Ejemplo n.º 1
0
// runEnums - Print out enum values for all of the instructions.
void InstrEnumEmitter::run(std::ostream &OS) {
  EmitSourceFileHeader("Target Instruction Enum Values", OS);
  OS << "namespace llvm {\n\n";

  CodeGenTarget Target;

  // We must emit the PHI opcode first...
  std::string Namespace;
  for (CodeGenTarget::inst_iterator II = Target.inst_begin(), 
       E = Target.inst_end(); II != E; ++II) {
    if (II->second.Namespace != "TargetInstrInfo") {
      Namespace = II->second.Namespace;
      break;
    }
  }
  
  if (Namespace.empty()) {
    fprintf(stderr, "No instructions defined!\n");
    exit(1);
  }

  std::vector<const CodeGenInstruction*> NumberedInstructions;
  Target.getInstructionsByEnumValue(NumberedInstructions);

  OS << "namespace " << Namespace << " {\n";
  OS << "  enum {\n";
  for (unsigned i = 0, e = NumberedInstructions.size(); i != e; ++i) {
    OS << "    " << NumberedInstructions[i]->TheDef->getName()
       << "\t= " << i << ",\n";
  }
  OS << "    INSTRUCTION_LIST_END = " << NumberedInstructions.size() << "\n";
  OS << "  };\n}\n";
  OS << "} // End llvm namespace \n";
}
/// populateInstInfo - Fills an array of InstInfos with information about each
///   instruction in a target
///
/// @arg infoArray  - The array of InstInfo objects to populate
/// @arg target     - The CodeGenTarget to use as a source of instructions
static void populateInstInfo(CompoundConstantEmitter &infoArray,
                             CodeGenTarget &target) {
    std::vector<const CodeGenInstruction*> numberedInstructions;
    target.getInstructionsByEnumValue(numberedInstructions);

    unsigned int index;
    unsigned int numInstructions = numberedInstructions.size();

    for (index = 0; index < numInstructions; ++index) {
        const CodeGenInstruction& inst = *numberedInstructions[index];

        CompoundConstantEmitter *infoStruct = new CompoundConstantEmitter;
        infoArray.addEntry(infoStruct);

        FlagsConstantEmitter *instFlags = new FlagsConstantEmitter;
        infoStruct->addEntry(instFlags);

        LiteralConstantEmitter *numOperandsEmitter =
            new LiteralConstantEmitter(inst.OperandList.size());
        infoStruct->addEntry(numOperandsEmitter);

        CompoundConstantEmitter *operandFlagArray = new CompoundConstantEmitter;
        infoStruct->addEntry(operandFlagArray);

        FlagsConstantEmitter *operandFlags[MAX_OPERANDS];

        for (unsigned operandIndex = 0; operandIndex < MAX_OPERANDS; ++operandIndex) {
            operandFlags[operandIndex] = new FlagsConstantEmitter;
            operandFlagArray->addEntry(operandFlags[operandIndex]);
        }

        unsigned numSyntaxes = 0;

        if (target.getName() == "X86") {
            X86PopulateOperands(operandFlags, inst);
            X86ExtractSemantics(*instFlags, operandFlags, inst);
            numSyntaxes = 2;
        }

        CompoundConstantEmitter *operandOrderArray = new CompoundConstantEmitter;
        infoStruct->addEntry(operandOrderArray);

        for (unsigned syntaxIndex = 0; syntaxIndex < MAX_SYNTAXES; ++syntaxIndex) {
            CompoundConstantEmitter *operandOrder = new CompoundConstantEmitter;
            operandOrderArray->addEntry(operandOrder);

            if (syntaxIndex < numSyntaxes) {
                populateOperandOrder(operandOrder, inst, syntaxIndex);
            }
            else {
                for (unsigned operandIndex = 0;
                        operandIndex < MAX_OPERANDS;
                        ++operandIndex) {
                    operandOrder->addEntry(new LiteralConstantEmitter("-1"));
                }
            }
        }
    }
}
Ejemplo n.º 3
0
/// populateInstInfo - Fills an array of InstInfos with information about each
///   instruction in a target
///
/// \param infoArray The array of InstInfo objects to populate
/// \param target    The CodeGenTarget to use as a source of instructions
static void populateInstInfo(CompoundConstantEmitter &infoArray,
                             CodeGenTarget &target) {
  const std::vector<const CodeGenInstruction*> &numberedInstructions =
    target.getInstructionsByEnumValue();

  unsigned int index;
  unsigned int numInstructions = numberedInstructions.size();

  for (index = 0; index < numInstructions; ++index) {
    const CodeGenInstruction& inst = *numberedInstructions[index];

