 
        switch (dir) {
@@ -4043,23 +4040,23 @@ gen_wlanhostop(eaddr, dir)
                 *
                 * First, check for To DS set, i.e. check "link[1] & 0x01".
                 */
-               s = gen_load_a(OR_LINKHDR, 1, BPF_B);
-               b1 = new_block(JMP(BPF_JSET));
+               s = gen_load_a(cstate, OR_LINKHDR, 1, BPF_B);
+               b1 = new_block(cstate, JMP(BPF_JSET));
                b1->s.k = 0x01; /* To DS */
                b1->stmts = s;
 
                /*
                 * If To DS is set, the SA is at 24.
                 */
-               b0 = gen_bcmp(OR_LINKHDR, 24, 6, eaddr);
+               b0 = gen_bcmp(cstate, OR_LINKHDR, 24, 6, eaddr);
                gen_and(b1, b0);
 
                /*
                 * Now, check for To DS not set, i.e. check
                 * "!(link[1] & 0x01)".
                 */
-               s = gen_load_a(OR_LINKHDR, 1, BPF_B);
-               b2 = new_block(JMP(BPF_JSET));
+               s = gen_load_a(cstate, OR_LINKHDR, 1, BPF_B);
+               b2 = new_block(cstate, JMP(BPF_JSET));
                b2->s.k = 0x01; /* To DS */
                b2->stmts = s;
                gen_not(b2);
@@ -4067,7 +4064,7 @@ gen_wlanhostop(eaddr, dir)
                /*
                 * If To DS is not set, the SA is at 16.
                 */
-               b1 = gen_bcmp(OR_LINKHDR, 16, 6, eaddr);
+               b1 = gen_bcmp(cstate, OR_LINKHDR, 16, 6, eaddr);
                gen_and(b2, b1);
 
                /*
@@ -4081,8 +4078,8 @@ gen_wlanhostop(eaddr, dir)
                 * Now check for From DS being set, and AND that with
                 * the ORed-together checks.
                 */
-               s = gen_load_a(OR_LINKHDR, 1, BPF_B);
-               b1 = new_block(JMP(BPF_JSET));
+               s = gen_load_a(cstate, OR_LINKHDR, 1, BPF_B);
+               b1 = new_block(cstate, JMP(BPF_JSET));
                b1->s.k = 0x02; /* From DS */
                b1->stmts = s;
                gen_and(b1, b0);
@@ -4090,8 +4087,8 @@ gen_wlanhostop(eaddr, dir)
                /*
                 * Now check for data frames with From DS not set.
                 */
-               s = gen_load_a(OR_LINKHDR, 1, BPF_B);
-               b2 = new_block(JMP(BPF_JSET));
+               s = gen_load_a(cstate, OR_LINKHDR, 1, BPF_B);
+               b2 = new_block(cstate, JMP(BPF_JSET));
                b2->s.k = 0x02; /* From DS */
                b2->stmts = s;
                gen_not(b2);
@@ -4099,7 +4096,7 @@ gen_wlanhostop(eaddr, dir)
                /*
                 * If From DS isn't set, the SA is at 10.
                 */
-               b1 = gen_bcmp(OR_LINKHDR, 10, 6, eaddr);
+               b1 = gen_bcmp(cstate, OR_LINKHDR, 10, 6, eaddr);
                gen_and(b2, b1);
 
                /*
@@ -4113,8 +4110,8 @@ gen_wlanhostop(eaddr, dir)
                 * Now check for a data frame.
                 * I.e, check "link[0] & 0x08".
                 */
-               s = gen_load_a(OR_LINKHDR, 0, BPF_B);
-               b1 = new_block(JMP(BPF_JSET));
+               s = gen_load_a(cstate, OR_LINKHDR, 0, BPF_B);
+               b1 = new_block(cstate, JMP(BPF_JSET));
                b1->s.k = 0x08;
                b1->stmts = s;
 
@@ -4128,8 +4125,8 @@ gen_wlanhostop(eaddr, dir)
                 * is a management frame.
                 * I.e, check "!(link[0] & 0x08)".
                 */
-               s = gen_load_a(OR_LINKHDR, 0, BPF_B);
-               b2 = new_block(JMP(BPF_JSET));
+               s = gen_load_a(cstate, OR_LINKHDR, 0, BPF_B);
+               b2 = new_block(cstate, JMP(BPF_JSET));
                b2->s.k = 0x08;
                b2->stmts = s;
                gen_not(b2);
@@ -4137,7 +4134,7 @@ gen_wlanhostop(eaddr, dir)
                /*
                 * For management frames, the SA is at 10.
                 */
-               b1 = gen_bcmp(OR_LINKHDR, 10, 6, eaddr);
+               b1 = gen_bcmp(cstate, OR_LINKHDR, 10, 6, eaddr);
                gen_and(b2, b1);
 
                /*
@@ -4155,8 +4152,8 @@ gen_wlanhostop(eaddr, dir)
                 *
                 * I.e., check "!(link[0] & 0x04)".
                 */
-               s = gen_load_a(OR_LINKHDR, 0, BPF_B);
-               b1 = new_block(JMP(BPF_JSET));
+               s = gen_load_a(cstate, OR_LINKHDR, 0, BPF_B);
+               b1 = new_block(cstate, JMP(BPF_JSET));
                b1->s.k = 0x04;
                b1->stmts = s;
                gen_not(b1);
@@ -4190,23 +4187,23 @@ gen_wlanhostop(eaddr, dir)
                 *
                 * First, check for To DS set, i.e. "link[1] & 0x01".
                 */
-               s = gen_load_a(OR_LINKHDR, 1, BPF_B);
-               b1 = new_block(JMP(BPF_JSET));
+               s = gen_load_a(cstate, OR_LINKHDR, 1, BPF_B);
+               b1 = new_block(cstate, JMP(BPF_JSET));
                b1->s.k = 0x01; /* To DS */
                b1->stmts = s;
 
                /*
                 * If To DS is set, the DA is at 16.
                 */
-               b0 = gen_bcmp(OR_LINKHDR, 16, 6, eaddr);
+               b0 = gen_bcmp(cstate, OR_LINKHDR, 16, 6, eaddr);
                gen_and(b1, b0);
 
                /*
                 * Now, check for To DS not set, i.e. check
                 * "!(link[1] & 0x01)".
                 */
-               s = gen_load_a(OR_LINKHDR, 1, BPF_B);
-               b2 = new_block(JMP(BPF_JSET));
+               s = gen_load_a(cstate, OR_LINKHDR, 1, BPF_B);
+               b2 = new_block(cstate, JMP(BPF_JSET));
                b2->s.k = 0x01; /* To DS */
                b2->stmts = s;
                gen_not(b2);
@@ -4214,7 +4211,7 @@ gen_wlanhostop(eaddr, dir)
                /*
                 * If To DS is not set, the DA is at 4.
                 */
-               b1 = gen_bcmp(OR_LINKHDR, 4, 6, eaddr);
+               b1 = gen_bcmp(cstate, OR_LINKHDR, 4, 6, eaddr);
                gen_and(b2, b1);
 
                /*
@@ -4227,8 +4224,8 @@ gen_wlanhostop(eaddr, dir)
                 * Now check for a data frame.
                 * I.e, check "link[0] & 0x08".
                 */
-               s = gen_load_a(OR_LINKHDR, 0, BPF_B);
-               b1 = new_block(JMP(BPF_JSET));
+               s = gen_load_a(cstate, OR_LINKHDR, 0, BPF_B);
+               b1 = new_block(cstate, JMP(BPF_JSET));
                b1->s.k = 0x08;
                b1->stmts = s;
 
@@ -4242,8 +4239,8 @@ gen_wlanhostop(eaddr, dir)
                 * is a management frame.
                 * I.e, check "!(link[0] & 0x08)".
                 */
-               s = gen_load_a(OR_LINKHDR, 0, BPF_B);
-               b2 = new_block(JMP(BPF_JSET));
+               s = gen_load_a(cstate, OR_LINKHDR, 0, BPF_B);
+               b2 = new_block(cstate, JMP(BPF_JSET));
                b2->s.k = 0x08;
                b2->stmts = s;
                gen_not(b2);
@@ -4251,7 +4248,7 @@ gen_wlanhostop(eaddr, dir)
                /*
                 * For management frames, the DA is at 4.
                 */
-               b1 = gen_bcmp(OR_LINKHDR, 4, 6, eaddr);
+               b1 = gen_bcmp(cstate, OR_LINKHDR, 4, 6, eaddr);
                gen_and(b2, b1);
 
                /*
@@ -4269,8 +4266,8 @@ gen_wlanhostop(eaddr, dir)
                 *
                 * I.e., check "!(link[0] & 0x04)".
                 */
-               s = gen_load_a(OR_LINKHDR, 0, BPF_B);
-               b1 = new_block(JMP(BPF_JSET));
+               s = gen_load_a(cstate, OR_LINKHDR, 0, BPF_B);
+               b1 = new_block(cstate, JMP(BPF_JSET));
                b1->s.k = 0x04;
                b1->stmts = s;
                gen_not(b1);
@@ -4293,15 +4290,15 @@ gen_wlanhostop(eaddr, dir)
                 * is a management frame.
                 * I.e, check "(link[0] & 0x08)".
                 */
-               s = gen_load_a(OR_LINKHDR, 0, BPF_B);
-               b1 = new_block(JMP(BPF_JSET));
+               s = gen_load_a(cstate, OR_LINKHDR, 0, BPF_B);
+               b1 = new_block(cstate, JMP(BPF_JSET));
                b1->s.k = 0x08;
                b1->stmts = s;
 
                /*
                 * Check addr1.
                 */
-               b0 = gen_bcmp(OR_LINKHDR, 4, 6, eaddr);
+               b0 = gen_bcmp(cstate, OR_LINKHDR, 4, 6, eaddr);
 
                /*
                 * AND that with the check of addr1.
@@ -4318,13 +4315,13 @@ gen_wlanhostop(eaddr, dir)
                /*
                 * Not present in CTS or ACK control frames.
                 */
-               b0 = gen_mcmp(OR_LINKHDR, 0, BPF_B, IEEE80211_FC0_TYPE_CTL,
+               b0 = gen_mcmp(cstate, OR_LINKHDR, 0, BPF_B, IEEE80211_FC0_TYPE_CTL,
                        IEEE80211_FC0_TYPE_MASK);
                gen_not(b0);
-               b1 = gen_mcmp(OR_LINKHDR, 0, BPF_B, IEEE80211_FC0_SUBTYPE_CTS,
+               b1 = gen_mcmp(cstate, OR_LINKHDR, 0, BPF_B, IEEE80211_FC0_SUBTYPE_CTS,
                        IEEE80211_FC0_SUBTYPE_MASK);
                gen_not(b1);
-               b2 = gen_mcmp(OR_LINKHDR, 0, BPF_B, IEEE80211_FC0_SUBTYPE_ACK,
+               b2 = gen_mcmp(cstate, OR_LINKHDR, 0, BPF_B, IEEE80211_FC0_SUBTYPE_ACK,
                        IEEE80211_FC0_SUBTYPE_MASK);
                gen_not(b2);
                gen_and(b1, b2);
@@ -4335,8 +4332,8 @@ gen_wlanhostop(eaddr, dir)
                 * is a management frame.
                 * I.e, check "(link[0] & 0x08)".
                 */
-               s = gen_load_a(OR_LINKHDR, 0, BPF_B);
-               b1 = new_block(JMP(BPF_JSET));
+               s = gen_load_a(cstate, OR_LINKHDR, 0, BPF_B);
+               b1 = new_block(cstate, JMP(BPF_JSET));
                b1->s.k = 0x08;
                b1->stmts = s;
 
@@ -4349,7 +4346,7 @@ gen_wlanhostop(eaddr, dir)
                /*
                 * Check addr2.
                 */
-               b1 = gen_bcmp(OR_LINKHDR, 10, 6, eaddr);
+               b1 = gen_bcmp(cstate, OR_LINKHDR, 10, 6, eaddr);
                gen_and(b2, b1);
                return b1;
 
@@ -4357,24 +4354,24 @@ gen_wlanhostop(eaddr, dir)
         * XXX - add BSSID keyword?
         */
        case Q_ADDR1:
-               return (gen_bcmp(OR_LINKHDR, 4, 6, eaddr));
+               return (gen_bcmp(cstate, OR_LINKHDR, 4, 6, eaddr));
 
        case Q_ADDR2:
                /*
                 * Not present in CTS or ACK control frames.
                 */
-               b0 = gen_mcmp(OR_LINKHDR, 0, BPF_B, IEEE80211_FC0_TYPE_CTL,
+               b0 = gen_mcmp(cstate, OR_LINKHDR, 0, BPF_B, IEEE80211_FC0_TYPE_CTL,
                        IEEE80211_FC0_TYPE_MASK);
                gen_not(b0);
-               b1 = gen_mcmp(OR_LINKHDR, 0, BPF_B, IEEE80211_FC0_SUBTYPE_CTS,
+               b1 = gen_mcmp(cstate, OR_LINKHDR, 0, BPF_B, IEEE80211_FC0_SUBTYPE_CTS,
                        IEEE80211_FC0_SUBTYPE_MASK);
                gen_not(b1);
-               b2 = gen_mcmp(OR_LINKHDR, 0, BPF_B, IEEE80211_FC0_SUBTYPE_ACK,
+               b2 = gen_mcmp(cstate, OR_LINKHDR, 0, BPF_B, IEEE80211_FC0_SUBTYPE_ACK,
                        IEEE80211_FC0_SUBTYPE_MASK);
                gen_not(b2);
                gen_and(b1, b2);
                gen_or(b0, b2);
-               b1 = gen_bcmp(OR_LINKHDR, 10, 6, eaddr);
+               b1 = gen_bcmp(cstate, OR_LINKHDR, 10, 6, eaddr);
                gen_and(b2, b1);
                return b1;
 
@@ -4382,10 +4379,10 @@ gen_wlanhostop(eaddr, dir)
                /*
                 * Not present in control frames.
                 */
-               b0 = gen_mcmp(OR_LINKHDR, 0, BPF_B, IEEE80211_FC0_TYPE_CTL,
+               b0 = gen_mcmp(cstate, OR_LINKHDR, 0, BPF_B, IEEE80211_FC0_TYPE_CTL,
                        IEEE80211_FC0_TYPE_MASK);
                gen_not(b0);
-               b1 = gen_bcmp(OR_LINKHDR, 16, 6, eaddr);
+               b1 = gen_bcmp(cstate, OR_LINKHDR, 16, 6, eaddr);
                gen_and(b0, b1);
                return b1;
 
@@ -4396,22 +4393,22 @@ gen_wlanhostop(eaddr, dir)
                 * frames should have both of those set, so we don't
                 * check the frame type.
                 */
-               b0 = gen_mcmp(OR_LINKHDR, 1, BPF_B,
+               b0 = gen_mcmp(cstate, OR_LINKHDR, 1, BPF_B,
                        IEEE80211_FC1_DIR_DSTODS, IEEE80211_FC1_DIR_MASK);
-               b1 = gen_bcmp(OR_LINKHDR, 24, 6, eaddr);
+               b1 = gen_bcmp(cstate, OR_LINKHDR, 24, 6, eaddr);
                gen_and(b0, b1);
                return b1;
 
        case Q_AND:
-               b0 = gen_wlanhostop(eaddr, Q_SRC);
-               b1 = gen_wlanhostop(eaddr, Q_DST);
+               b0 = gen_wlanhostop(cstate, eaddr, Q_SRC);
+               b1 = gen_wlanhostop(cstate, eaddr, Q_DST);
                gen_and(b0, b1);
                return b1;
 
        case Q_DEFAULT:
        case Q_OR:
-               b0 = gen_wlanhostop(eaddr, Q_SRC);
-               b1 = gen_wlanhostop(eaddr, Q_DST);
+               b0 = gen_wlanhostop(cstate, eaddr, Q_SRC);
+               b1 = gen_wlanhostop(cstate, eaddr, Q_DST);
                gen_or(b0, b1);
                return b1;
        }
@@ -4425,54 +4422,52 @@ gen_wlanhostop(eaddr, dir)
  * as the RFC states.)
  */
 static struct block *
-gen_ipfchostop(eaddr, dir)
-       register const u_char *eaddr;
-       register int dir;
+gen_ipfchostop(compiler_state_t *cstate, const u_char *eaddr, int dir)
 {
        register struct block *b0, *b1;
 
        switch (dir) {
        case Q_SRC:
-               return gen_bcmp(OR_LINKHDR, 10, 6, eaddr);
+               return gen_bcmp(cstate, OR_LINKHDR, 10, 6, eaddr);
 
        case Q_DST:
-               return gen_bcmp(OR_LINKHDR, 2, 6, eaddr);
+               return gen_bcmp(cstate, OR_LINKHDR, 2, 6, eaddr);
 
        case Q_AND:
-               b0 = gen_ipfchostop(eaddr, Q_SRC);
-               b1 = gen_ipfchostop(eaddr, Q_DST);
+               b0 = gen_ipfchostop(cstate, eaddr, Q_SRC);
+               b1 = gen_ipfchostop(cstate, eaddr, Q_DST);
                gen_and(b0, b1);
                return b1;
 
        case Q_DEFAULT:
        case Q_OR:
-               b0 = gen_ipfchostop(eaddr, Q_SRC);
-               b1 = gen_ipfchostop(eaddr, Q_DST);
+               b0 = gen_ipfchostop(cstate, eaddr, Q_SRC);
+               b1 = gen_ipfchostop(cstate, eaddr, Q_DST);
                gen_or(b0, b1);
                return b1;
 
        case Q_ADDR1:
-               bpf_error("'addr1' is only supported on 802.11");
+               bpf_error(cstate, "'addr1' is only supported on 802.11");
                break;
 
        case Q_ADDR2:
-               bpf_error("'addr2' is only supported on 802.11");
+               bpf_error(cstate, "'addr2' is only supported on 802.11");
                break;
 
        case Q_ADDR3:
-               bpf_error("'addr3' is only supported on 802.11");
+               bpf_error(cstate, "'addr3' is only supported on 802.11");
                break;
 
        case Q_ADDR4:
-               bpf_error("'addr4' is only supported on 802.11");
+               bpf_error(cstate, "'addr4' is only supported on 802.11");
                break;
 
        case Q_RA:
-               bpf_error("'ra' is only supported on 802.11");
+               bpf_error(cstate, "'ra' is only supported on 802.11");
                break;
 
        case Q_TA:
-               bpf_error("'ta' is only supported on 802.11");
+               bpf_error(cstate, "'ta' is only supported on 802.11");
                break;
        }
        abort();
@@ -4498,9 +4493,7 @@ gen_ipfchostop(eaddr, dir)
  * and not generate masking instructions if the mask is 0xFFFF.
  */
 static struct block *
-gen_dnhostop(addr, dir)
-       bpf_u_int32 addr;
-       int dir;
+gen_dnhostop(compiler_state_t *cstate, bpf_u_int32 addr, int dir)
 {
        struct block *b0, *b1, *b2, *tmp;
        u_int offset_lh;        /* offset if long header is received */
@@ -4520,50 +4513,50 @@ gen_dnhostop(addr, dir)
 
        case Q_AND:
                /* Inefficient because we do our Calvinball dance twice */
-               b0 = gen_dnhostop(addr, Q_SRC);
-               b1 = gen_dnhostop(addr, Q_DST);
+               b0 = gen_dnhostop(cstate, addr, Q_SRC);
+               b1 = gen_dnhostop(cstate, addr, Q_DST);
                gen_and(b0, b1);
                return b1;
 
        case Q_OR:
        case Q_DEFAULT:
                /* Inefficient because we do our Calvinball dance twice */
-               b0 = gen_dnhostop(addr, Q_SRC);
-               b1 = gen_dnhostop(addr, Q_DST);
+               b0 = gen_dnhostop(cstate, addr, Q_SRC);
+               b1 = gen_dnhostop(cstate, addr, Q_DST);
                gen_or(b0, b1);
                return b1;
 
        case Q_ISO:
-               bpf_error("ISO host filtering not implemented");
+               bpf_error(cstate, "ISO host filtering not implemented");
 
        default:
                abort();
        }
-       b0 = gen_linktype(ETHERTYPE_DN);
+       b0 = gen_linktype(cstate, ETHERTYPE_DN);
        /* Check for pad = 1, long header case */
-       tmp = gen_mcmp(OR_LINKPL, 2, BPF_H,
+       tmp = gen_mcmp(cstate, OR_LINKPL, 2, BPF_H,
            (bpf_int32)ntohs(0x0681), (bpf_int32)ntohs(0x07FF));
-       b1 = gen_cmp(OR_LINKPL, 2 + 1 + offset_lh,
+       b1 = gen_cmp(cstate, OR_LINKPL, 2 + 1 + offset_lh,
            BPF_H, (bpf_int32)ntohs((u_short)addr));
        gen_and(tmp, b1);
        /* Check for pad = 0, long header case */
-       tmp = gen_mcmp(OR_LINKPL, 2, BPF_B, (bpf_int32)0x06, (bpf_int32)0x7);
-       b2 = gen_cmp(OR_LINKPL, 2 + offset_lh, BPF_H, (bpf_int32)ntohs((u_short)addr));
+       tmp = gen_mcmp(cstate, OR_LINKPL, 2, BPF_B, (bpf_int32)0x06, (bpf_int32)0x7);
+       b2 = gen_cmp(cstate, OR_LINKPL, 2 + offset_lh, BPF_H, (bpf_int32)ntohs((u_short)addr));
        gen_and(tmp, b2);
        gen_or(b2, b1);
        /* Check for pad = 1, short header case */
-       tmp = gen_mcmp(OR_LINKPL, 2, BPF_H,
+       tmp = gen_mcmp(cstate, OR_LINKPL, 2, BPF_H,
            (bpf_int32)ntohs(0x0281), (bpf_int32)ntohs(0x07FF));
-       b2 = gen_cmp(OR_LINKPL, 2 + 1 + offset_sh, BPF_H, (bpf_int32)ntohs((u_short)addr));
+       b2 = gen_cmp(cstate, OR_LINKPL, 2 + 1 + offset_sh, BPF_H, (bpf_int32)ntohs((u_short)addr));
        gen_and(tmp, b2);
        gen_or(b2, b1);
        /* Check for pad = 0, short header case */
-       tmp = gen_mcmp(OR_LINKPL, 2, BPF_B, (bpf_int32)0x02, (bpf_int32)0x7);
-       b2 = gen_cmp(OR_LINKPL, 2 + offset_sh, BPF_H, (bpf_int32)ntohs((u_short)addr));
+       tmp = gen_mcmp(cstate, OR_LINKPL, 2, BPF_B, (bpf_int32)0x02, (bpf_int32)0x7);
+       b2 = gen_cmp(cstate, OR_LINKPL, 2 + offset_sh, BPF_H, (bpf_int32)ntohs((u_short)addr));
        gen_and(tmp, b2);
        gen_or(b2, b1);
 
-       /* Combine with test for linktype */
+       /* Combine with test for cstate->linktype */
        gen_and(b0, b1);
        return b1;
 }
@@ -4574,8 +4567,7 @@ gen_dnhostop(addr, dir)
  * field in the IP header.
  */
 static struct block *
-gen_mpls_linktype(proto)
-       int proto;
+gen_mpls_linktype(compiler_state_t *cstate, int proto)
 {
        struct block *b0, *b1;
 
@@ -4583,17 +4575,17 @@ gen_mpls_linktype(proto)
 
         case Q_IP:
                 /* match the bottom-of-stack bit */
-                b0 = gen_mcmp(OR_LINKPL, -2, BPF_B, 0x01, 0x01);
+                b0 = gen_mcmp(cstate, OR_LINKPL, -2, BPF_B, 0x01, 0x01);
                 /* match the IPv4 version number */
-                b1 = gen_mcmp(OR_LINKPL, 0, BPF_B, 0x40, 0xf0);
+                b1 = gen_mcmp(cstate, OR_LINKPL, 0, BPF_B, 0x40, 0xf0);
                 gen_and(b0, b1);
                 return b1;
 
        case Q_IPV6:
                 /* match the bottom-of-stack bit */
-                b0 = gen_mcmp(OR_LINKPL, -2, BPF_B, 0x01, 0x01);
+                b0 = gen_mcmp(cstate, OR_LINKPL, -2, BPF_B, 0x01, 0x01);
                 /* match the IPv4 version number */
-                b1 = gen_mcmp(OR_LINKPL, 0, BPF_B, 0x60, 0xf0);
+                b1 = gen_mcmp(cstate, OR_LINKPL, 0, BPF_B, 0x60, 0xf0);
                 gen_and(b0, b1);
                 return b1;
 
@@ -4603,12 +4595,8 @@ gen_mpls_linktype(proto)
 }
 
 static struct block *
-gen_host(addr, mask, proto, dir, type)
-       bpf_u_int32 addr;
-       bpf_u_int32 mask;
-       int proto;
-       int dir;
-       int type;
+gen_host(compiler_state_t *cstate, bpf_u_int32 addr, bpf_u_int32 mask,
+    int proto, int dir, int type)
 {
        struct block *b0, *b1;
        const char *typestr;
@@ -4621,111 +4609,111 @@ gen_host(addr, mask, proto, dir, type)
        switch (proto) {
 
        case Q_DEFAULT:
-               b0 = gen_host(addr, mask, Q_IP, dir, type);
+               b0 = gen_host(cstate, addr, mask, Q_IP, dir, type);
                /*
                 * Only check for non-IPv4 addresses if we're not
                 * checking MPLS-encapsulated packets.
                 */
-               if (label_stack_depth == 0) {
-                       b1 = gen_host(addr, mask, Q_ARP, dir, type);
+               if (cstate->label_stack_depth == 0) {
+                       b1 = gen_host(cstate, addr, mask, Q_ARP, dir, type);
                        gen_or(b0, b1);
-                       b0 = gen_host(addr, mask, Q_RARP, dir, type);
+                       b0 = gen_host(cstate, addr, mask, Q_RARP, dir, type);
                        gen_or(b1, b0);
                }
                return b0;
 
        case Q_IP:
-               return gen_hostop(addr, mask, dir, ETHERTYPE_IP, 12, 16);
+               return gen_hostop(cstate, addr, mask, dir, ETHERTYPE_IP, 12, 16);
 
        case Q_RARP:
-               return gen_hostop(addr, mask, dir, ETHERTYPE_REVARP, 14, 24);
+               return gen_hostop(cstate, addr, mask, dir, ETHERTYPE_REVARP, 14, 24);
 
        case Q_ARP:
-               return gen_hostop(addr, mask, dir, ETHERTYPE_ARP, 14, 24);
+               return gen_hostop(cstate, addr, mask, dir, ETHERTYPE_ARP, 14, 24);
 
        case Q_TCP:
-               bpf_error("'tcp' modifier applied to %s", typestr);
+               bpf_error(cstate, "'tcp' modifier applied to %s", typestr);
 
        case Q_SCTP:
-               bpf_error("'sctp' modifier applied to %s", typestr);
+               bpf_error(cstate, "'sctp' modifier applied to %s", typestr);
 
        case Q_UDP:
-               bpf_error("'udp' modifier applied to %s", typestr);
+               bpf_error(cstate, "'udp' modifier applied to %s", typestr);
 
        case Q_ICMP:
-               bpf_error("'icmp' modifier applied to %s", typestr);
+               bpf_error(cstate, "'icmp' modifier applied to %s", typestr);
 
        case Q_IGMP:
-               bpf_error("'igmp' modifier applied to %s", typestr);
+               bpf_error(cstate, "'igmp' modifier applied to %s", typestr);
 
        case Q_IGRP:
-               bpf_error("'igrp' modifier applied to %s", typestr);
+               bpf_error(cstate, "'igrp' modifier applied to %s", typestr);
 
        case Q_PIM:
-               bpf_error("'pim' modifier applied to %s", typestr);
+               bpf_error(cstate, "'pim' modifier applied to %s", typestr);
 
        case Q_VRRP:
-               bpf_error("'vrrp' modifier applied to %s", typestr);
+               bpf_error(cstate, "'vrrp' modifier applied to %s", typestr);
 
        case Q_CARP:
-               bpf_error("'carp' modifier applied to %s", typestr);
+               bpf_error(cstate, "'carp' modifier applied to %s", typestr);
 
        case Q_ATALK:
-               bpf_error("ATALK host filtering not implemented");
+               bpf_error(cstate, "ATALK host filtering not implemented");
 
        case Q_AARP:
-               bpf_error("AARP host filtering not implemented");
+               bpf_error(cstate, "AARP host filtering not implemented");
 
        case Q_DECNET:
-               return gen_dnhostop(addr, dir);
+               return gen_dnhostop(cstate, addr, dir);
 
        case Q_SCA:
-               bpf_error("SCA host filtering not implemented");
+               bpf_error(cstate, "SCA host filtering not implemented");
 
        case Q_LAT:
-               bpf_error("LAT host filtering not implemented");
+               bpf_error(cstate, "LAT host filtering not implemented");
 
        case Q_MOPDL:
-               bpf_error("MOPDL host filtering not implemented");
+               bpf_error(cstate, "MOPDL host filtering not implemented");
 
        case Q_MOPRC:
-               bpf_error("MOPRC host filtering not implemented");
+               bpf_error(cstate, "MOPRC host filtering not implemented");
 
        case Q_IPV6:
-               bpf_error("'ip6' modifier applied to ip host");
+               bpf_error(cstate, "'ip6' modifier applied to ip host");
 
        case Q_ICMPV6:
-               bpf_error("'icmp6' modifier applied to %s", typestr);
+               bpf_error(cstate, "'icmp6' modifier applied to %s", typestr);
 
        case Q_AH:
-               bpf_error("'ah' modifier applied to %s", typestr);
+               bpf_error(cstate, "'ah' modifier applied to %s", typestr);
 
        case Q_ESP:
-               bpf_error("'esp' modifier applied to %s", typestr);
+               bpf_error(cstate, "'esp' modifier applied to %s", typestr);
 
        case Q_ISO:
-               bpf_error("ISO host filtering not implemented");
+               bpf_error(cstate, "ISO host filtering not implemented");
 
        case Q_ESIS:
-               bpf_error("'esis' modifier applied to %s", typestr);
+               bpf_error(cstate, "'esis' modifier applied to %s", typestr);
 
        case Q_ISIS:
-               bpf_error("'isis' modifier applied to %s", typestr);
+               bpf_error(cstate, "'isis' modifier applied to %s", typestr);
 
        case Q_CLNP:
-               bpf_error("'clnp' modifier applied to %s", typestr);
+               bpf_error(cstate, "'clnp' modifier applied to %s", typestr);
 
        case Q_STP:
-               bpf_error("'stp' modifier applied to %s", typestr);
+               bpf_error(cstate, "'stp' modifier applied to %s", typestr);
 
        case Q_IPX:
-               bpf_error("IPX host filtering not implemented");
+               bpf_error(cstate, "IPX host filtering not implemented");
 
        case Q_NETBEUI:
-               bpf_error("'netbeui' modifier applied to %s", typestr);
+               bpf_error(cstate, "'netbeui' modifier applied to %s", typestr);
 
        case Q_RADIO:
-               bpf_error("'radio' modifier applied to %s", typestr);
+               bpf_error(cstate, "'radio' modifier applied to %s", typestr);
 
        default:
                abort();
@@ -4735,12 +4723,8 @@ gen_host(addr, mask, proto, dir, type)
 
 #ifdef INET6
 static struct block *
-gen_host6(addr, mask, proto, dir, type)
-       struct in6_addr *addr;
-       struct in6_addr *mask;
-       int proto;
-       int dir;
-       int type;
+gen_host6(compiler_state_t *cstate, struct in6_addr *addr,
+    struct in6_addr *mask, int proto, int dir, int type)
 {
        const char *typestr;
 
@@ -4752,103 +4736,103 @@ gen_host6(addr, mask, proto, dir, type)
        switch (proto) {
 
        case Q_DEFAULT:
-               return gen_host6(addr, mask, Q_IPV6, dir, type);
+               return gen_host6(cstate, addr, mask, Q_IPV6, dir, type);
 
        case Q_LINK:
-               bpf_error("link-layer modifier applied to ip6 %s", typestr);
+               bpf_error(cstate, "link-layer modifier applied to ip6 %s", typestr);
 
        case Q_IP:
-               bpf_error("'ip' modifier applied to ip6 %s", typestr);
+               bpf_error(cstate, "'ip' modifier applied to ip6 %s", typestr);
 
        case Q_RARP:
-               bpf_error("'rarp' modifier applied to ip6 %s", typestr);
+               bpf_error(cstate, "'rarp' modifier applied to ip6 %s", typestr);
 
        case Q_ARP:
-               bpf_error("'arp' modifier applied to ip6 %s", typestr);
+               bpf_error(cstate, "'arp' modifier applied to ip6 %s", typestr);
 
        case Q_SCTP:
-               bpf_error("'sctp' modifier applied to %s", typestr);
+               bpf_error(cstate, "'sctp' modifier applied to %s", typestr);
 
        case Q_TCP:
-               bpf_error("'tcp' modifier applied to %s", typestr);
+               bpf_error(cstate, "'tcp' modifier applied to %s", typestr);
 
        case Q_UDP:
-               bpf_error("'udp' modifier applied to %s", typestr);
+               bpf_error(cstate, "'udp' modifier applied to %s", typestr);
 
        case Q_ICMP:
-               bpf_error("'icmp' modifier applied to %s", typestr);
+               bpf_error(cstate, "'icmp' modifier applied to %s", typestr);
 
        case Q_IGMP:
-               bpf_error("'igmp' modifier applied to %s", typestr);
+               bpf_error(cstate, "'igmp' modifier applied to %s", typestr);
 
        case Q_IGRP:
-               bpf_error("'igrp' modifier applied to %s", typestr);
+               bpf_error(cstate, "'igrp' modifier applied to %s", typestr);
 
        case Q_PIM:
-               bpf_error("'pim' modifier applied to %s", typestr);
+               bpf_error(cstate, "'pim' modifier applied to %s", typestr);
 
        case Q_VRRP:
-               bpf_error("'vrrp' modifier applied to %s", typestr);
+               bpf_error(cstate, "'vrrp' modifier applied to %s", typestr);
 
        case Q_CARP:
-               bpf_error("'carp' modifier applied to %s", typestr);
+               bpf_error(cstate, "'carp' modifier applied to %s", typestr);
 
        case Q_ATALK:
-               bpf_error("ATALK host filtering not implemented");
+               bpf_error(cstate, "ATALK host filtering not implemented");
 
        case Q_AARP:
-               bpf_error("AARP host filtering not implemented");
+               bpf_error(cstate, "AARP host filtering not implemented");
 
        case Q_DECNET:
-               bpf_error("'decnet' modifier applied to ip6 %s", typestr);
+               bpf_error(cstate, "'decnet' modifier applied to ip6 %s", typestr);
 
        case Q_SCA:
-               bpf_error("SCA host filtering not implemented");
+               bpf_error(cstate, "SCA host filtering not implemented");
 
        case Q_LAT:
-               bpf_error("LAT host filtering not implemented");
+               bpf_error(cstate, "LAT host filtering not implemented");
 
        case Q_MOPDL:
-               bpf_error("MOPDL host filtering not implemented");
+               bpf_error(cstate, "MOPDL host filtering not implemented");
 
        case Q_MOPRC:
-               bpf_error("MOPRC host filtering not implemented");
+               bpf_error(cstate, "MOPRC host filtering not implemented");
 
        case Q_IPV6:
-               return gen_hostop6(addr, mask, dir, ETHERTYPE_IPV6, 8, 24);
+               return gen_hostop6(cstate, addr, mask, dir, ETHERTYPE_IPV6, 8, 24);
 
        case Q_ICMPV6:
-               bpf_error("'icmp6' modifier applied to %s", typestr);
+               bpf_error(cstate, "'icmp6' modifier applied to %s", typestr);
 
        case Q_AH:
-               bpf_error("'ah' modifier applied to %s", typestr);
+               bpf_error(cstate, "'ah' modifier applied to %s", typestr);
 
        case Q_ESP:
-               bpf_error("'esp' modifier applied to %s", typestr);
+               bpf_error(cstate, "'esp' modifier applied to %s", typestr);
 
        case Q_ISO:
-               bpf_error("ISO host filtering not implemented");
+               bpf_error(cstate, "ISO host filtering not implemented");
 
        case Q_ESIS:
-               bpf_error("'esis' modifier applied to %s", typestr);
+               bpf_error(cstate, "'esis' modifier applied to %s", typestr);
 
        case Q_ISIS:
-               bpf_error("'isis' modifier applied to %s", typestr);
+               bpf_error(cstate, "'isis' modifier applied to %s", typestr);
 
        case Q_CLNP:
-               bpf_error("'clnp' modifier applied to %s", typestr);
+               bpf_error(cstate, "'clnp' modifier applied to %s", typestr);
 
        case Q_STP:
-               bpf_error("'stp' modifier applied to %s", typestr);
+               bpf_error(cstate, "'stp' modifier applied to %s", typestr);
 
        case Q_IPX:
-               bpf_error("IPX host filtering not implemented");
+               bpf_error(cstate, "IPX host filtering not implemented");
 
        case Q_NETBEUI:
-               bpf_error("'netbeui' modifier applied to %s", typestr);
+               bpf_error(cstate, "'netbeui' modifier applied to %s", typestr);
 
        case Q_RADIO:
-               bpf_error("'radio' modifier applied to %s", typestr);
+               bpf_error(cstate, "'radio' modifier applied to %s", typestr);
 
        default:
                abort();
@@ -4868,54 +4852,54 @@ gen_gateway(eaddr, alist, proto, dir)
        struct block *b0, *b1, *tmp;
 
        if (dir != 0)
-               bpf_error("direction applied to 'gateway'");
+               bpf_error(cstate, "direction applied to 'gateway'");
 
        switch (proto) {
        case Q_DEFAULT:
        case Q_IP:
        case Q_ARP:
        case Q_RARP:
-               switch (linktype) {
+               switch (cstate->linktype) {
                case DLT_EN10MB:
                case DLT_NETANALYZER:
                case DLT_NETANALYZER_TRANSPARENT:
-                       b1 = gen_prevlinkhdr_check();
-                       b0 = gen_ehostop(eaddr, Q_OR);
+                       b1 = gen_prevlinkhdr_check(cstate);
+                       b0 = gen_ehostop(cstate, eaddr, Q_OR);
                        if (b1 != NULL)
                                gen_and(b1, b0);
                        break;
                case DLT_FDDI:
-                       b0 = gen_fhostop(eaddr, Q_OR);
+                       b0 = gen_fhostop(cstate, eaddr, Q_OR);
                        break;
                case DLT_IEEE802:
-                       b0 = gen_thostop(eaddr, Q_OR);
+                       b0 = gen_thostop(cstate, eaddr, Q_OR);
                        break;
                case DLT_IEEE802_11:
                case DLT_PRISM_HEADER:
                case DLT_IEEE802_11_RADIO_AVS:
                case DLT_IEEE802_11_RADIO:
                case DLT_PPI:
-                       b0 = gen_wlanhostop(eaddr, Q_OR);
+                       b0 = gen_wlanhostop(cstate, eaddr, Q_OR);
                        break;
                case DLT_SUNATM:
                        /*
                         * This is LLC-multiplexed traffic; if it were
-                        * LANE, linktype would have been set to
+                        * LANE, cstate->linktype would have been set to
                         * DLT_EN10MB.
                         */
-                       bpf_error(
+                       bpf_error(cstate,
                            "'gateway' supported only on ethernet/FDDI/token ring/802.11/ATM LANE/Fibre Channel");
                        break;
                case DLT_IP_OVER_FC:
-                       b0 = gen_ipfchostop(eaddr, Q_OR);
+                       b0 = gen_ipfchostop(cstate, eaddr, Q_OR);
                        break;
                default:
-                       bpf_error(
+                       bpf_error(cstate,
                            "'gateway' supported only on ethernet/FDDI/token ring/802.11/ATM LANE/Fibre Channel");
                }
-               b1 = gen_host(**alist++, 0xffffffff, proto, Q_OR, Q_HOST);
+               b1 = gen_host(cstate, **alist++, 0xffffffff, proto, Q_OR, Q_HOST);
                while (*alist) {
-                       tmp = gen_host(**alist++, 0xffffffff, proto, Q_OR,
+                       tmp = gen_host(cstate, **alist++, 0xffffffff, proto, Q_OR,
                            Q_HOST);
                        gen_or(b1, tmp);
                        b1 = tmp;
@@ -4924,14 +4908,13 @@ gen_gateway(eaddr, alist, proto, dir)
                gen_and(b0, b1);
                return b1;
        }
-       bpf_error("illegal modifier of 'gateway'");
+       bpf_error(cstate, "illegal modifier of 'gateway'");
        /* NOTREACHED */
 }
 #endif
 
 struct block *
-gen_proto_abbrev(proto)
-       int proto;
+gen_proto_abbrev(compiler_state_t *cstate, int proto)
 {
        struct block *b0;
        struct block *b1;
@@ -4939,25 +4922,25 @@ gen_proto_abbrev(proto)
        switch (proto) {
 
        case Q_SCTP:
-               b1 = gen_proto(IPPROTO_SCTP, Q_IP, Q_DEFAULT);
-               b0 = gen_proto(IPPROTO_SCTP, Q_IPV6, Q_DEFAULT);
+               b1 = gen_proto(cstate, IPPROTO_SCTP, Q_IP, Q_DEFAULT);
+               b0 = gen_proto(cstate, IPPROTO_SCTP, Q_IPV6, Q_DEFAULT);
                gen_or(b0, b1);
                break;
 
        case Q_TCP:
-               b1 = gen_proto(IPPROTO_TCP, Q_IP, Q_DEFAULT);
-               b0 = gen_proto(IPPROTO_TCP, Q_IPV6, Q_DEFAULT);
+               b1 = gen_proto(cstate, IPPROTO_TCP, Q_IP, Q_DEFAULT);
+               b0 = gen_proto(cstate, IPPROTO_TCP, Q_IPV6, Q_DEFAULT);
                gen_or(b0, b1);
                break;
 
        case Q_UDP:
-               b1 = gen_proto(IPPROTO_UDP, Q_IP, Q_DEFAULT);
-               b0 = gen_proto(IPPROTO_UDP, Q_IPV6, Q_DEFAULT);
+               b1 = gen_proto(cstate, IPPROTO_UDP, Q_IP, Q_DEFAULT);
+               b0 = gen_proto(cstate, IPPROTO_UDP, Q_IPV6, Q_DEFAULT);
                gen_or(b0, b1);
                break;
 
        case Q_ICMP:
-               b1 = gen_proto(IPPROTO_ICMP, Q_IP, Q_DEFAULT);
+               b1 = gen_proto(cstate, IPPROTO_ICMP, Q_IP, Q_DEFAULT);
                break;
 
