[llvm] [AMDGPU] Fix VGPR to SGPR copy for inline asm with SGPR constraint (PR #176330)

[Matt Arsenault via llvm-commits]

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@@ -1019,6 +1030,8 @@ void SIFixSGPRCopies::analyzeVGPRToSGPRCopy(MachineInstr* MI) {
 // The main function that computes the VGPR to SGPR copy score
 // and determines copy further lowering way: v_readfirstlane_b32 or moveToVALU
 bool SIFixSGPRCopies::needToBeConvertedToVALU(V2SCopyInfo *Info) {
+  if (Info->HasMandatorySGPRUse)
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arsenm wrote:

I'm worried about this breaking the other uses of the register

https://github.com/llvm/llvm-project/pull/176330