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 = nullptr;
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 = nullptr;
114 
115   /// The MCRegisterInfo for this target.
116   const MCRegisterInfo *MRI = nullptr;
117 
118   /// The MCObjectFileInfo for this target.
119   const MCObjectFileInfo *MOFI = nullptr;
120 
121   /// The MCSubtargetInfo for this target.
122   const MCSubtargetInfo *MSTI = nullptr;
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 = 2;
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   SmallVector<std::pair<std::string, std::string>, 0> 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 
ELFSectionKeyELFSectionKey257     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 
COFFSectionKeyCOFFSectionKey279     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 
WasmSectionKeyWasmSectionKey300     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 
XCOFFSectionKeyXCOFFSectionKey325     XCOFFSectionKey(StringRef SectionName,
326                     XCOFF::StorageMappingClass MappingClass)
327         : SectionName(SectionName), MappingClass(MappingClass), IsCsect(true) {}
328 
XCOFFSectionKeyXCOFFSectionKey329     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 
ELFEntrySizeKeyELFEntrySizeKey392     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 
getObjectFileType()429   Environment getObjectFileType() const { return Env; }
430 
getSwift5ReflectionSegmentName()431   const StringRef &getSwift5ReflectionSegmentName() const {
432     return Swift5ReflectionSegmentName;
433   }
getTargetTriple()434   const Triple &getTargetTriple() const { return TT; }
getSourceManager()435   const SourceMgr *getSourceManager() const { return SrcMgr; }
436 
437   void initInlineSourceManager();
getInlineSourceManager()438   SourceMgr *getInlineSourceManager() { return InlineSrcMgr.get(); }
getLocInfos()439   std::vector<const MDNode *> &getLocInfos() { return LocInfos; }
setDiagnosticHandler(DiagHandlerTy DiagHandler)440   void setDiagnosticHandler(DiagHandlerTy DiagHandler) {
441     this->DiagHandler = DiagHandler;
442   }
443 
setObjectFileInfo(const MCObjectFileInfo * Mofi)444   void setObjectFileInfo(const MCObjectFileInfo *Mofi) { MOFI = Mofi; }
445 
getAsmInfo()446   const MCAsmInfo *getAsmInfo() const { return MAI; }
447 
getRegisterInfo()448   const MCRegisterInfo *getRegisterInfo() const { return MRI; }
449 
getObjectFileInfo()450   const MCObjectFileInfo *getObjectFileInfo() const { return MOFI; }
451 
getSubtargetInfo()452   const MCSubtargetInfo *getSubtargetInfo() const { return MSTI; }
453 
getTargetOptions()454   const MCTargetOptions *getTargetOptions() const { return TargetOptions; }
455 
456   CodeViewContext &getCVContext();
457 
setAllowTemporaryLabels(bool Value)458   void setAllowTemporaryLabels(bool Value) { AllowTemporaryLabels = Value; }
setUseNamesOnTempLabels(bool Value)459   void setUseNamesOnTempLabels(bool Value) { UseNamesOnTempLabels = Value; }
460 
461   /// \name Module Lifetime Management
462   /// @{
463 
464   /// reset - return object to right after construction state to prepare
465   /// to process a new module
466   void reset();
467 
468   /// @}
469 
470   /// \name McInst Management
471 
472   /// Create and return a new MC instruction.
473   MCInst *createMCInst();
474 
475   /// \name Symbol Management
476   /// @{
477 
478   /// Create a new linker temporary symbol with the specified prefix (Name) or
479   /// "tmp". This creates a "l"-prefixed symbol for Mach-O and is identical to
480   /// createNamedTempSymbol for other object file formats.
481   MCSymbol *createLinkerPrivateTempSymbol();
482   MCSymbol *createLinkerPrivateSymbol(const Twine &Name);
483 
484   /// Create a temporary symbol with a unique name. The name will be omitted
485   /// in the symbol table if UseNamesOnTempLabels is false (default except
486   /// MCAsmStreamer). The overload without Name uses an unspecified name.
