[DAG] SDPatternMatch - add m_SelectCCLike(L,R,T,F,CC) matcher

[RKSimon]

Depending on target / legalisation / previous combines we might have a select(setcc(l,r,cc),t,f) or selectcc(l,r,t,f,cc) node - ideally we need to match both with a single m_SelectCCLike matcher:

https://github.com/llvm/llvm-project/blob/6daf2b956d0b805cb5b617170d137fecc33b062c/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp#L4446-L4458

[llvmbot]

Hi!

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[llvmbot]

@llvm/issue-subscribers-good-first-issue

Author: Simon Pilgrim (RKSimon)

Depending on target / legalisation / previous combines we might have a `select(setcc(l,r,cc),t,f)` or `selectcc(l,r,t,f,cc)` node - ideally we need to match both with a single m_SelectCCLike matcher:

https://github.com/llvm/llvm-project/blob/6daf2b956d0b805cb5b617170d137fecc33b062c/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp#L4446-L4458

[houngkoungting]

Hi @RKSimon , I’d like to take on this issue .

[RKSimon]

@houngkoungting any luck with this? You should be able to create it with a m_AnyOf() sequence

[houngkoungting]

Hi @RKSimon , Last week was pretty rough. I had too much on my plate. But things are settled now, and I’m working on this issue."

Sorry, I will fix it very soon.QQ
HKT

[houngkoungting]

Just a quick update:
Hi @RKSimon ,
I believe the implementation is ready, and I’ve modified two test cases to reflect the changes.
I’ll upload the patch after a final round of code formatting and cleanup.
Thanks for your patience and support!