[all-commits] [llvm/llvm-project] 8feca1: AMDGPU: Generalize truncate of shift of cast build...

[Matt Arsenault via All-commits]

  Branch: refs/heads/users/arsenm/amdgpu-generalize-truncate-combine
  Home:   https://github.com/llvm/llvm-project
  Commit: 8feca1b6c1af1308e443c9ca00db918b09bcb43f
      https://github.com/llvm/llvm-project/commit/8feca1b6c1af1308e443c9ca00db918b09bcb43f
  Author: Matt Arsenault <Matthew.Arsenault at amd.com>
  Date:   2025-02-04 (Tue, 04 Feb 2025)

  Changed paths:
    M llvm/lib/Target/AMDGPU/AMDGPUISelLowering.cpp
    A llvm/test/CodeGen/AMDGPU/truncate-lshr-cast-build-vector-combine.ll

  Log Message:
  -----------
  AMDGPU: Generalize truncate of shift of cast build_vector combine

Previously we only handled cases that looked like the high element
extract of a 64-bit shift. Generalize this to handle any multiple
indexing. I was hoping this would help avoid some regressions,
but it did not. It does however reduce the number of steps the DAG
takes to process these cases.

NFC-ish, I have yet to find an example where this changes the
final output.



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