1//===- lib/MC/MCStreamer.cpp - Streaming Machine Code Output --------------===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9
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/MCObjectFileInfo.h"
18#include "llvm/MC/MCObjectWriter.h"
19#include "llvm/MC/MCSymbol.h"
20#include "llvm/Support/ErrorHandling.h"
21#include "llvm/Support/LEB128.h"
22#include "llvm/Support/raw_ostream.h"
23#include <cstdlib>
24using namespace llvm;
25
26// Pin the vtables to this file.
27MCTargetStreamer::~MCTargetStreamer() {}
28
29MCTargetStreamer::MCTargetStreamer(MCStreamer &S) : Streamer(S) {
30  S.setTargetStreamer(this);
31}
32
33void MCTargetStreamer::emitLabel(MCSymbol *Symbol) {}
34
35void MCTargetStreamer::finish() {}
36
37void MCTargetStreamer::emitAssignment(MCSymbol *Symbol, const MCExpr *Value) {}
38
39MCStreamer::MCStreamer(MCContext &Ctx)
40    : Context(Ctx), CurrentW64UnwindInfo(nullptr) {
41  SectionStack.push_back(std::pair<MCSectionSubPair, MCSectionSubPair>());
42}
43
44MCStreamer::~MCStreamer() {
45  for (unsigned i = 0; i < getNumW64UnwindInfos(); ++i)
46    delete W64UnwindInfos[i];
47}
48
49void MCStreamer::reset() {
50  for (unsigned i = 0; i < getNumW64UnwindInfos(); ++i)
51    delete W64UnwindInfos[i];
52  W64UnwindInfos.clear();
53  CurrentW64UnwindInfo = nullptr;
54  SectionStack.clear();
55  SectionStack.push_back(std::pair<MCSectionSubPair, MCSectionSubPair>());
56}
57
58const MCExpr *MCStreamer::BuildSymbolDiff(MCContext &Context,
59                                          const MCSymbol *A,
60                                          const MCSymbol *B) {
61  MCSymbolRefExpr::VariantKind Variant = MCSymbolRefExpr::VK_None;
62  const MCExpr *ARef =
63    MCSymbolRefExpr::Create(A, Variant, Context);
64  const MCExpr *BRef =
65    MCSymbolRefExpr::Create(B, Variant, Context);
66  const MCExpr *AddrDelta =
67    MCBinaryExpr::Create(MCBinaryExpr::Sub, ARef, BRef, Context);
68  return AddrDelta;
69}
70
71const MCExpr *MCStreamer::ForceExpAbs(const MCExpr* Expr) {
72  assert(!isa<MCSymbolRefExpr>(Expr));
73  if (Context.getAsmInfo()->hasAggressiveSymbolFolding())
74    return Expr;
75
76  MCSymbol *ABS = Context.CreateTempSymbol();
77  EmitAssignment(ABS, Expr);
78  return MCSymbolRefExpr::Create(ABS, Context);
79}
80
81raw_ostream &MCStreamer::GetCommentOS() {
82  // By default, discard comments.
83  return nulls();
84}
85
86void MCStreamer::emitRawComment(const Twine &T, bool TabPrefix) {}
87
88void MCStreamer::generateCompactUnwindEncodings(MCAsmBackend *MAB) {
89  for (std::vector<MCDwarfFrameInfo>::iterator I = FrameInfos.begin(),
90         E = FrameInfos.end(); I != E; ++I)
91    I->CompactUnwindEncoding =
92      (MAB ? MAB->generateCompactUnwindEncoding(I->Instructions) : 0);
93}
94
95void MCStreamer::EmitDwarfSetLineAddr(int64_t LineDelta,
96                                      const MCSymbol *Label, int PointerSize) {
97  // emit the sequence to set the address
98  EmitIntValue(dwarf::DW_LNS_extended_op, 1);
99  EmitULEB128IntValue(PointerSize + 1);
100  EmitIntValue(dwarf::DW_LNE_set_address, 1);
101  EmitSymbolValue(Label, PointerSize);
102
103  // emit the sequence for the LineDelta (from 1) and a zero address delta.
