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Issue 2005173003: Immediatelly promote marked objects (Closed) Base URL: https://chromium.googlesource.com/v8/v8.git@master
Patch Set: Rebase master Created 4 years, 6 months ago
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1 // Copyright 2015 the V8 project authors. All rights reserved. 1 // Copyright 2015 the V8 project authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be 2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file. 3 // found in the LICENSE file.
4 4
5 #include "src/heap/scavenger.h" 5 #include "src/heap/scavenger.h"
6 6
7 #include "src/contexts.h" 7 #include "src/contexts.h"
8 #include "src/heap/heap.h" 8 #include "src/heap/heap.h"
9 #include "src/heap/objects-visiting-inl.h" 9 #include "src/heap/objects-visiting-inl.h"
10 #include "src/heap/scavenger-inl.h" 10 #include "src/heap/scavenger-inl.h"
11 #include "src/isolate.h" 11 #include "src/isolate.h"
12 #include "src/log.h" 12 #include "src/log.h"
13 #include "src/profiler/cpu-profiler.h" 13 #include "src/profiler/cpu-profiler.h"
14 14
15 namespace v8 { 15 namespace v8 {
16 namespace internal { 16 namespace internal {
17 17
18 enum LoggingAndProfiling { 18 enum LoggingAndProfiling {
19 LOGGING_AND_PROFILING_ENABLED, 19 LOGGING_AND_PROFILING_ENABLED,
20 LOGGING_AND_PROFILING_DISABLED 20 LOGGING_AND_PROFILING_DISABLED
21 }; 21 };
22 22
23 23
24 enum MarksHandling { TRANSFER_MARKS, IGNORE_MARKS }; 24 enum MarksHandling { TRANSFER_MARKS, IGNORE_MARKS };
25 25
26 26 template <MarksHandling marks_handling, PromotionMode promotion_mode,
27 template <MarksHandling marks_handling,
28 LoggingAndProfiling logging_and_profiling_mode> 27 LoggingAndProfiling logging_and_profiling_mode>
29 class ScavengingVisitor : public StaticVisitorBase { 28 class ScavengingVisitor : public StaticVisitorBase {
30 public: 29 public:
31 static void Initialize() { 30 static void Initialize() {
32 table_.Register(kVisitSeqOneByteString, &EvacuateSeqOneByteString); 31 table_.Register(kVisitSeqOneByteString, &EvacuateSeqOneByteString);
33 table_.Register(kVisitSeqTwoByteString, &EvacuateSeqTwoByteString); 32 table_.Register(kVisitSeqTwoByteString, &EvacuateSeqTwoByteString);
34 table_.Register(kVisitShortcutCandidate, &EvacuateShortcutCandidate); 33 table_.Register(kVisitShortcutCandidate, &EvacuateShortcutCandidate);
35 table_.Register(kVisitByteArray, &EvacuateByteArray); 34 table_.Register(kVisitByteArray, &EvacuateByteArray);
36 table_.Register(kVisitFixedArray, &EvacuateFixedArray); 35 table_.Register(kVisitFixedArray, &EvacuateFixedArray);
37 table_.Register(kVisitFixedDoubleArray, &EvacuateFixedDoubleArray); 36 table_.Register(kVisitFixedDoubleArray, &EvacuateFixedDoubleArray);
(...skipping 157 matching lines...) Expand 10 before | Expand all | Expand 10 after
195 Marking::IsBlack(Marking::MarkBitFrom(object))); 194 Marking::IsBlack(Marking::MarkBitFrom(object)));
196 } 195 }
197 heap->IncrementPromotedObjectsSize(object_size); 196 heap->IncrementPromotedObjectsSize(object_size);
198 return true; 197 return true;
199 } 198 }
200 return false; 199 return false;
201 } 200 }
202 201
203 template <ObjectContents object_contents, AllocationAlignment alignment> 202 template <ObjectContents object_contents, AllocationAlignment alignment>
204 static inline void EvacuateObject(Map* map, HeapObject** slot, 203 static inline void EvacuateObject(Map* map, HeapObject** slot,
205 HeapObject* object, int object_size, 204 HeapObject* object, int object_size) {
206 PromotionMode promotion_mode) {
207 SLOW_DCHECK(object_size <= Page::kAllocatableMemory); 205 SLOW_DCHECK(object_size <= Page::kAllocatableMemory);
208 SLOW_DCHECK(object->Size() == object_size); 206 SLOW_DCHECK(object->Size() == object_size);
209 Heap* heap = map->GetHeap(); 207 Heap* heap = map->GetHeap();
210 208
211 if (promotion_mode != FORCE_PROMOTION && 209 if (!heap->ShouldBePromoted<promotion_mode>(object->address(),
212 !heap->ShouldBePromoted(object->address(), object_size)) { 210 object_size)) {
213 // A semi-space copy may fail due to fragmentation. In that case, we 211 // A semi-space copy may fail due to fragmentation. In that case, we
214 // try to promote the object. 212 // try to promote the object.