487   MCSymbol *createTempSymbol();
488   MCSymbol *createTempSymbol(const Twine &Name, bool AlwaysAddSuffix = true);
489 
490   /// Create a temporary symbol with a unique name whose name cannot be
491   /// omitted in the symbol table. This is rarely used.
492   MCSymbol *createNamedTempSymbol();
493   MCSymbol *createNamedTempSymbol(const Twine &Name);
494 
495   /// Create the definition of a directional local symbol for numbered label
496   /// (used for "1:" definitions).
497   MCSymbol *createDirectionalLocalSymbol(unsigned LocalLabelVal);
498 
499   /// Create and return a directional local symbol for numbered label (used
500   /// for "1b" or 1f" references).
501   MCSymbol *getDirectionalLocalSymbol(unsigned LocalLabelVal, bool Before);
502 
503   /// Lookup the symbol inside with the specified \p Name.  If it exists,
504   /// return it.  If not, create a forward reference and return it.
505   ///
506   /// \param Name - The symbol name, which must be unique across all symbols.
507   MCSymbol *getOrCreateSymbol(const Twine &Name);
508 
509   /// Gets a symbol that will be defined to the final stack offset of a local
510   /// variable after codegen.
511   ///
512   /// \param Idx - The index of a local variable passed to \@llvm.localescape.
513   MCSymbol *getOrCreateFrameAllocSymbol(const Twine &FuncName, unsigned Idx);
514 
515   MCSymbol *getOrCreateParentFrameOffsetSymbol(const Twine &FuncName);
516 
517   MCSymbol *getOrCreateLSDASymbol(const Twine &FuncName);
518 
519   /// Get the symbol for \p Name, or null.
520   MCSymbol *lookupSymbol(const Twine &Name) const;
521 
522   /// Set value for a symbol.
523   void setSymbolValue(MCStreamer &Streamer, const Twine &Sym, uint64_t Val);
524 
525   /// getSymbols - Get a reference for the symbol table for clients that
526   /// want to, for example, iterate over all symbols. 'const' because we
527   /// still want any modifications to the table itself to use the MCContext
528   /// APIs.
getSymbols()529   const SymbolTable &getSymbols() const { return Symbols; }
530 
531   /// isInlineAsmLabel - Return true if the name is a label referenced in
532   /// inline assembly.
getInlineAsmLabel(StringRef Name)533   MCSymbol *getInlineAsmLabel(StringRef Name) const {
534     return InlineAsmUsedLabelNames.lookup(Name);
535   }
536 
537   /// registerInlineAsmLabel - Records that the name is a label referenced in
538   /// inline assembly.
539   void registerInlineAsmLabel(MCSymbol *Sym);
540 
541   /// @}
542 
543   /// \name Section Management
544   /// @{
545 
546   enum : unsigned {
547     /// Pass this value as the UniqueID during section creation to get the
548     /// generic section with the given name and characteristics. The usual
549     /// sections such as .text use this ID.
550     GenericSectionID = ~0U
551   };
552 
553   /// Return the MCSection for the specified mach-o section.  This requires
554   /// the operands to be valid.
