[all-commits] [llvm/llvm-project] 307ace: [LoopVectorize] Ensure the VPReductionRecipe is pl...

[david-arm via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 307ace7f20d5909d97ef6e81dbfa01e282a845e1
      https://github.com/llvm/llvm-project/commit/307ace7f20d5909d97ef6e81dbfa01e282a845e1
  Author: David Sherwood <david.sherwood at arm.com>
  Date:   2022-07-13 (Wed, 13 Jul 2022)

  Changed paths:
    M llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
    M llvm/test/Transforms/LoopVectorize/AArch64/scalable-strict-fadd.ll
    M llvm/test/Transforms/LoopVectorize/AArch64/strict-fadd.ll

  Log Message:
  -----------
  [LoopVectorize] Ensure the VPReductionRecipe is placed after all it's inputs

When vectorising ordered reductions we call a function
LoopVectorizationPlanner::adjustRecipesForReductions to replace the
existing VPWidenRecipe for the fadd instruction with a new
VPReductionRecipe. We attempt to insert the new recipe in the same
place, but this is wrong because createBlockInMask may have
generated new recipes that VPReductionRecipe now depends upon. I
have changed the insertion code to append the recipe to the
VPBasicBlock instead.

Added a new RUN with tail-folding enabled to the existing test:

  Transforms/LoopVectorize/AArch64/scalable-strict-fadd.ll

Differential Revision: https://reviews.llvm.org/D129550