1 //===-- ReproducerInstrumentation.h -----------------------------*- C++ -*-===//
2 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
3 // See https://llvm.org/LICENSE.txt for license information.
4 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
5 //
6 //===----------------------------------------------------------------------===//
7
8 #ifndef LLDB_UTILITY_REPRODUCERINSTRUMENTATION_H
9 #define LLDB_UTILITY_REPRODUCERINSTRUMENTATION_H
10
11 #include "lldb/Utility/FileSpec.h"
12 #include "lldb/Utility/Log.h"
13 #include "lldb/Utility/Logging.h"
14
15 #include "llvm/ADT/DenseMap.h"
16 #include "llvm/ADT/StringRef.h"
17 #include "llvm/Support/ErrorHandling.h"
18
19 #include <map>
20 #include <thread>
21 #include <type_traits>
22
23 template <typename T,
24 typename std::enable_if<std::is_fundamental<T>::value, int>::type = 0>
stringify_append(llvm::raw_string_ostream & ss,const T & t)25 inline void stringify_append(llvm::raw_string_ostream &ss, const T &t) {
26 ss << t;
27 }
28
29 template <typename T, typename std::enable_if<!std::is_fundamental<T>::value,
30 int>::type = 0>
stringify_append(llvm::raw_string_ostream & ss,const T & t)31 inline void stringify_append(llvm::raw_string_ostream &ss, const T &t) {
32 ss << &t;
33 }
34
35 template <typename T>
stringify_append(llvm::raw_string_ostream & ss,T * t)36 inline void stringify_append(llvm::raw_string_ostream &ss, T *t) {
37 ss << reinterpret_cast<void *>(t);
38 }
39
40 template <typename T>
stringify_append(llvm::raw_string_ostream & ss,const T * t)41 inline void stringify_append(llvm::raw_string_ostream &ss, const T *t) {
42 ss << reinterpret_cast<const void *>(t);
43 }
44
45 template <>
46 inline void stringify_append<char>(llvm::raw_string_ostream &ss,
47 const char *t) {
48 ss << '\"' << t << '\"';
49 }
50
51 template <>
52 inline void stringify_append<std::nullptr_t>(llvm::raw_string_ostream &ss,
53 const std::nullptr_t &t) {
54 ss << "\"nullptr\"";
55 }
56
57 template <typename Head>
stringify_helper(llvm::raw_string_ostream & ss,const Head & head)58 inline void stringify_helper(llvm::raw_string_ostream &ss, const Head &head) {
59 stringify_append(ss, head);
60 }
61
62 template <typename Head, typename... Tail>
stringify_helper(llvm::raw_string_ostream & ss,const Head & head,const Tail &...tail)63 inline void stringify_helper(llvm::raw_string_ostream &ss, const Head &head,
64 const Tail &... tail) {
65 stringify_append(ss, head);
66 ss << ", ";
67 stringify_helper(ss, tail...);
68 }
69
stringify_args(const Ts &...ts)70 template <typename... Ts> inline std::string stringify_args(const Ts &... ts) {
71 std::string buffer;
72 llvm::raw_string_ostream ss(buffer);
73 stringify_helper(ss, ts...);
74 return ss.str();
75 }
76
77 // Define LLDB_REPRO_INSTR_TRACE to trace to stderr instead of LLDB's log
78 // infrastructure. This is useful when you need to see traces before the logger
79 // is initialized or enabled.
80 // #define LLDB_REPRO_INSTR_TRACE
81
82 #ifdef LLDB_REPRO_INSTR_TRACE
this_thread_id()83 inline llvm::raw_ostream &this_thread_id() {
84 size_t tid = std::hash<std::thread::id>{}(std::this_thread::get_id());
85 return llvm::errs().write_hex(tid) << " :: ";
86 }
87 #endif
88
89 #define LLDB_REGISTER_CONSTRUCTOR(Class, Signature) \
90 R.Register<Class * Signature>(&construct<Class Signature>::record, "", \
91 #Class, #Class, #Signature)
92
93 #define LLDB_REGISTER_METHOD(Result, Class, Method, Signature) \
94 R.Register( \
95 &invoke<Result(Class::*) Signature>::method<(&Class::Method)>::record, \
96 #Result, #Class, #Method, #Signature)
97
98 #define LLDB_REGISTER_METHOD_CONST(Result, Class, Method, Signature) \
99 R.Register(&invoke<Result(Class::*) \
100 Signature const>::method<(&Class::Method)>::record, \
101 #Result, #Class, #Method, #Signature)
102
103 #define LLDB_REGISTER_STATIC_METHOD(Result, Class, Method, Signature) \
104 R.Register(&invoke<Result(*) Signature>::method<(&Class::Method)>::record, \
105 #Result, #Class, #Method, #Signature)
106
107 #define LLDB_REGISTER_CHAR_PTR_METHOD_STATIC(Result, Class, Method) \
108 R.Register( \
109 &invoke<Result (*)(char *, size_t)>::method<(&Class::Method)>::record, \
110 &invoke_char_ptr<Result (*)(char *, \
111 size_t)>::method<(&Class::Method)>::record, \
112 #Result, #Class, #Method, "(char*, size_t");
113
114 #define LLDB_REGISTER_CHAR_PTR_METHOD(Result, Class, Method) \
