[all-commits] [llvm/llvm-project] 9cfa9b: [CodeGenPrepare] The instruction to be sunk should...

[Guo-Peilin via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 9cfa9b44a589438d3c6920881c5619c76479dbaa
      https://github.com/llvm/llvm-project/commit/9cfa9b44a589438d3c6920881c5619c76479dbaa
  Author: Tiehu Zhang <zhangtiehu at huawei.com>
  Date:   2021-08-17 (Tue, 17 Aug 2021)

  Changed paths:
    M llvm/lib/CodeGen/CodeGenPrepare.cpp
    M llvm/test/Transforms/CodeGenPrepare/AArch64/sink-free-instructions-inseltpoison.ll
    M llvm/test/Transforms/CodeGenPrepare/AArch64/sink-free-instructions.ll
    M llvm/test/Transforms/CodeGenPrepare/ARM/sink-free-instructions-inseltpoison.ll
    M llvm/test/Transforms/CodeGenPrepare/ARM/sink-free-instructions.ll

  Log Message:
  -----------
  [CodeGenPrepare] The instruction to be sunk should be inserted before its user in a block

In current implementation, the instruction to be sunk will be inserted before the target instruction without considering the def-use tree,
which may case Instruction does not dominate all uses error. We need to choose a suitable location to insert according to the use chain

Reviewed By: dmgreen

Differential Revision: https://reviews.llvm.org/D107262