Fix and improve Map::CurrentMapForDeprecatedInternal().
Inline relevant bits from Map::FindUpdatedMap() and Map::IsMoreGeneralThan() into Map::CurrentMapForDeprecatedInternal() to fix issues introduced with field type tracking, avoid the useless second pass over the transition tree, and finally make it easier to understand what this method actually does. TEST=mjsunit/regress/regress-365172-2 R=svenpanne@chromium.org Committed: https://code.google.com/p/v8/source/detail?r=20997 Review URL: https://codereview.chromium.org/257893004 git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@21010 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This commit is contained in:
bmeurer@chromium.org
parent
5396d4e994
commit
15e0189c97
501
src/objects.cc
501
src/objects.cc
@ -2425,43 +2425,6 @@ Map* Map::FindRootMap() {
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}
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// Returns NULL if the updated map is incompatible.
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Map* Map::FindUpdatedMap(int verbatim,
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int length,
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DescriptorArray* descriptors) {
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DisallowHeapAllocation no_allocation;
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// This can only be called on roots of transition trees.
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ASSERT(GetBackPointer()->IsUndefined());
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Map* current = this;
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for (int i = verbatim; i < length; i++) {
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if (!current->HasTransitionArray()) break;
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Name* name = descriptors->GetKey(i);
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TransitionArray* transitions = current->transitions();
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int transition = transitions->Search(name);
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if (transition == TransitionArray::kNotFound) break;
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current = transitions->GetTarget(transition);
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PropertyDetails details = descriptors->GetDetails(i);
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PropertyDetails target_details =
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current->instance_descriptors()->GetDetails(i);
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if (details.attributes() != target_details.attributes()) return NULL;
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if (details.type() == CALLBACKS) {
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if (target_details.type() != CALLBACKS) return NULL;
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if (descriptors->GetValue(i) !=
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current->instance_descriptors()->GetValue(i)) {
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return NULL;
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}
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} else if (target_details.type() == CALLBACKS) {
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return NULL;
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}
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}
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return current;
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}
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Map* Map::FindLastMatchMap(int verbatim,
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int length,
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DescriptorArray* descriptors) {
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@ -2552,13 +2515,10 @@ void Map::GeneralizeFieldType(Handle<Map> map,
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int modify_index,
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Handle<HeapType> new_field_type) {
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Isolate* isolate = map->GetIsolate();
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Handle<Map> field_owner(map->FindFieldOwner(modify_index), isolate);
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Handle<DescriptorArray> descriptors(
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field_owner->instance_descriptors(), isolate);
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// Check if we actually need to generalize the field type at all.
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Handle<HeapType> old_field_type(
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descriptors->GetFieldType(modify_index), isolate);
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map->instance_descriptors()->GetFieldType(modify_index), isolate);
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if (new_field_type->NowIs(old_field_type)) {
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ASSERT(Map::GeneralizeFieldType(old_field_type,
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new_field_type,
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@ -2566,6 +2526,12 @@ void Map::GeneralizeFieldType(Handle<Map> map,
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return;
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}
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// Determine the field owner.
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Handle<Map> field_owner(map->FindFieldOwner(modify_index), isolate);
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Handle<DescriptorArray> descriptors(
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field_owner->instance_descriptors(), isolate);
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ASSERT_EQ(*old_field_type, descriptors->GetFieldType(modify_index));
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// Determine the generalized new field type.
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new_field_type = Map::GeneralizeFieldType(
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old_field_type, new_field_type, isolate);
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@ -2598,23 +2564,28 @@ void Map::GeneralizeFieldType(Handle<Map> map,
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// (partial) version of the type in the transition tree.
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// To do this, on each rewrite:
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// - Search the root of the transition tree using FindRootMap.
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// - Find |updated|, the newest matching version of this map using
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// FindUpdatedMap. This uses the keys in the own map's descriptor array to
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// walk the transition tree.
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// - Merge/generalize the descriptor array of the current map and |updated|.
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// - Generalize the |modify_index| descriptor using |new_representation|.
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// - Walk the tree again starting from the root towards |updated|. Stop at
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// - Find |target_map|, the newest matching version of this map using the keys
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// in the |old_map|'s descriptor array to walk the transition tree.
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// - Merge/generalize the descriptor array of the |old_map| and |target_map|.
