C++ DagInit::getArgName方法代码示例

std::pair<unsigned,unsigned> 
CodeGenInstruction::ParseOperandName(const std::string &Op,
                                     bool AllowWholeOp) {
  if (Op.empty() || Op[0] != '$')
    throw TheDef->getName() + ": Illegal operand name: '" + Op + "'";
  
  std::string OpName = Op.substr(1);
  std::string SubOpName;
  
  // Check to see if this is $foo.bar.
  std::string::size_type DotIdx = OpName.find_first_of(".");
  if (DotIdx != std::string::npos) {
    SubOpName = OpName.substr(DotIdx+1);
    if (SubOpName.empty())
      throw TheDef->getName() + ": illegal empty suboperand name in '" +Op +"'";
    OpName = OpName.substr(0, DotIdx);
  }
  
  unsigned OpIdx = getOperandNamed(OpName);

  if (SubOpName.empty()) {  // If no suboperand name was specified:
    // If one was needed, throw.
    if (OperandList[OpIdx].MINumOperands > 1 && !AllowWholeOp &&
        SubOpName.empty())
      throw TheDef->getName() + ": Illegal to refer to"
            " whole operand part of complex operand '" + Op + "'";
  
    // Otherwise, return the operand.
    return std::make_pair(OpIdx, 0U);
  }
  
  // Find the suboperand number involved.
  DagInit *MIOpInfo = OperandList[OpIdx].MIOperandInfo;
  if (MIOpInfo == 0)
    throw TheDef->getName() + ": unknown suboperand name in '" + Op + "'";
  
  // Find the operand with the right name.
  for (unsigned i = 0, e = MIOpInfo->getNumArgs(); i != e; ++i)
    if (MIOpInfo->getArgName(i) == SubOpName)
      return std::make_pair(OpIdx, i);

  // Otherwise, didn't find it!
  throw TheDef->getName() + ": unknown suboperand name in '" + Op + "'";
}

static bool populateInstruction(const CodeGenInstruction &CGI,
                                unsigned Opc,
                      std::map<unsigned, std::vector<OperandInfo> >& Operands){
  const Record &Def = *CGI.TheDef;
  // If all the bit positions are not specified; do not decode this instruction.
  // We are bound to fail!  For proper disassembly, the well-known encoding bits
  // of the instruction must be fully specified.
  //
  // This also removes pseudo instructions from considerations of disassembly,
  // which is a better design and less fragile than the name matchings.
  // Ignore "asm parser only" instructions.
  if (Def.getValueAsBit("isAsmParserOnly") ||
      Def.getValueAsBit("isCodeGenOnly"))
    return false;

  BitsInit &Bits = getBitsField(Def, "Inst");
  if (Bits.allInComplete()) return false;

  std::vector<OperandInfo> InsnOperands;

  // If the instruction has specified a custom decoding hook, use that instead
  // of trying to auto-generate the decoder.
  std::string InstDecoder = Def.getValueAsString("DecoderMethod");
  if (InstDecoder != "") {
    InsnOperands.push_back(OperandInfo(InstDecoder));
    Operands[Opc] = InsnOperands;
    return true;
  }

  // Generate a description of the operand of the instruction that we know
  // how to decode automatically.
  // FIXME: We'll need to have a way to manually override this as needed.

  // Gather the outputs/inputs of the instruction, so we can find their
  // positions in the encoding.  This assumes for now that they appear in the
  // MCInst in the order that they're listed.
  std::vector<std::pair<Init*, std::string> > InOutOperands;
  DagInit *Out  = Def.getValueAsDag("OutOperandList");
  DagInit *In  = Def.getValueAsDag("InOperandList");
  for (unsigned i = 0; i < Out->getNumArgs(); ++i)
    InOutOperands.push_back(std::make_pair(Out->getArg(i), Out->getArgName(i)));
  for (unsigned i = 0; i < In->getNumArgs(); ++i)
    InOutOperands.push_back(std::make_pair(In->getArg(i), In->getArgName(i)));

  // Search for tied operands, so that we can correctly instantiate
  // operands that are not explicitly represented in the encoding.
  std::map<std::string, std::string> TiedNames;
  for (unsigned i = 0; i < CGI.Operands.size(); ++i) {
    int tiedTo = CGI.Operands[i].getTiedRegister();
    if (tiedTo != -1) {
      TiedNames[InOutOperands[i].second] = InOutOperands[tiedTo].second;
      TiedNames[InOutOperands[tiedTo].second] = InOutOperands[i].second;
    }
  }

