[all-commits] [llvm/llvm-project] 2ec7bb: Recommit "[VPlan] Insert Trunc/Exts for reductions...

[Florian Hahn via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 2ec7bba77bf573e2fb134c3f6ed10a8fcdde6fe7
      https://github.com/llvm/llvm-project/commit/2ec7bba77bf573e2fb134c3f6ed10a8fcdde6fe7
  Author: Florian Hahn <flo at fhahn.com>
  Date:   2023-10-20 (Fri, 20 Oct 2023)

  Changed paths:
    M llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
    M llvm/test/Transforms/LoopVectorize/epilog-vectorization-reductions.ll
    M llvm/test/Transforms/LoopVectorize/interleave-and-scalarize-only.ll
    M llvm/test/Transforms/LoopVectorize/reduction-small-size.ll
    M llvm/test/Transforms/LoopVectorize/scalable-reduction-inloop.ll

  Log Message:
  -----------
  Recommit "[VPlan] Insert Trunc/Exts for reductions directly in VPlan."

This reverts commit e4ea0997486000b460c4875a00301b73b3c0d6a7.

The recommit fixes a reported crash by adding a missing check to make
sure the cast recipes are only introduced when vectorizing.

Test coverage added in 3cac608fbd0811b2f5c59c6e13148162ccd8543e.
Original commit message:
   Update the code to create Trunc/Ext recipes directly in
    adjustRecipesForReductions instead of fixing it up later in
    fixReductions.

    This explicitly models the required conversions and also makes sure they
    are generated at the right place (instead of after the exit condition),
    hence the changes in a few tests.