[all-commits] [llvm/llvm-project] 1cbaf8: [CGP] Reset the debug location when promoting zext...

[Davide Italiano via All-commits]

  Branch: refs/heads/master
  Home:   https://github.com/llvm/llvm-project
  Commit: 1cbaf847ab84f37d9044d867b5ed8ae646c6ebc9
      https://github.com/llvm/llvm-project/commit/1cbaf847ab84f37d9044d867b5ed8ae646c6ebc9
  Author: Davide Italiano <ditaliano at apple.com>
  Date:   2020-06-17 (Wed, 17 Jun 2020)

  Changed paths:
    M llvm/lib/CodeGen/CodeGenPrepare.cpp
    M llvm/test/DebugInfo/X86/zextload.ll
    A llvm/test/Transforms/CodeGenPrepare/X86/promoted-zext-debugloc.ll

  Log Message:
  -----------
  [CGP] Reset the debug location when promoting zext(s).

When the zext gets promoted, it used to retain the original location,
which pessimizes the debugging experience causing an unexpected
jump in stepping at -Og.

Fixes https://bugs.llvm.org/show_bug.cgi?id=46120 (which also
contains a full C repro).

Differential Revision:  https://reviews.llvm.org/D81437