1 //===- CodeViewRecordIO.cpp -------------------------------------*- C++ -*-===//
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/CodeView/CodeViewRecordIO.h"
10 #include "llvm/DebugInfo/CodeView/CodeView.h"
11 #include "llvm/DebugInfo/CodeView/RecordSerialization.h"
12 #include "llvm/Support/BinaryStreamReader.h"
13 #include "llvm/Support/BinaryStreamWriter.h"
14
15 using namespace llvm;
16 using namespace llvm::codeview;
17
beginRecord(Optional<uint32_t> MaxLength)18 Error CodeViewRecordIO::beginRecord(Optional<uint32_t> MaxLength) {
19 RecordLimit Limit;
20 Limit.MaxLength = MaxLength;
21 Limit.BeginOffset = getCurrentOffset();
22 Limits.push_back(Limit);
23 resetStreamedLen();
24 return Error::success();
25 }
26
endRecord()27 Error CodeViewRecordIO::endRecord() {
28 assert(!Limits.empty() && "Not in a record!");
29 Limits.pop_back();
30 // We would like to assert that we actually read / wrote all the bytes that we
31 // expected to for this record, but unfortunately we can't do this. Some
32 // producers such as MASM over-allocate for certain types of records and
33 // commit the extraneous data, so when reading we can't be sure every byte
34 // will have been read. And when writing we over-allocate temporarily since
35 // we don't know how big the record is until we're finished writing it, so
36 // even though we don't commit the extraneous data, we still can't guarantee
37 // we're at the end of the allocated data.
38
39 if (isStreaming()) {
40 // For streaming mode, add padding to align with 4 byte boundaries for each
41 // record
42 uint32_t Align = getStreamedLen() % 4;
43 if (Align == 0)
44 return Error::success();
45
46 int PaddingBytes = 4 - Align;
47 while (PaddingBytes > 0) {
48 char Pad = static_cast<uint8_t>(LF_PAD0 + PaddingBytes);
49 StringRef BytesSR = StringRef(&Pad, sizeof(Pad));
50 Streamer->EmitBytes(BytesSR);
51 --PaddingBytes;
52 }
53 }
54 return Error::success();
55 }
56
maxFieldLength() const57 uint32_t CodeViewRecordIO::maxFieldLength() const {
58 if (isStreaming())
59 return 0;
60
61 assert(!Limits.empty() && "Not in a record!");
62
63 // The max length of the next field is the minimum of all lengths that would
64 // be allowed by any of the sub-records we're in. In practice, we can only
65 // ever be at most 1 sub-record deep (in a FieldList), but this works for
66 // the general case.
67 uint32_t Offset = getCurrentOffset();
68 Optional<uint32_t> Min = Limits.front().bytesRemaining(Offset);
69 for (auto X : makeArrayRef(Limits).drop_front()) {
70 Optional<uint32_t> ThisMin = X.bytesRemaining(Offset);
71 if (ThisMin.hasValue())
72 Min = (Min.hasValue()) ? std::min(*Min, *ThisMin) : *ThisMin;
73 }
74 assert(Min.hasValue() && "Every field must have a maximum length!");
75
76 return *Min;
77 }
78
padToAlignment(uint32_t Align)79 Error CodeViewRecordIO::padToAlignment(uint32_t Align) {
80 if (isReading())
81 return Reader->padToAlignment(Align);
82 return Writer->padToAlignment(Align);
83 }
84
skipPadding()85 Error CodeViewRecordIO::skipPadding() {
86 assert(!isWriting() && "Cannot skip padding while writing!");
87
88 if (Reader->bytesRemaining() == 0)
89 return Error::success();
90
91 uint8_t Leaf = Reader->peek();
92 if (Leaf < LF_PAD0)
93 return Error::success();
94 // Leaf is greater than 0xf0. We should advance by the number of bytes in
95 // the low 4 bits.
