1 //===- MCContext.h - Machine Code Context -----------------------*- C++ -*-===//
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 #ifndef LLVM_MC_MCCONTEXT_H
10 #define LLVM_MC_MCCONTEXT_H
11 
12 #include "llvm/ADT/DenseMap.h"
13 #include "llvm/ADT/SetVector.h"
14 #include "llvm/ADT/SmallString.h"
15 #include "llvm/ADT/StringMap.h"
16 #include "llvm/ADT/StringRef.h"
17 #include "llvm/ADT/Twine.h"
18 #include "llvm/BinaryFormat/Dwarf.h"
19 #include "llvm/BinaryFormat/XCOFF.h"
20 #include "llvm/MC/MCAsmMacro.h"
21 #include "llvm/MC/MCDwarf.h"
22 #include "llvm/MC/MCPseudoProbe.h"
23 #include "llvm/MC/MCSection.h"
24 #include "llvm/MC/SectionKind.h"
25 #include "llvm/Support/Allocator.h"
26 #include "llvm/Support/Compiler.h"
27 #include "llvm/Support/Error.h"
28 #include "llvm/Support/MD5.h"
29 #include "llvm/Support/raw_ostream.h"
30 #include <algorithm>
31 #include <cassert>
32 #include <cstddef>
33 #include <cstdint>
34 #include <functional>
35 #include <map>
36 #include <memory>
37 #include <optional>
38 #include <string>
39 #include <utility>
40 #include <vector>
41 
42 namespace llvm {
43 
44 class CodeViewContext;
45 class MCAsmInfo;
46 class MCInst;
47 class MCLabel;
48 class MCObjectFileInfo;
49 class MCRegisterInfo;
50 class MCSection;
51 class MCSectionCOFF;
52 class MCSectionDXContainer;
53 class MCSectionELF;
54 class MCSectionGOFF;
55 class MCSectionMachO;
56 class MCSectionSPIRV;
57 class MCSectionWasm;
58 class MCSectionXCOFF;
59 class MCStreamer;
60 class MCSubtargetInfo;
61 class MCSymbol;
62 class MCSymbolELF;
63 class MCSymbolWasm;
64 class MCSymbolXCOFF;
65 class MCTargetOptions;
66 class MDNode;
67 template <typename T> class SmallVectorImpl;
68 class SMDiagnostic;
69 class SMLoc;
70 class SourceMgr;
71 enum class EmitDwarfUnwindType;
72 
73 /// Context object for machine code objects.  This class owns all of the
74 /// sections that it creates.
75 ///
76 class MCContext {
77 public:
78   using SymbolTable = StringMap<MCSymbol *, BumpPtrAllocator &>;
79   using DiagHandlerTy =
80       std::function<void(const SMDiagnostic &, bool, const SourceMgr &,
81                          std::vector<const MDNode *> &)>;
82   enum Environment {
83     IsMachO,
84     IsELF,
85     IsGOFF,
86     IsCOFF,
87     IsSPIRV,
88     IsWasm,
89     IsXCOFF,
90     IsDXContainer
91   };
92 
93 private:
94   Environment Env;
95 
96   /// The name of the Segment where Swift5 Reflection Section data will be
97   /// outputted
98   StringRef Swift5ReflectionSegmentName;
99 
100   /// The triple for this object.
101   Triple TT;
102 
103   /// The SourceMgr for this object, if any.
104   const SourceMgr *SrcMgr;
105 
106   /// The SourceMgr for inline assembly, if any.
107   std::unique_ptr<SourceMgr> InlineSrcMgr;
108   std::vector<const MDNode *> LocInfos;
109 
110   DiagHandlerTy DiagHandler;
111 
112   /// The MCAsmInfo for this target.
113   const MCAsmInfo *MAI;
114 
115   /// The MCRegisterInfo for this target.
116   const MCRegisterInfo *MRI;
117 
118   /// The MCObjectFileInfo for this target.
119   const MCObjectFileInfo *MOFI;
120 
121   /// The MCSubtargetInfo for this target.
122   const MCSubtargetInfo *MSTI;
123 
124   std::unique_ptr<CodeViewContext> CVContext;
125 
126   /// Allocator object used for creating machine code objects.
127   ///
128   /// We use a bump pointer allocator to avoid the need to track all allocated
129   /// objects.
130   BumpPtrAllocator Allocator;
131 
132   SpecificBumpPtrAllocator<MCSectionCOFF> COFFAllocator;
133   SpecificBumpPtrAllocator<MCSectionDXContainer> DXCAllocator;
134   SpecificBumpPtrAllocator<MCSectionELF> ELFAllocator;
135   SpecificBumpPtrAllocator<MCSectionMachO> MachOAllocator;
136   SpecificBumpPtrAllocator<MCSectionGOFF> GOFFAllocator;
137   SpecificBumpPtrAllocator<MCSectionSPIRV> SPIRVAllocator;
138   SpecificBumpPtrAllocator<MCSectionWasm> WasmAllocator;
139   SpecificBumpPtrAllocator<MCSectionXCOFF> XCOFFAllocator;
140   SpecificBumpPtrAllocator<MCInst> MCInstAllocator;
141 
142   /// Bindings of names to symbols.
