diff options
Diffstat (limited to 'llvm/lib/CodeGen/MachineCopyPropagation.cpp')
| -rw-r--r-- | llvm/lib/CodeGen/MachineCopyPropagation.cpp | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/llvm/lib/CodeGen/MachineCopyPropagation.cpp b/llvm/lib/CodeGen/MachineCopyPropagation.cpp index 1f1601b..03eac55 100644 --- a/llvm/lib/CodeGen/MachineCopyPropagation.cpp +++ b/llvm/lib/CodeGen/MachineCopyPropagation.cpp @@ -462,7 +462,8 @@ bool MachineCopyPropagation::eraseIfRedundant(MachineInstr &Copy, auto PrevCopyOperands = isCopyInstr(*PrevCopy, *TII, UseCopyInstr); // Check that the existing copy uses the correct sub registers. - if (PrevCopyOperands->Destination->isDead()) + if (PrevCopyOperands->Destination->isDead() || + PrevCopyOperands->Source->isUndef()) return false; if (!isNopCopy(*PrevCopy, Src, Def, TRI, TII, UseCopyInstr)) return false; |