[all-commits] [llvm/llvm-project] 621183: [X86] Add test case showing failure to remove unne...

[Simon Pilgrim via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 621183cb45b93517169787bb254705ab3baff2a2
      https://github.com/llvm/llvm-project/commit/621183cb45b93517169787bb254705ab3baff2a2
  Author: Simon Pilgrim <llvm-dev at redking.me.uk>
  Date:   2023-11-29 (Wed, 29 Nov 2023)

  Changed paths:
    A llvm/test/CodeGen/X86/addr-mode-matcher-4.ll

  Log Message:
  -----------
  [X86] Add test case showing failure to remove unnecessary zext from address math

Thanks to @yubingex007-a11y for the original test case


  Commit: 0fac9da7342e7846fbc4464abe5c00086cbf026c
      https://github.com/llvm/llvm-project/commit/0fac9da7342e7846fbc4464abe5c00086cbf026c
  Author: Simon Pilgrim <llvm-dev at redking.me.uk>
  Date:   2023-11-29 (Wed, 29 Nov 2023)

  Changed paths:
    M llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
    M llvm/test/CodeGen/X86/addr-mode-matcher-4.ll

  Log Message:
  -----------
  [DAG] getNode() - relax (zext (trunc x)) -> x fold iff the upper bits are known zero.

Just leave the (zext (trunc (and x, c))) pattern which is still being used to create some zext_inreg patterns.


Compare: https://github.com/llvm/llvm-project/compare/511218642bc5...0fac9da7342e