[llvm] [AMDGPU][gfx1250] Add wait_xcnt before any access that cannot be repeated (PR #168852)

[Jay Foad via llvm-commits]

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@@ -9934,6 +9934,11 @@ void SIInstrInfo::fixImplicitOperands(MachineInstr &MI) const {
   }
 }
 
+bool SIInstrInfo::isVBUFFER(const MachineInstr &MI) const {
+  return (ST.getGeneration() == GCNSubtarget::GFX12) &&
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jayfoad wrote:

I would prefer to have the isGFX12 check done in SIMemoryLegalizer, right next to the FIXME comment that explains why we need it. Then this helper function can become a generation-independent `isBUF`.

Also nit: you don't need the parens.

https://github.com/llvm/llvm-project/pull/168852