143   SymbolTable Symbols;
144 
145   /// A mapping from a local label number and an instance count to a symbol.
146   /// For example, in the assembly
147   ///     1:
148   ///     2:
149   ///     1:
150   /// We have three labels represented by the pairs (1, 0), (2, 0) and (1, 1)
151   DenseMap<std::pair<unsigned, unsigned>, MCSymbol *> LocalSymbols;
152 
153   /// Keeps tracks of names that were used both for used declared and
154   /// artificial symbols. The value is "true" if the name has been used for a
155   /// non-section symbol (there can be at most one of those, plus an unlimited
156   /// number of section symbols with the same name).
157   StringMap<bool, BumpPtrAllocator &> UsedNames;
158 
159   /// Keeps track of labels that are used in inline assembly.
160   SymbolTable InlineAsmUsedLabelNames;
161 
162   /// The next ID to dole out to an unnamed assembler temporary symbol with
163   /// a given prefix.
164   StringMap<unsigned> NextID;
165 
166   /// Instances of directional local labels.
167   DenseMap<unsigned, MCLabel *> Instances;
168   /// NextInstance() creates the next instance of the directional local label
169   /// for the LocalLabelVal and adds it to the map if needed.
170   unsigned NextInstance(unsigned LocalLabelVal);
171   /// GetInstance() gets the current instance of the directional local label
172   /// for the LocalLabelVal and adds it to the map if needed.
173   unsigned GetInstance(unsigned LocalLabelVal);
174 
175   /// LLVM_BB_ADDR_MAP version to emit.
176   uint8_t BBAddrMapVersion = 1;
177 
178   /// The file name of the log file from the environment variable
179   /// AS_SECURE_LOG_FILE.  Which must be set before the .secure_log_unique
180   /// directive is used or it is an error.
181   std::string SecureLogFile;
182   /// The stream that gets written to for the .secure_log_unique directive.
183   std::unique_ptr<raw_fd_ostream> SecureLog;
184   /// Boolean toggled when .secure_log_unique / .secure_log_reset is seen to
185   /// catch errors if .secure_log_unique appears twice without
186   /// .secure_log_reset appearing between them.
187   bool SecureLogUsed = false;
188 
189   /// The compilation directory to use for DW_AT_comp_dir.
190   SmallString<128> CompilationDir;
191 
192   /// Prefix replacement map for source file information.
193   std::map<std::string, const std::string, std::greater<>> DebugPrefixMap;
194 
195   /// The main file name if passed in explicitly.
196   std::string MainFileName;
197 
198   /// The dwarf file and directory tables from the dwarf .file directive.
199   /// We now emit a line table for each compile unit. To reduce the prologue
200   /// size of each line table, the files and directories used by each compile
201   /// unit are separated.
202   std::map<unsigned, MCDwarfLineTable> MCDwarfLineTablesCUMap;
203 
204   /// The current dwarf line information from the last dwarf .loc directive.
205   MCDwarfLoc CurrentDwarfLoc;
206   bool DwarfLocSeen = false;
207 
208   /// Generate dwarf debugging info for assembly source files.
209   bool GenDwarfForAssembly = false;
210 
211   /// The current dwarf file number when generate dwarf debugging info for
212   /// assembly source files.
213   unsigned GenDwarfFileNumber = 0;
214 
215   /// Sections for generating the .debug_ranges and .debug_aranges sections.
216   SetVector<MCSection *> SectionsForRanges;
217 
218   /// The information gathered from labels that will have dwarf label
219   /// entries when generating dwarf assembly source files.
220   std::vector<MCGenDwarfLabelEntry> MCGenDwarfLabelEntries;
221 
222   /// The string to embed in the debug information for the compile unit, if
223   /// non-empty.
224   StringRef DwarfDebugFlags;
225 
226   /// The string to embed in as the dwarf AT_producer for the compile unit, if
227   /// non-empty.
228   StringRef DwarfDebugProducer;
229 
230   /// The maximum version of dwarf that we should emit.
231   uint16_t DwarfVersion = 4;
232 
233   /// The format of dwarf that we emit.
234   dwarf::DwarfFormat DwarfFormat = dwarf::DWARF32;
235 
236   /// Honor temporary labels, this is useful for debugging semantic
237   /// differences between temporary and non-temporary labels (primarily on
238   /// Darwin).
239   bool AllowTemporaryLabels = true;
240   bool UseNamesOnTempLabels = false;
241 
242   /// The Compile Unit ID that we are currently processing.
243   unsigned DwarfCompileUnitID = 0;
244 
245   /// A collection of MCPseudoProbe in the current module
246   MCPseudoProbeTable PseudoProbeTable;
247 
248   // Sections are differentiated by the quadruple (section_name, group_name,
249   // unique_id, link_to_symbol_name). Sections sharing the same quadruple are
250   // combined into one section.
