1 //===- MCContext.h - Machine Code Context -----------------------*- C++ -*-===// 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 #ifndef LLVM_MC_MCCONTEXT_H 11 #define LLVM_MC_MCCONTEXT_H 12 13 #include "llvm/ADT/DenseMap.h" 14 #include "llvm/ADT/SetVector.h" 15 #include "llvm/ADT/SmallString.h" 16 #include "llvm/ADT/SmallVector.h" 17 #include "llvm/ADT/StringMap.h" 18 #include "llvm/ADT/StringRef.h" 19 #include "llvm/ADT/Twine.h" 20 #include "llvm/BinaryFormat/Dwarf.h" 21 #include "llvm/MC/MCDwarf.h" 22 #include "llvm/MC/MCSubtargetInfo.h" 23 #include "llvm/MC/SectionKind.h" 24 #include "llvm/Support/Allocator.h" 25 #include "llvm/Support/Compiler.h" 26 #include "llvm/Support/raw_ostream.h" 27 #include <algorithm> 28 #include <cassert> 29 #include <cstddef> 30 #include <cstdint> 31 #include <map> 32 #include <memory> 33 #include <string> 34 #include <utility> 35 #include <vector> 36 37 namespace llvm { 38 39 class CodeViewContext; 40 class MCAsmInfo; 41 class MCLabel; 42 class MCObjectFileInfo; 43 class MCRegisterInfo; 44 class MCSection; 45 class MCSectionCOFF; 46 class MCSectionELF; 47 class MCSectionMachO; 48 class MCSectionWasm; 49 class MCStreamer; 50 class MCSymbol; 51 class MCSymbolELF; 52 class MCSymbolWasm; 53 class SMLoc; 54 class SourceMgr; 55 56 /// Context object for machine code objects. This class owns all of the 57 /// sections that it creates. 58 /// 59 class MCContext { 60 public: 61 using SymbolTable = StringMap<MCSymbol *, BumpPtrAllocator &>; 62 63 private: 64 /// The SourceMgr for this object, if any. 65 const SourceMgr *SrcMgr; 66 67 /// The SourceMgr for inline assembly, if any. 68 SourceMgr *InlineSrcMgr; 69 70 /// The MCAsmInfo for this target. 71 const MCAsmInfo *MAI; 72 73 /// The MCRegisterInfo for this target. 74 const MCRegisterInfo *MRI; 75 76 /// The MCObjectFileInfo for this target. 77 const MCObjectFileInfo *MOFI; 78 79 std::unique_ptr<CodeViewContext> CVContext; 80 81 /// Allocator object used for creating machine code objects. 82 /// 83 /// We use a bump pointer allocator to avoid the need to track all allocated 84 /// objects. 85 BumpPtrAllocator Allocator; 86 87 SpecificBumpPtrAllocator<MCSectionCOFF> COFFAllocator; 88 SpecificBumpPtrAllocator<MCSectionELF> ELFAllocator; 89 SpecificBumpPtrAllocator<MCSectionMachO> MachOAllocator; 90 SpecificBumpPtrAllocator<MCSectionWasm> WasmAllocator; 91 92 /// Bindings of names to symbols. 93 SymbolTable Symbols; 94 95 /// A mapping from a local label number and an instance count to a symbol. 96 /// For example, in the assembly 97 /// 1: 98 /// 2: 99 /// 1: 100 /// We have three labels represented by the pairs (1, 0), (2, 0) and (1, 1) 101 DenseMap<std::pair<unsigned, unsigned>, MCSymbol *> LocalSymbols; 102 103 /// Keeps tracks of names that were used both for used declared and 104 /// artificial symbols. The value is "true" if the name has been used for a 105 /// non-section symbol (there can be at most one of those, plus an unlimited 106 /// number of section symbols with the same name). 107 StringMap<bool, BumpPtrAllocator &> UsedNames; 108 109 /// The next ID to dole out to an unnamed assembler temporary symbol with 110 /// a given prefix. 111 StringMap<unsigned> NextID; 112 113 /// Instances of directional local labels. 114 DenseMap<unsigned, MCLabel *> Instances; 115 /// NextInstance() creates the next instance of the directional local label 116 /// for the LocalLabelVal and adds it to the map if needed. 117 unsigned NextInstance(unsigned LocalLabelVal); 118 /// GetInstance() gets the current instance of the directional local label 119 /// for the LocalLabelVal and adds it to the map if needed. 