// Copyright 2012 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/code-stubs.h" #include #include "src/arguments.h" #include "src/assembler-inl.h" #include "src/ast/ast.h" #include "src/bootstrapper.h" #include "src/code-factory.h" #include "src/code-stub-assembler.h" #include "src/code-stubs-utils.h" #include "src/counters.h" #include "src/factory.h" #include "src/gdb-jit.h" #include "src/heap/heap-inl.h" #include "src/ic/ic-stats.h" #include "src/ic/ic.h" #include "src/macro-assembler.h" #include "src/objects-inl.h" #include "src/tracing/tracing-category-observer.h" namespace v8 { namespace internal { using compiler::CodeAssemblerState; CodeStubDescriptor::CodeStubDescriptor(CodeStub* stub) : isolate_(stub->isolate()), call_descriptor_(stub->GetCallInterfaceDescriptor()), stack_parameter_count_(no_reg), hint_stack_parameter_count_(-1), function_mode_(NOT_JS_FUNCTION_STUB_MODE), deoptimization_handler_(NULL), miss_handler_(), has_miss_handler_(false) { stub->InitializeDescriptor(this); } CodeStubDescriptor::CodeStubDescriptor(Isolate* isolate, uint32_t stub_key) : isolate_(isolate), stack_parameter_count_(no_reg), hint_stack_parameter_count_(-1), function_mode_(NOT_JS_FUNCTION_STUB_MODE), deoptimization_handler_(NULL), miss_handler_(), has_miss_handler_(false) { CodeStub::InitializeDescriptor(isolate, stub_key, this); } void CodeStubDescriptor::Initialize(Address deoptimization_handler, int hint_stack_parameter_count, StubFunctionMode function_mode) { deoptimization_handler_ = deoptimization_handler; hint_stack_parameter_count_ = hint_stack_parameter_count; function_mode_ = function_mode; } void CodeStubDescriptor::Initialize(Register stack_parameter_count, Address deoptimization_handler, int hint_stack_parameter_count, StubFunctionMode function_mode) { Initialize(deoptimization_handler, hint_stack_parameter_count, function_mode); stack_parameter_count_ = stack_parameter_count; } bool CodeStub::FindCodeInCache(Code** code_out) { UnseededNumberDictionary* stubs = isolate()->heap()->code_stubs(); int index = stubs->FindEntry(isolate(), GetKey()); if (index != UnseededNumberDictionary::kNotFound) { *code_out = Code::cast(stubs->ValueAt(index)); return true; } return false; } void CodeStub::RecordCodeGeneration(Handle code) { std::ostringstream os; os << *this; PROFILE(isolate(), CodeCreateEvent(CodeEventListener::STUB_TAG, AbstractCode::cast(*code), os.str().c_str())); Counters* counters = isolate()->counters(); counters->total_stubs_code_size()->Increment(code->instruction_size()); #ifdef DEBUG code->VerifyEmbeddedObjects(); #endif } void CodeStub::DeleteStubFromCacheForTesting() { Heap* heap = isolate_->heap(); Handle dict(heap->code_stubs()); int entry = dict->FindEntry(GetKey()); DCHECK_NE(UnseededNumberDictionary::kNotFound, entry); dict = UnseededNumberDictionary::DeleteEntry(dict, entry); heap->SetRootCodeStubs(*dict); } Handle PlatformCodeStub::GenerateCode() { Factory* factory = isolate()->factory(); // Generate the new code. MacroAssembler masm(isolate(), NULL, 256, CodeObjectRequired::kYes); { // Update the static counter each time a new code stub is generated. isolate()->counters()->code_stubs()->Increment(); // Generate the code for the stub. // TODO(yangguo): remove this once we can serialize IC stubs. masm.enable_serializer(); NoCurrentFrameScope scope(&masm); Generate(&masm); } // Create the code object. CodeDesc desc; masm.GetCode(isolate(), &desc); // Copy the generated code into a heap object. Handle new_object = factory->NewCode( desc, Code::STUB, masm.CodeObject(), NeedsImmovableCode()); return new_object; } Handle CodeStub::GetCode() { Heap* heap = isolate()->heap(); Code* code; if (FindCodeInCache(&code)) { DCHECK(code->is_stub()); return handle(code); } { HandleScope scope(isolate()); // Canonicalize handles, so that we can share constant pool entries pointing // to code targets