[llvm] [AMDGPU][GFX1250] Insert S_WAIT_XCNT for SMEM and VMEM load-stores (PR #145566)

[Jay Foad via llvm-commits]

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@@ -2096,6 +2179,11 @@ bool SIInsertWaitcnts::mayAccessScratchThroughFlat(
   });
 }
 
+bool SIInsertWaitcnts::isVmemAccess(const MachineInstr &MI) const {
+  return (TII->isFLAT(MI) && mayAccessVMEMThroughFlat(MI)) ||
+         (TII->isVMEM(MI) && !AMDGPU::getMUBUFIsBufferInv(MI.getOpcode()));
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jayfoad wrote:

`isVMEM` now includes `isFLAT`, so I think this simplifies to:
```suggestion
  return TII->isVMEM(MI) && !AMDGPU::getMUBUFIsBufferInv(MI.getOpcode());
```
which is maybe not what you want because it has lost the `mayAccessVMEMThroughFlat` check. See #137148. Cc @ro-i.

https://github.com/llvm/llvm-project/pull/145566