int AlphaCodeEmitter::getMachineOpValue(MachineInstr &MI, MachineOperand &MO) {

  int rv = 0; // Return value; defaults to 0 for unhandled cases
              // or things that get fixed up later by the JIT.

  if (MO.isRegister()) {
    rv = getAlphaRegNumber(MO.getReg());
  } else if (MO.isImmediate()) {
    rv = MO.getImm();
  } else if (MO.isGlobalAddress() || MO.isExternalSymbol()
             || MO.isConstantPoolIndex()) {
    DOUT << MO << " is a relocated op for " << MI << "\n";
    unsigned Reloc = 0;
    int Offset = 0;
    bool useGOT = false;
    switch (MI.getOpcode()) {
    case Alpha::BSR:
      Reloc = Alpha::reloc_bsr;
      break;
    case Alpha::LDLr:
    case Alpha::LDQr:
    case Alpha::LDBUr:
    case Alpha::LDWUr:
    case Alpha::LDSr:
    case Alpha::LDTr:
    case Alpha::LDAr:
    case Alpha::STQr:
    case Alpha::STLr:
    case Alpha::STWr:
    case Alpha::STBr:
    case Alpha::STSr:
    case Alpha::STTr:
      Reloc = Alpha::reloc_gprellow;
      break;
    case Alpha::LDAHr:
      Reloc = Alpha::reloc_gprelhigh;
      break;
    case Alpha::LDQl:
      Reloc = Alpha::reloc_literal;
      useGOT = true;
      break;
    case Alpha::LDAg:
    case Alpha::LDAHg:
      Reloc = Alpha::reloc_gpdist;
      Offset = MI.getOperand(3).getImm();
      break;
    default:
      assert(0 && "unknown relocatable instruction");
      abort();
    }
    if (MO.isGlobalAddress())
      MCE.addRelocation(MachineRelocation::getGV(MCE.getCurrentPCOffset(),
                                                 Reloc, MO.getGlobal(), Offset,
                                                 isa<Function>(MO.getGlobal()),
                                                 useGOT));
    else if (MO.isExternalSymbol())
      MCE.addRelocation(MachineRelocation::getExtSym(MCE.getCurrentPCOffset(),
                                                     Reloc, MO.getSymbolName(),
                                                     Offset, true));
    else
     MCE.addRelocation(MachineRelocation::getConstPool(MCE.getCurrentPCOffset(),
                                          Reloc, MO.getIndex(), Offset));
  } else if (MO.isMachineBasicBlock()) {
    MCE.addRelocation(MachineRelocation::getBB(MCE.getCurrentPCOffset(),
                                               Alpha::reloc_bsr, MO.getMBB()));
  }else {
    cerr << "ERROR: Unknown type of MachineOperand: " << MO << "\n";
    abort();
  }

  return rv;
}