Bug Summary

File:tools/lld/lib/ReaderWriter/MachO/MachONormalizedFileToAtoms.cpp
Warning:line 1160, column 7
6th function call argument is an uninitialized value

Annotated Source Code

Press '?' to see keyboard shortcuts

clang -cc1 -triple x86_64-pc-linux-gnu -analyze -disable-free -disable-llvm-verifier -discard-value-names -main-file-name MachONormalizedFileToAtoms.cpp -analyzer-store=region -analyzer-opt-analyze-nested-blocks -analyzer-checker=core -analyzer-checker=apiModeling -analyzer-checker=unix -analyzer-checker=deadcode -analyzer-checker=cplusplus -analyzer-checker=security.insecureAPI.UncheckedReturn -analyzer-checker=security.insecureAPI.getpw -analyzer-checker=security.insecureAPI.gets -analyzer-checker=security.insecureAPI.mktemp -analyzer-checker=security.insecureAPI.mkstemp -analyzer-checker=security.insecureAPI.vfork -analyzer-checker=nullability.NullPassedToNonnull -analyzer-checker=nullability.NullReturnedFromNonnull -analyzer-output plist -w -mrelocation-model pic -pic-level 2 -mthread-model posix -fmath-errno -masm-verbose -mconstructor-aliases -munwind-tables -fuse-init-array -target-cpu x86-64 -dwarf-column-info -debugger-tuning=gdb -momit-leaf-frame-pointer -ffunction-sections -fdata-sections -resource-dir /usr/lib/llvm-8/lib/clang/8.0.0 -D _DEBUG -D _GNU_SOURCE -D __STDC_CONSTANT_MACROS -D __STDC_FORMAT_MACROS -D __STDC_LIMIT_MACROS -I /build/llvm-toolchain-snapshot-8~svn345461/build-llvm/tools/lld/lib/ReaderWriter/MachO -I /build/llvm-toolchain-snapshot-8~svn345461/tools/lld/lib/ReaderWriter/MachO -I /build/llvm-toolchain-snapshot-8~svn345461/tools/lld/include -I /build/llvm-toolchain-snapshot-8~svn345461/build-llvm/tools/lld/include -I /build/llvm-toolchain-snapshot-8~svn345461/build-llvm/include -I /build/llvm-toolchain-snapshot-8~svn345461/include -I /build/llvm-toolchain-snapshot-8~svn345461/tools/lld/lib/ReaderWriter/MachO/. -U NDEBUG -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/c++/6.3.0 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/x86_64-linux-gnu/c++/6.3.0 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/x86_64-linux-gnu/c++/6.3.0 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/c++/6.3.0/backward -internal-isystem /usr/include/clang/8.0.0/include/ -internal-isystem /usr/local/include -internal-isystem /usr/lib/llvm-8/lib/clang/8.0.0/include -internal-externc-isystem /usr/include/x86_64-linux-gnu -internal-externc-isystem /include -internal-externc-isystem /usr/include -O2 -Wno-unused-parameter -Wwrite-strings -Wno-missing-field-initializers -Wno-long-long -Wno-maybe-uninitialized -Wno-comment -std=c++11 -fdeprecated-macro -fdebug-compilation-dir /build/llvm-toolchain-snapshot-8~svn345461/build-llvm/tools/lld/lib/ReaderWriter/MachO -ferror-limit 19 -fmessage-length 0 -fvisibility-inlines-hidden -fobjc-runtime=gcc -fdiagnostics-show-option -vectorize-loops -vectorize-slp -analyzer-output=html -analyzer-config stable-report-filename=true -o /tmp/scan-build-2018-10-27-211344-32123-1 -x c++ /build/llvm-toolchain-snapshot-8~svn345461/tools/lld/lib/ReaderWriter/MachO/MachONormalizedFileToAtoms.cpp -faddrsig
1//===- lib/ReaderWriter/MachO/MachONormalizedFileToAtoms.cpp --------------===//
2//
3// The LLVM Linker
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9
10///
11/// \file Converts from in-memory normalized mach-o to in-memory Atoms.
12///
13/// +------------+
14/// | normalized |
15/// +------------+
16/// |
17/// |
18/// v
19/// +-------+
20/// | Atoms |
21/// +-------+
22
23#include "ArchHandler.h"
24#include "Atoms.h"
25#include "File.h"
26#include "MachONormalizedFile.h"
27#include "MachONormalizedFileBinaryUtils.h"
28#include "lld/Common/LLVM.h"
29#include "lld/Core/Error.h"
30#include "llvm/BinaryFormat/Dwarf.h"
31#include "llvm/BinaryFormat/MachO.h"
32#include "llvm/DebugInfo/DWARF/DWARFFormValue.h"
33#include "llvm/Support/DataExtractor.h"
34#include "llvm/Support/Debug.h"
35#include "llvm/Support/Error.h"
36#include "llvm/Support/Format.h"
37#include "llvm/Support/LEB128.h"
38#include "llvm/Support/raw_ostream.h"
39
40using namespace llvm::MachO;
41using namespace lld::mach_o::normalized;
42
43#define DEBUG_TYPE"normalized-file-to-atoms" "normalized-file-to-atoms"
44
45namespace lld {
46namespace mach_o {
47
48
49namespace { // anonymous
50
51
52#define ENTRY(seg, sect, type, atomType) \
53 {seg, sect, type, DefinedAtom::atomType }
54
55struct MachORelocatableSectionToAtomType {
56 StringRef segmentName;
57 StringRef sectionName;
58 SectionType sectionType;
59 DefinedAtom::ContentType atomType;
60};
61
62const MachORelocatableSectionToAtomType sectsToAtomType[] = {
63 ENTRY("__TEXT", "__text", S_REGULAR, typeCode),
64 ENTRY("__TEXT", "__text", S_REGULAR, typeResolver),
65 ENTRY("__TEXT", "__cstring", S_CSTRING_LITERALS, typeCString),
66 ENTRY("", "", S_CSTRING_LITERALS, typeCString),
67 ENTRY("__TEXT", "__ustring", S_REGULAR, typeUTF16String),
68 ENTRY("__TEXT", "__const", S_REGULAR, typeConstant),
69 ENTRY("__TEXT", "__const_coal", S_COALESCED, typeConstant),
70 ENTRY("__TEXT", "__eh_frame", S_COALESCED, typeCFI),
71 ENTRY("__TEXT", "__eh_frame", S_REGULAR, typeCFI),
72 ENTRY("__TEXT", "__literal4", S_4BYTE_LITERALS, typeLiteral4),
73 ENTRY("__TEXT", "__literal8", S_8BYTE_LITERALS, typeLiteral8),
74 ENTRY("__TEXT", "__literal16", S_16BYTE_LITERALS, typeLiteral16),
75 ENTRY("__TEXT", "__gcc_except_tab", S_REGULAR, typeLSDA),
76 ENTRY("__DATA", "__data", S_REGULAR, typeData),
77 ENTRY("__DATA", "__datacoal_nt", S_COALESCED, typeData),
78 ENTRY("__DATA", "__const", S_REGULAR, typeConstData),
79 ENTRY("__DATA", "__cfstring", S_REGULAR, typeCFString),
80 ENTRY("__DATA", "__mod_init_func", S_MOD_INIT_FUNC_POINTERS,
81 typeInitializerPtr),
82 ENTRY("__DATA", "__mod_term_func", S_MOD_TERM_FUNC_POINTERS,
83 typeTerminatorPtr),
84 ENTRY("__DATA", "__got", S_NON_LAZY_SYMBOL_POINTERS,
85 typeGOT),
86 ENTRY("__DATA", "__bss", S_ZEROFILL, typeZeroFill),
87 ENTRY("", "", S_NON_LAZY_SYMBOL_POINTERS,
88 typeGOT),
89 ENTRY("__DATA", "__interposing", S_INTERPOSING, typeInterposingTuples),
90 ENTRY("__DATA", "__thread_vars", S_THREAD_LOCAL_VARIABLES,
91 typeThunkTLV),
92 ENTRY("__DATA", "__thread_data", S_THREAD_LOCAL_REGULAR, typeTLVInitialData),
93 ENTRY("__DATA", "__thread_bss", S_THREAD_LOCAL_ZEROFILL,
94 typeTLVInitialZeroFill),
95 ENTRY("__DATA", "__objc_imageinfo", S_REGULAR, typeObjCImageInfo),
96 ENTRY("__DATA", "__objc_catlist", S_REGULAR, typeObjC2CategoryList),
97 ENTRY("", "", S_INTERPOSING, typeInterposingTuples),
98 ENTRY("__LD", "__compact_unwind", S_REGULAR,
99 typeCompactUnwindInfo),
100 ENTRY("", "", S_REGULAR, typeUnknown)
101};
102#undef ENTRY
103
104
105/// Figures out ContentType of a mach-o section.
106DefinedAtom::ContentType atomTypeFromSection(const Section &section,
107 bool &customSectionName) {
108 // First look for match of name and type. Empty names in table are wildcards.
109 customSectionName = false;
110 for (const MachORelocatableSectionToAtomType *p = sectsToAtomType ;
111 p->atomType != DefinedAtom::typeUnknown; ++p) {
112 if (p->sectionType != section.type)
113 continue;
114 if (!p->segmentName.equals(section.segmentName) && !p->segmentName.empty())
115 continue;
116 if (!p->sectionName.equals(section.sectionName) && !p->sectionName.empty())
117 continue;
118 customSectionName = p->segmentName.empty() && p->sectionName.empty();
119 return p->atomType;
120 }
121 // Look for code denoted by section attributes
122 if (section.attributes & S_ATTR_PURE_INSTRUCTIONS)
123 return DefinedAtom::typeCode;
124
125 return DefinedAtom::typeUnknown;
126}
127
128enum AtomizeModel {
129 atomizeAtSymbols,
130 atomizeFixedSize,
131 atomizePointerSize,
132 atomizeUTF8,
133 atomizeUTF16,
134 atomizeCFI,
135 atomizeCU,
136 atomizeCFString
137};
138
139/// Returns info on how to atomize a section of the specified ContentType.
