1 //===- lib/MC/MCStreamer.cpp - Streaming Machine Code Output --------------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 #include "llvm/MC/MCStreamer.h"
11 #include "llvm/ADT/SmallString.h"
12 #include "llvm/ADT/Twine.h"
13 #include "llvm/MC/MCAsmBackend.h"
14 #include "llvm/MC/MCAsmInfo.h"
15 #include "llvm/MC/MCContext.h"
16 #include "llvm/MC/MCExpr.h"
17 #include "llvm/MC/MCInst.h"
18 #include "llvm/MC/MCObjectFileInfo.h"
19 #include "llvm/MC/MCObjectWriter.h"
20 #include "llvm/MC/MCSection.h"
21 #include "llvm/MC/MCSymbol.h"
22 #include "llvm/MC/MCWin64EH.h"
23 #include "llvm/Support/ErrorHandling.h"
24 #include "llvm/Support/LEB128.h"
25 #include "llvm/Support/raw_ostream.h"
29 // Pin the vtables to this file.
30 MCTargetStreamer::~MCTargetStreamer() {}
32 MCTargetStreamer::MCTargetStreamer(MCStreamer &S) : Streamer(S) {
33 S.setTargetStreamer(this);
36 void MCTargetStreamer::emitLabel(MCSymbol *Symbol) {}
38 void MCTargetStreamer::finish() {}
40 void MCTargetStreamer::emitAssignment(MCSymbol *Symbol, const MCExpr *Value) {}
42 MCStreamer::MCStreamer(MCContext &Ctx)
43 : Context(Ctx), CurrentWinFrameInfo(nullptr) {
44 SectionStack.push_back(std::pair<MCSectionSubPair, MCSectionSubPair>());
47 MCStreamer::~MCStreamer() {
48 for (unsigned i = 0; i < getNumWinFrameInfos(); ++i)
49 delete WinFrameInfos[i];
52 void MCStreamer::reset() {
53 DwarfFrameInfos.clear();
54 for (unsigned i = 0; i < getNumWinFrameInfos(); ++i)
55 delete WinFrameInfos[i];
56 WinFrameInfos.clear();
57 CurrentWinFrameInfo = nullptr;
58 SymbolOrdering.clear();
60 SectionStack.push_back(std::pair<MCSectionSubPair, MCSectionSubPair>());
63 raw_ostream &MCStreamer::GetCommentOS() {
64 // By default, discard comments.
68 void MCStreamer::emitRawComment(const Twine &T, bool TabPrefix) {}
70 void MCStreamer::generateCompactUnwindEncodings(MCAsmBackend *MAB) {
71 for (auto &FI : DwarfFrameInfos)
72 FI.CompactUnwindEncoding =
73 (MAB ? MAB->generateCompactUnwindEncoding(FI.Instructions) : 0);
76 /// EmitIntValue - Special case of EmitValue that avoids the client having to
77 /// pass in a MCExpr for constant integers.
78 void MCStreamer::EmitIntValue(uint64_t Value, unsigned Size) {
79 assert(1 <= Size && Size <= 8 && "Invalid size");
80 assert((isUIntN(8 * Size, Value) || isIntN(8 * Size, Value)) &&
83 const bool isLittleEndian = Context.getAsmInfo()->isLittleEndian();
84 for (unsigned i = 0; i != Size; ++i) {
85 unsigned index = isLittleEndian ? i : (Size - i - 1);
86 buf[i] = uint8_t(Value >> (index * 8));
88 EmitBytes(StringRef(buf, Size));
91 /// EmitULEB128Value - Special case of EmitULEB128Value that avoids the
92 /// client having to pass in a MCExpr for constant integers.
93 void MCStreamer::EmitULEB128IntValue(uint64_t Value, unsigned Padding) {
95 raw_svector_ostream OSE(Tmp);
96 encodeULEB128(Value, OSE, Padding);
100 /// EmitSLEB128Value - Special case of EmitSLEB128Value that avoids the
101 /// client having to pass in a MCExpr for constant integers.
