[all-commits] [llvm/llvm-project] 6053d1: [SLP] Retune look-ahead scores for constants

[Alexey Bataev via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 6053d19eb3bc2391fcab76eb20a8ea0462568224
      https://github.com/llvm/llvm-project/commit/6053d19eb3bc2391fcab76eb20a8ea0462568224
  Author: Alexey Bataev <a.bataev at outlook.com>
  Date:   2026-07-07 (Tue, 07 Jul 2026)

  Changed paths:
    M llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp
    M llvm/test/Transforms/PhaseOrdering/X86/avg.ll
    M llvm/test/Transforms/SLPVectorizer/AArch64/long-non-power-of-2.ll
    M llvm/test/Transforms/SLPVectorizer/RISCV/partial-vec-invalid-cost.ll
    M llvm/test/Transforms/SLPVectorizer/X86/bad-reduction.ll
    M llvm/test/Transforms/SLPVectorizer/X86/buildvector-postpone-for-dependency.ll
    M llvm/test/Transforms/SLPVectorizer/X86/buildvector-reused-with-bv-subvector.ll
    M llvm/test/Transforms/SLPVectorizer/X86/commutable-node-with-non-sched-parent.ll
    M llvm/test/Transforms/SLPVectorizer/X86/debug-info-salvage.ll
    M llvm/test/Transforms/SLPVectorizer/X86/non-power-of-2-subvectors-insert.ll
    M llvm/test/Transforms/SLPVectorizer/X86/non-schedulable-parent-multi-copyables.ll
    M llvm/test/Transforms/SLPVectorizer/X86/recalc-copyable-operand-deps-shared-inst.ll
    M llvm/test/Transforms/SLPVectorizer/X86/reduced-ordered-values-update.ll

  Log Message:
  -----------
  [SLP] Retune look-ahead scores for constants

Rescale LookAheadHeuristics scores and add ScoreSameConstants /
ScoreConstantScaleFactor so identical constants no longer score the
same as same-opcode instruction matches, fixing suboptimal operand
reordering around repeated constants (shift amounts, splat values).
Also retry a SplitVectorize alt-shuffle build for copyable-element
bundles when scheduling fails, instead of always falling back to a
gather, to fix regressions.

Reviewers: hiraditya, bababuck, RKSimon

Pull Request: https://github.com/llvm/llvm-project/pull/207548



To unsubscribe from these emails, change your notification settings at https://github.com/llvm/llvm-project/settings/notifications