summaryrefslogtreecommitdiffstats
path: root/js/src/vm/RegExpShared.h
blob: 07f57d1e7a750fb265627f5d9df351f5b01453be (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*-
 * vim: set ts=8 sts=2 et sw=2 tw=80:
 * This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

/**
 * The compiled representation of a RegExp, potentially shared among RegExp
 * instances created during separate evaluations of a single RegExp literal in
 * source code.
 */

#ifndef vm_RegExpShared_h
#define vm_RegExpShared_h

#include "mozilla/Assertions.h"
#include "mozilla/MemoryReporting.h"

#include "gc/Barrier.h"
#include "gc/Policy.h"
#include "gc/SweepingAPI.h"
#include "gc/ZoneAllocator.h"
#include "irregexp/RegExpTypes.h"
#include "jit/JitCode.h"
#include "jit/JitOptions.h"
#include "js/AllocPolicy.h"
#include "js/RegExpFlags.h"  // JS::RegExpFlag, JS::RegExpFlags
#include "js/UbiNode.h"
#include "js/Vector.h"
#include "vm/ArrayObject.h"

namespace js {

class ArrayObject;
class PlainObject;
class RegExpRealm;
class RegExpShared;
class RegExpStatics;
class VectorMatchPairs;

using RootedRegExpShared = JS::Rooted<RegExpShared*>;
using HandleRegExpShared = JS::Handle<RegExpShared*>;
using MutableHandleRegExpShared = JS::MutableHandle<RegExpShared*>;

enum class RegExpRunStatus : int32_t {
  Error = -1,
  Success = 1,
  Success_NotFound = 0,
};

inline bool IsNativeRegExpEnabled() {
  return jit::HasJitBackend() && jit::JitOptions.nativeRegExp;
}

/*
 * A RegExpShared is the compiled representation of a regexp. A RegExpShared is
 * potentially pointed to by multiple RegExpObjects. Additionally, C++ code may
 * have pointers to RegExpShareds on the stack. The RegExpShareds are kept in a
 * table so that they can be reused when compiling the same regex string.
 *
 * To save memory, a RegExpShared is not created for a RegExpObject until it is
 * needed for execution. When a RegExpShared needs to be created, it is looked
 * up in a per-compartment table to allow reuse between objects.
 *
 * During a GC, RegExpShared instances are marked and swept like GC things.
 * Usually, RegExpObjects clear their pointers to their RegExpShareds rather
 * than explicitly tracing them, so that the RegExpShared and any jitcode can
 * be reclaimed quicker. However, the RegExpShareds are traced through by
 * objects when we are preserving jitcode in their zone, to avoid the same
 * recompilation inefficiencies as normal Ion and baseline compilation.
 */
class RegExpShared
    : public gc::CellWithTenuredGCPointer<gc::TenuredCell, JSAtom> {
  friend class js::gc::CellAllocator;

 public:
  enum class Kind : uint32_t { Unparsed, Atom, RegExp };
  enum class CodeKind { Bytecode, Jitcode, Any };

  using ByteCode = js::irregexp::ByteArrayData;
  using JitCodeTable = js::irregexp::ByteArray;
  using JitCodeTables = Vector<JitCodeTable, 0, SystemAllocPolicy>;

 private:
  friend class RegExpStatics;
  friend class RegExpZone;

  struct RegExpCompilation {
    HeapPtr<jit::JitCode*> jitCode;
    ByteCode* byteCode = nullptr;

    bool compiled(CodeKind kind = CodeKind::Any) const {
      switch (kind) {
        case CodeKind::Bytecode:
          return !!byteCode;
        case CodeKind::Jitcode:
          return !!jitCode;
        case CodeKind::Any:
          return !!byteCode || !!jitCode;
      }
      MOZ_CRASH("Unreachable");
    }

    size_t byteCodeLength() const {
      MOZ_ASSERT(byteCode);
      return byteCode->length();
    }
  };

 public:
  /* Source to the RegExp, for lazy compilation. Stored in the cell header. */
  JSAtom* getSource() const { return headerPtr(); }

 private:
  RegExpCompilation compilationArray[2];

  uint32_t pairCount_;
  JS::RegExpFlags flags;

