xref: /llvm-project/llvm/lib/Object/COFFObjectFile.cpp (revision 19f2f67928650c998202a8b6ae14fd1091f43bf5)
1 //===- COFFObjectFile.cpp - COFF 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 // This file declares the COFFObjectFile class.
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #include "llvm/ADT/ArrayRef.h"
14 #include "llvm/ADT/StringRef.h"
15 #include "llvm/ADT/StringSwitch.h"
16 #include "llvm/ADT/iterator_range.h"
17 #include "llvm/Object/Binary.h"
18 #include "llvm/Object/COFF.h"
19 #include "llvm/Object/Error.h"
20 #include "llvm/Object/ObjectFile.h"
21 #include "llvm/Object/WindowsMachineFlag.h"
22 #include "llvm/Support/BinaryStreamReader.h"
23 #include "llvm/Support/Endian.h"
24 #include "llvm/Support/Error.h"
25 #include "llvm/Support/ErrorHandling.h"
26 #include "llvm/Support/MathExtras.h"
27 #include "llvm/Support/MemoryBufferRef.h"
28 #include <algorithm>
29 #include <cassert>
30 #include <cinttypes>
31 #include <cstddef>
32 #include <cstring>
33 #include <limits>
34 #include <memory>
35 #include <system_error>
36 
37 using namespace llvm;
38 using namespace object;
39 
40 using support::ulittle16_t;
41 using support::ulittle32_t;
42 using support::ulittle64_t;
43 using support::little16_t;
44 
45 // Returns false if size is greater than the buffer size. And sets ec.
46 static bool checkSize(MemoryBufferRef M, std::error_code &EC, uint64_t Size) {
47   if (M.getBufferSize() < Size) {
48     EC = object_error::unexpected_eof;
49     return false;
50   }
51   return true;
52 }
53 
54 // Sets Obj unless any bytes in [addr, addr + size) fall outsize of m.
55 // Returns unexpected_eof if error.
56 template <typename T>
57 static Error getObject(const T *&Obj, MemoryBufferRef M, const void *Ptr,
58                        const uint64_t Size = sizeof(T)) {
59   uintptr_t Addr = reinterpret_cast<uintptr_t>(Ptr);
60   if (Error E = Binary::checkOffset(M, Addr, Size))
61     return E;
62   Obj = reinterpret_cast<const T *>(Addr);
63   return Error::success();
64 }
65 
66 // Decode a string table entry in base 64 (//AAAAAA). Expects \arg Str without
67 // prefixed slashes.
68 static bool decodeBase64StringEntry(StringRef Str, uint32_t &Result) {
69   assert(Str.size() <= 6 && "String too long, possible overflow.");
70   if (Str.size() > 6)
71     return true;
72 
73   uint64_t Value = 0;
74   while (!Str.empty()) {
75     unsigned CharVal;
76     if (Str[0] >= 'A' && Str[0] <= 'Z') // 0..25
77       CharVal = Str[0] - 'A';
78     else if (Str[0] >= 'a' && Str[0] <= 'z') // 26..51
79       CharVal = Str[0] - 'a' + 26;
80     else if (Str[0] >= '0' && Str[0] <= '9') // 52..61
81       CharVal = Str[0] - '0' + 52;
82     else if (Str[0] == '+') // 62
83       CharVal = 62;
84     else if (Str[0] == '/') // 63
85       CharVal = 63;
86     else
87       return true;
88 
89     Value = (Value * 64) + CharVal;
90     Str = Str.substr(1);
91   }
92 
93   if (Value > std::numeric_limits<uint32_t>::max())
94     return true;
95 
96   Result = static_cast<uint32_t>(Value);
97   return false;
98 }
99 
100 template <typename coff_symbol_type>
101 const coff_symbol_type *COFFObjectFile::toSymb(DataRefImpl Ref) const {
102   const coff_symbol_type *Addr =
103       reinterpret_cast<const coff_symbol_type *>(Ref.p);
104 
105   assert(!checkOffset(Data, reinterpret_cast<uintptr_t>(Addr), sizeof(*Addr)));
106 #ifndef NDEBUG
107   // Verify that the symbol points to a valid entry in the symbol table.
108   uintptr_t Offset =
109       reinterpret_cast<uintptr_t>(Addr) - reinterpret_cast<uintptr_t>(base());
110 
111   assert((Offset - getPointerToSymbolTable()) % sizeof(coff_symbol_type) == 0 &&
112          "Symbol did not point to the beginning of a symbol");
113 #endif
114 
115   return Addr;
116 }
117 
118 const coff_section *COFFObjectFile::toSec(DataRefImpl Ref) const {
119   const coff_section *Addr = reinterpret_cast<const coff_section*>(Ref.p);
120 
121 #ifndef NDEBUG
122   // Verify that the section points to a valid entry in the section table.
123   if (Addr < SectionTable || Addr >= (SectionTable + getNumberOfSections()))
124     report_fatal_error("Section was outside of section table.");
125 
126   uintptr_t Offset = reinterpret_cast<uintptr_t>(Addr) -
127                      reinterpret_cast<uintptr_t>(SectionTable);
128   assert(Offset % sizeof(coff_section) == 0 &&
129          "Section did not point to the beginning of a section");
130 #endif
131 
132   return Addr;
133 }
134 
135 void COFFObjectFile::moveSymbolNext(DataRefImpl &Ref) const {
136   auto End = reinterpret_cast<uintptr_t>(StringTable);
137   if (SymbolTable16) {
138     const coff_symbol16 *Symb = toSymb<coff_symbol16>(Ref);
139     Symb += 1 + Symb->NumberOfAuxSymbols;
140     Ref.p = std::min(reinterpret_cast<uintptr_t>(Symb), End);
141   } else if (SymbolTable32) {
142     const coff_symbol32 *Symb = toSymb<coff_symbol32>(Ref);
143     Symb += 1 + Symb->NumberOfAuxSymbols;
144     Ref.p = std::min(reinterpret_cast<uintptr_t>(Symb), End);
145   } else {
146     llvm_unreachable("no symbol table pointer!");
147   }
148 }
149 
150 Expected<StringRef> COFFObjectFile::getSymbolName(DataRefImpl Ref) const {
151   return getSymbolName(getCOFFSymbol(Ref));
152 }
153 
154 uint64_t COFFObjectFile::getSymbolValueImpl(DataRefImpl Ref) const {
155   return getCOFFSymbol(Ref).getValue();
156 }
157 
158 uint32_t COFFObjectFile::getSymbolAlignment(DataRefImpl Ref) const {
159   // MSVC/link.exe seems to align symbols to the next-power-of-2
160   // up to 32 bytes.
161   COFFSymbolRef Symb = getCOFFSymbol(Ref);
162   return std::min(uint64_t(32), PowerOf2Ceil(Symb.getValue()));
163 }
164 
165 Expected<uint64_t> COFFObjectFile::getSymbolAddress(DataRefImpl Ref) const {
166   uint64_t Result = cantFail(getSymbolValue(Ref));
167   COFFSymbolRef Symb = getCOFFSymbol(Ref);
168   int32_t SectionNumber = Symb.getSectionNumber();
169 
170   if (Symb.isAnyUndefined() || Symb.isCommon() ||
171       COFF::isReservedSectionNumber(SectionNumber))
172     return Result;
173 
174   Expected<const coff_section *> Section = getSection(SectionNumber);
175   if (!Section)
176     return Section.takeError();
177   Result += (*Section)->VirtualAddress;
178 
179   // The section VirtualAddress does not include ImageBase, and we want to
180   // return virtual addresses.
181   Result += getImageBase();
182 
183   return Result;
184 }
185 
186 Expected<SymbolRef::Type> COFFObjectFile::getSymbolType(DataRefImpl Ref) const {
187   COFFSymbolRef Symb = getCOFFSymbol(Ref);
188   int32_t SectionNumber = Symb.getSectionNumber();
189 
190   if (Symb.getComplexType() == COFF::IMAGE_SYM_DTYPE_FUNCTION)
191     return SymbolRef::ST_Function;
192   if (Symb.isAnyUndefined())
193     return SymbolRef::ST_Unknown;
194   if (Symb.isCommon())
195     return SymbolRef::ST_Data;
196   if (Symb.isFileRecord())
197     return SymbolRef::ST_File;
198 
199   // TODO: perhaps we need a new symbol type ST_Section.
200   if (SectionNumber == COFF::IMAGE_SYM_DEBUG || Symb.isSectionDefinition())
201     return SymbolRef::ST_Debug;
202 
203   if (!COFF::isReservedSectionNumber(SectionNumber))
204     return SymbolRef::ST_Data;
205 
206   return SymbolRef::ST_Other;
207 }
208 
209 Expected<uint32_t> COFFObjectFile::getSymbolFlags(DataRefImpl Ref) const {
210   COFFSymbolRef Symb = getCOFFSymbol(Ref);
211   uint32_t Result = SymbolRef::SF_None;
212 
213   if (Symb.isExternal() || Symb.isWeakExternal())
214     Result |= SymbolRef::SF_Global;
215 
216   if (const coff_aux_weak_external *AWE = Symb.getWeakExternal()) {
217     Result |= SymbolRef::SF_Weak;
218     if (AWE->Characteristics != COFF::IMAGE_WEAK_EXTERN_SEARCH_ALIAS)
219       Result |= SymbolRef::SF_Undefined;
220   }
221 
222   if (Symb.getSectionNumber() == COFF::IMAGE_SYM_ABSOLUTE)
223     Result |= SymbolRef::SF_Absolute;
224 
225   if (Symb.isFileRecord())
226     Result |= SymbolRef::SF_FormatSpecific;
227 
228   if (Symb.isSectionDefinition())
229     Result |= SymbolRef::SF_FormatSpecific;
230 
231   if (Symb.isCommon())
232     Result |= SymbolRef::SF_Common;
233 
234   if (Symb.isUndefined())
235     Result |= SymbolRef::SF_Undefined;
236 
237   return Result;
238 }
239 
240 uint64_t COFFObjectFile::getCommonSymbolSizeImpl(DataRefImpl Ref) const {
241   COFFSymbolRef Symb = getCOFFSymbol(Ref);
242   return Symb.getValue();
243 }
244 
245 Expected<section_iterator>
246 COFFObjectFile::getSymbolSection(DataRefImpl Ref) const {
247   COFFSymbolRef Symb = getCOFFSymbol(Ref);
248   if (COFF::isReservedSectionNumber(Symb.getSectionNumber()))
249     return section_end();
250   Expected<const coff_section *> Sec = getSection(Symb.getSectionNumber());
251   if (!Sec)
252     return Sec.takeError();
253   DataRefImpl Ret;
254   Ret.p = reinterpret_cast<uintptr_t>(*Sec);
255   return section_iterator(SectionRef(Ret, this));
256 }
257 
258 unsigned COFFObjectFile::getSymbolSectionID(SymbolRef Sym) const {
259   COFFSymbolRef Symb = getCOFFSymbol(Sym.getRawDataRefImpl());
260   return Symb.getSectionNumber();
261 }
262 
263 void COFFObjectFile::moveSectionNext(DataRefImpl &Ref) const {
264   const coff_section *Sec = toSec(Ref);
265   Sec += 1;
266   Ref.p = reinterpret_cast<uintptr_t>(Sec);
267 }
268 
269 Expected<StringRef> COFFObjectFile::getSectionName(DataRefImpl Ref) const {
270   const coff_section *Sec = toSec(Ref);
271   return getSectionName(Sec);
272 }
273 
274 uint64_t COFFObjectFile::getSectionAddress(DataRefImpl Ref) const {
275   const coff_section *Sec = toSec(Ref);
276   uint64_t Result = Sec->VirtualAddress;
277 
278   // The section VirtualAddress does not include ImageBase, and we want to
279   // return virtual addresses.
280   Result += getImageBase();
281   return Result;
282 }
283 
284 uint64_t COFFObjectFile::getSectionIndex(DataRefImpl Sec) const {
285   return toSec(Sec) - SectionTable;
286 }
287 
288 uint64_t COFFObjectFile::getSectionSize(DataRefImpl Ref) const {
289   return getSectionSize(toSec(Ref));
290 }
291 
292 Expected<ArrayRef<uint8_t>>
293 COFFObjectFile::getSectionContents(DataRefImpl Ref) const {
294   const coff_section *Sec = toSec(Ref);
295   ArrayRef<uint8_t> Res;
296   if (Error E = getSectionContents(Sec, Res))
297     return E;
298   return Res;
299 }
300 
301 uint64_t COFFObjectFile::getSectionAlignment(DataRefImpl Ref) const {
302   const coff_section *Sec = toSec(Ref);
303   return Sec->getAlignment();
304 }
305 
306 bool COFFObjectFile::isSectionCompressed(DataRefImpl Sec) const {
307   return false;
308 }
309 
310 bool COFFObjectFile::isSectionText(DataRefImpl Ref) const {
311   const coff_section *Sec = toSec(Ref);
312   return Sec->Characteristics & COFF::IMAGE_SCN_CNT_CODE;
313 }
314 
315 bool COFFObjectFile::isSectionData(DataRefImpl Ref) const {
316   const coff_section *Sec = toSec(Ref);
317   return Sec->Characteristics & COFF::IMAGE_SCN_CNT_INITIALIZED_DATA;
318 }
319 
320 bool COFFObjectFile::isSectionBSS(DataRefImpl Ref) const {
321   const coff_section *Sec = toSec(Ref);
322   const uint32_t BssFlags = COFF::IMAGE_SCN_CNT_UNINITIALIZED_DATA |
323                             COFF::IMAGE_SCN_MEM_READ |
324                             COFF::IMAGE_SCN_MEM_WRITE;
325   return (Sec->Characteristics & BssFlags) == BssFlags;
326 }
327 
328 // The .debug sections are the only debug sections for COFF
329 // (\see MCObjectFileInfo.cpp).