  // For each operand, see if we can figure out where it is encoded.
  for (std::vector<std::pair<Init*, std::string> >::iterator
       NI = InOutOperands.begin(), NE = InOutOperands.end(); NI != NE; ++NI) {
    std::string Decoder = "";

    // At this point, we can locate the field, but we need to know how to
    // interpret it.  As a first step, require the target to provide callbacks
    // for decoding register classes.
    // FIXME: This need to be extended to handle instructions with custom
    // decoder methods, and operands with (simple) MIOperandInfo's.
    TypedInit *TI = dynamic_cast<TypedInit*>(NI->first);
    RecordRecTy *Type = dynamic_cast<RecordRecTy*>(TI->getType());
    Record *TypeRecord = Type->getRecord();
    bool isReg = false;
    if (TypeRecord->isSubClassOf("RegisterOperand"))
      TypeRecord = TypeRecord->getValueAsDef("RegClass");
    if (TypeRecord->isSubClassOf("RegisterClass")) {
      Decoder = "Decode" + TypeRecord->getName() + "RegisterClass";
      isReg = true;
    }

    RecordVal *DecoderString = TypeRecord->getValue("DecoderMethod");
    StringInit *String = DecoderString ?
      dynamic_cast<StringInit*>(DecoderString->getValue()) : 0;
    if (!isReg && String && String->getValue() != "")
      Decoder = String->getValue();

    OperandInfo OpInfo(Decoder);
    unsigned Base = ~0U;
    unsigned Width = 0;
    unsigned Offset = 0;

    for (unsigned bi = 0; bi < Bits.getNumBits(); ++bi) {
      VarInit *Var = 0;
      VarBitInit *BI = dynamic_cast<VarBitInit*>(Bits.getBit(bi));
      if (BI)
        Var = dynamic_cast<VarInit*>(BI->getVariable());
      else
        Var = dynamic_cast<VarInit*>(Bits.getBit(bi));

      if (!Var) {
        if (Base != ~0U) {
          OpInfo.addField(Base, Width, Offset);
          Base = ~0U;
          Width = 0;
//.........这里部分代码省略.........

CodeGenInstruction::CodeGenInstruction(Record *R, const std::string &AsmStr)
  : TheDef(R), AsmString(AsmStr) {
  Name      = R->getValueAsString("Name");
  Namespace = R->getValueAsString("Namespace");

  isReturn     = R->getValueAsBit("isReturn");
  isBranch     = R->getValueAsBit("isBranch");
  isBarrier    = R->getValueAsBit("isBarrier");
  isCall       = R->getValueAsBit("isCall");
  isLoad       = R->getValueAsBit("isLoad");
  isStore      = R->getValueAsBit("isStore");
  bool isTwoAddress = R->getValueAsBit("isTwoAddress");
  isPredicated = false;   // set below.
  isConvertibleToThreeAddress = R->getValueAsBit("isConvertibleToThreeAddress");
  isCommutable = R->getValueAsBit("isCommutable");
  isTerminator = R->getValueAsBit("isTerminator");
  isReMaterializable = R->getValueAsBit("isReMaterializable");
  hasDelaySlot = R->getValueAsBit("hasDelaySlot");
  usesCustomDAGSchedInserter = R->getValueAsBit("usesCustomDAGSchedInserter");
  hasCtrlDep   = R->getValueAsBit("hasCtrlDep");
  noResults    = R->getValueAsBit("noResults");
  hasVariableNumberOfOperands = false;
  
  DagInit *DI;
  try {
    DI = R->getValueAsDag("OperandList");
  } catch (...) {
    // Error getting operand list, just ignore it (sparcv9).
    AsmString.clear();
    OperandList.clear();
    return;
  }

  unsigned MIOperandNo = 0;
  std::set<std::string> OperandNames;
  for (unsigned i = 0, e = DI->getNumArgs(); i != e; ++i) {
    DefInit *Arg = dynamic_cast<DefInit*>(DI->getArg(i));
    if (!Arg)
      throw "Illegal operand for the '" + R->getName() + "' instruction!";

