[llvm] [Transforms] Introduce BuildBuiltins.h atomic helpers (PR #134455)

[via llvm-commits]

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@@ -462,11 +462,91 @@ TLI_DEFINE_ENUM_INTERNAL(atomic_load)
 TLI_DEFINE_STRING_INTERNAL("__atomic_load")
 TLI_DEFINE_SIG_INTERNAL(Void, SizeT, Ptr, Ptr, Int)
 
+/// int8_t __atomic_load_1(void *ptr, int memorder);
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NimishMishra wrote:

Is the choice to let `__atomic_load_N` return a sized integer, while `__atomic_load` return void based on maintaining proximity with GCC's definitions of these builtins? Or is there any other reason which I am missing?

https://github.com/llvm/llvm-project/pull/134455