class MCObjectStreamer

Declaration

class MCObjectStreamer : public MCStreamer { /* full declaration omitted */ };

Description

Streaming object file generation interface. This class provides an implementation of the MCStreamer interface which is suitable for use with the assembler backend. Specific object file formats are expected to subclass this interface to implement directives specific to that file format or custom semantics expected by the object writer implementation.

Declared at: llvm/include/llvm/MC/MCObjectStreamer.h:35

Inherits from: MCStreamer

Method Overview

Inherited from MCStreamer:

Methods

void ChangeSection(llvm::MCSection* Section,
                   const llvm::MCExpr* Subsection)

Description

Update streamer for a new active section. This is called by PopSection and SwitchSection, if the current section changes.

Declared at: llvm/include/llvm/MC/MCObjectStreamer.h:125

Parameters

llvm::MCSection* Section
const llvm::MCExpr* Subsection

void EmitAddrsig()

Declared at: llvm/include/llvm/MC/MCObjectStreamer.h:184

void EmitAddrsigSym(const llvm::MCSymbol* Sym)

Declared at: llvm/include/llvm/MC/MCObjectStreamer.h:185

Parameters

const llvm::MCSymbol* Sym

void EmitAssignment(llvm::MCSymbol* Symbol,
                    const llvm::MCExpr* Value)

Description

Emit an assignment of \p Value to \p 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.

Declared at: llvm/include/llvm/MC/MCObjectStreamer.h:119

Parameters

llvm::MCSymbol* Symbol
- The symbol being assigned to.
const llvm::MCExpr* Value
- The value for the symbol.

void EmitBundleAlignMode(unsigned int AlignPow2)

Description

Set the bundle alignment mode from now on in the section. The argument is the power of 2 to which the alignment is set. The value 0 means turn the bundle alignment off.

Declared at: llvm/include/llvm/MC/MCObjectStreamer.h:132

Parameters

unsigned int AlignPow2

void EmitBundleLock(bool AlignToEnd)

Description

The following instructions are a bundle-locked group.

Declared at: llvm/include/llvm/MC/MCObjectStreamer.h:133

Parameters

bool AlignToEnd
- If true, the bundle-locked group will be aligned to the end of a bundle.

void EmitBundleUnlock()

Description

Ends a bundle-locked group.

Declared at: llvm/include/llvm/MC/MCObjectStreamer.h:134

void EmitBytes(llvm::StringRef Data)

Description

Emit the bytes in \p Data into the output. This is used to implement assembler directives such as .byte, .ascii, etc.

Declared at: llvm/include/llvm/MC/MCObjectStreamer.h:135

Parameters

llvm::StringRef Data

void EmitCFISections(bool EH, bool Debug)

Declared at: llvm/include/llvm/MC/MCObjectStreamer.h:73

Parameters

bool EH
bool Debug

void EmitCVDefRangeDirective(
    ArrayRef<std::pair<const MCSymbol*,
                       const MCSymbol*>> Ranges,
    llvm::StringRef FixedSizePortion)

Description

This implements the CodeView '.cv_def_range' assembler directive.

Declared at: llvm/include/llvm/MC/MCObjectStreamer.h:162

Parameters

ArrayRef< std::pair<const MCSymbol*, const MCSymbol*>> Ranges
llvm::StringRef FixedSizePortion

void EmitCVFileChecksumOffsetDirective(
    unsigned int FileNo)

Description

This implements the CodeView '.cv_filechecksumoffset' assembler directive.

Declared at: llvm/include/llvm/MC/MCObjectStreamer.h:167

Parameters

unsigned int FileNo

void EmitCVFileChecksumsDirective()

Description

This implements the CodeView '.cv_filechecksums' assembler directive.

Declared at: llvm/include/llvm/MC/MCObjectStreamer.h:166

void EmitCVInlineLinetableDirective(
    unsigned int PrimaryFunctionId,
    unsigned int SourceFileId,
    unsigned int SourceLineNum,
    const llvm::MCSymbol* FnStartSym,
    const llvm::MCSymbol* FnEndSym)

Description

This implements the CodeView '.cv_inline_linetable' assembler directive.

