| // Copyright 2012 the V8 project authors. All rights reserved. |
| // Redistribution and use in source and binary forms, with or without |
| // modification, are permitted provided that the following conditions are |
| // met: |
| // |
| // * Redistributions of source code must retain the above copyright |
| // notice, this list of conditions and the following disclaimer. |
| // * 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. |
| // * Neither the name of Google Inc. nor the names of its |
| // contributors may be used to endorse or promote products derived |
| // from this software without specific prior written permission. |
| // |
| // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
| // "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 THE COPYRIGHT |
| // OWNER 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. |
| |
| #include "v8.h" |
| |
| #include "objects.h" |
| #include "transitions-inl.h" |
| #include "utils.h" |
| |
| namespace v8 { |
| namespace internal { |
| |
| |
| static MaybeObject* AllocateRaw(Isolate* isolate, int length) { |
| // Use FixedArray to not use TransitionArray::cast on incomplete object. |
| FixedArray* array; |
| MaybeObject* maybe_array = isolate->heap()->AllocateFixedArray(length); |
| if (!maybe_array->To(&array)) return maybe_array; |
| return array; |
| } |
| |
| |
| MaybeObject* TransitionArray::Allocate(Isolate* isolate, |
| int number_of_transitions) { |
| FixedArray* array; |
| MaybeObject* maybe_array = |
| AllocateRaw(isolate, ToKeyIndex(number_of_transitions)); |
| if (!maybe_array->To(&array)) return maybe_array; |
| array->set(kPrototypeTransitionsIndex, Smi::FromInt(0)); |
| return array; |
| } |
| |
| |
| MaybeObject* TransitionArray::AllocateSimple(Isolate* isolate, |
| Map* target) { |
| FixedArray* array; |
| MaybeObject* maybe_array = |
| AllocateRaw(isolate, kSimpleTransitionSize); |
| if (!maybe_array->To(&array)) return maybe_array; |
| array->set(kSimpleTransitionTarget, target); |
| return array; |
| } |
| |
| |
| void TransitionArray::NoIncrementalWriteBarrierCopyFrom(TransitionArray* origin, |
| int origin_transition, |
| int target_transition) { |
| NoIncrementalWriteBarrierSet(target_transition, |
| origin->GetKey(origin_transition), |
| origin->GetTarget(origin_transition)); |
| } |
| |
| |
| static bool InsertionPointFound(Name* key1, Name* key2) { |
| return key1->Hash() > key2->Hash(); |
| } |
| |
| |
| Handle<TransitionArray> TransitionArray::NewWith(Handle<Map> map, |
| Handle<Name> name, |
| Handle<Map> target, |
| SimpleTransitionFlag flag) { |
| Handle<TransitionArray> result; |
| Factory* factory = name->GetIsolate()->factory(); |
| |
| if (flag == SIMPLE_TRANSITION) { |
| result = factory->NewSimpleTransitionArray(target); |
| } else { |
| result = factory->NewTransitionArray(1); |
| result->NoIncrementalWriteBarrierSet(0, *name, *target); |
| } |
| result->set_back_pointer_storage(map->GetBackPointer()); |
| return result; |
| } |
| |
| |
| MaybeObject* TransitionArray::ExtendToFullTransitionArray() { |
| ASSERT(!IsFullTransitionArray()); |
| int nof = number_of_transitions(); |
| TransitionArray* result; |
| MaybeObject* maybe_result = Allocate(GetIsolate(), nof); |
| if (!maybe_result->To(&result)) return maybe_result; |
| |
| if (nof == 1) { |
| result->NoIncrementalWriteBarrierCopyFrom(this, kSimpleTransitionIndex, 0); |
| } |
| |
| result->set_back_pointer_storage(back_pointer_storage()); |
| return result; |
| } |
| |
| |
| Handle<TransitionArray> TransitionArray::CopyInsert(Handle<Map> map, |
| Handle<Name> name, |
| Handle<Map> target, |
| SimpleTransitionFlag flag) { |
| if (!map->HasTransitionArray()) { |
| return TransitionArray::NewWith(map, name, target, flag); |
| } |
| |
| int number_of_transitions = map->transitions()->number_of_transitions(); |
| int new_size = number_of_transitions; |
| |
| int insertion_index = map->transitions()->Search(*name); |
| if (insertion_index == kNotFound) ++new_size; |
| |
| Handle<TransitionArray> result = |
| map->GetIsolate()->factory()->NewTransitionArray(new_size); |
| |
| // The map's transition array may have disappeared or grown smaller during |
| // the allocation above as it was weakly traversed. Trim the result copy if |
| // needed, and recompute variables. |
| DisallowHeapAllocation no_gc; |
| if (!map->HasTransitionArray()) { |
| if (flag == SIMPLE_TRANSITION) { |
| ASSERT(result->length() >= kSimpleTransitionSize); |
| result->Shrink(kSimpleTransitionSize); |
| result->set(kSimpleTransitionTarget, *target); |
| } else { |
| ASSERT(result->length() >= ToKeyIndex(1)); |
| result->Shrink(ToKeyIndex(1)); |
| result->set(kPrototypeTransitionsIndex, Smi::FromInt(0)); |
| result->NoIncrementalWriteBarrierSet(0, *name, *target); |
| } |
| result->set_back_pointer_storage(map->GetBackPointer()); |
| |
| return result; |
| } |
| |
| TransitionArray* array = map->transitions(); |
| if (array->number_of_transitions() != number_of_transitions) { |
| ASSERT(array->number_of_transitions() < number_of_transitions); |
| |
| number_of_transitions = array->number_of_transitions(); |
| new_size = number_of_transitions; |
| |
| insertion_index = array->Search(*name); |
| if (insertion_index == kNotFound) ++new_size; |
| |
| result->Shrink(ToKeyIndex(new_size)); |
| } |
| |
| if (array->HasPrototypeTransitions()) { |
| result->SetPrototypeTransitions(array->GetPrototypeTransitions()); |
| } |
| |
| if (insertion_index != kNotFound) { |
| for (int i = 0; i < number_of_transitions; ++i) { |
| if (i != insertion_index) { |
| result->NoIncrementalWriteBarrierCopyFrom(array, i, i); |
| } |
| } |
| result->NoIncrementalWriteBarrierSet(insertion_index, *name, *target); |
| result->set_back_pointer_storage(array->back_pointer_storage()); |
| return result; |
| } |
| |
| insertion_index = 0; |
| for (; insertion_index < number_of_transitions; ++insertion_index) { |
| if (InsertionPointFound(array->GetKey(insertion_index), *name)) break; |
| result->NoIncrementalWriteBarrierCopyFrom( |
| array, insertion_index, insertion_index); |
| } |
| |
| result->NoIncrementalWriteBarrierSet(insertion_index, *name, *target); |
| |
| for (; insertion_index < number_of_transitions; ++insertion_index) { |
| result->NoIncrementalWriteBarrierCopyFrom( |
| array, insertion_index, insertion_index + 1); |
| } |
| |
| result->set_back_pointer_storage(array->back_pointer_storage()); |
| return result; |
| } |
| |
| |
| } } // namespace v8::internal |