[PATCH] D11393: [X86] Allow X86::COND_NE_OR_P and X86::COND_NP_OR_E to be reversed.

Xinliang David Li via llvm-commits llvm-commits at lists.llvm.org
Mon Jan 11 17:35:29 PST 2016


On Mon, Jan 11, 2016 at 4:59 PM, Cong Hou <congh at google.com> wrote:
> congh added a comment.
>
> In http://reviews.llvm.org/D11393#323944, @davidxl wrote:
>
>> Restart discussion on this thread:
>>
>> For the motivating example where two conditional branches have different targets,
>>
>> jne   .BB1
>>  jnp  .BB2
>>  .BB1:
>>  ...
>>  .BB2:
>>  ...
>>
>> Is it possible to teach AnalyzeBranch to recognize the pattern -- with opcode COND_NE_OR_P ?
>
>
> Yes, I think this is done in this patch. Or do I misunderstand what you mean?

The patch removes the branch condition reversing optimization in
AnalyzeBranch -- is that needed? For the motivating example, no new
opcode seems to be needed either ..

David

>
>
> http://reviews.llvm.org/D11393
>
>
>


More information about the llvm-commits mailing list