Declared at: llvm/include/llvm/MC/MCObjectStreamer.h:157

Parameters

unsigned int PrimaryFunctionId
unsigned int SourceFileId
unsigned int SourceLineNum
const llvm::MCSymbol* FnStartSym
const llvm::MCSymbol* FnEndSym

void EmitCVLinetableDirective(
    unsigned int FunctionId,
    const llvm::MCSymbol* Begin,
    const llvm::MCSymbol* End)

Description

This implements the CodeView '.cv_linetable' assembler directive.

Declared at: llvm/include/llvm/MC/MCObjectStreamer.h:155

Parameters

unsigned int FunctionId
const llvm::MCSymbol* Begin
const llvm::MCSymbol* End

void EmitCVLocDirective(unsigned int FunctionId,
                        unsigned int FileNo,
                        unsigned int Line,
                        unsigned int Column,
                        bool PrologueEnd,
                        bool IsStmt,
                        llvm::StringRef FileName,
                        llvm::SMLoc Loc)

Description

This implements the CodeView '.cv_loc' assembler directive.

Declared at: llvm/include/llvm/MC/MCObjectStreamer.h:152

Parameters

unsigned int FunctionId
unsigned int FileNo
unsigned int Line
unsigned int Column
bool PrologueEnd
bool IsStmt
llvm::StringRef FileName
llvm::SMLoc Loc

void EmitCVStringTableDirective()

Description

This implements the CodeView '.cv_stringtable' assembler directive.

Declared at: llvm/include/llvm/MC/MCObjectStreamer.h:165

void EmitCodeAlignment(
    unsigned int ByteAlignment,
    unsigned int MaxBytesToEmit = 0)

Description

Emit nops until the byte alignment \p ByteAlignment is reached. This used to align code where the alignment bytes may be executed. This can emit different bytes for different sizes to optimize execution.

Declared at: llvm/include/llvm/MC/MCObjectStreamer.h:139

Parameters

unsigned int ByteAlignment
- The alignment to reach. This must be a power of two on some targets.
unsigned int MaxBytesToEmit = 0
- The maximum numbers of bytes to emit, or 0. If the alignment cannot be reached in this many bytes, no bytes are emitted.

void EmitDTPRel32Value(const llvm::MCExpr* Value)

Description

Emit the expression \p Value into the output as a dtprel (32-bit DTP relative) value. This is used to implement assembler directives such as .dtprelword on targets that support them.

Declared at: llvm/include/llvm/MC/MCObjectStreamer.h:168

Parameters

const llvm::MCExpr* Value

void EmitDTPRel64Value(const llvm::MCExpr* Value)

Description

Emit the expression \p Value into the output as a dtprel (64-bit DTP relative) value. This is used to implement assembler directives such as .dtpreldword on targets that support them.

Declared at: llvm/include/llvm/MC/MCObjectStreamer.h:169

Parameters

const llvm::MCExpr* Value

void EmitDwarfAdvanceFrameAddr(
    const llvm::MCSymbol* LastLabel,
    const llvm::MCSymbol* Label)

Declared at: llvm/include/llvm/MC/MCObjectStreamer.h:150

Parameters

const llvm::MCSymbol* LastLabel
const llvm::MCSymbol* Label

void EmitDwarfAdvanceLineAddr(
    int64_t LineDelta,
    const llvm::MCSymbol* LastLabel,
    const llvm::MCSymbol* Label,
    unsigned int PointerSize)

Declared at: llvm/include/llvm/MC/MCObjectStreamer.h:147

Parameters

int64_t LineDelta
const llvm::MCSymbol* LastLabel
const llvm::MCSymbol* Label
unsigned int PointerSize

void EmitDwarfLocDirective(
    unsigned int FileNo,
    unsigned int Line,
    unsigned int Column,
    unsigned int Flags,
    unsigned int Isa,
    unsigned int Discriminator,
    llvm::StringRef FileName)

Description

This implements the DWARF2 '.loc fileno lineno ...' assembler directive.

Declared at: llvm/include/llvm/MC/MCObjectStreamer.h:143

Parameters

unsigned int FileNo
unsigned int Line
unsigned int Column
unsigned int Flags
unsigned int Isa
unsigned int Discriminator
llvm::StringRef FileName

void EmitFileDirective(llvm::StringRef Filename)

Description

Switch to a new logical file. This is used to implement the '.file "foo.c"' assembler directive.

