[clang] [llvm] [AArch64] Implement the atomic store with hint intrinsic (PR #198316)

[via cfe-commits]

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@@ -157,6 +157,13 @@ static bool mayPrefetch(const MCInst &Inst) {
   }
 }
 
+// Memory hints 48 (stshh keep) & 49 (stshh strm) should be emitted
+// immediately before a store instruction.
+static bool isMemHint(const MCInst &Inst) {
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Lukacma wrote:

I meant this in context of C tests. Sometimes you use __builtin_arm_atomic_store_with_hint in them instead of __arm_atomic_store_with_hint, but looking at it again it is just define macro so it is fine to leave it as it is. 

https://github.com/llvm/llvm-project/pull/198316