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// Copyright 2018 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.
#include "src/base/compiler-specific.h"
#include "src/base/optional.h"
#include "src/compiler/refs-map.h"
#include "src/feedback-vector.h"
#include "src/function-kind.h"
#include "src/globals.h"
#include "src/handles.h"
#include "src/objects.h"
#include "src/objects/instance-type.h"
#include "src/ostreams.h"
#include "src/zone/zone-containers.h"
namespace v8 {
namespace internal {
class BytecodeArray;
class CallHandlerInfo;
class FixedDoubleArray;
class FunctionTemplateInfo;
class HeapNumber;
class InternalizedString;
class JSBoundFunction;
class JSDataView;
class JSGlobalProxy;
class JSRegExp;
class JSTypedArray;
class NativeContext;
class ScriptContextTable;
class VectorSlotPair;
namespace compiler {
// 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 };
enum class OddballType : uint8_t {
kNone, // Not an Oddball.
kBoolean, // True or False.
kOther // Oddball, but none of the above.
// This list is sorted such that subtypes appear before their supertypes.
/* Subtypes of JSObject */ \
V(JSArray) \
V(JSBoundFunction) \
V(JSDataView) \
V(JSFunction) \
V(JSGlobalProxy) \
V(JSRegExp) \
V(JSTypedArray) \
/* Subtypes of Context */ \
V(NativeContext) \
/* Subtypes of FixedArray */ \
V(Context) \
V(ScopeInfo) \
V(ScriptContextTable) \
/* Subtypes of FixedArrayBase */ \
V(BytecodeArray) \
V(FixedArray) \
V(FixedDoubleArray) \
/* Subtypes of Name */ \
V(InternalizedString) \
V(String) \
V(Symbol) \
/* Subtypes of HeapObject */ \
V(AllocationSite) \
V(CallHandlerInfo) \
V(Cell) \
V(Code) \
V(DescriptorArray) \
V(FeedbackCell) \
V(FeedbackVector) \
V(FixedArrayBase) \
V(FunctionTemplateInfo) \
V(HeapNumber) \
V(JSObject) \
V(Map) \
V(Module) \
V(MutableHeapNumber) \
V(Name) \
V(PropertyCell) \
V(SharedFunctionInfo) \
/* Subtypes of Object */ \
class CompilationDependencies;
class JSHeapBroker;
class ObjectData;
class PerIsolateCompilerCache;
class PropertyAccessInfo;
#define FORWARD_DECL(Name) class Name##Ref;
class V8_EXPORT_PRIVATE ObjectRef {
ObjectRef(JSHeapBroker* broker, Handle<Object> object);
ObjectRef(JSHeapBroker* broker, ObjectData* data)
: data_(data), broker_(broker) {
Handle<Object> object() const;
bool equals(const ObjectRef& other) const;
bool IsSmi() const;
int AsSmi() const;
#define HEAP_IS_METHOD_DECL(Name) bool Is##Name() const;
#define HEAP_AS_METHOD_DECL(Name) Name##Ref As##Name() const;
bool IsNullOrUndefined() const;
bool BooleanValue() const;
Maybe<double> OddballToNumber() const;
// Return the element at key {index} if {index} is known to be an own data
// property of the object that is non-writable and non-configurable.
base::Optional<ObjectRef> GetOwnConstantElement(uint32_t index,
bool serialize = false) const;
Isolate* isolate() const;
JSHeapBroker* broker() const;
ObjectData* data() const;
ObjectData* data_; // Should be used only by object() getters.
friend class JSArrayData;
friend class JSGlobalProxyRef;
friend class JSGlobalProxyData;
friend class JSObjectData;
friend class StringData;
friend std::ostream& operator<<(std::ostream& os, const ObjectRef& ref);
JSHeapBroker* broker_;
std::ostream& operator<<(std::ostream& os, const ObjectRef& ref);
// Temporary class that carries information from a Map. We'd like to remove
// this class and use MapRef instead, but we can't as long as we support the
// kDisabled broker mode. That's because obtaining the MapRef via
// HeapObjectRef::map() requires a HandleScope when the broker is disabled.