115 R.Register(&invoke<Result (Class::*)(char *, size_t)>::method<( \
116 &Class::Method)>::record, \
117 &invoke_char_ptr<Result (Class::*)(char *, size_t)>::method<( \
118 &Class::Method)>::record, \
119 #Result, #Class, #Method, "(char*, size_t");
120
121 #define LLDB_REGISTER_CHAR_PTR_METHOD_CONST(Result, Class, Method) \
122 R.Register(&invoke<Result (Class::*)(char *, size_t) \
123 const>::method<(&Class::Method)>::record, \
124 &invoke_char_ptr<Result (Class::*)(char *, size_t) \
125 const>::method<(&Class::Method)>::record, \
126 #Result, #Class, #Method, "(char*, size_t");
127
128 #define LLDB_CONSTRUCT_(T, Class, ...) \
129 lldb_private::repro::Recorder _recorder(LLVM_PRETTY_FUNCTION); \
130 lldb_private::repro::construct<T>::handle(LLDB_GET_INSTRUMENTATION_DATA(), \
131 _recorder, Class, __VA_ARGS__);
132
133 #define LLDB_RECORD_CONSTRUCTOR(Class, Signature, ...) \
134 LLDB_CONSTRUCT_(Class Signature, this, __VA_ARGS__)
135
136 #define LLDB_RECORD_CONSTRUCTOR_NO_ARGS(Class) \
137 LLDB_CONSTRUCT_(Class(), this, lldb_private::repro::EmptyArg())
138
139 #define LLDB_RECORD_(T1, T2, ...) \
140 lldb_private::repro::Recorder _recorder(LLVM_PRETTY_FUNCTION, \
141 stringify_args(__VA_ARGS__)); \
142 if (lldb_private::repro::InstrumentationData _data = \
143 LLDB_GET_INSTRUMENTATION_DATA()) { \
144 if (lldb_private::repro::Serializer *_serializer = \
145 _data.GetSerializer()) { \
146 _recorder.Record(*_serializer, _data.GetRegistry(), \
147 &lldb_private::repro::invoke<T1>::method<T2>::record, \
148 __VA_ARGS__); \
149 } else if (lldb_private::repro::Deserializer *_deserializer = \
150 _data.GetDeserializer()) { \
151 if (_recorder.ShouldCapture()) { \
152 return lldb_private::repro::invoke<T1>::method<T2>::replay( \
153 _recorder, *_deserializer, _data.GetRegistry()); \
154 } \
155 } \
156 }
157
158 #define LLDB_RECORD_METHOD(Result, Class, Method, Signature, ...) \
159 LLDB_RECORD_(Result(Class::*) Signature, (&Class::Method), this, __VA_ARGS__)
160
161 #define LLDB_RECORD_METHOD_CONST(Result, Class, Method, Signature, ...) \
162 LLDB_RECORD_(Result(Class::*) Signature const, (&Class::Method), this, \
163 __VA_ARGS__)
164
165 #define LLDB_RECORD_METHOD_NO_ARGS(Result, Class, Method) \
166 LLDB_RECORD_(Result (Class::*)(), (&Class::Method), this)
167
168 #define LLDB_RECORD_METHOD_CONST_NO_ARGS(Result, Class, Method) \
169 LLDB_RECORD_(Result (Class::*)() const, (&Class::Method), this)
170
171 #define LLDB_RECORD_STATIC_METHOD(Result, Class, Method, Signature, ...) \
172 LLDB_RECORD_(Result(*) Signature, (&Class::Method), __VA_ARGS__)
173
174 #define LLDB_RECORD_STATIC_METHOD_NO_ARGS(Result, Class, Method) \
175 LLDB_RECORD_(Result (*)(), (&Class::Method), lldb_private::repro::EmptyArg())
176
177 #define LLDB_RECORD_CHAR_PTR_(T1, T2, StrOut, ...) \
178 lldb_private::repro::Recorder _recorder(LLVM_PRETTY_FUNCTION, \
179 stringify_args(__VA_ARGS__)); \
180 if (lldb_private::repro::InstrumentationData _data = \
181 LLDB_GET_INSTRUMENTATION_DATA()) { \
182 if (lldb_private::repro::Serializer *_serializer = \
183 _data.GetSerializer()) { \
184 _recorder.Record(*_serializer, _data.GetRegistry(), \
185 &lldb_private::repro::invoke<T1>::method<(T2)>::record, \
186 __VA_ARGS__); \
187 } else if (lldb_private::repro::Deserializer *_deserializer = \
188 _data.GetDeserializer()) { \
189 if (_recorder.ShouldCapture()) { \
190 return lldb_private::repro::invoke_char_ptr<T1>::method<T2>::replay( \
191 _recorder, *_deserializer, _data.GetRegistry(), StrOut); \
192 } \
193 } \
194 }
195
196 #define LLDB_RECORD_CHAR_PTR_METHOD(Result, Class, Method, Signature, StrOut, \
197 ...) \
198 LLDB_RECORD_CHAR_PTR_(Result(Class::*) Signature, (&Class::Method), StrOut, \
199 this, __VA_ARGS__)
200
201 #define LLDB_RECORD_CHAR_PTR_METHOD_CONST(Result, Class, Method, Signature, \
202 StrOut, ...) \
203 LLDB_RECORD_CHAR_PTR_(Result(Class::*) Signature const, (&Class::Method), \
204 StrOut, this, __VA_ARGS__)
205
206 #define LLDB_RECORD_CHAR_PTR_STATIC_METHOD(Result, Class, Method, Signature, \
207 StrOut, ...) \
208 LLDB_RECORD_CHAR_PTR_(Result(*) Signature, (&Class::Method), StrOut, \
209 __VA_ARGS__)
210
211 #define LLDB_RECORD_RESULT(Result) _recorder.RecordResult(Result, true);
212
213 /// The LLDB_RECORD_DUMMY macro is special because it doesn't actually record
214 /// anything. It's used to track API boundaries when we cannot record for
215 /// technical reasons.