96 unsigned BytesToAdvance = Leaf & 0x0F;
97 return Reader->skip(BytesToAdvance);
98 }
99
mapByteVectorTail(ArrayRef<uint8_t> & Bytes,const Twine & Comment)100 Error CodeViewRecordIO::mapByteVectorTail(ArrayRef<uint8_t> &Bytes,
101 const Twine &Comment) {
102 if (isStreaming()) {
103 emitComment(Comment);
104 Streamer->EmitBinaryData(toStringRef(Bytes));
105 incrStreamedLen(Bytes.size());
106 } else if (isWriting()) {
107 if (auto EC = Writer->writeBytes(Bytes))
108 return EC;
109 } else {
110 if (auto EC = Reader->readBytes(Bytes, Reader->bytesRemaining()))
111 return EC;
112 }
113 return Error::success();
114 }
115
mapByteVectorTail(std::vector<uint8_t> & Bytes,const Twine & Comment)116 Error CodeViewRecordIO::mapByteVectorTail(std::vector<uint8_t> &Bytes,
117 const Twine &Comment) {
118 ArrayRef<uint8_t> BytesRef(Bytes);
119 if (auto EC = mapByteVectorTail(BytesRef, Comment))
120 return EC;
121 if (!isWriting())
122 Bytes.assign(BytesRef.begin(), BytesRef.end());
123
124 return Error::success();
125 }
126
mapInteger(TypeIndex & TypeInd,const Twine & Comment)127 Error CodeViewRecordIO::mapInteger(TypeIndex &TypeInd, const Twine &Comment) {
128 if (isStreaming()) {
129 emitComment(Comment);
130 Streamer->EmitIntValue(TypeInd.getIndex(), sizeof(TypeInd.getIndex()));
131 incrStreamedLen(sizeof(TypeInd.getIndex()));
132 } else if (isWriting()) {
133 if (auto EC = Writer->writeInteger(TypeInd.getIndex()))
134 return EC;
135 } else {
136 uint32_t I;
137 if (auto EC = Reader->readInteger(I))
138 return EC;
139 TypeInd.setIndex(I);
140 }
141 return Error::success();
142 }
143
mapEncodedInteger(int64_t & Value,const Twine & Comment)144 Error CodeViewRecordIO::mapEncodedInteger(int64_t &Value,
145 const Twine &Comment) {
146 if (isStreaming()) {
147 if (Value >= 0)
148 emitEncodedUnsignedInteger(static_cast<uint64_t>(Value), Comment);
149 else
150 emitEncodedSignedInteger(Value, Comment);
151 } else if (isWriting()) {
152 if (Value >= 0) {
153 if (auto EC = writeEncodedUnsignedInteger(static_cast<uint64_t>(Value)))
154 return EC;
155 } else {
156 if (auto EC = writeEncodedSignedInteger(Value))
157 return EC;
158 }
159 } else {
160 APSInt N;
161 if (auto EC = consume(*Reader, N))
162 return EC;
163 Value = N.getExtValue();
164 }
165
166 return Error::success();
167 }
168
mapEncodedInteger(uint64_t & Value,const Twine & Comment)169 Error CodeViewRecordIO::mapEncodedInteger(uint64_t &Value,
170 const Twine &Comment) {
171 if (isStreaming())
172 emitEncodedUnsignedInteger(Value, Comment);
173 else if (isWriting()) {
174 if (auto EC = writeEncodedUnsignedInteger(Value))
175 return EC;
176 } else {
177 APSInt N;
178 if (auto EC = consume(*Reader, N))
179 return EC;
180 Value = N.getZExtValue();
181 }
182 return Error::success();
183 }
184
mapEncodedInteger(APSInt & Value,const Twine & Comment)185 Error CodeViewRecordIO::mapEncodedInteger(APSInt &Value, const Twine &Comment) {
186 if (isStreaming()) {
187 if (Value.isSigned())
188 emitEncodedSignedInteger(Value.getSExtValue(), Comment);
189 else
190 emitEncodedUnsignedInteger(Value.getZExtValue(), Comment);
191 } else if (isWriting()) {
192 if (Value.isSigned())
193 return writeEncodedSignedInteger(Value.getSExtValue());
194 return writeEncodedUnsignedInteger(Value.getZExtValue());
195 } else
196 return consume(*Reader, Value);
197 return Error::success();
198 }
199
mapStringZ(StringRef & Value,const Twine & Comment)200 Error CodeViewRecordIO::mapStringZ(StringRef &Value, const Twine &Comment) {
201 if (isStreaming()) {
202 auto NullTerminatedString = StringRef(Value.data(), Value.size() + 1);
203 emitComment(Comment);
204 Streamer->EmitBytes(NullTerminatedString);
205 incrStreamedLen(NullTerminatedString.size());
206 } else if (isWriting()) {
207 // Truncate if we attempt to write too much.
