Beispiel #1
0
/// reverseBitsForLittleEndianEncoding - For little-endian instruction bit
/// encodings, reverse the bit order of all instructions.
void CodeGenTarget::reverseBitsForLittleEndianEncoding() {
  if (!isLittleEndianEncoding())
    return;

  std::vector<Record*> Insts = Records.getAllDerivedDefinitions("Instruction");
  for (Record *R : Insts) {
    if (R->getValueAsString("Namespace") == "TargetOpcode" ||
        R->getValueAsBit("isPseudo"))
      continue;

    BitsInit *BI = R->getValueAsBitsInit("Inst");

    unsigned numBits = BI->getNumBits();

    SmallVector<Init *, 16> NewBits(numBits);

    for (unsigned bit = 0, end = numBits / 2; bit != end; ++bit) {
      unsigned bitSwapIdx = numBits - bit - 1;
      Init *OrigBit = BI->getBit(bit);
      Init *BitSwap = BI->getBit(bitSwapIdx);
      NewBits[bit]        = BitSwap;
      NewBits[bitSwapIdx] = OrigBit;
    }
    if (numBits % 2) {
      unsigned middle = (numBits + 1) / 2;
      NewBits[middle] = BI->getBit(middle);
    }

    BitsInit *NewBI = BitsInit::get(NewBits);

    // Update the bits in reversed order so that emitInstrOpBits will get the
    // correct endianness.
    R->getValue("Inst")->setValue(NewBI);
  }
}
static bit_value_t bitFromBits(BitsInit &bits, unsigned index) {
  if (BitInit *bit = dynamic_cast<BitInit*>(bits.getBit(index)))
    return bit->getValue() ? BIT_TRUE : BIT_FALSE;

  // The bit is uninitialized.
  return BIT_UNSET;
}
Beispiel #3
0
void CodeEmitterGen::reverseBits(std::vector<Record*> &Insts) {
  for (std::vector<Record*>::iterator I = Insts.begin(), E = Insts.end();
       I != E; ++I) {
    Record *R = *I;
    if (R->getName() == "PHI" ||
        R->getName() == "INLINEASM" ||
        R->getName() == "DBG_LABEL" ||
        R->getName() == "EH_LABEL" ||
        R->getName() == "GC_LABEL" ||
        R->getName() == "KILL" ||
        R->getName() == "EXTRACT_SUBREG" ||
        R->getName() == "INSERT_SUBREG" ||
        R->getName() == "IMPLICIT_DEF" ||
        R->getName() == "SUBREG_TO_REG" ||
        R->getName() == "COPY_TO_REGCLASS" ||
        R->getName() == "DBG_VALUE") continue;

    BitsInit *BI = R->getValueAsBitsInit("Inst");

    unsigned numBits = BI->getNumBits();
    BitsInit *NewBI = new BitsInit(numBits);
    for (unsigned bit = 0, end = numBits / 2; bit != end; ++bit) {
      unsigned bitSwapIdx = numBits - bit - 1;
      Init *OrigBit = BI->getBit(bit);
      Init *BitSwap = BI->getBit(bitSwapIdx);
      NewBI->setBit(bit, BitSwap);
      NewBI->setBit(bitSwapIdx, OrigBit);
    }
    if (numBits % 2) {
      unsigned middle = (numBits + 1) / 2;
      NewBI->setBit(middle, BI->getBit(middle));
    }
    
    // Update the bits in reversed order so that emitInstrOpBits will get the
    // correct endianness.
    R->getValue("Inst")->setValue(NewBI);
  }
}
// Prints the bit value for each position.
static void dumpBits(raw_ostream &o, BitsInit &bits) {
  unsigned index;

  for (index = bits.getNumBits(); index > 0; index--) {
    switch (bitFromBits(bits, index - 1)) {
    case BIT_TRUE:
      o << "1";
      break;
    case BIT_FALSE:
      o << "0";
      break;
    case BIT_UNSET:
      o << "_";
      break;
    default:
      assert(0 && "unexpected return value from bitFromBits");
    }
  }
}
Beispiel #5
0
//
// runMCDesc - Print out MC register descriptions.
//
void
RegisterInfoEmitter::runMCDesc(raw_ostream &OS, CodeGenTarget &Target,
                               CodeGenRegBank &RegBank) {
  EmitSourceFileHeader("MC Register Information", OS);

  OS << "\n#ifdef GET_REGINFO_MC_DESC\n";
  OS << "#undef GET_REGINFO_MC_DESC\n";

  const std::vector<CodeGenRegister*> &Regs = RegBank.getRegisters();

  // The lists of sub-registers, super-registers, and overlaps all go in the
  // same array. That allows us to share suffixes.
  typedef std::vector<const CodeGenRegister*> RegVec;
  SmallVector<RegVec, 4> SubRegLists(Regs.size());
  SmallVector<RegVec, 4> OverlapLists(Regs.size());
  SequenceToOffsetTable<RegVec, CodeGenRegister::Less> RegSeqs;

  // Precompute register lists for the SequenceToOffsetTable.
  for (unsigned i = 0, e = Regs.size(); i != e; ++i) {
    const CodeGenRegister *Reg = Regs[i];

    // Compute the ordered sub-register list.
    SetVector<const CodeGenRegister*> SR;
    Reg->addSubRegsPreOrder(SR, RegBank);
    RegVec &SubRegList = SubRegLists[i];
    SubRegList.assign(SR.begin(), SR.end());
    RegSeqs.add(SubRegList);

    // Super-registers are already computed.
    const RegVec &SuperRegList = Reg->getSuperRegs();
    RegSeqs.add(SuperRegList);

    // The list of overlaps doesn't need to have any particular order, except
    // Reg itself must be the first element. Pick an ordering that has one of
    // the other lists as a suffix.
    RegVec &OverlapList = OverlapLists[i];
    const RegVec &Suffix = SubRegList.size() > SuperRegList.size() ?
                           SubRegList : SuperRegList;
    CodeGenRegister::Set Omit(Suffix.begin(), Suffix.end());

    // First element is Reg itself.
    OverlapList.push_back(Reg);
    Omit.insert(Reg);

    // Any elements not in Suffix.
    CodeGenRegister::Set OSet;
    Reg->computeOverlaps(OSet, RegBank);
    std::set_difference(OSet.begin(), OSet.end(),
                        Omit.begin(), Omit.end(),
                        std::back_inserter(OverlapList),
                        CodeGenRegister::Less());

    // Finally, Suffix itself.
    OverlapList.insert(OverlapList.end(), Suffix.begin(), Suffix.end());
    RegSeqs.add(OverlapList);
  }

  // Compute the final layout of the sequence table.
  RegSeqs.layout();

  OS << "namespace llvm {\n\n";

  const std::string &TargetName = Target.getName();

  // Emit the shared table of register lists.
  OS << "extern const uint16_t " << TargetName << "RegLists[] = {\n";
  RegSeqs.emit(OS, printRegister);
  OS << "};\n\n";

  OS << "extern const MCRegisterDesc " << TargetName
     << "RegDesc[] = { // Descriptors\n";
  OS << "  { \"NOREG\", 0, 0, 0 },\n";

  // Emit the register descriptors now.
  for (unsigned i = 0, e = Regs.size(); i != e; ++i) {
    const CodeGenRegister *Reg = Regs[i];
    OS << "  { \"" << Reg->getName() << "\", "
       << RegSeqs.get(OverlapLists[i]) << ", "
       << RegSeqs.get(SubRegLists[i]) << ", "
       << RegSeqs.get(Reg->getSuperRegs()) << " },\n";
  }
  OS << "};\n\n";      // End of register descriptors...