102 void MCStreamer::EmitSLEB128IntValue(int64_t Value) {
103 SmallString<128> Tmp;
104 raw_svector_ostream OSE(Tmp);
105 encodeSLEB128(Value, OSE);
106 EmitBytes(OSE.str());
109 void MCStreamer::EmitValue(const MCExpr *Value, unsigned Size,
111 EmitValueImpl(Value, Size, Loc);
114 void MCStreamer::EmitSymbolValue(const MCSymbol *Sym, unsigned Size,
115 bool IsSectionRelative) {
116 assert((!IsSectionRelative || Size == 4) &&
117 "SectionRelative value requires 4-bytes");
119 if (!IsSectionRelative)
120 EmitValueImpl(MCSymbolRefExpr::Create(Sym, getContext()), Size);
122 EmitCOFFSecRel32(Sym);
125 void MCStreamer::EmitGPRel64Value(const MCExpr *Value) {
126 report_fatal_error("unsupported directive in streamer");
129 void MCStreamer::EmitGPRel32Value(const MCExpr *Value) {
130 report_fatal_error("unsupported directive in streamer");
133 /// EmitFill - Emit NumBytes bytes worth of the value specified by
134 /// FillValue. This implements directives such as '.space'.
135 void MCStreamer::EmitFill(uint64_t NumBytes, uint8_t FillValue) {
136 const MCExpr *E = MCConstantExpr::Create(FillValue, getContext());
137 for (uint64_t i = 0, e = NumBytes; i != e; ++i)
141 /// The implementation in this class just redirects to EmitFill.
142 void MCStreamer::EmitZeros(uint64_t NumBytes) {
143 EmitFill(NumBytes, 0);
146 unsigned MCStreamer::EmitDwarfFileDirective(unsigned FileNo,
148 StringRef Filename, unsigned CUID) {
149 return getContext().GetDwarfFile(Directory, Filename, FileNo, CUID);
152 void MCStreamer::EmitDwarfLocDirective(unsigned FileNo, unsigned Line,
153 unsigned Column, unsigned Flags,
155 unsigned Discriminator,
156 StringRef FileName) {
157 getContext().setCurrentDwarfLoc(FileNo, Line, Column, Flags, Isa,
161 MCSymbol *MCStreamer::getDwarfLineTableSymbol(unsigned CUID) {
162 MCDwarfLineTable &Table = getContext().getMCDwarfLineTable(CUID);
163 if (!Table.getLabel()) {
164 StringRef Prefix = Context.getAsmInfo()->getPrivateGlobalPrefix();
166 Context.GetOrCreateSymbol(Prefix + "line_table_start" + Twine(CUID)));
168 return Table.getLabel();
171 MCDwarfFrameInfo *MCStreamer::getCurrentDwarfFrameInfo() {
172 if (DwarfFrameInfos.empty())
174 return &DwarfFrameInfos.back();
177 void MCStreamer::EnsureValidDwarfFrame() {
178 MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo();
179 if (!CurFrame || CurFrame->End)
180 report_fatal_error("No open frame");
183 void MCStreamer::EmitEHSymAttributes(const MCSymbol *Symbol,
184 MCSymbol *EHSymbol) {
187 void MCStreamer::InitSections(bool NoExecStack) {
188 SwitchSection(getContext().getObjectFileInfo()->getTextSection());
191 void MCStreamer::AssignSection(MCSymbol *Symbol, const MCSection *Section) {
193 Symbol->setSection(*Section);
195 Symbol->setUndefined();
197 // As we emit symbols into a section, track the order so that they can
198 // be sorted upon later. Zero is reserved to mean 'unemitted'.
