llvm/lib/MC/MCStreamer.cpp

   1 //===- lib/MC/MCStreamer.cpp - Streaming Machine Code Output --------------===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8
   9 #include "llvm/MC/MCStreamer.h"
  10 #include "llvm/ADT/Optional.h"
  11 #include "llvm/ADT/SmallString.h"
  12 #include "llvm/ADT/StringRef.h"
  13 #include "llvm/ADT/Twine.h"
  14 #include "llvm/BinaryFormat/COFF.h"
  15 #include "llvm/DebugInfo/CodeView/SymbolRecord.h"
  16 #include "llvm/MC/MCAsmBackend.h"
  17 #include "llvm/MC/MCAsmInfo.h"
  18 #include "llvm/MC/MCCodeView.h"
  19 #include "llvm/MC/MCContext.h"
  20 #include "llvm/MC/MCDwarf.h"
  21 #include "llvm/MC/MCExpr.h"
  22 #include "llvm/MC/MCInst.h"
  23 #include "llvm/MC/MCInstPrinter.h"
  24 #include "llvm/MC/MCObjectFileInfo.h"
  25 #include "llvm/MC/MCPseudoProbe.h"
  26 #include "llvm/MC/MCRegister.h"
  27 #include "llvm/MC/MCRegisterInfo.h"
  28 #include "llvm/MC/MCSection.h"
  29 #include "llvm/MC/MCSectionCOFF.h"
  30 #include "llvm/MC/MCSymbol.h"
  31 #include "llvm/MC/MCWin64EH.h"
  32 #include "llvm/MC/MCWinEH.h"
  33 #include "llvm/Support/Casting.h"
  34 #include "llvm/Support/ErrorHandling.h"
  35 #include "llvm/Support/LEB128.h"
  36 #include "llvm/Support/MathExtras.h"
  37 #include "llvm/Support/raw_ostream.h"
  38 #include <cassert>
  39 #include <cstdint>
  40 #include <cstdlib>
  41 #include <utility>
  42
  43 using namespace llvm;
  44
  45 MCTargetStreamer::MCTargetStreamer(MCStreamer &S) : Streamer(S) {
  46   S.setTargetStreamer(this);
  47 }
  48
  49 // Pin the vtables to this file.
  50 MCTargetStreamer::~MCTargetStreamer() = default;
  51
  52 void MCTargetStreamer::emitLabel(MCSymbol *Symbol) {}
  53
  54 void MCTargetStreamer::finish() {}
  55
  56 void MCTargetStreamer::emitConstantPools() {}
  57
  58 void MCTargetStreamer::changeSection(const MCSection *CurSection,
  59                                      MCSection *Section,
  60                                      const MCExpr *Subsection,
  61                                      raw_ostream &OS) {
  62   Section->PrintSwitchToSection(*Streamer.getContext().getAsmInfo(),
  63                                 Streamer.getContext().getTargetTriple(), OS,
  64                                 Subsection);
  65 }
  66
  67 void MCTargetStreamer::emitDwarfFileDirective(StringRef Directive) {
  68   Streamer.emitRawText(Directive);
  69 }
  70
  71 void MCTargetStreamer::emitValue(const MCExpr *Value) {
  72   SmallString<128> Str;
  73   raw_svector_ostream OS(Str);
  74
  75   Value->print(OS, Streamer.getContext().getAsmInfo());
  76   Streamer.emitRawText(OS.str());
  77 }
  78
  79 void MCTargetStreamer::emitRawBytes(StringRef Data) {
  80   const MCAsmInfo *MAI = Streamer.getContext().getAsmInfo();
  81   const char *Directive = MAI->getData8bitsDirective();
  82   for (const unsigned char C : Data.bytes()) {
  83     SmallString<128> Str;
  84     raw_svector_ostream OS(Str);
  85
  86     OS << Directive << (unsigned)C;
  87     Streamer.emitRawText(OS.str());
  88   }
  89 }
  90
  91 void MCTargetStreamer::emitAssignment(MCSymbol *Symbol, const MCExpr *Value) {}
  92
  93 MCStreamer::MCStreamer(MCContext &Ctx)
  94     : Context(Ctx), CurrentWinFrameInfo(nullptr),
  95       CurrentProcWinFrameInfoStartIndex(0), UseAssemblerInfoForParsing(false) {
  96   SectionStack.push_back(std::pair<MCSectionSubPair, MCSectionSubPair>());
  97 }
  98
  99 MCStreamer::~MCStreamer() {}
 100
 101 void MCStreamer::reset() {
 102   DwarfFrameInfos.clear();
 103   CurrentWinFrameInfo = nullptr;
 104   WinFrameInfos.clear();
 105   SymbolOrdering.clear();
 106   SectionStack.clear();
 107   SectionStack.push_back(std::pair<MCSectionSubPair, MCSectionSubPair>());
 108 }
 109
 110 raw_ostream &MCStreamer::GetCommentOS() {
 111   // By default, discard comments.
 112   return nulls();
 113 }
 114
 115 unsigned MCStreamer::getNumFrameInfos() { return DwarfFrameInfos.size(); }
 116 ArrayRef<MCDwarfFrameInfo> MCStreamer::getDwarfFrameInfos() const {
 117   return DwarfFrameInfos;
 118 }
 119
 120 void MCStreamer::emitRawComment(const Twine &T, bool TabPrefix) {}
 121
 122 void MCStreamer::addExplicitComment(const Twine &T) {}
 123 void MCStreamer::emitExplicitComments() {}
 124
 125 void MCStreamer::generateCompactUnwindEncodings(MCAsmBackend *MAB) {
 126   for (auto &FI : DwarfFrameInfos)
 127     FI.CompactUnwindEncoding =
 128         (MAB ? MAB->generateCompactUnwindEncoding(FI.Instructions) : 0);
 129 }
 130
 131 /// EmitIntValue - Special case of EmitValue that avoids the client having to
 132 /// pass in a MCExpr for constant integers.
 133 void MCStreamer::emitIntValue(uint64_t Value, unsigned Size) {
 134   assert(1 <= Size && Size <= 8 && "Invalid size");
 135   assert((isUIntN(8 * Size, Value) || isIntN(8 * Size, Value)) &&
 136          "Invalid size");
 137   const bool IsLittleEndian = Context.getAsmInfo()->isLittleEndian();
 138   uint64_t Swapped = support::endian::byte_swap(
 139       Value, IsLittleEndian ? support::little : support::big);
 140   unsigned Index = IsLittleEndian ? 0 : 8 - Size;
 141   emitBytes(StringRef(reinterpret_cast<char *>(&Swapped) + Index, Size));
 142 }
 143 void MCStreamer::emitIntValue(APInt Value) {
 144   if (Value.getNumWords() == 1) {
 145     emitIntValue(Value.getLimitedValue(), Value.getBitWidth() / 8);
 146     return;
 147   }
 148
 149   const bool IsLittleEndianTarget = Context.getAsmInfo()->isLittleEndian();
 150   const bool ShouldSwap = sys::IsLittleEndianHost != IsLittleEndianTarget;
 151   const APInt Swapped = ShouldSwap ? Value.byteSwap() : Value;
 152   const unsigned Size = Value.getBitWidth() / 8;
 153   SmallString<10> Tmp;
 154   Tmp.resize(Size);
 155   StoreIntToMemory(Swapped, reinterpret_cast<uint8_t *>(Tmp.data()), Size);
 156   emitBytes(Tmp.str());
 157 }
 158
 159 /// EmitULEB128IntValue - Special case of EmitULEB128Value that avoids the
 160 /// client having to pass in a MCExpr for constant integers.
 161 void MCStreamer::emitULEB128IntValue(uint64_t Value, unsigned PadTo) {
 162   SmallString<128> Tmp;
 163   raw_svector_ostream OSE(Tmp);
 164   encodeULEB128(Value, OSE, PadTo);
 165   emitBytes(OSE.str());
 166 }
 167
 168 /// EmitSLEB128IntValue - Special case of EmitSLEB128Value that avoids the
 169 /// client having to pass in a MCExpr for constant integers.
