diff options
Diffstat (limited to 'lib/CodeGen/MachineCopyPropagation.cpp')
| -rw-r--r-- | lib/CodeGen/MachineCopyPropagation.cpp | 12 |
1 files changed, 2 insertions, 10 deletions
diff --git a/lib/CodeGen/MachineCopyPropagation.cpp b/lib/CodeGen/MachineCopyPropagation.cpp index 5de6dec29fb9d..7312dc5e94bdd 100644 --- a/lib/CodeGen/MachineCopyPropagation.cpp +++ b/lib/CodeGen/MachineCopyPropagation.cpp @@ -291,17 +291,9 @@ void MachineCopyPropagation::CopyPropagateBlock(MachineBasicBlock &MBB) { if (MO.isDef()) { Defs.push_back(Reg); - } else { + continue; + } else if (MO.readsReg()) ReadRegister(Reg); - } - // Treat undef use like defs for copy propagation but not for - // dead copy. We would need to do a liveness check to be sure the copy - // is dead for undef uses. - // The backends are allowed to do whatever they want with undef value - // and we cannot be sure this register will not be rewritten to break - // some false dependencies for the hardware for instance. - if (MO.isUndef()) - Defs.push_back(Reg); } // The instruction has a register mask operand which means that it clobbers |