Declared at: llvm/include/llvm/MC/MCObjectStreamer.h:182

Parameters

llvm::StringRef Filename

void EmitFrames(llvm::MCAsmBackend* MAB)

Declared at: llvm/include/llvm/MC/MCObjectStreamer.h:72

Parameters

llvm::MCAsmBackend* MAB

void EmitGPRel32Value(const llvm::MCExpr* Value)

Description

Emit the expression \p Value into the output as a gprel32 (32-bit GP relative) value. This is used to implement assembler directives such as .gprel32 on targets that support them.

Declared at: llvm/include/llvm/MC/MCObjectStreamer.h:172

Parameters

const llvm::MCExpr* Value

void EmitGPRel64Value(const llvm::MCExpr* Value)

Description

Emit the expression \p Value into the output as a gprel64 (64-bit GP relative) value. This is used to implement assembler directives such as .gpdword on targets that support them.

Declared at: llvm/include/llvm/MC/MCObjectStreamer.h:173

Parameters

const llvm::MCExpr* Value

virtual void EmitInstToFragment(
    const llvm::MCInst& Inst,
    const llvm::MCSubtargetInfo&)

Description

Emit an instruction to a special fragment, because this instruction can change its size during relaxation.

Declared at: llvm/include/llvm/MC/MCObjectStreamer.h:130

Parameters

const llvm::MCInst& Inst
const llvm::MCSubtargetInfo& 

void EmitInstruction(
    const llvm::MCInst& Inst,
    const llvm::MCSubtargetInfo& STI)

Description

Emit the given \p Instruction into the current section.

Declared at: llvm/include/llvm/MC/MCObjectStreamer.h:126

Parameters

const llvm::MCInst& Inst
const llvm::MCSubtargetInfo& STI

void EmitLabel(llvm::MCSymbol* Symbol,
               llvm::SMLoc Loc = llvm::SMLoc())

Description

@ {

Declared at: llvm/include/llvm/MC/MCObjectStreamer.h:116

Parameters

llvm::MCSymbol* Symbol
llvm::SMLoc Loc = llvm::SMLoc()

virtual void EmitLabelAtPos(
    llvm::MCSymbol* Symbol,
    llvm::SMLoc Loc,
    llvm::MCFragment* F,
    uint64_t Offset)

Declared at: llvm/include/llvm/MC/MCObjectStreamer.h:117

Parameters

llvm::MCSymbol* Symbol
llvm::SMLoc Loc
llvm::MCFragment* F
uint64_t Offset

bool EmitRelocDirective(
    const llvm::MCExpr& Offset,
    llvm::StringRef Name,
    const llvm::MCExpr* Expr,
    llvm::SMLoc Loc,
    const llvm::MCSubtargetInfo& STI)

Description

Emit a .reloc directive. Returns true if the relocation could not be emitted because Name is not known.

Declared at: llvm/include/llvm/MC/MCObjectStreamer.h:174

Parameters

const llvm::MCExpr& Offset
llvm::StringRef Name
const llvm::MCExpr* Expr
llvm::SMLoc Loc
const llvm::MCSubtargetInfo& STI

void EmitSLEB128Value(const llvm::MCExpr* Value)

Declared at: llvm/include/llvm/MC/MCObjectStreamer.h:123

Parameters

const llvm::MCExpr* Value

void EmitTPRel32Value(const llvm::MCExpr* Value)

Description

Emit the expression \p Value into the output as a tprel (32-bit TP relative) value. This is used to implement assembler directives such as .tprelword on targets that support them.

Declared at: llvm/include/llvm/MC/MCObjectStreamer.h:170

Parameters

const llvm::MCExpr* Value

void EmitTPRel64Value(const llvm::MCExpr* Value)

Description

Emit the expression \p Value into the output as a tprel (64-bit TP relative) value. This is used to implement assembler directives such as .tpreldword on targets that support them.

Declared at: llvm/include/llvm/MC/MCObjectStreamer.h:171

Parameters

const llvm::MCExpr* Value

void EmitULEB128Value(const llvm::MCExpr* Value)

Declared at: llvm/include/llvm/MC/MCObjectStreamer.h:122

Parameters

const llvm::MCExpr* Value

void EmitValueImpl(
    const llvm::MCExpr* Value,
    unsigned int Size,
    llvm::SMLoc Loc = llvm::SMLoc())

Description

Emit the expression \p Value into the output as a native integer of the given \p Size bytes. This is used to implement assembler directives such as .word, .quad, etc.