// During OptimizeGraph we generally don't have a HandleScope, however. There
// are two places where we therefore use GetHeapObjectType() instead. Both that
// function and this class should eventually be removed.
class HeapObjectType {
enum Flag : uint8_t { kUndetectable = 1 << 0, kCallable = 1 << 1 };
using Flags = base::Flags<Flag>;
HeapObjectType(InstanceType instance_type, Flags flags,
OddballType oddball_type)
: instance_type_(instance_type),
flags_(flags) {
DCHECK_EQ(instance_type == ODDBALL_TYPE,
oddball_type != OddballType::kNone);
OddballType oddball_type() const { return oddball_type_; }
InstanceType instance_type() const { return instance_type_; }
Flags flags() const { return flags_; }
bool is_callable() const { return flags_ & kCallable; }
bool is_undetectable() const { return flags_ & kUndetectable; }
InstanceType const instance_type_;
OddballType const oddball_type_;
Flags const flags_;
class HeapObjectRef : public ObjectRef {
using ObjectRef::ObjectRef;
Handle<HeapObject> object() const;
MapRef map() const;
// See the comment on the HeapObjectType class.
HeapObjectType GetHeapObjectType() const;
class PropertyCellRef : public HeapObjectRef {
using HeapObjectRef::HeapObjectRef;
Handle<PropertyCell> object() const;
PropertyDetails property_details() const;
void Serialize();
ObjectRef value() const;
class JSObjectRef : public HeapObjectRef {
using HeapObjectRef::HeapObjectRef;
Handle<JSObject> object() const;
double RawFastDoublePropertyAt(FieldIndex index) const;
ObjectRef RawFastPropertyAt(FieldIndex index) const;
FixedArrayBaseRef elements() const;
void EnsureElementsTenured();
ElementsKind GetElementsKind() const;
void SerializeObjectCreateMap();
base::Optional<MapRef> GetObjectCreateMap() const;
class JSDataViewRef : public JSObjectRef {
using JSObjectRef::JSObjectRef;
Handle<JSDataView> object() const;
size_t byte_length() const;
size_t byte_offset() const;
class JSBoundFunctionRef : public JSObjectRef {
using JSObjectRef::JSObjectRef;
Handle<JSBoundFunction> object() const;
void Serialize();
// The following are available only after calling Serialize().
ObjectRef bound_target_function() const;
ObjectRef bound_this() const;
FixedArrayRef bound_arguments() const;
class V8_EXPORT_PRIVATE JSFunctionRef : public JSObjectRef {
using JSObjectRef::JSObjectRef;
Handle<JSFunction> object() const;
bool has_feedback_vector() const;
bool has_initial_map() const;
bool has_prototype() const;
bool PrototypeRequiresRuntimeLookup() const;
void Serialize();
bool serialized() const;
// The following are available only after calling Serialize().
ObjectRef prototype() const;
MapRef initial_map() const;
ContextRef context() const;
NativeContextRef native_context() const;
SharedFunctionInfoRef shared() const;
FeedbackVectorRef feedback_vector() const;
int InitialMapInstanceSizeWithMinSlack() const;
bool IsSerializedForCompilation() const;
class JSRegExpRef : public JSObjectRef {
using JSObjectRef::JSObjectRef;
Handle<JSRegExp> object() const;
ObjectRef raw_properties_or_hash() const;
ObjectRef data() const;
ObjectRef source() const;
ObjectRef flags() const;
ObjectRef last_index() const;
class HeapNumberRef : public HeapObjectRef {
using HeapObjectRef::HeapObjectRef;
Handle<HeapNumber> object() const;
double value() const;
class MutableHeapNumberRef : public HeapObjectRef {
using HeapObjectRef::HeapObjectRef;
Handle<MutableHeapNumber> object() const;
double value() const;
class ContextRef : public HeapObjectRef {
using HeapObjectRef::HeapObjectRef;
Handle<Context> object() const;
void SerializeContextChain();
ContextRef previous() const;
void SerializeSlot(int index);
ObjectRef get(int index) const;
V(JSFunction, array_function) \
V(JSFunction, boolean_function) \
V(JSFunction, bigint_function) \
V(JSFunction, number_function) \
V(JSFunction, object_function) \
V(JSFunction, promise_function) \
V(JSFunction, promise_then) \
V(JSFunction, string_function) \
V(JSFunction, symbol_function) \
V(JSGlobalProxy, global_proxy_object) \
V(JSObject, promise_prototype) \
V(Map, bound_function_with_constructor_map) \
V(Map, bound_function_without_constructor_map) \
V(Map, fast_aliased_arguments_map) \
V(Map, initial_array_iterator_map) \
V(Map, initial_string_iterator_map) \
V(Map, iterator_result_map) \
V(Map, js_array_holey_double_elements_map) \
V(Map, js_array_holey_elements_map) \
V(Map, js_array_holey_smi_elements_map) \
V(Map, js_array_packed_double_elements_map) \
V(Map, js_array_packed_elements_map) \
V(Map, js_array_packed_smi_elements_map) \
V(Map, sloppy_arguments_map) \
V(Map, slow_object_with_null_prototype_map) \
V(Map, strict_arguments_map) \
V(ScriptContextTable, script_context_table) \
V(SharedFunctionInfo, promise_capability_default_reject_shared_fun) \
V(SharedFunctionInfo, promise_catch_finally_shared_fun) \
V(SharedFunctionInfo, promise_then_finally_shared_fun) \
V(SharedFunctionInfo, promise_capability_default_resolve_shared_fun)
// Those are set by Bootstrapper::ExportFromRuntime, which may not yet have
// happened when Turbofan is invoked via --always-opt.
