[all-commits] [llvm/llvm-project] c6b62e: [ConstantFold] Fold operations to poison if possible

[Juneyoung Lee via All-commits]

  Branch: refs/heads/master
  Home:   https://github.com/llvm/llvm-project
  Commit: c6b62efb9103466b6cefca1bd99a5b04b4ced044
      https://github.com/llvm/llvm-project/commit/c6b62efb9103466b6cefca1bd99a5b04b4ced044
  Author: Juneyoung Lee <aqjune at gmail.com>
  Date:   2020-11-29 (Sun, 29 Nov 2020)

  Changed paths:
    M llvm/lib/IR/ConstantFold.cpp
    M llvm/lib/IR/Constants.cpp
    M llvm/test/Transforms/InstSimplify/ConstProp/InsertElement.ll
    A llvm/test/Transforms/InstSimplify/ConstProp/poison.ll
    M llvm/unittests/IR/ConstantsTest.cpp

  Log Message:
  -----------
  [ConstantFold] Fold operations to poison if possible

This patch updates ConstantFold, so operations are folded into poison if possible.

<alive2 proofs>
casts: https://alive2.llvm.org/ce/z/WSj7rw
binary operations (arithmetic): https://alive2.llvm.org/ce/z/_7dEyJ
binary operations (bitwise): https://alive2.llvm.org/ce/z/cezjVN
vector/aggregate operations: https://alive2.llvm.org/ce/z/BQ7hWz
unary ops: https://alive2.llvm.org/ce/z/yBRs4q
other ops: https://alive2.llvm.org/ce/z/iXbcFD

Reviewed By: nikic

Differential Revision: https://reviews.llvm.org/D92203