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// - Generalize the |modify_index| descriptor using |new_representation| and
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// |new_field_type|.
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// - Walk the tree again starting from the root towards |target_map|. Stop at
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// |split_map|, the first map who's descriptor array does not match the merged
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// descriptor array.
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// - If |updated| == |split_map|, |updated| is in the expected state. Return it.
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// - Otherwise, invalidate the outdated transition target from |updated|, and
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// - If |target_map| == |split_map|, |target_map| is in the expected state.
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// Return it.
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// - Otherwise, invalidate the outdated transition target from |target_map|, and
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// replace its transition tree with a new branch for the updated descriptors.
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Handle<Map> Map::GeneralizeRepresentation(Handle<Map> old_map,
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int modify_index,
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Representation new_representation,
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Handle<HeapType> new_field_type,
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StoreMode store_mode) {
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Handle<DescriptorArray> old_descriptors(old_map->instance_descriptors());
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Isolate* isolate = old_map->GetIsolate();
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Handle<DescriptorArray> old_descriptors(
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old_map->instance_descriptors(), isolate);
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int old_nof = old_map->NumberOfOwnDescriptors();
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PropertyDetails old_details = old_descriptors->GetDetails(modify_index);
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Representation old_representation = old_details.representation();
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@ -2641,84 +2612,239 @@ Handle<Map> Map::GeneralizeRepresentation(Handle<Map> old_map,
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return old_map;
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}
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if (new_representation.Equals(old_representation) &&
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old_details.type() == FIELD) {
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Map::GeneralizeFieldType(old_map, modify_index, new_field_type);
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return old_map;
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}
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Handle<Map> root_map(old_map->FindRootMap());
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// Check the state of the root map.
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Handle<Map> root_map(old_map->FindRootMap(), isolate);
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if (!old_map->EquivalentToForTransition(*root_map)) {
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return CopyGeneralizeAllRepresentations(old_map, modify_index, store_mode,
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old_details.attributes(), "not equivalent");
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}
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int verbatim = root_map->NumberOfOwnDescriptors();
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if (store_mode != ALLOW_AS_CONSTANT && modify_index < verbatim) {
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return CopyGeneralizeAllRepresentations(old_map, modify_index, store_mode,
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old_details.attributes(), "root modification");
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int root_nof = root_map->NumberOfOwnDescriptors();
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if (modify_index < root_nof) {
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PropertyDetails old_details = old_descriptors->GetDetails(modify_index);
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if ((old_details.type() != FIELD && store_mode == FORCE_FIELD) ||
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(old_details.type() == FIELD &&
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(!new_field_type->NowIs(old_descriptors->GetFieldType(modify_index)) ||
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!new_representation.fits_into(old_details.representation())))) {
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return CopyGeneralizeAllRepresentations(old_map, modify_index, store_mode,
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old_details.attributes(), "root modification");
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}
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}
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int descriptors = old_map->NumberOfOwnDescriptors();
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Map* raw_updated = root_map->FindUpdatedMap(
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verbatim, descriptors, *old_descriptors);
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if (raw_updated == NULL) {
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return CopyGeneralizeAllRepresentations(old_map, modify_index, store_mode,
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old_details.attributes(), "incompatible");
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Handle<Map> target_map = root_map;
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for (int i = root_nof; i < old_nof; ++i) {
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int j = target_map->SearchTransition(old_descriptors->GetKey(i));
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if (j == TransitionArray::kNotFound) break;
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Handle<Map> tmp_map(target_map->GetTransition(j), isolate);
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Handle<DescriptorArray> tmp_descriptors = handle(
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tmp_map->instance_descriptors(), isolate);
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// Check if target map is incompatible.
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PropertyDetails old_details = old_descriptors->GetDetails(i);
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PropertyDetails tmp_details = tmp_descriptors->GetDetails(i);
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PropertyType old_type = old_details.type();
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PropertyType tmp_type = tmp_details.type();
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if (tmp_details.attributes() != old_details.attributes() ||
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((tmp_type == CALLBACKS || old_type == CALLBACKS) &&
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(tmp_type != old_type ||
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tmp_descriptors->GetValue(i) != old_descriptors->GetValue(i)))) {
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return CopyGeneralizeAllRepresentations(
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old_map, modify_index, store_mode,
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old_details.attributes(), "incompatible");
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}
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Representation old_representation = old_details.representation();
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Representation tmp_representation = tmp_details.representation();
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if (!old_representation.fits_into(tmp_representation) ||
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(!new_representation.fits_into(tmp_representation) &&
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modify_index == i)) {
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break;
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}
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if (tmp_type == FIELD) {
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// Generalize the field type as necessary.
