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/SetVector.h"
15 #include "llvm/ADT/SmallString.h"
16 #include "llvm/ADT/SmallVector.h"
17 #include "llvm/ADT/StringMap.h"
18 #include "llvm/MC/MCDwarf.h"
19 #include "llvm/MC/MCStreamer.h"
20 #include "llvm/MC/SectionKind.h"
21 #include "llvm/Support/Allocator.h"
22 #include "llvm/Support/Compiler.h"
23 #include "llvm/Support/raw_ostream.h"
26 #include <vector> // FIXME: Shouldn't be needed.
36 class MCObjectFileInfo
;
46 /// MCContext - Context object for machine code objects. This class owns all
47 /// of the sections that it creates.
50 MCContext(const MCContext
&) LLVM_DELETED_FUNCTION
;
51 MCContext
&operator=(const MCContext
&) LLVM_DELETED_FUNCTION
;
53 typedef StringMap
<MCSymbol
*, BumpPtrAllocator
&> SymbolTable
;
55 /// The SourceMgr for this object, if any.
56 const SourceMgr
*SrcMgr
;
58 /// The MCAsmInfo for this target.
61 /// The MCRegisterInfo for this target.
62 const MCRegisterInfo
*MRI
;
64 /// The MCObjectFileInfo for this target.
65 const MCObjectFileInfo
*MOFI
;
67 /// Allocator - Allocator object used for creating machine code objects.
69 /// We use a bump pointer allocator to avoid the need to track all allocated
71 BumpPtrAllocator Allocator
;
73 /// Symbols - Bindings of names to symbols.
76 /// A maping from a local label number and an instance count to a symbol.
77 /// For example, in the assembly
81 /// We have three labels represented by the pairs (1, 0), (2, 0) and (1, 1)
82 DenseMap
<std::pair
<unsigned, unsigned>, MCSymbol
*> LocalSymbols
;
84 /// UsedNames - Keeps tracks of names that were used both for used declared
85 /// and artificial symbols.
86 StringMap
<bool, BumpPtrAllocator
&> UsedNames
;
88 /// NextUniqueID - The next ID to dole out to an unnamed assembler temporary
90 unsigned NextUniqueID
;
92 /// Instances of directional local labels.
93 DenseMap
<unsigned, MCLabel
*> Instances
;
94 /// NextInstance() creates the next instance of the directional local label
95 /// for the LocalLabelVal and adds it to the map if needed.
96 unsigned NextInstance(unsigned LocalLabelVal
);
97 /// GetInstance() gets the current instance of the directional local label
98 /// for the LocalLabelVal and adds it to the map if needed.
99 unsigned GetInstance(unsigned LocalLabelVal
);
101 /// The file name of the log file from the environment variable
102 /// AS_SECURE_LOG_FILE. Which must be set before the .secure_log_unique
103 /// directive is used or it is an error.
105 /// The stream that gets written to for the .secure_log_unique directive.
106 raw_ostream
*SecureLog
;
107 /// Boolean toggled when .secure_log_unique / .secure_log_reset is seen to
108 /// catch errors if .secure_log_unique appears twice without
109 /// .secure_log_reset appearing between them.
112 /// The compilation directory to use for DW_AT_comp_dir.
113 SmallString
<128> CompilationDir
;
115 /// The main file name if passed in explicitly.
116 std::string MainFileName
;
118 /// The dwarf file and directory tables from the dwarf .file directive.
119 /// We now emit a line table for each compile unit. To reduce the prologue
120 /// size of each line table, the files and directories used by each compile
121 /// unit are separated.
122 std::map
<unsigned, MCDwarfLineTable
> MCDwarfLineTablesCUMap
;
124 /// The current dwarf line information from the last dwarf .loc directive.
125 MCDwarfLoc CurrentDwarfLoc
;
128 /// Generate dwarf debugging info for assembly source files.
129 bool GenDwarfForAssembly
;
131 /// The current dwarf file number when generate dwarf debugging info for
132 /// assembly source files.