555   MCSectionMachO *getMachOSection(StringRef Segment, StringRef Section,
556                                   unsigned TypeAndAttributes,
557                                   unsigned Reserved2, SectionKind K,
558                                   const char *BeginSymName = nullptr);
559 
560   MCSectionMachO *getMachOSection(StringRef Segment, StringRef Section,
561                                   unsigned TypeAndAttributes, SectionKind K,
562                                   const char *BeginSymName = nullptr) {
563     return getMachOSection(Segment, Section, TypeAndAttributes, 0, K,
564                            BeginSymName);
565   }
566 
getELFSection(const Twine & Section,unsigned Type,unsigned Flags)567   MCSectionELF *getELFSection(const Twine &Section, unsigned Type,
568                               unsigned Flags) {
569     return getELFSection(Section, Type, Flags, 0, "", false);
570   }
571 
getELFSection(const Twine & Section,unsigned Type,unsigned Flags,unsigned EntrySize)572   MCSectionELF *getELFSection(const Twine &Section, unsigned Type,
573                               unsigned Flags, unsigned EntrySize) {
574     return getELFSection(Section, Type, Flags, EntrySize, "", false,
575                          MCSection::NonUniqueID, nullptr);
576   }
577 
getELFSection(const Twine & Section,unsigned Type,unsigned Flags,unsigned EntrySize,const Twine & Group,bool IsComdat)578   MCSectionELF *getELFSection(const Twine &Section, unsigned Type,
579                               unsigned Flags, unsigned EntrySize,
580                               const Twine &Group, bool IsComdat) {
581     return getELFSection(Section, Type, Flags, EntrySize, Group, IsComdat,
582                          MCSection::NonUniqueID, nullptr);
583   }
584 
585   MCSectionELF *getELFSection(const Twine &Section, unsigned Type,
586                               unsigned Flags, unsigned EntrySize,
587                               const Twine &Group, bool IsComdat,
588                               unsigned UniqueID,
589                               const MCSymbolELF *LinkedToSym);
590 
591   MCSectionELF *getELFSection(const Twine &Section, unsigned Type,
592                               unsigned Flags, unsigned EntrySize,
593                               const MCSymbolELF *Group, bool IsComdat,
594                               unsigned UniqueID,
595                               const MCSymbolELF *LinkedToSym);
596 
597   /// Get a section with the provided group identifier. This section is
598   /// named by concatenating \p Prefix with '.' then \p Suffix. The \p Type
599   /// describes the type of the section and \p Flags are used to further
600   /// configure this named section.
601   MCSectionELF *getELFNamedSection(const Twine &Prefix, const Twine &Suffix,
602                                    unsigned Type, unsigned Flags,
603                                    unsigned EntrySize = 0);
604 
605   MCSectionELF *createELFRelSection(const Twine &Name, unsigned Type,
606                                     unsigned Flags, unsigned EntrySize,
607                                     const MCSymbolELF *Group,
608                                     const MCSectionELF *RelInfoSection);
609 
610   MCSectionELF *createELFGroupSection(const MCSymbolELF *Group, bool IsComdat);
611 
612   void recordELFMergeableSectionInfo(StringRef SectionName, unsigned Flags,
613                                      unsigned UniqueID, unsigned EntrySize);
614 
615   bool isELFImplicitMergeableSectionNamePrefix(StringRef Name);
616 
617   bool isELFGenericMergeableSection(StringRef Name);
618 
619   /// Return the unique ID of the section with the given name, flags and entry
620   /// size, if it exists.
621   std::optional<unsigned> getELFUniqueIDForEntsize(StringRef SectionName,
622                                                    unsigned Flags,
623                                                    unsigned EntrySize);
624 
625   MCSectionGOFF *getGOFFSection(StringRef Section, SectionKind Kind,
626                                 MCSection *Parent, const MCExpr *SubsectionId);
627 
628   MCSectionCOFF *getCOFFSection(StringRef Section, unsigned Characteristics,
629                                 SectionKind Kind, StringRef COMDATSymName,
630                                 int Selection,
631                                 unsigned UniqueID = GenericSectionID,
632                                 const char *BeginSymName = nullptr);
633 
634   MCSectionCOFF *getCOFFSection(StringRef Section, unsigned Characteristics,
635                                 SectionKind Kind,
636                                 const char *BeginSymName = nullptr);
637 
638   /// Gets or creates a section equivalent to Sec that is associated with the
639   /// section containing KeySym. For example, to create a debug info section
640   /// associated with an inline function, pass the normal debug info section
641   /// as Sec and the function symbol as KeySym.