    CompoundConstantEmitter *infoStruct = new CompoundConstantEmitter;
    infoArray.addEntry(infoStruct);

    LiteralConstantEmitter *instType = new LiteralConstantEmitter;
    infoStruct->addEntry(instType);

    LiteralConstantEmitter *numOperandsEmitter =
      new LiteralConstantEmitter(inst.Operands.size());
    infoStruct->addEntry(numOperandsEmitter);

    CompoundConstantEmitter *operandTypeArray = new CompoundConstantEmitter;
    infoStruct->addEntry(operandTypeArray);

    LiteralConstantEmitter *operandTypes[EDIS_MAX_OPERANDS];

    CompoundConstantEmitter *operandFlagArray = new CompoundConstantEmitter;
    infoStruct->addEntry(operandFlagArray);

    FlagsConstantEmitter *operandFlags[EDIS_MAX_OPERANDS];

    for (unsigned operandIndex = 0;
         operandIndex < EDIS_MAX_OPERANDS;
         ++operandIndex) {
      operandTypes[operandIndex] = new LiteralConstantEmitter;
      operandTypeArray->addEntry(operandTypes[operandIndex]);

      operandFlags[operandIndex] = new FlagsConstantEmitter;
      operandFlagArray->addEntry(operandFlags[operandIndex]);
    }

    unsigned numSyntaxes = 0;

    // We don't need to do anything for pseudo-instructions, as we'll never
    // see them here. We'll only see real instructions.
    // We still need to emit null initializers for everything.
    if (!inst.isPseudo) {
      if (target.getName() == "X86") {
        X86PopulateOperands(operandTypes, inst);
        X86ExtractSemantics(*instType, operandFlags, inst);
        numSyntaxes = 2;
      }
      else if (target.getName() == "ARM") {
        ARMPopulateOperands(operandTypes, inst);
        ARMExtractSemantics(*instType, operandTypes, operandFlags, inst);
        numSyntaxes = 1;
      }
    }

    CompoundConstantEmitter *operandOrderArray = new CompoundConstantEmitter;

    infoStruct->addEntry(operandOrderArray);

    for (unsigned syntaxIndex = 0;
         syntaxIndex < EDIS_MAX_SYNTAXES;
         ++syntaxIndex) {
      CompoundConstantEmitter *operandOrder =
        new CompoundConstantEmitter(EDIS_MAX_OPERANDS);

      operandOrderArray->addEntry(operandOrder);

      if (syntaxIndex < numSyntaxes) {
        populateOperandOrder(operandOrder, inst, syntaxIndex);
      }
    }

    infoStruct = NULL;
  }
}
Ejemplo n.º 4
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";
}
Ejemplo n.º 5
0
void AsmWriterEmitter::run(std::ostream &O) {
  EmitSourceFileHeader("Assembly Writer Source Fragment", O);

  CodeGenTarget Target;
  Record *AsmWriter = Target.getAsmWriter();
  std::string ClassName = AsmWriter->getValueAsString("AsmWriterClassName");
  unsigned Variant = AsmWriter->getValueAsInt("Variant");

  O <<
  "/// printInstruction - This method is automatically generated by tablegen\n"
  "/// from the instruction set description.  This method returns true if the\n"
  "/// machine instruction was sufficiently described to print it, otherwise\n"
  "/// it returns false.\n"
    "bool " << Target.getName() << ClassName
            << "::printInstruction(const MachineInstr *MI) {\n";

  std::vector<AsmWriterInst> Instructions;

  for (CodeGenTarget::inst_iterator I = Target.inst_begin(),
         E = Target.inst_end(); I != E; ++I)
    if (!I->second.AsmString.empty())
      Instructions.push_back(AsmWriterInst(I->second, Variant));

  // Get the instruction numbering.
  Target.getInstructionsByEnumValue(NumberedInstructions);
  
  // Compute the CodeGenInstruction -> AsmWriterInst mapping.  Note that not
  // all machine instructions are necessarily being printed, so there may be
  // target instructions not in this map.
  for (unsigned i = 0, e = Instructions.size(); i != e; ++i)
    CGIAWIMap.insert(std::make_pair(Instructions[i].CGI, &Instructions[i]));