251   struct ELFSectionKey {
252     std::string SectionName;
253     StringRef GroupName;
254     StringRef LinkedToName;
255     unsigned UniqueID;
256 
257     ELFSectionKey(StringRef SectionName, StringRef GroupName,
258                   StringRef LinkedToName, unsigned UniqueID)
259         : SectionName(SectionName), GroupName(GroupName),
260           LinkedToName(LinkedToName), UniqueID(UniqueID) {}
261 
262     bool operator<(const ELFSectionKey &Other) const {
263       if (SectionName != Other.SectionName)
264         return SectionName < Other.SectionName;
265       if (GroupName != Other.GroupName)
266         return GroupName < Other.GroupName;
267       if (int O = LinkedToName.compare(Other.LinkedToName))
268         return O < 0;
269       return UniqueID < Other.UniqueID;
270     }
271   };
272 
273   struct COFFSectionKey {
274     std::string SectionName;
275     StringRef GroupName;
276     int SelectionKey;
277     unsigned UniqueID;
278 
279     COFFSectionKey(StringRef SectionName, StringRef GroupName, int SelectionKey,
280                    unsigned UniqueID)
281         : SectionName(SectionName), GroupName(GroupName),
282           SelectionKey(SelectionKey), UniqueID(UniqueID) {}
283 
284     bool operator<(const COFFSectionKey &Other) const {
285       if (SectionName != Other.SectionName)
286         return SectionName < Other.SectionName;
287       if (GroupName != Other.GroupName)
288         return GroupName < Other.GroupName;
289       if (SelectionKey != Other.SelectionKey)
290         return SelectionKey < Other.SelectionKey;
291       return UniqueID < Other.UniqueID;
292     }
293   };
294 
295   struct WasmSectionKey {
296     std::string SectionName;
297     StringRef GroupName;
298     unsigned UniqueID;
299 
300     WasmSectionKey(StringRef SectionName, StringRef GroupName,
301                    unsigned UniqueID)
302         : SectionName(SectionName), GroupName(GroupName), UniqueID(UniqueID) {}
303 
304     bool operator<(const WasmSectionKey &Other) const {
305       if (SectionName != Other.SectionName)
306         return SectionName < Other.SectionName;
307       if (GroupName != Other.GroupName)
308         return GroupName < Other.GroupName;
309       return UniqueID < Other.UniqueID;
310     }
311   };
312 
313   struct XCOFFSectionKey {
314     // Section name.
315     std::string SectionName;
316     // Section property.
317     // For csect section, it is storage mapping class.
318     // For debug section, it is section type flags.
319     union {
320       XCOFF::StorageMappingClass MappingClass;
321       XCOFF::DwarfSectionSubtypeFlags DwarfSubtypeFlags;
322     };
323     bool IsCsect;
324 
325     XCOFFSectionKey(StringRef SectionName,
326                     XCOFF::StorageMappingClass MappingClass)
327         : SectionName(SectionName), MappingClass(MappingClass), IsCsect(true) {}
328 
329     XCOFFSectionKey(StringRef SectionName,
330                     XCOFF::DwarfSectionSubtypeFlags DwarfSubtypeFlags)
331         : SectionName(SectionName), DwarfSubtypeFlags(DwarfSubtypeFlags),
332           IsCsect(false) {}
333 
334     bool operator<(const XCOFFSectionKey &Other) const {
335       if (IsCsect && Other.IsCsect)
336         return std::tie(SectionName, MappingClass) <
337                std::tie(Other.SectionName, Other.MappingClass);
338       if (IsCsect != Other.IsCsect)
339         return IsCsect;
340       return std::tie(SectionName, DwarfSubtypeFlags) <
341              std::tie(Other.SectionName, Other.DwarfSubtypeFlags);
342     }
343   };
344 
345   StringMap<MCSectionMachO *> MachOUniquingMap;
346   std::map<ELFSectionKey, MCSectionELF *> ELFUniquingMap;
347   std::map<COFFSectionKey, MCSectionCOFF *> COFFUniquingMap;
348   std::map<std::string, MCSectionGOFF *> GOFFUniquingMap;
349   std::map<WasmSectionKey, MCSectionWasm *> WasmUniquingMap;
350   std::map<XCOFFSectionKey, MCSectionXCOFF *> XCOFFUniquingMap;
351   StringMap<MCSectionDXContainer *> DXCUniquingMap;
352   StringMap<bool> RelSecNames;
353 
354   SpecificBumpPtrAllocator<MCSubtargetInfo> MCSubtargetAllocator;
355 
356   /// Do automatic reset in destructor
357   bool AutoReset;
358 
359   MCTargetOptions const *TargetOptions;
360 
361   bool HadError = false;
362 
363   void reportCommon(SMLoc Loc,
364                     std::function<void(SMDiagnostic &, const SourceMgr *)>);
365 
366   MCSymbol *createSymbolImpl(const StringMapEntry<bool> *Name,
367                              bool CanBeUnnamed);
368   MCSymbol *createSymbol(StringRef Name, bool AlwaysAddSuffix,
369                          bool IsTemporary);
370 
371   MCSymbol *getOrCreateDirectionalLocalSymbol(unsigned LocalLabelVal,
372                                               unsigned Instance);
373 
374   MCSectionELF *createELFSectionImpl(StringRef Section, unsigned Type,
375                                      unsigned Flags, SectionKind K,
376                                      unsigned EntrySize,
377                                      const MCSymbolELF *Group, bool IsComdat,
378                                      unsigned UniqueID,
379                                      const MCSymbolELF *LinkedToSym);
380 
381   MCSymbolXCOFF *createXCOFFSymbolImpl(const StringMapEntry<bool> *Name,
382                                        bool IsTemporary);
383 
384   /// Map of currently defined macros.