215 if (SemiSpaceCopyObject<alignment>(map, slot, object, object_size)) { 213 if (SemiSpaceCopyObject<alignment>(map, slot, object, object_size)) {
216 return; 214 return;
217 } 215 }
218 } 216 }
219 217
220 if (PromoteObject<object_contents, alignment>(map, slot, object, 218 if (PromoteObject<object_contents, alignment>(map, slot, object,
221 object_size)) { 219 object_size)) {
222 return; 220 return;
223 } 221 }
224 if (promotion_mode == FORCE_PROMOTION) { 222 if (promotion_mode == FORCE_PROMOTION) {
225 FatalProcessOutOfMemory("Scavenger: forced promotion\n"); 223 FatalProcessOutOfMemory("Scavenger: forced promotion\n");
226 } 224 }
225 if (promotion_mode == PROMOTE_MARKED) {
226 FatalProcessOutOfMemory("Scavenger: promoting marked\n");
227 }
227 // If promotion failed, we try to copy the object to the other semi-space 228 // If promotion failed, we try to copy the object to the other semi-space
228 if (SemiSpaceCopyObject<alignment>(map, slot, object, object_size)) return; 229 if (SemiSpaceCopyObject<alignment>(map, slot, object, object_size)) return;
229 230
230 FatalProcessOutOfMemory("Scavenger: semi-space copy\n"); 231 FatalProcessOutOfMemory("Scavenger: semi-space copy\n");
231 } 232 }
232 233
233 static inline void EvacuateJSFunction(Map* map, HeapObject** slot, 234 static inline void EvacuateJSFunction(Map* map, HeapObject** slot,
234 HeapObject* object, 235 HeapObject* object) {
235 PromotionMode promotion_mode) { 236 ObjectEvacuationStrategy<POINTER_OBJECT>::Visit(map, slot, object);
236 ObjectEvacuationStrategy<POINTER_OBJECT>::Visit(map, slot, object,
237 promotion_mode);
238 237
239 if (marks_handling == IGNORE_MARKS) return; 238 if (marks_handling == IGNORE_MARKS) return;
240 239
241 MapWord map_word = object->map_word(); 240 MapWord map_word = object->map_word();
242 DCHECK(map_word.IsForwardingAddress()); 241 DCHECK(map_word.IsForwardingAddress());
243 HeapObject* target = map_word.ToForwardingAddress(); 242 HeapObject* target = map_word.ToForwardingAddress();
244 243
245 MarkBit mark_bit = Marking::MarkBitFrom(target); 244 MarkBit mark_bit = Marking::MarkBitFrom(target);
246 if (Marking::IsBlack(mark_bit)) { 245 if (Marking::IsBlack(mark_bit)) {
247 // This object is black and it might not be rescanned by marker. 246 // This object is black and it might not be rescanned by marker.
248 // We should explicitly record code entry slot for compaction because 247 // We should explicitly record code entry slot for compaction because
249 // promotion queue processing (IteratePromotedObjectPointers) will 248 // promotion queue processing (IteratePromotedObjectPointers) will
250 // miss it as it is not HeapObject-tagged. 249 // miss it as it is not HeapObject-tagged.
