[llvm] [AMDGPU]: Unpack packed instructions overlapped by MFMAs post-RA scheduling (PR #157968)

[Matt Arsenault via llvm-commits]

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@@ -6359,6 +6359,66 @@ bool SIInstrInfo::isOperandLegal(const MachineInstr &MI, unsigned OpIdx,
   return isImmOperandLegal(MI, OpIdx, *MO);
 }
 
+bool SIInstrInfo::isNeverCoissue(MachineInstr &MI) const {
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arsenm wrote:

Is it possible to extract this information from the scheduler model without maintaining this list of instructions? i.e. there should be some execution resource you can check if the instruction uses 

https://github.com/llvm/llvm-project/pull/157968