104  MCDwarfLineAddr::Emit(this, LineDelta, 0);
105}
106
107/// EmitIntValue - Special case of EmitValue that avoids the client having to
108/// pass in a MCExpr for constant integers.
109void MCStreamer::EmitIntValue(uint64_t Value, unsigned Size) {
110  assert(Size <= 8 && "Invalid size");
111  assert((isUIntN(8 * Size, Value) || isIntN(8 * Size, Value)) &&
112         "Invalid size");
113  char buf[8];
114  const bool isLittleEndian = Context.getAsmInfo()->isLittleEndian();
115  for (unsigned i = 0; i != Size; ++i) {
116    unsigned index = isLittleEndian ? i : (Size - i - 1);
117    buf[i] = uint8_t(Value >> (index * 8));
118  }
119  EmitBytes(StringRef(buf, Size));
120}
121
122/// EmitULEB128Value - Special case of EmitULEB128Value that avoids the
123/// client having to pass in a MCExpr for constant integers.
124void MCStreamer::EmitULEB128IntValue(uint64_t Value, unsigned Padding) {
125  SmallString<128> Tmp;
126  raw_svector_ostream OSE(Tmp);
127  encodeULEB128(Value, OSE, Padding);
128  EmitBytes(OSE.str());
129}
130
131/// EmitSLEB128Value - Special case of EmitSLEB128Value that avoids the
132/// client having to pass in a MCExpr for constant integers.
133void MCStreamer::EmitSLEB128IntValue(int64_t Value) {
134  SmallString<128> Tmp;
135  raw_svector_ostream OSE(Tmp);
136  encodeSLEB128(Value, OSE);
137  EmitBytes(OSE.str());
138}
139
140void MCStreamer::EmitAbsValue(const MCExpr *Value, unsigned Size) {
141  const MCExpr *ABS = ForceExpAbs(Value);
142  EmitValue(ABS, Size);
143}
144
145
146void MCStreamer::EmitValue(const MCExpr *Value, unsigned Size,
147                           const SMLoc &Loc) {
148  EmitValueImpl(Value, Size, Loc);
149}
150
151void MCStreamer::EmitSymbolValue(const MCSymbol *Sym, unsigned Size) {
152  EmitValueImpl(MCSymbolRefExpr::Create(Sym, getContext()), Size);
153}
154
155void MCStreamer::EmitGPRel64Value(const MCExpr *Value) {
156  report_fatal_error("unsupported directive in streamer");
157}
158
159void MCStreamer::EmitGPRel32Value(const MCExpr *Value) {
160  report_fatal_error("unsupported directive in streamer");
161}
162
163/// EmitFill - Emit NumBytes bytes worth of the value specified by
164/// FillValue.  This implements directives such as '.space'.
165void MCStreamer::EmitFill(uint64_t NumBytes, uint8_t FillValue) {
166  const MCExpr *E = MCConstantExpr::Create(FillValue, getContext());
167  for (uint64_t i = 0, e = NumBytes; i != e; ++i)
168    EmitValue(E, 1);
169}
170
171/// The implementation in this class just redirects to EmitFill.