251 Address code_entry_slot = 250 Address code_entry_slot =
252 target->address() + JSFunction::kCodeEntryOffset; 251 target->address() + JSFunction::kCodeEntryOffset;
253 Code* code = Code::cast(Code::GetObjectFromEntryAddress(code_entry_slot)); 252 Code* code = Code::cast(Code::GetObjectFromEntryAddress(code_entry_slot));
254 map->GetHeap()->mark_compact_collector()->RecordCodeEntrySlot( 253 map->GetHeap()->mark_compact_collector()->RecordCodeEntrySlot(
255 target, code_entry_slot, code); 254 target, code_entry_slot, code);
256 } 255 }
257 } 256 }
258 257
259 static inline void EvacuateFixedArray(Map* map, HeapObject** slot, 258 static inline void EvacuateFixedArray(Map* map, HeapObject** slot,
260 HeapObject* object, 259 HeapObject* object) {
261 PromotionMode promotion_mode) {
262 int length = reinterpret_cast<FixedArray*>(object)->synchronized_length(); 260 int length = reinterpret_cast<FixedArray*>(object)->synchronized_length();
263 int object_size = FixedArray::SizeFor(length); 261 int object_size = FixedArray::SizeFor(length);
264 EvacuateObject<POINTER_OBJECT, kWordAligned>(map, slot, object, object_size, 262 EvacuateObject<POINTER_OBJECT, kWordAligned>(map, slot, object,
265 promotion_mode); 263 object_size);
266 } 264 }
267 265
268 static inline void EvacuateFixedDoubleArray(Map* map, HeapObject** slot, 266 static inline void EvacuateFixedDoubleArray(Map* map, HeapObject** slot,
269 HeapObject* object, 267 HeapObject* object) {
270 PromotionMode promotion_mode) {
271 int length = reinterpret_cast<FixedDoubleArray*>(object)->length(); 268 int length = reinterpret_cast<FixedDoubleArray*>(object)->length();
272 int object_size = FixedDoubleArray::SizeFor(length); 269 int object_size = FixedDoubleArray::SizeFor(length);
273 EvacuateObject<DATA_OBJECT, kDoubleAligned>(map, slot, object, object_size, 270 EvacuateObject<DATA_OBJECT, kDoubleAligned>(map, slot, object, object_size);
274 promotion_mode);
275 } 271 }
276 272
277 static inline void EvacuateFixedTypedArray(Map* map, HeapObject** slot, 273 static inline void EvacuateFixedTypedArray(Map* map, HeapObject** slot,
278 HeapObject* object, 274 HeapObject* object) {
279 PromotionMode promotion_mode) {
280 int object_size = reinterpret_cast<FixedTypedArrayBase*>(object)->size(); 275 int object_size = reinterpret_cast<FixedTypedArrayBase*>(object)->size();
281 EvacuateObject<POINTER_OBJECT, kWordAligned>(map, slot, object, object_size, 276 EvacuateObject<POINTER_OBJECT, kWordAligned>(map, slot, object,
282 promotion_mode); 277 object_size);
283 } 278 }
284 279
285 static inline void EvacuateFixedFloat64Array(Map* map, HeapObject** slot, 280 static inline void EvacuateFixedFloat64Array(Map* map, HeapObject** slot,
286 HeapObject* object, 281 HeapObject* object) {
287 PromotionMode promotion_mode) {
288 int object_size = reinterpret_cast<FixedFloat64Array*>(object)->size(); 282 int object_size = reinterpret_cast<FixedFloat64Array*>(object)->size();
289 EvacuateObject<POINTER_OBJECT, kDoubleAligned>(map, slot, object, 283 EvacuateObject<POINTER_OBJECT, kDoubleAligned>(map, slot, object,
290 object_size, promotion_mode); 284 object_size);
291 } 285 }
292 286
293 static inline void EvacuateJSArrayBuffer(Map* map, HeapObject** slot, 287 static inline void EvacuateJSArrayBuffer(Map* map, HeapObject** slot,
294 HeapObject* object, 288 HeapObject* object) {
295 PromotionMode promotion_mode) { 289 ObjectEvacuationStrategy<POINTER_OBJECT>::Visit(map, slot, object);
296 ObjectEvacuationStrategy<POINTER_OBJECT>::Visit(map, slot, object,
297 promotion_mode);
298 290
299 Heap* heap = map->GetHeap(); 291 Heap* heap = map->GetHeap();
300 MapWord map_word = object->map_word(); 292 MapWord map_word = object->map_word();
301 DCHECK(map_word.IsForwardingAddress()); 293 DCHECK(map_word.IsForwardingAddress());