  ArrayRef<CodeGenRegisterClass*> RegisterClasses = RegBank.getRegClasses();

  // Loop over all of the register classes... emitting each one.
  OS << "namespace {     // Register classes...\n";

  // Emit the register enum value arrays for each RegisterClass
  for (unsigned rc = 0, e = RegisterClasses.size(); rc != e; ++rc) {
    const CodeGenRegisterClass &RC = *RegisterClasses[rc];
    ArrayRef<Record*> Order = RC.getOrder();

    // Give the register class a legal C name if it's anonymous.
    std::string Name = RC.getName();

    // Emit the register list now.
    OS << "  // " << Name << " Register Class...\n"
       << "  const uint16_t " << Name
       << "[] = {\n    ";
    for (unsigned i = 0, e = Order.size(); i != e; ++i) {
      Record *Reg = Order[i];
      OS << getQualifiedName(Reg) << ", ";
    }
    OS << "\n  };\n\n";

    OS << "  // " << Name << " Bit set.\n"
       << "  const uint8_t " << Name
       << "Bits[] = {\n    ";
    BitVectorEmitter BVE;
    for (unsigned i = 0, e = Order.size(); i != e; ++i) {
      Record *Reg = Order[i];
      BVE.add(Target.getRegBank().getReg(Reg)->EnumValue);
    }
    BVE.print(OS);
    OS << "\n  };\n\n";

  }
  OS << "}\n\n";

  OS << "extern const MCRegisterClass " << TargetName
     << "MCRegisterClasses[] = {\n";

  for (unsigned rc = 0, e = RegisterClasses.size(); rc != e; ++rc) {
    const CodeGenRegisterClass &RC = *RegisterClasses[rc];

    // Asserts to make sure values will fit in table assuming types from
    // MCRegisterInfo.h
    assert((RC.SpillSize/8) <= 0xffff && "SpillSize too large.");
    assert((RC.SpillAlignment/8) <= 0xffff && "SpillAlignment too large.");
    assert(RC.CopyCost >= -128 && RC.CopyCost <= 127 && "Copy cost too large.");

    OS << "  { " << '\"' << RC.getName() << "\", "
       << RC.getName() << ", " << RC.getName() << "Bits, "
       << RC.getOrder().size() << ", sizeof(" << RC.getName() << "Bits), "
       << RC.getQualifiedName() + "RegClassID" << ", "
       << RC.SpillSize/8 << ", "
       << RC.SpillAlignment/8 << ", "
       << RC.CopyCost << ", "
       << RC.Allocatable << " },\n";
  }

  OS << "};\n\n";

  // Emit the data table for getSubReg().
  ArrayRef<CodeGenSubRegIndex*> SubRegIndices = RegBank.getSubRegIndices();
  if (SubRegIndices.size()) {
    OS << "const uint16_t " << TargetName << "SubRegTable[]["
       << SubRegIndices.size() << "] = {\n";
    for (unsigned i = 0, e = Regs.size(); i != e; ++i) {
      const CodeGenRegister::SubRegMap &SRM = Regs[i]->getSubRegs();
      OS << "  /* " << Regs[i]->TheDef->getName() << " */\n";
      if (SRM.empty()) {
        OS << "  {0},\n";
        continue;
      }
      OS << "  {";
      for (unsigned j = 0, je = SubRegIndices.size(); j != je; ++j) {
        // FIXME: We really should keep this to 80 columns...
        CodeGenRegister::SubRegMap::const_iterator SubReg =
          SRM.find(SubRegIndices[j]);
        if (SubReg != SRM.end())
          OS << getQualifiedName(SubReg->second->TheDef);
        else
          OS << "0";
        if (j != je - 1)
          OS << ", ";
      }
      OS << "}" << (i != e ? "," : "") << "\n";
    }
    OS << "};\n\n";
    OS << "const uint16_t *get" << TargetName
       << "SubRegTable() {\n  return (const uint16_t *)" << TargetName
       << "SubRegTable;\n}\n\n";
  }

  EmitRegMappingTables(OS, Regs, false);

  // Emit Reg encoding table
  OS << "extern const uint16_t " << TargetName;
  OS << "RegEncodingTable[] = {\n";
  // Add entry for NoRegister
  OS << "  0,\n";
  for (unsigned i = 0, e = Regs.size(); i != e; ++i) {
    Record *Reg = Regs[i]->TheDef;
    BitsInit *BI = Reg->getValueAsBitsInit("HWEncoding");
    uint64_t Value = 0;
    for (unsigned b = 0, be = BI->getNumBits(); b != be; ++b) {
      if (BitInit *B = dynamic_cast<BitInit*>(BI->getBit(b)))
      Value |= (uint64_t)B->getValue() << b;
    }
    OS << "  " << Value << ",\n";
  }
  OS << "};\n";       // End of HW encoding table

  // MCRegisterInfo initialization routine.
  OS << "static inline void Init" << TargetName
     << "MCRegisterInfo(MCRegisterInfo *RI, unsigned RA, "
     << "unsigned DwarfFlavour = 0, unsigned EHFlavour = 0) {\n";
  OS << "  RI->InitMCRegisterInfo(" << TargetName << "RegDesc, "
     << Regs.size()+1 << ", RA, " << TargetName << "MCRegisterClasses, "
     << RegisterClasses.size() << ", " << TargetName << "RegLists, ";
  if (SubRegIndices.size() != 0)
    OS << "(uint16_t*)" << TargetName << "SubRegTable, "
       << SubRegIndices.size() << ",\n";
  else
    OS << "NULL, 0,\n";

  OS << "  " << TargetName << "RegEncodingTable);\n\n";

  EmitRegMapping(OS, Regs, false);

  OS << "}\n\n";

  OS << "} // End llvm namespace \n";
  OS << "#endif // GET_REGINFO_MC_DESC\n\n";
}
void InstrInfoEmitter::emitRecord(const CodeGenInstruction &Inst, unsigned Num,
                                  Record *InstrInfo,
                         std::map<std::vector<Record*>, unsigned> &EmittedLists,
                                  const OperandInfoMapTy &OpInfo,
                                  raw_ostream &OS) {
  int MinOperands = 0;
  if (!Inst.Operands.empty())
    // Each logical operand can be multiple MI operands.
    MinOperands = Inst.Operands.back().MIOperandNo +
                  Inst.Operands.back().MINumOperands;

  OS << "  { ";
  OS << Num << ",\t" << MinOperands << ",\t"
     << Inst.Operands.NumDefs << ",\t"
     << Inst.TheDef->getValueAsInt("Size") << ",\t"
     << SchedModels.getSchedClassIdx(Inst) << ",\t0";