 #ifndef        IPPROTO_IGMP
@@ -4965,14 +4948,14 @@ gen_proto_abbrev(proto)
 #endif
 
        case Q_IGMP:
-               b1 = gen_proto(IPPROTO_IGMP, Q_IP, Q_DEFAULT);
+               b1 = gen_proto(cstate, IPPROTO_IGMP, Q_IP, Q_DEFAULT);
                break;
 
 #ifndef        IPPROTO_IGRP
 #define        IPPROTO_IGRP    9
 #endif
        case Q_IGRP:
-               b1 = gen_proto(IPPROTO_IGRP, Q_IP, Q_DEFAULT);
+               b1 = gen_proto(cstate, IPPROTO_IGRP, Q_IP, Q_DEFAULT);
                break;
 
 #ifndef IPPROTO_PIM
@@ -4980,8 +4963,8 @@ gen_proto_abbrev(proto)
 #endif
 
        case Q_PIM:
-               b1 = gen_proto(IPPROTO_PIM, Q_IP, Q_DEFAULT);
-               b0 = gen_proto(IPPROTO_PIM, Q_IPV6, Q_DEFAULT);
+               b1 = gen_proto(cstate, IPPROTO_PIM, Q_IP, Q_DEFAULT);
+               b0 = gen_proto(cstate, IPPROTO_PIM, Q_IPV6, Q_DEFAULT);
                gen_or(b0, b1);
                break;
 
@@ -4990,7 +4973,7 @@ gen_proto_abbrev(proto)
 #endif
 
        case Q_VRRP:
-               b1 = gen_proto(IPPROTO_VRRP, Q_IP, Q_DEFAULT);
+               b1 = gen_proto(cstate, IPPROTO_VRRP, Q_IP, Q_DEFAULT);
                break;
 
 #ifndef IPPROTO_CARP
@@ -4998,69 +4981,69 @@ gen_proto_abbrev(proto)
 #endif
 
        case Q_CARP:
-               b1 = gen_proto(IPPROTO_CARP, Q_IP, Q_DEFAULT);
+               b1 = gen_proto(cstate, IPPROTO_CARP, Q_IP, Q_DEFAULT);
                break;
 
        case Q_IP:
-               b1 =  gen_linktype(ETHERTYPE_IP);
+               b1 = gen_linktype(cstate, ETHERTYPE_IP);
                break;
 
        case Q_ARP:
-               b1 =  gen_linktype(ETHERTYPE_ARP);
+               b1 = gen_linktype(cstate, ETHERTYPE_ARP);
                break;
 
        case Q_RARP:
-               b1 =  gen_linktype(ETHERTYPE_REVARP);
+               b1 = gen_linktype(cstate, ETHERTYPE_REVARP);
                break;
 
        case Q_LINK:
-               bpf_error("link layer applied in wrong context");
+               bpf_error(cstate, "link layer applied in wrong context");
 
        case Q_ATALK:
-               b1 =  gen_linktype(ETHERTYPE_ATALK);
+               b1 = gen_linktype(cstate, ETHERTYPE_ATALK);
                break;
 
        case Q_AARP:
-               b1 =  gen_linktype(ETHERTYPE_AARP);
+               b1 = gen_linktype(cstate, ETHERTYPE_AARP);
                break;
 
        case Q_DECNET:
-               b1 =  gen_linktype(ETHERTYPE_DN);
+               b1 = gen_linktype(cstate, ETHERTYPE_DN);
                break;
 
        case Q_SCA:
-               b1 =  gen_linktype(ETHERTYPE_SCA);
+               b1 = gen_linktype(cstate, ETHERTYPE_SCA);
                break;
 
        case Q_LAT:
-               b1 =  gen_linktype(ETHERTYPE_LAT);
+               b1 = gen_linktype(cstate, ETHERTYPE_LAT);
                break;
 
        case Q_MOPDL:
-               b1 =  gen_linktype(ETHERTYPE_MOPDL);
+               b1 = gen_linktype(cstate, ETHERTYPE_MOPDL);
                break;
 
        case Q_MOPRC:
-               b1 =  gen_linktype(ETHERTYPE_MOPRC);
+               b1 = gen_linktype(cstate, ETHERTYPE_MOPRC);
                break;
 
        case Q_IPV6:
-               b1 = gen_linktype(ETHERTYPE_IPV6);
+               b1 = gen_linktype(cstate, ETHERTYPE_IPV6);
                break;
 
 #ifndef IPPROTO_ICMPV6
 #define IPPROTO_ICMPV6 58
 #endif
        case Q_ICMPV6:
-               b1 = gen_proto(IPPROTO_ICMPV6, Q_IPV6, Q_DEFAULT);
+               b1 = gen_proto(cstate, IPPROTO_ICMPV6, Q_IPV6, Q_DEFAULT);
                break;
 
 #ifndef IPPROTO_AH
 #define IPPROTO_AH     51
 #endif
        case Q_AH:
-               b1 = gen_proto(IPPROTO_AH, Q_IP, Q_DEFAULT);
-               b0 = gen_proto(IPPROTO_AH, Q_IPV6, Q_DEFAULT);
+               b1 = gen_proto(cstate, IPPROTO_AH, Q_IP, Q_DEFAULT);
+               b0 = gen_proto(cstate, IPPROTO_AH, Q_IPV6, Q_DEFAULT);
                gen_or(b0, b1);
                break;
 
@@ -5068,101 +5051,101 @@ gen_proto_abbrev(proto)
 #define IPPROTO_ESP    50
 #endif
        case Q_ESP:
-               b1 = gen_proto(IPPROTO_ESP, Q_IP, Q_DEFAULT);
-               b0 = gen_proto(IPPROTO_ESP, Q_IPV6, Q_DEFAULT);
+               b1 = gen_proto(cstate, IPPROTO_ESP, Q_IP, Q_DEFAULT);
+               b0 = gen_proto(cstate, IPPROTO_ESP, Q_IPV6, Q_DEFAULT);
                gen_or(b0, b1);
                break;
 
        case Q_ISO:
-               b1 = gen_linktype(LLCSAP_ISONS);
+               b1 = gen_linktype(cstate, LLCSAP_ISONS);
                break;
 
        case Q_ESIS:
-               b1 = gen_proto(ISO9542_ESIS, Q_ISO, Q_DEFAULT);
+               b1 = gen_proto(cstate, ISO9542_ESIS, Q_ISO, Q_DEFAULT);
                break;
 
        case Q_ISIS:
-               b1 = gen_proto(ISO10589_ISIS, Q_ISO, Q_DEFAULT);
+               b1 = gen_proto(cstate, ISO10589_ISIS, Q_ISO, Q_DEFAULT);
                break;
 
        case Q_ISIS_L1: /* all IS-IS Level1 PDU-Types */
-               b0 = gen_proto(ISIS_L1_LAN_IIH, Q_ISIS, Q_DEFAULT);
-               b1 = gen_proto(ISIS_PTP_IIH, Q_ISIS, Q_DEFAULT); /* FIXME extract the circuit-type bits */
+               b0 = gen_proto(cstate, ISIS_L1_LAN_IIH, Q_ISIS, Q_DEFAULT);
+               b1 = gen_proto(cstate, ISIS_PTP_IIH, Q_ISIS, Q_DEFAULT); /* FIXME extract the circuit-type bits */
                gen_or(b0, b1);
-               b0 = gen_proto(ISIS_L1_LSP, Q_ISIS, Q_DEFAULT);
+               b0 = gen_proto(cstate, ISIS_L1_LSP, Q_ISIS, Q_DEFAULT);
                gen_or(b0, b1);
-               b0 = gen_proto(ISIS_L1_CSNP, Q_ISIS, Q_DEFAULT);
+               b0 = gen_proto(cstate, ISIS_L1_CSNP, Q_ISIS, Q_DEFAULT);
                gen_or(b0, b1);
-               b0 = gen_proto(ISIS_L1_PSNP, Q_ISIS, Q_DEFAULT);
+               b0 = gen_proto(cstate, ISIS_L1_PSNP, Q_ISIS, Q_DEFAULT);
                gen_or(b0, b1);
                break;
 
        case Q_ISIS_L2: /* all IS-IS Level2 PDU-Types */
-               b0 = gen_proto(ISIS_L2_LAN_IIH, Q_ISIS, Q_DEFAULT);
-               b1 = gen_proto(ISIS_PTP_IIH, Q_ISIS, Q_DEFAULT); /* FIXME extract the circuit-type bits */
+               b0 = gen_proto(cstate, ISIS_L2_LAN_IIH, Q_ISIS, Q_DEFAULT);
+               b1 = gen_proto(cstate, ISIS_PTP_IIH, Q_ISIS, Q_DEFAULT); /* FIXME extract the circuit-type bits */
                gen_or(b0, b1);
-               b0 = gen_proto(ISIS_L2_LSP, Q_ISIS, Q_DEFAULT);
+               b0 = gen_proto(cstate, ISIS_L2_LSP, Q_ISIS, Q_DEFAULT);
                gen_or(b0, b1);
-               b0 = gen_proto(ISIS_L2_CSNP, Q_ISIS, Q_DEFAULT);
+               b0 = gen_proto(cstate, ISIS_L2_CSNP, Q_ISIS, Q_DEFAULT);
                gen_or(b0, b1);
-               b0 = gen_proto(ISIS_L2_PSNP, Q_ISIS, Q_DEFAULT);
+               b0 = gen_proto(cstate, ISIS_L2_PSNP, Q_ISIS, Q_DEFAULT);
                gen_or(b0, b1);
                break;
 
        case Q_ISIS_IIH: /* all IS-IS Hello PDU-Types */
-               b0 = gen_proto(ISIS_L1_LAN_IIH, Q_ISIS, Q_DEFAULT);
-               b1 = gen_proto(ISIS_L2_LAN_IIH, Q_ISIS, Q_DEFAULT);
+               b0 = gen_proto(cstate, ISIS_L1_LAN_IIH, Q_ISIS, Q_DEFAULT);
+               b1 = gen_proto(cstate, ISIS_L2_LAN_IIH, Q_ISIS, Q_DEFAULT);
                gen_or(b0, b1);
-               b0 = gen_proto(ISIS_PTP_IIH, Q_ISIS, Q_DEFAULT);
+               b0 = gen_proto(cstate, ISIS_PTP_IIH, Q_ISIS, Q_DEFAULT);
                gen_or(b0, b1);
                break;
 
        case Q_ISIS_LSP:
-               b0 = gen_proto(ISIS_L1_LSP, Q_ISIS, Q_DEFAULT);
-               b1 = gen_proto(ISIS_L2_LSP, Q_ISIS, Q_DEFAULT);
+               b0 = gen_proto(cstate, ISIS_L1_LSP, Q_ISIS, Q_DEFAULT);
+               b1 = gen_proto(cstate, ISIS_L2_LSP, Q_ISIS, Q_DEFAULT);
                gen_or(b0, b1);
                break;
 
        case Q_ISIS_SNP:
-               b0 = gen_proto(ISIS_L1_CSNP, Q_ISIS, Q_DEFAULT);
-               b1 = gen_proto(ISIS_L2_CSNP, Q_ISIS, Q_DEFAULT);
+               b0 = gen_proto(cstate, ISIS_L1_CSNP, Q_ISIS, Q_DEFAULT);
+               b1 = gen_proto(cstate, ISIS_L2_CSNP, Q_ISIS, Q_DEFAULT);
                gen_or(b0, b1);
-               b0 = gen_proto(ISIS_L1_PSNP, Q_ISIS, Q_DEFAULT);
+               b0 = gen_proto(cstate, ISIS_L1_PSNP, Q_ISIS, Q_DEFAULT);
                gen_or(b0, b1);
-               b0 = gen_proto(ISIS_L2_PSNP, Q_ISIS, Q_DEFAULT);
+               b0 = gen_proto(cstate, ISIS_L2_PSNP, Q_ISIS, Q_DEFAULT);
                gen_or(b0, b1);
                break;
 
        case Q_ISIS_CSNP:
-               b0 = gen_proto(ISIS_L1_CSNP, Q_ISIS, Q_DEFAULT);
-               b1 = gen_proto(ISIS_L2_CSNP, Q_ISIS, Q_DEFAULT);
+               b0 = gen_proto(cstate, ISIS_L1_CSNP, Q_ISIS, Q_DEFAULT);
+               b1 = gen_proto(cstate, ISIS_L2_CSNP, Q_ISIS, Q_DEFAULT);
                gen_or(b0, b1);
                break;
 
        case Q_ISIS_PSNP:
-               b0 = gen_proto(ISIS_L1_PSNP, Q_ISIS, Q_DEFAULT);
-               b1 = gen_proto(ISIS_L2_PSNP, Q_ISIS, Q_DEFAULT);
+               b0 = gen_proto(cstate, ISIS_L1_PSNP, Q_ISIS, Q_DEFAULT);
+               b1 = gen_proto(cstate, ISIS_L2_PSNP, Q_ISIS, Q_DEFAULT);
                gen_or(b0, b1);
                break;
 
        case Q_CLNP:
-               b1 = gen_proto(ISO8473_CLNP, Q_ISO, Q_DEFAULT);
+               b1 = gen_proto(cstate, ISO8473_CLNP, Q_ISO, Q_DEFAULT);
                break;
 
        case Q_STP:
-               b1 = gen_linktype(LLCSAP_8021D);
+               b1 = gen_linktype(cstate, LLCSAP_8021D);
                break;
 
        case Q_IPX:
-               b1 = gen_linktype(LLCSAP_IPX);
+               b1 = gen_linktype(cstate, LLCSAP_IPX);
                break;
 
        case Q_NETBEUI:
-               b1 = gen_linktype(LLCSAP_NETBEUI);
+               b1 = gen_linktype(cstate, LLCSAP_NETBEUI);
                break;
 
        case Q_RADIO:
-               bpf_error("'radio' is not a valid protocol type");
+               bpf_error(cstate, "'radio' is not a valid protocol type");
 
        default:
                abort();
@@ -5171,14 +5154,14 @@ gen_proto_abbrev(proto)
 }
 
 static struct block *
-gen_ipfrag()
+gen_ipfrag(compiler_state_t *cstate)
 {
        struct slist *s;
        struct block *b;
 
        /* not IPv4 frag other than the first frag */
-       s = gen_load_a(OR_LINKPL, 6, BPF_H);
-       b = new_block(JMP(BPF_JSET));
+       s = gen_load_a(cstate, OR_LINKPL, 6, BPF_H);
+       b = new_block(cstate, JMP(BPF_JSET));
        b->s.k = 0x1fff;
        b->stmts = s;
        gen_not(b);
@@ -5196,51 +5179,46 @@ gen_ipfrag()
  * headers).
  */
 static struct block *
-gen_portatom(off, v)
-       int off;
-       bpf_int32 v;
+gen_portatom(compiler_state_t *cstate, int off, bpf_int32 v)
 {
-       return gen_cmp(OR_TRAN_IPV4, off, BPF_H, v);
+       return gen_cmp(cstate, OR_TRAN_IPV4, off, BPF_H, v);
 }
 
 static struct block *
-gen_portatom6(off, v)
-       int off;
-       bpf_int32 v;
+gen_portatom6(compiler_state_t *cstate, int off, bpf_int32 v)
 {
-       return gen_cmp(OR_TRAN_IPV6, off, BPF_H, v);
+       return gen_cmp(cstate, OR_TRAN_IPV6, off, BPF_H, v);
 }
 
 struct block *
-gen_portop(port, proto, dir)
-       int port, proto, dir;
+gen_portop(compiler_state_t *cstate, int port, int proto, int dir)
 {
        struct block *b0, *b1, *tmp;
 
        /* ip proto 'proto' and not a fragment other than the first fragment */
-       tmp = gen_cmp(OR_LINKPL, 9, BPF_B, (bpf_int32)proto);
-       b0 = gen_ipfrag();
+       tmp = gen_cmp(cstate, OR_LINKPL, 9, BPF_B, (bpf_int32)proto);
+       b0 = gen_ipfrag(cstate);
        gen_and(tmp, b0);
 
        switch (dir) {
        case Q_SRC:
-               b1 = gen_portatom(0, (bpf_int32)port);
+               b1 = gen_portatom(cstate, 0, (bpf_int32)port);
                break;
 
        case Q_DST:
-               b1 = gen_portatom(2, (bpf_int32)port);
+               b1 = gen_portatom(cstate, 2, (bpf_int32)port);
                break;
 
        case Q_OR:
        case Q_DEFAULT:
-               tmp = gen_portatom(0, (bpf_int32)port);
-               b1 = gen_portatom(2, (bpf_int32)port);
+               tmp = gen_portatom(cstate, 0, (bpf_int32)port);
+               b1 = gen_portatom(cstate, 2, (bpf_int32)port);
                gen_or(tmp, b1);
                break;
 
        case Q_AND:
-               tmp = gen_portatom(0, (bpf_int32)port);
-               b1 = gen_portatom(2, (bpf_int32)port);
+               tmp = gen_portatom(cstate, 0, (bpf_int32)port);
+               b1 = gen_portatom(cstate, 2, (bpf_int32)port);
                gen_and(tmp, b1);
                break;
 
@@ -5253,10 +5231,7 @@ gen_portop(port, proto, dir)
 }
 
 static struct block *
-gen_port(port, ip_proto, dir)
-       int port;
-       int ip_proto;
-       int dir;
+gen_port(compiler_state_t *cstate, int port, int ip_proto, int dir)
 {
        struct block *b0, *b1, *tmp;
 
@@ -5277,20 +5252,20 @@ gen_port(port, ip_proto, dir)
         *
         * So we always check for ETHERTYPE_IP.
         */
-       b0 =  gen_linktype(ETHERTYPE_IP);
+       b0 = gen_linktype(cstate, ETHERTYPE_IP);
 
        switch (ip_proto) {
        case IPPROTO_UDP:
        case IPPROTO_TCP:
        case IPPROTO_SCTP:
-               b1 = gen_portop(port, ip_proto, dir);
+               b1 = gen_portop(cstate, port, ip_proto, dir);
                break;
 
        case PROTO_UNDEF:
-               tmp = gen_portop(port, IPPROTO_TCP, dir);
-               b1 = gen_portop(port, IPPROTO_UDP, dir);
+               tmp = gen_portop(cstate, port, IPPROTO_TCP, dir);
+               b1 = gen_portop(cstate, port, IPPROTO_UDP, dir);
                gen_or(tmp, b1);
-               tmp = gen_portop(port, IPPROTO_SCTP, dir);
+               tmp = gen_portop(cstate, port, IPPROTO_SCTP, dir);
                gen_or(tmp, b1);
                break;
 
@@ -5302,34 +5277,33 @@ gen_port(port, ip_proto, dir)
 }
 
 struct block *
-gen_portop6(port, proto, dir)
-       int port, proto, dir;
+gen_portop6(compiler_state_t *cstate, int port, int proto, int dir)
 {
        struct block *b0, *b1, *tmp;
 
        /* ip6 proto 'proto' */
        /* XXX - catch the first fragment of a fragmented packet? */
-       b0 = gen_cmp(OR_LINKPL, 6, BPF_B, (bpf_int32)proto);
+       b0 = gen_cmp(cstate, OR_LINKPL, 6, BPF_B, (bpf_int32)proto);
 
        switch (dir) {
        case Q_SRC:
-               b1 = gen_portatom6(0, (bpf_int32)port);
+               b1 = gen_portatom6(cstate, 0, (bpf_int32)port);
                break;
 
        case Q_DST:
-               b1 = gen_portatom6(2, (bpf_int32)port);
+               b1 = gen_portatom6(cstate, 2, (bpf_int32)port);
                break;
 
        case Q_OR:
        case Q_DEFAULT:
-               tmp = gen_portatom6(0, (bpf_int32)port);
-               b1 = gen_portatom6(2, (bpf_int32)port);
+               tmp = gen_portatom6(cstate, 0, (bpf_int32)port);
+               b1 = gen_portatom6(cstate, 2, (bpf_int32)port);
                gen_or(tmp, b1);
                break;
 
        case Q_AND:
-               tmp = gen_portatom6(0, (bpf_int32)port);
-               b1 = gen_portatom6(2, (bpf_int32)port);
+               tmp = gen_portatom6(cstate, 0, (bpf_int32)port);
+               b1 = gen_portatom6(cstate, 2, (bpf_int32)port);
                gen_and(tmp, b1);
                break;
 
@@ -5342,28 +5316,25 @@ gen_portop6(port, proto, dir)
 }
 
 static struct block *
-gen_port6(port, ip_proto, dir)
-       int port;
-       int ip_proto;
-       int dir;
+gen_port6(compiler_state_t *cstate, int port, int ip_proto, int dir)
 {
        struct block *b0, *b1, *tmp;
 
        /* link proto ip6 */
-       b0 =  gen_linktype(ETHERTYPE_IPV6);
+       b0 = gen_linktype(cstate, ETHERTYPE_IPV6);
 
        switch (ip_proto) {
        case IPPROTO_UDP:
        case IPPROTO_TCP:
        case IPPROTO_SCTP:
-               b1 = gen_portop6(port, ip_proto, dir);
+               b1 = gen_portop6(cstate, port, ip_proto, dir);
                break;
 
        case PROTO_UNDEF:
-               tmp = gen_portop6(port, IPPROTO_TCP, dir);
-               b1 = gen_portop6(port, IPPROTO_UDP, dir);
+               tmp = gen_portop6(cstate, port, IPPROTO_TCP, dir);
+               b1 = gen_portop6(cstate, port, IPPROTO_UDP, dir);
                gen_or(tmp, b1);
-               tmp = gen_portop6(port, IPPROTO_SCTP, dir);
+               tmp = gen_portop6(cstate, port, IPPROTO_SCTP, dir);
                gen_or(tmp, b1);
                break;
 
@@ -5376,9 +5347,8 @@ gen_port6(port, ip_proto, dir)
 
 /* gen_portrange code */
 static struct block *
-gen_portrangeatom(off, v1, v2)
-       int off;
-       bpf_int32 v1, v2;
+gen_portrangeatom(compiler_state_t *cstate, int off, bpf_int32 v1,
+    bpf_int32 v2)
 {
        struct block *b1, *b2;
 
@@ -5393,8 +5363,8 @@ gen_portrangeatom(off, v1, v2)
                v2 = vtemp;
        }
 
-       b1 = gen_cmp_ge(OR_TRAN_IPV4, off, BPF_H, v1);
-       b2 = gen_cmp_le(OR_TRAN_IPV4, off, BPF_H, v2);
+       b1 = gen_cmp_ge(cstate, OR_TRAN_IPV4, off, BPF_H, v1);
+       b2 = gen_cmp_le(cstate, OR_TRAN_IPV4, off, BPF_H, v2);
 
        gen_and(b1, b2);
 
@@ -5402,37 +5372,35 @@ gen_portrangeatom(off, v1, v2)
 }
 
 struct block *
-gen_portrangeop(port1, port2, proto, dir)
-       int port1, port2;
-       int proto;
-       int dir;
+gen_portrangeop(compiler_state_t *cstate, int port1, int port2, int proto,
+    int dir)
 {
        struct block *b0, *b1, *tmp;
 
        /* ip proto 'proto' and not a fragment other than the first fragment */
-       tmp = gen_cmp(OR_LINKPL, 9, BPF_B, (bpf_int32)proto);
-       b0 = gen_ipfrag();
+       tmp = gen_cmp(cstate, OR_LINKPL, 9, BPF_B, (bpf_int32)proto);
+       b0 = gen_ipfrag(cstate);
        gen_and(tmp, b0);
 
        switch (dir) {
        case Q_SRC:
-               b1 = gen_portrangeatom(0, (bpf_int32)port1, (bpf_int32)port2);
+               b1 = gen_portrangeatom(cstate, 0, (bpf_int32)port1, (bpf_int32)port2);
                break;
 
        case Q_DST:
-               b1 = gen_portrangeatom(2, (bpf_int32)port1, (bpf_int32)port2);
+               b1 = gen_portrangeatom(cstate, 2, (bpf_int32)port1, (bpf_int32)port2);
                break;
 
        case Q_OR:
        case Q_DEFAULT:
-               tmp = gen_portrangeatom(0, (bpf_int32)port1, (bpf_int32)port2);
-               b1 = gen_portrangeatom(2, (bpf_int32)port1, (bpf_int32)port2);
+               tmp = gen_portrangeatom(cstate, 0, (bpf_int32)port1, (bpf_int32)port2);
+               b1 = gen_portrangeatom(cstate, 2, (bpf_int32)port1, (bpf_int32)port2);
                gen_or(tmp, b1);
                break;
 
        case Q_AND:
-               tmp = gen_portrangeatom(0, (bpf_int32)port1, (bpf_int32)port2);
-               b1 = gen_portrangeatom(2, (bpf_int32)port1, (bpf_int32)port2);
+               tmp = gen_portrangeatom(cstate, 0, (bpf_int32)port1, (bpf_int32)port2);
+               b1 = gen_portrangeatom(cstate, 2, (bpf_int32)port1, (bpf_int32)port2);
                gen_and(tmp, b1);
                break;
 
@@ -5445,28 +5413,26 @@ gen_portrangeop(port1, port2, proto, dir)
 }
 
 static struct block *
-gen_portrange(port1, port2, ip_proto, dir)
-       int port1, port2;
-       int ip_proto;
-       int dir;
+gen_portrange(compiler_state_t *cstate, int port1, int port2, int ip_proto,
+    int dir)
 {
        struct block *b0, *b1, *tmp;
 
        /* link proto ip */
-       b0 =  gen_linktype(ETHERTYPE_IP);
+       b0 = gen_linktype(cstate, ETHERTYPE_IP);
 
        switch (ip_proto) {
        case IPPROTO_UDP:
        case IPPROTO_TCP:
        case IPPROTO_SCTP:
-               b1 = gen_portrangeop(port1, port2, ip_proto, dir);
+               b1 = gen_portrangeop(cstate, port1, port2, ip_proto, dir);
                break;
 
        case PROTO_UNDEF:
-               tmp = gen_portrangeop(port1, port2, IPPROTO_TCP, dir);
-               b1 = gen_portrangeop(port1, port2, IPPROTO_UDP, dir);
+               tmp = gen_portrangeop(cstate, port1, port2, IPPROTO_TCP, dir);
+               b1 = gen_portrangeop(cstate, port1, port2, IPPROTO_UDP, dir);
                gen_or(tmp, b1);
-               tmp = gen_portrangeop(port1, port2, IPPROTO_SCTP, dir);
+               tmp = gen_portrangeop(cstate, port1, port2, IPPROTO_SCTP, dir);
                gen_or(tmp, b1);
                break;
 
@@ -5478,9 +5444,8 @@ gen_portrange(port1, port2, ip_proto, dir)
 }
 
 static struct block *
-gen_portrangeatom6(off, v1, v2)
-       int off;
-       bpf_int32 v1, v2;
+gen_portrangeatom6(compiler_state_t *cstate, int off, bpf_int32 v1,
+    bpf_int32 v2)
 {
        struct block *b1, *b2;
 
@@ -5495,8 +5460,8 @@ gen_portrangeatom6(off, v1, v2)
                v2 = vtemp;
        }
 
-       b1 = gen_cmp_ge(OR_TRAN_IPV6, off, BPF_H, v1);
-       b2 = gen_cmp_le(OR_TRAN_IPV6, off, BPF_H, v2);
+       b1 = gen_cmp_ge(cstate, OR_TRAN_IPV6, off, BPF_H, v1);
+       b2 = gen_cmp_le(cstate, OR_TRAN_IPV6, off, BPF_H, v2);
 
        gen_and(b1, b2);
 
@@ -5504,36 +5469,34 @@ gen_portrangeatom6(off, v1, v2)
 }
 
 struct block *
-gen_portrangeop6(port1, port2, proto, dir)
-       int port1, port2;
-       int proto;
-       int dir;
+gen_portrangeop6(compiler_state_t *cstate, int port1, int port2, int proto,
+    int dir)
 {
        struct block *b0, *b1, *tmp;
 
        /* ip6 proto 'proto' */
        /* XXX - catch the first fragment of a fragmented packet? */
-       b0 = gen_cmp(OR_LINKPL, 6, BPF_B, (bpf_int32)proto);
+       b0 = gen_cmp(cstate, OR_LINKPL, 6, BPF_B, (bpf_int32)proto);
 
        switch (dir) {
        case Q_SRC:
-               b1 = gen_portrangeatom6(0, (bpf_int32)port1, (bpf_int32)port2);
+               b1 = gen_portrangeatom6(cstate, 0, (bpf_int32)port1, (bpf_int32)port2);
                break;
 
        case Q_DST:
-               b1 = gen_portrangeatom6(2, (bpf_int32)port1, (bpf_int32)port2);
+               b1 = gen_portrangeatom6(cstate, 2, (bpf_int32)port1, (bpf_int32)port2);
                break;
 
        case Q_OR:
        case Q_DEFAULT:
-               tmp = gen_portrangeatom6(0, (bpf_int32)port1, (bpf_int32)port2);
-               b1 = gen_portrangeatom6(2, (bpf_int32)port1, (bpf_int32)port2);
+               tmp = gen_portrangeatom6(cstate, 0, (bpf_int32)port1, (bpf_int32)port2);
+               b1 = gen_portrangeatom6(cstate, 2, (bpf_int32)port1, (bpf_int32)port2);
                gen_or(tmp, b1);
                break;
 
        case Q_AND:
-               tmp = gen_portrangeatom6(0, (bpf_int32)port1, (bpf_int32)port2);
-               b1 = gen_portrangeatom6(2, (bpf_int32)port1, (bpf_int32)port2);
+               tmp = gen_portrangeatom6(cstate, 0, (bpf_int32)port1, (bpf_int32)port2);
+               b1 = gen_portrangeatom6(cstate, 2, (bpf_int32)port1, (bpf_int32)port2);
                gen_and(tmp, b1);
                break;
 
@@ -5546,28 +5509,26 @@ gen_portrangeop6(port1, port2, proto, dir)
 }
 
 static struct block *
-gen_portrange6(port1, port2, ip_proto, dir)
-       int port1, port2;
-       int ip_proto;
-       int dir;
+gen_portrange6(compiler_state_t *cstate, int port1, int port2, int ip_proto,
+    int dir)
 {
        struct block *b0, *b1, *tmp;
 
        /* link proto ip6 */
-       b0 =  gen_linktype(ETHERTYPE_IPV6);
+       b0 = gen_linktype(cstate, ETHERTYPE_IPV6);
 
        switch (ip_proto) {
        case IPPROTO_UDP:
        case IPPROTO_TCP:
        case IPPROTO_SCTP:
-               b1 = gen_portrangeop6(port1, port2, ip_proto, dir);
+               b1 = gen_portrangeop6(cstate, port1, port2, ip_proto, dir);
                break;
 
        case PROTO_UNDEF:
-               tmp = gen_portrangeop6(port1, port2, IPPROTO_TCP, dir);
-               b1 = gen_portrangeop6(port1, port2, IPPROTO_UDP, dir);
+               tmp = gen_portrangeop6(cstate, port1, port2, IPPROTO_TCP, dir);
+               b1 = gen_portrangeop6(cstate, port1, port2, IPPROTO_UDP, dir);
                gen_or(tmp, b1);
-               tmp = gen_portrangeop6(port1, port2, IPPROTO_SCTP, dir);
+               tmp = gen_portrangeop6(cstate, port1, port2, IPPROTO_SCTP, dir);
                gen_or(tmp, b1);
                break;
 
@@ -5579,9 +5540,7 @@ gen_portrange6(port1, port2, ip_proto, dir)
 }
 
 static int
-lookup_proto(name, proto)
-       register const char *name;
-       register int proto;
+lookup_proto(compiler_state_t *cstate, const char *name, int proto)
 {
        register int v;
 
@@ -5592,16 +5551,16 @@ lookup_proto(name, proto)
        case Q_IPV6:
                v = pcap_nametoproto(name);
                if (v == PROTO_UNDEF)
-                       bpf_error("unknown ip proto '%s'", name);
+                       bpf_error(cstate, "unknown ip proto '%s'", name);
                break;
 
        case Q_LINK:
-               /* XXX should look up h/w protocol type based on linktype */
+               /* XXX should look up h/w protocol type based on cstate->linktype */
                v = pcap_nametoeproto(name);
                if (v == PROTO_UNDEF) {
                        v = pcap_nametollc(name);
                        if (v == PROTO_UNDEF)
-                               bpf_error("unknown ether proto '%s'", name);
+                               bpf_error(cstate, "unknown ether proto '%s'", name);
                }
                break;
 
@@ -5613,7 +5572,7 @@ lookup_proto(name, proto)
                else if (strcmp(name, "clnp") == 0)
                        v = ISO8473_CLNP;
                else
-                       bpf_error("unknown osi proto '%s'", name);
+                       bpf_error(cstate, "unknown osi proto '%s'", name);
                break;
 
        default:
@@ -5634,20 +5593,17 @@ gen_joinsp(s, n)
 #endif
 
 static struct block *
-gen_protochain(v, proto, dir)
-       int v;
-       int proto;
-       int dir;
+gen_protochain(compiler_state_t *cstate, int v, int proto, int dir)
 {
 #ifdef NO_PROTOCHAIN
-       return gen_proto(v, proto, dir);
+       return gen_proto(cstate, v, proto, dir);
 #else
        struct block *b0, *b;
        struct slist *s[100];
        int fix2, fix3, fix4, fix5;
        int ahcheck, again, end;
        int i, max;
-       int reg2 = alloc_reg();
+       int reg2 = alloc_reg(cstate);
 
        memset(s, 0, sizeof(s));
        fix3 = fix4 = fix5 = 0;
@@ -5657,12 +5613,12 @@ gen_protochain(v, proto, dir)
        case Q_IPV6:
                break;
        case Q_DEFAULT:
-               b0 = gen_protochain(v, Q_IP, dir);
-               b = gen_protochain(v, Q_IPV6, dir);
+               b0 = gen_protochain(cstate, v, Q_IP, dir);
+               b = gen_protochain(cstate, v, Q_IPV6, dir);
                gen_or(b0, b);
                return b;
        default:
-               bpf_error("bad protocol applied for 'protochain'");
+               bpf_error(cstate, "bad protocol applied for 'protochain'");
                /*NOTREACHED*/
        }
 
@@ -5677,10 +5633,10 @@ gen_protochain(v, proto, dir)
         * branches, and backward branch support is unlikely to appear
         * in kernel BPF engines.)
         */
-       if (off_linkpl.is_variable)
-               bpf_error("'protochain' not supported with variable length headers");
+       if (cstate->off_linkpl.is_variable)
+               bpf_error(cstate, "'protochain' not supported with variable length headers");
 
-       no_optimize = 1; /*this code is not compatible with optimzer yet */
+       cstate->no_optimize = 1; /*this code is not compatible with optimzer yet */
 
        /*
         * s[0] is a dummy entry to protect other BPF insn from damage
@@ -5688,44 +5644,44 @@ gen_protochain(v, proto, dir)
         * hard to find interdependency made by jump table fixup.
         */
        i = 0;
-       s[i] = new_stmt(0);     /*dummy*/
+       s[i] = new_stmt(cstate, 0);     /*dummy*/
        i++;
 
        switch (proto) {
        case Q_IP:
-               b0 = gen_linktype(ETHERTYPE_IP);
+               b0 = gen_linktype(cstate, ETHERTYPE_IP);
 
                /* A = ip->ip_p */
-               s[i] = new_stmt(BPF_LD|BPF_ABS|BPF_B);
-               s[i]->s.k = off_linkpl.constant_part + off_nl + 9;
+               s[i] = new_stmt(cstate, BPF_LD|BPF_ABS|BPF_B);
+               s[i]->s.k = cstate->off_linkpl.constant_part + cstate->off_nl + 9;
                i++;
                /* X = ip->ip_hl << 2 */
-               s[i] = new_stmt(BPF_LDX|BPF_MSH|BPF_B);
-               s[i]->s.k = off_linkpl.constant_part + off_nl;
+               s[i] = new_stmt(cstate, BPF_LDX|BPF_MSH|BPF_B);
+               s[i]->s.k = cstate->off_linkpl.constant_part + cstate->off_nl;
                i++;
                break;
 
        case Q_IPV6:
-               b0 = gen_linktype(ETHERTYPE_IPV6);
+               b0 = gen_linktype(cstate, ETHERTYPE_IPV6);
 
                /* A = ip6->ip_nxt */
-               s[i] = new_stmt(BPF_LD|BPF_ABS|BPF_B);
-               s[i]->s.k = off_linkpl.constant_part + off_nl + 6;
+               s[i] = new_stmt(cstate, BPF_LD|BPF_ABS|BPF_B);
+               s[i]->s.k = cstate->off_linkpl.constant_part + cstate->off_nl + 6;
                i++;
                /* X = sizeof(struct ip6_hdr) */
-               s[i] = new_stmt(BPF_LDX|BPF_IMM);
+               s[i] = new_stmt(cstate, BPF_LDX|BPF_IMM);
                s[i]->s.k = 40;
                i++;
                break;
 
        default:
-               bpf_error("unsupported proto to gen_protochain");
+               bpf_error(cstate, "unsupported proto to gen_protochain");
                /*NOTREACHED*/
        }
 
