Expand some comments.

diff --git a/optimize.c b/optimize.c
index ccb4ab8ed6476646db3d349d1b060d0ef611b1c0..f80a75ff37af8c9f9961613bb1138999b6ea6d36 100644 (file)
--- a/optimize.c
+++ b/optimize.c
@@ -22,7 +22,7 @@
  */
 #ifndef lint
 static const char rcsid[] _U_ =
-    "@(#) $Header: /tcpdump/master/libpcap/optimize.c,v 1.82 2004-11-14 00:28:18 guy Exp $ (LBL)";
+    "@(#) $Header: /tcpdump/master/libpcap/optimize.c,v 1.83 2004-11-14 03:10:33 guy Exp $ (LBL)";
 #endif
 
 #ifdef HAVE_CONFIG_H
@@ -1206,11 +1206,18 @@ opt_blk(b, do_stmts)
        } else {
                /*
                 * Inherit values from our predecessors.
+                *
+                * First, get the values from the predecessor along the
+                * first edge leading to this node.
                 */
                memcpy((char *)b->val, (char *)p->pred->val, sizeof(b->val));
                /*
-                * If any register has an ambiguous value (i.e., control
-                * paths are merging), give it the undefined value of 0.
+                * Now look at all the other nodes leading to this node.
+                * If, for the predecessor along that edge, a register
+                * has a different value from the one we have (i.e.,
+                * control paths are merging, and the merging paths
+                * assign different values to that register), give the
+                * register the undefined value of 0.
                 */
                while ((p = p->next) != NULL) {
                        for (i = 0; i < N_ATOMS; ++i)