1 //===- ELF.cpp - ELF object file implementation ---------------------------===//
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 #include "llvm/Object/ELF.h"
10 #include "llvm/BinaryFormat/ELF.h"
11 #include "llvm/Support/LEB128.h"
12 
13 using namespace llvm;
14 using namespace object;
15 
16 #define STRINGIFY_ENUM_CASE(ns, name)                                          \
17   case ns::name:                                                               \
18     return #name;
19 
20 #define ELF_RELOC(name, value) STRINGIFY_ENUM_CASE(ELF, name)
21 
getELFRelocationTypeName(uint32_t Machine,uint32_t Type)22 StringRef llvm::object::getELFRelocationTypeName(uint32_t Machine,
23                                                  uint32_t Type) {
24   switch (Machine) {
25   case ELF::EM_X86_64:
26     switch (Type) {
27 #include "llvm/BinaryFormat/ELFRelocs/x86_64.def"
28     default:
29       break;
30     }
31     break;
32   case ELF::EM_386:
33   case ELF::EM_IAMCU:
34     switch (Type) {
35 #include "llvm/BinaryFormat/ELFRelocs/i386.def"
36     default:
37       break;
38     }
39     break;
40   case ELF::EM_MIPS:
41     switch (Type) {
42 #include "llvm/BinaryFormat/ELFRelocs/Mips.def"
43     default:
44       break;
45     }
46     break;
47   case ELF::EM_AARCH64:
48     switch (Type) {
49 #include "llvm/BinaryFormat/ELFRelocs/AArch64.def"
50     default:
51       break;
52     }
53     break;
54   case ELF::EM_ARM:
55     switch (Type) {
56 #include "llvm/BinaryFormat/ELFRelocs/ARM.def"
57     default:
58       break;
59     }
60     break;
61   case ELF::EM_ARC_COMPACT:
62   case ELF::EM_ARC_COMPACT2:
63     switch (Type) {
64 #include "llvm/BinaryFormat/ELFRelocs/ARC.def"
65     default:
66       break;
67     }
68     break;
69   case ELF::EM_AVR:
70     switch (Type) {
71 #include "llvm/BinaryFormat/ELFRelocs/AVR.def"
72     default:
73       break;
74     }
75     break;
76   case ELF::EM_HEXAGON:
77     switch (Type) {
78 #include "llvm/BinaryFormat/ELFRelocs/Hexagon.def"
79     default:
80       break;
81     }
82     break;
83   case ELF::EM_LANAI:
84     switch (Type) {
85 #include "llvm/BinaryFormat/ELFRelocs/Lanai.def"
86     default:
87       break;
88     }
89     break;
90   case ELF::EM_PPC:
91     switch (Type) {
92 #include "llvm/BinaryFormat/ELFRelocs/PowerPC.def"
93     default:
94       break;
95     }
96     break;
97   case ELF::EM_PPC64:
98     switch (Type) {
99 #include "llvm/BinaryFormat/ELFRelocs/PowerPC64.def"
100     default:
101       break;
102     }
103     break;
104   case ELF::EM_RISCV:
105     switch (Type) {
106 #include "llvm/BinaryFormat/ELFRelocs/RISCV.def"
107     default:
108       break;
109     }
110     break;
111   case ELF::EM_S390:
112     switch (Type) {
113 #include "llvm/BinaryFormat/ELFRelocs/SystemZ.def"
114     default:
115       break;
116     }
117     break;
118   case ELF::EM_SPARC:
119   case ELF::EM_SPARC32PLUS:
120   case ELF::EM_SPARCV9:
121     switch (Type) {
122 #include "llvm/BinaryFormat/ELFRelocs/Sparc.def"
123     default:
124       break;
125     }
126     break;
127   case ELF::EM_AMDGPU:
128     switch (Type) {
129 #include "llvm/BinaryFormat/ELFRelocs/AMDGPU.def"
130     default:
131       break;
132     }
133     break;
134   case ELF::EM_BPF:
135     switch (Type) {
