[llvm] Co-issue packed instructions by unpacking (PR #151704)

[via llvm-commits]

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@@ -6173,6 +6172,64 @@ bool SIInstrInfo::isOperandLegal(const MachineInstr &MI, unsigned OpIdx,
   return isImmOperandLegal(MI, OpIdx, *MO);
 }
 
+bool SIInstrInfo::isNeverCoissue(MachineInstr &MI) const {
+  bool IsGFX950Only = ST.hasGFX950Insts();
+  if (!IsGFX950Only)
+    return false;
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carlobertolli wrote:

I'd like to suggest to limit the scope of this patch to MI300X and MI350 for now and do local testing, with the promise of expanding this as suggested in a forthcoming patch.

https://github.com/llvm/llvm-project/pull/151704