[llvm] [AMDGPU][SIInsertWaitcnts] Do not add s_waitcnt when the counters are known to be 0 already (PR #72830)

[Jay Foad via llvm-commits]

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@@ -8703,6 +8703,9 @@ bool SIInstrInfo::isAsmOnlyOpcode(int MCOp) const {
 }
 
 int SIInstrInfo::pseudoToMCOpcode(int Opcode) const {
+  if (SIInstrInfo::isSoftWaitcnt(Opcode))
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jayfoad wrote:

I really don't like adding more special cases here, but I don't have a better suggestion so I suppose it should not block this patch.

https://github.com/llvm/llvm-project/pull/72830