 170 void MCStreamer::emitSLEB128IntValue(int64_t Value) {
 171   SmallString<128> Tmp;
 172   raw_svector_ostream OSE(Tmp);
 173   encodeSLEB128(Value, OSE);
 174   emitBytes(OSE.str());
 175 }
 176
 177 void MCStreamer::emitValue(const MCExpr *Value, unsigned Size, SMLoc Loc) {
 178   emitValueImpl(Value, Size, Loc);
 179 }
 180
 181 void MCStreamer::emitSymbolValue(const MCSymbol *Sym, unsigned Size,
 182                                  bool IsSectionRelative) {
 183   assert((!IsSectionRelative || Size == 4) &&
 184          "SectionRelative value requires 4-bytes");
 185
 186   if (!IsSectionRelative)
 187     emitValueImpl(MCSymbolRefExpr::create(Sym, getContext()), Size);
 188   else
 189     EmitCOFFSecRel32(Sym, /*Offset=*/0);
 190 }
 191
 192 void MCStreamer::emitDTPRel64Value(const MCExpr *Value) {
 193   report_fatal_error("unsupported directive in streamer");
 194 }
 195
 196 void MCStreamer::emitDTPRel32Value(const MCExpr *Value) {
 197   report_fatal_error("unsupported directive in streamer");
 198 }
 199
 200 void MCStreamer::emitTPRel64Value(const MCExpr *Value) {
 201   report_fatal_error("unsupported directive in streamer");
 202 }
 203
 204 void MCStreamer::emitTPRel32Value(const MCExpr *Value) {
 205   report_fatal_error("unsupported directive in streamer");
 206 }
 207
 208 void MCStreamer::emitGPRel64Value(const MCExpr *Value) {
 209   report_fatal_error("unsupported directive in streamer");
 210 }
 211
 212 void MCStreamer::emitGPRel32Value(const MCExpr *Value) {
 213   report_fatal_error("unsupported directive in streamer");
 214 }
 215
 216 /// Emit NumBytes bytes worth of the value specified by FillValue.
 217 /// This implements directives such as '.space'.
 218 void MCStreamer::emitFill(uint64_t NumBytes, uint8_t FillValue) {
 219   emitFill(*MCConstantExpr::create(NumBytes, getContext()), FillValue);
 220 }
 221
 222 void llvm::MCStreamer::emitNops(int64_t NumBytes, int64_t ControlledNopLen,
 223                                 llvm::SMLoc, const MCSubtargetInfo& STI) {}
 224
 225 /// The implementation in this class just redirects to emitFill.
 226 void MCStreamer::emitZeros(uint64_t NumBytes) { emitFill(NumBytes, 0); }
 227
 228 Expected<unsigned>
 229 MCStreamer::tryEmitDwarfFileDirective(unsigned FileNo, StringRef Directory,
 230                                       StringRef Filename,
 231                                       Optional<MD5::MD5Result> Checksum,
 232                                       Optional<StringRef> Source,
 233                                       unsigned CUID) {
 234   return getContext().getDwarfFile(Directory, Filename, FileNo, Checksum,
 235                                    Source, CUID);
 236 }
 237
 238 void MCStreamer::emitDwarfFile0Directive(StringRef Directory,
 239                                          StringRef Filename,
 240                                          Optional<MD5::MD5Result> Checksum,
 241                                          Optional<StringRef> Source,
 242                                          unsigned CUID) {
 243   getContext().setMCLineTableRootFile(CUID, Directory, Filename, Checksum,
 244                                       Source);
 245 }
 246
 247 void MCStreamer::emitCFIBKeyFrame() {
 248   MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo();
 249   if (!CurFrame)
 250     return;
 251   CurFrame->IsBKeyFrame = true;
 252 }
 253
 254 void MCStreamer::emitDwarfLocDirective(unsigned FileNo, unsigned Line,
 255                                        unsigned Column, unsigned Flags,
 256                                        unsigned Isa, unsigned Discriminator,
 257                                        StringRef FileName) {
 258   getContext().setCurrentDwarfLoc(FileNo, Line, Column, Flags, Isa,
 259                                   Discriminator);
 260 }
 261
 262 MCSymbol *MCStreamer::getDwarfLineTableSymbol(unsigned CUID) {
 263   MCDwarfLineTable &Table = getContext().getMCDwarfLineTable(CUID);
 264   if (!Table.getLabel()) {
 265     StringRef Prefix = Context.getAsmInfo()->getPrivateGlobalPrefix();
 266     Table.setLabel(
 267         Context.getOrCreateSymbol(Prefix + "line_table_start" + Twine(CUID)));
 268   }
 269   return Table.getLabel();
 270 }
 271
 272 bool MCStreamer::hasUnfinishedDwarfFrameInfo() {
 273   return !DwarfFrameInfos.empty() && !DwarfFrameInfos.back().End;
 274 }
 275
 276 MCDwarfFrameInfo *MCStreamer::getCurrentDwarfFrameInfo() {
 277   if (!hasUnfinishedDwarfFrameInfo()) {
 278     getContext().reportError(getStartTokLoc(),
 279                              "this directive must appear between "
 280                              ".cfi_startproc and .cfi_endproc directives");
 281     return nullptr;
 282   }
 283   return &DwarfFrameInfos.back();
 284 }
 285
 286 bool MCStreamer::EmitCVFileDirective(unsigned FileNo, StringRef Filename,
 287                                      ArrayRef<uint8_t> Checksum,
 288                                      unsigned ChecksumKind) {
 289   return getContext().getCVContext().addFile(*this, FileNo, Filename, Checksum,
 290                                              ChecksumKind);
 291 }
 292
 293 bool MCStreamer::EmitCVFuncIdDirective(unsigned FunctionId) {
 294   return getContext().getCVContext().recordFunctionId(FunctionId);
 295 }
 296
 297 bool MCStreamer::EmitCVInlineSiteIdDirective(unsigned FunctionId,
 298                                              unsigned IAFunc, unsigned IAFile,
 299                                              unsigned IALine, unsigned IACol,
 300                                              SMLoc Loc) {
 301   if (getContext().getCVContext().getCVFunctionInfo(IAFunc) == nullptr) {
 302     getContext().reportError(Loc, "parent function id not introduced by "
 303                                   ".cv_func_id or .cv_inline_site_id");
 304     return true;
 305   }
 306
 307   return getContext().getCVContext().recordInlinedCallSiteId(
 308       FunctionId, IAFunc, IAFile, IALine, IACol);
 309 }
 310
 311 void MCStreamer::emitCVLocDirective(unsigned FunctionId, unsigned FileNo,
 312                                     unsigned Line, unsigned Column,
 313                                     bool PrologueEnd, bool IsStmt,
 314                                     StringRef FileName, SMLoc Loc) {}
 315
 316 bool MCStreamer::checkCVLocSection(unsigned FuncId, unsigned FileNo,
 317                                    SMLoc Loc) {
 318   CodeViewContext &CVC = getContext().getCVContext();
 319   MCCVFunctionInfo *FI = CVC.getCVFunctionInfo(FuncId);
 320   if (!FI) {
 321     getContext().reportError(
 322         Loc, "function id not introduced by .cv_func_id or .cv_inline_site_id");
 323     return false;
 324   }
 325
 326   // Track the section
 327   if (FI->Section == nullptr)
 328     FI->Section = getCurrentSectionOnly();
 329   else if (FI->Section != getCurrentSectionOnly()) {
 330     getContext().reportError(
 331         Loc,
 332         "all .cv_loc directives for a function must be in the same section");
 333     return false;
 334   }
 335   return true;
 336 }
 337
 338 void MCStreamer::emitCVLinetableDirective(unsigned FunctionId,
 339                                           const MCSymbol *Begin,
 340                                           const MCSymbol *End) {}
 341
 342 void MCStreamer::emitCVInlineLinetableDirective(unsigned PrimaryFunctionId,
 343                                                 unsigned SourceFileId,
 344                                                 unsigned SourceLineNum,
 345                                                 const MCSymbol *FnStartSym,
 346                                                 const MCSymbol *FnEndSym) {}
 347
 348 /// Only call this on endian-specific types like ulittle16_t and little32_t, or
 349 /// structs composed of them.
