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