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

[Matt Arsenault 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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arsenm wrote:

Shouldn't require target checks, ideally would derive this from the used resources in the sched model 

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