120 unsigned GetInstance(unsigned LocalLabelVal); 121 122 /// The file name of the log file from the environment variable 123 /// AS_SECURE_LOG_FILE. Which must be set before the .secure_log_unique 124 /// directive is used or it is an error. 125 char *SecureLogFile; 126 /// The stream that gets written to for the .secure_log_unique directive. 127 std::unique_ptr<raw_fd_ostream> SecureLog; 128 /// Boolean toggled when .secure_log_unique / .secure_log_reset is seen to 129 /// catch errors if .secure_log_unique appears twice without 130 /// .secure_log_reset appearing between them. 131 bool SecureLogUsed = false; 132 133 /// The compilation directory to use for DW_AT_comp_dir. 134 SmallString<128> CompilationDir; 135 136 /// The main file name if passed in explicitly. 137 std::string MainFileName; 138 139 /// The dwarf file and directory tables from the dwarf .file directive. 140 /// We now emit a line table for each compile unit. To reduce the prologue 141 /// size of each line table, the files and directories used by each compile 142 /// unit are separated. 143 std::map<unsigned, MCDwarfLineTable> MCDwarfLineTablesCUMap; 144 145 /// The current dwarf line information from the last dwarf .loc directive. 146 MCDwarfLoc CurrentDwarfLoc; 147 bool DwarfLocSeen = false; 148 149 /// Generate dwarf debugging info for assembly source files. 150 bool GenDwarfForAssembly = false; 151 152 /// The current dwarf file number when generate dwarf debugging info for 153 /// assembly source files. 154 unsigned GenDwarfFileNumber = 0; 155 156 /// Sections for generating the .debug_ranges and .debug_aranges sections. 157 SetVector<MCSection *> SectionsForRanges; 158 159 /// The information gathered from labels that will have dwarf label 160 /// entries when generating dwarf assembly source files. 161 std::vector<MCGenDwarfLabelEntry> MCGenDwarfLabelEntries; 162 163 /// The string to embed in the debug information for the compile unit, if 164 /// non-empty. 165 StringRef DwarfDebugFlags; 166 167 /// The string to embed in as the dwarf AT_producer for the compile unit, if 168 /// non-empty. 169 StringRef DwarfDebugProducer; 170 171 /// The maximum version of dwarf that we should emit. 172 uint16_t DwarfVersion = 4; 173 174 /// Honor temporary labels, this is useful for debugging semantic 175 /// differences between temporary and non-temporary labels (primarily on 176 /// Darwin). 177 bool AllowTemporaryLabels = true; 178 bool UseNamesOnTempLabels = true; 179 180 /// The Compile Unit ID that we are currently processing. 181 unsigned DwarfCompileUnitID = 0; 182 183 struct ELFSectionKey { 184 std::string SectionName; 185 StringRef GroupName; 186 unsigned UniqueID; 187 188 ELFSectionKey(StringRef SectionName, StringRef GroupName, 189 unsigned UniqueID) 190 : SectionName(SectionName), GroupName(GroupName), UniqueID(UniqueID) { 191 } 192 193 bool operator<(const ELFSectionKey &Other) const { 194 if (SectionName != Other.SectionName) 195 return SectionName < Other.SectionName; 196 if (GroupName != Other.GroupName) 197 return GroupName < Other.GroupName; 198 return UniqueID < Other.UniqueID; 199 } 200 }; 201 202 struct COFFSectionKey { 203 std::string SectionName; 204 StringRef GroupName; 205 int SelectionKey; 206 unsigned UniqueID; 207 208 COFFSectionKey(StringRef SectionName, StringRef GroupName, 209 int SelectionKey, unsigned UniqueID) 210 : SectionName(SectionName), GroupName(GroupName), 211 SelectionKey(SelectionKey), UniqueID(UniqueID) {} 212 213 bool operator<(const COFFSectionKey &Other) const { 214 if (SectionName != Other.SectionName) 215 return SectionName < Other.SectionName; 216 if (GroupName != Other.GroupName) 217 return GroupName < Other.GroupName; 