-
Notifications
You must be signed in to change notification settings - Fork 54
/
UbiNodeCensus.cpp
1383 lines (1160 loc) · 41.4 KB
/
UbiNodeCensus.cpp
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
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
/* -*- 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/. */
#include "js/UbiNodeCensus.h"
#include "builtin/MapObject.h"
#include "js/CharacterEncoding.h"
#include "js/StableStringChars.h"
#include "util/Text.h"
#include "vm/JSContext.h"
#include "vm/Printer.h"
#include "vm/Realm.h"
#include "vm/JSObject-inl.h"
#include "vm/NativeObject-inl.h"
using namespace js;
namespace JS {
namespace ubi {
JS_PUBLIC_API void CountDeleter::operator()(CountBase* ptr) {
if (!ptr) {
return;
}
// Downcast to our true type and destruct, as guided by our CountType
// pointer.
ptr->destruct();
js_free(ptr);
}
/*** Count Types ************************************************************/
// The simplest type: just count everything.
class SimpleCount : public CountType {
struct Count : CountBase {
size_t totalBytes_;
explicit Count(SimpleCount& count) : CountBase(count), totalBytes_(0) {}
};
UniqueTwoByteChars label;
bool reportCount : 1;
bool reportBytes : 1;
public:
explicit SimpleCount(UniqueTwoByteChars& label, bool reportCount = true,
bool reportBytes = true)
: CountType(),
label(std::move(label)),
reportCount(reportCount),
reportBytes(reportBytes) {}
explicit SimpleCount()
: CountType(), label(nullptr), reportCount(true), reportBytes(true) {}
void destructCount(CountBase& countBase) override {
Count& count = static_cast<Count&>(countBase);
count.~Count();
}
CountBasePtr makeCount() override {
return CountBasePtr(js_new<Count>(*this));
}
void traceCount(CountBase& countBase, JSTracer* trc) override {}
bool count(CountBase& countBase, mozilla::MallocSizeOf mallocSizeOf,
const Node& node) override;
bool report(JSContext* cx, CountBase& countBase,
MutableHandleValue report) override;
};
bool SimpleCount::count(CountBase& countBase,
mozilla::MallocSizeOf mallocSizeOf, const Node& node) {
Count& count = static_cast<Count&>(countBase);
if (reportBytes) {
count.totalBytes_ += node.size(mallocSizeOf);
}
return true;
}
bool SimpleCount::report(JSContext* cx, CountBase& countBase,
MutableHandleValue report) {
Count& count = static_cast<Count&>(countBase);
RootedPlainObject obj(cx, NewBuiltinClassInstance<PlainObject>(cx));
if (!obj) {
return false;
}
RootedValue countValue(cx, NumberValue(count.total_));
if (reportCount &&
!DefineDataProperty(cx, obj, cx->names().count, countValue)) {
return false;
}
RootedValue bytesValue(cx, NumberValue(count.totalBytes_));
if (reportBytes &&
!DefineDataProperty(cx, obj, cx->names().bytes, bytesValue)) {
return false;
}
if (label) {
JSString* labelString = JS_NewUCStringCopyZ(cx, label.get());
if (!labelString) {
return false;
}
RootedValue labelValue(cx, StringValue(labelString));
if (!DefineDataProperty(cx, obj, cx->names().label, labelValue)) {
return false;
}
}
report.setObject(*obj);
return true;
}
// A count type that collects all matching nodes in a bucket.
class BucketCount : public CountType {
struct Count : CountBase {
JS::ubi::Vector<JS::ubi::Node::Id> ids_;
explicit Count(BucketCount& count) : CountBase(count), ids_() {}
};
public:
explicit BucketCount() : CountType() {}
void destructCount(CountBase& countBase) override {
Count& count = static_cast<Count&>(countBase);
count.~Count();
}
CountBasePtr makeCount() override {
return CountBasePtr(js_new<Count>(*this));
}
void traceCount(CountBase& countBase, JSTracer* trc) final {}
bool count(CountBase& countBase, mozilla::MallocSizeOf mallocSizeOf,
const Node& node) override;
bool report(JSContext* cx, CountBase& countBase,
MutableHandleValue report) override;
};
bool BucketCount::count(CountBase& countBase,
mozilla::MallocSizeOf mallocSizeOf, const Node& node) {
Count& count = static_cast<Count&>(countBase);
return count.ids_.append(node.identifier());
}
bool BucketCount::report(JSContext* cx, CountBase& countBase,
MutableHandleValue report) {
Count& count = static_cast<Count&>(countBase);
size_t length = count.ids_.length();
RootedArrayObject arr(cx, NewDenseFullyAllocatedArray(cx, length));
if (!arr) {
return false;
}
arr->ensureDenseInitializedLength(cx, 0, length);
for (size_t i = 0; i < length; i++) {
arr->setDenseElement(i, NumberValue(count.ids_[i]));
}
report.setObject(*arr);
return true;
}
// A type that categorizes nodes by their JavaScript type -- 'objects',
// 'strings', 'scripts', 'domNode', and 'other' -- and then passes the nodes to
// child types.
