1//===- ObjectFile.h - File format independent object file -------*- C++ -*-===//
2//
3// The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10// This file declares a file format independent ObjectFile class.
11//
12//===----------------------------------------------------------------------===//
13
14#ifndef LLVM_OBJECT_OBJECTFILE_H
15#define LLVM_OBJECT_OBJECTFILE_H
16
17#include "llvm/ADT/StringRef.h"
18#include "llvm/ADT/Triple.h"
19#include "llvm/ADT/iterator_range.h"
20#include "llvm/BinaryFormat/Magic.h"
21#include "llvm/MC/SubtargetFeature.h"
22#include "llvm/Object/Binary.h"
23#include "llvm/Object/Error.h"
24#include "llvm/Object/SymbolicFile.h"
25#include "llvm/Support/Casting.h"
26#include "llvm/Support/Error.h"
27#include "llvm/Support/FileSystem.h"
28#include "llvm/Support/MemoryBuffer.h"
29#include <cassert>
30#include <cstdint>
31#include <memory>
32#include <system_error>
33
34namespace llvm {
35
36class ARMAttributeParser;
37
38namespace object {
39
40class COFFObjectFile;
41class MachOObjectFile;
42class ObjectFile;
43class SectionRef;
44class SymbolRef;
45class symbol_iterator;
46class WasmObjectFile;
47
48using section_iterator = content_iterator<SectionRef>;
49
50/// This is a value type class that represents a single relocation in the list
51/// of relocations in the object file.
52class RelocationRef {
53 DataRefImpl RelocationPimpl;
54 const ObjectFile *OwningObject = nullptr;
55
56public:
57 RelocationRef() = default;
58 RelocationRef(DataRefImpl RelocationP, const ObjectFile *Owner);
59
60 bool operator==(const RelocationRef &Other) const;
61
62 void moveNext();
63
64 uint64_t getOffset() const;
65 symbol_iterator getSymbol() const;
66 uint64_t getType() const;
67
68 /// Get a string that represents the type of this relocation.
69 ///
70 /// This is for display purposes only.
71 void getTypeName(SmallVectorImpl<char> &Result) const;
72
73 DataRefImpl getRawDataRefImpl() const;
74 const ObjectFile *getObject() const;
75};
76
77using relocation_iterator = content_iterator<RelocationRef>;
78
79/// This is a value type class that represents a single section in the list of
80/// sections in the object file.
81class SectionRef {
82 friend class SymbolRef;
83
84 DataRefImpl SectionPimpl;
85 const ObjectFile *OwningObject = nullptr;
86
87public:
88 SectionRef() = default;
89 SectionRef(DataRefImpl SectionP, const ObjectFile *Owner);
90
91 bool operator==(const SectionRef &Other) const;
92 bool operator!=(const SectionRef &Other) const;
93 bool operator<(const SectionRef &Other) const;
94
95 void moveNext();
96
97 std::error_code getName(StringRef &Result) const;
98 uint64_t getAddress() const;
99 uint64_t getIndex() const;
100 uint64_t getSize() const;
101 std::error_code getContents(StringRef &Result) const;
102
103 /// Get the alignment of this section as the actual value (not log 2).
104 uint64_t getAlignment() const;
105
106 bool isCompressed() const;
107 /// Whether this section contains instructions.
108 bool isText() const;
109 /// Whether this section contains data, not instructions.
110 bool isData() const;
111 /// Whether this section contains BSS uninitialized data.
112 bool isBSS() const;
113 bool isVirtual() const;
114 bool isBitcode() const;
115 bool isStripped() const;
116
117 /// Whether this section will be placed in the text segment, according to the
118 /// Berkeley size format. This is true if the section is allocatable, and
119 /// contains either code or readonly data.
120 bool isBerkeleyText() const;
121 /// Whether this section will be placed in the data segment, according to the
122 /// Berkeley size format. This is true if the section is allocatable and
123 /// contains data (e.g. PROGBITS), but is not text.