  // Emit all of the target independent flags...
  if (Inst.isPseudo)           OS << "|(1ULL<<MCID::Pseudo)";
  if (Inst.isReturn)           OS << "|(1ULL<<MCID::Return)";
  if (Inst.isBranch)           OS << "|(1ULL<<MCID::Branch)";
  if (Inst.isIndirectBranch)   OS << "|(1ULL<<MCID::IndirectBranch)";
  if (Inst.isCompare)          OS << "|(1ULL<<MCID::Compare)";
  if (Inst.isMoveImm)          OS << "|(1ULL<<MCID::MoveImm)";
  if (Inst.isBitcast)          OS << "|(1ULL<<MCID::Bitcast)";
  if (Inst.isSelect)           OS << "|(1ULL<<MCID::Select)";
  if (Inst.isBarrier)          OS << "|(1ULL<<MCID::Barrier)";
  if (Inst.hasDelaySlot)       OS << "|(1ULL<<MCID::DelaySlot)";
  if (Inst.isCall)             OS << "|(1ULL<<MCID::Call)";
  if (Inst.canFoldAsLoad)      OS << "|(1ULL<<MCID::FoldableAsLoad)";
  if (Inst.mayLoad)            OS << "|(1ULL<<MCID::MayLoad)";
  if (Inst.mayStore)           OS << "|(1ULL<<MCID::MayStore)";
  if (Inst.isPredicable)       OS << "|(1ULL<<MCID::Predicable)";
  if (Inst.isConvertibleToThreeAddress) OS << "|(1ULL<<MCID::ConvertibleTo3Addr)";
  if (Inst.isCommutable)       OS << "|(1ULL<<MCID::Commutable)";
  if (Inst.isTerminator)       OS << "|(1ULL<<MCID::Terminator)";
  if (Inst.isReMaterializable) OS << "|(1ULL<<MCID::Rematerializable)";
  if (Inst.isNotDuplicable)    OS << "|(1ULL<<MCID::NotDuplicable)";
  if (Inst.Operands.hasOptionalDef) OS << "|(1ULL<<MCID::HasOptionalDef)";
  if (Inst.usesCustomInserter) OS << "|(1ULL<<MCID::UsesCustomInserter)";
  if (Inst.hasPostISelHook)    OS << "|(1ULL<<MCID::HasPostISelHook)";
  if (Inst.Operands.isVariadic)OS << "|(1ULL<<MCID::Variadic)";
  if (Inst.hasSideEffects)     OS << "|(1ULL<<MCID::UnmodeledSideEffects)";
  if (Inst.isAsCheapAsAMove)   OS << "|(1ULL<<MCID::CheapAsAMove)";
  if (Inst.hasExtraSrcRegAllocReq) OS << "|(1ULL<<MCID::ExtraSrcRegAllocReq)";
  if (Inst.hasExtraDefRegAllocReq) OS << "|(1ULL<<MCID::ExtraDefRegAllocReq)";
  if (Inst.isRegSequence) OS << "|(1ULL<<MCID::RegSequence)";
  if (Inst.isExtractSubreg) OS << "|(1ULL<<MCID::ExtractSubreg)";
  if (Inst.isInsertSubreg) OS << "|(1ULL<<MCID::InsertSubreg)";
  if (Inst.isConvergent) OS << "|(1ULL<<MCID::Convergent)";

  // Emit all of the target-specific flags...
  BitsInit *TSF = Inst.TheDef->getValueAsBitsInit("TSFlags");
  if (!TSF)
    PrintFatalError("no TSFlags?");
  uint64_t Value = 0;
  for (unsigned i = 0, e = TSF->getNumBits(); i != e; ++i) {
    if (BitInit *Bit = dyn_cast<BitInit>(TSF->getBit(i)))
      Value |= uint64_t(Bit->getValue()) << i;
    else
      PrintFatalError("Invalid TSFlags bit in " + Inst.TheDef->getName());
  }
  OS << ", 0x";
  OS.write_hex(Value);
  OS << "ULL, ";

  // Emit the implicit uses and defs lists...
  std::vector<Record*> UseList = Inst.TheDef->getValueAsListOfDefs("Uses");
  if (UseList.empty())
    OS << "nullptr, ";
  else
    OS << "ImplicitList" << EmittedLists[UseList] << ", ";

  std::vector<Record*> DefList = Inst.TheDef->getValueAsListOfDefs("Defs");
  if (DefList.empty())
    OS << "nullptr, ";
  else
    OS << "ImplicitList" << EmittedLists[DefList] << ", ";

  // Emit the operand info.
  std::vector<std::string> OperandInfo = GetOperandInfo(Inst);
  if (OperandInfo.empty())
    OS << "nullptr";
  else
    OS << "OperandInfo" << OpInfo.find(OperandInfo)->second;

  CodeGenTarget &Target = CDP.getTargetInfo();
  if (Inst.HasComplexDeprecationPredicate)
    // Emit a function pointer to the complex predicate method.
    OS << ", -1 "
       << ",&get" << Inst.DeprecatedReason << "DeprecationInfo";
  else if (!Inst.DeprecatedReason.empty())
    // Emit the Subtarget feature.
    OS << ", " << Target.getInstNamespace() << "::" << Inst.DeprecatedReason
       << " ,nullptr";
  else
    // Instruction isn't deprecated.
    OS << ", -1 ,nullptr";

  OS << " },  // Inst #" << Num << " = " << Inst.TheDef->getName() << "\n";
}
//
// runMCDesc - Print out MC register descriptions.
//
void
RegisterInfoEmitter::runMCDesc(raw_ostream &OS, CodeGenTarget &Target,
                               CodeGenRegBank &RegBank) {
  emitSourceFileHeader("MC Register Information", OS);

  OS << "\n#ifdef GET_REGINFO_MC_DESC\n";
  OS << "#undef GET_REGINFO_MC_DESC\n";

  const std::vector<CodeGenRegister*> &Regs = RegBank.getRegisters();

  // The lists of sub-registers, super-registers, and overlaps all go in the
  // same array. That allows us to share suffixes.
  typedef std::vector<const CodeGenRegister*> RegVec;

  // Differentially encoded lists.
  SequenceToOffsetTable<DiffVec> DiffSeqs;
  SmallVector<DiffVec, 4> SubRegLists(Regs.size());
  SmallVector<DiffVec, 4> SuperRegLists(Regs.size());
  SmallVector<DiffVec, 4> OverlapLists(Regs.size());
  SmallVector<DiffVec, 4> RegUnitLists(Regs.size());
  SmallVector<unsigned, 4> RegUnitInitScale(Regs.size());

  // Keep track of sub-register names as well. These are not differentially
  // encoded.
  typedef SmallVector<const CodeGenSubRegIndex*, 4> SubRegIdxVec;
  SequenceToOffsetTable<SubRegIdxVec> SubRegIdxSeqs;
  SmallVector<SubRegIdxVec, 4> SubRegIdxLists(Regs.size());

  SequenceToOffsetTable<std::string> RegStrings;

  // Precompute register lists for the SequenceToOffsetTable.
  for (unsigned i = 0, e = Regs.size(); i != e; ++i) {
    const CodeGenRegister *Reg = Regs[i];

    RegStrings.add(Reg->getName());

    // Compute the ordered sub-register list.
    SetVector<const CodeGenRegister*> SR;
    Reg->addSubRegsPreOrder(SR, RegBank);
    diffEncode(SubRegLists[i], Reg->EnumValue, SR.begin(), SR.end());
    DiffSeqs.add(SubRegLists[i]);

    // Compute the corresponding sub-register indexes.
    SubRegIdxVec &SRIs = SubRegIdxLists[i];
    for (unsigned j = 0, je = SR.size(); j != je; ++j)
      SRIs.push_back(Reg->getSubRegIndex(SR[j]));
    SubRegIdxSeqs.add(SRIs);

    // Super-registers are already computed.
    const RegVec &SuperRegList = Reg->getSuperRegs();
    diffEncode(SuperRegLists[i], Reg->EnumValue,
               SuperRegList.begin(), SuperRegList.end());
    DiffSeqs.add(SuperRegLists[i]);

    // The list of overlaps doesn't need to have any particular order, and Reg
    // itself must be omitted.
    DiffVec &OverlapList = OverlapLists[i];
    CodeGenRegister::Set OSet;
    Reg->computeOverlaps(OSet, RegBank);
    OSet.erase(Reg);
    diffEncode(OverlapList, Reg->EnumValue, OSet.begin(), OSet.end());
    DiffSeqs.add(OverlapList);

