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// 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<Object> 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<Address*>(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<Address*>(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<SharedFunctionInfo> 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> object,
Handle<Object> key) {
HandleScope scope(isolate());
Handle<Object> args[2] = { key, object };
Handle<Object> error = isolate()->factory()->NewTypeError(
type, HandleVector(args, 2));
return isolate()->Throw(*error);
}
Failure* IC::ReferenceError(const char* type, Handle<String> name) {
HandleScope scope(isolate());
Handle<Object> 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;
}
Isolate* isolate = target->GetHeap()->isolate();
Code* host = 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->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) {
ASSERT(target->major_key() == CodeStub::CompareIC);
CompareIC::State handler_state;
Token::Value op;
ICCompareStub::DecodeMinorKey(target->stub_info(), NULL, NULL,
&handler_state, &op);
// Only clear CompareICs that can retain objects.
if (handler_state != KNOWN_OBJECTS) return;
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> object,
Handle<String> 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<JSObject> holder(lookup->holder());
if (HasInterceptorGetter(*holder)) {
return;
}
holder->LocalLookupRealNamedProperty(*name, lookup);
if (lookup->IsFound()) {
ASSERT(!lookup->IsInterceptor());
return;
}
Handle<Object> proto(holder->GetPrototype());
if (proto->IsNull()) {
ASSERT(!lookup->IsFound());
return;
}
object = proto;
}
}
Handle<Object> CallICBase::TryCallAsFunction(Handle<Object> object) {
Handle<Object> 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<Object> callee,
Handle<Object> object) {
while (callee->IsJSFunctionProxy()) {
callee = Handle<Object>(JSFunctionProxy::cast(*callee)->call_trap());
}
if (callee->IsJSFunction()) {
Handle<JSFunction> function = Handle<JSFunction>::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> object,
Handle<String> 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<Object> 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<Object> 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<JSFunction> function = Handle<JSFunction>::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> 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<Code> CallICBase::ComputeMonomorphicStub(LookupResult* lookup,
State state,
Code::ExtraICState extra_state,
Handle<Object> object,
Handle<String> name) {
int argc = target()->arguments_count();
Handle<JSObject> holder(lookup->holder());
switch (lookup->type()) {
case FIELD: {
PropertyIndex 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<JSFunction> 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<Code>::null();
Handle<JSObject> receiver = Handle<JSObject>::cast(object);
if (holder->IsGlobalObject()) {
Handle<GlobalObject> global = Handle<GlobalObject>::cast(holder);
Handle<JSGlobalPropertyCell> cell(global->GetPropertyCell(lookup));
if (!cell->value()->IsJSFunction()) return Handle<Code>::null();
Handle<JSFunction> 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<Code>::null();
return isolate()->stub_cache()->ComputeCallNormal(
argc, kind_, extra_state);
}
break;
}
case INTERCEPTOR:
ASSERT(HasInterceptorGetter(*holder));
return isolate()->stub_cache()->ComputeCallInterceptor(
argc, kind_, extra_state, name, object, holder);
default:
return Handle<Code>::null();
}
}
void CallICBase::UpdateCaches(LookupResult* lookup,
State state,
Code::ExtraICState extra_ic_state,
Handle<Object> object,
Handle<String> 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> 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<JSObject> cache_object = object->IsJSObject()
? Handle<JSObject>::cast(object)
: Handle<JSObject>(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> object,
Handle<Object> key) {
if (key->IsSymbol()) {
return CallICBase::LoadFunction(state,
Code::kNoExtraICState,
object,
Handle<String>::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> map =
isolate()->factory()->non_strict_arguments_elements_map();
if (object->IsJSObject() &&
Handle<JSObject>::cast(object)->elements()->map() == *map) {
Handle<Code> 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> code = isolate()->stub_cache()->ComputeCallMegamorphic(
argc, Code::KEYED_CALL_IC, Code::kNoExtraICState);
set_target(*code);
TRACE_IC("KeyedCallIC", key, state, target());
}
}
Handle<Object> 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> object,
Handle<String> 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<Code> 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<Object> string = object->IsJSValue()
? Handle<Object>(Handle<JSValue>::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<Code> 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<JSFunction>::cast(object)->should_have_prototype()) {
Handle<Code> 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<Object> 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> object,
Handle<String> 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<JSObject> receiver = Handle<JSObject>::cast(object);
if (HasNormalObjectsInPrototypeChain(isolate(), lookup, *object)) return;
// Compute the code stub for this load.
