llvm-6502/include/llvm/MC/MCStreamer.h
Kevin Enderby 5026ae4514 Removed the DumpSymbolsandMacros and LoadSymbolsandMacros MCStreamer API as
the parsing of the .dump and .load should be done in the assembly parser and
not have any need for an MCStreamer API.  Changed the code for now so these
just produce an error saying these specific directives are not yet implemented
since they are likely no longer used and may never need to be implemented.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@76462 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-20 20:25:37 +00:00

251 lines
10 KiB
C++

//===- MCStreamer.h - High-level Streaming Machine Code Output --*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file declares the MCStreamer class.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_MC_MCSTREAMER_H
#define LLVM_MC_MCSTREAMER_H
#include "llvm/Support/DataTypes.h"
namespace llvm {
class MCContext;
class MCValue;
class MCInst;
class MCSection;
class MCSymbol;
class raw_ostream;
/// MCStreamer - Streaming machine code generation interface. This interface
/// is intended to provide a programatic interface that is very similar to the
/// level that an assembler .s file provides. It has callbacks to emit bytes,
/// "emit directives", etc. The implementation of this interface retains
/// state to know what the current section is etc.
///
/// There are multiple implementations of this interface: one for writing out
/// a .s file, and implementations that write out .o files of various formats.
///
class MCStreamer {
public:
enum SymbolAttr {
Global, /// .globl
Hidden, /// .hidden (ELF)
IndirectSymbol, /// .indirect_symbol (Apple)
Internal, /// .internal (ELF)
LazyReference, /// .lazy_reference (Apple)
NoDeadStrip, /// .no_dead_strip (Apple)
PrivateExtern, /// .private_extern (Apple)
Protected, /// .protected (ELF)
Reference, /// .reference (Apple)
Weak, /// .weak
WeakDefinition, /// .weak_definition (Apple)
WeakReference, /// .weak_reference (Apple)
SymbolAttrFirst = Global,
SymbolAttrLast = WeakReference
};
enum AssemblerFlag {
SubsectionsViaSymbols /// .subsections_via_symbols (Apple)
};
private:
MCContext &Context;
MCStreamer(const MCStreamer&); // DO NOT IMPLEMENT
MCStreamer &operator=(const MCStreamer&); // DO NOT IMPLEMENT
protected:
MCStreamer(MCContext &Ctx);
public:
virtual ~MCStreamer();
MCContext &getContext() const { return Context; }
/// @name Symbol & Section Management
/// @{
/// SwitchSection - Set the current section where code is being emitted to
/// @param Section.
///
/// This corresponds to assembler directives like .section, .text, etc.
virtual void SwitchSection(MCSection *Section) = 0;
/// EmitLabel - Emit a label for @param Symbol into the current section.
///
/// This corresponds to an assembler statement such as:
/// foo:
///
/// @param Symbol - The symbol to emit. A given symbol should only be
/// emitted as a label once, and symbols emitted as a label should never be
/// used in an assignment.
//
// FIXME: What to do about the current section? Should we get rid of the
// symbol section in the constructor and initialize it here?
virtual void EmitLabel(MCSymbol *Symbol) = 0;
/// EmitAssemblerFlag - Note in the output the specified @param Flag
virtual void EmitAssemblerFlag(AssemblerFlag Flag) = 0;
/// EmitAssignment - Emit an assignment of @param Value to @param Symbol.
///
/// This corresponds to an assembler statement such as:
/// symbol = value
///
/// The assignment generates no code, but has the side effect of binding the
/// value in the current context. For the assembly streamer, this prints the
/// binding into the .s file.
///
/// @param Symbol - The symbol being assigned to.
/// @param Value - The value for the symbol.
/// @param MakeAbsolute - If true, then the symbol should be given the
/// absolute value of @param Value, even if @param Value would be
/// relocatable expression. This corresponds to the ".set" directive.
virtual void EmitAssignment(MCSymbol *Symbol, const MCValue &Value,
bool MakeAbsolute = false) = 0;
/// EmitSymbolAttribute - Add the given @param Attribute to @param Symbol.
//
// FIXME: This doesn't make much sense, could we just have attributes be on
// the symbol and make the printer smart enough to add the right symbols?
// This should work as long as the order of attributes in the file doesn't
// matter.
virtual void EmitSymbolAttribute(MCSymbol *Symbol,
SymbolAttr Attribute) = 0;
/// EmitSymbolDesc - Set the @param DescValue for the @param Symbol.
///
/// @param Symbol - The symbol to have its n_desc field set.
/// @param DescValue - The value to set into the n_desc field.
virtual void EmitSymbolDesc(MCSymbol *Symbol, unsigned DescValue) = 0;
/// EmitLocalSymbol - Emit a local symbol of @param Value to @param Symbol.
