[all-commits] [llvm/llvm-project] 79c7fa: [InstCombine] check alloc size in bitcast of geps ...

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  Branch: refs/heads/master
  Home:   https://github.com/llvm/llvm-project
  Commit: 79c7fa31f3aafba77862325cdc70a3ece7f71950
      https://github.com/llvm/llvm-project/commit/79c7fa31f3aafba77862325cdc70a3ece7f71950
  Author: Sanjay Patel <spatel at rotateright.com>
  Date:   2019-12-21 (Sat, 21 Dec 2019)

  Changed paths:
    M llvm/lib/Transforms/InstCombine/InstructionCombining.cpp
    M llvm/test/Transforms/InstCombine/gep-vector.ll

  Log Message:
  -----------
  [InstCombine] check alloc size in bitcast of geps fold (PR44321)

We missed a constraint in D44833
when folding a bitcast into a GEP with vector/array types.
If the alloc sizes specified by the datalayout don't match,
this could miscompile as shown in:
https://bugs.llvm.org/show_bug.cgi?id=44321

Differential Revision: https://reviews.llvm.org/D71771