140void sectionParseInfo(DefinedAtom::ContentType atomType,
141 unsigned int &sizeMultiple,
142 DefinedAtom::Scope &scope,
143 DefinedAtom::Merge &merge,
144 AtomizeModel &atomizeModel) {
145 struct ParseInfo {
146 DefinedAtom::ContentType atomType;
147 unsigned int sizeMultiple;
148 DefinedAtom::Scope scope;
149 DefinedAtom::Merge merge;
150 AtomizeModel atomizeModel;
151 };
152
153 #define ENTRY(type, size, scope, merge, model) \
154 {DefinedAtom::type, size, DefinedAtom::scope, DefinedAtom::merge, model }
155
156 static const ParseInfo parseInfo[] = {
157 ENTRY(typeCode, 1, scopeGlobal, mergeNo,
158 atomizeAtSymbols),
159 ENTRY(typeData, 1, scopeGlobal, mergeNo,
160 atomizeAtSymbols),
161 ENTRY(typeConstData, 1, scopeGlobal, mergeNo,
162 atomizeAtSymbols),
163 ENTRY(typeZeroFill, 1, scopeGlobal, mergeNo,
164 atomizeAtSymbols),
165 ENTRY(typeConstant, 1, scopeGlobal, mergeNo,
166 atomizeAtSymbols),
167 ENTRY(typeCString, 1, scopeLinkageUnit, mergeByContent,
168 atomizeUTF8),
169 ENTRY(typeUTF16String, 1, scopeLinkageUnit, mergeByContent,
170 atomizeUTF16),
171 ENTRY(typeCFI, 4, scopeTranslationUnit, mergeNo,
172 atomizeCFI),
173 ENTRY(typeLiteral4, 4, scopeLinkageUnit, mergeByContent,
174 atomizeFixedSize),
175 ENTRY(typeLiteral8, 8, scopeLinkageUnit, mergeByContent,
176 atomizeFixedSize),
177 ENTRY(typeLiteral16, 16, scopeLinkageUnit, mergeByContent,
178 atomizeFixedSize),
179 ENTRY(typeCFString, 4, scopeLinkageUnit, mergeByContent,
180 atomizeCFString),
181 ENTRY(typeInitializerPtr, 4, scopeTranslationUnit, mergeNo,
182 atomizePointerSize),
183 ENTRY(typeTerminatorPtr, 4, scopeTranslationUnit, mergeNo,
184 atomizePointerSize),
185 ENTRY(typeCompactUnwindInfo, 4, scopeTranslationUnit, mergeNo,
186 atomizeCU),
187 ENTRY(typeGOT, 4, scopeLinkageUnit, mergeByContent,
188 atomizePointerSize),
189 ENTRY(typeObjC2CategoryList, 4, scopeTranslationUnit, mergeByContent,
190 atomizePointerSize),
191 ENTRY(typeUnknown, 1, scopeGlobal, mergeNo,
192 atomizeAtSymbols)
193 };
194 #undef ENTRY
195 const int tableLen = sizeof(parseInfo) / sizeof(ParseInfo);
196 for (int i=0; i < tableLen; ++i) {
197 if (parseInfo[i].atomType == atomType) {
198 sizeMultiple = parseInfo[i].sizeMultiple;
199 scope = parseInfo[i].scope;
200 merge = parseInfo[i].merge;
201 atomizeModel = parseInfo[i].atomizeModel;
202 return;
203 }
204 }
205
206 // Unknown type is atomized by symbols.
207 sizeMultiple = 1;
208 scope = DefinedAtom::scopeGlobal;
209 merge = DefinedAtom::mergeNo;
210 atomizeModel = atomizeAtSymbols;
211}
212
213
214Atom::Scope atomScope(uint8_t scope) {
215 switch (scope) {
216 case N_EXT:
217 return Atom::scopeGlobal;
218 case N_PEXT:
219 case N_PEXT | N_EXT:
220 return Atom::scopeLinkageUnit;
221 case 0:
222 return Atom::scopeTranslationUnit;
223 }
224 llvm_unreachable("unknown scope value!")::llvm::llvm_unreachable_internal("unknown scope value!", "/build/llvm-toolchain-snapshot-8~svn345461/tools/lld/lib/ReaderWriter/MachO/MachONormalizedFileToAtoms.cpp"
, 224)
;
225}
226
227void appendSymbolsInSection(const std::vector<Symbol> &inSymbols,
228 uint32_t sectionIndex,
229 SmallVector<const Symbol *, 64> &outSyms) {
230 for (const Symbol &sym : inSymbols) {
231 // Only look at definition symbols.
232 if ((sym.type & N_TYPE) != N_SECT)
233 continue;
234 if (sym.sect != sectionIndex)
235 continue;
236 outSyms.push_back(&sym);
237 }
238}
239
240void atomFromSymbol(DefinedAtom::ContentType atomType, const Section &section,
241 MachOFile &file, uint64_t symbolAddr, StringRef symbolName,
242 uint16_t symbolDescFlags, Atom::Scope symbolScope,
243 uint64_t nextSymbolAddr, bool scatterable, bool copyRefs) {
244 // Mach-O symbol table does have size in it. Instead the size is the
245 // difference between this and the next symbol.
246 uint64_t size = nextSymbolAddr - symbolAddr;
247 uint64_t offset = symbolAddr - section.address;
248 bool noDeadStrip = (symbolDescFlags & N_NO_DEAD_STRIP) || !scatterable;
249 if (isZeroFillSection(section.type)) {
250 file.addZeroFillDefinedAtom(symbolName, symbolScope, offset, size,
251 noDeadStrip, copyRefs, &section);
252 } else {
253 DefinedAtom::Merge merge = (symbolDescFlags & N_WEAK_DEF)
254 ? DefinedAtom::mergeAsWeak : DefinedAtom::mergeNo;
255 bool thumb = (symbolDescFlags & N_ARM_THUMB_DEF);
256 if (atomType == DefinedAtom::typeUnknown) {
257 // Mach-O needs a segment and section name. Concatentate those two
258 // with a / separator (e.g. "seg/sect") to fit into the lld model
259 // of just a section name.
260 std::string segSectName = section.segmentName.str()
261 + "/" + section.sectionName.str();
262 file.addDefinedAtomInCustomSection(symbolName, symbolScope, atomType,
263 merge, thumb, noDeadStrip, offset,
264 size, segSectName, true, &section);
265 } else {
266 if ((atomType == lld::DefinedAtom::typeCode) &&
267 (symbolDescFlags & N_SYMBOL_RESOLVER)) {
268 atomType = lld::DefinedAtom::typeResolver;
269 }
270 file.addDefinedAtom(symbolName, symbolScope, atomType, merge,
271 offset, size, thumb, noDeadStrip, copyRefs, &section);
272 }
273 }
274}
275
276llvm::Error processSymboledSection(DefinedAtom::ContentType atomType,
277 const Section &section,
278 const NormalizedFile &normalizedFile,
279 MachOFile &file, bool scatterable,
280 bool copyRefs) {
281 // Find section's index.
282 uint32_t sectIndex = 1;
283 for (auto &sect : normalizedFile.sections) {
284 if (&sect == &section)
285 break;
286 ++sectIndex;
287 }
288
289 // Find all symbols in this section.
290 SmallVector<const Symbol *, 64> symbols;
291 appendSymbolsInSection(normalizedFile.globalSymbols, sectIndex, symbols);
292 appendSymbolsInSection(normalizedFile.localSymbols, sectIndex, symbols);
293
294 // Sort symbols.
295 std::sort(symbols.begin(), symbols.end(),
296 [](const Symbol *lhs, const Symbol *rhs) -> bool {
297 if (lhs == rhs)
298 return false;
299 // First by address.
300 uint64_t lhsAddr = lhs->value;
301 uint64_t rhsAddr = rhs->value;
302 if (lhsAddr != rhsAddr)
303 return lhsAddr < rhsAddr;
304 // If same address, one is an alias so sort by scope.
305 Atom::Scope lScope = atomScope(lhs->scope);
306 Atom::Scope rScope = atomScope(rhs->scope);
307 if (lScope != rScope)
308 return lScope < rScope;
309 // If same address and scope, see if one might be better as
310 // the alias.
311 bool lPrivate = (lhs->name.front() == 'l');
312 bool rPrivate = (rhs->name.front() == 'l');
313 if (lPrivate != rPrivate)
314 return lPrivate;
315 // If same address and scope, sort by name.
316 return lhs->name < rhs->name;
317 });
318
319 // Debug logging of symbols.
320 //for (const Symbol *sym : symbols)
321 // llvm::errs() << " sym: "
322 // << llvm::format("0x%08llx ", (uint64_t)sym->value)
323 // << ", " << sym->name << "\n";
324
325 // If section has no symbols and no content, there are no atoms.
326 if (symbols.empty() && section.content.empty())
327 return llvm::Error::success();
328
329 if (symbols.empty()) {
330 // Section has no symbols, put all content in one anoymous atom.
331 atomFromSymbol(atomType, section, file, section.address, StringRef(),
332 0, Atom::scopeTranslationUnit,
333 section.address + section.content.size(),
334 scatterable, copyRefs);
335 }
336 else if (symbols.front()->value != section.address) {
337 // Section has anonymous content before first symbol.
338 atomFromSymbol(atomType, section, file, section.address, StringRef(),
339 0, Atom::scopeTranslationUnit, symbols.front()->value,
340 scatterable, copyRefs);
341 }
342
343 const Symbol *lastSym = nullptr;
344 for (const Symbol *sym : symbols) {
345 if (lastSym != nullptr) {
346 // Ignore any assembler added "ltmpNNN" symbol at start of section
347 // if there is another symbol at the start.
