[clang] [llvm] [AMDGPU] Emit a waitcnt instruction after each memory instruction (PR #68932)

[Jay Foad via cfe-commits]

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@@ -1708,6 +1710,13 @@ bool SIInsertWaitcnts::insertWaitcntInBlock(MachineFunction &MF,
     }
 
     ++Iter;
+    if (ST->isPreciseMemoryEnabled() && Inst.mayLoadOrStore()) {
+      auto builder =
+          BuildMI(Block, Iter, DebugLoc(), TII->get(AMDGPU::S_WAITCNT))
+              .addImm(0);
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jayfoad wrote:

On GFX10+ VMEM stores should have S_WAITCNT_VSCNT 0 as well as (or instead of) this.

https://github.com/llvm/llvm-project/pull/68932