[PATCH] D34300: [AMDGPU] simplify add x, *ext (setcc) => addc|subb x, 0, setcc

[Stanislav Mekhanoshin via Phabricator via llvm-commits]

rampitec added a comment.

> In https://reviews.llvm.org/D34300#784872, @arsenm wrote:
> 
>> I think the right one is    ADDCARRY, SUBCARRY:
>>
>> The use of this opcode is preferable to adde/sube if the
>>
>>   /// target supports it, as the carry is a regular value rather than a
>>   /// glue, which allows further optimisation.
> 
> 
> It seems to be so new that I do not even see a def for them in TargTargetSelectionDAG.td. Am I missing something?

They do not look like normal nodes. They would require custom select I guess.


Repository:
  rL LLVM

https://reviews.llvm.org/D34300