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/RecordSerialization.h"
13#include "llvm/DebugInfo/CodeView/TypeIndex.h"
14#include "llvm/DebugInfo/MSF/MSFBuilder.h"
15#include "llvm/DebugInfo/MSF/MappedBlockStream.h"
16#include "llvm/DebugInfo/PDB/Native/RawTypes.h"
17#include "llvm/Support/Allocator.h"
18#include "llvm/Support/BinaryByteStream.h"
19#include "llvm/Support/BinaryStreamWriter.h"
20#include "llvm/Support/Endian.h"
21#include "llvm/Support/Error.h"
22#include "llvm/Support/TimeProfiler.h"
23#include <algorithm>
24#include <cstdint>
25#include <numeric>
26
27using namespace llvm;
28using namespace llvm::msf;
29using namespace llvm::pdb;
30using namespace llvm::support;
31
32TpiStreamBuilder::TpiStreamBuilder(MSFBuilder &Msf, uint32_t StreamIdx)
33 : Msf(Msf), Allocator(Msf.getAllocator()), Header(nullptr), Idx(StreamIdx) {
34}
35
36TpiStreamBuilder::~TpiStreamBuilder() = default;
37
38void TpiStreamBuilder::setVersionHeader(PdbRaw_TpiVer Version) {
39 VerHeader = Version;
40}
41
42void TpiStreamBuilder::updateTypeIndexOffsets(ArrayRef<uint16_t> Sizes) {
43 // If we just crossed an 8KB threshold, add a type index offset.
44 for (uint16_t Size : Sizes) {
45 size_t NewSize = TypeRecordBytes + Size;
46 constexpr size_t EightKB = 8 * 1024;
47 if (NewSize / EightKB > TypeRecordBytes / EightKB || TypeRecordCount == 0) {
48 TypeIndexOffsets.push_back(
49 x: {.Type: codeview::TypeIndex(codeview::TypeIndex::FirstNonSimpleIndex +
50 TypeRecordCount),
51 .Offset: ulittle32_t(TypeRecordBytes)});
52 }
53 ++TypeRecordCount;
54 TypeRecordBytes = NewSize;
55 }
56}
57
58void TpiStreamBuilder::addTypeRecord(ArrayRef<uint8_t> Record,
59 std::optional<uint32_t> Hash) {
60 assert(((Record.size() & 3) == 0) &&
61 "The type record's size is not a multiple of 4 bytes which will "
62 "cause misalignment in the output TPI stream!");
63 assert(Record.size() <= codeview::MaxRecordLength);
64 uint16_t OneSize = (uint16_t)Record.size();
65 updateTypeIndexOffsets(Sizes: ArrayRef(&OneSize, 1));
66
67 TypeRecBuffers.push_back(x: Record);
68 // FIXME: Require it.
69 if (Hash)
70 TypeHashes.push_back(x: *Hash);
71}
72
73void TpiStreamBuilder::addTypeRecords(ArrayRef<uint8_t> Types,
74 ArrayRef<uint16_t> Sizes,
75 ArrayRef<uint32_t> Hashes) {
76 // Ignore empty type buffers. There should be no hashes or sizes in this case.
77 if (Types.empty()) {
78 assert(Sizes.empty() && Hashes.empty());
79 return;
80 }
81
82 assert(((Types.size() & 3) == 0) &&
83 "The type record's size is not a multiple of 4 bytes which will "
84 "cause misalignment in the output TPI stream!");
85 assert(Sizes.size() == Hashes.size() && "sizes and hashes should be in sync");
86 assert(std::accumulate(Sizes.begin(), Sizes.end(), 0U) == Types.size() &&
87 "sizes of type records should sum to the size of the types");
88 updateTypeIndexOffsets(Sizes);
89
90 TypeRecBuffers.push_back(x: Types);
91 llvm::append_range(C&: TypeHashes, R&: Hashes);
92}
93
94Error TpiStreamBuilder::finalize() {
95 if (Header)
96 return Error::success();
97
98 TpiStreamHeader *H = Allocator.Allocate<TpiStreamHeader>();
99
100 H->Version = VerHeader;
101 H->HeaderSize = sizeof(TpiStreamHeader);
102 H->TypeIndexBegin = codeview::TypeIndex::FirstNonSimpleIndex;
103 H->TypeIndexEnd = H->TypeIndexBegin + TypeRecordCount;
104 H->TypeRecordBytes = TypeRecordBytes;
105
106 H->HashStreamIndex = HashStreamIndex;
107 H->HashAuxStreamIndex = kInvalidStreamIndex;
108 H->HashKeySize = sizeof(ulittle32_t);
109 H->NumHashBuckets = MaxTpiHashBuckets - 1;
110
111 // Recall that hash values go into a completely different stream identified by
112 // the `HashStreamIndex` field of the `TpiStreamHeader`. Therefore, the data
113 // begins at offset 0 of this independent stream.
