[all-commits] [llvm/llvm-project] dbb3a6: [Attributor][FIX] Do not replace a value with a no...

[Johannes Doerfert via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: dbb3a65f5b30ff78e0a7165b377180a00e580f8c
      https://github.com/llvm/llvm-project/commit/dbb3a65f5b30ff78e0a7165b377180a00e580f8c
  Author: Johannes Doerfert <johannes at jdoerfert.de>
  Date:   2021-07-10 (Sat, 10 Jul 2021)

  Changed paths:
    M llvm/include/llvm/Transforms/IPO/Attributor.h
    M llvm/lib/Transforms/IPO/Attributor.cpp
    M llvm/lib/Transforms/IPO/AttributorAttributes.cpp
    M llvm/test/Transforms/Attributor/IPConstantProp/PR16052.ll
    M llvm/test/Transforms/Attributor/IPConstantProp/PR26044.ll
    M llvm/test/Transforms/Attributor/IPConstantProp/return-argument.ll
    M llvm/test/Transforms/Attributor/heap_to_stack.ll
    M llvm/test/Transforms/Attributor/heap_to_stack_gpu.ll
    M llvm/test/Transforms/Attributor/memory_locations.ll
    M llvm/test/Transforms/Attributor/noalias.ll
    M llvm/test/Transforms/Attributor/nonnull.ll
    M llvm/test/Transforms/Attributor/value-simplify.ll

  Log Message:
  -----------
  [Attributor][FIX] Do not replace a value with a non-dominating instruction

We have to be careful when we replace values to not use a non-dominating
instruction. It makes sense that simplification offers those as
"simplified values" but we can't manifest them in the IR without PHI
nodes. In the future we should consider potentially adding those PHI
nodes.