199 SymbolOrdering[Symbol] = 1 + SymbolOrdering.size();
202 void MCStreamer::EmitLabel(MCSymbol *Symbol) {
203 assert(!Symbol->isVariable() && "Cannot emit a variable symbol!");
204 assert(getCurrentSection().first && "Cannot emit before setting section!");
205 AssignSection(Symbol, getCurrentSection().first);
207 MCTargetStreamer *TS = getTargetStreamer();
209 TS->emitLabel(Symbol);
212 void MCStreamer::EmitCFISections(bool EH, bool Debug) {
216 void MCStreamer::EmitCFIStartProc(bool IsSimple) {
217 MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo();
218 if (CurFrame && !CurFrame->End)
219 report_fatal_error("Starting a frame before finishing the previous one!");
221 MCDwarfFrameInfo Frame;
222 Frame.IsSimple = IsSimple;
223 EmitCFIStartProcImpl(Frame);
225 const MCAsmInfo* MAI = Context.getAsmInfo();
227 for (const MCCFIInstruction& Inst : MAI->getInitialFrameState()) {
228 if (Inst.getOperation() == MCCFIInstruction::OpDefCfa ||
229 Inst.getOperation() == MCCFIInstruction::OpDefCfaRegister) {
230 Frame.CurrentCfaRegister = Inst.getRegister();
235 DwarfFrameInfos.push_back(Frame);
238 void MCStreamer::EmitCFIStartProcImpl(MCDwarfFrameInfo &Frame) {
241 void MCStreamer::EmitCFIEndProc() {
242 EnsureValidDwarfFrame();
243 MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo();
244 EmitCFIEndProcImpl(*CurFrame);
247 void MCStreamer::EmitCFIEndProcImpl(MCDwarfFrameInfo &Frame) {
248 // Put a dummy non-null value in Frame.End to mark that this frame has been
250 Frame.End = (MCSymbol *) 1;
253 MCSymbol *MCStreamer::EmitCFICommon() {
254 EnsureValidDwarfFrame();
255 MCSymbol *Label = getContext().CreateTempSymbol();
260 void MCStreamer::EmitCFIDefCfa(int64_t Register, int64_t Offset) {
261 MCSymbol *Label = EmitCFICommon();
262 MCCFIInstruction Instruction =
263 MCCFIInstruction::createDefCfa(Label, Register, Offset);
264 MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo();
265 CurFrame->Instructions.push_back(Instruction);
266 CurFrame->CurrentCfaRegister = static_cast<unsigned>(Register);
269 void MCStreamer::EmitCFIDefCfaOffset(int64_t Offset) {
270 MCSymbol *Label = EmitCFICommon();
271 MCCFIInstruction Instruction =
272 MCCFIInstruction::createDefCfaOffset(Label, Offset);
273 MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo();
274 CurFrame->Instructions.push_back(Instruction);
277 void MCStreamer::EmitCFIAdjustCfaOffset(int64_t Adjustment) {
278 MCSymbol *Label = EmitCFICommon();
279 MCCFIInstruction Instruction =
280 MCCFIInstruction::createAdjustCfaOffset(Label, Adjustment);
281 MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo();
282 CurFrame->Instructions.push_back(Instruction);
285 void MCStreamer::EmitCFIDefCfaRegister(int64_t Register) {
286 MCSymbol *Label = EmitCFICommon();
287 MCCFIInstruction Instruction =
288 MCCFIInstruction::createDefCfaRegister(Label, Register);
289 MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo();
290 CurFrame->Instructions.push_back(Instruction);
291 CurFrame->CurrentCfaRegister = static_cast<unsigned>(Register);
294 void MCStreamer::EmitCFIOffset(int64_t Register, int64_t Offset) {
295 MCSymbol *Label = EmitCFICommon();
296 MCCFIInstruction Instruction =