172void MCStreamer::EmitZeros(uint64_t NumBytes) {
173  EmitFill(NumBytes, 0);
174}
175
176unsigned MCStreamer::EmitDwarfFileDirective(unsigned FileNo,
177                                            StringRef Directory,
178                                            StringRef Filename, unsigned CUID) {
179  return getContext().GetDwarfFile(Directory, Filename, FileNo, CUID);
180}
181
182void MCStreamer::EmitDwarfLocDirective(unsigned FileNo, unsigned Line,
183                                       unsigned Column, unsigned Flags,
184                                       unsigned Isa,
185                                       unsigned Discriminator,
186                                       StringRef FileName) {
187  getContext().setCurrentDwarfLoc(FileNo, Line, Column, Flags, Isa,
188                                  Discriminator);
189}
190
191MCSymbol *MCStreamer::getDwarfLineTableSymbol(unsigned CUID) {
192  MCDwarfLineTable &Table = getContext().getMCDwarfLineTable(CUID);
193  if (!Table.getLabel()) {
194    StringRef Prefix = Context.getAsmInfo()->getPrivateGlobalPrefix();
195    Table.setLabel(
196        Context.GetOrCreateSymbol(Prefix + "line_table_start" + Twine(CUID)));
197  }
198  return Table.getLabel();
199}
200
201MCDwarfFrameInfo *MCStreamer::getCurrentFrameInfo() {
202  if (FrameInfos.empty())
203    return nullptr;
204  return &FrameInfos.back();
205}
206
207void MCStreamer::EnsureValidFrame() {
208  MCDwarfFrameInfo *CurFrame = getCurrentFrameInfo();
209  if (!CurFrame || CurFrame->End)
210    report_fatal_error("No open frame");
211}
212
213void MCStreamer::EmitEHSymAttributes(const MCSymbol *Symbol,
214                                     MCSymbol *EHSymbol) {
215}
216
217void MCStreamer::InitSections() {
218  SwitchSection(getContext().getObjectFileInfo()->getTextSection());
219}
220
221void MCStreamer::AssignSection(MCSymbol *Symbol, const MCSection *Section) {
222  if (Section)
223    Symbol->setSection(*Section);
224  else
225    Symbol->setUndefined();
226
227  // As we emit symbols into a section, track the order so that they can
228  // be sorted upon later. Zero is reserved to mean 'unemitted'.
229  SymbolOrdering[Symbol] = 1 + SymbolOrdering.size();
230}
231
232void MCStreamer::EmitLabel(MCSymbol *Symbol) {
233  assert(!Symbol->isVariable() && "Cannot emit a variable symbol!");
234  assert(getCurrentSection().first && "Cannot emit before setting section!");
235  AssignSection(Symbol, getCurrentSection().first);
236
237  MCTargetStreamer *TS = getTargetStreamer();
238  if (TS)
239    TS->emitLabel(Symbol);
240}
241
242void MCStreamer::EmitCompactUnwindEncoding(uint32_t CompactUnwindEncoding) {
243  EnsureValidFrame();
244  MCDwarfFrameInfo *CurFrame = getCurrentFrameInfo();
245  CurFrame->CompactUnwindEncoding = CompactUnwindEncoding;
246}
247
248void MCStreamer::EmitCFISections(bool EH, bool Debug) {
249  assert(EH || Debug);
250}
251
252void MCStreamer::EmitCFIStartProc(bool IsSimple) {
253  MCDwarfFrameInfo *CurFrame = getCurrentFrameInfo();
254  if (CurFrame && !CurFrame->End)
255    report_fatal_error("Starting a frame before finishing the previous one!");
256
257  MCDwarfFrameInfo Frame;
258  Frame.IsSimple = IsSimple;
259  EmitCFIStartProcImpl(Frame);
260
261  FrameInfos.push_back(Frame);
262}
263
264void MCStreamer::EmitCFIStartProcImpl(MCDwarfFrameInfo &Frame) {
265}
266
267void MCStreamer::EmitCFIEndProc() {
268  EnsureValidFrame();
269  MCDwarfFrameInfo *CurFrame = getCurrentFrameInfo();
270  EmitCFIEndProcImpl(*CurFrame);
271}
272
273void MCStreamer::EmitCFIEndProcImpl(MCDwarfFrameInfo &Frame) {
274  // Put a dummy non-null value in Frame.End to mark that this frame has been
275  // closed.
