[all-commits] [llvm/llvm-project] 6b8baf: [BPF] turn on -mattr=+alu32 for cpu version v3 and...

[yonghong-song via All-commits]

  Branch: refs/heads/master
  Home:   https://github.com/llvm/llvm-project
  Commit: 6b8baf3062cdc7bd88867e239f26b6966ee3142c
      https://github.com/llvm/llvm-project/commit/6b8baf3062cdc7bd88867e239f26b6966ee3142c
  Author: Yonghong Song <yhs at fb.com>
  Date:   2019-11-07 (Thu, 07 Nov 2019)

  Changed paths:
    M llvm/lib/Target/BPF/BPFSubtarget.cpp
    M llvm/test/CodeGen/BPF/32-bit-subreg-alu.ll

  Log Message:
  -----------
  [BPF] turn on -mattr=+alu32 for cpu version v3 and later

-mattr=+alu32 has shown good performance vs. without this attribute.
Based on discussion at
  https://lore.kernel.org/bpf/1ec37838-966f-ec0b-5223-ca9b6eb0860d@fb.com/T/#t
cpu version v3 should support -mattr=+alu32.
This patch enabled alu32 if cpu version is v3, either specified by user
or probed by the llvm.

Differential Revision: https://reviews.llvm.org/D69957