        /* again: if (A == v) goto end; else fall through; */
        again = i;
-       s[i] = new_stmt(BPF_JMP|BPF_JEQ|BPF_K);
+       s[i] = new_stmt(cstate, BPF_JMP|BPF_JEQ|BPF_K);
        s[i]->s.k = v;
        s[i]->s.jt = NULL;              /*later*/
        s[i]->s.jf = NULL;              /*update in next stmt*/
@@ -5736,7 +5692,7 @@ gen_protochain(v, proto, dir)
 #define IPPROTO_NONE   59
 #endif
        /* if (A == IPPROTO_NONE) goto end */
-       s[i] = new_stmt(BPF_JMP|BPF_JEQ|BPF_K);
+       s[i] = new_stmt(cstate, BPF_JMP|BPF_JEQ|BPF_K);
        s[i]->s.jt = NULL;      /*later*/
        s[i]->s.jf = NULL;      /*update in next stmt*/
        s[i]->s.k = IPPROTO_NONE;
@@ -5749,26 +5705,26 @@ gen_protochain(v, proto, dir)
 
                v6start = i;
                /* if (A == IPPROTO_HOPOPTS) goto v6advance */
-               s[i] = new_stmt(BPF_JMP|BPF_JEQ|BPF_K);
+               s[i] = new_stmt(cstate, BPF_JMP|BPF_JEQ|BPF_K);
                s[i]->s.jt = NULL;      /*later*/
                s[i]->s.jf = NULL;      /*update in next stmt*/
                s[i]->s.k = IPPROTO_HOPOPTS;
                s[fix2]->s.jf = s[i];
                i++;
                /* if (A == IPPROTO_DSTOPTS) goto v6advance */
-               s[i - 1]->s.jf = s[i] = new_stmt(BPF_JMP|BPF_JEQ|BPF_K);
+               s[i - 1]->s.jf = s[i] = new_stmt(cstate, BPF_JMP|BPF_JEQ|BPF_K);
                s[i]->s.jt = NULL;      /*later*/
                s[i]->s.jf = NULL;      /*update in next stmt*/
                s[i]->s.k = IPPROTO_DSTOPTS;
                i++;
                /* if (A == IPPROTO_ROUTING) goto v6advance */
-               s[i - 1]->s.jf = s[i] = new_stmt(BPF_JMP|BPF_JEQ|BPF_K);
+               s[i - 1]->s.jf = s[i] = new_stmt(cstate, BPF_JMP|BPF_JEQ|BPF_K);
                s[i]->s.jt = NULL;      /*later*/
                s[i]->s.jf = NULL;      /*update in next stmt*/
                s[i]->s.k = IPPROTO_ROUTING;
                i++;
                /* if (A == IPPROTO_FRAGMENT) goto v6advance; else goto ahcheck; */
-               s[i - 1]->s.jf = s[i] = new_stmt(BPF_JMP|BPF_JEQ|BPF_K);
+               s[i - 1]->s.jf = s[i] = new_stmt(cstate, BPF_JMP|BPF_JEQ|BPF_K);
                s[i]->s.jt = NULL;      /*later*/
                s[i]->s.jf = NULL;      /*later*/
                s[i]->s.k = IPPROTO_FRAGMENT;
@@ -5785,39 +5741,39 @@ gen_protochain(v, proto, dir)
                 * X = X + (P[X + packet head + 1] + 1) * 8;
                 */
                /* A = P[X + packet head] */
-               s[i] = new_stmt(BPF_LD|BPF_IND|BPF_B);
-               s[i]->s.k = off_linkpl.constant_part + off_nl;
+               s[i] = new_stmt(cstate, BPF_LD|BPF_IND|BPF_B);
+               s[i]->s.k = cstate->off_linkpl.constant_part + cstate->off_nl;
                i++;
                /* MEM[reg2] = A */
-               s[i] = new_stmt(BPF_ST);
+               s[i] = new_stmt(cstate, BPF_ST);
                s[i]->s.k = reg2;
                i++;
                /* A = P[X + packet head + 1]; */
-               s[i] = new_stmt(BPF_LD|BPF_IND|BPF_B);
-               s[i]->s.k = off_linkpl.constant_part + off_nl + 1;
+               s[i] = new_stmt(cstate, BPF_LD|BPF_IND|BPF_B);
+               s[i]->s.k = cstate->off_linkpl.constant_part + cstate->off_nl + 1;
                i++;
                /* A += 1 */
-               s[i] = new_stmt(BPF_ALU|BPF_ADD|BPF_K);
+               s[i] = new_stmt(cstate, BPF_ALU|BPF_ADD|BPF_K);
                s[i]->s.k = 1;
                i++;
                /* A *= 8 */
-               s[i] = new_stmt(BPF_ALU|BPF_MUL|BPF_K);
+               s[i] = new_stmt(cstate, BPF_ALU|BPF_MUL|BPF_K);
                s[i]->s.k = 8;
                i++;
                /* A += X */
-               s[i] = new_stmt(BPF_ALU|BPF_ADD|BPF_X);
+               s[i] = new_stmt(cstate, BPF_ALU|BPF_ADD|BPF_X);
                s[i]->s.k = 0;
                i++;
                /* X = A; */
-               s[i] = new_stmt(BPF_MISC|BPF_TAX);
+               s[i] = new_stmt(cstate, BPF_MISC|BPF_TAX);
                i++;
                /* A = MEM[reg2] */
-               s[i] = new_stmt(BPF_LD|BPF_MEM);
+               s[i] = new_stmt(cstate, BPF_LD|BPF_MEM);
                s[i]->s.k = reg2;
                i++;
 
                /* goto again; (must use BPF_JA for backward jump) */
-               s[i] = new_stmt(BPF_JMP|BPF_JA);
+               s[i] = new_stmt(cstate, BPF_JMP|BPF_JA);
                s[i]->s.k = again - i - 1;
                s[i - 1]->s.jf = s[i];
                i++;
@@ -5827,7 +5783,7 @@ gen_protochain(v, proto, dir)
                        s[j]->s.jt = s[v6advance];
        } else {
                /* nop */
-               s[i] = new_stmt(BPF_ALU|BPF_ADD|BPF_K);
+               s[i] = new_stmt(cstate, BPF_ALU|BPF_ADD|BPF_K);
                s[i]->s.k = 0;
                s[fix2]->s.jf = s[i];
                i++;
@@ -5836,7 +5792,7 @@ gen_protochain(v, proto, dir)
        /* ahcheck: */
        ahcheck = i;
        /* if (A == IPPROTO_AH) then fall through; else goto end; */
-       s[i] = new_stmt(BPF_JMP|BPF_JEQ|BPF_K);
+       s[i] = new_stmt(cstate, BPF_JMP|BPF_JEQ|BPF_K);
        s[i]->s.jt = NULL;      /*later*/
        s[i]->s.jf = NULL;      /*later*/
        s[i]->s.k = IPPROTO_AH;
@@ -5851,54 +5807,54 @@ gen_protochain(v, proto, dir)
         * X = X + (P[X + 1] + 2) * 4;
         */
        /* A = X */
-       s[i - 1]->s.jt = s[i] = new_stmt(BPF_MISC|BPF_TXA);
+       s[i - 1]->s.jt = s[i] = new_stmt(cstate, BPF_MISC|BPF_TXA);
        i++;
        /* A = P[X + packet head]; */
-       s[i] = new_stmt(BPF_LD|BPF_IND|BPF_B);
-       s[i]->s.k = off_linkpl.constant_part + off_nl;
+       s[i] = new_stmt(cstate, BPF_LD|BPF_IND|BPF_B);
+       s[i]->s.k = cstate->off_linkpl.constant_part + cstate->off_nl;
        i++;
        /* MEM[reg2] = A */
-       s[i] = new_stmt(BPF_ST);
+       s[i] = new_stmt(cstate, BPF_ST);
        s[i]->s.k = reg2;
        i++;
        /* A = X */
-       s[i - 1]->s.jt = s[i] = new_stmt(BPF_MISC|BPF_TXA);
+       s[i - 1]->s.jt = s[i] = new_stmt(cstate, BPF_MISC|BPF_TXA);
        i++;
        /* A += 1 */
-       s[i] = new_stmt(BPF_ALU|BPF_ADD|BPF_K);
+       s[i] = new_stmt(cstate, BPF_ALU|BPF_ADD|BPF_K);
        s[i]->s.k = 1;
        i++;
        /* X = A */
-       s[i] = new_stmt(BPF_MISC|BPF_TAX);
+       s[i] = new_stmt(cstate, BPF_MISC|BPF_TAX);
        i++;
        /* A = P[X + packet head] */
-       s[i] = new_stmt(BPF_LD|BPF_IND|BPF_B);
-       s[i]->s.k = off_linkpl.constant_part + off_nl;
+       s[i] = new_stmt(cstate, BPF_LD|BPF_IND|BPF_B);
+       s[i]->s.k = cstate->off_linkpl.constant_part + cstate->off_nl;
        i++;
        /* A += 2 */
-       s[i] = new_stmt(BPF_ALU|BPF_ADD|BPF_K);
+       s[i] = new_stmt(cstate, BPF_ALU|BPF_ADD|BPF_K);
        s[i]->s.k = 2;
        i++;
        /* A *= 4 */
-       s[i] = new_stmt(BPF_ALU|BPF_MUL|BPF_K);
+       s[i] = new_stmt(cstate, BPF_ALU|BPF_MUL|BPF_K);
        s[i]->s.k = 4;
        i++;
        /* X = A; */
-       s[i] = new_stmt(BPF_MISC|BPF_TAX);
+       s[i] = new_stmt(cstate, BPF_MISC|BPF_TAX);
        i++;
        /* A = MEM[reg2] */
-       s[i] = new_stmt(BPF_LD|BPF_MEM);
+       s[i] = new_stmt(cstate, BPF_LD|BPF_MEM);
        s[i]->s.k = reg2;
        i++;
 
        /* goto again; (must use BPF_JA for backward jump) */
-       s[i] = new_stmt(BPF_JMP|BPF_JA);
+       s[i] = new_stmt(cstate, BPF_JMP|BPF_JA);
        s[i]->s.k = again - i - 1;
        i++;
 
        /* end: nop */
        end = i;
-       s[i] = new_stmt(BPF_ALU|BPF_ADD|BPF_K);
+       s[i] = new_stmt(cstate, BPF_ALU|BPF_ADD|BPF_K);
        s[i]->s.k = 0;
        s[fix2]->s.jt = s[end];
        s[fix4]->s.jf = s[end];
@@ -5916,11 +5872,11 @@ gen_protochain(v, proto, dir)
        /*
         * emit final check
         */
-       b = new_block(JMP(BPF_JEQ));
+       b = new_block(cstate, JMP(BPF_JEQ));
        b->stmts = s[1];        /*remember, s[0] is dummy*/
        b->s.k = v;
 
-       free_reg(reg2);
+       free_reg(cstate, reg2);
 
        gen_and(b0, b);
        return b;
@@ -5928,7 +5884,7 @@ gen_protochain(v, proto, dir)
 }
 
 static struct block *
-gen_check_802_11_data_frame()
+gen_check_802_11_data_frame(compiler_state_t *cstate)
 {
        struct slist *s;
        struct block *b0, *b1;
@@ -5937,13 +5893,13 @@ gen_check_802_11_data_frame()
         * A data frame has the 0x08 bit (b3) in the frame control field set
         * and the 0x04 bit (b2) clear.
         */
-       s = gen_load_a(OR_LINKHDR, 0, BPF_B);
-       b0 = new_block(JMP(BPF_JSET));
+       s = gen_load_a(cstate, OR_LINKHDR, 0, BPF_B);
+       b0 = new_block(cstate, JMP(BPF_JSET));
        b0->s.k = 0x08;
        b0->stmts = s;
 
-       s = gen_load_a(OR_LINKHDR, 0, BPF_B);
-       b1 = new_block(JMP(BPF_JSET));
+       s = gen_load_a(cstate, OR_LINKHDR, 0, BPF_B);
+       b1 = new_block(cstate, JMP(BPF_JSET));
        b1->s.k = 0x04;
        b1->stmts = s;
        gen_not(b1);
@@ -5963,10 +5919,7 @@ gen_check_802_11_data_frame()
  * against Q_IP and Q_IPV6.
  */
 static struct block *
-gen_proto(v, proto, dir)
-       int v;
-       int proto;
-       int dir;
+gen_proto(compiler_state_t *cstate, int v, int proto, int dir)
 {
        struct block *b0, *b1;
 #ifndef CHASE_CHAIN
@@ -5974,12 +5927,12 @@ gen_proto(v, proto, dir)
 #endif
 
        if (dir != Q_DEFAULT)
-               bpf_error("direction applied to 'proto'");
+               bpf_error(cstate, "direction applied to 'proto'");
 
        switch (proto) {
        case Q_DEFAULT:
-               b0 = gen_proto(v, Q_IP, dir);
-               b1 = gen_proto(v, Q_IPV6, dir);
+               b0 = gen_proto(cstate, v, Q_IP, dir);
+               b1 = gen_proto(cstate, v, Q_IPV6, dir);
                gen_or(b0, b1);
                return b1;
 
@@ -5999,22 +5952,22 @@ gen_proto(v, proto, dir)
                 *
                 * So we always check for ETHERTYPE_IP.
                 */
-               b0 = gen_linktype(ETHERTYPE_IP);
+               b0 = gen_linktype(cstate, ETHERTYPE_IP);
 #ifndef CHASE_CHAIN
-               b1 = gen_cmp(OR_LINKPL, 9, BPF_B, (bpf_int32)v);
+               b1 = gen_cmp(cstate, OR_LINKPL, 9, BPF_B, (bpf_int32)v);
 #else
-               b1 = gen_protochain(v, Q_IP);
+               b1 = gen_protochain(cstate, v, Q_IP);
 #endif
                gen_and(b0, b1);
                return b1;
 
        case Q_ISO:
-               switch (linktype) {
+               switch (cstate->linktype) {
 
                case DLT_FRELAY:
                        /*
                         * Frame Relay packets typically have an OSI
-                        * NLPID at the beginning; "gen_linktype(LLCSAP_ISONS)"
+                        * NLPID at the beginning; "gen_linktype(cstate, LLCSAP_ISONS)"
                         * generates code to check for all the OSI
                         * NLPIDs, so calling it and then adding a check
                         * for the particular NLPID for which we're
@@ -6030,7 +5983,7 @@ gen_proto(v, proto, dir)
                         *
                         * XXX - what about SNAP-encapsulated frames?
                         */
-                       return gen_cmp(OR_LINKHDR, 2, BPF_H, (0x03<<8) | v);
+                       return gen_cmp(cstate, OR_LINKHDR, 2, BPF_H, (0x03<<8) | v);
                        /*NOTREACHED*/
                        break;
 
@@ -6039,138 +5992,138 @@ gen_proto(v, proto, dir)
                         * Cisco uses an Ethertype lookalike - for OSI,
                         * it's 0xfefe.
                         */
-                       b0 = gen_linktype(LLCSAP_ISONS<<8 | LLCSAP_ISONS);
+                       b0 = gen_linktype(cstate, LLCSAP_ISONS<<8 | LLCSAP_ISONS);
                        /* OSI in C-HDLC is stuffed with a fudge byte */
-                       b1 = gen_cmp(OR_LINKPL_NOSNAP, 1, BPF_B, (long)v);
+                       b1 = gen_cmp(cstate, OR_LINKPL_NOSNAP, 1, BPF_B, (long)v);
                        gen_and(b0, b1);
                        return b1;
 
                default:
-                       b0 = gen_linktype(LLCSAP_ISONS);
-                       b1 = gen_cmp(OR_LINKPL_NOSNAP, 0, BPF_B, (long)v);
+                       b0 = gen_linktype(cstate, LLCSAP_ISONS);
+                       b1 = gen_cmp(cstate, OR_LINKPL_NOSNAP, 0, BPF_B, (long)v);
                        gen_and(b0, b1);
                        return b1;
                }
 
        case Q_ISIS:
-               b0 = gen_proto(ISO10589_ISIS, Q_ISO, Q_DEFAULT);
+               b0 = gen_proto(cstate, ISO10589_ISIS, Q_ISO, Q_DEFAULT);
                /*
                 * 4 is the offset of the PDU type relative to the IS-IS
                 * header.
                 */
-               b1 = gen_cmp(OR_LINKPL_NOSNAP, 4, BPF_B, (long)v);
+               b1 = gen_cmp(cstate, OR_LINKPL_NOSNAP, 4, BPF_B, (long)v);
                gen_and(b0, b1);
                return b1;
 
        case Q_ARP:
-               bpf_error("arp does not encapsulate another protocol");
+               bpf_error(cstate, "arp does not encapsulate another protocol");
                /* NOTREACHED */
 
        case Q_RARP:
-               bpf_error("rarp does not encapsulate another protocol");
+               bpf_error(cstate, "rarp does not encapsulate another protocol");
                /* NOTREACHED */
 
        case Q_ATALK:
-               bpf_error("atalk encapsulation is not specifiable");
+               bpf_error(cstate, "atalk encapsulation is not specifiable");
                /* NOTREACHED */
 
        case Q_DECNET:
-               bpf_error("decnet encapsulation is not specifiable");
+               bpf_error(cstate, "decnet encapsulation is not specifiable");
                /* NOTREACHED */
 
        case Q_SCA:
-               bpf_error("sca does not encapsulate another protocol");
+               bpf_error(cstate, "sca does not encapsulate another protocol");
                /* NOTREACHED */
 
        case Q_LAT:
-               bpf_error("lat does not encapsulate another protocol");
+               bpf_error(cstate, "lat does not encapsulate another protocol");
                /* NOTREACHED */
 
        case Q_MOPRC:
-               bpf_error("moprc does not encapsulate another protocol");
+               bpf_error(cstate, "moprc does not encapsulate another protocol");
                /* NOTREACHED */
 
        case Q_MOPDL:
-               bpf_error("mopdl does not encapsulate another protocol");
+               bpf_error(cstate, "mopdl does not encapsulate another protocol");
                /* NOTREACHED */
 
        case Q_LINK:
-               return gen_linktype(v);
+               return gen_linktype(cstate, v);
 
        case Q_UDP:
-               bpf_error("'udp proto' is bogus");
+               bpf_error(cstate, "'udp proto' is bogus");
                /* NOTREACHED */
 
        case Q_TCP:
-               bpf_error("'tcp proto' is bogus");
+               bpf_error(cstate, "'tcp proto' is bogus");
                /* NOTREACHED */
 
        case Q_SCTP:
-               bpf_error("'sctp proto' is bogus");
+               bpf_error(cstate, "'sctp proto' is bogus");
                /* NOTREACHED */
 
        case Q_ICMP:
-               bpf_error("'icmp proto' is bogus");
+               bpf_error(cstate, "'icmp proto' is bogus");
                /* NOTREACHED */
 
        case Q_IGMP:
-               bpf_error("'igmp proto' is bogus");
+               bpf_error(cstate, "'igmp proto' is bogus");
                /* NOTREACHED */
 
        case Q_IGRP:
-               bpf_error("'igrp proto' is bogus");
+               bpf_error(cstate, "'igrp proto' is bogus");
                /* NOTREACHED */
 
        case Q_PIM:
-               bpf_error("'pim proto' is bogus");
+               bpf_error(cstate, "'pim proto' is bogus");
                /* NOTREACHED */
 
        case Q_VRRP:
-               bpf_error("'vrrp proto' is bogus");
+               bpf_error(cstate, "'vrrp proto' is bogus");
                /* NOTREACHED */
 
        case Q_CARP:
-               bpf_error("'carp proto' is bogus");
+               bpf_error(cstate, "'carp proto' is bogus");
                /* NOTREACHED */
 
        case Q_IPV6:
-               b0 = gen_linktype(ETHERTYPE_IPV6);
+               b0 = gen_linktype(cstate, ETHERTYPE_IPV6);
 #ifndef CHASE_CHAIN
                /*
                 * Also check for a fragment header before the final
                 * header.
                 */
-               b2 = gen_cmp(OR_LINKPL, 6, BPF_B, IPPROTO_FRAGMENT);
-               b1 = gen_cmp(OR_LINKPL, 40, BPF_B, (bpf_int32)v);
+               b2 = gen_cmp(cstate, OR_LINKPL, 6, BPF_B, IPPROTO_FRAGMENT);
+               b1 = gen_cmp(cstate, OR_LINKPL, 40, BPF_B, (bpf_int32)v);
                gen_and(b2, b1);
-               b2 = gen_cmp(OR_LINKPL, 6, BPF_B, (bpf_int32)v);
+               b2 = gen_cmp(cstate, OR_LINKPL, 6, BPF_B, (bpf_int32)v);
                gen_or(b2, b1);
 #else
-               b1 = gen_protochain(v, Q_IPV6);
+               b1 = gen_protochain(cstate, v, Q_IPV6);
 #endif
                gen_and(b0, b1);
                return b1;
 
        case Q_ICMPV6:
-               bpf_error("'icmp6 proto' is bogus");
+               bpf_error(cstate, "'icmp6 proto' is bogus");
 
        case Q_AH:
-               bpf_error("'ah proto' is bogus");
+               bpf_error(cstate, "'ah proto' is bogus");
 
        case Q_ESP:
-               bpf_error("'ah proto' is bogus");
+               bpf_error(cstate, "'ah proto' is bogus");
 
        case Q_STP:
-               bpf_error("'stp proto' is bogus");
+               bpf_error(cstate, "'stp proto' is bogus");
 
        case Q_IPX:
-               bpf_error("'ipx proto' is bogus");
+               bpf_error(cstate, "'ipx proto' is bogus");
 
        case Q_NETBEUI:
-               bpf_error("'netbeui proto' is bogus");
+               bpf_error(cstate, "'netbeui proto' is bogus");
 
        case Q_RADIO:
-               bpf_error("'radio proto' is bogus");
+               bpf_error(cstate, "'radio proto' is bogus");
 
        default:
                abort();
@@ -6180,9 +6133,7 @@ gen_proto(v, proto, dir)
 }
 
 struct block *
-gen_scode(name, q)
-       register const char *name;
-       struct qual q;
+gen_scode(compiler_state_t *cstate, const char *name, struct qual q)
 {
        int proto = q.proto;
        int dir = q.dir;
@@ -6207,29 +6158,29 @@ gen_scode(name, q)
        case Q_NET:
                addr = pcap_nametonetaddr(name);
                if (addr == 0)
-                       bpf_error("unknown network '%s'", name);
+                       bpf_error(cstate, "unknown network '%s'", name);
                /* Left justify network addr and calculate its network mask */
                mask = 0xffffffff;
                while (addr && (addr & 0xff000000) == 0) {
                        addr <<= 8;
                        mask <<= 8;
                }
-               return gen_host(addr, mask, proto, dir, q.addr);
+               return gen_host(cstate, addr, mask, proto, dir, q.addr);
 
        case Q_DEFAULT:
        case Q_HOST:
                if (proto == Q_LINK) {
-                       switch (linktype) {
+                       switch (cstate->linktype) {
 
                        case DLT_EN10MB:
                        case DLT_NETANALYZER:
                        case DLT_NETANALYZER_TRANSPARENT:
                                eaddr = pcap_ether_hostton(name);
                                if (eaddr == NULL)
-                                       bpf_error(
+                                       bpf_error(cstate,
                                            "unknown ether host '%s'", name);
-                               tmp = gen_prevlinkhdr_check();
-                               b = gen_ehostop(eaddr, dir);
+                               tmp = gen_prevlinkhdr_check(cstate);
+                               b = gen_ehostop(cstate, eaddr, dir);
                                if (tmp != NULL)
                                        gen_and(tmp, b);
                                free(eaddr);
@@ -6238,18 +6189,18 @@ gen_scode(name, q)
                        case DLT_FDDI:
                                eaddr = pcap_ether_hostton(name);
                                if (eaddr == NULL)
-                                       bpf_error(
+                                       bpf_error(cstate,
                                            "unknown FDDI host '%s'", name);
-                               b = gen_fhostop(eaddr, dir);
+                               b = gen_fhostop(cstate, eaddr, dir);
                                free(eaddr);
                                return b;
 
                        case DLT_IEEE802:
                                eaddr = pcap_ether_hostton(name);
                                if (eaddr == NULL)
-                                       bpf_error(
+                                       bpf_error(cstate,
                                            "unknown token ring host '%s'", name);
-                               b = gen_thostop(eaddr, dir);
+                               b = gen_thostop(cstate, eaddr, dir);
                                free(eaddr);
                                return b;
 
@@ -6260,42 +6211,51 @@ gen_scode(name, q)
                        case DLT_PPI:
                                eaddr = pcap_ether_hostton(name);
                                if (eaddr == NULL)
-                                       bpf_error(
+                                       bpf_error(cstate,
                                            "unknown 802.11 host '%s'", name);
-                               b = gen_wlanhostop(eaddr, dir);
+                               b = gen_wlanhostop(cstate, eaddr, dir);
                                free(eaddr);
                                return b;
 
                        case DLT_IP_OVER_FC:
                                eaddr = pcap_ether_hostton(name);
                                if (eaddr == NULL)
-                                       bpf_error(
+                                       bpf_error(cstate,
                                            "unknown Fibre Channel host '%s'", name);
-                               b = gen_ipfchostop(eaddr, dir);
+                               b = gen_ipfchostop(cstate, eaddr, dir);
                                free(eaddr);
                                return b;
                        }
 
-                       bpf_error("only ethernet/FDDI/token ring/802.11/ATM LANE/Fibre Channel supports link-level host name");
+                       bpf_error(cstate, "only ethernet/FDDI/token ring/802.11/ATM LANE/Fibre Channel supports link-level host name");
                } else if (proto == Q_DECNET) {
-                       unsigned short dn_addr = __pcap_nametodnaddr(name);
+                       unsigned short dn_addr;
+
+                       if (!__pcap_nametodnaddr(name, &dn_addr)) {
+#ifdef DECNETLIB
+                               bpf_error(cstate, "unknown decnet host name '%s'\n", name);
+#else
+                               bpf_error(cstate, "decnet name support not included, '%s' cannot be translated\n",
+                                       name);
+#endif
+                       }
                        /*
                         * I don't think DECNET hosts can be multihomed, so
                         * there is no need to build up a list of addresses
                         */
-                       return (gen_host(dn_addr, 0, proto, dir, q.addr));
+                       return (gen_host(cstate, dn_addr, 0, proto, dir, q.addr));
                } else {
 #ifndef INET6
                        alist = pcap_nametoaddr(name);
                        if (alist == NULL || *alist == NULL)
-                               bpf_error("unknown host '%s'", name);
+                               bpf_error(cstate, "unknown host '%s'", name);
                        tproto = proto;
-                       if (off_linktype.constant_part == (u_int)-1 &&
+                       if (cstate->off_linktype.constant_part == (u_int)-1 &&
                            tproto == Q_DEFAULT)
                                tproto = Q_IP;
-                       b = gen_host(**alist++, 0xffffffff, tproto, dir, q.addr);
+                       b = gen_host(cstate, **alist++, 0xffffffff, tproto, dir, q.addr);
                        while (*alist) {
-                               tmp = gen_host(**alist++, 0xffffffff,
+                               tmp = gen_host(cstate, **alist++, 0xffffffff,
                                               tproto, dir, q.addr);
                                gen_or(b, tmp);
                                b = tmp;
@@ -6305,11 +6265,11 @@ gen_scode(name, q)
                        memset(&mask128, 0xff, sizeof(mask128));
                        res0 = res = pcap_nametoaddrinfo(name);
                        if (res == NULL)
-                               bpf_error("unknown host '%s'", name);
-                       ai = res;
+                               bpf_error(cstate, "unknown host '%s'", name);
+                       cstate->ai = res;
                        b = tmp = NULL;
                        tproto = tproto6 = proto;
-                       if (off_linktype.constant_part == -1 &&
+                       if (cstate->off_linktype.constant_part == -1 &&
                            tproto == Q_DEFAULT) {
                                tproto = Q_IP;
                                tproto6 = Q_IPV6;
@@ -6322,7 +6282,7 @@ gen_scode(name, q)
 
                                        sin4 = (struct sockaddr_in *)
                                                res->ai_addr;
-                                       tmp = gen_host(ntohl(sin4->sin_addr.s_addr),
+                                       tmp = gen_host(cstate, ntohl(sin4->sin_addr.s_addr),
                                                0xffffffff, tproto, dir, q.addr);
                                        break;
                                case AF_INET6:
@@ -6331,7 +6291,7 @@ gen_scode(name, q)
 
                                        sin6 = (struct sockaddr_in6 *)
                                                res->ai_addr;
-                                       tmp = gen_host6(&sin6->sin6_addr,
+                                       tmp = gen_host6(cstate, &sin6->sin6_addr,
                                                &mask128, tproto6, dir, q.addr);
                                        break;
                                default:
@@ -6341,10 +6301,10 @@ gen_scode(name, q)
                                        gen_or(b, tmp);
                                b = tmp;
                        }
-                       ai = NULL;
+                       cstate->ai = NULL;
                        freeaddrinfo(res0);
                        if (b == NULL) {
-                               bpf_error("unknown host '%s'%s", name,
+                               bpf_error(cstate, "unknown host '%s'%s", name,
                                    (proto == Q_DEFAULT)
                                        ? ""
                                        : " for specified address family");
@@ -6356,124 +6316,124 @@ gen_scode(name, q)
        case Q_PORT:
                if (proto != Q_DEFAULT &&
                    proto != Q_UDP && proto != Q_TCP && proto != Q_SCTP)
-                       bpf_error("illegal qualifier of 'port'");
+                       bpf_error(cstate, "illegal qualifier of 'port'");
                if (pcap_nametoport(name, &port, &real_proto) == 0)
-                       bpf_error("unknown port '%s'", name);
+                       bpf_error(cstate, "unknown port '%s'", name);
                if (proto == Q_UDP) {
                        if (real_proto == IPPROTO_TCP)
-                               bpf_error("port '%s' is tcp", name);
+                               bpf_error(cstate, "port '%s' is tcp", name);
                        else if (real_proto == IPPROTO_SCTP)
-                               bpf_error("port '%s' is sctp", name);
+                               bpf_error(cstate, "port '%s' is sctp", name);
                        else
                                /* override PROTO_UNDEF */
                                real_proto = IPPROTO_UDP;
                }
                if (proto == Q_TCP) {
                        if (real_proto == IPPROTO_UDP)
-                               bpf_error("port '%s' is udp", name);
+                               bpf_error(cstate, "port '%s' is udp", name);
 
                        else if (real_proto == IPPROTO_SCTP)
-                               bpf_error("port '%s' is sctp", name);
+                               bpf_error(cstate, "port '%s' is sctp", name);
                        else
                                /* override PROTO_UNDEF */
                                real_proto = IPPROTO_TCP;
                }
                if (proto == Q_SCTP) {
                        if (real_proto == IPPROTO_UDP)
-                               bpf_error("port '%s' is udp", name);
+                               bpf_error(cstate, "port '%s' is udp", name);
 
                        else if (real_proto == IPPROTO_TCP)
-                               bpf_error("port '%s' is tcp", name);
+                               bpf_error(cstate, "port '%s' is tcp", name);
                        else
                                /* override PROTO_UNDEF */
                                real_proto = IPPROTO_SCTP;
                }
                if (port < 0)
-                       bpf_error("illegal port number %d < 0", port);
+                       bpf_error(cstate, "illegal port number %d < 0", port);
                if (port > 65535)
-                       bpf_error("illegal port number %d > 65535", port);
-               b = gen_port(port, real_proto, dir);
-               gen_or(gen_port6(port, real_proto, dir), b);
+                       bpf_error(cstate, "illegal port number %d > 65535", port);
+               b = gen_port(cstate, port, real_proto, dir);
+               gen_or(gen_port6(cstate, port, real_proto, dir), b);
                return b;
 
        case Q_PORTRANGE:
                if (proto != Q_DEFAULT &&
                    proto != Q_UDP && proto != Q_TCP && proto != Q_SCTP)
-                       bpf_error("illegal qualifier of 'portrange'");
+                       bpf_error(cstate, "illegal qualifier of 'portrange'");
                if (pcap_nametoportrange(name, &port1, &port2, &real_proto) == 0)
-                       bpf_error("unknown port in range '%s'", name);
+                       bpf_error(cstate, "unknown port in range '%s'", name);
                if (proto == Q_UDP) {
                        if (real_proto == IPPROTO_TCP)
-                               bpf_error("port in range '%s' is tcp", name);
+                               bpf_error(cstate, "port in range '%s' is tcp", name);
                        else if (real_proto == IPPROTO_SCTP)
-                               bpf_error("port in range '%s' is sctp", name);
+                               bpf_error(cstate, "port in range '%s' is sctp", name);
                        else
                                /* override PROTO_UNDEF */
                                real_proto = IPPROTO_UDP;
                }
                if (proto == Q_TCP) {
                        if (real_proto == IPPROTO_UDP)
-                               bpf_error("port in range '%s' is udp", name);
+                               bpf_error(cstate, "port in range '%s' is udp", name);
                        else if (real_proto == IPPROTO_SCTP)
-                               bpf_error("port in range '%s' is sctp", name);
+                               bpf_error(cstate, "port in range '%s' is sctp", name);
                        else
                                /* override PROTO_UNDEF */
                                real_proto = IPPROTO_TCP;
                }
                if (proto == Q_SCTP) {
                        if (real_proto == IPPROTO_UDP)
-                               bpf_error("port in range '%s' is udp", name);
+                               bpf_error(cstate, "port in range '%s' is udp", name);
                        else if (real_proto == IPPROTO_TCP)
-                               bpf_error("port in range '%s' is tcp", name);
+                               bpf_error(cstate, "port in range '%s' is tcp", name);
                        else
                                /* override PROTO_UNDEF */
                                real_proto = IPPROTO_SCTP;
                }
                if (port1 < 0)
-                       bpf_error("illegal port number %d < 0", port1);
+                       bpf_error(cstate, "illegal port number %d < 0", port1);
                if (port1 > 65535)
-                       bpf_error("illegal port number %d > 65535", port1);
+                       bpf_error(cstate, "illegal port number %d > 65535", port1);
                if (port2 < 0)
-                       bpf_error("illegal port number %d < 0", port2);
+                       bpf_error(cstate, "illegal port number %d < 0", port2);
                if (port2 > 65535)
-                       bpf_error("illegal port number %d > 65535", port2);
+                       bpf_error(cstate, "illegal port number %d > 65535", port2);
 
-               b = gen_portrange(port1, port2, real_proto, dir);
-               gen_or(gen_portrange6(port1, port2, real_proto, dir), b);
+               b = gen_portrange(cstate, port1, port2, real_proto, dir);
+               gen_or(gen_portrange6(cstate, port1, port2, real_proto, dir), b);
                return b;
 
        case Q_GATEWAY:
 #ifndef INET6
                eaddr = pcap_ether_hostton(name);
                if (eaddr == NULL)
-                       bpf_error("unknown ether host: %s", name);
+                       bpf_error(cstate, "unknown ether host: %s", name);
 
                alist = pcap_nametoaddr(name);
                if (alist == NULL || *alist == NULL)
-                       bpf_error("unknown host '%s'", name);
+                       bpf_error(cstate, "unknown host '%s'", name);
                b = gen_gateway(eaddr, alist, proto, dir);
                free(eaddr);
                return b;
 #else
-               bpf_error("'gateway' not supported in this configuration");
+               bpf_error(cstate, "'gateway' not supported in this configuration");
 #endif /*INET6*/
 
        case Q_PROTO:
-               real_proto = lookup_proto(name, proto);
+               real_proto = lookup_proto(cstate, name, proto);
                if (real_proto >= 0)
-                       return gen_proto(real_proto, proto, dir);
+                       return gen_proto(cstate, real_proto, proto, dir);
                else
-                       bpf_error("unknown protocol: %s", name);
+                       bpf_error(cstate, "unknown protocol: %s", name);
 
        case Q_PROTOCHAIN:
-               real_proto = lookup_proto(name, proto);
+               real_proto = lookup_proto(cstate, name, proto);
                if (real_proto >= 0)
-                       return gen_protochain(real_proto, proto, dir);
+                       return gen_protochain(cstate, real_proto, proto, dir);
                else
-                       bpf_error("unknown protocol: %s", name);
+                       bpf_error(cstate, "unknown protocol: %s", name);
 
        case Q_UNDEF:
-               syntax();
+               syntax(cstate);
                /* NOTREACHED */
        }
        abort();
@@ -6481,10 +6441,8 @@ gen_scode(name, q)
 }
 
 struct block *
-gen_mcode(s1, s2, masklen, q)
-       register const char *s1, *s2;
-       register unsigned int masklen;
-       struct qual q;
+gen_mcode(compiler_state_t *cstate, const char *s1, const char *s2,
+    unsigned int masklen, struct qual q)
 {
        register int nlen, mlen;
        bpf_u_int32 n, m;
@@ -6498,12 +6456,12 @@ gen_mcode(s1, s2, masklen, q)
                /* Promote short ipaddr */
                m <<= 32 - mlen;
                if ((n & ~m) != 0)
-                       bpf_error("non-network bits set in \"%s mask %s\"",
+                       bpf_error(cstate, "non-network bits set in \"%s mask %s\"",
                            s1, s2);
        } else {
                /* Convert mask len to mask */
                if (masklen > 32)
-                       bpf_error("mask length must be <= 32");
+                       bpf_error(cstate, "mask length must be <= 32");
                if (masklen == 0) {
                        /*
                         * X << 32 is not guaranteed by C to be 0; it's
@@ -6513,17 +6471,17 @@ gen_mcode(s1, s2, masklen, q)
                } else
                        m = 0xffffffff << (32 - masklen);
                if ((n & ~m) != 0)
-                       bpf_error("non-network bits set in \"%s/%d\"",
+                       bpf_error(cstate, "non-network bits set in \"%s/%d\"",
                            s1, masklen);
        }
 
        switch (q.addr) {
 
        case Q_NET:
-               return gen_host(n, m, q.proto, q.dir, q.addr);
+               return gen_host(cstate, n, m, q.proto, q.dir, q.addr);
 
        default:
-               bpf_error("Mask syntax for networks only");
+               bpf_error(cstate, "Mask syntax for networks only");
                /* NOTREACHED */
        }
        /* NOTREACHED */
@@ -6531,10 +6489,7 @@ gen_mcode(s1, s2, masklen, q)
 }
 
 struct block *
-gen_ncode(s, v, q)
-       register const char *s;
-       bpf_u_int32 v;
-       struct qual q;
+gen_ncode(compiler_state_t *cstate, const char *s, bpf_u_int32 v, struct qual q)
 {
        bpf_u_int32 mask;
        int proto = q.proto;
@@ -6543,9 +6498,11 @@ gen_ncode(s, v, q)
 
        if (s == NULL)
                vlen = 32;
-       else if (q.proto == Q_DECNET)
+       else if (q.proto == Q_DECNET) {
                vlen = __pcap_atodn(s, &v);
-       else
+               if (vlen == 0)
+                       bpf_error(cstate, "malformed decnet address '%s'", s);
+       } else
                vlen = __pcap_atoin(s, &v);
 
        switch (q.addr) {
@@ -6554,9 +6511,9 @@ gen_ncode(s, v, q)
        case Q_HOST:
        case Q_NET:
                if (proto == Q_DECNET)
-                       return gen_host(v, 0, proto, dir, q.addr);
+                       return gen_host(cstate, v, 0, proto, dir, q.addr);
                else if (proto == Q_LINK) {
-                       bpf_error("illegal link layer address");
+                       bpf_error(cstate, "illegal link layer address");
                } else {
                        mask = 0xffffffff;
                        if (s == NULL && q.addr == Q_NET) {
@@ -6568,9 +6525,9 @@ gen_ncode(s, v, q)
                        } else {
                                /* Promote short ipaddr */
                                v <<= 32 - vlen;
-                               mask <<= 32 - vlen;
+                               mask <<= 32 - vlen ;
                        }
-                       return gen_host(v, mask, proto, dir, q.addr);
+                       return gen_host(cstate, v, mask, proto, dir, q.addr);
                }
 
        case Q_PORT:
@@ -6583,15 +6540,15 @@ gen_ncode(s, v, q)
                else if (proto == Q_DEFAULT)
                        proto = PROTO_UNDEF;
                else
-                       bpf_error("illegal qualifier of 'port'");
+                       bpf_error(cstate, "illegal qualifier of 'port'");
 
                if (v > 65535)
-                       bpf_error("illegal port number %u > 65535", v);
+                       bpf_error(cstate, "illegal port number %u > 65535", v);
 
            {
                struct block *b;
-               b = gen_port((int)v, proto, dir);
-               gen_or(gen_port6((int)v, proto, dir), b);
+               b = gen_port(cstate, (int)v, proto, dir);
+               gen_or(gen_port6(cstate, (int)v, proto, dir), b);
                return b;
            }
 
@@ -6605,30 +6562,30 @@ gen_ncode(s, v, q)
                else if (proto == Q_DEFAULT)
                        proto = PROTO_UNDEF;
                else
-                       bpf_error("illegal qualifier of 'portrange'");
+                       bpf_error(cstate, "illegal qualifier of 'portrange'");
 
                if (v > 65535)
-                       bpf_error("illegal port number %u > 65535", v);
+                       bpf_error(cstate, "illegal port number %u > 65535", v);
 
            {
                struct block *b;
-               b = gen_portrange((int)v, (int)v, proto, dir);
-               gen_or(gen_portrange6((int)v, (int)v, proto, dir), b);
+               b = gen_portrange(cstate, (int)v, (int)v, proto, dir);
+               gen_or(gen_portrange6(cstate, (int)v, (int)v, proto, dir), b);
                return b;
            }
 
        case Q_GATEWAY:
-               bpf_error("'gateway' requires a name");
+               bpf_error(cstate, "'gateway' requires a name");
                /* NOTREACHED */
 
        case Q_PROTO:
-               return gen_proto((int)v, proto, dir);
+               return gen_proto(cstate, (int)v, proto, dir);
 
        case Q_PROTOCHAIN:
-               return gen_protochain((int)v, proto, dir);
+               return gen_protochain(cstate, (int)v, proto, dir);
 
        case Q_UNDEF:
-               syntax();
+               syntax(cstate);
                /* NOTREACHED */
 
        default:
@@ -6640,10 +6597,8 @@ gen_ncode(s, v, q)
 
