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// Copyright 2015 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#ifndef V8_COMPILER_ACCESS_INFO_H_
#define V8_COMPILER_ACCESS_INFO_H_
#include <iosfwd>
#include "src/compiler/types.h"
#include "src/feedback-vector.h"
#include "src/field-index.h"
#include "src/machine-type.h"
#include "src/objects.h"
#include "src/objects/map.h"
#include "src/zone/zone-containers.h"
namespace v8 {
namespace internal {
// Forward declarations.
class Factory;
namespace compiler {
// Forward declarations.
class CompilationDependencies;
class Type;
class TypeCache;
struct ProcessedFeedback;
// Whether we are loading a property or storing to a property.
// For a store during literal creation, do not walk up the prototype chain.
enum class AccessMode { kLoad, kStore, kStoreInLiteral, kHas };
std::ostream& operator<<(std::ostream&, AccessMode);
// This class encapsulates all information required to access a certain element.
class ElementAccessInfo final {
public:
ElementAccessInfo();
ElementAccessInfo(MapHandles const& receiver_maps,
ElementsKind elements_kind);
ElementsKind elements_kind() const { return elements_kind_; }
MapHandles const& receiver_maps() const { return receiver_maps_; }
MapHandles const& transition_sources() const { return transition_sources_; }
void AddTransitionSource(Handle<Map> map) {
CHECK_EQ(receiver_maps_.size(), 1);
transition_sources_.push_back(map);
}
private:
ElementsKind elements_kind_;
MapHandles receiver_maps_;
MapHandles transition_sources_;
};
// This class encapsulates all information required to access a certain
// object property, either on the object itself or on the prototype chain.
class PropertyAccessInfo final {
public:
enum Kind {
kInvalid,
kNotFound,
kDataConstant,
kDataField,
kDataConstantField,
kAccessorConstant,
kModuleExport,
kStringLength
};
static PropertyAccessInfo NotFound(MapHandles const& receiver_maps,
MaybeHandle<JSObject> holder);
static PropertyAccessInfo DataConstant(MapHandles const& receiver_maps,
Handle<Object> constant,
MaybeHandle<JSObject> holder);
static PropertyAccessInfo DataField(
PropertyConstness constness, MapHandles const& receiver_maps,
FieldIndex field_index, MachineRepresentation field_representation,
Type field_type, MaybeHandle<Map> field_map = MaybeHandle<Map>(),
MaybeHandle<JSObject> holder = MaybeHandle<JSObject>(),
MaybeHandle<Map> transition_map = MaybeHandle<Map>());
static PropertyAccessInfo AccessorConstant(MapHandles const& receiver_maps,
Handle<Object> constant,
MaybeHandle<JSObject> holder);
static PropertyAccessInfo ModuleExport(MapHandles const& receiver_maps,
Handle<Cell> cell);
static PropertyAccessInfo StringLength(MapHandles const& receiver_maps);
PropertyAccessInfo();
bool Merge(PropertyAccessInfo const* that, AccessMode access_mode,
Zone* zone) V8_WARN_UNUSED_RESULT;
bool IsNotFound() const { return kind() == kNotFound; }
bool IsDataConstant() const { return kind() == kDataConstant; }
bool IsDataField() const { return kind() == kDataField; }
// TODO(ishell): rename to IsDataConstant() once constant field tracking
// is done.
bool IsDataConstantField() const { return kind() == kDataConstantField; }
bool IsAccessorConstant() const { return kind() == kAccessorConstant; }
bool IsModuleExport() const { return kind() == kModuleExport; }
bool IsStringLength() const { return kind() == kStringLength; }
bool HasTransitionMap() const { return !transition_map().is_null(); }
Kind kind() const { return kind_; }
MaybeHandle<JSObject> holder() const { return holder_; }
MaybeHandle<Map> transition_map() const { return transition_map_; }
Handle<Object> constant() const { return constant_; }
FieldIndex field_index() const { return field_index_; }
Type field_type() const { return field_type_; }
MachineRepresentation field_representation() const {
return field_representation_;
}
MaybeHandle<Map> field_map() const { return field_map_; }
MapHandles const& receiver_maps() const { return receiver_maps_; }
Handle<Cell> export_cell() const;
private:
PropertyAccessInfo(Kind kind, MaybeHandle<JSObject> holder,
MapHandles const& receiver_maps);
PropertyAccessInfo(Kind kind, MaybeHandle<JSObject> holder,
Handle<Object> constant, MapHandles const& receiver_maps);
PropertyAccessInfo(Kind kind, MaybeHandle<JSObject> holder,
MaybeHandle<Map> transition_map, FieldIndex field_index,
MachineRepresentation field_representation,
Type field_type, MaybeHandle<Map> field_map,
MapHandles const& receiver_maps);
Kind kind_;
MapHandles receiver_maps_;
Handle<Object> constant_;
MaybeHandle<Map> transition_map_;
MaybeHandle<JSObject> holder_;
FieldIndex field_index_;
MachineRepresentation field_representation_;
Type field_type_;
MaybeHandle<Map> field_map_;
};
// Factory class for {ElementAccessInfo}s and {PropertyAccessInfo}s.
class AccessInfoFactory final {
public:
AccessInfoFactory(JSHeapBroker* broker, CompilationDependencies* dependencies,
Zone* zone);
bool ComputeElementAccessInfo(Handle<Map> map, AccessMode access_mode,
ElementAccessInfo* access_info) const;
bool ComputeElementAccessInfos(
FeedbackNexus nexus, MapHandles const& maps, AccessMode access_mode,
ZoneVector<ElementAccessInfo>* access_infos) const;
bool ComputePropertyAccessInfo(Handle<Map> map, Handle<Name> name,
AccessMode access_mode,
PropertyAccessInfo* access_info) const;
bool ComputePropertyAccessInfo(MapHandles const& maps, Handle<Name> name,
AccessMode access_mode,
PropertyAccessInfo* access_info) const;
bool ComputePropertyAccessInfos(
MapHandles const& maps, Handle<Name> name, AccessMode access_mode,
ZoneVector<PropertyAccessInfo>* access_infos) const;
private:
bool ConsolidateElementLoad(ProcessedFeedback const& processed,
ElementAccessInfo* access_info) const;
bool LookupSpecialFieldAccessor(Handle<Map> map, Handle<Name> name,
PropertyAccessInfo* access_info) const;
bool LookupTransition(Handle<Map> map, Handle<Name> name,
MaybeHandle<JSObject> holder,
PropertyAccessInfo* access_info) const;
bool ComputeDataFieldAccessInfo(Handle<Map> receiver_map, Handle<Map> map,
MaybeHandle<JSObject> holder, int number,
AccessMode access_mode,
PropertyAccessInfo* access_info) const;
bool ComputeAccessorDescriptorAccessInfo(
Handle<Map> receiver_map, Handle<Name> name, Handle<Map> map,
MaybeHandle<JSObject> holder, int number, AccessMode access_mode,
PropertyAccessInfo* access_info) const;
CompilationDependencies* dependencies() const { return dependencies_; }
JSHeapBroker* broker() const { return broker_; }
Isolate* isolate() const { return broker()->isolate(); }
Zone* zone() const { return zone_; }
JSHeapBroker* const broker_;
CompilationDependencies* const dependencies_;
TypeCache const* const type_cache_;
Zone* const zone_;
DISALLOW_COPY_AND_ASSIGN(AccessInfoFactory);
};
} // namespace compiler
} // namespace internal
} // namespace v8
#endif // V8_COMPILER_ACCESS_INFO_H_
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