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/MCInstPrinter.h"
19 #include "llvm/MC/MCObjectFileInfo.h"
20 #include "llvm/MC/MCObjectWriter.h"
21 #include "llvm/MC/MCSection.h"
22 #include "llvm/MC/MCSymbol.h"
23 #include "llvm/MC/MCWin64EH.h"
24 #include "llvm/Support/ErrorHandling.h"
25 #include "llvm/Support/LEB128.h"
26 #include "llvm/Support/raw_ostream.h"
30 // Pin the vtables to this file.
31 MCTargetStreamer::~MCTargetStreamer() {}
33 MCTargetStreamer::MCTargetStreamer(MCStreamer &S) : Streamer(S) {
34 S.setTargetStreamer(this);
37 void MCTargetStreamer::emitLabel(MCSymbol *Symbol) {}
39 void MCTargetStreamer::finish() {}
41 void MCTargetStreamer::emitAssignment(MCSymbol *Symbol, const MCExpr *Value) {}
43 MCStreamer::MCStreamer(MCContext &Ctx)
44 : Context(Ctx), CurrentWinFrameInfo(nullptr) {
45 SectionStack.push_back(std::pair<MCSectionSubPair, MCSectionSubPair>());
48 MCStreamer::~MCStreamer() {
49 for (unsigned i = 0; i < getNumWinFrameInfos(); ++i)
50 delete WinFrameInfos[i];
53 void MCStreamer::reset() {
54 DwarfFrameInfos.clear();
55 for (unsigned i = 0; i < getNumWinFrameInfos(); ++i)
56 delete WinFrameInfos[i];
57 WinFrameInfos.clear();
58 CurrentWinFrameInfo = nullptr;
59 SymbolOrdering.clear();
61 SectionStack.push_back(std::pair<MCSectionSubPair, MCSectionSubPair>());
64 raw_ostream &MCStreamer::GetCommentOS() {
65 // By default, discard comments.
69 void MCStreamer::emitRawComment(const Twine &T, bool TabPrefix) {}
71 void MCStreamer::generateCompactUnwindEncodings(MCAsmBackend *MAB) {
72 for (auto &FI : DwarfFrameInfos)
73 FI.CompactUnwindEncoding =
74 (MAB ? MAB->generateCompactUnwindEncoding(FI.Instructions) : 0);
77 /// EmitIntValue - Special case of EmitValue that avoids the client having to
78 /// pass in a MCExpr for constant integers.
79 void MCStreamer::EmitIntValue(uint64_t Value, unsigned Size) {
80 assert(1 <= Size && Size <= 8 && "Invalid size");
81 assert((isUIntN(8 * Size, Value) || isIntN(8 * Size, Value)) &&
84 const bool isLittleEndian = Context.getAsmInfo()->isLittleEndian();
85 for (unsigned i = 0; i != Size; ++i) {
86 unsigned index = isLittleEndian ? i : (Size - i - 1);
87 buf[i] = uint8_t(Value >> (index * 8));
89 EmitBytes(StringRef(buf, Size));
92 /// EmitULEB128Value - Special case of EmitULEB128Value that avoids the
93 /// client having to pass in a MCExpr for constant integers.
94 void MCStreamer::EmitULEB128IntValue(uint64_t Value, unsigned Padding) {
96 raw_svector_ostream OSE(Tmp);
97 encodeULEB128(Value, OSE, Padding);
101 /// EmitSLEB128Value - Special case of EmitSLEB128Value that avoids the
102 /// client having to pass in a MCExpr for constant integers.
103 void MCStreamer::EmitSLEB128IntValue(int64_t Value) {
104 SmallString<128> Tmp;
105 raw_svector_ostream OSE(Tmp);
106 encodeSLEB128(Value, OSE);
107 EmitBytes(OSE.str());
110 void MCStreamer::EmitValue(const MCExpr *Value, unsigned Size, SMLoc Loc) {
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, MCSection *Section) {
193 Symbol->setSection(*Section);
195 // As we emit symbols into a section, track the order so that they can
196 // be sorted upon later. Zero is reserved to mean 'unemitted'.