 #ifdef INET6
 struct block *
-gen_mcode6(s1, s2, masklen, q)
-       register const char *s1, *s2;
-       register unsigned int masklen;
-       struct qual q;
+gen_mcode6(compiler_state_t *cstate, const char *s1, const char *s2,
+    unsigned int masklen, struct qual q)
 {
        struct addrinfo *res;
        struct in6_addr *addr;
@@ -6652,18 +6607,18 @@ gen_mcode6(s1, s2, masklen, q)
        u_int32_t *a, *m;
 
        if (s2)
-               bpf_error("no mask %s supported", s2);
+               bpf_error(cstate, "no mask %s supported", s2);
 
        res = pcap_nametoaddrinfo(s1);
        if (!res)
-               bpf_error("invalid ip6 address %s", s1);
-       ai = res;
+               bpf_error(cstate, "invalid ip6 address %s", s1);
+       cstate->ai = res;
        if (res->ai_next)
-               bpf_error("%s resolved to multiple address", s1);
+               bpf_error(cstate, "%s resolved to multiple address", s1);
        addr = &((struct sockaddr_in6 *)res->ai_addr)->sin6_addr;
 
        if (sizeof(mask) * 8 < masklen)
-               bpf_error("mask length must be <= %u", (unsigned int)(sizeof(mask) * 8));
+               bpf_error(cstate, "mask length must be <= %u", (unsigned int)(sizeof(mask) * 8));
        memset(&mask, 0, sizeof(mask));
        memset(&mask, 0xff, masklen / 8);
        if (masklen % 8) {
@@ -6675,7 +6630,7 @@ gen_mcode6(s1, s2, masklen, q)
        m = (u_int32_t *)&mask;
        if ((a[0] & ~m[0]) || (a[1] & ~m[1])
         || (a[2] & ~m[2]) || (a[3] & ~m[3])) {
-               bpf_error("non-network bits set in \"%s/%d\"", s1, masklen);
+               bpf_error(cstate, "non-network bits set in \"%s/%d\"", s1, masklen);
        }
 
        switch (q.addr) {
@@ -6683,17 +6638,17 @@ gen_mcode6(s1, s2, masklen, q)
        case Q_DEFAULT:
        case Q_HOST:
                if (masklen != 128)
-                       bpf_error("Mask syntax for networks only");
+                       bpf_error(cstate, "Mask syntax for networks only");
                /* FALLTHROUGH */
 
        case Q_NET:
-               b = gen_host6(addr, &mask, q.proto, q.dir, q.addr);
-               ai = NULL;
+               b = gen_host6(cstate, addr, &mask, q.proto, q.dir, q.addr);
+               cstate->ai = NULL;
                freeaddrinfo(res);
                return b;
 
        default:
-               bpf_error("invalid qualifier against IPv6 address");
+               bpf_error(cstate, "invalid qualifier against IPv6 address");
                /* NOTREACHED */
        }
        return NULL;
@@ -6701,40 +6656,38 @@ gen_mcode6(s1, s2, masklen, q)
 #endif /*INET6*/
 
 struct block *
-gen_ecode(eaddr, q)
-       register const u_char *eaddr;
-       struct qual q;
+gen_ecode(compiler_state_t *cstate, const u_char *eaddr, struct qual q)
 {
        struct block *b, *tmp;
 
        if ((q.addr == Q_HOST || q.addr == Q_DEFAULT) && q.proto == Q_LINK) {
-               switch (linktype) {
+               switch (cstate->linktype) {
                case DLT_EN10MB:
                case DLT_NETANALYZER:
                case DLT_NETANALYZER_TRANSPARENT:
-                       tmp = gen_prevlinkhdr_check();
-                       b = gen_ehostop(eaddr, (int)q.dir);
+                       tmp = gen_prevlinkhdr_check(cstate);
+                       b = gen_ehostop(cstate, eaddr, (int)q.dir);
                        if (tmp != NULL)
                                gen_and(tmp, b);
                        return b;
                case DLT_FDDI:
-                       return gen_fhostop(eaddr, (int)q.dir);
+                       return gen_fhostop(cstate, eaddr, (int)q.dir);
                case DLT_IEEE802:
-                       return gen_thostop(eaddr, (int)q.dir);
+                       return gen_thostop(cstate, eaddr, (int)q.dir);
                case DLT_IEEE802_11:
                case DLT_PRISM_HEADER:
                case DLT_IEEE802_11_RADIO_AVS:
                case DLT_IEEE802_11_RADIO:
                case DLT_PPI:
-                       return gen_wlanhostop(eaddr, (int)q.dir);
+                       return gen_wlanhostop(cstate, eaddr, (int)q.dir);
                case DLT_IP_OVER_FC:
-                       return gen_ipfchostop(eaddr, (int)q.dir);
+                       return gen_ipfchostop(cstate, eaddr, (int)q.dir);
                default:
-                       bpf_error("ethernet addresses supported only on ethernet/FDDI/token ring/802.11/ATM LANE/Fibre Channel");
+                       bpf_error(cstate, "ethernet addresses supported only on ethernet/FDDI/token ring/802.11/ATM LANE/Fibre Channel");
                        break;
                }
        }
-       bpf_error("ethernet address used in non-ether expression");
+       bpf_error(cstate, "ethernet address used in non-ether expression");
        /* NOTREACHED */
        return NULL;
 }
@@ -6753,23 +6706,21 @@ sappend(s0, s1)
 }
 
 static struct slist *
-xfer_to_x(a)
-       struct arth *a;
+xfer_to_x(compiler_state_t *cstate, struct arth *a)
 {
        struct slist *s;
 
-       s = new_stmt(BPF_LDX|BPF_MEM);
+       s = new_stmt(cstate, BPF_LDX|BPF_MEM);
        s->s.k = a->regno;
        return s;
 }
 
 static struct slist *
-xfer_to_a(a)
-       struct arth *a;
+xfer_to_a(compiler_state_t *cstate, struct arth *a)
 {
        struct slist *s;
 
-       s = new_stmt(BPF_LD|BPF_MEM);
+       s = new_stmt(cstate, BPF_LD|BPF_MEM);
        s->s.k = a->regno;
        return s;
 }
@@ -6782,20 +6733,17 @@ xfer_to_a(a)
  * for "index".
  */
 struct arth *
-gen_load(proto, inst, size)
-       int proto;
-       struct arth *inst;
-       int size;
+gen_load(compiler_state_t *cstate, int proto, struct arth *inst, int size)
 {
        struct slist *s, *tmp;
        struct block *b;
-       int regno = alloc_reg();
+       int regno = alloc_reg(cstate);
 
-       free_reg(inst->regno);
+       free_reg(cstate, inst->regno);
        switch (size) {
 
        default:
-               bpf_error("data size must be 1, 2, or 4");
+               bpf_error(cstate, "data size must be 1, 2, or 4");
 
        case 1:
                size = BPF_B;
@@ -6811,7 +6759,7 @@ gen_load(proto, inst, size)
        }
        switch (proto) {
        default:
-               bpf_error("unsupported index operation");
+               bpf_error(cstate, "unsupported index operation");
 
        case Q_RADIO:
                /*
@@ -6819,21 +6767,21 @@ gen_load(proto, inst, size)
                 * data, if we have a radio header.  (If we don't, this
                 * is an error.)
                 */
-               if (linktype != DLT_IEEE802_11_RADIO_AVS &&
-                   linktype != DLT_IEEE802_11_RADIO &&
-                   linktype != DLT_PRISM_HEADER)
-                       bpf_error("radio information not present in capture");
+               if (cstate->linktype != DLT_IEEE802_11_RADIO_AVS &&
+                   cstate->linktype != DLT_IEEE802_11_RADIO &&
+                   cstate->linktype != DLT_PRISM_HEADER)
+                       bpf_error(cstate, "radio information not present in capture");
 
                /*
                 * Load into the X register the offset computed into the
                 * register specified by "index".
                 */
-               s = xfer_to_x(inst);
+               s = xfer_to_x(cstate, inst);
 
                /*
                 * Load the item at that offset.
                 */
-               tmp = new_stmt(BPF_LD|BPF_IND|size);
+               tmp = new_stmt(cstate, BPF_LD|BPF_IND|size);
                sappend(s, tmp);
                sappend(inst->s, s);
                break;
@@ -6850,7 +6798,7 @@ gen_load(proto, inst, size)
                 * frame, so that 0 refers, for Ethernet LANE, to
                 * the beginning of the destination address?
                 */
-               s = gen_abs_offset_varpart(&off_linkhdr);
+               s = gen_abs_offset_varpart(cstate, &cstate->off_linkhdr);
 
                /*
                 * If "s" is non-null, it has code to arrange that the
@@ -6862,11 +6810,11 @@ gen_load(proto, inst, size)
                 * by "index".
                 */
                if (s != NULL) {
-                       sappend(s, xfer_to_a(inst));
-                       sappend(s, new_stmt(BPF_ALU|BPF_ADD|BPF_X));
-                       sappend(s, new_stmt(BPF_MISC|BPF_TAX));
+                       sappend(s, xfer_to_a(cstate, inst));
+                       sappend(s, new_stmt(cstate, BPF_ALU|BPF_ADD|BPF_X));
+                       sappend(s, new_stmt(cstate, BPF_MISC|BPF_TAX));
                } else
-                       s = xfer_to_x(inst);
+                       s = xfer_to_x(cstate, inst);
 
                /*
                 * Load the item at the sum of the offset we've put in the
@@ -6875,8 +6823,8 @@ gen_load(proto, inst, size)
                 * variable-length; that header length is what we put
                 * into the X register and then added to the index).
                 */
-               tmp = new_stmt(BPF_LD|BPF_IND|size);
-               tmp->s.k = off_linkhdr.constant_part;
+               tmp = new_stmt(cstate, BPF_LD|BPF_IND|size);
+               tmp->s.k = cstate->off_linkhdr.constant_part;
                sappend(s, tmp);
                sappend(inst->s, s);
                break;
@@ -6895,9 +6843,9 @@ gen_load(proto, inst, size)
                 * The offset is relative to the beginning of
                 * the network-layer header.
                 * XXX - are there any cases where we want
-                * off_nl_nosnap?
+                * cstate->off_nl_nosnap?
                 */
-               s = gen_abs_offset_varpart(&off_linkpl);
+               s = gen_abs_offset_varpart(cstate, &cstate->off_linkpl);
 
                /*
                 * If "s" is non-null, it has code to arrange that the
@@ -6909,11 +6857,11 @@ gen_load(proto, inst, size)
                 * the register specified by "index".
                 */
                if (s != NULL) {
-                       sappend(s, xfer_to_a(inst));
-                       sappend(s, new_stmt(BPF_ALU|BPF_ADD|BPF_X));
-                       sappend(s, new_stmt(BPF_MISC|BPF_TAX));
+                       sappend(s, xfer_to_a(cstate, inst));
+                       sappend(s, new_stmt(cstate, BPF_ALU|BPF_ADD|BPF_X));
+                       sappend(s, new_stmt(cstate, BPF_MISC|BPF_TAX));
                } else
-                       s = xfer_to_x(inst);
+                       s = xfer_to_x(cstate, inst);
 
                /*
                 * Load the item at the sum of the offset we've put in the
@@ -6922,8 +6870,8 @@ gen_load(proto, inst, size)
                 * payload, and the constant part of the offset of the
                 * start of the link-layer payload.
                 */
-               tmp = new_stmt(BPF_LD|BPF_IND|size);
-               tmp->s.k = off_linkpl.constant_part + off_nl;
+               tmp = new_stmt(cstate, BPF_LD|BPF_IND|size);
+               tmp->s.k = cstate->off_linkpl.constant_part + cstate->off_nl;
                sappend(s, tmp);
                sappend(inst->s, s);
 
@@ -6931,7 +6879,7 @@ gen_load(proto, inst, size)
                 * Do the computation only if the packet contains
                 * the protocol in question.
                 */
-               b = gen_proto_abbrev(proto);
+               b = gen_proto_abbrev(cstate, proto);
                if (inst->b)
                        gen_and(inst->b, b);
                inst->b = b;
@@ -6955,12 +6903,12 @@ gen_load(proto, inst, size)
                 * a variable-length header), in bytes.
                 *
                 * XXX - are there any cases where we want
-                * off_nl_nosnap?
+                * cstate->off_nl_nosnap?
                 * XXX - we should, if we're built with
                 * IPv6 support, generate code to load either
                 * IPv4, IPv6, or both, as appropriate.
                 */
-               s = gen_loadx_iphdrlen();
+               s = gen_loadx_iphdrlen(cstate);
 
                /*
                 * The X register now contains the sum of the variable
@@ -6976,11 +6924,11 @@ gen_load(proto, inst, size)
                 * relative to the beginning of the link-layer payload,
                 * of the network-layer header.
                 */
-               sappend(s, xfer_to_a(inst));
-               sappend(s, new_stmt(BPF_ALU|BPF_ADD|BPF_X));
-               sappend(s, new_stmt(BPF_MISC|BPF_TAX));
-               sappend(s, tmp = new_stmt(BPF_LD|BPF_IND|size));
-               tmp->s.k = off_linkpl.constant_part + off_nl;
+               sappend(s, xfer_to_a(cstate, inst));
+               sappend(s, new_stmt(cstate, BPF_ALU|BPF_ADD|BPF_X));
+               sappend(s, new_stmt(cstate, BPF_MISC|BPF_TAX));
+               sappend(s, tmp = new_stmt(cstate, BPF_LD|BPF_IND|size));
+               tmp->s.k = cstate->off_linkpl.constant_part + cstate->off_nl;
                sappend(inst->s, s);
 
                /*
@@ -6989,18 +6937,18 @@ gen_load(proto, inst, size)
                 * if this is an IP datagram and is the first or
                 * only fragment of that datagram.
                 */
-               gen_and(gen_proto_abbrev(proto), b = gen_ipfrag());
+               gen_and(gen_proto_abbrev(cstate, proto), b = gen_ipfrag(cstate));
                if (inst->b)
                        gen_and(inst->b, b);
-               gen_and(gen_proto_abbrev(Q_IP), b);
+               gen_and(gen_proto_abbrev(cstate, Q_IP), b);
                inst->b = b;
                break;
        case Q_ICMPV6:
-               bpf_error("IPv6 upper-layer protocol is not supported by proto[x]");
+               bpf_error(cstate, "IPv6 upper-layer protocol is not supported by proto[x]");
                /*NOTREACHED*/
        }
        inst->regno = regno;
-       s = new_stmt(BPF_ST);
+       s = new_stmt(cstate, BPF_ST);
        s->s.k = regno;
        sappend(inst->s, s);
 
@@ -7008,23 +6956,21 @@ gen_load(proto, inst, size)
 }
 
 struct block *
-gen_relation(code, a0, a1, reversed)
-       int code;
-       struct arth *a0, *a1;
-       int reversed;
+gen_relation(compiler_state_t *cstate, int code, struct arth *a0,
+    struct arth *a1, int reversed)
 {
        struct slist *s0, *s1, *s2;
        struct block *b, *tmp;
 
-       s0 = xfer_to_x(a1);
-       s1 = xfer_to_a(a0);
+       s0 = xfer_to_x(cstate, a1);
+       s1 = xfer_to_a(cstate, a0);
        if (code == BPF_JEQ) {
-               s2 = new_stmt(BPF_ALU|BPF_SUB|BPF_X);
-               b = new_block(JMP(code));
+               s2 = new_stmt(cstate, BPF_ALU|BPF_SUB|BPF_X);
+               b = new_block(cstate, JMP(code));
                sappend(s1, s2);
        }
        else
-               b = new_block(BPF_JMP|code|BPF_X);
+               b = new_block(cstate, BPF_JMP|code|BPF_X);
        if (reversed)
                gen_not(b);
 
@@ -7034,8 +6980,8 @@ gen_relation(code, a0, a1, reversed)
 
        b->stmts = a0->s;
 
-       free_reg(a0->regno);
-       free_reg(a1->regno);
+       free_reg(cstate, a0->regno);
+       free_reg(cstate, a1->regno);
 
        /* 'and' together protocol checks */
        if (a0->b) {
@@ -7054,14 +7000,14 @@ gen_relation(code, a0, a1, reversed)
 }
 
 struct arth *
-gen_loadlen()
+gen_loadlen(compiler_state_t *cstate)
 {
-       int regno = alloc_reg();
-       struct arth *a = (struct arth *)newchunk(sizeof(*a));
+       int regno = alloc_reg(cstate);
+       struct arth *a = (struct arth *)newchunk(cstate, sizeof(*a));
        struct slist *s;
 
-       s = new_stmt(BPF_LD|BPF_LEN);
-       s->next = new_stmt(BPF_ST);
+       s = new_stmt(cstate, BPF_LD|BPF_LEN);
+       s->next = new_stmt(cstate, BPF_ST);
        s->next->s.k = regno;
        a->s = s;
        a->regno = regno;
@@ -7070,20 +7016,19 @@ gen_loadlen()
 }
 
 struct arth *
-gen_loadi(val)
-       int val;
+gen_loadi(compiler_state_t *cstate, int val)
 {
        struct arth *a;
        struct slist *s;
        int reg;
 
-       a = (struct arth *)newchunk(sizeof(*a));
+       a = (struct arth *)newchunk(cstate, sizeof(*a));
 
-       reg = alloc_reg();
+       reg = alloc_reg(cstate);
 
-       s = new_stmt(BPF_LD|BPF_IMM);
+       s = new_stmt(cstate, BPF_LD|BPF_IMM);
        s->s.k = val;
-       s->next = new_stmt(BPF_ST);
+       s->next = new_stmt(cstate, BPF_ST);
        s->next->s.k = reg;
        a->s = s;
        a->regno = reg;
@@ -7092,17 +7037,16 @@ gen_loadi(val)
 }
 
 struct arth *
-gen_neg(a)
-       struct arth *a;
+gen_neg(compiler_state_t *cstate, struct arth *a)
 {
        struct slist *s;
 
-       s = xfer_to_a(a);
+       s = xfer_to_a(cstate, a);
        sappend(a->s, s);
-       s = new_stmt(BPF_ALU|BPF_NEG);
+       s = new_stmt(cstate, BPF_ALU|BPF_NEG);
        s->s.k = 0;
        sappend(a->s, s);
-       s = new_stmt(BPF_ST);
+       s = new_stmt(cstate, BPF_ST);
        s->s.k = a->regno;
        sappend(a->s, s);
 
@@ -7110,9 +7054,8 @@ gen_neg(a)
 }
 
 struct arth *
-gen_arth(code, a0, a1)
-       int code;
-       struct arth *a0, *a1;
+gen_arth(compiler_state_t *cstate, int code, struct arth *a0,
+    struct arth *a1)
 {
        struct slist *s0, *s1, *s2;
 
@@ -7122,64 +7065,57 @@ gen_arth(code, a0, a1)
         */
        if (code == BPF_DIV) {
                if (a1->s->s.code == (BPF_LD|BPF_IMM) && a1->s->s.k == 0)
-                       bpf_error("division by zero");
+                       bpf_error(cstate, "division by zero");
        } else if (code == BPF_MOD) {
                if (a1->s->s.code == (BPF_LD|BPF_IMM) && a1->s->s.k == 0)
-                       bpf_error("modulus by zero");
+                       bpf_error(cstate, "modulus by zero");
        }
-       s0 = xfer_to_x(a1);
-       s1 = xfer_to_a(a0);
-       s2 = new_stmt(BPF_ALU|BPF_X|code);
+       s0 = xfer_to_x(cstate, a1);
+       s1 = xfer_to_a(cstate, a0);
+       s2 = new_stmt(cstate, BPF_ALU|BPF_X|code);
 
        sappend(s1, s2);
        sappend(s0, s1);
        sappend(a1->s, s0);
        sappend(a0->s, a1->s);
 
-       free_reg(a0->regno);
-       free_reg(a1->regno);
+       free_reg(cstate, a0->regno);
+       free_reg(cstate, a1->regno);
 
-       s0 = new_stmt(BPF_ST);
-       a0->regno = s0->s.k = alloc_reg();
+       s0 = new_stmt(cstate, BPF_ST);
+       a0->regno = s0->s.k = alloc_reg(cstate);
        sappend(a0->s, s0);
 
        return a0;
 }
 
-/*
- * Here we handle simple allocation of the scratch registers.
- * If too many registers are alloc'd, the allocator punts.
- */
-static int regused[BPF_MEMWORDS];
-static int curreg;
-
 /*
  * Initialize the table of used registers and the current register.
  */
 static void
-init_regs()
+init_regs(compiler_state_t *cstate)
 {
-       curreg = 0;
-       memset(regused, 0, sizeof regused);
+       cstate->curreg = 0;
+       memset(cstate->regused, 0, sizeof cstate->regused);
 }
 
 /*
  * Return the next free register.
  */
 static int
-alloc_reg()
+alloc_reg(compiler_state_t *cstate)
 {
        int n = BPF_MEMWORDS;
 
        while (--n >= 0) {
-               if (regused[curreg])
-                       curreg = (curreg + 1) % BPF_MEMWORDS;
+               if (cstate->regused[cstate->curreg])
+                       cstate->curreg = (cstate->curreg + 1) % BPF_MEMWORDS;
                else {
-                       regused[curreg] = 1;
-                       return curreg;
+                       cstate->regused[cstate->curreg] = 1;
+                       return cstate->curreg;
                }
        }
-       bpf_error("too many registers needed to evaluate expression");
+       bpf_error(cstate, "too many registers needed to evaluate expression");
        /* NOTREACHED */
        return 0;
 }
@@ -7189,21 +7125,19 @@ alloc_reg()
  * be used later.
  */
 static void
-free_reg(n)
-       int n;
+free_reg(compiler_state_t *cstate, int n)
 {
-       regused[n] = 0;
+       cstate->regused[n] = 0;
 }
 
 static struct block *
-gen_len(jmp, n)
-       int jmp, n;
+gen_len(compiler_state_t *cstate, int jmp, int n)
 {
        struct slist *s;
        struct block *b;
 
-       s = new_stmt(BPF_LD|BPF_LEN);
-       b = new_block(JMP(jmp));
+       s = new_stmt(cstate, BPF_LD|BPF_LEN);
+       b = new_block(cstate, JMP(jmp));
        b->stmts = s;
        b->s.k = n;
 
@@ -7211,22 +7145,20 @@ gen_len(jmp, n)
 }
 
 struct block *
-gen_greater(n)
-       int n;
+gen_greater(compiler_state_t *cstate, int n)
 {
-       return gen_len(BPF_JGE, n);
+       return gen_len(cstate, BPF_JGE, n);
 }
 
 /*
  * Actually, this is less than or equal.
  */
 struct block *
-gen_less(n)
-       int n;
+gen_less(compiler_state_t *cstate, int n)
 {
        struct block *b;
 
-       b = gen_len(BPF_JGT, n);
+       b = gen_len(cstate, BPF_JGT, n);
        gen_not(b);
 
        return b;
@@ -7243,8 +7175,7 @@ gen_less(n)
  * would generate code appropriate to the radio header in question.
  */
 struct block *
-gen_byteop(op, idx, val)
-       int op, idx, val;
+gen_byteop(compiler_state_t *cstate, int op, int idx, int val)
 {
        struct block *b;
        struct slist *s;
@@ -7254,72 +7185,71 @@ gen_byteop(op, idx, val)
                abort();
 
        case '=':
-               return gen_cmp(OR_LINKHDR, (u_int)idx, BPF_B, (bpf_int32)val);
+               return gen_cmp(cstate, OR_LINKHDR, (u_int)idx, BPF_B, (bpf_int32)val);
 
        case '<':
-               b = gen_cmp_lt(OR_LINKHDR, (u_int)idx, BPF_B, (bpf_int32)val);
+               b = gen_cmp_lt(cstate, OR_LINKHDR, (u_int)idx, BPF_B, (bpf_int32)val);
                return b;
 
        case '>':
-               b = gen_cmp_gt(OR_LINKHDR, (u_int)idx, BPF_B, (bpf_int32)val);
+               b = gen_cmp_gt(cstate, OR_LINKHDR, (u_int)idx, BPF_B, (bpf_int32)val);
                return b;
 
        case '|':
-               s = new_stmt(BPF_ALU|BPF_OR|BPF_K);
+               s = new_stmt(cstate, BPF_ALU|BPF_OR|BPF_K);
                break;
 
        case '&':
-               s = new_stmt(BPF_ALU|BPF_AND|BPF_K);
+               s = new_stmt(cstate, BPF_ALU|BPF_AND|BPF_K);
                break;
        }
        s->s.k = val;
-       b = new_block(JMP(BPF_JEQ));
+       b = new_block(cstate, JMP(BPF_JEQ));
        b->stmts = s;
        gen_not(b);
 
        return b;
 }
 
-static u_char abroadcast[] = { 0x0 };
+static const u_char abroadcast[] = { 0x0 };
 
 struct block *
-gen_broadcast(proto)
-       int proto;
+gen_broadcast(compiler_state_t *cstate, int proto)
 {
        bpf_u_int32 hostmask;
        struct block *b0, *b1, *b2;
-       static u_char ebroadcast[] = { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
+       static const u_char ebroadcast[] = { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
 
        switch (proto) {
 
        case Q_DEFAULT:
        case Q_LINK:
-               switch (linktype) {
+               switch (cstate->linktype) {
                case DLT_ARCNET:
                case DLT_ARCNET_LINUX:
-                       return gen_ahostop(abroadcast, Q_DST);
+                       return gen_ahostop(cstate, abroadcast, Q_DST);
                case DLT_EN10MB:
                case DLT_NETANALYZER:
                case DLT_NETANALYZER_TRANSPARENT:
-                       b1 = gen_prevlinkhdr_check();
-                       b0 = gen_ehostop(ebroadcast, Q_DST);
+                       b1 = gen_prevlinkhdr_check(cstate);
+                       b0 = gen_ehostop(cstate, ebroadcast, Q_DST);
                        if (b1 != NULL)
                                gen_and(b1, b0);
                        return b0;
                case DLT_FDDI:
-                       return gen_fhostop(ebroadcast, Q_DST);
+                       return gen_fhostop(cstate, ebroadcast, Q_DST);
                case DLT_IEEE802:
-                       return gen_thostop(ebroadcast, Q_DST);
+                       return gen_thostop(cstate, ebroadcast, Q_DST);
                case DLT_IEEE802_11:
                case DLT_PRISM_HEADER:
                case DLT_IEEE802_11_RADIO_AVS:
                case DLT_IEEE802_11_RADIO:
                case DLT_PPI:
-                       return gen_wlanhostop(ebroadcast, Q_DST);
+                       return gen_wlanhostop(cstate, ebroadcast, Q_DST);
                case DLT_IP_OVER_FC:
-                       return gen_ipfchostop(ebroadcast, Q_DST);
+                       return gen_ipfchostop(cstate, ebroadcast, Q_DST);
                default:
-                       bpf_error("not a broadcast link");
+                       bpf_error(cstate, "not a broadcast link");
                }
                break;
 
@@ -7329,18 +7259,18 @@ gen_broadcast(proto)
                 * as an indication that we don't know the netmask, and fail
                 * in that case.
                 */
-               if (netmask == PCAP_NETMASK_UNKNOWN)
-                       bpf_error("netmask not known, so 'ip broadcast' not supported");
-               b0 = gen_linktype(ETHERTYPE_IP);
-               hostmask = ~netmask;
-               b1 = gen_mcmp(OR_LINKPL, 16, BPF_W, (bpf_int32)0, hostmask);
-               b2 = gen_mcmp(OR_LINKPL, 16, BPF_W,
+               if (cstate->netmask == PCAP_NETMASK_UNKNOWN)
+                       bpf_error(cstate, "netmask not known, so 'ip broadcast' not supported");
+               b0 = gen_linktype(cstate, ETHERTYPE_IP);
+               hostmask = ~cstate->netmask;
+               b1 = gen_mcmp(cstate, OR_LINKPL, 16, BPF_W, (bpf_int32)0, hostmask);
+               b2 = gen_mcmp(cstate, OR_LINKPL, 16, BPF_W,
                              (bpf_int32)(~0 & hostmask), hostmask);
                gen_or(b1, b2);
                gen_and(b0, b2);
                return b2;
        }
-       bpf_error("only link-layer/IP broadcast filters supported");
+       bpf_error(cstate, "only link-layer/IP broadcast filters supported");
        /* NOTREACHED */
        return NULL;
 }
@@ -7350,23 +7280,21 @@ gen_broadcast(proto)
  * the bottom bit of the *first* byte).
  */
 static struct block *
-gen_mac_multicast(offset)
-       int offset;
+gen_mac_multicast(compiler_state_t *cstate, int offset)
 {
        register struct block *b0;
        register struct slist *s;
 
        /* link[offset] & 1 != 0 */
-       s = gen_load_a(OR_LINKHDR, offset, BPF_B);
-       b0 = new_block(JMP(BPF_JSET));
+       s = gen_load_a(cstate, OR_LINKHDR, offset, BPF_B);
+       b0 = new_block(cstate, JMP(BPF_JSET));
        b0->s.k = 1;
        b0->stmts = s;
        return b0;
 }
 
 struct block *
-gen_multicast(proto)
-       int proto;
+gen_multicast(compiler_state_t *cstate, int proto)
 {
        register struct block *b0, *b1, *b2;
        register struct slist *s;
@@ -7375,17 +7303,17 @@ gen_multicast(proto)
 
        case Q_DEFAULT:
        case Q_LINK:
-               switch (linktype) {
+               switch (cstate->linktype) {
                case DLT_ARCNET:
                case DLT_ARCNET_LINUX:
                        /* all ARCnet multicasts use the same address */
-                       return gen_ahostop(abroadcast, Q_DST);
+                       return gen_ahostop(cstate, abroadcast, Q_DST);
                case DLT_EN10MB:
                case DLT_NETANALYZER:
                case DLT_NETANALYZER_TRANSPARENT:
-                       b1 = gen_prevlinkhdr_check();
+                       b1 = gen_prevlinkhdr_check(cstate);
                        /* ether[0] & 1 != 0 */
-                       b0 = gen_mac_multicast(0);
+                       b0 = gen_mac_multicast(cstate, 0);
                        if (b1 != NULL)
                                gen_and(b1, b0);
                        return b0;
@@ -7396,10 +7324,10 @@ gen_multicast(proto)
                         * XXX - was that referring to bit-order issues?
                         */
                        /* fddi[1] & 1 != 0 */
-                       return gen_mac_multicast(1);
+                       return gen_mac_multicast(cstate, 1);
                case DLT_IEEE802:
                        /* tr[2] & 1 != 0 */
-                       return gen_mac_multicast(2);
+                       return gen_mac_multicast(cstate, 2);
                case DLT_IEEE802_11:
                case DLT_PRISM_HEADER:
                case DLT_IEEE802_11_RADIO_AVS:
@@ -7426,23 +7354,23 @@ gen_multicast(proto)
                         *
                         * First, check for To DS set, i.e. "link[1] & 0x01".
                         */
-                       s = gen_load_a(OR_LINKHDR, 1, BPF_B);
-                       b1 = new_block(JMP(BPF_JSET));
+                       s = gen_load_a(cstate, OR_LINKHDR, 1, BPF_B);
+                       b1 = new_block(cstate, JMP(BPF_JSET));
                        b1->s.k = 0x01; /* To DS */
                        b1->stmts = s;
 
                        /*
                         * If To DS is set, the DA is at 16.
                         */
-                       b0 = gen_mac_multicast(16);
+                       b0 = gen_mac_multicast(cstate, 16);
                        gen_and(b1, b0);
 
                        /*
                         * Now, check for To DS not set, i.e. check
                         * "!(link[1] & 0x01)".
                         */
-                       s = gen_load_a(OR_LINKHDR, 1, BPF_B);
-                       b2 = new_block(JMP(BPF_JSET));
+                       s = gen_load_a(cstate, OR_LINKHDR, 1, BPF_B);
+                       b2 = new_block(cstate, JMP(BPF_JSET));
                        b2->s.k = 0x01; /* To DS */
                        b2->stmts = s;
                        gen_not(b2);
@@ -7450,7 +7378,7 @@ gen_multicast(proto)
                        /*
                         * If To DS is not set, the DA is at 4.
                         */
-                       b1 = gen_mac_multicast(4);
+                       b1 = gen_mac_multicast(cstate, 4);
                        gen_and(b2, b1);
 
                        /*
@@ -7463,8 +7391,8 @@ gen_multicast(proto)
                         * Now check for a data frame.
                         * I.e, check "link[0] & 0x08".
                         */
-                       s = gen_load_a(OR_LINKHDR, 0, BPF_B);
-                       b1 = new_block(JMP(BPF_JSET));
+                       s = gen_load_a(cstate, OR_LINKHDR, 0, BPF_B);
+                       b1 = new_block(cstate, JMP(BPF_JSET));
                        b1->s.k = 0x08;
                        b1->stmts = s;
 
@@ -7478,8 +7406,8 @@ gen_multicast(proto)
                         * is a management frame.
                         * I.e, check "!(link[0] & 0x08)".
                         */
-                       s = gen_load_a(OR_LINKHDR, 0, BPF_B);
-                       b2 = new_block(JMP(BPF_JSET));
+                       s = gen_load_a(cstate, OR_LINKHDR, 0, BPF_B);
+                       b2 = new_block(cstate, JMP(BPF_JSET));
                        b2->s.k = 0x08;
                        b2->stmts = s;
                        gen_not(b2);
@@ -7487,7 +7415,7 @@ gen_multicast(proto)
                        /*
                         * For management frames, the DA is at 4.
                         */
-                       b1 = gen_mac_multicast(4);
+                       b1 = gen_mac_multicast(cstate, 4);
                        gen_and(b2, b1);
 
                        /*
@@ -7505,8 +7433,8 @@ gen_multicast(proto)
                         *
                         * I.e., check "!(link[0] & 0x04)".
                         */
-                       s = gen_load_a(OR_LINKHDR, 0, BPF_B);
-                       b1 = new_block(JMP(BPF_JSET));
+                       s = gen_load_a(cstate, OR_LINKHDR, 0, BPF_B);
+                       b1 = new_block(cstate, JMP(BPF_JSET));
                        b1->s.k = 0x04;
                        b1->stmts = s;
                        gen_not(b1);
@@ -7518,7 +7446,7 @@ gen_multicast(proto)
                        gen_and(b1, b0);
                        return b0;
                case DLT_IP_OVER_FC:
-                       b0 = gen_mac_multicast(2);
+                       b0 = gen_mac_multicast(cstate, 2);
                        return b0;
                default:
                        break;
@@ -7527,18 +7455,18 @@ gen_multicast(proto)
                break;
 
        case Q_IP:
-               b0 = gen_linktype(ETHERTYPE_IP);
-               b1 = gen_cmp_ge(OR_LINKPL, 16, BPF_B, (bpf_int32)224);
+               b0 = gen_linktype(cstate, ETHERTYPE_IP);
+               b1 = gen_cmp_ge(cstate, OR_LINKPL, 16, BPF_B, (bpf_int32)224);
                gen_and(b0, b1);
                return b1;
 
        case Q_IPV6:
-               b0 = gen_linktype(ETHERTYPE_IPV6);
-               b1 = gen_cmp(OR_LINKPL, 24, BPF_B, (bpf_int32)255);
+               b0 = gen_linktype(cstate, ETHERTYPE_IPV6);
+               b1 = gen_cmp(cstate, OR_LINKPL, 24, BPF_B, (bpf_int32)255);
                gen_and(b0, b1);
                return b1;
        }
-       bpf_error("link-layer multicast filters supported only on ethernet/FDDI/token ring/ARCNET/802.11/ATM LANE/Fibre Channel");
+       bpf_error(cstate, "link-layer multicast filters supported only on ethernet/FDDI/token ring/ARCNET/802.11/ATM LANE/Fibre Channel");
        /* NOTREACHED */
        return NULL;
 }
@@ -7553,35 +7481,34 @@ gen_multicast(proto)
  * better accomplished using a higher-layer filter.
  */
 struct block *
-gen_inbound(dir)
-       int dir;
+gen_inbound(compiler_state_t *cstate, int dir)
 {
        register struct block *b0;
 
        /*
         * Only some data link types support inbound/outbound qualifiers.
         */
-       switch (linktype) {
+       switch (cstate->linktype) {
        case DLT_SLIP:
-               b0 = gen_relation(BPF_JEQ,
-                         gen_load(Q_LINK, gen_loadi(0), 1),
-                         gen_loadi(0),
+               b0 = gen_relation(cstate, BPF_JEQ,
+                         gen_load(cstate, Q_LINK, gen_loadi(cstate, 0), 1),
+                         gen_loadi(cstate, 0),
                          dir);
                break;
 
        case DLT_IPNET:
                if (dir) {
                        /* match outgoing packets */
-                       b0 = gen_cmp(OR_LINKHDR, 2, BPF_H, IPNET_OUTBOUND);
+                       b0 = gen_cmp(cstate, OR_LINKHDR, 2, BPF_H, IPNET_OUTBOUND);
                } else {
                        /* match incoming packets */
-                       b0 = gen_cmp(OR_LINKHDR, 2, BPF_H, IPNET_INBOUND);
+                       b0 = gen_cmp(cstate, OR_LINKHDR, 2, BPF_H, IPNET_INBOUND);
                }
                break;
 
        case DLT_LINUX_SLL:
                /* match outgoing packets */
-               b0 = gen_cmp(OR_LINKHDR, 0, BPF_H, LINUX_SLL_OUTGOING);
+               b0 = gen_cmp(cstate, OR_LINKHDR, 0, BPF_H, LINUX_SLL_OUTGOING);
                if (!dir) {
                        /* to filter on inbound traffic, invert the match */
                        gen_not(b0);
@@ -7590,7 +7517,7 @@ gen_inbound(dir)
 
 #ifdef HAVE_NET_PFVAR_H
        case DLT_PFLOG:
-               b0 = gen_cmp(OR_LINKHDR, offsetof(struct pfloghdr, dir), BPF_B,
+               b0 = gen_cmp(cstate, OR_LINKHDR, offsetof(struct pfloghdr, dir), BPF_B,
                    (bpf_int32)((dir == 0) ? PF_IN : PF_OUT));
                break;
 #endif
@@ -7598,10 +7525,10 @@ gen_inbound(dir)
        case DLT_PPP_PPPD:
                if (dir) {
                        /* match outgoing packets */
-                       b0 = gen_cmp(OR_LINKHDR, 0, BPF_B, PPP_PPPD_OUT);
+                       b0 = gen_cmp(cstate, OR_LINKHDR, 0, BPF_B, PPP_PPPD_OUT);
                } else {
                        /* match incoming packets */
-                       b0 = gen_cmp(OR_LINKHDR, 0, BPF_B, PPP_PPPD_IN);
+                       b0 = gen_cmp(cstate, OR_LINKHDR, 0, BPF_B, PPP_PPPD_IN);
                }
                break;
 
@@ -7632,10 +7559,10 @@ gen_inbound(dir)
                 * the byte after the 3-byte magic number */
                if (dir) {
                        /* match outgoing packets */
-                       b0 = gen_mcmp(OR_LINKHDR, 3, BPF_B, 0, 0x01);
+                       b0 = gen_mcmp(cstate, OR_LINKHDR, 3, BPF_B, 0, 0x01);
                } else {
                        /* match incoming packets */
-                       b0 = gen_mcmp(OR_LINKHDR, 3, BPF_B, 1, 0x01);
+                       b0 = gen_mcmp(cstate, OR_LINKHDR, 3, BPF_B, 1, 0x01);
                }
                break;
 
@@ -7652,23 +7579,23 @@ gen_inbound(dir)
                 * special meta-data in the filter expression;
                 * if it's a savefile, we can't.
                 */
-               if (bpf_pcap->rfile != NULL) {
+               if (cstate->bpf_pcap->rfile != NULL) {
                        /* We have a FILE *, so this is a savefile */
-                       bpf_error("inbound/outbound not supported on linktype %d when reading savefiles",
-                           linktype);
+                       bpf_error(cstate, "inbound/outbound not supported on linktype %d when reading savefiles",
+                           cstate->linktype);
                        b0 = NULL;
                        /* NOTREACHED */
                }
                /* match outgoing packets */
-               b0 = gen_cmp(OR_LINKHDR, SKF_AD_OFF + SKF_AD_PKTTYPE, BPF_H,
+               b0 = gen_cmp(cstate, OR_LINKHDR, SKF_AD_OFF + SKF_AD_PKTTYPE, BPF_H,
                             PACKET_OUTGOING);
                if (!dir) {
                        /* to filter on inbound traffic, invert the match */
                        gen_not(b0);
                }
 #else /* defined(linux) && defined(PF_PACKET) && defined(SO_ATTACH_FILTER) */
-               bpf_error("inbound/outbound not supported on linktype %d",
-                   linktype);
+               bpf_error(cstate, "inbound/outbound not supported on linktype %d",
+                   cstate->linktype);
                b0 = NULL;
                /* NOTREACHED */
 #endif /* defined(linux) && defined(PF_PACKET) && defined(SO_ATTACH_FILTER) */
@@ -7679,156 +7606,156 @@ gen_inbound(dir)
 #ifdef HAVE_NET_PFVAR_H
 /* PF firewall log matched interface */
 struct block *
-gen_pf_ifname(const char *ifname)
+gen_pf_ifname(compiler_state_t *cstate, const char *ifname)
 {
        struct block *b0;
        u_int len, off;
 
