for (int i = MI->getNumOperands() - 1; i >= 0; --i) {
MachineOperand &op = MI->getOperand(i);
- if (op.isRegister() && MRegisterInfo::isVirtualRegister(op.getReg())) {
+ if (op.isRegister() && op.getReg() &&
+ MRegisterInfo::isVirtualRegister(op.getReg())) {
unsigned virtualReg = (unsigned) op.getReg();
DEBUG(std::cerr << "op: " << op << "\n");
DEBUG(std::cerr << "\t inst[" << i << "]: ";