276  Frame.End = (MCSymbol *) 1;
277}
278
279MCSymbol *MCStreamer::EmitCFICommon() {
280  EnsureValidFrame();
281  MCSymbol *Label = getContext().CreateTempSymbol();
282  EmitLabel(Label);
283  return Label;
284}
285
286void MCStreamer::EmitCFIDefCfa(int64_t Register, int64_t Offset) {
287  MCSymbol *Label = EmitCFICommon();
288  MCCFIInstruction Instruction =
289    MCCFIInstruction::createDefCfa(Label, Register, Offset);
290  MCDwarfFrameInfo *CurFrame = getCurrentFrameInfo();
291  CurFrame->Instructions.push_back(Instruction);
292}
293
294void MCStreamer::EmitCFIDefCfaOffset(int64_t Offset) {
295  MCSymbol *Label = EmitCFICommon();
296  MCCFIInstruction Instruction =
297    MCCFIInstruction::createDefCfaOffset(Label, Offset);
298  MCDwarfFrameInfo *CurFrame = getCurrentFrameInfo();
299  CurFrame->Instructions.push_back(Instruction);
300}
301
302void MCStreamer::EmitCFIAdjustCfaOffset(int64_t Adjustment) {
303  MCSymbol *Label = EmitCFICommon();
304  MCCFIInstruction Instruction =
305    MCCFIInstruction::createAdjustCfaOffset(Label, Adjustment);
306  MCDwarfFrameInfo *CurFrame = getCurrentFrameInfo();
307  CurFrame->Instructions.push_back(Instruction);
308}
309
310void MCStreamer::EmitCFIDefCfaRegister(int64_t Register) {
311  MCSymbol *Label = EmitCFICommon();
312  MCCFIInstruction Instruction =
313    MCCFIInstruction::createDefCfaRegister(Label, Register);
314  MCDwarfFrameInfo *CurFrame = getCurrentFrameInfo();
315  CurFrame->Instructions.push_back(Instruction);
316}
317
318void MCStreamer::EmitCFIOffset(int64_t Register, int64_t Offset) {
319  MCSymbol *Label = EmitCFICommon();
320  MCCFIInstruction Instruction =
321    MCCFIInstruction::createOffset(Label, Register, Offset);
322  MCDwarfFrameInfo *CurFrame = getCurrentFrameInfo();
323  CurFrame->Instructions.push_back(Instruction);
324}
325
326void MCStreamer::EmitCFIRelOffset(int64_t Register, int64_t Offset) {
327  MCSymbol *Label = EmitCFICommon();
328  MCCFIInstruction Instruction =
329    MCCFIInstruction::createRelOffset(Label, Register, Offset);
330  MCDwarfFrameInfo *CurFrame = getCurrentFrameInfo();
331  CurFrame->Instructions.push_back(Instruction);
332}
333
334void MCStreamer::EmitCFIPersonality(const MCSymbol *Sym,
335                                    unsigned Encoding) {
336  EnsureValidFrame();
337  MCDwarfFrameInfo *CurFrame = getCurrentFrameInfo();
338  CurFrame->Personality = Sym;
339  CurFrame->PersonalityEncoding = Encoding;
340}
341
342void MCStreamer::EmitCFILsda(const MCSymbol *Sym, unsigned Encoding) {
343  EnsureValidFrame();
344  MCDwarfFrameInfo *CurFrame = getCurrentFrameInfo();
345  CurFrame->Lsda = Sym;
346  CurFrame->LsdaEncoding = Encoding;
347}
348
349void MCStreamer::EmitCFIRememberState() {
350  MCSymbol *Label = EmitCFICommon();
351  MCCFIInstruction Instruction = MCCFIInstruction::createRememberState(Label);
352  MCDwarfFrameInfo *CurFrame = getCurrentFrameInfo();
353  CurFrame->Instructions.push_back(Instruction);
354}
355
356void MCStreamer::EmitCFIRestoreState() {
357  // FIXME: Error if there is no matching cfi_remember_state.