218 if (SelectionKey != Other.SelectionKey) 219 return SelectionKey < Other.SelectionKey; 220 return UniqueID < Other.UniqueID; 221 } 222 }; 223 224 struct WasmSectionKey { 225 std::string SectionName; 226 StringRef GroupName; 227 unsigned UniqueID; 228 229 WasmSectionKey(StringRef SectionName, StringRef GroupName, 230 unsigned UniqueID) 231 : SectionName(SectionName), GroupName(GroupName), UniqueID(UniqueID) { 232 } 233 234 bool operator<(const WasmSectionKey &Other) const { 235 if (SectionName != Other.SectionName) 236 return SectionName < Other.SectionName; 237 if (GroupName != Other.GroupName) 238 return GroupName < Other.GroupName; 239 return UniqueID < Other.UniqueID; 240 } 241 }; 242 243 StringMap<MCSectionMachO *> MachOUniquingMap; 244 std::map<ELFSectionKey, MCSectionELF *> ELFUniquingMap; 245 std::map<COFFSectionKey, MCSectionCOFF *> COFFUniquingMap; 246 std::map<WasmSectionKey, MCSectionWasm *> WasmUniquingMap; 247 StringMap<bool> RelSecNames; 248 249 SpecificBumpPtrAllocator<MCSubtargetInfo> MCSubtargetAllocator; 250 251 /// Do automatic reset in destructor 252 bool AutoReset; 253 254 bool HadError = false; 255 256 MCSymbol *createSymbolImpl(const StringMapEntry<bool> *Name, 257 bool CanBeUnnamed); 258 MCSymbol *createSymbol(StringRef Name, bool AlwaysAddSuffix, 259 bool IsTemporary); 260 261 MCSymbol *getOrCreateDirectionalLocalSymbol(unsigned LocalLabelVal, 262 unsigned Instance); 263 264 MCSectionELF *createELFSectionImpl(StringRef Section, unsigned Type, 265 unsigned Flags, SectionKind K, 266 unsigned EntrySize, 267 const MCSymbolELF *Group, 268 unsigned UniqueID, 269 const MCSymbolELF *Associated); 270 271 public: 272 explicit MCContext(const MCAsmInfo *MAI, const MCRegisterInfo *MRI, 273 const MCObjectFileInfo *MOFI, 274 const SourceMgr *Mgr = nullptr, bool DoAutoReset = true); 275 MCContext(const MCContext &) = delete; 276 MCContext &operator=(const MCContext &) = delete; 277 ~MCContext(); 278 279 const SourceMgr *getSourceManager() const { return SrcMgr; } 280 281 void setInlineSourceManager(SourceMgr *SM) { InlineSrcMgr = SM; } 282 283 const MCAsmInfo *getAsmInfo() const { return MAI; } 284 285 const MCRegisterInfo *getRegisterInfo() const { return MRI; } 286 287 const MCObjectFileInfo *getObjectFileInfo() const { return MOFI; } 288 289 CodeViewContext &getCVContext(); 290 291 void setAllowTemporaryLabels(bool Value) { AllowTemporaryLabels = Value; } 292 void setUseNamesOnTempLabels(bool Value) { UseNamesOnTempLabels = Value; } 293 294 /// \name Module Lifetime Management 295 /// @{ 296 297 /// reset - return object to right after construction state to prepare 298 /// to process a new module 299 void reset(); 300 301 /// @} 302 303 /// \name Symbol Management 304 /// @{ 305 306 /// Create and return a new linker temporary symbol with a unique but 307 /// unspecified name. 308 MCSymbol *createLinkerPrivateTempSymbol(); 309 310 /// Create and return a new assembler temporary symbol with a unique but 311 /// unspecified name. 312 MCSymbol *createTempSymbol(bool CanBeUnnamed = true); 313 314 MCSymbol *createTempSymbol(const Twine &Name, bool AlwaysAddSuffix, 315 bool CanBeUnnamed = true); 316 317 /// Create the definition of a directional local symbol for numbered label 318 /// (used for "1:" definitions). 319 MCSymbol *createDirectionalLocalSymbol(unsigned LocalLabelVal); 320 321 /// Create and return a directional local symbol for numbered label (used 322 /// for "1b" or 1f" references). 323 MCSymbol *getDirectionalLocalSymbol(unsigned LocalLabelVal, bool Before); 324 325 /// Lookup the symbol inside with the specified \p Name. If it exists, 326 /// return it. If not, create a forward reference and return it. 327 /// 328 /// \param Name - The symbol name, which must be unique across all symbols. 