124 bool isBerkeleyData() const;
125
126 bool containsSymbol(SymbolRef S) const;
127
128 relocation_iterator relocation_begin() const;
129 relocation_iterator relocation_end() const;
130 iterator_range<relocation_iterator> relocations() const {
131 return make_range(relocation_begin(), relocation_end());
132 }
133 section_iterator getRelocatedSection() const;
134
135 DataRefImpl getRawDataRefImpl() const;
136 const ObjectFile *getObject() const;
137};
138
139/// This is a value type class that represents a single symbol in the list of
140/// symbols in the object file.
141class SymbolRef : public BasicSymbolRef {
142 friend class SectionRef;
143
144public:
145 enum Type {
146 ST_Unknown, // Type not specified
147 ST_Data,
148 ST_Debug,
149 ST_File,
150 ST_Function,
151 ST_Other
152 };
153
154 SymbolRef() = default;
155 SymbolRef(DataRefImpl SymbolP, const ObjectFile *Owner);
156 SymbolRef(const BasicSymbolRef &B) : BasicSymbolRef(B) {
157 assert(isa<ObjectFile>(BasicSymbolRef::getObject()));
158 }
159
160 Expected<StringRef> getName() const;
161 /// Returns the symbol virtual address (i.e. address at which it will be
162 /// mapped).
163 Expected<uint64_t> getAddress() const;
164
165 /// Return the value of the symbol depending on the object this can be an
166 /// offset or a virtual address.
167 uint64_t getValue() const;
168
169 /// Get the alignment of this symbol as the actual value (not log 2).
170 uint32_t getAlignment() const;
171 uint64_t getCommonSize() const;
172 Expected<SymbolRef::Type> getType() const;
173
174 /// Get section this symbol is defined in reference to. Result is
175 /// end_sections() if it is undefined or is an absolute symbol.
176 Expected<section_iterator> getSection() const;
177
178 const ObjectFile *getObject() const;
179};
180
181class symbol_iterator : public basic_symbol_iterator {
182public:
183 symbol_iterator(SymbolRef Sym) : basic_symbol_iterator(Sym) {}
184 symbol_iterator(const basic_symbol_iterator &B)
185 : basic_symbol_iterator(SymbolRef(B->getRawDataRefImpl(),
186 cast<ObjectFile>(B->getObject()))) {}
187
188 const SymbolRef *operator->() const {
189 const BasicSymbolRef &P = basic_symbol_iterator::operator *();
190 return static_cast<const SymbolRef*>(&P);
191 }
192
193 const SymbolRef &operator*() const {
194 const BasicSymbolRef &P = basic_symbol_iterator::operator *();
195 return static_cast<const SymbolRef&>(P);
196 }
197};
198
199/// This class is the base class for all object file types. Concrete instances
200/// of this object are created by createObjectFile, which figures out which type
201/// to create.
202class ObjectFile : public SymbolicFile {
203 virtual void anchor();
204
205protected:
206 ObjectFile(unsigned int Type, MemoryBufferRef Source);
207
208 const uint8_t *base() const {
209 return reinterpret_cast<const uint8_t *>(Data.getBufferStart());
210 }
211
212 // These functions are for SymbolRef to call internally. The main goal of
213 // this is to allow SymbolRef::SymbolPimpl to point directly to the symbol
214 // entry in the memory mapped object file. SymbolPimpl cannot contain any
215 // virtual functions because then it could not point into the memory mapped
216 // file.
217 //
218 // Implementations assume that the DataRefImpl is valid and has not been
219 // modified externally. It's UB otherwise.
220 friend class SymbolRef;
221
222 virtual Expected<StringRef> getSymbolName(DataRefImpl Symb) const = 0;
223 std::error_code printSymbolName(raw_ostream &OS,
224 DataRefImpl Symb) const override;
225 virtual Expected<uint64_t> getSymbolAddress(DataRefImpl Symb) const = 0;
226 virtual uint64_t getSymbolValueImpl(DataRefImpl Symb) const = 0;
227 virtual uint32_t getSymbolAlignment(DataRefImpl Symb) const;
228 virtual uint64_t getCommonSymbolSizeImpl(DataRefImpl Symb) const = 0;
229 virtual Expected<SymbolRef::Type> getSymbolType(DataRefImpl Symb) const = 0;
230 virtual Expected<section_iterator>
231 getSymbolSection(DataRefImpl Symb) const = 0;
232
233 // Same as above for SectionRef.
