[all-commits] [llvm/llvm-project] ce14d1: [SLP]Do not reorder reduction nodes.

[Andrew V. Tischenko via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: ce14d1b690d886ff6022a5cc0f2e40cc8ecb9a46
      https://github.com/llvm/llvm-project/commit/ce14d1b690d886ff6022a5cc0f2e40cc8ecb9a46
  Author: Alexey Bataev <a.bataev at outlook.com>
  Date:   2021-10-26 (Tue, 26 Oct 2021)

  Changed paths:
    M llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp
    M llvm/test/Transforms/PhaseOrdering/X86/vector-reductions.ll
    M llvm/test/Transforms/SLPVectorizer/X86/horizontal-list.ll

  Log Message:
  -----------
  [SLP]Do not reorder reduction nodes.

The final reduction nodes should not be reordered, the order does not
matter for reductions. Also, it might be profitable to vectorize smaller
reduction trees, reduction cost may compensate small tree cost.

Part of D111574

Differential Revision: https://reviews.llvm.org/D112467