[PATCH] D127531: [SLP]Improve analysis of same/alternate code ops and scheduling.

Wed Jun 22 10:16:59 PDT 2022

ABataev added a comment.

In D127531#3602270 <https://reviews.llvm.org/D127531#3602270>, @vdmitrie wrote:

> In D127531#3602238 <https://reviews.llvm.org/D127531#3602238>, @ABataev wrote:
>
>> In D127531#3602215 <https://reviews.llvm.org/D127531#3602215>, @vdmitrie wrote:
>>
>>> I'm not sure about how the test case affected supposed to execute the changes.
>>> Could you please consider adding more tests to be clearer about the patch purpose?
>>
>> It is for compile time mostly, nothing else. Just allows to detect gathered elements before scheduling.
>
> Yes, but the summary also says more vector instructions generated. What specific cases are handled now but failed previously?

1-2 more instruction. The effect is caused by the better operand reordering. getSameOpcode is used to detect compatible operations, when SLP tries to find better ordering of the operands. The patch just make getSameOpcode a bit better on detecting such compatible ops.

Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D127531/new/

https://reviews.llvm.org/D127531