136 #include "llvm/BinaryFormat/ELFRelocs/BPF.def"
137     default:
138       break;
139     }
140     break;
141   case ELF::EM_MSP430:
142     switch (Type) {
143 #include "llvm/BinaryFormat/ELFRelocs/MSP430.def"
144     default:
145       break;
146     }
147     break;
148   case ELF::EM_VE:
149     switch (Type) {
150 #include "llvm/BinaryFormat/ELFRelocs/VE.def"
151     default:
152       break;
153     }
154     break;
155   case ELF::EM_CSKY:
156     switch (Type) {
157 #include "llvm/BinaryFormat/ELFRelocs/CSKY.def"
158     default:
159       break;
160     }
161     break;
162   default:
163     break;
164   }
165   return "Unknown";
166 }
167 
168 #undef ELF_RELOC
169 
getELFRelativeRelocationType(uint32_t Machine)170 uint32_t llvm::object::getELFRelativeRelocationType(uint32_t Machine) {
171   switch (Machine) {
172   case ELF::EM_X86_64:
173     return ELF::R_X86_64_RELATIVE;
174   case ELF::EM_386:
175   case ELF::EM_IAMCU:
176     return ELF::R_386_RELATIVE;
177   case ELF::EM_MIPS:
178     break;
179   case ELF::EM_AARCH64:
180     return ELF::R_AARCH64_RELATIVE;
181   case ELF::EM_ARM:
182     return ELF::R_ARM_RELATIVE;
183   case ELF::EM_ARC_COMPACT:
184   case ELF::EM_ARC_COMPACT2:
185     return ELF::R_ARC_RELATIVE;
186   case ELF::EM_AVR:
187     break;
188   case ELF::EM_HEXAGON:
189     return ELF::R_HEX_RELATIVE;
190   case ELF::EM_LANAI:
191     break;
192   case ELF::EM_PPC:
193     break;
194   case ELF::EM_PPC64:
195     return ELF::R_PPC64_RELATIVE;
196   case ELF::EM_RISCV:
197     return ELF::R_RISCV_RELATIVE;
198   case ELF::EM_S390:
199     return ELF::R_390_RELATIVE;
200   case ELF::EM_SPARC:
201   case ELF::EM_SPARC32PLUS:
202   case ELF::EM_SPARCV9:
203     return ELF::R_SPARC_RELATIVE;
204   case ELF::EM_CSKY:
205     return ELF::R_CKCORE_RELATIVE;
206   case ELF::EM_AMDGPU:
207     break;
208   case ELF::EM_BPF:
209     break;
210   default:
211     break;
212   }
213   return 0;
214 }
215 
getELFSectionTypeName(uint32_t Machine,unsigned Type)216 StringRef llvm::object::getELFSectionTypeName(uint32_t Machine, unsigned Type) {
217   switch (Machine) {
218   case ELF::EM_ARM:
219     switch (Type) {
220       STRINGIFY_ENUM_CASE(ELF, SHT_ARM_EXIDX);
221       STRINGIFY_ENUM_CASE(ELF, SHT_ARM_PREEMPTMAP);
222       STRINGIFY_ENUM_CASE(ELF, SHT_ARM_ATTRIBUTES);
223       STRINGIFY_ENUM_CASE(ELF, SHT_ARM_DEBUGOVERLAY);
224       STRINGIFY_ENUM_CASE(ELF, SHT_ARM_OVERLAYSECTION);
225     }
226     break;
227   case ELF::EM_HEXAGON:
228     switch (Type) { STRINGIFY_ENUM_CASE(ELF, SHT_HEX_ORDERED); }
229     break;
230   case ELF::EM_X86_64:
231     switch (Type) { STRINGIFY_ENUM_CASE(ELF, SHT_X86_64_UNWIND); }
232     break;
233   case ELF::EM_MIPS:
234   case ELF::EM_MIPS_RS3_LE:
235     switch (Type) {
236       STRINGIFY_ENUM_CASE(ELF, SHT_MIPS_REGINFO);
237       STRINGIFY_ENUM_CASE(ELF, SHT_MIPS_OPTIONS);
238       STRINGIFY_ENUM_CASE(ELF, SHT_MIPS_DWARF);
239       STRINGIFY_ENUM_CASE(ELF, SHT_MIPS_ABIFLAGS);
240     }
241     break;
242   case ELF::EM_RISCV:
243     switch (Type) { STRINGIFY_ENUM_CASE(ELF, SHT_RISCV_ATTRIBUTES); }
244     break;
245   default:
246     break;
247   }
248 
249   switch (Type) {
250     STRINGIFY_ENUM_CASE(ELF, SHT_NULL);
251     STRINGIFY_ENUM_CASE(ELF, SHT_PROGBITS);
