[all-commits] [llvm/llvm-project] 7c0089: [Matrix] Check if iterator is at beginning of BB i...

[Florian Hahn via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 7c0089d7351cf7ab067e987aa2e32db4b07b3adf
      https://github.com/llvm/llvm-project/commit/7c0089d7351cf7ab067e987aa2e32db4b07b3adf
  Author: Florian Hahn <flo at fhahn.com>
  Date:   2022-06-14 (Tue, 14 Jun 2022)

  Changed paths:
    M llvm/lib/Transforms/Scalar/LowerMatrixIntrinsics.cpp
    A llvm/test/Transforms/LowerMatrixIntrinsics/transpose-opts-iterator-invalidation.ll

  Log Message:
  -----------
  [Matrix] Check if iterator is at beginning of BB in optimizeTranspose.

If an instruction at the beginning of a block is erased,  this may
trigger crash due to dereferencing an invalid iterator.

Check if II is at the end before dereferencing it.

Reviewed By: thegameg

Differential Revision: https://reviews.llvm.org/D127736