1 //===- MCContext.h - Machine Code Context -----------------------*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 #ifndef LLVM_MC_MCCONTEXT_H
11 #define LLVM_MC_MCCONTEXT_H
13 #include "llvm/ADT/DenseMap.h"
14 #include "llvm/ADT/SmallVector.h"
15 #include "llvm/ADT/StringMap.h"
16 #include "llvm/MC/MCDwarf.h"
17 #include "llvm/MC/SectionKind.h"
18 #include "llvm/Support/Allocator.h"
19 #include "llvm/Support/Compiler.h"
20 #include "llvm/Support/raw_ostream.h"
22 #include <vector> // FIXME: Shouldn't be needed.
32 class MCObjectFileInfo;
41 /// MCContext - Context object for machine code objects. This class owns all
42 /// of the sections that it creates.
45 MCContext(const MCContext&) LLVM_DELETED_FUNCTION;
46 MCContext &operator=(const MCContext&) LLVM_DELETED_FUNCTION;
48 typedef StringMap<MCSymbol*, BumpPtrAllocator&> SymbolTable;
50 /// The SourceMgr for this object, if any.
51 const SourceMgr *SrcMgr;
53 /// The MCAsmInfo for this target.
56 /// The MCRegisterInfo for this target.
57 const MCRegisterInfo &MRI;
59 /// The MCObjectFileInfo for this target.
60 const MCObjectFileInfo *MOFI;
62 /// Allocator - Allocator object used for creating machine code objects.
64 /// We use a bump pointer allocator to avoid the need to track all allocated
66 BumpPtrAllocator Allocator;
68 /// Symbols - Bindings of names to symbols.
71 /// UsedNames - Keeps tracks of names that were used both for used declared
72 /// and artificial symbols.
73 StringMap<bool, BumpPtrAllocator&> UsedNames;
75 /// NextUniqueID - The next ID to dole out to an unnamed assembler temporary
77 unsigned NextUniqueID;
79 /// Instances of directional local labels.
80 DenseMap<unsigned, MCLabel *> Instances;
81 /// NextInstance() creates the next instance of the directional local label
82 /// for the LocalLabelVal and adds it to the map if needed.
83 unsigned NextInstance(int64_t LocalLabelVal);
84 /// GetInstance() gets the current instance of the directional local label
85 /// for the LocalLabelVal and adds it to the map if needed.
86 unsigned GetInstance(int64_t LocalLabelVal);
88 /// The file name of the log file from the environment variable
89 /// AS_SECURE_LOG_FILE. Which must be set before the .secure_log_unique
90 /// directive is used or it is an error.
92 /// The stream that gets written to for the .secure_log_unique directive.
93 raw_ostream *SecureLog;
94 /// Boolean toggled when .secure_log_unique / .secure_log_reset is seen to
95 /// catch errors if .secure_log_unique appears twice without
96 /// .secure_log_reset appearing between them.
99 /// The compilation directory to use for DW_AT_comp_dir.
100 std::string CompilationDir;
102 /// The main file name if passed in explicitly.
103 std::string MainFileName;
105 /// The dwarf file and directory tables from the dwarf .file directive.
106 /// We now emit a line table for each compile unit. To reduce the prologue
107 /// size of each line table, the files and directories used by each compile
108 /// unit are separated.
109 typedef std::map<unsigned, SmallVector<MCDwarfFile *, 4> > MCDwarfFilesMap;
110 MCDwarfFilesMap MCDwarfFilesCUMap;
111 std::map<unsigned, SmallVector<StringRef, 4> > MCDwarfDirsCUMap;
113 /// The current dwarf line information from the last dwarf .loc directive.
114 MCDwarfLoc CurrentDwarfLoc;
117 /// Generate dwarf debugging info for assembly source files.
118 bool GenDwarfForAssembly;
120 /// The current dwarf file number when generate dwarf debugging info for
121 /// assembly source files.
122 unsigned GenDwarfFileNumber;
124 /// The default initial text section that we generate dwarf debugging line
125 /// info for when generating dwarf assembly source files.
126 const MCSection *GenDwarfSection;
127 /// Symbols created for the start and end of this section.
128 MCSymbol *GenDwarfSectionStartSym, *GenDwarfSectionEndSym;
130 /// The information gathered from labels that will have dwarf label
131 /// entries when generating dwarf assembly source files.
132 std::vector<const MCGenDwarfLabelEntry *> MCGenDwarfLabelEntries;
134 /// The string to embed in the debug information for the compile unit, if
136 StringRef DwarfDebugFlags;
138 /// The string to embed in as the dwarf AT_producer for the compile unit, if
140 StringRef DwarfDebugProducer;
142 /// Honor temporary labels, this is useful for debugging semantic
143 /// differences between temporary and non-temporary labels (primarily on
145 bool AllowTemporaryLabels;
147 /// The dwarf line information from the .loc directives for the sections
148 /// with assembled machine instructions have after seeing .loc directives.