Declared at: llvm/include/llvm/MC/MCObjectStreamer.h:120

Parameters

const llvm::MCExpr* Value
- The value to emit.
unsigned int Size
- The size of the integer (in bytes) to emit. This must match a native machine width.
llvm::SMLoc Loc = llvm::SMLoc()
- The location of the expression for error reporting.

void EmitValueToAlignment(
    unsigned int ByteAlignment,
    int64_t Value = 0,
    unsigned int ValueSize = 1,
    unsigned int MaxBytesToEmit = 0)

Description

Emit some number of copies of \p Value until the byte alignment \p ByteAlignment is reached. If the number of bytes need to emit for the alignment is not a multiple of \p ValueSize, then the contents of the emitted fill bytes is undefined. This used to implement the .align assembler directive.

Declared at: llvm/include/llvm/MC/MCObjectStreamer.h:136

Parameters

unsigned int ByteAlignment
- The alignment to reach. This must be a power of two on some targets.
int64_t Value = 0
- The value to use when filling bytes.
unsigned int ValueSize = 1
- The size of the integer (in bytes) to emit for\p Value. This must match a native machine width.
unsigned int MaxBytesToEmit = 0
- The maximum numbers of bytes to emit, or 0. If the alignment cannot be reached in this many bytes, no bytes are emitted.

void EmitWeakReference(
    llvm::MCSymbol* Alias,
    const llvm::MCSymbol* Symbol)

Description

Emit an weak reference from \p Alias to \p Symbol. This corresponds to an assembler statement such as: .weakref alias, symbol

Declared at: llvm/include/llvm/MC/MCObjectStreamer.h:124

Parameters

llvm::MCSymbol* Alias
- The alias that is being created.
const llvm::MCSymbol* Symbol
- The symbol being aliased.

void FinishImpl()

Description

Streamer specific finalization.

Declared at: llvm/include/llvm/MC/MCObjectStreamer.h:187

MCObjectStreamer(
    llvm::MCContext& Context,
    std::unique_ptr<MCAsmBackend> TAB,
    std::unique_ptr<MCObjectWriter> OW,
    std::unique_ptr<MCCodeEmitter> Emitter)

Declared at: llvm/include/llvm/MC/MCObjectStreamer.h:60

Parameters

llvm::MCContext& Context
std::unique_ptr<MCAsmBackend> TAB
std::unique_ptr<MCObjectWriter> OW
std::unique_ptr<MCCodeEmitter> Emitter

void addPendingLabel(llvm::MCSymbol* label)

Description

Assign a label to the current Section and Subsection even though a fragment is not yet present. Use flushPendingLabels(F) to associate a fragment with this label.

Declared at: llvm/include/llvm/MC/MCObjectStreamer.h:96

Parameters

llvm::MCSymbol* label

bool changeSectionImpl(
    llvm::MCSection* Section,
    const llvm::MCExpr* Subsection)

Declared at: llvm/include/llvm/MC/MCObjectStreamer.h:91

Parameters

llvm::MCSection* Section
const llvm::MCExpr* Subsection

void emitAbsoluteSymbolDiff(
    const llvm::MCSymbol* Hi,
    const llvm::MCSymbol* Lo,
    unsigned int Size)

Description

Emit the absolute difference between two symbols if possible. Emit the absolute difference between \c Hi and \c Lo, as long as we can compute it. Currently, that requires that both symbols are in the same data fragment and that the target has not specified that diff expressions require relocations to be emitted. Otherwise, do nothing and return\c false.

Declared at: llvm/include/llvm/MC/MCObjectStreamer.h:198

Parameters

const llvm::MCSymbol* Hi
const llvm::MCSymbol* Lo
unsigned int Size

void emitAbsoluteSymbolDiffAsULEB128(
    const llvm::MCSymbol* Hi,
    const llvm::MCSymbol* Lo)

Description

Emit the absolute difference between two symbols encoded with ULEB128.

Declared at: llvm/include/llvm/MC/MCObjectStreamer.h:201

Parameters

const llvm::MCSymbol* Hi
const llvm::MCSymbol* Lo

void emitFill(const llvm::MCExpr& NumBytes,
              uint64_t FillValue,
              llvm::SMLoc Loc = llvm::SMLoc())

Description

Emit \p Size bytes worth of the value specified by \p FillValue. This is used to implement assembler directives such as .space or .skip.