 350 template <typename T>
 351 static void copyBytesForDefRange(SmallString<20> &BytePrefix,
 352                                  codeview::SymbolKind SymKind,
 353                                  const T &DefRangeHeader) {
 354   BytePrefix.resize(2 + sizeof(T));
 355   codeview::ulittle16_t SymKindLE = codeview::ulittle16_t(SymKind);
 356   memcpy(&BytePrefix[0], &SymKindLE, 2);
 357   memcpy(&BytePrefix[2], &DefRangeHeader, sizeof(T));
 358 }
 359
 360 void MCStreamer::emitCVDefRangeDirective(
 361     ArrayRef<std::pair<const MCSymbol *, const MCSymbol *>> Ranges,
 362     StringRef FixedSizePortion) {}
 363
 364 void MCStreamer::emitCVDefRangeDirective(
 365     ArrayRef<std::pair<const MCSymbol *, const MCSymbol *>> Ranges,
 366     codeview::DefRangeRegisterRelHeader DRHdr) {
 367   SmallString<20> BytePrefix;
 368   copyBytesForDefRange(BytePrefix, codeview::S_DEFRANGE_REGISTER_REL, DRHdr);
 369   emitCVDefRangeDirective(Ranges, BytePrefix);
 370 }
 371
 372 void MCStreamer::emitCVDefRangeDirective(
 373     ArrayRef<std::pair<const MCSymbol *, const MCSymbol *>> Ranges,
 374     codeview::DefRangeSubfieldRegisterHeader DRHdr) {
 375   SmallString<20> BytePrefix;
 376   copyBytesForDefRange(BytePrefix, codeview::S_DEFRANGE_SUBFIELD_REGISTER,
 377                        DRHdr);
 378   emitCVDefRangeDirective(Ranges, BytePrefix);
 379 }
 380
 381 void MCStreamer::emitCVDefRangeDirective(
 382     ArrayRef<std::pair<const MCSymbol *, const MCSymbol *>> Ranges,
 383     codeview::DefRangeRegisterHeader DRHdr) {
 384   SmallString<20> BytePrefix;
 385   copyBytesForDefRange(BytePrefix, codeview::S_DEFRANGE_REGISTER, DRHdr);
 386   emitCVDefRangeDirective(Ranges, BytePrefix);
 387 }
 388
 389 void MCStreamer::emitCVDefRangeDirective(
 390     ArrayRef<std::pair<const MCSymbol *, const MCSymbol *>> Ranges,
 391     codeview::DefRangeFramePointerRelHeader DRHdr) {
 392   SmallString<20> BytePrefix;
 393   copyBytesForDefRange(BytePrefix, codeview::S_DEFRANGE_FRAMEPOINTER_REL,
 394                        DRHdr);
 395   emitCVDefRangeDirective(Ranges, BytePrefix);
 396 }
 397
 398 void MCStreamer::emitEHSymAttributes(const MCSymbol *Symbol,
 399                                      MCSymbol *EHSymbol) {
 400 }
 401
 402 void MCStreamer::initSections(bool NoExecStack, const MCSubtargetInfo &STI) {
 403   SwitchSection(getContext().getObjectFileInfo()->getTextSection());
 404 }
 405
 406 void MCStreamer::AssignFragment(MCSymbol *Symbol, MCFragment *Fragment) {
 407   assert(Fragment);
 408   Symbol->setFragment(Fragment);
 409
 410   // As we emit symbols into a section, track the order so that they can
 411   // be sorted upon later. Zero is reserved to mean 'unemitted'.
 412   SymbolOrdering[Symbol] = 1 + SymbolOrdering.size();
 413 }
 414
 415 void MCStreamer::emitLabel(MCSymbol *Symbol, SMLoc Loc) {
 416   Symbol->redefineIfPossible();
 417
 418   if (!Symbol->isUndefined() || Symbol->isVariable())
 419     return getContext().reportError(Loc, "symbol '" + Twine(Symbol->getName()) +
 420                                              "' is already defined");
 421
 422   assert(!Symbol->isVariable() && "Cannot emit a variable symbol!");
 423   assert(getCurrentSectionOnly() && "Cannot emit before setting section!");
 424   assert(!Symbol->getFragment() && "Unexpected fragment on symbol data!");
 425   assert(Symbol->isUndefined() && "Cannot define a symbol twice!");
 426
 427   Symbol->setFragment(&getCurrentSectionOnly()->getDummyFragment());
 428
 429   MCTargetStreamer *TS = getTargetStreamer();
 430   if (TS)
 431     TS->emitLabel(Symbol);
 432 }
 433
 434 void MCStreamer::emitCFISections(bool EH, bool Debug) {}
 435
 436 void MCStreamer::emitCFIStartProc(bool IsSimple, SMLoc Loc) {
 437   if (hasUnfinishedDwarfFrameInfo())
 438     return getContext().reportError(
 439         Loc, "starting new .cfi frame before finishing the previous one");
 440
 441   MCDwarfFrameInfo Frame;
 442   Frame.IsSimple = IsSimple;
 443   emitCFIStartProcImpl(Frame);
 444
 445   const MCAsmInfo* MAI = Context.getAsmInfo();
 446   if (MAI) {
 447     for (const MCCFIInstruction& Inst : MAI->getInitialFrameState()) {
 448       if (Inst.getOperation() == MCCFIInstruction::OpDefCfa ||
 449           Inst.getOperation() == MCCFIInstruction::OpDefCfaRegister ||
 450           Inst.getOperation() == MCCFIInstruction::OpLLVMDefAspaceCfa) {
 451         Frame.CurrentCfaRegister = Inst.getRegister();
 452       }
 453     }
 454   }
 455
 456   DwarfFrameInfos.push_back(Frame);
 457 }
 458
 459 void MCStreamer::emitCFIStartProcImpl(MCDwarfFrameInfo &Frame) {
 460 }
 461
 462 void MCStreamer::emitCFIEndProc() {
 463   MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo();
 464   if (!CurFrame)
 465     return;
 466   emitCFIEndProcImpl(*CurFrame);
 467 }
 468
 469 void MCStreamer::emitCFIEndProcImpl(MCDwarfFrameInfo &Frame) {
 470   // Put a dummy non-null value in Frame.End to mark that this frame has been
 471   // closed.
 472   Frame.End = (MCSymbol *)1;
 473 }
 474
 475 MCSymbol *MCStreamer::emitCFILabel() {
 476   // Return a dummy non-null value so that label fields appear filled in when
 477   // generating textual assembly.