216 #define LLDB_RECORD_DUMMY(Result, Class, Method, Signature, ...) \
217 lldb_private::repro::Recorder _recorder;
218
219 #define LLDB_RECORD_DUMMY_NO_ARGS(Result, Class, Method) \
220 lldb_private::repro::Recorder _recorder;
221
222 namespace lldb_private {
223 namespace repro {
224
225 template <class T>
226 struct is_trivially_serializable
227 : std::integral_constant<bool, std::is_fundamental<T>::value ||
228 std::is_enum<T>::value> {};
229
230 /// Mapping between serialized indices and their corresponding objects.
231 ///
232 /// This class is used during replay to map indices back to in-memory objects.
233 ///
234 /// When objects are constructed, they are added to this mapping using
235 /// AddObjectForIndex.
236 ///
237 /// When an object is passed to a function, its index is deserialized and
238 /// AddObjectForIndex returns the corresponding object. If there is no object
239 /// for the given index, a nullptr is returend. The latter is valid when custom
240 /// replay code is in place and the actual object is ignored.
241 class IndexToObject {
242 public:
243 /// Returns an object as a pointer for the given index or nullptr if not
244 /// present in the map.
GetObjectForIndex(unsigned idx)245 template <typename T> T *GetObjectForIndex(unsigned idx) {
246 assert(idx != 0 && "Cannot get object for sentinel");
247 void *object = GetObjectForIndexImpl(idx);
248 return static_cast<T *>(object);
249 }
250
251 /// Adds a pointer to an object to the mapping for the given index.
AddObjectForIndex(unsigned idx,T * object)252 template <typename T> T *AddObjectForIndex(unsigned idx, T *object) {
253 AddObjectForIndexImpl(
254 idx, static_cast<void *>(
255 const_cast<typename std::remove_const<T>::type *>(object)));
256 return object;
257 }
258
259 /// Adds a reference to an object to the mapping for the given index.
AddObjectForIndex(unsigned idx,T & object)260 template <typename T> T &AddObjectForIndex(unsigned idx, T &object) {
261 AddObjectForIndexImpl(
262 idx, static_cast<void *>(
263 const_cast<typename std::remove_const<T>::type *>(&object)));
264 return object;
265 }
266
267 /// Get all objects sorted by their index.
268 std::vector<void *> GetAllObjects() const;
269
270 private:
271 /// Helper method that does the actual lookup. The void* result is later cast
272 /// by the caller.
273 void *GetObjectForIndexImpl(unsigned idx);
274
275 /// Helper method that does the actual insertion.
276 void AddObjectForIndexImpl(unsigned idx, void *object);
277
278 /// Keeps a mapping between indices and their corresponding object.
279 llvm::DenseMap<unsigned, void *> m_mapping;
280 };
281
282 /// We need to differentiate between pointers to fundamental and
283 /// non-fundamental types. See the corresponding Deserializer::Read method
284 /// for the reason why.
285 struct PointerTag {};
286 struct ReferenceTag {};
287 struct ValueTag {};
288 struct FundamentalPointerTag {};
289 struct FundamentalReferenceTag {};
290
291 /// Return the deserialization tag for the given type T.
292 template <class T> struct serializer_tag {
293 typedef typename std::conditional<std::is_trivially_copyable<T>::value,
294 ValueTag, ReferenceTag>::type type;
295 };
296 template <class T> struct serializer_tag<T *> {
297 typedef
298 typename std::conditional<std::is_fundamental<T>::value,
299 FundamentalPointerTag, PointerTag>::type type;
300 };
301 template <class T> struct serializer_tag<T &> {
302 typedef typename std::conditional<std::is_fundamental<T>::value,
303 FundamentalReferenceTag, ReferenceTag>::type
304 type;
305 };
306
307 /// Deserializes data from a buffer. It is used to deserialize function indices
308 /// to replay, their arguments and return values.
309 ///
310 /// Fundamental types and strings are read by value. Objects are read by their
311 /// index, which get translated by the IndexToObject mapping maintained in
312 /// this class.
313 ///
314 /// Additional bookkeeping with regards to the IndexToObject is required to
315 /// deserialize objects. When a constructor is run or an object is returned by
316 /// value, we need to capture the object and add it to the index together with
317 /// its index. This is the job of HandleReplayResult(Void).
318 class Deserializer {
319 public:
320 Deserializer(llvm::StringRef buffer) : m_buffer(buffer) {}
321
322 /// Returns true when the buffer has unread data.
323 bool HasData(unsigned size) { return size <= m_buffer.size(); }
324
325 /// Deserialize and interpret value as T.
326 template <typename T> T Deserialize() {
327 T t = Read<T>(typename serializer_tag<T>::type());
328 #ifdef LLDB_REPRO_INSTR_TRACE
329 llvm::errs() << "Deserializing with " << LLVM_PRETTY_FUNCTION << " -> "
330 << stringify_args(t) << "\n";
331 #endif
332 return t;
333 }
334
335 template <typename T> const T &HandleReplayResult(const T &t) {
336 unsigned result = Deserialize<unsigned>();
337 if (is_trivially_serializable<T>::value)
338 return t;
339 // We need to make a copy as the original object might go out of scope.
340 return *m_index_to_object.AddObjectForIndex(result, new T(t));
341 }
342
343 /// Store the returned value in the index-to-object mapping.