348 if ((lastSym->value != sym->value)
349 || lastSym->value != section.address
350 || !lastSym->name.startswith("ltmp")) {
351 atomFromSymbol(atomType, section, file, lastSym->value, lastSym->name,
352 lastSym->desc, atomScope(lastSym->scope), sym->value,
353 scatterable, copyRefs);
354 }
355 }
356 lastSym = sym;
357 }
358 if (lastSym != nullptr) {
359 atomFromSymbol(atomType, section, file, lastSym->value, lastSym->name,
360 lastSym->desc, atomScope(lastSym->scope),
361 section.address + section.content.size(),
362 scatterable, copyRefs);
363 }
364
365 // If object built without .subsections_via_symbols, add reference chain.
366 if (!scatterable) {
367 MachODefinedAtom *prevAtom = nullptr;
368 file.eachAtomInSection(section,
369 [&](MachODefinedAtom *atom, uint64_t offset)->void {
370 if (prevAtom)
371 prevAtom->addReference(Reference::KindNamespace::all,
372 Reference::KindArch::all,
373 Reference::kindLayoutAfter, 0, atom, 0);
374 prevAtom = atom;
375 });
376 }
377
378 return llvm::Error::success();
379}
380
381llvm::Error processSection(DefinedAtom::ContentType atomType,
382 const Section &section,
383 bool customSectionName,
384 const NormalizedFile &normalizedFile,
385 MachOFile &file, bool scatterable,
386 bool copyRefs) {
387 const bool is64 = MachOLinkingContext::is64Bit(normalizedFile.arch);
388 const bool isBig = MachOLinkingContext::isBigEndian(normalizedFile.arch);
389
390 // Get info on how to atomize section.
391 unsigned int sizeMultiple;
392 DefinedAtom::Scope scope;
393 DefinedAtom::Merge merge;
394 AtomizeModel atomizeModel;
395 sectionParseInfo(atomType, sizeMultiple, scope, merge, atomizeModel);
396
397 // Validate section size.
398 if ((section.content.size() % sizeMultiple) != 0)
399 return llvm::make_error<GenericError>(Twine("Section ")
400 + section.segmentName
401 + "/" + section.sectionName
402 + " has size ("
403 + Twine(section.content.size())
404 + ") which is not a multiple of "
405 + Twine(sizeMultiple));
406
407 if (atomizeModel == atomizeAtSymbols) {
408 // Break section up into atoms each with a fixed size.
409 return processSymboledSection(atomType, section, normalizedFile, file,
410 scatterable, copyRefs);
411 } else {
412 unsigned int size;
413 for (unsigned int offset = 0, e = section.content.size(); offset != e;) {
414 switch (atomizeModel) {
415 case atomizeFixedSize:
416 // Break section up into atoms each with a fixed size.
417 size = sizeMultiple;
418 break;
419 case atomizePointerSize:
420 // Break section up into atoms each the size of a pointer.
421 size = is64 ? 8 : 4;
422 break;
423 case atomizeUTF8:
424 // Break section up into zero terminated c-strings.
425 size = 0;
426 for (unsigned int i = offset; i < e; ++i) {
427 if (section.content[i] == 0) {
428 size = i + 1 - offset;
429 break;
430 }
431 }
432 break;
433 case atomizeUTF16:
434 // Break section up into zero terminated UTF16 strings.
435 size = 0;
436 for (unsigned int i = offset; i < e; i += 2) {
437 if ((section.content[i] == 0) && (section.content[i + 1] == 0)) {
438 size = i + 2 - offset;
439 break;
440 }
441 }
442 break;
443 case atomizeCFI:
444 // Break section up into dwarf unwind CFIs (FDE or CIE).
445 size = read32(&section.content[offset], isBig) + 4;
446 if (offset+size > section.content.size()) {
447 return llvm::make_error<GenericError>(Twine("Section ")
448 + section.segmentName
449 + "/" + section.sectionName
450 + " is malformed. Size of CFI "
451 "starting at offset ("
452 + Twine(offset)
453 + ") is past end of section.");
454 }
455 break;
456 case atomizeCU:
457 // Break section up into compact unwind entries.
458 size = is64 ? 32 : 20;
459 break;
460 case atomizeCFString:
461 // Break section up into NS/CFString objects.
462 size = is64 ? 32 : 16;
463 break;
464 case atomizeAtSymbols:
465 break;
466 }
467 if (size == 0) {
468 return llvm::make_error<GenericError>(Twine("Section ")
469 + section.segmentName
470 + "/" + section.sectionName
471 + " is malformed. The last atom "
472 "is not zero terminated.");
473 }
474 if (customSectionName) {
475 // Mach-O needs a segment and section name. Concatentate those two
476 // with a / separator (e.g. "seg/sect") to fit into the lld model
477 // of just a section name.
478 std::string segSectName = section.segmentName.str()
479 + "/" + section.sectionName.str();
480 file.addDefinedAtomInCustomSection(StringRef(), scope, atomType,
481 merge, false, false, offset,
482 size, segSectName, true, &section);
483 } else {
484 file.addDefinedAtom(StringRef(), scope, atomType, merge, offset, size,
485 false, false, copyRefs, &section);
486 }
487 offset += size;
488 }
489 }
490 return llvm::Error::success();
491}
492
493const Section* findSectionCoveringAddress(const NormalizedFile &normalizedFile,
494 uint64_t address) {
495 for (const Section &s : normalizedFile.sections) {
496 uint64_t sAddr = s.address;
497 if ((sAddr <= address) && (address < sAddr+s.content.size())) {
498 return &s;
499 }
500 }
501 return nullptr;
502}
503
504const MachODefinedAtom *
505findAtomCoveringAddress(const NormalizedFile &normalizedFile, MachOFile &file,
506 uint64_t addr, Reference::Addend &addend) {
507 const Section *sect = nullptr;
508 sect = findSectionCoveringAddress(normalizedFile, addr);
509 if (!sect)
15
Assuming 'sect' is null
16
Taking true branch
510 return nullptr;
17
Returning without writing to 'addend'
511
512 uint32_t offsetInTarget;
513 uint64_t offsetInSect = addr - sect->address;
514 auto atom =
515 file.findAtomCoveringAddress(*sect, offsetInSect, &offsetInTarget);
516 addend = offsetInTarget;
517 return atom;
518}
519
520// Walks all relocations for a section in a normalized .o file and
521// creates corresponding lld::Reference objects.
522llvm::Error convertRelocs(const Section &section,
523 const NormalizedFile &normalizedFile,
524 bool scatterable,
525 MachOFile &file,
526 ArchHandler &handler) {
527 // Utility function for ArchHandler to find atom by its address.
528 auto atomByAddr = [&] (uint32_t sectIndex, uint64_t addr,
529 const lld::Atom **atom, Reference::Addend *addend)
530 -> llvm::Error {
531 if (sectIndex > normalizedFile.sections.size())
532 return llvm::make_error<GenericError>(Twine("out of range section "
533 "index (") + Twine(sectIndex) + ")");
534 const Section *sect = nullptr;
535 if (sectIndex == 0) {
536 sect = findSectionCoveringAddress(normalizedFile, addr);
537 if (!sect)
538 return llvm::make_error<GenericError>(Twine("address (" + Twine(addr)
539 + ") is not in any section"));
540 } else {
541 sect = &normalizedFile.sections[sectIndex-1];
542 }
543 uint32_t offsetInTarget;
544 uint64_t offsetInSect = addr - sect->address;
545 *atom = file.findAtomCoveringAddress(*sect, offsetInSect, &offsetInTarget);
546 *addend = offsetInTarget;
547 return llvm::Error::success();
548 };
549
550 // Utility function for ArchHandler to find atom by its symbol index.
551 auto atomBySymbol = [&] (uint32_t symbolIndex, const lld::Atom **result)
552 -> llvm::Error {
553 // Find symbol from index.
554 const Symbol *sym = nullptr;
555 uint32_t numStabs = normalizedFile.stabsSymbols.size();
556 uint32_t numLocal = normalizedFile.localSymbols.size();
557 uint32_t numGlobal = normalizedFile.globalSymbols.size();
558 uint32_t numUndef = normalizedFile.undefinedSymbols.size();
559 assert(symbolIndex >= numStabs && "Searched for stab via atomBySymbol?")((symbolIndex >= numStabs && "Searched for stab via atomBySymbol?"
) ? static_cast<void> (0) : __assert_fail ("symbolIndex >= numStabs && \"Searched for stab via atomBySymbol?\""
, "/build/llvm-toolchain-snapshot-8~svn345461/tools/lld/lib/ReaderWriter/MachO/MachONormalizedFileToAtoms.cpp"
, 559, __PRETTY_FUNCTION__))
;
560 if (symbolIndex < numStabs+numLocal) {
561 sym = &normalizedFile.localSymbols[symbolIndex-numStabs];
562 } else if (symbolIndex < numStabs+numLocal+numGlobal) {
563 sym = &normalizedFile.globalSymbols[symbolIndex-numStabs-numLocal];
564 } else if (symbolIndex < numStabs+numLocal+numGlobal+numUndef) {
565 sym = &normalizedFile.undefinedSymbols[symbolIndex-numStabs-numLocal-
566 numGlobal];
567 } else {
568 return llvm::make_error<GenericError>(Twine("symbol index (")
569 + Twine(symbolIndex) + ") out of range");
570 }
571
572 // Find atom from symbol.
573 if ((sym->type & N_TYPE) == N_SECT) {
574 if (sym->sect > normalizedFile.sections.size())
575 return llvm::make_error<GenericError>(Twine("symbol section index (")
576 + Twine(sym->sect) + ") out of range ");
577 const Section &symSection = normalizedFile.sections[sym->sect-1];
578 uint64_t targetOffsetInSect = sym->value - symSection.address;
579 MachODefinedAtom *target = file.findAtomCoveringAddress(symSection,
580 targetOffsetInSect);
581 if (target) {
582 *result = target;
583 return llvm::Error::success();
584 }
585 return llvm::make_error<GenericError>("no atom found for defined symbol");
586 } else if ((sym->type & N_TYPE) == N_UNDF) {
587 const lld::Atom *target = file.findUndefAtom(sym->name);
588 if (target) {
589 *result = target;
590 return llvm::Error::success();
591 }
592 return llvm::make_error<GenericError>("no undefined atom found for sym");
593 } else {
594 // Search undefs
595 return llvm::make_error<GenericError>("no atom found for symbol");
596 }
597 };
598
599 const bool isBig = MachOLinkingContext::isBigEndian(normalizedFile.arch);
600 // Use old-school iterator so that paired relocations can be grouped.
