[llvm] [AMDGPU] remove move instruction if there is no user of it (PR #136735)

[Jay Foad via llvm-commits]

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@@ -797,7 +797,7 @@ MachineInstr *SIShrinkInstructions::matchSwap(MachineInstr &MovT) const {
     dropInstructionKeepingImpDefs(*MovY);
     MachineInstr *Next = &*std::next(MovT.getIterator());
 
-    if (T.isVirtual() && MRI->use_nodbg_empty(T)) {
+    if (MRI->use_nodbg_empty(T)) {
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jayfoad wrote:

I agree - as far as I can see, the use list for physical registers does not include any aliasing registers, so the committed patch is not safe and should be reverted.

https://github.com/llvm/llvm-project/pull/136735