[all-commits] [llvm/llvm-project] 233fb9: [ARM] Improve bitwise reduction costs

[David Green via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 233fb987fcf6a5dc2d12b07cb8e30fffd5471871
      https://github.com/llvm/llvm-project/commit/233fb987fcf6a5dc2d12b07cb8e30fffd5471871
  Author: David Green <david.green at arm.com>
  Date:   2023-09-04 (Mon, 04 Sep 2023)

  Changed paths:
    M llvm/lib/Target/ARM/ARMTargetTransformInfo.cpp
    M llvm/test/Analysis/CostModel/ARM/reduce-bit.ll

  Log Message:
  -----------
  [ARM] Improve bitwise reduction costs

This adds some basic and/or/xor reduction costs for NEON/MVE, handling them
like other reductions where vector operations are used to reduce to legal
sizes, followed by an optional VREV+VAND/VORR/VEOR step and scalarization from
there.