601 for (auto it=section.relocations.begin(), e=section.relocations.end();
602 it != e; ++it) {
603 const Relocation &reloc = *it;
604 // Find atom this relocation is in.
605 if (reloc.offset > section.content.size())
606 return llvm::make_error<GenericError>(
607 Twine("r_address (") + Twine(reloc.offset)
608 + ") is larger than section size ("
609 + Twine(section.content.size()) + ")");
610 uint32_t offsetInAtom;
611 MachODefinedAtom *inAtom = file.findAtomCoveringAddress(section,
612 reloc.offset,
613 &offsetInAtom);
614 assert(inAtom && "r_address in range, should have found atom")((inAtom && "r_address in range, should have found atom"
) ? static_cast<void> (0) : __assert_fail ("inAtom && \"r_address in range, should have found atom\""
, "/build/llvm-toolchain-snapshot-8~svn345461/tools/lld/lib/ReaderWriter/MachO/MachONormalizedFileToAtoms.cpp"
, 614, __PRETTY_FUNCTION__))
;
615 uint64_t fixupAddress = section.address + reloc.offset;
616
617 const lld::Atom *target = nullptr;
618 Reference::Addend addend = 0;
619 Reference::KindValue kind;
620 if (handler.isPairedReloc(reloc)) {
621 // Handle paired relocations together.
622 const Relocation &reloc2 = *++it;
623 auto relocErr = handler.getPairReferenceInfo(
624 reloc, reloc2, inAtom, offsetInAtom, fixupAddress, isBig, scatterable,
625 atomByAddr, atomBySymbol, &kind, &target, &addend);
626 if (relocErr) {
627 return handleErrors(std::move(relocErr),
628 [&](std::unique_ptr<GenericError> GE) {
629 return llvm::make_error<GenericError>(
630 Twine("bad relocation (") + GE->getMessage()
631 + ") in section "
632 + section.segmentName + "/" + section.sectionName
633 + " (r1_address=" + Twine::utohexstr(reloc.offset)
634 + ", r1_type=" + Twine(reloc.type)
635 + ", r1_extern=" + Twine(reloc.isExtern)
636 + ", r1_length=" + Twine((int)reloc.length)
637 + ", r1_pcrel=" + Twine(reloc.pcRel)
638 + (!reloc.scattered ? (Twine(", r1_symbolnum=")
639 + Twine(reloc.symbol))
640 : (Twine(", r1_scattered=1, r1_value=")
641 + Twine(reloc.value)))
642 + ")"
643 + ", (r2_address=" + Twine::utohexstr(reloc2.offset)
644 + ", r2_type=" + Twine(reloc2.type)
645 + ", r2_extern=" + Twine(reloc2.isExtern)
646 + ", r2_length=" + Twine((int)reloc2.length)
647 + ", r2_pcrel=" + Twine(reloc2.pcRel)
648 + (!reloc2.scattered ? (Twine(", r2_symbolnum=")
649 + Twine(reloc2.symbol))
650 : (Twine(", r2_scattered=1, r2_value=")
651 + Twine(reloc2.value)))
652 + ")" );
653 });
654 }
655 }
656 else {
657 // Use ArchHandler to convert relocation record into information
658 // needed to instantiate an lld::Reference object.
659 auto relocErr = handler.getReferenceInfo(
660 reloc, inAtom, offsetInAtom, fixupAddress, isBig, atomByAddr,
661 atomBySymbol, &kind, &target, &addend);
662 if (relocErr) {
663 return handleErrors(std::move(relocErr),
664 [&](std::unique_ptr<GenericError> GE) {
665 return llvm::make_error<GenericError>(
666 Twine("bad relocation (") + GE->getMessage()
667 + ") in section "
668 + section.segmentName + "/" + section.sectionName
669 + " (r_address=" + Twine::utohexstr(reloc.offset)
670 + ", r_type=" + Twine(reloc.type)
671 + ", r_extern=" + Twine(reloc.isExtern)
672 + ", r_length=" + Twine((int)reloc.length)
673 + ", r_pcrel=" + Twine(reloc.pcRel)
674 + (!reloc.scattered ? (Twine(", r_symbolnum=") + Twine(reloc.symbol))
675 : (Twine(", r_scattered=1, r_value=")
676 + Twine(reloc.value)))
677 + ")" );
678 });
679 }
680 }
681 // Instantiate an lld::Reference object and add to its atom.
682 inAtom->addReference(Reference::KindNamespace::mach_o,
683 handler.kindArch(),
684 kind, offsetInAtom, target, addend);
685 }
686
687 return llvm::Error::success();
688}
689
690bool isDebugInfoSection(const Section &section) {
691 if ((section.attributes & S_ATTR_DEBUG) == 0)
692 return false;
693 return section.segmentName.equals("__DWARF");
694}
695
696static const Atom* findDefinedAtomByName(MachOFile &file, Twine name) {
697 std::string strName = name.str();
698 for (auto *atom : file.defined())
699 if (atom->name() == strName)
700 return atom;
701 return nullptr;
702}
703
704static StringRef copyDebugString(StringRef str, BumpPtrAllocator &alloc) {
705 char *strCopy = alloc.Allocate<char>(str.size() + 1);
706 memcpy(strCopy, str.data(), str.size());
707 strCopy[str.size()] = '\0';
708 return strCopy;
709}
710
711llvm::Error parseStabs(MachOFile &file,
712 const NormalizedFile &normalizedFile,
713 bool copyRefs) {
714
715 if (normalizedFile.stabsSymbols.empty())
716 return llvm::Error::success();
717
718 // FIXME: Kill this off when we can move to sane yaml parsing.
719 std::unique_ptr<BumpPtrAllocator> allocator;
720 if (copyRefs)
721 allocator = llvm::make_unique<BumpPtrAllocator>();
722
723 enum { start, inBeginEnd } state = start;
724
725 const Atom *currentAtom = nullptr;
726 uint64_t currentAtomAddress = 0;
727 StabsDebugInfo::StabsList stabsList;
728 for (const auto &stabSym : normalizedFile.stabsSymbols) {
729 Stab stab(nullptr, stabSym.type, stabSym.sect, stabSym.desc,
730 stabSym.value, stabSym.name);
731 switch (state) {
732 case start:
733 switch (static_cast<StabType>(stabSym.type)) {
734 case N_BNSYM:
735 state = inBeginEnd;
736 currentAtomAddress = stabSym.value;
737 Reference::Addend addend;
738 currentAtom = findAtomCoveringAddress(normalizedFile, file,
739 currentAtomAddress, addend);
740 if (addend != 0)
741 return llvm::make_error<GenericError>(
742 "Non-zero addend for BNSYM '" + stabSym.name + "' in " +
743 file.path());
744 if (currentAtom)
745 stab.atom = currentAtom;
746 else {
747 // FIXME: ld64 just issues a warning here - should we match that?
748 return llvm::make_error<GenericError>(
749 "can't find atom for stabs BNSYM at " +
750 Twine::utohexstr(stabSym.value) + " in " + file.path());
751 }
752 break;
753 case N_SO:
754 case N_OSO:
755 // Not associated with an atom, just copy.
756 if (copyRefs)
757 stab.str = copyDebugString(stabSym.name, *allocator);
758 else
759 stab.str = stabSym.name;
760 break;
761 case N_GSYM: {
762 auto colonIdx = stabSym.name.find(':');
763 if (colonIdx != StringRef::npos) {
764 StringRef name = stabSym.name.substr(0, colonIdx);
765 currentAtom = findDefinedAtomByName(file, "_" + name);
766 stab.atom = currentAtom;
767 if (copyRefs)
768 stab.str = copyDebugString(stabSym.name, *allocator);
769 else
770 stab.str = stabSym.name;
771 } else {
772 currentAtom = findDefinedAtomByName(file, stabSym.name);
773 stab.atom = currentAtom;
774 if (copyRefs)
775 stab.str = copyDebugString(stabSym.name, *allocator);
776 else
777 stab.str = stabSym.name;
778 }
779 if (stab.atom == nullptr)
780 return llvm::make_error<GenericError>(
781 "can't find atom for N_GSYM stabs" + stabSym.name +
782 " in " + file.path());
783 break;
784 }
785 case N_FUN:
786 return llvm::make_error<GenericError>(
787 "old-style N_FUN stab '" + stabSym.name + "' unsupported");
788 default:
789 return llvm::make_error<GenericError>(
790 "unrecognized stab symbol '" + stabSym.name + "'");
791 }
792 break;
793 case inBeginEnd:
794 stab.atom = currentAtom;
795 switch (static_cast<StabType>(stabSym.type)) {
796 case N_ENSYM:
797 state = start;
798 currentAtom = nullptr;
799 break;
800 case N_FUN:
801 // Just copy the string.
802 if (copyRefs)
803 stab.str = copyDebugString(stabSym.name, *allocator);
804 else
805 stab.str = stabSym.name;
806 break;
807 default:
808 return llvm::make_error<GenericError>(
809 "unrecognized stab symbol '" + stabSym.name + "'");
810 }
811 }
812 llvm::dbgs() << "Adding to stabsList: " << stab << "\n";
813 stabsList.push_back(stab);
814 }
815
816 file.setDebugInfo(llvm::make_unique<StabsDebugInfo>(std::move(stabsList)));
817
818 // FIXME: Kill this off when we fix YAML memory ownership.
