[PATCH] D122390: [InstCombine] merge shuffled vector negate and multiply

[Sanjay Patel via Phabricator via llvm-commits]

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Add the "(0 - X) --> X * -1" reverse identity to the list of alternate form binops.

We need a little hack to make the existing logic work because it does not expect to move constants from op0 to op1, but the code comment hopefully makes that clear. I don't think there are any other identities like that.

Fixes #54364 ( https://github.com/llvm/llvm-project/issues/54364 ).


https://reviews.llvm.org/D122390

Files:
  llvm/lib/Transforms/InstCombine/InstCombineVectorOps.cpp
  llvm/test/Transforms/InstCombine/shuffle_select.ll

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