385   StringMap<MCAsmMacro> MacroMap;
386 
387   struct ELFEntrySizeKey {
388     std::string SectionName;
389     unsigned Flags;
390     unsigned EntrySize;
391 
392     ELFEntrySizeKey(StringRef SectionName, unsigned Flags, unsigned EntrySize)
393         : SectionName(SectionName), Flags(Flags), EntrySize(EntrySize) {}
394 
395     bool operator<(const ELFEntrySizeKey &Other) const {
396       if (SectionName != Other.SectionName)
397         return SectionName < Other.SectionName;
398       if (Flags != Other.Flags)
399         return Flags < Other.Flags;
400       return EntrySize < Other.EntrySize;
401     }
402   };
403 
404   // Symbols must be assigned to a section with a compatible entry size and
405   // flags. This map is used to assign unique IDs to sections to distinguish
406   // between sections with identical names but incompatible entry sizes and/or
407   // flags. This can occur when a symbol is explicitly assigned to a section,
408   // e.g. via __attribute__((section("myname"))).
409   std::map<ELFEntrySizeKey, unsigned> ELFEntrySizeMap;
410 
411   // This set is used to record the generic mergeable section names seen.
412   // These are sections that are created as mergeable e.g. .debug_str. We need
413   // to avoid assigning non-mergeable symbols to these sections. It is used
414   // to prevent non-mergeable symbols being explicitly assigned  to mergeable
415   // sections (e.g. via _attribute_((section("myname")))).
416   DenseSet<StringRef> ELFSeenGenericMergeableSections;
417 
418 public:
419   explicit MCContext(const Triple &TheTriple, const MCAsmInfo *MAI,
420                      const MCRegisterInfo *MRI, const MCSubtargetInfo *MSTI,
421                      const SourceMgr *Mgr = nullptr,
422                      MCTargetOptions const *TargetOpts = nullptr,
423                      bool DoAutoReset = true,
424                      StringRef Swift5ReflSegmentName = {});
425   MCContext(const MCContext &) = delete;
426   MCContext &operator=(const MCContext &) = delete;
427   ~MCContext();
428 
429   Environment getObjectFileType() const { return Env; }
430 
431   const StringRef &getSwift5ReflectionSegmentName() const {
432     return Swift5ReflectionSegmentName;
433   }
434   const Triple &getTargetTriple() const { return TT; }
435   const SourceMgr *getSourceManager() const { return SrcMgr; }
436 
437   void initInlineSourceManager();
438   SourceMgr *getInlineSourceManager() { return InlineSrcMgr.get(); }
439   std::vector<const MDNode *> &getLocInfos() { return LocInfos; }
440   void setDiagnosticHandler(DiagHandlerTy DiagHandler) {
441     this->DiagHandler = DiagHandler;
442   }
443 
444   void setObjectFileInfo(const MCObjectFileInfo *Mofi) { MOFI = Mofi; }
445 
446   const MCAsmInfo *getAsmInfo() const { return MAI; }
447 
448   const MCRegisterInfo *getRegisterInfo() const { return MRI; }
449 
450   const MCObjectFileInfo *getObjectFileInfo() const { return MOFI; }
451 
452   const MCSubtargetInfo *getSubtargetInfo() const { return MSTI; }
453 
454   CodeViewContext &getCVContext();
455 
456   void setAllowTemporaryLabels(bool Value) { AllowTemporaryLabels = Value; }
457   void setUseNamesOnTempLabels(bool Value) { UseNamesOnTempLabels = Value; }
458 
459   /// \name Module Lifetime Management
460   /// @{
461 
462   /// reset - return object to right after construction state to prepare
463   /// to process a new module
464   void reset();
465 
466   /// @}
467 
468   /// \name McInst Management
469 
470   /// Create and return a new MC instruction.
471   MCInst *createMCInst();
472 
473   /// \name Symbol Management
474   /// @{
475 
476   /// Create and return a new linker temporary symbol with a unique but
477   /// unspecified name.
478   MCSymbol *createLinkerPrivateTempSymbol();
479 
480   /// Create a temporary symbol with a unique name. The name will be omitted
481   /// in the symbol table if UseNamesOnTempLabels is false (default except
482   /// MCAsmStreamer). The overload without Name uses an unspecified name.
483   MCSymbol *createTempSymbol();
484   MCSymbol *createTempSymbol(const Twine &Name, bool AlwaysAddSuffix = true);
485 
486   /// Create a temporary symbol with a unique name whose name cannot be
487   /// omitted in the symbol table. This is rarely used.
488   MCSymbol *createNamedTempSymbol();
489   MCSymbol *createNamedTempSymbol(const Twine &Name);
490 
491   /// Create the definition of a directional local symbol for numbered label
492   /// (used for "1:" definitions).
493   MCSymbol *createDirectionalLocalSymbol(unsigned LocalLabelVal);
494 
495   /// Create and return a directional local symbol for numbered label (used
496   /// for "1b" or 1f" references).
