1 //===- DbiStreamBuilder.cpp - PDB Dbi Stream Creation -----------*- C++ -*-===//
2 //
3 //                     The LLVM Compiler Infrastructure
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 "llvm/DebugInfo/PDB/Native/DbiStreamBuilder.h"
11 
12 #include "llvm/ADT/ArrayRef.h"
13 #include "llvm/BinaryFormat/COFF.h"
14 #include "llvm/DebugInfo/CodeView/DebugFrameDataSubsection.h"
15 #include "llvm/DebugInfo/MSF/MSFBuilder.h"
16 #include "llvm/DebugInfo/MSF/MappedBlockStream.h"
17 #include "llvm/DebugInfo/PDB/Native/DbiModuleDescriptorBuilder.h"
18 #include "llvm/DebugInfo/PDB/Native/DbiStream.h"
19 #include "llvm/DebugInfo/PDB/Native/RawError.h"
20 #include "llvm/Object/COFF.h"
21 #include "llvm/Support/BinaryStreamWriter.h"
22 
23 using namespace llvm;
24 using namespace llvm::codeview;
25 using namespace llvm::msf;
26 using namespace llvm::pdb;
27 
DbiStreamBuilder(msf::MSFBuilder & Msf)28 DbiStreamBuilder::DbiStreamBuilder(msf::MSFBuilder &Msf)
29     : Msf(Msf), Allocator(Msf.getAllocator()), Age(1), BuildNumber(0),
30       PdbDllVersion(0), PdbDllRbld(0), Flags(0), MachineType(PDB_Machine::x86),
31       Header(nullptr) {}
32 
~DbiStreamBuilder()33 DbiStreamBuilder::~DbiStreamBuilder() {}
34 
setVersionHeader(PdbRaw_DbiVer V)35 void DbiStreamBuilder::setVersionHeader(PdbRaw_DbiVer V) { VerHeader = V; }
36 
setAge(uint32_t A)37 void DbiStreamBuilder::setAge(uint32_t A) { Age = A; }
38 
setBuildNumber(uint16_t B)39 void DbiStreamBuilder::setBuildNumber(uint16_t B) { BuildNumber = B; }
40 
setBuildNumber(uint8_t Major,uint8_t Minor)41 void DbiStreamBuilder::setBuildNumber(uint8_t Major, uint8_t Minor) {
42   BuildNumber = (uint16_t(Major) << DbiBuildNo::BuildMajorShift) &
43                 DbiBuildNo::BuildMajorMask;
44   BuildNumber |= (uint16_t(Minor) << DbiBuildNo::BuildMinorShift) &
45                  DbiBuildNo::BuildMinorMask;
46   BuildNumber |= DbiBuildNo::NewVersionFormatMask;
47 }
48 
setPdbDllVersion(uint16_t V)49 void DbiStreamBuilder::setPdbDllVersion(uint16_t V) { PdbDllVersion = V; }
50 
setPdbDllRbld(uint16_t R)51 void DbiStreamBuilder::setPdbDllRbld(uint16_t R) { PdbDllRbld = R; }
52 
setFlags(uint16_t F)53 void DbiStreamBuilder::setFlags(uint16_t F) { Flags = F; }
54 
setMachineType(PDB_Machine M)55 void DbiStreamBuilder::setMachineType(PDB_Machine M) { MachineType = M; }
56 
setMachineType(COFF::MachineTypes M)57 void DbiStreamBuilder::setMachineType(COFF::MachineTypes M) {
58   // These enums are mirrors of each other, so we can just cast the value.