197 SymbolOrdering[Symbol] = 1 + SymbolOrdering.size();
200 void MCStreamer::EmitLabel(MCSymbol *Symbol) {
201 assert(!Symbol->isVariable() && "Cannot emit a variable symbol!");
202 assert(getCurrentSection().first && "Cannot emit before setting section!");
203 AssignSection(Symbol, getCurrentSection().first);
205 MCTargetStreamer *TS = getTargetStreamer();
207 TS->emitLabel(Symbol);
210 void MCStreamer::EmitCFISections(bool EH, bool Debug) {
214 void MCStreamer::EmitCFIStartProc(bool IsSimple) {
215 MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo();
216 if (CurFrame && !CurFrame->End)
217 report_fatal_error("Starting a frame before finishing the previous one!");
219 MCDwarfFrameInfo Frame;
220 Frame.IsSimple = IsSimple;
221 EmitCFIStartProcImpl(Frame);
223 const MCAsmInfo* MAI = Context.getAsmInfo();
225 for (const MCCFIInstruction& Inst : MAI->getInitialFrameState()) {
226 if (Inst.getOperation() == MCCFIInstruction::OpDefCfa ||
227 Inst.getOperation() == MCCFIInstruction::OpDefCfaRegister) {
228 Frame.CurrentCfaRegister = Inst.getRegister();
233 DwarfFrameInfos.push_back(Frame);
236 void MCStreamer::EmitCFIStartProcImpl(MCDwarfFrameInfo &Frame) {
239 void MCStreamer::EmitCFIEndProc() {
240 EnsureValidDwarfFrame();
241 MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo();
242 EmitCFIEndProcImpl(*CurFrame);
245 void MCStreamer::EmitCFIEndProcImpl(MCDwarfFrameInfo &Frame) {
246 // Put a dummy non-null value in Frame.End to mark that this frame has been
248 Frame.End = (MCSymbol *) 1;
251 MCSymbol *MCStreamer::EmitCFICommon() {
252 EnsureValidDwarfFrame();
253 MCSymbol *Label = getContext().createTempSymbol();
258 void MCStreamer::EmitCFIDefCfa(int64_t Register, int64_t Offset) {
259 MCSymbol *Label = EmitCFICommon();
260 MCCFIInstruction Instruction =
261 MCCFIInstruction::createDefCfa(Label, Register, Offset);
262 MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo();
263 CurFrame->Instructions.push_back(Instruction);
264 CurFrame->CurrentCfaRegister = static_cast<unsigned>(Register);
267 void MCStreamer::EmitCFIDefCfaOffset(int64_t Offset) {
268 MCSymbol *Label = EmitCFICommon();
269 MCCFIInstruction Instruction =
270 MCCFIInstruction::createDefCfaOffset(Label, Offset);
271 MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo();
272 CurFrame->Instructions.push_back(Instruction);
275 void MCStreamer::EmitCFIAdjustCfaOffset(int64_t Adjustment) {
276 MCSymbol *Label = EmitCFICommon();
277 MCCFIInstruction Instruction =
278 MCCFIInstruction::createAdjustCfaOffset(Label, Adjustment);
279 MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo();
280 CurFrame->Instructions.push_back(Instruction);
283 void MCStreamer::EmitCFIDefCfaRegister(int64_t Register) {
284 MCSymbol *Label = EmitCFICommon();
285 MCCFIInstruction Instruction =
286 MCCFIInstruction::createDefCfaRegister(Label, Register);
287 MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo();
288 CurFrame->Instructions.push_back(Instruction);
289 CurFrame->CurrentCfaRegister = static_cast<unsigned>(Register);
292 void MCStreamer::EmitCFIOffset(int64_t Register, int64_t Offset) {
293 MCSymbol *Label = EmitCFICommon();
294 MCCFIInstruction Instruction =
295 MCCFIInstruction::createOffset(Label, Register, Offset);
296 MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo();
297 CurFrame->Instructions.push_back(Instruction);
300 void MCStreamer::EmitCFIRelOffset(int64_t Register, int64_t Offset) {
301 MCSymbol *Label = EmitCFICommon();
302 MCCFIInstruction Instruction =
303 MCCFIInstruction::createRelOffset(Label, Register, Offset);
304 MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo();
305 CurFrame->Instructions.push_back(Instruction);
308 void MCStreamer::EmitCFIPersonality(const MCSymbol *Sym,
310 EnsureValidDwarfFrame();
311 MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo();
312 CurFrame->Personality = Sym;
313 CurFrame->PersonalityEncoding = Encoding;
316 void MCStreamer::EmitCFILsda(const MCSymbol *Sym, unsigned Encoding) {
317 EnsureValidDwarfFrame();
318 MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo();
319 CurFrame->Lsda = Sym;
320 CurFrame->LsdaEncoding = Encoding;
323 void MCStreamer::EmitCFIRememberState() {
324 MCSymbol *Label = EmitCFICommon();
325 MCCFIInstruction Instruction = MCCFIInstruction::createRememberState(Label);
326 MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo();
327 CurFrame->Instructions.push_back(Instruction);
330 void MCStreamer::EmitCFIRestoreState() {
331 // FIXME: Error if there is no matching cfi_remember_state.
