mirror of
https://github.com/c64scene-ar/llvm-6502.git
synced 2024-08-21 18:29:46 +00:00
Differential Revision: http://reviews.llvm.org/D8217 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@238659 91177308-0d34-0410-b5e6-96231b3b80d8
144 lines
5.1 KiB
C++
144 lines
5.1 KiB
C++
//===-- llvm/MC/MCAsmBackend.h - MC Asm Backend -----------------*- C++ -*-===//
|
|
//
|
|
// The LLVM Compiler Infrastructure
|
|
//
|
|
// This file is distributed under the University of Illinois Open Source
|
|
// License. See LICENSE.TXT for details.
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
#ifndef LLVM_MC_MCASMBACKEND_H
|
|
#define LLVM_MC_MCASMBACKEND_H
|
|
|
|
#include "llvm/ADT/ArrayRef.h"
|
|
#include "llvm/MC/MCDirectives.h"
|
|
#include "llvm/MC/MCDwarf.h"
|
|
#include "llvm/MC/MCFixup.h"
|
|
#include "llvm/Support/DataTypes.h"
|
|
#include "llvm/Support/ErrorHandling.h"
|
|
|
|
namespace llvm {
|
|
class MCAsmLayout;
|
|
class MCAssembler;
|
|
class MCELFObjectTargetWriter;
|
|
struct MCFixupKindInfo;
|
|
class MCFragment;
|
|
class MCInst;
|
|
class MCRelaxableFragment;
|
|
class MCObjectWriter;
|
|
class MCSection;
|
|
class MCValue;
|
|
class raw_ostream;
|
|
|
|
/// Generic interface to target specific assembler backends.
|
|
class MCAsmBackend {
|
|
MCAsmBackend(const MCAsmBackend &) = delete;
|
|
void operator=(const MCAsmBackend &) = delete;
|
|
|
|
protected: // Can only create subclasses.
|
|
MCAsmBackend();
|
|
|
|
unsigned HasDataInCodeSupport : 1;
|
|
|
|
public:
|
|
virtual ~MCAsmBackend();
|
|
|
|
/// lifetime management
|
|
virtual void reset() {}
|
|
|
|
/// Create a new MCObjectWriter instance for use by the assembler backend to
|
|
/// emit the final object file.
|
|
virtual MCObjectWriter *createObjectWriter(raw_pwrite_stream &OS) const = 0;
|
|
|
|
/// Create a new ELFObjectTargetWriter to enable non-standard
|
|
/// ELFObjectWriters.
|
|
virtual MCELFObjectTargetWriter *createELFObjectTargetWriter() const {
|
|
llvm_unreachable("createELFObjectTargetWriter is not supported by asm "
|
|
"backend");
|
|
}
|
|
|
|
/// Check whether this target implements data-in-code markers. If not, data
|
|
/// region directives will be ignored.
|
|
bool hasDataInCodeSupport() const { return HasDataInCodeSupport; }
|
|
|
|
/// \name Target Fixup Interfaces
|
|
/// @{
|
|
|
|
/// Get the number of target specific fixup kinds.
|
|
virtual unsigned getNumFixupKinds() const = 0;
|
|
|
|
/// Get information on a fixup kind.
|
|
virtual const MCFixupKindInfo &getFixupKindInfo(MCFixupKind Kind) const;
|
|
|
|
/// Target hook to adjust the literal value of a fixup if necessary.
|
|
/// IsResolved signals whether the caller believes a relocation is needed; the
|
|
/// target can modify the value. The default does nothing.
|
|
virtual void processFixupValue(const MCAssembler &Asm,
|
|
const MCAsmLayout &Layout,
|
|
const MCFixup &Fixup, const MCFragment *DF,
|
|
const MCValue &Target, uint64_t &Value,
|
|
bool &IsResolved) {}
|
|
|
|
/// Apply the \p Value for given \p Fixup into the provided data fragment, at
|
|
/// the offset specified by the fixup and following the fixup kind as
|
|
/// appropriate.
|
|
virtual void applyFixup(const MCFixup &Fixup, char *Data, unsigned DataSize,
|
|
uint64_t Value, bool IsPCRel) const = 0;
|
|
|
|
/// @}
|
|
|
|
/// \name Target Relaxation Interfaces
|
|
/// @{
|
|
|
|
/// Check whether the given instruction may need relaxation.
|
|
///
|
|
/// \param Inst - The instruction to test.
|
|
virtual bool mayNeedRelaxation(const MCInst &Inst) const = 0;
|
|
|
|
/// Target specific predicate for whether a given fixup requires the
|
|
/// associated instruction to be relaxed.
|
|
virtual bool fixupNeedsRelaxationAdvanced(const MCFixup &Fixup, bool Resolved,
|
|
uint64_t Value,
|
|
const MCRelaxableFragment *DF,
|
|
const MCAsmLayout &Layout) const;
|
|
|
|
/// Simple predicate for targets where !Resolved implies requiring relaxation
|
|
virtual bool fixupNeedsRelaxation(const MCFixup &Fixup, uint64_t Value,
|
|
const MCRelaxableFragment *DF,
|
|
const MCAsmLayout &Layout) const = 0;
|
|
|
|
/// Relax the instruction in the given fragment to the next wider instruction.
|
|
///
|
|
/// \param Inst The instruction to relax, which may be the same as the
|
|
/// output.
|
|
/// \param [out] Res On return, the relaxed instruction.
|
|
virtual void relaxInstruction(const MCInst &Inst, MCInst &Res) const = 0;
|
|
|
|
/// @}
|
|
|
|
/// Returns the minimum size of a nop in bytes on this target. The assembler
|
|
/// will use this to emit excess padding in situations where the padding
|
|
/// required for simple alignment would be less than the minimum nop size.
|
|
///
|
|
virtual unsigned getMinimumNopSize() const { return 1; }
|
|
|
|
/// Write an (optimal) nop sequence of Count bytes to the given output. If the
|
|
/// target cannot generate such a sequence, it should return an error.
|
|
///
|
|
/// \return - True on success.
|
|
virtual bool writeNopData(uint64_t Count, MCObjectWriter *OW) const = 0;
|
|
|
|
/// Handle any target-specific assembler flags. By default, do nothing.
|
|
virtual void handleAssemblerFlag(MCAssemblerFlag Flag) {}
|
|
|
|
/// \brief Generate the compact unwind encoding for the CFI instructions.
|
|
virtual uint32_t
|
|
generateCompactUnwindEncoding(ArrayRef<MCCFIInstruction>) const {
|
|
return 0;
|
|
}
|
|
};
|
|
|
|
} // End llvm namespace
|
|
|
|
#endif
|