302 HeapObject* target = map_word.ToForwardingAddress(); 294 HeapObject* target = map_word.ToForwardingAddress();
303 if (!heap->InNewSpace(target)) { 295 if (!heap->InNewSpace(target)) {
304 heap->array_buffer_tracker()->Promote(JSArrayBuffer::cast(target)); 296 heap->array_buffer_tracker()->Promote(JSArrayBuffer::cast(target));
305 } 297 }
306 } 298 }
307 299
308 static inline void EvacuateByteArray(Map* map, HeapObject** slot, 300 static inline void EvacuateByteArray(Map* map, HeapObject** slot,
309 HeapObject* object, 301 HeapObject* object) {
310 PromotionMode promotion_mode) {
311 int object_size = reinterpret_cast<ByteArray*>(object)->ByteArraySize(); 302 int object_size = reinterpret_cast<ByteArray*>(object)->ByteArraySize();
312 EvacuateObject<DATA_OBJECT, kWordAligned>(map, slot, object, object_size, 303 EvacuateObject<DATA_OBJECT, kWordAligned>(map, slot, object, object_size);
313 promotion_mode);
314 } 304 }
315 305
316 static inline void EvacuateSeqOneByteString(Map* map, HeapObject** slot, 306 static inline void EvacuateSeqOneByteString(Map* map, HeapObject** slot,
317 HeapObject* object, 307 HeapObject* object) {
318 PromotionMode promotion_mode) {
319 int object_size = SeqOneByteString::cast(object) 308 int object_size = SeqOneByteString::cast(object)
320 ->SeqOneByteStringSize(map->instance_type()); 309 ->SeqOneByteStringSize(map->instance_type());
321 EvacuateObject<DATA_OBJECT, kWordAligned>(map, slot, object, object_size, 310 EvacuateObject<DATA_OBJECT, kWordAligned>(map, slot, object, object_size);
322 promotion_mode);
323 } 311 }
324 312
325 static inline void EvacuateSeqTwoByteString(Map* map, HeapObject** slot, 313 static inline void EvacuateSeqTwoByteString(Map* map, HeapObject** slot,
326 HeapObject* object, 314 HeapObject* object) {
327 PromotionMode promotion_mode) {
328 int object_size = SeqTwoByteString::cast(object) 315 int object_size = SeqTwoByteString::cast(object)
329 ->SeqTwoByteStringSize(map->instance_type()); 316 ->SeqTwoByteStringSize(map->instance_type());
330 EvacuateObject<DATA_OBJECT, kWordAligned>(map, slot, object, object_size, 317 EvacuateObject<DATA_OBJECT, kWordAligned>(map, slot, object, object_size);
331 promotion_mode);
332 } 318 }
333 319
334 static inline void EvacuateShortcutCandidate(Map* map, HeapObject** slot, 320 static inline void EvacuateShortcutCandidate(Map* map, HeapObject** slot,
335 HeapObject* object, 321 HeapObject* object) {
336 PromotionMode promotion_mode) {
337 DCHECK(IsShortcutCandidate(map->instance_type())); 322 DCHECK(IsShortcutCandidate(map->instance_type()));
338 323
339 Heap* heap = map->GetHeap(); 324 Heap* heap = map->GetHeap();
340 325
341 if (marks_handling == IGNORE_MARKS && 326 if (marks_handling == IGNORE_MARKS &&
342 ConsString::cast(object)->unchecked_second() == heap->empty_string()) { 327 ConsString::cast(object)->unchecked_second() == heap->empty_string()) {
343 HeapObject* first = 328 HeapObject* first =
344 HeapObject::cast(ConsString::cast(object)->unchecked_first()); 329 HeapObject::cast(ConsString::cast(object)->unchecked_first());
345 330
346 *slot = first; 331 *slot = first;
347 332
348 if (!heap->InNewSpace(first)) { 333 if (!heap->InNewSpace(first)) {
349 object->set_map_word(MapWord::FromForwardingAddress(first)); 334 object->set_map_word(MapWord::FromForwardingAddress(first));
350 return; 335 return;
351 } 336 }
352 337
353 MapWord first_word = first->map_word(); 338 MapWord first_word = first->map_word();
354 if (first_word.IsForwardingAddress()) { 339 if (first_word.IsForwardingAddress()) {
355 HeapObject* target = first_word.ToForwardingAddress(); 340 HeapObject* target = first_word.ToForwardingAddress();
356 341
357 *slot = target; 342 *slot = target;
358 object->set_map_word(MapWord::FromForwardingAddress(target)); 343 object->set_map_word(MapWord::FromForwardingAddress(target));
359 return; 344 return;
360 } 345 }
