[all-commits] [llvm/llvm-project] b21175: [DebugInfo][RemoveDIs] Avoid crash and output-diff...

[Jeremy Morse via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: b21175258b9a9a930acddef8ebc911e39095a436
      https://github.com/llvm/llvm-project/commit/b21175258b9a9a930acddef8ebc911e39095a436
  Author: Jeremy Morse <jeremy.morse at sony.com>
  Date:   2023-12-05 (Tue, 05 Dec 2023)

  Changed paths:
    M llvm/lib/Transforms/Utils/LoopRotationUtils.cpp
    A llvm/test/Transforms/LoopRotate/delete-dbg-values.ll

  Log Message:
  -----------
  [DebugInfo][RemoveDIs] Avoid crash and output-difference in loop-rotate (#74093)

Avoid editing a range of DPValues and then remapping them. This occurs
when we try to de-duplicate dbg.values, but then re-use the same
iterator range. We can instead remap them, and then erase any
duplicates.

At the same time refactor the computation of seen-intrinsic hashes, and
account for a peculiarity of loop-rotates existing behaviour: it will
only deduplicate dbg.values that are immediately before the preheaders
branch instruction, not just any dbg.value in the preheader.