208 StringRef S = Value.take_front(maxFieldLength() - 1);
209 if (auto EC = Writer->writeCString(S))
210 return EC;
211 } else {
212 if (auto EC = Reader->readCString(Value))
213 return EC;
214 }
215 return Error::success();
216 }
217
mapGuid(GUID & Guid,const Twine & Comment)218 Error CodeViewRecordIO::mapGuid(GUID &Guid, const Twine &Comment) {
219 constexpr uint32_t GuidSize = 16;
220
221 if (isStreaming()) {
222 StringRef GuidSR =
223 StringRef((reinterpret_cast<const char *>(&Guid)), GuidSize);
224 emitComment(Comment);
225 Streamer->EmitBytes(GuidSR);
226 incrStreamedLen(GuidSize);
227 return Error::success();
228 }
229
230 if (maxFieldLength() < GuidSize)
231 return make_error<CodeViewError>(cv_error_code::insufficient_buffer);
232
233 if (isWriting()) {
234 if (auto EC = Writer->writeBytes(Guid.Guid))
235 return EC;
236 } else {
237 ArrayRef<uint8_t> GuidBytes;
238 if (auto EC = Reader->readBytes(GuidBytes, GuidSize))
239 return EC;
240 memcpy(Guid.Guid, GuidBytes.data(), GuidSize);
241 }
242 return Error::success();
243 }
244
mapStringZVectorZ(std::vector<StringRef> & Value,const Twine & Comment)245 Error CodeViewRecordIO::mapStringZVectorZ(std::vector<StringRef> &Value,
246 const Twine &Comment) {
247
248 if (!isReading()) {
249 emitComment(Comment);
250 for (auto V : Value) {
251 if (auto EC = mapStringZ(V))
252 return EC;
253 }
254 uint8_t FinalZero = 0;
255 if (auto EC = mapInteger(FinalZero))
256 return EC;
257 } else {
258 StringRef S;
259 if (auto EC = mapStringZ(S))
260 return EC;
261 while (!S.empty()) {
262 Value.push_back(S);
263 if (auto EC = mapStringZ(S))
264 return EC;
265 };
266 }
267 return Error::success();
268 }
269
emitEncodedSignedInteger(const int64_t & Value,const Twine & Comment)270 void CodeViewRecordIO::emitEncodedSignedInteger(const int64_t &Value,
271 const Twine &Comment) {
272 assert(Value < 0 && "Encoded integer is not signed!");
273 if (Value >= std::numeric_limits<int8_t>::min()) {
274 Streamer->EmitIntValue(LF_CHAR, 2);
275 emitComment(Comment);
276 Streamer->EmitIntValue(Value, 1);
277 incrStreamedLen(3);
278 } else if (Value >= std::numeric_limits<int16_t>::min()) {
279 Streamer->EmitIntValue(LF_SHORT, 2);
280 emitComment(Comment);
281 Streamer->EmitIntValue(Value, 2);
282 incrStreamedLen(4);
283 } else if (Value >= std::numeric_limits<int32_t>::min()) {
284 Streamer->EmitIntValue(LF_LONG, 2);
285 emitComment(Comment);
286 Streamer->EmitIntValue(Value, 4);
287 incrStreamedLen(6);
288 } else {
289 Streamer->EmitIntValue(LF_QUADWORD, 2);
290 emitComment(Comment);
291 Streamer->EmitIntValue(Value, 4);
292 incrStreamedLen(6);
293 }
294 }
295