//
// Implementation details of scripts like jitted code are counted under
// 'scripts'.
class ByCoarseType : public CountType {
CountTypePtr objects;
CountTypePtr scripts;
CountTypePtr strings;
CountTypePtr other;
CountTypePtr domNode;
struct Count : CountBase {
Count(CountType& type, CountBasePtr& objects, CountBasePtr& scripts,
CountBasePtr& strings, CountBasePtr& other, CountBasePtr& domNode)
: CountBase(type),
objects(std::move(objects)),
scripts(std::move(scripts)),
strings(std::move(strings)),
other(std::move(other)),
domNode(std::move(domNode)) {}
CountBasePtr objects;
CountBasePtr scripts;
CountBasePtr strings;
CountBasePtr other;
CountBasePtr domNode;
};
public:
ByCoarseType(CountTypePtr& objects, CountTypePtr& scripts,
CountTypePtr& strings, CountTypePtr& other,
CountTypePtr& domNode)
: CountType(),
objects(std::move(objects)),
scripts(std::move(scripts)),
strings(std::move(strings)),
other(std::move(other)),
domNode(std::move(domNode)) {}
void destructCount(CountBase& countBase) override {
Count& count = static_cast<Count&>(countBase);
count.~Count();
}
CountBasePtr makeCount() override;
void traceCount(CountBase& countBase, JSTracer* trc) override;
bool count(CountBase& countBase, mozilla::MallocSizeOf mallocSizeOf,
const Node& node) override;
bool report(JSContext* cx, CountBase& countBase,
MutableHandleValue report) override;
};
CountBasePtr ByCoarseType::makeCount() {
CountBasePtr objectsCount(objects->makeCount());
CountBasePtr scriptsCount(scripts->makeCount());
CountBasePtr stringsCount(strings->makeCount());
CountBasePtr otherCount(other->makeCount());
CountBasePtr domNodeCount(domNode->makeCount());
if (!objectsCount || !scriptsCount || !stringsCount || !otherCount ||
!domNodeCount) {
return CountBasePtr(nullptr);
}
return CountBasePtr(js_new<Count>(*this, objectsCount, scriptsCount,
stringsCount, otherCount, domNodeCount));
}
void ByCoarseType::traceCount(CountBase& countBase, JSTracer* trc) {
Count& count = static_cast<Count&>(countBase);
count.objects->trace(trc);
count.scripts->trace(trc);
count.strings->trace(trc);
count.other->trace(trc);
count.domNode->trace(trc);
}
bool ByCoarseType::count(CountBase& countBase,
mozilla::MallocSizeOf mallocSizeOf, const Node& node) {
Count& count = static_cast<Count&>(countBase);
switch (node.coarseType()) {
case JS::ubi::CoarseType::Object:
return count.objects->count(mallocSizeOf, node);
case JS::ubi::CoarseType::Script:
return count.scripts->count(mallocSizeOf, node);
case JS::ubi::CoarseType::String:
return count.strings->count(mallocSizeOf, node);
case JS::ubi::CoarseType::Other:
return count.other->count(mallocSizeOf, node);
case JS::ubi::CoarseType::DOMNode:
return count.domNode->count(mallocSizeOf, node);
default:
MOZ_CRASH("bad JS::ubi::CoarseType in JS::ubi::ByCoarseType::count");
return false;
}
}
bool ByCoarseType::report(JSContext* cx, CountBase& countBase,
MutableHandleValue report) {
Count& count = static_cast<Count&>(countBase);
RootedPlainObject obj(cx, NewBuiltinClassInstance<PlainObject>(cx));
if (!obj) {
return false;
}
RootedValue objectsReport(cx);
if (!count.objects->report(cx, &objectsReport) ||
!DefineDataProperty(cx, obj, cx->names().objects, objectsReport))
return false;
RootedValue scriptsReport(cx);
if (!count.scripts->report(cx, &scriptsReport) ||
!DefineDataProperty(cx, obj, cx->names().scripts, scriptsReport))
return false;
RootedValue stringsReport(cx);
if (!count.strings->report(cx, &stringsReport) ||
!DefineDataProperty(cx, obj, cx->names().strings, stringsReport))
return false;
RootedValue otherReport(cx);
if (!count.other->report(cx, &otherReport) ||
!DefineDataProperty(cx, obj, cx->names().other, otherReport))
return false;
RootedValue domReport(cx);
if (!count.domNode->report(cx, &domReport) ||
!DefineDataProperty(cx, obj, cx->names().domNode, domReport))
return false;
report.setObject(*obj);
return true;
}
// Comparison function for sorting hash table entries by the smallest node ID
// they counted. Node IDs are stable and unique, which ensures ordering of
// results never depends on hash table placement or sort algorithm vagaries. The
// arguments are doubly indirect: they're pointers to elements in an array of
// pointers to table entries.