V(Map, async_function_object_map) \
V(Map, map_key_iterator_map) \
V(Map, map_key_value_iterator_map) \
V(Map, map_value_iterator_map) \
V(Map, set_key_value_iterator_map) \
V(Map, set_value_iterator_map)
class NativeContextRef : public ContextRef {
using ContextRef::ContextRef;
Handle<NativeContext> object() const;
void Serialize();
#define DECL_ACCESSOR(type, name) type##Ref name() const;
MapRef GetFunctionMapFromIndex(int index) const;
MapRef GetInitialJSArrayMap(ElementsKind kind) const;
base::Optional<JSFunctionRef> GetConstructorFunction(const MapRef& map) const;
class NameRef : public HeapObjectRef {
using HeapObjectRef::HeapObjectRef;
Handle<Name> object() const;
bool IsUniqueName() const;
class ScriptContextTableRef : public HeapObjectRef {
using HeapObjectRef::HeapObjectRef;
Handle<ScriptContextTable> object() const;
struct LookupResult {
ContextRef context;
bool immutable;
int index;
base::Optional<LookupResult> lookup(const NameRef& name) const;
class DescriptorArrayRef : public HeapObjectRef {
using HeapObjectRef::HeapObjectRef;
Handle<DescriptorArray> object() const;
class FeedbackCellRef : public HeapObjectRef {
using HeapObjectRef::HeapObjectRef;
Handle<FeedbackCell> object() const;
HeapObjectRef value() const;
class FeedbackVectorRef : public HeapObjectRef {
using HeapObjectRef::HeapObjectRef;
Handle<FeedbackVector> object() const;
ObjectRef get(FeedbackSlot slot) const;
void SerializeSlots();
class FunctionTemplateInfoRef : public HeapObjectRef {
using HeapObjectRef::HeapObjectRef;
Handle<FunctionTemplateInfo> object() const;
void Serialize();
ObjectRef call_code() const;
class CallHandlerInfoRef : public HeapObjectRef {
using HeapObjectRef::HeapObjectRef;
Handle<CallHandlerInfo> object() const;
Address callback() const;
void Serialize();
ObjectRef data() const;
class AllocationSiteRef : public HeapObjectRef {
using HeapObjectRef::HeapObjectRef;
Handle<AllocationSite> object() const;
bool PointsToLiteral() const;
AllocationType GetAllocationType() const;
ObjectRef nested_site() const;
// {IsFastLiteral} determines whether the given array or object literal
// boilerplate satisfies all limits to be considered for fast deep-copying
// and computes the total size of all objects that are part of the graph.
// If PointsToLiteral() is false, then IsFastLiteral() is also false.
bool IsFastLiteral() const;
// We only serialize boilerplate if IsFastLiteral is true.