361 346
362 Scavenger::ScavengeObjectSlow(slot, first, promotion_mode); 347 Scavenger::ScavengeObjectSlow<promotion_mode>(slot, first);
363 object->set_map_word(MapWord::FromForwardingAddress(*slot)); 348 object->set_map_word(MapWord::FromForwardingAddress(*slot));
364 return; 349 return;
365 } 350 }
366 351
367 int object_size = ConsString::kSize; 352 int object_size = ConsString::kSize;
368 EvacuateObject<POINTER_OBJECT, kWordAligned>(map, slot, object, object_size, 353 EvacuateObject<POINTER_OBJECT, kWordAligned>(map, slot, object,
369 promotion_mode); 354 object_size);
370 } 355 }
371 356
372 template <ObjectContents object_contents> 357 template <ObjectContents object_contents>
373 class ObjectEvacuationStrategy { 358 class ObjectEvacuationStrategy {
374 public: 359 public:
375 template <int object_size> 360 template <int object_size>
376 static inline void VisitSpecialized(Map* map, HeapObject** slot, 361 static inline void VisitSpecialized(Map* map, HeapObject** slot,
377 HeapObject* object, 362 HeapObject* object) {
378 PromotionMode promotion_mode) { 363 EvacuateObject<object_contents, kWordAligned>(map, slot, object,
379 EvacuateObject<object_contents, kWordAligned>( 364 object_size);
380 map, slot, object, object_size, promotion_mode);
381 } 365 }
382 366
383 static inline void Visit(Map* map, HeapObject** slot, HeapObject* object, 367 static inline void Visit(Map* map, HeapObject** slot, HeapObject* object) {
384 PromotionMode promotion_mode) {
385 int object_size = map->instance_size(); 368 int object_size = map->instance_size();
386 EvacuateObject<object_contents, kWordAligned>( 369 EvacuateObject<object_contents, kWordAligned>(map, slot, object,
387 map, slot, object, object_size, promotion_mode); 370 object_size);
388 } 371 }
389 }; 372 };
390 373
391 static VisitorDispatchTable<ScavengingCallback> table_; 374 static VisitorDispatchTable<ScavengingCallback> table_;
392 }; 375 };
393 376
394 377 template <MarksHandling marks_handling, PromotionMode promotion_mode,
395 template <MarksHandling marks_handling,
396 LoggingAndProfiling logging_and_profiling_mode> 378 LoggingAndProfiling logging_and_profiling_mode>
397 VisitorDispatchTable<ScavengingCallback> 379 VisitorDispatchTable<ScavengingCallback> ScavengingVisitor<
398 ScavengingVisitor<marks_handling, logging_and_profiling_mode>::table_; 380 marks_handling, promotion_mode, logging_and_profiling_mode>::table_;
399
400 381
401 // static 382 // static
402 void Scavenger::Initialize() { 383 void Scavenger::Initialize() {
403 ScavengingVisitor<TRANSFER_MARKS, 384 ScavengingVisitor<TRANSFER_MARKS, PROMOTE_MARKED,
404 LOGGING_AND_PROFILING_DISABLED>::Initialize(); 385 LOGGING_AND_PROFILING_DISABLED>::Initialize();
405 ScavengingVisitor<IGNORE_MARKS, LOGGING_AND_PROFILING_DISABLED>::Initialize(); 386 ScavengingVisitor<IGNORE_MARKS, DEFAULT_PROMOTION,
406 ScavengingVisitor<TRANSFER_MARKS, 387 LOGGING_AND_PROFILING_DISABLED>::Initialize();
388 ScavengingVisitor<TRANSFER_MARKS, PROMOTE_MARKED,
407 LOGGING_AND_PROFILING_ENABLED>::Initialize(); 389 LOGGING_AND_PROFILING_ENABLED>::Initialize();
408 ScavengingVisitor<IGNORE_MARKS, LOGGING_AND_PROFILING_ENABLED>::Initialize(); 390 ScavengingVisitor<IGNORE_MARKS, DEFAULT_PROMOTION,
391 LOGGING_AND_PROFILING_ENABLED>::Initialize();
409 } 392 }
410 393
411 394
412 // static
413 void Scavenger::ScavengeObjectSlow(HeapObject** p, HeapObject* object,
414 PromotionMode promotion_mode) {
415 SLOW_DCHECK(object->GetIsolate()->heap()->InFromSpace(object));
416 MapWord first_word = object->map_word();
417 SLOW_DCHECK(!first_word.IsForwardingAddress());
418 Map* map = first_word.ToMap();
419 Scavenger* scavenger = map->GetHeap()->scavenge_collector_;
420 scavenger->scavenging_visitors_table_.GetVisitor(map)(map, p, object,
421 promotion_mode);
422 }
423
424
