[all-commits] [llvm/llvm-project] 7cb19f: [SLP]Initialize the lane with the given value inst...

[Andrew V. Tischenko via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 7cb19fe49331f0c5a05ee67779059fb2437ab1cc
      https://github.com/llvm/llvm-project/commit/7cb19fe49331f0c5a05ee67779059fb2437ab1cc
  Author: Alexey Bataev <a.bataev at outlook.com>
  Date:   2022-01-06 (Thu, 06 Jan 2022)

  Changed paths:
    M llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp
    M llvm/test/Transforms/SLPVectorizer/AArch64/transpose-inseltpoison.ll
    M llvm/test/Transforms/SLPVectorizer/AArch64/transpose.ll
    M llvm/test/Transforms/SLPVectorizer/X86/insert-shuffle.ll
    M llvm/test/Transforms/SLPVectorizer/X86/matched-shuffled-entries.ll
    M llvm/test/Transforms/SLPVectorizer/X86/operandorder.ll

  Log Message:
  -----------
  [SLP]Initialize the lane with the given value instead of default 0.

There is a bug in the reordering analysis stage. If the element with the
given hash is not added to the map but has the same number of APOs and
instructions with same parent, but different instruction opcode, it will
be initalized with default values and then the counter is increased by
1. But the lane is not updated and default to 0 instead of the actual
   `Lane` value. It leads to the fact that the analysis is useless in
   many cases and default to lane 0 instead of actual lane with the
   minimum amount of APO operands.

Differential Revision: https://reviews.llvm.org/D116690