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Handle<HeapType> old_field_type = (old_type == FIELD)
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? handle(old_descriptors->GetFieldType(i), isolate)
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: old_descriptors->GetValue(i)->OptimalType(
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isolate, tmp_representation);
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if (modify_index == i) {
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old_field_type = GeneralizeFieldType(
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new_field_type, old_field_type, isolate);
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}
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GeneralizeFieldType(tmp_map, i, old_field_type);
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} else if (tmp_type == CONSTANT) {
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if (old_type != CONSTANT ||
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old_descriptors->GetConstant(i) != tmp_descriptors->GetConstant(i)) {
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break;
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}
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} else {
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ASSERT_EQ(tmp_type, old_type);
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ASSERT_EQ(tmp_descriptors->GetValue(i), old_descriptors->GetValue(i));
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}
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target_map = tmp_map;
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}
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Handle<Map> updated(raw_updated);
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Handle<DescriptorArray> updated_descriptors(updated->instance_descriptors());
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int valid = updated->NumberOfOwnDescriptors();
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// Directly change the map if the target map is more general. Ensure that the
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// target type of the modify_index is a FIELD, unless we are migrating.
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if (updated_descriptors->IsMoreGeneralThan(
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verbatim, valid, descriptors, *old_descriptors) &&
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(store_mode == ALLOW_AS_CONSTANT ||
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updated_descriptors->GetDetails(modify_index).type() == FIELD)) {
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Representation updated_representation =
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updated_descriptors->GetDetails(modify_index).representation();
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if (new_representation.fits_into(updated_representation)) return updated;
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// Directly change the map if the target map is more general.
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Handle<DescriptorArray> target_descriptors(
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target_map->instance_descriptors(), isolate);
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int target_nof = target_map->NumberOfOwnDescriptors();
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if (target_nof == old_nof &&
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(store_mode != FORCE_FIELD ||
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target_descriptors->GetDetails(modify_index).type() == FIELD)) {
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ASSERT(modify_index < target_nof);
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ASSERT(new_representation.fits_into(
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target_descriptors->GetDetails(modify_index).representation()));
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ASSERT(target_descriptors->GetDetails(modify_index).type() != FIELD ||
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new_field_type->NowIs(
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target_descriptors->GetFieldType(modify_index)));
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return target_map;
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}
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Handle<DescriptorArray> new_descriptors = DescriptorArray::Merge(
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updated, verbatim, valid, descriptors, modify_index,
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store_mode, old_map);
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ASSERT(store_mode == ALLOW_AS_CONSTANT ||
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// Find the last compatible target map in the transition tree.
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for (int i = target_nof; i < old_nof; ++i) {
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int j = target_map->SearchTransition(old_descriptors->GetKey(i));
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if (j == TransitionArray::kNotFound) break;
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Handle<Map> tmp_map(target_map->GetTransition(j), isolate);
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Handle<DescriptorArray> tmp_descriptors(
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tmp_map->instance_descriptors(), isolate);
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// Check if target map is compatible.
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PropertyDetails old_details = old_descriptors->GetDetails(i);
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PropertyDetails tmp_details = tmp_descriptors->GetDetails(i);
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if (tmp_details.attributes() != old_details.attributes() ||
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((tmp_details.type() == CALLBACKS || old_details.type() == CALLBACKS) &&
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(tmp_details.type() != old_details.type() ||
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tmp_descriptors->GetValue(i) != old_descriptors->GetValue(i)))) {
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return CopyGeneralizeAllRepresentations(
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old_map, modify_index, store_mode,
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old_details.attributes(), "incompatible");
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}
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target_map = tmp_map;
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}
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target_nof = target_map->NumberOfOwnDescriptors();
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target_descriptors = handle(target_map->instance_descriptors(), isolate);
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// Allocate a new descriptor array large enough to hold the required
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// descriptors, with minimally the exact same size as the old descriptor
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// array.