 478   return (MCSymbol *)1;
 479 }
 480
 481 void MCStreamer::emitCFIDefCfa(int64_t Register, int64_t Offset) {
 482   MCSymbol *Label = emitCFILabel();
 483   MCCFIInstruction Instruction =
 484       MCCFIInstruction::cfiDefCfa(Label, Register, Offset);
 485   MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo();
 486   if (!CurFrame)
 487     return;
 488   CurFrame->Instructions.push_back(Instruction);
 489   CurFrame->CurrentCfaRegister = static_cast<unsigned>(Register);
 490 }
 491
 492 void MCStreamer::emitCFIDefCfaOffset(int64_t Offset) {
 493   MCSymbol *Label = emitCFILabel();
 494   MCCFIInstruction Instruction =
 495       MCCFIInstruction::cfiDefCfaOffset(Label, Offset);
 496   MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo();
 497   if (!CurFrame)
 498     return;
 499   CurFrame->Instructions.push_back(Instruction);
 500 }
 501
 502 void MCStreamer::emitCFIAdjustCfaOffset(int64_t Adjustment) {
 503   MCSymbol *Label = emitCFILabel();
 504   MCCFIInstruction Instruction =
 505     MCCFIInstruction::createAdjustCfaOffset(Label, Adjustment);
 506   MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo();
 507   if (!CurFrame)
 508     return;
 509   CurFrame->Instructions.push_back(Instruction);
 510 }
 511
 512 void MCStreamer::emitCFIDefCfaRegister(int64_t Register) {
 513   MCSymbol *Label = emitCFILabel();
 514   MCCFIInstruction Instruction =
 515     MCCFIInstruction::createDefCfaRegister(Label, Register);
 516   MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo();
 517   if (!CurFrame)
 518     return;
 519   CurFrame->Instructions.push_back(Instruction);
 520   CurFrame->CurrentCfaRegister = static_cast<unsigned>(Register);
 521 }
 522
 523 void MCStreamer::emitCFILLVMDefAspaceCfa(int64_t Register, int64_t Offset,
 524                                          int64_t AddressSpace) {
 525   MCSymbol *Label = emitCFILabel();
 526   MCCFIInstruction Instruction = MCCFIInstruction::createLLVMDefAspaceCfa(
 527       Label, Register, Offset, AddressSpace);
 528   MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo();
 529   if (!CurFrame)
 530     return;
 531   CurFrame->Instructions.push_back(Instruction);
 532   CurFrame->CurrentCfaRegister = static_cast<unsigned>(Register);
 533 }
 534
 535 void MCStreamer::emitCFIOffset(int64_t Register, int64_t Offset) {
 536   MCSymbol *Label = emitCFILabel();
 537   MCCFIInstruction Instruction =
 538     MCCFIInstruction::createOffset(Label, Register, Offset);
 539   MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo();
 540   if (!CurFrame)
 541     return;
 542   CurFrame->Instructions.push_back(Instruction);
 543 }
 544
 545 void MCStreamer::emitCFIRelOffset(int64_t Register, int64_t Offset) {
 546   MCSymbol *Label = emitCFILabel();
 547   MCCFIInstruction Instruction =
 548     MCCFIInstruction::createRelOffset(Label, Register, Offset);
 549   MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo();
 550   if (!CurFrame)
 551     return;
 552   CurFrame->Instructions.push_back(Instruction);
 553 }
 554
 555 void MCStreamer::emitCFIPersonality(const MCSymbol *Sym,
 556                                     unsigned Encoding) {
 557   MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo();
 558   if (!CurFrame)
 559     return;
 560   CurFrame->Personality = Sym;
 561   CurFrame->PersonalityEncoding = Encoding;
 562 }
 563
 564 void MCStreamer::emitCFILsda(const MCSymbol *Sym, unsigned Encoding) {
 565   MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo();
 566   if (!CurFrame)
 567     return;
 568   CurFrame->Lsda = Sym;
 569   CurFrame->LsdaEncoding = Encoding;
 570 }
 571
 572 void MCStreamer::emitCFIRememberState() {
 573   MCSymbol *Label = emitCFILabel();
 574   MCCFIInstruction Instruction = MCCFIInstruction::createRememberState(Label);
 575   MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo();
 576   if (!CurFrame)
 577     return;
 578   CurFrame->Instructions.push_back(Instruction);
 579 }
 580
 581 void MCStreamer::emitCFIRestoreState() {
 582   // FIXME: Error if there is no matching cfi_remember_state.
 583   MCSymbol *Label = emitCFILabel();
 584   MCCFIInstruction Instruction = MCCFIInstruction::createRestoreState(Label);
 585   MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo();
 586   if (!CurFrame)
 587     return;
 588   CurFrame->Instructions.push_back(Instruction);
 589 }
 590
 591 void MCStreamer::emitCFISameValue(int64_t Register) {
 592   MCSymbol *Label = emitCFILabel();
 593   MCCFIInstruction Instruction =
 594     MCCFIInstruction::createSameValue(Label, Register);
 595   MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo();
 596   if (!CurFrame)
 597     return;
 598   CurFrame->Instructions.push_back(Instruction);
 599 }
 600
 601 void MCStreamer::emitCFIRestore(int64_t Register) {
 602   MCSymbol *Label = emitCFILabel();
 603   MCCFIInstruction Instruction =
 604     MCCFIInstruction::createRestore(Label, Register);
 605   MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo();
 606   if (!CurFrame)
 607     return;
 608   CurFrame->Instructions.push_back(Instruction);
 609 }
 610
 611 void MCStreamer::emitCFIEscape(StringRef Values) {
 612   MCSymbol *Label = emitCFILabel();
 613   MCCFIInstruction Instruction = MCCFIInstruction::createEscape(Label, Values);
 614   MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo();
 615   if (!CurFrame)
 616     return;
 617   CurFrame->Instructions.push_back(Instruction);
 618 }
 619
 620 void MCStreamer::emitCFIGnuArgsSize(int64_t Size) {
 621   MCSymbol *Label = emitCFILabel();
 622   MCCFIInstruction Instruction =
 623     MCCFIInstruction::createGnuArgsSize(Label, Size);
 624   MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo();
 625   if (!CurFrame)
 626     return;
 627   CurFrame->Instructions.push_back(Instruction);
 628 }
 629
 630 void MCStreamer::emitCFISignalFrame() {
 631   MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo();
 632   if (!CurFrame)
 633     return;
 634   CurFrame->IsSignalFrame = true;
 635 }
 636
 637 void MCStreamer::emitCFIUndefined(int64_t Register) {
 638   MCSymbol *Label = emitCFILabel();
 639   MCCFIInstruction Instruction =
 640     MCCFIInstruction::createUndefined(Label, Register);
 641   MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo();
 642   if (!CurFrame)
 643     return;
 644   CurFrame->Instructions.push_back(Instruction);
 645 }
 646
 647 void MCStreamer::emitCFIRegister(int64_t Register1, int64_t Register2) {
 648   MCSymbol *Label = emitCFILabel();
 649   MCCFIInstruction Instruction =
 650     MCCFIInstruction::createRegister(Label, Register1, Register2);