    Record *Rec = Arg->getDef();
    std::string PrintMethod = "printOperand";
    unsigned NumOps = 1;
    DagInit *MIOpInfo = 0;
    if (Rec->isSubClassOf("Operand")) {
      PrintMethod = Rec->getValueAsString("PrintMethod");
      MIOpInfo = Rec->getValueAsDag("MIOperandInfo");
      
      // Verify that MIOpInfo has an 'ops' root value.
      if (!dynamic_cast<DefInit*>(MIOpInfo->getOperator()) ||
          dynamic_cast<DefInit*>(MIOpInfo->getOperator())
               ->getDef()->getName() != "ops")
        throw "Bad value for MIOperandInfo in operand '" + Rec->getName() +
              "'\n";

      // If we have MIOpInfo, then we have #operands equal to number of entries
      // in MIOperandInfo.
      if (unsigned NumArgs = MIOpInfo->getNumArgs())
        NumOps = NumArgs;

      isPredicated |= Rec->isSubClassOf("PredicateOperand");
    } else if (Rec->getName() == "variable_ops") {
      hasVariableNumberOfOperands = true;
      continue;
    } else if (!Rec->isSubClassOf("RegisterClass") && 
               Rec->getName() != "ptr_rc")
      throw "Unknown operand class '" + Rec->getName() +
            "' in instruction '" + R->getName() + "' instruction!";

    // Check that the operand has a name and that it's unique.
    if (DI->getArgName(i).empty())
      throw "In instruction '" + R->getName() + "', operand #" + utostr(i) +
        " has no name!";
    if (!OperandNames.insert(DI->getArgName(i)).second)
      throw "In instruction '" + R->getName() + "', operand #" + utostr(i) +
        " has the same name as a previous operand!";
    
    OperandList.push_back(OperandInfo(Rec, DI->getArgName(i), PrintMethod, 
                                      MIOperandNo, NumOps, MIOpInfo));
    MIOperandNo += NumOps;
  }

  // Parse Constraints.
  ParseConstraints(R->getValueAsString("Constraints"), this);
  
  // For backward compatibility: isTwoAddress means operand 1 is tied to
  // operand 0.
  if (isTwoAddress) {
    if (!OperandList[1].Constraints[0].empty())
      throw R->getName() + ": cannot use isTwoAddress property: instruction "
            "already has constraint set!";
    OperandList[1].Constraints[0] = "((0 << 16) | (1 << TOI::TIED_TO))";
  }
  
  // Any operands with unset constraints get 0 as their constraint.
  for (unsigned op = 0, e = OperandList.size(); op != e; ++op)
    for (unsigned j = 0, e = OperandList[op].MINumOperands; j != e; ++j)
      if (OperandList[op].Constraints[j].empty())
        OperandList[op].Constraints[j] = "0";
  
//.........这里部分代码省略.........

CodeGenInstAlias::CodeGenInstAlias(Record *R, unsigned Variant,
                                   CodeGenTarget &T)
    : TheDef(R) {
    Result = R->getValueAsDag("ResultInst");
    AsmString = R->getValueAsString("AsmString");
    AsmString = CodeGenInstruction::FlattenAsmStringVariants(AsmString, Variant);


    // Verify that the root of the result is an instruction.
    DefInit *DI = dyn_cast<DefInit>(Result->getOperator());
    if (!DI || !DI->getDef()->isSubClassOf("Instruction"))
        PrintFatalError(R->getLoc(),
                        "result of inst alias should be an instruction");

    ResultInst = &T.getInstruction(DI->getDef());

    // NameClass - If argument names are repeated, we need to verify they have
    // the same class.
    StringMap<Record*> NameClass;
    for (unsigned i = 0, e = Result->getNumArgs(); i != e; ++i) {
        DefInit *ADI = dyn_cast<DefInit>(Result->getArg(i));
        if (!ADI || Result->getArgName(i).empty())
            continue;
        // Verify we don't have something like: (someinst GR16:$foo, GR32:$foo)
        // $foo can exist multiple times in the result list, but it must have the
        // same type.
        Record *&Entry = NameClass[Result->getArgName(i)];
        if (Entry && Entry != ADI->getDef())
            PrintFatalError(R->getLoc(), "result value $" + Result->getArgName(i) +
                            " is both " + Entry->getName() + " and " +
                            ADI->getDef()->getName() + "!");
        Entry = ADI->getDef();
    }