59   MachineType = static_cast<pdb::PDB_Machine>(static_cast<unsigned>(M));
60 }
61 
setSectionMap(ArrayRef<SecMapEntry> SecMap)62 void DbiStreamBuilder::setSectionMap(ArrayRef<SecMapEntry> SecMap) {
63   SectionMap = SecMap;
64 }
65 
setGlobalsStreamIndex(uint32_t Index)66 void DbiStreamBuilder::setGlobalsStreamIndex(uint32_t Index) {
67   GlobalsStreamIndex = Index;
68 }
69 
setSymbolRecordStreamIndex(uint32_t Index)70 void DbiStreamBuilder::setSymbolRecordStreamIndex(uint32_t Index) {
71   SymRecordStreamIndex = Index;
72 }
73 
setPublicsStreamIndex(uint32_t Index)74 void DbiStreamBuilder::setPublicsStreamIndex(uint32_t Index) {
75   PublicsStreamIndex = Index;
76 }
77 
addNewFpoData(const codeview::FrameData & FD)78 void DbiStreamBuilder::addNewFpoData(const codeview::FrameData &FD) {
79   if (!NewFpoData.hasValue())
80     NewFpoData.emplace(false);
81 
82   NewFpoData->addFrameData(FD);
83 }
84 
addOldFpoData(const object::FpoData & FD)85 void DbiStreamBuilder::addOldFpoData(const object::FpoData &FD) {
86   OldFpoData.push_back(FD);
87 }
88 
addDbgStream(pdb::DbgHeaderType Type,ArrayRef<uint8_t> Data)89 Error DbiStreamBuilder::addDbgStream(pdb::DbgHeaderType Type,
90                                      ArrayRef<uint8_t> Data) {
91   assert(Type != DbgHeaderType::NewFPO &&
92          "NewFPO data should be written via addFrameData()!");
93 
94   DbgStreams[(int)Type].emplace();
95   DbgStreams[(int)Type]->Size = Data.size();
96   DbgStreams[(int)Type]->WriteFn = [Data](BinaryStreamWriter &Writer) {
97     return Writer.writeArray(Data);
98   };
99   return Error::success();
100 }
101 
addECName(StringRef Name)102 uint32_t DbiStreamBuilder::addECName(StringRef Name) {
103   return ECNamesBuilder.insert(Name);
104 }
105 
calculateSerializedLength() const106 uint32_t DbiStreamBuilder::calculateSerializedLength() const {
107   // For now we only support serializing the header.
108   return sizeof(DbiStreamHeader) + calculateFileInfoSubstreamSize() +
109          calculateModiSubstreamSize() + calculateSectionContribsStreamSize() +
110          calculateSectionMapStreamSize() + calculateDbgStreamsSize() +
111          ECNamesBuilder.calculateSerializedSize();
112 }
113 
114 Expected<DbiModuleDescriptorBuilder &>
addModuleInfo(StringRef ModuleName)115 DbiStreamBuilder::addModuleInfo(StringRef ModuleName) {
116   uint32_t Index = ModiList.size();
117   ModiList.push_back(
118       llvm::make_unique<DbiModuleDescriptorBuilder>(ModuleName, Index, Msf));
119   return *ModiList.back();
120 }
121 
addModuleSourceFile(DbiModuleDescriptorBuilder & Module,StringRef File)122 Error DbiStreamBuilder::addModuleSourceFile(DbiModuleDescriptorBuilder &Module,
123                                             StringRef File) {
124   uint32_t Index = SourceFileNames.size();
125   SourceFileNames.insert(std::make_pair(File, Index));
126   Module.addSourceFile(File);
127   return Error::success();
128 }
129 
getSourceFileNameIndex(StringRef File)130 Expected<uint32_t> DbiStreamBuilder::getSourceFileNameIndex(StringRef File) {
131   auto NameIter = SourceFileNames.find(File);
132   if (NameIter == SourceFileNames.end())
133     return make_error<RawError>(raw_error_code::no_entry,
134                                 "The specified source file was not found");
135   return NameIter->getValue();
136 }
137 
calculateModiSubstreamSize() const138 uint32_t DbiStreamBuilder::calculateModiSubstreamSize() const {
139   uint32_t Size = 0;
140   for (const auto &M : ModiList)
141     Size += M->calculateSerializedLength();
142   return Size;
143 }
144 
calculateSectionContribsStreamSize() const145 uint32_t DbiStreamBuilder::calculateSectionContribsStreamSize() const {
146   if (SectionContribs.empty())
147     return 0;
148   return sizeof(enum PdbRaw_DbiSecContribVer) +
149          sizeof(SectionContribs[0]) * SectionContribs.size();
150 }
151 
calculateSectionMapStreamSize() const152 uint32_t DbiStreamBuilder::calculateSectionMapStreamSize() const {