497   MCSymbol *getDirectionalLocalSymbol(unsigned LocalLabelVal, bool Before);
498 
499   /// Lookup the symbol inside with the specified \p Name.  If it exists,
500   /// return it.  If not, create a forward reference and return it.
501   ///
502   /// \param Name - The symbol name, which must be unique across all symbols.
503   MCSymbol *getOrCreateSymbol(const Twine &Name);
504 
505   /// Gets a symbol that will be defined to the final stack offset of a local
506   /// variable after codegen.
507   ///
508   /// \param Idx - The index of a local variable passed to \@llvm.localescape.
509   MCSymbol *getOrCreateFrameAllocSymbol(StringRef FuncName, unsigned Idx);
510 
511   MCSymbol *getOrCreateParentFrameOffsetSymbol(StringRef FuncName);
512 
513   MCSymbol *getOrCreateLSDASymbol(StringRef FuncName);
514 
515   /// Get the symbol for \p Name, or null.
516   MCSymbol *lookupSymbol(const Twine &Name) const;
517 
518   /// Set value for a symbol.
519   void setSymbolValue(MCStreamer &Streamer, StringRef Sym, uint64_t Val);
520 
521   /// getSymbols - Get a reference for the symbol table for clients that
522   /// want to, for example, iterate over all symbols. 'const' because we
523   /// still want any modifications to the table itself to use the MCContext
524   /// APIs.
525   const SymbolTable &getSymbols() const { return Symbols; }
526 
527   /// isInlineAsmLabel - Return true if the name is a label referenced in
528   /// inline assembly.
529   MCSymbol *getInlineAsmLabel(StringRef Name) const {
530     return InlineAsmUsedLabelNames.lookup(Name);
531   }
532 
533   /// registerInlineAsmLabel - Records that the name is a label referenced in
534   /// inline assembly.
535   void registerInlineAsmLabel(MCSymbol *Sym);
536 
537   /// @}
538 
539   /// \name Section Management
540   /// @{
541 
542   enum : unsigned {
543     /// Pass this value as the UniqueID during section creation to get the
544     /// generic section with the given name and characteristics. The usual
545     /// sections such as .text use this ID.
546     GenericSectionID = ~0U
547   };
548 
549   /// Return the MCSection for the specified mach-o section.  This requires
550   /// the operands to be valid.
551   MCSectionMachO *getMachOSection(StringRef Segment, StringRef Section,
552                                   unsigned TypeAndAttributes,
553                                   unsigned Reserved2, SectionKind K,
554                                   const char *BeginSymName = nullptr);
555 
556   MCSectionMachO *getMachOSection(StringRef Segment, StringRef Section,
557                                   unsigned TypeAndAttributes, SectionKind K,
558                                   const char *BeginSymName = nullptr) {
559     return getMachOSection(Segment, Section, TypeAndAttributes, 0, K,
560                            BeginSymName);
561   }
562 
563   MCSectionELF *getELFSection(const Twine &Section, unsigned Type,
564                               unsigned Flags) {
565     return getELFSection(Section, Type, Flags, 0, "", false);
566   }
567 
568   MCSectionELF *getELFSection(const Twine &Section, unsigned Type,
569                               unsigned Flags, unsigned EntrySize) {
570     return getELFSection(Section, Type, Flags, EntrySize, "", false,
571                          MCSection::NonUniqueID, nullptr);
572   }
573 
574   MCSectionELF *getELFSection(const Twine &Section, unsigned Type,
575                               unsigned Flags, unsigned EntrySize,
576                               const Twine &Group, bool IsComdat) {
577     return getELFSection(Section, Type, Flags, EntrySize, Group, IsComdat,
578                          MCSection::NonUniqueID, nullptr);
579   }
580 
581   MCSectionELF *getELFSection(const Twine &Section, unsigned Type,
582                               unsigned Flags, unsigned EntrySize,
583                               const Twine &Group, bool IsComdat,
584                               unsigned UniqueID,
585                               const MCSymbolELF *LinkedToSym);
586 
587   MCSectionELF *getELFSection(const Twine &Section, unsigned Type,
588                               unsigned Flags, unsigned EntrySize,
589                               const MCSymbolELF *Group, bool IsComdat,
590                               unsigned UniqueID,
591                               const MCSymbolELF *LinkedToSym);
592 
593   /// Get a section with the provided group identifier. This section is
594   /// named by concatenating \p Prefix with '.' then \p Suffix. The \p Type
595   /// describes the type of the section and \p Flags are used to further
596   /// configure this named section.
597   MCSectionELF *getELFNamedSection(const Twine &Prefix, const Twine &Suffix,
598                                    unsigned Type, unsigned Flags,
599                                    unsigned EntrySize = 0);
600 
601   MCSectionELF *createELFRelSection(const Twine &Name, unsigned Type,
602                                     unsigned Flags, unsigned EntrySize,
603                                     const MCSymbolELF *Group,
604                                     const MCSectionELF *RelInfoSection);
605 
606   MCSectionELF *createELFGroupSection(const MCSymbolELF *Group, bool IsComdat);
607 
608   void recordELFMergeableSectionInfo(StringRef SectionName, unsigned Flags,
609                                      unsigned UniqueID, unsigned EntrySize);
610 
611   bool isELFImplicitMergeableSectionNamePrefix(StringRef Name);
612 
613   bool isELFGenericMergeableSection(StringRef Name);
614 
615   /// Return the unique ID of the section with the given name, flags and entry
616   /// size, if it exists.