    // Decode and validate the arguments of the result.
    unsigned AliasOpNo = 0;
    for (unsigned i = 0, e = ResultInst->Operands.size(); i != e; ++i) {

        // Tied registers don't have an entry in the result dag unless they're part
        // of a complex operand, in which case we include them anyways, as we
        // don't have any other way to specify the whole operand.
        if (ResultInst->Operands[i].MINumOperands == 1 &&
                ResultInst->Operands[i].getTiedRegister() != -1)
            continue;

        if (AliasOpNo >= Result->getNumArgs())
            PrintFatalError(R->getLoc(), "not enough arguments for instruction!");

        Record *InstOpRec = ResultInst->Operands[i].Rec;
        unsigned NumSubOps = ResultInst->Operands[i].MINumOperands;
        ResultOperand ResOp(static_cast<int64_t>(0));
        if (tryAliasOpMatch(Result, AliasOpNo, InstOpRec, (NumSubOps > 1),
                            R->getLoc(), T, ResOp)) {
            // If this is a simple operand, or a complex operand with a custom match
            // class, then we can match is verbatim.
            if (NumSubOps == 1 ||
                    (InstOpRec->getValue("ParserMatchClass") &&
                     InstOpRec->getValueAsDef("ParserMatchClass")
                     ->getValueAsString("Name") != "Imm")) {
                ResultOperands.push_back(ResOp);
                ResultInstOperandIndex.push_back(std::make_pair(i, -1));
                ++AliasOpNo;

                // Otherwise, we need to match each of the suboperands individually.
            } else {
                DagInit *MIOI = ResultInst->Operands[i].MIOperandInfo;
                for (unsigned SubOp = 0; SubOp != NumSubOps; ++SubOp) {
                    Record *SubRec = cast<DefInit>(MIOI->getArg(SubOp))->getDef();

                    // Take care to instantiate each of the suboperands with the correct
                    // nomenclature: $foo.bar
                    ResultOperands.push_back(
                        ResultOperand(Result->getArgName(AliasOpNo) + "." +
                                      MIOI->getArgName(SubOp), SubRec));
                    ResultInstOperandIndex.push_back(std::make_pair(i, SubOp));
                }
                ++AliasOpNo;
            }
            continue;
        }

        // If the argument did not match the instruction operand, and the operand
        // is composed of multiple suboperands, try matching the suboperands.
        if (NumSubOps > 1) {
            DagInit *MIOI = ResultInst->Operands[i].MIOperandInfo;
            for (unsigned SubOp = 0; SubOp != NumSubOps; ++SubOp) {
                if (AliasOpNo >= Result->getNumArgs())
                    PrintFatalError(R->getLoc(), "not enough arguments for instruction!");
                Record *SubRec = cast<DefInit>(MIOI->getArg(SubOp))->getDef();
                if (tryAliasOpMatch(Result, AliasOpNo, SubRec, false,
                                    R->getLoc(), T, ResOp)) {
                    ResultOperands.push_back(ResOp);
                    ResultInstOperandIndex.push_back(std::make_pair(i, SubOp));
                    ++AliasOpNo;
                } else {
                    PrintFatalError(R->getLoc(), "result argument #" + Twine(AliasOpNo) +
                                    " does not match instruction operand class " +
                                    (SubOp == 0 ? InstOpRec->getName() :SubRec->getName()));
                }
            }
//.........这里部分代码省略.........

CGIOperandList::CGIOperandList(Record *R) : TheDef(R) {
    isPredicable = false;
    hasOptionalDef = false;
    isVariadic = false;

    DagInit *OutDI = R->getValueAsDag("OutOperandList");

    if (DefInit *Init = dyn_cast<DefInit>(OutDI->getOperator())) {
        if (Init->getDef()->getName() != "outs")
            PrintFatalError(R->getName() + ": invalid def name for output list: use 'outs'");
    } else
        PrintFatalError(R->getName() + ": invalid output list: use 'outs'");

    NumDefs = OutDI->getNumArgs();