-       if (linktype != DLT_PFLOG) {
-               bpf_error("ifname supported only on PF linktype");
+       if (cstate->linktype != DLT_PFLOG) {
+               bpf_error(cstate, "ifname supported only on PF linktype");
                /* NOTREACHED */
        }
        len = sizeof(((struct pfloghdr *)0)->ifname);
        off = offsetof(struct pfloghdr, ifname);
        if (strlen(ifname) >= len) {
-               bpf_error("ifname interface names can only be %d characters",
+               bpf_error(cstate, "ifname interface names can only be %d characters",
                    len-1);
                /* NOTREACHED */
        }
-       b0 = gen_bcmp(OR_LINKHDR, off, strlen(ifname), (const u_char *)ifname);
+       b0 = gen_bcmp(cstate, OR_LINKHDR, off, strlen(ifname), (const u_char *)ifname);
        return (b0);
 }
 
 /* PF firewall log ruleset name */
 struct block *
-gen_pf_ruleset(char *ruleset)
+gen_pf_ruleset(compiler_state_t *cstate, char *ruleset)
 {
        struct block *b0;
 
-       if (linktype != DLT_PFLOG) {
-               bpf_error("ruleset supported only on PF linktype");
+       if (cstate->linktype != DLT_PFLOG) {
+               bpf_error(cstate, "ruleset supported only on PF linktype");
                /* NOTREACHED */
        }
 
        if (strlen(ruleset) >= sizeof(((struct pfloghdr *)0)->ruleset)) {
-               bpf_error("ruleset names can only be %ld characters",
+               bpf_error(cstate, "ruleset names can only be %ld characters",
                    (long)(sizeof(((struct pfloghdr *)0)->ruleset) - 1));
                /* NOTREACHED */
        }
 
-       b0 = gen_bcmp(OR_LINKHDR, offsetof(struct pfloghdr, ruleset),
+       b0 = gen_bcmp(cstate, OR_LINKHDR, offsetof(struct pfloghdr, ruleset),
            strlen(ruleset), (const u_char *)ruleset);
        return (b0);
 }
 
 /* PF firewall log rule number */
 struct block *
-gen_pf_rnr(int rnr)
+gen_pf_rnr(compiler_state_t *cstate, int rnr)
 {
        struct block *b0;
 
-       if (linktype != DLT_PFLOG) {
-               bpf_error("rnr supported only on PF linktype");
+       if (cstate->linktype != DLT_PFLOG) {
+               bpf_error(cstate, "rnr supported only on PF linktype");
                /* NOTREACHED */
        }
 
-       b0 = gen_cmp(OR_LINKHDR, offsetof(struct pfloghdr, rulenr), BPF_W,
+       b0 = gen_cmp(cstate, OR_LINKHDR, offsetof(struct pfloghdr, rulenr), BPF_W,
                 (bpf_int32)rnr);
        return (b0);
 }
 
 /* PF firewall log sub-rule number */
 struct block *
-gen_pf_srnr(int srnr)
+gen_pf_srnr(compiler_state_t *cstate, int srnr)
 {
        struct block *b0;
 
-       if (linktype != DLT_PFLOG) {
-               bpf_error("srnr supported only on PF linktype");
+       if (cstate->linktype != DLT_PFLOG) {
+               bpf_error(cstate, "srnr supported only on PF linktype");
                /* NOTREACHED */
        }
 
-       b0 = gen_cmp(OR_LINKHDR, offsetof(struct pfloghdr, subrulenr), BPF_W,
+       b0 = gen_cmp(cstate, OR_LINKHDR, offsetof(struct pfloghdr, subrulenr), BPF_W,
            (bpf_int32)srnr);
        return (b0);
 }
 
 /* PF firewall log reason code */
 struct block *
-gen_pf_reason(int reason)
+gen_pf_reason(compiler_state_t *cstate, int reason)
 {
        struct block *b0;
 
-       if (linktype != DLT_PFLOG) {
-               bpf_error("reason supported only on PF linktype");
+       if (cstate->linktype != DLT_PFLOG) {
+               bpf_error(cstate, "reason supported only on PF linktype");
                /* NOTREACHED */
        }
 
-       b0 = gen_cmp(OR_LINKHDR, offsetof(struct pfloghdr, reason), BPF_B,
+       b0 = gen_cmp(cstate, OR_LINKHDR, offsetof(struct pfloghdr, reason), BPF_B,
            (bpf_int32)reason);
        return (b0);
 }
 
 /* PF firewall log action */
 struct block *
-gen_pf_action(int action)
+gen_pf_action(compiler_state_t *cstate, int action)
 {
        struct block *b0;
 
-       if (linktype != DLT_PFLOG) {
-               bpf_error("action supported only on PF linktype");
+       if (cstate->linktype != DLT_PFLOG) {
+               bpf_error(cstate, "action supported only on PF linktype");
                /* NOTREACHED */
        }
 
-       b0 = gen_cmp(OR_LINKHDR, offsetof(struct pfloghdr, action), BPF_B,
+       b0 = gen_cmp(cstate, OR_LINKHDR, offsetof(struct pfloghdr, action), BPF_B,
            (bpf_int32)action);
        return (b0);
 }
 #else /* !HAVE_NET_PFVAR_H */
 struct block *
-gen_pf_ifname(const char *ifname)
+gen_pf_ifname(compiler_state_t *cstate, const char *ifname)
 {
-       bpf_error("libpcap was compiled without pf support");
+       bpf_error(cstate, "libpcap was compiled without pf support");
        /* NOTREACHED */
        return (NULL);
 }
 
 struct block *
-gen_pf_ruleset(char *ruleset)
+gen_pf_ruleset(compiler_state_t *cstate, char *ruleset)
 {
-       bpf_error("libpcap was compiled on a machine without pf support");
+       bpf_error(cstate, "libpcap was compiled on a machine without pf support");
        /* NOTREACHED */
        return (NULL);
 }
 
 struct block *
-gen_pf_rnr(int rnr)
+gen_pf_rnr(compiler_state_t *cstate, int rnr)
 {
-       bpf_error("libpcap was compiled on a machine without pf support");
+       bpf_error(cstate, "libpcap was compiled on a machine without pf support");
        /* NOTREACHED */
        return (NULL);
 }
 
 struct block *
-gen_pf_srnr(int srnr)
+gen_pf_srnr(compiler_state_t *cstate, int srnr)
 {
-       bpf_error("libpcap was compiled on a machine without pf support");
+       bpf_error(cstate, "libpcap was compiled on a machine without pf support");
        /* NOTREACHED */
        return (NULL);
 }
 
 struct block *
-gen_pf_reason(int reason)
+gen_pf_reason(compiler_state_t *cstate, int reason)
 {
-       bpf_error("libpcap was compiled on a machine without pf support");
+       bpf_error(cstate, "libpcap was compiled on a machine without pf support");
        /* NOTREACHED */
        return (NULL);
 }
 
 struct block *
-gen_pf_action(int action)
+gen_pf_action(compiler_state_t *cstate, int action)
 {
-       bpf_error("libpcap was compiled on a machine without pf support");
+       bpf_error(cstate, "libpcap was compiled on a machine without pf support");
        /* NOTREACHED */
        return (NULL);
 }
@@ -7836,22 +7763,22 @@ gen_pf_action(int action)
 
 /* IEEE 802.11 wireless header */
 struct block *
-gen_p80211_type(int type, int mask)
+gen_p80211_type(compiler_state_t *cstate, int type, int mask)
 {
        struct block *b0;
 
-       switch (linktype) {
+       switch (cstate->linktype) {
 
        case DLT_IEEE802_11:
        case DLT_PRISM_HEADER:
        case DLT_IEEE802_11_RADIO_AVS:
        case DLT_IEEE802_11_RADIO:
-               b0 = gen_mcmp(OR_LINKHDR, 0, BPF_B, (bpf_int32)type,
+               b0 = gen_mcmp(cstate, OR_LINKHDR, 0, BPF_B, (bpf_int32)type,
                    (bpf_int32)mask);
                break;
 
        default:
-               bpf_error("802.11 link-layer types supported only on 802.11");
+               bpf_error(cstate, "802.11 link-layer types supported only on 802.11");
                /* NOTREACHED */
        }
 
@@ -7859,11 +7786,11 @@ gen_p80211_type(int type, int mask)
 }
 
 struct block *
-gen_p80211_fcdir(int fcdir)
+gen_p80211_fcdir(compiler_state_t *cstate, int fcdir)
 {
        struct block *b0;
 
-       switch (linktype) {
+       switch (cstate->linktype) {
 
        case DLT_IEEE802_11:
        case DLT_PRISM_HEADER:
@@ -7872,93 +7799,89 @@ gen_p80211_fcdir(int fcdir)
                break;
 
        default:
-               bpf_error("frame direction supported only with 802.11 headers");
+               bpf_error(cstate, "frame direction supported only with 802.11 headers");
                /* NOTREACHED */
        }
 
-       b0 = gen_mcmp(OR_LINKHDR, 1, BPF_B, (bpf_int32)fcdir,
+       b0 = gen_mcmp(cstate, OR_LINKHDR, 1, BPF_B, (bpf_int32)fcdir,
                (bpf_u_int32)IEEE80211_FC1_DIR_MASK);
 
        return (b0);
 }
 
 struct block *
-gen_acode(eaddr, q)
-       register const u_char *eaddr;
-       struct qual q;
+gen_acode(compiler_state_t *cstate, const u_char *eaddr, struct qual q)
 {
-       switch (linktype) {
+       switch (cstate->linktype) {
 
        case DLT_ARCNET:
        case DLT_ARCNET_LINUX:
                if ((q.addr == Q_HOST || q.addr == Q_DEFAULT) &&
                    q.proto == Q_LINK)
-                       return (gen_ahostop(eaddr, (int)q.dir));
+                       return (gen_ahostop(cstate, eaddr, (int)q.dir));
                else {
-                       bpf_error("ARCnet address used in non-arc expression");
+                       bpf_error(cstate, "ARCnet address used in non-arc expression");
                        /* NOTREACHED */
                }
                break;
 
        default:
-               bpf_error("aid supported only on ARCnet");
+               bpf_error(cstate, "aid supported only on ARCnet");
                /* NOTREACHED */
        }
-       bpf_error("ARCnet address used in non-arc expression");
+       bpf_error(cstate, "ARCnet address used in non-arc expression");
        /* NOTREACHED */
        return NULL;
 }
 
 static struct block *
-gen_ahostop(eaddr, dir)
-       register const u_char *eaddr;
-       register int dir;
+gen_ahostop(compiler_state_t *cstate, const u_char *eaddr, int dir)
 {
        register struct block *b0, *b1;
 
        switch (dir) {
        /* src comes first, different from Ethernet */
        case Q_SRC:
-               return gen_bcmp(OR_LINKHDR, 0, 1, eaddr);
+               return gen_bcmp(cstate, OR_LINKHDR, 0, 1, eaddr);
 
        case Q_DST:
-               return gen_bcmp(OR_LINKHDR, 1, 1, eaddr);
+               return gen_bcmp(cstate, OR_LINKHDR, 1, 1, eaddr);
 
        case Q_AND:
-               b0 = gen_ahostop(eaddr, Q_SRC);
-               b1 = gen_ahostop(eaddr, Q_DST);
+               b0 = gen_ahostop(cstate, eaddr, Q_SRC);
+               b1 = gen_ahostop(cstate, eaddr, Q_DST);
                gen_and(b0, b1);
                return b1;
 
        case Q_DEFAULT:
        case Q_OR:
-               b0 = gen_ahostop(eaddr, Q_SRC);
-               b1 = gen_ahostop(eaddr, Q_DST);
+               b0 = gen_ahostop(cstate, eaddr, Q_SRC);
+               b1 = gen_ahostop(cstate, eaddr, Q_DST);
                gen_or(b0, b1);
                return b1;
 
        case Q_ADDR1:
-               bpf_error("'addr1' is only supported on 802.11");
+               bpf_error(cstate, "'addr1' is only supported on 802.11");
                break;
 
        case Q_ADDR2:
-               bpf_error("'addr2' is only supported on 802.11");
+               bpf_error(cstate, "'addr2' is only supported on 802.11");
                break;
 
        case Q_ADDR3:
-               bpf_error("'addr3' is only supported on 802.11");
+               bpf_error(cstate, "'addr3' is only supported on 802.11");
                break;
 
        case Q_ADDR4:
-               bpf_error("'addr4' is only supported on 802.11");
+               bpf_error(cstate, "'addr4' is only supported on 802.11");
                break;
 
        case Q_RA:
-               bpf_error("'ra' is only supported on 802.11");
+               bpf_error(cstate, "'ra' is only supported on 802.11");
                break;
 
        case Q_TA:
-               bpf_error("'ta' is only supported on 802.11");
+               bpf_error(cstate, "'ta' is only supported on 802.11");
                break;
        }
        abort();
@@ -7974,18 +7897,18 @@ gen_vlan_bpf_extensions(int vlan_num)
 
         /* generate new filter code based on extracting packet
          * metadata */
-        s = new_stmt(BPF_LD|BPF_B|BPF_ABS);
+        s = new_stmt(cstate, BPF_LD|BPF_B|BPF_ABS);
         s->s.k = SKF_AD_OFF + SKF_AD_VLAN_TAG_PRESENT;
 
-        b0 = new_block(JMP(BPF_JEQ));
+        b0 = new_block(cstate, JMP(BPF_JEQ));
         b0->stmts = s;
         b0->s.k = 1;
 
         if (vlan_num >= 0) {
-                s = new_stmt(BPF_LD|BPF_B|BPF_ABS);
+                s = new_stmt(cstate, BPF_LD|BPF_B|BPF_ABS);
                 s->s.k = SKF_AD_OFF + SKF_AD_VLAN_TAG;
 
-                b1 = new_block(JMP(BPF_JEQ));
+                b1 = new_block(cstate, JMP(BPF_JEQ));
                 b1->stmts = s;
                 b1->s.k = (bpf_int32) vlan_num;
 
@@ -7998,22 +7921,22 @@ gen_vlan_bpf_extensions(int vlan_num)
 #endif
 
 static struct block *
-gen_vlan_no_bpf_extensions(int vlan_num)
+gen_vlan_no_bpf_extensions(compiler_state_t *cstate, int vlan_num)
 {
         struct block *b0, *b1;
 
         /* check for VLAN, including QinQ */
-        b0 = gen_linktype(ETHERTYPE_8021Q);
-        b1 = gen_linktype(ETHERTYPE_8021AD);
+        b0 = gen_linktype(cstate, ETHERTYPE_8021Q);
+        b1 = gen_linktype(cstate, ETHERTYPE_8021AD);
         gen_or(b0,b1);
         b0 = b1;
-        b1 = gen_linktype(ETHERTYPE_8021QINQ);
+        b1 = gen_linktype(cstate, ETHERTYPE_8021QINQ);
         gen_or(b0,b1);
         b0 = b1;
 
         /* If a specific VLAN is requested, check VLAN id */
         if (vlan_num >= 0) {
-                b1 = gen_mcmp(OR_LINKPL, 0, BPF_H,
+                b1 = gen_mcmp(cstate, OR_LINKPL, 0, BPF_H,
                               (bpf_int32)vlan_num, 0x0fff);
                 gen_and(b0, b1);
                 b0 = b1;
@@ -8023,13 +7946,13 @@ gen_vlan_no_bpf_extensions(int vlan_num)
         * The payload follows the full header, including the
         * VLAN tags, so skip past this VLAN tag.
         */
-        off_linkpl.constant_part += 4;
+        cstate->off_linkpl.constant_part += 4;
 
        /*
         * The link-layer type information follows the VLAN tags, so
         * skip past this VLAN tag.
         */
-        off_linktype.constant_part += 4;
+        cstate->off_linktype.constant_part += 4;
 
         return b0;
 }
@@ -8038,14 +7961,13 @@ gen_vlan_no_bpf_extensions(int vlan_num)
  * support IEEE 802.1Q VLAN trunk over ethernet
  */
 struct block *
-gen_vlan(vlan_num)
-       int vlan_num;
+gen_vlan(compiler_state_t *cstate, int vlan_num)
 {
        struct  block   *b0;
 
        /* can't check for VLAN-encapsulated packets inside MPLS */
-       if (label_stack_depth > 0)
-               bpf_error("no VLAN match after MPLS");
+       if (cstate->label_stack_depth > 0)
+               bpf_error(cstate, "no VLAN match after MPLS");
 
        /*
         * Check for a VLAN packet, and then change the offsets to point
@@ -8078,7 +8000,7 @@ gen_vlan(vlan_num)
         * be done assuming a VLAN, even though the "or" could be viewed
         * as meaning "or, if this isn't a VLAN packet...".
         */
-       switch (linktype) {
+       switch (cstate->linktype) {
 
        case DLT_EN10MB:
        case DLT_NETANALYZER:
@@ -8086,35 +8008,35 @@ gen_vlan(vlan_num)
 #if defined(SKF_AD_VLAN_TAG) && defined(SKF_AD_VLAN_TAG_PRESENT)
                /* Verify that this is the outer part of the packet and
                 * not encapsulated somehow. */
-               if (vlan_stack_depth == 0 && !off_linkhdr.is_variable &&
-                   off_linkhdr.constant_part ==
+               if (cstate->vlan_stack_depth == 0 && !cstate->off_linkhdr.is_variable &&
+                   cstate->off_linkhdr.constant_part ==
                    off_outermostlinkhdr.constant_part) {
                        /*
                         * Do we need special VLAN handling?
                         */
-                       if (bpf_pcap->bpf_codegen_flags & BPF_SPECIAL_VLAN_HANDLING)
+                       if (cstate->bpf_pcap->bpf_codegen_flags & BPF_SPECIAL_VLAN_HANDLING)
                                b0 = gen_vlan_bpf_extensions(vlan_num);
                        else
-                               b0 = gen_vlan_no_bpf_extensions(vlan_num);
+                               b0 = gen_vlan_no_bpf_extensions(cstate, vlan_num);
                } else
 #endif
-                       b0 = gen_vlan_no_bpf_extensions(vlan_num);
+                       b0 = gen_vlan_no_bpf_extensions(cstate, vlan_num);
                 break;
 
        case DLT_IEEE802_11:
        case DLT_PRISM_HEADER:
        case DLT_IEEE802_11_RADIO_AVS:
        case DLT_IEEE802_11_RADIO:
-               b0 = gen_vlan_no_bpf_extensions(vlan_num);
+               b0 = gen_vlan_no_bpf_extensions(cstate, vlan_num);
                break;
 
        default:
-               bpf_error("no VLAN support for data link type %d",
-                     linktype);
+               bpf_error(cstate, "no VLAN support for data link type %d",
+                     cstate->linktype);
                /*NOTREACHED*/
        }
 
-        vlan_stack_depth++;
+        cstate->vlan_stack_depth++;
 
        return (b0);
 }
@@ -8123,30 +8045,29 @@ gen_vlan(vlan_num)
  * support for MPLS
  */
 struct block *
-gen_mpls(label_num)
-       int label_num;
+gen_mpls(compiler_state_t *cstate, int label_num)
 {
        struct  block   *b0, *b1;
 
-        if (label_stack_depth > 0) {
+        if (cstate->label_stack_depth > 0) {
             /* just match the bottom-of-stack bit clear */
-            b0 = gen_mcmp(OR_PREVMPLSHDR, 2, BPF_B, 0, 0x01);
+            b0 = gen_mcmp(cstate, OR_PREVMPLSHDR, 2, BPF_B, 0, 0x01);
         } else {
             /*
              * We're not in an MPLS stack yet, so check the link-layer
              * type against MPLS.
              */
-            switch (linktype) {
+            switch (cstate->linktype) {
 
             case DLT_C_HDLC: /* fall through */
             case DLT_EN10MB:
             case DLT_NETANALYZER:
             case DLT_NETANALYZER_TRANSPARENT:
-                    b0 = gen_linktype(ETHERTYPE_MPLS);
+                    b0 = gen_linktype(cstate, ETHERTYPE_MPLS);
                     break;
 
             case DLT_PPP:
-                    b0 = gen_linktype(PPP_MPLS_UCAST);
+                    b0 = gen_linktype(cstate, PPP_MPLS_UCAST);
                     break;
 
                     /* FIXME add other DLT_s ...
@@ -8154,8 +8075,8 @@ gen_mpls(label_num)
                      * leave it for now */
 
             default:
-                    bpf_error("no MPLS support for data link type %d",
-                          linktype);
+                    bpf_error(cstate, "no MPLS support for data link type %d",
+                          cstate->linktype);
                     b0 = NULL;
                     /*NOTREACHED*/
                     break;
@@ -8165,7 +8086,7 @@ gen_mpls(label_num)
        /* If a specific MPLS label is requested, check it */
        if (label_num >= 0) {
                label_num = label_num << 12; /* label is shifted 12 bits on the wire */
-               b1 = gen_mcmp(OR_LINKPL, 0, BPF_W, (bpf_int32)label_num,
+               b1 = gen_mcmp(cstate, OR_LINKPL, 0, BPF_W, (bpf_int32)label_num,
                    0xfffff000); /* only compare the first 20 bits */
                gen_and(b0, b1);
                b0 = b1;
@@ -8185,9 +8106,9 @@ gen_mpls(label_num)
          *
          * XXX - this is a bit of a kludge.  See comments in gen_vlan().
          */
-        off_nl_nosnap += 4;
-        off_nl += 4;
-        label_stack_depth++;
+        cstate->off_nl_nosnap += 4;
+        cstate->off_nl += 4;
+        cstate->label_stack_depth++;
        return (b0);
 }
 
@@ -8195,26 +8116,25 @@ gen_mpls(label_num)
  * Support PPPOE discovery and session.
  */
 struct block *
-gen_pppoed()
+gen_pppoed(compiler_state_t *cstate)
 {
        /* check for PPPoE discovery */
-       return gen_linktype((bpf_int32)ETHERTYPE_PPPOED);
+       return gen_linktype(cstate, (bpf_int32)ETHERTYPE_PPPOED);
 }
 
 struct block *
-gen_pppoes(sess_num)
-       int sess_num;
+gen_pppoes(compiler_state_t *cstate, int sess_num)
 {
        struct block *b0, *b1;
 
        /*
         * Test against the PPPoE session link-layer type.
         */
-       b0 = gen_linktype((bpf_int32)ETHERTYPE_PPPOES);
+       b0 = gen_linktype(cstate, (bpf_int32)ETHERTYPE_PPPOES);
 
        /* If a specific session is requested, check PPPoE session id */
        if (sess_num >= 0) {
-               b1 = gen_mcmp(OR_LINKPL, 0, BPF_W,
+               b1 = gen_mcmp(cstate, OR_LINKPL, 0, BPF_W,
                    (bpf_int32)sess_num, 0x0000ffff);
                gen_and(b0, b1);
                b0 = b1;
@@ -8257,17 +8177,17 @@ gen_pppoes(sess_num)
         * starts at the first byte of the PPP packet.  For PPPoE,
         * that offset is relative to the beginning of the total
         * link-layer payload, including any 802.2 LLC header, so
-        * it's 6 bytes past off_nl.
+        * it's 6 bytes past cstate->off_nl.
         */
-       PUSH_LINKHDR(DLT_PPP, off_linkpl.is_variable,
-           off_linkpl.constant_part + off_nl + 6, /* 6 bytes past the PPPoE header */
-           off_linkpl.reg);
+       PUSH_LINKHDR(cstate, DLT_PPP, cstate->off_linkpl.is_variable,
+           cstate->off_linkpl.constant_part + cstate->off_nl + 6, /* 6 bytes past the PPPoE header */
+           cstate->off_linkpl.reg);
 
-       off_linktype = off_linkhdr;
-       off_linkpl.constant_part = off_linkhdr.constant_part + 2;
+       cstate->off_linktype = cstate->off_linkhdr;
+       cstate->off_linkpl.constant_part = cstate->off_linkhdr.constant_part + 2;
 
-       off_nl = 0;
-       off_nl_nosnap = 0;      /* no 802.2 LLC */
+       cstate->off_nl = 0;
+       cstate->off_nl_nosnap = 0;      /* no 802.2 LLC */
 
        return b0;
 }
@@ -8275,23 +8195,24 @@ gen_pppoes(sess_num)
 /* Check that this is Geneve and the VNI is correct if
  * specified. Parameterized to handle both IPv4 and IPv6. */
 static struct block *
-gen_geneve_check(struct block *(*gen_portfn)(int, int, int),
-                enum e_offrel offrel, int vni)
+gen_geneve_check(compiler_state_t *cstate,
+    struct block *(*gen_portfn)(compiler_state_t *, int, int, int),
+    enum e_offrel offrel, int vni)
 {
        struct block *b0, *b1;
 
-       b0 = gen_portfn(GENEVE_PORT, IPPROTO_UDP, Q_DST);
+       b0 = gen_portfn(cstate, GENEVE_PORT, IPPROTO_UDP, Q_DST);
 
        /* Check that we are operating on version 0. Otherwise, we
         * can't decode the rest of the fields. The version is 2 bits
         * in the first byte of the Geneve header. */
-       b1 = gen_mcmp(offrel, 8, BPF_B, (bpf_int32)0, 0xc0);
+       b1 = gen_mcmp(cstate, offrel, 8, BPF_B, (bpf_int32)0, 0xc0);
        gen_and(b0, b1);
        b0 = b1;
 
        if (vni >= 0) {
                vni <<= 8; /* VNI is in the upper 3 bytes */
-               b1 = gen_mcmp(offrel, 12, BPF_W, (bpf_int32)vni,
+               b1 = gen_mcmp(cstate, offrel, 12, BPF_W, (bpf_int32)vni,
                              0xffffff00);
                gen_and(b0, b1);
                b0 = b1;
@@ -8306,23 +8227,23 @@ gen_geneve_check(struct block *(*gen_portfn)(int, int, int),
  *   needed) into register A to be used later to compute
  *   the inner packet offsets. */
 static struct block *
-gen_geneve4(int vni)
+gen_geneve4(compiler_state_t *cstate, int vni)
 {
        struct block *b0, *b1;
        struct slist *s, *s1;
 
-       b0 = gen_geneve_check(gen_port, OR_TRAN_IPV4, vni);
+       b0 = gen_geneve_check(cstate, gen_port, OR_TRAN_IPV4, vni);
 
        /* Load the IP header length into A. */
-       s = gen_loadx_iphdrlen();
+       s = gen_loadx_iphdrlen(cstate);
 
-       s1 = new_stmt(BPF_MISC|BPF_TXA);
+       s1 = new_stmt(cstate, BPF_MISC|BPF_TXA);
        sappend(s, s1);
 
        /* Forcibly append these statements to the true condition
         * of the protocol check by creating a new block that is
         * always true and ANDing them. */
-       b1 = new_block(BPF_JMP|BPF_JEQ|BPF_X);
+       b1 = new_block(cstate, BPF_JMP|BPF_JEQ|BPF_X);
        b1->stmts = s;
        b1->s.k = 0;
 
@@ -8332,36 +8253,36 @@ gen_geneve4(int vni)
 }
 
 static struct block *
-gen_geneve6(int vni)
+gen_geneve6(compiler_state_t *cstate, int vni)
 {
        struct block *b0, *b1;
        struct slist *s, *s1;
 
-       b0 = gen_geneve_check(gen_port6, OR_TRAN_IPV6, vni);
+       b0 = gen_geneve_check(cstate, gen_port6, OR_TRAN_IPV6, vni);
 
        /* Load the IP header length. We need to account for a
         * variable length link prefix if there is one. */
-       s = gen_abs_offset_varpart(&off_linkpl);
+       s = gen_abs_offset_varpart(cstate, &cstate->off_linkpl);
        if (s) {
-               s1 = new_stmt(BPF_LD|BPF_IMM);
+               s1 = new_stmt(cstate, BPF_LD|BPF_IMM);
                s1->s.k = 40;
                sappend(s, s1);
 
-               s1 = new_stmt(BPF_ALU|BPF_ADD|BPF_X);
+               s1 = new_stmt(cstate, BPF_ALU|BPF_ADD|BPF_X);
                s1->s.k = 0;
                sappend(s, s1);
        } else {
-               s = new_stmt(BPF_LD|BPF_IMM);
+               s = new_stmt(cstate, BPF_LD|BPF_IMM);
                s->s.k = 40;
        }
 
        /* Forcibly append these statements to the true condition
         * of the protocol check by creating a new block that is
         * always true and ANDing them. */
-       s1 = new_stmt(BPF_MISC|BPF_TAX);
+       s1 = new_stmt(cstate, BPF_MISC|BPF_TAX);
        sappend(s, s1);
 
-       b1 = new_block(BPF_JMP|BPF_JEQ|BPF_X);
+       b1 = new_block(cstate, BPF_JMP|BPF_JEQ|BPF_X);
        b1->stmts = s;
        b1->s.k = 0;
 
@@ -8375,7 +8296,7 @@ gen_geneve6(int vni)
  * - The offset of the end of the Geneve header.
  * - The offset of the end of the encapsulated MAC header. */
 static struct slist *
-gen_geneve_offsets(void)
+gen_geneve_offsets(compiler_state_t *cstate)
 {
        struct slist *s, *s1, *s_proto;
 
@@ -8384,49 +8305,49 @@ gen_geneve_offsets(void)
         * (include any variable link prefix) and stored in A plus the
         * fixed sized headers (fixed link prefix, MAC length, and UDP
         * header). */
-       s = new_stmt(BPF_ALU|BPF_ADD|BPF_K);
-       s->s.k = off_linkpl.constant_part + off_nl + 8;
+       s = new_stmt(cstate, BPF_ALU|BPF_ADD|BPF_K);
+       s->s.k = cstate->off_linkpl.constant_part + cstate->off_nl + 8;
 
        /* Stash this in X since we'll need it later. */
-       s1 = new_stmt(BPF_MISC|BPF_TAX);
+       s1 = new_stmt(cstate, BPF_MISC|BPF_TAX);
        sappend(s, s1);
 
        /* The EtherType in Geneve is 2 bytes in. Calculate this and
         * store it. */
-       s1 = new_stmt(BPF_ALU|BPF_ADD|BPF_K);
+       s1 = new_stmt(cstate, BPF_ALU|BPF_ADD|BPF_K);
        s1->s.k = 2;
        sappend(s, s1);
 
-       off_linktype.reg = alloc_reg();
-       off_linktype.is_variable = 1;
-       off_linktype.constant_part = 0;
+       cstate->off_linktype.reg = alloc_reg(cstate);
+       cstate->off_linktype.is_variable = 1;
+       cstate->off_linktype.constant_part = 0;
 
-       s1 = new_stmt(BPF_ST);
-       s1->s.k = off_linktype.reg;
+       s1 = new_stmt(cstate, BPF_ST);
+       s1->s.k = cstate->off_linktype.reg;
        sappend(s, s1);
 
        /* Load the Geneve option length and mask and shift to get the
         * number of bytes. It is stored in the first byte of the Geneve
         * header. */
-       s1 = new_stmt(BPF_LD|BPF_IND|BPF_B);
+       s1 = new_stmt(cstate, BPF_LD|BPF_IND|BPF_B);
        s1->s.k = 0;
        sappend(s, s1);
 
-       s1 = new_stmt(BPF_ALU|BPF_AND|BPF_K);
+       s1 = new_stmt(cstate, BPF_ALU|BPF_AND|BPF_K);
        s1->s.k = 0x3f;
        sappend(s, s1);
 
-       s1 = new_stmt(BPF_ALU|BPF_MUL|BPF_K);
+       s1 = new_stmt(cstate, BPF_ALU|BPF_MUL|BPF_K);
        s1->s.k = 4;
        sappend(s, s1);
 
        /* Add in the rest of the Geneve base header. */
-       s1 = new_stmt(BPF_ALU|BPF_ADD|BPF_K);
+       s1 = new_stmt(cstate, BPF_ALU|BPF_ADD|BPF_K);
        s1->s.k = 8;
        sappend(s, s1);
 
        /* Add the Geneve header length to its offset and store. */
-       s1 = new_stmt(BPF_ALU|BPF_ADD|BPF_X);
+       s1 = new_stmt(cstate, BPF_ALU|BPF_ADD|BPF_X);
        s1->s.k = 0;
        sappend(s, s1);
 
@@ -8438,10 +8359,10 @@ gen_geneve_offsets(void)
         * - The only link layer that we have specific support for is
         *   Ethernet. We will confirm that the packet actually is
         *   Ethernet at runtime before executing these checks. */
-       PUSH_LINKHDR(DLT_EN10MB, 1, 0, alloc_reg());
+       PUSH_LINKHDR(cstate, DLT_EN10MB, 1, 0, alloc_reg(cstate));
 
-       s1 = new_stmt(BPF_ST);
-       s1->s.k = off_linkhdr.reg;
+       s1 = new_stmt(cstate, BPF_ST);
+       s1->s.k = cstate->off_linkhdr.reg;
        sappend(s, s1);
 
        /* Calculate whether we have an Ethernet header or just raw IP/
@@ -8450,73 +8371,73 @@ gen_geneve_offsets(void)
         * seamlessly. Otherwise, keep what we've calculated already. */
 
        /* We have a bare jmp so we can't use the optimizer. */
-       no_optimize = 1;
+       cstate->no_optimize = 1;
 
        /* Load the EtherType in the Geneve header, 2 bytes in. */
-       s1 = new_stmt(BPF_LD|BPF_IND|BPF_H);
+       s1 = new_stmt(cstate, BPF_LD|BPF_IND|BPF_H);
        s1->s.k = 2;
        sappend(s, s1);
 
        /* Load X with the end of the Geneve header. */
-       s1 = new_stmt(BPF_LDX|BPF_MEM);
-       s1->s.k = off_linkhdr.reg;
+       s1 = new_stmt(cstate, BPF_LDX|BPF_MEM);
+       s1->s.k = cstate->off_linkhdr.reg;
        sappend(s, s1);
 
        /* Check if the EtherType is Transparent Ethernet Bridging. At the
         * end of this check, we should have the total length in X. In
         * the non-Ethernet case, it's already there. */
-       s_proto = new_stmt(JMP(BPF_JEQ));
+       s_proto = new_stmt(cstate, JMP(BPF_JEQ));
        s_proto->s.k = ETHERTYPE_TEB;
        sappend(s, s_proto);
 
-       s1 = new_stmt(BPF_MISC|BPF_TXA);
+       s1 = new_stmt(cstate, BPF_MISC|BPF_TXA);
        sappend(s, s1);
        s_proto->s.jt = s1;
 
        /* Since this is Ethernet, use the EtherType of the payload
         * directly as the linktype. Overwrite what we already have. */
-       s1 = new_stmt(BPF_ALU|BPF_ADD|BPF_K);
+       s1 = new_stmt(cstate, BPF_ALU|BPF_ADD|BPF_K);
        s1->s.k = 12;
        sappend(s, s1);
 
-       s1 = new_stmt(BPF_ST);
-       s1->s.k = off_linktype.reg;
+       s1 = new_stmt(cstate, BPF_ST);
+       s1->s.k = cstate->off_linktype.reg;
        sappend(s, s1);
 
        /* Advance two bytes further to get the end of the Ethernet
         * header. */
-       s1 = new_stmt(BPF_ALU|BPF_ADD|BPF_K);
+       s1 = new_stmt(cstate, BPF_ALU|BPF_ADD|BPF_K);
        s1->s.k = 2;
        sappend(s, s1);
 
        /* Move the result to X. */
-       s1 = new_stmt(BPF_MISC|BPF_TAX);
+       s1 = new_stmt(cstate, BPF_MISC|BPF_TAX);
        sappend(s, s1);
 
        /* Store the final result of our linkpl calculation. */
-       off_linkpl.reg = alloc_reg();
-       off_linkpl.is_variable = 1;
-       off_linkpl.constant_part = 0;
+       cstate->off_linkpl.reg = alloc_reg(cstate);
+       cstate->off_linkpl.is_variable = 1;
+       cstate->off_linkpl.constant_part = 0;
 
-       s1 = new_stmt(BPF_STX);
-       s1->s.k = off_linkpl.reg;
+       s1 = new_stmt(cstate, BPF_STX);
+       s1->s.k = cstate->off_linkpl.reg;
        sappend(s, s1);
        s_proto->s.jf = s1;
 
-       off_nl = 0;
+       cstate->off_nl = 0;
 
        return s;
 }
 
 /* Check to see if this is a Geneve packet. */
 struct block *
-gen_geneve(int vni)
+gen_geneve(compiler_state_t *cstate, int vni)
 {
        struct block *b0, *b1;
        struct slist *s;
 
-       b0 = gen_geneve4(vni);
-       b1 = gen_geneve6(vni);
+       b0 = gen_geneve4(cstate, vni);
+       b1 = gen_geneve6(cstate, vni);
 
        gen_or(b0, b1);
        b0 = b1;
@@ -8524,15 +8445,15 @@ gen_geneve(int vni)
        /* Later filters should act on the payload of the Geneve frame,
         * update all of the header pointers. Attach this code so that
         * it gets executed in the event that the Geneve filter matches. */
-       s = gen_geneve_offsets();
+       s = gen_geneve_offsets(cstate);
 
-       b1 = gen_true();
+       b1 = gen_true(cstate);
        sappend(s, b1->stmts);
        b1->stmts = s;
 
        gen_and(b0, b1);
 
-       is_geneve = 1;
+       cstate->is_geneve = 1;
 
        return b1;
 }
@@ -8540,7 +8461,7 @@ gen_geneve(int vni)
 /* Check that the encapsulated frame has a link layer header
  * for Ethernet filters. */
 static struct block *
-gen_geneve_ll_check()
+gen_geneve_ll_check(compiler_state_t *cstate)
 {
        struct block *b0;
        struct slist *s, *s1;
@@ -8551,14 +8472,14 @@ gen_geneve_ll_check()
 
        /* Geneve always generates pure variable offsets so we can
         * compare only the registers. */
-       s = new_stmt(BPF_LD|BPF_MEM);
-       s->s.k = off_linkhdr.reg;
+       s = new_stmt(cstate, BPF_LD|BPF_MEM);
+       s->s.k = cstate->off_linkhdr.reg;
 
-       s1 = new_stmt(BPF_LDX|BPF_MEM);
-       s1->s.k = off_linkpl.reg;
+       s1 = new_stmt(cstate, BPF_LDX|BPF_MEM);
+       s1->s.k = cstate->off_linkpl.reg;
        sappend(s, s1);
 
-       b0 = new_block(BPF_JMP|BPF_JEQ|BPF_X);
+       b0 = new_block(cstate, BPF_JMP|BPF_JEQ|BPF_X);
        b0->stmts = s;
        b0->s.k = 0;
        gen_not(b0);
@@ -8567,54 +8488,51 @@ gen_geneve_ll_check()
 }
 
 struct block *
-gen_atmfield_code(atmfield, jvalue, jtype, reverse)
-       int atmfield;
-       bpf_int32 jvalue;
-       bpf_u_int32 jtype;
-       int reverse;
+gen_atmfield_code(compiler_state_t *cstate, int atmfield, bpf_int32 jvalue,
+    bpf_u_int32 jtype, int reverse)
 {
        struct block *b0;
 
        switch (atmfield) {
 
        case A_VPI:
-               if (!is_atm)
-                       bpf_error("'vpi' supported only on raw ATM");
-               if (off_vpi == (u_int)-1)
+               if (!cstate->is_atm)
+                       bpf_error(cstate, "'vpi' supported only on raw ATM");
+               if (cstate->off_vpi == (u_int)-1)
                        abort();
-               b0 = gen_ncmp(OR_LINKHDR, off_vpi, BPF_B, 0xffffffff, jtype,
+               b0 = gen_ncmp(cstate, OR_LINKHDR, cstate->off_vpi, BPF_B, 0xffffffff, jtype,
                    reverse, jvalue);
                break;
 
        case A_VCI:
-               if (!is_atm)
-                       bpf_error("'vci' supported only on raw ATM");
-               if (off_vci == (u_int)-1)
+               if (!cstate->is_atm)
+                       bpf_error(cstate, "'vci' supported only on raw ATM");
+               if (cstate->off_vci == (u_int)-1)
                        abort();
-               b0 = gen_ncmp(OR_LINKHDR, off_vci, BPF_H, 0xffffffff, jtype,
+               b0 = gen_ncmp(cstate, OR_LINKHDR, cstate->off_vci, BPF_H, 0xffffffff, jtype,
                    reverse, jvalue);
                break;
 
        case A_PROTOTYPE:
-               if (off_proto == (u_int)-1)
+               if (cstate->off_proto == (u_int)-1)
                        abort();        /* XXX - this isn't on FreeBSD */
-               b0 = gen_ncmp(OR_LINKHDR, off_proto, BPF_B, 0x0f, jtype,
+               b0 = gen_ncmp(cstate, OR_LINKHDR, cstate->off_proto, BPF_B, 0x0f, jtype,
                    reverse, jvalue);
                break;
 
        case A_MSGTYPE:
-               if (off_payload == (u_int)-1)
+               if (cstate->off_payload == (u_int)-1)
                        abort();
-               b0 = gen_ncmp(OR_LINKHDR, off_payload + MSG_TYPE_POS, BPF_B,
+               b0 = gen_ncmp(cstate, OR_LINKHDR, cstate->off_payload + MSG_TYPE_POS, BPF_B,
                    0xffffffff, jtype, reverse, jvalue);
                break;
 
        case A_CALLREFTYPE:
-               if (!is_atm)
-                       bpf_error("'callref' supported only on raw ATM");
-               if (off_proto == (u_int)-1)
+               if (!cstate->is_atm)
+                       bpf_error(cstate, "'callref' supported only on raw ATM");
+               if (cstate->off_proto == (u_int)-1)
                        abort();
-               b0 = gen_ncmp(OR_LINKHDR, off_proto, BPF_B, 0xffffffff,
+               b0 = gen_ncmp(cstate, OR_LINKHDR, cstate->off_proto, BPF_B, 0xffffffff,
                    jtype, reverse, jvalue);
                break;
 
