[all-commits] [llvm/llvm-project] 878cb3: [InstCombine] Add replaceOperand() helper

[Nikita Popov via All-commits]

  Branch: refs/heads/master
  Home:   https://github.com/llvm/llvm-project
  Commit: 878cb38a5c4272005f65554da0ec090c7c1c1f6a
      https://github.com/llvm/llvm-project/commit/878cb38a5c4272005f65554da0ec090c7c1c1f6a
  Author: Nikita Popov <nikita.ppv at gmail.com>
  Date:   2020-02-03 (Mon, 03 Feb 2020)

  Changed paths:
    M llvm/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp
    M llvm/lib/Transforms/InstCombine/InstCombineCalls.cpp
    M llvm/lib/Transforms/InstCombine/InstCombineCasts.cpp
    M llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp
    M llvm/lib/Transforms/InstCombine/InstCombineInternal.h
    M llvm/lib/Transforms/InstCombine/InstCombineLoadStoreAlloca.cpp
    M llvm/lib/Transforms/InstCombine/InstCombineMulDivRem.cpp
    M llvm/lib/Transforms/InstCombine/InstCombineVectorOps.cpp
    M llvm/lib/Transforms/InstCombine/InstructionCombining.cpp

  Log Message:
  -----------
  [InstCombine] Add replaceOperand() helper

Adds a replaceOperand() helper, which is like Instruction.setOperand()
but adds the old operand to the worklist. This reduces the amount of
missing or incorrect worklist management.

This only applies the helper to a relatively small subset of
setOperand() calls in InstCombine, namely those of the pattern
`I.setOperand(); return &I;`, where it is most obviously applicable.

Differential Revision: https://reviews.llvm.org/D73803