 651   MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo();
 652   if (!CurFrame)
 653     return;
 654   CurFrame->Instructions.push_back(Instruction);
 655 }
 656
 657 void MCStreamer::emitCFIWindowSave() {
 658   MCSymbol *Label = emitCFILabel();
 659   MCCFIInstruction Instruction =
 660     MCCFIInstruction::createWindowSave(Label);
 661   MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo();
 662   if (!CurFrame)
 663     return;
 664   CurFrame->Instructions.push_back(Instruction);
 665 }
 666
 667 void MCStreamer::emitCFINegateRAState() {
 668   MCSymbol *Label = emitCFILabel();
 669   MCCFIInstruction Instruction = MCCFIInstruction::createNegateRAState(Label);
 670   MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo();
 671   if (!CurFrame)
 672     return;
 673   CurFrame->Instructions.push_back(Instruction);
 674 }
 675
 676 void MCStreamer::emitCFIReturnColumn(int64_t Register) {
 677   MCDwarfFrameInfo *CurFrame = getCurrentDwarfFrameInfo();
 678   if (!CurFrame)
 679     return;
 680   CurFrame->RAReg = Register;
 681 }
 682
 683 WinEH::FrameInfo *MCStreamer::EnsureValidWinFrameInfo(SMLoc Loc) {
 684   const MCAsmInfo *MAI = Context.getAsmInfo();
 685   if (!MAI->usesWindowsCFI()) {
 686     getContext().reportError(
 687         Loc, ".seh_* directives are not supported on this target");
 688     return nullptr;
 689   }
 690   if (!CurrentWinFrameInfo || CurrentWinFrameInfo->End) {
 691     getContext().reportError(
 692         Loc, ".seh_ directive must appear within an active frame");
 693     return nullptr;
 694   }
 695   return CurrentWinFrameInfo;
 696 }
 697
 698 void MCStreamer::EmitWinCFIStartProc(const MCSymbol *Symbol, SMLoc Loc) {
 699   const MCAsmInfo *MAI = Context.getAsmInfo();
 700   if (!MAI->usesWindowsCFI())
 701     return getContext().reportError(
 702         Loc, ".seh_* directives are not supported on this target");
 703   if (CurrentWinFrameInfo && !CurrentWinFrameInfo->End)
 704     getContext().reportError(
 705         Loc, "Starting a function before ending the previous one!");
 706
 707   MCSymbol *StartProc = emitCFILabel();
 708
 709   CurrentProcWinFrameInfoStartIndex = WinFrameInfos.size();
 710   WinFrameInfos.emplace_back(
 711       std::make_unique<WinEH::FrameInfo>(Symbol, StartProc));
 712   CurrentWinFrameInfo = WinFrameInfos.back().get();
 713   CurrentWinFrameInfo->TextSection = getCurrentSectionOnly();
 714 }
 715
 716 void MCStreamer::EmitWinCFIEndProc(SMLoc Loc) {
 717   WinEH::FrameInfo *CurFrame = EnsureValidWinFrameInfo(Loc);
 718   if (!CurFrame)
 719     return;
 720   if (CurFrame->ChainedParent)
 721     getContext().reportError(Loc, "Not all chained regions terminated!");
 722
 723   MCSymbol *Label = emitCFILabel();
 724   CurFrame->End = Label;
 725   if (!CurFrame->FuncletOrFuncEnd)
 726     CurFrame->FuncletOrFuncEnd = CurFrame->End;
 727
 728   for (size_t I = CurrentProcWinFrameInfoStartIndex, E = WinFrameInfos.size();
 729        I != E; ++I)
 730     EmitWindowsUnwindTables(WinFrameInfos[I].get());
 731   SwitchSection(CurFrame->TextSection);
 732 }
 733
 734 void MCStreamer::EmitWinCFIFuncletOrFuncEnd(SMLoc Loc) {
 735   WinEH::FrameInfo *CurFrame = EnsureValidWinFrameInfo(Loc);
 736   if (!CurFrame)
 737     return;
 738   if (CurFrame->ChainedParent)
 739     getContext().reportError(Loc, "Not all chained regions terminated!");
 740
 741   MCSymbol *Label = emitCFILabel();
 742   CurFrame->FuncletOrFuncEnd = Label;
 743 }
 744
 745 void MCStreamer::EmitWinCFIStartChained(SMLoc Loc) {
 746   WinEH::FrameInfo *CurFrame = EnsureValidWinFrameInfo(Loc);
 747   if (!CurFrame)
 748     return;
 749
 750   MCSymbol *StartProc = emitCFILabel();
 751
 752   WinFrameInfos.emplace_back(std::make_unique<WinEH::FrameInfo>(
 753       CurFrame->Function, StartProc, CurFrame));
 754   CurrentWinFrameInfo = WinFrameInfos.back().get();
 755   CurrentWinFrameInfo->TextSection = getCurrentSectionOnly();
 756 }
 757
 758 void MCStreamer::EmitWinCFIEndChained(SMLoc Loc) {
 759   WinEH::FrameInfo *CurFrame = EnsureValidWinFrameInfo(Loc);
 760   if (!CurFrame)
 761     return;
 762   if (!CurFrame->ChainedParent)
 763     return getContext().reportError(
 764         Loc, "End of a chained region outside a chained region!");
 765
 766   MCSymbol *Label = emitCFILabel();
 767
 768   CurFrame->End = Label;
 769   CurrentWinFrameInfo = const_cast<WinEH::FrameInfo *>(CurFrame->ChainedParent);
 770 }
 771
 772 void MCStreamer::EmitWinEHHandler(const MCSymbol *Sym, bool Unwind, bool Except,
 773                                   SMLoc Loc) {
 774   WinEH::FrameInfo *CurFrame = EnsureValidWinFrameInfo(Loc);
 775   if (!CurFrame)
 776     return;
 777   if (CurFrame->ChainedParent)
 778     return getContext().reportError(
 779         Loc, "Chained unwind areas can't have handlers!");
 780   CurFrame->ExceptionHandler = Sym;
 781   if (!Except && !Unwind)
 782     getContext().reportError(Loc, "Don't know what kind of handler this is!");
 783   if (Unwind)
 784     CurFrame->HandlesUnwind = true;
 785   if (Except)
 786     CurFrame->HandlesExceptions = true;
 787 }
 788
 789 void MCStreamer::EmitWinEHHandlerData(SMLoc Loc) {
 790   WinEH::FrameInfo *CurFrame = EnsureValidWinFrameInfo(Loc);
 791   if (!CurFrame)
 792     return;
 793   if (CurFrame->ChainedParent)
 794     getContext().reportError(Loc, "Chained unwind areas can't have handlers!");
 795 }
 796
 797 void MCStreamer::emitCGProfileEntry(const MCSymbolRefExpr *From,
 798                                     const MCSymbolRefExpr *To, uint64_t Count) {
 799 }
 800
 801 static MCSection *getWinCFISection(MCContext &Context, unsigned *NextWinCFIID,
 802                                    MCSection *MainCFISec,
 803                                    const MCSection *TextSec) {
 804   // If this is the main .text section, use the main unwind info section.
 805   if (TextSec == Context.getObjectFileInfo()->getTextSection())
 806     return MainCFISec;
 807
 808   const auto *TextSecCOFF = cast<MCSectionCOFF>(TextSec);
 809   auto *MainCFISecCOFF = cast<MCSectionCOFF>(MainCFISec);
 810   unsigned UniqueID = TextSecCOFF->getOrAssignWinCFISectionID(NextWinCFIID);
 811
 812   // If this section is COMDAT, this unwind section should be COMDAT associative
 813   // with its group.
 814   const MCSymbol *KeySym = nullptr;
 815   if (TextSecCOFF->getCharacteristics() & COFF::IMAGE_SCN_LNK_COMDAT) {
 816     KeySym = TextSecCOFF->getCOMDATSymbol();
 817
 818     // In a GNU environment, we can't use associative comdats. Instead, do what
 819     // GCC does, which is to make plain comdat selectany section named like
 820     // ".[px]data$_Z3foov".