358  MCSymbol *Label = EmitCFICommon();
359  MCCFIInstruction Instruction = MCCFIInstruction::createRestoreState(Label);
360  MCDwarfFrameInfo *CurFrame = getCurrentFrameInfo();
361  CurFrame->Instructions.push_back(Instruction);
362}
363
364void MCStreamer::EmitCFISameValue(int64_t Register) {
365  MCSymbol *Label = EmitCFICommon();
366  MCCFIInstruction Instruction =
367    MCCFIInstruction::createSameValue(Label, Register);
368  MCDwarfFrameInfo *CurFrame = getCurrentFrameInfo();
369  CurFrame->Instructions.push_back(Instruction);
370}
371
372void MCStreamer::EmitCFIRestore(int64_t Register) {
373  MCSymbol *Label = EmitCFICommon();
374  MCCFIInstruction Instruction =
375    MCCFIInstruction::createRestore(Label, Register);
376  MCDwarfFrameInfo *CurFrame = getCurrentFrameInfo();
377  CurFrame->Instructions.push_back(Instruction);
378}
379
380void MCStreamer::EmitCFIEscape(StringRef Values) {
381  MCSymbol *Label = EmitCFICommon();
382  MCCFIInstruction Instruction = MCCFIInstruction::createEscape(Label, Values);
383  MCDwarfFrameInfo *CurFrame = getCurrentFrameInfo();
384  CurFrame->Instructions.push_back(Instruction);
385}
386
387void MCStreamer::EmitCFISignalFrame() {
388  EnsureValidFrame();
389  MCDwarfFrameInfo *CurFrame = getCurrentFrameInfo();
390  CurFrame->IsSignalFrame = true;
391}
392
393void MCStreamer::EmitCFIUndefined(int64_t Register) {
394  MCSymbol *Label = EmitCFICommon();
395  MCCFIInstruction Instruction =
396    MCCFIInstruction::createUndefined(Label, Register);
397  MCDwarfFrameInfo *CurFrame = getCurrentFrameInfo();
398  CurFrame->Instructions.push_back(Instruction);
399}
400
401void MCStreamer::EmitCFIRegister(int64_t Register1, int64_t Register2) {
402  MCSymbol *Label = EmitCFICommon();
403  MCCFIInstruction Instruction =
404    MCCFIInstruction::createRegister(Label, Register1, Register2);
405  MCDwarfFrameInfo *CurFrame = getCurrentFrameInfo();
406  CurFrame->Instructions.push_back(Instruction);
407}
408
409void MCStreamer::EmitCFIWindowSave() {
410  MCSymbol *Label = EmitCFICommon();
411  MCCFIInstruction Instruction =
412    MCCFIInstruction::createWindowSave(Label);
413  MCDwarfFrameInfo *CurFrame = getCurrentFrameInfo();
414  CurFrame->Instructions.push_back(Instruction);
415}
416
417void MCStreamer::setCurrentW64UnwindInfo(MCWin64EHUnwindInfo *Frame) {
418  W64UnwindInfos.push_back(Frame);
419  CurrentW64UnwindInfo = W64UnwindInfos.back();
420}
421
422void MCStreamer::EnsureValidW64UnwindInfo() {
423  MCWin64EHUnwindInfo *CurFrame = CurrentW64UnwindInfo;
424  if (!CurFrame || CurFrame->End)
425    report_fatal_error("No open Win64 EH frame function!");
426}
427
428void MCStreamer::EmitWinCFIStartProc(const MCSymbol *Symbol) {
429  MCWin64EHUnwindInfo *CurFrame = CurrentW64UnwindInfo;
430  if (CurFrame && !CurFrame->End)
431    report_fatal_error("Starting a function before ending the previous one!");
432  MCWin64EHUnwindInfo *Frame = new MCWin64EHUnwindInfo;
