// Copyright 2012 the V8 project authors. All rights reserved. // Redistribution and use in source and binary forms, with or without // modification, are permitted provided that the following conditions are // met: // // * Redistributions of source code must retain the above copyright // notice, this list of conditions and the following disclaimer. // * Redistributions in binary form must reproduce the above // copyright notice, this list of conditions and the following // disclaimer in the documentation and/or other materials provided // with the distribution. // * Neither the name of Google Inc. nor the names of its // contributors may be used to endorse or promote products derived // from this software without specific prior written permission. // // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. #include "v8.h" #include "accessors.h" #include "api.h" #include "arguments.h" #include "codegen.h" #include "execution.h" #include "ic-inl.h" #include "runtime.h" #include "stub-cache.h" namespace v8 { namespace internal { #ifdef DEBUG char IC::TransitionMarkFromState(IC::State state) { switch (state) { case UNINITIALIZED: return '0'; case PREMONOMORPHIC: return 'P'; case MONOMORPHIC: return '1'; case MONOMORPHIC_PROTOTYPE_FAILURE: return '^'; case MEGAMORPHIC: return IsGeneric() ? 'G' : 'N'; // We never see the debugger states here, because the state is // computed from the original code - not the patched code. Let // these cases fall through to the unreachable code below. case DEBUG_BREAK: break; case DEBUG_PREPARE_STEP_IN: break; } UNREACHABLE(); return 0; } void IC::TraceIC(const char* type, Handle name, State old_state, Code* new_target) { if (FLAG_trace_ic) { State new_state = StateFrom(new_target, HEAP->undefined_value(), HEAP->undefined_value()); PrintF("[%s in ", type); StackFrameIterator it; while (it.frame()->fp() != this->fp()) it.Advance(); StackFrame* raw_frame = it.frame(); if (raw_frame->is_internal()) { Isolate* isolate = new_target->GetIsolate(); Code* apply_builtin = isolate->builtins()->builtin( Builtins::kFunctionApply); if (raw_frame->unchecked_code() == apply_builtin) { PrintF("apply from "); it.Advance(); raw_frame = it.frame(); } } JavaScriptFrame::PrintTop(stdout, false, true); bool new_can_grow = Code::GetKeyedAccessGrowMode(new_target->extra_ic_state()) == ALLOW_JSARRAY_GROWTH; PrintF(" (%c->%c%s)", TransitionMarkFromState(old_state), TransitionMarkFromState(new_state), new_can_grow ? ".GROW" : ""); name->Print(); PrintF("]\n"); } } #define TRACE_GENERIC_IC(type, reason) \ do { \ if (FLAG_trace_ic) { \ PrintF("[%s patching generic stub in ", type); \ JavaScriptFrame::PrintTop(stdout, false, true); \ PrintF(" (%s)]\n", reason); \ } \ } while (false) #else #define TRACE_GENERIC_IC(type, reason) #endif // DEBUG #define TRACE_IC(type, name, old_state, new_target) \ ASSERT((TraceIC(type, name, old_state, new_target), true)) IC::IC(FrameDepth depth, Isolate* isolate) : isolate_(isolate) { ASSERT(isolate == Isolate::Current()); // To improve the performance of the (much used) IC code, we unfold // a few levels of the stack frame iteration code. This yields a // ~35% speedup when running DeltaBlue with the '--nouse-ic' flag. const Address entry = Isolate::c_entry_fp(isolate->thread_local_top()); Address* pc_address = reinterpret_cast(entry + ExitFrameConstants::kCallerPCOffset); Address fp = Memory::Address_at(entry + ExitFrameConstants::kCallerFPOffset); // If there's another JavaScript frame on the stack, we need to look // one frame further down the stack to find the frame pointer and // the return address stack slot. if (depth == EXTRA_CALL_FRAME) { const int kCallerPCOffset = StandardFrameConstants::kCallerPCOffset; pc_address = reinterpret_cast(fp + kCallerPCOffset); fp = Memory::Address_at(fp + StandardFrameConstants::kCallerFPOffset); } #ifdef DEBUG StackFrameIterator it; for (int i = 0; i < depth + 1; i++) it.Advance(); StackFrame* frame = it.frame(); ASSERT(fp == frame->fp() && pc_address == frame->pc_address()); #endif fp_ = fp; pc_address_ = pc_address; } #ifdef ENABLE_DEBUGGER_SUPPORT Address IC::OriginalCodeAddress() const { HandleScope scope; // Compute the JavaScript frame for the frame pointer of this IC // structure. We need this to be able to find the function // corresponding to the frame. StackFrameIterator it; while (it.frame()->fp() != this->fp()) it.Advance(); JavaScriptFrame* frame = JavaScriptFrame::cast(it.frame()); // Find the function on the stack and both the active code for the // function and the original code. JSFunction* function = JSFunction::cast(frame->function()); Handle shared(function->shared()); Code* code = shared->code(); ASSERT(Debug::HasDebugInfo(shared)); Code* original_code = Debug::GetDebugInfo(shared)->original_code(); ASSERT(original_code->IsCode()); // Get the address of the call site in the active code. This is the // place where the call to DebugBreakXXX is and where the IC // normally would be. Address addr = Assembler::target_address_from_return_address(pc()); // Return the address in the original code. This is the place where // the call which has been overwritten by the DebugBreakXXX resides // and the place where the inline cache system should look. intptr_t delta = original_code->instruction_start() - code->instruction_start(); return addr + delta; } #endif static bool HasNormalObjectsInPrototypeChain(Isolate* isolate, LookupResult* lookup, Object* receiver) { Object* end = lookup->IsProperty() ? lookup->holder() : Object::cast(isolate->heap()->null_value()); for (Object* current = receiver; current != end; current = current->GetPrototype()) { if (current->IsJSObject() && !JSObject::cast(current)->HasFastProperties() && !current->IsJSGlobalProxy() && !current->IsJSGlobalObject()) { return true; } } return false; } static bool TryRemoveInvalidPrototypeDependentStub(Code* target, Object* receiver, Object* name) { InlineCacheHolderFlag cache_holder = Code::ExtractCacheHolderFromFlags(target->flags()); if (cache_holder == OWN_MAP && !receiver->IsJSObject()) { // The stub was generated for JSObject but called for non-JSObject. // IC::GetCodeCacheHolder is not applicable. return false; } else if (cache_holder == PROTOTYPE_MAP && receiver->GetPrototype()->IsNull()) { // IC::GetCodeCacheHolder is not applicable. return false; } Map* map = IC::GetCodeCacheHolder(receiver, cache_holder)->map(); // Decide whether the inline cache failed because of changes to the // receiver itself or changes to one of its prototypes. // // If there are changes to the receiver itself, the map of the // receiver will have changed and the current target will not be in // the receiver map's code cache. Therefore, if the current target // is in the receiver map's code cache, the inline cache failed due // to prototype check failure. int index = map->IndexInCodeCache(name, target); if (index >= 0) { map->RemoveFromCodeCache(String::cast(name), target, index); return true; } return false; } IC::State IC::StateFrom(Code* target, Object* receiver, Object* name) { IC::State state = target->ic_state(); if (state != MONOMORPHIC || !name->IsString()) return state; if (receiver->IsUndefined() || receiver->IsNull()) return state; // For keyed load/store/call, the most likely cause of cache failure is // that the key has changed. We do not distinguish between // prototype and non-prototype failures for keyed access. Code::Kind kind = target->kind(); if (kind == Code::KEYED_LOAD_IC || kind == Code::KEYED_STORE_IC || kind == Code::KEYED_CALL_IC) { return MONOMORPHIC; } // Remove the target from the code cache if it became invalid // because of changes in the prototype chain to avoid hitting it // again. // Call stubs handle this later to allow extra IC state // transitions. if (kind != Code::CALL_IC && TryRemoveInvalidPrototypeDependentStub(target, receiver, name)) { return MONOMORPHIC_PROTOTYPE_FAILURE; } // The builtins object is special. It only changes when JavaScript // builtins are loaded lazily. It is important to keep inline // caches for the builtins object monomorphic. Therefore, if we get // an inline cache miss for the builtins object after lazily loading // JavaScript builtins, we return uninitialized as the state to // force the inline cache back to monomorphic state. if (receiver->IsJSBuiltinsObject()) { return UNINITIALIZED; } return MONOMORPHIC; } RelocInfo::Mode IC::ComputeMode() { Address addr = address(); Code* code = Code::cast(isolate()->heap()->FindCodeObject(addr)); for (RelocIterator it(code, RelocInfo::kCodeTargetMask); !it.done(); it.next()) { RelocInfo* info = it.rinfo(); if (info->pc() == addr) return info->rmode(); } UNREACHABLE(); return RelocInfo::NONE; } Failure* IC::TypeError(const char* type, Handle object, Handle key) { HandleScope scope(isolate()); Handle args[2] = { key, object }; Handle error = isolate()->factory()->NewTypeError( type, HandleVector(args, 2)); return isolate()->Throw(*error); } Failure* IC::ReferenceError(const char* type, Handle name) { HandleScope scope(isolate()); Handle error = isolate()->factory()->NewReferenceError( type, HandleVector(&name, 1)); return isolate()->Throw(*error); } static int ComputeTypeInfoCountDelta(IC::State old_state, IC::State new_state) { bool was_uninitialized = old_state == UNINITIALIZED || old_state == PREMONOMORPHIC; bool is_uninitialized = new_state == UNINITIALIZED || new_state == PREMONOMORPHIC; return (was_uninitialized && !is_uninitialized) ? 