1 //===- TpiStream.cpp - PDB Type Info (TPI) Stream 2 Access ----------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 #include "llvm/DebugInfo/PDB/Native/TpiStream.h"
10 
11 #include "llvm/ADT/iterator_range.h"
12 #include "llvm/DebugInfo/CodeView/LazyRandomTypeCollection.h"
13 #include "llvm/DebugInfo/CodeView/RecordName.h"
14 #include "llvm/DebugInfo/CodeView/TypeRecord.h"
15 #include "llvm/DebugInfo/CodeView/TypeRecordHelpers.h"
16 #include "llvm/DebugInfo/MSF/MappedBlockStream.h"
17 #include "llvm/DebugInfo/PDB/Native/Hash.h"
18 #include "llvm/DebugInfo/PDB/Native/PDBFile.h"
19 #include "llvm/DebugInfo/PDB/Native/RawConstants.h"
20 #include "llvm/DebugInfo/PDB/Native/RawError.h"
21 #include "llvm/DebugInfo/PDB/Native/RawTypes.h"
22 #include "llvm/DebugInfo/PDB/Native/TpiHashing.h"
23 #include "llvm/Support/BinaryStreamReader.h"
24 #include "llvm/Support/Endian.h"
25 #include "llvm/Support/Error.h"
26 #include <algorithm>
27 #include <cstdint>
28 #include <vector>
29 
30 using namespace llvm;
31 using namespace llvm::codeview;
32 using namespace llvm::support;
33 using namespace llvm::msf;
34 using namespace llvm::pdb;
35 
36 TpiStream::TpiStream(PDBFile &File, std::unique_ptr<MappedBlockStream> Stream)
37     : Pdb(File), Stream(std::move(Stream)) {}
38 
39 TpiStream::~TpiStream() = default;
40 
41 Error TpiStream::reload() {
42   BinaryStreamReader Reader(*Stream);
43 
44   if (Reader.bytesRemaining() < sizeof(TpiStreamHeader))
45     return make_error<RawError>(raw_error_code::corrupt_file,
46                                 "TPI Stream does not contain a header.");
47 
48   if (Reader.readObject(Header))
49     return make_error<RawError>(raw_error_code::corrupt_file,
50                                 "TPI Stream does not contain a header.");
51 
52   if (Header->Version != PdbTpiV80)
53     return make_error<RawError>(raw_error_code::corrupt_file,
54                                 "Unsupported TPI Version.");
55 
56   if (Header->HeaderSize != sizeof(TpiStreamHeader))
57     return make_error<RawError>(raw_error_code::corrupt_file,
58                                 "Corrupt TPI Header size.");
59 
60   if (Header->HashKeySize != sizeof(ulittle32_t))
61     return make_error<RawError>(raw_error_code::corrupt_file,
62                                 "TPI Stream expected 4 byte hash key size.");
63 
64   if (Header->NumHashBuckets < MinTpiHashBuckets ||
65       Header->NumHashBuckets > MaxTpiHashBuckets)
66     return make_error<RawError>(raw_error_code::corrupt_file,
67                                 "TPI Stream Invalid number of hash buckets.");
68 
69   // The actual type records themselves come from this stream
70   if (auto EC =
71           Reader.readSubstream(TypeRecordsSubstream, Header->TypeRecordBytes))
72     return EC;
73 
74   BinaryStreamReader RecordReader(TypeRecordsSubstream.StreamData);
75   if (auto EC =
76           RecordReader.readArray(TypeRecords, TypeRecordsSubstream.size()))
77     return EC;
78 
79   // Hash indices, hash values, etc come from the hash stream.
80   if (Header->HashStreamIndex != kInvalidStreamIndex) {
81     if (Header->HashStreamIndex >= Pdb.getNumStreams())
82       return make_error<RawError>(raw_error_code::corrupt_file,
83                                   "Invalid TPI hash stream index.");
84 
85     auto HS = MappedBlockStream::createIndexedStream(
86         Pdb.getMsfLayout(), Pdb.getMsfBuffer(), Header->HashStreamIndex,
87         Pdb.getAllocator());
88     BinaryStreamReader HSR(*HS);
89 
90     // There should be a hash value for every type record, or no hashes at all.
