[clang] [llvm] [AArch64] Implement the atomic fetch with hint intrinsic (PR #227711)

[Kerry McLaughlin via cfe-commits]

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@@ -14,11 +14,14 @@ enum class AArch64MemoryHint {
   NONE = 0,
   STSHH_KEEP = 1,
   STSHH_STRM = 2,
+  STCPH = 3,
+  SHUH = 4,
+  SHUH_PH = 5,
 };
 
 template <typename Int> inline bool isValidAArch64MemoryHintValue(Int I) {
   return (Int)AArch64MemoryHint::STSHH_KEEP <= I &&
-         I <= (Int)AArch64MemoryHint::STSHH_STRM;
+         I <= (Int)AArch64MemoryHint::SHUH_PH;
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kmclaughlin-arm wrote:

I realise that I added this function, but I don't think it's being used anywhere anymore. Maybe it's best to just remove it for now?

https://github.com/llvm/llvm-project/pull/227711