133 unsigned GenDwarfFileNumber
;
135 /// Symbols created for the start and end of each section, used for
136 /// generating the .debug_ranges and .debug_aranges sections.
137 MapVector
<const MCSection
*, std::pair
<MCSymbol
*, MCSymbol
*> >
140 /// The information gathered from labels that will have dwarf label
141 /// entries when generating dwarf assembly source files.
142 std::vector
<MCGenDwarfLabelEntry
> MCGenDwarfLabelEntries
;
144 /// The string to embed in the debug information for the compile unit, if
146 StringRef DwarfDebugFlags
;
148 /// The string to embed in as the dwarf AT_producer for the compile unit, if
150 StringRef DwarfDebugProducer
;
152 /// The maximum version of dwarf that we should emit.
153 uint16_t DwarfVersion
;
155 /// Honor temporary labels, this is useful for debugging semantic
156 /// differences between temporary and non-temporary labels (primarily on
158 bool AllowTemporaryLabels
;
160 /// The Compile Unit ID that we are currently processing.
161 unsigned DwarfCompileUnitID
;
163 typedef std::pair
<std::string
, std::string
> SectionGroupPair
;
164 typedef std::tuple
<std::string
, std::string
, int> SectionGroupTriple
;
166 StringMap
<const MCSectionMachO
*> MachOUniquingMap
;
167 std::map
<SectionGroupPair
, const MCSectionELF
*> ELFUniquingMap
;
168 std::map
<SectionGroupTriple
, const MCSectionCOFF
*> COFFUniquingMap
;
170 /// Do automatic reset in destructor
173 MCSymbol
*CreateSymbol(StringRef Name
);
175 MCSymbol
*getOrCreateDirectionalLocalSymbol(unsigned LocalLabelVal
,
179 explicit MCContext(const MCAsmInfo
*MAI
, const MCRegisterInfo
*MRI
,
180 const MCObjectFileInfo
*MOFI
,
181 const SourceMgr
*Mgr
= nullptr, bool DoAutoReset
= true);
184 const SourceMgr
*getSourceManager() const { return SrcMgr
; }
186 const MCAsmInfo
*getAsmInfo() const { return MAI
; }
188 const MCRegisterInfo
*getRegisterInfo() const { return MRI
; }
190 const MCObjectFileInfo
*getObjectFileInfo() const { return MOFI
; }
192 void setAllowTemporaryLabels(bool Value
) { AllowTemporaryLabels
= Value
; }
194 /// @name Module Lifetime Management
197 /// reset - return object to right after construction state to prepare
198 /// to process a new module
203 /// @name Symbol Management
206 /// CreateLinkerPrivateTempSymbol - Create and return a new linker temporary
207 /// symbol with a unique but unspecified name.
208 MCSymbol
*CreateLinkerPrivateTempSymbol();
210 /// CreateTempSymbol - Create and return a new assembler temporary symbol
211 /// with a unique but unspecified name.
212 MCSymbol
*CreateTempSymbol();
214 /// getUniqueSymbolID() - Return a unique identifier for use in constructing
216 unsigned getUniqueSymbolID() { return NextUniqueID
++; }
218 /// Create the definition of a directional local symbol for numbered label
219 /// (used for "1:" definitions).
220 MCSymbol
*CreateDirectionalLocalSymbol(unsigned LocalLabelVal
);
222 /// Create and return a directional local symbol for numbered label (used
223 /// for "1b" or 1f" references).
224 MCSymbol
*GetDirectionalLocalSymbol(unsigned LocalLabelVal
, bool Before
);
226 /// GetOrCreateSymbol - Lookup the symbol inside with the specified
227 /// @p Name. If it exists, return it. If not, create a forward
228 /// reference and return it.
230 /// @param Name - The symbol name, which must be unique across all symbols.
231 MCSymbol
*GetOrCreateSymbol(StringRef Name
);
232 MCSymbol
*GetOrCreateSymbol(const Twine
&Name
);
234 /// LookupSymbol - Get the symbol for \p Name, or null.