    // Differentially encode the register unit list, seeded by register number.
    // First compute a scale factor that allows more diff-lists to be reused:
    //
    //   D0 -> (S0, S1)
    //   D1 -> (S2, S3)
    //
    // A scale factor of 2 allows D0 and D1 to share a diff-list. The initial
    // value for the differential decoder is the register number multiplied by
    // the scale.
    //
    // Check the neighboring registers for arithmetic progressions.
    unsigned ScaleA = ~0u, ScaleB = ~0u;
    ArrayRef<unsigned> RUs = Reg->getNativeRegUnits();
    if (i > 0 && Regs[i-1]->getNativeRegUnits().size() == RUs.size())
      ScaleB = RUs.front() - Regs[i-1]->getNativeRegUnits().front();
    if (i+1 != Regs.size() &&
        Regs[i+1]->getNativeRegUnits().size() == RUs.size())
      ScaleA = Regs[i+1]->getNativeRegUnits().front() - RUs.front();
    unsigned Scale = std::min(ScaleB, ScaleA);
    // Default the scale to 0 if it can't be encoded in 4 bits.
    if (Scale >= 16)
      Scale = 0;
    RegUnitInitScale[i] = Scale;
    DiffSeqs.add(diffEncode(RegUnitLists[i], Scale * Reg->EnumValue, RUs));
  }

  // Compute the final layout of the sequence table.
  DiffSeqs.layout();
  SubRegIdxSeqs.layout();

  OS << "namespace llvm {\n\n";

  const std::string &TargetName = Target.getName();

  // Emit the shared table of differential lists.
  OS << "extern const uint16_t " << TargetName << "RegDiffLists[] = {\n";
  DiffSeqs.emit(OS, printDiff16);
  OS << "};\n\n";

  // Emit the table of sub-register indexes.
  OS << "extern const uint16_t " << TargetName << "SubRegIdxLists[] = {\n";
  SubRegIdxSeqs.emit(OS, printSubRegIndex);
  OS << "};\n\n";

  // Emit the string table.
  RegStrings.layout();
  OS << "extern const char " << TargetName << "RegStrings[] = {\n";
  RegStrings.emit(OS, printChar);
  OS << "};\n\n";

  OS << "extern const MCRegisterDesc " << TargetName
     << "RegDesc[] = { // Descriptors\n";
  OS << "  { " << RegStrings.get("") << ", 0, 0, 0, 0, 0 },\n";

  // Emit the register descriptors now.
  for (unsigned i = 0, e = Regs.size(); i != e; ++i) {
    const CodeGenRegister *Reg = Regs[i];
    OS << "  { " << RegStrings.get(Reg->getName()) << ", "
       << DiffSeqs.get(OverlapLists[i]) << ", "
       << DiffSeqs.get(SubRegLists[i]) << ", "
       << DiffSeqs.get(SuperRegLists[i]) << ", "
       << SubRegIdxSeqs.get(SubRegIdxLists[i]) << ", "
       << (DiffSeqs.get(RegUnitLists[i])*16 + RegUnitInitScale[i]) << " },\n";
  }
  OS << "};\n\n";      // End of register descriptors...

  // Emit the table of register unit roots. Each regunit has one or two root
  // registers.
  OS << "extern const uint16_t " << TargetName << "RegUnitRoots[][2] = {\n";
  for (unsigned i = 0, e = RegBank.getNumNativeRegUnits(); i != e; ++i) {
    ArrayRef<const CodeGenRegister*> Roots = RegBank.getRegUnit(i).getRoots();
    assert(!Roots.empty() && "All regunits must have a root register.");
    assert(Roots.size() <= 2 && "More than two roots not supported yet.");
    OS << "  { " << getQualifiedName(Roots.front()->TheDef);
    for (unsigned r = 1; r != Roots.size(); ++r)
      OS << ", " << getQualifiedName(Roots[r]->TheDef);
    OS << " },\n";
  }
  OS << "};\n\n";

  ArrayRef<CodeGenRegisterClass*> RegisterClasses = RegBank.getRegClasses();

  // Loop over all of the register classes... emitting each one.
  OS << "namespace {     // Register classes...\n";

  // Emit the register enum value arrays for each RegisterClass
  for (unsigned rc = 0, e = RegisterClasses.size(); rc != e; ++rc) {
    const CodeGenRegisterClass &RC = *RegisterClasses[rc];
    ArrayRef<Record*> Order = RC.getOrder();

    // Give the register class a legal C name if it's anonymous.
    std::string Name = RC.getName();

    // Emit the register list now.
    OS << "  // " << Name << " Register Class...\n"
       << "  const uint16_t " << Name
       << "[] = {\n    ";
    for (unsigned i = 0, e = Order.size(); i != e; ++i) {
      Record *Reg = Order[i];
      OS << getQualifiedName(Reg) << ", ";
    }
    OS << "\n  };\n\n";

    OS << "  // " << Name << " Bit set.\n"
       << "  const uint8_t " << Name
       << "Bits[] = {\n    ";
    BitVectorEmitter BVE;
    for (unsigned i = 0, e = Order.size(); i != e; ++i) {
      Record *Reg = Order[i];
      BVE.add(Target.getRegBank().getReg(Reg)->EnumValue);
    }
    BVE.print(OS);
    OS << "\n  };\n\n";

  }
  OS << "}\n\n";

  OS << "extern const MCRegisterClass " << TargetName
     << "MCRegisterClasses[] = {\n";

  for (unsigned rc = 0, e = RegisterClasses.size(); rc != e; ++rc) {
    const CodeGenRegisterClass &RC = *RegisterClasses[rc];

    // Asserts to make sure values will fit in table assuming types from
    // MCRegisterInfo.h
    assert((RC.SpillSize/8) <= 0xffff && "SpillSize too large.");
    assert((RC.SpillAlignment/8) <= 0xffff && "SpillAlignment too large.");
    assert(RC.CopyCost >= -128 && RC.CopyCost <= 127 && "Copy cost too large.");

    OS << "  { " << '\"' << RC.getName() << "\", "
       << RC.getName() << ", " << RC.getName() << "Bits, "
       << RC.getOrder().size() << ", sizeof(" << RC.getName() << "Bits), "
       << RC.getQualifiedName() + "RegClassID" << ", "
       << RC.SpillSize/8 << ", "
       << RC.SpillAlignment/8 << ", "
       << RC.CopyCost << ", "
       << RC.Allocatable << " },\n";
  }

  OS << "};\n\n";

  ArrayRef<CodeGenSubRegIndex*> SubRegIndices = RegBank.getSubRegIndices();

  EmitRegMappingTables(OS, Regs, false);

  // Emit Reg encoding table
  OS << "extern const uint16_t " << TargetName;
  OS << "RegEncodingTable[] = {\n";
  // Add entry for NoRegister
  OS << "  0,\n";
  for (unsigned i = 0, e = Regs.size(); i != e; ++i) {
    Record *Reg = Regs[i]->TheDef;
    BitsInit *BI = Reg->getValueAsBitsInit("HWEncoding");
    uint64_t Value = 0;
    for (unsigned b = 0, be = BI->getNumBits(); b != be; ++b) {
      if (BitInit *B = dynamic_cast<BitInit*>(BI->getBit(b)))
      Value |= (uint64_t)B->getValue() << b;
    }
    OS << "  " << Value << ",\n";
  }
  OS << "};\n";       // End of HW encoding table

  // MCRegisterInfo initialization routine.
  OS << "static inline void Init" << TargetName
     << "MCRegisterInfo(MCRegisterInfo *RI, unsigned RA, "
     << "unsigned DwarfFlavour = 0, unsigned EHFlavour = 0) {\n"
     << "  RI->InitMCRegisterInfo(" << TargetName << "RegDesc, "
     << Regs.size()+1 << ", RA, " << TargetName << "MCRegisterClasses, "
     << RegisterClasses.size() << ", "
     << TargetName << "RegUnitRoots, "
     << RegBank.getNumNativeRegUnits() << ", "
     << TargetName << "RegDiffLists, "
     << TargetName << "RegStrings, "
     << TargetName << "SubRegIdxLists, "
     << SubRegIndices.size() << ",\n"
     << "  " << TargetName << "RegEncodingTable);\n\n";