344 template <typename T> T &HandleReplayResult(T &t) {
345 unsigned result = Deserialize<unsigned>();
346 if (is_trivially_serializable<T>::value)
347 return t;
348 // We need to make a copy as the original object might go out of scope.
349 return *m_index_to_object.AddObjectForIndex(result, new T(t));
350 }
351
352 /// Store the returned value in the index-to-object mapping.
353 template <typename T> T *HandleReplayResult(T *t) {
354 unsigned result = Deserialize<unsigned>();
355 if (is_trivially_serializable<T>::value)
356 return t;
357 return m_index_to_object.AddObjectForIndex(result, t);
358 }
359
360 /// All returned types are recorded, even when the function returns a void.
361 /// The latter requires special handling.
362 void HandleReplayResultVoid() {
363 unsigned result = Deserialize<unsigned>();
364 assert(result == 0);
365 (void)result;
366 }
367
368 std::vector<void *> GetAllObjects() const {
369 return m_index_to_object.GetAllObjects();
370 }
371
372 private:
373 template <typename T> T Read(ValueTag) {
374 assert(HasData(sizeof(T)));
375 T t;
376 std::memcpy(reinterpret_cast<char *>(&t), m_buffer.data(), sizeof(T));
377 m_buffer = m_buffer.drop_front(sizeof(T));
378 return t;
379 }
380
381 template <typename T> T Read(PointerTag) {
382 typedef typename std::remove_pointer<T>::type UnderlyingT;
383 return m_index_to_object.template GetObjectForIndex<UnderlyingT>(
384 Deserialize<unsigned>());
385 }
386
387 template <typename T> T Read(ReferenceTag) {
388 typedef typename std::remove_reference<T>::type UnderlyingT;
389 // If this is a reference to a fundamental type we just read its value.
390 return *m_index_to_object.template GetObjectForIndex<UnderlyingT>(
391 Deserialize<unsigned>());
392 }
393
394 /// This method is used to parse references to fundamental types. Because
395 /// they're not recorded in the object table we have serialized their value.
396 /// We read its value, allocate a copy on the heap, and return a pointer to
397 /// the copy.
398 template <typename T> T Read(FundamentalPointerTag) {
399 typedef typename std::remove_pointer<T>::type UnderlyingT;
400 return new UnderlyingT(Deserialize<UnderlyingT>());
401 }
402
403 /// This method is used to parse references to fundamental types. Because
404 /// they're not recorded in the object table we have serialized their value.
405 /// We read its value, allocate a copy on the heap, and return a reference to
406 /// the copy.
407 template <typename T> T Read(FundamentalReferenceTag) {
408 // If this is a reference to a fundamental type we just read its value.
409 typedef typename std::remove_reference<T>::type UnderlyingT;
410 return *(new UnderlyingT(Deserialize<UnderlyingT>()));
411 }
412
413 /// Mapping of indices to objects.
414 IndexToObject m_index_to_object;
415
416 /// Buffer containing the serialized data.
417 llvm::StringRef m_buffer;
418 };
419
420 /// Partial specialization for C-style strings. We read the string value
421 /// instead of treating it as pointer.
422 template <> const char *Deserializer::Deserialize<const char *>();
423 template <> const char **Deserializer::Deserialize<const char **>();
424 template <> const uint8_t *Deserializer::Deserialize<const uint8_t *>();
425 template <> const void *Deserializer::Deserialize<const void *>();
426 template <> char *Deserializer::Deserialize<char *>();
427 template <> void *Deserializer::Deserialize<void *>();
428
429 /// Helpers to auto-synthesize function replay code. It deserializes the replay
430 /// function's arguments one by one and finally calls the corresponding
431 /// function.
432 template <typename... Remaining> struct DeserializationHelper;
433
434 template <typename Head, typename... Tail>
435 struct DeserializationHelper<Head, Tail...> {
436 template <typename Result, typename... Deserialized> struct deserialized {
437 static Result doit(Deserializer &deserializer,
438 Result (*f)(Deserialized..., Head, Tail...),
439 Deserialized... d) {
440 return DeserializationHelper<Tail...>::
441 template deserialized<Result, Deserialized..., Head>::doit(
442 deserializer, f, d..., deserializer.Deserialize<Head>());
443 }
444 };
445 };
446
447 template <> struct DeserializationHelper<> {
448 template <typename Result, typename... Deserialized> struct deserialized {
449 static Result doit(Deserializer &deserializer, Result (*f)(Deserialized...),
450 Deserialized... d) {
451 return f(d...);
452 }
453 };
454 };
455
456 /// The replayer interface.
457 struct Replayer {
458 virtual ~Replayer() {}
459 virtual void operator()(Deserializer &deserializer) const = 0;
460 };
461
462 /// The default replayer deserializes the arguments and calls the function.
463 template <typename Signature> struct DefaultReplayer;
464 template <typename Result, typename... Args>
465 struct DefaultReplayer<Result(Args...)> : public Replayer {
466 DefaultReplayer(Result (*f)(Args...)) : Replayer(), f(f) {}
467
468 void operator()(Deserializer &deserializer) const override {
469 Replay(deserializer);
470 }
471
472 Result Replay(Deserializer &deserializer) const {
473 return deserializer.HandleReplayResult(
474 DeserializationHelper<Args...>::template deserialized<Result>::doit(
475 deserializer, f));
476 }
477
478 Result (*f)(Args...);
479 };
480
481 /// Partial specialization for function returning a void type. It ignores the
482 /// (absent) return value.
