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

[David Green 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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davemgreen wrote:

We should try to avoid iterating over the instructions multiple times wherever possible. We might, in the long run, want to have this loop switch on the opcode. Having it continue if foldSimpleCrossClassCopies returns true is Ok for the time being though.

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