433  Frame->Begin = getContext().CreateTempSymbol();
434  Frame->Function = Symbol;
435  EmitLabel(Frame->Begin);
436  setCurrentW64UnwindInfo(Frame);
437}
438
439void MCStreamer::EmitWinCFIEndProc() {
440  EnsureValidW64UnwindInfo();
441  MCWin64EHUnwindInfo *CurFrame = CurrentW64UnwindInfo;
442  if (CurFrame->ChainedParent)
443    report_fatal_error("Not all chained regions terminated!");
444  CurFrame->End = getContext().CreateTempSymbol();
445  EmitLabel(CurFrame->End);
446}
447
448void MCStreamer::EmitWinCFIStartChained() {
449  EnsureValidW64UnwindInfo();
450  MCWin64EHUnwindInfo *Frame = new MCWin64EHUnwindInfo;
451  MCWin64EHUnwindInfo *CurFrame = CurrentW64UnwindInfo;
452  Frame->Begin = getContext().CreateTempSymbol();
453  Frame->Function = CurFrame->Function;
454  Frame->ChainedParent = CurFrame;
455  EmitLabel(Frame->Begin);
456  setCurrentW64UnwindInfo(Frame);
457}
458
459void MCStreamer::EmitWinCFIEndChained() {
460  EnsureValidW64UnwindInfo();
461  MCWin64EHUnwindInfo *CurFrame = CurrentW64UnwindInfo;
462  if (!CurFrame->ChainedParent)
463    report_fatal_error("End of a chained region outside a chained region!");
464  CurFrame->End = getContext().CreateTempSymbol();
465  EmitLabel(CurFrame->End);
466  CurrentW64UnwindInfo = CurFrame->ChainedParent;
467}
468
469void MCStreamer::EmitWinEHHandler(const MCSymbol *Sym, bool Unwind,
470                                  bool Except) {
471  EnsureValidW64UnwindInfo();
472  MCWin64EHUnwindInfo *CurFrame = CurrentW64UnwindInfo;
473  if (CurFrame->ChainedParent)
474    report_fatal_error("Chained unwind areas can't have handlers!");
475  CurFrame->ExceptionHandler = Sym;
476  if (!Except && !Unwind)
477    report_fatal_error("Don't know what kind of handler this is!");
478  if (Unwind)
479    CurFrame->HandlesUnwind = true;
480  if (Except)
481    CurFrame->HandlesExceptions = true;
482}
483
484void MCStreamer::EmitWinEHHandlerData() {
485  EnsureValidW64UnwindInfo();
486  MCWin64EHUnwindInfo *CurFrame = CurrentW64UnwindInfo;
487  if (CurFrame->ChainedParent)
488    report_fatal_error("Chained unwind areas can't have handlers!");
489}
490
491void MCStreamer::EmitWinCFIPushReg(unsigned Register) {
492  EnsureValidW64UnwindInfo();
493  MCWin64EHUnwindInfo *CurFrame = CurrentW64UnwindInfo;
494  MCSymbol *Label = getContext().CreateTempSymbol();
495  MCWin64EHInstruction Inst(Win64EH::UOP_PushNonVol, Label, Register);
496  EmitLabel(Label);
497  CurFrame->Instructions.push_back(Inst);
498}
499
500void MCStreamer::EmitWinCFISetFrame(unsigned Register, unsigned Offset) {
501  EnsureValidW64UnwindInfo();
502  MCWin64EHUnwindInfo *CurFrame = CurrentW64UnwindInfo;
503  if (CurFrame->LastFrameInst >= 0)
504    report_fatal_error("Frame register and offset already specified!");
505  if (Offset & 0x0F)
506    report_fatal_error("Misaligned frame pointer offset!");
507  if (Offset > 240)
508    report_fatal_error("Frame offset must be less than or equal to 240!");