@@ -8625,8 +8543,7 @@ gen_atmfield_code(atmfield, jvalue, jtype, reverse)
 }
 
 struct block *
-gen_atmtype_abbrev(type)
-       int type;
+gen_atmtype_abbrev(compiler_state_t *cstate, int type)
 {
        struct block *b0, *b1;
 
@@ -8634,63 +8551,63 @@ gen_atmtype_abbrev(type)
 
        case A_METAC:
                /* Get all packets in Meta signalling Circuit */
-               if (!is_atm)
-                       bpf_error("'metac' supported only on raw ATM");
-               b0 = gen_atmfield_code(A_VPI, 0, BPF_JEQ, 0);
-               b1 = gen_atmfield_code(A_VCI, 1, BPF_JEQ, 0);
+               if (!cstate->is_atm)
+                       bpf_error(cstate, "'metac' supported only on raw ATM");
+               b0 = gen_atmfield_code(cstate, A_VPI, 0, BPF_JEQ, 0);
+               b1 = gen_atmfield_code(cstate, A_VCI, 1, BPF_JEQ, 0);
                gen_and(b0, b1);
                break;
 
        case A_BCC:
                /* Get all packets in Broadcast Circuit*/
-               if (!is_atm)
-                       bpf_error("'bcc' supported only on raw ATM");
-               b0 = gen_atmfield_code(A_VPI, 0, BPF_JEQ, 0);
-               b1 = gen_atmfield_code(A_VCI, 2, BPF_JEQ, 0);
+               if (!cstate->is_atm)
+                       bpf_error(cstate, "'bcc' supported only on raw ATM");
+               b0 = gen_atmfield_code(cstate, A_VPI, 0, BPF_JEQ, 0);
+               b1 = gen_atmfield_code(cstate, A_VCI, 2, BPF_JEQ, 0);
                gen_and(b0, b1);
                break;
 
        case A_OAMF4SC:
                /* Get all cells in Segment OAM F4 circuit*/
-               if (!is_atm)
-                       bpf_error("'oam4sc' supported only on raw ATM");
-               b0 = gen_atmfield_code(A_VPI, 0, BPF_JEQ, 0);
-               b1 = gen_atmfield_code(A_VCI, 3, BPF_JEQ, 0);
+               if (!cstate->is_atm)
+                       bpf_error(cstate, "'oam4sc' supported only on raw ATM");
+               b0 = gen_atmfield_code(cstate, A_VPI, 0, BPF_JEQ, 0);
+               b1 = gen_atmfield_code(cstate, A_VCI, 3, BPF_JEQ, 0);
                gen_and(b0, b1);
                break;
 
        case A_OAMF4EC:
                /* Get all cells in End-to-End OAM F4 Circuit*/
-               if (!is_atm)
-                       bpf_error("'oam4ec' supported only on raw ATM");
-               b0 = gen_atmfield_code(A_VPI, 0, BPF_JEQ, 0);
-               b1 = gen_atmfield_code(A_VCI, 4, BPF_JEQ, 0);
+               if (!cstate->is_atm)
+                       bpf_error(cstate, "'oam4ec' supported only on raw ATM");
+               b0 = gen_atmfield_code(cstate, A_VPI, 0, BPF_JEQ, 0);
+               b1 = gen_atmfield_code(cstate, A_VCI, 4, BPF_JEQ, 0);
                gen_and(b0, b1);
                break;
 
        case A_SC:
                /*  Get all packets in connection Signalling Circuit */
-               if (!is_atm)
-                       bpf_error("'sc' supported only on raw ATM");
-               b0 = gen_atmfield_code(A_VPI, 0, BPF_JEQ, 0);
-               b1 = gen_atmfield_code(A_VCI, 5, BPF_JEQ, 0);
+               if (!cstate->is_atm)
+                       bpf_error(cstate, "'sc' supported only on raw ATM");
+               b0 = gen_atmfield_code(cstate, A_VPI, 0, BPF_JEQ, 0);
+               b1 = gen_atmfield_code(cstate, A_VCI, 5, BPF_JEQ, 0);
                gen_and(b0, b1);
                break;
 
        case A_ILMIC:
                /* Get all packets in ILMI Circuit */
-               if (!is_atm)
-                       bpf_error("'ilmic' supported only on raw ATM");
-               b0 = gen_atmfield_code(A_VPI, 0, BPF_JEQ, 0);
-               b1 = gen_atmfield_code(A_VCI, 16, BPF_JEQ, 0);
+               if (!cstate->is_atm)
+                       bpf_error(cstate, "'ilmic' supported only on raw ATM");
+               b0 = gen_atmfield_code(cstate, A_VPI, 0, BPF_JEQ, 0);
+               b1 = gen_atmfield_code(cstate, A_VCI, 16, BPF_JEQ, 0);
                gen_and(b0, b1);
                break;
 
        case A_LANE:
                /* Get all LANE packets */
-               if (!is_atm)
-                       bpf_error("'lane' supported only on raw ATM");
-               b1 = gen_atmfield_code(A_PROTOTYPE, PT_LANE, BPF_JEQ, 0);
+               if (!cstate->is_atm)
+                       bpf_error(cstate, "'lane' supported only on raw ATM");
+               b1 = gen_atmfield_code(cstate, A_PROTOTYPE, PT_LANE, BPF_JEQ, 0);
 
                /*
                 * Arrange that all subsequent tests assume LANE
@@ -8700,21 +8617,21 @@ gen_atmtype_abbrev(type)
                 *
                 * We assume LANE means Ethernet, not Token Ring.
                 */
-               PUSH_LINKHDR(DLT_EN10MB, 0,
-                   off_payload + 2,    /* Ethernet header */
+               PUSH_LINKHDR(cstate, DLT_EN10MB, 0,
+                   cstate->off_payload + 2,    /* Ethernet header */
                    -1);
-               off_linktype.constant_part = off_linkhdr.constant_part + 12;
-               off_linkpl.constant_part = off_linkhdr.constant_part + 14;      /* Ethernet */
-               off_nl = 0;                     /* Ethernet II */
-               off_nl_nosnap = 3;              /* 802.3+802.2 */
+               cstate->off_linktype.constant_part = cstate->off_linkhdr.constant_part + 12;
+               cstate->off_linkpl.constant_part = cstate->off_linkhdr.constant_part + 14;      /* Ethernet */
+               cstate->off_nl = 0;                     /* Ethernet II */
+               cstate->off_nl_nosnap = 3;              /* 802.3+802.2 */
                break;
 
        case A_LLC:
                /* Get all LLC-encapsulated packets */
-               if (!is_atm)
-                       bpf_error("'llc' supported only on raw ATM");
-               b1 = gen_atmfield_code(A_PROTOTYPE, PT_LLC, BPF_JEQ, 0);
-               linktype = prevlinktype;
+               if (!cstate->is_atm)
+                       bpf_error(cstate, "'llc' supported only on raw ATM");
+               b1 = gen_atmfield_code(cstate, A_PROTOTYPE, PT_LLC, BPF_JEQ, 0);
+               cstate->linktype = cstate->prevlinktype;
                break;
 
        default:
@@ -8731,65 +8648,64 @@ gen_atmtype_abbrev(type)
  * For MTP2_HSL, sequences are on 2 bytes, and length on 9 bits
  */
 struct block *
-gen_mtp2type_abbrev(type)
-       int type;
+gen_mtp2type_abbrev(compiler_state_t *cstate, int type)
 {
        struct block *b0, *b1;
 
        switch (type) {
 
        case M_FISU:
-               if ( (linktype != DLT_MTP2) &&
-                    (linktype != DLT_ERF) &&
-                    (linktype != DLT_MTP2_WITH_PHDR) )
-                       bpf_error("'fisu' supported only on MTP2");
-               /* gen_ncmp(offrel, offset, size, mask, jtype, reverse, value) */
-               b0 = gen_ncmp(OR_PACKET, off_li, BPF_B, 0x3f, BPF_JEQ, 0, 0);
+               if ( (cstate->linktype != DLT_MTP2) &&
+                    (cstate->linktype != DLT_ERF) &&
+                    (cstate->linktype != DLT_MTP2_WITH_PHDR) )
+                       bpf_error(cstate, "'fisu' supported only on MTP2");
+               /* gen_ncmp(cstate, offrel, offset, size, mask, jtype, reverse, value) */
+               b0 = gen_ncmp(cstate, OR_PACKET, cstate->off_li, BPF_B, 0x3f, BPF_JEQ, 0, 0);
                break;
 
        case M_LSSU:
-               if ( (linktype != DLT_MTP2) &&
-                    (linktype != DLT_ERF) &&
-                    (linktype != DLT_MTP2_WITH_PHDR) )
-                       bpf_error("'lssu' supported only on MTP2");
-               b0 = gen_ncmp(OR_PACKET, off_li, BPF_B, 0x3f, BPF_JGT, 1, 2);
-               b1 = gen_ncmp(OR_PACKET, off_li, BPF_B, 0x3f, BPF_JGT, 0, 0);
+               if ( (cstate->linktype != DLT_MTP2) &&
+                    (cstate->linktype != DLT_ERF) &&
+                    (cstate->linktype != DLT_MTP2_WITH_PHDR) )
+                       bpf_error(cstate, "'lssu' supported only on MTP2");
+               b0 = gen_ncmp(cstate, OR_PACKET, cstate->off_li, BPF_B, 0x3f, BPF_JGT, 1, 2);
+               b1 = gen_ncmp(cstate, OR_PACKET, cstate->off_li, BPF_B, 0x3f, BPF_JGT, 0, 0);
                gen_and(b1, b0);
                break;
 
        case M_MSU:
-               if ( (linktype != DLT_MTP2) &&
-                    (linktype != DLT_ERF) &&
-                    (linktype != DLT_MTP2_WITH_PHDR) )
-                       bpf_error("'msu' supported only on MTP2");
-               b0 = gen_ncmp(OR_PACKET, off_li, BPF_B, 0x3f, BPF_JGT, 0, 2);
+               if ( (cstate->linktype != DLT_MTP2) &&
+                    (cstate->linktype != DLT_ERF) &&
+                    (cstate->linktype != DLT_MTP2_WITH_PHDR) )
+                       bpf_error(cstate, "'msu' supported only on MTP2");
+               b0 = gen_ncmp(cstate, OR_PACKET, cstate->off_li, BPF_B, 0x3f, BPF_JGT, 0, 2);
                break;
 
        case MH_FISU:
-               if ( (linktype != DLT_MTP2) &&
-                    (linktype != DLT_ERF) &&
-                    (linktype != DLT_MTP2_WITH_PHDR) )
-                       bpf_error("'hfisu' supported only on MTP2_HSL");
-               /* gen_ncmp(offrel, offset, size, mask, jtype, reverse, value) */
-               b0 = gen_ncmp(OR_PACKET, off_li_hsl, BPF_H, 0xff80, BPF_JEQ, 0, 0);
+               if ( (cstate->linktype != DLT_MTP2) &&
+                    (cstate->linktype != DLT_ERF) &&
+                    (cstate->linktype != DLT_MTP2_WITH_PHDR) )
+                       bpf_error(cstate, "'hfisu' supported only on MTP2_HSL");
+               /* gen_ncmp(cstate, offrel, offset, size, mask, jtype, reverse, value) */
+               b0 = gen_ncmp(cstate, OR_PACKET, cstate->off_li_hsl, BPF_H, 0xff80, BPF_JEQ, 0, 0);
                break;
 
        case MH_LSSU:
-               if ( (linktype != DLT_MTP2) &&
-                    (linktype != DLT_ERF) &&
-                    (linktype != DLT_MTP2_WITH_PHDR) )
-                       bpf_error("'hlssu' supported only on MTP2_HSL");
-               b0 = gen_ncmp(OR_PACKET, off_li_hsl, BPF_H, 0xff80, BPF_JGT, 1, 0x0100);
-               b1 = gen_ncmp(OR_PACKET, off_li_hsl, BPF_H, 0xff80, BPF_JGT, 0, 0);
+               if ( (cstate->linktype != DLT_MTP2) &&
+                    (cstate->linktype != DLT_ERF) &&
+                    (cstate->linktype != DLT_MTP2_WITH_PHDR) )
+                       bpf_error(cstate, "'hlssu' supported only on MTP2_HSL");
+               b0 = gen_ncmp(cstate, OR_PACKET, cstate->off_li_hsl, BPF_H, 0xff80, BPF_JGT, 1, 0x0100);
+               b1 = gen_ncmp(cstate, OR_PACKET, cstate->off_li_hsl, BPF_H, 0xff80, BPF_JGT, 0, 0);
                gen_and(b1, b0);
                break;
 
        case MH_MSU:
-               if ( (linktype != DLT_MTP2) &&
-                    (linktype != DLT_ERF) &&
-                    (linktype != DLT_MTP2_WITH_PHDR) )
-                       bpf_error("'hmsu' supported only on MTP2_HSL");
-               b0 = gen_ncmp(OR_PACKET, off_li_hsl, BPF_H, 0xff80, BPF_JGT, 0, 0x0100);
+               if ( (cstate->linktype != DLT_MTP2) &&
+                    (cstate->linktype != DLT_ERF) &&
+                    (cstate->linktype != DLT_MTP2_WITH_PHDR) )
+                       bpf_error(cstate, "'hmsu' supported only on MTP2_HSL");
+               b0 = gen_ncmp(cstate, OR_PACKET, cstate->off_li_hsl, BPF_H, 0xff80, BPF_JGT, 0, 0x0100);
                break;
 
        default:
@@ -8799,18 +8715,15 @@ gen_mtp2type_abbrev(type)
 }
 
 struct block *
-gen_mtp3field_code(mtp3field, jvalue, jtype, reverse)
-       int mtp3field;
-       bpf_u_int32 jvalue;
-       bpf_u_int32 jtype;
-       int reverse;
+gen_mtp3field_code(compiler_state_t *cstate, int mtp3field, bpf_u_int32 jvalue,
+    bpf_u_int32 jtype, int reverse)
 {
        struct block *b0;
        bpf_u_int32 val1 , val2 , val3;
-       u_int newoff_sio=off_sio;
-       u_int newoff_opc=off_opc;
-       u_int newoff_dpc=off_dpc;
-       u_int newoff_sls=off_sls;
+       u_int newoff_sio = cstate->off_sio;
+       u_int newoff_opc = cstate->off_opc;
+       u_int newoff_dpc = cstate->off_dpc;
+       u_int newoff_sls = cstate->off_sls;
 
        switch (mtp3field) {
 
@@ -8819,24 +8732,24 @@ gen_mtp3field_code(mtp3field, jvalue, jtype, reverse)
                /* FALLTHROUGH */
 
        case M_SIO:
-               if (off_sio == (u_int)-1)
-                       bpf_error("'sio' supported only on SS7");
+               if (cstate->off_sio == (u_int)-1)
+                       bpf_error(cstate, "'sio' supported only on SS7");
                /* sio coded on 1 byte so max value 255 */
                if(jvalue > 255)
-                       bpf_error("sio value %u too big; max value = 255",
+                       bpf_error(cstate, "sio value %u too big; max value = 255",
                            jvalue);
-               b0 = gen_ncmp(OR_PACKET, newoff_sio, BPF_B, 0xffffffff,
+               b0 = gen_ncmp(cstate, OR_PACKET, newoff_sio, BPF_B, 0xffffffff,
                    (u_int)jtype, reverse, (u_int)jvalue);
                break;
 
        case MH_OPC:
                newoff_opc+=3;
         case M_OPC:
-               if (off_opc == (u_int)-1)
-                       bpf_error("'opc' supported only on SS7");
+               if (cstate->off_opc == (u_int)-1)
+                       bpf_error(cstate, "'opc' supported only on SS7");
                /* opc coded on 14 bits so max value 16383 */
                if (jvalue > 16383)
-                       bpf_error("opc value %u too big; max value = 16383",
+                       bpf_error(cstate, "opc value %u too big; max value = 16383",
                            jvalue);
                /* the following instructions are made to convert jvalue
                 * to the form used to write opc in an ss7 message*/
@@ -8847,7 +8760,7 @@ gen_mtp3field_code(mtp3field, jvalue, jtype, reverse)
                val3 = jvalue & 0x00000003;
                val3 = val3 <<22;
                jvalue = val1 + val2 + val3;
-               b0 = gen_ncmp(OR_PACKET, newoff_opc, BPF_W, 0x00c0ff0f,
+               b0 = gen_ncmp(cstate, OR_PACKET, newoff_opc, BPF_W, 0x00c0ff0f,
                    (u_int)jtype, reverse, (u_int)jvalue);
                break;
 
@@ -8856,11 +8769,11 @@ gen_mtp3field_code(mtp3field, jvalue, jtype, reverse)
                /* FALLTHROUGH */
 
        case M_DPC:
-               if (off_dpc == (u_int)-1)
-                       bpf_error("'dpc' supported only on SS7");
+               if (cstate->off_dpc == (u_int)-1)
+                       bpf_error(cstate, "'dpc' supported only on SS7");
                /* dpc coded on 14 bits so max value 16383 */
                if (jvalue > 16383)
-                       bpf_error("dpc value %u too big; max value = 16383",
+                       bpf_error(cstate, "dpc value %u too big; max value = 16383",
                            jvalue);
                /* the following instructions are made to convert jvalue
                 * to the forme used to write dpc in an ss7 message*/
@@ -8869,23 +8782,23 @@ gen_mtp3field_code(mtp3field, jvalue, jtype, reverse)
                val2 = jvalue & 0x00003f00;
                val2 = val2 << 8;
                jvalue = val1 + val2;
-               b0 = gen_ncmp(OR_PACKET, newoff_dpc, BPF_W, 0xff3f0000,
+               b0 = gen_ncmp(cstate, OR_PACKET, newoff_dpc, BPF_W, 0xff3f0000,
                    (u_int)jtype, reverse, (u_int)jvalue);
                break;
 
        case MH_SLS:
          newoff_sls+=3;
        case M_SLS:
-               if (off_sls == (u_int)-1)
-                       bpf_error("'sls' supported only on SS7");
+               if (cstate->off_sls == (u_int)-1)
+                       bpf_error(cstate, "'sls' supported only on SS7");
                /* sls coded on 4 bits so max value 15 */
                if (jvalue > 15)
-                        bpf_error("sls value %u too big; max value = 15",
+                        bpf_error(cstate, "sls value %u too big; max value = 15",
                             jvalue);
                /* the following instruction is made to convert jvalue
                 * to the forme used to write sls in an ss7 message*/
                jvalue = jvalue << 4;
-               b0 = gen_ncmp(OR_PACKET, newoff_sls, BPF_B, 0xf0,
+               b0 = gen_ncmp(cstate, OR_PACKET, newoff_sls, BPF_B, 0xf0,
                    (u_int)jtype,reverse, (u_int)jvalue);
                break;
 
@@ -8896,8 +8809,7 @@ gen_mtp3field_code(mtp3field, jvalue, jtype, reverse)
 }
 
 static struct block *
-gen_msg_abbrev(type)
-       int type;
+gen_msg_abbrev(compiler_state_t *cstate, int type)
 {
        struct block *b1;
 
@@ -8908,27 +8820,27 @@ gen_msg_abbrev(type)
        switch (type) {
 
        case A_SETUP:
-               b1 = gen_atmfield_code(A_MSGTYPE, SETUP, BPF_JEQ, 0);
+               b1 = gen_atmfield_code(cstate, A_MSGTYPE, SETUP, BPF_JEQ, 0);
                break;
 
        case A_CALLPROCEED:
-               b1 = gen_atmfield_code(A_MSGTYPE, CALL_PROCEED, BPF_JEQ, 0);
+               b1 = gen_atmfield_code(cstate, A_MSGTYPE, CALL_PROCEED, BPF_JEQ, 0);
                break;
 
        case A_CONNECT:
-               b1 = gen_atmfield_code(A_MSGTYPE, CONNECT, BPF_JEQ, 0);
+               b1 = gen_atmfield_code(cstate, A_MSGTYPE, CONNECT, BPF_JEQ, 0);
                break;
 
        case A_CONNECTACK:
-               b1 = gen_atmfield_code(A_MSGTYPE, CONNECT_ACK, BPF_JEQ, 0);
+               b1 = gen_atmfield_code(cstate, A_MSGTYPE, CONNECT_ACK, BPF_JEQ, 0);
                break;
 
        case A_RELEASE:
-               b1 = gen_atmfield_code(A_MSGTYPE, RELEASE, BPF_JEQ, 0);
+               b1 = gen_atmfield_code(cstate, A_MSGTYPE, RELEASE, BPF_JEQ, 0);
                break;
 
        case A_RELEASE_DONE:
-               b1 = gen_atmfield_code(A_MSGTYPE, RELEASE_DONE, BPF_JEQ, 0);
+               b1 = gen_atmfield_code(cstate, A_MSGTYPE, RELEASE_DONE, BPF_JEQ, 0);
                break;
 
        default:
@@ -8938,27 +8850,26 @@ gen_msg_abbrev(type)
 }
 
 struct block *
-gen_atmmulti_abbrev(type)
-       int type;
+gen_atmmulti_abbrev(compiler_state_t *cstate, int type)
 {
        struct block *b0, *b1;
 
        switch (type) {
 
        case A_OAM:
-               if (!is_atm)
-                       bpf_error("'oam' supported only on raw ATM");
-               b1 = gen_atmmulti_abbrev(A_OAMF4);
+               if (!cstate->is_atm)
+                       bpf_error(cstate, "'oam' supported only on raw ATM");
+               b1 = gen_atmmulti_abbrev(cstate, A_OAMF4);
                break;
 
        case A_OAMF4:
-               if (!is_atm)
-                       bpf_error("'oamf4' supported only on raw ATM");
+               if (!cstate->is_atm)
+                       bpf_error(cstate, "'oamf4' supported only on raw ATM");
                /* OAM F4 type */
-               b0 = gen_atmfield_code(A_VCI, 3, BPF_JEQ, 0);
-               b1 = gen_atmfield_code(A_VCI, 4, BPF_JEQ, 0);
+               b0 = gen_atmfield_code(cstate, A_VCI, 3, BPF_JEQ, 0);
+               b1 = gen_atmfield_code(cstate, A_VCI, 4, BPF_JEQ, 0);
                gen_or(b0, b1);
-               b0 = gen_atmfield_code(A_VPI, 0, BPF_JEQ, 0);
+               b0 = gen_atmfield_code(cstate, A_VPI, 0, BPF_JEQ, 0);
                gen_and(b0, b1);
                break;
 
@@ -8967,36 +8878,36 @@ gen_atmmulti_abbrev(type)
                 * Get Q.2931 signalling messages for switched
                 * virtual connection
                 */
-               if (!is_atm)
-                       bpf_error("'connectmsg' supported only on raw ATM");
-               b0 = gen_msg_abbrev(A_SETUP);
-               b1 = gen_msg_abbrev(A_CALLPROCEED);
+               if (!cstate->is_atm)
+                       bpf_error(cstate, "'connectmsg' supported only on raw ATM");
+               b0 = gen_msg_abbrev(cstate, A_SETUP);
+               b1 = gen_msg_abbrev(cstate, A_CALLPROCEED);
                gen_or(b0, b1);
-               b0 = gen_msg_abbrev(A_CONNECT);
+               b0 = gen_msg_abbrev(cstate, A_CONNECT);
                gen_or(b0, b1);
-               b0 = gen_msg_abbrev(A_CONNECTACK);
+               b0 = gen_msg_abbrev(cstate, A_CONNECTACK);
                gen_or(b0, b1);
-               b0 = gen_msg_abbrev(A_RELEASE);
+               b0 = gen_msg_abbrev(cstate, A_RELEASE);
                gen_or(b0, b1);
-               b0 = gen_msg_abbrev(A_RELEASE_DONE);
+               b0 = gen_msg_abbrev(cstate, A_RELEASE_DONE);
                gen_or(b0, b1);
-               b0 = gen_atmtype_abbrev(A_SC);
+               b0 = gen_atmtype_abbrev(cstate, A_SC);
                gen_and(b0, b1);
                break;
 
        case A_METACONNECT:
-               if (!is_atm)
-                       bpf_error("'metaconnect' supported only on raw ATM");
-               b0 = gen_msg_abbrev(A_SETUP);
-               b1 = gen_msg_abbrev(A_CALLPROCEED);
+               if (!cstate->is_atm)
+                       bpf_error(cstate, "'metaconnect' supported only on raw ATM");
+               b0 = gen_msg_abbrev(cstate, A_SETUP);
+               b1 = gen_msg_abbrev(cstate, A_CALLPROCEED);
                gen_or(b0, b1);
-               b0 = gen_msg_abbrev(A_CONNECT);
+               b0 = gen_msg_abbrev(cstate, A_CONNECT);
                gen_or(b0, b1);
-               b0 = gen_msg_abbrev(A_RELEASE);
+               b0 = gen_msg_abbrev(cstate, A_RELEASE);
                gen_or(b0, b1);
-               b0 = gen_msg_abbrev(A_RELEASE_DONE);
+               b0 = gen_msg_abbrev(cstate, A_RELEASE_DONE);
                gen_or(b0, b1);
-               b0 = gen_atmtype_abbrev(A_METAC);
+               b0 = gen_atmtype_abbrev(cstate, A_METAC);
                gen_and(b0, b1);
                break;
 
index 76c612413a0a77e76c8d5fd919c85bb607b1c4d4..2b089d21d561689cbabd4d165906a54e08f2863a 100644 (file)
--- a/gencode.h
+++ b/gencode.h
@@ -281,88 +281,115 @@ struct qual {
        unsigned char pad;
 };
 
-struct arth *gen_loadi(int);
-struct arth *gen_load(int, struct arth *, int);
-struct arth *gen_loadlen(void);
-struct arth *gen_neg(struct arth *);
-struct arth *gen_arth(int, struct arth *, struct arth *);
+struct _compiler_state;
+
+typedef struct _compiler_state compiler_state_t;
+
+struct arth *gen_loadi(compiler_state_t *, int);
+struct arth *gen_load(compiler_state_t *, int, struct arth *, int);
+struct arth *gen_loadlen(compiler_state_t *);
+struct arth *gen_neg(compiler_state_t *, struct arth *);
+struct arth *gen_arth(compiler_state_t *, int, struct arth *, struct arth *);
 
 void gen_and(struct block *, struct block *);
 void gen_or(struct block *, struct block *);
 void gen_not(struct block *);
 
-struct block *gen_scode(const char *, struct qual);
-struct block *gen_ecode(const u_char *, struct qual);
-struct block *gen_acode(const u_char *, struct qual);
-struct block *gen_mcode(const char *, const char *, unsigned int, struct qual);
+struct block *gen_scode(compiler_state_t *, const char *, struct qual);
+struct block *gen_ecode(compiler_state_t *, const u_char *, struct qual);
+struct block *gen_acode(compiler_state_t *, const u_char *, struct qual);
+struct block *gen_mcode(compiler_state_t *, const char *, const char *,
+    unsigned int, struct qual);
 #ifdef INET6
-struct block *gen_mcode6(const char *, const char *, unsigned int, struct qual);
+struct block *gen_mcode6(compiler_state_t *, const char *, const char *,
+    unsigned int, struct qual);
 #endif
-struct block *gen_ncode(const char *, bpf_u_int32, struct qual);
-struct block *gen_proto_abbrev(int);
-struct block *gen_relation(int, struct arth *, struct arth *, int);
-struct block *gen_less(int);
-struct block *gen_greater(int);
-struct block *gen_byteop(int, int, int);
-struct block *gen_broadcast(int);
-struct block *gen_multicast(int);
-struct block *gen_inbound(int);
-
-struct block *gen_llc(void);
-struct block *gen_llc_i(void);
-struct block *gen_llc_s(void);
-struct block *gen_llc_u(void);
-struct block *gen_llc_s_subtype(bpf_u_int32);
-struct block *gen_llc_u_subtype(bpf_u_int32);
-
-struct block *gen_vlan(int);
-struct block *gen_mpls(int);
-
-struct block *gen_pppoed(void);
-struct block *gen_pppoes(int);
-
-struct block *gen_geneve(int);
-
-struct block *gen_atmfield_code(int atmfield, bpf_int32 jvalue, bpf_u_int32 jtype, int reverse);
-struct block *gen_atmtype_abbrev(int type);
-struct block *gen_atmmulti_abbrev(int type);
-
-struct block *gen_mtp2type_abbrev(int type);
-struct block *gen_mtp3field_code(int mtp3field, bpf_u_int32 jvalue, bpf_u_int32 jtype, int reverse);
-
-struct block *gen_pf_ifname(const char *);
-struct block *gen_pf_rnr(int);
-struct block *gen_pf_srnr(int);
-struct block *gen_pf_ruleset(char *);
-struct block *gen_pf_reason(int);
-struct block *gen_pf_action(int);
-struct block *gen_pf_dir(int);
-
-struct block *gen_p80211_type(int, int);
-struct block *gen_p80211_fcdir(int);
-
-void bpf_optimize(struct block **);
-void bpf_error(const char *, ...)
+struct block *gen_ncode(compiler_state_t *, const char *, bpf_u_int32,
+    struct qual);
+struct block *gen_proto_abbrev(compiler_state_t *, int);
+struct block *gen_relation(compiler_state_t *, int, struct arth *,
+    struct arth *, int);
+struct block *gen_less(compiler_state_t *, int);
+struct block *gen_greater(compiler_state_t *, int);
+struct block *gen_byteop(compiler_state_t *, int, int, int);
+struct block *gen_broadcast(compiler_state_t *, int);
+struct block *gen_multicast(compiler_state_t *, int);
+struct block *gen_inbound(compiler_state_t *, int);
+
+struct block *gen_llc(compiler_state_t *);
+struct block *gen_llc_i(compiler_state_t *);
+struct block *gen_llc_s(compiler_state_t *);
+struct block *gen_llc_u(compiler_state_t *);
+struct block *gen_llc_s_subtype(compiler_state_t *, bpf_u_int32);
+struct block *gen_llc_u_subtype(compiler_state_t *, bpf_u_int32);
+
+struct block *gen_vlan(compiler_state_t *, int);
+struct block *gen_mpls(compiler_state_t *, int);
+
+struct block *gen_pppoed(compiler_state_t *);
+struct block *gen_pppoes(compiler_state_t *, int);
+
+struct block *gen_geneve(compiler_state_t *, int);
+
+struct block *gen_atmfield_code(compiler_state_t *, int, bpf_int32,
+    bpf_u_int32, int);
+struct block *gen_atmtype_abbrev(compiler_state_t *, int type);
+struct block *gen_atmmulti_abbrev(compiler_state_t *, int type);
+
+struct block *gen_mtp2type_abbrev(compiler_state_t *, int type);
+struct block *gen_mtp3field_code(compiler_state_t *, int, bpf_u_int32,
+    bpf_u_int32, int);
+
+struct block *gen_pf_ifname(compiler_state_t *, const char *);
+struct block *gen_pf_rnr(compiler_state_t *, int);
+struct block *gen_pf_srnr(compiler_state_t *, int);
+struct block *gen_pf_ruleset(compiler_state_t *, char *);
+struct block *gen_pf_reason(compiler_state_t *, int);
+struct block *gen_pf_action(compiler_state_t *, int);
+
+struct block *gen_p80211_type(compiler_state_t *, int, int);
+struct block *gen_p80211_fcdir(compiler_state_t *, int);
+
+/*
+ * Representation of a program as a tree of blocks, plus current mark.
+ * A block is marked if only if its mark equals the current mark.
+ * Rather than traverse the code array, marking each item, 'cur_mark'
+ * is incremented.  This automatically makes each element unmarked.
+ */
+#define isMarked(icp, p) ((p)->mark == (icp)->cur_mark)
+#define unMarkAll(icp) (icp)->cur_mark += 1
+#define Mark(icp, p) ((p)->mark = (icp)->cur_mark)
+
+struct icode {
+       struct block *root;
+       int cur_mark;
+};
+
+void bpf_optimize(compiler_state_t *, struct icode *ic);
+void bpf_syntax_error(compiler_state_t *, const char *);
+void bpf_error(compiler_state_t *, const char *, ...)
     __attribute__((noreturn))
 #ifdef __ATTRIBUTE___FORMAT_OK
-    __attribute__((format (printf, 1, 2)))
+    __attribute__((format (printf, 2, 3)))
 #endif /* __ATTRIBUTE___FORMAT_OK */
     ;
 
-void finish_parse(struct block *);
-char *sdup(const char *);
+void finish_parse(compiler_state_t *, struct block *);
+char *sdup(compiler_state_t *, const char *);
 
-struct bpf_insn *icode_to_fcode(struct block *, u_int *);
+struct _opt_state;
+typedef struct _opt_state opt_state_t;
+
+struct bpf_insn *icode_to_fcode(compiler_state_t *, struct icode *,
+    struct block *, u_int *);
 void sappend(struct slist *, struct slist *);
 
 /*
  * Older versions of Bison don't put this declaration in
  * grammar.h.
  */
-int pcap_parse(void *);
+int pcap_parse(void *, compiler_state_t *);
 
 /* XXX */
 #define JT(b)  ((b)->et.succ)
 #define JF(b)  ((b)->ef.succ)
-
-extern int no_optimize;
index 5af2972c1976adf7946ce82549ab103eceb7e121..a1460f524480708e79349770fdca5ca5596e15ca 100644 (file)
--- a/grammar.y
+++ b/grammar.y
 %parse-param   {void *yyscanner}
 %lex-param   {void *yyscanner}
 
+/*
+ * And we need to pass the compiler state to the scanner.
+ */
+%parse-param {compiler_state_t *cstate}
+
 %{
 /*
  * Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996
@@ -192,21 +197,18 @@ str2tok(const char *str, const struct tok *toks)
        return (-1);
 }
 
-int n_errors = 0;
-
 static struct qual qerr = { Q_UNDEF, Q_UNDEF, Q_UNDEF, Q_UNDEF };
 
 static void
-yyerror(void *yyscanner, const char *msg)
+yyerror(void *yyscanner, compiler_state_t *cstate, const char *msg)
 {
-       ++n_errors;
-       bpf_error("%s", msg);
+       bpf_syntax_error(cstate, msg);
        /* NOTREACHED */
 }
 
 #ifdef HAVE_NET_PFVAR_H
 static int
-pfreason_to_num(const char *reason)
+pfreason_to_num(compiler_state_t *cstate, const char *reason)
 {
        const char *reasons[] = PFRES_NAMES;
        int i;
@@ -215,12 +217,12 @@ pfreason_to_num(const char *reason)
                if (pcap_strcasecmp(reason, reasons[i]) == 0)
                        return (i);
        }
-       bpf_error("unknown PF reason");
+       bpf_error(cstate, "unknown PF reason");
        /*NOTREACHED*/
 }
 
 static int
-pfaction_to_num(const char *action)
+pfaction_to_num(compiler_state_t *cstate, const char *action)
 {
        if (pcap_strcasecmp(action, "pass") == 0 ||
            pcap_strcasecmp(action, "accept") == 0)
@@ -239,15 +241,15 @@ pfaction_to_num(const char *action)
                return (PF_NORDR);
 #endif
        else {
-               bpf_error("unknown PF action");
+               bpf_error(cstate, "unknown PF action");
                /*NOTREACHED*/
        }
 }
 #else /* !HAVE_NET_PFVAR_H */
 static int
-pfreason_to_num(const char *reason)
+pfreason_to_num(compiler_state_t *cstate, const char *reason)
 {
-       bpf_error("libpcap was compiled on a machine without pf support");
+       bpf_error(cstate, "libpcap was compiled on a machine without pf support");
        /*NOTREACHED*/
 
        /* this is to make the VC compiler happy */
@@ -255,9 +257,9 @@ pfreason_to_num(const char *reason)
 }
 
 static int
-pfaction_to_num(const char *action)
+pfaction_to_num(compiler_state_t *cstate, const char *action)
 {
-       bpf_error("libpcap was compiled on a machine without pf support");
+       bpf_error(cstate, "libpcap was compiled on a machine without pf support");
        /*NOTREACHED*/
 