332 MCSymbol *Label = EmitCFICommon();
333 MCCFIInstruction Instruction = MCCFIInstruction::createRestoreState(Label);
334 MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo();
335 CurFrame->Instructions.push_back(Instruction);
338 void MCStreamer::EmitCFISameValue(int64_t Register) {
339 MCSymbol *Label = EmitCFICommon();
340 MCCFIInstruction Instruction =
341 MCCFIInstruction::createSameValue(Label, Register);
342 MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo();
343 CurFrame->Instructions.push_back(Instruction);
346 void MCStreamer::EmitCFIRestore(int64_t Register) {
347 MCSymbol *Label = EmitCFICommon();
348 MCCFIInstruction Instruction =
349 MCCFIInstruction::createRestore(Label, Register);
350 MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo();
351 CurFrame->Instructions.push_back(Instruction);
354 void MCStreamer::EmitCFIEscape(StringRef Values) {
355 MCSymbol *Label = EmitCFICommon();
356 MCCFIInstruction Instruction = MCCFIInstruction::createEscape(Label, Values);
357 MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo();
358 CurFrame->Instructions.push_back(Instruction);
361 void MCStreamer::EmitCFISignalFrame() {
362 EnsureValidDwarfFrame();
363 MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo();
364 CurFrame->IsSignalFrame = true;
367 void MCStreamer::EmitCFIUndefined(int64_t Register) {
368 MCSymbol *Label = EmitCFICommon();
369 MCCFIInstruction Instruction =
370 MCCFIInstruction::createUndefined(Label, Register);
371 MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo();
372 CurFrame->Instructions.push_back(Instruction);
375 void MCStreamer::EmitCFIRegister(int64_t Register1, int64_t Register2) {
376 MCSymbol *Label = EmitCFICommon();
377 MCCFIInstruction Instruction =
378 MCCFIInstruction::createRegister(Label, Register1, Register2);
379 MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo();
380 CurFrame->Instructions.push_back(Instruction);
383 void MCStreamer::EmitCFIWindowSave() {
384 MCSymbol *Label = EmitCFICommon();
385 MCCFIInstruction Instruction =
386 MCCFIInstruction::createWindowSave(Label);
387 MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo();
388 CurFrame->Instructions.push_back(Instruction);
391 void MCStreamer::EnsureValidWinFrameInfo() {
392 const MCAsmInfo *MAI = Context.getAsmInfo();
393 if (!MAI->usesWindowsCFI())
394 report_fatal_error(".seh_* directives are not supported on this target");
395 if (!CurrentWinFrameInfo || CurrentWinFrameInfo->End)
396 report_fatal_error("No open Win64 EH frame function!");
399 void MCStreamer::EmitWinCFIStartProc(const MCSymbol *Symbol) {
400 const MCAsmInfo *MAI = Context.getAsmInfo();
401 if (!MAI->usesWindowsCFI())
402 report_fatal_error(".seh_* directives are not supported on this target");
403 if (CurrentWinFrameInfo && !CurrentWinFrameInfo->End)
404 report_fatal_error("Starting a function before ending the previous one!");
406 MCSymbol *StartProc = getContext().createTempSymbol();
407 EmitLabel(StartProc);
409 WinFrameInfos.push_back(new WinEH::FrameInfo(Symbol, StartProc));
410 CurrentWinFrameInfo = WinFrameInfos.back();
413 void MCStreamer::EmitWinCFIEndProc() {
414 EnsureValidWinFrameInfo();
415 if (CurrentWinFrameInfo->ChainedParent)