509  MCSymbol *Label = getContext().CreateTempSymbol();
510  MCWin64EHInstruction Inst(Win64EH::UOP_SetFPReg, Label, Register, Offset);
511  EmitLabel(Label);
512  CurFrame->LastFrameInst = CurFrame->Instructions.size();
513  CurFrame->Instructions.push_back(Inst);
514}
515
516void MCStreamer::EmitWinCFIAllocStack(unsigned Size) {
517  EnsureValidW64UnwindInfo();
518  if (Size == 0)
519    report_fatal_error("Allocation size must be non-zero!");
520  if (Size & 7)
521    report_fatal_error("Misaligned stack allocation!");
522  MCWin64EHUnwindInfo *CurFrame = CurrentW64UnwindInfo;
523  MCSymbol *Label = getContext().CreateTempSymbol();
524  MCWin64EHInstruction Inst(Label, Size);
525  EmitLabel(Label);
526  CurFrame->Instructions.push_back(Inst);
527}
528
529void MCStreamer::EmitWinCFISaveReg(unsigned Register, unsigned Offset) {
530  EnsureValidW64UnwindInfo();
531  if (Offset & 7)
532    report_fatal_error("Misaligned saved register offset!");
533  MCWin64EHUnwindInfo *CurFrame = CurrentW64UnwindInfo;
534  MCSymbol *Label = getContext().CreateTempSymbol();
535  MCWin64EHInstruction Inst(
536     Offset > 512*1024-8 ? Win64EH::UOP_SaveNonVolBig : Win64EH::UOP_SaveNonVol,
537                            Label, Register, Offset);
538  EmitLabel(Label);
539  CurFrame->Instructions.push_back(Inst);
540}
541
542void MCStreamer::EmitWinCFISaveXMM(unsigned Register, unsigned Offset) {
543  EnsureValidW64UnwindInfo();
544  if (Offset & 0x0F)
545    report_fatal_error("Misaligned saved vector register offset!");
546  MCWin64EHUnwindInfo *CurFrame = CurrentW64UnwindInfo;
547  MCSymbol *Label = getContext().CreateTempSymbol();
548  MCWin64EHInstruction Inst(
549    Offset > 512*1024-16 ? Win64EH::UOP_SaveXMM128Big : Win64EH::UOP_SaveXMM128,
550                            Label, Register, Offset);
551  EmitLabel(Label);
552  CurFrame->Instructions.push_back(Inst);
553}
554
555void MCStreamer::EmitWinCFIPushFrame(bool Code) {
556  EnsureValidW64UnwindInfo();
557  MCWin64EHUnwindInfo *CurFrame = CurrentW64UnwindInfo;
558  if (CurFrame->Instructions.size() > 0)
559    report_fatal_error("If present, PushMachFrame must be the first UOP");
560  MCSymbol *Label = getContext().CreateTempSymbol();
561  MCWin64EHInstruction Inst(Win64EH::UOP_PushMachFrame, Label, Code);
562  EmitLabel(Label);
563  CurFrame->Instructions.push_back(Inst);
564}
565
566void MCStreamer::EmitWinCFIEndProlog() {
567  EnsureValidW64UnwindInfo();
568  MCWin64EHUnwindInfo *CurFrame = CurrentW64UnwindInfo;
569  CurFrame->PrologEnd = getContext().CreateTempSymbol();
570  EmitLabel(CurFrame->PrologEnd);
571}
572
573void MCStreamer::EmitCOFFSectionIndex(MCSymbol const *Symbol) {
574}
575
576void MCStreamer::EmitCOFFSecRel32(MCSymbol const *Symbol) {
577}
578
579/// EmitRawText - If this file is backed by an assembly streamer, this dumps
580/// the specified string in the output .s file.  This capability is
581/// indicated by the hasRawTextSupport() predicate.
