1 //===- TpiStreamBuilder.cpp - -------------------------------------------===//
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/TpiStreamBuilder.h"
10 #include "llvm/ADT/ArrayRef.h"
11 #include "llvm/ADT/STLExtras.h"
12 #include "llvm/DebugInfo/CodeView/TypeIndex.h"
13 #include "llvm/DebugInfo/CodeView/TypeRecord.h"
14 #include "llvm/DebugInfo/MSF/MSFBuilder.h"
15 #include "llvm/DebugInfo/MSF/MappedBlockStream.h"
16 #include "llvm/DebugInfo/PDB/Native/PDBFile.h"
17 #include "llvm/DebugInfo/PDB/Native/RawError.h"
18 #include "llvm/DebugInfo/PDB/Native/RawTypes.h"
19 #include "llvm/Support/Allocator.h"
20 #include "llvm/Support/BinaryByteStream.h"
21 #include "llvm/Support/BinaryStreamArray.h"
22 #include "llvm/Support/BinaryStreamReader.h"
23 #include "llvm/Support/BinaryStreamWriter.h"
24 #include "llvm/Support/Endian.h"
25 #include "llvm/Support/Error.h"
26 #include <algorithm>
27 #include <cstdint>
28
29 using namespace llvm;
30 using namespace llvm::msf;
31 using namespace llvm::pdb;
32 using namespace llvm::support;
33
TpiStreamBuilder(MSFBuilder & Msf,uint32_t StreamIdx)34 TpiStreamBuilder::TpiStreamBuilder(MSFBuilder &Msf, uint32_t StreamIdx)
35 : Msf(Msf), Allocator(Msf.getAllocator()), Header(nullptr), Idx(StreamIdx) {
36 }
37
38 TpiStreamBuilder::~TpiStreamBuilder() = default;
39
setVersionHeader(PdbRaw_TpiVer Version)40 void TpiStreamBuilder::setVersionHeader(PdbRaw_TpiVer Version) {
41 VerHeader = Version;
42 }
43
addTypeRecord(ArrayRef<uint8_t> Record,Optional<uint32_t> Hash)44 void TpiStreamBuilder::addTypeRecord(ArrayRef<uint8_t> Record,
45 Optional<uint32_t> Hash) {
46 // If we just crossed an 8KB threshold, add a type index offset.
47 assert(((Record.size() & 3) == 0) &&
48 "The type record's size is not a multiple of 4 bytes which will "
49 "cause misalignment in the output TPI stream!");
50 size_t NewSize = TypeRecordBytes + Record.size();
51 constexpr size_t EightKB = 8 * 1024;
52 if (NewSize / EightKB > TypeRecordBytes / EightKB || TypeRecords.empty()) {
53 TypeIndexOffsets.push_back(
54 {codeview::TypeIndex(codeview::TypeIndex::FirstNonSimpleIndex +
55 TypeRecords.size()),
56 ulittle32_t(TypeRecordBytes)});
57 }
58 TypeRecordBytes = NewSize;
59
60 TypeRecords.push_back(Record);
61 if (Hash)
62 TypeHashes.push_back(*Hash);
63 }
64
finalize()65 Error TpiStreamBuilder::finalize() {
66 if (Header)
67 return Error::success();
68
69 TpiStreamHeader *H = Allocator.Allocate<TpiStreamHeader>();
70
71 uint32_t Count = TypeRecords.size();
72
73 H->Version = VerHeader;
74 H->HeaderSize = sizeof(TpiStreamHeader);
75 H->TypeIndexBegin = codeview::TypeIndex::FirstNonSimpleIndex;
76 H->TypeIndexEnd = H->TypeIndexBegin + Count;
77 H->TypeRecordBytes = TypeRecordBytes;
78
79 H->HashStreamIndex = HashStreamIndex;
80 H->HashAuxStreamIndex = kInvalidStreamIndex;
81 H->HashKeySize = sizeof(ulittle32_t);
82 H->NumHashBuckets = MaxTpiHashBuckets - 1;
83
84 // Recall that hash values go into a completely different stream identified by
85 // the `HashStreamIndex` field of the `TpiStreamHeader`. Therefore, the data
86 // begins at offset 0 of this independent stream.