    DagInit *InDI = R->getValueAsDag("InOperandList");
    if (DefInit *Init = dyn_cast<DefInit>(InDI->getOperator())) {
        if (Init->getDef()->getName() != "ins")
            PrintFatalError(R->getName() + ": invalid def name for input list: use 'ins'");
    } else
        PrintFatalError(R->getName() + ": invalid input list: use 'ins'");

    unsigned MIOperandNo = 0;
    std::set<std::string> OperandNames;
    for (unsigned i = 0, e = InDI->getNumArgs()+OutDI->getNumArgs(); i != e; ++i) {
        Init *ArgInit;
        std::string ArgName;
        if (i < NumDefs) {
            ArgInit = OutDI->getArg(i);
            ArgName = OutDI->getArgName(i);
        } else {
            ArgInit = InDI->getArg(i-NumDefs);
            ArgName = InDI->getArgName(i-NumDefs);
        }

        DefInit *Arg = dyn_cast<DefInit>(ArgInit);
        if (!Arg)
            PrintFatalError("Illegal operand for the '" + R->getName() + "' instruction!");

        Record *Rec = Arg->getDef();
        std::string PrintMethod = "printOperand";
        std::string EncoderMethod;
        std::string OperandType = "OPERAND_UNKNOWN";
        unsigned NumOps = 1;
        DagInit *MIOpInfo = nullptr;
        if (Rec->isSubClassOf("RegisterOperand")) {
            PrintMethod = Rec->getValueAsString("PrintMethod");
        } else if (Rec->isSubClassOf("Operand")) {
            PrintMethod = Rec->getValueAsString("PrintMethod");
            OperandType = Rec->getValueAsString("OperandType");
            // If there is an explicit encoder method, use it.
            EncoderMethod = Rec->getValueAsString("EncoderMethod");
            MIOpInfo = Rec->getValueAsDag("MIOperandInfo");

            // Verify that MIOpInfo has an 'ops' root value.
            if (!isa<DefInit>(MIOpInfo->getOperator()) ||
                    cast<DefInit>(MIOpInfo->getOperator())->getDef()->getName() != "ops")
                PrintFatalError("Bad value for MIOperandInfo in operand '" + Rec->getName() +
                                "'\n");

            // If we have MIOpInfo, then we have #operands equal to number of entries
            // in MIOperandInfo.
            if (unsigned NumArgs = MIOpInfo->getNumArgs())
                NumOps = NumArgs;

            if (Rec->isSubClassOf("PredicateOp"))
                isPredicable = true;
            else if (Rec->isSubClassOf("OptionalDefOperand"))
                hasOptionalDef = true;
        } else if (Rec->getName() == "variable_ops") {
            isVariadic = true;
            continue;
        } else if (Rec->isSubClassOf("RegisterClass")) {
            OperandType = "OPERAND_REGISTER";
        } else if (!Rec->isSubClassOf("PointerLikeRegClass") &&
                   !Rec->isSubClassOf("unknown_class"))
            PrintFatalError("Unknown operand class '" + Rec->getName() +
                            "' in '" + R->getName() + "' instruction!");

        // Check that the operand has a name and that it's unique.
        if (ArgName.empty())
            PrintFatalError("In instruction '" + R->getName() + "', operand #" +
                            Twine(i) + " has no name!");
        if (!OperandNames.insert(ArgName).second)
            PrintFatalError("In instruction '" + R->getName() + "', operand #" +
                            Twine(i) + " has the same name as a previous operand!");

        OperandList.push_back(OperandInfo(Rec, ArgName, PrintMethod, EncoderMethod,
                                          OperandType, MIOperandNo, NumOps,
                                          MIOpInfo));
        MIOperandNo += NumOps;
    }


    // Make sure the constraints list for each operand is large enough to hold
    // constraint info, even if none is present.
    for (unsigned i = 0, e = OperandList.size(); i != e; ++i)
        OperandList[i].Constraints.resize(OperandList[i].MINumOperands);
}