Handle<Code> 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<JSObject> holder(lookup->holder());
switch (lookup->type()) {
case FIELD:
code = isolate()->stub_cache()->ComputeLoadField(
name, receiver, holder, lookup->GetFieldIndex());
break;
case CONSTANT_FUNCTION: {
Handle<JSFunction> constant(lookup->GetConstantFunction());
code = isolate()->stub_cache()->ComputeLoadConstant(
name, receiver, holder, constant);
break;
}
case NORMAL:
if (holder->IsGlobalObject()) {
Handle<GlobalObject> global = Handle<GlobalObject>::cast(holder);
Handle<JSGlobalPropertyCell> 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: {
Handle<Object> callback(lookup->GetCallbackObject());
if (callback->IsAccessorInfo()) {
Handle<AccessorInfo> info = Handle<AccessorInfo>::cast(callback);
if (v8::ToCData<Address>(info->getter()) == 0) return;
if (!info->IsCompatibleReceiver(*receiver)) return;
code = isolate()->stub_cache()->ComputeLoadCallback(
name, receiver, holder, info);
} else if (callback->IsAccessorPair()) {
Handle<Object> getter(Handle<AccessorPair>::cast(callback)->getter());
if (!getter->IsJSFunction()) return;
if (holder->IsGlobalObject()) return;
if (!holder->HasFastProperties()) return;
code = isolate()->stub_cache()->ComputeLoadViaGetter(
name, receiver, holder, Handle<JSFunction>::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<Code> 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<Code> 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<Map> receiver_map = receiver_maps->at(i);
Handle<Code> cached_stub = ComputeMonomorphicStubWithoutMapCheck(
receiver_map, strict_mode, growth_mode);
handler_ics.Add(cached_stub);
}
KeyedLoadStubCompiler compiler(isolate());
Handle<Code> 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<Object> TryConvertKey(Handle<Object> 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<HeapNumber>::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>(Smi::FromInt(int_value));
}
}
} else if (key->IsUndefined()) {
key = isolate->factory()->undefined_symbol();
}
return key;
}
MaybeObject* KeyedLoadIC::Load(State state,
Handle<Object> object,
Handle<Object> 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<String> name = Handle<String>::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> string = Handle<String>::cast(object);
Handle<Code> 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<JSArray> array = Handle<JSArray>::cast(object);
Handle<Code> 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<JSFunction>::cast(object)->should_have_prototype()) {
Handle<JSFunction> function = Handle<JSFunction>::cast(object);
Handle<Code> 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<Object> 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<Code> stub = generic_stub();
if (!force_generic_stub) {
if (object->IsString() && key->IsNumber()) {
if (state == UNINITIALIZED) {
stub = string_stub();
}
} else if (object->IsJSObject()) {
Handle<JSObject> receiver = Handle<JSObject>::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> object,
Handle<String> name) {
// Bail out if we didn't find a result.
if (!lookup->IsProperty() || !lookup->IsCacheable()) return;
if (!object->IsJSObject()) return;
Handle<JSObject> receiver = Handle<JSObject>::cast(object);
if (HasNormalObjectsInPrototypeChain(isolate(), lookup, *object)) return;
// Compute the code stub for this load.
Handle<Code> 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<JSObject> holder(lookup->holder());
switch (lookup->type()) {
case FIELD:
code = isolate()->stub_cache()->ComputeKeyedLoadField(
name, receiver, holder, lookup->GetFieldIndex());
break;
case CONSTANT_FUNCTION: {
Handle<JSFunction> constant(lookup->GetConstantFunction());
code = isolate()->stub_cache()->ComputeKeyedLoadConstant(
name, receiver, holder, constant);
break;
}
case CALLBACKS: {
Handle<Object> callback_object(lookup->GetCallbackObject());
if (!callback_object->IsAccessorInfo()) return;
Handle<AccessorInfo> callback =
Handle<AccessorInfo>::cast(callback_object);
if (v8::ToCData<Address>(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<JSObject> receiver,
Handle<String> 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> object,
Handle<String> name,
Handle<Object> 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<JSObject> receiver = Handle<JSObject>::cast(object);
// Check if the given name is an array index.