  RegExpShared::Kind kind_ = Kind::Unparsed;
  GCPtr<JSAtom*> patternAtom_;
  uint32_t maxRegisters_ = 0;
  uint32_t ticks_ = 0;

  uint32_t numNamedCaptures_ = {};
  uint32_t* namedCaptureIndices_ = {};
  GCPtr<PlainObject*> groupsTemplate_ = {};

  static int CompilationIndex(bool latin1) { return latin1 ? 0 : 1; }

  // Tables referenced by JIT code.
  JitCodeTables tables;

  /* Internal functions. */
  RegExpShared(JSAtom* source, JS::RegExpFlags flags);

  const RegExpCompilation& compilation(bool latin1) const {
    return compilationArray[CompilationIndex(latin1)];
  }

  RegExpCompilation& compilation(bool latin1) {
    return compilationArray[CompilationIndex(latin1)];
  }

 public:
  ~RegExpShared() = delete;

  static bool compileIfNecessary(JSContext* cx, MutableHandleRegExpShared res,
                                 Handle<JSLinearString*> input, CodeKind code);

  static RegExpRunStatus executeAtom(MutableHandleRegExpShared re,
                                     Handle<JSLinearString*> input,
                                     size_t start, VectorMatchPairs* matches);

  // Execute this RegExp on input starting from searchIndex, filling in matches.
  static RegExpRunStatus execute(JSContext* cx, MutableHandleRegExpShared res,
                                 Handle<JSLinearString*> input,
                                 size_t searchIndex, VectorMatchPairs* matches);

  // Register a table with this RegExpShared, and take ownership.
  bool addTable(JitCodeTable table) { return tables.append(std::move(table)); }

  /* Accessors */

  size_t pairCount() const {
    MOZ_ASSERT(kind() != Kind::Unparsed);
    return pairCount_;
  }

  RegExpShared::Kind kind() const { return kind_; }

  // Use simple string matching for this regexp.
  void useAtomMatch(Handle<JSAtom*> pattern);

  // Use the regular expression engine for this regexp.
  void useRegExpMatch(size_t parenCount);

  static void InitializeNamedCaptures(JSContext* cx, HandleRegExpShared re,
                                      uint32_t numNamedCaptures,
                                      Handle<PlainObject*> templateObject,
                                      uint32_t* captureIndices);
  PlainObject* getGroupsTemplate() { return groupsTemplate_; }

  void tierUpTick();
  bool markedForTierUp() const;

  void setByteCode(ByteCode* code, bool latin1) {
    compilation(latin1).byteCode = code;
  }
  ByteCode* getByteCode(bool latin1) const {
    return compilation(latin1).byteCode;
  }
  void setJitCode(jit::JitCode* code, bool latin1) {
    compilation(latin1).jitCode = code;
  }
  jit::JitCode* getJitCode(bool latin1) const {
    return compilation(latin1).jitCode;
  }
  uint32_t getMaxRegisters() const { return maxRegisters_; }
  void updateMaxRegisters(uint32_t numRegisters) {
    maxRegisters_ = std::max(maxRegisters_, numRegisters);
  }

  uint32_t numNamedCaptures() const { return numNamedCaptures_; }
  int32_t getNamedCaptureIndex(uint32_t idx) const {
    MOZ_ASSERT(idx < numNamedCaptures());
    MOZ_ASSERT(namedCaptureIndices_);
    return namedCaptureIndices_[idx];
  }

  JSAtom* patternAtom() const { return patternAtom_; }

  JS::RegExpFlags getFlags() const { return flags; }

  bool hasIndices() const { return flags.hasIndices(); }
  bool global() const { return flags.global(); }
  bool ignoreCase() const { return flags.ignoreCase(); }
  bool multiline() const { return flags.multiline(); }
  bool dotAll() const { return flags.dotAll(); }
  bool unicode() const { return flags.unicode(); }
  bool unicodeSets() const { return flags.unicodeSets(); }
  bool sticky() const { return flags.sticky(); }

  bool isCompiled(bool latin1, CodeKind codeKind = CodeKind::Any) const {
    return compilation(latin1).compiled(codeKind);
  }
  bool isCompiled() const { return isCompiled(true) || isCompiled(false); }

  void traceChildren(JSTracer* trc);
  void discardJitCode();
  void finalize(JS::GCContext* gcx);

  static size_t offsetOfSource() { return offsetOfHeaderPtr(); }

  static size_t offsetOfPatternAtom() {
    return offsetof(RegExpShared, patternAtom_);
  }