329 MCSymbol *getOrCreateSymbol(const Twine &Name); 330 331 /// Gets a symbol that will be defined to the final stack offset of a local 332 /// variable after codegen. 333 /// 334 /// \param Idx - The index of a local variable passed to @llvm.localescape. 335 MCSymbol *getOrCreateFrameAllocSymbol(StringRef FuncName, unsigned Idx); 336 337 MCSymbol *getOrCreateParentFrameOffsetSymbol(StringRef FuncName); 338 339 MCSymbol *getOrCreateLSDASymbol(StringRef FuncName); 340 341 /// Get the symbol for \p Name, or null. 342 MCSymbol *lookupSymbol(const Twine &Name) const; 343 344 /// Set value for a symbol. 345 void setSymbolValue(MCStreamer &Streamer, StringRef Sym, uint64_t Val); 346 347 /// getSymbols - Get a reference for the symbol table for clients that 348 /// want to, for example, iterate over all symbols. 'const' because we 349 /// still want any modifications to the table itself to use the MCContext 350 /// APIs. 351 const SymbolTable &getSymbols() const { return Symbols; } 352 353 /// @} 354 355 /// \name Section Management 356 /// @{ 357 358 enum : unsigned { 359 /// Pass this value as the UniqueID during section creation to get the 360 /// generic section with the given name and characteristics. The usual 361 /// sections such as .text use this ID. 362 GenericSectionID = ~0U 363 }; 364 365 /// Return the MCSection for the specified mach-o section. This requires 366 /// the operands to be valid. 367 MCSectionMachO *getMachOSection(StringRef Segment, StringRef Section, 368 unsigned TypeAndAttributes, 369 unsigned Reserved2, SectionKind K, 370 const char *BeginSymName = nullptr); 371 372 MCSectionMachO *getMachOSection(StringRef Segment, StringRef Section, 373 unsigned TypeAndAttributes, SectionKind K, 374 const char *BeginSymName = nullptr) { 375 return getMachOSection(Segment, Section, TypeAndAttributes, 0, K, 376 BeginSymName); 377 } 378 379 MCSectionELF *getELFSection(const Twine &Section, unsigned Type, 380 unsigned Flags) { 381 return getELFSection(Section, Type, Flags, 0, ""); 382 } 383 384 MCSectionELF *getELFSection(const Twine &Section, unsigned Type, 385 unsigned Flags, unsigned EntrySize, 386 const Twine &Group) { 387 return getELFSection(Section, Type, Flags, EntrySize, Group, ~0); 388 } 389 390 MCSectionELF *getELFSection(const Twine &Section, unsigned Type, 391 unsigned Flags, unsigned EntrySize, 392 const Twine &Group, unsigned UniqueID) { 393 return getELFSection(Section, Type, Flags, EntrySize, Group, UniqueID, 394 nullptr); 395 } 396 397 MCSectionELF *getELFSection(const Twine &Section, unsigned Type, 398 unsigned Flags, unsigned EntrySize, 399 const Twine &Group, unsigned UniqueID, 400 const MCSymbolELF *Associated); 401 402 MCSectionELF *getELFSection(const Twine &Section, unsigned Type, 403 unsigned Flags, unsigned EntrySize, 404 const MCSymbolELF *Group, unsigned UniqueID, 405 const MCSymbolELF *Associated); 406 407 /// Get a section with the provided group identifier. This section is 408 /// named by concatenating \p Prefix with '.' then \p Suffix. The \p Type 409 /// describes the type of the section and \p Flags are used to further 410 /// configure this named section. 