[all-commits] [llvm/llvm-project] 3a7c82: [DAG] isGuaranteedNotToBeUndefOrPoison - handle IS...

[Simon Pilgrim via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 3a7c82efb8db57f0bf1cfbbd681b3905556bd049
      https://github.com/llvm/llvm-project/commit/3a7c82efb8db57f0bf1cfbbd681b3905556bd049
  Author: Simon Pilgrim <llvm-dev at redking.me.uk>
  Date:   2021-07-31 (Sat, 31 Jul 2021)

  Changed paths:
    M llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
    M llvm/test/CodeGen/X86/freeze-constant-fold.ll
    M llvm/test/CodeGen/X86/freeze-legalize.ll

  Log Message:
  -----------
  [DAG] isGuaranteedNotToBeUndefOrPoison - handle ISD::BUILD_VECTOR nodes

If all demanded elements of the BUILD_VECTOR pass a isGuaranteedNotToBeUndefOrPoison check, then we can treat this specific demanded use of the BUILD_VECTOR as guaranteed not to be undef or poison either.

Differential Revision: https://reviews.llvm.org/D107174