  static size_t offsetOfFlags() { return offsetof(RegExpShared, flags); }

  static size_t offsetOfPairCount() {
    return offsetof(RegExpShared, pairCount_);
  }

  static size_t offsetOfKind() { return offsetof(RegExpShared, kind_); }

  static size_t offsetOfJitCode(bool latin1) {
    return offsetof(RegExpShared, compilationArray) +
           (CompilationIndex(latin1) * sizeof(RegExpCompilation)) +
           offsetof(RegExpCompilation, jitCode);
  }

  static size_t offsetOfGroupsTemplate() {
    return offsetof(RegExpShared, groupsTemplate_);
  }

  size_t sizeOfExcludingThis(mozilla::MallocSizeOf mallocSizeOf);

 public:
  static const JS::TraceKind TraceKind = JS::TraceKind::RegExpShared;
};

class RegExpZone {
  struct Key {
    JSAtom* atom = nullptr;
    JS::RegExpFlags flags = JS::RegExpFlag::NoFlags;

    Key() = default;
    Key(JSAtom* atom, JS::RegExpFlags flags) : atom(atom), flags(flags) {}
    MOZ_IMPLICIT Key(const WeakHeapPtr<RegExpShared*>& shared)
        : atom(shared.unbarrieredGet()->getSource()),
          flags(shared.unbarrieredGet()->getFlags()) {}

    using Lookup = Key;
    static HashNumber hash(const Lookup& l) {
      HashNumber hash = DefaultHasher<JSAtom*>::hash(l.atom);
      return mozilla::AddToHash(hash, l.flags.value());
    }
    static bool match(Key l, Key r) {
      return l.atom == r.atom && l.flags == r.flags;
    }
  };

  /*
   * The set of all RegExpShareds in the zone. On every GC, every RegExpShared
   * that was not marked is deleted and removed from the set.
   */
  using Set = WeakCache<
      JS::GCHashSet<WeakHeapPtr<RegExpShared*>, Key, ZoneAllocPolicy>>;
  Set set_;

 public:
  explicit RegExpZone(Zone* zone);

  ~RegExpZone() { MOZ_ASSERT(set_.empty()); }

  bool empty() const { return set_.empty(); }

  RegExpShared* maybeGet(JSAtom* source, JS::RegExpFlags flags) const {
    Set::Ptr p = set_.lookup(Key(source, flags));
    return p ? *p : nullptr;
  }

  RegExpShared* get(JSContext* cx, Handle<JSAtom*> source,
                    JS::RegExpFlags flags);

#ifdef DEBUG
  void clear() { set_.clear(); }
#endif

  size_t sizeOfIncludingThis(mozilla::MallocSizeOf mallocSizeOf) const;
};

class RegExpRealm {
 public:
  enum ResultShapeKind { Normal, WithIndices, Indices, NumKinds };

  // Information about the last regular expression match. This is used by the
  // static RegExp properties such as RegExp.lastParen.
  UniquePtr<RegExpStatics> regExpStatics;

 private:
  /*
   * The shapes used for the result object of re.exec(), if there is a result.
   * These are used in CreateRegExpMatchResult. There are three shapes, each of
   * which is an ArrayObject shape with some additional properties. We decide
   * which to use based on the |hasIndices| (/d) flag.
   *
   *  Normal: Has |index|, |input|, and |groups| properties.
   *          Used for the result object if |hasIndices| is not set.
   *
   *  WithIndices: Has |index|, |input|, |groups|, and |indices| properties.
   *               Used for the result object if |hasIndices| is set.
   *
   *  Indices: Has a |groups| property. If |hasIndices| is set, used
   *           for the |.indices| property of the result object.
   */
  HeapPtr<SharedShape*> matchResultShapes_[ResultShapeKind::NumKinds];

  /*
   * The shape of RegExp.prototype object that satisfies following:
   *   * RegExp.prototype.flags getter is not modified
   *   * RegExp.prototype.global getter is not modified
   *   * RegExp.prototype.ignoreCase getter is not modified
   *   * RegExp.prototype.multiline getter is not modified
   *   * RegExp.prototype.dotAll getter is not modified
   *   * RegExp.prototype.sticky getter is not modified
   *   * RegExp.prototype.unicode getter is not modified
   *   * RegExp.prototype.exec is an own data property
   *   * RegExp.prototype[@@match] is an own data property
   *   * RegExp.prototype[@@search] is an own data property
   */
  HeapPtr<Shape*> optimizableRegExpPrototypeShape_;