483 template <typename... Args>
484 struct DefaultReplayer<void(Args...)> : public Replayer {
485 DefaultReplayer(void (*f)(Args...)) : Replayer(), f(f) {}
486
487 void operator()(Deserializer &deserializer) const override {
488 Replay(deserializer);
489 }
490
491 void Replay(Deserializer &deserializer) const {
492 DeserializationHelper<Args...>::template deserialized<void>::doit(
493 deserializer, f);
494 deserializer.HandleReplayResultVoid();
495 }
496
497 void (*f)(Args...);
498 };
499
500 /// The registry contains a unique mapping between functions and their ID. The
501 /// IDs can be serialized and deserialized to replay a function. Functions need
502 /// to be registered with the registry for this to work.
503 class Registry {
504 private:
505 struct SignatureStr {
506 SignatureStr(llvm::StringRef result = {}, llvm::StringRef scope = {},
507 llvm::StringRef name = {}, llvm::StringRef args = {})
508 : result(result), scope(scope), name(name), args(args) {}
509
510 std::string ToString() const;
511
512 llvm::StringRef result;
513 llvm::StringRef scope;
514 llvm::StringRef name;
515 llvm::StringRef args;
516 };
517
518 public:
519 Registry() = default;
520 virtual ~Registry() = default;
521
522 /// Register a default replayer for a function.
523 template <typename Signature>
524 void Register(Signature *f, llvm::StringRef result = {},
525 llvm::StringRef scope = {}, llvm::StringRef name = {},
526 llvm::StringRef args = {}) {
527 DoRegister(uintptr_t(f), std::make_unique<DefaultReplayer<Signature>>(f),
528 SignatureStr(result, scope, name, args));
529 }
530
531 /// Register a replayer that invokes a custom function with the same
532 /// signature as the replayed function.
533 template <typename Signature>
534 void Register(Signature *f, Signature *g, llvm::StringRef result = {},
535 llvm::StringRef scope = {}, llvm::StringRef name = {},
536 llvm::StringRef args = {}) {
537 DoRegister(uintptr_t(f), std::make_unique<DefaultReplayer<Signature>>(g),
538 SignatureStr(result, scope, name, args));
539 }
540
541 /// Replay functions from a file.
542 bool Replay(const FileSpec &file);
543
544 /// Replay functions from a buffer.
545 bool Replay(llvm::StringRef buffer);
546
547 /// Replay functions from a deserializer.
548 bool Replay(Deserializer &deserializer);
549
550 /// Returns the ID for a given function address.
551 unsigned GetID(uintptr_t addr);
552
553 /// Get the replayer matching the given ID.
554 Replayer *GetReplayer(unsigned id);
555
556 std::string GetSignature(unsigned id);
557
558 void CheckID(unsigned expected, unsigned actual);
559
560 protected:
561 /// Register the given replayer for a function (and the ID mapping).
562 void DoRegister(uintptr_t RunID, std::unique_ptr<Replayer> replayer,
563 SignatureStr signature);
564
565 private:
566 /// Mapping of function addresses to replayers and their ID.
567 std::map<uintptr_t, std::pair<std::unique_ptr<Replayer>, unsigned>>
568 m_replayers;
569
570 /// Mapping of IDs to replayer instances.
571 std::map<unsigned, std::pair<Replayer *, SignatureStr>> m_ids;
572 };
573
574 /// Maps an object to an index for serialization. Indices are unique and
575 /// incremented for every new object.
576 ///
577 /// Indices start at 1 in order to differentiate with an invalid index (0) in
578 /// the serialized buffer.
579 class ObjectToIndex {
580 public:
581 template <typename T> unsigned GetIndexForObject(T *t) {
582 return GetIndexForObjectImpl(static_cast<const void *>(t));
583 }
584
585 private:
586 unsigned GetIndexForObjectImpl(const void *object);
587
588 llvm::DenseMap<const void *, unsigned> m_mapping;
589 };
590
591 /// Serializes functions, their arguments and their return type to a stream.
592 class Serializer {
593 public:
594 Serializer(llvm::raw_ostream &stream = llvm::outs()) : m_stream(stream) {}
595
596 /// Recursively serialize all the given arguments.
597 template <typename Head, typename... Tail>
598 void SerializeAll(const Head &head, const Tail &... tail) {
599 Serialize(head);
600 SerializeAll(tail...);
601 }
602
603 void SerializeAll() { m_stream.flush(); }
604
605 private:
606 /// Serialize pointers. We need to differentiate between pointers to
607 /// fundamental types (in which case we serialize its value) and pointer to
608 /// objects (in which case we serialize their index).
609 template <typename T> void Serialize(T *t) {
610 #ifdef LLDB_REPRO_INSTR_TRACE
611 this_thread_id() << "Serializing with " << LLVM_PRETTY_FUNCTION << " -> "
612 << stringify_args(t) << "\n";
613 #endif
614 if (std::is_fundamental<T>::value) {
615 Serialize(*t);
616 } else {
617 unsigned idx = m_tracker.GetIndexForObject(t);
618 Serialize(idx);
619 }
620 }
621
622 /// Serialize references. We need to differentiate between references to
623 /// fundamental types (in which case we serialize its value) and references
624 /// to objects (in which case we serialize their index).