235 MCSymbol
*LookupSymbol(StringRef Name
) const;
236 MCSymbol
*LookupSymbol(const Twine
&Name
) const;
238 /// getSymbols - Get a reference for the symbol table for clients that
239 /// want to, for example, iterate over all symbols. 'const' because we
240 /// still want any modifications to the table itself to use the MCContext
242 const SymbolTable
&getSymbols() const {
248 /// @name Section Management
251 /// getMachOSection - Return the MCSection for the specified mach-o section.
252 /// This requires the operands to be valid.
253 const MCSectionMachO
*getMachOSection(StringRef Segment
,
255 unsigned TypeAndAttributes
,
258 const MCSectionMachO
*getMachOSection(StringRef Segment
,
260 unsigned TypeAndAttributes
,
262 return getMachOSection(Segment
, Section
, TypeAndAttributes
, 0, K
);
265 const MCSectionELF
*getELFSection(StringRef Section
, unsigned Type
,
266 unsigned Flags
, SectionKind Kind
);
268 const MCSectionELF
*getELFSection(StringRef Section
, unsigned Type
,
269 unsigned Flags
, SectionKind Kind
,
270 unsigned EntrySize
, StringRef Group
);
272 void renameELFSection(const MCSectionELF
*Section
, StringRef Name
);
274 const MCSectionELF
*CreateELFGroupSection();
276 const MCSectionCOFF
*getCOFFSection(StringRef Section
,
277 unsigned Characteristics
,
279 StringRef COMDATSymName
, int Selection
);
281 const MCSectionCOFF
*getCOFFSection(StringRef Section
,
282 unsigned Characteristics
,
285 const MCSectionCOFF
*getCOFFSection(StringRef Section
);
287 /// Gets or creates a section equivalent to Sec that is associated with the
288 /// section containing KeySym. For example, to create a debug info section
289 /// associated with an inline function, pass the normal debug info section
290 /// as Sec and the function symbol as KeySym.
291 const MCSectionCOFF
*getAssociativeCOFFSection(const MCSectionCOFF
*Sec
,
292 const MCSymbol
*KeySym
);
296 /// @name Dwarf Management
299 /// \brief Get the compilation directory for DW_AT_comp_dir
300 /// This can be overridden by clients which want to control the reported
301 /// compilation directory and have it be something other than the current
302 /// working directory.
303 /// Returns an empty string if the current directory cannot be determined.
304 StringRef
getCompilationDir() const { return CompilationDir
; }
306 /// \brief Set the compilation directory for DW_AT_comp_dir
307 /// Override the default (CWD) compilation directory.
308 void setCompilationDir(StringRef S
) { CompilationDir
= S
.str(); }
310 /// \brief Get the main file name for use in error messages and debug
311 /// info. This can be set to ensure we've got the correct file name
312 /// after preprocessing or for -save-temps.
313 const std::string
&getMainFileName() const { return MainFileName
; }
315 /// \brief Set the main file name and override the default.
316 void setMainFileName(StringRef S
) { MainFileName
= S
; }
318 /// GetDwarfFile - creates an entry in the dwarf file and directory tables.