 821     if (!Context.getAsmInfo()->hasCOFFAssociativeComdats()) {
 822       std::string SectionName = (MainCFISecCOFF->getName() + "$" +
 823                                  TextSecCOFF->getName().split('$').second)
 824                                     .str();
 825       return Context.getCOFFSection(
 826           SectionName,
 827           MainCFISecCOFF->getCharacteristics() | COFF::IMAGE_SCN_LNK_COMDAT,
 828           MainCFISecCOFF->getKind(), "", COFF::IMAGE_COMDAT_SELECT_ANY);
 829     }
 830   }
 831
 832   return Context.getAssociativeCOFFSection(MainCFISecCOFF, KeySym, UniqueID);
 833 }
 834
 835 MCSection *MCStreamer::getAssociatedPDataSection(const MCSection *TextSec) {
 836   return getWinCFISection(getContext(), &NextWinCFIID,
 837                           getContext().getObjectFileInfo()->getPDataSection(),
 838                           TextSec);
 839 }
 840
 841 MCSection *MCStreamer::getAssociatedXDataSection(const MCSection *TextSec) {
 842   return getWinCFISection(getContext(), &NextWinCFIID,
 843                           getContext().getObjectFileInfo()->getXDataSection(),
 844                           TextSec);
 845 }
 846
 847 void MCStreamer::emitSyntaxDirective() {}
 848
 849 static unsigned encodeSEHRegNum(MCContext &Ctx, MCRegister Reg) {
 850   return Ctx.getRegisterInfo()->getSEHRegNum(Reg);
 851 }
 852
 853 void MCStreamer::EmitWinCFIPushReg(MCRegister Register, SMLoc Loc) {
 854   WinEH::FrameInfo *CurFrame = EnsureValidWinFrameInfo(Loc);
 855   if (!CurFrame)
 856     return;
 857
 858   MCSymbol *Label = emitCFILabel();
 859
 860   WinEH::Instruction Inst = Win64EH::Instruction::PushNonVol(
 861       Label, encodeSEHRegNum(Context, Register));
 862   CurFrame->Instructions.push_back(Inst);
 863 }
 864
 865 void MCStreamer::EmitWinCFISetFrame(MCRegister Register, unsigned Offset,
 866                                     SMLoc Loc) {
 867   WinEH::FrameInfo *CurFrame = EnsureValidWinFrameInfo(Loc);
 868   if (!CurFrame)
 869     return;
 870   if (CurFrame->LastFrameInst >= 0)
 871     return getContext().reportError(
 872         Loc, "frame register and offset can be set at most once");
 873   if (Offset & 0x0F)
 874     return getContext().reportError(Loc, "offset is not a multiple of 16");
 875   if (Offset > 240)
 876     return getContext().reportError(
 877         Loc, "frame offset must be less than or equal to 240");
 878
 879   MCSymbol *Label = emitCFILabel();
 880
 881   WinEH::Instruction Inst = Win64EH::Instruction::SetFPReg(
 882       Label, encodeSEHRegNum(getContext(), Register), Offset);
 883   CurFrame->LastFrameInst = CurFrame->Instructions.size();
 884   CurFrame->Instructions.push_back(Inst);
 885 }
 886
 887 void MCStreamer::EmitWinCFIAllocStack(unsigned Size, SMLoc Loc) {
 888   WinEH::FrameInfo *CurFrame = EnsureValidWinFrameInfo(Loc);
 889   if (!CurFrame)
 890     return;
 891   if (Size == 0)
 892     return getContext().reportError(Loc,
 893                                     "stack allocation size must be non-zero");
 894   if (Size & 7)
 895     return getContext().reportError(
 896         Loc, "stack allocation size is not a multiple of 8");
 897
 898   MCSymbol *Label = emitCFILabel();
 899
 900   WinEH::Instruction Inst = Win64EH::Instruction::Alloc(Label, Size);
 901   CurFrame->Instructions.push_back(Inst);
 902 }
 903
 904 void MCStreamer::EmitWinCFISaveReg(MCRegister Register, unsigned Offset,
 905                                    SMLoc Loc) {
 906   WinEH::FrameInfo *CurFrame = EnsureValidWinFrameInfo(Loc);
 907   if (!CurFrame)
 908     return;
 909
 910   if (Offset & 7)
 911     return getContext().reportError(
 912         Loc, "register save offset is not 8 byte aligned");
 913
 914   MCSymbol *Label = emitCFILabel();
 915
 916   WinEH::Instruction Inst = Win64EH::Instruction::SaveNonVol(
 917       Label, encodeSEHRegNum(Context, Register), Offset);
 918   CurFrame->Instructions.push_back(Inst);
 919 }
 920
 921 void MCStreamer::EmitWinCFISaveXMM(MCRegister Register, unsigned Offset,
 922                                    SMLoc Loc) {
 923   WinEH::FrameInfo *CurFrame = EnsureValidWinFrameInfo(Loc);
 924   if (!CurFrame)
 925     return;
 926   if (Offset & 0x0F)
 927     return getContext().reportError(Loc, "offset is not a multiple of 16");
 928
 929   MCSymbol *Label = emitCFILabel();
 930
 931   WinEH::Instruction Inst = Win64EH::Instruction::SaveXMM(
 932       Label, encodeSEHRegNum(Context, Register), Offset);
 933   CurFrame->Instructions.push_back(Inst);
 934 }
 935
 936 void MCStreamer::EmitWinCFIPushFrame(bool Code, SMLoc Loc) {
 937   WinEH::FrameInfo *CurFrame = EnsureValidWinFrameInfo(Loc);
 938   if (!CurFrame)
 939     return;
 940   if (!CurFrame->Instructions.empty())
 941     return getContext().reportError(
 942         Loc, "If present, PushMachFrame must be the first UOP");
 943
 944   MCSymbol *Label = emitCFILabel();
 945
 946   WinEH::Instruction Inst = Win64EH::Instruction::PushMachFrame(Label, Code);
 947   CurFrame->Instructions.push_back(Inst);
 948 }
 949
 950 void MCStreamer::EmitWinCFIEndProlog(SMLoc Loc) {
 951   WinEH::FrameInfo *CurFrame = EnsureValidWinFrameInfo(Loc);
 952   if (!CurFrame)
 953     return;
 954
 955   MCSymbol *Label = emitCFILabel();
 956
 957   CurFrame->PrologEnd = Label;
 958 }
 959
 960 void MCStreamer::EmitCOFFSafeSEH(MCSymbol const *Symbol) {}
 961
 962 void MCStreamer::EmitCOFFSymbolIndex(MCSymbol const *Symbol) {}
 963
 964 void MCStreamer::EmitCOFFSectionIndex(MCSymbol const *Symbol) {}
 965
 966 void MCStreamer::EmitCOFFSecRel32(MCSymbol const *Symbol, uint64_t Offset) {}
 967
 968 void MCStreamer::EmitCOFFImgRel32(MCSymbol const *Symbol, int64_t Offset) {}
 969
 970 /// EmitRawText - If this file is backed by an assembly streamer, this dumps
 971 /// the specified string in the output .s file.  This capability is
 972 /// indicated by the hasRawTextSupport() predicate.
 973 void MCStreamer::emitRawTextImpl(StringRef String) {
 974   // This is not llvm_unreachable for the sake of out of tree backend
 975   // developers who may not have assembly streamers and should serve as a
 976   // reminder to not accidentally call EmitRawText in the absence of such.
 977   report_fatal_error("EmitRawText called on an MCStreamer that doesn't support "
 978                      "it (target backend is likely missing an AsmStreamer "
 979                      "implementation)");
 980 }
 981
 982 void MCStreamer::emitRawText(const Twine &T) {
 983   SmallString<128> Str;
 984   emitRawTextImpl(T.toStringRef(Str));
 985 }
 986
 987 void MCStreamer::EmitWindowsUnwindTables() {
 988 }
 989
 990 void MCStreamer::EmitWindowsUnwindTables(WinEH::FrameInfo *Frame) {
 991 }
 992
 993 void MCStreamer::Finish(SMLoc EndLoc) {
 994   if ((!DwarfFrameInfos.empty() && !DwarfFrameInfos.back().End) ||
 995       (!WinFrameInfos.empty() && !WinFrameInfos.back()->End)) {
 996     getContext().reportError(EndLoc, "Unfinished frame!");
 997     return;
 998   }
 999
1000   MCTargetStreamer *TS = getTargetStreamer();
1001   if (TS)
1002     TS->finish();
1003
1004   finishImpl();
1005 }
1006
1007 void MCStreamer::maybeEmitDwarf64Mark() {
1008   if (Context.getDwarfFormat() != dwarf::DWARF64)
1009     return;
1010   AddComment("DWARF64 Mark");
1011   emitInt32(dwarf::DW_LENGTH_DWARF64);
1012 }
1013
1014 void MCStreamer::emitDwarfUnitLength(uint64_t Length, const Twine &Comment) {
1015   assert(Context.getDwarfFormat() == dwarf::DWARF64 ||
1016          Length <= dwarf::DW_LENGTH_lo_reserved);
1017   maybeEmitDwarf64Mark();
1018   AddComment(Comment);
1019   emitIntValue(Length, dwarf::getDwarfOffsetByteSize(Context.getDwarfFormat()));
1020 }
1021
1022 MCSymbol *MCStreamer::emitDwarfUnitLength(const Twine &Prefix,
1023                                           const Twine &Comment) {
1024   maybeEmitDwarf64Mark();
1025   AddComment(Comment);
1026   MCSymbol *Lo = Context.createTempSymbol(Prefix + "_start");
1027   MCSymbol *Hi = Context.createTempSymbol(Prefix + "_end");
1028
1029   emitAbsoluteSymbolDiff(
1030       Hi, Lo, dwarf::getDwarfOffsetByteSize(Context.getDwarfFormat()));
1031   // emit the begin symbol after we generate the length field.
