[llvm] [NFC][AArch64] Refactor AArch64LoopIdiomTransform in preparation for more idioms (PR #78471)

[via llvm-commits]

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@@ -592,7 +660,8 @@ Value *AArch64LoopIdiomTransform::expandFindMismatch(
   Value *SVERhsLoad = Builder.CreateMaskedLoad(SVELoadType, SVERhsGep, Align(1),
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JeffHDF wrote:

Have you try to use normal load? And generate an epilogue loop after the SVE loop, I think there may be more performance impovement.

https://github.com/llvm/llvm-project/pull/78471