Viewing file:  MCELFStreamer.h (5.87 KB) -rw-r--r--
Select action/file-type:
 (+) |  (+) |  (+) | Code (+) | Session (+) |  (+) | SDB (+) |  (+) |  (+) |  (+) |  (+) |  (+) |
//===- MCELFStreamer.h - MCStreamer ELF Object File Interface ---*- C++ -*-===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_MC_MCELFSTREAMER_H
#define LLVM_MC_MCELFSTREAMER_H
#include "llvm/ADT/SmallVector.h"
#include "llvm/MC/MCDirectives.h"
#include "llvm/MC/MCELFObjectWriter.h"
#include "llvm/MC/MCObjectStreamer.h"
namespace llvm {
class MCContext;
class MCDataFragment;
class MCFragment;
class MCObjectWriter;
class MCSection;
class MCSubtargetInfo;
class MCSymbol;
class MCSymbolRefExpr;
class MCAsmBackend;
class MCCodeEmitter;
class MCExpr;
class MCInst;
class MCELFStreamer : public MCObjectStreamer {
public:
MCELFStreamer(MCContext &Context, std::unique_ptr<MCAsmBackend> TAB,
std::unique_ptr<MCObjectWriter> OW,
std::unique_ptr<MCCodeEmitter> Emitter);
~MCELFStreamer() override = default;
/// state management
void reset() override {
SeenIdent = false;
MCObjectStreamer::reset();
}
ELFObjectWriter &getWriter();
/// \name MCStreamer Interface
/// @{
void initSections(bool NoExecStack, const MCSubtargetInfo &STI) override;
void changeSection(MCSection *Section, uint32_t Subsection = 0) override;
void emitLabel(MCSymbol *Symbol, SMLoc Loc = SMLoc()) override;
void emitLabelAtPos(MCSymbol *Symbol, SMLoc Loc, MCDataFragment &F,
uint64_t Offset) override;
void emitAssemblerFlag(MCAssemblerFlag Flag) override;
void emitThumbFunc(MCSymbol *Func) override;
void emitWeakReference(MCSymbol *Alias, const MCSymbol *Symbol) override;
bool emitSymbolAttribute(MCSymbol *Symbol, MCSymbolAttr Attribute) override;
void emitSymbolDesc(MCSymbol *Symbol, unsigned DescValue) override;
void emitCommonSymbol(MCSymbol *Symbol, uint64_t Size,
Align ByteAlignment) override;
void emitELFSize(MCSymbol *Symbol, const MCExpr *Value) override;
void emitELFSymverDirective(const MCSymbol *OriginalSym, StringRef Name,
bool KeepOriginalSym) override;
void emitLocalCommonSymbol(MCSymbol *Symbol, uint64_t Size,
Align ByteAlignment) override;
void emitZerofill(MCSection *Section, MCSymbol *Symbol = nullptr,
uint64_t Size = 0, Align ByteAlignment = Align(1),
SMLoc L = SMLoc()) override;
void emitTBSSSymbol(MCSection *Section, MCSymbol *Symbol, uint64_t Size,
Align ByteAlignment = Align(1)) override;
void emitValueImpl(const MCExpr *Value, unsigned Size,
SMLoc Loc = SMLoc()) override;
void emitIdent(StringRef IdentString) override;
void emitValueToAlignment(Align, int64_t, unsigned, unsigned) override;
void emitCGProfileEntry(const MCSymbolRefExpr *From,
const MCSymbolRefExpr *To, uint64_t Count) override;
// This is final. Override MCTargetStreamer::finish instead for
// target-specific code.
void finishImpl() final;
void emitBundleAlignMode(Align Alignment) override;
void emitBundleLock(bool AlignToEnd) override;
void emitBundleUnlock() override;
/// ELF object attributes section emission support
struct AttributeItem {
// This structure holds all attributes, accounting for their string /
// numeric value, so we can later emit them in declaration order, keeping
// all in the same vector.
enum {
HiddenAttribute = 0,
NumericAttribute,
TextAttribute,
NumericAndTextAttributes
} Type;
unsigned Tag;
unsigned IntValue;
std::string StringValue;
};
// Attributes that are added and managed entirely by target.
SmallVector<AttributeItem, 64> Contents;
void setAttributeItem(unsigned Attribute, unsigned Value,
bool OverwriteExisting);
void setAttributeItem(unsigned Attribute, StringRef Value,
bool OverwriteExisting);
void setAttributeItems(unsigned Attribute, unsigned IntValue,
StringRef StringValue, bool OverwriteExisting);
void emitAttributesSection(StringRef Vendor, const Twine &Section,
unsigned Type, MCSection *&AttributeSection) {
createAttributesSection(Vendor, Section, Type, AttributeSection, Contents);
}
private:
AttributeItem *getAttributeItem(unsigned Attribute);
size_t calculateContentSize(SmallVector<AttributeItem, 64> &AttrsVec);
void createAttributesSection(StringRef Vendor, const Twine &Section,
unsigned Type, MCSection *&AttributeSection,
SmallVector<AttributeItem, 64> &AttrsVec);
// GNU attributes that will get emitted at the end of the asm file.
SmallVector<AttributeItem, 64> GNUAttributes;
public:
void emitGNUAttribute(unsigned Tag, unsigned Value) override {
AttributeItem Item = {AttributeItem::NumericAttribute, Tag, Value,
std::string(StringRef(""))};
GNUAttributes.push_back(Item);
}
private:
bool isBundleLocked() const;
void emitInstToFragment(const MCInst &Inst, const MCSubtargetInfo &) override;
void emitInstToData(const MCInst &Inst, const MCSubtargetInfo &) override;
void fixSymbolsInTLSFixups(const MCExpr *expr);
void finalizeCGProfileEntry(const MCSymbolRefExpr *&S, uint64_t Offset);
void finalizeCGProfile();
bool SeenIdent = false;
};
MCELFStreamer *createARMELFStreamer(MCContext &Context,
std::unique_ptr<MCAsmBackend> TAB,
std::unique_ptr<MCObjectWriter> OW,
std::unique_ptr<MCCodeEmitter> Emitter,
bool IsThumb, bool IsAndroid);
} // end namespace llvm
#endif // LLVM_MC_MCELFSTREAMER_H
|