This repository was archived by the owner on Jul 11, 2025. It is now read-only.
forked from phoboslab/JavaScriptCore-iOS
-
Notifications
You must be signed in to change notification settings - Fork 0
Expand file tree
/
Copy pathDFGArrayMode.h
More file actions
499 lines (424 loc) · 14.2 KB
/
DFGArrayMode.h
File metadata and controls
499 lines (424 loc) · 14.2 KB
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
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
/*
* Copyright (C) 2012, 2013 Apple Inc. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
* OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef DFGArrayMode_h
#define DFGArrayMode_h
#include <wtf/Platform.h>
#if ENABLE(DFG_JIT)
#include "ArrayProfile.h"
#include "DFGNodeFlags.h"
#include "SpeculatedType.h"
namespace JSC {
struct CodeOrigin;
namespace DFG {
class Graph;
struct AbstractValue;
struct Node;
// Use a namespace + enum instead of enum alone to avoid the namespace collision
// that would otherwise occur, since we say things like "Int8Array" and "JSArray"
// in lots of other places, to mean subtly different things.
namespace Array {
enum Action {
Read,
Write
};
enum Type {
SelectUsingPredictions, // Implies that we need predictions to decide. We will never get to the backend in this mode.
Unprofiled, // Implies that array profiling didn't see anything. But that could be because the operands didn't comply with basic type assumptions (base is cell, property is int). This either becomes Generic or ForceExit depending on value profiling.
ForceExit, // Implies that we have no idea how to execute this operation, so we should just give up.
Generic,
String,
Undecided,
Int32,
Double,
Contiguous,
ArrayStorage,
SlowPutArrayStorage,
Arguments,
Int8Array,
Int16Array,
Int32Array,
Uint8Array,
Uint8ClampedArray,
Uint16Array,
Uint32Array,
Float32Array,
Float64Array
};
enum Class {
NonArray, // Definitely some object that is not a JSArray.
OriginalNonArray, // Definitely some object that is not a JSArray, but that object has the original structure.
Array, // Definitely a JSArray, and may or may not have custom properties or have undergone some other bizarre transitions.
OriginalArray, // Definitely a JSArray, and still has one of the primordial JSArray structures for the global object that this code block (possibly inlined code block) belongs to.
PossiblyArray // Some object that may or may not be a JSArray.
};
enum Speculation {
SaneChain, // In bounds and the array prototype chain is still intact, i.e. loading a hole doesn't require special treatment.
InBounds, // In bounds and not loading a hole.
ToHole, // Potentially storing to a hole.
OutOfBounds // Out-of-bounds access and anything can happen.
};
enum Conversion {
AsIs,
Convert,
RageConvert
};
} // namespace Array
const char* arrayTypeToString(Array::Type);
const char* arrayClassToString(Array::Class);
const char* arraySpeculationToString(Array::Speculation);
const char* arrayConversionToString(Array::Conversion);
IndexingType toIndexingShape(Array::Type);
TypedArrayType toTypedArrayType(Array::Type);
Array::Type toArrayType(TypedArrayType);
bool permitsBoundsCheckLowering(Array::Type);
class ArrayMode {
public:
ArrayMode()
{
u.asBytes.type = Array::SelectUsingPredictions;
u.asBytes.arrayClass = Array::NonArray;
u.asBytes.speculation = Array::InBounds;
u.asBytes.conversion = Array::AsIs;
}
explicit ArrayMode(Array::Type type)
{
u.asBytes.type = type;
u.asBytes.arrayClass = Array::NonArray;
u.asBytes.speculation = Array::InBounds;
u.asBytes.conversion = Array::AsIs;
}
ArrayMode(Array::Type type, Array::Class arrayClass)
{
u.asBytes.type = type;
u.asBytes.arrayClass = arrayClass;
u.asBytes.speculation = Array::InBounds;
u.asBytes.conversion = Array::AsIs;
}
ArrayMode(Array::Type type, Array::Class arrayClass, Array::Speculation speculation, Array::Conversion conversion)
{
u.asBytes.type = type;
u.asBytes.arrayClass = arrayClass;
u.asBytes.speculation = speculation;
u.asBytes.conversion = conversion;
}
ArrayMode(Array::Type type, Array::Class arrayClass, Array::Conversion conversion)
{
u.asBytes.type = type;
u.asBytes.arrayClass = arrayClass;
u.asBytes.speculation = Array::InBounds;
u.asBytes.conversion = conversion;
}
