[all-commits] [llvm/llvm-project] 75188b: [PHIEliminate] Move dbg values after phi and label

[Chris Ye via All-commits]

  Branch: refs/heads/master
  Home:   https://github.com/llvm/llvm-project
  Commit: 75188b01e9af3a89639d84be912f84610d6885ba
      https://github.com/llvm/llvm-project/commit/75188b01e9af3a89639d84be912f84610d6885ba
  Author: Chris Ye <yechunliang at gmail.com>
  Date:   2020-01-16 (Thu, 16 Jan 2020)

  Changed paths:
    M llvm/lib/CodeGen/MachineVerifier.cpp
    M llvm/lib/CodeGen/PHIElimination.cpp
    M llvm/lib/CodeGen/SelectionDAG/ScheduleDAGSDNodes.cpp
    A llvm/test/CodeGen/X86/dbg-changes-codegen-phi-elimination.ll

  Log Message:
  -----------
  [PHIEliminate] Move dbg values after phi and label

If there are DBG_VALUEs between phi and label (after phi and before label),
DBG_VALUE will block PHI lowering after the LABEL. Moving all DBG_VALUEs
after Labels in the function ScheduleDAGSDNodes::EmitSchedule to avoid
impacting PHI lowering.

  before:
     PHI
     DBG_VALUE
     LABEL
  after: (move DBG_VALUE after label)
     PHI
     LABEL
     DBG_VALUE
  then: (phi lowering after label)
     LABEL
     COPY
     DBG_VALUE

Fixes the issue: https://bugs.llvm.org/show_bug.cgi?id=43859

Differential Revision: https://reviews.llvm.org/D70597