[PATCH] D118037: [DAGCombine] Consider SETULT as carry flag

[Paweł Bylica via Phabricator via llvm-commits]

chfast created this revision.
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The SETcc/SETULT sets carry flag in the same way as usub, so it can
be considered as a carry flag and pulled into addcarry, subcarry nodes.

This is a draft of a change similar to https://reviews.llvm.org/D78984
but done in DAGCombiner.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D118037

Files:
  llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
  llvm/test/CodeGen/X86/addcarry.ll
  llvm/test/CodeGen/X86/cmp-carry.ll

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