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