  // Build an aggregate string, and build a table of offsets into it.
  std::map<std::string, unsigned> StringOffset;
  std::string AggregateString;
  AggregateString.push_back(0);  // "\0"
  AggregateString.push_back(0);  // "\0"
  
  /// OpcodeInfo - This encodes the index of the string to use for the first
  /// chunk of the output as well as indices used for operand printing.
  std::vector<unsigned> OpcodeInfo;
  
  unsigned MaxStringIdx = 0;
  for (unsigned i = 0, e = NumberedInstructions.size(); i != e; ++i) {
    AsmWriterInst *AWI = CGIAWIMap[NumberedInstructions[i]];
    unsigned Idx;
    if (AWI == 0) {
      // Something not handled by the asmwriter printer.
      Idx = 0;
    } else if (AWI->Operands[0].OperandType != 
                        AsmWriterOperand::isLiteralTextOperand ||
               AWI->Operands[0].Str.empty()) {
      // Something handled by the asmwriter printer, but with no leading string.
      Idx = 1;
    } else {
      unsigned &Entry = StringOffset[AWI->Operands[0].Str];
      if (Entry == 0) {
        // Add the string to the aggregate if this is the first time found.
        MaxStringIdx = Entry = AggregateString.size();
        std::string Str = AWI->Operands[0].Str;
        UnescapeString(Str);
        AggregateString += Str;
        AggregateString += '\0';
      }
      Idx = Entry;

      // Nuke the string from the operand list.  It is now handled!
      AWI->Operands.erase(AWI->Operands.begin());
    }
    OpcodeInfo.push_back(Idx);
  }
  
  // Figure out how many bits we used for the string index.
  unsigned AsmStrBits = Log2_32_Ceil(MaxStringIdx+1);
  
  // To reduce code size, we compactify common instructions into a few bits
  // in the opcode-indexed table.
  unsigned BitsLeft = 32-AsmStrBits;

  std::vector<std::vector<std::string> > TableDrivenOperandPrinters;
  
  bool isFirst = true;
  while (1) {
    std::vector<std::string> UniqueOperandCommands;

    // For the first operand check, add a default value for instructions with
    // just opcode strings to use.
    if (isFirst) {
      UniqueOperandCommands.push_back("    return true;\n");
      isFirst = false;
    }
    
    std::vector<unsigned> InstIdxs;
    std::vector<unsigned> NumInstOpsHandled;
    FindUniqueOperandCommands(UniqueOperandCommands, InstIdxs,
                              NumInstOpsHandled);
    
    // If we ran out of operands to print, we're done.
    if (UniqueOperandCommands.empty()) break;
    
    // Compute the number of bits we need to represent these cases, this is
    // ceil(log2(numentries)).
    unsigned NumBits = Log2_32_Ceil(UniqueOperandCommands.size());
    
    // If we don't have enough bits for this operand, don't include it.
    if (NumBits > BitsLeft) {
      DOUT << "Not enough bits to densely encode " << NumBits
           << " more bits\n";
      break;
    }
    
    // Otherwise, we can include this in the initial lookup table.  Add it in.
    BitsLeft -= NumBits;
    for (unsigned i = 0, e = InstIdxs.size(); i != e; ++i)
      if (InstIdxs[i] != ~0U)
        OpcodeInfo[i] |= InstIdxs[i] << (BitsLeft+AsmStrBits);
    
    // Remove the info about this operand.
    for (unsigned i = 0, e = NumberedInstructions.size(); i != e; ++i) {
      if (AsmWriterInst *Inst = getAsmWriterInstByID(i))
        if (!Inst->Operands.empty()) {
          unsigned NumOps = NumInstOpsHandled[InstIdxs[i]];
          assert(NumOps <= Inst->Operands.size() &&
                 "Can't remove this many ops!");
          Inst->Operands.erase(Inst->Operands.begin(),
                               Inst->Operands.begin()+NumOps);
        }
    }
    
    // Remember the handlers for this set of operands.
    TableDrivenOperandPrinters.push_back(UniqueOperandCommands);
  }
  
  
  
  O<<"  static const unsigned OpInfo[] = {\n";
  for (unsigned i = 0, e = NumberedInstructions.size(); i != e; ++i) {
    O << "    " << OpcodeInfo[i] << "U,\t// "
      << NumberedInstructions[i]->TheDef->getName() << "\n";
  }
  // Add a dummy entry so the array init doesn't end with a comma.
  O << "    0U\n";
  O << "  };\n\n";
  
