// Copyright 2020 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_OBJECTS_JS_FUNCTION_INL_H_ #define V8_OBJECTS_JS_FUNCTION_INL_H_ #include "src/objects/js-function.h" // Include other inline headers *after* including js-function.h, such that e.g. // the definition of JSFunction is available (and this comment prevents // clang-format from merging that include into the following ones). #include "src/diagnostics/code-tracer.h" #include "src/ic/ic.h" #include "src/init/bootstrapper.h" #include "src/objects/feedback-cell-inl.h" #include "src/objects/map-updater.h" #include "src/objects/shared-function-info-inl.h" // Has to be the last include (doesn't have include guards): #include "src/objects/object-macros.h" namespace v8 { namespace internal { #include "torque-generated/src/objects/js-function-tq-inl.inc" TQ_OBJECT_CONSTRUCTORS_IMPL(JSFunctionOrBoundFunctionOrWrappedFunction) TQ_OBJECT_CONSTRUCTORS_IMPL(JSBoundFunction) TQ_OBJECT_CONSTRUCTORS_IMPL(JSWrappedFunction) TQ_OBJECT_CONSTRUCTORS_IMPL(JSFunction) ACCESSORS(JSFunction, raw_feedback_cell, FeedbackCell, kFeedbackCellOffset) RELEASE_ACQUIRE_ACCESSORS(JSFunction, raw_feedback_cell, FeedbackCell, kFeedbackCellOffset) DEF_GETTER(JSFunction, feedback_vector, FeedbackVector) { DCHECK(has_feedback_vector(cage_base)); return FeedbackVector::cast(raw_feedback_cell(cage_base).value(cage_base)); } ClosureFeedbackCellArray JSFunction::closure_feedback_cell_array() const { DCHECK(has_closure_feedback_cell_array()); return ClosureFeedbackCellArray::cast(raw_feedback_cell().value()); } void JSFunction::reset_tiering_state() { DCHECK(has_feedback_vector()); feedback_vector().reset_tiering_state(); } bool JSFunction::ChecksTieringState() { return code().checks_tiering_state(); } void JSFunction::CompleteInobjectSlackTrackingIfActive() { if (!has_prototype_slot()) return; if (has_initial_map() && initial_map().IsInobjectSlackTrackingInProgress()) { MapUpdater::CompleteInobjectSlackTracking(GetIsolate(), initial_map()); } } template <typename IsolateT> AbstractCode JSFunction::abstract_code(IsolateT* isolate) { if (ActiveTierIsIgnition()) { return AbstractCode::cast(shared().GetBytecodeArray(isolate)); } else { return ToAbstractCode(code(kAcquireLoad)); } } int JSFunction::length() { return shared().length(); } ACCESSORS_RELAXED(JSFunction, code, CodeT, kCodeOffset) RELEASE_ACQUIRE_ACCESSORS(JSFunction, code, CodeT, kCodeOffset) RELEASE_ACQUIRE_ACCESSORS(JSFunction, context, Context, kContextOffset) #ifdef V8_EXTERNAL_CODE_SPACE void JSFunction::set_code(Code code, ReleaseStoreTag, WriteBarrierMode mode) { set_code(ToCodeT(code), kReleaseStore, mode); } #endif Address JSFunction::code_entry_point() const { if (V8_EXTERNAL_CODE_SPACE_BOOL) { return CodeDataContainer::cast(code()).code_entry_point(); } else { return code().InstructionStart(); } } // TODO(ishell): Why relaxed read but release store? DEF_GETTER(JSFunction, shared, SharedFunctionInfo) { return shared(cage_base, kRelaxedLoad); } DEF_RELAXED_GETTER(JSFunction, shared, SharedFunctionInfo) { return TaggedField<SharedFunctionInfo, kSharedFunctionInfoOffset>::Relaxed_Load(cage_base, *this); } void JSFunction::set_shared(SharedFunctionInfo value, WriteBarrierMode mode) { // Release semantics to support acquire read in NeedsResetDueToFlushedBytecode RELEASE_WRITE_FIELD(*this, kSharedFunctionInfoOffset, value); CONDITIONAL_WRITE_BARRIER(*this, kSharedFunctionInfoOffset, value, mode); } TieringState