src/transitions-inl.h

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  27
  28 #ifndef V8_TRANSITIONS_INL_H_
  29 #define V8_TRANSITIONS_INL_H_
  30
  31 #include "objects-inl.h"
  32 #include "transitions.h"
  33
  34 namespace v8 {
  35 namespace internal {
  36
  37
  38 #define FIELD_ADDR(p, offset) \
  39   (reinterpret_cast<byte*>(p) + offset - kHeapObjectTag)
  40
  41 #define WRITE_FIELD(p, offset, value) \
  42   (*reinterpret_cast<Object**>(FIELD_ADDR(p, offset)) = value)
  43
  44 #define CONDITIONAL_WRITE_BARRIER(heap, object, offset, value, mode)    \
  45   if (mode == UPDATE_WRITE_BARRIER) {                                   \
  46     heap->incremental_marking()->RecordWrite(                           \
  47       object, HeapObject::RawField(object, offset), value);             \
  48     if (heap->InNewSpace(value)) {                                      \
  49       heap->RecordWrite(object->address(), offset);                     \
  50     }                                                                   \
  51   }
  52
  53
  54 TransitionArray* TransitionArray::cast(Object* object) {
  55   ASSERT(object->IsTransitionArray());
  56   return reinterpret_cast<TransitionArray*>(object);
  57 }
  58
  59
  60 Map* TransitionArray::elements_transition() {
  61   Object* transition_map = get(kElementsTransitionIndex);
  62   return Map::cast(transition_map);
  63 }
  64
  65
  66 void TransitionArray::ClearElementsTransition() {
  67   WRITE_FIELD(this, kElementsTransitionOffset, Smi::FromInt(0));
  68 }
  69
  70
  71 bool TransitionArray::HasElementsTransition() {
  72   return get(kElementsTransitionIndex) != Smi::FromInt(0);
  73 }
  74
  75
  76 void TransitionArray::set_elements_transition(Map* transition_map,
  77                                               WriteBarrierMode mode) {
  78   Heap* heap = GetHeap();
  79   WRITE_FIELD(this, kElementsTransitionOffset, transition_map);
  80   CONDITIONAL_WRITE_BARRIER(
  81       heap, this, kElementsTransitionOffset, transition_map, mode);
  82 }
  83
  84
  85 bool TransitionArray::HasPrototypeTransitions() {
  86   Object* prototype_transitions = get(kPrototypeTransitionsIndex);
  87   return prototype_transitions != Smi::FromInt(0);
  88 }
  89
  90
  91 FixedArray* TransitionArray::GetPrototypeTransitions() {
  92   Object* prototype_transitions = get(kPrototypeTransitionsIndex);
  93   return FixedArray::cast(prototype_transitions);
  94 }
  95
  96
  97 HeapObject* TransitionArray::UncheckedPrototypeTransitions() {
  98   Object* prototype_transitions = get(kPrototypeTransitionsIndex);
  99   if (prototype_transitions == Smi::FromInt(0)) return NULL;
 100   return reinterpret_cast<HeapObject*>(prototype_transitions);
 101 }
 102
 103
 104 void TransitionArray::SetPrototypeTransitions(FixedArray* transitions,
 105                                               WriteBarrierMode mode) {
 106   ASSERT(this != NULL);
 107   ASSERT(transitions->IsFixedArray());
 108   Heap* heap = GetHeap();
 109   WRITE_FIELD(this, kPrototypeTransitionsOffset, transitions);
 110   CONDITIONAL_WRITE_BARRIER(
 111       heap, this, kPrototypeTransitionsOffset, transitions, mode);
 112 }
 113
 114
 115 Object** TransitionArray::GetPrototypeTransitionsSlot() {
 116   return HeapObject::RawField(reinterpret_cast<HeapObject*>(this),
 117                               kPrototypeTransitionsOffset);
 118 }
 119
 120
 121 Object** TransitionArray::GetKeySlot(int transition_number) {
 122   ASSERT(transition_number < number_of_transitions());
 123   return HeapObject::RawField(
 124       reinterpret_cast<HeapObject*>(this),
 125       OffsetOfElementAt(ToKeyIndex(transition_number)));
 126 }
 127
 128
 129 String* TransitionArray::GetKey(int transition_number) {
 130   ASSERT(transition_number < number_of_transitions());
 131   return String::cast(get(ToKeyIndex(transition_number)));
 132 }
 133
 134
 135 void TransitionArray::SetKey(int transition_number, String* key) {
 136   ASSERT(transition_number < number_of_transitions());
 137   set(ToKeyIndex(transition_number), key);
 138 }
 139
 140
 141 Object* TransitionArray::GetValue(int transition_number) {
 142   ASSERT(transition_number < number_of_transitions());
 143   return get(ToValueIndex(transition_number));
 144 }
 145
 146
 147 Object** TransitionArray::GetValueSlot(int transition_number) {
 148   ASSERT(transition_number < number_of_transitions());
 149   return HeapObject::RawField(
 150       reinterpret_cast<HeapObject*>(this),
 151       OffsetOfElementAt(ToValueIndex(transition_number)));
 152 }
 153
 154
 155 void TransitionArray::SetValue(int transition_number, Object* value) {
 156   ASSERT(transition_number < number_of_transitions());
 157   set(ToValueIndex(transition_number), value);
 158 }
 159
 160
 161 Map* TransitionArray::GetTargetMap(int transition_number) {
 162   Object* value = GetValue(transition_number);
 163   if (value->IsAccessorPair()) {
 164     // TODO(verwaest): Currently details are always taken from the getter if it
 165     // is a transition, otherwise from the setter which in that case has to be a
 166     // transition. Details should be dependent on which component is requested.
 167     AccessorPair* accessors = AccessorPair::cast(value);
 168     if (accessors->getter()->IsMap()) {
 169       return Map::cast(accessors->getter());
 170     }
 171     return Map::cast(accessors->setter());
 172   }
 173   return Map::cast(value);
 174 }
 175
 176
 177 PropertyDetails TransitionArray::GetTargetDetails(int transition_number) {
 178   Map* map = GetTargetMap(transition_number);
 179   DescriptorArray* descriptors = map->instance_descriptors();
 180   int descriptor = descriptors->LastAdded();
 181   ASSERT(descriptor != DescriptorArray::kNotFound);
 182   return descriptors->GetDetails(descriptor);
 183 }
 184
 185
 186 Object** TransitionArray::GetElementsTransitionSlot() {
 187   return HeapObject::RawField(reinterpret_cast<HeapObject*>(this),
 188                               kElementsTransitionOffset);
 189 }
 190
 191
 192 int TransitionArray::Search(String* name) {
 193   return internal::Search(this, name);
 194 }
 195
 196
 197 void TransitionArray::Set(int transition_number,
 198                           String* key,
 199                           Object* value,
 200                           const WhitenessWitness&) {
 201   NoIncrementalWriteBarrierSet(this,
 202                                ToKeyIndex(transition_number),
 203                                key);
 204   NoIncrementalWriteBarrierSet(this,
 205                                ToValueIndex(transition_number),
 206                                value);
 207 }
 208
 209
 210 #undef FIELD_ADDR
 211 #undef WRITE_FIELD
 212 #undef CONDITIONAL_WRITE_BARRIER
 213
 214
 215 } }  // namespace v8::internal
 216
 217 #endif  // V8_TRANSITIONS_INL_H_