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int new_slack = Max(
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old_nof, old_descriptors->number_of_descriptors()) - old_nof;
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Handle<DescriptorArray> new_descriptors = DescriptorArray::Allocate(
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isolate, old_nof, new_slack);
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ASSERT(new_descriptors->length() > target_descriptors->length() ||
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new_descriptors->NumberOfSlackDescriptors() > 0 ||
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new_descriptors->number_of_descriptors() ==
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old_descriptors->number_of_descriptors());
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ASSERT(new_descriptors->number_of_descriptors() == old_nof);
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// 0 -> |root_nof|
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int current_offset = 0;
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for (int i = 0; i < root_nof; ++i) {
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PropertyDetails old_details = old_descriptors->GetDetails(i);
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if (old_details.type() == FIELD) current_offset++;
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Descriptor d(handle(old_descriptors->GetKey(i), isolate),
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handle(old_descriptors->GetValue(i), isolate),
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old_details);
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new_descriptors->Set(i, &d);
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}
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// |root_nof| -> |target_nof|
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for (int i = root_nof; i < target_nof; ++i) {
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Handle<Name> target_key(target_descriptors->GetKey(i), isolate);
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PropertyDetails old_details = old_descriptors->GetDetails(i);
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PropertyDetails target_details = target_descriptors->GetDetails(i);
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target_details = target_details.CopyWithRepresentation(
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old_details.representation().generalize(
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target_details.representation()));
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if (modify_index == i) {
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target_details = target_details.CopyWithRepresentation(
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new_representation.generalize(target_details.representation()));
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}
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if (old_details.type() == FIELD ||
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target_details.type() == FIELD ||
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(modify_index == i && store_mode == FORCE_FIELD) ||
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(target_descriptors->GetValue(i) != old_descriptors->GetValue(i))) {
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Handle<HeapType> old_field_type = (old_details.type() == FIELD)
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? handle(old_descriptors->GetFieldType(i), isolate)
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: old_descriptors->GetValue(i)->OptimalType(
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isolate, target_details.representation());
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Handle<HeapType> target_field_type = (target_details.type() == FIELD)
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? handle(target_descriptors->GetFieldType(i), isolate)
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: target_descriptors->GetValue(i)->OptimalType(
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isolate, target_details.representation());
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target_field_type = GeneralizeFieldType(
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target_field_type, old_field_type, isolate);
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if (modify_index == i) {
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target_field_type = GeneralizeFieldType(
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target_field_type, new_field_type, isolate);
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}
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FieldDescriptor d(target_key,
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current_offset++,
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target_field_type,
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target_details.attributes(),
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target_details.representation());
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new_descriptors->Set(i, &d);
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} else {
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ASSERT_NE(FIELD, target_details.type());
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Descriptor d(target_key,
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handle(target_descriptors->GetValue(i), isolate),
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target_details);
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new_descriptors->Set(i, &d);
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}
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}
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// |target_nof| -> |old_nof|
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for (int i = target_nof; i < old_nof; ++i) {
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PropertyDetails old_details = old_descriptors->GetDetails(i);
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Handle<Name> old_key(old_descriptors->GetKey(i), isolate);
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if (modify_index == i) {
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old_details = old_details.CopyWithRepresentation(
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new_representation.generalize(old_details.representation()));
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}
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if (old_details.type() == FIELD) {
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Handle<HeapType> old_field_type(
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old_descriptors->GetFieldType(i), isolate);
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if (modify_index == i) {