153   if (SectionMap.empty())
154     return 0;
155   return sizeof(SecMapHeader) + sizeof(SecMapEntry) * SectionMap.size();
156 }
157 
calculateNamesOffset() const158 uint32_t DbiStreamBuilder::calculateNamesOffset() const {
159   uint32_t Offset = 0;
160   Offset += sizeof(ulittle16_t);                         // NumModules
161   Offset += sizeof(ulittle16_t);                         // NumSourceFiles
162   Offset += ModiList.size() * sizeof(ulittle16_t);       // ModIndices
163   Offset += ModiList.size() * sizeof(ulittle16_t);       // ModFileCounts
164   uint32_t NumFileInfos = 0;
165   for (const auto &M : ModiList)
166     NumFileInfos += M->source_files().size();
167   Offset += NumFileInfos * sizeof(ulittle32_t); // FileNameOffsets
168   return Offset;
169 }
170 
calculateFileInfoSubstreamSize() const171 uint32_t DbiStreamBuilder::calculateFileInfoSubstreamSize() const {
172   uint32_t Size = calculateNamesOffset();
173   Size += calculateNamesBufferSize();
174   return alignTo(Size, sizeof(uint32_t));
175 }
176 
calculateNamesBufferSize() const177 uint32_t DbiStreamBuilder::calculateNamesBufferSize() const {
178   uint32_t Size = 0;
179   for (const auto &F : SourceFileNames) {
180     Size += F.getKeyLength() + 1; // Names[I];
181   }
182   return Size;
183 }
184 
calculateDbgStreamsSize() const185 uint32_t DbiStreamBuilder::calculateDbgStreamsSize() const {
186   return DbgStreams.size() * sizeof(uint16_t);
187 }
188 
generateFileInfoSubstream()189 Error DbiStreamBuilder::generateFileInfoSubstream() {
190   uint32_t Size = calculateFileInfoSubstreamSize();
191   auto Data = Allocator.Allocate<uint8_t>(Size);
192   uint32_t NamesOffset = calculateNamesOffset();
193 
194   FileInfoBuffer = MutableBinaryByteStream(MutableArrayRef<uint8_t>(Data, Size),
195                                            llvm::support::little);
196 
197   WritableBinaryStreamRef MetadataBuffer =
198       WritableBinaryStreamRef(FileInfoBuffer).keep_front(NamesOffset);
199   BinaryStreamWriter MetadataWriter(MetadataBuffer);
200 
201   uint16_t ModiCount = std::min<uint32_t>(UINT16_MAX, ModiList.size());
202   uint16_t FileCount = std::min<uint32_t>(UINT16_MAX, SourceFileNames.size());
203   if (auto EC = MetadataWriter.writeInteger(ModiCount)) // NumModules
204     return EC;
205   if (auto EC = MetadataWriter.writeInteger(FileCount)) // NumSourceFiles
206     return EC;
207   for (uint16_t I = 0; I < ModiCount; ++I) {
208     if (auto EC = MetadataWriter.writeInteger(I)) // Mod Indices
209       return EC;
210   }
211   for (const auto &MI : ModiList) {
212     FileCount = static_cast<uint16_t>(MI->source_files().size());
213     if (auto EC = MetadataWriter.writeInteger(FileCount)) // Mod File Counts
214       return EC;
215   }
216 
217   // Before writing the FileNameOffsets array, write the NamesBuffer array.
218   // A side effect of this is that this will actually compute the various
219   // file name offsets, so we can then go back and write the FileNameOffsets
220   // array to the other substream.
221   NamesBuffer = WritableBinaryStreamRef(FileInfoBuffer).drop_front(NamesOffset);
222   BinaryStreamWriter NameBufferWriter(NamesBuffer);
223   for (auto &Name : SourceFileNames) {
224     Name.second = NameBufferWriter.getOffset();
225     if (auto EC = NameBufferWriter.writeCString(Name.getKey()))
226       return EC;
227   }
228 
229   for (const auto &MI : ModiList) {
230     for (StringRef Name : MI->source_files()) {
231       auto Result = SourceFileNames.find(Name);
232       if (Result == SourceFileNames.end())
233         return make_error<RawError>(raw_error_code::no_entry,
234                                     "The source file was not found.");
235       if (auto EC = MetadataWriter.writeInteger(Result->second))
236         return EC;
237     }
238   }
239 
240   if (auto EC = NameBufferWriter.padToAlignment(sizeof(uint32_t)))
