llvm-6502/include/llvm/CodeGen/MachineCodeEmitter.h
2005-07-28 18:13:59 +00:00

116 lines
4.1 KiB
C++

//===-- llvm/CodeGen/MachineCodeEmitter.h - Code emission -------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file was developed by the LLVM research group and is distributed under
// the University of Illinois Open Source License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file defines an abstract interface that is used by the machine code
// emission framework to output the code. This allows machine code emission to
// be separated from concerns such as resolution of call targets, and where the
// machine code will be written (memory or disk, f.e.).
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_CODEGEN_MACHINECODEEMITTER_H
#define LLVM_CODEGEN_MACHINECODEEMITTER_H
#include "llvm/Support/DataTypes.h"
namespace llvm {
class MachineBasicBlock;
class MachineConstantPool;
class MachineFunction;
class MachineRelocation;
class Value;
class GlobalValue;
class Function;
class MachineCodeEmitter {
public:
virtual ~MachineCodeEmitter() {}
/// startFunction - This callback is invoked when the specified function is
/// about to be code generated.
///
virtual void startFunction(MachineFunction &F) {}
/// finishFunction - This callback is invoked when the specified function has
/// finished code generation.
///
virtual void finishFunction(MachineFunction &F) {}
/// emitConstantPool - This callback is invoked to output the constant pool
/// for the function.
virtual void emitConstantPool(MachineConstantPool *MCP) {}
/// startFunctionStub - This callback is invoked when the JIT needs the
/// address of a function that has not been code generated yet. The StubSize
/// specifies the total size required by the stub. Stubs are not allowed to
/// have constant pools, the can only use the other emit* methods.
///
virtual void startFunctionStub(unsigned StubSize) {}
/// finishFunctionStub - This callback is invoked to terminate a function
/// stub.
///
virtual void *finishFunctionStub(const Function *F) { return 0; }
/// emitByte - This callback is invoked when a byte needs to be written to the
/// output stream.
///
virtual void emitByte(unsigned char B) {}
/// emitWordAt - This callback is invoked when a word needs to be written to
/// the output stream at a different position than the current PC (for
/// instance, when performing relocations).
///
virtual void emitWordAt(unsigned W, unsigned *Ptr) {}
/// emitWord - This callback is invoked when a word needs to be written to the
/// output stream.
///
virtual void emitWord(unsigned W) = 0;
/// getCurrentPCValue - This returns the address that the next emitted byte
/// will be output to.
///
virtual uint64_t getCurrentPCValue() = 0;
/// getCurrentPCOffset - Return the offset from the start of the emitted
/// buffer that we are currently writing to.
virtual uint64_t getCurrentPCOffset() = 0;
/// addRelocation - Whenever a relocatable address is needed, it should be
/// noted with this interface.
virtual void addRelocation(const MachineRelocation &MR) = 0;
// getConstantPoolEntryAddress - Return the address of the 'Index' entry in
// the constant pool that was last emitted with the 'emitConstantPool' method.
//
virtual uint64_t getConstantPoolEntryAddress(unsigned Index) = 0;
// allocateGlobal - Allocate some space for a global variable.
virtual unsigned char* allocateGlobal(unsigned size, unsigned alignment) = 0;
/// createDebugEmitter - Return a dynamically allocated machine
/// code emitter, which just prints the opcodes and fields out the cout. This
/// can be used for debugging users of the MachineCodeEmitter interface.
///
static MachineCodeEmitter *createDebugEmitter();
/// createFilePrinterEmitter - Return a dynamically allocated
/// machine code emitter, which prints binary code to a file. This
/// can be used for debugging users of the MachineCodeEmitter interface.
///
static MachineCodeEmitter *createFilePrinterEmitter(MachineCodeEmitter&);
};
} // End llvm namespace
#endif