416 report_fatal_error("Not all chained regions terminated!");
418 MCSymbol *Label = getContext().createTempSymbol();
420 CurrentWinFrameInfo->End = Label;
423 void MCStreamer::EmitWinCFIStartChained() {
424 EnsureValidWinFrameInfo();
426 MCSymbol *StartProc = getContext().createTempSymbol();
427 EmitLabel(StartProc);
429 WinFrameInfos.push_back(new WinEH::FrameInfo(CurrentWinFrameInfo->Function,
430 StartProc, CurrentWinFrameInfo));
431 CurrentWinFrameInfo = WinFrameInfos.back();
434 void MCStreamer::EmitWinCFIEndChained() {
435 EnsureValidWinFrameInfo();
436 if (!CurrentWinFrameInfo->ChainedParent)
437 report_fatal_error("End of a chained region outside a chained region!");
439 MCSymbol *Label = getContext().createTempSymbol();
442 CurrentWinFrameInfo->End = Label;
443 CurrentWinFrameInfo =
444 const_cast<WinEH::FrameInfo *>(CurrentWinFrameInfo->ChainedParent);
447 void MCStreamer::EmitWinEHHandler(const MCSymbol *Sym, bool Unwind,
449 EnsureValidWinFrameInfo();
450 if (CurrentWinFrameInfo->ChainedParent)
451 report_fatal_error("Chained unwind areas can't have handlers!");
452 CurrentWinFrameInfo->ExceptionHandler = Sym;
453 if (!Except && !Unwind)
454 report_fatal_error("Don't know what kind of handler this is!");
456 CurrentWinFrameInfo->HandlesUnwind = true;
458 CurrentWinFrameInfo->HandlesExceptions = true;
461 void MCStreamer::EmitWinEHHandlerData() {
462 EnsureValidWinFrameInfo();
463 if (CurrentWinFrameInfo->ChainedParent)
464 report_fatal_error("Chained unwind areas can't have handlers!");
467 void MCStreamer::EmitSyntaxDirective() {}
469 void MCStreamer::EmitWinCFIPushReg(unsigned Register) {
470 EnsureValidWinFrameInfo();
472 MCSymbol *Label = getContext().createTempSymbol();
475 WinEH::Instruction Inst = Win64EH::Instruction::PushNonVol(Label, Register);
476 CurrentWinFrameInfo->Instructions.push_back(Inst);
479 void MCStreamer::EmitWinCFISetFrame(unsigned Register, unsigned Offset) {
480 EnsureValidWinFrameInfo();
481 if (CurrentWinFrameInfo->LastFrameInst >= 0)
482 report_fatal_error("Frame register and offset already specified!");
484 report_fatal_error("Misaligned frame pointer offset!");
486 report_fatal_error("Frame offset must be less than or equal to 240!");
488 MCSymbol *Label = getContext().createTempSymbol();
491 WinEH::Instruction Inst =
492 Win64EH::Instruction::SetFPReg(Label, Register, Offset);
493 CurrentWinFrameInfo->LastFrameInst = CurrentWinFrameInfo->Instructions.size();
494 CurrentWinFrameInfo->Instructions.push_back(Inst);
497 void MCStreamer::EmitWinCFIAllocStack(unsigned Size) {
498 EnsureValidWinFrameInfo();
500 report_fatal_error("Allocation size must be non-zero!");
502 report_fatal_error("Misaligned stack allocation!");
504 MCSymbol *Label = getContext().createTempSymbol();
507 WinEH::Instruction Inst = Win64EH::Instruction::Alloc(Label, Size);
508 CurrentWinFrameInfo->Instructions.push_back(Inst);
511 void MCStreamer::EmitWinCFISaveReg(unsigned Register, unsigned Offset) {
512 EnsureValidWinFrameInfo();
514 report_fatal_error("Misaligned saved register offset!");
516 MCSymbol *Label = getContext().createTempSymbol();
519 WinEH::Instruction Inst =
520 Win64EH::Instruction::SaveNonVol(Label, Register, Offset);