330 bool COFFObjectFile::isDebugSection(DataRefImpl Ref) const {
331   Expected<StringRef> SectionNameOrErr = getSectionName(Ref);
332   if (!SectionNameOrErr) {
333     // TODO: Report the error message properly.
334     consumeError(SectionNameOrErr.takeError());
335     return false;
336   }
337   StringRef SectionName = SectionNameOrErr.get();
338   return SectionName.starts_with(".debug");
339 }
340 
341 unsigned COFFObjectFile::getSectionID(SectionRef Sec) const {
342   uintptr_t Offset =
343       Sec.getRawDataRefImpl().p - reinterpret_cast<uintptr_t>(SectionTable);
344   assert((Offset % sizeof(coff_section)) == 0);
345   return (Offset / sizeof(coff_section)) + 1;
346 }
347 
348 bool COFFObjectFile::isSectionVirtual(DataRefImpl Ref) const {
349   const coff_section *Sec = toSec(Ref);
350   // In COFF, a virtual section won't have any in-file
351   // content, so the file pointer to the content will be zero.
352   return Sec->PointerToRawData == 0;
353 }
354 
355 static uint32_t getNumberOfRelocations(const coff_section *Sec,
356                                        MemoryBufferRef M, const uint8_t *base) {
357   // The field for the number of relocations in COFF section table is only
358   // 16-bit wide. If a section has more than 65535 relocations, 0xFFFF is set to
359   // NumberOfRelocations field, and the actual relocation count is stored in the
360   // VirtualAddress field in the first relocation entry.
361   if (Sec->hasExtendedRelocations()) {
362     const coff_relocation *FirstReloc;
363     if (Error E = getObject(FirstReloc, M,
364                             reinterpret_cast<const coff_relocation *>(
365                                 base + Sec->PointerToRelocations))) {
366       consumeError(std::move(E));
367       return 0;
368     }
369     // -1 to exclude this first relocation entry.
370     return FirstReloc->VirtualAddress - 1;
371   }
372   return Sec->NumberOfRelocations;
373 }
374 
375 static const coff_relocation *
376 getFirstReloc(const coff_section *Sec, MemoryBufferRef M, const uint8_t *Base) {
377   uint64_t NumRelocs = getNumberOfRelocations(Sec, M, Base);
378   if (!NumRelocs)
379     return nullptr;
380   auto begin = reinterpret_cast<const coff_relocation *>(
381       Base + Sec->PointerToRelocations);
382   if (Sec->hasExtendedRelocations()) {
383     // Skip the first relocation entry repurposed to store the number of
384     // relocations.
385     begin++;
386   }
387   if (auto E = Binary::checkOffset(M, reinterpret_cast<uintptr_t>(begin),
388                                    sizeof(coff_relocation) * NumRelocs)) {
389     consumeError(std::move(E));
390     return nullptr;
391   }
392   return begin;
393 }
394 
395 relocation_iterator COFFObjectFile::section_rel_begin(DataRefImpl Ref) const {
396   const coff_section *Sec = toSec(Ref);
397   const coff_relocation *begin = getFirstReloc(Sec, Data, base());
398   if (begin && Sec->VirtualAddress != 0)
399     report_fatal_error("Sections with relocations should have an address of 0");
400   DataRefImpl Ret;
401   Ret.p = reinterpret_cast<uintptr_t>(begin);
402   return relocation_iterator(RelocationRef(Ret, this));
403 }
404 
405 relocation_iterator COFFObjectFile::section_rel_end(DataRefImpl Ref) const {
406   const coff_section *Sec = toSec(Ref);
407   const coff_relocation *I = getFirstReloc(Sec, Data, base());
408   if (I)
409     I += getNumberOfRelocations(Sec, Data, base());
410   DataRefImpl Ret;
411   Ret.p = reinterpret_cast<uintptr_t>(I);
412   return relocation_iterator(RelocationRef(Ret, this));
413 }
414 
415 // Initialize the pointer to the symbol table.
416 Error COFFObjectFile::initSymbolTablePtr() {
417   if (COFFHeader)
418     if (Error E = getObject(
419             SymbolTable16, Data, base() + getPointerToSymbolTable(),
420             (uint64_t)getNumberOfSymbols() * getSymbolTableEntrySize()))
421       return E;
422 
423   if (COFFBigObjHeader)
424     if (Error E = getObject(
425             SymbolTable32, Data, base() + getPointerToSymbolTable(),
426             (uint64_t)getNumberOfSymbols() * getSymbolTableEntrySize()))
427       return E;
428 
429   // Find string table. The first four byte of the string table contains the
430   // total size of the string table, including the size field itself. If the
431   // string table is empty, the value of the first four byte would be 4.
432   uint32_t StringTableOffset = getPointerToSymbolTable() +
433                                getNumberOfSymbols() * getSymbolTableEntrySize();
434   const uint8_t *StringTableAddr = base() + StringTableOffset;
435   const ulittle32_t *StringTableSizePtr;
436   if (Error E = getObject(StringTableSizePtr, Data, StringTableAddr))
437     return E;
438   StringTableSize = *StringTableSizePtr;
439   if (Error E = getObject(StringTable, Data, StringTableAddr, StringTableSize))
440     return E;
441 
442   // Treat table sizes < 4 as empty because contrary to the PECOFF spec, some
443   // tools like cvtres write a size of 0 for an empty table instead of 4.
444   if (StringTableSize < 4)
445     StringTableSize = 4;
446 
447   // Check that the string table is null terminated if has any in it.
448   if (StringTableSize > 4 && StringTable[StringTableSize - 1] != 0)
449     return createStringError(object_error::parse_failed,
450                              "string table missing null terminator");
451   return Error::success();
452 }
453 
454 uint64_t COFFObjectFile::getImageBase() const {
455   if (PE32Header)
456     return PE32Header->ImageBase;
457   else if (PE32PlusHeader)
458     return PE32PlusHeader->ImageBase;
459   // This actually comes up in practice.
460   return 0;
461 }
462 
463 // Returns the file offset for the given VA.
464 Error COFFObjectFile::getVaPtr(uint64_t Addr, uintptr_t &Res) const {
465   uint64_t ImageBase = getImageBase();
466   uint64_t Rva = Addr - ImageBase;
467   assert(Rva <= UINT32_MAX);
468   return getRvaPtr((uint32_t)Rva, Res);
469 }
470 
471 // Returns the file offset for the given RVA.
472 Error COFFObjectFile::getRvaPtr(uint32_t Addr, uintptr_t &Res,
473                                 const char *ErrorContext) const {
474   for (const SectionRef &S : sections()) {
475     const coff_section *Section = getCOFFSection(S);
476     uint32_t SectionStart = Section->VirtualAddress;
477     uint32_t SectionEnd = Section->VirtualAddress + Section->VirtualSize;
478     if (SectionStart <= Addr && Addr < SectionEnd) {
479       // A table/directory entry can be pointing to somewhere in a stripped
480       // section, in an object that went through `objcopy --only-keep-debug`.
481       // In this case we don't want to cause the parsing of the object file to
482       // fail, otherwise it will be impossible to use this object as debug info
483       // in LLDB. Return SectionStrippedError here so that
484       // COFFObjectFile::initialize can ignore the error.
485       // Somewhat common binaries may have RVAs pointing outside of the
486       // provided raw data. Instead of rejecting the binaries, just
487       // treat the section as stripped for these purposes.
488       if (Section->SizeOfRawData < Section->VirtualSize &&
489           Addr >= SectionStart + Section->SizeOfRawData) {
490         return make_error<SectionStrippedError>();
491       }
492       uint32_t Offset = Addr - SectionStart;
493       Res = reinterpret_cast<uintptr_t>(base()) + Section->PointerToRawData +
494             Offset;
495       return Error::success();
496     }
497   }
498   if (ErrorContext)
499     return createStringError(object_error::parse_failed,
500                              "RVA 0x%" PRIx32 " for %s not found", Addr,
501                              ErrorContext);
502   return createStringError(object_error::parse_failed,
503                            "RVA 0x%" PRIx32 " not found", Addr);
504 }
505 
506 Error COFFObjectFile::getRvaAndSizeAsBytes(uint32_t RVA, uint32_t Size,
507                                            ArrayRef<uint8_t> &Contents,
508                                            const char *ErrorContext) const {
509   for (const SectionRef &S : sections()) {
510     const coff_section *Section = getCOFFSection(S);
511     uint32_t SectionStart = Section->VirtualAddress;
512     // Check if this RVA is within the section bounds. Be careful about integer
513     // overflow.
514     uint32_t OffsetIntoSection = RVA - SectionStart;
515     if (SectionStart <= RVA && OffsetIntoSection < Section->VirtualSize &&
516         Size <= Section->VirtualSize - OffsetIntoSection) {
517       uintptr_t Begin = reinterpret_cast<uintptr_t>(base()) +
518                         Section->PointerToRawData + OffsetIntoSection;
519       Contents =
520           ArrayRef<uint8_t>(reinterpret_cast<const uint8_t *>(Begin), Size);
521       return Error::success();
522     }
523   }
524   if (ErrorContext)
525     return createStringError(object_error::parse_failed,
526                              "RVA 0x%" PRIx32 " for %s not found", RVA,
527                              ErrorContext);
528   return createStringError(object_error::parse_failed,
529                            "RVA 0x%" PRIx32 " not found", RVA);
530 }
531 
532 // Returns hint and name fields, assuming \p Rva is pointing to a Hint/Name
533 // table entry.
534 Error COFFObjectFile::getHintName(uint32_t Rva, uint16_t &Hint,
535                                   StringRef &Name) const {
536   uintptr_t IntPtr = 0;
537   if (Error E = getRvaPtr(Rva, IntPtr))
538     return E;
539   const uint8_t *Ptr = reinterpret_cast<const uint8_t *>(IntPtr);
540   Hint = *reinterpret_cast<const ulittle16_t *>(Ptr);
541   Name = StringRef(reinterpret_cast<const char *>(Ptr + 2));
542   return Error::success();
543 }
544 
545 Error COFFObjectFile::getDebugPDBInfo(const debug_directory *DebugDir,
546                                       const codeview::DebugInfo *&PDBInfo,
547                                       StringRef &PDBFileName) const {
548   ArrayRef<uint8_t> InfoBytes;
549   if (Error E =
550           getRvaAndSizeAsBytes(DebugDir->AddressOfRawData, DebugDir->SizeOfData,
551                                InfoBytes, "PDB info"))
552     return E;
553   if (InfoBytes.size() < sizeof(*PDBInfo) + 1)
554     return createStringError(object_error::parse_failed, "PDB info too small");
555   PDBInfo = reinterpret_cast<const codeview::DebugInfo *>(InfoBytes.data());
556   InfoBytes = InfoBytes.drop_front(sizeof(*PDBInfo));
557   PDBFileName = StringRef(reinterpret_cast<const char *>(InfoBytes.data()),
558                           InfoBytes.size());
559   // Truncate the name at the first null byte. Ignore any padding.
560   PDBFileName = PDBFileName.split('\0').first;
561   return Error::success();
562 }
563 
564 Error COFFObjectFile::getDebugPDBInfo(const codeview::DebugInfo *&PDBInfo,
565                                       StringRef &PDBFileName) const {
566   for (const debug_directory &D : debug_directories())
567     if (D.Type == COFF::IMAGE_DEBUG_TYPE_CODEVIEW)
568       return getDebugPDBInfo(&D, PDBInfo, PDBFileName);
569   // If we get here, there is no PDB info to return.
570   PDBInfo = nullptr;
571   PDBFileName = StringRef();
572   return Error::success();
573 }
574 
575 // Find the import table.
576 Error COFFObjectFile::initImportTablePtr() {
577   // First, we get the RVA of the import table. If the file lacks a pointer to
578   // the import table, do nothing.
579   const data_directory *DataEntry = getDataDirectory(COFF::IMPORT_TABLE);
580   if (!DataEntry)
581     return Error::success();
582 
583   // Do nothing if the pointer to import table is NULL.
584   if (DataEntry->RelativeVirtualAddress == 0)
585     return Error::success();
586 
587   uint32_t ImportTableRva = DataEntry->RelativeVirtualAddress;
588 
589   // Find the section that contains the RVA. This is needed because the RVA is
590   // the import table's memory address which is different from its file offset.
591   uintptr_t IntPtr = 0;
592   if (Error E = getRvaPtr(ImportTableRva, IntPtr, "import table"))
593     return E;
594   if (Error E = checkOffset(Data, IntPtr, DataEntry->Size))
595     return E;
596   ImportDirectory = reinterpret_cast<
597       const coff_import_directory_table_entry *>(IntPtr);
598   return Error::success();
599 }
600 
601 // Initializes DelayImportDirectory and NumberOfDelayImportDirectory.