241     return EC;
242 
243   if (NameBufferWriter.bytesRemaining() > 0)
244     return make_error<RawError>(raw_error_code::invalid_format,
245                                 "The names buffer contained unexpected data.");
246 
247   if (MetadataWriter.bytesRemaining() > sizeof(uint32_t))
248     return make_error<RawError>(
249         raw_error_code::invalid_format,
250         "The metadata buffer contained unexpected data.");
251 
252   return Error::success();
253 }
254 
finalize()255 Error DbiStreamBuilder::finalize() {
256   if (Header)
257     return Error::success();
258 
259   for (auto &MI : ModiList)
260     MI->finalize();
261 
262   if (auto EC = generateFileInfoSubstream())
263     return EC;
264 
265   DbiStreamHeader *H = Allocator.Allocate<DbiStreamHeader>();
266   ::memset(H, 0, sizeof(DbiStreamHeader));
267   H->VersionHeader = *VerHeader;
268   H->VersionSignature = -1;
269   H->Age = Age;
270   H->BuildNumber = BuildNumber;
271   H->Flags = Flags;
272   H->PdbDllRbld = PdbDllRbld;
273   H->PdbDllVersion = PdbDllVersion;
274   H->MachineType = static_cast<uint16_t>(MachineType);
275 
276   H->ECSubstreamSize = ECNamesBuilder.calculateSerializedSize();
277   H->FileInfoSize = FileInfoBuffer.getLength();
278   H->ModiSubstreamSize = calculateModiSubstreamSize();
279   H->OptionalDbgHdrSize = DbgStreams.size() * sizeof(uint16_t);
280   H->SecContrSubstreamSize = calculateSectionContribsStreamSize();
281   H->SectionMapSize = calculateSectionMapStreamSize();
282   H->TypeServerSize = 0;
283   H->SymRecordStreamIndex = SymRecordStreamIndex;
284   H->PublicSymbolStreamIndex = PublicsStreamIndex;
285   H->MFCTypeServerIndex = 0; // Not sure what this is, but link.exe writes 0.
286   H->GlobalSymbolStreamIndex = GlobalsStreamIndex;
287 
288   Header = H;
289   return Error::success();
290 }
291 
finalizeMsfLayout()292 Error DbiStreamBuilder::finalizeMsfLayout() {
293   if (NewFpoData.hasValue()) {
294     DbgStreams[(int)DbgHeaderType::NewFPO].emplace();
295     DbgStreams[(int)DbgHeaderType::NewFPO]->Size =
296         NewFpoData->calculateSerializedSize();
297     DbgStreams[(int)DbgHeaderType::NewFPO]->WriteFn =
298         [this](BinaryStreamWriter &Writer) {
299           return NewFpoData->commit(Writer);
300         };
301   }
302 
303   if (!OldFpoData.empty()) {
304     DbgStreams[(int)DbgHeaderType::FPO].emplace();
305     DbgStreams[(int)DbgHeaderType::FPO]->Size =
306         sizeof(object::FpoData) * OldFpoData.size();
307     DbgStreams[(int)DbgHeaderType::FPO]->WriteFn =
308         [this](BinaryStreamWriter &Writer) {
309           return Writer.writeArray(makeArrayRef(OldFpoData));
310         };
311   }
312 
313   for (auto &S : DbgStreams) {
314     if (!S.hasValue())
315       continue;
316     auto ExpectedIndex = Msf.addStream(S->Size);
317     if (!ExpectedIndex)
318       return ExpectedIndex.takeError();
319     S->StreamNumber = *ExpectedIndex;
320   }
321 
322   for (auto &MI : ModiList) {
323     if (auto EC = MI->finalizeMsfLayout())
324       return EC;
325   }
326 
327   uint32_t Length = calculateSerializedLength();
328   if (auto EC = Msf.setStreamSize(StreamDBI, Length))
329     return EC;
330   return Error::success();
331 }
332 
toSecMapFlags(uint32_t Flags)333 static uint16_t toSecMapFlags(uint32_t Flags) {
334   uint16_t Ret = 0;
335   if (Flags & COFF::IMAGE_SCN_MEM_READ)
336     Ret |= static_cast<uint16_t>(OMFSegDescFlags::Read);
337   if (Flags & COFF::IMAGE_SCN_MEM_WRITE)
338     Ret |= static_cast<uint16_t>(OMFSegDescFlags::Write);
339   if (Flags & COFF::IMAGE_SCN_MEM_EXECUTE)
340     Ret |= static_cast<uint16_t>(OMFSegDescFlags::Execute);
341   if (Flags & COFF::IMAGE_SCN_MEM_EXECUTE)
342     Ret |= static_cast<uint16_t>(OMFSegDescFlags::Execute);
343   if (!(Flags & COFF::IMAGE_SCN_MEM_16BIT))
344     Ret |= static_cast<uint16_t>(OMFSegDescFlags::AddressIs32Bit);
345 
346   // This seems always 1.