  EmitRegMapping(OS, Regs, false);

  OS << "}\n\n";

  OS << "} // End llvm namespace \n";
  OS << "#endif // GET_REGINFO_MC_DESC\n\n";
}
Beispiel #8
0
/// SetValue -
/// Return true on error, false on success.
bool TGParser::SetValue(Record *CurRec, TGLoc Loc, const std::string &ValName, 
                        const std::vector<unsigned> &BitList, Init *V) {
  if (!V) return false;

  if (CurRec == 0) CurRec = &CurMultiClass->Rec;

  RecordVal *RV = CurRec->getValue(ValName);
  if (RV == 0)
    return Error(Loc, "Value '" + ValName + "' unknown!");

  // Do not allow assignments like 'X = X'.  This will just cause infinite loops
  // in the resolution machinery.
  if (BitList.empty())
    if (VarInit *VI = dynamic_cast<VarInit*>(V))
      if (VI->getName() == ValName)
        return false;
  
  // If we are assigning to a subset of the bits in the value... then we must be
  // assigning to a field of BitsRecTy, which must have a BitsInit
  // initializer.
  //
  if (!BitList.empty()) {
    BitsInit *CurVal = dynamic_cast<BitsInit*>(RV->getValue());
    if (CurVal == 0)
      return Error(Loc, "Value '" + ValName + "' is not a bits type");

    // Convert the incoming value to a bits type of the appropriate size...
    Init *BI = V->convertInitializerTo(new BitsRecTy(BitList.size()));
    if (BI == 0) {
      V->convertInitializerTo(new BitsRecTy(BitList.size()));
      return Error(Loc, "Initializer is not compatible with bit range");
    }
                   
    // We should have a BitsInit type now.
    BitsInit *BInit = dynamic_cast<BitsInit*>(BI);
    assert(BInit != 0);

    BitsInit *NewVal = new BitsInit(CurVal->getNumBits());

    // Loop over bits, assigning values as appropriate.
    for (unsigned i = 0, e = BitList.size(); i != e; ++i) {
      unsigned Bit = BitList[i];
      if (NewVal->getBit(Bit))
        return Error(Loc, "Cannot set bit #" + utostr(Bit) + " of value '" +
                     ValName + "' more than once");
      NewVal->setBit(Bit, BInit->getBit(i));
    }

    for (unsigned i = 0, e = CurVal->getNumBits(); i != e; ++i)
      if (NewVal->getBit(i) == 0)
        NewVal->setBit(i, CurVal->getBit(i));

    V = NewVal;
  }

  if (RV->setValue(V))
   return Error(Loc, "Value '" + ValName + "' of type '" + 
                RV->getType()->getAsString() + 
                "' is incompatible with initializer '" + V->getAsString() +"'");
  return false;
}
Beispiel #9
0
/// ParseSimpleValue - Parse a tblgen value.  This returns null on error.
///
///   SimpleValue ::= IDValue
///   SimpleValue ::= INTVAL
///   SimpleValue ::= STRVAL+
///   SimpleValue ::= CODEFRAGMENT
///   SimpleValue ::= '?'
///   SimpleValue ::= '{' ValueList '}'
///   SimpleValue ::= ID '<' ValueListNE '>'
///   SimpleValue ::= '[' ValueList ']'
///   SimpleValue ::= '(' IDValue DagArgList ')'
///   SimpleValue ::= CONCATTOK '(' Value ',' Value ')'
///   SimpleValue ::= SHLTOK '(' Value ',' Value ')'
///   SimpleValue ::= SRATOK '(' Value ',' Value ')'
///   SimpleValue ::= SRLTOK '(' Value ',' Value ')'
///   SimpleValue ::= STRCONCATTOK '(' Value ',' Value ')'
///
Init *TGParser::ParseSimpleValue(Record *CurRec) {
  Init *R = 0;
  switch (Lex.getCode()) {
  default: TokError("Unknown token when parsing a value"); break;
  case tgtok::IntVal: R = new IntInit(Lex.getCurIntVal()); Lex.Lex(); break;
  case tgtok::StrVal: {
    std::string Val = Lex.getCurStrVal();
    Lex.Lex();
    
    // Handle multiple consecutive concatenated strings.
    while (Lex.getCode() == tgtok::StrVal) {
      Val += Lex.getCurStrVal();
      Lex.Lex();
    }
    
    R = new StringInit(Val);
    break;
  }
  case tgtok::CodeFragment:
      R = new CodeInit(Lex.getCurStrVal()); Lex.Lex(); break;
  case tgtok::question: R = new UnsetInit(); Lex.Lex(); break;
  case tgtok::Id: {
    TGLoc NameLoc = Lex.getLoc();
    std::string Name = Lex.getCurStrVal();
    if (Lex.Lex() != tgtok::less)  // consume the Id.
      return ParseIDValue(CurRec, Name, NameLoc);    // Value ::= IDValue
    
    // Value ::= ID '<' ValueListNE '>'
    if (Lex.Lex() == tgtok::greater) {
      TokError("expected non-empty value list");
      return 0;
    }
    std::vector<Init*> ValueList = ParseValueList(CurRec);
    if (ValueList.empty()) return 0;
    
    if (Lex.getCode() != tgtok::greater) {
      TokError("expected '>' at end of value list");
      return 0;
    }
    Lex.Lex();  // eat the '>'
    
    // This is a CLASS<initvalslist> expression.  This is supposed to synthesize
    // a new anonymous definition, deriving from CLASS<initvalslist> with no
    // body.
    Record *Class = Records.getClass(Name);
    if (!Class) {
      Error(NameLoc, "Expected a class name, got '" + Name + "'");
      return 0;
    }
    
    // Create the new record, set it as CurRec temporarily.
    static unsigned AnonCounter = 0;
    Record *NewRec = new Record("anonymous.val."+utostr(AnonCounter++),NameLoc);
    SubClassReference SCRef;
    SCRef.RefLoc = NameLoc;
    SCRef.Rec = Class;
    SCRef.TemplateArgs = ValueList;
    // Add info about the subclass to NewRec.
    if (AddSubClass(NewRec, SCRef))
      return 0;
    NewRec->resolveReferences();
    Records.addDef(NewRec);
    
    // The result of the expression is a reference to the new record.
    return new DefInit(NewRec);
  }    
  case tgtok::l_brace: {           // Value ::= '{' ValueList '}'
    TGLoc BraceLoc = Lex.getLoc();
    Lex.Lex(); // eat the '{'
    std::vector<Init*> Vals;
    
    if (Lex.getCode() != tgtok::r_brace) {
      Vals = ParseValueList(CurRec);
      if (Vals.empty()) return 0;
    }
    if (Lex.getCode() != tgtok::r_brace) {
      TokError("expected '}' at end of bit list value");
      return 0;
    }
    Lex.Lex();  // eat the '}'
    