602 Error COFFObjectFile::initDelayImportTablePtr() {
603   const data_directory *DataEntry =
604       getDataDirectory(COFF::DELAY_IMPORT_DESCRIPTOR);
605   if (!DataEntry)
606     return Error::success();
607   if (DataEntry->RelativeVirtualAddress == 0)
608     return Error::success();
609 
610   uint32_t RVA = DataEntry->RelativeVirtualAddress;
611   NumberOfDelayImportDirectory = DataEntry->Size /
612       sizeof(delay_import_directory_table_entry) - 1;
613 
614   uintptr_t IntPtr = 0;
615   if (Error E = getRvaPtr(RVA, IntPtr, "delay import table"))
616     return E;
617   if (Error E = checkOffset(Data, IntPtr, DataEntry->Size))
618     return E;
619 
620   DelayImportDirectory = reinterpret_cast<
621       const delay_import_directory_table_entry *>(IntPtr);
622   return Error::success();
623 }
624 
625 // Find the export table.
626 Error COFFObjectFile::initExportTablePtr() {
627   // First, we get the RVA of the export table. If the file lacks a pointer to
628   // the export table, do nothing.
629   const data_directory *DataEntry = getDataDirectory(COFF::EXPORT_TABLE);
630   if (!DataEntry)
631     return Error::success();
632 
633   // Do nothing if the pointer to export table is NULL.
634   if (DataEntry->RelativeVirtualAddress == 0)
635     return Error::success();
636 
637   uint32_t ExportTableRva = DataEntry->RelativeVirtualAddress;
638   uintptr_t IntPtr = 0;
639   if (Error E = getRvaPtr(ExportTableRva, IntPtr, "export table"))
640     return E;
641   if (Error E = checkOffset(Data, IntPtr, DataEntry->Size))
642     return E;
643 
644   ExportDirectory =
645       reinterpret_cast<const export_directory_table_entry *>(IntPtr);
646   return Error::success();
647 }
648 
649 Error COFFObjectFile::initBaseRelocPtr() {
650   const data_directory *DataEntry =
651       getDataDirectory(COFF::BASE_RELOCATION_TABLE);
652   if (!DataEntry)
653     return Error::success();
654   if (DataEntry->RelativeVirtualAddress == 0)
655     return Error::success();
656 
657   uintptr_t IntPtr = 0;
658   if (Error E = getRvaPtr(DataEntry->RelativeVirtualAddress, IntPtr,
659                           "base reloc table"))
660     return E;
661   if (Error E = checkOffset(Data, IntPtr, DataEntry->Size))
662     return E;
663 
664   BaseRelocHeader = reinterpret_cast<const coff_base_reloc_block_header *>(
665       IntPtr);
666   BaseRelocEnd = reinterpret_cast<coff_base_reloc_block_header *>(
667       IntPtr + DataEntry->Size);
668   // FIXME: Verify the section containing BaseRelocHeader has at least
669   // DataEntry->Size bytes after DataEntry->RelativeVirtualAddress.
670   return Error::success();
671 }
672 
673 Error COFFObjectFile::initDebugDirectoryPtr() {
674   // Get the RVA of the debug directory. Do nothing if it does not exist.
675   const data_directory *DataEntry = getDataDirectory(COFF::DEBUG_DIRECTORY);
676   if (!DataEntry)
677     return Error::success();
678 
679   // Do nothing if the RVA is NULL.
680   if (DataEntry->RelativeVirtualAddress == 0)
681     return Error::success();
682 
683   // Check that the size is a multiple of the entry size.
684   if (DataEntry->Size % sizeof(debug_directory) != 0)
685     return createStringError(object_error::parse_failed,
686                              "debug directory has uneven size");
687 
688   uintptr_t IntPtr = 0;
689   if (Error E = getRvaPtr(DataEntry->RelativeVirtualAddress, IntPtr,
690                           "debug directory"))
691     return E;
692   if (Error E = checkOffset(Data, IntPtr, DataEntry->Size))
693     return E;
694 
695   DebugDirectoryBegin = reinterpret_cast<const debug_directory *>(IntPtr);
696   DebugDirectoryEnd = reinterpret_cast<const debug_directory *>(
697       IntPtr + DataEntry->Size);
698   // FIXME: Verify the section containing DebugDirectoryBegin has at least
699   // DataEntry->Size bytes after DataEntry->RelativeVirtualAddress.
700   return Error::success();
701 }
702 
703 Error COFFObjectFile::initTLSDirectoryPtr() {
704   // Get the RVA of the TLS directory. Do nothing if it does not exist.
705   const data_directory *DataEntry = getDataDirectory(COFF::TLS_TABLE);
706   if (!DataEntry)
707     return Error::success();
708 
709   // Do nothing if the RVA is NULL.
710   if (DataEntry->RelativeVirtualAddress == 0)
711     return Error::success();
712 
713   uint64_t DirSize =
714       is64() ? sizeof(coff_tls_directory64) : sizeof(coff_tls_directory32);
715 
716   // Check that the size is correct.
717   if (DataEntry->Size != DirSize)
718     return createStringError(
719         object_error::parse_failed,
720         "TLS Directory size (%u) is not the expected size (%" PRIu64 ").",
721         static_cast<uint32_t>(DataEntry->Size), DirSize);
722 
723   uintptr_t IntPtr = 0;
724   if (Error E =
725           getRvaPtr(DataEntry->RelativeVirtualAddress, IntPtr, "TLS directory"))
726     return E;
727   if (Error E = checkOffset(Data, IntPtr, DataEntry->Size))
728     return E;
729 
730   if (is64())
731     TLSDirectory64 = reinterpret_cast<const coff_tls_directory64 *>(IntPtr);
732   else
733     TLSDirectory32 = reinterpret_cast<const coff_tls_directory32 *>(IntPtr);
734 
735   return Error::success();
736 }
737 
738 Error COFFObjectFile::initLoadConfigPtr() {
739   // Get the RVA of the debug directory. Do nothing if it does not exist.
740   const data_directory *DataEntry = getDataDirectory(COFF::LOAD_CONFIG_TABLE);
741   if (!DataEntry)
742     return Error::success();
743 
744   // Do nothing if the RVA is NULL.
745   if (DataEntry->RelativeVirtualAddress == 0)
746     return Error::success();
747   uintptr_t IntPtr = 0;
748   if (Error E = getRvaPtr(DataEntry->RelativeVirtualAddress, IntPtr,
749                           "load config table"))
750     return E;
751   if (Error E = checkOffset(Data, IntPtr, DataEntry->Size))
752     return E;
753 
754   LoadConfig = (const void *)IntPtr;
755 
756   if (is64()) {
757     auto Config = getLoadConfig64();
758     if (Config->Size >=
759             offsetof(coff_load_configuration64, CHPEMetadataPointer) +
760                 sizeof(Config->CHPEMetadataPointer) &&
761         Config->CHPEMetadataPointer) {
762       uint64_t ChpeOff = Config->CHPEMetadataPointer;
763       if (Error E =
764               getRvaPtr(ChpeOff - getImageBase(), IntPtr, "CHPE metadata"))
765         return E;
766       if (Error E = checkOffset(Data, IntPtr, sizeof(*CHPEMetadata)))
767         return E;
768 
769       CHPEMetadata = reinterpret_cast<const chpe_metadata *>(IntPtr);
770 
771       // Validate CHPE metadata
772       if (CHPEMetadata->CodeMapCount) {
773         if (Error E = getRvaPtr(CHPEMetadata->CodeMap, IntPtr, "CHPE code map"))
774           return E;
775         if (Error E = checkOffset(Data, IntPtr,
776                                   CHPEMetadata->CodeMapCount *
777                                       sizeof(chpe_range_entry)))
778           return E;
779       }
780 
781       if (CHPEMetadata->CodeRangesToEntryPointsCount) {
782         if (Error E = getRvaPtr(CHPEMetadata->CodeRangesToEntryPoints, IntPtr,
783                                 "CHPE entry point ranges"))
784           return E;
785         if (Error E = checkOffset(Data, IntPtr,
786                                   CHPEMetadata->CodeRangesToEntryPointsCount *
787                                       sizeof(chpe_code_range_entry)))
788           return E;
789       }
790 
791       if (CHPEMetadata->RedirectionMetadataCount) {
792         if (Error E = getRvaPtr(CHPEMetadata->RedirectionMetadata, IntPtr,
793                                 "CHPE redirection metadata"))
794           return E;
795         if (Error E = checkOffset(Data, IntPtr,
796                                   CHPEMetadata->RedirectionMetadataCount *
797                                       sizeof(chpe_redirection_entry)))
798           return E;
799       }
800     }
801 
802     if (Config->Size >=
803         offsetof(coff_load_configuration64, DynamicValueRelocTableSection) +
804             sizeof(Config->DynamicValueRelocTableSection))
805       if (Error E = initDynamicRelocPtr(Config->DynamicValueRelocTableSection,
806                                         Config->DynamicValueRelocTableOffset))
807         return E;
808   } else {
809     auto Config = getLoadConfig32();
810     if (Config->Size >=
811         offsetof(coff_load_configuration32, DynamicValueRelocTableSection) +
812             sizeof(Config->DynamicValueRelocTableSection)) {
813       if (Error E = initDynamicRelocPtr(Config->DynamicValueRelocTableSection,
814                                         Config->DynamicValueRelocTableOffset))
815         return E;
816     }
817   }
818   return Error::success();
819 }
820 
821 Error COFFObjectFile::initDynamicRelocPtr(uint32_t SectionIndex,
822                                           uint32_t SectionOffset) {
823   Expected<const coff_section *> Section = getSection(SectionIndex);
824   if (!Section)
825     return Section.takeError();
826   if (!*Section)
827     return Error::success();
828 
829   // Interpret and validate dynamic relocations.
830   ArrayRef<uint8_t> Contents;
831   if (Error E = getSectionContents(*Section, Contents))
832     return E;
833 
834   Contents = Contents.drop_front(SectionOffset);
835   if (Contents.size() < sizeof(coff_dynamic_reloc_table))
836     return createStringError(object_error::parse_failed,
837                              "Too large DynamicValueRelocTableOffset (" +
838                                  Twine(SectionOffset) + ")");
839 
840   DynamicRelocTable =
841       reinterpret_cast<const coff_dynamic_reloc_table *>(Contents.data());
842 
843   if (DynamicRelocTable->Version != 1 && DynamicRelocTable->Version != 2)
844     return createStringError(object_error::parse_failed,
845                              "Unsupported dynamic relocations table version (" +
846                                  Twine(DynamicRelocTable->Version) + ")");
847   if (DynamicRelocTable->Size > Contents.size() - sizeof(*DynamicRelocTable))
848     return createStringError(object_error::parse_failed,
849                              "Indvalid dynamic relocations directory size (" +
850                                  Twine(DynamicRelocTable->Size) + ")");
851 
852   for (auto DynReloc : dynamic_relocs()) {
853     if (Error e = DynReloc.validate())
854       return e;
855   }
856 
857   return Error::success();
858 }
859 
860 Expected<std::unique_ptr<COFFObjectFile>>
861 COFFObjectFile::create(MemoryBufferRef Object) {
862   std::unique_ptr<COFFObjectFile> Obj(new COFFObjectFile(std::move(Object)));
863   if (Error E = Obj->initialize())
864     return E;
865   return std::move(Obj);
866 }
867 
868 COFFObjectFile::COFFObjectFile(MemoryBufferRef Object)
869     : ObjectFile(Binary::ID_COFF, Object), COFFHeader(nullptr),
870       COFFBigObjHeader(nullptr), PE32Header(nullptr), PE32PlusHeader(nullptr),
871       DataDirectory(nullptr), SectionTable(nullptr), SymbolTable16(nullptr),
872       SymbolTable32(nullptr), StringTable(nullptr), StringTableSize(0),
873       ImportDirectory(nullptr), DelayImportDirectory(nullptr),
874       NumberOfDelayImportDirectory(0), ExportDirectory(nullptr),
875       BaseRelocHeader(nullptr), BaseRelocEnd(nullptr),
876       DebugDirectoryBegin(nullptr), DebugDirectoryEnd(nullptr),
877       TLSDirectory32(nullptr), TLSDirectory64(nullptr) {}
878 
879 static Error ignoreStrippedErrors(Error E) {
880   if (E.isA<SectionStrippedError>()) {
881     consumeError(std::move(E));
882     return Error::success();
883   }
884   return E;
885 }
886 
887 Error COFFObjectFile::initialize() {
888   // Check that we at least have enough room for a header.
889   std::error_code EC;
890   if (!checkSize(Data, EC, sizeof(coff_file_header)))
891     return errorCodeToError(EC);
892 
893   // The current location in the file where we are looking at.
894   uint64_t CurPtr = 0;
895 
896   // PE header is optional and is present only in executables. If it exists,
897   // it is placed right after COFF header.
898   bool HasPEHeader = false;
899 
900   // Check if this is a PE/COFF file.
901   if (checkSize(Data, EC, sizeof(dos_header) + sizeof(COFF::PEMagic))) {
902     // PE/COFF, seek through MS-DOS compatibility stub and 4-byte
903     // PE signature to find 'normal' COFF header.