149 DenseMap<const MCSection *, MCLineSection *> MCLineSections;
150 /// We need a deterministic iteration order, so we remember the order
151 /// the elements were added.
152 std::vector<const MCSection *> MCLineSectionOrder;
153 /// The Compile Unit ID that we are currently processing.
154 unsigned DwarfCompileUnitID;
155 /// The line table start symbol for each Compile Unit.
156 DenseMap<unsigned, MCSymbol *> MCLineTableSymbols;
158 void *MachOUniquingMap, *ELFUniquingMap, *COFFUniquingMap;
160 /// Do automatic reset in destructor
163 MCSymbol *CreateSymbol(StringRef Name);
166 explicit MCContext(const MCAsmInfo &MAI, const MCRegisterInfo &MRI,
167 const MCObjectFileInfo *MOFI, const SourceMgr *Mgr = 0,
168 bool DoAutoReset = true);
171 const SourceMgr *getSourceManager() const { return SrcMgr; }
173 const MCAsmInfo &getAsmInfo() const { return MAI; }
175 const MCRegisterInfo &getRegisterInfo() const { return MRI; }
177 const MCObjectFileInfo *getObjectFileInfo() const { return MOFI; }
179 void setAllowTemporaryLabels(bool Value) { AllowTemporaryLabels = Value; }
181 /// @name Module Lifetime Management
184 /// reset - return object to right after construction state to prepare
185 /// to process a new module
190 /// @name Symbol Management
193 /// CreateTempSymbol - Create and return a new assembler temporary symbol
194 /// with a unique but unspecified name.
195 MCSymbol *CreateTempSymbol();
197 /// getUniqueSymbolID() - Return a unique identifier for use in constructing
199 unsigned getUniqueSymbolID() { return NextUniqueID++; }
201 /// CreateDirectionalLocalSymbol - Create the definition of a directional
202 /// local symbol for numbered label (used for "1:" definitions).
203 MCSymbol *CreateDirectionalLocalSymbol(int64_t LocalLabelVal);
205 /// GetDirectionalLocalSymbol - Create and return a directional local
206 /// symbol for numbered label (used for "1b" or 1f" references).
207 MCSymbol *GetDirectionalLocalSymbol(int64_t LocalLabelVal, int bORf);
209 /// GetOrCreateSymbol - Lookup the symbol inside with the specified
210 /// @p Name. If it exists, return it. If not, create a forward
211 /// reference and return it.
213 /// @param Name - The symbol name, which must be unique across all symbols.
214 MCSymbol *GetOrCreateSymbol(StringRef Name);
215 MCSymbol *GetOrCreateSymbol(const Twine &Name);
217 /// LookupSymbol - Get the symbol for \p Name, or null.
218 MCSymbol *LookupSymbol(StringRef Name) const;
219 MCSymbol *LookupSymbol(const Twine &Name) const;
221 /// getSymbols - Get a reference for the symbol table for clients that
222 /// want to, for example, iterate over all symbols. 'const' because we
223 /// still want any modifications to the table itself to use the MCContext
225 const SymbolTable &getSymbols() const {
231 /// @name Section Management
234 /// getMachOSection - Return the MCSection for the specified mach-o section.
235 /// This requires the operands to be valid.
236 const MCSectionMachO *getMachOSection(StringRef Segment,
238 unsigned TypeAndAttributes,
241 const MCSectionMachO *getMachOSection(StringRef Segment,
243 unsigned TypeAndAttributes,
245 return getMachOSection(Segment, Section, TypeAndAttributes, 0, K);
248 const MCSectionELF *getELFSection(StringRef Section, unsigned Type,
249 unsigned Flags, SectionKind Kind);
251 const MCSectionELF *getELFSection(StringRef Section, unsigned Type,
252 unsigned Flags, SectionKind Kind,
253 unsigned EntrySize, StringRef Group);
255 const MCSectionELF *CreateELFGroupSection();
257 const MCSection *getCOFFSection(StringRef Section, unsigned Characteristics,
258 int Selection, SectionKind Kind);
260 const MCSection *getCOFFSection(StringRef Section, unsigned Characteristics,
262 return getCOFFSection (Section, Characteristics, 0, Kind);
268 /// @name Dwarf Management
271 /// \brief Get the compilation directory for DW_AT_comp_dir
272 /// This can be overridden by clients which want to control the reported
273 /// compilation directory and have it be something other than the current
274 /// working directory.
275 const std::string &getCompilationDir() const { return CompilationDir; }
277 /// \brief Set the compilation directory for DW_AT_comp_dir
278 /// Override the default (CWD) compilation directory.