uint32_t index;
if (name->AsArrayIndex(&index)) {
Handle<Object> 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<JSArray>::cast(receiver)->AllowsSetElementsLength() &&
receiver->HasFastProperties()) {
#ifdef DEBUG
if (FLAG_trace_ic) PrintF("[StoreIC : +#length /array]\n");
#endif
Handle<Code> 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<Code> 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<JSObject> receiver,
Handle<String> name,
Handle<Object> 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<JSObject> holder(lookup->holder());
Handle<Code> code;
switch (type) {
case FIELD:
code = isolate()->stub_cache()->ComputeStoreField(
name, receiver, lookup->GetFieldIndex().field_index(),
Handle<Map>::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<GlobalObject> global = Handle<GlobalObject>::cast(receiver);
Handle<JSGlobalPropertyCell> 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<Object> callback(lookup->GetCallbackObject());
if (callback->IsAccessorInfo()) {
Handle<AccessorInfo> info = Handle<AccessorInfo>::cast(callback);
if (v8::ToCData<Address>(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<Object> setter(Handle<AccessorPair>::cast(callback)->setter());
if (!setter->IsJSFunction()) return;
if (holder->IsGlobalObject()) return;
if (!holder->HasFastProperties()) return;
code = isolate()->stub_cache()->ComputeStoreViaSetter(
name, receiver, holder, Handle<JSFunction>::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<Map> 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<Map> 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<Code> 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<Map>(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> object(info->target_object());
ASSERT(object->IsMap());
AddOneReceiverMapIfMissing(result, Handle<Map>::cast(object));
}
}
}
}
Handle<Code> KeyedIC::ComputeStub(Handle<JSObject> receiver,
StubKind stub_kind,
StrictModeFlag strict_mode,
Handle<Code> 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<Map> receiver_map(receiver->map());
Handle<Map> 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<Code>(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<Map> 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<PolymorphicCodeCache> 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<Object> probe = cache->Lookup(&target_receiver_maps, flags);
if (probe->IsCode()) return Handle<Code>::cast(probe);
Handle<Code> stub =
ComputePolymorphicStub(&target_receiver_maps, strict_mode, grow_mode);
PolymorphicCodeCache::Update(cache, &target_receiver_maps, flags, stub);
return stub;
}
Handle<Code> KeyedIC::ComputeMonomorphicStubWithoutMapCheck(
Handle<Map> 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<Code> KeyedIC::ComputeMonomorphicStub(Handle<Map> receiver_map,
StubKind stub_kind,
StrictModeFlag strict_mode,
Handle<Code> 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<Map> KeyedIC::ComputeTransitionedMap(Handle<JSObject> 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<Map>::null();
}
Handle<Code> KeyedStoreIC::GetElementStubWithoutMapCheck(
bool is_js_array,
ElementsKind elements_kind,
KeyedAccessGrowMode grow_mode) {
return KeyedStoreElementStub(is_js_array, elements_kind, grow_mode).GetCode();
}
Handle<Code> 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<Map> receiver_map(receiver_maps->at(i));
Handle<Code> cached_stub;
Handle<Map> 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> 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<JSObject> receiver,
Handle<Object> key,
Handle<Object> 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> object,
Handle<Object> key,
Handle<Object> 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<String> name = Handle<String>::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<JSObject> receiver = Handle<JSObject>::cast(object);
// Check if the given name is an array index.