347   Ret |= static_cast<uint16_t>(OMFSegDescFlags::IsSelector);
348 
349   return Ret;
350 }
351 
352 // A utility function to create a Section Map for a given list of COFF sections.
353 //
354 // A Section Map seem to be a copy of a COFF section list in other format.
355 // I don't know why a PDB file contains both a COFF section header and
356 // a Section Map, but it seems it must be present in a PDB.
createSectionMap(ArrayRef<llvm::object::coff_section> SecHdrs)357 std::vector<SecMapEntry> DbiStreamBuilder::createSectionMap(
358     ArrayRef<llvm::object::coff_section> SecHdrs) {
359   std::vector<SecMapEntry> Ret;
360   int Idx = 0;
361 
362   auto Add = [&]() -> SecMapEntry & {
363     Ret.emplace_back();
364     auto &Entry = Ret.back();
365     memset(&Entry, 0, sizeof(Entry));
366 
367     Entry.Frame = Idx + 1;
368 
369     // We don't know the meaning of these fields yet.
370     Entry.SecName = UINT16_MAX;
371     Entry.ClassName = UINT16_MAX;
372 
373     return Entry;
374   };
375 
376   for (auto &Hdr : SecHdrs) {
377     auto &Entry = Add();
378     Entry.Flags = toSecMapFlags(Hdr.Characteristics);
379     Entry.SecByteLength = Hdr.VirtualSize;
380     ++Idx;
381   }
382 
383   // The last entry is for absolute symbols.
384   auto &Entry = Add();
385   Entry.Flags = static_cast<uint16_t>(OMFSegDescFlags::AddressIs32Bit) |
386                 static_cast<uint16_t>(OMFSegDescFlags::IsAbsoluteAddress);
387   Entry.SecByteLength = UINT32_MAX;
388 
389   return Ret;
390 }
391 
commit(const msf::MSFLayout & Layout,WritableBinaryStreamRef MsfBuffer)392 Error DbiStreamBuilder::commit(const msf::MSFLayout &Layout,
393                                WritableBinaryStreamRef MsfBuffer) {
394   if (auto EC = finalize())
395     return EC;
396 
397   auto DbiS = WritableMappedBlockStream::createIndexedStream(
398       Layout, MsfBuffer, StreamDBI, Allocator);
399 
400   BinaryStreamWriter Writer(*DbiS);
401   if (auto EC = Writer.writeObject(*Header))
402     return EC;
403 
404   for (auto &M : ModiList) {
405     if (auto EC = M->commit(Writer, Layout, MsfBuffer))
406       return EC;
407   }
408 
409   if (!SectionContribs.empty()) {
410     if (auto EC = Writer.writeEnum(DbiSecContribVer60))
411       return EC;
412     if (auto EC = Writer.writeArray(makeArrayRef(SectionContribs)))
413       return EC;
414   }
415 
416   if (!SectionMap.empty()) {
417     ulittle16_t Size = static_cast<ulittle16_t>(SectionMap.size());
418     SecMapHeader SMHeader = {Size, Size};
419     if (auto EC = Writer.writeObject(SMHeader))
420       return EC;
421     if (auto EC = Writer.writeArray(SectionMap))
422       return EC;
423   }
424 
425   if (auto EC = Writer.writeStreamRef(FileInfoBuffer))
426     return EC;
427 
428   if (auto EC = ECNamesBuilder.commit(Writer))
429     return EC;
430 
431   for (auto &Stream : DbgStreams) {
432     uint16_t StreamNumber = kInvalidStreamIndex;
433     if (Stream.hasValue())
434       StreamNumber = Stream->StreamNumber;
435     if (auto EC = Writer.writeInteger(StreamNumber))
436       return EC;
437   }
438 
439   for (auto &Stream : DbgStreams) {
440     if (!Stream.hasValue())
441       continue;
442     assert(Stream->StreamNumber != kInvalidStreamIndex);
443 
444     auto WritableStream = WritableMappedBlockStream::createIndexedStream(
445         Layout, MsfBuffer, Stream->StreamNumber, Allocator);
446     BinaryStreamWriter DbgStreamWriter(*WritableStream);
447 
448     if (auto EC = Stream->WriteFn(DbgStreamWriter))
449       return EC;
450   }
451 
452   if (Writer.bytesRemaining() > 0)
453     return make_error<RawError>(raw_error_code::invalid_format,
454                                 "Unexpected bytes found in DBI Stream");
455   return Error::success();
456 }
457