819 file.debugInfo()->setAllocator(std::move(allocator));
820
821 return llvm::Error::success();
822}
823
824static llvm::DataExtractor
825dataExtractorFromSection(const NormalizedFile &normalizedFile,
826 const Section &S) {
827 const bool is64 = MachOLinkingContext::is64Bit(normalizedFile.arch);
828 const bool isBig = MachOLinkingContext::isBigEndian(normalizedFile.arch);
829 StringRef SecData(reinterpret_cast<const char*>(S.content.data()),
830 S.content.size());
831 return llvm::DataExtractor(SecData, !isBig, is64 ? 8 : 4);
832}
833
834// FIXME: Cribbed from llvm-dwp -- should share "lightweight CU DIE
835// inspection" code if possible.
836static uint32_t getCUAbbrevOffset(llvm::DataExtractor abbrevData,
837 uint64_t abbrCode) {
838 uint64_t curCode;
839 uint32_t offset = 0;
840 while ((curCode = abbrevData.getULEB128(&offset)) != abbrCode) {
841 // Tag
842 abbrevData.getULEB128(&offset);
843 // DW_CHILDREN
844 abbrevData.getU8(&offset);
845 // Attributes
846 while (abbrevData.getULEB128(&offset) | abbrevData.getULEB128(&offset))
847 ;
848 }
849 return offset;
850}
851
852// FIXME: Cribbed from llvm-dwp -- should share "lightweight CU DIE
853// inspection" code if possible.
854static Expected<const char *>
855getIndexedString(const NormalizedFile &normalizedFile,
856 llvm::dwarf::Form form, llvm::DataExtractor infoData,
857 uint32_t &infoOffset, const Section &stringsSection) {
858 if (form == llvm::dwarf::DW_FORM_string)
859 return infoData.getCStr(&infoOffset);
860 if (form != llvm::dwarf::DW_FORM_strp)
861 return llvm::make_error<GenericError>(
862 "string field encoded without DW_FORM_strp");
863 uint32_t stringOffset = infoData.getU32(&infoOffset);
864 llvm::DataExtractor stringsData =
865 dataExtractorFromSection(normalizedFile, stringsSection);
866 return stringsData.getCStr(&stringOffset);
867}
868
869// FIXME: Cribbed from llvm-dwp -- should share "lightweight CU DIE
870// inspection" code if possible.
871static llvm::Expected<TranslationUnitSource>
872readCompUnit(const NormalizedFile &normalizedFile,
873 const Section &info,
874 const Section &abbrev,
875 const Section &strings,
876 StringRef path) {
877 // FIXME: Cribbed from llvm-dwp -- should share "lightweight CU DIE
878 // inspection" code if possible.
879 uint32_t offset = 0;
880 llvm::dwarf::DwarfFormat Format = llvm::dwarf::DwarfFormat::DWARF32;
881 auto infoData = dataExtractorFromSection(normalizedFile, info);
882 uint32_t length = infoData.getU32(&offset);
883 if (length == 0xffffffff) {
884 Format = llvm::dwarf::DwarfFormat::DWARF64;
885 infoData.getU64(&offset);
886 }
887 else if (length > 0xffffff00)
888 return llvm::make_error<GenericError>("Malformed DWARF in " + path);
889
890 uint16_t version = infoData.getU16(&offset);
891
892 if (version < 2 || version > 4)
893 return llvm::make_error<GenericError>("Unsupported DWARF version in " +
894 path);
895
896 infoData.getU32(&offset); // Abbrev offset (should be zero)
897 uint8_t addrSize = infoData.getU8(&offset);
898
899 uint32_t abbrCode = infoData.getULEB128(&offset);
900 auto abbrevData = dataExtractorFromSection(normalizedFile, abbrev);
901 uint32_t abbrevOffset = getCUAbbrevOffset(abbrevData, abbrCode);
902 uint64_t tag = abbrevData.getULEB128(&abbrevOffset);
903 if (tag != llvm::dwarf::DW_TAG_compile_unit)
904 return llvm::make_error<GenericError>("top level DIE is not a compile unit");
905 // DW_CHILDREN
906 abbrevData.getU8(&abbrevOffset);
907 uint32_t name;
908 llvm::dwarf::Form form;
909 llvm::dwarf::FormParams formParams = {version, addrSize, Format};
910 TranslationUnitSource tu;
911 while ((name = abbrevData.getULEB128(&abbrevOffset)) |
912 (form = static_cast<llvm::dwarf::Form>(
913 abbrevData.getULEB128(&abbrevOffset))) &&
914 (name != 0 || form != 0)) {
915 switch (name) {
916 case llvm::dwarf::DW_AT_name: {
917 if (auto eName = getIndexedString(normalizedFile, form, infoData, offset,
918 strings))
919 tu.name = *eName;
920 else
921 return eName.takeError();
922 break;
923 }
924 case llvm::dwarf::DW_AT_comp_dir: {
925 if (auto eName = getIndexedString(normalizedFile, form, infoData, offset,
926 strings))
927 tu.path = *eName;
928 else
929 return eName.takeError();
930 break;
931 }
932 default:
933 llvm::DWARFFormValue::skipValue(form, infoData, &offset, formParams);
934 }
935 }
936 return tu;
937}
938
939llvm::Error parseDebugInfo(MachOFile &file,
940 const NormalizedFile &normalizedFile, bool copyRefs) {
941
942 // Find the interesting debug info sections.
943 const Section *debugInfo = nullptr;
944 const Section *debugAbbrev = nullptr;
945 const Section *debugStrings = nullptr;
946
947 for (auto &s : normalizedFile.sections) {
948 if (s.segmentName == "__DWARF") {
949 if (s.sectionName == "__debug_info")
950 debugInfo = &s;
951 else if (s.sectionName == "__debug_abbrev")
952 debugAbbrev = &s;
953 else if (s.sectionName == "__debug_str")
954 debugStrings = &s;
955 }
956 }
957
958 if (!debugInfo)
959 return parseStabs(file, normalizedFile, copyRefs);
960
961 if (debugInfo->content.size() == 0)
962 return llvm::Error::success();
963
964 if (debugInfo->content.size() < 12)
965 return llvm::make_error<GenericError>("Malformed __debug_info section in " +
966 file.path() + ": too small");
967
968 if (!debugAbbrev)
969 return llvm::make_error<GenericError>("Missing __dwarf_abbrev section in " +
970 file.path());
971
972 if (auto tuOrErr = readCompUnit(normalizedFile, *debugInfo, *debugAbbrev,
973 *debugStrings, file.path())) {
974 // FIXME: Kill of allocator and code under 'copyRefs' when we fix YAML
975 // memory ownership.
976 std::unique_ptr<BumpPtrAllocator> allocator;
977 if (copyRefs) {
978 allocator = llvm::make_unique<BumpPtrAllocator>();
979 tuOrErr->name = copyDebugString(tuOrErr->name, *allocator);
980 tuOrErr->path = copyDebugString(tuOrErr->path, *allocator);
981 }
982 file.setDebugInfo(llvm::make_unique<DwarfDebugInfo>(std::move(*tuOrErr)));
983 if (copyRefs)
984 file.debugInfo()->setAllocator(std::move(allocator));
985 } else
986 return tuOrErr.takeError();
987
988 return llvm::Error::success();
989}
990
991static int64_t readSPtr(bool is64, bool isBig, const uint8_t *addr) {
992 if (is64)
993 return read64(addr, isBig);
994
995 int32_t res = read32(addr, isBig);
996 return res;
997}
998
999/// --- Augmentation String Processing ---
1000
1001struct CIEInfo {
1002 bool _augmentationDataPresent = false;
1003 bool _mayHaveEH = false;
1004 uint32_t _offsetOfLSDA = ~0U;
1005 uint32_t _offsetOfPersonality = ~0U;
1006 uint32_t _offsetOfFDEPointerEncoding = ~0U;
1007 uint32_t _augmentationDataLength = ~0U;
1008};
1009
1010typedef llvm::DenseMap<const MachODefinedAtom*, CIEInfo> CIEInfoMap;
1011
1012static llvm::Error processAugmentationString(const uint8_t *augStr,
1013 CIEInfo &cieInfo,
1014 unsigned &len) {
1015
1016 if (augStr[0] == '\0') {
1017 len = 1;
1018 return llvm::Error::success();
1019 }
1020
1021 if (augStr[0] != 'z')
1022 return llvm::make_error<GenericError>("expected 'z' at start of "
1023 "augmentation string");
1024
1025 cieInfo._augmentationDataPresent = true;
1026 uint64_t idx = 1;
1027
1028 uint32_t offsetInAugmentationData = 0;
1029 while (augStr[idx] != '\0') {
1030 if (augStr[idx] == 'L') {
1031 cieInfo._offsetOfLSDA = offsetInAugmentationData;
1032 // This adds a single byte to the augmentation data.
1033 ++offsetInAugmentationData;
1034 ++idx;
1035 continue;
1036 }
1037 if (augStr[idx] == 'P') {
1038 cieInfo._offsetOfPersonality = offsetInAugmentationData;
1039 // This adds a single byte to the augmentation data for the encoding,
1040 // then a number of bytes for the pointer data.
1041 // FIXME: We are assuming 4 is correct here for the pointer size as we
1042 // always currently use delta32ToGOT.
1043 offsetInAugmentationData += 5;
1044 ++idx;
1045 continue;
1046 }
1047 if (augStr[idx] == 'R') {
1048 cieInfo._offsetOfFDEPointerEncoding = offsetInAugmentationData;
1049 // This adds a single byte to the augmentation data.
