[all-commits] [llvm/llvm-project] f523e8: [x86] make helper function to create sbb with zero...

[Sanjay Patel via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: f523e83b204ea3e4ab80df6bccaabf0b113ff741
      https://github.com/llvm/llvm-project/commit/f523e83b204ea3e4ab80df6bccaabf0b113ff741
  Author: Sanjay Patel <spatel at rotateright.com>
  Date:   2022-02-02 (Wed, 02 Feb 2022)

  Changed paths:
    M llvm/lib/Target/X86/X86ISelDAGToDAG.cpp

  Log Message:
  -----------
  [x86] make helper function to create sbb with zero operands; NFC

As noted in D116804, we want to effectively invert that patch
for CPUs (intel) that don't break the false dependency on
sbb %eax, %eax

So we will likely want to create that here in the
X86DAGToDAGISel::Select() case for X86::SETCC_CARRY.


  Commit: 0e9a3d3603db19e33a7af2575f449cbd564470a0
      https://github.com/llvm/llvm-project/commit/0e9a3d3603db19e33a7af2575f449cbd564470a0
  Author: Sanjay Patel <spatel at rotateright.com>
  Date:   2022-02-02 (Wed, 02 Feb 2022)

  Changed paths:
    A llvm/test/CodeGen/X86/sbb-false-dep.ll

  Log Message:
  -----------
  [x86] add test for 'sbb' false dependency stall; NFC


Compare: https://github.com/llvm/llvm-project/compare/8680d6db1e45...0e9a3d3603db