Array::Type type() const { return static_cast<Array::Type>(u.asBytes.type); }
Array::Class arrayClass() const { return static_cast<Array::Class>(u.asBytes.arrayClass); }
Array::Speculation speculation() const { return static_cast<Array::Speculation>(u.asBytes.speculation); }
Array::Conversion conversion() const { return static_cast<Array::Conversion>(u.asBytes.conversion); }
unsigned asWord() const { return u.asWord; }
static ArrayMode fromWord(unsigned word)
{
return ArrayMode(word);
}
static ArrayMode fromObserved(const ConcurrentJITLocker&, ArrayProfile*, Array::Action, bool makeSafe);
ArrayMode withSpeculation(Array::Speculation speculation) const
{
return ArrayMode(type(), arrayClass(), speculation, conversion());
}
ArrayMode withProfile(const ConcurrentJITLocker& locker, ArrayProfile* profile, bool makeSafe) const
{
Array::Speculation mySpeculation;
Array::Class myArrayClass;
if (makeSafe)
mySpeculation = Array::OutOfBounds;
else if (profile->mayStoreToHole(locker))
mySpeculation = Array::ToHole;
else
mySpeculation = Array::InBounds;
if (isJSArray()) {
if (profile->usesOriginalArrayStructures(locker) && benefitsFromOriginalArray())
myArrayClass = Array::OriginalArray;
else
myArrayClass = Array::Array;
} else
myArrayClass = arrayClass();
return ArrayMode(type(), myArrayClass, mySpeculation, conversion());
}
ArrayMode withType(Array::Type type) const
{
return ArrayMode(type, arrayClass(), speculation(), conversion());
}
ArrayMode withConversion(Array::Conversion conversion) const
{
return ArrayMode(type(), arrayClass(), speculation(), conversion);
}
ArrayMode withTypeAndConversion(Array::Type type, Array::Conversion conversion) const
{
return ArrayMode(type, arrayClass(), speculation(), conversion);
}
ArrayMode refine(SpeculatedType base, SpeculatedType index, SpeculatedType value = SpecNone, NodeFlags = 0) const;
bool alreadyChecked(Graph&, Node*, AbstractValue&) const;
void dump(PrintStream&) const;
bool usesButterfly() const
{
switch (type()) {
case Array::Int32:
case Array::Double:
case Array::Contiguous:
case Array::ArrayStorage:
case Array::SlowPutArrayStorage:
return true;
default:
return false;
}
}
bool isJSArray() const
{
switch (arrayClass()) {
case Array::Array:
case Array::OriginalArray:
return true;
default:
return false;
}
}
bool isJSArrayWithOriginalStructure() const
{
return arrayClass() == Array::OriginalArray;
}
bool isSaneChain() const
{
return speculation() == Array::SaneChain;
}
bool isInBounds() const
{
switch (speculation()) {
case Array::SaneChain:
case Array::InBounds:
return true;
default:
return false;
}
}
bool mayStoreToHole() const
{
return !isInBounds();
}
bool isOutOfBounds() const
{
return speculation() == Array::OutOfBounds;
}
bool isSlowPut() const
{
return type() == Array::SlowPutArrayStorage;
}
bool canCSEStorage() const
{
switch (type()) {
case Array::SelectUsingPredictions:
case Array::Unprofiled:
case Array::ForceExit:
case Array::Generic:
case Array::Arguments:
return false;
default:
return true;
}
}
bool lengthNeedsStorage() const
{
switch (type()) {
case Array::Undecided:
case Array::Int32:
case Array::Double:
case Array::Contiguous:
case Array::ArrayStorage:
case Array::SlowPutArrayStorage:
return true;
default:
return false;
}
}
ArrayMode modeForPut() const
{
switch (type()) {
case Array::String:
return ArrayMode(Array::Generic);
#if USE(JSVALUE32_64)
case Array::Arguments:
return ArrayMode(Array::Generic);
#endif
default:
return *this;
}
}
bool isSpecific() const
{
switch (type()) {
case Array::SelectUsingPredictions:
case Array::Unprofiled:
case Array::ForceExit:
case Array::Generic:
case Array::Undecided:
return false;
default:
return true;
}
}
bool supportsLength() const
{
switch (type()) {
case Array::SelectUsingPredictions:
case Array::Unprofiled:
case Array::ForceExit:
case Array::Generic:
return false;
case Array::Int32:
case Array::Double:
case Array::Contiguous:
case Array::ArrayStorage:
case Array::SlowPutArrayStorage:
return isJSArray();
default:
return true;
}
}
bool permitsBoundsCheckLowering() const;
bool benefitsFromOriginalArray() const
{
switch (type()) {
case Array::Int32:
case Array::Double:
case Array::Contiguous:
case Array::ArrayStorage:
return true;
default:
return false;
}
}
// Returns 0 if this is not OriginalArray.