1 : (!was_uninitialized && is_uninitialized) ? -1 : 0; } void IC::PostPatching(Address address, Code* target, Code* old_target) { if (FLAG_type_info_threshold == 0 && !FLAG_watch_ic_patching) { return; } Code* host = target->GetHeap()->isolate()-> inner_pointer_to_code_cache()->GetCacheEntry(address)->code; if (host->kind() != Code::FUNCTION) return; if (FLAG_type_info_threshold > 0 && old_target->is_inline_cache_stub() && target->is_inline_cache_stub()) { int delta = ComputeTypeInfoCountDelta(old_target->ic_state(), target->ic_state()); // Not all Code objects have TypeFeedbackInfo. if (host->type_feedback_info()->IsTypeFeedbackInfo() && delta != 0) { TypeFeedbackInfo* info = TypeFeedbackInfo::cast(host->type_feedback_info()); info->change_ic_with_type_info_count(delta); } } if (host->type_feedback_info()->IsTypeFeedbackInfo()) { TypeFeedbackInfo* info = TypeFeedbackInfo::cast(host->type_feedback_info()); info->change_own_type_change_checksum(); } if (FLAG_watch_ic_patching) { host->set_profiler_ticks(0); Isolate::Current()->runtime_profiler()->NotifyICChanged(); } // TODO(2029): When an optimized function is patched, it would // be nice to propagate the corresponding type information to its // unoptimized version for the benefit of later inlining. } void IC::Clear(Address address) { Code* target = GetTargetAtAddress(address); // Don't clear debug break inline cache as it will remove the break point. if (target->ic_state() == DEBUG_BREAK) return; switch (target->kind()) { case Code::LOAD_IC: return LoadIC::Clear(address, target); case Code::KEYED_LOAD_IC: return KeyedLoadIC::Clear(address, target); case Code::STORE_IC: return StoreIC::Clear(address, target); case Code::KEYED_STORE_IC: return KeyedStoreIC::Clear(address, target); case Code::CALL_IC: return CallIC::Clear(address, target); case Code::KEYED_CALL_IC: return KeyedCallIC::Clear(address, target); case Code::COMPARE_IC: return CompareIC::Clear(address, target); case Code::UNARY_OP_IC: case Code::BINARY_OP_IC: case Code::TO_BOOLEAN_IC: // Clearing these is tricky and does not // make any performance difference. return; default: UNREACHABLE(); } } void CallICBase::Clear(Address address, Code* target) { if (target->ic_state() == UNINITIALIZED) return; bool contextual = CallICBase::Contextual::decode(target->extra_ic_state()); Code* code = Isolate::Current()->stub_cache()->FindCallInitialize( target->arguments_count(), contextual ? RelocInfo::CODE_TARGET_CONTEXT : RelocInfo::CODE_TARGET, target->kind()); SetTargetAtAddress(address, code); } void KeyedLoadIC::Clear(Address address, Code* target) { if (target->ic_state() == UNINITIALIZED) return; // Make sure to also clear the map used in inline fast cases. If we // do not clear these maps, cached code can keep objects alive // through the embedded maps. SetTargetAtAddress(address, initialize_stub()); } void LoadIC::Clear(Address address, Code* target) { if (target->ic_state() == UNINITIALIZED) return; SetTargetAtAddress(address, initialize_stub()); } void StoreIC::Clear(Address address, Code* target) { if (target->ic_state() == UNINITIALIZED) return; SetTargetAtAddress(address, (Code::GetStrictMode(target->extra_ic_state()) == kStrictMode) ? initialize_stub_strict() : initialize_stub()); } void KeyedStoreIC::Clear(Address address, Code* target) { if (target->ic_state() == UNINITIALIZED) return; SetTargetAtAddress(address, (Code::GetStrictMode(target->extra_ic_state()) == kStrictMode) ? initialize_stub_strict() : initialize_stub()); } void CompareIC::Clear(Address address, Code* target) { // Only clear ICCompareStubs, we currently cannot clear generic CompareStubs. if (target->major_key() != CodeStub::CompareIC) return; // Only clear CompareICs that can retain objects. if (target->compare_state() != KNOWN_OBJECTS) return; Token::Value op = CompareIC::ComputeOperation(target); SetTargetAtAddress(address, GetRawUninitialized(op)); PatchInlinedSmiCode(address, DISABLE_INLINED_SMI_CHECK); } static bool HasInterceptorGetter(JSObject* object) { return !object->GetNamedInterceptor()->getter()->IsUndefined(); } static void LookupForRead(Handle object, Handle name, LookupResult* lookup) { // Skip all the objects with named interceptors, but // without actual getter. while (true) { object->Lookup(*name, lookup); // Besides normal conditions (property not found or it's not // an interceptor), bail out if lookup is not cacheable: we won't // be able to IC it anyway and regular lookup should work fine. if (!lookup->IsInterceptor() || !lookup->IsCacheable()) { return; } Handle holder(lookup->holder()); if (HasInterceptorGetter(*holder)) { return; } holder->LocalLookupRealNamedProperty(*name, lookup); if (lookup->IsFound()) { ASSERT(!lookup->IsInterceptor()); return; } Handle proto(holder->GetPrototype()); if (proto->IsNull()) { ASSERT(!lookup->IsFound()); return; } object = proto; } } Handle CallICBase::TryCallAsFunction(Handle object) { Handle delegate = Execution::GetFunctionDelegate(object); if (delegate->IsJSFunction() && !object->IsJSFunctionProxy()) { // Patch the receiver and use the delegate as the function to // invoke. This is used for invoking objects as if they were functions. const int argc = target()->arguments_count(); StackFrameLocator locator; JavaScriptFrame* frame = locator.FindJavaScriptFrame(0); int index = frame->ComputeExpressionsCount() - (argc + 1); frame->SetExpression(index, *object); } return delegate; } void CallICBase::ReceiverToObjectIfRequired(Handle callee, Handle object) { while (callee->IsJSFunctionProxy()) { callee = Handle(JSFunctionProxy::cast(*callee)->call_trap()); } if (callee->IsJSFunction()) { Handle function = Handle::cast(callee); if (!function->shared()->is_classic_mode() || function->IsBuiltin()) { // Do not wrap receiver for strict mode functions or for builtins. return; } } // And only wrap string, number or boolean. if (object->IsString() || object->IsNumber() || object->IsBoolean()) { // Change the receiver to the result of calling ToObject on it. const int argc = this->target()->arguments_count(); StackFrameLocator locator; JavaScriptFrame* frame = locator.FindJavaScriptFrame(0); int index = frame->ComputeExpressionsCount() - (argc + 1); frame->SetExpression(index, *isolate()->factory()->ToObject(object)); } } MaybeObject* CallICBase::LoadFunction(State state, Code::ExtraICState extra_ic_state, Handle object, Handle name) { // If the object is undefined or null it's illegal to try to get any // of its properties; throw a TypeError in that case. if (object->IsUndefined() || object->IsNull()) { return TypeError("non_object_property_call", object, name); } // Check if the name is trivially convertible to an index and get // the element if so. uint32_t index; if (name->AsArrayIndex(&index)) { Handle result = Object::GetElement(object, index); RETURN_IF_EMPTY_HANDLE(isolate(), result); if (result->IsJSFunction()) return *result; // Try to find a suitable function delegate for the object at hand. result = TryCallAsFunction(result); if (result->IsJSFunction()) return *result; // Otherwise, it will fail in the lookup step. } // Lookup the property in the object. LookupResult lookup(isolate()); LookupForRead(object, name, &lookup); if (!lookup.IsFound()) { // If the object does not have the requested property, check which // exception we need to throw. return IsContextual(object) ? ReferenceError("not_defined", name) : TypeError("undefined_method", object, name); } // Lookup is valid: Update inline cache and stub cache. if (FLAG_use_ic) { UpdateCaches(&lookup, state, extra_ic_state, object, name); } // Get the property. PropertyAttributes attr; Handle result = Object::GetProperty(object, object, &lookup, name, &attr); RETURN_IF_EMPTY_HANDLE(isolate(), result); if (lookup.IsInterceptor() && attr == ABSENT) { // If the object does not have the requested property, check which // exception we need to throw. return IsContextual(object) ? ReferenceError("not_defined", name) : TypeError("undefined_method", object, name); } ASSERT(!result->IsTheHole()); // Make receiver an object if the callee requires it. Strict mode or builtin // functions do not wrap the receiver, non-strict functions and objects // called as functions do. ReceiverToObjectIfRequired(result, object); if (result->IsJSFunction()) { Handle function = Handle::cast(result); #ifdef ENABLE_DEBUGGER_SUPPORT // Handle stepping into a function if step into is active. Debug* debug = isolate()->debug(); if (debug->StepInActive()) { // Protect the result in a handle as the debugger can allocate and might // cause GC. debug->HandleStepIn(function, object, fp(), false); } #endif return *function; } // Try to find a suitable function delegate for the object at hand. result = TryCallAsFunction(result); if (result->IsJSFunction()) return *result; return TypeError("property_not_function", object, name); } bool CallICBase::TryUpdateExtraICState(LookupResult* lookup, Handle object, Code::ExtraICState* extra_ic_state) { ASSERT(kind_ == Code::CALL_IC); if (lookup->type() != CONSTANT_FUNCTION) return false; JSFunction* function = lookup->GetConstantFunction(); if (!function->shared()->HasBuiltinFunctionId()) return false; // Fetch the arguments passed to the called function. const int argc = target()->arguments_count(); Address entry = isolate()->c_entry_fp(isolate()->thread_local_top()); Address fp = Memory::Address_at(entry + ExitFrameConstants::kCallerFPOffset); Arguments args(argc + 1, &Memory::Object_at(fp + StandardFrameConstants::kCallerSPOffset + argc * kPointerSize)); switch (function->shared()->builtin_function_id()) { case kStringCharCodeAt: case kStringCharAt: if (object->IsString()) { String* string = String::cast(*object); // Check there's the right string value or wrapper in the receiver slot. ASSERT(string == args[0] || string == JSValue::cast(args[0])->value()); // If we're in the default (fastest) state and the index is // out of bounds, update the state to record this fact. if (StringStubState::decode(*extra_ic_state) == DEFAULT_STRING_STUB && argc >= 1 && args[1]->IsNumber()) { double index = DoubleToInteger(args.number_at(1)); if (index < 0 || index >= string->length()) { *extra_ic_state = StringStubState::update(*extra_ic_state, STRING_INDEX_OUT_OF_BOUNDS); return true; } } } break; default: return false; } return false; } Handle CallICBase::ComputeMonomorphicStub(LookupResult* lookup, State state, Code::ExtraICState extra_state, Handle object, Handle name) { int argc = target()->arguments_count(); Handle holder(lookup->holder()); switch (lookup->type()) { case FIELD: { int index = lookup->GetFieldIndex(); return isolate()->stub_cache()->ComputeCallField( argc, kind_, extra_state, name, object, holder, index); } case CONSTANT_FUNCTION: { // Get the constant function and compute the code stub for this // call; used for rewriting to monomorphic state and making sure // that the code stub is in the stub cache. Handle function(lookup->GetConstantFunction()); return isolate()->stub_cache()->ComputeCallConstant( argc, kind_, extra_state, name, object, holder, function); } case NORMAL: { // If we return a null handle, the IC will not be patched. if (!object->IsJSObject()) return Handle::null(); Handle receiver = Handle::cast(object); if (holder->IsGlobalObject()) { Handle global = Handle::cast(holder); Handle cell(global->GetPropertyCell(lookup)); if (!cell->value()->IsJSFunction()) return Handle::null(); Handle function(JSFunction::cast(cell->value())); return isolate()->stub_cache()->ComputeCallGlobal( argc, kind_, extra_state, name, receiver, global, cell, function); } else { // There is only one shared stub for calling normalized // properties. It does not traverse the prototype chain, so the // property must be found in the receiver for the stub to be // applicable. if (!holder.is_identical_to(receiver)) return Handle::null(); return isolate()->stub_cache()->ComputeCallNormal( argc, kind_, extra_state, IsQmlGlobal(holder)); } break; } case INTERCEPTOR: ASSERT(HasInterceptorGetter(*holder)); return isolate()->stub_cache()->ComputeCallInterceptor( argc, kind_, extra_state, name, object, holder); default: return Handle::null(); } } void CallICBase::UpdateCaches(LookupResult* lookup, State state, Code::ExtraICState extra_ic_state, Handle object, Handle name) { // Bail out if we didn't find a result. if (!lookup->IsProperty() || !lookup->IsCacheable()) return; if (lookup->holder() != *object && HasNormalObjectsInPrototypeChain( isolate(), lookup, object->GetPrototype())) { // Suppress optimization for prototype chains with slow properties objects // in the middle. return; } // Compute the number of arguments. int argc = target()->arguments_count(); bool had_proto_failure = false; Handle code; if (state == UNINITIALIZED) { // This is the first time we execute this inline cache. // Set the target to the pre monomorphic stub to delay // setting the monomorphic state. code = isolate()->stub_cache()->ComputeCallPreMonomorphic( argc, kind_, extra_ic_state); } else if (state == MONOMORPHIC) { if (kind_ == Code::CALL_IC && TryUpdateExtraICState(lookup, object, &extra_ic_state)) { code = ComputeMonomorphicStub(lookup, state, extra_ic_state, object, name); } else if (kind_ == Code::CALL_IC && TryRemoveInvalidPrototypeDependentStub(target(), *object, *name)) { had_proto_failure = true; code = ComputeMonomorphicStub(lookup, state, extra_ic_state, object, name); } else { code = isolate()->stub_cache()->ComputeCallMegamorphic( argc, kind_, extra_ic_state); } } else { code = ComputeMonomorphicStub(lookup, state, extra_ic_state, object, name); } // If there's no appropriate stub we simply avoid updating the caches. if (code.is_null()) return; // Patch the call site depending on the state of the cache. if (state == UNINITIALIZED || state == PREMONOMORPHIC || state == MONOMORPHIC || state == MONOMORPHIC_PROTOTYPE_FAILURE) { set_target(*code); } else if (state == MEGAMORPHIC) { // Cache code holding map should be consistent with // GenerateMonomorphicCacheProbe. It is not the map which holds the stub. Handle cache_object = object->IsJSObject() ? Handle::cast(object) : Handle(JSObject::cast(object->GetPrototype())); // Update the stub cache. isolate()->stub_cache()->Set(*name, cache_object->map(), *code); } if (had_proto_failure) state = MONOMORPHIC_PROTOTYPE_FAILURE; TRACE_IC(kind_ == Code::CALL_IC ? "CallIC" : "KeyedCallIC", name, state, target()); } MaybeObject* KeyedCallIC::LoadFunction(State state, Handle object, Handle key) { if (key->IsSymbol()) { return CallICBase::LoadFunction(state, Code::kNoExtraICState, object, Handle::cast(key)); } if (object->IsUndefined() || object->IsNull()) { return TypeError("non_object_property_call", object, key); } if (FLAG_use_ic && state != MEGAMORPHIC && object->IsHeapObject()) { int argc = target()->arguments_count(); Handle map = isolate()->factory()->non_strict_arguments_elements_map(); if (object->IsJSObject() && Handle::cast(object)->elements()->map() == *map) { Handle code = isolate()->stub_cache()->ComputeCallArguments( argc, Code::KEYED_CALL_IC); set_target(*code); TRACE_IC("KeyedCallIC", key, state, target()); } else if (!object->IsAccessCheckNeeded()) { Handle code = isolate()->stub_cache()->ComputeCallMegamorphic( argc, Code::KEYED_CALL_IC, Code::kNoExtraICState); set_target(*code); TRACE_IC("KeyedCallIC", key, state, target()); } } Handle result = GetProperty(object, key); RETURN_IF_EMPTY_HANDLE(isolate(), result); // Make receiver an object if the callee requires it. Strict mode or builtin // functions do not wrap the receiver, non-strict functions and objects // called as functions do. ReceiverToObjectIfRequired(result, object); if (result->IsJSFunction()) return *result; result = TryCallAsFunction(result); if (result->IsJSFunction()) return *result; return TypeError("property_not_function", object, key); } MaybeObject* LoadIC::Load(State state, Handle object, Handle name) { // If the object is undefined or null it's illegal to try to get any // of its properties; throw a TypeError in that case. if (object->IsUndefined() || object->IsNull()) { return TypeError("non_object_property_load", object, name); } if (FLAG_use_ic) { // Use specialized code for getting the length of strings and // string wrapper objects. The length property of string wrapper // objects is read-only and therefore always returns the length of // the underlying string value. See ECMA-262 15.5.5.1. if ((object->IsString() || object->IsStringWrapper()) && name->Equals(isolate()->heap()->length_symbol())) { Handle stub; if (state == UNINITIALIZED) { stub = pre_monomorphic_stub(); } else if (state == PREMONOMORPHIC) { stub = object->IsString() ? isolate()->builtins()->LoadIC_StringLength() : isolate()->builtins()->LoadIC_StringWrapperLength(); } else if (state == MONOMORPHIC && object->IsStringWrapper()) { stub = isolate()->builtins()->LoadIC_StringWrapperLength(); } else if (state != MEGAMORPHIC) { stub = megamorphic_stub(); } if (!stub.is_null()) { set_target(*stub); #ifdef DEBUG if (FLAG_trace_ic) PrintF("[LoadIC : +#length /string]\n"); #endif } // Get the string if we have a string wrapper object. Handle string = object->IsJSValue() ? Handle(Handle::cast(object)->value()) : object; return Smi::FromInt(String::cast(*string)->length()); } // Use specialized code for getting the length of arrays. if (object->IsJSArray() && name->Equals(isolate()->heap()->length_symbol())) { Handle stub; if (state == UNINITIALIZED) { stub = pre_monomorphic_stub(); } else if (state == PREMONOMORPHIC) { stub = isolate()->builtins()->LoadIC_ArrayLength(); } else if (state != MEGAMORPHIC) { stub = megamorphic_stub(); } if (!stub.is_null()) { set_target(*stub); #ifdef DEBUG if (FLAG_trace_ic) PrintF("[LoadIC : +#length /array]\n"); #endif } return JSArray::cast(*object)->length(); } // Use specialized code for getting prototype of functions. if (object->IsJSFunction() && name->Equals(isolate()->heap()->prototype_symbol()) && Handle::cast(object)->should_have_prototype()) { Handle stub; if (state == UNINITIALIZED) { stub = pre_monomorphic_stub(); } else if (state == PREMONOMORPHIC) { stub = isolate()->builtins()->LoadIC_FunctionPrototype(); } else if (state != MEGAMORPHIC) { stub = megamorphic_stub(); } if (!stub.is_null()) { set_target(*stub); #ifdef DEBUG if (FLAG_trace_ic) PrintF("[LoadIC : +#prototype /function]\n"); #endif } return Accessors::FunctionGetPrototype(*object, 0); } } // Check if the name is trivially convertible to an index and get // the element if so. uint32_t index; if (name->AsArrayIndex(&index)) return object->GetElement(index); // Named lookup in the object. LookupResult lookup(isolate()); LookupForRead(object, name, &lookup); // If we did not find a property, check if we need to throw an exception. if (!lookup.IsFound()) { if (IsContextual(object)) { return ReferenceError("not_defined", name); } LOG(isolate(), SuspectReadEvent(*name, *object)); } // Update inline cache and stub cache. if (FLAG_use_ic) { UpdateCaches(&lookup, state, object, name); } PropertyAttributes attr; if (lookup.IsInterceptor() || lookup.IsHandler()) { // Get the property. Handle result = Object::GetProperty(object, object, &lookup, name, &attr); RETURN_IF_EMPTY_HANDLE(isolate(), result); // If the property is not present, check if we need to throw an // exception. if (attr == ABSENT && IsContextual(object)) { return ReferenceError("not_defined", name); } return *result; } // Get the property. return object->GetProperty(*object, &lookup, *name, &attr); } void LoadIC::UpdateCaches(LookupResult* lookup, State state, Handle object, Handle name) { // Bail out if the result is not cacheable. if (!lookup->IsCacheable()) return; // Loading properties from values is not common, so don't try to // deal with non-JS objects here. if (!object->IsJSObject()) return; Handle receiver = Handle::cast(object); if (HasNormalObjectsInPrototypeChain(isolate(), lookup, *object)) return; // Compute the code stub for this load. Handle code; if (state == UNINITIALIZED) { // This is the first time we execute this inline cache. // Set the target to the pre monomorphic stub to delay // setting the monomorphic state. code = pre_monomorphic_stub(); } else if (!lookup->IsProperty()) { // Nonexistent property. The result is undefined. code = isolate()->stub_cache()->ComputeLoadNonexistent(name, receiver); } else { // Compute monomorphic stub. Handle holder(lookup->holder()); switch (lookup->type()) { case FIELD: code = isolate()->stub_cache()->ComputeLoadField( name, receiver, holder, lookup->GetFieldIndex()); break; case CONSTANT_FUNCTION: { Handle constant(lookup->GetConstantFunction()); code = isolate()->stub_cache()->ComputeLoadConstant( name, receiver, holder, constant); break; } case NORMAL: if (holder->IsGlobalObject()) { Handle global = Handle::cast(holder); Handle cell(global->GetPropertyCell(lookup)); code = isolate()->stub_cache()->ComputeLoadGlobal( name, receiver, global, cell, lookup->IsDontDelete()); } else { // There is only one shared stub for loading normalized // properties. It does not traverse the prototype chain, so the // property must be found in the receiver for the stub to be // applicable. if (!holder.is_identical_to(receiver)) return; code = isolate()->stub_cache()->ComputeLoadNormal(); } break; case CALLBACKS: { #ifdef _WIN32_WCE // Disable optimization for wince as the calling convention looks different. return; #endif Handle callback(lookup->GetCallbackObject()); if (callback->IsAccessorInfo()) { Handle info = Handle::cast(callback); if (v8::ToCData
