[clang] [Clang] Introduce scoped variants of GNU atomic functions (PR #72280)

[Matt Arsenault via cfe-commits]

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@@ -904,6 +904,32 @@ BUILTIN(__atomic_signal_fence, "vi", "n")
 BUILTIN(__atomic_always_lock_free, "bzvCD*", "nE")
 BUILTIN(__atomic_is_lock_free, "bzvCD*", "nE")
 
+// GNU atomic builtins with atomic scopes.
+ATOMIC_BUILTIN(__scoped_atomic_load, "v.", "t")
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arsenm wrote:

I wonder if it would be better to preserve __atomic as the prefix, and move the _scope part to the name suffix 

https://github.com/llvm/llvm-project/pull/72280