252     STRINGIFY_ENUM_CASE(ELF, SHT_SYMTAB);
253     STRINGIFY_ENUM_CASE(ELF, SHT_STRTAB);
254     STRINGIFY_ENUM_CASE(ELF, SHT_RELA);
255     STRINGIFY_ENUM_CASE(ELF, SHT_HASH);
256     STRINGIFY_ENUM_CASE(ELF, SHT_DYNAMIC);
257     STRINGIFY_ENUM_CASE(ELF, SHT_NOTE);
258     STRINGIFY_ENUM_CASE(ELF, SHT_NOBITS);
259     STRINGIFY_ENUM_CASE(ELF, SHT_REL);
260     STRINGIFY_ENUM_CASE(ELF, SHT_SHLIB);
261     STRINGIFY_ENUM_CASE(ELF, SHT_DYNSYM);
262     STRINGIFY_ENUM_CASE(ELF, SHT_INIT_ARRAY);
263     STRINGIFY_ENUM_CASE(ELF, SHT_FINI_ARRAY);
264     STRINGIFY_ENUM_CASE(ELF, SHT_PREINIT_ARRAY);
265     STRINGIFY_ENUM_CASE(ELF, SHT_GROUP);
266     STRINGIFY_ENUM_CASE(ELF, SHT_SYMTAB_SHNDX);
267     STRINGIFY_ENUM_CASE(ELF, SHT_RELR);
268     STRINGIFY_ENUM_CASE(ELF, SHT_ANDROID_REL);
269     STRINGIFY_ENUM_CASE(ELF, SHT_ANDROID_RELA);
270     STRINGIFY_ENUM_CASE(ELF, SHT_ANDROID_RELR);
271     STRINGIFY_ENUM_CASE(ELF, SHT_LLVM_ODRTAB);
272     STRINGIFY_ENUM_CASE(ELF, SHT_LLVM_LINKER_OPTIONS);
273     STRINGIFY_ENUM_CASE(ELF, SHT_LLVM_CALL_GRAPH_PROFILE);
274     STRINGIFY_ENUM_CASE(ELF, SHT_LLVM_ADDRSIG);
275     STRINGIFY_ENUM_CASE(ELF, SHT_LLVM_DEPENDENT_LIBRARIES);
276     STRINGIFY_ENUM_CASE(ELF, SHT_LLVM_SYMPART);
277     STRINGIFY_ENUM_CASE(ELF, SHT_LLVM_PART_EHDR);
278     STRINGIFY_ENUM_CASE(ELF, SHT_LLVM_PART_PHDR);
279     STRINGIFY_ENUM_CASE(ELF, SHT_LLVM_BB_ADDR_MAP);
280     STRINGIFY_ENUM_CASE(ELF, SHT_GNU_ATTRIBUTES);
281     STRINGIFY_ENUM_CASE(ELF, SHT_GNU_HASH);
282     STRINGIFY_ENUM_CASE(ELF, SHT_GNU_verdef);
283     STRINGIFY_ENUM_CASE(ELF, SHT_GNU_verneed);
284     STRINGIFY_ENUM_CASE(ELF, SHT_GNU_versym);
285   default:
286     return "Unknown";
287   }
288 }
289 
290 template <class ELFT>
291 std::vector<typename ELFT::Rel>
decode_relrs(Elf_Relr_Range relrs) const292 ELFFile<ELFT>::decode_relrs(Elf_Relr_Range relrs) const {
293   // This function decodes the contents of an SHT_RELR packed relocation
294   // section.
295   //
296   // Proposal for adding SHT_RELR sections to generic-abi is here:
297   //   https://groups.google.com/forum/#!topic/generic-abi/bX460iggiKg
298   //
299   // The encoded sequence of Elf64_Relr entries in a SHT_RELR section looks
300   // like [ AAAAAAAA BBBBBBB1 BBBBBBB1 ... AAAAAAAA BBBBBB1 ... ]
301   //
302   // i.e. start with an address, followed by any number of bitmaps. The address
303   // entry encodes 1 relocation. The subsequent bitmap entries encode up to 63
304   // relocations each, at subsequent offsets following the last address entry.
305   //
306   // The bitmap entries must have 1 in the least significant bit. The assumption
307   // here is that an address cannot have 1 in lsb. Odd addresses are not
308   // supported.
309   //
310   // Excluding the least significant bit in the bitmap, each non-zero bit in
311   // the bitmap represents a relocation to be applied to a corresponding machine
312   // word that follows the base address word. The second least significant bit
313   // represents the machine word immediately following the initial address, and
314   // each bit that follows represents the next word, in linear order. As such,
315   // a single bitmap can encode up to 31 relocations in a 32-bit object, and
316   // 63 relocations in a 64-bit object.