(info->getter()) == 0) return; if (!info->IsCompatibleReceiver(*receiver)) return; code = isolate()->stub_cache()->ComputeLoadCallback( name, receiver, holder, info); } else if (callback->IsAccessorPair()) { Handle getter(Handle::cast(callback)->getter()); if (!getter->IsJSFunction()) return; if (holder->IsGlobalObject()) return; if (!holder->HasFastProperties()) return; code = isolate()->stub_cache()->ComputeLoadViaGetter( name, receiver, holder, Handle::cast(getter)); } else { ASSERT(callback->IsForeign()); // No IC support for old-style native accessors. return; } break; } case INTERCEPTOR: ASSERT(HasInterceptorGetter(*holder)); code = isolate()->stub_cache()->ComputeLoadInterceptor( name, receiver, holder); break; default: return; } } // Patch the call site depending on the state of the cache. if (state == UNINITIALIZED || state == PREMONOMORPHIC || state == MONOMORPHIC_PROTOTYPE_FAILURE) { set_target(*code); } else if (state == MONOMORPHIC) { // We are transitioning from monomorphic to megamorphic case. // Place the current monomorphic stub and stub compiled for // the receiver into stub cache. Map* map = target()->FindFirstMap(); if (map != NULL) { isolate()->stub_cache()->Set(*name, map, target()); } isolate()->stub_cache()->Set(*name, receiver->map(), *code); set_target(*megamorphic_stub()); } else if (state == MEGAMORPHIC) { // Cache code holding map should be consistent with // GenerateMonomorphicCacheProbe. isolate()->stub_cache()->Set(*name, receiver->map(), *code); } TRACE_IC("LoadIC", name, state, target()); } Handle KeyedLoadIC::GetElementStubWithoutMapCheck( bool is_js_array, ElementsKind elements_kind, KeyedAccessGrowMode grow_mode) { ASSERT(grow_mode == DO_NOT_ALLOW_JSARRAY_GROWTH); return KeyedLoadElementStub(elements_kind).GetCode(); } Handle KeyedLoadIC::ComputePolymorphicStub( MapHandleList* receiver_maps, StrictModeFlag strict_mode, KeyedAccessGrowMode growth_mode) { CodeHandleList handler_ics(receiver_maps->length()); for (int i = 0; i < receiver_maps->length(); ++i) { Handle receiver_map = receiver_maps->at(i); Handle cached_stub = ComputeMonomorphicStubWithoutMapCheck( receiver_map, strict_mode, growth_mode); handler_ics.Add(cached_stub); } KeyedLoadStubCompiler compiler(isolate()); Handle code = compiler.CompileLoadPolymorphic( receiver_maps, &handler_ics); isolate()->counters()->keyed_load_polymorphic_stubs()->Increment(); PROFILE(isolate(), CodeCreateEvent(Logger::KEYED_LOAD_MEGAMORPHIC_IC_TAG, *code, 0)); return code; } static Handle TryConvertKey(Handle key, Isolate* isolate) { // This helper implements a few common fast cases for converting // non-smi keys of keyed loads/stores to a smi or a string. if (key->IsHeapNumber()) { double value = Handle::cast(key)->value(); if (isnan(value)) { key = isolate->factory()->nan_symbol(); } else { int int_value = FastD2I(value); if (value == int_value && Smi::IsValid(int_value)) { key = Handle(Smi::FromInt(int_value)); } } } else if (key->IsUndefined()) { key = isolate->factory()->undefined_symbol(); } return key; } MaybeObject* KeyedLoadIC::Load(State state, Handle object, Handle key, bool force_generic_stub) { // Check for values that can be converted into a symbol directly or // is representable as a smi. key = TryConvertKey(key, isolate()); if (key->IsSymbol()) { Handle name = Handle::cast(key); // If the object is undefined or null it's illegal to try to get any // of its properties; throw a TypeError in that case. if (object->IsUndefined() || object->IsNull()) { return TypeError("non_object_property_load", object, name); } if (FLAG_use_ic) { // TODO(1073): don't ignore the current stub state. // Use specialized code for getting the length of strings. if (object->IsString() && name->Equals(isolate()->heap()->length_symbol())) { Handle string = Handle::cast(object); Handle code = isolate()->stub_cache()->ComputeKeyedLoadStringLength(name, string); ASSERT(!code.is_null()); set_target(*code); TRACE_IC("KeyedLoadIC", name, state, target()); return Smi::FromInt(string->length()); } // Use specialized code for getting the length of arrays. if (object->IsJSArray() && name->Equals(isolate()->heap()->length_symbol())) { Handle array = Handle::cast(object); Handle code = isolate()->stub_cache()->ComputeKeyedLoadArrayLength(name, array); ASSERT(!code.is_null()); set_target(*code); TRACE_IC("KeyedLoadIC", name, state, target()); return array->length(); } // Use specialized code for getting prototype of functions. if (object->IsJSFunction() && name->Equals(isolate()->heap()->prototype_symbol()) && Handle::cast(object)->should_have_prototype()) { Handle function = Handle::cast(object); Handle code = isolate()->stub_cache()->ComputeKeyedLoadFunctionPrototype( name, function); ASSERT(!code.is_null()); set_target(*code); TRACE_IC("KeyedLoadIC", name, state, target()); return Accessors::FunctionGetPrototype(*object, 0); } } // Check if the name is trivially convertible to an index and get // the element or char if so. uint32_t index = 0; if (name->AsArrayIndex(&index)) { // Rewrite to the generic keyed load stub. if (FLAG_use_ic) set_target(*generic_stub()); return Runtime::GetElementOrCharAt(isolate(), object, index); } // Named lookup. LookupResult lookup(isolate()); LookupForRead(object, name, &lookup); // If we did not find a property, check if we need to throw an exception. if (!lookup.IsFound() && IsContextual(object)) { return ReferenceError("not_defined", name); } if (FLAG_use_ic) { UpdateCaches(&lookup, state, object, name); } PropertyAttributes attr; if (lookup.IsInterceptor()) { // Get the property. Handle result = Object::GetProperty(object, object, &lookup, name, &attr); RETURN_IF_EMPTY_HANDLE(isolate(), result); // If the property is not present, check if we need to throw an // exception. if (attr == ABSENT && IsContextual(object)) { return ReferenceError("not_defined", name); } return *result; } return object->GetProperty(*object, &lookup, *name, &attr); } // Do not use ICs for objects that require access checks (including // the global object). bool use_ic = FLAG_use_ic && !object->IsAccessCheckNeeded(); if (use_ic) { Handle stub = generic_stub(); if (!force_generic_stub) { if (object->IsString() && key->IsNumber()) { if (state == UNINITIALIZED) { stub = string_stub(); } } else if (object->IsJSObject()) { Handle receiver = Handle::cast(object); if (receiver->elements()->map() == isolate()->heap()->non_strict_arguments_elements_map()) { stub = non_strict_arguments_stub(); } else if (receiver->HasIndexedInterceptor()) { stub = indexed_interceptor_stub(); } else if (key->IsSmi() && (target() != *non_strict_arguments_stub())) { stub = ComputeStub(receiver, LOAD, kNonStrictMode, stub); } } } else { TRACE_GENERIC_IC("KeyedLoadIC", "force generic"); } if (!stub.is_null()) set_target(*stub); } TRACE_IC("KeyedLoadIC", key, state, target()); // Get the property. return Runtime::GetObjectProperty(isolate(), object, key); } void KeyedLoadIC::UpdateCaches(LookupResult* lookup, State state, Handle object, Handle name) { // Bail out if we didn't find a result. if (!lookup->IsProperty() || !lookup->IsCacheable()) return; if (!object->IsJSObject()) return; Handle receiver = Handle::cast(object); if (HasNormalObjectsInPrototypeChain(isolate(), lookup, *object)) return; // Compute the code stub for this load. Handle code; if (state == UNINITIALIZED) { // This is the first time we execute this inline cache. // Set the target to the pre monomorphic stub to delay // setting the monomorphic state. code = pre_monomorphic_stub(); } else { // Compute a monomorphic stub. Handle holder(lookup->holder()); switch (lookup->type()) { case FIELD: code = isolate()->stub_cache()->ComputeKeyedLoadField( name, receiver, holder, lookup->GetFieldIndex()); break; case CONSTANT_FUNCTION: { Handle constant(lookup->GetConstantFunction()); code = isolate()->stub_cache()->ComputeKeyedLoadConstant( name, receiver, holder, constant); break; } case CALLBACKS: { Handle callback_object(lookup->GetCallbackObject()); if (!callback_object->IsAccessorInfo()) return; Handle callback = Handle::cast(callback_object); if (v8::ToCData