234 friend class SectionRef;
235
236 virtual void moveSectionNext(DataRefImpl &Sec) const = 0;
237 virtual std::error_code getSectionName(DataRefImpl Sec,
238 StringRef &Res) const = 0;
239 virtual uint64_t getSectionAddress(DataRefImpl Sec) const = 0;
240 virtual uint64_t getSectionIndex(DataRefImpl Sec) const = 0;
241 virtual uint64_t getSectionSize(DataRefImpl Sec) const = 0;
242 virtual std::error_code getSectionContents(DataRefImpl Sec,
243 StringRef &Res) const = 0;
244 virtual uint64_t getSectionAlignment(DataRefImpl Sec) const = 0;
245 virtual bool isSectionCompressed(DataRefImpl Sec) const = 0;
246 virtual bool isSectionText(DataRefImpl Sec) const = 0;
247 virtual bool isSectionData(DataRefImpl Sec) const = 0;
248 virtual bool isSectionBSS(DataRefImpl Sec) const = 0;
249 // A section is 'virtual' if its contents aren't present in the object image.
250 virtual bool isSectionVirtual(DataRefImpl Sec) const = 0;
251 virtual bool isSectionBitcode(DataRefImpl Sec) const;
252 virtual bool isSectionStripped(DataRefImpl Sec) const;
253 virtual bool isBerkeleyText(DataRefImpl Sec) const;
254 virtual bool isBerkeleyData(DataRefImpl Sec) const;
255 virtual relocation_iterator section_rel_begin(DataRefImpl Sec) const = 0;
256 virtual relocation_iterator section_rel_end(DataRefImpl Sec) const = 0;
257 virtual section_iterator getRelocatedSection(DataRefImpl Sec) const;
258
259 // Same as above for RelocationRef.
260 friend class RelocationRef;
261 virtual void moveRelocationNext(DataRefImpl &Rel) const = 0;
262 virtual uint64_t getRelocationOffset(DataRefImpl Rel) const = 0;
263 virtual symbol_iterator getRelocationSymbol(DataRefImpl Rel) const = 0;
264 virtual uint64_t getRelocationType(DataRefImpl Rel) const = 0;
265 virtual void getRelocationTypeName(DataRefImpl Rel,
266 SmallVectorImpl<char> &Result) const = 0;
267
268 uint64_t getSymbolValue(DataRefImpl Symb) const;
269
270public:
271 ObjectFile() = delete;
272 ObjectFile(const ObjectFile &other) = delete;
273
274 uint64_t getCommonSymbolSize(DataRefImpl Symb) const {
275 assert(getSymbolFlags(Symb) & SymbolRef::SF_Common);
276 return getCommonSymbolSizeImpl(Symb);
277 }
278
279 virtual std::vector<SectionRef> dynamic_relocation_sections() const {
280 return std::vector<SectionRef>();
281 }
282
283 using symbol_iterator_range = iterator_range<symbol_iterator>;
284 symbol_iterator_range symbols() const {
285 return symbol_iterator_range(symbol_begin(), symbol_end());
286 }
287
288 virtual section_iterator section_begin() const = 0;
289 virtual section_iterator section_end() const = 0;
290
291 using section_iterator_range = iterator_range<section_iterator>;
292 section_iterator_range sections() const {
293 return section_iterator_range(section_begin(), section_end());
294 }
295
296 /// The number of bytes used to represent an address in this object
297 /// file format.
298 virtual uint8_t getBytesInAddress() const = 0;
299
300 virtual StringRef getFileFormatName() const = 0;
301 virtual Triple::ArchType getArch() const = 0;
302 virtual SubtargetFeatures getFeatures() const = 0;
303 virtual void setARMSubArch(Triple &TheTriple) const { }
304 virtual Expected<uint64_t> getStartAddress() const {
305 return errorCodeToError(object_error::parse_failed);
306 };
307
308 /// Create a triple from the data in this object file.