297 MCCFIInstruction::createOffset(Label, Register, Offset);
298 MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo();
299 CurFrame->Instructions.push_back(Instruction);
302 void MCStreamer::EmitCFIRelOffset(int64_t Register, int64_t Offset) {
303 MCSymbol *Label = EmitCFICommon();
304 MCCFIInstruction Instruction =
305 MCCFIInstruction::createRelOffset(Label, Register, Offset);
306 MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo();
307 CurFrame->Instructions.push_back(Instruction);
310 void MCStreamer::EmitCFIPersonality(const MCSymbol *Sym,
312 EnsureValidDwarfFrame();
313 MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo();
314 CurFrame->Personality = Sym;
315 CurFrame->PersonalityEncoding = Encoding;
318 void MCStreamer::EmitCFILsda(const MCSymbol *Sym, unsigned Encoding) {
319 EnsureValidDwarfFrame();
320 MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo();
321 CurFrame->Lsda = Sym;
322 CurFrame->LsdaEncoding = Encoding;
325 void MCStreamer::EmitCFIRememberState() {
326 MCSymbol *Label = EmitCFICommon();
327 MCCFIInstruction Instruction = MCCFIInstruction::createRememberState(Label);
328 MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo();
329 CurFrame->Instructions.push_back(Instruction);
332 void MCStreamer::EmitCFIRestoreState() {
333 // FIXME: Error if there is no matching cfi_remember_state.
334 MCSymbol *Label = EmitCFICommon();
335 MCCFIInstruction Instruction = MCCFIInstruction::createRestoreState(Label);
336 MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo();
337 CurFrame->Instructions.push_back(Instruction);
340 void MCStreamer::EmitCFISameValue(int64_t Register) {
341 MCSymbol *Label = EmitCFICommon();
342 MCCFIInstruction Instruction =
343 MCCFIInstruction::createSameValue(Label, Register);
344 MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo();
345 CurFrame->Instructions.push_back(Instruction);
348 void MCStreamer::EmitCFIRestore(int64_t Register) {
349 MCSymbol *Label = EmitCFICommon();
350 MCCFIInstruction Instruction =
351 MCCFIInstruction::createRestore(Label, Register);
352 MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo();
353 CurFrame->Instructions.push_back(Instruction);
356 void MCStreamer::EmitCFIEscape(StringRef Values) {
357 MCSymbol *Label = EmitCFICommon();
358 MCCFIInstruction Instruction = MCCFIInstruction::createEscape(Label, Values);
359 MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo();
360 CurFrame->Instructions.push_back(Instruction);
363 void MCStreamer::EmitCFISignalFrame() {
364 EnsureValidDwarfFrame();
365 MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo();
366 CurFrame->IsSignalFrame = true;
369 void MCStreamer::EmitCFIUndefined(int64_t Register) {
370 MCSymbol *Label = EmitCFICommon();
371 MCCFIInstruction Instruction =
372 MCCFIInstruction::createUndefined(Label, Register);
373 MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo();
374 CurFrame->Instructions.push_back(Instruction);
377 void MCStreamer::EmitCFIRegister(int64_t Register1, int64_t Register2) {
378 MCSymbol *Label = EmitCFICommon();
379 MCCFIInstruction Instruction =
380 MCCFIInstruction::createRegister(Label, Register1, Register2);
381 MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo();