904     const auto *DH = reinterpret_cast<const dos_header *>(base());
905     if (DH->Magic[0] == 'M' && DH->Magic[1] == 'Z') {
906       CurPtr = DH->AddressOfNewExeHeader;
907       // Check the PE magic bytes. ("PE\0\0")
908       if (memcmp(base() + CurPtr, COFF::PEMagic, sizeof(COFF::PEMagic)) != 0) {
909         return createStringError(object_error::parse_failed,
910                                  "incorrect PE magic");
911       }
912       CurPtr += sizeof(COFF::PEMagic); // Skip the PE magic bytes.
913       HasPEHeader = true;
914     }
915   }
916 
917   if (Error E = getObject(COFFHeader, Data, base() + CurPtr))
918     return E;
919 
920   // It might be a bigobj file, let's check.  Note that COFF bigobj and COFF
921   // import libraries share a common prefix but bigobj is more restrictive.
922   if (!HasPEHeader && COFFHeader->Machine == COFF::IMAGE_FILE_MACHINE_UNKNOWN &&
923       COFFHeader->NumberOfSections == uint16_t(0xffff) &&
924       checkSize(Data, EC, sizeof(coff_bigobj_file_header))) {
925     if (Error E = getObject(COFFBigObjHeader, Data, base() + CurPtr))
926       return E;
927 
928     // Verify that we are dealing with bigobj.
929     if (COFFBigObjHeader->Version >= COFF::BigObjHeader::MinBigObjectVersion &&
930         std::memcmp(COFFBigObjHeader->UUID, COFF::BigObjMagic,
931                     sizeof(COFF::BigObjMagic)) == 0) {
932       COFFHeader = nullptr;
933       CurPtr += sizeof(coff_bigobj_file_header);
934     } else {
935       // It's not a bigobj.
936       COFFBigObjHeader = nullptr;
937     }
938   }
939   if (COFFHeader) {
940     // The prior checkSize call may have failed.  This isn't a hard error
941     // because we were just trying to sniff out bigobj.
942     EC = std::error_code();
943     CurPtr += sizeof(coff_file_header);
944 
945     if (COFFHeader->isImportLibrary())
946       return errorCodeToError(EC);
947   }
948 
949   if (HasPEHeader) {
950     const pe32_header *Header;
951     if (Error E = getObject(Header, Data, base() + CurPtr))
952       return E;
953 
954     const uint8_t *DataDirAddr;
955     uint64_t DataDirSize;
956     if (Header->Magic == COFF::PE32Header::PE32) {
957       PE32Header = Header;
958       DataDirAddr = base() + CurPtr + sizeof(pe32_header);
959       DataDirSize = sizeof(data_directory) * PE32Header->NumberOfRvaAndSize;
960     } else if (Header->Magic == COFF::PE32Header::PE32_PLUS) {
961       PE32PlusHeader = reinterpret_cast<const pe32plus_header *>(Header);
962       DataDirAddr = base() + CurPtr + sizeof(pe32plus_header);
963       DataDirSize = sizeof(data_directory) * PE32PlusHeader->NumberOfRvaAndSize;
964     } else {
965       // It's neither PE32 nor PE32+.
966       return createStringError(object_error::parse_failed,
967                                "incorrect PE magic");
968     }
969     if (Error E = getObject(DataDirectory, Data, DataDirAddr, DataDirSize))
970       return E;
971   }
972 
973   if (COFFHeader)
974     CurPtr += COFFHeader->SizeOfOptionalHeader;
975 
976   assert(COFFHeader || COFFBigObjHeader);
977 
978   if (Error E =
979           getObject(SectionTable, Data, base() + CurPtr,
980                     (uint64_t)getNumberOfSections() * sizeof(coff_section)))
981     return E;
982 
983   // Initialize the pointer to the symbol table.
984   if (getPointerToSymbolTable() != 0) {
985     if (Error E = initSymbolTablePtr()) {
986       // Recover from errors reading the symbol table.
987       consumeError(std::move(E));
988       SymbolTable16 = nullptr;
989       SymbolTable32 = nullptr;
990       StringTable = nullptr;
991       StringTableSize = 0;
992     }
993   } else {
994     // We had better not have any symbols if we don't have a symbol table.
995     if (getNumberOfSymbols() != 0) {
996       return createStringError(object_error::parse_failed,
997                                "symbol table missing");
998     }
999   }
1000 
1001   // Initialize the pointer to the beginning of the import table.
1002   if (Error E = ignoreStrippedErrors(initImportTablePtr()))
1003     return E;
1004   if (Error E = ignoreStrippedErrors(initDelayImportTablePtr()))
1005     return E;
1006 
1007   // Initialize the pointer to the export table.
1008   if (Error E = ignoreStrippedErrors(initExportTablePtr()))
1009     return E;
1010 
1011   // Initialize the pointer to the base relocation table.
1012   if (Error E = ignoreStrippedErrors(initBaseRelocPtr()))
1013     return E;
1014 
1015   // Initialize the pointer to the debug directory.
1016   if (Error E = ignoreStrippedErrors(initDebugDirectoryPtr()))
1017     return E;
1018 
1019   // Initialize the pointer to the TLS directory.
1020   if (Error E = ignoreStrippedErrors(initTLSDirectoryPtr()))
1021     return E;
1022 
1023   if (Error E = ignoreStrippedErrors(initLoadConfigPtr()))
1024     return E;
1025 
1026   return Error::success();
1027 }
1028 
1029 basic_symbol_iterator COFFObjectFile::symbol_begin() const {
1030   DataRefImpl Ret;
1031   Ret.p = getSymbolTable();
1032   return basic_symbol_iterator(SymbolRef(Ret, this));
1033 }
1034 
1035 basic_symbol_iterator COFFObjectFile::symbol_end() const {
1036   // The symbol table ends where the string table begins.
1037   DataRefImpl Ret;
1038   Ret.p = reinterpret_cast<uintptr_t>(StringTable);
1039   return basic_symbol_iterator(SymbolRef(Ret, this));
1040 }
1041 
1042 import_directory_iterator COFFObjectFile::import_directory_begin() const {
1043   if (!ImportDirectory)
1044     return import_directory_end();
1045   if (ImportDirectory->isNull())
1046     return import_directory_end();
1047   return import_directory_iterator(
1048       ImportDirectoryEntryRef(ImportDirectory, 0, this));
1049 }
1050 
1051 import_directory_iterator COFFObjectFile::import_directory_end() const {
1052   return import_directory_iterator(
1053       ImportDirectoryEntryRef(nullptr, -1, this));
1054 }
1055 
1056 delay_import_directory_iterator
1057 COFFObjectFile::delay_import_directory_begin() const {
1058   return delay_import_directory_iterator(
1059       DelayImportDirectoryEntryRef(DelayImportDirectory, 0, this));
1060 }
1061 
1062 delay_import_directory_iterator
1063 COFFObjectFile::delay_import_directory_end() const {
1064   return delay_import_directory_iterator(
1065       DelayImportDirectoryEntryRef(
1066           DelayImportDirectory, NumberOfDelayImportDirectory, this));
1067 }
1068 
1069 export_directory_iterator COFFObjectFile::export_directory_begin() const {
1070   return export_directory_iterator(
1071       ExportDirectoryEntryRef(ExportDirectory, 0, this));
1072 }
1073 
1074 export_directory_iterator COFFObjectFile::export_directory_end() const {
1075   if (!ExportDirectory)
1076     return export_directory_iterator(ExportDirectoryEntryRef(nullptr, 0, this));
1077   ExportDirectoryEntryRef Ref(ExportDirectory,
1078                               ExportDirectory->AddressTableEntries, this);
1079   return export_directory_iterator(Ref);
1080 }
1081 
1082 section_iterator COFFObjectFile::section_begin() const {
1083   DataRefImpl Ret;
1084   Ret.p = reinterpret_cast<uintptr_t>(SectionTable);
1085   return section_iterator(SectionRef(Ret, this));
1086 }
1087 
1088 section_iterator COFFObjectFile::section_end() const {
1089   DataRefImpl Ret;
1090   int NumSections =
1091       COFFHeader && COFFHeader->isImportLibrary() ? 0 : getNumberOfSections();
1092   Ret.p = reinterpret_cast<uintptr_t>(SectionTable + NumSections);
1093   return section_iterator(SectionRef(Ret, this));
1094 }
1095 
1096 base_reloc_iterator COFFObjectFile::base_reloc_begin() const {
1097   return base_reloc_iterator(BaseRelocRef(BaseRelocHeader, this));
1098 }
1099 
1100 base_reloc_iterator COFFObjectFile::base_reloc_end() const {
1101   return base_reloc_iterator(BaseRelocRef(BaseRelocEnd, this));
1102 }
1103 
1104 dynamic_reloc_iterator COFFObjectFile::dynamic_reloc_begin() const {
1105   const void *Header = DynamicRelocTable ? DynamicRelocTable + 1 : nullptr;
1106   return dynamic_reloc_iterator(DynamicRelocRef(Header, this));
1107 }
1108 
1109 dynamic_reloc_iterator COFFObjectFile::dynamic_reloc_end() const {
1110   const void *Header = nullptr;
1111   if (DynamicRelocTable)
1112     Header = reinterpret_cast<const uint8_t *>(DynamicRelocTable + 1) +
1113              DynamicRelocTable->Size;
1114   return dynamic_reloc_iterator(DynamicRelocRef(Header, this));
1115 }
1116 
1117 uint8_t COFFObjectFile::getBytesInAddress() const {
1118   return getArch() == Triple::x86_64 || getArch() == Triple::aarch64 ? 8 : 4;
1119 }
1120 
1121 StringRef COFFObjectFile::getFileFormatName() const {
1122   switch(getMachine()) {
1123   case COFF::IMAGE_FILE_MACHINE_I386:
1124     return "COFF-i386";
1125   case COFF::IMAGE_FILE_MACHINE_AMD64:
1126     return "COFF-x86-64";
1127   case COFF::IMAGE_FILE_MACHINE_ARMNT:
1128     return "COFF-ARM";
1129   case COFF::IMAGE_FILE_MACHINE_ARM64:
1130     return "COFF-ARM64";
1131   case COFF::IMAGE_FILE_MACHINE_ARM64EC:
1132     return "COFF-ARM64EC";
1133   case COFF::IMAGE_FILE_MACHINE_ARM64X:
1134     return "COFF-ARM64X";
1135   case COFF::IMAGE_FILE_MACHINE_R4000:
1136     return "COFF-MIPS";
1137   default:
1138     return "COFF-<unknown arch>";
1139   }
1140 }
1141 
1142 Triple::ArchType COFFObjectFile::getArch() const {
1143   return getMachineArchType(getMachine());
1144 }
1145 
1146 Expected<uint64_t> COFFObjectFile::getStartAddress() const {
1147   if (PE32Header)
1148     return PE32Header->AddressOfEntryPoint;
1149   return 0;
1150 }
1151 
1152 iterator_range<import_directory_iterator>
1153 COFFObjectFile::import_directories() const {
1154   return make_range(import_directory_begin(), import_directory_end());
1155 }
1156 
1157 iterator_range<delay_import_directory_iterator>
1158 COFFObjectFile::delay_import_directories() const {
1159   return make_range(delay_import_directory_begin(),
1160                     delay_import_directory_end());
1161 }
1162 
1163 iterator_range<export_directory_iterator>
1164 COFFObjectFile::export_directories() const {
1165   return make_range(export_directory_begin(), export_directory_end());
1166 }
1167 
1168 iterator_range<base_reloc_iterator> COFFObjectFile::base_relocs() const {
1169   return make_range(base_reloc_begin(), base_reloc_end());
1170 }
1171 
1172 iterator_range<dynamic_reloc_iterator> COFFObjectFile::dynamic_relocs() const {
1173   return make_range(dynamic_reloc_begin(), dynamic_reloc_end());
1174 }
1175 
1176 const data_directory *COFFObjectFile::getDataDirectory(uint32_t Index) const {
1177   if (!DataDirectory)
1178     return nullptr;
1179   assert(PE32Header || PE32PlusHeader);
1180   uint32_t NumEnt = PE32Header ? PE32Header->NumberOfRvaAndSize
1181                                : PE32PlusHeader->NumberOfRvaAndSize;
1182   if (Index >= NumEnt)
1183     return nullptr;
1184   return &DataDirectory[Index];
1185 }
1186 
1187 Expected<const coff_section *> COFFObjectFile::getSection(int32_t Index) const {
1188   // Perhaps getting the section of a reserved section index should be an error,
1189   // but callers rely on this to return null.
1190   if (COFF::isReservedSectionNumber(Index))
1191     return (const coff_section *)nullptr;
1192   if (static_cast<uint32_t>(Index) <= getNumberOfSections()) {
1193     // We already verified the section table data, so no need to check again.
1194     return SectionTable + (Index - 1);
1195   }
1196   return createStringError(object_error::parse_failed,
1197                            "section index out of bounds");
1198 }
1199 
1200 Expected<StringRef> COFFObjectFile::getString(uint32_t Offset) const {
1201   if (StringTableSize <= 4)
1202     // Tried to get a string from an empty string table.
