1 //===- tools/dsymutil/DebugMap.cpp - Generic debug map representation -----===//
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 #include "DebugMap.h"
11 #include "BinaryHolder.h"
12 #include "llvm/ADT/Optional.h"
13 #include "llvm/ADT/SmallString.h"
14 #include "llvm/ADT/StringMap.h"
15 #include "llvm/ADT/StringRef.h"
16 #include "llvm/ADT/Triple.h"
17 #include "llvm/ADT/iterator_range.h"
18 #include "llvm/BinaryFormat/MachO.h"
19 #include "llvm/Object/ObjectFile.h"
20 #include "llvm/Support/Chrono.h"
21 #include "llvm/Support/Error.h"
22 #include "llvm/Support/Format.h"
23 #include "llvm/Support/MemoryBuffer.h"
24 #include "llvm/Support/Path.h"
25 #include "llvm/Support/YAMLTraits.h"
26 #include "llvm/Support/raw_ostream.h"
27 #include <algorithm>
28 #include <cinttypes>
29 #include <cstdint>
30 #include <memory>
31 #include <string>
32 #include <utility>
33 #include <vector>
34 
35 namespace llvm {
36 
37 namespace dsymutil {
38 
39 using namespace llvm::object;
40 
41 DebugMapObject::DebugMapObject(StringRef ObjectFilename,
42                                sys::TimePoint<std::chrono::seconds> Timestamp,
43                                uint8_t Type)
44     : Filename(ObjectFilename), Timestamp(Timestamp), Type(Type) {}
45 
46 bool DebugMapObject::addSymbol(StringRef Name, Optional<uint64_t> ObjectAddress,
47                                uint64_t LinkedAddress, uint32_t Size) {
48   auto InsertResult = Symbols.insert(
49       std::make_pair(Name, SymbolMapping(ObjectAddress, LinkedAddress, Size)));
50 
51   if (ObjectAddress && InsertResult.second)
52     AddressToMapping[*ObjectAddress] = &*InsertResult.first;
53   return InsertResult.second;
54 }
55 
56 void DebugMapObject::print(raw_ostream &OS) const {
57   OS << getObjectFilename() << ":\n";
58   // Sort the symbols in alphabetical order, like llvm-nm (and to get
59   // deterministic output for testing).
60   using Entry = std::pair<StringRef, SymbolMapping>;
61   std::vector<Entry> Entries;
62   Entries.reserve(Symbols.getNumItems());
63   for (const auto &Sym : make_range(Symbols.begin(), Symbols.end()))
64     Entries.push_back(std::make_pair(Sym.getKey(), Sym.getValue()));
65   std::sort(
66       Entries.begin(), Entries.end(),
67       [](const Entry &LHS, const Entry &RHS) { return LHS.first < RHS.first; });
68   for (const auto &Sym : Entries) {
69     if (Sym.second.ObjectAddress)
70       OS << format("\t%016" PRIx64, uint64_t(*Sym.second.ObjectAddress));
71     else
72       OS << "\t????????????????";
73     OS << format(" => %016" PRIx64 "+0x%x\t%s\n",
74                  uint64_t(Sym.second.BinaryAddress), uint32_t(Sym.second.Size),
75                  Sym.first.data());
76   }
77   OS << '\n';
78 }
79 
80 #ifndef NDEBUG
81 void DebugMapObject::dump() const { print(errs()); }
82 #endif
83 
84 DebugMapObject &
85 DebugMap::addDebugMapObject(StringRef ObjectFilePath,
86                             sys::TimePoint<std::chrono::seconds> Timestamp,
87                             uint8_t Type) {
88   Objects.emplace_back(new DebugMapObject(ObjectFilePath, Timestamp, Type));
89   return *Objects.back();
90 }
91 
92 const DebugMapObject::DebugMapEntry *
93 DebugMapObject::lookupSymbol(StringRef SymbolName) const {
94   StringMap<SymbolMapping>::const_iterator Sym = Symbols.find(SymbolName);
95   if (Sym == Symbols.end())
96     return nullptr;