Declared at: llvm/include/llvm/MC/MCObjectStreamer.h:178

Parameters

const llvm::MCExpr& NumBytes
- The number of bytes to emit.
uint64_t FillValue
- The value to use when filling bytes.
llvm::SMLoc Loc = llvm::SMLoc()
- The location of the expression for error reporting.

void emitFill(const llvm::MCExpr& NumValues,
              int64_t Size,
              int64_t Expr,
              llvm::SMLoc Loc = llvm::SMLoc())

Description

Emit \p NumValues copies of \p Size bytes. Each \p Size bytes is taken from the lowest order 4 bytes of \p Expr expression. This is used to implement assembler directives such as .fill.

Declared at: llvm/include/llvm/MC/MCObjectStreamer.h:180

Parameters

const llvm::MCExpr& NumValues
- The number of copies of \p Size bytes to emit.
int64_t Size
- The size (in bytes) of each repeated value.
int64_t Expr
- The expression from which \p Size bytes are used.
llvm::SMLoc Loc = llvm::SMLoc()

void emitValueToOffset(const llvm::MCExpr* Offset,
                       unsigned char Value,
                       llvm::SMLoc Loc)

Description

Emit some number of copies of \p Value until the byte offset \p Offset is reached. This is used to implement assembler directives such as .org.

Declared at: llvm/include/llvm/MC/MCObjectStreamer.h:141

Parameters

const llvm::MCExpr* Offset
- The offset to reach. This may be an expression, but the expression must be associated with the current section.
unsigned char Value
- The value to use when filling bytes.
llvm::SMLoc Loc

void flushPendingLabels()

Description

Create a data fragment for any pending labels across all Sections and Subsections.

Declared at: llvm/include/llvm/MC/MCObjectStreamer.h:109

void flushPendingLabels(llvm::MCFragment* F,
                        uint64_t FOffset = 0)

Description

If any labels have been emitted but not assigned fragments in the current Section and Subsection, ensure that they get assigned, either to fragment F if possible or to a new data fragment. Optionally, one can provide an offset \p FOffset as a symbol offset within the fragment.

Declared at: llvm/include/llvm/MC/MCObjectStreamer.h:102

Parameters

llvm::MCFragment* F
uint64_t FOffset = 0

llvm::MCAssembler& getAssembler()

Declared at: llvm/include/llvm/MC/MCObjectStreamer.h:111

llvm::MCAssembler* getAssemblerPtr()

Declared at: llvm/include/llvm/MC/MCObjectStreamer.h:112

llvm::MCFragment* getCurrentFragment() const

Declared at: llvm/include/llvm/MC/MCObjectStreamer.h:75

llvm::MCDataFragment* getOrCreateDataFragment(
    const llvm::MCSubtargetInfo* STI = nullptr)

Description

Get a data fragment to write into, creating a new one if the current fragment is not a data fragment. Optionally a \p STI can be passed in so that a new fragment is created if the Subtarget differs from the current fragment.

Declared at: llvm/include/llvm/MC/MCObjectStreamer.h:88

Parameters

const llvm::MCSubtargetInfo* STI = nullptr

void insert(llvm::MCFragment* F)

Declared at: llvm/include/llvm/MC/MCObjectStreamer.h:77

Parameters

llvm::MCFragment* F

bool isIntegratedAssemblerRequired() const

Description

Object streamers require the integrated assembler.

Declared at: llvm/include/llvm/MC/MCObjectStreamer.h:70

bool mayHaveInstructions(
    llvm::MCSection& Sec) const

Declared at: llvm/include/llvm/MC/MCObjectStreamer.h:204

Parameters

llvm::MCSection& Sec

void reset()

Description

state management

Declared at: llvm/include/llvm/MC/MCObjectStreamer.h:67

void visitUsedSymbol(const llvm::MCSymbol& Sym)

Declared at: llvm/include/llvm/MC/MCObjectStreamer.h:105

Parameters

const llvm::MCSymbol& Sym

~MCObjectStreamer()

Declared at: llvm/include/llvm/MC/MCObjectStreamer.h:63