317   //
318   // This encoding has a couple of interesting properties:
319   // 1. Looking at any entry, it is clear whether it's an address or a bitmap:
320   //    even means address, odd means bitmap.
321   // 2. Just a simple list of addresses is a valid encoding.
322 
323   Elf_Rel Rel;
324   Rel.r_info = 0;
325   Rel.setType(getRelativeRelocationType(), false);
326   std::vector<Elf_Rel> Relocs;
327 
328   // Word type: uint32_t for Elf32, and uint64_t for Elf64.
329   typedef typename ELFT::uint Word;
330 
331   // Word size in number of bytes.
332   const size_t WordSize = sizeof(Word);
333 
334   // Number of bits used for the relocation offsets bitmap.
335   // These many relative relocations can be encoded in a single entry.
336   const size_t NBits = 8*WordSize - 1;
337 
338   Word Base = 0;
339   for (const Elf_Relr &R : relrs) {
340     Word Entry = R;
341     if ((Entry&1) == 0) {
342       // Even entry: encodes the offset for next relocation.
343       Rel.r_offset = Entry;
344       Relocs.push_back(Rel);
345       // Set base offset for subsequent bitmap entries.
346       Base = Entry + WordSize;
347       continue;
348     }
349 
350     // Odd entry: encodes bitmap for relocations starting at base.
351     Word Offset = Base;
352     while (Entry != 0) {
353       Entry >>= 1;
354       if ((Entry&1) != 0) {
355         Rel.r_offset = Offset;
356         Relocs.push_back(Rel);
357       }
358       Offset += WordSize;
359     }
360 
361     // Advance base offset by NBits words.
362     Base += NBits * WordSize;
363   }
364 
365   return Relocs;
366 }
367 
368 template <class ELFT>
369 Expected<std::vector<typename ELFT::Rela>>
android_relas(const Elf_Shdr & Sec) const370 ELFFile<ELFT>::android_relas(const Elf_Shdr &Sec) const {
371   // This function reads relocations in Android's packed relocation format,
372   // which is based on SLEB128 and delta encoding.
373   Expected<ArrayRef<uint8_t>> ContentsOrErr = getSectionContents(Sec);
374   if (!ContentsOrErr)
375     return ContentsOrErr.takeError();
376   const uint8_t *Cur = ContentsOrErr->begin();
377   const uint8_t *End = ContentsOrErr->end();
378   if (ContentsOrErr->size() < 4 || Cur[0] != 'A' || Cur[1] != 'P' ||
379       Cur[2] != 'S' || Cur[3] != '2')
380     return createError("invalid packed relocation header");
381   Cur += 4;
382 
383   const char *ErrStr = nullptr;
384   auto ReadSLEB = [&]() -> int64_t {
385     if (ErrStr)
386       return 0;
387     unsigned Len;
388     int64_t Result = decodeSLEB128(Cur, &Len, End, &ErrStr);
389     Cur += Len;
390     return Result;
391   };
392 
393   uint64_t NumRelocs = ReadSLEB();
394   uint64_t Offset = ReadSLEB();
395   uint64_t Addend = 0;
396 
397   if (ErrStr)
398     return createError(ErrStr);
399 
400   std::vector<Elf_Rela> Relocs;
401   Relocs.reserve(NumRelocs);
402   while (NumRelocs) {
403     uint64_t NumRelocsInGroup = ReadSLEB();
404     if (NumRelocsInGroup > NumRelocs)
405       return createError("relocation group unexpectedly large");
406     NumRelocs -= NumRelocsInGroup;
407 
408     uint64_t GroupFlags = ReadSLEB();
409     bool GroupedByInfo = GroupFlags & ELF::RELOCATION_GROUPED_BY_INFO_FLAG;
410     bool GroupedByOffsetDelta = GroupFlags & ELF::RELOCATION_GROUPED_BY_OFFSET_DELTA_FLAG;
411     bool GroupedByAddend = GroupFlags & ELF::RELOCATION_GROUPED_BY_ADDEND_FLAG;
412     bool GroupHasAddend = GroupFlags & ELF::RELOCATION_GROUP_HAS_ADDEND_FLAG;
413 
414     uint64_t GroupOffsetDelta;
415     if (GroupedByOffsetDelta)
416       GroupOffsetDelta = ReadSLEB();
417 
418     uint64_t GroupRInfo;
419     if (GroupedByInfo)
420       GroupRInfo = ReadSLEB();
421 
422     if (GroupedByAddend && GroupHasAddend)
423       Addend += ReadSLEB();
424 
425     if (!GroupHasAddend)