base::Optional<JSObjectRef> boilerplate() const;
ElementsKind GetElementsKind() const;
bool CanInlineCall() const;
class V8_EXPORT_PRIVATE MapRef : public HeapObjectRef {
using HeapObjectRef::HeapObjectRef;
Handle<Map> object() const;
int instance_size() const;
InstanceType instance_type() const;
int GetInObjectProperties() const;
int GetInObjectPropertiesStartInWords() const;
int NumberOfOwnDescriptors() const;
int GetInObjectPropertyOffset(int index) const;
int constructor_function_index() const;
int NextFreePropertyIndex() const;
int UnusedPropertyFields() const;
ElementsKind elements_kind() const;
bool is_stable() const;
bool is_extensible() const;
bool is_constructor() const;
bool has_prototype_slot() const;
bool is_access_check_needed() const;
bool is_deprecated() const;
bool CanBeDeprecated() const;
bool CanTransition() const;
bool IsInobjectSlackTrackingInProgress() const;
bool is_dictionary_map() const;
bool IsFixedCowArrayMap() const;
bool IsPrimitiveMap() const;
bool is_undetectable() const;
bool is_callable() const;
bool has_indexed_interceptor() const;
bool has_hidden_prototype() const;
bool is_migration_target() const;
bool supports_fast_array_iteration() const;
bool supports_fast_array_resize() const;
bool IsMapOfCurrentGlobalProxy() const;
OddballType oddball_type() const;
#define DEF_TESTER(Type, ...) bool Is##Type##Map() const;
void SerializeBackPointer();
HeapObjectRef GetBackPointer() const;
void SerializePrototype();
bool serialized_prototype() const;
HeapObjectRef prototype() const;
void SerializeForElementLoad();
void SerializeForElementStore();
bool HasOnlyStablePrototypesWithFastElements(
ZoneVector<MapRef>* prototype_maps);
// Concerning the underlying instance_descriptors:
void SerializeOwnDescriptors();
void SerializeOwnDescriptor(int descriptor_index);
MapRef FindFieldOwner(int descriptor_index) const;
PropertyDetails GetPropertyDetails(int descriptor_index) const;
NameRef GetPropertyKey(int descriptor_index) const;
FieldIndex GetFieldIndexFor(int descriptor_index) const;
ObjectRef GetFieldType(int descriptor_index) const;
bool IsUnboxedDoubleField(int descriptor_index) const;
// Available after calling JSFunctionRef::Serialize on a function that has
// this map as initial map.
ObjectRef GetConstructor() const;
base::Optional<MapRef> AsElementsKind(ElementsKind kind) const;
class FixedArrayBaseRef : public HeapObjectRef {
using HeapObjectRef::HeapObjectRef;
Handle<FixedArrayBase> object() const;
int length() const;
class FixedArrayRef : public FixedArrayBaseRef {
using FixedArrayBaseRef::FixedArrayBaseRef;
Handle<FixedArray> object() const;
ObjectRef get(int i) const;
class FixedDoubleArrayRef : public FixedArrayBaseRef {
using FixedArrayBaseRef::FixedArrayBaseRef;
Handle<FixedDoubleArray> object() const;
double get_scalar(int i) const;
bool is_the_hole(int i) const;
class BytecodeArrayRef : public FixedArrayBaseRef {
using FixedArrayBaseRef::FixedArrayBaseRef;
Handle<BytecodeArray> object() const;
int register_count() const;
int parameter_count() const;
interpreter::Register incoming_new_target_or_generator_register() const;
class JSArrayRef : public JSObjectRef {
using JSObjectRef::JSObjectRef;
Handle<JSArray> object() const;
ObjectRef length() const;
// Return the element at key {index} if the array has a copy-on-write elements
// storage and {index} is known to be an own data property.