without dereferencing their handles. CanonicalHandleScope canonical(isolate()); Handle new_object = GenerateCode(); new_object->set_stub_key(GetKey()); FinishCode(new_object); RecordCodeGeneration(new_object); #ifdef ENABLE_DISASSEMBLER if (FLAG_print_code_stubs) { CodeTracer::Scope trace_scope(isolate()->GetCodeTracer()); OFStream os(trace_scope.file()); std::ostringstream name; name << *this; new_object->Disassemble(name.str().c_str(), os); os << "\n"; } #endif // Update the dictionary and the root in Heap. Handle dict = UnseededNumberDictionary::Set( handle(heap->code_stubs()), GetKey(), new_object); heap->SetRootCodeStubs(*dict); code = *new_object; } Activate(code); DCHECK(!NeedsImmovableCode() || Heap::IsImmovable(code) || heap->code_space()->FirstPage()->Contains(code->address())); return Handle(code, isolate()); } CodeStub::Major CodeStub::GetMajorKey(Code* code_stub) { return MajorKeyFromKey(code_stub->stub_key()); } const char* CodeStub::MajorName(CodeStub::Major major_key) { switch (major_key) { #define DEF_CASE(name) case name: return #name "Stub"; CODE_STUB_LIST(DEF_CASE) #undef DEF_CASE case NoCache: return "Stub"; case NUMBER_OF_IDS: UNREACHABLE(); } return NULL; } void CodeStub::PrintBaseName(std::ostream& os) const { // NOLINT os << MajorName(MajorKey()); } void CodeStub::PrintName(std::ostream& os) const { // NOLINT PrintBaseName(os); PrintState(os); } void CodeStub::Dispatch(Isolate* isolate, uint32_t key, void** value_out, DispatchedCall call) { switch (MajorKeyFromKey(key)) { #define DEF_CASE(NAME) \ case NAME: { \ NAME##Stub stub(key, isolate); \ CodeStub* pstub = &stub; \ call(pstub, value_out); \ break; \ } CODE_STUB_LIST(DEF_CASE) #undef DEF_CASE case NUMBER_OF_IDS: case NoCache: UNREACHABLE(); break; } } static void InitializeDescriptorDispatchedCall(CodeStub* stub, void** value_out) { CodeStubDescriptor* descriptor_out = reinterpret_cast(value_out); stub->InitializeDescriptor(descriptor_out); descriptor_out->set_call_descriptor(stub->GetCallInterfaceDescriptor()); } void CodeStub::InitializeDescriptor(Isolate* isolate, uint32_t key, CodeStubDescriptor* desc) { void** value_out = reinterpret_cast(desc); Dispatch(isolate, key, value_out, &InitializeDescriptorDispatchedCall); } void CodeStub::GetCodeDispatchCall(CodeStub* stub, void** value_out) { Handle* code_out = reinterpret_cast*>(value_out); *code_out = stub->GetCode(); } MaybeHandle CodeStub::GetCode(Isolate* isolate, uint32_t key) { HandleScope scope(isolate); Handle code; void** value_out = reinterpret_cast(&code); Dispatch(isolate, key, value_out, &GetCodeDispatchCall); return scope.CloseAndEscape(code); } void StringAddStub::PrintBaseName(std::ostream& os) const { // NOLINT os << "StringAddStub_" << flags() << "_" << pretenure_flag(); } TF_STUB(StringAddStub, CodeStubAssembler) { StringAddFlags flags = stub->flags(); PretenureFlag pretenure_flag = stub->pretenure_flag(); Node* left = Parameter(Descriptor::kLeft); Node* right = Parameter(Descriptor::kRight); Node* context = Parameter(Descriptor::kContext); if ((flags & STRING_ADD_CHECK_LEFT) != 0) { DCHECK((flags & STRING_ADD_CONVERT) != 0); // TODO(danno): The ToString and JSReceiverToPrimitive below could be // combined to avoid duplicate smi and instance type checks. left = ToString(context, JSReceiverToPrimitive(context, left)); } if ((flags & STRING_ADD_CHECK_RIGHT) != 0) { DCHECK((flags & STRING_ADD_CONVERT) != 0); // TODO(danno): The ToString and JSReceiverToPrimitive below could be // combined to avoid duplicate smi and instance type checks. right = ToString(context, JSReceiverToPrimitive(context, right)); } if ((flags & STRING_ADD_CHECK_BOTH) == 0) { CodeStubAssembler::AllocationFlag allocation_flags = (pretenure_flag == TENURED) ? CodeStubAssembler::kPretenured : CodeStubAssembler::kNone; Return(StringAdd(context, left, right, allocation_flags)); } else { Callable callable = CodeFactory::StringAdd(isolate(), STRING_ADD_CHECK_NONE, pretenure_flag); TailCallStub(callable, context, left, right); } } Handle TurboFanCodeStub::GenerateCode() { const char* name = CodeStub::MajorName(MajorKey()); Zone zone(isolate()->allocator(), ZONE_NAME); CallInterfaceDescriptor descriptor(GetCallInterfaceDescriptor()); compiler::CodeAssemblerState state(isolate(), &zone, descriptor, Code::STUB, name); GenerateAssembly(&state); return compiler::CodeAssembler::GenerateCode(&state); } TF_STUB(ElementsTransitionAndStoreStub, CodeStubAssembler) { Node* receiver = Parameter(Descriptor::kReceiver); Node* key = Parameter(Descriptor::kName); Node* value = Parameter(Descriptor::kValue); Node* map = Parameter(Descriptor::kMap); Node* slot = Parameter(Descriptor::kSlot); Node* vector = Parameter(Descriptor::kVector); Node* context = Parameter(Descriptor::kContext); Comment( "ElementsTransitionAndStoreStub: from_kind=%s, to_kind=%s," " is_jsarray=%d, store_mode=%d", ElementsKindToString(stub->from_kind()), ElementsKindToString(stub->to_kind()), stub->is_jsarray(), stub->store_mode()); Label miss(this); if (FLAG_trace_elements_transitions) { // Tracing elements transitions is the job of the runtime. Goto(&miss); } else { TransitionElementsKind(receiver, map, stub->from_kind(), stub->to_kind(), stub->is_jsarray(), &miss); EmitElementStore(receiver, key, value, stub->is_jsarray(), stub->to_kind(), stub->store_mode(), &miss); Return(value); } BIND(&miss); { Comment("Miss"); TailCallRuntime(Runtime::kElementsTransitionAndStoreIC_Miss, context, receiver, key, value, map, slot, vector); } } TF_STUB(TransitionElementsKindStub, CodeStubAssembler) { Node* context = Parameter(Descriptor::kContext); Node* object = Parameter(Descriptor::kObject); Node* new_map = Parameter(Descriptor::kMap); Label bailout(this); TransitionElementsKind(object, new_map, stub->from_kind(), stub->to_kind(), stub->is_jsarray(), &bailout); Return(object); BIND(&bailout); { Comment("Call runtime"); TailCallRuntime(Runtime::kTransitionElementsKind, context, object, new_map); } } // TODO(ishell): move to builtins. TF_STUB(NumberToStringStub, CodeStubAssembler) { Node* context = Parameter(Descriptor::kContext); Node* argument = Parameter(Descriptor::kArgument); Return(NumberToString(context, argument)); } // TODO(ishell): move to builtins. TF_STUB(SubStringStub, CodeStubAssembler) { Node* context = Parameter(Descriptor::kContext); Node* string = Parameter(Descriptor::kString); Node* from = Parameter(Descriptor::kFrom); Node* to = Parameter(Descriptor::kTo); Return(SubString(context, string, from, to)); } // TODO(ishell): move to builtins-handler-gen. TF_STUB(KeyedLoadSloppyArgumentsStub, CodeStubAssembler) { Node* receiver = Parameter(Descriptor::kReceiver); Node* key = Parameter(Descriptor::kName); Node* slot = Parameter(Descriptor::kSlot); Node* vector = Parameter(Descriptor::kVector); Node* context = Parameter(Descriptor::kContext); Label miss(this); Node* result = LoadKeyedSloppyArguments(receiver, key, &miss); Return(result); BIND(&miss); { Comment("Miss"); TailCallRuntime(Runtime::kKeyedLoadIC_Miss, context, receiver, key, slot, vector); } } // TODO(ishell): move to builtins-handler-gen. TF_STUB(KeyedStoreSloppyArgumentsStub, CodeStubAssembler) { Node* receiver = Parameter(Descriptor::kReceiver); Node* key = Parameter(Descriptor::kName); Node* value = Parameter(Descriptor::kValue); Node* slot = Parameter(Descriptor::kSlot); Node* vector = Parameter(Descriptor::kVector); Node* context = Parameter(Descriptor::kContext); Label miss(this); StoreKeyedSloppyArguments(receiver, key, value, &miss); Return(value); BIND(&miss); { Comment("Miss"); TailCallRuntime(Runtime::kKeyedStoreIC_Miss, context, value, slot, vector, receiver, key); } } TF_STUB(LoadScriptContextFieldStub, CodeStubAssembler) { Comment("LoadScriptContextFieldStub: context_index=%d, slot=%d", stub->context_index(), stub->slot_index()); Node* context = Parameter(Descriptor::kContext); Node* script_context = LoadScriptContext(context, stub->context_index()); Node* result = LoadFixedArrayElement(script_context, stub->slot_index()); Return(result); } TF_STUB(StoreScriptContextFieldStub, CodeStubAssembler) { Comment("StoreScriptContextFieldStub: context_index=%d, slot=%d", stub->context_index(), stub->slot_index()); Node* value = Parameter(Descriptor::kValue); Node* context = Parameter(Descriptor::kContext); Node* script_context = LoadScriptContext(context, stub->context_index()); StoreFixedArrayElement(script_context, IntPtrConstant(stub->slot_index()), value); Return(value); } // TODO(ishell): move to builtins-handler-gen. TF_STUB(StoreInterceptorStub, CodeStubAssembler) { Node* receiver = Parameter(Descriptor::kReceiver); Node* name = Parameter(Descriptor::kName); Node* value = Parameter(Descriptor::kValue); Node* slot = Parameter(Descriptor::kSlot); Node* vector = Parameter(Descriptor::kVector); Node* context = Parameter(Descriptor::kContext); TailCallRuntime(Runtime::kStorePropertyWithInterceptor, context, value, slot, vector, receiver, name); } // TODO(ishell): move to builtins-handler-gen. TF_STUB(LoadIndexedInterceptorStub, CodeStubAssembler) { Node* receiver = Parameter(Descriptor::kReceiver); Node* key = Parameter(Descriptor::kName); Node* slot = Parameter(Descriptor::kSlot); Node* vector = Parameter(Descriptor::kVector); Node* context = Parameter(Descriptor::kContext); Label if_keyispositivesmi(this), if_keyisinvalid(this); Branch(TaggedIsPositiveSmi(key), &if_keyispositivesmi, &if_keyisinvalid); BIND(&if_keyispositivesmi); TailCallRuntime(Runtime::kLoadElementWithInterceptor, context, receiver, key); BIND(&if_keyisinvalid); TailCallRuntime(Runtime::kKeyedLoadIC_Miss, context, receiver, key, slot, vector); } void JSEntryStub::FinishCode(Handle code) { Handle handler_table = code->GetIsolate()->factory()->NewFixedArray(1, TENURED); handler_table->set(0, Smi::FromInt(handler_offset_)); code->set_handler_table(*handler_table); } // TODO(ishell): move to builtins. TF_STUB(GetPropertyStub, CodeStubAssembler) { Label call_runtime(this, Label::kDeferred), return_undefined(this), end(this); Node* object = Parameter(Descriptor::kObject); Node* key = Parameter(Descriptor::kKey); Node* context = Parameter(Descriptor::kContext); VARIABLE(var_result, MachineRepresentation::kTagged); CodeStubAssembler::LookupInHolder lookup_property_in_holder = [=, &var_result, &end](Node* receiver, Node* holder, Node* holder_map, Node* holder_instance_type, Node* unique_name, Label* next_holder, Label* if_bailout) { VARIABLE(var_value, MachineRepresentation::kTagged); Label if_found(this); TryGetOwnProperty(context, receiver, holder, holder_map, holder_instance_type, unique_name, &if_found, &var_value, next_holder, if_bailout); BIND(&if_found); { var_result.Bind(var_value.value()); Goto(&end); } }; CodeStubAssembler::LookupInHolder lookup_element_in_holder = [=](Node* receiver, Node* holder, Node* holder_map, Node* holder_instance_type, Node* index, Label* next_holder, Label* if_bailout) { // Not supported yet. Use(next_holder); Goto(if_bailout); }; TryPrototypeChainLookup(object, key, lookup_property_in_holder, lookup_element_in_holder, &return_undefined, &call_runtime); BIND(&return_undefined); { var_result.Bind(UndefinedConstant()); Goto(&end); } BIND(&call_runtime); { var_result.Bind(CallRuntime(Runtime::kGetProperty, context, object, key)); Goto(&end); } BIND(&end); Return(var_result.value()); } // TODO(ishell): move to builtins-handler-gen. TF_STUB(StoreSlowElementStub, CodeStubAssembler) { Node* receiver = Parameter(Descriptor::kReceiver); Node* name = Parameter(Descriptor::kName); Node* value = Parameter(Descriptor::kValue); Node* slot = Parameter(Descriptor::kSlot); Node* vector = Parameter(Descriptor::kVector); Node* context = Parameter(Descriptor::kContext); TailCallRuntime(Runtime::kKeyedStoreIC_Slow, context, value, slot, vector, receiver, name); } TF_STUB(StoreFastElementStub, CodeStubAssembler) { Comment("StoreFastElementStub: js_array=%d, elements_kind=%s, store_mode=%d", stub->is_js_array(), ElementsKindToString(stub->elements_kind()), stub->store_mode()); Node* receiver = Parameter(Descriptor::kReceiver); Node* key = Parameter(Descriptor::kName); Node* value = Parameter(Descriptor::kValue); Node* slot = Parameter(Descriptor::kSlot); Node* vector = Parameter(Descriptor::kVector); Node* context = Parameter(Descriptor::kContext); Label miss(this); EmitElementStore(receiver, key, value, stub->is_js_array(), stub->elements_kind(), stub->store_mode(), &miss); Return(value); BIND(&miss); { Comment("Miss"); TailCallRuntime(Runtime::kKeyedStoreIC_Miss, context, value, slot, vector, receiver, key); } } // static void StoreFastElementStub::GenerateAheadOfTime(Isolate* isolate) { if (FLAG_minimal) return; StoreFastElementStub(isolate, false, HOLEY_ELEMENTS, STANDARD_STORE) .GetCode(); StoreFastElementStub(isolate, false, HOLEY_ELEMENTS, STORE_AND_GROW_NO_TRANSITION) .GetCode(); for (int i = FIRST_FAST_ELEMENTS_KIND; i <= LAST_FAST_ELEMENTS_KIND; i++) { ElementsKind kind = static_cast(i); StoreFastElementStub(isolate, true, kind, STANDARD_STORE).GetCode(); StoreFastElementStub(isolate, true, kind, STORE_AND_GROW_NO_TRANSITION) .GetCode(); } } void ProfileEntryHookStub::EntryHookTrampoline(intptr_t function, intptr_t stack_pointer, Isolate* isolate) { FunctionEntryHook entry_hook = isolate->function_entry_hook(); DCHECK(entry_hook != NULL); entry_hook(function, stack_pointer); } TF_STUB(ArrayNoArgumentConstructorStub, CodeStubAssembler) { ElementsKind elements_kind = stub->elements_kind(); Node* native_context = LoadObjectField(Parameter(Descriptor::kFunction), JSFunction::kContextOffset); bool track_allocation_site = AllocationSite::ShouldTrack(elements_kind) && stub->override_mode() != DISABLE_ALLOCATION_SITES; Node* allocation_site = track_allocation_site ? Parameter(Descriptor::kAllocationSite) : nullptr; Node* array_map = LoadJSArrayElementsMap(elements_kind, native_context); Node* array = AllocateJSArray(elements_kind, array_map, IntPtrConstant(JSArray::kPreallocatedArrayElements), SmiConstant(0), allocation_site); Return(array); } TF_STUB(InternalArrayNoArgumentConstructorStub, CodeStubAssembler) { Node* array_map = LoadObjectField(Parameter(Descriptor::kFunction), JSFunction::kPrototypeOrInitialMapOffset); Node* array = AllocateJSArray( stub->elements_kind(), array_map, IntPtrConstant(JSArray::kPreallocatedArrayElements), SmiConstant(0)); Return(array); } class ArrayConstructorAssembler : public CodeStubAssembler { public: typedef compiler::Node Node; explicit ArrayConstructorAssembler(compiler::CodeAssemblerState* state) : CodeStubAssembler(state) {} void GenerateConstructor(Node* context, Node* array_function, Node* array_map, Node* array_size, Node* allocation_site, ElementsKind elements_kind, AllocationSiteMode mode); }; void ArrayConstructorAssembler::GenerateConstructor( Node* context, Node* array_function, Node* array_map, Node* array_size, Node* allocation_site, ElementsKind elements_kind, AllocationSiteMode mode) { Label ok(this); Label smi_size(this); Label small_smi_size(this); Label call_runtime(this, Label::kDeferred); Branch(TaggedIsSmi(array_size), &smi_size, &call_runtime); BIND(&smi_size); if (IsFastPackedElementsKind(elements_kind)) { Label abort(this, Label::kDeferred); Branch(SmiEqual(array_size, SmiConstant(0)), &small_smi_size, &abort); BIND(&abort); Node* reason = SmiConstant(kAllocatingNonEmptyPackedArray); TailCallRuntime(Runtime::kAbort, context, reason); } else { int element_size = IsDoubleElementsKind(elements_kind) ? kDoubleSize : kPointerSize; int