382 CurFrame->Instructions.push_back(Instruction);
385 void MCStreamer::EmitCFIWindowSave() {
386 MCSymbol *Label = EmitCFICommon();
387 MCCFIInstruction Instruction =
388 MCCFIInstruction::createWindowSave(Label);
389 MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo();
390 CurFrame->Instructions.push_back(Instruction);
393 void MCStreamer::EnsureValidWinFrameInfo() {
394 if (!CurrentWinFrameInfo || CurrentWinFrameInfo->End)
395 report_fatal_error("No open Win64 EH frame function!");
398 void MCStreamer::EmitWinCFIStartProc(const MCSymbol *Symbol) {
399 if (CurrentWinFrameInfo && !CurrentWinFrameInfo->End)
400 report_fatal_error("Starting a function before ending the previous one!");
402 MCSymbol *StartProc = getContext().CreateTempSymbol();
403 EmitLabel(StartProc);
405 WinFrameInfos.push_back(new WinEH::FrameInfo(Symbol, StartProc));
406 CurrentWinFrameInfo = WinFrameInfos.back();
409 void MCStreamer::EmitWinCFIEndProc() {
410 EnsureValidWinFrameInfo();
411 if (CurrentWinFrameInfo->ChainedParent)
412 report_fatal_error("Not all chained regions terminated!");
414 MCSymbol *Label = getContext().CreateTempSymbol();
416 CurrentWinFrameInfo->End = Label;
419 void MCStreamer::EmitWinCFIStartChained() {
420 EnsureValidWinFrameInfo();
422 MCSymbol *StartProc = getContext().CreateTempSymbol();
423 EmitLabel(StartProc);
425 WinFrameInfos.push_back(new WinEH::FrameInfo(CurrentWinFrameInfo->Function,
426 StartProc, CurrentWinFrameInfo));
427 CurrentWinFrameInfo = WinFrameInfos.back();
430 void MCStreamer::EmitWinCFIEndChained() {
431 EnsureValidWinFrameInfo();
432 if (!CurrentWinFrameInfo->ChainedParent)
433 report_fatal_error("End of a chained region outside a chained region!");
435 MCSymbol *Label = getContext().CreateTempSymbol();
438 CurrentWinFrameInfo->End = Label;
439 CurrentWinFrameInfo =
440 const_cast<WinEH::FrameInfo *>(CurrentWinFrameInfo->ChainedParent);
443 void MCStreamer::EmitWinEHHandler(const MCSymbol *Sym, bool Unwind,
445 EnsureValidWinFrameInfo();
446 if (CurrentWinFrameInfo->ChainedParent)
447 report_fatal_error("Chained unwind areas can't have handlers!");
448 CurrentWinFrameInfo->ExceptionHandler = Sym;
449 if (!Except && !Unwind)
450 report_fatal_error("Don't know what kind of handler this is!");
452 CurrentWinFrameInfo->HandlesUnwind = true;
454 CurrentWinFrameInfo->HandlesExceptions = true;
457 void MCStreamer::EmitWinEHHandlerData() {
458 EnsureValidWinFrameInfo();
459 if (CurrentWinFrameInfo->ChainedParent)
460 report_fatal_error("Chained unwind areas can't have handlers!");
463 void MCStreamer::EmitWinCFIPushReg(unsigned Register) {
464 EnsureValidWinFrameInfo();
466 MCSymbol *Label = getContext().CreateTempSymbol();
469 WinEH::Instruction Inst = Win64EH::Instruction::PushNonVol(Label, Register);
470 CurrentWinFrameInfo->Instructions.push_back(Inst);
473 void MCStreamer::EmitWinCFISetFrame(unsigned Register, unsigned Offset) {
474 EnsureValidWinFrameInfo();
475 if (CurrentWinFrameInfo->LastFrameInst >= 0)
476 report_fatal_error("Frame register and offset already specified!");
478 report_fatal_error("Misaligned frame pointer offset!");
480 report_fatal_error("Frame offset must be less than or equal to 240!");