625 template <typename T> void Serialize(T &t) {
626 #ifdef LLDB_REPRO_INSTR_TRACE
627 this_thread_id() << "Serializing with " << LLVM_PRETTY_FUNCTION << " -> "
628 << stringify_args(t) << "\n";
629 #endif
630 if (is_trivially_serializable<T>::value) {
631 m_stream.write(reinterpret_cast<const char *>(&t), sizeof(T));
632 } else {
633 unsigned idx = m_tracker.GetIndexForObject(&t);
634 Serialize(idx);
635 }
636 }
637
638 void Serialize(const void *v) {
639 // FIXME: Support void*
640 }
641
642 void Serialize(void *v) {
643 // FIXME: Support void*
644 }
645
646 void Serialize(const char *t) {
647 #ifdef LLDB_REPRO_INSTR_TRACE
648 this_thread_id() << "Serializing with " << LLVM_PRETTY_FUNCTION << " -> "
649 << stringify_args(t) << "\n";
650 #endif
651 const size_t size = t ? strlen(t) : std::numeric_limits<size_t>::max();
652 Serialize(size);
653 if (t) {
654 m_stream << t;
655 m_stream.write(0x0);
656 }
657 }
658
659 void Serialize(const char **t) {
660 size_t size = 0;
661 if (!t) {
662 Serialize(size);
663 return;
664 }
665
666 // Compute the size of the array.
667 const char *const *temp = t;
668 while (*temp++)
669 size++;
670 Serialize(size);
671
672 // Serialize the content of the array.
673 while (*t)
674 Serialize(*t++);
675 }
676
677 /// Serialization stream.
678 llvm::raw_ostream &m_stream;
679
680 /// Mapping of objects to indices.
681 ObjectToIndex m_tracker;
682 }; // namespace repro
683
684 class InstrumentationData {
685 public:
686 Serializer *GetSerializer() { return m_serializer; }
687 Deserializer *GetDeserializer() { return m_deserializer; }
688 Registry &GetRegistry() { return *m_registry; }
689
690 operator bool() {
691 return (m_serializer != nullptr || m_deserializer != nullptr) &&
692 m_registry != nullptr;
693 }
694
695 static void Initialize(Serializer &serializer, Registry ®istry);
696 static void Initialize(Deserializer &serializer, Registry ®istry);
697 static InstrumentationData &Instance();
698
699 protected:
700 friend llvm::optional_detail::OptionalStorage<InstrumentationData, true>;
701 friend llvm::Optional<InstrumentationData>;
702
703 InstrumentationData()
704 : m_serializer(nullptr), m_deserializer(nullptr), m_registry(nullptr) {}
705 InstrumentationData(Serializer &serializer, Registry ®istry)
706 : m_serializer(&serializer), m_deserializer(nullptr),
707 m_registry(®istry) {}
708 InstrumentationData(Deserializer &deserializer, Registry ®istry)
709 : m_serializer(nullptr), m_deserializer(&deserializer),
710 m_registry(®istry) {}
711
712 private:
713 static llvm::Optional<InstrumentationData> &InstanceImpl();
714
715 Serializer *m_serializer;
716 Deserializer *m_deserializer;
717 Registry *m_registry;
718 };
719
720 struct EmptyArg {};
721
722 /// RAII object that records function invocations and their return value.
723 ///
724 /// API calls are only captured when the API boundary is crossed. Once we're in
725 /// the API layer, and another API function is called, it doesn't need to be
726 /// recorded.
727 ///
728 /// When a call is recored, its result is always recorded as well, even if the
729 /// function returns a void. For functions that return by value, RecordResult
730 /// should be used. Otherwise a sentinel value (0) will be serialized.
731 ///
732 /// Because of the functional overlap between logging and recording API calls,
733 /// this class is also used for logging.
734 class Recorder {
735 public:
736 Recorder();
737 Recorder(llvm::StringRef pretty_func, std::string &&pretty_args = {});
738 ~Recorder();
739
740 /// Records a single function call.
741 template <typename Result, typename... FArgs, typename... RArgs>
742 void Record(Serializer &serializer, Registry ®istry, Result (*f)(FArgs...),
743 const RArgs &... args) {
744 m_serializer = &serializer;
745 if (!ShouldCapture())
746 return;
747
748 unsigned id = registry.GetID(uintptr_t(f));
749
750 #ifdef LLDB_REPRO_INSTR_TRACE
751 Log(id);
752 #endif
753
754 serializer.SerializeAll(id);
755 serializer.SerializeAll(args...);
756
757 if (std::is_class<typename std::remove_pointer<
758 typename std::remove_reference<Result>::type>::type>::value) {
759 m_result_recorded = false;
760 } else {
761 serializer.SerializeAll(0);
762 m_result_recorded = true;
763 }
764 }
765
766 /// Records a single function call.
767 template <typename... Args>
768 void Record(Serializer &serializer, Registry ®istry, void (*f)(Args...),
769 const Args &... args) {
770 m_serializer = &serializer;
771 if (!ShouldCapture())
772 return;
773
774 unsigned id = registry.GetID(uintptr_t(f));
775
776 #ifdef LLDB_REPRO_INSTR_TRACE
777 Log(id);
778 #endif
779
780 serializer.SerializeAll(id);
781 serializer.SerializeAll(args...);
782
783 // Record result.
784 serializer.SerializeAll(0);
785 m_result_recorded = true;
786 }
787
788 /// Specializations for the no-argument methods. These are passed an empty
789 /// dummy argument so the same variadic macro can be used. These methods
790 /// strip the arguments before forwarding them.
791 template <typename Result>
792 void Record(Serializer &serializer, Registry ®istry, Result (*f)(),
793 const EmptyArg &arg) {
794 Record(serializer, registry, f);
795 }
796
797 /// Record the result of a function call.