411 MCSectionELF *getELFNamedSection(const Twine &Prefix, const Twine &Suffix, 412 unsigned Type, unsigned Flags, 413 unsigned EntrySize = 0); 414 415 MCSectionELF *createELFRelSection(const Twine &Name, unsigned Type, 416 unsigned Flags, unsigned EntrySize, 417 const MCSymbolELF *Group, 418 const MCSectionELF *RelInfoSection); 419 420 void renameELFSection(MCSectionELF *Section, StringRef Name); 421 422 MCSectionELF *createELFGroupSection(const MCSymbolELF *Group); 423 424 MCSectionCOFF *getCOFFSection(StringRef Section, unsigned Characteristics, 425 SectionKind Kind, StringRef COMDATSymName, 426 int Selection, 427 unsigned UniqueID = GenericSectionID, 428 const char *BeginSymName = nullptr); 429 430 MCSectionCOFF *getCOFFSection(StringRef Section, unsigned Characteristics, 431 SectionKind Kind, 432 const char *BeginSymName = nullptr); 433 434 MCSectionCOFF *getCOFFSection(StringRef Section); 435 436 /// Gets or creates a section equivalent to Sec that is associated with the 437 /// section containing KeySym. For example, to create a debug info section 438 /// associated with an inline function, pass the normal debug info section 439 /// as Sec and the function symbol as KeySym. 440 MCSectionCOFF * 441 getAssociativeCOFFSection(MCSectionCOFF *Sec, const MCSymbol *KeySym, 442 unsigned UniqueID = GenericSectionID); 443 444 MCSectionWasm *getWasmSection(const Twine &Section, unsigned Type) { 445 return getWasmSection(Section, Type, nullptr); 446 } 447 448 MCSectionWasm *getWasmSection(const Twine &Section, unsigned Type, 449 const char *BeginSymName) { 450 return getWasmSection(Section, Type, "", ~0, BeginSymName); 451 } 452 453 MCSectionWasm *getWasmSection(const Twine &Section, unsigned Type, 454 const Twine &Group, unsigned UniqueID) { 455 return getWasmSection(Section, Type, Group, UniqueID, nullptr); 456 } 457 458 MCSectionWasm *getWasmSection(const Twine &Section, unsigned Type, 459 const Twine &Group, unsigned UniqueID, 460 const char *BeginSymName); 461 462 MCSectionWasm *getWasmSection(const Twine &Section, unsigned Type, 463 const MCSymbolWasm *Group, unsigned UniqueID, 464 const char *BeginSymName); 465 466 // Create and save a copy of STI and return a reference to the copy. 467 MCSubtargetInfo &getSubtargetCopy(const MCSubtargetInfo &STI); 468 469 /// @} 470 471 /// \name Dwarf Management 472 /// @{ 473 474 /// \brief Get the compilation directory for DW_AT_comp_dir 475 /// The compilation directory should be set with \c setCompilationDir before 476 /// calling this function. If it is unset, an empty string will be returned. 477 StringRef getCompilationDir() const { return CompilationDir; } 478 479 /// \brief Set the compilation directory for DW_AT_comp_dir 480 void setCompilationDir(StringRef S) { CompilationDir = S.str(); } 481 482 /// \brief Get the main file name for use in error messages and debug 483 /// info. This can be set to ensure we've got the correct file name 484 /// after preprocessing or for -save-temps. 485 const std::string &getMainFileName() const { return MainFileName; } 486 487 /// \brief Set the main file name and override the default. 488 void setMainFileName(StringRef S) { MainFileName = S; } 489 490 /// Creates an entry in the dwarf file and directory tables. 491 unsigned getDwarfFile(StringRef Directory, StringRef FileName, 492 unsigned FileNumber, unsigned CUID); 493 494 bool isValidDwarfFileNumber(unsigned FileNumber, unsigned CUID = 0); 495 496 const std::map<unsigned, MCDwarfLineTable> &getMCDwarfLineTables() const { 497 return MCDwarfLineTablesCUMap; 498 } 499 500 MCDwarfLineTable &getMCDwarfLineTable(unsigned CUID) { 501 return MCDwarfLineTablesCUMap[CUID]; 502 } 503 504 const MCDwarfLineTable &getMCDwarfLineTable(unsigned CUID) const { 505 auto I = MCDwarfLineTablesCUMap.find(CUID); 506 assert(I != MCDwarfLineTablesCUMap.end()); 507 return I->second; 508 } 509 510 const SmallVectorImpl<MCDwarfFile> &getMCDwarfFiles(unsigned CUID = 0) { 511 return getMCDwarfLineTable(CUID).getMCDwarfFiles(); 512 } 513 514 const SmallVectorImpl<std::string> &getMCDwarfDirs(unsigned