base::Optional<ObjectRef> GetOwnCowElement(uint32_t index,
bool serialize = false) const;
class ScopeInfoRef : public HeapObjectRef {
using HeapObjectRef::HeapObjectRef;
Handle<ScopeInfo> object() const;
int ContextLength() const;
V(int, internal_formal_parameter_count) \
V(bool, has_duplicate_parameters) \
V(int, function_map_index) \
V(FunctionKind, kind) \
V(LanguageMode, language_mode) \
V(bool, native) \
V(bool, HasBreakInfo) \
V(bool, HasBuiltinId) \
V(bool, construct_as_builtin) \
V(bool, HasBytecodeArray) \
V(bool, is_safe_to_skip_arguments_adaptor) \
V(bool, IsInlineable) \
V(bool, is_compiled)
class V8_EXPORT_PRIVATE SharedFunctionInfoRef : public HeapObjectRef {
using HeapObjectRef::HeapObjectRef;
Handle<SharedFunctionInfo> object() const;
int builtin_id() const;
BytecodeArrayRef GetBytecodeArray() const;
#define DECL_ACCESSOR(type, name) type name() const;
bool IsSerializedForCompilation(FeedbackVectorRef feedback) const;
void SetSerializedForCompilation(FeedbackVectorRef feedback);
class StringRef : public NameRef {
using NameRef::NameRef;
Handle<String> object() const;
int length() const;
uint16_t GetFirstChar();
base::Optional<double> ToNumber();
bool IsSeqString() const;
bool IsExternalString() const;
class SymbolRef : public NameRef {
using NameRef::NameRef;
Handle<Symbol> object() const;
class JSTypedArrayRef : public JSObjectRef {
using JSObjectRef::JSObjectRef;
Handle<JSTypedArray> object() const;
bool is_on_heap() const;
size_t length() const;
void* elements_external_pointer() const;
void Serialize();
bool serialized() const;
HeapObjectRef buffer() const;
class ModuleRef : public HeapObjectRef {
using HeapObjectRef::HeapObjectRef;
Handle<Module> object() const;
void Serialize();
CellRef GetCell(int cell_index) const;
class CellRef : public HeapObjectRef {
using HeapObjectRef::HeapObjectRef;
Handle<Cell> object() const;
ObjectRef value() const;
class JSGlobalProxyRef : public JSObjectRef {
using JSObjectRef::JSObjectRef;
Handle<JSGlobalProxy> object() const;
// If {serialize} is false:
// If the property is known to exist as a property cell (on the global
// object), return that property cell. Otherwise (not known to exist as a
// property cell or known not to exist as a property cell) return nothing.
// If {serialize} is true:
// Like above but potentially access the heap and serialize the necessary
// information.
base::Optional<PropertyCellRef> GetPropertyCell(NameRef const& name,
bool serialize = false) const;
class CodeRef : public HeapObjectRef {
using HeapObjectRef::HeapObjectRef;
Handle<Code> object() const;
class InternalizedStringRef : public StringRef {
using StringRef::StringRef;
Handle<InternalizedString> object() const;
class ProcessedFeedback : public ZoneObject {
enum Kind { kInsufficient, kGlobalAccess, kNamedAccess, kElementAccess };
Kind kind() const { return kind_; }
explicit ProcessedFeedback(Kind kind) : kind_(kind) {}
Kind const kind_;
class InsufficientFeedback final : public ProcessedFeedback {
class GlobalAccessFeedback : public ProcessedFeedback {
explicit GlobalAccessFeedback(PropertyCellRef cell);
GlobalAccessFeedback(ContextRef script_context, int slot_index,
bool immutable);
bool IsPropertyCell() const;
PropertyCellRef property_cell() const;
bool IsScriptContextSlot() const { return !IsPropertyCell(); }
ContextRef script_context() const;
int slot_index() const;
bool immutable() const;
base::Optional<ObjectRef> GetConstantHint() const;
ObjectRef const cell_or_context_;
int const index_and_immutable_;
class ElementAccessFeedback : public ProcessedFeedback {
explicit ElementAccessFeedback(Zone* zone);
// No transition sources appear in {receiver_maps}.
// All transition targets appear in {receiver_maps}.
ZoneVector<Handle<Map>> receiver_maps;
ZoneVector<std::pair<Handle<Map>, Handle<Map>>> transitions;
class MapIterator {
bool done() const;
void advance();
MapRef current() const;
friend class ElementAccessFeedback;
explicit MapIterator(ElementAccessFeedback const& processed,
JSHeapBroker* broker);
ElementAccessFeedback const& processed_;
JSHeapBroker* const broker_;
size_t index_ = 0;
// Iterator over all maps: first {receiver_maps}, then transition sources.