97   return &*Sym;
98 }
99 
100 const DebugMapObject::DebugMapEntry *
101 DebugMapObject::lookupObjectAddress(uint64_t Address) const {
102   auto Mapping = AddressToMapping.find(Address);
103   if (Mapping == AddressToMapping.end())
104     return nullptr;
105   return Mapping->getSecond();
106 }
107 
108 void DebugMap::print(raw_ostream &OS) const {
109   yaml::Output yout(OS, /* Ctxt = */ nullptr, /* WrapColumn = */ 0);
110   yout << const_cast<DebugMap &>(*this);
111 }
112 
113 #ifndef NDEBUG
114 void DebugMap::dump() const { print(errs()); }
115 #endif
116 
117 namespace {
118 
119 struct YAMLContext {
120   StringRef PrependPath;
121   Triple BinaryTriple;
122 };
123 
124 } // end anonymous namespace
125 
126 ErrorOr<std::vector<std::unique_ptr<DebugMap>>>
127 DebugMap::parseYAMLDebugMap(StringRef InputFile, StringRef PrependPath,
128                             bool Verbose) {
129   auto ErrOrFile = MemoryBuffer::getFileOrSTDIN(InputFile);
130   if (auto Err = ErrOrFile.getError())
131     return Err;
132 
133   YAMLContext Ctxt;
134 
135   Ctxt.PrependPath = PrependPath;
136 
137   std::unique_ptr<DebugMap> Res;
138   yaml::Input yin((*ErrOrFile)->getBuffer(), &Ctxt);
139   yin >> Res;
140 
141   if (auto EC = yin.error())
142     return EC;
143   std::vector<std::unique_ptr<DebugMap>> Result;
144   Result.push_back(std::move(Res));
145   return std::move(Result);
146 }
147 
148 } // end namespace dsymutil
149 
150 namespace yaml {
151 
152 // Normalize/Denormalize between YAML and a DebugMapObject.
153 struct MappingTraits<dsymutil::DebugMapObject>::YamlDMO {
154   YamlDMO(IO &io) { Timestamp = 0; }
155   YamlDMO(IO &io, dsymutil::DebugMapObject &Obj);
156   dsymutil::DebugMapObject denormalize(IO &IO);
157 
158   std::string Filename;
159   int64_t Timestamp;
160   std::vector<dsymutil::DebugMapObject::YAMLSymbolMapping> Entries;
161 };
162 
163 void MappingTraits<std::pair<std::string, DebugMapObject::SymbolMapping>>::
164     mapping(IO &io, std::pair<std::string, DebugMapObject::SymbolMapping> &s) {
165   io.mapRequired("sym", s.first);
166   io.mapOptional("objAddr", s.second.ObjectAddress);
167   io.mapRequired("binAddr", s.second.BinaryAddress);
168   io.mapOptional("size", s.second.Size);
169 }
170 
171 void MappingTraits<dsymutil::DebugMapObject>::mapping(
172     IO &io, dsymutil::DebugMapObject &DMO) {
173   MappingNormalization<YamlDMO, dsymutil::DebugMapObject> Norm(io, DMO);
174   io.mapRequired("filename", Norm->Filename);
175   io.mapOptional("timestamp", Norm->Timestamp);
176   io.mapRequired("symbols", Norm->Entries);
177 }
178 
179 void ScalarTraits<Triple>::output(const Triple &val, void *, raw_ostream &out) {
180   out << val.str();
181 }
182 
183 StringRef ScalarTraits<Triple>::input(StringRef scalar, void *, Triple &value) {
184   value = Triple(scalar);
185   return StringRef();
186 }
187 
188 size_t
189 SequenceTraits<std::vector<std::unique_ptr<dsymutil::DebugMapObject>>>::size(
190     IO &io, std::vector<std::unique_ptr<dsymutil::DebugMapObject>> &seq) {
191   return seq.size();
192 }
193 
194 dsymutil::DebugMapObject &
195 SequenceTraits<std::vector<std::unique_ptr<dsymutil::DebugMapObject>>>::element(
196     IO &, std::vector<std::unique_ptr<dsymutil::DebugMapObject>> &seq,
197     size_t index) {
198   if (index >= seq.size()) {
199     seq.resize(index + 1);
200     seq[index].reset(new dsymutil::DebugMapObject);