CodeGenInstruction::CodeGenInstruction(Record *R, const std::string &AsmStr)
  : TheDef(R), AsmString(AsmStr) {
  Namespace = R->getValueAsString("Namespace");

  isReturn     = R->getValueAsBit("isReturn");
  isBranch     = R->getValueAsBit("isBranch");
  isIndirectBranch = R->getValueAsBit("isIndirectBranch");
  isBarrier    = R->getValueAsBit("isBarrier");
  isCall       = R->getValueAsBit("isCall");
  canFoldAsLoad = R->getValueAsBit("canFoldAsLoad");
  mayLoad      = R->getValueAsBit("mayLoad");
  mayStore     = R->getValueAsBit("mayStore");
  bool isTwoAddress = R->getValueAsBit("isTwoAddress");
  isPredicable = R->getValueAsBit("isPredicable");
  isConvertibleToThreeAddress = R->getValueAsBit("isConvertibleToThreeAddress");
  isCommutable = R->getValueAsBit("isCommutable");
  isTerminator = R->getValueAsBit("isTerminator");
  isReMaterializable = R->getValueAsBit("isReMaterializable");
  hasDelaySlot = R->getValueAsBit("hasDelaySlot");
  usesCustomInserter = R->getValueAsBit("usesCustomInserter");
  hasCtrlDep   = R->getValueAsBit("hasCtrlDep");
  isNotDuplicable = R->getValueAsBit("isNotDuplicable");
  hasSideEffects = R->getValueAsBit("hasSideEffects");
  neverHasSideEffects = R->getValueAsBit("neverHasSideEffects");
  isAsCheapAsAMove = R->getValueAsBit("isAsCheapAsAMove");
  hasExtraSrcRegAllocReq = R->getValueAsBit("hasExtraSrcRegAllocReq");
  hasExtraDefRegAllocReq = R->getValueAsBit("hasExtraDefRegAllocReq");
  hasOptionalDef = false;
  isVariadic = false;
  ImplicitDefs = R->getValueAsListOfDefs("Defs");
  ImplicitUses = R->getValueAsListOfDefs("Uses");

  if (neverHasSideEffects + hasSideEffects > 1)
    throw R->getName() + ": multiple conflicting side-effect flags set!";

  DagInit *OutDI = R->getValueAsDag("OutOperandList");

  if (DefInit *Init = dynamic_cast<DefInit*>(OutDI->getOperator())) {
    if (Init->getDef()->getName() != "outs")
      throw R->getName() + ": invalid def name for output list: use 'outs'";
  } else
    throw R->getName() + ": invalid output list: use 'outs'";
    
  NumDefs = OutDI->getNumArgs();
    
  DagInit *InDI = R->getValueAsDag("InOperandList");
  if (DefInit *Init = dynamic_cast<DefInit*>(InDI->getOperator())) {
    if (Init->getDef()->getName() != "ins")
      throw R->getName() + ": invalid def name for input list: use 'ins'";
  } else
    throw R->getName() + ": invalid input list: use 'ins'";
    
  unsigned MIOperandNo = 0;
  std::set<std::string> OperandNames;
  for (unsigned i = 0, e = InDI->getNumArgs()+OutDI->getNumArgs(); i != e; ++i){
    Init *ArgInit;
    std::string ArgName;
    if (i < NumDefs) {
      ArgInit = OutDI->getArg(i);
      ArgName = OutDI->getArgName(i);
    } else {
      ArgInit = InDI->getArg(i-NumDefs);
      ArgName = InDI->getArgName(i-NumDefs);
    }
    
    DefInit *Arg = dynamic_cast<DefInit*>(ArgInit);
    if (!Arg)
      throw "Illegal operand for the '" + R->getName() + "' instruction!";

    Record *Rec = Arg->getDef();
    std::string PrintMethod = "printOperand";
    unsigned NumOps = 1;
    DagInit *MIOpInfo = 0;
    if (Rec->isSubClassOf("Operand")) {
      PrintMethod = Rec->getValueAsString("PrintMethod");
      MIOpInfo = Rec->getValueAsDag("MIOperandInfo");

      // Verify that MIOpInfo has an 'ops' root value.
      if (!dynamic_cast<DefInit*>(MIOpInfo->getOperator()) ||
          dynamic_cast<DefInit*>(MIOpInfo->getOperator())
               ->getDef()->getName() != "ops")
        throw "Bad value for MIOperandInfo in operand '" + Rec->getName() +
              "'\n";

      // If we have MIOpInfo, then we have #operands equal to number of entries
      // in MIOperandInfo.
      if (unsigned NumArgs = MIOpInfo->getNumArgs())
        NumOps = NumArgs;

      if (Rec->isSubClassOf("PredicateOperand"))
        isPredicable = true;
      else if (Rec->isSubClassOf("OptionalDefOperand"))
        hasOptionalDef = true;
    } else if (Rec->getName() == "variable_ops") {
      isVariadic = true;
      continue;
    } else if (!Rec->isSubClassOf("RegisterClass") &&
               Rec->getName() != "ptr_rc" && Rec->getName() != "unknown")
      throw "Unknown operand class '" + Rec->getName() +
            "' in '" + R->getName() + "' instruction!";
//.........这里部分代码省略.........