        /* this is to make the VC compiler happy */
@@ -342,7 +344,7 @@ pfaction_to_num(const char *action)
 %%
 prog:    null expr
 {
-       finish_parse($2.b);
+       finish_parse(cstate, $2.b);
 }
        | null
        ;
@@ -359,48 +361,48 @@ and:        AND                   { $$ = $<blk>0; }
 or:      OR                    { $$ = $<blk>0; }
        ;
 id:      nid
-       | pnum                  { $$.b = gen_ncode(NULL, (bpf_u_int32)$1,
+       | pnum                  { $$.b = gen_ncode(cstate, NULL, (bpf_u_int32)$1,
                                                   $$.q = $<blk>0.q); }
        | paren pid ')'         { $$ = $2; }
        ;
-nid:     ID                    { $$.b = gen_scode($1, $$.q = $<blk>0.q); }
-       | HID '/' NUM           { $$.b = gen_mcode($1, NULL, $3,
+nid:     ID                    { $$.b = gen_scode(cstate, $1, $$.q = $<blk>0.q); }
+       | HID '/' NUM           { $$.b = gen_mcode(cstate, $1, NULL, $3,
                                    $$.q = $<blk>0.q); }
-       | HID NETMASK HID       { $$.b = gen_mcode($1, $3, 0,
+       | HID NETMASK HID       { $$.b = gen_mcode(cstate, $1, $3, 0,
                                    $$.q = $<blk>0.q); }
        | HID                   {
                                  /* Decide how to parse HID based on proto */
                                  $$.q = $<blk>0.q;
                                  if ($$.q.addr == Q_PORT)
-                                       bpf_error("'port' modifier applied to ip host");
+                                       bpf_error(cstate, "'port' modifier applied to ip host");
                                  else if ($$.q.addr == Q_PORTRANGE)
-                                       bpf_error("'portrange' modifier applied to ip host");
+                                       bpf_error(cstate, "'portrange' modifier applied to ip host");
                                  else if ($$.q.addr == Q_PROTO)
-                                       bpf_error("'proto' modifier applied to ip host");
+                                       bpf_error(cstate, "'proto' modifier applied to ip host");
                                  else if ($$.q.addr == Q_PROTOCHAIN)
-                                       bpf_error("'protochain' modifier applied to ip host");
-                                 $$.b = gen_ncode($1, 0, $$.q);
+                                       bpf_error(cstate, "'protochain' modifier applied to ip host");
+                                 $$.b = gen_ncode(cstate, $1, 0, $$.q);
                                }
        | HID6 '/' NUM          {
 #ifdef INET6
-                                 $$.b = gen_mcode6($1, NULL, $3,
+                                 $$.b = gen_mcode6(cstate, $1, NULL, $3,
                                    $$.q = $<blk>0.q);
 #else
-                                 bpf_error("'ip6addr/prefixlen' not supported "
+                                 bpf_error(cstate, "'ip6addr/prefixlen' not supported "
                                        "in this configuration");
 #endif /*INET6*/
                                }
        | HID6                  {
 #ifdef INET6
-                                 $$.b = gen_mcode6($1, 0, 128,
+                                 $$.b = gen_mcode6(cstate, $1, 0, 128,
                                    $$.q = $<blk>0.q);
 #else
-                                 bpf_error("'ip6addr' not supported "
+                                 bpf_error(cstate, "'ip6addr' not supported "
                                        "in this configuration");
 #endif /*INET6*/
                                }
        | EID                   {
-                                 $$.b = gen_ecode($1, $$.q = $<blk>0.q);
+                                 $$.b = gen_ecode(cstate, $1, $$.q = $<blk>0.q);
                                  /*
                                   * $1 was allocated by "pcap_ether_aton()",
                                   * so we must free it now that we're done
@@ -409,7 +411,7 @@ nid:          ID                    { $$.b = gen_scode($1, $$.q = $<blk>0.q); }
                                  free($1);
                                }
        | AID                   {
-                                 $$.b = gen_acode($1, $$.q = $<blk>0.q);
+                                 $$.b = gen_acode(cstate, $1, $$.q = $<blk>0.q);
                                  /*
                                   * $1 was allocated by "pcap_ether_aton()",
                                   * so we must free it now that we're done
@@ -427,7 +429,7 @@ pid:          nid
        | qid and id            { gen_and($1.b, $3.b); $$ = $3; }
        | qid or id             { gen_or($1.b, $3.b); $$ = $3; }
        ;
-qid:     pnum                  { $$.b = gen_ncode(NULL, (bpf_u_int32)$1,
+qid:     pnum                  { $$.b = gen_ncode(cstate, NULL, (bpf_u_int32)$1,
                                                   $$.q = $<blk>0.q); }
        | pid
        ;
@@ -443,16 +445,16 @@ head:       pqual dqual aqual     { QSET($$.q, $1, $2, $3); }
        ;
 rterm:   head id               { $$ = $2; }
        | paren expr ')'        { $$.b = $2.b; $$.q = $1.q; }
-       | pname                 { $$.b = gen_proto_abbrev($1); $$.q = qerr; }
-       | arth relop arth       { $$.b = gen_relation($2, $1, $3, 0);
+       | pname                 { $$.b = gen_proto_abbrev(cstate, $1); $$.q = qerr; }
+       | arth relop arth       { $$.b = gen_relation(cstate, $2, $1, $3, 0);
                                  $$.q = qerr; }
-       | arth irelop arth      { $$.b = gen_relation($2, $1, $3, 1);
+       | arth irelop arth      { $$.b = gen_relation(cstate, $2, $1, $3, 1);
                                  $$.q = qerr; }
        | other                 { $$.b = $1; $$.q = qerr; }
-       | atmtype               { $$.b = gen_atmtype_abbrev($1); $$.q = qerr; }
-       | atmmultitype          { $$.b = gen_atmmulti_abbrev($1); $$.q = qerr; }
+       | atmtype               { $$.b = gen_atmtype_abbrev(cstate, $1); $$.q = qerr; }
+       | atmmultitype          { $$.b = gen_atmmulti_abbrev(cstate, $1); $$.q = qerr; }
        | atmfield atmvalue     { $$.b = $2.b; $$.q = qerr; }
-       | mtp2type              { $$.b = gen_mtp2type_abbrev($1); $$.q = qerr; }
+       | mtp2type              { $$.b = gen_mtp2type_abbrev(cstate, $1); $$.q = qerr; }
        | mtp3field mtp3value   { $$.b = $2.b; $$.q = qerr; }
        ;
 /* protocol level qualifiers */
@@ -522,54 +524,54 @@ pname:      LINK                  { $$ = Q_LINK; }
        | NETBEUI               { $$ = Q_NETBEUI; }
        | RADIO                 { $$ = Q_RADIO; }
        ;
-other:   pqual TK_BROADCAST    { $$ = gen_broadcast($1); }
-       | pqual TK_MULTICAST    { $$ = gen_multicast($1); }
-       | LESS NUM              { $$ = gen_less($2); }
-       | GREATER NUM           { $$ = gen_greater($2); }
-       | CBYTE NUM byteop NUM  { $$ = gen_byteop($3, $2, $4); }
-       | INBOUND               { $$ = gen_inbound(0); }
-       | OUTBOUND              { $$ = gen_inbound(1); }
-       | VLAN pnum             { $$ = gen_vlan($2); }
-       | VLAN                  { $$ = gen_vlan(-1); }
-       | MPLS pnum             { $$ = gen_mpls($2); }
-       | MPLS                  { $$ = gen_mpls(-1); }
-       | PPPOED                { $$ = gen_pppoed(); }
-       | PPPOES pnum           { $$ = gen_pppoes($2); }
-       | PPPOES                { $$ = gen_pppoes(-1); }
-       | GENEVE pnum           { $$ = gen_geneve($2); }
-       | GENEVE                { $$ = gen_geneve(-1); }
+other:   pqual TK_BROADCAST    { $$ = gen_broadcast(cstate, $1); }
+       | pqual TK_MULTICAST    { $$ = gen_multicast(cstate, $1); }
+       | LESS NUM              { $$ = gen_less(cstate, $2); }
+       | GREATER NUM           { $$ = gen_greater(cstate, $2); }
+       | CBYTE NUM byteop NUM  { $$ = gen_byteop(cstate, $3, $2, $4); }
+       | INBOUND               { $$ = gen_inbound(cstate, 0); }
+       | OUTBOUND              { $$ = gen_inbound(cstate, 1); }
+       | VLAN pnum             { $$ = gen_vlan(cstate, $2); }
+       | VLAN                  { $$ = gen_vlan(cstate, -1); }
+       | MPLS pnum             { $$ = gen_mpls(cstate, $2); }
+       | MPLS                  { $$ = gen_mpls(cstate, -1); }
+       | PPPOED                { $$ = gen_pppoed(cstate); }
+       | PPPOES pnum           { $$ = gen_pppoes(cstate, $2); }
+       | PPPOES                { $$ = gen_pppoes(cstate, -1); }
+       | GENEVE pnum           { $$ = gen_geneve(cstate, $2); }
+       | GENEVE                { $$ = gen_geneve(cstate, -1); }
        | pfvar                 { $$ = $1; }
        | pqual p80211          { $$ = $2; }
        | pllc                  { $$ = $1; }
        ;
 
-pfvar:   PF_IFNAME ID          { $$ = gen_pf_ifname($2); }
-       | PF_RSET ID            { $$ = gen_pf_ruleset($2); }
-       | PF_RNR NUM            { $$ = gen_pf_rnr($2); }
-       | PF_SRNR NUM           { $$ = gen_pf_srnr($2); }
-       | PF_REASON reason      { $$ = gen_pf_reason($2); }
-       | PF_ACTION action      { $$ = gen_pf_action($2); }
+pfvar:   PF_IFNAME ID          { $$ = gen_pf_ifname(cstate, $2); }
+       | PF_RSET ID            { $$ = gen_pf_ruleset(cstate, $2); }
+       | PF_RNR NUM            { $$ = gen_pf_rnr(cstate, $2); }
+       | PF_SRNR NUM           { $$ = gen_pf_srnr(cstate, $2); }
+       | PF_REASON reason      { $$ = gen_pf_reason(cstate, $2); }
+       | PF_ACTION action      { $$ = gen_pf_action(cstate, $2); }
        ;
 
 p80211:   TYPE type SUBTYPE subtype
-                               { $$ = gen_p80211_type($2 | $4,
+                               { $$ = gen_p80211_type(cstate, $2 | $4,
                                        IEEE80211_FC0_TYPE_MASK |
                                        IEEE80211_FC0_SUBTYPE_MASK);
                                }
-       | TYPE type             { $$ = gen_p80211_type($2,
+       | TYPE type             { $$ = gen_p80211_type(cstate, $2,
                                        IEEE80211_FC0_TYPE_MASK);
                                }
-       | SUBTYPE type_subtype  { $$ = gen_p80211_type($2,
+       | SUBTYPE type_subtype  { $$ = gen_p80211_type(cstate, $2,
                                        IEEE80211_FC0_TYPE_MASK |
                                        IEEE80211_FC0_SUBTYPE_MASK);
                                }
-       | DIR dir               { $$ = gen_p80211_fcdir($2); }
+       | DIR dir               { $$ = gen_p80211_fcdir(cstate, $2); }
        ;
 
 type:    NUM
        | ID                    { $$ = str2tok($1, ieee80211_types);
                                  if ($$ == -1)
-                                       bpf_error("unknown 802.11 type name");
+                                       bpf_error(cstate, "unknown 802.11 type name");
                                }
        ;
 
@@ -579,7 +581,7 @@ subtype:  NUM
                                  for (i = 0;; i++) {
                                        if (ieee80211_type_subtypes[i].tok == NULL) {
                                                /* Ran out of types */
-                                               bpf_error("unknown 802.11 type");
+                                               bpf_error(cstate, "unknown 802.11 type");
                                                break;
                                        }
                                        if ($<i>-1 == ieee80211_type_subtypes[i].type) {
@@ -590,7 +592,7 @@ subtype:  NUM
 
                                  $$ = str2tok($1, types);
                                  if ($$ == -1)
-                                       bpf_error("unknown 802.11 subtype name");
+                                       bpf_error(cstate, "unknown 802.11 subtype name");
                                }
        ;
 
@@ -598,7 +600,7 @@ type_subtype:       ID              { int i;
                                  for (i = 0;; i++) {
                                        if (ieee80211_type_subtypes[i].tok == NULL) {
                                                /* Ran out of types */
-                                               bpf_error("unknown 802.11 type name");
+                                               bpf_error(cstate, "unknown 802.11 type name");
                                                break;
                                        }
                                        $$ = str2tok($1, ieee80211_type_subtypes[i].tok);
@@ -610,29 +612,29 @@ type_subtype:     ID              { int i;
                                }
                ;
 
-pllc:  LLC                     { $$ = gen_llc(); }
+pllc:  LLC                     { $$ = gen_llc(cstate); }
        | LLC ID                { if (pcap_strcasecmp($2, "i") == 0)
-                                       $$ = gen_llc_i();
+                                       $$ = gen_llc_i(cstate);
                                  else if (pcap_strcasecmp($2, "s") == 0)
-                                       $$ = gen_llc_s();
+                                       $$ = gen_llc_s(cstate);
                                  else if (pcap_strcasecmp($2, "u") == 0)
-                                       $$ = gen_llc_u();
+                                       $$ = gen_llc_u(cstate);
                                  else {
                                        u_int subtype;
 
                                        subtype = str2tok($2, llc_s_subtypes);
                                        if (subtype != -1)
-                                               $$ = gen_llc_s_subtype(subtype);
+                                               $$ = gen_llc_s_subtype(cstate, subtype);
                                        else {
                                                subtype = str2tok($2, llc_u_subtypes);
                                                if (subtype == -1)
-                                                       bpf_error("unknown LLC type name \"%s\"", $2);
-                                               $$ = gen_llc_u_subtype(subtype);
+                                                       bpf_error(cstate, "unknown LLC type name \"%s\"", $2);
+                                               $$ = gen_llc_u_subtype(cstate, subtype);
                                        }
                                  }
                                }
                                /* sigh, "rnr" is already a keyword for PF */
-       | LLC PF_RNR            { $$ = gen_llc_s_subtype(LLC_RNR); }
+       | LLC PF_RNR            { $$ = gen_llc_s_subtype(cstate, LLC_RNR); }
        ;
 
 dir:     NUM
@@ -645,15 +647,15 @@ dir:        NUM
                                  else if (pcap_strcasecmp($1, "dstods") == 0)
                                        $$ = IEEE80211_FC1_DIR_DSTODS;
                                  else
-                                       bpf_error("unknown 802.11 direction");
+                                       bpf_error(cstate, "unknown 802.11 direction");
                                }
        ;
 
 reason:          NUM                   { $$ = $1; }
-       | ID                    { $$ = pfreason_to_num($1); }
+       | ID                    { $$ = pfreason_to_num(cstate, $1); }
        ;
 
-action:          ID                    { $$ = pfaction_to_num($1); }
+action:          ID                    { $$ = pfaction_to_num(cstate, $1); }
        ;
 
 relop:   '>'                   { $$ = BPF_JGT; }
@@ -664,24 +666,24 @@ irelop:     LEQ                   { $$ = BPF_JGT; }
        | '<'                   { $$ = BPF_JGE; }
        | NEQ                   { $$ = BPF_JEQ; }
        ;
-arth:    pnum                  { $$ = gen_loadi($1); }
+arth:    pnum                  { $$ = gen_loadi(cstate, $1); }
        | narth
        ;
-narth:   pname '[' arth ']'            { $$ = gen_load($1, $3, 1); }
-       | pname '[' arth ':' NUM ']'    { $$ = gen_load($1, $3, $5); }
-       | arth '+' arth                 { $$ = gen_arth(BPF_ADD, $1, $3); }
-       | arth '-' arth                 { $$ = gen_arth(BPF_SUB, $1, $3); }
-       | arth '*' arth                 { $$ = gen_arth(BPF_MUL, $1, $3); }
-       | arth '/' arth                 { $$ = gen_arth(BPF_DIV, $1, $3); }
-       | arth '%' arth                 { $$ = gen_arth(BPF_MOD, $1, $3); }
-       | arth '&' arth                 { $$ = gen_arth(BPF_AND, $1, $3); }
-       | arth '|' arth                 { $$ = gen_arth(BPF_OR, $1, $3); }
-       | arth '^' arth                 { $$ = gen_arth(BPF_XOR, $1, $3); }
-       | arth LSH arth                 { $$ = gen_arth(BPF_LSH, $1, $3); }
-       | arth RSH arth                 { $$ = gen_arth(BPF_RSH, $1, $3); }
-       | '-' arth %prec UMINUS         { $$ = gen_neg($2); }
+narth:   pname '[' arth ']'            { $$ = gen_load(cstate, $1, $3, 1); }
+       | pname '[' arth ':' NUM ']'    { $$ = gen_load(cstate, $1, $3, $5); }
+       | arth '+' arth                 { $$ = gen_arth(cstate, BPF_ADD, $1, $3); }
+       | arth '-' arth                 { $$ = gen_arth(cstate, BPF_SUB, $1, $3); }
+       | arth '*' arth                 { $$ = gen_arth(cstate, BPF_MUL, $1, $3); }
+       | arth '/' arth                 { $$ = gen_arth(cstate, BPF_DIV, $1, $3); }
+       | arth '%' arth                 { $$ = gen_arth(cstate, BPF_MOD, $1, $3); }
+       | arth '&' arth                 { $$ = gen_arth(cstate, BPF_AND, $1, $3); }
+       | arth '|' arth                 { $$ = gen_arth(cstate, BPF_OR, $1, $3); }
+       | arth '^' arth                 { $$ = gen_arth(cstate, BPF_XOR, $1, $3); }
+       | arth LSH arth                 { $$ = gen_arth(cstate, BPF_LSH, $1, $3); }
+       | arth RSH arth                 { $$ = gen_arth(cstate, BPF_RSH, $1, $3); }
+       | '-' arth %prec UMINUS         { $$ = gen_neg(cstate, $2); }
        | paren narth ')'               { $$ = $2; }
-       | LEN                           { $$ = gen_loadlen(); }
+       | LEN                           { $$ = gen_loadlen(cstate); }
        ;
 byteop:          '&'                   { $$ = '&'; }
        | '|'                   { $$ = '|'; }
@@ -710,15 +712,15 @@ atmfield: VPI                     { $$.atmfieldtype = A_VPI; }
        | VCI                   { $$.atmfieldtype = A_VCI; }
        ;
 atmvalue: atmfieldvalue
-       | relop NUM             { $$.b = gen_atmfield_code($<blk>0.atmfieldtype, (bpf_int32)$2, (bpf_u_int32)$1, 0); }
-       | irelop NUM            { $$.b = gen_atmfield_code($<blk>0.atmfieldtype, (bpf_int32)$2, (bpf_u_int32)$1, 1); }
+       | relop NUM             { $$.b = gen_atmfield_code(cstate, $<blk>0.atmfieldtype, (bpf_int32)$2, (bpf_u_int32)$1, 0); }
+       | irelop NUM            { $$.b = gen_atmfield_code(cstate, $<blk>0.atmfieldtype, (bpf_int32)$2, (bpf_u_int32)$1, 1); }
        | paren atmlistvalue ')' { $$.b = $2.b; $$.q = qerr; }
        ;
 atmfieldvalue: NUM {
        $$.atmfieldtype = $<blk>0.atmfieldtype;
        if ($$.atmfieldtype == A_VPI ||
            $$.atmfieldtype == A_VCI)
-               $$.b = gen_atmfield_code($$.atmfieldtype, (bpf_int32) $1, BPF_JEQ, 0);
+               $$.b = gen_atmfield_code(cstate, $$.atmfieldtype, (bpf_int32) $1, BPF_JEQ, 0);
        }
        ;
 atmlistvalue: atmfieldvalue
@@ -743,8 +745,8 @@ mtp3field: SIO                      { $$.mtp3fieldtype = M_SIO; }
        | HSLS                  { $$.mtp3fieldtype = MH_SLS; }
        ;
 mtp3value: mtp3fieldvalue
-       | relop NUM             { $$.b = gen_mtp3field_code($<blk>0.mtp3fieldtype, (u_int)$2, (u_int)$1, 0); }
-       | irelop NUM            { $$.b = gen_mtp3field_code($<blk>0.mtp3fieldtype, (u_int)$2, (u_int)$1, 1); }
+       | relop NUM             { $$.b = gen_mtp3field_code(cstate, $<blk>0.mtp3fieldtype, (u_int)$2, (u_int)$1, 0); }
+       | irelop NUM            { $$.b = gen_mtp3field_code(cstate, $<blk>0.mtp3fieldtype, (u_int)$2, (u_int)$1, 1); }
        | paren mtp3listvalue ')' { $$.b = $2.b; $$.q = qerr; }
        ;
 mtp3fieldvalue: NUM {
@@ -757,7 +759,7 @@ mtp3fieldvalue: NUM {
            $$.mtp3fieldtype == MH_OPC ||
            $$.mtp3fieldtype == MH_DPC ||
            $$.mtp3fieldtype == MH_SLS)
-               $$.b = gen_mtp3field_code($$.mtp3fieldtype, (u_int) $1, BPF_JEQ, 0);
+               $$.b = gen_mtp3field_code(cstate, $$.mtp3fieldtype, (u_int) $1, BPF_JEQ, 0);
        }
        ;
 mtp3listvalue: mtp3fieldvalue
index 5905f5f2f403f0a9297fddbc105186b115fca717..bcff10383d3c1acf2de54a48d58fd087a4c033f9 100644 (file)
@@ -425,7 +425,7 @@ __pcap_atodn(const char *s, bpf_u_int32 *addr)
        u_int node, area;
 
        if (sscanf(s, "%d.%d", &area, &node) != 2)
-               bpf_error("malformed decnet address '%s'", s);
+               return(0);
 
        *addr = (area << AREASHIFT) & AREAMASK;
        *addr |= (node & NODEMASK);
@@ -529,8 +529,8 @@ pcap_ether_hostton(const char *name)
 }
 #endif
 
-u_short
-__pcap_nametodnaddr(const char *name)
+int
+__pcap_nametodnaddr(const char *name, u_short *res)
 {
 #ifdef DECNETLIB
        struct nodeent *getnodebyname();
@@ -539,13 +539,11 @@ __pcap_nametodnaddr(const char *name)
 
        nep = getnodebyname(name);
        if (nep == ((struct nodeent *)0))
-               bpf_error("unknown decnet host name '%s'\n", name);
+               return(0);
 
-       memcpy((char *)&res, (char *)nep->n_addr, sizeof(unsigned short));
-       return(res);
+       memcpy((char *)res, (char *)nep->n_addr, sizeof(unsigned short));
+       return(1);
 #else
-       bpf_error("decnet name support not included, '%s' cannot be translated\n",
-               name);
        return(0);
 #endif
 }
index 3d6754a1bf974ea36b43d3b1b8cfe7c2056338e1..fd6b7e101640faacf78aa07a50edf42dea054410 100644 (file)
@@ -41,7 +41,7 @@ extern "C" {
  */
 int __pcap_atodn(const char *, bpf_u_int32 *);
 int __pcap_atoin(const char *, bpf_u_int32 *);
-u_short        __pcap_nametodnaddr(const char *);
+int __pcap_nametodnaddr(const char *, u_short *);
 
 #ifdef __cplusplus
 }
index 714194539c4e49ff886aac7589c4d6da9c87fec7..2b4b358eb16498b63c39a24de4ce1d809b9b3942 100644 (file)
@@ -107,45 +107,48 @@ ffs(int mask)
 #define AX_ATOM N_ATOMS
 
 /*
- * A flag to indicate that further optimization is needed.
- * Iterative passes are continued until a given pass yields no
- * branch movement.
+ * These data structures are used in a Cocke and Shwarz style
+ * value numbering scheme.  Since the flowgraph is acyclic,
+ * exit values can be propagated from a node's predecessors
+ * provided it is uniquely defined.
  */
-static int done;
+struct valnode {
+       int code;
+       int v0, v1;
+       int val;
+       struct valnode *next;
+};
 
-/*
- * A block is marked if only if its mark equals the current mark.
- * Rather than traverse the code array, marking each item, 'cur_mark' is
- * incremented.  This automatically makes each element unmarked.
- */
-static int cur_mark;
-#define isMarked(p) ((p)->mark == cur_mark)
-#define unMarkAll() cur_mark += 1
-#define Mark(p) ((p)->mark = cur_mark)
+/* Integer constants mapped with the load immediate opcode. */
+#define K(i) F(opt_state, BPF_LD|BPF_IMM|BPF_W, i, 0L)
 
-static void opt_init(struct block *);
-static void opt_cleanup(void);
+struct vmapinfo {
+       int is_const;
+       bpf_int32 const_val;
+};
 
-static void intern_blocks(struct block *);
+struct _opt_state {
+       /*
+        * A flag to indicate that further optimization is needed.
+        * Iterative passes are continued until a given pass yields no
+        * branch movement.
+        */
+       int done;
 
-static void find_inedges(struct block *);
-#ifdef BDEBUG
-static void opt_dump(struct block *);
-#endif
+       int n_blocks;
+       struct block **blocks;
+       int n_edges;
+       struct edge **edges;
 
-static int n_blocks;
-struct block **blocks;
-static int n_edges;
-struct edge **edges;
+       /*
+        * A bit vector set representation of the dominators.
+        * We round up the set size to the next power of two.
+        */
+       int nodewords;
+       int edgewords;
+       struct block **levels;
+       bpf_u_int32 *space;
 
-/*
- * A bit vector set representation of the dominators.
- * We round up the set size to the next power of two.
- */
-static int nodewords;
-static int edgewords;
-struct block **levels;
-bpf_u_int32 *space;
 #define BITS_PER_WORD (8*sizeof(bpf_u_int32))
 /*
  * True if a is in uset {p}
@@ -195,48 +198,79 @@ bpf_u_int32 *space;
        while (--_n >= 0) *_x++ |= *_y++;\
 }
 
-static uset all_dom_sets;
-static uset all_closure_sets;
-static uset all_edge_sets;
+       uset all_dom_sets;
+       uset all_closure_sets;
+       uset all_edge_sets;
+
+#define MODULUS 213
+       struct valnode *hashtbl[MODULUS];
+       int curval;
+       int maxval;
+
+       struct vmapinfo *vmap;
+       struct valnode *vnode_base;
+       struct valnode *next_vnode;
+};
+
+typedef struct {
+       /*
+        * Some pointers used to convert the basic block form of the code,
+        * into the array form that BPF requires.  'fstart' will point to
+        * the malloc'd array while 'ftail' is used during the recursive
+        * traversal.
+        */
+       struct bpf_insn *fstart;
+       struct bpf_insn *ftail;
+} conv_state_t;
+
+static void opt_init(compiler_state_t *, opt_state_t *, struct icode *);
+static void opt_cleanup(opt_state_t *);
+
+static void intern_blocks(opt_state_t *, struct icode *);
+
+static void find_inedges(opt_state_t *, struct block *);
+#ifdef BDEBUG
+static void opt_dump(compiler_state_t *, struct icode *);
+#endif
 
 #ifndef MAX
 #define MAX(a,b) ((a)>(b)?(a):(b))
 #endif
 
 static void
-find_levels_r(struct block *b)
+find_levels_r(opt_state_t *opt_state, struct icode *ic, struct block *b)
 {
        int level;
 
-       if (isMarked(b))
+       if (isMarked(ic, b))
                return;
 
-       Mark(b);
+       Mark(ic, b);
        b->link = 0;
 
        if (JT(b)) {
-               find_levels_r(JT(b));
-               find_levels_r(JF(b));
+               find_levels_r(opt_state, ic, JT(b));
+               find_levels_r(opt_state, ic, JF(b));
                level = MAX(JT(b)->level, JF(b)->level) + 1;
        } else
                level = 0;
        b->level = level;
-       b->link = levels[level];
-       levels[level] = b;
+       b->link = opt_state->levels[level];
+       opt_state->levels[level] = b;
 }
 
 /*
  * Level graph.  The levels go from 0 at the leaves to
- * N_LEVELS at the root.  The levels[] array points to the
+ * N_LEVELS at the root.  The opt_state->levels[] array points to the
  * first node of the level list, whose elements are linked
  * with the 'link' field of the struct block.
  */
 static void
-find_levels(struct block *root)
+find_levels(opt_state_t *opt_state, struct icode *ic)
 {
-       memset((char *)levels, 0, n_blocks * sizeof(*levels));
-       unMarkAll();
-       find_levels_r(root);
+       memset((char *)opt_state->levels, 0, opt_state->n_blocks * sizeof(*opt_state->levels));
+       unMarkAll(ic);
+       find_levels_r(opt_state, ic, ic->root);
 }
 
 /*
@@ -244,7 +278,7 @@ find_levels(struct block *root)
  * Assumes graph has been leveled.
  */
 static void
-find_dom(struct block *root)
+find_dom(opt_state_t *opt_state, struct block *root)
 {
        int i;
        struct block *b;
@@ -253,33 +287,33 @@ find_dom(struct block *root)
        /*
         * Initialize sets to contain all nodes.
         */
-       x = all_dom_sets;
-       i = n_blocks * nodewords;
+       x = opt_state->all_dom_sets;
+       i = opt_state->n_blocks * opt_state->nodewords;
        while (--i >= 0)
                *x++ = ~0;
        /* Root starts off empty. */
-       for (i = nodewords; --i >= 0;)
+       for (i = opt_state->nodewords; --i >= 0;)
                root->dom[i] = 0;
 
        /* root->level is the highest level no found. */
        for (i = root->level; i >= 0; --i) {
-               for (b = levels[i]; b; b = b->link) {
+               for (b = opt_state->levels[i]; b; b = b->link) {
                        SET_INSERT(b->dom, b->id);
                        if (JT(b) == 0)
                                continue;
-                       SET_INTERSECT(JT(b)->dom, b->dom, nodewords);
-                       SET_INTERSECT(JF(b)->dom, b->dom, nodewords);
+                       SET_INTERSECT(JT(b)->dom, b->dom, opt_state->nodewords);
+                       SET_INTERSECT(JF(b)->dom, b->dom, opt_state->nodewords);
                }
        }
 }
 
 static void
-propedom(struct edge *ep)
+propedom(opt_state_t *opt_state, struct edge *ep)
 {
        SET_INSERT(ep->edom, ep->id);
        if (ep->succ) {
-               SET_INTERSECT(ep->succ->et.edom, ep->edom, edgewords);
-               SET_INTERSECT(ep->succ->ef.edom, ep->edom, edgewords);
+               SET_INTERSECT(ep->succ->et.edom, ep->edom, opt_state->edgewords);
+               SET_INTERSECT(ep->succ->ef.edom, ep->edom, opt_state->edgewords);
        }
 }
 
@@ -288,23 +322,23 @@ propedom(struct edge *ep)
  * Assumes graph has been leveled and predecessors established.
  */
 static void
-find_edom(struct block *root)
+find_edom(opt_state_t *opt_state, struct block *root)
 {
        int i;
        uset x;
        struct block *b;
 
-       x = all_edge_sets;
-       for (i = n_edges * edgewords; --i >= 0; )
+       x = opt_state->all_edge_sets;
+       for (i = opt_state->n_edges * opt_state->edgewords; --i >= 0; )
                x[i] = ~0;
 
        /* root->level is the highest level no found. */
-       memset(root->et.edom, 0, edgewords * sizeof(*(uset)0));
-       memset(root->ef.edom, 0, edgewords * sizeof(*(uset)0));
+       memset(root->et.edom, 0, opt_state->edgewords * sizeof(*(uset)0));
+       memset(root->ef.edom, 0, opt_state->edgewords * sizeof(*(uset)0));
        for (i = root->level; i >= 0; --i) {
-               for (b = levels[i]; b != 0; b = b->link) {
-                       propedom(&b->et);
-                       propedom(&b->ef);
+               for (b = opt_state->levels[i]; b != 0; b = b->link) {
+                       propedom(opt_state, &b->et);
+                       propedom(opt_state, &b->ef);
                }
        }
 }
@@ -317,7 +351,7 @@ find_edom(struct block *root)
  * Assumes graph has been leveled.
  */
 static void
-find_closure(struct block *root)
+find_closure(opt_state_t *opt_state, struct block *root)
 {
        int i;
        struct block *b;
@@ -325,17 +359,17 @@ find_closure(struct block *root)
        /*
         * Initialize sets to contain no nodes.
         */
-       memset((char *)all_closure_sets, 0,
-             n_blocks * nodewords * sizeof(*all_closure_sets));
+       memset((char *)opt_state->all_closure_sets, 0,
+             opt_state->n_blocks * opt_state->nodewords * sizeof(*opt_state->all_closure_sets));
 
        /* root->level is the highest level no found. */
        for (i = root->level; i >= 0; --i) {
-               for (b = levels[i]; b; b = b->link) {
+               for (b = opt_state->levels[i]; b; b = b->link) {
                        SET_INSERT(b->closure, b->id);
                        if (JT(b) == 0)
                                continue;
-                       SET_UNION(JT(b)->closure, b->closure, nodewords);
-                       SET_UNION(JF(b)->closure, b->closure, nodewords);
+                       SET_UNION(JT(b)->closure, b->closure, opt_state->nodewords);
+                       SET_UNION(JF(b)->closure, b->closure, opt_state->nodewords);
                }
        }
 }
@@ -489,7 +523,7 @@ compute_local_ud(struct block *b)
  * Assume graph is already leveled.
  */
 static void
-find_ud(struct block *root)
+find_ud(opt_state_t *opt_state, struct block *root)
 {
        int i, maxlevel;
        struct block *p;
@@ -500,61 +534,30 @@ find_ud(struct block *root)
         */
        maxlevel = root->level;
        for (i = maxlevel; i >= 0; --i)
-               for (p = levels[i]; p; p = p->link) {
+               for (p = opt_state->levels[i]; p; p = p->link) {
                        compute_local_ud(p);
                        p->out_use = 0;
                }
 
        for (i = 1; i <= maxlevel; ++i) {
-               for (p = levels[i]; p; p = p->link) {
+               for (p = opt_state->levels[i]; p; p = p->link) {
                        p->out_use |= JT(p)->in_use | JF(p)->in_use;
                        p->in_use |= p->out_use &~ p->kill;
                }
        }
 }
-
-/*
- * These data structures are used in a Cocke and Shwarz style
- * value numbering scheme.  Since the flowgraph is acyclic,
- * exit values can be propagated from a node's predecessors
- * provided it is uniquely defined.
- */
-struct valnode {
-       int code;
-       int v0, v1;
-       int val;
-       struct valnode *next;
-};
-
-#define MODULUS 213
-static struct valnode *hashtbl[MODULUS];
-static int curval;
-static int maxval;
-
-/* Integer constants mapped with the load immediate opcode. */
-#define K(i) F(BPF_LD|BPF_IMM|BPF_W, i, 0L)
-
-struct vmapinfo {
-       int is_const;
-       bpf_int32 const_val;
-};
-
-struct vmapinfo *vmap;
-struct valnode *vnode_base;
-struct valnode *next_vnode;
-
 static void
-init_val(void)
+init_val(opt_state_t *opt_state)
 {
-       curval = 0;
-       next_vnode = vnode_base;
-       memset((char *)vmap, 0, maxval * sizeof(*vmap));
-       memset((char *)hashtbl, 0, sizeof hashtbl);
+       opt_state->curval = 0;
+       opt_state->next_vnode = opt_state->vnode_base;
+       memset((char *)opt_state->vmap, 0, opt_state->maxval * sizeof(*opt_state->vmap));
+       memset((char *)opt_state->hashtbl, 0, sizeof opt_state->hashtbl);
 }
 
 /* Because we really don't have an IR, this stuff is a little messy. */
 static int
-F(int code, int v0, int v1)
+F(opt_state_t *opt_state, int code, int v0, int v1)
 {
        u_int hash;
        int val;
@@ -563,23 +566,23 @@ F(int code, int v0, int v1)
        hash = (u_int)code ^ (v0 << 4) ^ (v1 << 8);
        hash %= MODULUS;
 
-       for (p = hashtbl[hash]; p; p = p->next)
+       for (p = opt_state->hashtbl[hash]; p; p = p->next)
                if (p->code == code && p->v0 == v0 && p->v1 == v1)
                        return p->val;
 
-       val = ++curval;
+       val = ++opt_state->curval;
        if (BPF_MODE(code) == BPF_IMM &&
            (BPF_CLASS(code) == BPF_LD || BPF_CLASS(code) == BPF_LDX)) {
-               vmap[val].const_val = v0;
-               vmap[val].is_const = 1;
+               opt_state->vmap[val].const_val = v0;
+               opt_state->vmap[val].is_const = 1;
        }
-       p = next_vnode++;
+       p = opt_state->next_vnode++;
        p->val = val;
        p->code = code;
        p->v0 = v0;
        p->v1 = v1;
-       p->next = hashtbl[hash];
-       hashtbl[hash] = p;
+       p->next = opt_state->hashtbl[hash];
+       opt_state->hashtbl[hash] = p;
 
        return val;
 }
@@ -598,12 +601,13 @@ vstore(struct stmt *s, int *valp, int newval, int alter)
  * (Unary operators are handled elsewhere.)
  */
 static void
-fold_op(struct stmt *s, int v0, int v1)
+fold_op(compiler_state_t *cstate, struct icode *ic, opt_state_t *opt_state,
+    struct stmt *s, int v0, int v1)
 {
        bpf_u_int32 a, b;
 
-       a = vmap[v0].const_val;
-       b = vmap[v1].const_val;
+       a = opt_state->vmap[v0].const_val;
+       b = opt_state->vmap[v1].const_val;
 
        switch (BPF_OP(s->code)) {
        case BPF_ADD:
@@ -620,13 +624,13 @@ fold_op(struct stmt *s, int v0, int v1)
 
        case BPF_DIV:
                if (b == 0)
-                       bpf_error("division by zero");
+                       bpf_error(cstate, "division by zero");
                a /= b;
                break;
 
        case BPF_MOD:
                if (b == 0)
-                       bpf_error("modulus by zero");
+                       bpf_error(cstate, "modulus by zero");
                a %= b;
                break;
 
@@ -655,7 +659,7 @@ fold_op(struct stmt *s, int v0, int v1)
        }
        s->k = a;
        s->code = BPF_LD|BPF_IMM;
-       done = 0;
+       opt_state->done = 0;
 }
 
 static inline struct slist *
@@ -676,7 +680,7 @@ opt_not(struct block *b)
 }
 
 static void
-opt_peep(struct block *b)
+opt_peep(opt_state_t *opt_state, struct block *b)
 {
        struct slist *s;
        struct slist *next, *last;
@@ -711,7 +715,7 @@ opt_peep(struct block *b)
                if (s->s.code == BPF_ST &&
                    next->s.code == (BPF_LDX|BPF_MEM) &&
                    s->s.k == next->s.k) {
-                       done = 0;
+                       opt_state->done = 0;
                        next->s.code = BPF_MISC|BPF_TAX;
                }
                /*
@@ -722,7 +726,7 @@ opt_peep(struct block *b)
                    next->s.code == (BPF_MISC|BPF_TAX)) {
                        s->s.code = BPF_LDX|BPF_IMM;
                        next->s.code = BPF_MISC|BPF_TXA;
-                       done = 0;
+                       opt_state->done = 0;
                }
                /*
                 * This is an ugly special case, but it happens
@@ -801,7 +805,7 @@ opt_peep(struct block *b)
                        s->s.code = NOP;
                        add->s.code = NOP;
                        tax->s.code = NOP;
-                       done = 0;
+                       opt_state->done = 0;
                }
        }
        /*
@@ -819,7 +823,7 @@ opt_peep(struct block *b)
                 */
                if (last->s.code == (BPF_ALU|BPF_SUB|BPF_X)) {
                        val = b->val[X_ATOM];
-                       if (vmap[val].is_const) {
+                       if (opt_state->vmap[val].is_const) {
                                /*
                                 * If we have a subtract to do a comparison,
                                 * and the X register is a known constant,
@@ -829,9 +833,9 @@ opt_peep(struct block *b)
                                 * sub x  ->    nop
                                 * jeq #y       jeq #(x+y)
                                 */
-                               b->s.k += vmap[val].const_val;
+                               b->s.k += opt_state->vmap[val].const_val;
                                last->s.code = NOP;
-                               done = 0;
+                               opt_state->done = 0;
                        } else if (b->s.k == 0) {
                                /*
                                 * If the X register isn't a constant,
@@ -844,7 +848,7 @@ opt_peep(struct block *b)
                                 */
                                last->s.code = NOP;
                                b->s.code = BPF_JMP|BPF_JEQ|BPF_X;
-                               done = 0;
+                               opt_state->done = 0;
                        }
                }
                /*
@@ -856,7 +860,7 @@ opt_peep(struct block *b)
                else if (last->s.code == (BPF_ALU|BPF_SUB|BPF_K)) {
                        last->s.code = NOP;
                        b->s.k += last->s.k;
-                       done = 0;
+                       opt_state->done = 0;
                }
                /*
                 * And, similarly, a constant AND can be simplified
@@ -870,7 +874,7 @@ opt_peep(struct block *b)
                        b->s.k = last->s.k;
                        b->s.code = BPF_JMP|BPF_K|BPF_JSET;
                        last->s.code = NOP;
-                       done = 0;
+                       opt_state->done = 0;
                        opt_not(b);
                }
        }
@@ -890,8 +894,8 @@ opt_peep(struct block *b)
         * constant.
         */
        val = b->val[X_ATOM];
-       if (vmap[val].is_const && BPF_SRC(b->s.code) == BPF_X) {
-               bpf_int32 v = vmap[val].const_val;
+       if (opt_state->vmap[val].is_const && BPF_SRC(b->s.code) == BPF_X) {
+               bpf_int32 v = opt_state->vmap[val].const_val;
                b->s.code &= ~BPF_X;
                b->s.k = v;
        }
@@ -900,8 +904,8 @@ opt_peep(struct block *b)
         * comparison result.
         */
        val = b->val[A_ATOM];
-       if (vmap[val].is_const && BPF_SRC(b->s.code) == BPF_K) {
-               bpf_int32 v = vmap[val].const_val;
+       if (opt_state->vmap[val].is_const && BPF_SRC(b->s.code) == BPF_K) {
+               bpf_int32 v = opt_state->vmap[val].const_val;
                switch (BPF_OP(b->s.code)) {
 
                case BPF_JEQ:
@@ -924,7 +928,7 @@ opt_peep(struct block *b)
                        abort();
                }
                if (JF(b) != JT(b))
-                       done = 0;
+                       opt_state->done = 0;
                if (v)
                        JF(b) = JT(b);
                else
@@ -939,7 +943,8 @@ opt_peep(struct block *b)
  * evaluation and code transformations weren't folded together.
  */
 static void
-opt_stmt(struct stmt *s, int val[], int alter)
+opt_stmt(compiler_state_t *cstate, struct icode *ic, opt_state_t *opt_state,
+    struct stmt *s, int val[], int alter)
 {
        int op;
        int v;
@@ -949,7 +954,7 @@ opt_stmt(struct stmt *s, int val[], int alter)
        case BPF_LD|BPF_ABS|BPF_W:
        case BPF_LD|BPF_ABS|BPF_H:
        case BPF_LD|BPF_ABS|BPF_B:
-               v = F(s->code, s->k, 0L);
+               v = F(opt_state, s->code, s->k, 0L);
                vstore(s, &val[A_ATOM], v, alter);
                break;
 
@@ -957,19 +962,19 @@ opt_stmt(struct stmt *s, int val[], int alter)
        case BPF_LD|BPF_IND|BPF_H:
        case BPF_LD|BPF_IND|BPF_B:
                v = val[X_ATOM];
-               if (alter && vmap[v].is_const) {
+               if (alter && opt_state->vmap[v].is_const) {
                        s->code = BPF_LD|BPF_ABS|BPF_SIZE(s->code);
-                       s->k += vmap[v].const_val;
-                       v = F(s->code, s->k, 0L);
-                       done = 0;
+                       s->k += opt_state->vmap[v].const_val;
+                       v = F(opt_state, s->code, s->k, 0L);
+                       opt_state->done = 0;
                }
                else
-                       v = F(s->code, s->k, v);
+                       v = F(opt_state, s->code, s->k, v);
                vstore(s, &val[A_ATOM], v, alter);
                break;
 
        case BPF_LD|BPF_LEN:
-               v = F(s->code, 0L, 0L);
+               v = F(opt_state, s->code, 0L, 0L);
                vstore(s, &val[A_ATOM], v, alter);
                break;
 