642   MCSectionCOFF *
643   getAssociativeCOFFSection(MCSectionCOFF *Sec, const MCSymbol *KeySym,
644                             unsigned UniqueID = GenericSectionID);
645 
646   MCSectionSPIRV *getSPIRVSection();
647 
648   MCSectionWasm *getWasmSection(const Twine &Section, SectionKind K,
649                                 unsigned Flags = 0) {
650     return getWasmSection(Section, K, Flags, nullptr);
651   }
652 
getWasmSection(const Twine & Section,SectionKind K,unsigned Flags,const char * BeginSymName)653   MCSectionWasm *getWasmSection(const Twine &Section, SectionKind K,
654                                 unsigned Flags, const char *BeginSymName) {
655     return getWasmSection(Section, K, Flags, "", ~0, BeginSymName);
656   }
657 
getWasmSection(const Twine & Section,SectionKind K,unsigned Flags,const Twine & Group,unsigned UniqueID)658   MCSectionWasm *getWasmSection(const Twine &Section, SectionKind K,
659                                 unsigned Flags, const Twine &Group,
660                                 unsigned UniqueID) {
661     return getWasmSection(Section, K, Flags, Group, UniqueID, nullptr);
662   }
663 
664   MCSectionWasm *getWasmSection(const Twine &Section, SectionKind K,
665                                 unsigned Flags, const Twine &Group,
666                                 unsigned UniqueID, const char *BeginSymName);
667 
668   MCSectionWasm *getWasmSection(const Twine &Section, SectionKind K,
669                                 unsigned Flags, const MCSymbolWasm *Group,
670                                 unsigned UniqueID, const char *BeginSymName);
671 
672   /// Get the section for the provided Section name
673   MCSectionDXContainer *getDXContainerSection(StringRef Section, SectionKind K);
674 
675   bool hasXCOFFSection(StringRef Section,
676                        XCOFF::CsectProperties CsectProp) const;
677 
678   MCSectionXCOFF *getXCOFFSection(
679       StringRef Section, SectionKind K,
680       std::optional<XCOFF::CsectProperties> CsectProp = std::nullopt,
681       bool MultiSymbolsAllowed = false, const char *BeginSymName = nullptr,
682       std::optional<XCOFF::DwarfSectionSubtypeFlags> DwarfSubtypeFlags =
683           std::nullopt);
684 
685   // Create and save a copy of STI and return a reference to the copy.
686   MCSubtargetInfo &getSubtargetCopy(const MCSubtargetInfo &STI);
687 
getBBAddrMapVersion()688   uint8_t getBBAddrMapVersion() const { return BBAddrMapVersion; }
689 
690   /// @}
691 
692   /// \name Dwarf Management
693   /// @{
694 
695   /// Get the compilation directory for DW_AT_comp_dir
696   /// The compilation directory should be set with \c setCompilationDir before
697   /// calling this function. If it is unset, an empty string will be returned.
getCompilationDir()698   StringRef getCompilationDir() const { return CompilationDir; }
699 
700   /// Set the compilation directory for DW_AT_comp_dir
setCompilationDir(StringRef S)701   void setCompilationDir(StringRef S) { CompilationDir = S.str(); }
702 
703   /// Add an entry to the debug prefix map.
704   void addDebugPrefixMapEntry(const std::string &From, const std::string &To);
705 
706   /// Remap one path in-place as per the debug prefix map.
707   void remapDebugPath(SmallVectorImpl<char> &Path);
708 
709   // Remaps all debug directory paths in-place as per the debug prefix map.
710   void RemapDebugPaths();
711 
712   /// Get the main file name for use in error messages and debug
713   /// info. This can be set to ensure we've got the correct file name
714   /// after preprocessing or for -save-temps.
getMainFileName()715   const std::string &getMainFileName() const { return MainFileName; }
716 
717   /// Set the main file name and override the default.
setMainFileName(StringRef S)718   void setMainFileName(StringRef S) { MainFileName = std::string(S); }
719 
720   /// Creates an entry in the dwarf file and directory tables.