114 H->HashValueBuffer.Off = 0;
115 H->HashValueBuffer.Length = calculateHashBufferSize();
116
117 // We never write any adjustments into our PDBs, so this is usually some
118 // offset with zero length.
119 H->HashAdjBuffer.Off = H->HashValueBuffer.Off + H->HashValueBuffer.Length;
120 H->HashAdjBuffer.Length = 0;
121
122 H->IndexOffsetBuffer.Off = H->HashAdjBuffer.Off + H->HashAdjBuffer.Length;
123 H->IndexOffsetBuffer.Length = calculateIndexOffsetSize();
124
125 Header = H;
126 return Error::success();
127}
128
129uint32_t TpiStreamBuilder::calculateSerializedLength() {
130 return sizeof(TpiStreamHeader) + TypeRecordBytes;
131}
132
133uint32_t TpiStreamBuilder::calculateHashBufferSize() const {
134 assert((TypeRecordCount == TypeHashes.size() || TypeHashes.empty()) &&
135 "either all or no type records should have hashes");
136 return TypeHashes.size() * sizeof(ulittle32_t);
137}
138
139uint32_t TpiStreamBuilder::calculateIndexOffsetSize() const {
140 return TypeIndexOffsets.size() * sizeof(codeview::TypeIndexOffset);
141}
142
143Error TpiStreamBuilder::finalizeMsfLayout() {
144 uint32_t Length = calculateSerializedLength();
145 if (auto EC = Msf.setStreamSize(Idx, Size: Length))
146 return EC;
147
148 uint32_t HashStreamSize =
149 calculateHashBufferSize() + calculateIndexOffsetSize();
150
151 if (HashStreamSize == 0)
152 return Error::success();
153
154 auto ExpectedIndex = Msf.addStream(Size: HashStreamSize);
155 if (!ExpectedIndex)
156 return ExpectedIndex.takeError();
157 HashStreamIndex = *ExpectedIndex;
158 if (!TypeHashes.empty()) {
159 ulittle32_t *H = Allocator.Allocate<ulittle32_t>(Num: TypeHashes.size());
160 MutableArrayRef<ulittle32_t> HashBuffer(H, TypeHashes.size());
161 for (uint32_t I = 0; I < TypeHashes.size(); ++I) {
162 HashBuffer[I] = TypeHashes[I] % (MaxTpiHashBuckets - 1);
163 }
164 ArrayRef<uint8_t> Bytes(
165 reinterpret_cast<const uint8_t *>(HashBuffer.data()),
166 calculateHashBufferSize());
167 HashValueStream =
168 std::make_unique<BinaryByteStream>(args&: Bytes, args: llvm::endianness::little);
169 }
170 return Error::success();
171}
172
173Error TpiStreamBuilder::commit(const msf::MSFLayout &Layout,
174 WritableBinaryStreamRef Buffer) {
175 llvm::TimeTraceScope timeScope("Commit TPI stream");
176 if (auto EC = finalize())
177 return EC;
178
179 auto InfoS = WritableMappedBlockStream::createIndexedStream(Layout, MsfData: Buffer,
180 StreamIndex: Idx, Allocator);
181
182 BinaryStreamWriter Writer(*InfoS);
183 if (auto EC = Writer.writeObject(Obj: *Header))
184 return EC;
185
186 for (auto Rec : TypeRecBuffers) {
187 assert(!Rec.empty() && "Attempting to write an empty type record shifts "
188 "all offsets in the TPI stream!");
189 assert(((Rec.size() & 3) == 0) &&
190 "The type record's size is not a multiple of 4 bytes which will "
191 "cause misalignment in the output TPI stream!");
192 if (auto EC = Writer.writeBytes(Buffer: Rec))
193 return EC;
194 }
195
196 if (HashStreamIndex != kInvalidStreamIndex) {
197 auto HVS = WritableMappedBlockStream::createIndexedStream(
198 Layout, MsfData: Buffer, StreamIndex: HashStreamIndex, Allocator);
199 BinaryStreamWriter HW(*HVS);
200 if (HashValueStream) {
201 if (auto EC = HW.writeStreamRef(Ref: *HashValueStream))
202 return EC;
203 }
204
205 for (auto &IndexOffset : TypeIndexOffsets) {
206 if (auto EC = HW.writeObject(Obj: IndexOffset))
207 return EC;
208 }
209 }
210
211 return Error::success();
212}
213

source code of llvm/lib/DebugInfo/PDB/Native/TpiStreamBuilder.cpp