template <typename Entry>
static int compareEntries(const void* lhsVoid, const void* rhsVoid) {
auto lhs = (*static_cast<const Entry* const*>(lhsVoid))
->value()
->smallestNodeIdCounted_;
auto rhs = (*static_cast<const Entry* const*>(rhsVoid))
->value()
->smallestNodeIdCounted_;
// We don't want to just subtract the values, as they're unsigned.
if (lhs < rhs) {
return 1;
}
if (lhs > rhs) {
return -1;
}
return 0;
}
// A hash map mapping from C strings to counts.
using CStringCountMap = HashMap<const char*, CountBasePtr,
mozilla::CStringHasher, SystemAllocPolicy>;
// Convert a HashMap into an object with each key one of the entries from the
// map and each value the associated count's report. For use during census
// reporting.
//
// `Map` must be a `HashMap` from some key type to a `CountBasePtr`.
//
// `GetName` must be a callable type which takes `const Map::Key&` and returns
// `const char*`.
template <class Map, class GetName>
static PlainObject* countMapToObject(JSContext* cx, Map& map, GetName getName) {
// Build a vector of pointers to entries; sort by total; and then use
// that to build the result object. This makes the ordering of entries
// more interesting, and a little less non-deterministic.
JS::ubi::Vector<typename Map::Entry*> entries;
if (!entries.reserve(map.count())) {
ReportOutOfMemory(cx);
return nullptr;
}
for (auto r = map.all(); !r.empty(); r.popFront()) {
entries.infallibleAppend(&r.front());
}
if (entries.length()) {
qsort(entries.begin(), entries.length(), sizeof(*entries.begin()),
compareEntries<typename Map::Entry>);
}
RootedPlainObject obj(cx, NewBuiltinClassInstance<PlainObject>(cx));
if (!obj) {
return nullptr;
}
for (auto& entry : entries) {
CountBasePtr& thenCount = entry->value();
RootedValue thenReport(cx);
if (!thenCount->report(cx, &thenReport)) {
return nullptr;
}
const char* name = getName(entry->key());
MOZ_ASSERT(name);
JSAtom* atom = Atomize(cx, name, strlen(name));
if (!atom) {
return nullptr;
}
RootedId entryId(cx, AtomToId(atom));
if (!DefineDataProperty(cx, obj, entryId, thenReport)) {
return nullptr;
}
}
return obj;
}
template <class Map, class GetName>
static PlainObject* countMap16ToObject(JSContext* cx, Map& map,
GetName getName) {
// Build a vector of pointers to entries; sort by total; and then use
// that to build the result object. This makes the ordering of entries
// more interesting, and a little less non-deterministic.