482 MCSymbol *Label = getContext().CreateTempSymbol();
485 WinEH::Instruction Inst =
486 Win64EH::Instruction::SetFPReg(Label, Register, Offset);
487 CurrentWinFrameInfo->LastFrameInst = CurrentWinFrameInfo->Instructions.size();
488 CurrentWinFrameInfo->Instructions.push_back(Inst);
491 void MCStreamer::EmitWinCFIAllocStack(unsigned Size) {
492 EnsureValidWinFrameInfo();
494 report_fatal_error("Allocation size must be non-zero!");
496 report_fatal_error("Misaligned stack allocation!");
498 MCSymbol *Label = getContext().CreateTempSymbol();
501 WinEH::Instruction Inst = Win64EH::Instruction::Alloc(Label, Size);
502 CurrentWinFrameInfo->Instructions.push_back(Inst);
505 void MCStreamer::EmitWinCFISaveReg(unsigned Register, unsigned Offset) {
506 EnsureValidWinFrameInfo();
508 report_fatal_error("Misaligned saved register offset!");
510 MCSymbol *Label = getContext().CreateTempSymbol();
513 WinEH::Instruction Inst =
514 Win64EH::Instruction::SaveNonVol(Label, Register, Offset);
515 CurrentWinFrameInfo->Instructions.push_back(Inst);
518 void MCStreamer::EmitWinCFISaveXMM(unsigned Register, unsigned Offset) {
519 EnsureValidWinFrameInfo();
521 report_fatal_error("Misaligned saved vector register offset!");
523 MCSymbol *Label = getContext().CreateTempSymbol();
526 WinEH::Instruction Inst =
527 Win64EH::Instruction::SaveXMM(Label, Register, Offset);
528 CurrentWinFrameInfo->Instructions.push_back(Inst);
531 void MCStreamer::EmitWinCFIPushFrame(bool Code) {
532 EnsureValidWinFrameInfo();
533 if (CurrentWinFrameInfo->Instructions.size() > 0)
534 report_fatal_error("If present, PushMachFrame must be the first UOP");
536 MCSymbol *Label = getContext().CreateTempSymbol();
539 WinEH::Instruction Inst = Win64EH::Instruction::PushMachFrame(Label, Code);
540 CurrentWinFrameInfo->Instructions.push_back(Inst);
543 void MCStreamer::EmitWinCFIEndProlog() {
544 EnsureValidWinFrameInfo();
546 MCSymbol *Label = getContext().CreateTempSymbol();
549 CurrentWinFrameInfo->PrologEnd = Label;
552 void MCStreamer::EmitCOFFSectionIndex(MCSymbol const *Symbol) {
555 void MCStreamer::EmitCOFFSecRel32(MCSymbol const *Symbol) {
558 /// EmitRawText - If this file is backed by an assembly streamer, this dumps
559 /// the specified string in the output .s file. This capability is
560 /// indicated by the hasRawTextSupport() predicate.
561 void MCStreamer::EmitRawTextImpl(StringRef String) {
562 errs() << "EmitRawText called on an MCStreamer that doesn't support it, "
563 " something must not be fully mc'ized\n";
567 void MCStreamer::EmitRawText(const Twine &T) {
568 SmallString<128> Str;
569 EmitRawTextImpl(T.toStringRef(Str));
572 void MCStreamer::EmitWindowsUnwindTables() {
575 void MCStreamer::Finish() {
576 if (!DwarfFrameInfos.empty() && !DwarfFrameInfos.back().End)
577 report_fatal_error("Unfinished frame!");
579 MCTargetStreamer *TS = getTargetStreamer();
586 void MCStreamer::EmitAssignment(MCSymbol *Symbol, const MCExpr *Value) {
587 visitUsedExpr(*Value);
588 Symbol->setVariableValue(Value);
590 MCTargetStreamer *TS = getTargetStreamer();
592 TS->emitAssignment(Symbol, Value);
595 void MCStreamer::visitUsedSymbol(const MCSymbol &Sym) {
598 void MCStreamer::visitUsedExpr(const MCExpr &Expr) {