309 Triple makeTriple() const;
310
311 virtual std::error_code
312 getBuildAttributes(ARMAttributeParser &Attributes) const {
313 return std::error_code();
314 }
315
316 /// Maps a debug section name to a standard DWARF section name.
317 virtual StringRef mapDebugSectionName(StringRef Name) const { return Name; }
318
319 /// True if this is a relocatable object (.o/.obj).
320 virtual bool isRelocatableObject() const = 0;
321
322 /// @returns Pointer to ObjectFile subclass to handle this type of object.
323 /// @param ObjectPath The path to the object file. ObjectPath.isObject must
324 /// return true.
325 /// Create ObjectFile from path.
326 static Expected<OwningBinary<ObjectFile>>
327 createObjectFile(StringRef ObjectPath);
328
329 static Expected<std::unique_ptr<ObjectFile>>
330 createObjectFile(MemoryBufferRef Object, llvm::file_magic Type);
331 static Expected<std::unique_ptr<ObjectFile>>
332 createObjectFile(MemoryBufferRef Object) {
333 return createObjectFile(Object, llvm::file_magic::unknown);
334 }
335
336 static bool classof(const Binary *v) {
337 return v->isObject();
338 }
339
340 static Expected<std::unique_ptr<COFFObjectFile>>
341 createCOFFObjectFile(MemoryBufferRef Object);
342
343 static Expected<std::unique_ptr<ObjectFile>>
344 createELFObjectFile(MemoryBufferRef Object);
345
346 static Expected<std::unique_ptr<MachOObjectFile>>
347 createMachOObjectFile(MemoryBufferRef Object,
348 uint32_t UniversalCputype = 0,
349 uint32_t UniversalIndex = 0);
350
351 static Expected<std::unique_ptr<WasmObjectFile>>
352 createWasmObjectFile(MemoryBufferRef Object);
353};
354
355// Inline function definitions.
356inline SymbolRef::SymbolRef(DataRefImpl SymbolP, const ObjectFile *Owner)
357 : BasicSymbolRef(SymbolP, Owner) {}
358
359inline Expected<StringRef> SymbolRef::getName() const {
360 return getObject()->getSymbolName(getRawDataRefImpl());
361}
362
363inline Expected<uint64_t> SymbolRef::getAddress() const {
364 return getObject()->getSymbolAddress(getRawDataRefImpl());
365}
366
367inline uint64_t SymbolRef::getValue() const {
368 return getObject()->getSymbolValue(getRawDataRefImpl());
369}
370
371inline uint32_t SymbolRef::getAlignment() const {
372 return getObject()->getSymbolAlignment(getRawDataRefImpl());
373}
374
375inline uint64_t SymbolRef::getCommonSize() const {
376 return getObject()->getCommonSymbolSize(getRawDataRefImpl());
377}
378
379inline Expected<section_iterator> SymbolRef::getSection() const {
380 return getObject()->getSymbolSection(getRawDataRefImpl());
381}
382
383inline Expected<SymbolRef::Type> SymbolRef::getType() const {
384 return getObject()->getSymbolType(getRawDataRefImpl());
385}
386
387inline const ObjectFile *SymbolRef::getObject() const {
388 const SymbolicFile *O = BasicSymbolRef::getObject();
389 return cast<ObjectFile>(O);
390}
391
392/// SectionRef
393inline SectionRef::SectionRef(DataRefImpl SectionP,
394 const ObjectFile *Owner)
395 : SectionPimpl(SectionP)
396 , OwningObject(Owner) {}
397
398inline bool SectionRef::operator==(const SectionRef &Other) const {
399 return SectionPimpl == Other.SectionPimpl;
400}
401
402inline bool SectionRef::operator!=(const SectionRef &Other) const {
403 return SectionPimpl != Other.SectionPimpl;
404}
405
406inline bool SectionRef::operator<(const SectionRef &Other) const {
407 return SectionPimpl < Other.SectionPimpl;
408}
409
410inline void SectionRef::moveNext() {
411 return OwningObject->moveSectionNext(SectionPimpl);
412}
413
414inline std::error_code SectionRef::getName(StringRef &Result) const {