(callback->getter()) == 0) return; if (!callback->IsCompatibleReceiver(*receiver)) return; code = isolate()->stub_cache()->ComputeKeyedLoadCallback( name, receiver, holder, callback); break; } case INTERCEPTOR: ASSERT(HasInterceptorGetter(lookup->holder())); code = isolate()->stub_cache()->ComputeKeyedLoadInterceptor( name, receiver, holder); break; default: // Always rewrite to the generic case so that we do not // repeatedly try to rewrite. code = generic_stub(); break; } } // Patch the call site depending on the state of the cache. Make // sure to always rewrite from monomorphic to megamorphic. ASSERT(state != MONOMORPHIC_PROTOTYPE_FAILURE); if (state == UNINITIALIZED || state == PREMONOMORPHIC) { set_target(*code); } else if (state == MONOMORPHIC) { set_target(*megamorphic_stub()); } TRACE_IC("KeyedLoadIC", name, state, target()); } static bool StoreICableLookup(LookupResult* lookup) { // Bail out if we didn't find a result. if (!lookup->IsFound()) return false; // Bail out if inline caching is not allowed. if (!lookup->IsCacheable()) return false; // If the property is read-only, we leave the IC in its current state. if (lookup->IsTransition()) { return !lookup->GetTransitionDetails().IsReadOnly(); } return !lookup->IsReadOnly(); } static bool LookupForWrite(Handle receiver, Handle name, LookupResult* lookup) { receiver->LocalLookup(*name, lookup); if (!lookup->IsFound()) { receiver->map()->LookupTransition(*receiver, *name, lookup); } if (!StoreICableLookup(lookup)) { // 2nd chance: There can be accessors somewhere in the prototype chain. receiver->Lookup(*name, lookup); return lookup->IsPropertyCallbacks() && StoreICableLookup(lookup); } if (lookup->IsInterceptor() && receiver->GetNamedInterceptor()->setter()->IsUndefined()) { receiver->LocalLookupRealNamedProperty(*name, lookup); return StoreICableLookup(lookup); } return true; } MaybeObject* StoreIC::Store(State state, StrictModeFlag strict_mode, Handle object, Handle name, Handle value) { if (!object->IsJSObject()) { // Handle proxies. if (object->IsJSProxy()) { return JSProxy::cast(*object)-> SetProperty(*name, *value, NONE, strict_mode); } // If the object is undefined or null it's illegal to try to set any // properties on it; throw a TypeError in that case. if (object->IsUndefined() || object->IsNull()) { return TypeError("non_object_property_store", object, name); } // The length property of string values is read-only. Throw in strict mode. if (strict_mode == kStrictMode && object->IsString() && name->Equals(isolate()->heap()->length_symbol())) { return TypeError("strict_read_only_property", object, name); } // Ignore other stores where the receiver is not a JSObject. // TODO(1475): Must check prototype chains of object wrappers. return *value; } Handle receiver = Handle::cast(object); // Check if the given name is an array index. uint32_t index; if (name->AsArrayIndex(&index)) { Handle result = JSObject::SetElement(receiver, index, value, NONE, strict_mode); RETURN_IF_EMPTY_HANDLE(isolate(), result); return *value; } // Observed objects are always modified through the runtime. if (FLAG_harmony_observation && receiver->map()->is_observed()) { return receiver->SetProperty(*name, *value, NONE, strict_mode); } // Use specialized code for setting the length of arrays with fast // properties. Slow properties might indicate redefinition of the // length property. if (receiver->IsJSArray() && name->Equals(isolate()->heap()->length_symbol()) && Handle::cast(receiver)->AllowsSetElementsLength() && receiver->HasFastProperties()) { #ifdef DEBUG if (FLAG_trace_ic) PrintF("[StoreIC : +#length /array]\n"); #endif Handle stub = (strict_mode == kStrictMode) ? isolate()->builtins()->StoreIC_ArrayLength_Strict() : isolate()->builtins()->StoreIC_ArrayLength(); set_target(*stub); return receiver->SetProperty(*name, *value, NONE, strict_mode); } // Lookup the property locally in the receiver. if (!receiver->IsJSGlobalProxy()) { LookupResult lookup(isolate()); if (LookupForWrite(receiver, name, &lookup)) { if (FLAG_use_ic) { // Generate a stub for this store. UpdateCaches(&lookup, state, strict_mode, receiver, name, value); } } else { // Strict mode doesn't allow setting non-existent global property // or an assignment to a read only property. if (strict_mode == kStrictMode) { if (lookup.IsProperty() && lookup.IsReadOnly()) { return TypeError("strict_read_only_property", object, name); } else if (IsContextual(object)) { return ReferenceError("not_defined", name); } } } } if (receiver->IsJSGlobalProxy()) { // TODO(ulan): find out why we patch this site even with --no-use-ic // Generate a generic stub that goes to the runtime when we see a global // proxy as receiver. Handle stub = (strict_mode == kStrictMode) ? global_proxy_stub_strict() : global_proxy_stub(); if (target() != *stub) { set_target(*stub); TRACE_IC("StoreIC", name, state, target()); } } // Set the property. return receiver->SetProperty(*name, *value, NONE, strict_mode, JSReceiver::CERTAINLY_NOT_STORE_FROM_KEYED); } void StoreIC::UpdateCaches(LookupResult* lookup, State state, StrictModeFlag strict_mode, Handle receiver, Handle name, Handle value) { ASSERT(!receiver->IsJSGlobalProxy()); ASSERT(StoreICableLookup(lookup)); ASSERT(lookup->IsFound()); // These are not cacheable, so we never see such LookupResults here. ASSERT(!lookup->IsHandler()); // If the property has a non-field type allowing map transitions // where there is extra room in the object, we leave the IC in its // current state. PropertyType type = lookup->type(); // Compute the code stub for this store; used for rewriting to // monomorphic state and making sure that the code stub is in the // stub cache. Handle holder(lookup->holder()); Handle code; switch (type) { case FIELD: code = isolate()->stub_cache()->ComputeStoreField(name, receiver, lookup->GetFieldIndex(), Handle::null(), strict_mode); break; case NORMAL: if (receiver->IsGlobalObject()) { // The stub generated for the global object picks the value directly // from the property cell. So the property must be directly on the // global object. Handle global = Handle::cast(receiver); Handle cell(global->GetPropertyCell(lookup)); code = isolate()->stub_cache()->ComputeStoreGlobal( name, global, cell, strict_mode); } else { if (!holder.is_identical_to(receiver)) return; code = isolate()->stub_cache()->ComputeStoreNormal(strict_mode); } break; case CALLBACKS: { Handle callback(lookup->GetCallbackObject()); if (callback->IsAccessorInfo()) { Handle info = Handle::cast(callback); if (v8::ToCData
(info->setter()) == 0) return; if (!holder->HasFastProperties()) return; if (!info->IsCompatibleReceiver(*receiver)) return; code = isolate()->stub_cache()->ComputeStoreCallback( name, receiver, holder, info, strict_mode); } else if (callback->IsAccessorPair()) { Handle setter(Handle::cast(callback)->setter()); if (!setter->IsJSFunction()) return; if (holder->IsGlobalObject()) return; if (!holder->HasFastProperties()) return; code = isolate()->stub_cache()->ComputeStoreViaSetter( name, receiver, holder, Handle::cast(setter), strict_mode); } else { ASSERT(callback->IsForeign()); // No IC support for old-style native accessors. return; } break; } case INTERCEPTOR: ASSERT(!receiver->GetNamedInterceptor()->setter()->IsUndefined()); code = isolate()->stub_cache()->ComputeStoreInterceptor( name, receiver, strict_mode); break; case CONSTANT_FUNCTION: return; case TRANSITION: { Handle transition(lookup->GetTransitionTarget()); int descriptor = transition->LastAdded(); DescriptorArray* target_descriptors = transition->instance_descriptors(); PropertyDetails details = target_descriptors->GetDetails(descriptor); if (details.type() != FIELD || details.attributes() != NONE) return; int field_index = target_descriptors->GetFieldIndex(descriptor); code = isolate()->stub_cache()->ComputeStoreField( name, receiver, field_index, transition, strict_mode); break; } case NONEXISTENT: case HANDLER: UNREACHABLE(); return; } // Patch the call site depending on the state of the cache. if (state == UNINITIALIZED || state == MONOMORPHIC_PROTOTYPE_FAILURE) { set_target(*code); } else if (state == MONOMORPHIC) { // Only move to megamorphic if the target changes. if (target() != *code) { set_target((strict_mode == kStrictMode) ? megamorphic_stub_strict() : megamorphic_stub()); } } else if (state == MEGAMORPHIC) { // Update the stub cache. isolate()->stub_cache()->Set(*name, receiver->map(), *code); } TRACE_IC("StoreIC", name, state, target()); } static bool AddOneReceiverMapIfMissing(MapHandleList* receiver_maps, Handle new_receiver_map) { ASSERT(!new_receiver_map.is_null()); for (int current = 0; current < receiver_maps->length(); ++current) { if (!receiver_maps->at(current).is_null() && receiver_maps->at(current).is_identical_to(new_receiver_map)) { return false; } } receiver_maps->Add(new_receiver_map); return true; } void KeyedIC::GetReceiverMapsForStub(Handle stub, MapHandleList* result) { ASSERT(stub->is_inline_cache_stub()); if (!string_stub().is_null() && stub.is_identical_to(string_stub())) { return result->Add(isolate()->factory()->string_map()); } else if (stub->is_keyed_load_stub() || stub->is_keyed_store_stub()) { if (stub->ic_state() == MONOMORPHIC) { result->Add(Handle(stub->FindFirstMap())); } else { ASSERT(stub->ic_state() == MEGAMORPHIC); AssertNoAllocation no_allocation; int mask = RelocInfo::ModeMask(RelocInfo::EMBEDDED_OBJECT); for (RelocIterator it(*stub, mask); !it.done(); it.next()) { RelocInfo* info = it.rinfo(); Handle object(info->target_object()); ASSERT(object->IsMap()); AddOneReceiverMapIfMissing(result, Handle::cast(object)); } } } } Handle KeyedIC::ComputeStub(Handle receiver, StubKind stub_kind, StrictModeFlag strict_mode, Handle generic_stub) { State ic_state = target()->ic_state(); KeyedAccessGrowMode grow_mode = IsGrowStubKind(stub_kind) ? ALLOW_JSARRAY_GROWTH : DO_NOT_ALLOW_JSARRAY_GROWTH; // Don't handle megamorphic property accesses for INTERCEPTORS or CALLBACKS // via megamorphic stubs, since they don't have a map in their relocation info // and so the stubs can't be harvested for the object needed for a map check. if (target()->type() != Code::NORMAL) { TRACE_GENERIC_IC("KeyedIC", "non-NORMAL target type"); return generic_stub; } bool monomorphic = false; bool is_transition_stub = IsTransitionStubKind(stub_kind); Handle receiver_map(receiver->map()); Handle monomorphic_map = receiver_map; MapHandleList target_receiver_maps; if (ic_state == UNINITIALIZED || ic_state == PREMONOMORPHIC) { // Optimistically assume that ICs that haven't reached the MONOMORPHIC state // yet will do so and stay there. monomorphic = true; } else { GetReceiverMapsForStub(Handle(target()), &target_receiver_maps); if (ic_state == MONOMORPHIC && (is_transition_stub || stub_kind == LOAD)) { // The first time a receiver is seen that is a transitioned version of the // previous monomorphic receiver type, assume the new ElementsKind is the // monomorphic type. This benefits global arrays that only transition // once, and all call sites accessing them are faster if they remain // monomorphic. If this optimistic assumption is not true, the IC will // miss again and it will become polymorphic and support both the // untransitioned and transitioned maps. monomorphic = IsMoreGeneralElementsKindTransition( target_receiver_maps.at(0)->elements_kind(), receiver->GetElementsKind()); } } if (monomorphic) { if (is_transition_stub) { monomorphic_map = ComputeTransitionedMap(receiver, stub_kind); ASSERT(*monomorphic_map != *receiver_map); stub_kind = GetNoTransitionStubKind(stub_kind); } return ComputeMonomorphicStub( monomorphic_map, stub_kind, strict_mode, generic_stub); } ASSERT(target() != *generic_stub); // Determine the list of receiver maps that this call site has seen, // adding the map that was just encountered. bool map_added = AddOneReceiverMapIfMissing(&target_receiver_maps, receiver_map); if (IsTransitionStubKind(stub_kind)) { Handle new_map = ComputeTransitionedMap(receiver, stub_kind); map_added |= AddOneReceiverMapIfMissing(&target_receiver_maps, new_map); } if (!map_added) { // If the miss wasn't due to an unseen map, a polymorphic stub // won't help, use the generic stub. TRACE_GENERIC_IC("KeyedIC", "same map added twice"); return generic_stub; } // If the maximum number of receiver maps has been exceeded, use the generic // version of the IC. if (target_receiver_maps.length() > kMaxKeyedPolymorphism) { TRACE_GENERIC_IC("KeyedIC", "max polymorph exceeded"); return generic_stub; } if ((Code::GetKeyedAccessGrowMode(target()->extra_ic_state()) == ALLOW_JSARRAY_GROWTH)) { grow_mode = ALLOW_JSARRAY_GROWTH; } Handle cache = isolate()->factory()->polymorphic_code_cache(); Code::ExtraICState extra_state = Code::ComputeExtraICState(grow_mode, strict_mode); Code::Flags flags = Code::ComputeFlags(kind(), MEGAMORPHIC, extra_state); Handle probe = cache->Lookup(&target_receiver_maps, flags); if (probe->IsCode()) return Handle::cast(probe); Handle stub = ComputePolymorphicStub(&target_receiver_maps, strict_mode, grow_mode); PolymorphicCodeCache::Update(cache, &target_receiver_maps, flags, stub); return stub; } Handle KeyedIC::ComputeMonomorphicStubWithoutMapCheck( Handle receiver_map, StrictModeFlag strict_mode, KeyedAccessGrowMode grow_mode) { if ((receiver_map->instance_type() & kNotStringTag) == 0) { ASSERT(!string_stub().is_null()); return string_stub(); } else { ASSERT(receiver_map->has_dictionary_elements() || receiver_map->has_fast_smi_or_object_elements() || receiver_map->has_fast_double_elements() || receiver_map->has_external_array_elements()); bool is_js_array = receiver_map->instance_type() == JS_ARRAY_TYPE; return GetElementStubWithoutMapCheck(is_js_array, receiver_map->elements_kind(), grow_mode); } } Handle KeyedIC::ComputeMonomorphicStub(Handle receiver_map, StubKind stub_kind, StrictModeFlag strict_mode, Handle generic_stub) { ElementsKind elements_kind = receiver_map->elements_kind(); if (IsFastElementsKind(elements_kind) || IsExternalArrayElementsKind(elements_kind) || IsDictionaryElementsKind(elements_kind)) { return isolate()->stub_cache()->ComputeKeyedLoadOrStoreElement( receiver_map, stub_kind, strict_mode); } else { return generic_stub; } } Handle KeyedIC::ComputeTransitionedMap(Handle receiver, StubKind stub_kind) { switch (stub_kind) { case KeyedIC::STORE_TRANSITION_SMI_TO_OBJECT: case KeyedIC::STORE_TRANSITION_DOUBLE_TO_OBJECT: case KeyedIC::STORE_AND_GROW_TRANSITION_SMI_TO_OBJECT: case KeyedIC::STORE_AND_GROW_TRANSITION_DOUBLE_TO_OBJECT: return JSObject::GetElementsTransitionMap(receiver, FAST_ELEMENTS); case KeyedIC::STORE_TRANSITION_SMI_TO_DOUBLE: case KeyedIC::STORE_AND_GROW_TRANSITION_SMI_TO_DOUBLE: return JSObject::GetElementsTransitionMap(receiver, FAST_DOUBLE_ELEMENTS); case KeyedIC::STORE_TRANSITION_HOLEY_SMI_TO_OBJECT: case KeyedIC::STORE_TRANSITION_HOLEY_DOUBLE_TO_OBJECT: case KeyedIC::STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_OBJECT: case KeyedIC::STORE_AND_GROW_TRANSITION_HOLEY_DOUBLE_TO_OBJECT: return JSObject::GetElementsTransitionMap(receiver, FAST_HOLEY_ELEMENTS); case KeyedIC::STORE_TRANSITION_HOLEY_SMI_TO_DOUBLE: case KeyedIC::STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_DOUBLE: return JSObject::GetElementsTransitionMap(receiver, FAST_HOLEY_DOUBLE_ELEMENTS); case KeyedIC::LOAD: case KeyedIC::STORE_NO_TRANSITION: case KeyedIC::STORE_AND_GROW_NO_TRANSITION: UNREACHABLE(); break; } return Handle::null(); } Handle KeyedStoreIC::GetElementStubWithoutMapCheck( bool is_js_array, ElementsKind elements_kind, KeyedAccessGrowMode grow_mode) { return KeyedStoreElementStub(is_js_array, elements_kind, grow_mode).GetCode(); } Handle KeyedStoreIC::ComputePolymorphicStub( MapHandleList* receiver_maps, StrictModeFlag strict_mode, KeyedAccessGrowMode grow_mode) { // Collect MONOMORPHIC stubs for all target_receiver_maps. CodeHandleList handler_ics(receiver_maps->length()); MapHandleList transitioned_maps(receiver_maps->length()); for (int i = 0; i < receiver_maps->length(); ++i) { Handle receiver_map(receiver_maps->at(i)); Handle cached_stub; Handle transitioned_map = receiver_map->FindTransitionedMap(receiver_maps); if (!transitioned_map.is_null()) { cached_stub = ElementsTransitionAndStoreStub( receiver_map->elements_kind(), // original elements_kind transitioned_map->elements_kind(), receiver_map->instance_type() == JS_ARRAY_TYPE, // is_js_array strict_mode, grow_mode).GetCode(); } else { cached_stub = ComputeMonomorphicStubWithoutMapCheck(receiver_map, strict_mode, grow_mode); } ASSERT(!cached_stub.is_null()); handler_ics.Add(cached_stub); transitioned_maps.Add(transitioned_map); } KeyedStoreStubCompiler compiler(isolate(), strict_mode, grow_mode); Handle code = compiler.CompileStorePolymorphic( receiver_maps, &handler_ics, &transitioned_maps); isolate()->counters()->keyed_store_polymorphic_stubs()->Increment(); PROFILE(isolate(), CodeCreateEvent(Logger::KEYED_STORE_MEGAMORPHIC_IC_TAG, *code, 0)); return code; } KeyedIC::StubKind KeyedStoreIC::GetStubKind(Handle receiver, Handle key, Handle value) { ASSERT(key->IsSmi()); int index = Smi::cast(*key)->value(); bool allow_growth = receiver->IsJSArray() && JSArray::cast(*receiver)->length()->IsSmi() && index >= Smi::cast(JSArray::cast(*receiver)->length())->value(); if (allow_growth) { // Handle growing array in stub if necessary. if (receiver->HasFastSmiElements()) { if (value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_DOUBLE; } else { return STORE_AND_GROW_TRANSITION_SMI_TO_DOUBLE; } } if (value->IsHeapObject()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_OBJECT; } else { return STORE_AND_GROW_TRANSITION_SMI_TO_OBJECT; } } } else if (receiver->HasFastDoubleElements()) { if (!value->IsSmi() && !value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_AND_GROW_TRANSITION_HOLEY_DOUBLE_TO_OBJECT; } else { return STORE_AND_GROW_TRANSITION_DOUBLE_TO_OBJECT; } } } return STORE_AND_GROW_NO_TRANSITION; } else { // Handle only in-bounds elements accesses. if (receiver->HasFastSmiElements()) { if (value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_SMI_TO_DOUBLE; } else { return STORE_TRANSITION_SMI_TO_DOUBLE; } } else if (value->IsHeapObject()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_SMI_TO_OBJECT; } else { return STORE_TRANSITION_SMI_TO_OBJECT; } } } else if (receiver->HasFastDoubleElements()) { if (!value->IsSmi() && !value->IsHeapNumber()) { if (receiver->HasFastHoleyElements()) { return STORE_TRANSITION_HOLEY_DOUBLE_TO_OBJECT; } else { return STORE_TRANSITION_DOUBLE_TO_OBJECT; } } } return STORE_NO_TRANSITION; } } MaybeObject* KeyedStoreIC::Store(State state, StrictModeFlag strict_mode, Handle object, Handle key, Handle value, bool force_generic) { // Check for values that can be converted into a symbol directly or // is representable as a smi. key = TryConvertKey(key, isolate()); if (key->IsSymbol()) { Handle name = Handle::cast(key); // Handle proxies. if (object->IsJSProxy()) { return JSProxy::cast(*object)->SetProperty( *name, *value, NONE, strict_mode); } // If the object is undefined or null it's illegal to try to set any // properties on it; throw a TypeError in that case. if (object->IsUndefined() || object->IsNull()) { return TypeError("non_object_property_store", object, name); } // Ignore stores where the receiver is not a JSObject. if (!object->IsJSObject()) return *value; Handle receiver = Handle::cast(object); // Check if the given name is an array index. uint32_t index; if (name->AsArrayIndex(&index)) { Handle result = JSObject::SetElement(receiver, index, value, NONE, strict_mode); RETURN_IF_EMPTY_HANDLE(isolate(), result); return *value; } // Update inline cache and stub cache. if (FLAG_use_ic && !receiver->IsJSGlobalProxy() && !(FLAG_harmony_observation && receiver->map()->is_observed())) { LookupResult lookup(isolate()); if (LookupForWrite(receiver, name, &lookup)) { UpdateCaches(&lookup, state, strict_mode, receiver, name, value); } } // Set the property. return receiver->SetProperty(*name, *value, NONE, strict_mode); } // Do not use ICs for objects that require access checks (including // the global object), or are observed. bool use_ic = FLAG_use_ic && !object->IsAccessCheckNeeded() && !(FLAG_harmony_observation && object->IsJSObject() && JSObject::cast(*object)->map()->is_observed()); ASSERT(!