617   std::optional<unsigned> getELFUniqueIDForEntsize(StringRef SectionName,
618                                                    unsigned Flags,
619                                                    unsigned EntrySize);
620 
621   MCSectionGOFF *getGOFFSection(StringRef Section, SectionKind Kind,
622                                 MCSection *Parent, const MCExpr *SubsectionId);
623 
624   MCSectionCOFF *getCOFFSection(StringRef Section, unsigned Characteristics,
625                                 SectionKind Kind, StringRef COMDATSymName,
626                                 int Selection,
627                                 unsigned UniqueID = GenericSectionID,
628                                 const char *BeginSymName = nullptr);
629 
630   MCSectionCOFF *getCOFFSection(StringRef Section, unsigned Characteristics,
631                                 SectionKind Kind,
632                                 const char *BeginSymName = nullptr);
633 
634   /// Gets or creates a section equivalent to Sec that is associated with the
635   /// section containing KeySym. For example, to create a debug info section
636   /// associated with an inline function, pass the normal debug info section
637   /// as Sec and the function symbol as KeySym.
638   MCSectionCOFF *
639   getAssociativeCOFFSection(MCSectionCOFF *Sec, const MCSymbol *KeySym,
640                             unsigned UniqueID = GenericSectionID);
641 
642   MCSectionSPIRV *getSPIRVSection();
643 
644   MCSectionWasm *getWasmSection(const Twine &Section, SectionKind K,
645                                 unsigned Flags = 0) {
646     return getWasmSection(Section, K, Flags, nullptr);
647   }
648 
649   MCSectionWasm *getWasmSection(const Twine &Section, SectionKind K,
650                                 unsigned Flags, const char *BeginSymName) {
651     return getWasmSection(Section, K, Flags, "", ~0, BeginSymName);
652   }
653 
654   MCSectionWasm *getWasmSection(const Twine &Section, SectionKind K,
655                                 unsigned Flags, const Twine &Group,
656                                 unsigned UniqueID) {
657     return getWasmSection(Section, K, Flags, Group, UniqueID, nullptr);
658   }
659 
660   MCSectionWasm *getWasmSection(const Twine &Section, SectionKind K,
661                                 unsigned Flags, const Twine &Group,
662                                 unsigned UniqueID, const char *BeginSymName);
663 
664   MCSectionWasm *getWasmSection(const Twine &Section, SectionKind K,
665                                 unsigned Flags, const MCSymbolWasm *Group,
666                                 unsigned UniqueID, const char *BeginSymName);
667 
668   /// Get the section for the provided Section name
669   MCSectionDXContainer *getDXContainerSection(StringRef Section, SectionKind K);
670 
671   bool hasXCOFFSection(StringRef Section,
672                        XCOFF::CsectProperties CsectProp) const;
673 
674   MCSectionXCOFF *getXCOFFSection(
675       StringRef Section, SectionKind K,
676       std::optional<XCOFF::CsectProperties> CsectProp = std::nullopt,
677       bool MultiSymbolsAllowed = false, const char *BeginSymName = nullptr,
678       std::optional<XCOFF::DwarfSectionSubtypeFlags> DwarfSubtypeFlags =
679           std::nullopt);
680 
681   // Create and save a copy of STI and return a reference to the copy.
682   MCSubtargetInfo &getSubtargetCopy(const MCSubtargetInfo &STI);
683 
684   uint8_t getBBAddrMapVersion() const { return BBAddrMapVersion; }
685 
686   /// @}
687 
688   /// \name Dwarf Management
689   /// @{
690 
691   /// Get the compilation directory for DW_AT_comp_dir
692   /// The compilation directory should be set with \c setCompilationDir before
693   /// calling this function. If it is unset, an empty string will be returned.
694   StringRef getCompilationDir() const { return CompilationDir; }
695 
696   /// Set the compilation directory for DW_AT_comp_dir
697   void setCompilationDir(StringRef S) { CompilationDir = S.str(); }
698 
699   /// Add an entry to the debug prefix map.
700   void addDebugPrefixMapEntry(const std::string &From, const std::string &To);
701 
702   /// Remap one path in-place as per the debug prefix map.
703   void remapDebugPath(SmallVectorImpl<char> &Path);
704 
705   // Remaps all debug directory paths in-place as per the debug prefix map.
706   void RemapDebugPaths();
707 
708   /// Get the main file name for use in error messages and debug
709   /// info. This can be set to ensure we've got the correct file name
710   /// after preprocessing or for -save-temps.
711   const std::string &getMainFileName() const { return MainFileName; }
712 
713   /// Set the main file name and override the default.
714   void setMainFileName(StringRef S) { MainFileName = std::string(S); }
715 
716   /// Creates an entry in the dwarf file and directory tables.