426       Addend = 0;
427 
428     for (uint64_t I = 0; I != NumRelocsInGroup; ++I) {
429       Elf_Rela R;
430       Offset += GroupedByOffsetDelta ? GroupOffsetDelta : ReadSLEB();
431       R.r_offset = Offset;
432       R.r_info = GroupedByInfo ? GroupRInfo : ReadSLEB();
433       if (GroupHasAddend && !GroupedByAddend)
434         Addend += ReadSLEB();
435       R.r_addend = Addend;
436       Relocs.push_back(R);
437 
438       if (ErrStr)
439         return createError(ErrStr);
440     }
441 
442     if (ErrStr)
443       return createError(ErrStr);
444   }
445 
446   return Relocs;
447 }
448 
449 template <class ELFT>
getDynamicTagAsString(unsigned Arch,uint64_t Type) const450 std::string ELFFile<ELFT>::getDynamicTagAsString(unsigned Arch,
451                                                  uint64_t Type) const {
452 #define DYNAMIC_STRINGIFY_ENUM(tag, value)                                     \
453   case value:                                                                  \
454     return #tag;
455 
456 #define DYNAMIC_TAG(n, v)
457   switch (Arch) {
458   case ELF::EM_AARCH64:
459     switch (Type) {
460 #define AARCH64_DYNAMIC_TAG(name, value) DYNAMIC_STRINGIFY_ENUM(name, value)
461 #include "llvm/BinaryFormat/DynamicTags.def"
462 #undef AARCH64_DYNAMIC_TAG
463     }
464     break;
465 
466   case ELF::EM_HEXAGON:
467     switch (Type) {
468 #define HEXAGON_DYNAMIC_TAG(name, value) DYNAMIC_STRINGIFY_ENUM(name, value)
469 #include "llvm/BinaryFormat/DynamicTags.def"
470 #undef HEXAGON_DYNAMIC_TAG
471     }
472     break;
473 
474   case ELF::EM_MIPS:
475     switch (Type) {
476 #define MIPS_DYNAMIC_TAG(name, value) DYNAMIC_STRINGIFY_ENUM(name, value)
477 #include "llvm/BinaryFormat/DynamicTags.def"
478 #undef MIPS_DYNAMIC_TAG
479     }
480     break;
481 
482   case ELF::EM_PPC64:
483     switch (Type) {
484 #define PPC64_DYNAMIC_TAG(name, value) DYNAMIC_STRINGIFY_ENUM(name, value)
485 #include "llvm/BinaryFormat/DynamicTags.def"
486 #undef PPC64_DYNAMIC_TAG
487     }
488     break;
489   }
490 #undef DYNAMIC_TAG
491   switch (Type) {
492 // Now handle all dynamic tags except the architecture specific ones
493 #define AARCH64_DYNAMIC_TAG(name, value)
494 #define MIPS_DYNAMIC_TAG(name, value)
495 #define HEXAGON_DYNAMIC_TAG(name, value)
496 #define PPC64_DYNAMIC_TAG(name, value)
497 // Also ignore marker tags such as DT_HIOS (maps to DT_VERNEEDNUM), etc.
498 #define DYNAMIC_TAG_MARKER(name, value)
499 #define DYNAMIC_TAG(name, value) case value: return #name;
500 #include "llvm/BinaryFormat/DynamicTags.def"
501 #undef DYNAMIC_TAG
502 #undef AARCH64_DYNAMIC_TAG
503 #undef MIPS_DYNAMIC_TAG
504 #undef HEXAGON_DYNAMIC_TAG
505 #undef PPC64_DYNAMIC_TAG
506 #undef DYNAMIC_TAG_MARKER
507 #undef DYNAMIC_STRINGIFY_ENUM
508   default:
509     return "<unknown:>0x" + utohexstr(Type, true);
510   }
511 }
512 
513 template <class ELFT>
getDynamicTagAsString(uint64_t Type) const514 std::string ELFFile<ELFT>::getDynamicTagAsString(uint64_t Type) const {
515   return getDynamicTagAsString(getHeader().e_machine, Type);
516 }
517 
518 template <class ELFT>
dynamicEntries() const519 Expected<typename ELFT::DynRange> ELFFile<ELFT>::dynamicEntries() const {
520   ArrayRef<Elf_Dyn> Dyn;
521 
522   auto ProgramHeadersOrError = program_headers();
523   if (!ProgramHeadersOrError)
524     return ProgramHeadersOrError.takeError();
525 
526   for (const Elf_Phdr &Phdr : *ProgramHeadersOrError) {
527     if (Phdr.p_type == ELF::PT_DYNAMIC) {
528       Dyn = makeArrayRef(
529           reinterpret_cast<const Elf_Dyn *>(base() + Phdr.p_offset),
530           Phdr.p_filesz / sizeof(Elf_Dyn));
531       break;
532     }
533   }
534 
535   // If we can't find the dynamic section in the program headers, we just fall
536   // back on the sections.