(use_ic && object->IsJSGlobalProxy())); if (use_ic) { Handle stub = (strict_mode == kStrictMode) ? generic_stub_strict() : generic_stub(); if (object->IsJSObject()) { Handle receiver = Handle::cast(object); if (receiver->elements()->map() == isolate()->heap()->non_strict_arguments_elements_map()) { stub = non_strict_arguments_stub(); } else if (!force_generic) { if (key->IsSmi() && (target() != *non_strict_arguments_stub())) { StubKind stub_kind = GetStubKind(receiver, key, value); stub = ComputeStub(receiver, stub_kind, strict_mode, stub); } } else { TRACE_GENERIC_IC("KeyedStoreIC", "force generic"); } } if (!stub.is_null()) set_target(*stub); } TRACE_IC("KeyedStoreIC", key, state, target()); // Set the property. return Runtime::SetObjectProperty( isolate(), object , key, value, NONE, strict_mode); } void KeyedStoreIC::UpdateCaches(LookupResult* lookup, State state, StrictModeFlag strict_mode, Handle receiver, Handle name, Handle value) { ASSERT(!receiver->IsJSGlobalProxy()); ASSERT(StoreICableLookup(lookup)); ASSERT(lookup->IsFound()); // These are not cacheable, so we never see such LookupResults here. ASSERT(!lookup->IsHandler()); // If the property has a non-field type allowing map transitions // where there is extra room in the object, we leave the IC in its // current state. PropertyType type = lookup->type(); // Compute the code stub for this store; used for rewriting to // monomorphic state and making sure that the code stub is in the // stub cache. Handle code; switch (type) { case FIELD: code = isolate()->stub_cache()->ComputeKeyedStoreField( name, receiver, lookup->GetFieldIndex(), Handle::null(), strict_mode); break; case TRANSITION: { Handle transition(lookup->GetTransitionTarget()); int descriptor = transition->LastAdded(); DescriptorArray* target_descriptors = transition->instance_descriptors(); PropertyDetails details = target_descriptors->GetDetails(descriptor); if (details.type() == FIELD && details.attributes() == NONE) { int field_index = target_descriptors->GetFieldIndex(descriptor); code = isolate()->stub_cache()->ComputeKeyedStoreField( name, receiver, field_index, transition, strict_mode); break; } // fall through. } case NORMAL: case CONSTANT_FUNCTION: case CALLBACKS: case INTERCEPTOR: // Always rewrite to the generic case so that we do not // repeatedly try to rewrite. code = (strict_mode == kStrictMode) ? generic_stub_strict() : generic_stub(); break; case HANDLER: case NONEXISTENT: UNREACHABLE(); return; } ASSERT(!code.is_null()); // Patch the call site depending on the state of the cache. Make // sure to always rewrite from monomorphic to megamorphic. ASSERT(state != MONOMORPHIC_PROTOTYPE_FAILURE); if (state == UNINITIALIZED || state == PREMONOMORPHIC) { set_target(*code); } else if (state == MONOMORPHIC) { set_target((strict_mode == kStrictMode) ? *megamorphic_stub_strict() : *megamorphic_stub()); } TRACE_IC("KeyedStoreIC", name, state, target()); } #undef TRACE_IC // ---------------------------------------------------------------------------- // Static IC stub generators. // // Used from ic-.cc. RUNTIME_FUNCTION(MaybeObject*, CallIC_Miss) { HandleScope scope(isolate); ASSERT(args.length() == 2); CallIC ic(isolate); IC::State state = IC::StateFrom(ic.target(), args[0], args[1]); Code::ExtraICState extra_ic_state = ic.target()->extra_ic_state(); MaybeObject* maybe_result = ic.LoadFunction(state, extra_ic_state, args.at(0), args.at(1)); // Result could be a function or a failure. JSFunction* raw_function = NULL; if (!maybe_result->To(&raw_function)) return maybe_result; // The first time the inline cache is updated may be the first time the // function it references gets called. If the function is lazily compiled // then the first call will trigger a compilation. We check for this case // and we do the compilation immediately, instead of waiting for the stub // currently attached to the JSFunction object to trigger compilation. if (raw_function->is_compiled()) return raw_function; Handle function(raw_function); JSFunction::CompileLazy(function, CLEAR_EXCEPTION); return *function; } // Used from ic-.cc. RUNTIME_FUNCTION(MaybeObject*, KeyedCallIC_Miss) { HandleScope scope(isolate); ASSERT(args.length() == 2); KeyedCallIC ic(isolate); IC::State state = IC::StateFrom(ic.target(), args[0], args[1]); MaybeObject* maybe_result = ic.LoadFunction(state, args.at(0), args.at(1)); // Result could be a function or a failure. JSFunction* raw_function = NULL; if (!maybe_result->To(&raw_function)) return maybe_result; if (raw_function->is_compiled()) return raw_function; Handle function(raw_function); JSFunction::CompileLazy(function, CLEAR_EXCEPTION); return *function; } // Used from ic-.cc. RUNTIME_FUNCTION(MaybeObject*, LoadIC_Miss) { HandleScope scope(isolate); ASSERT(args.length() == 2); LoadIC ic(isolate); IC::State state = IC::StateFrom(ic.target(), args[0], args[1]); return ic.Load(state, args.at(0), args.at(1)); } // Used from ic-.cc RUNTIME_FUNCTION(MaybeObject*, KeyedLoadIC_Miss) { HandleScope scope(isolate); ASSERT(args.length() == 2); KeyedLoadIC ic(isolate); IC::State state = IC::StateFrom(ic.target(), args[0], args[1]); return ic.Load(state, args.at(0), args.at(1), false); } RUNTIME_FUNCTION(MaybeObject*, KeyedLoadIC_MissForceGeneric) { HandleScope scope(isolate); ASSERT(args.length() == 2); KeyedLoadIC ic(isolate); IC::State state = IC::StateFrom(ic.target(), args[0], args[1]); return ic.Load(state, args.at(0), args.at(1), true); } // Used from ic-.cc. RUNTIME_FUNCTION(MaybeObject*, StoreIC_Miss) { HandleScope scope; ASSERT(args.length() == 3); StoreIC ic(isolate); IC::State state = IC::StateFrom(ic.target(), args[0], args[1]); Code::ExtraICState extra_ic_state = ic.target()->extra_ic_state(); return ic.Store(state, Code::GetStrictMode(extra_ic_state), args.at(0), args.at(1), args.at(2)); } RUNTIME_FUNCTION(MaybeObject*, StoreIC_ArrayLength) { NoHandleAllocation nha; ASSERT(args.length() == 2); JSArray* receiver = JSArray::cast(args[0]); Object* len = args[1]; // The generated code should filter out non-Smis before we get here. ASSERT(len->IsSmi()); #ifdef DEBUG // The length property has to be a writable callback property. LookupResult debug_lookup(isolate); receiver->LocalLookup(isolate->heap()->length_symbol(), &debug_lookup); ASSERT(debug_lookup.IsPropertyCallbacks() && !debug_lookup.IsReadOnly()); #endif Object* result; { MaybeObject* maybe_result = receiver->SetElementsLength(len); if (!maybe_result->ToObject(&result)) return maybe_result; } return len; } // Extend storage is called in a store inline cache when // it is necessary to extend the properties array of a // JSObject. RUNTIME_FUNCTION(MaybeObject*, SharedStoreIC_ExtendStorage) { NoHandleAllocation na; ASSERT(args.length() == 3); // Convert the parameters JSObject* object = JSObject::cast(args[0]); Map* transition = Map::cast(args[1]); Object* value = args[2]; // Check the object has run out out property space. ASSERT(object->HasFastProperties()); ASSERT(object->map()->unused_property_fields() == 0); // Expand the properties array. FixedArray* old_storage = object->properties(); int new_unused = transition->unused_property_fields(); int new_size = old_storage->length() + new_unused + 1; Object* result; { MaybeObject* maybe_result = old_storage->CopySize(new_size); if (!maybe_result->ToObject(&result)) return maybe_result; } FixedArray* new_storage = FixedArray::cast(result); new_storage->set(old_storage->length(), value); // Set the new property value and do the map transition. object->set_properties(new_storage); object->set_map(transition); // Return the stored value. return value; } // Used from ic-.cc. RUNTIME_FUNCTION(MaybeObject*, KeyedStoreIC_Miss) { HandleScope scope(isolate); ASSERT(args.length() == 3); KeyedStoreIC ic(isolate); IC::State state = IC::StateFrom(ic.target(), args[0], args[1]); Code::ExtraICState extra_ic_state = ic.target()->extra_ic_state(); return ic.Store(state, Code::GetStrictMode(extra_ic_state), args.at(0), args.at(1), args.at(2), false); } RUNTIME_FUNCTION(MaybeObject*, KeyedStoreIC_Slow) { NoHandleAllocation na; ASSERT(args.length() == 3); KeyedStoreIC ic(isolate); Code::ExtraICState extra_ic_state = ic.target()->extra_ic_state(); Handle object = args.at(0); Handle key = args.at(1); Handle value = args.at(2); StrictModeFlag strict_mode = Code::GetStrictMode(extra_ic_state); return Runtime::SetObjectProperty(isolate, object, key, value, NONE, strict_mode); } RUNTIME_FUNCTION(MaybeObject*, KeyedStoreIC_MissForceGeneric) { HandleScope scope(isolate); ASSERT(args.length() == 3); KeyedStoreIC ic(isolate); IC::State state = IC::StateFrom(ic.target(), args[0], args[1]); Code::ExtraICState extra_ic_state = ic.target()->extra_ic_state(); return ic.Store(state, Code::GetStrictMode(extra_ic_state), args.at(0), args.at(1), args.at(2), true); } void UnaryOpIC::patch(Code* code) { set_target(code); } const char* UnaryOpIC::GetName(TypeInfo type_info) { switch (type_info) { case UNINITIALIZED: return "Uninitialized"; case SMI: return "Smi"; case HEAP_NUMBER: return "HeapNumbers"; case GENERIC: return "Generic"; default: return "Invalid"; } } UnaryOpIC::State UnaryOpIC::ToState(TypeInfo type_info) { switch (type_info) { case UNINITIALIZED: return ::v8::internal::UNINITIALIZED; case SMI: case HEAP_NUMBER: return MONOMORPHIC; case GENERIC: return MEGAMORPHIC; } UNREACHABLE(); return ::v8::internal::UNINITIALIZED; } UnaryOpIC::TypeInfo UnaryOpIC::GetTypeInfo(Handle operand) { ::v8::internal::TypeInfo operand_type = ::v8::internal::TypeInfo::TypeFromValue(operand); if (operand_type.IsSmi()) { return SMI; } else if (operand_type.IsNumber()) { return HEAP_NUMBER; } else { return GENERIC; } } UnaryOpIC::TypeInfo UnaryOpIC::ComputeNewType( UnaryOpIC::TypeInfo current_type, UnaryOpIC::TypeInfo previous_type) { switch (previous_type) { case UnaryOpIC::UNINITIALIZED: return current_type; case UnaryOpIC::SMI: return (current_type == UnaryOpIC::GENERIC) ? UnaryOpIC::GENERIC : UnaryOpIC::HEAP_NUMBER; case UnaryOpIC::HEAP_NUMBER: return UnaryOpIC::GENERIC; case UnaryOpIC::GENERIC: // We should never do patching if we are in GENERIC state. UNREACHABLE(); return UnaryOpIC::GENERIC; } UNREACHABLE(); return UnaryOpIC::GENERIC; } void BinaryOpIC::patch(Code* code) { set_target(code); } const