JSFunction::tiering_state() const { if (!has_feedback_vector()) return TieringState::kNone; return feedback_vector().tiering_state(); } void JSFunction::set_tiering_state(TieringState state) { DCHECK(has_feedback_vector()); DCHECK(IsNone(state) || ChecksTieringState()); feedback_vector().set_tiering_state(state); } TieringState JSFunction::osr_tiering_state() { DCHECK(has_feedback_vector()); return feedback_vector().osr_tiering_state(); } void JSFunction::set_osr_tiering_state(TieringState marker) { DCHECK(has_feedback_vector()); feedback_vector().set_osr_tiering_state(marker); } DEF_GETTER(JSFunction, has_feedback_vector, bool) { return shared(cage_base).is_compiled() && raw_feedback_cell(cage_base).value(cage_base).IsFeedbackVector( cage_base); } bool JSFunction::has_closure_feedback_cell_array() const { return shared().is_compiled() && raw_feedback_cell().value().IsClosureFeedbackCellArray(); } Context JSFunction::context() { return TaggedField<Context, kContextOffset>::load(*this); } DEF_RELAXED_GETTER(JSFunction, context, Context) { return TaggedField<Context, kContextOffset>::Relaxed_Load(cage_base, *this); } bool JSFunction::has_context() const { return TaggedField<HeapObject, kContextOffset>::load(*this).IsContext(); } JSGlobalProxy JSFunction::global_proxy() { return context().global_proxy(); } NativeContext JSFunction::native_context() { return context().native_context(); } RELEASE_ACQUIRE_ACCESSORS_CHECKED(JSFunction, prototype_or_initial_map, HeapObject, kPrototypeOrInitialMapOffset, map().has_prototype_slot()) DEF_GETTER(JSFunction, has_prototype_slot, bool) { return map(cage_base).has_prototype_slot(); } DEF_GETTER(JSFunction, initial_map, Map) { return Map::cast(prototype_or_initial_map(cage_base, kAcquireLoad)); } DEF_GETTER(JSFunction, has_initial_map, bool) { DCHECK(has_prototype_slot(cage_base)); return prototype_or_initial_map(cage_base, kAcquireLoad).IsMap(cage_base); } DEF_GETTER(JSFunction, has_instance_prototype, bool) { DCHECK(has_prototype_slot(cage_base)); return has_initial_map(cage_base) || !prototype_or_initial_map(cage_base, kAcquireLoad) .IsTheHole(GetReadOnlyRoots(cage_base)); } DEF_GETTER(JSFunction, has_prototype, bool) { DCHECK(has_prototype_slot(cage_base)); return map(cage_base).has_non_instance_prototype() || has_instance_prototype(cage_base); } DEF_GETTER(JSFunction, has_prototype_property, bool) { return (has_prototype_slot(cage_base) && IsConstructor(cage_base)) || IsGeneratorFunction(shared(cage_base).kind()); } DEF_GETTER(JSFunction, PrototypeRequiresRuntimeLookup, bool) { return !has_prototype_property(cage_base) || map(cage_base).has_non_instance_prototype(); } DEF_GETTER(JSFunction, instance_prototype, HeapObject) { DCHECK(has_instance_prototype(cage_base)); if (has_initial_map(cage_base)) { return initial_map(cage_base).prototype(cage_base); } // When there is no initial map and the prototype is a JSReceiver, the // initial map field is used for the prototype field. return HeapObject::cast(prototype_or_initial_map(cage_base, kAcquireLoad)); } DEF_GETTER(JSFunction, prototype, Object) { DCHECK(has_prototype(cage_base)); // If the function's prototype property has been set to a non-JSReceiver // value, that value is stored in the constructor field of the map. if (map(cage_base).has_non_instance_prototype()) { Object prototype = map(cage_base).GetConstructor(cage_base); // The map must have a prototype in that field, not