[llvm] [AArch64] Fold COPY(y:gpr, DUP(x:fpr, i)) -> UMOV(y:gpr, x:fpr, i) (PR #89017)

[Dhruv Chawla via llvm-commits]

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@@ -107,6 +108,8 @@ bool AArch64PostSelectOptimize::doPeepholeOpts(MachineBasicBlock &MBB) {
   for (auto &MI : make_early_inc_range(make_range(MBB.begin(), MBB.end()))) {
     Changed |= foldSimpleCrossClassCopies(MI);
   }
+  for (auto &MI : make_early_inc_range(make_range(MBB.begin(), MBB.end())))
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dc03-work wrote:

Unfortunately not. The problem is, if `foldSimpleCrossClassCopies` triggers, then `MI` gets invalidated because it gets deleted and calling `foldCopyDup` then causes a crash.

https://github.com/llvm/llvm-project/pull/89017