1050 ++offsetInAugmentationData;
1051 ++idx;
1052 continue;
1053 }
1054 if (augStr[idx] == 'e') {
1055 if (augStr[idx + 1] != 'h')
1056 return llvm::make_error<GenericError>("expected 'eh' in "
1057 "augmentation string");
1058 cieInfo._mayHaveEH = true;
1059 idx += 2;
1060 continue;
1061 }
1062 ++idx;
1063 }
1064
1065 cieInfo._augmentationDataLength = offsetInAugmentationData;
1066
1067 len = idx + 1;
1068 return llvm::Error::success();
1069}
1070
1071static llvm::Error processCIE(const NormalizedFile &normalizedFile,
1072 MachOFile &file,
1073 mach_o::ArchHandler &handler,
1074 const Section *ehFrameSection,
1075 MachODefinedAtom *atom,
1076 uint64_t offset,
1077 CIEInfoMap &cieInfos) {
1078 const bool isBig = MachOLinkingContext::isBigEndian(normalizedFile.arch);
1079 const uint8_t *frameData = atom->rawContent().data();
1080
1081 CIEInfo cieInfo;
1082
1083 uint32_t size = read32(frameData, isBig);
1084 uint64_t cieIDField = size == 0xffffffffU
5
Assuming 'size' is not equal to -1
6
'?' condition is false
1085 ? sizeof(uint32_t) + sizeof(uint64_t)
1086 : sizeof(uint32_t);
1087 uint64_t versionField = cieIDField + sizeof(uint32_t);
1088 uint64_t augmentationStringField = versionField + sizeof(uint8_t);
1089
1090 unsigned augmentationStringLength = 0;
1091 if (auto err = processAugmentationString(frameData + augmentationStringField,
7
Taking false branch
1092 cieInfo, augmentationStringLength))
1093 return err;
1094
1095 if (cieInfo._offsetOfPersonality != ~0U) {
8
Taking true branch
1096 // If we have augmentation data for the personality function, then we may
1097 // need to implicitly generate its relocation.
1098
1099 // Parse the EH Data field which is pointer sized.
1100 uint64_t EHDataField = augmentationStringField + augmentationStringLength;
1101 const bool is64 = MachOLinkingContext::is64Bit(normalizedFile.arch);
1102 unsigned EHDataFieldSize = (cieInfo._mayHaveEH ? (is64 ? 8 : 4) : 0);
9
'?' condition is false
1103
1104 // Parse Code Align Factor which is a ULEB128.
1105 uint64_t CodeAlignField = EHDataField + EHDataFieldSize;
1106 unsigned lengthFieldSize = 0;
1107 llvm::decodeULEB128(frameData + CodeAlignField, &lengthFieldSize);
1108
1109 // Parse Data Align Factor which is a SLEB128.
1110 uint64_t DataAlignField = CodeAlignField + lengthFieldSize;
1111 llvm::decodeSLEB128(frameData + DataAlignField, &lengthFieldSize);
1112
1113 // Parse Return Address Register which is a byte.
1114 uint64_t ReturnAddressField = DataAlignField + lengthFieldSize;
1115
1116 // Parse the augmentation length which is a ULEB128.
1117 uint64_t AugmentationLengthField = ReturnAddressField + 1;
1118 uint64_t AugmentationLength =
1119 llvm::decodeULEB128(frameData + AugmentationLengthField,
1120 &lengthFieldSize);
1121
1122 if (AugmentationLength != cieInfo._augmentationDataLength)
10
Assuming the condition is false
11
Taking false branch
1123 return llvm::make_error<GenericError>("CIE augmentation data length "
1124 "mismatch");
1125
1126 // Get the start address of the augmentation data.
1127 uint64_t AugmentationDataField = AugmentationLengthField + lengthFieldSize;
1128
1129 // Parse the personality function from the augmentation data.
1130 uint64_t PersonalityField =
1131 AugmentationDataField + cieInfo._offsetOfPersonality;
1132
1133 // Parse the personality encoding.
1134 // FIXME: Verify that this is a 32-bit pcrel offset.
1135 uint64_t PersonalityFunctionField = PersonalityField + 1;
1136
1137 if (atom->begin() != atom->end()) {
12
Taking false branch
1138 // If we have an explicit relocation, then make sure it matches this
1139 // offset as this is where we'd expect it to be applied to.
1140 DefinedAtom::reference_iterator CurrentRef = atom->begin();
1141 if (CurrentRef->offsetInAtom() != PersonalityFunctionField)
1142 return llvm::make_error<GenericError>("CIE personality reloc at "
1143 "wrong offset");
1144
1145 if (++CurrentRef != atom->end())
1146 return llvm::make_error<GenericError>("CIE contains too many relocs");
1147 } else {
1148 // Implicitly generate the personality function reloc. It's assumed to
1149 // be a delta32 offset to a GOT entry.
1150 // FIXME: Parse the encoding and check this.
1151 int32_t funcDelta = read32(frameData + PersonalityFunctionField, isBig);
1152 uint64_t funcAddress = ehFrameSection->address + offset +
1153 PersonalityFunctionField;
1154 funcAddress += funcDelta;
1155
1156 const MachODefinedAtom *func = nullptr;
1157 Reference::Addend addend;
13
'addend' declared without an initial value
1158 func = findAtomCoveringAddress(normalizedFile, file, funcAddress,
14
Calling 'findAtomCoveringAddress'
18
Returning from 'findAtomCoveringAddress'
1159 addend);
1160 atom->addReference(Reference::KindNamespace::mach_o, handler.kindArch(),
19
6th function call argument is an uninitialized value
1161 handler.unwindRefToPersonalityFunctionKind(),
1162 PersonalityFunctionField, func, addend);
1163 }
1164 } else if (atom->begin() != atom->end()) {
1165 // Otherwise, we expect there to be no relocations in this atom as the only
1166 // relocation would have been to the personality function.
1167 return llvm::make_error<GenericError>("unexpected relocation in CIE");
1168 }
1169
1170
1171 cieInfos[atom] = std::move(cieInfo);
1172
1173 return llvm::Error::success();
1174}
1175
1176static llvm::Error processFDE(const NormalizedFile &normalizedFile,
1177 MachOFile &file,
1178 mach_o::ArchHandler &handler,
1179 const Section *ehFrameSection,
1180 MachODefinedAtom *atom,
1181 uint64_t offset,
1182 const CIEInfoMap &cieInfos) {
1183
1184 const bool isBig = MachOLinkingContext::isBigEndian(normalizedFile.arch);
1185 const bool is64 = MachOLinkingContext::is64Bit(normalizedFile.arch);
1186
1187 // Compiler wasn't lazy and actually told us what it meant.
1188 // Unfortunately, the compiler may not have generated references for all of
1189 // [cie, func, lsda] and so we still need to parse the FDE and add references
1190 // for any the compiler didn't generate.
1191 if (atom->begin() != atom->end())
1192 atom->sortReferences();
1193
1194 DefinedAtom::reference_iterator CurrentRef = atom->begin();
1195
1196 // This helper returns the reference (if one exists) at the offset we are
1197 // currently processing. It automatically increments the ref iterator if we
1198 // do return a ref, and throws an error if we pass over a ref without
1199 // comsuming it.
1200 auto currentRefGetter = [&CurrentRef,
1201 &atom](uint64_t Offset)->const Reference* {
1202 // If there are no more refs found, then we are done.
1203 if (CurrentRef == atom->end())
1204 return nullptr;
1205
1206 const Reference *Ref = *CurrentRef;
1207
1208 // If we haven't reached the offset for this reference, then return that
1209 // we don't yet have a reference to process.
1210 if (Offset < Ref->offsetInAtom())
1211 return nullptr;
1212
1213 // If the offset is equal, then we want to process this ref.
1214 if (Offset == Ref->offsetInAtom()) {
1215 ++CurrentRef;
1216 return Ref;
1217 }
1218
1219 // The current ref is at an offset which is earlier than the current
1220 // offset, then we failed to consume it when we should have. In this case
1221 // throw an error.
1222 llvm::report_fatal_error("Skipped reference when processing FDE");
1223 };
1224
1225 // Helper to either get the reference at this current location, and verify
1226 // that it is of the expected type, or add a reference of that type.
1227 // Returns the reference target.
1228 auto verifyOrAddReference = [&](uint64_t targetAddress,
1229 Reference::KindValue refKind,
1230 uint64_t refAddress,
1231 bool allowsAddend)->const Atom* {
1232 if (auto *ref = currentRefGetter(refAddress)) {
1233 // The compiler already emitted a relocation for the CIE ref. This should
1234 // have been converted to the correct type of reference in
1235 // get[Pair]ReferenceInfo().
1236 assert(ref->kindValue() == refKind &&((ref->kindValue() == refKind && "Incorrect EHFrame reference kind"
) ? static_cast<void> (0) : __assert_fail ("ref->kindValue() == refKind && \"Incorrect EHFrame reference kind\""
, "/build/llvm-toolchain-snapshot-8~svn345461/tools/lld/lib/ReaderWriter/MachO/MachONormalizedFileToAtoms.cpp"
, 1237, __PRETTY_FUNCTION__))
1237 "Incorrect EHFrame reference kind")((ref->kindValue() == refKind && "Incorrect EHFrame reference kind"
) ? static_cast<void> (0) : __assert_fail ("ref->kindValue() == refKind && \"Incorrect EHFrame reference kind\""
, "/build/llvm-toolchain-snapshot-8~svn345461/tools/lld/lib/ReaderWriter/MachO/MachONormalizedFileToAtoms.cpp"
, 1237, __PRETTY_FUNCTION__))
;
1238 return ref->target();
1239 }
1240 Reference::Addend addend;
1241 auto *target = findAtomCoveringAddress(normalizedFile, file,
1242 targetAddress, addend);
1243 atom->addReference(Reference::KindNamespace::mach_o, handler.kindArch(),
1244 refKind, refAddress, target, addend);
1245
1246 if (!allowsAddend)
1247 assert(!addend && "EHFrame reference cannot have addend")((!addend && "EHFrame reference cannot have addend") ?
static_cast<void> (0) : __assert_fail ("!addend && \"EHFrame reference cannot have addend\""
, "/build/llvm-toolchain-snapshot-8~svn345461/tools/lld/lib/ReaderWriter/MachO/MachONormalizedFileToAtoms.cpp"
, 1247, __PRETTY_FUNCTION__))
;
1248 return target;
1249 };
1250
1251 const uint8_t *startFrameData = atom->rawContent().data();
1252 const uint8_t *frameData = startFrameData;
1253
1254 uint32_t size = read32(frameData, isBig);
1255 uint64_t cieFieldInFDE = size == 0xffffffffU
1256 ? sizeof(uint32_t) + sizeof(uint64_t)
1257 : sizeof(uint32_t);
1258
1259 // Linker needs to fixup a reference from the FDE to its parent CIE (a
1260 // 32-bit byte offset backwards in the __eh_frame section).
