[all-commits] [llvm/llvm-project] 7ad786: [LSR] Generalize one aspect of terminator folding ...

[Philip Reames via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 7ad786a29e7bcd75bf3e7af2d96a0bf419faff64
      https://github.com/llvm/llvm-project/commit/7ad786a29e7bcd75bf3e7af2d96a0bf419faff64
  Author: Philip Reames <preames at rivosinc.com>
  Date:   2023-01-20 (Fri, 20 Jan 2023)

  Changed paths:
    M llvm/lib/Transforms/Scalar/LoopStrengthReduce.cpp
    M llvm/test/Transforms/LoopStrengthReduce/lsr-term-fold-negative-testcase.ll
    M llvm/test/Transforms/LoopStrengthReduce/lsr-term-fold.ll

  Log Message:
  -----------
  [LSR] Generalize one aspect of terminator folding (recently introduced in D132443)

There's no need to require the start value to come directly from the loop predecessor.  This was sometimes covering up a latent miscompile in this off-by-default option, but the miscompile needs fixed anyways and the issue has been raised on the original review.

Differential Revision: https://reviews.llvm.org/D142240