char* BinaryOpIC::GetName(TypeInfo type_info) { switch (type_info) { case UNINITIALIZED: return "Uninitialized"; case SMI: return "SMI"; case INT32: return "Int32s"; case HEAP_NUMBER: return "HeapNumbers"; case ODDBALL: return "Oddball"; case BOTH_STRING: return "BothStrings"; case STRING: return "Strings"; case GENERIC: return "Generic"; default: return "Invalid"; } } BinaryOpIC::State BinaryOpIC::ToState(TypeInfo type_info) { switch (type_info) { case UNINITIALIZED: return ::v8::internal::UNINITIALIZED; case SMI: case INT32: case HEAP_NUMBER: case ODDBALL: case BOTH_STRING: case STRING: return MONOMORPHIC; case GENERIC: return MEGAMORPHIC; } UNREACHABLE(); return ::v8::internal::UNINITIALIZED; } BinaryOpIC::TypeInfo BinaryOpIC::JoinTypes(BinaryOpIC::TypeInfo x, BinaryOpIC::TypeInfo y) { if (x == UNINITIALIZED) return y; if (y == UNINITIALIZED) return x; if (x == y) return x; if (x == BOTH_STRING && y == STRING) return STRING; if (x == STRING && y == BOTH_STRING) return STRING; if (x == STRING || x == BOTH_STRING || y == STRING || y == BOTH_STRING) { return GENERIC; } if (x > y) return x; return y; } BinaryOpIC::TypeInfo BinaryOpIC::GetTypeInfo(Handle left, Handle right) { ::v8::internal::TypeInfo left_type = ::v8::internal::TypeInfo::TypeFromValue(left); ::v8::internal::TypeInfo right_type = ::v8::internal::TypeInfo::TypeFromValue(right); if (left_type.IsSmi() && right_type.IsSmi()) { return SMI; } if (left_type.IsInteger32() && right_type.IsInteger32()) { // Platforms with 32-bit Smis have no distinct INT32 type. if (kSmiValueSize == 32) return SMI; return INT32; } if (left_type.IsNumber() && right_type.IsNumber()) { return HEAP_NUMBER; } // Patching for fast string ADD makes sense even if only one of the // arguments is a string. if (left_type.IsString()) { return right_type.IsString() ? BOTH_STRING : STRING; } else if (right_type.IsString()) { return STRING; } // Check for oddball objects. if (left->IsUndefined() && right->IsNumber()) return ODDBALL; if (left->IsNumber() && right->IsUndefined()) return ODDBALL; return GENERIC; } RUNTIME_FUNCTION(MaybeObject*, UnaryOp_Patch) { ASSERT(args.length() == 4); HandleScope scope(isolate); Handle operand = args.at(0); Token::Value op = static_cast(args.smi_at(1)); UnaryOverwriteMode mode = static_cast(args.smi_at(2)); UnaryOpIC::TypeInfo previous_type = static_cast(args.smi_at(3)); UnaryOpIC::TypeInfo type = UnaryOpIC::GetTypeInfo(operand); type = UnaryOpIC::ComputeNewType(type, previous_type); UnaryOpStub stub(op, mode, type); Handle code = stub.GetCode(); if (!code.is_null()) { if (FLAG_trace_ic) { PrintF("[UnaryOpIC (%s->%s)#%s]\n", UnaryOpIC::GetName(previous_type), UnaryOpIC::GetName(type), Token::Name(op)); } UnaryOpIC ic(isolate); ic.patch(*code); } Handle builtins = Handle( isolate->thread_local_top()->context_->builtins(), isolate); Object* builtin = NULL; // Initialization calms down the compiler. switch (op) { case Token::SUB: builtin = builtins->javascript_builtin(Builtins::UNARY_MINUS); break; case Token::BIT_NOT: builtin = builtins->javascript_builtin(Builtins::BIT_NOT); break; default: UNREACHABLE(); } Handle builtin_function(JSFunction::cast(builtin), isolate); bool caught_exception; Handle result = Execution::Call(builtin_function, operand, 0, NULL, &caught_exception); if (caught_exception) { return Failure::Exception(); } return *result; } RUNTIME_FUNCTION(MaybeObject*, BinaryOp_Patch) { ASSERT(args.length() == 5); HandleScope scope(isolate); Handle left = args.at(0); Handle right = args.at(1); int key = args.smi_at(2); Token::Value op = static_cast(args.smi_at(3)); BinaryOpIC::TypeInfo previous_type = static_cast(args.smi_at(4)); BinaryOpIC::TypeInfo type = BinaryOpIC::GetTypeInfo(left, right); type = BinaryOpIC::JoinTypes(type, previous_type); BinaryOpIC::TypeInfo result_type = BinaryOpIC::UNINITIALIZED; if ((type == BinaryOpIC::STRING || type == BinaryOpIC::BOTH_STRING) && op != Token::ADD) { type = BinaryOpIC::GENERIC; } if (type == BinaryOpIC::SMI && previous_type == BinaryOpIC::SMI) { if (op == Token::DIV || op == Token::MUL || op == Token::SHR || kSmiValueSize == 32) { // Arithmetic on two Smi inputs has yielded a heap number. // That is the only way to get here from the Smi stub. // With 32-bit Smis, all overflows give heap numbers, but with // 31-bit Smis, most operations overflow to int32 results. result_type = BinaryOpIC::HEAP_NUMBER; } else { // Other operations on SMIs that overflow yield int32s. result_type = BinaryOpIC::INT32; } } if (type == BinaryOpIC::INT32 && previous_type == BinaryOpIC::INT32) { // We must be here because an operation on two INT32 types overflowed. result_type = BinaryOpIC::HEAP_NUMBER; } BinaryOpStub stub(key, type, result_type); Handle code = stub.GetCode(); if (!code.is_null()) { if (FLAG_trace_ic) { PrintF("[BinaryOpIC (%s->(%s->%s))#%s]\n", BinaryOpIC::GetName(previous_type), BinaryOpIC::GetName(type), BinaryOpIC::GetName(result_type), Token::Name(op)); } BinaryOpIC ic(isolate); ic.patch(*code); // Activate inlined smi code. if (previous_type == BinaryOpIC::UNINITIALIZED) { PatchInlinedSmiCode(ic.address(), ENABLE_INLINED_SMI_CHECK); } } Handle builtins = Handle( isolate->thread_local_top()->context_->builtins(), isolate); Object* builtin = NULL; // Initialization calms down the compiler. switch (op) { case Token::ADD: builtin = builtins->javascript_builtin(Builtins::ADD); break; case Token::SUB: builtin = builtins->javascript_builtin(Builtins::SUB); break; case Token::MUL: builtin = builtins->javascript_builtin(Builtins::MUL); break; case Token::DIV: builtin = builtins->javascript_builtin(Builtins::DIV); break; case Token::MOD: builtin = builtins->javascript_builtin(Builtins::MOD); break; case Token::BIT_AND: builtin = builtins->javascript_builtin(Builtins::BIT_AND); break; case Token::BIT_OR: builtin = builtins->javascript_builtin(Builtins::BIT_OR); break; case Token::BIT_XOR: builtin = builtins->javascript_builtin(Builtins::BIT_XOR); break; case Token::SHR: builtin = builtins->javascript_builtin(Builtins::SHR); break; case Token::SAR: builtin = builtins->javascript_builtin(Builtins::SAR); break; case Token::SHL: builtin = builtins->javascript_builtin(Builtins::SHL); break; default: UNREACHABLE(); } Handle builtin_function(JSFunction::cast(builtin), isolate); bool caught_exception; Handle builtin_args[] = { right }; Handle result = Execution::Call(builtin_function, left, ARRAY_SIZE(builtin_args), builtin_args, &caught_exception); if (caught_exception) { return Failure::Exception(); } return *result; } Code* CompareIC::GetRawUninitialized(Token::Value op) { ICCompareStub stub(op, UNINITIALIZED); Code* code = NULL; CHECK(stub.FindCodeInCache(&code)); return code; } Handle CompareIC::GetUninitialized(Token::Value op) { ICCompareStub stub(op, UNINITIALIZED); return stub.GetCode(); } CompareIC::State CompareIC::ComputeState(Code* target) { int key = target->major_key(); if (key == CodeStub::Compare) return GENERIC; ASSERT(key == CodeStub::CompareIC); return static_cast(target->compare_state()); } Token::Value CompareIC::ComputeOperation(Code* target) { ASSERT(target->major_key() == CodeStub::CompareIC); return static_cast( target->compare_operation() + Token::EQ); } const char* CompareIC::GetStateName(State state) { switch (state) { case UNINITIALIZED: return "UNINITIALIZED"; case SMIS: return "SMIS"; case HEAP_NUMBERS: return "HEAP_NUMBERS"; case OBJECTS: return "OBJECTS"; case KNOWN_OBJECTS: return "KNOWN_OBJECTS"; case SYMBOLS: return "SYMBOLS"; case STRINGS: return "STRINGS"; case GENERIC: return "GENERIC"; default: UNREACHABLE(); return NULL; } } CompareIC::State CompareIC::TargetState(State state, bool has_inlined_smi_code, Handle x, Handle y) { switch (state) { case UNINITIALIZED: if (x->IsSmi() && y->IsSmi()) return SMIS; if (x->IsNumber() && y->IsNumber()) return HEAP_NUMBERS; if (Token::IsOrderedRelationalCompareOp(op_)) { // Ordered comparisons treat undefined as NaN, so the // HEAP_NUMBER stub will do the right thing. if ((x->IsNumber() && y->IsUndefined()) || (y->IsNumber() && x->IsUndefined())) { return HEAP_NUMBERS; } } if (x->IsSymbol() && y->IsSymbol()) { // We compare symbols as strings if we need to determine // the order in a non-equality compare. return Token::IsEqualityOp(op_) ? SYMBOLS : STRINGS; } if (x->IsString() && y->IsString()) return STRINGS; if (!Token::IsEqualityOp(op_)) return GENERIC; if (x->IsJSObject() && y->IsJSObject()) { if (Handle::cast(x)->map() == Handle::cast(y)->map() && Token::IsEqualityOp(op_)) { return KNOWN_OBJECTS; } else { return OBJECTS; } } return GENERIC; case SMIS: return has_inlined_smi_code && x->IsNumber() && y->IsNumber() ? HEAP_NUMBERS : GENERIC; case SYMBOLS: ASSERT(Token::IsEqualityOp(op_)); return x->IsString() && y->IsString() ? STRINGS : GENERIC; case HEAP_NUMBERS: case STRINGS: case OBJECTS: case KNOWN_OBJECTS: case GENERIC: return GENERIC; } UNREACHABLE(); return GENERIC; } // Used from ic_.cc. RUNTIME_FUNCTION(Code*, CompareIC_Miss) { NoHandleAllocation na; ASSERT(args.length() == 3); CompareIC ic(isolate, static_cast(args.smi_at(2))); ic.UpdateCaches(args.at(0), args.at(1)); return ic.target(); } RUNTIME_FUNCTION(MaybeObject*, ToBoolean_Patch) { ASSERT(args.length() == 3); HandleScope scope(isolate); Handle object = args.at(0); Register tos = Register::from_code(args.smi_at(1)); ToBooleanStub::Types old_types(args.smi_at(2)); ToBooleanStub::Types new_types(old_types); bool to_boolean_value = new_types.Record(object); old_types.TraceTransition(new_types); ToBooleanStub stub(tos, new_types); Handle code = stub.GetCode(); ToBooleanIC ic(isolate); ic.patch(*code); return Smi::FromInt(to_boolean_value ? 1 : 0); } void ToBooleanIC::patch(Code* code) { set_target(code); } static const Address IC_utilities[] = { #define ADDR(name) FUNCTION_ADDR(name), IC_UTIL_LIST(ADDR) NULL #undef ADDR }; Address IC::AddressFromUtilityId(IC::UtilityId id) { return IC_utilities[id]; } } } // namespace v8::internal