    BitsInit *Result = new BitsInit(Vals.size());
    for (unsigned i = 0, e = Vals.size(); i != e; ++i) {
      Init *Bit = Vals[i]->convertInitializerTo(new BitRecTy());
      if (Bit == 0) {
        Error(BraceLoc, "Element #" + utostr(i) + " (" + Vals[i]->getAsString()+
              ") is not convertable to a bit");
        return 0;
      }
      Result->setBit(Vals.size()-i-1, Bit);
    }
    return Result;
  }
  case tgtok::l_square: {          // Value ::= '[' ValueList ']'
    Lex.Lex(); // eat the '['
    std::vector<Init*> Vals;
    
    if (Lex.getCode() != tgtok::r_square) {
      Vals = ParseValueList(CurRec);
      if (Vals.empty()) return 0;
    }
    if (Lex.getCode() != tgtok::r_square) {
      TokError("expected ']' at end of list value");
      return 0;
    }
    Lex.Lex();  // eat the ']'
    return new ListInit(Vals);
  }
  case tgtok::l_paren: {         // Value ::= '(' IDValue DagArgList ')'
    Lex.Lex();   // eat the '('
    if (Lex.getCode() != tgtok::Id) {
      TokError("expected identifier in dag init");
      return 0;
    }
    
    Init *Operator = ParseIDValue(CurRec);
    if (Operator == 0) return 0;
    
    // If the operator name is present, parse it.
    std::string OperatorName;
    if (Lex.getCode() == tgtok::colon) {
      if (Lex.Lex() != tgtok::VarName) { // eat the ':'
        TokError("expected variable name in dag operator");
        return 0;
      }
      OperatorName = Lex.getCurStrVal();
      Lex.Lex();  // eat the VarName.
    }
    
    
    std::vector<std::pair<llvm::Init*, std::string> > DagArgs;
    if (Lex.getCode() != tgtok::r_paren) {
      DagArgs = ParseDagArgList(CurRec);
      if (DagArgs.empty()) return 0;
    }
    
    if (Lex.getCode() != tgtok::r_paren) {
      TokError("expected ')' in dag init");
      return 0;
    }
    Lex.Lex();  // eat the ')'
    
    return new DagInit(Operator, OperatorName, DagArgs);
  }
  case tgtok::XConcat:
  case tgtok::XSRA: 
  case tgtok::XSRL:
  case tgtok::XSHL:
  case tgtok::XStrConcat: {  // Value ::= !binop '(' Value ',' Value ')'
    BinOpInit::BinaryOp Code;
    switch (Lex.getCode()) {
    default: assert(0 && "Unhandled code!");
    case tgtok::XConcat:    Code = BinOpInit::CONCAT; break;
    case tgtok::XSRA:       Code = BinOpInit::SRA; break;
    case tgtok::XSRL:       Code = BinOpInit::SRL; break;
    case tgtok::XSHL:       Code = BinOpInit::SHL; break;
    case tgtok::XStrConcat: Code = BinOpInit::STRCONCAT; break;
    }
    Lex.Lex();  // eat the operation
    if (Lex.getCode() != tgtok::l_paren) {
      TokError("expected '(' after binary operator");
      return 0;
    }
    Lex.Lex();  // eat the '('
    
    Init *LHS = ParseValue(CurRec);
    if (LHS == 0) return 0;

    if (Lex.getCode() != tgtok::comma) {
      TokError("expected ',' in binary operator");
      return 0;
    }
    Lex.Lex();  // eat the ','
    
    Init *RHS = ParseValue(CurRec);
    if (RHS == 0) return 0;

    if (Lex.getCode() != tgtok::r_paren) {
      TokError("expected ')' in binary operator");
      return 0;
    }
    Lex.Lex();  // eat the ')'
    return (new BinOpInit(Code, LHS, RHS))->Fold();
  }
  }
  
  return R;
}
void InstrInfoEmitter::emitRecord(const CodeGenInstruction &Inst, unsigned Num,
                                  Record *InstrInfo,
                         std::map<std::vector<Record*>, unsigned> &EmittedLists,
                                  const OperandInfoMapTy &OpInfo,
                                  raw_ostream &OS) {
  int MinOperands = 0;
  if (!Inst.Operands.size() == 0)
    // Each logical operand can be multiple MI operands.
    MinOperands = Inst.Operands.back().MIOperandNo +
                  Inst.Operands.back().MINumOperands;

  OS << "  { ";
  OS << Num << ",\t" << MinOperands << ",\t"
     << Inst.Operands.NumDefs << ",\t"
     << getItinClassNumber(Inst.TheDef) << ",\t"
     << Inst.TheDef->getValueAsInt("Size") << ",\t0";

  // Emit all of the target indepedent flags...
  if (Inst.isPseudo)           OS << "|(1<<MCID::Pseudo)";
  if (Inst.isReturn)           OS << "|(1<<MCID::Return)";
  if (Inst.isBranch)           OS << "|(1<<MCID::Branch)";
  if (Inst.isIndirectBranch)   OS << "|(1<<MCID::IndirectBranch)";
  if (Inst.isCompare)          OS << "|(1<<MCID::Compare)";
  if (Inst.isMoveImm)          OS << "|(1<<MCID::MoveImm)";
  if (Inst.isBitcast)          OS << "|(1<<MCID::Bitcast)";
  if (Inst.isBarrier)          OS << "|(1<<MCID::Barrier)";
  if (Inst.hasDelaySlot)       OS << "|(1<<MCID::DelaySlot)";
  if (Inst.isCall)             OS << "|(1<<MCID::Call)";
  if (Inst.canFoldAsLoad)      OS << "|(1<<MCID::FoldableAsLoad)";
  if (Inst.mayLoad)            OS << "|(1<<MCID::MayLoad)";
  if (Inst.mayStore)           OS << "|(1<<MCID::MayStore)";
  if (Inst.isPredicable)       OS << "|(1<<MCID::Predicable)";
  if (Inst.isConvertibleToThreeAddress) OS << "|(1<<MCID::ConvertibleTo3Addr)";
  if (Inst.isCommutable)       OS << "|(1<<MCID::Commutable)";
  if (Inst.isTerminator)       OS << "|(1<<MCID::Terminator)";
  if (Inst.isReMaterializable) OS << "|(1<<MCID::Rematerializable)";
  if (Inst.isNotDuplicable)    OS << "|(1<<MCID::NotDuplicable)";
  if (Inst.Operands.hasOptionalDef) OS << "|(1<<MCID::HasOptionalDef)";
  if (Inst.usesCustomInserter) OS << "|(1<<MCID::UsesCustomInserter)";
  if (Inst.hasPostISelHook)    OS << "|(1<<MCID::HasPostISelHook)";
  if (Inst.Operands.isVariadic)OS << "|(1<<MCID::Variadic)";
  if (Inst.hasSideEffects)     OS << "|(1<<MCID::UnmodeledSideEffects)";
  if (Inst.isAsCheapAsAMove)   OS << "|(1<<MCID::CheapAsAMove)";
  if (Inst.hasExtraSrcRegAllocReq) OS << "|(1<<MCID::ExtraSrcRegAllocReq)";
  if (Inst.hasExtraDefRegAllocReq) OS << "|(1<<MCID::ExtraDefRegAllocReq)";

  // Emit all of the target-specific flags...
  BitsInit *TSF = Inst.TheDef->getValueAsBitsInit("TSFlags");
  if (!TSF) throw "no TSFlags?";
  uint64_t Value = 0;
  for (unsigned i = 0, e = TSF->getNumBits(); i != e; ++i) {
    if (BitInit *Bit = dynamic_cast<BitInit*>(TSF->getBit(i)))
      Value |= uint64_t(Bit->getValue()) << i;
    else
      throw "Invalid TSFlags bit in " + Inst.TheDef->getName();
  }
  OS << ", 0x";
  OS.write_hex(Value);
  OS << "ULL, ";