JS::ubi::Vector<typename Map::Entry*> entries;
if (!entries.reserve(map.count())) {
ReportOutOfMemory(cx);
return nullptr;
}
for (auto r = map.all(); !r.empty(); r.popFront()) {
entries.infallibleAppend(&r.front());
}
if (entries.length()) {
qsort(entries.begin(), entries.length(), sizeof(*entries.begin()),
compareEntries<typename Map::Entry>);
}
RootedPlainObject obj(cx, NewBuiltinClassInstance<PlainObject>(cx));
if (!obj) {
return nullptr;
}
for (auto& entry : entries) {
CountBasePtr& thenCount = entry->value();
RootedValue thenReport(cx);
if (!thenCount->report(cx, &thenReport)) {
return nullptr;
}
const char16_t* name = getName(entry->key());
MOZ_ASSERT(name);
JSAtom* atom = AtomizeChars(cx, name, js_strlen(name));
if (!atom) {
return nullptr;
}
RootedId entryId(cx, AtomToId(atom));
if (!DefineDataProperty(cx, obj, entryId, thenReport)) {
return nullptr;
}
}
return obj;
}
// A type that categorizes nodes that are JSObjects by their class name,
// and places all other nodes in an 'other' category.
class ByObjectClass : public CountType {
// A table mapping class names to their counts. Note that we treat js::Class
// instances with the same name as equal keys. If you have several
// js::Classes with equal names (and we do; as of this writing there were
// six named "Object"), you will get several different js::Classes being
// counted in the same table entry.
using Table = CStringCountMap;
using Entry = Table::Entry;
struct Count : public CountBase {
Table table;
CountBasePtr other;
Count(CountType& type, CountBasePtr& other)
: CountBase(type), other(std::move(other)) {}
};
CountTypePtr classesType;
CountTypePtr otherType;
public:
ByObjectClass(CountTypePtr& classesType, CountTypePtr& otherType)
: CountType(),
classesType(std::move(classesType)),
otherType(std::move(otherType)) {}
void destructCount(CountBase& countBase) override {
Count& count = static_cast<Count&>(countBase);
count.~Count();
}
CountBasePtr makeCount() override;
void traceCount(CountBase& countBase, JSTracer* trc) override;
bool count(CountBase& countBase, mozilla::MallocSizeOf mallocSizeOf,
const Node& node) override;
bool report(JSContext* cx, CountBase& countBase,
MutableHandleValue report) override;
};
CountBasePtr ByObjectClass::makeCount() {
CountBasePtr otherCount(otherType->makeCount());
if (!otherCount) {
return nullptr;
}
auto count = js::MakeUnique<Count>(*this, otherCount);
if (!count) {
return nullptr;
}
return CountBasePtr(count.release());
}
void ByObjectClass::traceCount(CountBase& countBase, JSTracer* trc) {
Count& count = static_cast<Count&>(countBase);
for (Table::Range r = count.table.all(); !r.empty(); r.popFront()) {
r.front().value()->trace(trc);
}
count.other->trace(trc);
}
bool ByObjectClass::count(CountBase& countBase,
mozilla::MallocSizeOf mallocSizeOf,
const Node& node) {
Count& count = static_cast<Count&>(countBase);
const char* className = node.jsObjectClassName();
if (!className) {
return count.other->count(mallocSizeOf, node);
}
Table::AddPtr p = count.table.lookupForAdd(className);
if (!p) {
CountBasePtr classCount(classesType->makeCount());
if (!classCount || !count.table.add(p, className, std::move(classCount))) {
return false;
}
}
return p->value()->count(mallocSizeOf, node);
}
bool ByObjectClass::report(JSContext* cx, CountBase& countBase,
MutableHandleValue report) {
Count& count = static_cast<Count&>(countBase);
RootedPlainObject obj(
cx,
countMapToObject(cx, count.table, [](const char* key) { return key; }));
if (!obj) {
return false;
}
RootedValue otherReport(cx);
if (!count.other->report(cx, &otherReport) ||
!DefineDataProperty(cx, obj, cx->names().other, otherReport))
return false;
report.setObject(*obj);
return true;
}
class ByDomObjectClass : public CountType {
// A table mapping descriptive names to their counts.