  /*
   * The shape of RegExp instance that satisfies following:
   *   * lastProperty is lastIndex
   *   * prototype is RegExp.prototype
   */
  HeapPtr<Shape*> optimizableRegExpInstanceShape_;

  SharedShape* createMatchResultShape(JSContext* cx, ResultShapeKind kind);

 public:
  explicit RegExpRealm();

  void trace(JSTracer* trc);

  static const size_t MatchResultObjectIndexSlot = 0;
  static const size_t MatchResultObjectInputSlot = 1;
  static const size_t MatchResultObjectGroupsSlot = 2;
  static const size_t MatchResultObjectIndicesSlot = 3;

  // Number of used and allocated dynamic slots for a Normal match result
  // object. These values are checked in createMatchResultShape.
  static const size_t MatchResultObjectSlotSpan = 3;
  static const size_t MatchResultObjectNumDynamicSlots = 6;

  static const size_t IndicesGroupsSlot = 0;

  static size_t offsetOfMatchResultObjectIndexSlot() {
    return sizeof(Value) * MatchResultObjectIndexSlot;
  }
  static size_t offsetOfMatchResultObjectInputSlot() {
    return sizeof(Value) * MatchResultObjectInputSlot;
  }
  static size_t offsetOfMatchResultObjectGroupsSlot() {
    return sizeof(Value) * MatchResultObjectGroupsSlot;
  }
  static size_t offsetOfMatchResultObjectIndicesSlot() {
    return sizeof(Value) * MatchResultObjectIndicesSlot;
  }

  /* Get or create the shape used for the result of .exec(). */
  SharedShape* getOrCreateMatchResultShape(
      JSContext* cx, ResultShapeKind kind = ResultShapeKind::Normal) {
    if (matchResultShapes_[kind]) {
      return matchResultShapes_[kind];
    }
    return createMatchResultShape(cx, kind);
  }

  Shape* getOptimizableRegExpPrototypeShape() {
    return optimizableRegExpPrototypeShape_;
  }
  void setOptimizableRegExpPrototypeShape(Shape* shape) {
    optimizableRegExpPrototypeShape_ = shape;
  }
  Shape* getOptimizableRegExpInstanceShape() {
    return optimizableRegExpInstanceShape_;
  }
  void setOptimizableRegExpInstanceShape(Shape* shape) {
    optimizableRegExpInstanceShape_ = shape;
  }

  static constexpr size_t offsetOfOptimizableRegExpPrototypeShape() {
    return offsetof(RegExpRealm, optimizableRegExpPrototypeShape_);
  }
  static constexpr size_t offsetOfOptimizableRegExpInstanceShape() {
    return offsetof(RegExpRealm, optimizableRegExpInstanceShape_);
  }
  static constexpr size_t offsetOfRegExpStatics() {
    return offsetof(RegExpRealm, regExpStatics);
  }
  static constexpr size_t offsetOfNormalMatchResultShape() {
    static_assert(sizeof(HeapPtr<SharedShape*>) == sizeof(uintptr_t));
    return offsetof(RegExpRealm, matchResultShapes_) +
           ResultShapeKind::Normal * sizeof(uintptr_t);
  }
};

RegExpRunStatus ExecuteRegExpAtomRaw(RegExpShared* re, JSLinearString* input,
                                     size_t start, MatchPairs* matchPairs);

} /* namespace js */

namespace JS {
namespace ubi {

template <>
class Concrete<js::RegExpShared> : TracerConcrete<js::RegExpShared> {
 protected:
  explicit Concrete(js::RegExpShared* ptr)
      : TracerConcrete<js::RegExpShared>(ptr) {}

 public:
  static void construct(void* storage, js::RegExpShared* ptr) {
    new (storage) Concrete(ptr);
  }

  CoarseType coarseType() const final { return CoarseType::Other; }

  Size size(mozilla::MallocSizeOf mallocSizeOf) const override;

  const char16_t* typeName() const override { return concreteTypeName; }
  static const char16_t concreteTypeName[];
};

}  // namespace ubi
}  // namespace JS

#endif /* vm_RegExpShared_h */