Rollup merge of #153015 - joboet:atomic_alias_generic, r=jhpratt

core: make atomic primitives type aliases of `Atomic<T>`

Tracking issue: #130539

This makes `AtomicI32` and friends type aliases of `Atomic<T>` by encoding their alignment requirements via the use of an internal `Storage` associated type. This is also used to encode that `AtomicBool` store a `u8` internally.

Modulo the `Send`/`Sync` implementations, this PR does not move any trait implementations, methods or associated functions – I'll leave that for another PR.

Author: JonathanBrouwer

compiler/rustc_data_structures/src/marker.rs

@@ -59,11 +59,16 @@ macro_rules! already_send {
 
 // These structures are already `Send`.
 already_send!(
-    [std::backtrace::Backtrace][std::io::Stdout][std::io::Stderr][std::io::Error][std::fs::File][std::panic::Location<'_>]
-        [rustc_arena::DroplessArena][jobserver_crate::Client][jobserver_crate::HelperThread]
-        [crate::memmap::Mmap][crate::profiling::SelfProfiler][crate::owned_slice::OwnedSlice]
+    [std::sync::atomic::AtomicBool][std::sync::atomic::AtomicUsize][std::sync::atomic::AtomicU8]
+        [std::sync::atomic::AtomicU32][std::backtrace::Backtrace][std::io::Stdout][std::io::Stderr]
+        [std::io::Error][std::fs::File][std::panic::Location<'_>][rustc_arena::DroplessArena]
+        [jobserver_crate::Client][jobserver_crate::HelperThread][crate::memmap::Mmap]
+        [crate::profiling::SelfProfiler][crate::owned_slice::OwnedSlice]
 );
 
+#[cfg(target_has_atomic = "64")]
+already_send!([std::sync::atomic::AtomicU64]);
+
 macro_rules! impl_dyn_send {
     ($($($attr: meta)* [$ty: ty where $($generics2: tt)*])*) => {
         $(unsafe impl<$($generics2)*> DynSend for $ty {})*

compiler/rustc_lint/src/types.rs

@@ -1036,31 +1036,13 @@ impl InvalidAtomicOrdering {
         expr: &Expr<'hir>,
         recognized_names: &[Symbol], // used for fast path calculation
     ) -> Option<(Symbol, &'hir [Expr<'hir>])> {
-        const ATOMIC_TYPES: &[Symbol] = &[
-            sym::AtomicBool,
-            sym::AtomicPtr,
-            sym::AtomicUsize,
-            sym::AtomicU8,
-            sym::AtomicU16,
-            sym::AtomicU32,
-            sym::AtomicU64,
-            sym::AtomicU128,
-            sym::AtomicIsize,
-            sym::AtomicI8,
-            sym::AtomicI16,
-            sym::AtomicI32,
-            sym::AtomicI64,
-            sym::AtomicI128,
-        ];
         if let ExprKind::MethodCall(method_path, _, args, _) = &expr.kind
             && recognized_names.contains(&method_path.ident.name)
             && let Some(m_def_id) = cx.typeck_results().type_dependent_def_id(expr.hir_id)
             // skip extension traits, only lint functions from the standard library
             && let Some(impl_did) = cx.tcx.inherent_impl_of_assoc(m_def_id)
             && let Some(adt) = cx.tcx.type_of(impl_did).instantiate_identity().ty_adt_def()
-            && let parent = cx.tcx.parent(adt.did())
-            && cx.tcx.is_diagnostic_item(sym::atomic_mod, parent)
-            && ATOMIC_TYPES.contains(&cx.tcx.item_name(adt.did()))
+            && cx.tcx.is_diagnostic_item(sym::Atomic, adt.did())
         {
             return Some((method_path.ident.name, args));
         }

compiler/rustc_span/src/symbol.rs

@@ -171,20 +171,7 @@ symbols! {
         AsyncGenFinished,
         AsyncGenPending,
         AsyncGenReady,
-        AtomicBool,
-        AtomicI8,
-        AtomicI16,
-        AtomicI32,
-        AtomicI64,
-        AtomicI128,
-        AtomicIsize,
-        AtomicPtr,
-        AtomicU8,
-        AtomicU16,
-        AtomicU32,
-        AtomicU64,
-        AtomicU128,
-        AtomicUsize,
+        Atomic,
         BTreeMap,
         Bool,
         Borrow,
@@ -485,7 +472,6 @@ symbols! {
         atomic_load,
         atomic_max,
         atomic_min,
-        atomic_mod,
         atomic_nand,
         atomic_or,
         atomic_singlethreadfence,