1203     return createStringError(object_error::parse_failed, "string table empty");
1204   if (Offset >= StringTableSize)
1205     return errorCodeToError(object_error::unexpected_eof);
1206   return StringRef(StringTable + Offset);
1207 }
1208 
1209 Expected<StringRef> COFFObjectFile::getSymbolName(COFFSymbolRef Symbol) const {
1210   return getSymbolName(Symbol.getGeneric());
1211 }
1212 
1213 Expected<StringRef>
1214 COFFObjectFile::getSymbolName(const coff_symbol_generic *Symbol) const {
1215   // Check for string table entry. First 4 bytes are 0.
1216   if (Symbol->Name.Offset.Zeroes == 0)
1217     return getString(Symbol->Name.Offset.Offset);
1218 
1219   // Null terminated, let ::strlen figure out the length.
1220   if (Symbol->Name.ShortName[COFF::NameSize - 1] == 0)
1221     return StringRef(Symbol->Name.ShortName);
1222 
1223   // Not null terminated, use all 8 bytes.
1224   return StringRef(Symbol->Name.ShortName, COFF::NameSize);
1225 }
1226 
1227 ArrayRef<uint8_t>
1228 COFFObjectFile::getSymbolAuxData(COFFSymbolRef Symbol) const {
1229   const uint8_t *Aux = nullptr;
1230 
1231   size_t SymbolSize = getSymbolTableEntrySize();
1232   if (Symbol.getNumberOfAuxSymbols() > 0) {
1233     // AUX data comes immediately after the symbol in COFF
1234     Aux = reinterpret_cast<const uint8_t *>(Symbol.getRawPtr()) + SymbolSize;
1235 #ifndef NDEBUG
1236     // Verify that the Aux symbol points to a valid entry in the symbol table.
1237     uintptr_t Offset = uintptr_t(Aux) - uintptr_t(base());
1238     if (Offset < getPointerToSymbolTable() ||
1239         Offset >=
1240             getPointerToSymbolTable() + (getNumberOfSymbols() * SymbolSize))
1241       report_fatal_error("Aux Symbol data was outside of symbol table.");
1242 
1243     assert((Offset - getPointerToSymbolTable()) % SymbolSize == 0 &&
1244            "Aux Symbol data did not point to the beginning of a symbol");
1245 #endif
1246   }
1247   return ArrayRef(Aux, Symbol.getNumberOfAuxSymbols() * SymbolSize);
1248 }
1249 
1250 uint32_t COFFObjectFile::getSymbolIndex(COFFSymbolRef Symbol) const {
1251   uintptr_t Offset =
1252       reinterpret_cast<uintptr_t>(Symbol.getRawPtr()) - getSymbolTable();
1253   assert(Offset % getSymbolTableEntrySize() == 0 &&
1254          "Symbol did not point to the beginning of a symbol");
1255   size_t Index = Offset / getSymbolTableEntrySize();
1256   assert(Index < getNumberOfSymbols());
1257   return Index;
1258 }
1259 
1260 Expected<StringRef>
1261 COFFObjectFile::getSectionName(const coff_section *Sec) const {
1262   StringRef Name = StringRef(Sec->Name, COFF::NameSize).split('\0').first;
1263 
1264   // Check for string table entry. First byte is '/'.
1265   if (Name.starts_with("/")) {
1266     uint32_t Offset;
1267     if (Name.starts_with("//")) {
1268       if (decodeBase64StringEntry(Name.substr(2), Offset))
1269         return createStringError(object_error::parse_failed,
1270                                  "invalid section name");
1271     } else {
1272       if (Name.substr(1).getAsInteger(10, Offset))
1273         return createStringError(object_error::parse_failed,
1274                                  "invalid section name");
1275     }
1276     return getString(Offset);
1277   }
1278 
1279   return Name;
1280 }
1281 
1282 uint64_t COFFObjectFile::getSectionSize(const coff_section *Sec) const {
1283   // SizeOfRawData and VirtualSize change what they represent depending on
1284   // whether or not we have an executable image.
1285   //
1286   // For object files, SizeOfRawData contains the size of section's data;
1287   // VirtualSize should be zero but isn't due to buggy COFF writers.
1288   //
1289   // For executables, SizeOfRawData *must* be a multiple of FileAlignment; the
1290   // actual section size is in VirtualSize.  It is possible for VirtualSize to
1291   // be greater than SizeOfRawData; the contents past that point should be
1292   // considered to be zero.
1293   if (getDOSHeader())
1294     return std::min(Sec->VirtualSize, Sec->SizeOfRawData);
1295   return Sec->SizeOfRawData;
1296 }
1297 
1298 Error COFFObjectFile::getSectionContents(const coff_section *Sec,
1299                                          ArrayRef<uint8_t> &Res) const {
1300   // In COFF, a virtual section won't have any in-file
1301   // content, so the file pointer to the content will be zero.
1302   if (Sec->PointerToRawData == 0)
1303     return Error::success();
1304   // The only thing that we need to verify is that the contents is contained
1305   // within the file bounds. We don't need to make sure it doesn't cover other
1306   // data, as there's nothing that says that is not allowed.
1307   uintptr_t ConStart =
1308       reinterpret_cast<uintptr_t>(base()) + Sec->PointerToRawData;
1309   uint32_t SectionSize = getSectionSize(Sec);
1310   if (Error E = checkOffset(Data, ConStart, SectionSize))
1311     return E;
1312   Res = ArrayRef(reinterpret_cast<const uint8_t *>(ConStart), SectionSize);
1313   return Error::success();
1314 }
1315 
1316 const coff_relocation *COFFObjectFile::toRel(DataRefImpl Rel) const {
1317   return reinterpret_cast<const coff_relocation*>(Rel.p);
1318 }
1319 
1320 void COFFObjectFile::moveRelocationNext(DataRefImpl &Rel) const {
1321   Rel.p = reinterpret_cast<uintptr_t>(
1322             reinterpret_cast<const coff_relocation*>(Rel.p) + 1);
1323 }
1324 
1325 uint64_t COFFObjectFile::getRelocationOffset(DataRefImpl Rel) const {
1326   const coff_relocation *R = toRel(Rel);
1327   return R->VirtualAddress;
1328 }
1329 
1330 symbol_iterator COFFObjectFile::getRelocationSymbol(DataRefImpl Rel) const {
1331   const coff_relocation *R = toRel(Rel);
1332   DataRefImpl Ref;
1333   if (R->SymbolTableIndex >= getNumberOfSymbols())
1334     return symbol_end();
1335   if (SymbolTable16)
1336     Ref.p = reinterpret_cast<uintptr_t>(SymbolTable16 + R->SymbolTableIndex);
1337   else if (SymbolTable32)
1338     Ref.p = reinterpret_cast<uintptr_t>(SymbolTable32 + R->SymbolTableIndex);
1339   else
1340     llvm_unreachable("no symbol table pointer!");
1341   return symbol_iterator(SymbolRef(Ref, this));
1342 }
1343 
1344 uint64_t COFFObjectFile::getRelocationType(DataRefImpl Rel) const {
1345   const coff_relocation* R = toRel(Rel);
1346   return R->Type;
1347 }
1348 
1349 const coff_section *
1350 COFFObjectFile::getCOFFSection(const SectionRef &Section) const {
1351   return toSec(Section.getRawDataRefImpl());
1352 }
1353 
1354 COFFSymbolRef COFFObjectFile::getCOFFSymbol(const DataRefImpl &Ref) const {
1355   if (SymbolTable16)
1356     return toSymb<coff_symbol16>(Ref);
1357   if (SymbolTable32)
1358     return toSymb<coff_symbol32>(Ref);
1359   llvm_unreachable("no symbol table pointer!");
1360 }
1361 
1362 COFFSymbolRef COFFObjectFile::getCOFFSymbol(const SymbolRef &Symbol) const {
1363   return getCOFFSymbol(Symbol.getRawDataRefImpl());
1364 }
1365 
1366 const coff_relocation *
1367 COFFObjectFile::getCOFFRelocation(const RelocationRef &Reloc) const {
1368   return toRel(Reloc.getRawDataRefImpl());
1369 }
1370 
1371 ArrayRef<coff_relocation>
1372 COFFObjectFile::getRelocations(const coff_section *Sec) const {
1373   return {getFirstReloc(Sec, Data, base()),
1374           getNumberOfRelocations(Sec, Data, base())};
1375 }
1376 
1377 #define LLVM_COFF_SWITCH_RELOC_TYPE_NAME(reloc_type)                           \
1378   case COFF::reloc_type:                                                       \
1379     return #reloc_type;
1380 
1381 StringRef COFFObjectFile::getRelocationTypeName(uint16_t Type) const {
1382   switch (getArch()) {
1383   case Triple::x86_64:
1384     switch (Type) {
1385     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_AMD64_ABSOLUTE);
1386     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_AMD64_ADDR64);
1387     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_AMD64_ADDR32);
1388     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_AMD64_ADDR32NB);
1389     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_AMD64_REL32);
1390     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_AMD64_REL32_1);
1391     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_AMD64_REL32_2);
1392     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_AMD64_REL32_3);
1393     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_AMD64_REL32_4);
1394     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_AMD64_REL32_5);
1395     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_AMD64_SECTION);
1396     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_AMD64_SECREL);
1397     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_AMD64_SECREL7);
1398     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_AMD64_TOKEN);
1399     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_AMD64_SREL32);
1400     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_AMD64_PAIR);
1401     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_AMD64_SSPAN32);
1402     default:
1403       return "Unknown";
1404     }
1405     break;
1406   case Triple::thumb:
1407     switch (Type) {
1408     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_ARM_ABSOLUTE);
1409     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_ARM_ADDR32);
1410     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_ARM_ADDR32NB);
1411     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_ARM_BRANCH24);
1412     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_ARM_BRANCH11);
1413     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_ARM_TOKEN);
1414     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_ARM_BLX24);
1415     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_ARM_BLX11);
1416     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_ARM_REL32);
1417     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_ARM_SECTION);
1418     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_ARM_SECREL);
1419     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_ARM_MOV32A);
1420     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_ARM_MOV32T);
1421     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_ARM_BRANCH20T);
1422     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_ARM_BRANCH24T);
1423     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_ARM_BLX23T);
1424     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_ARM_PAIR);
1425     default:
1426       return "Unknown";
1427     }
1428     break;
1429   case Triple::aarch64:
1430     switch (Type) {
1431     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_ARM64_ABSOLUTE);
1432     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_ARM64_ADDR32);
1433     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_ARM64_ADDR32NB);
1434     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_ARM64_BRANCH26);
1435     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_ARM64_PAGEBASE_REL21);
1436     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_ARM64_REL21);
1437     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_ARM64_PAGEOFFSET_12A);
1438     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_ARM64_PAGEOFFSET_12L);
1439     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_ARM64_SECREL);
1440     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_ARM64_SECREL_LOW12A);
1441     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_ARM64_SECREL_HIGH12A);
1442     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_ARM64_SECREL_LOW12L);
1443     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_ARM64_TOKEN);
1444     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_ARM64_SECTION);
1445     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_ARM64_ADDR64);
1446     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_ARM64_BRANCH19);
1447     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_ARM64_BRANCH14);
1448     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_ARM64_REL32);
1449     default:
1450       return "Unknown";
1451     }
1452     break;
1453   case Triple::x86:
1454     switch (Type) {
1455     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_I386_ABSOLUTE);
1456     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_I386_DIR16);
1457     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_I386_REL16);
1458     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_I386_DIR32);
1459     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_I386_DIR32NB);
1460     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_I386_SEG12);
1461     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_I386_SECTION);
1462     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_I386_SECREL);
1463     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_I386_TOKEN);
1464     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_I386_SECREL7);
1465     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_I386_REL32);
1466     default:
1467       return "Unknown";
1468     }
1469     break;
1470   case Triple::mipsel:
1471     switch (Type) {
1472       LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_MIPS_ABSOLUTE);
1473       LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_MIPS_REFHALF);
1474       LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_MIPS_REFWORD);
1475       LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_MIPS_JMPADDR);
1476       LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_MIPS_REFHI);
1477       LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_MIPS_REFLO);
1478       LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_MIPS_GPREL);
1479       LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_MIPS_LITERAL);
1480       LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_MIPS_SECTION);
1481       LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_MIPS_SECREL);
1482       LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_MIPS_SECRELLO);
1483       LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_MIPS_SECRELHI);
1484       LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_MIPS_JMPADDR16);
1485       LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_MIPS_REFWORDNB);
1486       LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_MIPS_PAIR);
1487     default:
1488       return "Unknown";
1489     }
1490     break;
1491   default:
1492     return "Unknown";
1493   }
1494 }
1495 
1496 #undef LLVM_COFF_SWITCH_RELOC_TYPE_NAME
1497 
1498 void COFFObjectFile::getRelocationTypeName(
1499     DataRefImpl Rel, SmallVectorImpl<char> &Result) const {
1500   const coff_relocation *Reloc = toRel(Rel);
1501   StringRef Res = getRelocationTypeName(Reloc->Type);
1502   Result.append(Res.begin(), Res.end());
1503 }
1504 
1505 bool COFFObjectFile::isRelocatableObject() const {
1506   return !DataDirectory;
1507 }
1508 
1509 StringRef COFFObjectFile::mapDebugSectionName(StringRef Name) const {
1510   return StringSwitch<StringRef>(Name)
1511       .Case("eh_fram", "eh_frame")
1512       .Default(Name);
1513 }
1514 
1515 std::unique_ptr<MemoryBuffer> COFFObjectFile::getHybridObjectView() const {
1516   if (getMachine() != COFF::IMAGE_FILE_MACHINE_ARM64X)
1517     return nullptr;
1518 
1519   std::unique_ptr<WritableMemoryBuffer> HybridView;
1520 
1521   for (auto DynReloc : dynamic_relocs()) {
1522     if (DynReloc.getType() != COFF::IMAGE_DYNAMIC_RELOCATION_ARM64X)
1523       continue;
1524 
1525     for (auto reloc : DynReloc.arm64x_relocs()) {
1526       if (!HybridView) {
1527         HybridView =
1528             WritableMemoryBuffer::getNewUninitMemBuffer(Data.getBufferSize());
1529         memcpy(HybridView->getBufferStart(), Data.getBufferStart(),
1530                Data.getBufferSize());
1531       }
1532 
1533       uint32_t RVA = reloc.getRVA();
1534       void *Ptr;
1535       uintptr_t IntPtr;
1536       if (RVA & ~0xfff) {
1537         cantFail(getRvaPtr(RVA, IntPtr));
1538         Ptr = HybridView->getBufferStart() + IntPtr -
1539               reinterpret_cast<uintptr_t>(base());
1540       } else {
1541         // PE header relocation.