1032   emitLabel(Lo);
1033   // Return the Hi symbol to the caller.
1034   return Hi;
1035 }
1036
1037 void MCStreamer::emitDwarfLineStartLabel(MCSymbol *StartSym) {
1038   // Set the value of the symbol, as we are at the start of the line table.
1039   emitLabel(StartSym);
1040 }
1041
1042 void MCStreamer::emitAssignment(MCSymbol *Symbol, const MCExpr *Value) {
1043   visitUsedExpr(*Value);
1044   Symbol->setVariableValue(Value);
1045
1046   MCTargetStreamer *TS = getTargetStreamer();
1047   if (TS)
1048     TS->emitAssignment(Symbol, Value);
1049 }
1050
1051 void MCTargetStreamer::prettyPrintAsm(MCInstPrinter &InstPrinter,
1052                                       uint64_t Address, const MCInst &Inst,
1053                                       const MCSubtargetInfo &STI,
1054                                       raw_ostream &OS) {
1055   InstPrinter.printInst(&Inst, Address, "", STI, OS);
1056 }
1057
1058 void MCStreamer::visitUsedSymbol(const MCSymbol &Sym) {
1059 }
1060
1061 void MCStreamer::visitUsedExpr(const MCExpr &Expr) {
1062   switch (Expr.getKind()) {
1063   case MCExpr::Target:
1064     cast<MCTargetExpr>(Expr).visitUsedExpr(*this);
1065     break;
1066
1067   case MCExpr::Constant:
1068     break;
1069
1070   case MCExpr::Binary: {
1071     const MCBinaryExpr &BE = cast<MCBinaryExpr>(Expr);
1072     visitUsedExpr(*BE.getLHS());
1073     visitUsedExpr(*BE.getRHS());
1074     break;
1075   }
1076
1077   case MCExpr::SymbolRef:
1078     visitUsedSymbol(cast<MCSymbolRefExpr>(Expr).getSymbol());
1079     break;
1080
1081   case MCExpr::Unary:
1082     visitUsedExpr(*cast<MCUnaryExpr>(Expr).getSubExpr());
1083     break;
1084   }
1085 }
1086
1087 void MCStreamer::emitInstruction(const MCInst &Inst, const MCSubtargetInfo &) {
1088   // Scan for values.
1089   for (unsigned i = Inst.getNumOperands(); i--;)
1090     if (Inst.getOperand(i).isExpr())
1091       visitUsedExpr(*Inst.getOperand(i).getExpr());
1092 }
1093
1094 void MCStreamer::emitPseudoProbe(uint64_t Guid, uint64_t Index, uint64_t Type,
1095                                  uint64_t Attr,
1096                                  const MCPseudoProbeInlineStack &InlineStack) {
1097   auto &Context = getContext();
1098
1099   // Create a symbol at in the current section for use in the probe.
1100   MCSymbol *ProbeSym = Context.createTempSymbol();
1101
1102   // Set the value of the symbol to use for the MCPseudoProbe.
1103   emitLabel(ProbeSym);
1104
1105   // Create a (local) probe entry with the symbol.
1106   MCPseudoProbe Probe(ProbeSym, Guid, Index, Type, Attr);
1107
1108   // Add the probe entry to this section's entries.
1109   Context.getMCPseudoProbeTable().getProbeSections().addPseudoProbe(
1110       getCurrentSectionOnly(), Probe, InlineStack);
1111 }
1112
1113 void MCStreamer::emitAbsoluteSymbolDiff(const MCSymbol *Hi, const MCSymbol *Lo,
1114                                         unsigned Size) {
1115   // Get the Hi-Lo expression.
1116   const MCExpr *Diff =
1117       MCBinaryExpr::createSub(MCSymbolRefExpr::create(Hi, Context),
1118                               MCSymbolRefExpr::create(Lo, Context), Context);
1119
1120   const MCAsmInfo *MAI = Context.getAsmInfo();
1121   if (!MAI->doesSetDirectiveSuppressReloc()) {
1122     emitValue(Diff, Size);
1123     return;
1124   }
1125
1126   // Otherwise, emit with .set (aka assignment).
1127   MCSymbol *SetLabel = Context.createTempSymbol("set");
1128   emitAssignment(SetLabel, Diff);
1129   emitSymbolValue(SetLabel, Size);
1130 }
1131
1132 void MCStreamer::emitAbsoluteSymbolDiffAsULEB128(const MCSymbol *Hi,
1133                                                  const MCSymbol *Lo) {
1134   // Get the Hi-Lo expression.
1135   const MCExpr *Diff =
1136       MCBinaryExpr::createSub(MCSymbolRefExpr::create(Hi, Context),
1137                               MCSymbolRefExpr::create(Lo, Context), Context);
1138
1139   emitULEB128Value(Diff);
1140 }
1141
1142 void MCStreamer::emitAssemblerFlag(MCAssemblerFlag Flag) {}
1143 void MCStreamer::emitThumbFunc(MCSymbol *Func) {}
1144 void MCStreamer::emitSymbolDesc(MCSymbol *Symbol, unsigned DescValue) {}
1145 void MCStreamer::BeginCOFFSymbolDef(const MCSymbol *Symbol) {
1146   llvm_unreachable("this directive only supported on COFF targets");
1147 }
1148 void MCStreamer::EndCOFFSymbolDef() {
1149   llvm_unreachable("this directive only supported on COFF targets");
1150 }
1151 void MCStreamer::emitFileDirective(StringRef Filename) {}
1152 void MCStreamer::emitFileDirective(StringRef Filename, StringRef CompilerVerion,
1153                                    StringRef TimeStamp, StringRef Description) {
1154 }
1155 void MCStreamer::EmitCOFFSymbolStorageClass(int StorageClass) {
1156   llvm_unreachable("this directive only supported on COFF targets");
1157 }
1158 void MCStreamer::EmitCOFFSymbolType(int Type) {
1159   llvm_unreachable("this directive only supported on COFF targets");
1160 }
1161 void MCStreamer::emitXCOFFLocalCommonSymbol(MCSymbol *LabelSym, uint64_t Size,
1162                                             MCSymbol *CsectSym,
1163                                             unsigned ByteAlign) {
1164   llvm_unreachable("this directive only supported on XCOFF targets");
1165 }
1166
1167 void MCStreamer::emitXCOFFSymbolLinkageWithVisibility(MCSymbol *Symbol,
1168                                                       MCSymbolAttr Linkage,
1169                                                       MCSymbolAttr Visibility) {
1170   llvm_unreachable("emitXCOFFSymbolLinkageWithVisibility is only supported on "
1171                    "XCOFF targets");
1172 }
1173
1174 void MCStreamer::emitXCOFFRenameDirective(const MCSymbol *Name,
1175                                           StringRef Rename) {
1176   llvm_unreachable("emitXCOFFRenameDirective is only supported on "
1177                    "XCOFF targets");
1178 }
1179
1180 void MCStreamer::emitELFSize(MCSymbol *Symbol, const MCExpr *Value) {}
1181 void MCStreamer::emitELFSymverDirective(const MCSymbol *OriginalSym,
1182                                         StringRef Name, bool KeepOriginalSym) {}
1183 void MCStreamer::emitLocalCommonSymbol(MCSymbol *Symbol, uint64_t Size,
1184                                        unsigned ByteAlignment) {}
1185 void MCStreamer::emitTBSSSymbol(MCSection *Section, MCSymbol *Symbol,
1186                                 uint64_t Size, unsigned ByteAlignment) {}
1187 void MCStreamer::changeSection(MCSection *, const MCExpr *) {}
1188 void MCStreamer::emitWeakReference(MCSymbol *Alias, const MCSymbol *Symbol) {}
1189 void MCStreamer::emitBytes(StringRef Data) {}
1190 void MCStreamer::emitBinaryData(StringRef Data) { emitBytes(Data); }