emitEncodedUnsignedInteger(const uint64_t & Value,const Twine & Comment)296 void CodeViewRecordIO::emitEncodedUnsignedInteger(const uint64_t &Value,
297 const Twine &Comment) {
298 if (Value < LF_NUMERIC) {
299 emitComment(Comment);
300 Streamer->EmitIntValue(Value, 2);
301 incrStreamedLen(2);
302 } else if (Value <= std::numeric_limits<uint16_t>::max()) {
303 Streamer->EmitIntValue(LF_USHORT, 2);
304 emitComment(Comment);
305 Streamer->EmitIntValue(Value, 2);
306 incrStreamedLen(4);
307 } else if (Value <= std::numeric_limits<uint32_t>::max()) {
308 Streamer->EmitIntValue(LF_ULONG, 2);
309 emitComment(Comment);
310 Streamer->EmitIntValue(Value, 4);
311 incrStreamedLen(6);
312 } else {
313 Streamer->EmitIntValue(LF_UQUADWORD, 2);
314 emitComment(Comment);
315 Streamer->EmitIntValue(Value, 8);
316 incrStreamedLen(6);
317 }
318 }
319
writeEncodedSignedInteger(const int64_t & Value)320 Error CodeViewRecordIO::writeEncodedSignedInteger(const int64_t &Value) {
321 assert(Value < 0 && "Encoded integer is not signed!");
322 if (Value >= std::numeric_limits<int8_t>::min()) {
323 if (auto EC = Writer->writeInteger<uint16_t>(LF_CHAR))
324 return EC;
325 if (auto EC = Writer->writeInteger<int8_t>(Value))
326 return EC;
327 } else if (Value >= std::numeric_limits<int16_t>::min()) {
328 if (auto EC = Writer->writeInteger<uint16_t>(LF_SHORT))
329 return EC;
330 if (auto EC = Writer->writeInteger<int16_t>(Value))
331 return EC;
332 } else if (Value >= std::numeric_limits<int32_t>::min()) {
333 if (auto EC = Writer->writeInteger<uint16_t>(LF_LONG))
334 return EC;
335 if (auto EC = Writer->writeInteger<int32_t>(Value))
336 return EC;
337 } else {
338 if (auto EC = Writer->writeInteger<uint16_t>(LF_QUADWORD))
339 return EC;
340 if (auto EC = Writer->writeInteger(Value))
341 return EC;
342 }
343 return Error::success();
344 }
345
writeEncodedUnsignedInteger(const uint64_t & Value)346 Error CodeViewRecordIO::writeEncodedUnsignedInteger(const uint64_t &Value) {
347 if (Value < LF_NUMERIC) {
348 if (auto EC = Writer->writeInteger<uint16_t>(Value))
349 return EC;
350 } else if (Value <= std::numeric_limits<uint16_t>::max()) {
351 if (auto EC = Writer->writeInteger<uint16_t>(LF_USHORT))
352 return EC;
353 if (auto EC = Writer->writeInteger<uint16_t>(Value))
354 return EC;
355 } else if (Value <= std::numeric_limits<uint32_t>::max()) {
356 if (auto EC = Writer->writeInteger<uint16_t>(LF_ULONG))
357 return EC;
358 if (auto EC = Writer->writeInteger<uint32_t>(Value))
359 return EC;
360 } else {
361 if (auto EC = Writer->writeInteger<uint16_t>(LF_UQUADWORD))
362 return EC;
363 if (auto EC = Writer->writeInteger(Value))
364 return EC;
365 }
366
367 return Error::success();
368 }
369