87 H->HashValueBuffer.Off = 0;
88 H->HashValueBuffer.Length = calculateHashBufferSize();
89
90 // We never write any adjustments into our PDBs, so this is usually some
91 // offset with zero length.
92 H->HashAdjBuffer.Off = H->HashValueBuffer.Off + H->HashValueBuffer.Length;
93 H->HashAdjBuffer.Length = 0;
94
95 H->IndexOffsetBuffer.Off = H->HashAdjBuffer.Off + H->HashAdjBuffer.Length;
96 H->IndexOffsetBuffer.Length = calculateIndexOffsetSize();
97
98 Header = H;
99 return Error::success();
100 }
101
calculateSerializedLength()102 uint32_t TpiStreamBuilder::calculateSerializedLength() {
103 return sizeof(TpiStreamHeader) + TypeRecordBytes;
104 }
105
calculateHashBufferSize() const106 uint32_t TpiStreamBuilder::calculateHashBufferSize() const {
107 assert((TypeRecords.size() == TypeHashes.size() || TypeHashes.empty()) &&
108 "either all or no type records should have hashes");
109 return TypeHashes.size() * sizeof(ulittle32_t);
110 }
111
calculateIndexOffsetSize() const112 uint32_t TpiStreamBuilder::calculateIndexOffsetSize() const {
113 return TypeIndexOffsets.size() * sizeof(codeview::TypeIndexOffset);
114 }
115
finalizeMsfLayout()116 Error TpiStreamBuilder::finalizeMsfLayout() {
117 uint32_t Length = calculateSerializedLength();
118 if (auto EC = Msf.setStreamSize(Idx, Length))
119 return EC;
120
121 uint32_t HashStreamSize =
122 calculateHashBufferSize() + calculateIndexOffsetSize();
123
124 if (HashStreamSize == 0)
125 return Error::success();
126
127 auto ExpectedIndex = Msf.addStream(HashStreamSize);
128 if (!ExpectedIndex)
129 return ExpectedIndex.takeError();
130 HashStreamIndex = *ExpectedIndex;
131 if (!TypeHashes.empty()) {
132 ulittle32_t *H = Allocator.Allocate<ulittle32_t>(TypeHashes.size());
133 MutableArrayRef<ulittle32_t> HashBuffer(H, TypeHashes.size());
134 for (uint32_t I = 0; I < TypeHashes.size(); ++I) {
135 HashBuffer[I] = TypeHashes[I] % (MaxTpiHashBuckets - 1);
136 }
137 ArrayRef<uint8_t> Bytes(
138 reinterpret_cast<const uint8_t *>(HashBuffer.data()),
139 calculateHashBufferSize());
140 HashValueStream =
141 std::make_unique<BinaryByteStream>(Bytes, llvm::support::little);
142 }
143 return Error::success();
144 }
145
commit(const msf::MSFLayout & Layout,WritableBinaryStreamRef Buffer)146 Error TpiStreamBuilder::commit(const msf::MSFLayout &Layout,
147 WritableBinaryStreamRef Buffer) {
148 if (auto EC = finalize())
149 return EC;
150
151 auto InfoS = WritableMappedBlockStream::createIndexedStream(Layout, Buffer,
152 Idx, Allocator);
153
154 BinaryStreamWriter Writer(*InfoS);
155 if (auto EC = Writer.writeObject(*Header))
156 return EC;
157
158 for (auto Rec : TypeRecords) {
159 assert(!Rec.empty() && "Attempting to write an empty type record shifts "
160 "all offsets in the TPI stream!");
161 assert(((Rec.size() & 3) == 0) &&
162 "The type record's size is not a multiple of 4 bytes which will "
163 "cause misalignment in the output TPI stream!");
164 if (auto EC = Writer.writeBytes(Rec))
165 return EC;
166 }
167
168 if (HashStreamIndex != kInvalidStreamIndex) {
169 auto HVS = WritableMappedBlockStream::createIndexedStream(
170 Layout, Buffer, HashStreamIndex, Allocator);
171 BinaryStreamWriter HW(*HVS);
172 if (HashValueStream) {
173 if (auto EC = HW.writeStreamRef(*HashValueStream))
174 return EC;
175 }
176
177 for (auto &IndexOffset : TypeIndexOffsets) {
178 if (auto EC = HW.writeObject(IndexOffset))
179 return EC;
180 }
181 }
182
183 return Error::success();
184 }
185