[all-commits] [llvm/llvm-project] 42cf9c: [RISCV] Mark Sub/AddChainWithSubs as legal reducti...

[Luke Lau via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 42cf9c60d77689cbaad5b6a5727c3be0f7f9a605
      https://github.com/llvm/llvm-project/commit/42cf9c60d77689cbaad5b6a5727c3be0f7f9a605
  Author: Luke Lau <luke at igalia.com>
  Date:   2025-08-21 (Thu, 21 Aug 2025)

  Changed paths:
    M llvm/lib/Target/RISCV/RISCVTargetTransformInfo.h
    M llvm/test/Transforms/LoopVectorize/RISCV/reductions.ll

  Log Message:
  -----------
  [RISCV] Mark Sub/AddChainWithSubs as legal reduction types (#154753)

We used to vectorize these scalably but after #147026 they were split
out from RecurKind::Add into their own RecurKinds, and we didn't mark
them as supported in isLegalToVectorizeReduction.

This caused the loop vectorizer to drop the scalable VPlan because it
thinks the reductions will be scalarized.

This fixes it by just marking them as supported.

Fixes #154554



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