InvTreePatternNode *InvTreePattern::ParseTreePattern(Init *TheInit, StringRef OpName) {
  if (DefInit *DI = dyn_cast<DefInit>(TheInit)) {
    Record *R = DI->getDef();

    // On direct reference to a leaf DagNode (SDNode) or a pattern fragment, create
    // a new InvTreePatternNode.
    if (R->isSubClassOf("SDNode") || R->isSubClassOf("PatFrag")) {
      return ParseTreePattern(DagInit::get(DI, "", 
          std::vector<std::pair<Init*, std::string> >()), OpName);
    }

    // Treat as an input element
    InvTreePatternNode *Res = new InvTreePatternNode(DI);
    if (R->getName() == "node" && OpName.empty()) {
      error("'node' requires an opname to match operand lists!");
    }

    Res->setName(OpName);
    return Res;
   }

  if (IntInit *II = dyn_cast<IntInit>(TheInit)) {
    if (!OpName.empty()) {
      error("Constant int args should not have a name!");
    }
    return new InvTreePatternNode(II);
  }

  if (BitsInit *BI = dyn_cast<BitsInit>(TheInit)) {
    // Convert to IntInit
    Init *II = BI->convertInitializerTo(IntRecTy::get());
    if (II == 0 || !isa<IntInit>(II)) {
      error("Bits values must be integer constants!");
    }
    return ParseTreePattern(II, OpName);
  }

  DagInit *Dag = dyn_cast<DagInit>(TheInit);
  if (!Dag) {
    TheInit->dump();
    error("The Pattern has an unexpected init type.");
  }
  DefInit *OpDef = dyn_cast<DefInit>(Dag->getOperator());
  if (!OpDef) {
    error("Thye Pattern has an unexpected operator type.");
  }
  Record *OpRec = OpDef->getDef();

  if (OpRec->isSubClassOf("ValueType")) {
    // ValueType is the type of a leaf node.
    if (Dag->getNumArgs() != 1) {
      error("Expected 1 argument for a ValueType operator.");
    }
    InvTreePatternNode *New = ParseTreePattern(Dag->getArg(0), Dag->getArgName(0));

    // assert(New->getNumTypes() == 1 && "Unable to handle multiple types!");
    // New->UpdateNodeType(0, getValueType(OpRec), *this);

    if (!OpName.empty()) {
      error("ValueType should not have a name!");
    }
    return New;
  }

  // Verify that this makes sense for an operator
  if (!OpRec->isSubClassOf("PatFrag") && !OpRec->isSubClassOf("SDNode") &&
    !OpRec->isSubClassOf("Instruction") && !OpRec->isSubClassOf("SDNodeXForm") &&
    !OpRec->isSubClassOf("Intrinsic") && OpRec->getName() != "set" &&
    OpRec->getName() != "implicit" && OpRec->getName() != "outs" &&
    OpRec->getName() != "ins" && OpRec->getName() != "null_frag") {
    error("Unrecognized node '" + OpRec->getName() + "'!");
  }

  // Unlike Regular treepatterns, we assume all patterns are "input" patterns
  // in the TableGen context
  if (OpRec->isSubClassOf("Instruction") ||
    OpRec->isSubClassOf("SDNodeXForm")) {
    error("Cannot use '" + OpRec->getName() + "' in the output pattern.");
  }

  std::vector<InvTreePatternNode*> Children;

  // Parse operands
  for (unsigned i = 0, e = Dag->getNumArgs(); i != e; ++i) {
    Children.push_back(ParseTreePattern(Dag->getArg(i), Dag->getArgName(i)));
  }

  if (OpRec->isSubClassOf("Intrinsic")) {
    // Unhandled...
    DEBUG(error("Intrinsics unhandled at this time."););