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old_field_type = GeneralizeFieldType(
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old_field_type, new_field_type, isolate);
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}
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FieldDescriptor d(old_key,
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current_offset++,
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old_field_type,
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old_details.attributes(),
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old_details.representation());
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new_descriptors->Set(i, &d);
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} else {
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ASSERT(old_details.type() == CONSTANT || old_details.type() == CALLBACKS);
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if (modify_index == i && store_mode == FORCE_FIELD) {
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FieldDescriptor d(old_key,
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current_offset++,
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GeneralizeFieldType(
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old_descriptors->GetValue(i)->OptimalType(
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isolate, old_details.representation()),
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new_field_type, isolate),
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old_details.attributes(),
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old_details.representation());
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new_descriptors->Set(i, &d);
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} else {
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ASSERT_NE(FIELD, old_details.type());
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Descriptor d(old_key,
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handle(old_descriptors->GetValue(i), isolate),
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old_details);
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new_descriptors->Set(i, &d);
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}
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}
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}
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new_descriptors->Sort();
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ASSERT(store_mode != FORCE_FIELD ||
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new_descriptors->GetDetails(modify_index).type() == FIELD);
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Isolate* isolate = new_descriptors->GetIsolate();
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old_representation =
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new_descriptors->GetDetails(modify_index).representation();
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Representation updated_representation =
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new_representation.generalize(old_representation);
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if (!updated_representation.Equals(old_representation)) {
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new_descriptors->SetRepresentation(modify_index, updated_representation);
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}
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if (new_descriptors->GetDetails(modify_index).type() == FIELD) {
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Handle<HeapType> field_type(
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new_descriptors->GetFieldType(modify_index), isolate);
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new_field_type = Map::GeneralizeFieldType(
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field_type, new_field_type, isolate);
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new_descriptors->SetValue(modify_index, *new_field_type);
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}
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Handle<Map> split_map(root_map->FindLastMatchMap(
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verbatim, descriptors, *new_descriptors));
|
||||
root_nof, old_nof, *new_descriptors), isolate);
|
||||
int split_nof = split_map->NumberOfOwnDescriptors();
|
||||
ASSERT_NE(old_nof, split_nof);
|
||||
|
||||
int split_descriptors = split_map->NumberOfOwnDescriptors();
|
||||
// This is shadowed by |updated_descriptors| being more general than
|
||||
// |old_descriptors|.
|
||||
ASSERT(descriptors != split_descriptors);
|
||||
|
||||
int descriptor = split_descriptors;
|
||||
split_map->DeprecateTarget(
|
||||
old_descriptors->GetKey(descriptor), *new_descriptors);
|
||||
old_descriptors->GetKey(split_nof), *new_descriptors);
|
||||
|
||||
if (FLAG_trace_generalization) {
|
||||
PropertyDetails old_details = old_descriptors->GetDetails(modify_index);
|
||||
@ -2732,7 +2858,7 @@ Handle<Map> Map::GeneralizeRepresentation(Handle<Map> old_map,
|
||||
: HeapType::Constant(handle(new_descriptors->GetValue(modify_index),
|
||||
isolate), isolate);
|
||||
old_map->PrintGeneralization(
|
||||
stdout, "", modify_index, descriptor, descriptors,
|
||||
stdout, "", modify_index, split_nof, old_nof,
|
||||
old_details.type() == CONSTANT && store_mode == FORCE_FIELD,
|
||||
old_details.representation(), new_details.representation(),
|
||||
*old_field_type, *new_field_type);
|
||||
@ -2740,10 +2866,9 @@ Handle<Map> Map::GeneralizeRepresentation(Handle<Map> old_map,
|
||||
|
||||
// Add missing transitions.
|
||||
Handle<Map> new_map = split_map;
|
||||
for (; descriptor < descriptors; descriptor++) {
|
||||
new_map = CopyInstallDescriptors(new_map, descriptor, new_descriptors);
|
||||
for (int i = split_nof; i < old_nof; ++i) {
|
||||
new_map = CopyInstallDescriptors(new_map, i, new_descriptors);
|
||||
}
|
||||
|
||||
new_map->set_owns_descriptors(true);
|
||||
return new_map;
|
||||
}
|
||||
@ -8397,150 +8522,6 @@ void DescriptorArray::CopyFrom(int index,
|
||||
}
|
||||
|
||||
|
||||
// Creates a new descriptor array by merging the descriptor array of |right_map|
|
||||
// into the (at least partly) updated descriptor array of |left_map|.
|
||||
// The method merges two descriptor array in three parts. Both descriptor arrays
|
||||
// are identical up to |verbatim|. They also overlap in keys up to |valid|.
|
||||
// Between |verbatim| and |valid|, the resulting descriptor type as well as the
|
||||
// representation are generalized from both |left_map| and |right_map|. Beyond
|
||||
// |valid|, the descriptors are copied verbatim from |right_map| up to
|
||||
// |new_size|.
|
||||
// In case of incompatible types, the type and representation of |right_map| is
|
||||
// used.