uint32_t index;
if (name->AsArrayIndex(&index)) {
Handle<Object> 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<Code> stub = (strict_mode == kStrictMode)
? generic_stub_strict()
: generic_stub();
if (object->IsJSObject()) {
Handle<JSObject> receiver = Handle<JSObject>::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<JSObject> receiver,
Handle<String> name,
Handle<Object> 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> code;
switch (type) {
case FIELD:
code = isolate()->stub_cache()->ComputeKeyedStoreField(
name, receiver, lookup->GetFieldIndex().field_index(),
Handle<Map>::null(), strict_mode);
break;
case TRANSITION: {
Handle<Map> 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-<arch>.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<Object>(0),
args.at<String>(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<JSFunction> function(raw_function);
JSFunction::CompileLazy(function, CLEAR_EXCEPTION);
return *function;
}
// Used from ic-<arch>.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<Object>(0), args.at<Object>(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<JSFunction> function(raw_function);
JSFunction::CompileLazy(function, CLEAR_EXCEPTION);
return *function;
}
// Used from ic-<arch>.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<Object>(0), args.at<String>(1));
}
// Used from ic-<arch>.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<Object>(0), args.at<Object>(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<Object>(0), args.at<Object>(1), true);
}
// Used from ic-<arch>.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<Object>(0),
args.at<String>(1),
args.at<Object>(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-<arch>.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<Object>(0),
args.at<Object>(1),
args.at<Object>(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> object = args.at<Object>(0);
Handle<Object> key = args.at<Object>(1);
Handle<Object> value = args.at<Object>(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<Object>(0),
args.at<Object>(1),
args.at<Object>(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<Object> 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 "Int32";
case HEAP_NUMBER: return "HeapNumber";
case ODDBALL: return "Oddball";
case STRING: return "String";
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 STRING:
return MONOMORPHIC;
case GENERIC:
return MEGAMORPHIC;
}
UNREACHABLE();
return ::v8::internal::UNINITIALIZED;
}
RUNTIME_FUNCTION(MaybeObject*, UnaryOp_Patch) {
ASSERT(args.length() == 4);
HandleScope scope(isolate);
Handle<Object> operand = args.at<Object>(0);
Token::Value op = static_cast<Token::Value>(args.smi_at(1));
UnaryOverwriteMode mode = static_cast<UnaryOverwriteMode>(args.smi_at(2));
UnaryOpIC::TypeInfo previous_type =
static_cast<UnaryOpIC::TypeInfo>(args.smi_at(3));
UnaryOpIC::TypeInfo type = UnaryOpIC::GetTypeInfo(operand);
type = UnaryOpIC::ComputeNewType(type, previous_type);
UnaryOpStub stub(op, mode, type);
Handle<Code> 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<JSBuiltinsObject> builtins = Handle<JSBuiltinsObject>(
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<JSFunction> builtin_function(JSFunction::cast(builtin), isolate);
bool caught_exception;
Handle<Object> result = Execution::Call(builtin_function, operand, 0, NULL,
&caught_exception);
if (caught_exception) {
return Failure::Exception();
}
return *result;
}
static BinaryOpIC::TypeInfo TypeInfoFromValue(Handle<Object> value,
Token::Value op) {
::v8::internal::TypeInfo type =
::v8::internal::TypeInfo::TypeFromValue(value);
if (type.IsSmi()) return BinaryOpIC::SMI;
if (type.IsInteger32()) {
if (kSmiValueSize == 32) return BinaryOpIC::SMI;
return BinaryOpIC::INT32;
}
if (type.IsNumber()) return BinaryOpIC::HEAP_NUMBER;
if (type.IsString()) return BinaryOpIC::STRING;
if (value->IsUndefined()) {
if (op == Token::BIT_AND ||
op == Token::BIT_OR ||
op == Token::BIT_XOR ||
op == Token::SAR ||
op == Token::SHL ||
op == Token::SHR) {
if (kSmiValueSize == 32) return BinaryOpIC::SMI;
return BinaryOpIC::INT32;
}
return BinaryOpIC::ODDBALL;
}
return BinaryOpIC::GENERIC;
}
static BinaryOpIC::TypeInfo InputState(BinaryOpIC::TypeInfo old_type,
Handle<Object> value,
Token::Value op) {
BinaryOpIC::TypeInfo new_type = TypeInfoFromValue(value, op);
if (old_type == BinaryOpIC::STRING) {
if (new_type == BinaryOpIC::STRING) return new_type;
return BinaryOpIC::GENERIC;
}
return Max(old_type, new_type);
}
RUNTIME_FUNCTION(MaybeObject*, BinaryOp_Patch) {
ASSERT(args.length() == 3);
HandleScope scope(isolate);
Handle<Object> left = args.at<Object>(0);
Handle<Object> right = args.at<Object>(1);
int key = args.smi_at(2);
Token::Value op = BinaryOpStub::decode_op_from_minor_key(key);
BinaryOpIC::TypeInfo previous_left, previous_right, unused_previous_result;
BinaryOpStub::decode_types_from_minor_key(
key, &previous_left, &previous_right, &unused_previous_result);
BinaryOpIC::TypeInfo new_left = InputState(previous_left, left, op);
BinaryOpIC::TypeInfo new_right = InputState(previous_right, right, op);
BinaryOpIC::TypeInfo result_type = BinaryOpIC::UNINITIALIZED;
// STRING is only used for ADD operations.
