[clang] [llvm] [AMDGPU] Emit a waitcnt instruction after each memory instruction (PR #79236)

[Matt Arsenault via cfe-commits]

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@@ -167,6 +167,10 @@ def FeatureCuMode : SubtargetFeature<"cumode",
   "Enable CU wavefront execution mode"
 >;
 
+def FeaturePreciseMemory
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arsenm wrote:

The subtarget feature prefix should be removed. The subtarget feature name is not the user facing component of this, and no user should be directly using it 

https://github.com/llvm/llvm-project/pull/79236