[all-commits] [llvm/llvm-project] 173032: Revert "[VPlan] Mark Select VPInstructions as not ...

[Florian Hahn via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 173032902c960d4d0d67b521d8c149553d8e8ba3
      https://github.com/llvm/llvm-project/commit/173032902c960d4d0d67b521d8c149553d8e8ba3
  Author: Florian Hahn <flo at fhahn.com>
  Date:   2023-12-13 (Wed, 13 Dec 2023)

  Changed paths:
    M llvm/lib/Transforms/Vectorize/VPlanRecipes.cpp
    M llvm/test/Transforms/LoopVectorize/reduction-small-size.ll
    M llvm/test/Transforms/LoopVectorize/store-reduction-results-in-tail-folded-loop.ll

  Log Message:
  -----------
  Revert "[VPlan] Mark Select VPInstructions as not having sideeffects."

This reverts commit 19918ac34dc5d304ec6ad413ceae1d4394abe28f.

Fixes #75298. There is still a case where we miss the correct users
outside the main vector loop for reductions, and that is tail-folded
loops with reductions where the final value is stored after the loop.

This should be handled explicitly in #70253