MapIterator all_maps(JSHeapBroker* broker) const;
class NamedAccessFeedback : public ProcessedFeedback {
NamedAccessFeedback(NameRef const& name,
ZoneVector<PropertyAccessInfo> const& access_infos);
NameRef const& name() const { return name_; }
ZoneVector<PropertyAccessInfo> const& access_infos() const {
return access_infos_;
NameRef const name_;
ZoneVector<PropertyAccessInfo> const access_infos_;
struct FeedbackSource {
FeedbackSource(Handle<FeedbackVector> vector_, FeedbackSlot slot_)
: vector(vector_), slot(slot_) {}
explicit FeedbackSource(FeedbackNexus const& nexus);
explicit FeedbackSource(VectorSlotPair const& pair);
Handle<FeedbackVector> const vector;
FeedbackSlot const slot;
struct Hash {
size_t operator()(FeedbackSource const& source) const {
return base::hash_combine(source.vector.address(), source.slot);
struct Equal {
bool operator()(FeedbackSource const& lhs,
FeedbackSource const& rhs) const {
return lhs.vector.equals(rhs.vector) && lhs.slot == rhs.slot;
class V8_EXPORT_PRIVATE JSHeapBroker {
JSHeapBroker(Isolate* isolate, Zone* broker_zone);
void SetNativeContextRef();
void SerializeStandardObjects();
Isolate* isolate() const { return isolate_; }
Zone* zone() const { return current_zone_; }
NativeContextRef native_context() const { return native_context_.value(); }
PerIsolateCompilerCache* compiler_cache() const { return compiler_cache_; }
enum BrokerMode { kDisabled, kSerializing, kSerialized, kRetired };
BrokerMode mode() const { return mode_; }
void StartSerializing();
void StopSerializing();
void Retire();
bool SerializingAllowed() const;
// Returns nullptr iff handle unknown.
ObjectData* GetData(Handle<Object>) const;
// Never returns nullptr.
ObjectData* GetOrCreateData(Handle<Object>);
// Like the previous but wraps argument in handle first (for convenience).
ObjectData* GetOrCreateData(Object);
// Check if {object} is any native context's %ArrayPrototype% or
// %ObjectPrototype%.
bool IsArrayOrObjectPrototype(const JSObjectRef& object) const;
bool HasFeedback(FeedbackSource const& source) const;
// The processed {feedback} can be {nullptr}, indicating that the original
// feedback didn't contain information relevant for Turbofan.
void SetFeedback(FeedbackSource const& source,
ProcessedFeedback const* feedback);
ProcessedFeedback const* GetFeedback(FeedbackSource const& source) const;
// Convenience wrappers around GetFeedback.
ElementAccessFeedback const* GetElementAccessFeedback(
FeedbackSource const& source) const;
GlobalAccessFeedback const* GetGlobalAccessFeedback(
FeedbackSource const& source) const;
// TODO(neis): Move these into serializer when we're always in the background.
ElementAccessFeedback const* ProcessFeedbackMapsForElementAccess(
MapHandles const& maps);
GlobalAccessFeedback const* ProcessFeedbackForGlobalAccess(
FeedbackSource const& source);
std::ostream& Trace();
void IncrementTracingIndentation();
void DecrementTracingIndentation();
friend class HeapObjectRef;
friend class ObjectRef;
friend class ObjectData;
void SerializeShareableObjects();
void CollectArrayAndObjectPrototypes();
Isolate* const isolate_;
Zone* const broker_zone_;
Zone* current_zone_;
base::Optional<NativeContextRef> native_context_;
RefsMap* refs_;
ZoneUnorderedSet<Handle<JSObject>, Handle<JSObject>::hash,
BrokerMode mode_ = kDisabled;
StdoutStream trace_out_;
unsigned trace_indentation_ = 0;
PerIsolateCompilerCache* compiler_cache_;
ZoneUnorderedMap<FeedbackSource, ProcessedFeedback const*,
FeedbackSource::Hash, FeedbackSource::Equal>
static const size_t kMinimalRefsBucketCount = 8; // must be power of 2
static const size_t kInitialRefsBucketCount = 1024; // must be power of 2
optionally_something) \
auto optionally_something_ = optionally_something; \
if (!optionally_something_) \
return NoChangeBecauseOfMissingData(broker(), __FUNCTION__, __LINE__); \
something_var = *optionally_something_;
class Reduction;
Reduction NoChangeBecauseOfMissingData(JSHeapBroker* broker,
const char* function, int line);
// Miscellaneous definitions that should be moved elsewhere once concurrent
// compilation is finished.
bool CanInlineElementAccess(MapRef const& map);
#define TRACE_BROKER(broker, x) \
do { \
if (FLAG_trace_heap_broker_verbose) broker->Trace() << x << '\n'; \
} while (false)
#define TRACE_BROKER_MISSING(broker, x) \
do { \
if (FLAG_trace_heap_broker) \
broker->Trace() << __FUNCTION__ << ": missing " << x << '\n'; \
} while (false)
} // namespace compiler
} // namespace internal
} // namespace v8