279 void setCompilationDir(StringRef S) { CompilationDir = S.str(); }
281 /// \brief Get the main file name for use in error messages and debug
282 /// info. This can be set to ensure we've got the correct file name
283 /// after preprocessing or for -save-temps.
284 const std::string &getMainFileName() const { return MainFileName; }
286 /// \brief Set the main file name and override the default.
287 void setMainFileName(StringRef S) { MainFileName = S.str(); }
289 /// GetDwarfFile - creates an entry in the dwarf file and directory tables.
290 unsigned GetDwarfFile(StringRef Directory, StringRef FileName,
291 unsigned FileNumber, unsigned CUID);
293 bool isValidDwarfFileNumber(unsigned FileNumber, unsigned CUID = 0);
295 bool hasDwarfFiles() const {
296 // Traverse MCDwarfFilesCUMap and check whether each entry is empty.
297 MCDwarfFilesMap::const_iterator MapB, MapE;
298 for (MapB = MCDwarfFilesCUMap.begin(), MapE = MCDwarfFilesCUMap.end();
299 MapB != MapE; MapB++)
300 if (!MapB->second.empty())
305 const SmallVectorImpl<MCDwarfFile *> &getMCDwarfFiles(unsigned CUID = 0) {
306 return MCDwarfFilesCUMap[CUID];
308 const SmallVectorImpl<StringRef> &getMCDwarfDirs(unsigned CUID = 0) {
309 return MCDwarfDirsCUMap[CUID];
312 const DenseMap<const MCSection *, MCLineSection *>
313 &getMCLineSections() const {
314 return MCLineSections;
316 const std::vector<const MCSection *> &getMCLineSectionOrder() const {
317 return MCLineSectionOrder;
319 void addMCLineSection(const MCSection *Sec, MCLineSection *Line) {
320 MCLineSections[Sec] = Line;
321 MCLineSectionOrder.push_back(Sec);
323 unsigned getDwarfCompileUnitID() {
324 return DwarfCompileUnitID;
326 void setDwarfCompileUnitID(unsigned CUIndex) {
327 DwarfCompileUnitID = CUIndex;
329 const DenseMap<unsigned, MCSymbol *> &getMCLineTableSymbols() const {
330 return MCLineTableSymbols;
332 MCSymbol *getMCLineTableSymbol(unsigned ID) const {
333 DenseMap<unsigned, MCSymbol *>::const_iterator CIter =
334 MCLineTableSymbols.find(ID);
335 if (CIter == MCLineTableSymbols.end())
337 return CIter->second;
339 void setMCLineTableSymbol(MCSymbol *Sym, unsigned ID) {
340 MCLineTableSymbols[ID] = Sym;
343 /// setCurrentDwarfLoc - saves the information from the currently parsed
344 /// dwarf .loc directive and sets DwarfLocSeen. When the next instruction
345 /// is assembled an entry in the line number table with this information and
346 /// the address of the instruction will be created.
347 void setCurrentDwarfLoc(unsigned FileNum, unsigned Line, unsigned Column,
348 unsigned Flags, unsigned Isa,
349 unsigned Discriminator) {
350 CurrentDwarfLoc.setFileNum(FileNum);
351 CurrentDwarfLoc.setLine(Line);
352 CurrentDwarfLoc.setColumn(Column);
353 CurrentDwarfLoc.setFlags(Flags);
354 CurrentDwarfLoc.setIsa(Isa);
355 CurrentDwarfLoc.setDiscriminator(Discriminator);
358 void ClearDwarfLocSeen() { DwarfLocSeen = false; }
360 bool getDwarfLocSeen() { return DwarfLocSeen; }
361 const MCDwarfLoc &getCurrentDwarfLoc() { return CurrentDwarfLoc; }
363 bool getGenDwarfForAssembly() { return GenDwarfForAssembly; }
364 void setGenDwarfForAssembly(bool Value) { GenDwarfForAssembly = Value; }
365 unsigned getGenDwarfFileNumber() { return GenDwarfFileNumber; }
366 unsigned nextGenDwarfFileNumber() { return ++GenDwarfFileNumber; }
367 const MCSection *getGenDwarfSection() { return GenDwarfSection; }
368 void setGenDwarfSection(const MCSection *Sec) { GenDwarfSection = Sec; }
369 MCSymbol *getGenDwarfSectionStartSym() { return GenDwarfSectionStartSym; }
370 void setGenDwarfSectionStartSym(MCSymbol *Sym) {
371 GenDwarfSectionStartSym = Sym;
373 MCSymbol *getGenDwarfSectionEndSym() { return GenDwarfSectionEndSym; }
374 void setGenDwarfSectionEndSym(MCSymbol *Sym) {
375 GenDwarfSectionEndSym = Sym;
377 const std::vector<const MCGenDwarfLabelEntry *>
378 &getMCGenDwarfLabelEntries() const {
379 return MCGenDwarfLabelEntries;
381 void addMCGenDwarfLabelEntry(const MCGenDwarfLabelEntry *E) {
382 MCGenDwarfLabelEntries.push_back(E);
385 void setDwarfDebugFlags(StringRef S) { DwarfDebugFlags = S; }
386 StringRef getDwarfDebugFlags() { return DwarfDebugFlags; }
388 void setDwarfDebugProducer(StringRef S) { DwarfDebugProducer = S; }
389 StringRef getDwarfDebugProducer() { return DwarfDebugProducer; }
393 char *getSecureLogFile() { return SecureLogFile; }
394 raw_ostream *getSecureLog() { return SecureLog; }
395 bool getSecureLogUsed() { return SecureLogUsed; }
396 void setSecureLog(raw_ostream *Value) {
399 void setSecureLogUsed(bool Value) {
400 SecureLogUsed = Value;
403 void *Allocate(unsigned Size, unsigned Align = 8) {
404 return Allocator.Allocate(Size, Align);
406 void Deallocate(void *Ptr) {
409 // Unrecoverable error has occured. Display the best diagnostic we can
410 // and bail via exit(1). For now, most MC backend errors are unrecoverable.
