[PATCH] D93238: [VectorCombine] make load transform poison-safe

[Sanjay Patel via Phabricator via llvm-commits]

spatel created this revision.
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As noted in D93229 <https://reviews.llvm.org/D93229>, the transform from scalar load to vector load potentially leaks poison from the extra vector elements that are being loaded.

We could use `freeze` here (and x86 codegen at least appears to be the same either way), but we already have a shuffle in this logic to optionally change the vector size, so let's allow that instruction to serve both purposes.


https://reviews.llvm.org/D93238

Files:
  llvm/lib/Transforms/Vectorize/VectorCombine.cpp
  llvm/test/Transforms/VectorCombine/X86/load.ll

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