1542         Ptr = HybridView->getBufferStart() + RVA;
1543       }
1544 
1545       switch (reloc.getType()) {
1546       case COFF::IMAGE_DVRT_ARM64X_FIXUP_TYPE_ZEROFILL:
1547         memset(Ptr, 0, reloc.getSize());
1548         break;
1549       case COFF::IMAGE_DVRT_ARM64X_FIXUP_TYPE_VALUE: {
1550         auto Value = static_cast<ulittle64_t>(reloc.getValue());
1551         memcpy(Ptr, &Value, reloc.getSize());
1552         break;
1553       }
1554       case COFF::IMAGE_DVRT_ARM64X_FIXUP_TYPE_DELTA:
1555         *reinterpret_cast<ulittle32_t *>(Ptr) += reloc.getValue();
1556         break;
1557       }
1558     }
1559   }
1560   return HybridView;
1561 }
1562 
1563 bool ImportDirectoryEntryRef::
1564 operator==(const ImportDirectoryEntryRef &Other) const {
1565   return ImportTable == Other.ImportTable && Index == Other.Index;
1566 }
1567 
1568 void ImportDirectoryEntryRef::moveNext() {
1569   ++Index;
1570   if (ImportTable[Index].isNull()) {
1571     Index = -1;
1572     ImportTable = nullptr;
1573   }
1574 }
1575 
1576 Error ImportDirectoryEntryRef::getImportTableEntry(
1577     const coff_import_directory_table_entry *&Result) const {
1578   return getObject(Result, OwningObject->Data, ImportTable + Index);
1579 }
1580 
1581 static imported_symbol_iterator
1582 makeImportedSymbolIterator(const COFFObjectFile *Object,
1583                            uintptr_t Ptr, int Index) {
1584   if (Object->getBytesInAddress() == 4) {
1585     auto *P = reinterpret_cast<const import_lookup_table_entry32 *>(Ptr);
1586     return imported_symbol_iterator(ImportedSymbolRef(P, Index, Object));
1587   }
1588   auto *P = reinterpret_cast<const import_lookup_table_entry64 *>(Ptr);
1589   return imported_symbol_iterator(ImportedSymbolRef(P, Index, Object));
1590 }
1591 
1592 static imported_symbol_iterator
1593 importedSymbolBegin(uint32_t RVA, const COFFObjectFile *Object) {
1594   uintptr_t IntPtr = 0;
1595   // FIXME: Handle errors.
1596   cantFail(Object->getRvaPtr(RVA, IntPtr));
1597   return makeImportedSymbolIterator(Object, IntPtr, 0);
1598 }
1599 
1600 static imported_symbol_iterator
1601 importedSymbolEnd(uint32_t RVA, const COFFObjectFile *Object) {
1602   uintptr_t IntPtr = 0;
1603   // FIXME: Handle errors.
1604   cantFail(Object->getRvaPtr(RVA, IntPtr));
1605   // Forward the pointer to the last entry which is null.
1606   int Index = 0;
1607   if (Object->getBytesInAddress() == 4) {
1608     auto *Entry = reinterpret_cast<ulittle32_t *>(IntPtr);
1609     while (*Entry++)
1610       ++Index;
1611   } else {
1612     auto *Entry = reinterpret_cast<ulittle64_t *>(IntPtr);
1613     while (*Entry++)
1614       ++Index;
1615   }
1616   return makeImportedSymbolIterator(Object, IntPtr, Index);
1617 }
1618 
1619 imported_symbol_iterator
1620 ImportDirectoryEntryRef::imported_symbol_begin() const {
1621   return importedSymbolBegin(ImportTable[Index].ImportAddressTableRVA,
1622                              OwningObject);
1623 }
1624 
1625 imported_symbol_iterator
1626 ImportDirectoryEntryRef::imported_symbol_end() const {
1627   return importedSymbolEnd(ImportTable[Index].ImportAddressTableRVA,
1628                            OwningObject);
1629 }
1630 
1631 iterator_range<imported_symbol_iterator>
1632 ImportDirectoryEntryRef::imported_symbols() const {
1633   return make_range(imported_symbol_begin(), imported_symbol_end());
1634 }
1635 
1636 imported_symbol_iterator ImportDirectoryEntryRef::lookup_table_begin() const {
1637   return importedSymbolBegin(ImportTable[Index].ImportLookupTableRVA,
1638                              OwningObject);
1639 }
1640 
1641 imported_symbol_iterator ImportDirectoryEntryRef::lookup_table_end() const {
1642   return importedSymbolEnd(ImportTable[Index].ImportLookupTableRVA,
1643                            OwningObject);
1644 }
1645 
1646 iterator_range<imported_symbol_iterator>
1647 ImportDirectoryEntryRef::lookup_table_symbols() const {
1648   return make_range(lookup_table_begin(), lookup_table_end());
1649 }
1650 
1651 Error ImportDirectoryEntryRef::getName(StringRef &Result) const {
1652   uintptr_t IntPtr = 0;
1653   if (Error E = OwningObject->getRvaPtr(ImportTable[Index].NameRVA, IntPtr,
1654                                         "import directory name"))
1655     return E;
1656   Result = StringRef(reinterpret_cast<const char *>(IntPtr));
1657   return Error::success();
1658 }
1659 
1660 Error
1661 ImportDirectoryEntryRef::getImportLookupTableRVA(uint32_t  &Result) const {
1662   Result = ImportTable[Index].ImportLookupTableRVA;
1663   return Error::success();
1664 }
1665 
1666 Error ImportDirectoryEntryRef::getImportAddressTableRVA(
1667     uint32_t &Result) const {
1668   Result = ImportTable[Index].ImportAddressTableRVA;
1669   return Error::success();
1670 }
1671 
1672 bool DelayImportDirectoryEntryRef::
1673 operator==(const DelayImportDirectoryEntryRef &Other) const {
1674   return Table == Other.Table && Index == Other.Index;
1675 }
1676 
1677 void DelayImportDirectoryEntryRef::moveNext() {
1678   ++Index;
1679 }
1680 
1681 imported_symbol_iterator
1682 DelayImportDirectoryEntryRef::imported_symbol_begin() const {
1683   return importedSymbolBegin(Table[Index].DelayImportNameTable,
1684                              OwningObject);
1685 }
1686 
1687 imported_symbol_iterator
1688 DelayImportDirectoryEntryRef::imported_symbol_end() const {
1689   return importedSymbolEnd(Table[Index].DelayImportNameTable,
1690                            OwningObject);
1691 }
1692 
1693 iterator_range<imported_symbol_iterator>
1694 DelayImportDirectoryEntryRef::imported_symbols() const {
1695   return make_range(imported_symbol_begin(), imported_symbol_end());
1696 }
1697 
1698 Error DelayImportDirectoryEntryRef::getName(StringRef &Result) const {
1699   uintptr_t IntPtr = 0;
1700   if (Error E = OwningObject->getRvaPtr(Table[Index].Name, IntPtr,
1701                                         "delay import directory name"))
1702     return E;
1703   Result = StringRef(reinterpret_cast<const char *>(IntPtr));
1704   return Error::success();
1705 }
1706 
1707 Error DelayImportDirectoryEntryRef::getDelayImportTable(
1708     const delay_import_directory_table_entry *&Result) const {
1709   Result = &Table[Index];
1710   return Error::success();
1711 }
1712 
1713 Error DelayImportDirectoryEntryRef::getImportAddress(int AddrIndex,
1714                                                      uint64_t &Result) const {
1715   uint32_t RVA = Table[Index].DelayImportAddressTable +
1716       AddrIndex * (OwningObject->is64() ? 8 : 4);
1717   uintptr_t IntPtr = 0;
1718   if (Error E = OwningObject->getRvaPtr(RVA, IntPtr, "import address"))
1719     return E;
1720   if (OwningObject->is64())
1721     Result = *reinterpret_cast<const ulittle64_t *>(IntPtr);
1722   else
1723     Result = *reinterpret_cast<const ulittle32_t *>(IntPtr);
1724   return Error::success();
1725 }
1726 
1727 bool ExportDirectoryEntryRef::
1728 operator==(const ExportDirectoryEntryRef &Other) const {
1729   return ExportTable == Other.ExportTable && Index == Other.Index;
1730 }
1731 
1732 void ExportDirectoryEntryRef::moveNext() {
1733   ++Index;
1734 }
1735 
1736 // Returns the name of the current export symbol. If the symbol is exported only
1737 // by ordinal, the empty string is set as a result.
1738 Error ExportDirectoryEntryRef::getDllName(StringRef &Result) const {
1739   uintptr_t IntPtr = 0;
1740   if (Error E =
1741           OwningObject->getRvaPtr(ExportTable->NameRVA, IntPtr, "dll name"))
1742     return E;
1743   Result = StringRef(reinterpret_cast<const char *>(IntPtr));
1744   return Error::success();
1745 }
1746 
1747 // Returns the starting ordinal number.
1748 Error ExportDirectoryEntryRef::getOrdinalBase(uint32_t &Result) const {
1749   Result = ExportTable->OrdinalBase;
1750   return Error::success();
1751 }
1752 
1753 // Returns the export ordinal of the current export symbol.
1754 Error ExportDirectoryEntryRef::getOrdinal(uint32_t &Result) const {
1755   Result = ExportTable->OrdinalBase + Index;
1756   return Error::success();
1757 }
1758 
1759 // Returns the address of the current export symbol.
1760 Error ExportDirectoryEntryRef::getExportRVA(uint32_t &Result) const {
1761   uintptr_t IntPtr = 0;
1762   if (Error EC = OwningObject->getRvaPtr(ExportTable->ExportAddressTableRVA,
1763                                          IntPtr, "export address"))
1764     return EC;
1765   const export_address_table_entry *entry =
1766       reinterpret_cast<const export_address_table_entry *>(IntPtr);
1767   Result = entry[Index].ExportRVA;
1768   return Error::success();
1769 }
1770 
1771 // Returns the name of the current export symbol. If the symbol is exported only
1772 // by ordinal, the empty string is set as a result.
1773 Error
1774 ExportDirectoryEntryRef::getSymbolName(StringRef &Result) const {
1775   uintptr_t IntPtr = 0;
1776   if (Error EC = OwningObject->getRvaPtr(ExportTable->OrdinalTableRVA, IntPtr,
1777                                          "export ordinal table"))
1778     return EC;
1779   const ulittle16_t *Start = reinterpret_cast<const ulittle16_t *>(IntPtr);
1780 
1781   uint32_t NumEntries = ExportTable->NumberOfNamePointers;
1782   int Offset = 0;
1783   for (const ulittle16_t *I = Start, *E = Start + NumEntries;
1784        I < E; ++I, ++Offset) {
1785     if (*I != Index)
1786       continue;
1787     if (Error EC = OwningObject->getRvaPtr(ExportTable->NamePointerRVA, IntPtr,
1788                                            "export table entry"))
1789       return EC;
1790     const ulittle32_t *NamePtr = reinterpret_cast<const ulittle32_t *>(IntPtr);
1791     if (Error EC = OwningObject->getRvaPtr(NamePtr[Offset], IntPtr,
1792                                            "export symbol name"))
1793       return EC;
1794     Result = StringRef(reinterpret_cast<const char *>(IntPtr));
1795     return Error::success();
1796   }
1797   Result = "";
1798   return Error::success();
1799 }
1800 
1801 Error ExportDirectoryEntryRef::isForwarder(bool &Result) const {
1802   const data_directory *DataEntry =
1803       OwningObject->getDataDirectory(COFF::EXPORT_TABLE);
1804   if (!DataEntry)
1805     return createStringError(object_error::parse_failed,
1806                              "export table missing");
1807   uint32_t RVA;
1808   if (auto EC = getExportRVA(RVA))
1809     return EC;
1810   uint32_t Begin = DataEntry->RelativeVirtualAddress;
1811   uint32_t End = DataEntry->RelativeVirtualAddress + DataEntry->Size;
1812   Result = (Begin <= RVA && RVA < End);
1813   return Error::success();
1814 }
1815 
1816 Error ExportDirectoryEntryRef::getForwardTo(StringRef &Result) const {
1817   uint32_t RVA;
1818   if (auto EC = getExportRVA(RVA))
1819     return EC;
1820   uintptr_t IntPtr = 0;
1821   if (auto EC = OwningObject->getRvaPtr(RVA, IntPtr, "export forward target"))
1822     return EC;
1823   Result = StringRef(reinterpret_cast<const char *>(IntPtr));
1824   return Error::success();
1825 }
1826 
1827 bool ImportedSymbolRef::
1828 operator==(const ImportedSymbolRef &Other) const {
1829   return Entry32 == Other.Entry32 && Entry64 == Other.Entry64
1830       && Index == Other.Index;
1831 }
1832 
1833 void ImportedSymbolRef::moveNext() {
1834   ++Index;
1835 }
1836 
1837 Error ImportedSymbolRef::getSymbolName(StringRef &Result) const {
1838   uint32_t RVA;
1839   if (Entry32) {
1840     // If a symbol is imported only by ordinal, it has no name.
