[all-commits] [llvm/llvm-project] ca9d07: [AArch64] Decompose FADD reductions with known zer...

[Guy David via All-commits]

  Branch: refs/heads/users/guy-david/aarch64-decompose-faddv
  Home:   https://github.com/llvm/llvm-project
  Commit: ca9d07e7aee7499d540107bdf59cbb5f58815482
      https://github.com/llvm/llvm-project/commit/ca9d07e7aee7499d540107bdf59cbb5f58815482
  Author: Guy David <guyda96 at gmail.com>
  Date:   2026-02-15 (Sun, 15 Feb 2026)

  Changed paths:
    M llvm/lib/Target/AArch64/AArch64ISelLowering.cpp
    A llvm/test/CodeGen/AArch64/faddv.ll

  Log Message:
  -----------
  [AArch64] Decompose FADD reductions with known zero elements

FADDV is matched into FADDPv4f32 + FADDPv2f32p but this can be relaxed
when one element (usually the 4th) or more are known to be zero.

Before:
movi d1, #0000000000000000
mov v0.s[3], v1.s[0]
faddp v0.4s, v0.4s, v0.4s
faddp s0, v0.2s

After:
mov s1, v0.s[2]
faddp s0, v0.2s
fadd s0, s0, s1



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