721   Expected<unsigned> getDwarfFile(StringRef Directory, StringRef FileName,
722                                   unsigned FileNumber,
723                                   std::optional<MD5::MD5Result> Checksum,
724                                   std::optional<StringRef> Source,
725                                   unsigned CUID);
726 
727   bool isValidDwarfFileNumber(unsigned FileNumber, unsigned CUID = 0);
728 
getMCDwarfLineTables()729   const std::map<unsigned, MCDwarfLineTable> &getMCDwarfLineTables() const {
730     return MCDwarfLineTablesCUMap;
731   }
732 
getMCDwarfLineTable(unsigned CUID)733   MCDwarfLineTable &getMCDwarfLineTable(unsigned CUID) {
734     return MCDwarfLineTablesCUMap[CUID];
735   }
736 
getMCDwarfLineTable(unsigned CUID)737   const MCDwarfLineTable &getMCDwarfLineTable(unsigned CUID) const {
738     auto I = MCDwarfLineTablesCUMap.find(CUID);
739     assert(I != MCDwarfLineTablesCUMap.end());
740     return I->second;
741   }
742 
743   const SmallVectorImpl<MCDwarfFile> &getMCDwarfFiles(unsigned CUID = 0) {
744     return getMCDwarfLineTable(CUID).getMCDwarfFiles();
745   }
746 
747   const SmallVectorImpl<std::string> &getMCDwarfDirs(unsigned CUID = 0) {
748     return getMCDwarfLineTable(CUID).getMCDwarfDirs();
749   }
750 
getDwarfCompileUnitID()751   unsigned getDwarfCompileUnitID() { return DwarfCompileUnitID; }
752 
setDwarfCompileUnitID(unsigned CUIndex)753   void setDwarfCompileUnitID(unsigned CUIndex) { DwarfCompileUnitID = CUIndex; }
754 
755   /// Specifies the "root" file and directory of the compilation unit.
756   /// These are "file 0" and "directory 0" in DWARF v5.
setMCLineTableRootFile(unsigned CUID,StringRef CompilationDir,StringRef Filename,std::optional<MD5::MD5Result> Checksum,std::optional<StringRef> Source)757   void setMCLineTableRootFile(unsigned CUID, StringRef CompilationDir,
758                               StringRef Filename,
759                               std::optional<MD5::MD5Result> Checksum,
760                               std::optional<StringRef> Source) {
761     getMCDwarfLineTable(CUID).setRootFile(CompilationDir, Filename, Checksum,
762                                           Source);
763   }
764 
765   /// Reports whether MD5 checksum usage is consistent (all-or-none).
isDwarfMD5UsageConsistent(unsigned CUID)766   bool isDwarfMD5UsageConsistent(unsigned CUID) const {
767     return getMCDwarfLineTable(CUID).isMD5UsageConsistent();
768   }
769 
770   /// Saves the information from the currently parsed dwarf .loc directive
771   /// and sets DwarfLocSeen.  When the next instruction is assembled an entry
772   /// in the line number table with this information and the address of the
773   /// instruction will be created.
setCurrentDwarfLoc(unsigned FileNum,unsigned Line,unsigned Column,unsigned Flags,unsigned Isa,unsigned Discriminator)774   void setCurrentDwarfLoc(unsigned FileNum, unsigned Line, unsigned Column,
775                           unsigned Flags, unsigned Isa,
776                           unsigned Discriminator) {
777     CurrentDwarfLoc.setFileNum(FileNum);
778     CurrentDwarfLoc.setLine(Line);
779     CurrentDwarfLoc.setColumn(Column);
780     CurrentDwarfLoc.setFlags(Flags);
781     CurrentDwarfLoc.setIsa(Isa);
782     CurrentDwarfLoc.setDiscriminator(Discriminator);
783     DwarfLocSeen = true;
784   }
785 
clearDwarfLocSeen()786   void clearDwarfLocSeen() { DwarfLocSeen = false; }
787 
getDwarfLocSeen()788   bool getDwarfLocSeen() { return DwarfLocSeen; }
getCurrentDwarfLoc()789   const MCDwarfLoc &getCurrentDwarfLoc() { return CurrentDwarfLoc; }
790 
getGenDwarfForAssembly()791   bool getGenDwarfForAssembly() { return GenDwarfForAssembly; }
setGenDwarfForAssembly(bool Value)792   void setGenDwarfForAssembly(bool Value) { GenDwarfForAssembly = Value; }
getGenDwarfFileNumber()793   unsigned getGenDwarfFileNumber() { return GenDwarfFileNumber; }
794   EmitDwarfUnwindType emitDwarfUnwindInfo() const;
795   bool emitCompactUnwindNonCanonical() const;
796 
setGenDwarfFileNumber(unsigned FileNumber)797   void setGenDwarfFileNumber(unsigned FileNumber) {
798     GenDwarfFileNumber = FileNumber;
799   }
800 
801   /// Specifies information about the "root file" for assembler clients
802   /// (e.g., llvm-mc). Assumes compilation dir etc. have been set up.
