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

[Pierre van Houtryve 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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Pierre-vh wrote:

Just remove `m_amdgpu_Features_Group` from your option's `SimpleMFlag`, follow the same pattern as `wavefrontsize64`

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