a back pointer. DCHECK(!prototype.IsMap(cage_base)); DCHECK(!prototype.IsFunctionTemplateInfo(cage_base)); return prototype; } return instance_prototype(cage_base); } bool JSFunction::is_compiled() const { return code(kAcquireLoad).builtin_id() != Builtin::kCompileLazy && shared().is_compiled(); } bool JSFunction::ShouldFlushBaselineCode( base::EnumSet<CodeFlushMode> code_flush_mode) { if (!IsBaselineCodeFlushingEnabled(code_flush_mode)) return false; // Do a raw read for shared and code fields here since this function may be // called on a concurrent thread. JSFunction itself should be fully // initialized here but the SharedFunctionInfo, Code objects may not be // initialized. We read using acquire loads to defend against that. Object maybe_shared = ACQUIRE_READ_FIELD(*this, kSharedFunctionInfoOffset); if (!maybe_shared.IsSharedFunctionInfo()) return false; // See crbug.com/v8/11972 for more details on acquire / release semantics for // code field. We don't use release stores when copying code pointers from // SFI / FV to JSFunction but it is safe in practice. Object maybe_code = ACQUIRE_READ_FIELD(*this, kCodeOffset); if (!maybe_code.IsCodeT()) return false; CodeT code = CodeT::cast(maybe_code); if (code.kind() != CodeKind::BASELINE) return false; SharedFunctionInfo shared = SharedFunctionInfo::cast(maybe_shared); return shared.ShouldFlushCode(code_flush_mode); } bool JSFunction::NeedsResetDueToFlushedBytecode() { // Do a raw read for shared and code fields here since this function may be // called on a concurrent thread. JSFunction itself should be fully // initialized here but the SharedFunctionInfo, Code objects may not be // initialized. We read using acquire loads to defend against that. Object maybe_shared = ACQUIRE_READ_FIELD(*this, kSharedFunctionInfoOffset); if (!maybe_shared.IsSharedFunctionInfo()) return false; Object maybe_code = ACQUIRE_READ_FIELD(*this, kCodeOffset); if (!maybe_code.IsCodeT()) return false; CodeT code = CodeT::cast(maybe_code); SharedFunctionInfo shared = SharedFunctionInfo::cast(maybe_shared); return !shared.is_compiled() && code.builtin_id() != Builtin::kCompileLazy; } bool JSFunction::NeedsResetDueToFlushedBaselineCode() { return code().kind() == CodeKind::BASELINE && !shared().HasBaselineCode(); } void JSFunction::ResetIfCodeFlushed( base::Optional<std::function<void(HeapObject object, ObjectSlot slot, HeapObject target)>> gc_notify_updated_slot) { const bool kBytecodeCanFlush = FLAG_flush_bytecode || FLAG_stress_snapshot; const bool kBaselineCodeCanFlush = FLAG_flush_baseline_code || FLAG_stress_snapshot; if (!kBytecodeCanFlush && !kBaselineCodeCanFlush) return; DCHECK_IMPLIES(NeedsResetDueToFlushedBytecode(), kBytecodeCanFlush); if (kBytecodeCanFlush && NeedsResetDueToFlushedBytecode()) { // Bytecode was flushed and function is now uncompiled, reset JSFunction // by setting code to CompileLazy and clearing the feedback vector. set_code(*BUILTIN_CODE(GetIsolate(), CompileLazy)); raw_feedback_cell().reset_feedback_vector(gc_notify_updated_slot); return; } DCHECK_IMPLIES(NeedsResetDueToFlushedBaselineCode(), kBaselineCodeCanFlush); if (kBaselineCodeCanFlush && NeedsResetDueToFlushedBaselineCode()) { // Flush baseline code from the closure if required set_code(*BUILTIN_CODE(GetIsolate(), InterpreterEntryTrampoline)); } } } // namespace internal } // namespace v8 #include "src/objects/object-macros-undef.h" #endif // V8_OBJECTS_JS_FUNCTION_INL_H_