1191 void MCStreamer::emitValueImpl(const MCExpr *Value, unsigned Size, SMLoc Loc) {
1192   visitUsedExpr(*Value);
1193 }
1194 void MCStreamer::emitULEB128Value(const MCExpr *Value) {}
1195 void MCStreamer::emitSLEB128Value(const MCExpr *Value) {}
1196 void MCStreamer::emitFill(const MCExpr &NumBytes, uint64_t Value, SMLoc Loc) {}
1197 void MCStreamer::emitFill(const MCExpr &NumValues, int64_t Size, int64_t Expr,
1198                           SMLoc Loc) {}
1199 void MCStreamer::emitValueToAlignment(unsigned ByteAlignment, int64_t Value,
1200                                       unsigned ValueSize,
1201                                       unsigned MaxBytesToEmit) {}
1202 void MCStreamer::emitCodeAlignment(unsigned ByteAlignment,
1203                                    const MCSubtargetInfo *STI,
1204                                    unsigned MaxBytesToEmit) {}
1205 void MCStreamer::emitValueToOffset(const MCExpr *Offset, unsigned char Value,
1206                                    SMLoc Loc) {}
1207 void MCStreamer::emitBundleAlignMode(unsigned AlignPow2) {}
1208 void MCStreamer::emitBundleLock(bool AlignToEnd) {}
1209 void MCStreamer::finishImpl() {}
1210 void MCStreamer::emitBundleUnlock() {}
1211
1212 void MCStreamer::SwitchSection(MCSection *Section, const MCExpr *Subsection) {
1213   assert(Section && "Cannot switch to a null section!");
1214   MCSectionSubPair curSection = SectionStack.back().first;
1215   SectionStack.back().second = curSection;
1216   if (MCSectionSubPair(Section, Subsection) != curSection) {
1217     changeSection(Section, Subsection);
1218     SectionStack.back().first = MCSectionSubPair(Section, Subsection);
1219     assert(!Section->hasEnded() && "Section already ended");
1220     MCSymbol *Sym = Section->getBeginSymbol();
1221     if (Sym && !Sym->isInSection())
1222       emitLabel(Sym);
1223   }
1224 }
1225
1226 MCSymbol *MCStreamer::endSection(MCSection *Section) {
1227   // TODO: keep track of the last subsection so that this symbol appears in the
1228   // correct place.
1229   MCSymbol *Sym = Section->getEndSymbol(Context);
1230   if (Sym->isInSection())
1231     return Sym;
1232
1233   SwitchSection(Section);
1234   emitLabel(Sym);
1235   return Sym;
1236 }
1237
1238 static VersionTuple
1239 targetVersionOrMinimumSupportedOSVersion(const Triple &Target,
1240                                          VersionTuple TargetVersion) {
1241   VersionTuple Min = Target.getMinimumSupportedOSVersion();
1242   return !Min.empty() && Min > TargetVersion ? Min : TargetVersion;
1243 }
1244
1245 static MCVersionMinType
1246 getMachoVersionMinLoadCommandType(const Triple &Target) {
1247   assert(Target.isOSDarwin() && "expected a darwin OS");
1248   switch (Target.getOS()) {
1249   case Triple::MacOSX:
1250   case Triple::Darwin:
1251     return MCVM_OSXVersionMin;
1252   case Triple::IOS:
1253     assert(!Target.isMacCatalystEnvironment() &&
1254            "mac Catalyst should use LC_BUILD_VERSION");
1255     return MCVM_IOSVersionMin;
1256   case Triple::TvOS:
1257     return MCVM_TvOSVersionMin;
1258   case Triple::WatchOS:
1259     return MCVM_WatchOSVersionMin;
1260   default:
1261     break;
1262   }
1263   llvm_unreachable("unexpected OS type");
1264 }
1265
1266 static VersionTuple getMachoBuildVersionSupportedOS(const Triple &Target) {
1267   assert(Target.isOSDarwin() && "expected a darwin OS");
1268   switch (Target.getOS()) {
1269   case Triple::MacOSX:
1270   case Triple::Darwin:
1271     return VersionTuple(10, 14);
1272   case Triple::IOS:
1273     // Mac Catalyst always uses the build version load command.
1274     if (Target.isMacCatalystEnvironment())
1275       return VersionTuple();
1276     LLVM_FALLTHROUGH;
1277   case Triple::TvOS:
1278     return VersionTuple(12);
1279   case Triple::WatchOS:
1280     return VersionTuple(5);
1281   default:
1282     break;
1283   }
1284   llvm_unreachable("unexpected OS type");
1285 }
1286
1287 static MachO::PlatformType
1288 getMachoBuildVersionPlatformType(const Triple &Target) {
1289   assert(Target.isOSDarwin() && "expected a darwin OS");
1290   switch (Target.getOS()) {
1291   case Triple::MacOSX:
1292   case Triple::Darwin:
1293     return MachO::PLATFORM_MACOS;
1294   case Triple::IOS:
1295     if (Target.isMacCatalystEnvironment())
1296       return MachO::PLATFORM_MACCATALYST;
1297     return Target.isSimulatorEnvironment() ? MachO::PLATFORM_IOSSIMULATOR
1298                                            : MachO::PLATFORM_IOS;
1299   case Triple::TvOS:
1300     return Target.isSimulatorEnvironment() ? MachO::PLATFORM_TVOSSIMULATOR
1301                                            : MachO::PLATFORM_TVOS;
1302   case Triple::WatchOS:
1303     return Target.isSimulatorEnvironment() ? MachO::PLATFORM_WATCHOSSIMULATOR
1304                                            : MachO::PLATFORM_WATCHOS;
1305   default:
1306     break;
1307   }
1308   llvm_unreachable("unexpected OS type");
1309 }
1310
1311 void MCStreamer::emitVersionForTarget(const Triple &Target,
1312                                       const VersionTuple &SDKVersion) {
1313   if (!Target.isOSBinFormatMachO() || !Target.isOSDarwin())
1314     return;
1315   // Do we even know the version?
1316   if (Target.getOSMajorVersion() == 0)
1317     return;
1318
1319   unsigned Major = 0;
1320   unsigned Minor = 0;
1321   unsigned Update = 0;
1322   switch (Target.getOS()) {
1323   case Triple::MacOSX:
1324   case Triple::Darwin:
1325     Target.getMacOSXVersion(Major, Minor, Update);
1326     break;
1327   case Triple::IOS:
1328   case Triple::TvOS:
1329     Target.getiOSVersion(Major, Minor, Update);
1330     break;
1331   case Triple::WatchOS:
1332     Target.getWatchOSVersion(Major, Minor, Update);
1333     break;
1334   default:
1335     llvm_unreachable("unexpected OS type");
1336   }
1337   assert(Major != 0 && "A non-zero major version is expected");
1338   auto LinkedTargetVersion = targetVersionOrMinimumSupportedOSVersion(
1339       Target, VersionTuple(Major, Minor, Update));
1340   auto BuildVersionOSVersion = getMachoBuildVersionSupportedOS(Target);
1341   if (BuildVersionOSVersion.empty() ||
1342       LinkedTargetVersion >= BuildVersionOSVersion)
1343     return emitBuildVersion(getMachoBuildVersionPlatformType(Target),
1344                             LinkedTargetVersion.getMajor(),
1345                             *LinkedTargetVersion.getMinor(),
1346                             *LinkedTargetVersion.getSubminor(), SDKVersion);
1347
1348   emitVersionMin(getMachoVersionMinLoadCommandType(Target),
1349                  LinkedTargetVersion.getMajor(),
1350                  *LinkedTargetVersion.getMinor(),
1351                  *LinkedTargetVersion.getSubminor(), SDKVersion);
1352 }