319 unsigned GetDwarfFile(StringRef Directory
, StringRef FileName
,
320 unsigned FileNumber
, unsigned CUID
);
322 bool isValidDwarfFileNumber(unsigned FileNumber
, unsigned CUID
= 0);
324 const std::map
<unsigned, MCDwarfLineTable
> &getMCDwarfLineTables() const {
325 return MCDwarfLineTablesCUMap
;
328 MCDwarfLineTable
&getMCDwarfLineTable(unsigned CUID
) {
329 return MCDwarfLineTablesCUMap
[CUID
];
332 const MCDwarfLineTable
&getMCDwarfLineTable(unsigned CUID
) const {
333 auto I
= MCDwarfLineTablesCUMap
.find(CUID
);
334 assert(I
!= MCDwarfLineTablesCUMap
.end());
338 const SmallVectorImpl
<MCDwarfFile
> &getMCDwarfFiles(unsigned CUID
= 0) {
339 return getMCDwarfLineTable(CUID
).getMCDwarfFiles();
341 const SmallVectorImpl
<std::string
> &getMCDwarfDirs(unsigned CUID
= 0) {
342 return getMCDwarfLineTable(CUID
).getMCDwarfDirs();
345 bool hasMCLineSections() const {
346 for (const auto &Table
: MCDwarfLineTablesCUMap
)
347 if (!Table
.second
.getMCDwarfFiles().empty() || Table
.second
.getLabel())
351 unsigned getDwarfCompileUnitID() {
352 return DwarfCompileUnitID
;
354 void setDwarfCompileUnitID(unsigned CUIndex
) {
355 DwarfCompileUnitID
= CUIndex
;
357 void setMCLineTableCompilationDir(unsigned CUID
, StringRef CompilationDir
) {
358 getMCDwarfLineTable(CUID
).setCompilationDir(CompilationDir
);
361 /// setCurrentDwarfLoc - saves the information from the currently parsed
362 /// dwarf .loc directive and sets DwarfLocSeen. When the next instruction
363 /// is assembled an entry in the line number table with this information and
364 /// the address of the instruction will be created.
365 void setCurrentDwarfLoc(unsigned FileNum
, unsigned Line
, unsigned Column
,
366 unsigned Flags
, unsigned Isa
,
367 unsigned Discriminator
) {
368 CurrentDwarfLoc
.setFileNum(FileNum
);
369 CurrentDwarfLoc
.setLine(Line
);
370 CurrentDwarfLoc
.setColumn(Column
);
371 CurrentDwarfLoc
.setFlags(Flags
);
372 CurrentDwarfLoc
.setIsa(Isa
);
373 CurrentDwarfLoc
.setDiscriminator(Discriminator
);
376 void ClearDwarfLocSeen() { DwarfLocSeen
= false; }
378 bool getDwarfLocSeen() { return DwarfLocSeen
; }
379 const MCDwarfLoc
&getCurrentDwarfLoc() { return CurrentDwarfLoc
; }
381 bool getGenDwarfForAssembly() { return GenDwarfForAssembly
; }
382 void setGenDwarfForAssembly(bool Value
) { GenDwarfForAssembly
= Value
; }
383 unsigned getGenDwarfFileNumber() { return GenDwarfFileNumber
; }
384 void setGenDwarfFileNumber(unsigned FileNumber
) {
385 GenDwarfFileNumber
= FileNumber
;
387 MapVector
<const MCSection
*, std::pair
<MCSymbol
*, MCSymbol
*> > &
388 getGenDwarfSectionSyms() {
389 return SectionStartEndSyms
;
391 std::pair
<MapVector
<const MCSection
*,
392 std::pair
<MCSymbol
*, MCSymbol
*> >::iterator
,
394 addGenDwarfSection(const MCSection
*Sec
) {
395 return SectionStartEndSyms
.insert(
396 std::make_pair(Sec
, std::make_pair(nullptr, nullptr)));
398 void finalizeDwarfSections(MCStreamer
&MCOS
);
399 const std::vector
<MCGenDwarfLabelEntry
> &getMCGenDwarfLabelEntries() const {
400 return MCGenDwarfLabelEntries
;
402 void addMCGenDwarfLabelEntry(const MCGenDwarfLabelEntry
&E
) {
403 MCGenDwarfLabelEntries
.push_back(E
);
406 void setDwarfDebugFlags(StringRef S
) { DwarfDebugFlags
= S
; }
407 StringRef
getDwarfDebugFlags() { return DwarfDebugFlags
; }
409 void setDwarfDebugProducer(StringRef S
) { DwarfDebugProducer
= S
; }
410 StringRef
getDwarfDebugProducer() { return DwarfDebugProducer
; }
412 void setDwarfVersion(uint16_t v
) { DwarfVersion
= v
; }
413 uint16_t getDwarfVersion() const { return DwarfVersion
; }
417 char *getSecureLogFile() { return SecureLogFile
; }
418 raw_ostream
*getSecureLog() { return SecureLog
; }
419 bool getSecureLogUsed() { return SecureLogUsed
; }
420 void setSecureLog(raw_ostream
*Value
) {
423 void setSecureLogUsed(bool Value
) {
424 SecureLogUsed
= Value
;
427 void *Allocate(unsigned Size
, unsigned Align
= 8) {
428 return Allocator
.Allocate(Size
, Align
);
430 void Deallocate(void *Ptr
) {
433 // Unrecoverable error has occurred. Display the best diagnostic we can
434 // and bail via exit(1). For now, most MC backend errors are unrecoverable.