1841     if (Entry32[Index].isOrdinal())
1842       return Error::success();
1843     RVA = Entry32[Index].getHintNameRVA();
1844   } else {
1845     if (Entry64[Index].isOrdinal())
1846       return Error::success();
1847     RVA = Entry64[Index].getHintNameRVA();
1848   }
1849   uintptr_t IntPtr = 0;
1850   if (Error EC = OwningObject->getRvaPtr(RVA, IntPtr, "import symbol name"))
1851     return EC;
1852   // +2 because the first two bytes is hint.
1853   Result = StringRef(reinterpret_cast<const char *>(IntPtr + 2));
1854   return Error::success();
1855 }
1856 
1857 Error ImportedSymbolRef::isOrdinal(bool &Result) const {
1858   if (Entry32)
1859     Result = Entry32[Index].isOrdinal();
1860   else
1861     Result = Entry64[Index].isOrdinal();
1862   return Error::success();
1863 }
1864 
1865 Error ImportedSymbolRef::getHintNameRVA(uint32_t &Result) const {
1866   if (Entry32)
1867     Result = Entry32[Index].getHintNameRVA();
1868   else
1869     Result = Entry64[Index].getHintNameRVA();
1870   return Error::success();
1871 }
1872 
1873 Error ImportedSymbolRef::getOrdinal(uint16_t &Result) const {
1874   uint32_t RVA;
1875   if (Entry32) {
1876     if (Entry32[Index].isOrdinal()) {
1877       Result = Entry32[Index].getOrdinal();
1878       return Error::success();
1879     }
1880     RVA = Entry32[Index].getHintNameRVA();
1881   } else {
1882     if (Entry64[Index].isOrdinal()) {
1883       Result = Entry64[Index].getOrdinal();
1884       return Error::success();
1885     }
1886     RVA = Entry64[Index].getHintNameRVA();
1887   }
1888   uintptr_t IntPtr = 0;
1889   if (Error EC = OwningObject->getRvaPtr(RVA, IntPtr, "import symbol ordinal"))
1890     return EC;
1891   Result = *reinterpret_cast<const ulittle16_t *>(IntPtr);
1892   return Error::success();
1893 }
1894 
1895 Expected<std::unique_ptr<COFFObjectFile>>
1896 ObjectFile::createCOFFObjectFile(MemoryBufferRef Object) {
1897   return COFFObjectFile::create(Object);
1898 }
1899 
1900 bool BaseRelocRef::operator==(const BaseRelocRef &Other) const {
1901   return Header == Other.Header && Index == Other.Index;
1902 }
1903 
1904 void BaseRelocRef::moveNext() {
1905   // Header->BlockSize is the size of the current block, including the
1906   // size of the header itself.
1907   uint32_t Size = sizeof(*Header) +
1908       sizeof(coff_base_reloc_block_entry) * (Index + 1);
1909   if (Size == Header->BlockSize) {
1910     // .reloc contains a list of base relocation blocks. Each block
1911     // consists of the header followed by entries. The header contains
1912     // how many entories will follow. When we reach the end of the
1913     // current block, proceed to the next block.
1914     Header = reinterpret_cast<const coff_base_reloc_block_header *>(
1915         reinterpret_cast<const uint8_t *>(Header) + Size);
1916     Index = 0;
1917   } else {
1918     ++Index;
1919   }
1920 }
1921 
1922 Error BaseRelocRef::getType(uint8_t &Type) const {
1923   auto *Entry = reinterpret_cast<const coff_base_reloc_block_entry *>(Header + 1);
1924   Type = Entry[Index].getType();
1925   return Error::success();
1926 }
1927 
1928 Error BaseRelocRef::getRVA(uint32_t &Result) const {
1929   auto *Entry = reinterpret_cast<const coff_base_reloc_block_entry *>(Header + 1);
1930   Result = Header->PageRVA + Entry[Index].getOffset();
1931   return Error::success();
1932 }
1933 
1934 bool DynamicRelocRef::operator==(const DynamicRelocRef &Other) const {
1935   return Header == Other.Header;
1936 }
1937 
1938 void DynamicRelocRef::moveNext() {
1939   switch (Obj->getDynamicRelocTable()->Version) {
1940   case 1:
1941     if (Obj->is64()) {
1942       auto H = reinterpret_cast<const coff_dynamic_relocation64 *>(Header);
1943       Header += sizeof(*H) + H->BaseRelocSize;
1944     } else {
1945       auto H = reinterpret_cast<const coff_dynamic_relocation32 *>(Header);
1946       Header += sizeof(*H) + H->BaseRelocSize;
1947     }
1948     break;
1949   case 2:
1950     if (Obj->is64()) {
1951       auto H = reinterpret_cast<const coff_dynamic_relocation64_v2 *>(Header);
1952       Header += H->HeaderSize + H->FixupInfoSize;
1953     } else {
1954       auto H = reinterpret_cast<const coff_dynamic_relocation32_v2 *>(Header);
1955       Header += H->HeaderSize + H->FixupInfoSize;
1956     }
1957     break;
1958   }
1959 }
1960 
1961 uint32_t DynamicRelocRef::getType() const {
1962   switch (Obj->getDynamicRelocTable()->Version) {
1963   case 1:
1964     if (Obj->is64()) {
1965       auto H = reinterpret_cast<const coff_dynamic_relocation64 *>(Header);
1966       return H->Symbol;
1967     } else {
1968       auto H = reinterpret_cast<const coff_dynamic_relocation32 *>(Header);
1969       return H->Symbol;
1970     }
1971     break;
1972   case 2:
1973     if (Obj->is64()) {
1974       auto H = reinterpret_cast<const coff_dynamic_relocation64_v2 *>(Header);
1975       return H->Symbol;
1976     } else {
1977       auto H = reinterpret_cast<const coff_dynamic_relocation32_v2 *>(Header);
1978       return H->Symbol;
1979     }
1980     break;
1981   default:
1982     llvm_unreachable("invalid version");
1983   }
1984 }
1985 
1986 void DynamicRelocRef::getContents(ArrayRef<uint8_t> &Ref) const {
1987   switch (Obj->getDynamicRelocTable()->Version) {
1988   case 1:
1989     if (Obj->is64()) {
1990       auto H = reinterpret_cast<const coff_dynamic_relocation64 *>(Header);
1991       Ref = ArrayRef(Header + sizeof(*H), H->BaseRelocSize);
1992     } else {
1993       auto H = reinterpret_cast<const coff_dynamic_relocation32 *>(Header);
1994       Ref = ArrayRef(Header + sizeof(*H), H->BaseRelocSize);
1995     }
1996     break;
1997   case 2:
1998     if (Obj->is64()) {
1999       auto H = reinterpret_cast<const coff_dynamic_relocation64_v2 *>(Header);
2000       Ref = ArrayRef(Header + H->HeaderSize, H->FixupInfoSize);
2001     } else {
2002       auto H = reinterpret_cast<const coff_dynamic_relocation32_v2 *>(Header);
2003       Ref = ArrayRef(Header + H->HeaderSize, H->FixupInfoSize);
2004     }
2005     break;
2006   }
2007 }
2008 
2009 Error DynamicRelocRef::validate() const {
2010   const coff_dynamic_reloc_table *Table = Obj->getDynamicRelocTable();
2011   size_t ContentsSize =
2012       reinterpret_cast<const uint8_t *>(Table + 1) + Table->Size - Header;
2013   size_t HeaderSize;
2014   if (Table->Version == 1)
2015     HeaderSize = Obj->is64() ? sizeof(coff_dynamic_relocation64)
2016                              : sizeof(coff_dynamic_relocation32);
2017   else
2018     HeaderSize = Obj->is64() ? sizeof(coff_dynamic_relocation64_v2)
2019                              : sizeof(coff_dynamic_relocation32_v2);
2020   if (HeaderSize > ContentsSize)
2021     return createStringError(object_error::parse_failed,
2022                              "Unexpected end of dynamic relocations data");
2023 
2024   if (Table->Version == 2) {
2025     size_t Size =
2026         Obj->is64()
2027             ? reinterpret_cast<const coff_dynamic_relocation64_v2 *>(Header)
2028                   ->HeaderSize
2029             : reinterpret_cast<const coff_dynamic_relocation32_v2 *>(Header)
2030                   ->HeaderSize;
2031     if (Size < HeaderSize || Size > ContentsSize)
2032       return createStringError(object_error::parse_failed,
2033                                "Invalid dynamic relocation header size (" +
2034                                    Twine(Size) + ")");
2035     HeaderSize = Size;
2036   }
2037 
2038   ArrayRef<uint8_t> Contents;
2039   getContents(Contents);
2040   if (Contents.size() > ContentsSize - HeaderSize)
2041     return createStringError(object_error::parse_failed,
2042                              "Too large dynamic relocation size (" +
2043                                  Twine(Contents.size()) + ")");
2044 
2045   switch (getType()) {
2046   case COFF::IMAGE_DYNAMIC_RELOCATION_ARM64X:
2047     for (auto Reloc : arm64x_relocs()) {
2048       if (Error E = Reloc.validate(Obj))
2049         return E;
2050     }
2051     break;
2052   }
2053 
2054   return Error::success();
2055 }
2056 
2057 arm64x_reloc_iterator DynamicRelocRef::arm64x_reloc_begin() const {
2058   assert(getType() == COFF::IMAGE_DYNAMIC_RELOCATION_ARM64X);
2059   ArrayRef<uint8_t> Content;
2060   getContents(Content);
2061   auto Header =
2062       reinterpret_cast<const coff_base_reloc_block_header *>(Content.begin());
2063   return arm64x_reloc_iterator(Arm64XRelocRef(Header));
2064 }
2065 
2066 arm64x_reloc_iterator DynamicRelocRef::arm64x_reloc_end() const {
2067   assert(getType() == COFF::IMAGE_DYNAMIC_RELOCATION_ARM64X);
2068   ArrayRef<uint8_t> Content;
2069   getContents(Content);
2070   auto Header =
2071       reinterpret_cast<const coff_base_reloc_block_header *>(Content.end());
2072   return arm64x_reloc_iterator(Arm64XRelocRef(Header, 0));
2073 }
2074 
2075 iterator_range<arm64x_reloc_iterator> DynamicRelocRef::arm64x_relocs() const {
2076   return make_range(arm64x_reloc_begin(), arm64x_reloc_end());
2077 }
2078 
2079 bool Arm64XRelocRef::operator==(const Arm64XRelocRef &Other) const {
2080   return Header == Other.Header && Index == Other.Index;
2081 }
2082 
2083 uint8_t Arm64XRelocRef::getEntrySize() const {
2084   switch (getType()) {
2085   case COFF::IMAGE_DVRT_ARM64X_FIXUP_TYPE_VALUE:
2086     return (1ull << getArg()) / sizeof(uint16_t) + 1;
2087   case COFF::IMAGE_DVRT_ARM64X_FIXUP_TYPE_DELTA:
2088     return 2;
2089   default:
2090     return 1;
2091   }
2092 }
2093 
2094 void Arm64XRelocRef::moveNext() {
2095   Index += getEntrySize();
2096   if (sizeof(*Header) + Index * sizeof(uint16_t) < Header->BlockSize &&
2097       !getReloc())
2098     ++Index; // Skip padding
2099   if (sizeof(*Header) + Index * sizeof(uint16_t) == Header->BlockSize) {
2100     // The end of the block, move to the next one.