1261 uint32_t cieDelta = read32(frameData + cieFieldInFDE, isBig);
1262 uint64_t cieAddress = ehFrameSection->address + offset + cieFieldInFDE;
1263 cieAddress -= cieDelta;
1264
1265 auto *cieRefTarget = verifyOrAddReference(cieAddress,
1266 handler.unwindRefToCIEKind(),
1267 cieFieldInFDE, false);
1268 const MachODefinedAtom *cie = dyn_cast<MachODefinedAtom>(cieRefTarget);
1269 assert(cie && cie->contentType() == DefinedAtom::typeCFI &&((cie && cie->contentType() == DefinedAtom::typeCFI
&& "FDE's CIE field does not point at the start of a CIE."
) ? static_cast<void> (0) : __assert_fail ("cie && cie->contentType() == DefinedAtom::typeCFI && \"FDE's CIE field does not point at the start of a CIE.\""
, "/build/llvm-toolchain-snapshot-8~svn345461/tools/lld/lib/ReaderWriter/MachO/MachONormalizedFileToAtoms.cpp"
, 1270, __PRETTY_FUNCTION__))
1270 "FDE's CIE field does not point at the start of a CIE.")((cie && cie->contentType() == DefinedAtom::typeCFI
&& "FDE's CIE field does not point at the start of a CIE."
) ? static_cast<void> (0) : __assert_fail ("cie && cie->contentType() == DefinedAtom::typeCFI && \"FDE's CIE field does not point at the start of a CIE.\""
, "/build/llvm-toolchain-snapshot-8~svn345461/tools/lld/lib/ReaderWriter/MachO/MachONormalizedFileToAtoms.cpp"
, 1270, __PRETTY_FUNCTION__))
;
1271
1272 const CIEInfo &cieInfo = cieInfos.find(cie)->second;
1273
1274 // Linker needs to fixup reference from the FDE to the function it's
1275 // describing. FIXME: there are actually different ways to do this, and the
1276 // particular method used is specified in the CIE's augmentation fields
1277 // (hopefully)
1278 uint64_t rangeFieldInFDE = cieFieldInFDE + sizeof(uint32_t);
1279
1280 int64_t functionFromFDE = readSPtr(is64, isBig,
1281 frameData + rangeFieldInFDE);
1282 uint64_t rangeStart = ehFrameSection->address + offset + rangeFieldInFDE;
1283 rangeStart += functionFromFDE;
1284
1285 verifyOrAddReference(rangeStart,
1286 handler.unwindRefToFunctionKind(),
1287 rangeFieldInFDE, true);
1288
1289 // Handle the augmentation data if there is any.
1290 if (cieInfo._augmentationDataPresent) {
1291 // First process the augmentation data length field.
1292 uint64_t augmentationDataLengthFieldInFDE =
1293 rangeFieldInFDE + 2 * (is64 ? sizeof(uint64_t) : sizeof(uint32_t));
1294 unsigned lengthFieldSize = 0;
1295 uint64_t augmentationDataLength =
1296 llvm::decodeULEB128(frameData + augmentationDataLengthFieldInFDE,
1297 &lengthFieldSize);
1298
1299 if (cieInfo._offsetOfLSDA != ~0U && augmentationDataLength > 0) {
1300
1301 // Look at the augmentation data field.
1302 uint64_t augmentationDataFieldInFDE =
1303 augmentationDataLengthFieldInFDE + lengthFieldSize;
1304
1305 int64_t lsdaFromFDE = readSPtr(is64, isBig,
1306 frameData + augmentationDataFieldInFDE);
1307 uint64_t lsdaStart =
1308 ehFrameSection->address + offset + augmentationDataFieldInFDE +
1309 lsdaFromFDE;
1310
1311 verifyOrAddReference(lsdaStart,
1312 handler.unwindRefToFunctionKind(),
1313 augmentationDataFieldInFDE, true);
1314 }
1315 }
1316
1317 return llvm::Error::success();
1318}
1319
1320llvm::Error addEHFrameReferences(const NormalizedFile &normalizedFile,
1321 MachOFile &file,
1322 mach_o::ArchHandler &handler) {
1323
1324 const Section *ehFrameSection = nullptr;
1325 for (auto &section : normalizedFile.sections)
1326 if (section.segmentName == "__TEXT" &&
1327 section.sectionName == "__eh_frame") {
1328 ehFrameSection = &section;
1329 break;
1330 }
1331
1332 // No __eh_frame so nothing to do.
1333 if (!ehFrameSection)
1334 return llvm::Error::success();
1335
1336 llvm::Error ehFrameErr = llvm::Error::success();
1337 CIEInfoMap cieInfos;
1338
1339 file.eachAtomInSection(*ehFrameSection,
1340 [&](MachODefinedAtom *atom, uint64_t offset) -> void {
1341 assert(atom->contentType() == DefinedAtom::typeCFI)((atom->contentType() == DefinedAtom::typeCFI) ? static_cast
<void> (0) : __assert_fail ("atom->contentType() == DefinedAtom::typeCFI"
, "/build/llvm-toolchain-snapshot-8~svn345461/tools/lld/lib/ReaderWriter/MachO/MachONormalizedFileToAtoms.cpp"
, 1341, __PRETTY_FUNCTION__))
;
1342
1343 // Bail out if we've encountered an error.
1344 if (ehFrameErr)
1
Taking false branch
1345 return;
1346
1347 const bool isBig = MachOLinkingContext::isBigEndian(normalizedFile.arch);
1348 if (ArchHandler::isDwarfCIE(isBig, atom))
2
Assuming the condition is true
3
Taking true branch
1349 ehFrameErr = processCIE(normalizedFile, file, handler, ehFrameSection,
4
Calling 'processCIE'
1350 atom, offset, cieInfos);
1351 else
1352 ehFrameErr = processFDE(normalizedFile, file, handler, ehFrameSection,
1353 atom, offset, cieInfos);
1354 });
1355
1356 return ehFrameErr;
1357}
1358
1359llvm::Error parseObjCImageInfo(const Section &sect,
1360 const NormalizedFile &normalizedFile,
1361 MachOFile &file) {
1362
1363 // struct objc_image_info {
1364 // uint32_t version; // initially 0
1365 // uint32_t flags;
1366 // };
1367
1368 ArrayRef<uint8_t> content = sect.content;
1369 if (content.size() != 8)
1370 return llvm::make_error<GenericError>(sect.segmentName + "/" +
1371 sect.sectionName +
1372 " in file " + file.path() +
1373 " should be 8 bytes in size");
1374
1375 const bool isBig = MachOLinkingContext::isBigEndian(normalizedFile.arch);
1376 uint32_t version = read32(content.data(), isBig);
1377 if (version)
1378 return llvm::make_error<GenericError>(sect.segmentName + "/" +
1379 sect.sectionName +
1380 " in file " + file.path() +
1381 " should have version=0");
1382
1383 uint32_t flags = read32(content.data() + 4, isBig);
1384 if (flags & (MachOLinkingContext::objc_supports_gc |
1385 MachOLinkingContext::objc_gc_only))
1386 return llvm::make_error<GenericError>(sect.segmentName + "/" +
1387 sect.sectionName +
1388 " in file " + file.path() +
1389 " uses GC. This is not supported");
1390
1391 if (flags & MachOLinkingContext::objc_retainReleaseForSimulator)
1392 file.setObjcConstraint(MachOLinkingContext::objc_retainReleaseForSimulator);
1393 else
1394 file.setObjcConstraint(MachOLinkingContext::objc_retainRelease);
1395
1396 file.setSwiftVersion((flags >> 8) & 0xFF);
1397
1398 return llvm::Error::success();
1399}
1400
1401/// Converts normalized mach-o file into an lld::File and lld::Atoms.
1402llvm::Expected<std::unique_ptr<lld::File>>
1403objectToAtoms(const NormalizedFile &normalizedFile, StringRef path,
1404 bool copyRefs) {
1405 std::unique_ptr<MachOFile> file(new MachOFile(path));
1406 if (auto ec = normalizedObjectToAtoms(file.get(), normalizedFile, copyRefs))
1407 return std::move(ec);
1408 return std::unique_ptr<File>(std::move(file));
1409}
1410
1411llvm::Expected<std::unique_ptr<lld::File>>
1412dylibToAtoms(const NormalizedFile &normalizedFile, StringRef path,
1413 bool copyRefs) {
1414 // Instantiate SharedLibraryFile object.
1415 std::unique_ptr<MachODylibFile> file(new MachODylibFile(path));
1416 if (auto ec = normalizedDylibToAtoms(file.get(), normalizedFile, copyRefs))
1417 return std::move(ec);
1418 return std::unique_ptr<File>(std::move(file));
1419}
1420
1421} // anonymous namespace
1422
1423namespace normalized {
1424
1425static bool isObjCImageInfo(const Section &sect) {
1426 return (sect.segmentName == "__OBJC" && sect.sectionName == "__image_info") ||
1427 (sect.segmentName == "__DATA" && sect.sectionName == "__objc_imageinfo");
1428}
1429
1430llvm::Error
1431normalizedObjectToAtoms(MachOFile *file,
1432 const NormalizedFile &normalizedFile,
1433 bool copyRefs) {
1434 LLVM_DEBUG(llvm::dbgs() << "******** Normalizing file to atoms: "do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("normalized-file-to-atoms")) { llvm::dbgs() << "******** Normalizing file to atoms: "
<< file->path() << "\n"; } } while (false)
1435 << file->path() << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("normalized-file-to-atoms")) { llvm::dbgs() << "******** Normalizing file to atoms: "
<< file->path() << "\n"; } } while (false)
;
1436 bool scatterable = ((normalizedFile.flags & MH_SUBSECTIONS_VIA_SYMBOLS) != 0);
1437
1438 // Create atoms from each section.