582void MCStreamer::EmitRawTextImpl(StringRef String) {
583  errs() << "EmitRawText called on an MCStreamer that doesn't support it, "
584  " something must not be fully mc'ized\n";
585  abort();
586}
587
588void MCStreamer::EmitRawText(const Twine &T) {
589  SmallString<128> Str;
590  EmitRawTextImpl(T.toStringRef(Str));
591}
592
593void MCStreamer::EmitW64Tables() {
594  if (!getNumW64UnwindInfos())
595    return;
596
597  MCWin64EHUnwindEmitter::Emit(*this);
598}
599
600void MCStreamer::Finish() {
601  if (!FrameInfos.empty() && !FrameInfos.back().End)
602    report_fatal_error("Unfinished frame!");
603
604  MCTargetStreamer *TS = getTargetStreamer();
605  if (TS)
606    TS->finish();
607
608  FinishImpl();
609}
610
611void MCStreamer::EmitAssignment(MCSymbol *Symbol, const MCExpr *Value) {
612  visitUsedExpr(*Value);
613  Symbol->setVariableValue(Value);
614
615  MCTargetStreamer *TS = getTargetStreamer();
616  if (TS)
617    TS->emitAssignment(Symbol, Value);
618}
619
620void MCStreamer::visitUsedSymbol(const MCSymbol &Sym) {
621}
622
623void MCStreamer::visitUsedExpr(const MCExpr &Expr) {
624  switch (Expr.getKind()) {
625  case MCExpr::Target:
626    cast<MCTargetExpr>(Expr).visitUsedExpr(*this);
627    break;
628
629  case MCExpr::Constant:
630    break;
631
632  case MCExpr::Binary: {
633    const MCBinaryExpr &BE = cast<MCBinaryExpr>(Expr);
634    visitUsedExpr(*BE.getLHS());
635    visitUsedExpr(*BE.getRHS());
636    break;
637  }
638
639  case MCExpr::SymbolRef:
640    visitUsedSymbol(cast<MCSymbolRefExpr>(Expr).getSymbol());
641    break;
642
643  case MCExpr::Unary:
644    visitUsedExpr(*cast<MCUnaryExpr>(Expr).getSubExpr());
645    break;
646  }
647}
648
649void MCStreamer::EmitInstruction(const MCInst &Inst,
650                                 const MCSubtargetInfo &STI) {
651  // Scan for values.
652  for (unsigned i = Inst.getNumOperands(); i--;)
653    if (Inst.getOperand(i).isExpr())
654      visitUsedExpr(*Inst.getOperand(i).getExpr());
655}
656
657void MCStreamer::EmitAssemblerFlag(MCAssemblerFlag Flag) {}
658void MCStreamer::EmitThumbFunc(MCSymbol *Func) {}
659void MCStreamer::EmitSymbolDesc(MCSymbol *Symbol, unsigned DescValue) {}
660void MCStreamer::BeginCOFFSymbolDef(const MCSymbol *Symbol) {}
661void MCStreamer::EndCOFFSymbolDef() {}
662void MCStreamer::EmitFileDirective(StringRef Filename) {}
663void MCStreamer::EmitCOFFSymbolStorageClass(int StorageClass) {}
664void MCStreamer::EmitCOFFSymbolType(int Type) {}
665void MCStreamer::EmitELFSize(MCSymbol *Symbol, const MCExpr *Value) {}
666void MCStreamer::EmitLocalCommonSymbol(MCSymbol *Symbol, uint64_t Size,
667                                       unsigned ByteAlignment) {}
668void MCStreamer::EmitTBSSSymbol(const MCSection *Section, MCSymbol *Symbol,
669                                uint64_t Size, unsigned ByteAlignment) {}
670void MCStreamer::ChangeSection(const MCSection *, const MCExpr *) {}
671void MCStreamer::EmitWeakReference(MCSymbol *Alias, const MCSymbol *Symbol) {}
672void MCStreamer::EmitBytes(StringRef Data) {}
673void MCStreamer::EmitValueImpl(const MCExpr *Value, unsigned Size,
674                               const SMLoc &Loc) {
675  visitUsedExpr(*Value);
676}
677void MCStreamer::EmitULEB128Value(const MCExpr *Value) {}
678void MCStreamer::EmitSLEB128Value(const MCExpr *Value) {}
679void MCStreamer::EmitValueToAlignment(unsigned ByteAlignment, int64_t Value,
680                                      unsigned ValueSize,
681                                      unsigned MaxBytesToEmit) {}
682void MCStreamer::EmitCodeAlignment(unsigned ByteAlignment,
683                                   unsigned MaxBytesToEmit) {}
684bool MCStreamer::EmitValueToOffset(const MCExpr *Offset, unsigned char Value) {
685  return false;
686}
687void MCStreamer::EmitBundleAlignMode(unsigned AlignPow2) {}
688void MCStreamer::EmitBundleLock(bool AlignToEnd) {}
689void MCStreamer::FinishImpl() {}
690void MCStreamer::EmitBundleUnlock() {}
691