201   }
202   return *seq[index];
203 }
204 
205 void MappingTraits<dsymutil::DebugMap>::mapping(IO &io,
206                                                 dsymutil::DebugMap &DM) {
207   io.mapRequired("triple", DM.BinaryTriple);
208   io.mapOptional("binary-path", DM.BinaryPath);
209   if (void *Ctxt = io.getContext())
210     reinterpret_cast<YAMLContext *>(Ctxt)->BinaryTriple = DM.BinaryTriple;
211   io.mapOptional("objects", DM.Objects);
212 }
213 
214 void MappingTraits<std::unique_ptr<dsymutil::DebugMap>>::mapping(
215     IO &io, std::unique_ptr<dsymutil::DebugMap> &DM) {
216   if (!DM)
217     DM.reset(new DebugMap());
218   io.mapRequired("triple", DM->BinaryTriple);
219   io.mapOptional("binary-path", DM->BinaryPath);
220   if (void *Ctxt = io.getContext())
221     reinterpret_cast<YAMLContext *>(Ctxt)->BinaryTriple = DM->BinaryTriple;
222   io.mapOptional("objects", DM->Objects);
223 }
224 
225 MappingTraits<dsymutil::DebugMapObject>::YamlDMO::YamlDMO(
226     IO &io, dsymutil::DebugMapObject &Obj) {
227   Filename = Obj.Filename;
228   Timestamp = sys::toTimeT(Obj.getTimestamp());
229   Entries.reserve(Obj.Symbols.size());
230   for (auto &Entry : Obj.Symbols)
231     Entries.push_back(std::make_pair(Entry.getKey(), Entry.getValue()));
232 }
233 
234 dsymutil::DebugMapObject
235 MappingTraits<dsymutil::DebugMapObject>::YamlDMO::denormalize(IO &IO) {
236   BinaryHolder BinHolder(/* Verbose =*/false);
237   const auto &Ctxt = *reinterpret_cast<YAMLContext *>(IO.getContext());
238   SmallString<80> Path(Ctxt.PrependPath);
239   StringMap<uint64_t> SymbolAddresses;
240 
241   sys::path::append(Path, Filename);
242   auto ErrOrObjectFiles = BinHolder.GetObjectFiles(Path);
243   if (auto EC = ErrOrObjectFiles.getError()) {
244     errs() << "warning: Unable to open " << Path << " " << EC.message() << '\n';
245   } else if (auto ErrOrObjectFile = BinHolder.Get(Ctxt.BinaryTriple)) {
246     // Rewrite the object file symbol addresses in the debug map. The
247     // YAML input is mainly used to test llvm-dsymutil without
248     // requiring binaries checked-in. If we generate the object files
249     // during the test, we can't hardcode the symbols addresses, so
250     // look them up here and rewrite them.
251     for (const auto &Sym : ErrOrObjectFile->symbols()) {
252       uint64_t Address = Sym.getValue();
253       Expected<StringRef> Name = Sym.getName();
254       if (!Name ||
255           (Sym.getFlags() & (SymbolRef::SF_Absolute | SymbolRef::SF_Common))) {
256         // TODO: Actually report errors helpfully.
257         if (!Name)
258           consumeError(Name.takeError());
259         continue;
260       }
261       SymbolAddresses[*Name] = Address;
262     }
263   }
264 
265   dsymutil::DebugMapObject Res(Path, sys::toTimePoint(Timestamp), MachO::N_OSO);
266   for (auto &Entry : Entries) {
267     auto &Mapping = Entry.second;
268     Optional<uint64_t> ObjAddress;
269     if (Mapping.ObjectAddress)
270       ObjAddress = *Mapping.ObjectAddress;
271     auto AddressIt = SymbolAddresses.find(Entry.first);
272     if (AddressIt != SymbolAddresses.end())
273       ObjAddress = AddressIt->getValue();
274     Res.addSymbol(Entry.first, ObjAddress, Mapping.BinaryAddress, Mapping.Size);
275   }
276   return Res;
277 }
278 
279 } // end namespace yaml
280 
281 } // end namespace llvm
282