  // Emit the string itself.
  O << "  const char *AsmStrs = \n    \"";
  unsigned CharsPrinted = 0;
  EscapeString(AggregateString);
  for (unsigned i = 0, e = AggregateString.size(); i != e; ++i) {
    if (CharsPrinted > 70) {
      O << "\"\n    \"";
      CharsPrinted = 0;
    }
    O << AggregateString[i];
    ++CharsPrinted;
    
    // Print escape sequences all together.
    if (AggregateString[i] == '\\') {
      assert(i+1 < AggregateString.size() && "Incomplete escape sequence!");
      if (isdigit(AggregateString[i+1])) {
        assert(isdigit(AggregateString[i+2]) && isdigit(AggregateString[i+3]) &&
               "Expected 3 digit octal escape!");
        O << AggregateString[++i];
        O << AggregateString[++i];
        O << AggregateString[++i];
        CharsPrinted += 3;
      } else {
        O << AggregateString[++i];
        ++CharsPrinted;
      }
    }
  }
  O << "\";\n\n";

  O << "  if (MI->getOpcode() == TargetInstrInfo::INLINEASM) {\n"
    << "    O << \"\\t\";\n"
    << "    printInlineAsm(MI);\n"
    << "    return true;\n"
    << "  } else if (MI->getOpcode() == TargetInstrInfo::LABEL) {\n"
    << "    printLabel(MI);\n"
    << "    return true;\n"
    << "  } else if (MI->getOpcode() == TargetInstrInfo::DECLARE) {\n"
    << "    printDeclare(MI);\n"
    << "    return true;\n"
    << "  } else if (MI->getOpcode() == TargetInstrInfo::IMPLICIT_DEF) {\n"
    << "    printImplicitDef(MI);\n"
    << "    return true;\n"
    << "  }\n\n";
  
  O << "  O << \"\\t\";\n\n";

  O << "  // Emit the opcode for the instruction.\n"
    << "  unsigned Bits = OpInfo[MI->getOpcode()];\n"
    << "  if (Bits == 0) return false;\n"
    << "  O << AsmStrs+(Bits & " << (1 << AsmStrBits)-1 << ");\n\n";

  // Output the table driven operand information.
  BitsLeft = 32-AsmStrBits;
  for (unsigned i = 0, e = TableDrivenOperandPrinters.size(); i != e; ++i) {
    std::vector<std::string> &Commands = TableDrivenOperandPrinters[i];

    // Compute the number of bits we need to represent these cases, this is
    // ceil(log2(numentries)).
    unsigned NumBits = Log2_32_Ceil(Commands.size());
    assert(NumBits <= BitsLeft && "consistency error");
    
    // Emit code to extract this field from Bits.
    BitsLeft -= NumBits;
    
    O << "\n  // Fragment " << i << " encoded into " << NumBits
      << " bits for " << Commands.size() << " unique commands.\n";
    
    if (Commands.size() == 2) {
      // Emit two possibilitys with if/else.
      O << "  if ((Bits >> " << (BitsLeft+AsmStrBits) << ") & "
        << ((1 << NumBits)-1) << ") {\n"
        << Commands[1]
        << "  } else {\n"
        << Commands[0]
        << "  }\n\n";
    } else {
      O << "  switch ((Bits >> " << (BitsLeft+AsmStrBits) << ") & "
        << ((1 << NumBits)-1) << ") {\n"
        << "  default:   // unreachable.\n";
      
      // Print out all the cases.
      for (unsigned i = 0, e = Commands.size(); i != e; ++i) {
        O << "  case " << i << ":\n";
        O << Commands[i];
        O << "    break;\n";
      }
      O << "  }\n\n";
    }
  }
  
  // Okay, delete instructions with no operand info left.
  for (unsigned i = 0, e = Instructions.size(); i != e; ++i) {
    // Entire instruction has been emitted?
    AsmWriterInst &Inst = Instructions[i];
    if (Inst.Operands.empty()) {
      Instructions.erase(Instructions.begin()+i);
      --i; --e;
    }
  }

    
  // Because this is a vector, we want to emit from the end.  Reverse all of the
  // elements in the vector.
  std::reverse(Instructions.begin(), Instructions.end());
  
  if (!Instructions.empty()) {
    // Find the opcode # of inline asm.
    O << "  switch (MI->getOpcode()) {\n";
    while (!Instructions.empty())
      EmitInstructions(Instructions, O);

    O << "  }\n";
    O << "  return true;\n";
  }
  
  O << "}\n";
}