  // Emit the implicit uses and defs lists...
  std::vector<Record*> UseList = Inst.TheDef->getValueAsListOfDefs("Uses");
  if (UseList.empty())
    OS << "NULL, ";
  else
    OS << "ImplicitList" << EmittedLists[UseList] << ", ";

  std::vector<Record*> DefList = Inst.TheDef->getValueAsListOfDefs("Defs");
  if (DefList.empty())
    OS << "NULL, ";
  else
    OS << "ImplicitList" << EmittedLists[DefList] << ", ";

  // Emit the operand info.
  std::vector<std::string> OperandInfo = GetOperandInfo(Inst);
  if (OperandInfo.empty())
    OS << "0";
  else
    OS << "OperandInfo" << OpInfo.find(OperandInfo)->second;

  OS << " },  // Inst #" << Num << " = " << Inst.TheDef->getName() << "\n";
}
Beispiel #11
0
void CodeEmitterGen::run(raw_ostream &o) {
  CodeGenTarget Target;
  std::vector<Record*> Insts = Records.getAllDerivedDefinitions("Instruction");
  
  // For little-endian instruction bit encodings, reverse the bit order
  if (Target.isLittleEndianEncoding()) reverseBits(Insts);

  EmitSourceFileHeader("Machine Code Emitter", o);
  std::string Namespace = Insts[0]->getValueAsString("Namespace") + "::";
  
  std::vector<const CodeGenInstruction*> NumberedInstructions;
  Target.getInstructionsByEnumValue(NumberedInstructions);

  // Emit function declaration
  o << "unsigned " << Target.getName() << "CodeEmitter::"
    << "getBinaryCodeForInstr(const MachineInstr &MI) {\n";

  // Emit instruction base values
  o << "  static const unsigned InstBits[] = {\n";
  for (std::vector<const CodeGenInstruction*>::iterator
          IN = NumberedInstructions.begin(),
          EN = NumberedInstructions.end();
       IN != EN; ++IN) {
    const CodeGenInstruction *CGI = *IN;
    Record *R = CGI->TheDef;
    
    if (R->getName() == "PHI" ||
        R->getName() == "INLINEASM" ||
        R->getName() == "DBG_LABEL" ||
        R->getName() == "EH_LABEL" ||
        R->getName() == "GC_LABEL" ||
        R->getName() == "KILL" ||
        R->getName() == "EXTRACT_SUBREG" ||
        R->getName() == "INSERT_SUBREG" ||
        R->getName() == "IMPLICIT_DEF" ||
        R->getName() == "SUBREG_TO_REG" ||
        R->getName() == "COPY_TO_REGCLASS") {
      o << "    0U,\n";
      continue;
    }
    
    BitsInit *BI = R->getValueAsBitsInit("Inst");

    // Start by filling in fixed values...
    unsigned Value = 0;
    for (unsigned i = 0, e = BI->getNumBits(); i != e; ++i) {
      if (BitInit *B = dynamic_cast<BitInit*>(BI->getBit(e-i-1))) {
        Value |= B->getValue() << (e-i-1);
      }
    }
    o << "    " << Value << "U," << '\t' << "// " << R->getName() << "\n";
  }
  o << "    0U\n  };\n";
  
  // Map to accumulate all the cases.
  std::map<std::string, std::vector<std::string> > CaseMap;
  
  // Construct all cases statement for each opcode
  for (std::vector<Record*>::iterator IC = Insts.begin(), EC = Insts.end();
        IC != EC; ++IC) {
    Record *R = *IC;
    const std::string &InstName = R->getName();
    std::string Case("");
    
    if (InstName == "PHI" ||
        InstName == "INLINEASM" ||
        InstName == "DBG_LABEL"||
        InstName == "EH_LABEL"||
        InstName == "GC_LABEL"||
        InstName == "KILL"||
        InstName == "EXTRACT_SUBREG" ||
        InstName == "INSERT_SUBREG" ||
        InstName == "IMPLICIT_DEF" ||
        InstName == "SUBREG_TO_REG" ||
        InstName == "COPY_TO_REGCLASS") continue;

    BitsInit *BI = R->getValueAsBitsInit("Inst");
    const std::vector<RecordVal> &Vals = R->getValues();
    CodeGenInstruction &CGI = Target.getInstruction(InstName);
    
    // Loop over all of the fields in the instruction, determining which are the
    // operands to the instruction.
    unsigned op = 0;
    for (unsigned i = 0, e = Vals.size(); i != e; ++i) {
      if (!Vals[i].getPrefix() && !Vals[i].getValue()->isComplete()) {
        // Is the operand continuous? If so, we can just mask and OR it in
        // instead of doing it bit-by-bit, saving a lot in runtime cost.
        const std::string &VarName = Vals[i].getName();
        bool gotOp = false;
        
        for (int bit = BI->getNumBits()-1; bit >= 0; ) {
          int varBit = getVariableBit(VarName, BI, bit);
          
          if (varBit == -1) {
            --bit;
          } else {
            int beginInstBit = bit;
            int beginVarBit = varBit;
            int N = 1;
            
            for (--bit; bit >= 0;) {
              varBit = getVariableBit(VarName, BI, bit);
              if (varBit == -1 || varBit != (beginVarBit - N)) break;
              ++N;
              --bit;
            }

            if (!gotOp) {
              /// If this operand is not supposed to be emitted by the generated
              /// emitter, skip it.
              while (CGI.isFlatOperandNotEmitted(op))
                ++op;
              
              Case += "      // op: " + VarName + "\n"
                   +  "      op = getMachineOpValue(MI, MI.getOperand("
                   +  utostr(op++) + "));\n";
              gotOp = true;
            }
            
            unsigned opMask = ~0U >> (32-N);
            int opShift = beginVarBit - N + 1;
            opMask <<= opShift;
            opShift = beginInstBit - beginVarBit;
            
            if (opShift > 0) {
              Case += "      Value |= (op & " + utostr(opMask) + "U) << "
                   +  itostr(opShift) + ";\n";
            } else if (opShift < 0) {
              Case += "      Value |= (op & " + utostr(opMask) + "U) >> "
                   +  itostr(-opShift) + ";\n";
            } else {
              Case += "      Value |= op & " + utostr(opMask) + "U;\n";
            }
          }
        }
      }
    }

    std::vector<std::string> &InstList = CaseMap[Case];
    InstList.push_back(InstName);
  }


  // Emit initial function code
  o << "  const unsigned opcode = MI.getOpcode();\n"
    << "  unsigned Value = InstBits[opcode];\n"
    << "  unsigned op = 0;\n"
    << "  op = op;  // suppress warning\n"
    << "  switch (opcode) {\n";

  // Emit each case statement
  std::map<std::string, std::vector<std::string> >::iterator IE, EE;
  for (IE = CaseMap.begin(), EE = CaseMap.end(); IE != EE; ++IE) {
    const std::string &Case = IE->first;
    std::vector<std::string> &InstList = IE->second;

    for (int i = 0, N = InstList.size(); i < N; i++) {
      if (i) o << "\n";
      o << "    case " << Namespace << InstList[i]  << ":";
    }
    o << " {\n";
    o << Case;
    o << "      break;\n"
      << "    }\n";
  }

  // Default case: unhandled opcode
  o << "  default:\n"
    << "    std::string msg;\n"
    << "    raw_string_ostream Msg(msg);\n"
    << "    Msg << \"Not supported instr: \" << MI;\n"
    << "    llvm_report_error(Msg.str());\n"
    << "  }\n"
    << "  return Value;\n"
    << "}\n\n";
}
void CodeEmitterGen::run(std::ostream &o) {
  std::vector<Record*> Insts = Records.getAllDerivedDefinitions("Instruction");

  EmitSourceFileHeader("Machine Code Emitter", o);

  std::string Namespace = "V9::";
  std::string ClassName = "SparcV9CodeEmitter::";