Structure* originalArrayStructure(Graph&, const CodeOrigin&) const;
Structure* originalArrayStructure(Graph&, Node*) const;
bool doesConversion() const
{
return conversion() != Array::AsIs;
}
bool structureWouldPassArrayModeFiltering(Structure* structure)
{
return arrayModesAlreadyChecked(arrayModeFromStructure(structure), arrayModesThatPassFiltering());
}
ArrayModes arrayModesThatPassFiltering() const
{
switch (type()) {
case Array::Generic:
return ALL_ARRAY_MODES;
case Array::Int32:
return arrayModesWithIndexingShape(Int32Shape);
case Array::Double:
return arrayModesWithIndexingShape(DoubleShape);
case Array::Contiguous:
return arrayModesWithIndexingShape(ContiguousShape);
case Array::ArrayStorage:
return arrayModesWithIndexingShape(ArrayStorageShape);
case Array::SlowPutArrayStorage:
return arrayModesWithIndexingShape(SlowPutArrayStorageShape);
default:
return asArrayModes(NonArray);
}
}
bool getIndexedPropertyStorageMayTriggerGC() const
{
return type() == Array::String;
}
IndexingType shapeMask() const
{
return toIndexingShape(type());
}
TypedArrayType typedArrayType() const
{
return toTypedArrayType(type());
}
bool operator==(const ArrayMode& other) const
{
return type() == other.type()
&& arrayClass() == other.arrayClass()
&& speculation() == other.speculation()
&& conversion() == other.conversion();
}
bool operator!=(const ArrayMode& other) const
{
return !(*this == other);
}
private:
explicit ArrayMode(unsigned word)
{
u.asWord = word;
}
ArrayModes arrayModesWithIndexingShape(IndexingType shape) const
{
switch (arrayClass()) {
case Array::NonArray:
case Array::OriginalNonArray:
return asArrayModes(shape);
case Array::Array:
case Array::OriginalArray:
return asArrayModes(shape | IsArray);
case Array::PossiblyArray:
return asArrayModes(shape) | asArrayModes(shape | IsArray);
default:
// This is only necessary for C++ compilers that don't understand enums.
return 0;
}
}
bool alreadyChecked(Graph&, Node*, AbstractValue&, IndexingType shape) const;
union {
struct {
uint8_t type;
uint8_t arrayClass;
uint8_t speculation;
uint8_t conversion;
} asBytes;
unsigned asWord;
} u;
};
static inline bool canCSEStorage(const ArrayMode& arrayMode)
{
return arrayMode.canCSEStorage();
}
static inline bool lengthNeedsStorage(const ArrayMode& arrayMode)
{
return arrayMode.lengthNeedsStorage();
}
static inline bool neverNeedsStorage(const ArrayMode&)
{
return false;
}
} } // namespace JSC::DFG
namespace WTF {
class PrintStream;
void printInternal(PrintStream&, JSC::DFG::Array::Type);
void printInternal(PrintStream&, JSC::DFG::Array::Class);
void printInternal(PrintStream&, JSC::DFG::Array::Speculation);
void printInternal(PrintStream&, JSC::DFG::Array::Conversion);
} // namespace WTF
#endif // ENABLE(DFG_JIT)
#endif // DFGArrayMode_h