[llvm] [clang] [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:

Understood :) 
Can you remove the `amdgpu` prefix from the option? All target features are already specific to AMDGPU, e.g. xnack, sramecc, etc. so you can just use something like `precise-memory`

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