  //const std::string &Namespace = Inst->getValue("Namespace")->getName();
  o << "unsigned " << ClassName
    << "getBinaryCodeForInstr(MachineInstr &MI) {\n"
    << "  unsigned Value = 0;\n"
    << "  DEBUG(std::cerr << MI);\n"
    << "  switch (MI.getOpcode()) {\n";
  for (std::vector<Record*>::iterator I = Insts.begin(), E = Insts.end();
       I != E; ++I) {
    Record *R = *I;
    o << "    case " << Namespace << R->getName() << ": {\n"
      << "      DEBUG(std::cerr << \"Emitting " << R->getName() << "\\n\");\n";

    BitsInit *BI = R->getValueAsBitsInit("Inst");

    unsigned Value = 0;
    const std::vector<RecordVal> &Vals = R->getValues();

    DEBUG(o << "      // prefilling: ");
    // Start by filling in fixed values...
    for (unsigned i = 0, e = BI->getNumBits(); i != e; ++i) {
      if (BitInit *B = dynamic_cast<BitInit*>(BI->getBit(e-i-1))) {
        Value |= B->getValue() << (e-i-1);
        DEBUG(o << B->getValue());
      } else {
        DEBUG(o << "0");
      }
    }
    DEBUG(o << "\n");

    DEBUG(o << "      // " << *R->getValue("Inst") << "\n");
    o << "      Value = " << Value << "U;\n\n";
    
    // Loop over all of the fields in the instruction determining which are the
    // operands to the instruction. 
    //
    unsigned op = 0;
    std::map<std::string, unsigned> OpOrder;
    std::map<std::string, bool> OpContinuous;
    for (unsigned i = 0, e = Vals.size(); i != e; ++i) {
      if (!Vals[i].getPrefix() &&  !Vals[i].getValue()->isComplete()) {
        // Is the operand continuous? If so, we can just mask and OR it in
        // instead of doing it bit-by-bit, saving a lot in runtime cost.        
        const BitsInit *InstInit = BI;
        int beginBitInVar = -1, endBitInVar = -1;
        int beginBitInInst = -1, endBitInInst = -1;
        bool continuous = true;

        for (int bit = InstInit->getNumBits()-1; bit >= 0; --bit) {
          if (VarBitInit *VBI =
              dynamic_cast<VarBitInit*>(InstInit->getBit(bit))) {
            TypedInit *TI = VBI->getVariable();
            if (VarInit *VI = dynamic_cast<VarInit*>(TI)) {
              // only process the current variable
              if (VI->getName() != Vals[i].getName())
                continue;

              if (beginBitInVar == -1)
                beginBitInVar = VBI->getBitNum();

              if (endBitInVar == -1)
                endBitInVar = VBI->getBitNum();
              else {
                if (endBitInVar == (int)VBI->getBitNum() + 1)
                  endBitInVar = VBI->getBitNum();
                else {
                  continuous = false;
                  break;
                }
              }

              if (beginBitInInst == -1)
                beginBitInInst = bit;
              if (endBitInInst == -1)
                endBitInInst = bit;
              else {
                if (endBitInInst == bit + 1)
                  endBitInInst = bit;
                else {
                  continuous = false;
                  break;
                }
              }

              // maintain same distance between bits in field and bits in
              // instruction. if the relative distances stay the same
              // throughout,
              if (beginBitInVar - (int)VBI->getBitNum() !=
                  beginBitInInst - bit) {
                continuous = false;
                break;
              }
            }
          }
        }

        // If we have found no bit in "Inst" which comes from this field, then
        // this is not an operand!!
        if (beginBitInInst != -1) {
          o << "      // op" << op << ": " << Vals[i].getName() << "\n"
            << "      int64_t op" << op 
            <<" = getMachineOpValue(MI, MI.getOperand("<<op<<"));\n";
          //<< "   MachineOperand &op" << op <<" = MI.getOperand("<<op<<");\n";
          OpOrder[Vals[i].getName()] = op++;
          
          DEBUG(o << "      // Var: begin = " << beginBitInVar 
                  << ", end = " << endBitInVar
                  << "; Inst: begin = " << beginBitInInst
                  << ", end = " << endBitInInst << "\n");
          
          if (continuous) {
            DEBUG(o << "      // continuous: op" << OpOrder[Vals[i].getName()]
                    << "\n");
            
            // Mask off the right bits
            // Low mask (ie. shift, if necessary)
            assert(endBitInVar >= 0 && "Negative shift amount in masking!");
            if (endBitInVar != 0) {
              o << "      op" << OpOrder[Vals[i].getName()]
                << " >>= " << endBitInVar << ";\n";
              beginBitInVar -= endBitInVar;
              endBitInVar = 0;
            }
            
            // High mask
            o << "      op" << OpOrder[Vals[i].getName()]
              << " &= (1<<" << beginBitInVar+1 << ") - 1;\n";
            
            // Shift the value to the correct place (according to place in inst)
            assert(endBitInInst >= 0 && "Negative shift amount!");
            if (endBitInInst != 0)
              o << "      op" << OpOrder[Vals[i].getName()]
              << " <<= " << endBitInInst << ";\n";
            
            // Just OR in the result
            o << "      Value |= op" << OpOrder[Vals[i].getName()] << ";\n";
          }
          
          // otherwise, will be taken care of in the loop below using this
          // value:
          OpContinuous[Vals[i].getName()] = continuous;
        }
      }
    }

    for (unsigned f = 0, e = Vals.size(); f != e; ++f) {
      if (Vals[f].getPrefix()) {
        BitsInit *FieldInitializer = (BitsInit*)Vals[f].getValue();

        // Scan through the field looking for bit initializers of the current
        // variable...
        for (int i = FieldInitializer->getNumBits()-1; i >= 0; --i) {
          if (BitInit *BI = dynamic_cast<BitInit*>(FieldInitializer->getBit(i)))
          {
            DEBUG(o << "      // bit init: f: " << f << ", i: " << i << "\n");
          } else if (UnsetInit *UI =
                     dynamic_cast<UnsetInit*>(FieldInitializer->getBit(i))) {
            DEBUG(o << "      // unset init: f: " << f << ", i: " << i << "\n");
          } else if (VarBitInit *VBI =
                     dynamic_cast<VarBitInit*>(FieldInitializer->getBit(i))) {
            TypedInit *TI = VBI->getVariable();
            if (VarInit *VI = dynamic_cast<VarInit*>(TI)) {
              // If the bits of the field are laid out consecutively in the
              // instruction, then instead of separately ORing in bits, just
              // mask and shift the entire field for efficiency.
              if (OpContinuous[VI->getName()]) {
                // already taken care of in the loop above, thus there is no
                // need to individually OR in the bits

                // for debugging, output the regular version anyway, commented
                DEBUG(o << "      // Value |= getValueBit(op"
                        << OpOrder[VI->getName()] << ", " << VBI->getBitNum()
                        << ")" << " << " << i << ";\n");
              } else {
                o << "      Value |= getValueBit(op" << OpOrder[VI->getName()]
                  << ", " << VBI->getBitNum()
                  << ")" << " << " << i << ";\n";
              }
            } else if (FieldInit *FI = dynamic_cast<FieldInit*>(TI)) {
              // FIXME: implement this!
              o << "FIELD INIT not implemented yet!\n";
            } else {
              o << "Error: UNIMPLEMENTED\n";
            }
          }
        }
      }
    }

    o << "      break;\n"
      << "    }\n";
  }

  o << "  default:\n"
    << "    std::cerr << \"Not supported instr: \" << MI << \"\\n\";\n"
    << "    abort();\n"
    << "  }\n"
    << "  return Value;\n"
    << "}\n";

  EmitSourceFileTail(o);
}