599 switch (Expr.getKind()) {
601 cast<MCTargetExpr>(Expr).visitUsedExpr(*this);
604 case MCExpr::Constant:
607 case MCExpr::Binary: {
608 const MCBinaryExpr &BE = cast<MCBinaryExpr>(Expr);
609 visitUsedExpr(*BE.getLHS());
610 visitUsedExpr(*BE.getRHS());
614 case MCExpr::SymbolRef:
615 visitUsedSymbol(cast<MCSymbolRefExpr>(Expr).getSymbol());
619 visitUsedExpr(*cast<MCUnaryExpr>(Expr).getSubExpr());
624 void MCStreamer::EmitInstruction(const MCInst &Inst,
625 const MCSubtargetInfo &STI) {
627 for (unsigned i = Inst.getNumOperands(); i--;)
628 if (Inst.getOperand(i).isExpr())
629 visitUsedExpr(*Inst.getOperand(i).getExpr());
632 void MCStreamer::EmitAssemblerFlag(MCAssemblerFlag Flag) {}
633 void MCStreamer::EmitThumbFunc(MCSymbol *Func) {}
634 void MCStreamer::EmitSymbolDesc(MCSymbol *Symbol, unsigned DescValue) {}
635 void MCStreamer::BeginCOFFSymbolDef(const MCSymbol *Symbol) {}
636 void MCStreamer::EndCOFFSymbolDef() {}
637 void MCStreamer::EmitFileDirective(StringRef Filename) {}
638 void MCStreamer::EmitCOFFSymbolStorageClass(int StorageClass) {}
639 void MCStreamer::EmitCOFFSymbolType(int Type) {}
640 void MCStreamer::EmitELFSize(MCSymbol *Symbol, const MCExpr *Value) {}
641 void MCStreamer::EmitLocalCommonSymbol(MCSymbol *Symbol, uint64_t Size,
642 unsigned ByteAlignment) {}
643 void MCStreamer::EmitTBSSSymbol(const MCSection *Section, MCSymbol *Symbol,
644 uint64_t Size, unsigned ByteAlignment) {}
645 void MCStreamer::ChangeSection(const MCSection *, const MCExpr *) {}
646 void MCStreamer::EmitWeakReference(MCSymbol *Alias, const MCSymbol *Symbol) {}
647 void MCStreamer::EmitBytes(StringRef Data) {}
648 void MCStreamer::EmitValueImpl(const MCExpr *Value, unsigned Size,
650 visitUsedExpr(*Value);
652 void MCStreamer::EmitULEB128Value(const MCExpr *Value) {}
653 void MCStreamer::EmitSLEB128Value(const MCExpr *Value) {}
654 void MCStreamer::EmitValueToAlignment(unsigned ByteAlignment, int64_t Value,
656 unsigned MaxBytesToEmit) {}
657 void MCStreamer::EmitCodeAlignment(unsigned ByteAlignment,
658 unsigned MaxBytesToEmit) {}
659 bool MCStreamer::EmitValueToOffset(const MCExpr *Offset, unsigned char Value) {
662 void MCStreamer::EmitBundleAlignMode(unsigned AlignPow2) {}
663 void MCStreamer::EmitBundleLock(bool AlignToEnd) {}
664 void MCStreamer::FinishImpl() {}
665 void MCStreamer::EmitBundleUnlock() {}
667 void MCStreamer::SwitchSection(const MCSection *Section,
668 const MCExpr *Subsection) {
669 assert(Section && "Cannot switch to a null section!");
670 MCSectionSubPair curSection = SectionStack.back().first;
671 SectionStack.back().second = curSection;
672 if (MCSectionSubPair(Section, Subsection) != curSection) {
673 SectionStack.back().first = MCSectionSubPair(Section, Subsection);
674 assert(!Section->hasEnded() && "Section already ended");
675 ChangeSection(Section, Subsection);
676 MCSymbol *Sym = Section->getBeginSymbol();
677 if (Sym && !Sym->isInSection())
682 MCSymbol *MCStreamer::endSection(const MCSection *Section) {
683 // TODO: keep track of the last subsection so that this symbol appears in the
685 MCSymbol *Sym = Section->getEndSymbol(Context);
686 if (Sym->isInSection())
689 SwitchSection(Section);