using UniqueC16String = JS::UniqueTwoByteChars;
struct UniqueC16StringHasher {
using Lookup = UniqueC16String;
static js::HashNumber hash(const Lookup& lookup) {
return mozilla::HashString(lookup.get());
}
static bool match(const UniqueC16String& key, const Lookup& lookup) {
return CompareChars(key.get(), js_strlen(key.get()), lookup.get(),
js_strlen(lookup.get())) == 0;
}
};
using Table = HashMap<UniqueC16String, CountBasePtr, UniqueC16StringHasher,
SystemAllocPolicy>;
using Entry = Table::Entry;
struct Count : public CountBase {
Table table;
explicit Count(CountType& type) : CountBase(type) {}
};
CountTypePtr classesType;
public:
explicit ByDomObjectClass(CountTypePtr& classesType)
: CountType(), classesType(std::move(classesType)) {}
void destructCount(CountBase& countBase) override {
Count& count = static_cast<Count&>(countBase);
count.~Count();
}
CountBasePtr makeCount() override;
void traceCount(CountBase& countBase, JSTracer* trc) override;
bool count(CountBase& countBase, mozilla::MallocSizeOf mallocSizeOf,
const Node& node) override;
bool report(JSContext* cx, CountBase& countBase,
MutableHandleValue report) override;
};
CountBasePtr ByDomObjectClass::makeCount() {
auto count = js::MakeUnique<Count>(*this);
if (!count) {
return nullptr;
}
return CountBasePtr(count.release());
}
void ByDomObjectClass::traceCount(CountBase& countBase, JSTracer* trc) {
Count& count = static_cast<Count&>(countBase);
for (Table::Range r = count.table.all(); !r.empty(); r.popFront()) {
r.front().value()->trace(trc);
}
}
bool ByDomObjectClass::count(CountBase& countBase,
mozilla::MallocSizeOf mallocSizeOf,
const Node& node) {
Count& count = static_cast<Count&>(countBase);
const char16_t* nodeName = node.descriptiveTypeName();
if (!nodeName) {
return false;
}
UniqueC16String name = DuplicateString(nodeName);
if (!name) {
return false;
}
Table::AddPtr p = count.table.lookupForAdd(name);
if (!p) {
CountBasePtr classesCount(classesType->makeCount());
if (!classesCount ||
!count.table.add(p, std::move(name), std::move(classesCount))) {
return false;
}
}
return p->value()->count(mallocSizeOf, node);
}
bool ByDomObjectClass::report(JSContext* cx, CountBase& countBase,
MutableHandleValue report) {
Count& count = static_cast<Count&>(countBase);
RootedPlainObject obj(
cx, countMap16ToObject(cx, count.table, [](const UniqueC16String& key) {
return key.get();
}));
if (!obj) {
return false;
}
report.setObject(*obj);
return true;
}
// A count type that categorizes nodes by their ubi::Node::typeName.
class ByUbinodeType : public CountType {
// Note that, because ubi::Node::typeName promises to return a specific
// pointer, not just any string whose contents are correct, we can use their
// addresses as hash table keys.
using Table = HashMap<const char16_t*, CountBasePtr,
DefaultHasher<const char16_t*>, SystemAllocPolicy>;
using Entry = Table::Entry;
struct Count : public CountBase {
Table table;
explicit Count(CountType& type) : CountBase(type) {}
};
CountTypePtr entryType;
public:
explicit ByUbinodeType(CountTypePtr& entryType)
: CountType(), entryType(std::move(entryType)) {}
void destructCount(CountBase& countBase) override {
Count& count = static_cast<Count&>(countBase);
count.~Count();
}
CountBasePtr makeCount() override;
void traceCount(CountBase& countBase, JSTracer* trc) override;
bool count(CountBase& countBase, mozilla::MallocSizeOf mallocSizeOf,
const Node& node) override;
bool report(JSContext* cx, CountBase& countBase,
MutableHandleValue report) override;
};
CountBasePtr ByUbinodeType::makeCount() {
auto count = js::MakeUnique<Count>(*this);
if (!count) {
return nullptr;
}
return CountBasePtr(count.release());
}
void ByUbinodeType::traceCount(CountBase& countBase, JSTracer* trc) {
Count& count = static_cast<Count&>(countBase);
for (Table::Range r = count.table.all(); !r.empty(); r.popFront()) {
r.front().value()->trace(trc);
}
}
bool ByUbinodeType::count(CountBase& countBase,
mozilla::MallocSizeOf mallocSizeOf,
const Node& node) {
Count& count = static_cast<Count&>(countBase);
const char16_t* key = node.typeName();
MOZ_ASSERT(key);
Table::AddPtr p = count.table.lookupForAdd(key);
if (!p) {
CountBasePtr typesCount(entryType->makeCount());
if (!typesCount || !count.table.add(p, key, std::move(typesCount))) {
return false;
}
}
return p->value()->count(mallocSizeOf, node);
}
bool ByUbinodeType::report(JSContext* cx, CountBase& countBase,
MutableHandleValue report) {
Count& count = static_cast<Count&>(countBase);
// Build a vector of pointers to entries; sort by total; and then use
// that to build the result object. This makes the ordering of entries
// more interesting, and a little less non-deterministic.
