[all-commits] [llvm/llvm-project] 57f0ee: [InstSimplify] allow insertelement-with-undef fold...

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  Branch: refs/heads/master
  Home:   https://github.com/llvm/llvm-project
  Commit: 57f0eed98d02cd684c358a45f68e716179f4bfa3
      https://github.com/llvm/llvm-project/commit/57f0eed98d02cd684c358a45f68e716179f4bfa3
  Author: Sanjay Patel <spatel at rotateright.com>
  Date:   2020-05-01 (Fri, 01 May 2020)

  Changed paths:
    M llvm/lib/Analysis/InstructionSimplify.cpp
    M llvm/test/Transforms/InstSimplify/insertelement.ll

  Log Message:
  -----------
  [InstSimplify] allow insertelement-with-undef fold if poison-safe

The more general fold was not poison-safe, so it was removed:
rG5486e00
...but it is ok to have this transform if analysis can determine
the vector contains no poison. The test shows a simple example
of that: constant integer elements are not poison.