537   if (Dyn.empty()) {
538     auto SectionsOrError = sections();
539     if (!SectionsOrError)
540       return SectionsOrError.takeError();
541 
542     for (const Elf_Shdr &Sec : *SectionsOrError) {
543       if (Sec.sh_type == ELF::SHT_DYNAMIC) {
544         Expected<ArrayRef<Elf_Dyn>> DynOrError =
545             getSectionContentsAsArray<Elf_Dyn>(Sec);
546         if (!DynOrError)
547           return DynOrError.takeError();
548         Dyn = *DynOrError;
549         break;
550       }
551     }
552 
553     if (!Dyn.data())
554       return ArrayRef<Elf_Dyn>();
555   }
556 
557   if (Dyn.empty())
558     // TODO: this error is untested.
559     return createError("invalid empty dynamic section");
560 
561   if (Dyn.back().d_tag != ELF::DT_NULL)
562     // TODO: this error is untested.
563     return createError("dynamic sections must be DT_NULL terminated");
564 
565   return Dyn;
566 }
567 
568 template <class ELFT>
569 Expected<const uint8_t *>
toMappedAddr(uint64_t VAddr,WarningHandler WarnHandler) const570 ELFFile<ELFT>::toMappedAddr(uint64_t VAddr, WarningHandler WarnHandler) const {
571   auto ProgramHeadersOrError = program_headers();
572   if (!ProgramHeadersOrError)
573     return ProgramHeadersOrError.takeError();
574 
575   llvm::SmallVector<Elf_Phdr *, 4> LoadSegments;
576 
577   for (const Elf_Phdr &Phdr : *ProgramHeadersOrError)
578     if (Phdr.p_type == ELF::PT_LOAD)
579       LoadSegments.push_back(const_cast<Elf_Phdr *>(&Phdr));
580 
581   auto SortPred = [](const Elf_Phdr_Impl<ELFT> *A,
582                      const Elf_Phdr_Impl<ELFT> *B) {
583     return A->p_vaddr < B->p_vaddr;
584   };
585   if (!llvm::is_sorted(LoadSegments, SortPred)) {
586     if (Error E =
587             WarnHandler("loadable segments are unsorted by virtual address"))
588       return std::move(E);
589     llvm::stable_sort(LoadSegments, SortPred);
590   }
591 
592   const Elf_Phdr *const *I = llvm::upper_bound(
593       LoadSegments, VAddr, [](uint64_t VAddr, const Elf_Phdr_Impl<ELFT> *Phdr) {
594         return VAddr < Phdr->p_vaddr;
595       });
596 
597   if (I == LoadSegments.begin())
598     return createError("virtual address is not in any segment: 0x" +
599                        Twine::utohexstr(VAddr));
600   --I;
601   const Elf_Phdr &Phdr = **I;
602   uint64_t Delta = VAddr - Phdr.p_vaddr;
603   if (Delta >= Phdr.p_filesz)
604     return createError("virtual address is not in any segment: 0x" +
605                        Twine::utohexstr(VAddr));
606 
607   uint64_t Offset = Phdr.p_offset + Delta;
608   if (Offset >= getBufSize())
609     return createError("can't map virtual address 0x" +
610                        Twine::utohexstr(VAddr) + " to the segment with index " +
611                        Twine(&Phdr - (*ProgramHeadersOrError).data() + 1) +
612                        ": the segment ends at 0x" +
613                        Twine::utohexstr(Phdr.p_offset + Phdr.p_filesz) +
614                        ", which is greater than the file size (0x" +
615                        Twine::utohexstr(getBufSize()) + ")");
616 
617   return base() + Offset;
618 }
619 
620 template class llvm::object::ELFFile<ELF32LE>;
621 template class llvm::object::ELFFile<ELF32BE>;
622 template class llvm::object::ELFFile<ELF64LE>;
623 template class llvm::object::ELFFile<ELF64BE>;
624