JS::ubi::Vector<Entry*> entries;
if (!entries.reserve(count.table.count())) {
return false;
}
for (Table::Range r = count.table.all(); !r.empty(); r.popFront()) {
entries.infallibleAppend(&r.front());
}
if (entries.length()) {
qsort(entries.begin(), entries.length(), sizeof(*entries.begin()),
compareEntries<Entry>);
}
// Now build the result by iterating over the sorted vector.
RootedPlainObject obj(cx, NewBuiltinClassInstance<PlainObject>(cx));
if (!obj) {
return false;
}
for (Entry** entryPtr = entries.begin(); entryPtr < entries.end();
entryPtr++) {
Entry& entry = **entryPtr;
CountBasePtr& typeCount = entry.value();
RootedValue typeReport(cx);
if (!typeCount->report(cx, &typeReport)) {
return false;
}
const char16_t* name = entry.key();
MOZ_ASSERT(name);
JSAtom* atom = AtomizeChars(cx, name, js_strlen(name));
if (!atom) {
return false;
}
RootedId entryId(cx, AtomToId(atom));
if (!DefineDataProperty(cx, obj, entryId, typeReport)) {
return false;
}
}
report.setObject(*obj);
return true;
}
// A count type that categorizes nodes by the JS stack under which they were
// allocated.
class ByAllocationStack : public CountType {
using Table = HashMap<StackFrame, CountBasePtr, DefaultHasher<StackFrame>,
SystemAllocPolicy>;
using Entry = Table::Entry;
struct Count : public CountBase {
// NOTE: You may look up entries in this table by JS::ubi::StackFrame
// key only during traversal, NOT ONCE TRAVERSAL IS COMPLETE. Once
// traversal is complete, you may only iterate over it.
//
// In this hash table, keys are JSObjects (with some indirection), and
// we use JSObject identity (that is, address identity) as key
// identity. The normal way to support such a table is to make the trace
// function notice keys that have moved and re-key them in the
// table. However, our trace function does *not* rehash; the first GC
// may render the hash table unsearchable.
//
// This is as it should be:
//
// First, the heap traversal phase needs lookups by key to work. But no
// GC may ever occur during a traversal; this is enforced by the
// JS::ubi::BreadthFirst template. So the traceCount function doesn't
// need to do anything to help traversal; it never even runs then.
//
// Second, the report phase needs iteration over the table to work, but
// never looks up entries by key. GC may well occur during this phase:
// we allocate a Map object, and probably cross-compartment wrappers for
// SavedFrame instances as well. If a GC were to occur, it would call
// our traceCount function; if traceCount were to re-key, that would
// ruin the traversal in progress.
//
// So depending on the phase, we either don't need re-keying, or
// can't abide it.
Table table;
CountBasePtr noStack;
Count(CountType& type, CountBasePtr& noStack)
: CountBase(type), noStack(std::move(noStack)) {}
};
CountTypePtr entryType;
CountTypePtr noStackType;
public:
ByAllocationStack(CountTypePtr& entryType, CountTypePtr& noStackType)
: CountType(),
entryType(std::move(entryType)),
noStackType(std::move(noStackType)) {}
void destructCount(CountBase& countBase) override {
Count& count = static_cast<Count&>(countBase);
count.~Count();
}
CountBasePtr makeCount() override;
void traceCount(CountBase& countBase, JSTracer* trc) override;
bool count(CountBase& countBase, mozilla::MallocSizeOf mallocSizeOf,
const Node& node) override;
bool report(JSContext* cx, CountBase& countBase,
MutableHandleValue report) override;
};
CountBasePtr ByAllocationStack::makeCount() {
CountBasePtr noStackCount(noStackType->makeCount());
if (!noStackCount) {
return nullptr;
}
auto count = js::MakeUnique<Count>(*this, noStackCount);
if (!count) {
return nullptr;
}
return CountBasePtr(count.release());
}
void ByAllocationStack::traceCount(CountBase& countBase, JSTracer* trc) {
Count& count = static_cast<Count&>(countBase);
for (Table::Range r = count.table.all(); !r.empty(); r.popFront()) {
// Trace our child Counts.
r.front().value()->trace(trc);
// Trace the StackFrame that is this entry's key. Do not re-key if
// it has moved; see comments for ByAllocationStack::Count::table.