if ((new_left == BinaryOpIC::STRING || new_right == BinaryOpIC::STRING) &&
op != Token::ADD) {
new_left = new_right = BinaryOpIC::GENERIC;
}
BinaryOpIC::TypeInfo new_overall = Max(new_left, new_right);
BinaryOpIC::TypeInfo previous_overall = Max(previous_left, previous_right);
if (new_overall == BinaryOpIC::SMI && previous_overall == 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 (new_overall == BinaryOpIC::INT32 &&
previous_overall == BinaryOpIC::INT32) {
if (new_left == previous_left && new_right == previous_right) {
result_type = BinaryOpIC::HEAP_NUMBER;
}
}
BinaryOpStub stub(key, new_left, new_right, result_type);
Handle<Code> code = stub.GetCode();
if (!code.is_null()) {
#ifdef DEBUG
if (FLAG_trace_ic) {
PrintF("[BinaryOpIC in ");
JavaScriptFrame::PrintTop(stdout, false, true);
PrintF(" ((%s+%s)->((%s+%s)->%s))#%s @ %p]\n",
BinaryOpIC::GetName(previous_left),
BinaryOpIC::GetName(previous_right),
BinaryOpIC::GetName(new_left),
BinaryOpIC::GetName(new_right),
BinaryOpIC::GetName(result_type),
Token::Name(op),
static_cast<void*>(*code));
}
#endif
BinaryOpIC ic(isolate);
ic.patch(*code);
// Activate inlined smi code.
if (previous_overall == BinaryOpIC::UNINITIALIZED) {
PatchInlinedSmiCode(ic.address(), ENABLE_INLINED_SMI_CHECK);
}
}
Handle<JSBuiltinsObject> builtins = Handle<JSBuiltinsObject>(
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<JSFunction> builtin_function(JSFunction::cast(builtin), isolate);
bool caught_exception;
Handle<Object> builtin_args[] = { right };
Handle<Object> 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, UNINITIALIZED, UNINITIALIZED);
Code* code = NULL;
CHECK(stub.FindCodeInCache(&code, Isolate::Current()));
return code;
}
Handle<Code> CompareIC::GetUninitialized(Token::Value op) {
ICCompareStub stub(op, UNINITIALIZED, UNINITIALIZED, UNINITIALIZED);
return stub.GetCode();
}
const char* CompareIC::GetStateName(State state) {
switch (state) {
case UNINITIALIZED: return "UNINITIALIZED";
case SMI: return "SMI";
case HEAP_NUMBER: return "HEAP_NUMBER";
case OBJECT: return "OBJECTS";
case KNOWN_OBJECTS: return "KNOWN_OBJECTS";
case SYMBOL: return "SYMBOL";
case STRING: return "STRING";
case GENERIC: return "GENERIC";
default:
UNREACHABLE();
return NULL;
}
}
static CompareIC::State InputState(CompareIC::State old_state,
Handle<Object> value) {
switch (old_state) {
case CompareIC::UNINITIALIZED:
if (value->IsSmi()) return CompareIC::SMI;
if (value->IsHeapNumber()) return CompareIC::HEAP_NUMBER;
if (value->IsSymbol()) return CompareIC::SYMBOL;
if (value->IsString()) return CompareIC::STRING;
if (value->IsJSObject()) return CompareIC::OBJECT;
break;
case CompareIC::SMI:
if (value->IsSmi()) return CompareIC::SMI;
if (value->IsHeapNumber()) return CompareIC::HEAP_NUMBER;
break;
case CompareIC::HEAP_NUMBER:
if (value->IsNumber()) return CompareIC::HEAP_NUMBER;
break;
case CompareIC::SYMBOL:
if (value->IsSymbol()) return CompareIC::SYMBOL;
if (value->IsString()) return CompareIC::STRING;
break;
case CompareIC::STRING:
if (value->IsSymbol() || value->IsString()) return CompareIC::STRING;
break;
case CompareIC::OBJECT:
