[PATCH] D92102: [DAG] Legalize abs(x) -> umin(x,sub(0,x)) iff umin/sub are legal

[Simon Pilgrim via Phabricator via llvm-commits]

RKSimon created this revision.
RKSimon added reviewers: spatel, lebedev.ri.
Herald added subscribers: pengfei, hiraditya.
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RKSimon requested review of this revision.

If umin() is legal, this is likely to result in smaller codegen expansion for abs(x) than the xor(add,ashr) method.

Followup to D92095 <https://reviews.llvm.org/D92095>

Alive2: https://alive2.llvm.org/ce/z/8nuX6s


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D92102

Files:
  llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp
  llvm/test/CodeGen/X86/abs.ll
  llvm/test/CodeGen/X86/combine-abs.ll
  llvm/test/CodeGen/X86/viabs.ll

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