798 template <typename Result>
799 Result RecordResult(Result &&r, bool update_boundary) {
800 // When recording the result from the LLDB_RECORD_RESULT macro, we need to
801 // update the boundary so we capture the copy constructor. However, when
802 // called to record the this pointer of the (copy) constructor, the
803 // boundary should not be toggled, because it is called from the
804 // LLDB_RECORD_CONSTRUCTOR macro, which might be followed by other API
805 // calls.
806 if (update_boundary)
807 UpdateBoundary();
808 if (m_serializer && ShouldCapture()) {
809 assert(!m_result_recorded);
810 m_serializer->SerializeAll(r);
811 m_result_recorded = true;
812 }
813 return std::forward<Result>(r);
814 }
815
816 template <typename Result, typename T>
817 Result Replay(Deserializer &deserializer, Registry ®istry, uintptr_t addr,
818 bool update_boundary) {
819 unsigned actual_id = registry.GetID(addr);
820 unsigned id = deserializer.Deserialize<unsigned>();
821 registry.CheckID(id, actual_id);
822 return ReplayResult<Result>(
823 static_cast<DefaultReplayer<T> *>(registry.GetReplayer(id))
824 ->Replay(deserializer),
825 update_boundary);
826 }
827
828 void Replay(Deserializer &deserializer, Registry ®istry, uintptr_t addr) {
829 unsigned actual_id = registry.GetID(addr);
830 unsigned id = deserializer.Deserialize<unsigned>();
831 registry.CheckID(id, actual_id);
832 registry.GetReplayer(id)->operator()(deserializer);
833 }
834
835 template <typename Result>
836 Result ReplayResult(Result &&r, bool update_boundary) {
837 if (update_boundary)
838 UpdateBoundary();
839 return std::forward<Result>(r);
840 }
841
842 bool ShouldCapture() { return m_local_boundary; }
843
844 /// Mark the current thread as a private thread and pretend that everything
845 /// on this thread is behind happening behind the API boundary.
846 static void PrivateThread() { g_global_boundary = true; }
847
848 private:
849 template <typename T> friend struct replay;
850 void UpdateBoundary() {
851 if (m_local_boundary)
852 g_global_boundary = false;
853 }
854
855 #ifdef LLDB_REPRO_INSTR_TRACE
856 void Log(unsigned id) {
857 this_thread_id() << "Recording " << id << ": " << m_pretty_func << " ("
858 << m_pretty_args << ")\n";
859 }
860 #endif
861
862 Serializer *m_serializer;
863
864 /// Pretty function for logging.
865 llvm::StringRef m_pretty_func;
866 std::string m_pretty_args;
867
868 /// Whether this function call was the one crossing the API boundary.
869 bool m_local_boundary;
870
871 /// Whether the return value was recorded explicitly.
872 bool m_result_recorded;
873
874 /// Whether we're currently across the API boundary.
875 static thread_local bool g_global_boundary;
876 };
877
878 /// To be used as the "Runtime ID" of a constructor. It also invokes the
879 /// constructor when called.
880 template <typename Signature> struct construct;
881 template <typename Class, typename... Args> struct construct<Class(Args...)> {
882 static Class *handle(lldb_private::repro::InstrumentationData data,
883 lldb_private::repro::Recorder &recorder, Class *c,
884 const EmptyArg &) {
885 return handle(data, recorder, c);
886 }
887
888 static Class *handle(lldb_private::repro::InstrumentationData data,
889 lldb_private::repro::Recorder &recorder, Class *c,
890 Args... args) {
891 if (!data)
892 return nullptr;
893
894 if (Serializer *serializer = data.GetSerializer()) {
895 recorder.Record(*serializer, data.GetRegistry(), &record, args...);
896 recorder.RecordResult(c, false);
897 } else if (Deserializer *deserializer = data.GetDeserializer()) {
898 if (recorder.ShouldCapture()) {
899 replay(recorder, *deserializer, data.GetRegistry());
900 }
901 }
902
903 return nullptr;
904 }
905
906 static Class *record(Args... args) { return new Class(args...); }
907
908 static Class *replay(Recorder &recorder, Deserializer &deserializer,
909 Registry ®istry) {
910 return recorder.Replay<Class *, Class *(Args...)>(
911 deserializer, registry, uintptr_t(&record), false);
912 }
913 };
914
915 /// To be used as the "Runtime ID" of a member function. It also invokes the
916 /// member function when called.