//.........这里部分代码省略.........
        // Print out the pattern that matched...
        DEBUG(OS << "    std::cerr << \"  " << P->getRecord()->getName() <<'"');
        DEBUG(for (unsigned i = 0, e = Operands.size(); i != e; ++i)
                if (Operands[i].first->isLeaf()) {
                  Record *RV = Operands[i].first->getValueRecord();
                  assert(RV->isSubClassOf("RegisterClass") &&
                         "Only handles registers here so far!");
                  OS << " << \" %reg\" << " << Operands[i].second
                     << "->Val";
                } else {
                  OS << " << ' ' << " << Operands[i].second
                     << "->Val";
                });
        DEBUG(OS << " << \"\\n\";\n");
        
        // Generate the reduction code appropriate to the particular type of
        // pattern that this is...
        switch (P->getPatternType()) {
        case Pattern::Instruction:
          // Instruction patterns just emit a single MachineInstr, using BuildMI
          OS << "    BuildMI(MBB, " << Target.getName() << "::"
             << P->getRecord()->getName() << ", " << Operands.size();
          if (P->getResult()) OS << ", NewReg";
          OS << ")";

          for (unsigned i = 0, e = Operands.size(); i != e; ++i) {
            TreePatternNode *Op = Operands[i].first;
            if (Op->isLeaf()) {
              Record *RV = Op->getValueRecord();
              assert(RV->isSubClassOf("RegisterClass") &&
                     "Only handles registers here so far!");
              OS << ".addReg(" << Operands[i].second << "->Val)";
            } else if (Op->getOperator()->getName() == "imm") {
              OS << ".addZImm(" << Operands[i].second << "->Val)";
            } else if (Op->getOperator()->getName() == "basicblock") {
              OS << ".addMBB(" << Operands[i].second << "->Val)";
            } else {
              assert(0 && "Unknown value type!");
            }
          }
          OS << ";\n";
          break;
        case Pattern::Expander: {
          // Expander patterns emit one machine instr for each instruction in
          // the list of instructions expanded to.
          ListInit *Insts = P->getRecord()->getValueAsListInit("Result");
          for (unsigned IN = 0, e = Insts->getSize(); IN != e; ++IN) {
            DagInit *DIInst = dynamic_cast<DagInit*>(Insts->getElement(IN));
            if (!DIInst) P->error("Result list must contain instructions!");
            Record *InstRec  = DIInst->getNodeType();
            Pattern *InstPat = getPattern(InstRec);
            if (!InstPat || InstPat->getPatternType() != Pattern::Instruction)
              P->error("Instruction list must contain Instruction patterns!");
            
            bool hasResult = InstPat->getResult() != 0;
            if (InstPat->getNumArgs() != DIInst->getNumArgs()-hasResult) {
              P->error("Incorrect number of arguments specified for inst '" +
                       InstPat->getRecord()->getName() + "' in result list!");
            }

            // Start emission of the instruction...
            OS << "    BuildMI(MBB, " << Target.getName() << "::"
               << InstRec->getName() << ", "
               << DIInst->getNumArgs()-hasResult;
            // Emit register result if necessary..
            if (hasResult) {
              std::string ArgNameVal =
                getArgName(P, DIInst->getArgName(0), Operands);
              PrintExpanderOperand(DIInst->getArg(0), ArgNameVal,
                                   InstPat->getResultNode(), P, false,
                                   OS << ", ");
            }
            OS << ")";

            for (unsigned i = hasResult, e = DIInst->getNumArgs(); i != e; ++i){
              std::string ArgNameVal =
                getArgName(P, DIInst->getArgName(i), Operands);

              PrintExpanderOperand(DIInst->getArg(i), ArgNameVal,
                                   InstPat->getArg(i-hasResult), P, true, OS);
            }

            OS << ";\n";
          }
          break;
        }
        default:
          assert(0 && "Reduction of this type of pattern not implemented!");
        }

        OS << "    Val = new ReducedValue_" << SlotName << "(" << Result<<");\n"
           << "    break;\n"
           << "  }\n";
      }
    
    
    OS << "  default: assert(0 && \"Unknown " << SlotName << " pattern!\");\n"
       << "  }\n\n  N->addValue(Val);  // Do not ever recalculate this\n"
       << "  return Val;\n}\n\n";
  }