411 // FIXME: We should really do something about that.
412 LLVM_ATTRIBUTE_NORETURN void FatalError(SMLoc L, const Twine &Msg);
415 } // end namespace llvm
417 // operator new and delete aren't allowed inside namespaces.
418 // The throw specifications are mandated by the standard.
419 /// @brief Placement new for using the MCContext's allocator.
421 /// This placement form of operator new uses the MCContext's allocator for
422 /// obtaining memory. It is a non-throwing new, which means that it returns
423 /// null on error. (If that is what the allocator does. The current does, so if
424 /// this ever changes, this operator will have to be changed, too.)
425 /// Usage looks like this (assuming there's an MCContext 'Context' in scope):
427 /// // Default alignment (16)
428 /// IntegerLiteral *Ex = new (Context) IntegerLiteral(arguments);
429 /// // Specific alignment
430 /// IntegerLiteral *Ex2 = new (Context, 8) IntegerLiteral(arguments);
432 /// Please note that you cannot use delete on the pointer; it must be
433 /// deallocated using an explicit destructor call followed by
434 /// @c Context.Deallocate(Ptr).
436 /// @param Bytes The number of bytes to allocate. Calculated by the compiler.
437 /// @param C The MCContext that provides the allocator.
438 /// @param Alignment The alignment of the allocated memory (if the underlying
439 /// allocator supports it).
440 /// @return The allocated memory. Could be NULL.
441 inline void *operator new(size_t Bytes, llvm::MCContext &C,
442 size_t Alignment = 16) throw () {
443 return C.Allocate(Bytes, Alignment);
445 /// @brief Placement delete companion to the new above.
447 /// This operator is just a companion to the new above. There is no way of
448 /// invoking it directly; see the new operator for more details. This operator
449 /// is called implicitly by the compiler if a placement new expression using
450 /// the MCContext throws in the object constructor.
451 inline void operator delete(void *Ptr, llvm::MCContext &C, size_t)
456 /// This placement form of operator new[] uses the MCContext's allocator for
457 /// obtaining memory. It is a non-throwing new[], which means that it returns
459 /// Usage looks like this (assuming there's an MCContext 'Context' in scope):
461 /// // Default alignment (16)
462 /// char *data = new (Context) char[10];
463 /// // Specific alignment
464 /// char *data = new (Context, 8) char[10];
466 /// Please note that you cannot use delete on the pointer; it must be
467 /// deallocated using an explicit destructor call followed by
468 /// @c Context.Deallocate(Ptr).
470 /// @param Bytes The number of bytes to allocate. Calculated by the compiler.
471 /// @param C The MCContext that provides the allocator.
472 /// @param Alignment The alignment of the allocated memory (if the underlying
473 /// allocator supports it).
474 /// @return The allocated memory. Could be NULL.
475 inline void *operator new[](size_t Bytes, llvm::MCContext& C,
476 size_t Alignment = 16) throw () {
477 return C.Allocate(Bytes, Alignment);
480 /// @brief Placement delete[] companion to the new[] above.
482 /// This operator is just a companion to the new[] above. There is no way of
483 /// invoking it directly; see the new[] operator for more details. This operator
484 /// is called implicitly by the compiler if a placement new[] expression using
485 /// the MCContext throws in the object constructor.
486 inline void operator delete[](void *Ptr, llvm::MCContext &C) throw () {