521 CurrentWinFrameInfo->Instructions.push_back(Inst);
524 void MCStreamer::EmitWinCFISaveXMM(unsigned Register, unsigned Offset) {
525 EnsureValidWinFrameInfo();
527 report_fatal_error("Misaligned saved vector register offset!");
529 MCSymbol *Label = getContext().createTempSymbol();
532 WinEH::Instruction Inst =
533 Win64EH::Instruction::SaveXMM(Label, Register, Offset);
534 CurrentWinFrameInfo->Instructions.push_back(Inst);
537 void MCStreamer::EmitWinCFIPushFrame(bool Code) {
538 EnsureValidWinFrameInfo();
539 if (CurrentWinFrameInfo->Instructions.size() > 0)
540 report_fatal_error("If present, PushMachFrame must be the first UOP");
542 MCSymbol *Label = getContext().createTempSymbol();
545 WinEH::Instruction Inst = Win64EH::Instruction::PushMachFrame(Label, Code);
546 CurrentWinFrameInfo->Instructions.push_back(Inst);
549 void MCStreamer::EmitWinCFIEndProlog() {
550 EnsureValidWinFrameInfo();
552 MCSymbol *Label = getContext().createTempSymbol();
555 CurrentWinFrameInfo->PrologEnd = Label;
558 void MCStreamer::EmitCOFFSafeSEH(MCSymbol const *Symbol) {
561 void MCStreamer::EmitCOFFSectionIndex(MCSymbol const *Symbol) {
564 void MCStreamer::EmitCOFFSecRel32(MCSymbol const *Symbol) {
567 /// EmitRawText - If this file is backed by an assembly streamer, this dumps
568 /// the specified string in the output .s file. This capability is
569 /// indicated by the hasRawTextSupport() predicate.
570 void MCStreamer::EmitRawTextImpl(StringRef String) {
571 errs() << "EmitRawText called on an MCStreamer that doesn't support it, "
572 " something must not be fully mc'ized\n";
576 void MCStreamer::EmitRawText(const Twine &T) {
577 SmallString<128> Str;
578 EmitRawTextImpl(T.toStringRef(Str));
581 void MCStreamer::EmitWindowsUnwindTables() {
584 void MCStreamer::Finish() {
585 if (!DwarfFrameInfos.empty() && !DwarfFrameInfos.back().End)
586 report_fatal_error("Unfinished frame!");
588 MCTargetStreamer *TS = getTargetStreamer();
595 void MCStreamer::EmitAssignment(MCSymbol *Symbol, const MCExpr *Value) {
596 visitUsedExpr(*Value);
597 Symbol->setVariableValue(Value);
599 MCTargetStreamer *TS = getTargetStreamer();
601 TS->emitAssignment(Symbol, Value);
604 void MCTargetStreamer::prettyPrintAsm(MCInstPrinter &InstPrinter, raw_ostream &OS,
605 const MCInst &Inst, const MCSubtargetInfo &STI) {
606 InstPrinter.printInst(&Inst, OS, "", STI);
609 void MCStreamer::visitUsedSymbol(const MCSymbol &Sym) {
612 void MCStreamer::visitUsedExpr(const MCExpr &Expr) {
613 switch (Expr.getKind()) {
615 cast<MCTargetExpr>(Expr).visitUsedExpr(*this);
618 case MCExpr::Constant:
621 case MCExpr::Binary: {
622 const MCBinaryExpr &BE = cast<MCBinaryExpr>(Expr);
623 visitUsedExpr(*BE.getLHS());
624 visitUsedExpr(*BE.getRHS());
628 case MCExpr::SymbolRef:
629 visitUsedSymbol(cast<MCSymbolRefExpr>(Expr).getSymbol());
633 visitUsedExpr(*cast<MCUnaryExpr>(Expr).getSubExpr());
638 void MCStreamer::EmitInstruction(const MCInst &Inst,
639 const MCSubtargetInfo &STI) {
641 for (unsigned i = Inst.getNumOperands(); i--;)
642 if (Inst.getOperand(i).isExpr())
643 visitUsedExpr(*Inst.getOperand(i).getExpr());
646 void MCStreamer::emitAbsoluteSymbolDiff(const MCSymbol *Hi, const MCSymbol *Lo,
648 // Get the Hi-Lo expression.
