llvm-6502/utils/TableGen/FixedLenDecoderEmitter.h

81 lines
2.4 KiB
C++

//===------------ FixedLenDecoderEmitter.h - Decoder Generator --*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// It contains the tablegen backend that emits the decoder functions for
// targets with fixed length instruction set.
//
//===----------------------------------------------------------------------===//
#ifndef FixedLenDECODEREMITTER_H
#define FixedLenDECODEREMITTER_H
#include "CodeGenTarget.h"
#include "TableGenBackend.h"
#include "llvm/Support/DataTypes.h"
namespace llvm {
struct EncodingField {
unsigned Base, Width, Offset;
EncodingField(unsigned B, unsigned W, unsigned O)
: Base(B), Width(W), Offset(O) { }
};
struct OperandInfo {
std::vector<EncodingField> Fields;
std::string Decoder;
OperandInfo(std::string D)
: Decoder(D) { }
void addField(unsigned Base, unsigned Width, unsigned Offset) {
Fields.push_back(EncodingField(Base, Width, Offset));
}
unsigned numFields() { return Fields.size(); }
typedef std::vector<EncodingField>::iterator iterator;
iterator begin() { return Fields.begin(); }
iterator end() { return Fields.end(); }
};
class FixedLenDecoderEmitter : public TableGenBackend {
public:
FixedLenDecoderEmitter(RecordKeeper &R,
std::string GPrefix = "if (",
std::string GPostfix = " == MCDisassembler::Fail) return MCDisassembler::Fail;",
std::string ROK = "MCDisassembler::Success",
std::string RFail = "MCDisassembler::Fail",
std::string L = "") :
Records(R), Target(R),
NumberedInstructions(Target.getInstructionsByEnumValue()),
GuardPrefix(GPrefix), GuardPostfix(GPostfix),
ReturnOK(ROK), ReturnFail(RFail), Locals(L) {}
// run - Output the code emitter
void run(raw_ostream &o);
private:
RecordKeeper &Records;
CodeGenTarget Target;
std::vector<const CodeGenInstruction*> NumberedInstructions;
std::vector<unsigned> Opcodes;
std::map<unsigned, std::vector<OperandInfo> > Operands;
public:
std::string GuardPrefix, GuardPostfix;
std::string ReturnOK, ReturnFail;
std::string Locals;
};
} // end llvm namespace
#endif