const StackFrame* key = &r.front().key();
auto& k = *const_cast<StackFrame*>(key);
k.trace(trc);
}
count.noStack->trace(trc);
}
bool ByAllocationStack::count(CountBase& countBase,
mozilla::MallocSizeOf mallocSizeOf,
const Node& node) {
Count& count = static_cast<Count&>(countBase);
// If we do have an allocation stack for this node, include it in the
// count for that stack.
if (node.hasAllocationStack()) {
auto allocationStack = node.allocationStack();
auto p = count.table.lookupForAdd(allocationStack);
if (!p) {
CountBasePtr stackCount(entryType->makeCount());
if (!stackCount ||
!count.table.add(p, allocationStack, std::move(stackCount))) {
return false;
}
}
MOZ_ASSERT(p);
return p->value()->count(mallocSizeOf, node);
}
// Otherwise, count it in the "no stack" category.
return count.noStack->count(mallocSizeOf, node);
}
bool ByAllocationStack::report(JSContext* cx, CountBase& countBase,
MutableHandleValue report) {
Count& count = static_cast<Count&>(countBase);
#ifdef DEBUG
// Check that nothing rehashes our table while we hold pointers into it.
mozilla::Generation generation = count.table.generation();
#endif
// Build a vector of pointers to entries; sort by total; and then use
// that to build the result object. This makes the ordering of entries
// more interesting, and a little less non-deterministic.
JS::ubi::Vector<Entry*> entries;
if (!entries.reserve(count.table.count())) {
return false;
}
for (Table::Range r = count.table.all(); !r.empty(); r.popFront()) {
entries.infallibleAppend(&r.front());
}
if (entries.length()) {
qsort(entries.begin(), entries.length(), sizeof(*entries.begin()),
compareEntries<Entry>);
}
// Now build the result by iterating over the sorted vector.
Rooted<MapObject*> map(cx, MapObject::create(cx));
if (!map) {
return false;
}
for (Entry** entryPtr = entries.begin(); entryPtr < entries.end();
entryPtr++) {
Entry& entry = **entryPtr;
MOZ_ASSERT(entry.key());
RootedObject stack(cx);
if (!entry.key().constructSavedFrameStack(cx, &stack) ||
!cx->compartment()->wrap(cx, &stack)) {
return false;
}
RootedValue stackVal(cx, ObjectValue(*stack));
CountBasePtr& stackCount = entry.value();
RootedValue stackReport(cx);
if (!stackCount->report(cx, &stackReport)) {
return false;
}
if (!MapObject::set(cx, map, stackVal, stackReport)) {
return false;
}
}
if (count.noStack->total_ > 0) {
RootedValue noStackReport(cx);
if (!count.noStack->report(cx, &noStackReport)) {
return false;
}
RootedValue noStack(cx, StringValue(cx->names().noStack));
if (!MapObject::set(cx, map, noStack, noStackReport)) {
return false;
}
}
MOZ_ASSERT(generation == count.table.generation());
report.setObject(*map);
return true;
}
// A count type that categorizes nodes by their script's filename.
class ByFilename : public CountType {
using UniqueCString = JS::UniqueChars;
struct UniqueCStringHasher {
using Lookup = UniqueCString;
static js::HashNumber hash(const Lookup& lookup) {
return mozilla::CStringHasher::hash(lookup.get());
}
static bool match(const UniqueCString& key, const Lookup& lookup) {
return mozilla::CStringHasher::match(key.get(), lookup.get());
}
};
// A table mapping filenames to their counts. Note that we treat scripts
// with the same filename as equivalent. If you have several sources with
// the same filename, then all their scripts will get bucketed together.
using Table = HashMap<UniqueCString, CountBasePtr, UniqueCStringHasher,
SystemAllocPolicy>;
using Entry = Table::Entry;
struct Count : public CountBase {
Table table;
CountBasePtr then;
CountBasePtr noFilename;
Count(CountType& type, CountBasePtr&& then, CountBasePtr&& noFilename)
: CountBase(type),
then(std::move(then)),
noFilename(std::move(noFilename)) {}
};
CountTypePtr thenType;
CountTypePtr noFilenameType;
public:
ByFilename(CountTypePtr&& thenType, CountTypePtr&& noFilenameType)
: CountType(),
thenType(std::move(thenType)),
noFilenameType(std::move(noFilenameType)) {}
void destructCount(CountBase& countBase) override {
Count& count = static_cast<Count&>(countBase);
count.~Count();
}