650 MCBinaryExpr::createSub(MCSymbolRefExpr::create(Hi, Context),
651 MCSymbolRefExpr::create(Lo, Context), Context);
653 const MCAsmInfo *MAI = Context.getAsmInfo();
654 if (!MAI->doesSetDirectiveSuppressesReloc()) {
655 EmitValue(Diff, Size);
659 // Otherwise, emit with .set (aka assignment).
660 MCSymbol *SetLabel = Context.createTempSymbol("set", true);
661 EmitAssignment(SetLabel, Diff);
662 EmitSymbolValue(SetLabel, Size);
665 void MCStreamer::EmitAssemblerFlag(MCAssemblerFlag Flag) {}
666 void MCStreamer::EmitThumbFunc(MCSymbol *Func) {}
667 void MCStreamer::EmitSymbolDesc(MCSymbol *Symbol, unsigned DescValue) {}
668 void MCStreamer::BeginCOFFSymbolDef(const MCSymbol *Symbol) {}
669 void MCStreamer::EndCOFFSymbolDef() {}
670 void MCStreamer::EmitFileDirective(StringRef Filename) {}
671 void MCStreamer::EmitCOFFSymbolStorageClass(int StorageClass) {}
672 void MCStreamer::EmitCOFFSymbolType(int Type) {}
673 void MCStreamer::emitELFSize(MCSymbolELF *Symbol, const MCExpr *Value) {}
674 void MCStreamer::EmitLocalCommonSymbol(MCSymbol *Symbol, uint64_t Size,
675 unsigned ByteAlignment) {}
676 void MCStreamer::EmitTBSSSymbol(MCSection *Section, MCSymbol *Symbol,
677 uint64_t Size, unsigned ByteAlignment) {}
678 void MCStreamer::ChangeSection(MCSection *, const MCExpr *) {}
679 void MCStreamer::EmitWeakReference(MCSymbol *Alias, const MCSymbol *Symbol) {}
680 void MCStreamer::EmitBytes(StringRef Data) {}
681 void MCStreamer::EmitValueImpl(const MCExpr *Value, unsigned Size, SMLoc Loc) {
682 visitUsedExpr(*Value);
684 void MCStreamer::EmitULEB128Value(const MCExpr *Value) {}
685 void MCStreamer::EmitSLEB128Value(const MCExpr *Value) {}
686 void MCStreamer::EmitValueToAlignment(unsigned ByteAlignment, int64_t Value,
688 unsigned MaxBytesToEmit) {}
689 void MCStreamer::EmitCodeAlignment(unsigned ByteAlignment,
690 unsigned MaxBytesToEmit) {}
691 bool MCStreamer::EmitValueToOffset(const MCExpr *Offset, unsigned char Value) {
694 void MCStreamer::EmitBundleAlignMode(unsigned AlignPow2) {}
695 void MCStreamer::EmitBundleLock(bool AlignToEnd) {}
696 void MCStreamer::FinishImpl() {}
697 void MCStreamer::EmitBundleUnlock() {}
699 void MCStreamer::SwitchSection(MCSection *Section, const MCExpr *Subsection) {
700 assert(Section && "Cannot switch to a null section!");
701 MCSectionSubPair curSection = SectionStack.back().first;
702 SectionStack.back().second = curSection;
703 if (MCSectionSubPair(Section, Subsection) != curSection) {
704 ChangeSection(Section, Subsection);
705 SectionStack.back().first = MCSectionSubPair(Section, Subsection);
706 assert(!Section->hasEnded() && "Section already ended");
707 MCSymbol *Sym = Section->getBeginSymbol();
708 if (Sym && !Sym->isInSection())
713 MCSymbol *MCStreamer::endSection(MCSection *Section) {
714 // TODO: keep track of the last subsection so that this symbol appears in the
716 MCSymbol *Sym = Section->getEndSymbol(Context);
717 if (Sym->isInSection())
720 SwitchSection(Section);