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

[Pierre van Houtryve via cfe-commits]

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@@ -2326,6 +2326,20 @@ bool SIInsertWaitcnts::insertWaitcntInBlock(MachineFunction &MF,
     }
 #endif
 
+    if (ST->isPreciseMemoryEnabled()) {
+      AMDGPU::Waitcnt Wait;
+      if (WCG == &WCGPreGFX12)
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Pierre-vh wrote:

Use `ST->hasExtendedWaitCounts()` instead of checking the pointer?

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