803   void setGenDwarfRootFile(StringRef FileName, StringRef Buffer);
804 
getGenDwarfSectionSyms()805   const SetVector<MCSection *> &getGenDwarfSectionSyms() {
806     return SectionsForRanges;
807   }
808 
addGenDwarfSection(MCSection * Sec)809   bool addGenDwarfSection(MCSection *Sec) {
810     return SectionsForRanges.insert(Sec);
811   }
812 
813   void finalizeDwarfSections(MCStreamer &MCOS);
814 
getMCGenDwarfLabelEntries()815   const std::vector<MCGenDwarfLabelEntry> &getMCGenDwarfLabelEntries() const {
816     return MCGenDwarfLabelEntries;
817   }
818 
addMCGenDwarfLabelEntry(const MCGenDwarfLabelEntry & E)819   void addMCGenDwarfLabelEntry(const MCGenDwarfLabelEntry &E) {
820     MCGenDwarfLabelEntries.push_back(E);
821   }
822 
setDwarfDebugFlags(StringRef S)823   void setDwarfDebugFlags(StringRef S) { DwarfDebugFlags = S; }
getDwarfDebugFlags()824   StringRef getDwarfDebugFlags() { return DwarfDebugFlags; }
825 
setDwarfDebugProducer(StringRef S)826   void setDwarfDebugProducer(StringRef S) { DwarfDebugProducer = S; }
getDwarfDebugProducer()827   StringRef getDwarfDebugProducer() { return DwarfDebugProducer; }
828 
setDwarfFormat(dwarf::DwarfFormat f)829   void setDwarfFormat(dwarf::DwarfFormat f) { DwarfFormat = f; }
getDwarfFormat()830   dwarf::DwarfFormat getDwarfFormat() const { return DwarfFormat; }
831 
setDwarfVersion(uint16_t v)832   void setDwarfVersion(uint16_t v) { DwarfVersion = v; }
getDwarfVersion()833   uint16_t getDwarfVersion() const { return DwarfVersion; }
834 
835   /// @}
836 
getSecureLogFile()837   StringRef getSecureLogFile() { return SecureLogFile; }
getSecureLog()838   raw_fd_ostream *getSecureLog() { return SecureLog.get(); }
839 
setSecureLog(std::unique_ptr<raw_fd_ostream> Value)840   void setSecureLog(std::unique_ptr<raw_fd_ostream> Value) {
841     SecureLog = std::move(Value);
842   }
843 
getSecureLogUsed()844   bool getSecureLogUsed() { return SecureLogUsed; }
setSecureLogUsed(bool Value)845   void setSecureLogUsed(bool Value) { SecureLogUsed = Value; }
846 
847   void *allocate(unsigned Size, unsigned Align = 8) {
848     return Allocator.Allocate(Size, Align);
849   }
850 
deallocate(void * Ptr)851   void deallocate(void *Ptr) {}
852 
hadError()853   bool hadError() { return HadError; }
854   void diagnose(const SMDiagnostic &SMD);
855   void reportError(SMLoc L, const Twine &Msg);
856   void reportWarning(SMLoc L, const Twine &Msg);
857 
lookupMacro(StringRef Name)858   const MCAsmMacro *lookupMacro(StringRef Name) {
859     StringMap<MCAsmMacro>::iterator I = MacroMap.find(Name);
860     return (I == MacroMap.end()) ? nullptr : &I->getValue();
861   }
862 
defineMacro(StringRef Name,MCAsmMacro Macro)863   void defineMacro(StringRef Name, MCAsmMacro Macro) {
864     MacroMap.insert(std::make_pair(Name, std::move(Macro)));
865   }
866 
undefineMacro(StringRef Name)867   void undefineMacro(StringRef Name) { MacroMap.erase(Name); }
868 
getMCPseudoProbeTable()869   MCPseudoProbeTable &getMCPseudoProbeTable() { return PseudoProbeTable; }
870 };
871 
872 } // end namespace llvm
873 
874 // operator new and delete aren't allowed inside namespaces.