CUID = 0) { 515 return getMCDwarfLineTable(CUID).getMCDwarfDirs(); 516 } 517 518 bool hasMCLineSections() const { 519 for (const auto &Table : MCDwarfLineTablesCUMap) 520 if (!Table.second.getMCDwarfFiles().empty() || Table.second.getLabel()) 521 return true; 522 return false; 523 } 524 525 unsigned getDwarfCompileUnitID() { return DwarfCompileUnitID; } 526 527 void setDwarfCompileUnitID(unsigned CUIndex) { 528 DwarfCompileUnitID = CUIndex; 529 } 530 531 void setMCLineTableCompilationDir(unsigned CUID, StringRef CompilationDir) { 532 getMCDwarfLineTable(CUID).setCompilationDir(CompilationDir); 533 } 534 535 /// Saves the information from the currently parsed dwarf .loc directive 536 /// and sets DwarfLocSeen. When the next instruction is assembled an entry 537 /// in the line number table with this information and the address of the 538 /// instruction will be created. 539 void setCurrentDwarfLoc(unsigned FileNum, unsigned Line, unsigned Column, 540 unsigned Flags, unsigned Isa, 541 unsigned Discriminator) { 542 CurrentDwarfLoc.setFileNum(FileNum); 543 CurrentDwarfLoc.setLine(Line); 544 CurrentDwarfLoc.setColumn(Column); 545 CurrentDwarfLoc.setFlags(Flags); 546 CurrentDwarfLoc.setIsa(Isa); 547 CurrentDwarfLoc.setDiscriminator(Discriminator); 548 DwarfLocSeen = true; 549 } 550 551 void clearDwarfLocSeen() { DwarfLocSeen = false; } 552 553 bool getDwarfLocSeen() { return DwarfLocSeen; } 554 const MCDwarfLoc &getCurrentDwarfLoc() { return CurrentDwarfLoc; } 555 556 bool getGenDwarfForAssembly() { return GenDwarfForAssembly; } 557 void setGenDwarfForAssembly(bool Value) { GenDwarfForAssembly = Value; } 558 unsigned getGenDwarfFileNumber() { return GenDwarfFileNumber; } 559 560 void setGenDwarfFileNumber(unsigned FileNumber) { 561 GenDwarfFileNumber = FileNumber; 562 } 563 564 const SetVector<MCSection *> &getGenDwarfSectionSyms() { 565 return SectionsForRanges; 566 } 567 568 bool addGenDwarfSection(MCSection *Sec) { 569 return SectionsForRanges.insert(Sec); 570 } 571 572 void finalizeDwarfSections(MCStreamer &MCOS); 573 574 const std::vector<MCGenDwarfLabelEntry> &getMCGenDwarfLabelEntries() const { 575 return MCGenDwarfLabelEntries; 576 } 577 578 void addMCGenDwarfLabelEntry(const MCGenDwarfLabelEntry &E) { 579 MCGenDwarfLabelEntries.push_back(E); 580 } 581 582 void setDwarfDebugFlags(StringRef S) { DwarfDebugFlags = S; } 583 StringRef getDwarfDebugFlags() { return DwarfDebugFlags; } 584 585 void setDwarfDebugProducer(StringRef S) { DwarfDebugProducer = S; } 586 StringRef getDwarfDebugProducer() { return DwarfDebugProducer; } 587 588 dwarf::DwarfFormat getDwarfFormat() const { 589 // TODO: Support DWARF64 590 return dwarf::DWARF32; 591 } 592 593 void setDwarfVersion(uint16_t v) { DwarfVersion = v; } 594 uint16_t getDwarfVersion() const { return DwarfVersion; } 595 596 /// @} 597 598 char *getSecureLogFile() { return SecureLogFile; } 599 raw_fd_ostream *getSecureLog() { return SecureLog.get(); } 600 601 void setSecureLog(std::unique_ptr<raw_fd_ostream> Value) { 602 SecureLog = std::move(Value); 603 } 604 605 bool getSecureLogUsed() { return SecureLogUsed; } 606 void setSecureLogUsed(bool Value) { SecureLogUsed = Value; } 607 608 void *allocate(unsigned Size, unsigned Align = 8) { 609 return Allocator.Allocate(Size, Align); 610 } 611 612 void deallocate(void *Ptr) {} 613 614 bool hadError() { return HadError; } 615 void reportError(SMLoc L, const Twine &Msg); 616 // Unrecoverable error has occurred. Display the best diagnostic we can 617 // and bail via exit(1). For now, most MC backend errors are unrecoverable. 