435 // FIXME: We should really do something about that.
436 LLVM_ATTRIBUTE_NORETURN
void FatalError(SMLoc L
, const Twine
&Msg
) const;
439 } // end namespace llvm
441 // operator new and delete aren't allowed inside namespaces.
442 // The throw specifications are mandated by the standard.
443 /// @brief Placement new for using the MCContext's allocator.
445 /// This placement form of operator new uses the MCContext's allocator for
446 /// obtaining memory. It is a non-throwing new, which means that it returns
447 /// null on error. (If that is what the allocator does. The current does, so if
448 /// this ever changes, this operator will have to be changed, too.)
449 /// Usage looks like this (assuming there's an MCContext 'Context' in scope):
451 /// // Default alignment (16)
452 /// IntegerLiteral *Ex = new (Context) IntegerLiteral(arguments);
453 /// // Specific alignment
454 /// IntegerLiteral *Ex2 = new (Context, 8) IntegerLiteral(arguments);
456 /// Please note that you cannot use delete on the pointer; it must be
457 /// deallocated using an explicit destructor call followed by
458 /// @c Context.Deallocate(Ptr).
460 /// @param Bytes The number of bytes to allocate. Calculated by the compiler.
461 /// @param C The MCContext that provides the allocator.
462 /// @param Alignment The alignment of the allocated memory (if the underlying
463 /// allocator supports it).
464 /// @return The allocated memory. Could be NULL.
465 inline void *operator new(size_t Bytes
, llvm::MCContext
&C
,
466 size_t Alignment
= 16) throw () {
467 return C
.Allocate(Bytes
, Alignment
);
469 /// @brief Placement delete companion to the new above.
471 /// This operator is just a companion to the new above. There is no way of
472 /// invoking it directly; see the new operator for more details. This operator
473 /// is called implicitly by the compiler if a placement new expression using
474 /// the MCContext throws in the object constructor.
475 inline void operator delete(void *Ptr
, llvm::MCContext
&C
, size_t)
480 /// This placement form of operator new[] uses the MCContext's allocator for
481 /// obtaining memory. It is a non-throwing new[], which means that it returns
483 /// Usage looks like this (assuming there's an MCContext 'Context' in scope):
485 /// // Default alignment (16)
486 /// char *data = new (Context) char[10];
487 /// // Specific alignment
488 /// char *data = new (Context, 8) char[10];
490 /// Please note that you cannot use delete on the pointer; it must be
491 /// deallocated using an explicit destructor call followed by
492 /// @c Context.Deallocate(Ptr).
494 /// @param Bytes The number of bytes to allocate. Calculated by the compiler.
495 /// @param C The MCContext that provides the allocator.
496 /// @param Alignment The alignment of the allocated memory (if the underlying
497 /// allocator supports it).
498 /// @return The allocated memory. Could be NULL.
499 inline void *operator new[](size_t Bytes
, llvm::MCContext
& C
,
500 size_t Alignment
= 16) throw () {
501 return C
.Allocate(Bytes
, Alignment
);
504 /// @brief Placement delete[] companion to the new[] above.
506 /// This operator is just a companion to the new[] above. There is no way of
507 /// invoking it directly; see the new[] operator for more details. This operator
508 /// is called implicitly by the compiler if a placement new[] expression using
509 /// the MCContext throws in the object constructor.
510 inline void operator delete[](void *Ptr
, llvm::MCContext
&C
) throw () {