91     uint32_t NumHashValues =
92         Header->HashValueBuffer.Length / sizeof(ulittle32_t);
93     if (NumHashValues != getNumTypeRecords() && NumHashValues != 0)
94       return make_error<RawError>(
95           raw_error_code::corrupt_file,
96           "TPI hash count does not match with the number of type records.");
97     HSR.setOffset(Header->HashValueBuffer.Off);
98     if (auto EC = HSR.readArray(HashValues, NumHashValues))
99       return EC;
100 
101     HSR.setOffset(Header->IndexOffsetBuffer.Off);
102     uint32_t NumTypeIndexOffsets =
103         Header->IndexOffsetBuffer.Length / sizeof(TypeIndexOffset);
104     if (auto EC = HSR.readArray(TypeIndexOffsets, NumTypeIndexOffsets))
105       return EC;
106 
107     if (Header->HashAdjBuffer.Length > 0) {
108       HSR.setOffset(Header->HashAdjBuffer.Off);
109       if (auto EC = HashAdjusters.load(HSR))
110         return EC;
111     }
112 
113     HashStream = std::move(HS);
114   }
115 
116   Types = llvm::make_unique<LazyRandomTypeCollection>(
117       TypeRecords, getNumTypeRecords(), getTypeIndexOffsets());
118   return Error::success();
119 }
120 
121 PdbRaw_TpiVer TpiStream::getTpiVersion() const {
122   uint32_t Value = Header->Version;
123   return static_cast<PdbRaw_TpiVer>(Value);
124 }
125 
126 uint32_t TpiStream::TypeIndexBegin() const { return Header->TypeIndexBegin; }
127 
128 uint32_t TpiStream::TypeIndexEnd() const { return Header->TypeIndexEnd; }
129 
130 uint32_t TpiStream::getNumTypeRecords() const {
131   return TypeIndexEnd() - TypeIndexBegin();
132 }
133 
134 uint16_t TpiStream::getTypeHashStreamIndex() const {
135   return Header->HashStreamIndex;
136 }
137 
138 uint16_t TpiStream::getTypeHashStreamAuxIndex() const {
139   return Header->HashAuxStreamIndex;
140 }
141 
142 uint32_t TpiStream::getNumHashBuckets() const { return Header->NumHashBuckets; }
143 uint32_t TpiStream::getHashKeySize() const { return Header->HashKeySize; }
144 
145 void TpiStream::buildHashMap() {
146   if (!HashMap.empty())
147     return;
148   if (HashValues.empty())
149     return;
150 
151   HashMap.resize(Header->NumHashBuckets);
152 
153   TypeIndex TIB{Header->TypeIndexBegin};
154   TypeIndex TIE{Header->TypeIndexEnd};
155   while (TIB < TIE) {
156     uint32_t HV = HashValues[TIB.toArrayIndex()];
157     HashMap[HV].push_back(TIB++);
158   }
159 }
160 
161 std::vector<TypeIndex> TpiStream::findRecordsByName(StringRef Name) const {
162   if (!supportsTypeLookup())
163     const_cast<TpiStream*>(this)->buildHashMap();
164 
165   uint32_t Bucket = hashStringV1(Name) % Header->NumHashBuckets;
166   if (Bucket > HashMap.size())
167     return {};
168 
169   std::vector<TypeIndex> Result;
170   for (TypeIndex TI : HashMap[Bucket]) {
171     std::string ThisName = computeTypeName(*Types, TI);
172     if (ThisName == Name)
173       Result.push_back(TI);
174   }
175   return Result;
176 }
177 
178 bool TpiStream::supportsTypeLookup() const { return !HashMap.empty(); }
179 
180 Expected<TypeIndex>
181 TpiStream::findFullDeclForForwardRef(TypeIndex ForwardRefTI) const {
182   if (!supportsTypeLookup())
183     const_cast<TpiStream*>(this)->buildHashMap();
184 
185   CVType F = Types->getType(ForwardRefTI);
186   if (!isUdtForwardRef(F))
187     return ForwardRefTI;
188 
189   Expected<TagRecordHash> ForwardTRH = hashTagRecord(F);
190   if (!ForwardTRH)
191     return ForwardTRH.takeError();
192 
193   uint32_t BucketIdx = ForwardTRH->FullRecordHash % Header->NumHashBuckets;
194 
195   for (TypeIndex TI : HashMap[BucketIdx]) {
196     CVType CVT = Types->getType(TI);
197     if (CVT.kind() != F.kind())
198       continue;
199 
200     Expected<TagRecordHash> FullTRH = hashTagRecord(CVT);
201     if (!FullTRH)
202       return FullTRH.takeError();
203     if (ForwardTRH->FullRecordHash != FullTRH->FullRecordHash)
204       continue;
205     TagRecord &ForwardTR = ForwardTRH->getRecord();
206     TagRecord &FullTR = FullTRH->getRecord();
207 
208     if (!ForwardTR.hasUniqueName()) {
209       if (ForwardTR.getName() == FullTR.getName())
210         return TI;
211       continue;
212     }
213 
214     if (!FullTR.hasUniqueName())
215       continue;
216     if (ForwardTR.getUniqueName() == FullTR.getUniqueName())
217       return TI;
218   }
219   return ForwardRefTI;
220 }
221 
222 codeview::CVType TpiStream::getType(codeview::TypeIndex Index) {
223   assert(!Index.isSimple());
224   return Types->getType(Index);
225 }
226 
227 BinarySubstreamRef TpiStream::getTypeRecordsSubstream() const {
228   return TypeRecordsSubstream;
229 }
230 
231 FixedStreamArray<support::ulittle32_t> TpiStream::getHashValues() const {
232   return HashValues;
233 }
234 
235 FixedStreamArray<TypeIndexOffset> TpiStream::getTypeIndexOffsets() const {
236   return TypeIndexOffsets;
237 }
238 
239 HashTable<support::ulittle32_t> &TpiStream::getHashAdjusters() {
240   return HashAdjusters;
241 }
242 
243 CVTypeRange TpiStream::types(bool *HadError) const {
244   return make_range(TypeRecords.begin(HadError), TypeRecords.end());
245 }
246 
247 Error TpiStream::commit() { return Error::success(); }
248