if (value->IsJSObject()) return CompareIC::OBJECT;
break;
case CompareIC::GENERIC:
break;
case CompareIC::KNOWN_OBJECTS:
UNREACHABLE();
break;
}
return CompareIC::GENERIC;
}
CompareIC::State CompareIC::TargetState(State old_state,
State old_left,
State old_right,
bool has_inlined_smi_code,
Handle<Object> x,
Handle<Object> y) {
switch (old_state) {
case UNINITIALIZED:
if (x->IsSmi() && y->IsSmi()) return SMI;
if (x->IsNumber() && y->IsNumber()) return HEAP_NUMBER;
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_NUMBER;
}
}
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_) ? SYMBOL : STRING;
}
if (x->IsString() && y->IsString()) return STRING;
if (!Token::IsEqualityOp(op_)) return GENERIC;
if (x->IsJSObject() && y->IsJSObject()) {
if (Handle<JSObject>::cast(x)->map() ==
Handle<JSObject>::cast(y)->map() &&
Token::IsEqualityOp(op_)) {
return KNOWN_OBJECTS;
} else {
return OBJECT;
}
}
return GENERIC;
case SMI:
return x->IsNumber() && y->IsNumber()
? HEAP_NUMBER
: GENERIC;
case SYMBOL:
ASSERT(Token::IsEqualityOp(op_));
return x->IsString() && y->IsString() ? STRING : GENERIC;
case HEAP_NUMBER:
if (old_left == SMI && x->IsHeapNumber()) return HEAP_NUMBER;
if (old_right == SMI && y->IsHeapNumber()) return HEAP_NUMBER;
case STRING:
case OBJECT:
case KNOWN_OBJECTS:
case GENERIC:
return GENERIC;
}
UNREACHABLE();
return GENERIC; // Make the compiler happy.
}
void CompareIC::UpdateCaches(Handle<Object> x, Handle<Object> y) {
HandleScope scope;
State previous_left, previous_right, previous_state;
ICCompareStub::DecodeMinorKey(target()->stub_info(), &previous_left,
&previous_right, &previous_state, NULL);
State new_left = InputState(previous_left, x);
State new_right = InputState(previous_right, y);
State state = TargetState(previous_state, previous_left, previous_right,
HasInlinedSmiCode(address()), x, y);
ICCompareStub stub(op_, new_left, new_right, state);
if (state == KNOWN_OBJECTS) {
stub.set_known_map(Handle<Map>(Handle<JSObject>::cast(x)->map()));
}
set_target(*stub.GetCode());
#ifdef DEBUG
if (FLAG_trace_ic) {
PrintF("[CompareIC in ");
JavaScriptFrame::PrintTop(stdout, false, true);
PrintF(" ((%s+%s=%s)->(%s+%s=%s))#%s @ %p]\n",
GetStateName(previous_left),
GetStateName(previous_right),
GetStateName(previous_state),
GetStateName(new_left),
GetStateName(new_right),
GetStateName(state),
Token::Name(op_),
static_cast<void*>(*stub.GetCode()));
}
#endif
// Activate inlined smi code.
if (previous_state == UNINITIALIZED) {
PatchInlinedSmiCode(address(), ENABLE_INLINED_SMI_CHECK);
}
}
// Used from ICCompareStub::GenerateMiss in code-stubs-<arch>.cc.
RUNTIME_FUNCTION(Code*, CompareIC_Miss) {
NoHandleAllocation na;
ASSERT(args.length() == 3);
CompareIC ic(isolate, static_cast<Token::Value>(args.smi_at(2)));
ic.UpdateCaches(args.at<Object>(0), args.at<Object>(1));
return ic.target();
}
RUNTIME_FUNCTION(MaybeObject*, ToBoolean_Patch) {
ASSERT(args.length() == 3);
HandleScope scope(isolate);
Handle<Object> object = args.at<Object>(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> 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
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