415 return OwningObject->getSectionName(SectionPimpl, Result);
416}
417
418inline uint64_t SectionRef::getAddress() const {
419 return OwningObject->getSectionAddress(SectionPimpl);
420}
421
422inline uint64_t SectionRef::getIndex() const {
423 return OwningObject->getSectionIndex(SectionPimpl);
424}
425
426inline uint64_t SectionRef::getSize() const {
427 return OwningObject->getSectionSize(SectionPimpl);
428}
429
430inline std::error_code SectionRef::getContents(StringRef &Result) const {
431 return OwningObject->getSectionContents(SectionPimpl, Result);
432}
433
434inline uint64_t SectionRef::getAlignment() const {
435 return OwningObject->getSectionAlignment(SectionPimpl);
436}
437
438inline bool SectionRef::isCompressed() const {
439 return OwningObject->isSectionCompressed(SectionPimpl);
440}
441
442inline bool SectionRef::isText() const {
443 return OwningObject->isSectionText(SectionPimpl);
444}
445
446inline bool SectionRef::isData() const {
447 return OwningObject->isSectionData(SectionPimpl);
448}
449
450inline bool SectionRef::isBSS() const {
451 return OwningObject->isSectionBSS(SectionPimpl);
452}
453
454inline bool SectionRef::isVirtual() const {
455 return OwningObject->isSectionVirtual(SectionPimpl);
456}
457
458inline bool SectionRef::isBitcode() const {
459 return OwningObject->isSectionBitcode(SectionPimpl);
460}
461
462inline bool SectionRef::isStripped() const {
463 return OwningObject->isSectionStripped(SectionPimpl);
464}
465
466inline bool SectionRef::isBerkeleyText() const {
467 return OwningObject->isBerkeleyText(SectionPimpl);
468}
469
470inline bool SectionRef::isBerkeleyData() const {
471 return OwningObject->isBerkeleyData(SectionPimpl);
472}
473
474inline relocation_iterator SectionRef::relocation_begin() const {
475 return OwningObject->section_rel_begin(SectionPimpl);
476}
477
478inline relocation_iterator SectionRef::relocation_end() const {
479 return OwningObject->section_rel_end(SectionPimpl);
480}
481
482inline section_iterator SectionRef::getRelocatedSection() const {
483 return OwningObject->getRelocatedSection(SectionPimpl);
484}
485
486inline DataRefImpl SectionRef::getRawDataRefImpl() const {
487 return SectionPimpl;
488}
489
490inline const ObjectFile *SectionRef::getObject() const {
491 return OwningObject;
492}
493
494/// RelocationRef
495inline RelocationRef::RelocationRef(DataRefImpl RelocationP,
496 const ObjectFile *Owner)
497 : RelocationPimpl(RelocationP)
498 , OwningObject(Owner) {}
499
500inline bool RelocationRef::operator==(const RelocationRef &Other) const {
501 return RelocationPimpl == Other.RelocationPimpl;
502}
503
504inline void RelocationRef::moveNext() {
505 return OwningObject->moveRelocationNext(RelocationPimpl);
506}
507
508inline uint64_t RelocationRef::getOffset() const {
509 return OwningObject->getRelocationOffset(RelocationPimpl);
510}
511
512inline symbol_iterator RelocationRef::getSymbol() const {
513 return OwningObject->getRelocationSymbol(RelocationPimpl);
514}
515
516inline uint64_t RelocationRef::getType() const {
517 return OwningObject->getRelocationType(RelocationPimpl);
518}
519
520inline void RelocationRef::getTypeName(SmallVectorImpl<char> &Result) const {
521 return OwningObject->getRelocationTypeName(RelocationPimpl, Result);
522}
523
524inline DataRefImpl RelocationRef::getRawDataRefImpl() const {
525 return RelocationPimpl;
526}
527
528inline const ObjectFile *RelocationRef::getObject() const {
529 return OwningObject;
530}
531
532} // end namespace object
533
534} // end namespace llvm
535
536#endif // LLVM_OBJECT_OBJECTFILE_H
537