|
||||
Handle<DescriptorArray> DescriptorArray::Merge(Handle<Map> left_map,
|
||||
int verbatim,
|
||||
int valid,
|
||||
int new_size,
|
||||
int modify_index,
|
||||
StoreMode store_mode,
|
||||
Handle<Map> right_map) {
|
||||
ASSERT(verbatim <= valid);
|
||||
ASSERT(valid <= new_size);
|
||||
|
||||
// Allocate a new descriptor array large enough to hold the required
|
||||
// descriptors, with minimally the exact same size as this descriptor array.
|
||||
Isolate* isolate = left_map->GetIsolate();
|
||||
Handle<DescriptorArray> left(left_map->instance_descriptors());
|
||||
Handle<DescriptorArray> right(right_map->instance_descriptors());
|
||||
Handle<DescriptorArray> result = DescriptorArray::Allocate(
|
||||
isolate,
|
||||
new_size,
|
||||
Max(new_size, right->number_of_descriptors()) - new_size);
|
||||
ASSERT(result->length() > left->length() ||
|
||||
result->NumberOfSlackDescriptors() > 0 ||
|
||||
result->number_of_descriptors() == right->number_of_descriptors());
|
||||
ASSERT(result->number_of_descriptors() == new_size);
|
||||
|
||||
int descriptor;
|
||||
|
||||
// 0 -> |verbatim|
|
||||
int current_offset = 0;
|
||||
for (descriptor = 0; descriptor < verbatim; descriptor++) {
|
||||
if (left->GetDetails(descriptor).type() == FIELD) current_offset++;
|
||||
Descriptor d(handle(right->GetKey(descriptor)),
|
||||
handle(right->GetValue(descriptor), right->GetIsolate()),
|
||||
right->GetDetails(descriptor));
|
||||
result->Set(descriptor, &d);
|
||||
}
|
||||
|
||||
// |verbatim| -> |valid|
|
||||
for (; descriptor < valid; descriptor++) {
|
||||
PropertyDetails left_details = left->GetDetails(descriptor);
|
||||
PropertyDetails right_details = right->GetDetails(descriptor);
|
||||
if (left_details.type() == FIELD || right_details.type() == FIELD ||
|
||||
(store_mode == FORCE_FIELD && descriptor == modify_index) ||
|
||||
(left_details.type() == CONSTANT &&
|
||||
right_details.type() == CONSTANT &&
|
||||
left->GetValue(descriptor) != right->GetValue(descriptor))) {
|
||||
ASSERT(left_details.type() == CONSTANT || left_details.type() == FIELD);
|
||||
ASSERT(right_details.type() == CONSTANT || right_details.type() == FIELD);
|
||||
Representation representation = left_details.representation().generalize(
|
||||
right_details.representation());
|
||||
Handle<HeapType> left_type = (left_details.type() == FIELD)
|
||||
? handle(left->GetFieldType(descriptor), isolate)
|
||||
: left->GetValue(descriptor)->OptimalType(isolate, representation);
|
||||
Handle<HeapType> right_type = (right_details.type() == FIELD)
|
||||
? handle(right->GetFieldType(descriptor), isolate)
|
||||
: right->GetValue(descriptor)->OptimalType(isolate, representation);
|
||||
Handle<HeapType> field_type = Map::GeneralizeFieldType(
|
||||
left_type, right_type, isolate);
|
||||
FieldDescriptor d(handle(left->GetKey(descriptor), isolate),
|
||||
current_offset++,
|
||||
field_type,
|
||||
right_details.attributes(),
|
||||
representation);
|
||||
result->Set(descriptor, &d);
|
||||
} else {
|
||||
Descriptor d(handle(right->GetKey(descriptor), isolate),
|
||||
handle(right->GetValue(descriptor), isolate),
|
||||
right_details);
|
||||
result->Set(descriptor, &d);
|
||||
}
|
||||
}
|
||||
|
||||
// |valid| -> |new_size|
|
||||
for (; descriptor < new_size; descriptor++) {
|
||||
PropertyDetails right_details = right->GetDetails(descriptor);
|
||||
if (right_details.type() == FIELD) {
|
||||
FieldDescriptor d(handle(right->GetKey(descriptor), isolate),
|
||||
current_offset++,
|
||||
handle(right->GetFieldType(descriptor), isolate),
|
||||
right_details.attributes(),
|
||||
right_details.representation());
|
||||
result->Set(descriptor, &d);
|
||||
} else if (store_mode == FORCE_FIELD && descriptor == modify_index) {
|
||||
ASSERT_EQ(CONSTANT, right_details.type());
|
||||
Representation field_representation = right_details.representation();
|
||||
Handle<HeapType> field_type = right->GetValue(descriptor)->OptimalType(
|
||||
isolate, field_representation);
|
||||
FieldDescriptor d(handle(right->GetKey(descriptor), isolate),
|
||||
current_offset++,
|
||||
field_type,
|
||||
right_details.attributes(),
|
||||
field_representation);
|
||||
result->Set(descriptor, &d);
|
||||
} else {
|
||||
Descriptor d(handle(right->GetKey(descriptor), isolate),
|
||||
handle(right->GetValue(descriptor), isolate),
|
||||
right_details);
|
||||
result->Set(descriptor, &d);
|
||||
}
|
||||
}
|
||||
|
||||
result->Sort();
|
||||
return result;
|
||||
}
|
||||
|
||||
|
||||
// Checks whether a merge of |other| into |this| would return a copy of |this|.