618 // FIXME: We should really do something about that. 619 LLVM_ATTRIBUTE_NORETURN void reportFatalError(SMLoc L, 620 const Twine &Msg); 621 }; 622 623 } // end namespace llvm 624 625 // operator new and delete aren't allowed inside namespaces. 626 // The throw specifications are mandated by the standard. 627 /// \brief Placement new for using the MCContext's allocator. 628 /// 629 /// This placement form of operator new uses the MCContext's allocator for 630 /// obtaining memory. It is a non-throwing new, which means that it returns 631 /// null on error. (If that is what the allocator does. The current does, so if 632 /// this ever changes, this operator will have to be changed, too.) 633 /// Usage looks like this (assuming there's an MCContext 'Context' in scope): 634 /// \code 635 /// // Default alignment (8) 636 /// IntegerLiteral *Ex = new (Context) IntegerLiteral(arguments); 637 /// // Specific alignment 638 /// IntegerLiteral *Ex2 = new (Context, 4) IntegerLiteral(arguments); 639 /// \endcode 640 /// Please note that you cannot use delete on the pointer; it must be 641 /// deallocated using an explicit destructor call followed by 642 /// \c Context.Deallocate(Ptr). 643 /// 644 /// \param Bytes The number of bytes to allocate. Calculated by the compiler. 645 /// \param C The MCContext that provides the allocator. 646 /// \param Alignment The alignment of the allocated memory (if the underlying 647 /// allocator supports it). 648 /// \return The allocated memory. Could be NULL. 649 inline void *operator new(size_t Bytes, llvm::MCContext &C, 650 size_t Alignment = 8) noexcept { 651 return C.allocate(Bytes, Alignment); 652 } 653 /// \brief Placement delete companion to the new above. 654 /// 655 /// This operator is just a companion to the new above. There is no way of 656 /// invoking it directly; see the new operator for more details. This operator 657 /// is called implicitly by the compiler if a placement new expression using 658 /// the MCContext throws in the object constructor. 659 inline void operator delete(void *Ptr, llvm::MCContext &C, size_t) noexcept { 660 C.deallocate(Ptr); 661 } 662 663 /// This placement form of operator new[] uses the MCContext's allocator for 664 /// obtaining memory. It is a non-throwing new[], which means that it returns 665 /// null on error. 666 /// Usage looks like this (assuming there's an MCContext 'Context' in scope): 667 /// \code 668 /// // Default alignment (8) 669 /// char *data = new (Context) char[10]; 670 /// // Specific alignment 671 /// char *data = new (Context, 4) char[10]; 672 /// \endcode 673 /// Please note that you cannot use delete on the pointer; it must be 674 /// deallocated using an explicit destructor call followed by 675 /// \c Context.Deallocate(Ptr). 676 /// 677 /// \param Bytes The number of bytes to allocate. Calculated by the compiler. 678 /// \param C The MCContext that provides the allocator. 679 /// \param Alignment The alignment of the allocated memory (if the underlying 680 /// allocator supports it). 681 /// \return The allocated memory. Could be NULL. 682 inline void *operator new[](size_t Bytes, llvm::MCContext &C, 683 size_t Alignment = 8) noexcept { 684 return C.allocate(Bytes, Alignment); 685 } 686 687 /// \brief Placement delete[] companion to the new[] above. 688 /// 689 /// This operator is just a companion to the new[] above. There is no way of 690 /// invoking it directly; see the new[] operator for more details. This operator 691 /// is called implicitly by the compiler if a placement new[] expression using 692 /// the MCContext throws in the object constructor. 693 inline void operator delete[](void *Ptr, llvm::MCContext &C) noexcept { 694 C.deallocate(Ptr); 695 } 696 697 #endif // LLVM_MC_MCCONTEXT_H 698