1439 for (auto &sect : normalizedFile.sections) {
1440
1441 // If this is a debug-info section parse it specially.
1442 if (isDebugInfoSection(sect))
1443 continue;
1444
1445 // If the file contains an objc_image_info struct, then we should parse the
1446 // ObjC flags and Swift version.
1447 if (isObjCImageInfo(sect)) {
1448 if (auto ec = parseObjCImageInfo(sect, normalizedFile, *file))
1449 return ec;
1450 // We then skip adding atoms for this section as we use the ObjCPass to
1451 // re-emit this data after it has been aggregated for all files.
1452 continue;
1453 }
1454
1455 bool customSectionName;
1456 DefinedAtom::ContentType atomType = atomTypeFromSection(sect,
1457 customSectionName);
1458 if (auto ec = processSection(atomType, sect, customSectionName,
1459 normalizedFile, *file, scatterable, copyRefs))
1460 return ec;
1461 }
1462 // Create atoms from undefined symbols.
1463 for (auto &sym : normalizedFile.undefinedSymbols) {
1464 // Undefinded symbols with n_value != 0 are actually tentative definitions.
1465 if (sym.value == Hex64(0)) {
1466 file->addUndefinedAtom(sym.name, copyRefs);
1467 } else {
1468 file->addTentativeDefAtom(sym.name, atomScope(sym.scope), sym.value,
1469 DefinedAtom::Alignment(1 << (sym.desc >> 8)),
1470 copyRefs);
1471 }
1472 }
1473
1474 // Convert mach-o relocations to References
1475 std::unique_ptr<mach_o::ArchHandler> handler
1476 = ArchHandler::create(normalizedFile.arch);
1477 for (auto &sect : normalizedFile.sections) {
1478 if (isDebugInfoSection(sect))
1479 continue;
1480 if (llvm::Error ec = convertRelocs(sect, normalizedFile, scatterable,
1481 *file, *handler))
1482 return ec;
1483 }
1484
1485 // Add additional arch-specific References
1486 file->eachDefinedAtom([&](MachODefinedAtom* atom) -> void {
1487 handler->addAdditionalReferences(*atom);
1488 });
1489
1490 // Each __eh_frame section needs references to both __text (the function we're
1491 // providing unwind info for) and itself (FDE -> CIE). These aren't
1492 // represented in the relocations on some architectures, so we have to add
1493 // them back in manually there.
1494 if (auto ec = addEHFrameReferences(normalizedFile, *file, *handler))
1495 return ec;
1496
1497 // Process mach-o data-in-code regions array. That information is encoded in
1498 // atoms as References at each transition point.
1499 unsigned nextIndex = 0;
1500 for (const DataInCode &entry : normalizedFile.dataInCode) {
1501 ++nextIndex;
1502 const Section* s = findSectionCoveringAddress(normalizedFile, entry.offset);
1503 if (!s) {
1504 return llvm::make_error<GenericError>(Twine("LC_DATA_IN_CODE address ("
1505 + Twine(entry.offset)
1506 + ") is not in any section"));
1507 }
1508 uint64_t offsetInSect = entry.offset - s->address;
1509 uint32_t offsetInAtom;
1510 MachODefinedAtom *atom = file->findAtomCoveringAddress(*s, offsetInSect,
1511 &offsetInAtom);
1512 if (offsetInAtom + entry.length > atom->size()) {
1513 return llvm::make_error<GenericError>(Twine("LC_DATA_IN_CODE entry "
1514 "(offset="
1515 + Twine(entry.offset)
1516 + ", length="
1517 + Twine(entry.length)
1518 + ") crosses atom boundary."));
1519 }
1520 // Add reference that marks start of data-in-code.
1521 atom->addReference(Reference::KindNamespace::mach_o, handler->kindArch(),
1522 handler->dataInCodeTransitionStart(*atom),
1523 offsetInAtom, atom, entry.kind);
1524
1525 // Peek at next entry, if it starts where this one ends, skip ending ref.
1526 if (nextIndex < normalizedFile.dataInCode.size()) {
1527 const DataInCode &nextEntry = normalizedFile.dataInCode[nextIndex];
1528 if (nextEntry.offset == (entry.offset + entry.length))
1529 continue;
1530 }
1531
1532 // If data goes to end of function, skip ending ref.
1533 if ((offsetInAtom + entry.length) == atom->size())
1534 continue;
1535
1536 // Add reference that marks end of data-in-code.
1537 atom->addReference(Reference::KindNamespace::mach_o, handler->kindArch(),
1538 handler->dataInCodeTransitionEnd(*atom),
1539 offsetInAtom+entry.length, atom, 0);
1540 }
1541
1542 // Cache some attributes on the file for use later.
1543 file->setFlags(normalizedFile.flags);
1544 file->setArch(normalizedFile.arch);
1545 file->setOS(normalizedFile.os);
1546 file->setMinVersion(normalizedFile.minOSverson);
1547 file->setMinVersionLoadCommandKind(normalizedFile.minOSVersionKind);
1548
1549 // Sort references in each atom to their canonical order.
1550 for (const DefinedAtom* defAtom : file->defined()) {
1551 reinterpret_cast<const SimpleDefinedAtom*>(defAtom)->sortReferences();
1552 }
1553
1554 if (auto err = parseDebugInfo(*file, normalizedFile, copyRefs))
1555 return err;
1556
1557 return llvm::Error::success();
1558}
1559
1560llvm::Error
1561normalizedDylibToAtoms(MachODylibFile *file,
1562 const NormalizedFile &normalizedFile,
1563 bool copyRefs) {
1564 file->setInstallName(normalizedFile.installName);
1565 file->setCompatVersion(normalizedFile.compatVersion);
1566 file->setCurrentVersion(normalizedFile.currentVersion);
1567
1568 // Tell MachODylibFile object about all symbols it exports.
1569 if (!normalizedFile.exportInfo.empty()) {
1570 // If exports trie exists, use it instead of traditional symbol table.
1571 for (const Export &exp : normalizedFile.exportInfo) {
1572 bool weakDef = (exp.flags & EXPORT_SYMBOL_FLAGS_WEAK_DEFINITION);
1573 // StringRefs from export iterator are ephemeral, so force copy.
1574 file->addExportedSymbol(exp.name, weakDef, true);
1575 }
1576 } else {
1577 for (auto &sym : normalizedFile.globalSymbols) {
1578 assert((sym.scope & N_EXT) && "only expect external symbols here")(((sym.scope & N_EXT) && "only expect external symbols here"
) ? static_cast<void> (0) : __assert_fail ("(sym.scope & N_EXT) && \"only expect external symbols here\""
, "/build/llvm-toolchain-snapshot-8~svn345461/tools/lld/lib/ReaderWriter/MachO/MachONormalizedFileToAtoms.cpp"
, 1578, __PRETTY_FUNCTION__))
;
1579 bool weakDef = (sym.desc & N_WEAK_DEF);
1580 file->addExportedSymbol(sym.name, weakDef, copyRefs);
1581 }
1582 }
1583 // Tell MachODylibFile object about all dylibs it re-exports.
1584 for (const DependentDylib &dep : normalizedFile.dependentDylibs) {
1585 if (dep.kind == llvm::MachO::LC_REEXPORT_DYLIB)
1586 file->addReExportedDylib(dep.path);
1587 }
1588 return llvm::Error::success();
1589}
1590
1591void relocatableSectionInfoForContentType(DefinedAtom::ContentType atomType,
1592 StringRef &segmentName,
1593 StringRef &sectionName,
1594 SectionType &sectionType,
1595 SectionAttr &sectionAttrs,
1596 bool &relocsToDefinedCanBeImplicit) {
1597
1598 for (const MachORelocatableSectionToAtomType *p = sectsToAtomType ;
1599 p->atomType != DefinedAtom::typeUnknown; ++p) {
1600 if (p->atomType != atomType)
1601 continue;
1602 // Wild carded entries are ignored for reverse lookups.
1603 if (p->segmentName.empty() || p->sectionName.empty())
1604 continue;
1605 segmentName = p->segmentName;
1606 sectionName = p->sectionName;
1607 sectionType = p->sectionType;
1608 sectionAttrs = 0;
1609 relocsToDefinedCanBeImplicit = false;
1610 if (atomType == DefinedAtom::typeCode)
1611 sectionAttrs = S_ATTR_PURE_INSTRUCTIONS;
1612 if (atomType == DefinedAtom::typeCFI)
1613 relocsToDefinedCanBeImplicit = true;
1614 return;
1615 }
1616 llvm_unreachable("content type not yet supported")::llvm::llvm_unreachable_internal("content type not yet supported"
, "/build/llvm-toolchain-snapshot-8~svn345461/tools/lld/lib/ReaderWriter/MachO/MachONormalizedFileToAtoms.cpp"
, 1616)
;
1617}
1618
1619llvm::Expected<std::unique_ptr<lld::File>>
1620normalizedToAtoms(const NormalizedFile &normalizedFile, StringRef path,
1621 bool copyRefs) {
1622 switch (normalizedFile.fileType) {
1623 case MH_DYLIB:
1624 case MH_DYLIB_STUB:
1625 return dylibToAtoms(normalizedFile, path, copyRefs);
1626 case MH_OBJECT:
1627 return objectToAtoms(normalizedFile, path, copyRefs);
1628 default:
1629 llvm_unreachable("unhandled MachO file type!")::llvm::llvm_unreachable_internal("unhandled MachO file type!"
, "/build/llvm-toolchain-snapshot-8~svn345461/tools/lld/lib/ReaderWriter/MachO/MachONormalizedFileToAtoms.cpp"
, 1629)
;
1630 }
1631}
1632
1633} // namespace normalized
1634} // namespace mach_o
1635} // namespace lld