[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]

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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 .