425 void Scavenger::SelectScavengingVisitorsTable() { 395 void Scavenger::SelectScavengingVisitorsTable() {
426 bool logging_and_profiling = 396 bool logging_and_profiling =
427 FLAG_verify_predictable || isolate()->logger()->is_logging() || 397 FLAG_verify_predictable || isolate()->logger()->is_logging() ||
428 isolate()->cpu_profiler()->is_profiling() || 398 isolate()->cpu_profiler()->is_profiling() ||
429 (isolate()->heap_profiler() != NULL && 399 (isolate()->heap_profiler() != NULL &&
430 isolate()->heap_profiler()->is_tracking_object_moves()); 400 isolate()->heap_profiler()->is_tracking_object_moves());
431 401
432 if (!heap()->incremental_marking()->IsMarking()) { 402 if (!heap()->incremental_marking()->IsMarking()) {
433 if (!logging_and_profiling) { 403 if (!logging_and_profiling) {
434 scavenging_visitors_table_.CopyFrom( 404 scavenging_visitors_table_.CopyFrom(
435 ScavengingVisitor<IGNORE_MARKS, 405 ScavengingVisitor<IGNORE_MARKS, DEFAULT_PROMOTION,
436 LOGGING_AND_PROFILING_DISABLED>::GetTable()); 406 LOGGING_AND_PROFILING_DISABLED>::GetTable());
437 } else { 407 } else {
438 scavenging_visitors_table_.CopyFrom( 408 scavenging_visitors_table_.CopyFrom(
439 ScavengingVisitor<IGNORE_MARKS, 409 ScavengingVisitor<IGNORE_MARKS, DEFAULT_PROMOTION,
440 LOGGING_AND_PROFILING_ENABLED>::GetTable()); 410 LOGGING_AND_PROFILING_ENABLED>::GetTable());
441 } 411 }
442 } else { 412 } else {
443 if (!logging_and_profiling) { 413 if (!logging_and_profiling) {
444 scavenging_visitors_table_.CopyFrom( 414 scavenging_visitors_table_.CopyFrom(
445 ScavengingVisitor<TRANSFER_MARKS, 415 ScavengingVisitor<TRANSFER_MARKS, PROMOTE_MARKED,
446 LOGGING_AND_PROFILING_DISABLED>::GetTable()); 416 LOGGING_AND_PROFILING_DISABLED>::GetTable());
447 } else { 417 } else {
448 scavenging_visitors_table_.CopyFrom( 418 scavenging_visitors_table_.CopyFrom(
449 ScavengingVisitor<TRANSFER_MARKS, 419 ScavengingVisitor<TRANSFER_MARKS, PROMOTE_MARKED,
450 LOGGING_AND_PROFILING_ENABLED>::GetTable()); 420 LOGGING_AND_PROFILING_ENABLED>::GetTable());
451 } 421 }
452 422
453 if (heap()->incremental_marking()->IsCompacting()) { 423 if (heap()->incremental_marking()->IsCompacting()) {
454 // When compacting forbid short-circuiting of cons-strings. 424 // When compacting forbid short-circuiting of cons-strings.
455 // Scavenging code relies on the fact that new space object 425 // Scavenging code relies on the fact that new space object
456 // can't be evacuated into evacuation candidate but 426 // can't be evacuated into evacuation candidate but
457 // short-circuiting violates this assumption. 427 // short-circuiting violates this assumption.
458 scavenging_visitors_table_.Register( 428 scavenging_visitors_table_.Register(
459 StaticVisitorBase::kVisitShortcutCandidate, 429 StaticVisitorBase::kVisitShortcutCandidate,
460 scavenging_visitors_table_.GetVisitorById( 430 scavenging_visitors_table_.GetVisitorById(
461 StaticVisitorBase::kVisitConsString)); 431 StaticVisitorBase::kVisitConsString));
462 } 432 }
463 } 433 }
464 } 434 }
465 435
466 436
467 Isolate* Scavenger::isolate() { return heap()->isolate(); } 437 Isolate* Scavenger::isolate() { return heap()->isolate(); }
468 438
469 439
470 void ScavengeVisitor::VisitPointer(Object** p) { ScavengePointer(p); }
471
472
473 void ScavengeVisitor::VisitPointers(Object** start, Object** end) {
474 // Copy all HeapObject pointers in [start, end)
475 for (Object** p = start; p < end; p++) ScavengePointer(p);
476 }
477
478
479 void ScavengeVisitor::ScavengePointer(Object** p) {
480 Object* object = *p;
481 if (!heap_->InNewSpace(object)) return;
482 Scavenger::ScavengeObject(reinterpret_cast<HeapObject**>(p),
483 reinterpret_cast<HeapObject*>(object));
484 }
485
486 } // namespace internal 440 } // namespace internal
487 } // namespace v8 441 } // namespace v8
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