717   Expected<unsigned> getDwarfFile(StringRef Directory, StringRef FileName,
718                                   unsigned FileNumber,
719                                   std::optional<MD5::MD5Result> Checksum,
720                                   std::optional<StringRef> Source,
721                                   unsigned CUID);
722 
723   bool isValidDwarfFileNumber(unsigned FileNumber, unsigned CUID = 0);
724 
725   const std::map<unsigned, MCDwarfLineTable> &getMCDwarfLineTables() const {
726     return MCDwarfLineTablesCUMap;
727   }
728 
729   MCDwarfLineTable &getMCDwarfLineTable(unsigned CUID) {
730     return MCDwarfLineTablesCUMap[CUID];
731   }
732 
733   const MCDwarfLineTable &getMCDwarfLineTable(unsigned CUID) const {
734     auto I = MCDwarfLineTablesCUMap.find(CUID);
735     assert(I != MCDwarfLineTablesCUMap.end());
736     return I->second;
737   }
738 
739   const SmallVectorImpl<MCDwarfFile> &getMCDwarfFiles(unsigned CUID = 0) {
740     return getMCDwarfLineTable(CUID).getMCDwarfFiles();
741   }
742 
743   const SmallVectorImpl<std::string> &getMCDwarfDirs(unsigned CUID = 0) {
744     return getMCDwarfLineTable(CUID).getMCDwarfDirs();
745   }
746 
747   unsigned getDwarfCompileUnitID() { return DwarfCompileUnitID; }
748 
749   void setDwarfCompileUnitID(unsigned CUIndex) { DwarfCompileUnitID = CUIndex; }
750 
751   /// Specifies the "root" file and directory of the compilation unit.
752   /// These are "file 0" and "directory 0" in DWARF v5.
753   void setMCLineTableRootFile(unsigned CUID, StringRef CompilationDir,
754                               StringRef Filename,
755                               std::optional<MD5::MD5Result> Checksum,
756                               std::optional<StringRef> Source) {
757     getMCDwarfLineTable(CUID).setRootFile(CompilationDir, Filename, Checksum,
758                                           Source);
759   }
760 
761   /// Reports whether MD5 checksum usage is consistent (all-or-none).
762   bool isDwarfMD5UsageConsistent(unsigned CUID) const {
763     return getMCDwarfLineTable(CUID).isMD5UsageConsistent();
764   }
765 
766   /// Saves the information from the currently parsed dwarf .loc directive
767   /// and sets DwarfLocSeen.  When the next instruction is assembled an entry
768   /// in the line number table with this information and the address of the
769   /// instruction will be created.
770   void setCurrentDwarfLoc(unsigned FileNum, unsigned Line, unsigned Column,
771                           unsigned Flags, unsigned Isa,
772                           unsigned Discriminator) {
773     CurrentDwarfLoc.setFileNum(FileNum);
774     CurrentDwarfLoc.setLine(Line);
775     CurrentDwarfLoc.setColumn(Column);
776     CurrentDwarfLoc.setFlags(Flags);
777     CurrentDwarfLoc.setIsa(Isa);
778     CurrentDwarfLoc.setDiscriminator(Discriminator);
779     DwarfLocSeen = true;
780   }
781 
782   void clearDwarfLocSeen() { DwarfLocSeen = false; }
783 
784   bool getDwarfLocSeen() { return DwarfLocSeen; }
785   const MCDwarfLoc &getCurrentDwarfLoc() { return CurrentDwarfLoc; }
786 
787   bool getGenDwarfForAssembly() { return GenDwarfForAssembly; }
788   void setGenDwarfForAssembly(bool Value) { GenDwarfForAssembly = Value; }
789   unsigned getGenDwarfFileNumber() { return GenDwarfFileNumber; }
790   EmitDwarfUnwindType emitDwarfUnwindInfo() const;
791 
792   void setGenDwarfFileNumber(unsigned FileNumber) {
793     GenDwarfFileNumber = FileNumber;
794   }
795 
796   /// Specifies information about the "root file" for assembler clients
797   /// (e.g., llvm-mc). Assumes compilation dir etc. have been set up.