2101     Header =
2102         reinterpret_cast<const coff_base_reloc_block_header *>(&getReloc());
2103     Index = 0;
2104   }
2105 }
2106 
2107 uint8_t Arm64XRelocRef::getSize() const {
2108   switch (getType()) {
2109   case COFF::IMAGE_DVRT_ARM64X_FIXUP_TYPE_ZEROFILL:
2110   case COFF::IMAGE_DVRT_ARM64X_FIXUP_TYPE_VALUE:
2111     return 1 << getArg();
2112   case COFF::IMAGE_DVRT_ARM64X_FIXUP_TYPE_DELTA:
2113     return sizeof(uint32_t);
2114   }
2115   llvm_unreachable("Unknown Arm64XFixupType enum");
2116 }
2117 
2118 uint64_t Arm64XRelocRef::getValue() const {
2119   auto Ptr = reinterpret_cast<const ulittle16_t *>(Header + 1) + Index + 1;
2120 
2121   switch (getType()) {
2122   case COFF::IMAGE_DVRT_ARM64X_FIXUP_TYPE_VALUE: {
2123     ulittle64_t Value(0);
2124     memcpy(&Value, Ptr, getSize());
2125     return Value;
2126   }
2127   case COFF::IMAGE_DVRT_ARM64X_FIXUP_TYPE_DELTA: {
2128     uint16_t arg = getArg();
2129     int delta = *Ptr;
2130 
2131     if (arg & 1)
2132       delta = -delta;
2133     delta *= (arg & 2) ? 8 : 4;
2134     return delta;
2135   }
2136   default:
2137     return 0;
2138   }
2139 }
2140 
2141 Error Arm64XRelocRef::validate(const COFFObjectFile *Obj) const {
2142   if (!Index) {
2143     const coff_dynamic_reloc_table *Table = Obj->getDynamicRelocTable();
2144     size_t ContentsSize = reinterpret_cast<const uint8_t *>(Table + 1) +
2145                           Table->Size -
2146                           reinterpret_cast<const uint8_t *>(Header);
2147     if (ContentsSize < sizeof(coff_base_reloc_block_header))
2148       return createStringError(object_error::parse_failed,
2149                                "Unexpected end of ARM64X relocations data");
2150     if (Header->BlockSize <= sizeof(*Header))
2151       return createStringError(object_error::parse_failed,
2152                                "ARM64X relocations block size (" +
2153                                    Twine(Header->BlockSize) + ") is too small");
2154     if (Header->BlockSize % sizeof(uint32_t))
2155       return createStringError(object_error::parse_failed,
2156                                "Unaligned ARM64X relocations block size (" +
2157                                    Twine(Header->BlockSize) + ")");
2158     if (Header->BlockSize > ContentsSize)
2159       return createStringError(object_error::parse_failed,
2160                                "ARM64X relocations block size (" +
2161                                    Twine(Header->BlockSize) + ") is too large");
2162     if (Header->PageRVA & 0xfff)
2163       return createStringError(object_error::parse_failed,
2164                                "Unaligned ARM64X relocations page RVA (" +
2165                                    Twine(Header->PageRVA) + ")");
2166   }
2167 
2168   switch ((getReloc() >> 12) & 3) {
2169   case COFF::IMAGE_DVRT_ARM64X_FIXUP_TYPE_ZEROFILL:
2170   case COFF::IMAGE_DVRT_ARM64X_FIXUP_TYPE_DELTA:
2171     break;
2172   case COFF::IMAGE_DVRT_ARM64X_FIXUP_TYPE_VALUE:
2173     if (!getArg())
2174       return createStringError(object_error::parse_failed,
2175                                "Invalid ARM64X relocation value size (0)");
2176     break;
2177   default:
2178     return createStringError(object_error::parse_failed,
2179                              "Invalid relocation type");
2180   }
2181 
2182   uint32_t RelocsSize =
2183       (Header->BlockSize - sizeof(*Header)) / sizeof(uint16_t);
2184   uint16_t EntrySize = getEntrySize();
2185   if (!getReloc() ||
2186       (Index + EntrySize + 1 < RelocsSize && !getReloc(EntrySize)))
2187     return createStringError(object_error::parse_failed,
2188                              "Unexpected ARM64X relocations terminator");
2189   if (Index + EntrySize > RelocsSize)
2190     return createStringError(object_error::parse_failed,
2191                              "Unexpected end of ARM64X relocations");
2192   if (getRVA() % getSize())
2193     return createStringError(object_error::parse_failed,
2194                              "Unaligned ARM64X relocation RVA (" +
2195                                  Twine(getRVA()) + ")");
2196   if (Header->PageRVA) {
2197     uintptr_t IntPtr;
2198     return Obj->getRvaPtr(getRVA() + getSize(), IntPtr, "ARM64X reloc");
2199   }
2200   return Error::success();
2201 }
2202 
2203 #define RETURN_IF_ERROR(Expr)                                                  \
2204   do {                                                                         \
2205     Error E = (Expr);                                                          \
2206     if (E)                                                                     \
2207       return std::move(E);                                                     \
2208   } while (0)
2209 
2210 Expected<ArrayRef<UTF16>>
2211 ResourceSectionRef::getDirStringAtOffset(uint32_t Offset) {
2212   BinaryStreamReader Reader = BinaryStreamReader(BBS);
2213   Reader.setOffset(Offset);
2214   uint16_t Length;
2215   RETURN_IF_ERROR(Reader.readInteger(Length));
2216   ArrayRef<UTF16> RawDirString;
2217   RETURN_IF_ERROR(Reader.readArray(RawDirString, Length));
2218   return RawDirString;
2219 }
2220 
2221 Expected<ArrayRef<UTF16>>
2222 ResourceSectionRef::getEntryNameString(const coff_resource_dir_entry &Entry) {
2223   return getDirStringAtOffset(Entry.Identifier.getNameOffset());
2224 }
2225 
2226 Expected<const coff_resource_dir_table &>
2227 ResourceSectionRef::getTableAtOffset(uint32_t Offset) {
2228   const coff_resource_dir_table *Table = nullptr;
2229 
2230   BinaryStreamReader Reader(BBS);
2231   Reader.setOffset(Offset);
2232   RETURN_IF_ERROR(Reader.readObject(Table));
2233   assert(Table != nullptr);
2234   return *Table;
2235 }
2236 
2237 Expected<const coff_resource_dir_entry &>
2238 ResourceSectionRef::getTableEntryAtOffset(uint32_t Offset) {
2239   const coff_resource_dir_entry *Entry = nullptr;
2240 
2241   BinaryStreamReader Reader(BBS);
2242   Reader.setOffset(Offset);
2243   RETURN_IF_ERROR(Reader.readObject(Entry));
2244   assert(Entry != nullptr);
2245   return *Entry;
2246 }
2247 
2248 Expected<const coff_resource_data_entry &>
2249 ResourceSectionRef::getDataEntryAtOffset(uint32_t Offset) {
2250   const coff_resource_data_entry *Entry = nullptr;
2251 
2252   BinaryStreamReader Reader(BBS);
2253   Reader.setOffset(Offset);
2254   RETURN_IF_ERROR(Reader.readObject(Entry));
2255   assert(Entry != nullptr);
2256   return *Entry;
2257 }
2258 
2259 Expected<const coff_resource_dir_table &>
2260 ResourceSectionRef::getEntrySubDir(const coff_resource_dir_entry &Entry) {
2261   assert(Entry.Offset.isSubDir());
2262   return getTableAtOffset(Entry.Offset.value());
2263 }
2264 
2265 Expected<const coff_resource_data_entry &>
2266 ResourceSectionRef::getEntryData(const coff_resource_dir_entry &Entry) {
2267   assert(!Entry.Offset.isSubDir());
2268   return getDataEntryAtOffset(Entry.Offset.value());
2269 }
2270 
2271 Expected<const coff_resource_dir_table &> ResourceSectionRef::getBaseTable() {
2272   return getTableAtOffset(0);
2273 }
2274 
2275 Expected<const coff_resource_dir_entry &>
2276 ResourceSectionRef::getTableEntry(const coff_resource_dir_table &Table,
2277                                   uint32_t Index) {
2278   if (Index >= (uint32_t)(Table.NumberOfNameEntries + Table.NumberOfIDEntries))
2279     return createStringError(object_error::parse_failed, "index out of range");
2280   const uint8_t *TablePtr = reinterpret_cast<const uint8_t *>(&Table);
2281   ptrdiff_t TableOffset = TablePtr - BBS.data().data();
2282   return getTableEntryAtOffset(TableOffset + sizeof(Table) +
2283                                Index * sizeof(coff_resource_dir_entry));
2284 }
2285 
2286 Error ResourceSectionRef::load(const COFFObjectFile *O) {
2287   for (const SectionRef &S : O->sections()) {
2288     Expected<StringRef> Name = S.getName();
2289     if (!Name)
2290       return Name.takeError();
2291 
2292     if (*Name == ".rsrc" || *Name == ".rsrc$01")
2293       return load(O, S);
2294   }
2295   return createStringError(object_error::parse_failed,
2296                            "no resource section found");
2297 }
2298 
2299 Error ResourceSectionRef::load(const COFFObjectFile *O, const SectionRef &S) {
2300   Obj = O;
2301   Section = S;
2302   Expected<StringRef> Contents = Section.getContents();
2303   if (!Contents)
2304     return Contents.takeError();
2305   BBS = BinaryByteStream(*Contents, llvm::endianness::little);
2306   const coff_section *COFFSect = Obj->getCOFFSection(Section);
2307   ArrayRef<coff_relocation> OrigRelocs = Obj->getRelocations(COFFSect);
2308   Relocs.reserve(OrigRelocs.size());
2309   for (const coff_relocation &R : OrigRelocs)
2310     Relocs.push_back(&R);
2311   llvm::sort(Relocs, [](const coff_relocation *A, const coff_relocation *B) {
2312     return A->VirtualAddress < B->VirtualAddress;
2313   });
2314   return Error::success();
2315 }
2316 
2317 Expected<StringRef>
2318 ResourceSectionRef::getContents(const coff_resource_data_entry &Entry) {
2319   if (!Obj)
2320     return createStringError(object_error::parse_failed, "no object provided");
2321 
2322   // Find a potential relocation at the DataRVA field (first member of
2323   // the coff_resource_data_entry struct).
2324   const uint8_t *EntryPtr = reinterpret_cast<const uint8_t *>(&Entry);
2325   ptrdiff_t EntryOffset = EntryPtr - BBS.data().data();
2326   coff_relocation RelocTarget{ulittle32_t(EntryOffset), ulittle32_t(0),
2327                               ulittle16_t(0)};
2328   auto RelocsForOffset =
2329       std::equal_range(Relocs.begin(), Relocs.end(), &RelocTarget,
2330                        [](const coff_relocation *A, const coff_relocation *B) {
2331                          return A->VirtualAddress < B->VirtualAddress;
2332                        });
2333 
2334   if (RelocsForOffset.first != RelocsForOffset.second) {
2335     // We found a relocation with the right offset. Check that it does have
2336     // the expected type.
2337     const coff_relocation &R = **RelocsForOffset.first;
2338     uint16_t RVAReloc;
2339     switch (Obj->getArch()) {
2340     case Triple::x86:
2341       RVAReloc = COFF::IMAGE_REL_I386_DIR32NB;
2342       break;
2343     case Triple::x86_64:
2344       RVAReloc = COFF::IMAGE_REL_AMD64_ADDR32NB;
2345       break;
2346     case Triple::thumb:
2347       RVAReloc = COFF::IMAGE_REL_ARM_ADDR32NB;
2348       break;
2349     case Triple::aarch64:
2350       RVAReloc = COFF::IMAGE_REL_ARM64_ADDR32NB;
2351       break;
2352     default:
2353       return createStringError(object_error::parse_failed,
2354                                "unsupported architecture");
2355     }
2356     if (R.Type != RVAReloc)
2357       return createStringError(object_error::parse_failed,
2358                                "unexpected relocation type");
2359     // Get the relocation's symbol
2360     Expected<COFFSymbolRef> Sym = Obj->getSymbol(R.SymbolTableIndex);
2361     if (!Sym)
2362       return Sym.takeError();
2363     // And the symbol's section
2364     Expected<const coff_section *> Section =
2365         Obj->getSection(Sym->getSectionNumber());
2366     if (!Section)
2367       return Section.takeError();
2368     // Add the initial value of DataRVA to the symbol's offset to find the
2369     // data it points at.
2370     uint64_t Offset = Entry.DataRVA + Sym->getValue();
2371     ArrayRef<uint8_t> Contents;
2372     if (Error E = Obj->getSectionContents(*Section, Contents))
2373       return E;
2374     if (Offset + Entry.DataSize > Contents.size())
2375       return createStringError(object_error::parse_failed,
2376                                "data outside of section");
2377     // Return a reference to the data inside the section.
2378     return StringRef(reinterpret_cast<const char *>(Contents.data()) + Offset,
2379                      Entry.DataSize);
2380   } else {
2381     // Relocatable objects need a relocation for the DataRVA field.
2382     if (Obj->isRelocatableObject())
2383       return createStringError(object_error::parse_failed,
2384                                "no relocation found for DataRVA");
2385 
2386     // Locate the section that contains the address that DataRVA points at.
2387     uint64_t VA = Entry.DataRVA + Obj->getImageBase();
2388     for (const SectionRef &S : Obj->sections()) {
2389       if (VA >= S.getAddress() &&
2390           VA + Entry.DataSize <= S.getAddress() + S.getSize()) {
2391         uint64_t Offset = VA - S.getAddress();
2392         Expected<StringRef> Contents = S.getContents();
2393         if (!Contents)
2394           return Contents.takeError();
2395         return Contents->substr(Offset, Entry.DataSize);
2396       }
2397     }
2398     return createStringError(object_error::parse_failed,
2399                              "address not found in image");
2400   }
2401 }
2402