875 // The throw specifications are mandated by the standard.
876 /// Placement new for using the MCContext's allocator.
877 ///
878 /// This placement form of operator new uses the MCContext's allocator for
879 /// obtaining memory. It is a non-throwing new, which means that it returns
880 /// null on error. (If that is what the allocator does. The current does, so if
881 /// this ever changes, this operator will have to be changed, too.)
882 /// Usage looks like this (assuming there's an MCContext 'Context' in scope):
883 /// \code
884 /// // Default alignment (8)
885 /// IntegerLiteral *Ex = new (Context) IntegerLiteral(arguments);
886 /// // Specific alignment
887 /// IntegerLiteral *Ex2 = new (Context, 4) IntegerLiteral(arguments);
888 /// \endcode
889 /// Please note that you cannot use delete on the pointer; it must be
890 /// deallocated using an explicit destructor call followed by
891 /// \c Context.Deallocate(Ptr).
892 ///
893 /// \param Bytes The number of bytes to allocate. Calculated by the compiler.
894 /// \param C The MCContext that provides the allocator.
895 /// \param Alignment The alignment of the allocated memory (if the underlying
896 ///                  allocator supports it).
897 /// \return The allocated memory. Could be NULL.
898 inline void *operator new(size_t Bytes, llvm::MCContext &C,
899                           size_t Alignment = 8) noexcept {
900   return C.allocate(Bytes, Alignment);
901 }
902 /// Placement delete companion to the new above.
903 ///
904 /// This operator is just a companion to the new above. There is no way of
905 /// invoking it directly; see the new operator for more details. This operator
906 /// is called implicitly by the compiler if a placement new expression using
907 /// the MCContext throws in the object constructor.
delete(void * Ptr,llvm::MCContext & C,size_t)908 inline void operator delete(void *Ptr, llvm::MCContext &C, size_t) noexcept {
909   C.deallocate(Ptr);
910 }
911 
912 /// This placement form of operator new[] uses the MCContext's allocator for
913 /// obtaining memory. It is a non-throwing new[], which means that it returns
914 /// null on error.
915 /// Usage looks like this (assuming there's an MCContext 'Context' in scope):
916 /// \code
917 /// // Default alignment (8)
918 /// char *data = new (Context) char[10];
919 /// // Specific alignment
920 /// char *data = new (Context, 4) char[10];
921 /// \endcode
922 /// Please note that you cannot use delete on the pointer; it must be
923 /// deallocated using an explicit destructor call followed by
924 /// \c Context.Deallocate(Ptr).
925 ///
926 /// \param Bytes The number of bytes to allocate. Calculated by the compiler.
927 /// \param C The MCContext that provides the allocator.
928 /// \param Alignment The alignment of the allocated memory (if the underlying
929 ///                  allocator supports it).
930 /// \return The allocated memory. Could be NULL.
931 inline void *operator new[](size_t Bytes, llvm::MCContext &C,
932                             size_t Alignment = 8) noexcept {
933   return C.allocate(Bytes, Alignment);
934 }
935 
936 /// Placement delete[] companion to the new[] above.
937 ///
938 /// This operator is just a companion to the new[] above. There is no way of
939 /// invoking it directly; see the new[] operator for more details. This operator
940 /// is called implicitly by the compiler if a placement new[] expression using
941 /// the MCContext throws in the object constructor.
942 inline void operator delete[](void *Ptr, llvm::MCContext &C) noexcept {
943   C.deallocate(Ptr);
944 }
945 
946 #endif // LLVM_MC_MCCONTEXT_H
947