798   void setGenDwarfRootFile(StringRef FileName, StringRef Buffer);
799 
800   const SetVector<MCSection *> &getGenDwarfSectionSyms() {
801     return SectionsForRanges;
802   }
803 
804   bool addGenDwarfSection(MCSection *Sec) {
805     return SectionsForRanges.insert(Sec);
806   }
807 
808   void finalizeDwarfSections(MCStreamer &MCOS);
809 
810   const std::vector<MCGenDwarfLabelEntry> &getMCGenDwarfLabelEntries() const {
811     return MCGenDwarfLabelEntries;
812   }
813 
814   void addMCGenDwarfLabelEntry(const MCGenDwarfLabelEntry &E) {
815     MCGenDwarfLabelEntries.push_back(E);
816   }
817 
818   void setDwarfDebugFlags(StringRef S) { DwarfDebugFlags = S; }
819   StringRef getDwarfDebugFlags() { return DwarfDebugFlags; }
820 
821   void setDwarfDebugProducer(StringRef S) { DwarfDebugProducer = S; }
822   StringRef getDwarfDebugProducer() { return DwarfDebugProducer; }
823 
824   void setDwarfFormat(dwarf::DwarfFormat f) { DwarfFormat = f; }
825   dwarf::DwarfFormat getDwarfFormat() const { return DwarfFormat; }
826 
827   void setDwarfVersion(uint16_t v) { DwarfVersion = v; }
828   uint16_t getDwarfVersion() const { return DwarfVersion; }
829 
830   /// @}
831 
832   StringRef getSecureLogFile() { return SecureLogFile; }
833   raw_fd_ostream *getSecureLog() { return SecureLog.get(); }
834 
835   void setSecureLog(std::unique_ptr<raw_fd_ostream> Value) {
836     SecureLog = std::move(Value);
837   }
838 
839   bool getSecureLogUsed() { return SecureLogUsed; }
840   void setSecureLogUsed(bool Value) { SecureLogUsed = Value; }
841 
842   void *allocate(unsigned Size, unsigned Align = 8) {
843     return Allocator.Allocate(Size, Align);
844   }
845 
846   void deallocate(void *Ptr) {}
847 
848   bool hadError() { return HadError; }
849   void diagnose(const SMDiagnostic &SMD);
850   void reportError(SMLoc L, const Twine &Msg);
851   void reportWarning(SMLoc L, const Twine &Msg);
852 
853   const MCAsmMacro *lookupMacro(StringRef Name) {
854     StringMap<MCAsmMacro>::iterator I = MacroMap.find(Name);
855     return (I == MacroMap.end()) ? nullptr : &I->getValue();
856   }
857 
858   void defineMacro(StringRef Name, MCAsmMacro Macro) {
859     MacroMap.insert(std::make_pair(Name, std::move(Macro)));
860   }
861 
862   void undefineMacro(StringRef Name) { MacroMap.erase(Name); }
863 
864   MCPseudoProbeTable &getMCPseudoProbeTable() { return PseudoProbeTable; }
865 };
866 
867 } // end namespace llvm
868 
869 // operator new and delete aren't allowed inside namespaces.
870 // The throw specifications are mandated by the standard.
871 /// Placement new for using the MCContext's allocator.
872 ///
873 /// This placement form of operator new uses the MCContext's allocator for
874 /// obtaining memory. It is a non-throwing new, which means that it returns
875 /// null on error. (If that is what the allocator does. The current does, so if
876 /// this ever changes, this operator will have to be changed, too.)
877 /// Usage looks like this (assuming there's an MCContext 'Context' in scope):
878 /// \code
879 /// // Default alignment (8)
880 /// IntegerLiteral *Ex = new (Context) IntegerLiteral(arguments);
881 /// // Specific alignment
882 /// IntegerLiteral *Ex2 = new (Context, 4) IntegerLiteral(arguments);
883 /// \endcode
884 /// Please note that you cannot use delete on the pointer; it must be
885 /// deallocated using an explicit destructor call followed by
886 /// \c Context.Deallocate(Ptr).
887 ///
888 /// \param Bytes The number of bytes to allocate. Calculated by the compiler.
889 /// \param C The MCContext that provides the allocator.
890 /// \param Alignment The alignment of the allocated memory (if the underlying
891 ///                  allocator supports it).
892 /// \return The allocated memory. Could be NULL.
893 inline void *operator new(size_t Bytes, llvm::MCContext &C,
894                           size_t Alignment = 8) noexcept {
895   return C.allocate(Bytes, Alignment);
896 }
897 /// Placement delete companion to the new above.
898 ///
899 /// This operator is just a companion to the new above. There is no way of
900 /// invoking it directly; see the new operator for more details. This operator
901 /// is called implicitly by the compiler if a placement new expression using
902 /// the MCContext throws in the object constructor.
903 inline void operator delete(void *Ptr, llvm::MCContext &C, size_t) noexcept {
904   C.deallocate(Ptr);
905 }
906 
907 /// This placement form of operator new[] uses the MCContext's allocator for
908 /// obtaining memory. It is a non-throwing new[], which means that it returns
909 /// null on error.
910 /// Usage looks like this (assuming there's an MCContext 'Context' in scope):
911 /// \code
912 /// // Default alignment (8)
913 /// char *data = new (Context) char[10];
914 /// // Specific alignment
915 /// char *data = new (Context, 4) char[10];
916 /// \endcode
917 /// Please note that you cannot use delete on the pointer; it must be
918 /// deallocated using an explicit destructor call followed by
919 /// \c Context.Deallocate(Ptr).
920 ///
921 /// \param Bytes The number of bytes to allocate. Calculated by the compiler.
922 /// \param C The MCContext that provides the allocator.
923 /// \param Alignment The alignment of the allocated memory (if the underlying
924 ///                  allocator supports it).
925 /// \return The allocated memory. Could be NULL.
926 inline void *operator new[](size_t Bytes, llvm::MCContext &C,
927                             size_t Alignment = 8) noexcept {
928   return C.allocate(Bytes, Alignment);
929 }
930 
931 /// Placement delete[] companion to the new[] above.
932 ///
933 /// This operator is just a companion to the new[] above. There is no way of
934 /// invoking it directly; see the new[] operator for more details. This operator
935 /// is called implicitly by the compiler if a placement new[] expression using
936 /// the MCContext throws in the object constructor.
937 inline void operator delete[](void *Ptr, llvm::MCContext &C) noexcept {
938   C.deallocate(Ptr);
939 }
940 
941 #endif // LLVM_MC_MCCONTEXT_H
942