///
/// @param Symbol - The local symbol being created.
/// @param Value - The value for the symbol.
virtual void EmitLocalSymbol(MCSymbol *Symbol, const MCValue &Value) = 0;
/// EmitCommonSymbol - Emit a common or local common symbol of @param Size
/// with the @param Pow2Alignment if non-zero.
///
/// @param Symbol - The common symbol to emit.
/// @param Size - The size of the common symbol.
/// @param Pow2Alignment - The alignment of the common symbol if non-zero.
/// @param IsLocal - If true, then the symbol is to be a local common
virtual void EmitCommonSymbol(MCSymbol *Symbol, unsigned Size,
unsigned Pow2Alignment, bool IsLocal) = 0;
/// EmitZerofill - Emit a the zerofill section and possiblity a symbol, if
/// @param Symbol is non-NULL, for @param Size and with the @param
/// Pow2Alignment if non-zero.
///
/// @param Section - The zerofill section to create and or to put the symbol
/// @param Symbol - The zerofill symbol to emit, if non-NULL.
/// @param Size - The size of the zerofill symbol.
/// @param Pow2Alignment - The alignment of the zerofill symbol if non-zero.
virtual void EmitZerofill(MCSection *Section, MCSymbol *Symbol = 0,
unsigned Size = 0,unsigned Pow2Alignment = 0) = 0;
/// AbortAssembly - Stop and don't produce output, printing @param
/// AbortReason if non-NULL to indicate the reason the assembly is
/// terminated.
///
/// @param AbortReason - The reason assembly is terminated, if non-NULL.
virtual void AbortAssembly(const char *AbortReason) = 0;
/// @}
/// @name Generating Data
/// @{
/// EmitBytes - Emit @param Length bytes starting at @param Data into the
/// output.
///
/// This is used to implement assembler directives such as .byte, .ascii,
/// etc.
virtual void EmitBytes(const char *Data, unsigned Length) = 0;
/// EmitValue - Emit the expression @param Value into the output as a native
/// integer of the given @param Size bytes.
///
/// This is used to implement assembler directives such as .word, .quad,
/// etc.
///
/// @param Value - The value to emit.
/// @param Size - The size of the integer (in bytes) to emit. This must
/// match a native machine width.
virtual void EmitValue(const MCValue &Value, unsigned Size) = 0;
/// EmitValueToAlignment - Emit some number of copies of @param Value until
/// the byte alignment @param ByteAlignment is reached.
///
/// If the number of bytes need to emit for the alignment is not a multiple
/// of @param ValueSize, then the contents of the emitted fill bytes is
/// undefined.
///
/// This used to implement the .align assembler directive.
///
/// @param ByteAlignment - The alignment to reach. This must be a power of
/// two on some targets.
/// @param Value - The value to use when filling bytes.
/// @param Size - The size of the integer (in bytes) to emit for @param
/// Value. This must match a native machine width.
/// @param MaxBytesToEmit - The maximum numbers of bytes to emit, or 0. If
/// the alignment cannot be reached in this many bytes, no bytes are
/// emitted.
virtual void EmitValueToAlignment(unsigned ByteAlignment, int64_t Value = 0,
unsigned ValueSize = 1,
unsigned MaxBytesToEmit = 0) = 0;
/// EmitValueToOffset - Emit some number of copies of @param Value until the
/// byte offset @param Offset is reached.
///
/// This is used to implement assembler directives such as .org.
///
/// @param Offset - The offset to reach.This may be an expression, but the
/// expression must be associated with the current section.
/// @param Value - The value to use when filling bytes.
//
// FIXME: How are we going to signal failures out of this?
virtual void EmitValueToOffset(const MCValue &Offset,
unsigned char Value = 0) = 0;
/// @}
/// EmitInstruction - Emit the given @param Instruction into the current
/// section.
virtual void EmitInstruction(const MCInst &Inst) = 0;
/// Finish - Finish emission of machine code and flush any output.
virtual void Finish() = 0;
};
/// createAsmStreamer - Create a machine code streamer which will print out
/// assembly for the native target, suitable for compiling with a native
/// assembler.
MCStreamer *createAsmStreamer(MCContext &Ctx, raw_ostream &OS);
// FIXME: These two may end up getting rolled into a single
// createObjectStreamer interface, which implements the assembler backend, and
// is parameterized on an output object file writer.
/// createMachOStream - Create a machine code streamer which will generative
/// Mach-O format object files.
MCStreamer *createMachOStreamer(MCContext &Ctx, raw_ostream &OS);
/// createELFStreamer - Create a machine code streamer which will generative
/// ELF format object files.
MCStreamer *createELFStreamer(MCContext &Ctx, raw_ostream &OS);
} // end namespace llvm
#endif