max_fast_elements = (kMaxRegularHeapObjectSize - FixedArray::kHeaderSize - JSArray::kSize - AllocationMemento::kSize) / element_size; Branch(SmiAboveOrEqual(array_size, SmiConstant(max_fast_elements)), &call_runtime, &small_smi_size); } BIND(&small_smi_size); { Node* array = AllocateJSArray( elements_kind, array_map, array_size, array_size, mode == DONT_TRACK_ALLOCATION_SITE ? nullptr : allocation_site, CodeStubAssembler::SMI_PARAMETERS); Return(array); } BIND(&call_runtime); { TailCallRuntime(Runtime::kNewArray, context, array_function, array_size, array_function, allocation_site); } } TF_STUB(ArraySingleArgumentConstructorStub, ArrayConstructorAssembler) { ElementsKind elements_kind = stub->elements_kind(); Node* context = Parameter(Descriptor::kContext); Node* function = Parameter(Descriptor::kFunction); Node* native_context = LoadObjectField(function, JSFunction::kContextOffset); Node* array_map = LoadJSArrayElementsMap(elements_kind, native_context); AllocationSiteMode mode = DONT_TRACK_ALLOCATION_SITE; if (stub->override_mode() == DONT_OVERRIDE) { mode = AllocationSite::ShouldTrack(elements_kind) ? TRACK_ALLOCATION_SITE : DONT_TRACK_ALLOCATION_SITE; } Node* array_size = Parameter(Descriptor::kArraySizeSmiParameter); Node* allocation_site = Parameter(Descriptor::kAllocationSite); GenerateConstructor(context, function, array_map, array_size, allocation_site, elements_kind, mode); } TF_STUB(InternalArraySingleArgumentConstructorStub, ArrayConstructorAssembler) { Node* context = Parameter(Descriptor::kContext); Node* function = Parameter(Descriptor::kFunction); Node* array_map = LoadObjectField(function, JSFunction::kPrototypeOrInitialMapOffset); Node* array_size = Parameter(Descriptor::kArraySizeSmiParameter); Node* allocation_site = UndefinedConstant(); GenerateConstructor(context, function, array_map, array_size, allocation_site, stub->elements_kind(), DONT_TRACK_ALLOCATION_SITE); } TF_STUB(GrowArrayElementsStub, CodeStubAssembler) { Label runtime(this, CodeStubAssembler::Label::kDeferred); Node* object = Parameter(Descriptor::kObject); Node* key = Parameter(Descriptor::kKey); Node* context = Parameter(Descriptor::kContext); ElementsKind kind = stub->elements_kind(); Node* elements = LoadElements(object); Node* new_elements = TryGrowElementsCapacity(object, elements, kind, key, &runtime); Return(new_elements); BIND(&runtime); // TODO(danno): Make this a tail call when the stub is only used from TurboFan // code. This musn't be a tail call for now, since the caller site in lithium // creates a safepoint. This safepoint musn't have a different number of // arguments on the stack in the case that a GC happens from the slow-case // allocation path (zero, since all the stubs inputs are in registers) and // when the call happens (it would be two in the tail call case due to the // tail call pushing the arguments on the stack for the runtime call). By not // tail-calling, the runtime call case also has zero arguments on the stack // for the stub frame. Return(CallRuntime(Runtime::kGrowArrayElements, context, object, key)); } ArrayConstructorStub::ArrayConstructorStub(Isolate* isolate) : PlatformCodeStub(isolate) {} InternalArrayConstructorStub::InternalArrayConstructorStub(Isolate* isolate) : PlatformCodeStub(isolate) {} CommonArrayConstructorStub::CommonArrayConstructorStub( Isolate* isolate, ElementsKind kind, AllocationSiteOverrideMode override_mode) : TurboFanCodeStub(isolate) { // It only makes sense to override local allocation site behavior // if there is a difference between the global allocation site policy // for an ElementsKind and the desired usage of the stub. DCHECK(override_mode != DISABLE_ALLOCATION_SITES || AllocationSite::ShouldTrack(kind)); set_sub_minor_key(ElementsKindBits::encode(kind) | AllocationSiteOverrideModeBits::encode(override_mode)); } } // namespace internal } // namespace v8