917 template <typename Signature> struct invoke;
918 template <typename Result, typename Class, typename... Args>
919 struct invoke<Result (Class::*)(Args...)> {
920 template <Result (Class::*m)(Args...)> struct method {
921 static Result record(Class *c, Args... args) { return (c->*m)(args...); }
922
923 static Result replay(Recorder &recorder, Deserializer &deserializer,
924 Registry ®istry) {
925 return recorder.Replay<Result, Result(Class *, Args...)>(
926 deserializer, registry, uintptr_t(&record), true);
927 }
928 };
929 };
930
931 template <typename Class, typename... Args>
932 struct invoke<void (Class::*)(Args...)> {
933 template <void (Class::*m)(Args...)> struct method {
934 static void record(Class *c, Args... args) { (c->*m)(args...); }
935 static void replay(Recorder &recorder, Deserializer &deserializer,
936 Registry ®istry) {
937 recorder.Replay(deserializer, registry, uintptr_t(&record));
938 }
939 };
940 };
941
942 template <typename Result, typename Class, typename... Args>
943 struct invoke<Result (Class::*)(Args...) const> {
944 template <Result (Class::*m)(Args...) const> struct method {
945 static Result record(Class *c, Args... args) { return (c->*m)(args...); }
946 static Result replay(Recorder &recorder, Deserializer &deserializer,
947 Registry ®istry) {
948 return recorder.Replay<Result, Result(Class *, Args...)>(
949 deserializer, registry, uintptr_t(&record), true);
950 }
951 };
952 };
953
954 template <typename Class, typename... Args>
955 struct invoke<void (Class::*)(Args...) const> {
956 template <void (Class::*m)(Args...) const> struct method {
957 static void record(Class *c, Args... args) { return (c->*m)(args...); }
958 static void replay(Recorder &recorder, Deserializer &deserializer,
959 Registry ®istry) {
960 recorder.Replay(deserializer, registry, uintptr_t(&record));
961 }
962 };
963 };
964
965 template <typename Signature> struct replay;
966
967 template <typename Result, typename Class, typename... Args>
968 struct replay<Result (Class::*)(Args...)> {
969 template <Result (Class::*m)(Args...)> struct method {};
970 };
971
972 template <typename Result, typename... Args>
973 struct invoke<Result (*)(Args...)> {
974 template <Result (*m)(Args...)> struct method {
975 static Result record(Args... args) { return (*m)(args...); }
976 static Result replay(Recorder &recorder, Deserializer &deserializer,
977 Registry ®istry) {
978 return recorder.Replay<Result, Result(Args...)>(deserializer, registry,
979 uintptr_t(&record), true);
980 }
981 };
982 };
983
984 template <typename... Args> struct invoke<void (*)(Args...)> {
985 template <void (*m)(Args...)> struct method {
986 static void record(Args... args) { return (*m)(args...); }
987 static void replay(Recorder &recorder, Deserializer &deserializer,
988 Registry ®istry) {
989 recorder.Replay(deserializer, registry, uintptr_t(&record));
990 }
991 };
992 };
993
994 /// Special handling for functions returning strings as (char*, size_t).
995 /// {
996
997 /// For inline replay, we ignore the arguments and use the ones from the
998 /// serializer instead. This doesn't work for methods that use a char* and a
999 /// size to return a string. For one these functions have a custom replayer to
1000 /// prevent override the input buffer. Furthermore, the template-generated
1001 /// deserialization is not easy to hook into.
1002 ///
1003 /// The specializations below hand-implement the serialization logic for the
1004 /// inline replay. Instead of using the function from the registry, it uses the
1005 /// one passed into the macro.
1006 template <typename Signature> struct invoke_char_ptr;
1007 template <typename Result, typename Class, typename... Args>
1008 struct invoke_char_ptr<Result (Class::*)(Args...) const> {
1009 template <Result (Class::*m)(Args...) const> struct method {
1010 static Result record(Class *c, char *s, size_t l) {
1011 char *buffer = reinterpret_cast<char *>(calloc(l, sizeof(char)));
1012 return (c->*m)(buffer, l);
1013 }
1014
1015 static Result replay(Recorder &recorder, Deserializer &deserializer,
1016 Registry ®istry, char *str) {
1017 deserializer.Deserialize<unsigned>();
1018 Class *c = deserializer.Deserialize<Class *>();
1019 deserializer.Deserialize<const char *>();
1020 size_t l = deserializer.Deserialize<size_t>();
1021 return recorder.ReplayResult(
1022 std::move(deserializer.HandleReplayResult((c->*m)(str, l))), true);
1023 }
1024 };
1025 };
1026
1027 template <typename Signature> struct invoke_char_ptr;
1028 template <typename Result, typename Class, typename... Args>
1029 struct invoke_char_ptr<Result (Class::*)(Args...)> {
1030 template <Result (Class::*m)(Args...)> struct method {
1031 static Result record(Class *c, char *s, size_t l) {
1032 char *buffer = reinterpret_cast<char *>(calloc(l, sizeof(char)));
1033 return (c->*m)(buffer, l);
1034 }
1035
1036 static Result replay(Recorder &recorder, Deserializer &deserializer,
1037 Registry ®istry, char *str) {
1038 deserializer.Deserialize<unsigned>();
1039 Class *c = deserializer.Deserialize<Class *>();
1040 deserializer.Deserialize<const char *>();
1041 size_t l = deserializer.Deserialize<size_t>();
1042 return recorder.ReplayResult(
1043 std::move(deserializer.HandleReplayResult((c->*m)(str, l))), true);
1044 }
1045 };
1046 };
1047
1048 template <typename Result, typename... Args>
1049 struct invoke_char_ptr<Result (*)(Args...)> {
1050 template <Result (*m)(Args...)> struct method {
1051 static Result record(char *s, size_t l) {
1052 char *buffer = reinterpret_cast<char *>(calloc(l, sizeof(char)));
1053 return (*m)(buffer, l);
1054 }
1055
1056 static Result replay(Recorder &recorder, Deserializer &deserializer,
1057 Registry ®istry, char *str) {
1058 deserializer.Deserialize<unsigned>();
1059 deserializer.Deserialize<const char *>();
1060 size_t l = deserializer.Deserialize<size_t>();
1061 return recorder.ReplayResult(
1062 std::move(deserializer.HandleReplayResult((*m)(str, l))), true);
1063 }
1064 };
1065 };
1066 /// }
1067
1068 } // namespace repro
1069 } // namespace lldb_private
1070
1071 #endif // LLDB_UTILITY_REPRODUCERINSTRUMENTATION_H
1072