@@ -984,18 +989,18 @@ opt_stmt(struct stmt *s, int val[], int alter)
                break;
 
        case BPF_LDX|BPF_MSH|BPF_B:
-               v = F(s->code, s->k, 0L);
+               v = F(opt_state, s->code, s->k, 0L);
                vstore(s, &val[X_ATOM], v, alter);
                break;
 
        case BPF_ALU|BPF_NEG:
-               if (alter && vmap[val[A_ATOM]].is_const) {
+               if (alter && opt_state->vmap[val[A_ATOM]].is_const) {
                        s->code = BPF_LD|BPF_IMM;
-                       s->k = -vmap[val[A_ATOM]].const_val;
+                       s->k = -opt_state->vmap[val[A_ATOM]].const_val;
                        val[A_ATOM] = K(s->k);
                }
                else
-                       val[A_ATOM] = F(s->code, val[A_ATOM], 0L);
+                       val[A_ATOM] = F(opt_state, s->code, val[A_ATOM], 0L);
                break;
 
        case BPF_ALU|BPF_ADD|BPF_K:
@@ -1026,13 +1031,13 @@ opt_stmt(struct stmt *s, int val[], int alter)
                                        break;
                                }
                        }
-                       if (vmap[val[A_ATOM]].is_const) {
-                               fold_op(s, val[A_ATOM], K(s->k));
+                       if (opt_state->vmap[val[A_ATOM]].is_const) {
+                               fold_op(cstate, ic, opt_state, s, val[A_ATOM], K(s->k));
                                val[A_ATOM] = K(s->k);
                                break;
                        }
                }
-               val[A_ATOM] = F(s->code, val[A_ATOM], K(s->k));
+               val[A_ATOM] = F(opt_state, s->code, val[A_ATOM], K(s->k));
                break;
 
        case BPF_ALU|BPF_ADD|BPF_X:
@@ -1046,17 +1051,17 @@ opt_stmt(struct stmt *s, int val[], int alter)
        case BPF_ALU|BPF_LSH|BPF_X:
        case BPF_ALU|BPF_RSH|BPF_X:
                op = BPF_OP(s->code);
-               if (alter && vmap[val[X_ATOM]].is_const) {
-                       if (vmap[val[A_ATOM]].is_const) {
-                               fold_op(s, val[A_ATOM], val[X_ATOM]);
+               if (alter && opt_state->vmap[val[X_ATOM]].is_const) {
+                       if (opt_state->vmap[val[A_ATOM]].is_const) {
+                               fold_op(cstate, ic, opt_state, s, val[A_ATOM], val[X_ATOM]);
                                val[A_ATOM] = K(s->k);
                        }
                        else {
                                s->code = BPF_ALU|BPF_K|op;
-                               s->k = vmap[val[X_ATOM]].const_val;
-                               done = 0;
+                               s->k = opt_state->vmap[val[X_ATOM]].const_val;
+                               opt_state->done = 0;
                                val[A_ATOM] =
-                                       F(s->code, val[A_ATOM], K(s->k));
+                                       F(opt_state, s->code, val[A_ATOM], K(s->k));
                        }
                        break;
                }
@@ -1067,8 +1072,8 @@ opt_stmt(struct stmt *s, int val[], int alter)
                 * optimizations.
                 * XXX We could also check for mul by 1, etc.
                 */
-               if (alter && vmap[val[A_ATOM]].is_const
-                   && vmap[val[A_ATOM]].const_val == 0) {
+               if (alter && opt_state->vmap[val[A_ATOM]].is_const
+                   && opt_state->vmap[val[A_ATOM]].const_val == 0) {
                        if (op == BPF_ADD || op == BPF_OR || op == BPF_XOR) {
                                s->code = BPF_MISC|BPF_TXA;
                                vstore(s, &val[A_ATOM], val[X_ATOM], alter);
@@ -1086,7 +1091,7 @@ opt_stmt(struct stmt *s, int val[], int alter)
                                break;
                        }
                }
-               val[A_ATOM] = F(s->code, val[A_ATOM], val[X_ATOM]);
+               val[A_ATOM] = F(opt_state, s->code, val[A_ATOM], val[X_ATOM]);
                break;
 
        case BPF_MISC|BPF_TXA:
@@ -1095,10 +1100,10 @@ opt_stmt(struct stmt *s, int val[], int alter)
 
        case BPF_LD|BPF_MEM:
                v = val[s->k];
-               if (alter && vmap[v].is_const) {
+               if (alter && opt_state->vmap[v].is_const) {
                        s->code = BPF_LD|BPF_IMM;
-                       s->k = vmap[v].const_val;
-                       done = 0;
+                       s->k = opt_state->vmap[v].const_val;
+                       opt_state->done = 0;
                }
                vstore(s, &val[A_ATOM], v, alter);
                break;
@@ -1109,10 +1114,10 @@ opt_stmt(struct stmt *s, int val[], int alter)
 
        case BPF_LDX|BPF_MEM:
                v = val[s->k];
-               if (alter && vmap[v].is_const) {
+               if (alter && opt_state->vmap[v].is_const) {
                        s->code = BPF_LDX|BPF_IMM;
-                       s->k = vmap[v].const_val;
-                       done = 0;
+                       s->k = opt_state->vmap[v].const_val;
+                       opt_state->done = 0;
                }
                vstore(s, &val[X_ATOM], v, alter);
                break;
@@ -1128,7 +1133,7 @@ opt_stmt(struct stmt *s, int val[], int alter)
 }
 
 static void
-deadstmt(register struct stmt *s, register struct stmt *last[])
+deadstmt(opt_state_t *opt_state, register struct stmt *s, register struct stmt *last[])
 {
        register int atom;
 
@@ -1144,7 +1149,7 @@ deadstmt(register struct stmt *s, register struct stmt *last[])
        atom = atomdef(s);
        if (atom >= 0) {
                if (last[atom]) {
-                       done = 0;
+                       opt_state->done = 0;
                        last[atom]->code = NOP;
                }
                last[atom] = s;
@@ -1152,7 +1157,7 @@ deadstmt(register struct stmt *s, register struct stmt *last[])
 }
 
 static void
-opt_deadstores(register struct block *b)
+opt_deadstores(opt_state_t *opt_state, register struct block *b)
 {
        register struct slist *s;
        register int atom;
@@ -1161,18 +1166,19 @@ opt_deadstores(register struct block *b)
        memset((char *)last, 0, sizeof last);
 
        for (s = b->stmts; s != 0; s = s->next)
-               deadstmt(&s->s, last);
-       deadstmt(&b->s, last);
+               deadstmt(opt_state, &s->s, last);
+       deadstmt(opt_state, &b->s, last);
 
        for (atom = 0; atom < N_ATOMS; ++atom)
                if (last[atom] && !ATOMELEM(b->out_use, atom)) {
                        last[atom]->code = NOP;
-                       done = 0;
+                       opt_state->done = 0;
                }
 }
 
 static void
-opt_blk(struct block *b, int do_stmts)
+opt_blk(compiler_state_t *cstate, struct icode *ic, opt_state_t *opt_state,
+    struct block *b, int do_stmts)
 {
        struct slist *s;
        struct edge *p;
@@ -1222,7 +1228,7 @@ opt_blk(struct block *b, int do_stmts)
        aval = b->val[A_ATOM];
        xval = b->val[X_ATOM];
        for (s = b->stmts; s; s = s->next)
-               opt_stmt(&s->s, b->val, do_stmts);
+               opt_stmt(cstate, ic, opt_state, &s->s, b->val, do_stmts);
 
        /*
         * This is a special case: if we don't use anything from this
@@ -1253,11 +1259,11 @@ opt_blk(struct block *b, int do_stmts)
             BPF_CLASS(b->s.code) == BPF_RET)) {
                if (b->stmts != 0) {
                        b->stmts = 0;
-                       done = 0;
+                       opt_state->done = 0;
                }
        } else {
-               opt_peep(b);
-               opt_deadstores(b);
+               opt_peep(opt_state, b);
+               opt_deadstores(opt_state, b);
        }
        /*
         * Set up values for branch optimizer.
@@ -1344,7 +1350,7 @@ fold_edge(struct block *child, struct edge *ep)
 }
 
 static void
-opt_j(struct edge *ep)
+opt_j(opt_state_t *opt_state, struct edge *ep)
 {
        register int i, k;
        register struct block *target;
@@ -1358,7 +1364,7 @@ opt_j(struct edge *ep)
                 * there is no data dependency.
                 */
                if (!use_conflict(ep->pred, ep->succ->et.succ)) {
-                       done = 0;
+                       opt_state->done = 0;
                        ep->succ = JT(ep->succ);
                }
        }
@@ -1370,7 +1376,7 @@ opt_j(struct edge *ep)
         * efficient loop.
         */
  top:
-       for (i = 0; i < edgewords; ++i) {
+       for (i = 0; i < opt_state->edgewords; ++i) {
                register bpf_u_int32 x = ep->edom[i];
 
                while (x != 0) {
@@ -1378,13 +1384,13 @@ opt_j(struct edge *ep)
                        x &=~ (1 << k);
                        k += i * BITS_PER_WORD;
 
-                       target = fold_edge(ep->succ, edges[k]);
+                       target = fold_edge(ep->succ, opt_state->edges[k]);
                        /*
                         * Check that there is no data dependency between
                         * nodes that will be violated if we move the edge.
                         */
                        if (target != 0 && !use_conflict(ep->pred, target)) {
-                               done = 0;
+                               opt_state->done = 0;
                                ep->succ = target;
                                if (JT(target) != 0)
                                        /*
@@ -1399,7 +1405,7 @@ opt_j(struct edge *ep)
 
 
 static void
-or_pullup(struct block *b)
+or_pullup(opt_state_t *opt_state, struct block *b)
 {
        int val, at_top;
        struct block *pull;
@@ -1487,11 +1493,11 @@ or_pullup(struct block *b)
        else
                *diffp = pull;
 
-       done = 0;
+       opt_state->done = 0;
 }
 
 static void
-and_pullup(struct block *b)
+and_pullup(opt_state_t *opt_state, struct block *b)
 {
        int val, at_top;
        struct block *pull;
@@ -1578,22 +1584,23 @@ and_pullup(struct block *b)
        else
                *diffp = pull;
 
-       done = 0;
+       opt_state->done = 0;
 }
 
 static void
-opt_blks(struct block *root, int do_stmts)
+opt_blks(compiler_state_t *cstate, opt_state_t *opt_state, struct icode *ic,
+    int do_stmts)
 {
        int i, maxlevel;
        struct block *p;
 
-       init_val();
-       maxlevel = root->level;
+       init_val(opt_state);
+       maxlevel = ic->root->level;
 
-       find_inedges(root);
+       find_inedges(opt_state, ic->root);
        for (i = maxlevel; i >= 0; --i)
-               for (p = levels[i]; p; p = p->link)
-                       opt_blk(p, do_stmts);
+               for (p = opt_state->levels[i]; p; p = p->link)
+                       opt_blk(cstate, ic, opt_state, p, do_stmts);
 
        if (do_stmts)
                /*
@@ -1603,17 +1610,17 @@ opt_blks(struct block *root, int do_stmts)
                return;
 
        for (i = 1; i <= maxlevel; ++i) {
-               for (p = levels[i]; p; p = p->link) {
-                       opt_j(&p->et);
-                       opt_j(&p->ef);
+               for (p = opt_state->levels[i]; p; p = p->link) {
+                       opt_j(opt_state, &p->et);
+                       opt_j(opt_state, &p->ef);
                }
        }
 
-       find_inedges(root);
+       find_inedges(opt_state, ic->root);
        for (i = 1; i <= maxlevel; ++i) {
-               for (p = levels[i]; p; p = p->link) {
-                       or_pullup(p);
-                       and_pullup(p);
+               for (p = opt_state->levels[i]; p; p = p->link) {
+                       or_pullup(opt_state, p);
+                       and_pullup(opt_state, p);
                }
        }
 }
@@ -1626,20 +1633,20 @@ link_inedge(struct edge *parent, struct block *child)
 }
 
 static void
-find_inedges(struct block *root)
+find_inedges(opt_state_t *opt_state, struct block *root)
 {
        int i;
        struct block *b;
 
-       for (i = 0; i < n_blocks; ++i)
-               blocks[i]->in_edges = 0;
+       for (i = 0; i < opt_state->n_blocks; ++i)
+               opt_state->blocks[i]->in_edges = 0;
 
        /*
         * Traverse the graph, adding each edge to the predecessor
         * list of its successors.  Skip the leaves (i.e. level 0).
         */
        for (i = root->level; i > 0; --i) {
-               for (b = levels[i]; b != 0; b = b->link) {
+               for (b = opt_state->levels[i]; b != 0; b = b->link) {
                        link_inedge(&b->et, JT(b));
                        link_inedge(&b->ef, JF(b));
                }
@@ -1671,83 +1678,82 @@ opt_root(struct block **b)
 }
 
 static void
-opt_loop(struct block *root, int do_stmts)
+opt_loop(compiler_state_t *cstate, opt_state_t *opt_state, struct icode *ic,
+    int do_stmts)
 {
 
 #ifdef BDEBUG
        if (pcap_optimizer_debug > 1) {
                printf("opt_loop(root, %d) begin\n", do_stmts);
-               opt_dump(root);
+               opt_dump(cstate, ic);
        }
 #endif
        do {
-               done = 1;
-               find_levels(root);
-               find_dom(root);
-               find_closure(root);
-               find_ud(root);
-               find_edom(root);
-               opt_blks(root, do_stmts);
+               opt_state->done = 1;
+               find_levels(opt_state, ic);
+               find_dom(opt_state, ic->root);
+               find_closure(opt_state, ic->root);
+               find_ud(opt_state, ic->root);
+               find_edom(opt_state, ic->root);
+               opt_blks(cstate, opt_state, ic, do_stmts);
 #ifdef BDEBUG
                if (pcap_optimizer_debug > 1) {
-                       printf("opt_loop(root, %d) bottom, done=%d\n", do_stmts, done);
-                       opt_dump(root);
+                       printf("opt_loop(root, %d) bottom, done=%d\n", do_stmts, opt_state->done);
+                       opt_dump(cstate, ic);
                }
 #endif
-       } while (!done);
+       } while (!opt_state->done);
 }
 
 /*
  * Optimize the filter code in its dag representation.
  */
 void
-bpf_optimize(struct block **rootp)
+bpf_optimize(compiler_state_t *cstate, struct icode *ic)
 {
-       struct block *root;
+       opt_state_t opt_state;
 
-       root = *rootp;
-
-       opt_init(root);
-       opt_loop(root, 0);
-       opt_loop(root, 1);
-       intern_blocks(root);
+       opt_init(cstate, &opt_state, ic);
+       opt_loop(cstate, &opt_state, ic, 0);
+       opt_loop(cstate, &opt_state, ic, 1);
+       intern_blocks(&opt_state, ic);
 #ifdef BDEBUG
        if (pcap_optimizer_debug > 1) {
                printf("after intern_blocks()\n");
-               opt_dump(root);
+               opt_dump(cstate, ic);
        }
 #endif
-       opt_root(rootp);
+       opt_root(&ic->root);
 #ifdef BDEBUG
        if (pcap_optimizer_debug > 1) {
                printf("after opt_root()\n");
-               opt_dump(root);
+               opt_dump(cstate, ic);
        }
 #endif
-       opt_cleanup();
+       opt_cleanup(&opt_state);
 }
 
 static void
-make_marks(struct block *p)
+make_marks(struct icode *ic, struct block *p)
 {
-       if (!isMarked(p)) {
-               Mark(p);
+       if (!isMarked(ic, p)) {
+               Mark(ic, p);
                if (BPF_CLASS(p->s.code) != BPF_RET) {
-                       make_marks(JT(p));
-                       make_marks(JF(p));
+                       make_marks(ic, JT(p));
+                       make_marks(ic, JF(p));
                }
        }
 }
 
 /*
- * Mark code array such that isMarked(i) is true
+ * Mark code array such that isMarked(ic->cur_mark, i) is true
  * only for nodes that are alive.
  */
 static void
-mark_code(struct block *p)
+mark_code(struct icode *ic)
 {
-       cur_mark += 1;
-       make_marks(p);
+       ic->cur_mark += 1;
+       make_marks(ic, ic->root);
 }
 
 /*
@@ -1785,33 +1791,33 @@ eq_blk(struct block *b0, struct block *b1)
 }
 
 static void
-intern_blocks(struct block *root)
+intern_blocks(opt_state_t *opt_state, struct icode *ic)
 {
        struct block *p;
        int i, j;
        int done1; /* don't shadow global */
  top:
        done1 = 1;
-       for (i = 0; i < n_blocks; ++i)
-               blocks[i]->link = 0;
+       for (i = 0; i < opt_state->n_blocks; ++i)
+               opt_state->blocks[i]->link = 0;
 
-       mark_code(root);
+       mark_code(ic);
 
-       for (i = n_blocks - 1; --i >= 0; ) {
-               if (!isMarked(blocks[i]))
+       for (i = opt_state->n_blocks - 1; --i >= 0; ) {
+               if (!isMarked(ic, opt_state->blocks[i]))
                        continue;
-               for (j = i + 1; j < n_blocks; ++j) {
-                       if (!isMarked(blocks[j]))
+               for (j = i + 1; j < opt_state->n_blocks; ++j) {
+                       if (!isMarked(ic, opt_state->blocks[j]))
                                continue;
-                       if (eq_blk(blocks[i], blocks[j])) {
-                               blocks[i]->link = blocks[j]->link ?
-                                       blocks[j]->link : blocks[j];
+                       if (eq_blk(opt_state->blocks[i], opt_state->blocks[j])) {
+                               opt_state->blocks[i]->link = opt_state->blocks[j]->link ?
+                                       opt_state->blocks[j]->link : opt_state->blocks[j];
                                break;
                        }
                }
        }
-       for (i = 0; i < n_blocks; ++i) {
-               p = blocks[i];
+       for (i = 0; i < opt_state->n_blocks; ++i) {
+               p = opt_state->blocks[i];
                if (JT(p) == 0)
                        continue;
                if (JT(p)->link) {
@@ -1828,14 +1834,14 @@ intern_blocks(struct block *root)
 }
 
 static void
-opt_cleanup(void)
+opt_cleanup(opt_state_t *opt_state)
 {
-       free((void *)vnode_base);
-       free((void *)vmap);
-       free((void *)edges);
-       free((void *)space);
-       free((void *)levels);
-       free((void *)blocks);
+       free((void *)opt_state->vnode_base);
+       free((void *)opt_state->vmap);
+       free((void *)opt_state->edges);
+       free((void *)opt_state->space);
+       free((void *)opt_state->levels);
+       free((void *)opt_state->blocks);
 }
 
 /*
@@ -1857,12 +1863,12 @@ slength(struct slist *s)
  * All nodes should be initially unmarked.
  */
 static int
-count_blocks(struct block *p)
+count_blocks(struct icode *ic, struct block *p)
 {
-       if (p == 0 || isMarked(p))
+       if (p == 0 || isMarked(ic, p))
                return 0;
-       Mark(p);
-       return count_blocks(JT(p)) + count_blocks(JF(p)) + 1;
+       Mark(ic, p);
+       return count_blocks(ic, JT(p)) + count_blocks(ic, JF(p)) + 1;
 }
 
 /*
@@ -1870,20 +1876,20 @@ count_blocks(struct block *p)
  * the basic blocks, and entering them into the 'blocks' array.`
  */
 static void
-number_blks_r(struct block *p)
+number_blks_r(opt_state_t *opt_state, struct icode *ic, struct block *p)
 {
        int n;
 
-       if (p == 0 || isMarked(p))
+       if (p == 0 || isMarked(ic, p))
                return;
 
-       Mark(p);
-       n = n_blocks++;
+       Mark(ic, p);
+       n = opt_state->n_blocks++;
        p->id = n;
-       blocks[n] = p;
+       opt_state->blocks[n] = p;
 
-       number_blks_r(JT(p));
-       number_blks_r(JF(p));
+       number_blks_r(opt_state, ic, JT(p));
+       number_blks_r(opt_state, ic, JF(p));
 }
 
 /*
@@ -1905,14 +1911,14 @@ number_blks_r(struct block *p)
  *     an extra long jump if the false branch requires it (p->longjf).
  */
 static u_int
-count_stmts(struct block *p)
+count_stmts(struct icode *ic, struct block *p)
 {
        u_int n;
 
-       if (p == 0 || isMarked(p))
+       if (p == 0 || isMarked(ic, p))
                return 0;
-       Mark(p);
-       n = count_stmts(JT(p)) + count_stmts(JF(p));
+       Mark(ic, p);
+       n = count_stmts(ic, JT(p)) + count_stmts(ic, JF(p));
        return slength(p->stmts) + n + 1 + p->longjt + p->longjf;
 }
 
@@ -1922,7 +1928,7 @@ count_stmts(struct block *p)
  * from the total number of blocks and/or statements.
  */
 static void
-opt_init(struct block *root)
+opt_init(compiler_state_t *cstate, opt_state_t *opt_state, struct icode *ic)
 {
        bpf_u_int32 *p;
        int i, n, max_stmts;
@@ -1931,84 +1937,81 @@ opt_init(struct block *root)
         * First, count the blocks, so we can malloc an array to map
         * block number to block.  Then, put the blocks into the array.
         */
-       unMarkAll();
-       n = count_blocks(root);
-       blocks = (struct block **)calloc(n, sizeof(*blocks));
-       if (blocks == NULL)
-               bpf_error("malloc");
-       unMarkAll();
-       n_blocks = 0;
-       number_blks_r(root);
-
-       n_edges = 2 * n_blocks;
-       edges = (struct edge **)calloc(n_edges, sizeof(*edges));
-       if (edges == NULL)
-               bpf_error("malloc");
+       unMarkAll(ic);
+       n = count_blocks(ic, ic->root);
+       opt_state->blocks = (struct block **)calloc(n, sizeof(*opt_state->blocks));
+       if (opt_state->blocks == NULL)
+               bpf_error(cstate, "malloc");
+       unMarkAll(ic);
+       opt_state->n_blocks = 0;
+       number_blks_r(opt_state, ic, ic->root);
+
+       opt_state->n_edges = 2 * opt_state->n_blocks;
+       opt_state->edges = (struct edge **)calloc(opt_state->n_edges, sizeof(*opt_state->edges));
+       if (opt_state->edges == NULL)
+               bpf_error(cstate, "malloc");
 
        /*
         * The number of levels is bounded by the number of nodes.
         */
-       levels = (struct block **)calloc(n_blocks, sizeof(*levels));
-       if (levels == NULL)
-               bpf_error("malloc");
+       opt_state->levels = (struct block **)calloc(opt_state->n_blocks, sizeof(*opt_state->levels));
+       if (opt_state->levels == NULL)
+               bpf_error(cstate, "malloc");
 
-       edgewords = n_edges / (8 * sizeof(bpf_u_int32)) + 1;
-       nodewords = n_blocks / (8 * sizeof(bpf_u_int32)) + 1;
+       opt_state->edgewords = opt_state->n_edges / (8 * sizeof(bpf_u_int32)) + 1;
+       opt_state->nodewords = opt_state->n_blocks / (8 * sizeof(bpf_u_int32)) + 1;
 
        /* XXX */
-       space = (bpf_u_int32 *)malloc(2 * n_blocks * nodewords * sizeof(*space)
-                                + n_edges * edgewords * sizeof(*space));
-       if (space == NULL)
-               bpf_error("malloc");
-       p = space;
-       all_dom_sets = p;
+       opt_state->space = (bpf_u_int32 *)malloc(2 * opt_state->n_blocks * opt_state->nodewords * sizeof(*opt_state->space)
+                                + opt_state->n_edges * opt_state->edgewords * sizeof(*opt_state->space));
+       if (opt_state->space == NULL)
+               bpf_error(cstate, "malloc");
+       p = opt_state->space;
+       opt_state->all_dom_sets = p;
        for (i = 0; i < n; ++i) {
-               blocks[i]->dom = p;
-               p += nodewords;
+               opt_state->blocks[i]->dom = p;
+               p += opt_state->nodewords;
        }
-       all_closure_sets = p;
+       opt_state->all_closure_sets = p;
        for (i = 0; i < n; ++i) {
-               blocks[i]->closure = p;
-               p += nodewords;
+               opt_state->blocks[i]->closure = p;
+               p += opt_state->nodewords;
        }
-       all_edge_sets = p;
+       opt_state->all_edge_sets = p;
        for (i = 0; i < n; ++i) {
-               register struct block *b = blocks[i];
+               register struct block *b = opt_state->blocks[i];
 
                b->et.edom = p;
-               p += edgewords;
+               p += opt_state->edgewords;
                b->ef.edom = p;
-               p += edgewords;
+               p += opt_state->edgewords;
                b->et.id = i;
-               edges[i] = &b->et;
-               b->ef.id = n_blocks + i;
-               edges[n_blocks + i] = &b->ef;
+               opt_state->edges[i] = &b->et;
+               b->ef.id = opt_state->n_blocks + i;
+               opt_state->edges[opt_state->n_blocks + i] = &b->ef;
                b->et.pred = b;
                b->ef.pred = b;
        }
        max_stmts = 0;
        for (i = 0; i < n; ++i)
-               max_stmts += slength(blocks[i]->stmts) + 1;
+               max_stmts += slength(opt_state->blocks[i]->stmts) + 1;
        /*
         * We allocate at most 3 value numbers per statement,
         * so this is an upper bound on the number of valnodes
         * we'll need.
         */
-       maxval = 3 * max_stmts;
-       vmap = (struct vmapinfo *)calloc(maxval, sizeof(*vmap));
-       vnode_base = (struct valnode *)calloc(maxval, sizeof(*vnode_base));
-       if (vmap == NULL || vnode_base == NULL)
-               bpf_error("malloc");
+       opt_state->maxval = 3 * max_stmts;
+       opt_state->vmap = (struct vmapinfo *)calloc(opt_state->maxval, sizeof(*opt_state->vmap));
+       opt_state->vnode_base = (struct valnode *)calloc(opt_state->maxval, sizeof(*opt_state->vnode_base));
+       if (opt_state->vmap == NULL || opt_state->vnode_base == NULL)
+               bpf_error(cstate, "malloc");
 }
 
 /*
- * Some pointers used to convert the basic block form of the code,
- * into the array form that BPF requires.  'fstart' will point to
- * the malloc'd array while 'ftail' is used during the recursive traversal.
+ * This is only used when supporting optimizer debugging.  It is
+ * global state, so do *not* do more than one compile in parallel
+ * and expect it to provide meaningful information.
  */
-static struct bpf_insn *fstart;
-static struct bpf_insn *ftail;
-
 #ifdef BDEBUG
 int bids[1000];
 #endif
@@ -2020,7 +2023,8 @@ int bids[1000];
  * properly.
  */
 static int
-convert_code_r(struct block *p)
+convert_code_r(compiler_state_t *cstate, conv_state_t *conv_state,
+    struct icode *ic, struct block *p)
 {
        struct bpf_insn *dst;
        struct slist *src;
@@ -2029,26 +2033,26 @@ convert_code_r(struct block *p)
        int extrajmps;          /* number of extra jumps inserted */
        struct slist **offset = NULL;
 
-       if (p == 0 || isMarked(p))
+       if (p == 0 || isMarked(ic, p))
                return (1);
-       Mark(p);
+       Mark(ic, p);
 
-       if (convert_code_r(JF(p)) == 0)
+       if (convert_code_r(cstate, conv_state, ic, JF(p)) == 0)
                return (0);
-       if (convert_code_r(JT(p)) == 0)
+       if (convert_code_r(cstate, conv_state, ic, JT(p)) == 0)
                return (0);
 
        slen = slength(p->stmts);
-       dst = ftail -= (slen + 1 + p->longjt + p->longjf);
+       dst = conv_state->ftail -= (slen + 1 + p->longjt + p->longjf);
                /* inflate length by any extra jumps */
 
-       p->offset = dst - fstart;
+       p->offset = dst - conv_state->fstart;
 
        /* generate offset[] for convenience  */
        if (slen) {
                offset = (struct slist **)calloc(slen, sizeof(struct slist *));
                if (!offset) {
-                       bpf_error("not enough core");
+                       bpf_error(cstate, "not enough core");
                        /*NOTREACHED*/
                }
        }
@@ -2072,7 +2076,7 @@ convert_code_r(struct block *p)
                if (BPF_CLASS(src->s.code) != BPF_JMP || src->s.code == (BPF_JMP|BPF_JA)) {
 #if 0
                        if (src->s.jt || src->s.jf) {
-                               bpf_error("illegal jmp destination");
+                               bpf_error(cstate, "illegal jmp destination");
                                /*NOTREACHED*/
                        }
 #endif
@@ -2092,7 +2096,7 @@ convert_code_r(struct block *p)
 #endif
 
                if (!src->s.jt || !src->s.jf) {
-                       bpf_error(ljerr, "no jmp destination", off);
+                       bpf_error(cstate, ljerr, "no jmp destination", off);
                        /*NOTREACHED*/
                }
 
@@ -2100,7 +2104,7 @@ convert_code_r(struct block *p)
                for (i = 0; i < slen; i++) {
                        if (offset[i] == src->s.jt) {
                                if (jt) {
-                                       bpf_error(ljerr, "multiple matches", off);
+                                       bpf_error(cstate, ljerr, "multiple matches", off);
                                        /*NOTREACHED*/
                                }
 
@@ -2109,7 +2113,7 @@ convert_code_r(struct block *p)
                        }
                        if (offset[i] == src->s.jf) {
                                if (jf) {
-                                       bpf_error(ljerr, "multiple matches", off);
+                                       bpf_error(cstate, ljerr, "multiple matches", off);
                                        /*NOTREACHED*/
                                }
                                dst->jf = i - off - 1;
@@ -2117,7 +2121,7 @@ convert_code_r(struct block *p)
                        }
                }
                if (!jt || !jf) {
-                       bpf_error(ljerr, "no destination found", off);
+                       bpf_error(cstate, ljerr, "no destination found", off);
                        /*NOTREACHED*/
                }
            }
@@ -2129,7 +2133,7 @@ filled:
                free(offset);
 
 #ifdef BDEBUG
-       bids[dst - fstart] = p->id + 1;
+       bids[dst - conv_state->fstart] = p->id + 1;
 #endif
        dst->code = (u_short)p->s.code;
        dst->k = p->s.k;
@@ -2192,28 +2196,30 @@ filled:
  * done with the filter program.  See the pcap man page.
  */
 struct bpf_insn *
-icode_to_fcode(struct block *root, u_int *lenp)
+icode_to_fcode(compiler_state_t *cstate, struct icode *ic,
+    struct block *root, u_int *lenp)
 {
        u_int n;
        struct bpf_insn *fp;
+       conv_state_t conv_state;
 
        /*
         * Loop doing convert_code_r() until no branches remain
         * with too-large offsets.
         */
        while (1) {
-           unMarkAll();
-           n = *lenp = count_stmts(root);
+           unMarkAll(ic);
+           n = *lenp = count_stmts(ic, root);
 
            fp = (struct bpf_insn *)malloc(sizeof(*fp) * n);
            if (fp == NULL)
-                   bpf_error("malloc");
+                   bpf_error(cstate, "malloc");
            memset((char *)fp, 0, sizeof(*fp) * n);
-           fstart = fp;
-           ftail = fp + n;
+           conv_state.fstart = fp;
+           conv_state.ftail = fp + n;
 
-           unMarkAll();
-           if (convert_code_r(root))
+           unMarkAll(ic);
+           if (convert_code_r(cstate, &conv_state, ic, root))
                break;
            free(fp);
        }
@@ -2262,14 +2268,15 @@ install_bpf_program(pcap_t *p, struct bpf_program *fp)
 
 #ifdef BDEBUG
 static void
-dot_dump_node(struct block *block, struct bpf_program *prog, FILE *out)
+dot_dump_node(struct icode *ic, struct block *block, struct bpf_program *prog,
+    FILE *out)
 {
        int icount, noffset;
        int i;
 
-       if (block == NULL || isMarked(block))
+       if (block == NULL || isMarked(ic, block))
                return;
-       Mark(block);
+       Mark(ic, block);
 
        icount = slength(block->stmts) + 1 + block->longjt + block->longjf;
        noffset = min(block->offset + icount, (int)prog->bf_len);
@@ -2289,16 +2296,16 @@ dot_dump_node(struct block *block, struct bpf_program *prog, FILE *out)
                fprintf(out, ", peripheries=2");
        fprintf(out, "];\n");
 
-       dot_dump_node(JT(block), prog, out);
-       dot_dump_node(JF(block), prog, out);
+       dot_dump_node(ic, JT(block), prog, out);
+       dot_dump_node(ic, JF(block), prog, out);
 }
 
 static void
-dot_dump_edge(struct block *block, FILE *out)
+dot_dump_edge(struct icode *ic, struct block *block, FILE *out)
 {
-       if (block == NULL || isMarked(block))
+       if (block == NULL || isMarked(ic, block))
                return;
-       Mark(block);
+       Mark(ic, block);
 
        if (JT(block)) {
                fprintf(out, "\t\"block%d\":se -> \"block%d\":n [label=\"T\"]; \n",
@@ -2306,8 +2313,8 @@ dot_dump_edge(struct block *block, FILE *out)
                fprintf(out, "\t\"block%d\":sw -> \"block%d\":n [label=\"F\"]; \n",
                           block->id, JF(block)->id);
        }
-       dot_dump_edge(JT(block), out);
-       dot_dump_edge(JF(block), out);
+       dot_dump_edge(ic, JT(block), out);
+       dot_dump_edge(ic, JF(block), out);
 }
 
 /* Output the block CFG using graphviz/DOT language
@@ -2330,46 +2337,48 @@ dot_dump_edge(struct block *block, FILE *out)
  *  and run `dot -Tpng -O bpf.dot' to draw the graph.
  */
 static void
-dot_dump(struct block *root)
+dot_dump(compiler_state_t *cstate, struct icode *ic)
 {
        struct bpf_program f;
        FILE *out = stdout;
 
        memset(bids, 0, sizeof bids);
-       f.bf_insns = icode_to_fcode(root, &f.bf_len);
+       f.bf_insns = icode_to_fcode(cstate, ic, ic->root, &f.bf_len);
 
        fprintf(out, "digraph BPF {\n");
-       unMarkAll();
-       dot_dump_node(root, &f, out);
-       unMarkAll();
-       dot_dump_edge(root, out);
+       ic->cur_mark = 0;
+       unMarkAll(ic);
+       dot_dump_node(ic, ic->root, &f, out);
+       ic->cur_mark = 0;
+       unMarkAll(ic);
+       dot_dump_edge(ic, ic->root, out);
        fprintf(out, "}\n");
 
        free((char *)f.bf_insns);
 }
 
 static void
-plain_dump(struct block *root)
+plain_dump(compiler_state_t *cstate, struct icode *ic)
 {
        struct bpf_program f;
 
        memset(bids, 0, sizeof bids);
-       f.bf_insns = icode_to_fcode(root, &f.bf_len);
+       f.bf_insns = icode_to_fcode(cstate, ic, ic->root, &f.bf_len);
        bpf_dump(&f, 1);
        putchar('\n');
        free((char *)f.bf_insns);
 }
 
 static void
-opt_dump(struct block *root)
+opt_dump(compiler_state_t *cstate, struct icode *ic)
 {
        /* if optimizer debugging is enabled, output DOT graph
         * `pcap_optimizer_debug=4' is equivalent to -dddd to follow -d/-dd/-ddd
         * convention in tcpdump command line
         */
        if (pcap_optimizer_debug > 3)
-               dot_dump(root);
+               dot_dump(cstate, ic);
        else
-               plain_dump(root);
+               plain_dump(cstate, ic);
 }
 #endif
index a2a15463a7c69410a642a2b1eb70df9bc092f427..f855386fde0351eb9cebe46417e444d05233afc5 100644 (file)
@@ -47,7 +47,6 @@ extern "C" {
    */
   #define BPF_MAJOR_VERSION
   #include <Packet32.h>
-  extern CRITICAL_SECTION g_PcapCompileCriticalSection;
 #elif defined(MSDOS)
   #include <fcntl.h>
   #include <io.h>
index d63b83c9894ffc057341d18e34a2ea047a692fd1..a6a57a3e84e1e5ed01cde6f83783ea28f0465ebf 100644 (file)
@@ -81,19 +81,12 @@ struct pcap_win {
 #endif
 };
 
-CRITICAL_SECTION g_PcapCompileCriticalSection;
-
 BOOL WINAPI DllMain(
   HANDLE hinstDLL,
   DWORD dwReason,
   LPVOID lpvReserved
 )
 {
-       if (dwReason == DLL_PROCESS_ATTACH)
-       {
-               InitializeCriticalSection(&g_PcapCompileCriticalSection);
-       }
-
        return (TRUE);
 }
 
@@ -112,7 +105,6 @@ wsockinit(void)
        wVersionRequested = MAKEWORD( 1, 1);
        err = WSAStartup( wVersionRequested, &wsaData );
        atexit ((void(*)(void))WSACleanup);
-       InitializeCriticalSection(&g_PcapCompileCriticalSection);
        done = 1;
 
        if ( err != 0 )
index 3dbe0367be60e0b7862bb5d627002f07b257f29a..1000b7a3c903e588a76c76205083285e3edb2e5c 100644 (file)
--- a/scanner.l
+++ b/scanner.l
  */
 %option reentrant
 
+/*
+ * And we need to pass the compiler state to the scanner.
+ */
+%option extra-type="compiler_state_t *"
+
 /*
  * We don't use input, so don't generate code for it.
  */
@@ -294,7 +299,7 @@ portrange   return PORTRANGE;
 proto          return PROTO;
 protochain     {
 #ifdef NO_PROTOCHAIN
-                 bpf_error("%s not supported", yytext);
+                 bpf_error(yyextra, "%s not supported", yytext);
 #else
                  return PROTOCHAIN;
 #endif
@@ -380,15 +385,15 @@ hsls              return HSLS;
 ">>"                   return RSH;
 ${B}                   { yylval->e = pcap_ether_aton(((char *)yytext)+1);
                          if (yylval->e == NULL)
-                               bpf_error("malloc");
+                               bpf_error(yyextra, "malloc");
                          return AID; }
 {MAC}                  { yylval->e = pcap_ether_aton((char *)yytext);
                          if (yylval->e == NULL)
-                               bpf_error("malloc");
+                               bpf_error(yyextra, "malloc");
                          return EID; }
 {N}                    { yylval->i = stoi((char *)yytext); return NUM; }
 ({N}\.{N})|({N}\.{N}\.{N})|({N}\.{N}\.{N}\.{N})        {
-                       yylval->s = sdup((char *)yytext); return HID; }
+                       yylval->s = sdup(yyextra, (char *)yytext); return HID; }
 {V6}                   {
 #ifdef INET6
                          struct addrinfo hints, *res;
@@ -396,16 +401,16 @@ ${B}                      { yylval->e = pcap_ether_aton(((char *)yytext)+1);
                          hints.ai_family = AF_INET6;
                          hints.ai_flags = AI_NUMERICHOST;
                          if (getaddrinfo(yytext, NULL, &hints, &res))
-                               bpf_error("bogus IPv6 address %s", yytext);
+                               bpf_error(yyextra, "bogus IPv6 address %s", yytext);
                          else {
                                freeaddrinfo(res);
-                               yylval->s = sdup((char *)yytext); return HID6;
+                               yylval->s = sdup(yyextra, (char *)yytext); return HID6;
                          }
 #else
-                         bpf_error("IPv6 address %s not supported", yytext);
+                         bpf_error(yyextra, "IPv6 address %s not supported", yytext);
 #endif /*INET6*/
                        }
-{B}:+({B}:+)+          { bpf_error("bogus ethernet address %s", yytext); }
+{B}:+({B}:+)+          { bpf_error(yyextra, "bogus ethernet address %s", yytext); }
 icmptype               { yylval->i = 0; return NUM; }
 icmpcode               { yylval->i = 1; return NUM; }
 icmp-echoreply         { yylval->i = 0; return NUM; }
@@ -431,11 +436,11 @@ tcp-push          { yylval->i = 0x08; return NUM; }
 tcp-ack                        { yylval->i = 0x10; return NUM; }
 tcp-urg                        { yylval->i = 0x20; return NUM; }
 [A-Za-z0-9]([-_.A-Za-z0-9]*[.A-Za-z0-9])? {
-                        yylval->s = sdup((char *)yytext); return ID; }
-"\\"[^ !()\n\t]+       { yylval->s = sdup((char *)yytext + 1); return ID; }
+                        yylval->s = sdup(yyextra, (char *)yytext); return ID; }
+"\\"[^ !()\n\t]+       { yylval->s = sdup(yyextra, (char *)yytext + 1); return ID; }
 [^ \[\]\t\n\-_.A-Za-z0-9!<>()&|=]+ {
-                       bpf_error("illegal token: %s", yytext); }
-.                      { bpf_error("illegal char '%c'", *yytext); }
+                       bpf_error(yyextra, "illegal token: %s", yytext); }
+.                      { bpf_error(yyextra, "illegal char '%c'", *yytext); }
 %%
 
 /* Hex digit to integer. */