|
||||
bool DescriptorArray::IsMoreGeneralThan(int verbatim,
|
||||
int valid,
|
||||
int new_size,
|
||||
DescriptorArray* other) {
|
||||
ASSERT(verbatim <= valid);
|
||||
ASSERT(valid <= new_size);
|
||||
if (valid != new_size) return false;
|
||||
|
||||
for (int descriptor = verbatim; descriptor < valid; descriptor++) {
|
||||
PropertyDetails details = GetDetails(descriptor);
|
||||
PropertyDetails other_details = other->GetDetails(descriptor);
|
||||
if (!other_details.representation().fits_into(details.representation())) {
|
||||
return false;
|
||||
}
|
||||
if (details.type() == CONSTANT) {
|
||||
if (other_details.type() != CONSTANT) return false;
|
||||
if (GetValue(descriptor) != other->GetValue(descriptor)) return false;
|
||||
} else if (details.type() == FIELD && other_details.type() == FIELD) {
|
||||
if (!other->GetFieldType(descriptor)->NowIs(GetFieldType(descriptor))) {
|
||||
return false;
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
return true;
|
||||
}
|
||||
|
||||
|
||||
// We need the whiteness witness since sort will reshuffle the entries in the
|
||||
// descriptor array. If the descriptor array were to be black, the shuffling
|
||||
// would move a slot that was already recorded as pointing into an evacuation
|
||||
|
||||
@ -3441,20 +3441,6 @@ class DescriptorArray: public FixedArray {
|
||||
// array.
|
||||
inline void Append(Descriptor* desc);
|
||||
|
||||
static Handle<DescriptorArray> Merge(Handle<Map> left_map,
|
||||
int verbatim,
|
||||
int valid,
|
||||
int new_size,
|
||||
int modify_index,
|
||||
StoreMode store_mode,
|
||||
Handle<Map> right_map)
|
||||
V8_WARN_UNUSED_RESULT;
|
||||
|
||||
bool IsMoreGeneralThan(int verbatim,
|
||||
int valid,
|
||||
int new_size,
|
||||
DescriptorArray* other);
|
||||
|
||||
static Handle<DescriptorArray> CopyUpTo(Handle<DescriptorArray> desc,
|
||||
int enumeration_index,
|
||||
int slack = 0);
|
||||
@ -6733,7 +6719,6 @@ class Map: public HeapObject {
|
||||
void DeprecateTransitionTree();
|
||||
void DeprecateTarget(Name* key, DescriptorArray* new_descriptors);
|
||||
|
||||
Map* FindUpdatedMap(int verbatim, int length, DescriptorArray* descriptors);
|
||||
Map* FindLastMatchMap(int verbatim, int length, DescriptorArray* descriptors);
|
||||
|
||||
void UpdateDescriptor(int descriptor_number, Descriptor* desc);
|
||||
|
||||
@ -66,6 +66,7 @@ class Descriptor BASE_EMBEDDED {
|
||||
details_(attributes, type, representation, field_index) { }
|
||||
|
||||
friend class DescriptorArray;
|
||||
friend class Map;
|
||||
};
|
||||
|
||||
|
||||
|
||||
Loading…
Reference in New Issue
Block a user