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ara-mdk / platform / external / v8 / defc87f8a749eebf54f28ebe54377e366ab8b427 / . / src / ic.cc
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// Copyright 2006-2009 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
static char 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 '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,
const char* extra_info) {
if (FLAG_trace_ic) {
State new_state = StateFrom(new_target,
HEAP->undefined_value(),
HEAP->undefined_value());
PrintF("[%s (%c->%c)%s", type,
TransitionMarkFromState(old_state),
TransitionMarkFromState(new_state),
extra_info);
name->Print();
PrintF("]\n");
}
}
#endif
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() {
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 = pc() - Assembler::kCallTargetAddressOffset;
// 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() : 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);
}
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:
case Code::KEYED_EXTERNAL_ARRAY_LOAD_IC:
return KeyedLoadIC::Clear(address, target);
case Code::STORE_IC: return StoreIC::Clear(address, target);
case Code::KEYED_STORE_IC:
case Code::KEYED_EXTERNAL_ARRAY_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::TYPE_RECORDING_BINARY_OP_IC:
case Code::COMPARE_IC:
// Clearing these is tricky and does not
// make any performance difference.
return;
default: UNREACHABLE();
}
}
void CallICBase::Clear(Address address, Code* target) {
State state = target->ic_state();
if (state == UNINITIALIZED) return;
Code* code =
Isolate::Current()->stub_cache()->FindCallInitialize(
target->arguments_count(),
target->ic_in_loop(),
target->kind());
SetTargetAtAddress(address, code);
}
void KeyedLoadIC::ClearInlinedVersion(Address address) {
// Insert null as the map to check for to make sure the map check fails
// sending control flow to the IC instead of the inlined version.
PatchInlinedLoad(address, HEAP->null_value());
}
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.
ClearInlinedVersion(address);
SetTargetAtAddress(address, initialize_stub());
}
void LoadIC::ClearInlinedVersion(Address address) {
// Reset the map check of the inlined inobject property load (if
// present) to guarantee failure by holding an invalid map (the null
// value). The offset can be patched to anything.
Heap* heap = HEAP;
PatchInlinedLoad(address, heap->null_value(), 0);
PatchInlinedContextualLoad(address,
heap->null_value(),
heap->null_value(),
true);
}
void LoadIC::Clear(Address address, Code* target) {
if (target->ic_state() == UNINITIALIZED) return;
ClearInlinedVersion(address);
SetTargetAtAddress(address, initialize_stub());
}
void StoreIC::ClearInlinedVersion(Address address) {
// Reset the map check of the inlined inobject property store (if
// present) to guarantee failure by holding an invalid map (the null
// value). The offset can be patched to anything.
PatchInlinedStore(address, HEAP->null_value(), 0);
}
void StoreIC::Clear(Address address, Code* target) {
if (target->ic_state() == UNINITIALIZED) return;
ClearInlinedVersion(address);
SetTargetAtAddress(address,
(target->extra_ic_state() == kStrictMode)
? initialize_stub_strict()
: initialize_stub());
}
void KeyedStoreIC::ClearInlinedVersion(Address address) {
// Insert null as the elements map to check for. This will make
// sure that the elements fast-case map check fails so that control
// flows to the IC instead of the inlined version.
PatchInlinedStore(address, HEAP->null_value());
}
void KeyedStoreIC::RestoreInlinedVersion(Address address) {
// Restore the fast-case elements map check so that the inlined
// version can be used again.
PatchInlinedStore(address, HEAP->fixed_array_map());
}
void KeyedStoreIC::Clear(Address address, Code* target) {
if (target->ic_state() == UNINITIALIZED) return;
SetTargetAtAddress(address,
(target->extra_ic_state() == kStrictMode)
? initialize_stub_strict()
: initialize_stub());
}
static bool HasInterceptorGetter(JSObject* object) {
return !object->GetNamedInterceptor()->getter()->IsUndefined();
}
static void LookupForRead(Object* object,
String* name,
LookupResult* lookup) {
AssertNoAllocation no_gc; // pointers must stay valid
// 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->IsFound()
|| (lookup->type() != INTERCEPTOR)
|| !lookup->IsCacheable()) {
return;
}
JSObject* holder = lookup->holder();
if (HasInterceptorGetter(holder)) {
return;
}
holder->LocalLookupRealNamedProperty(name, lookup);
if (lookup->IsProperty()) {
ASSERT(lookup->type() != INTERCEPTOR);
return;
}
Object* proto = holder->GetPrototype();
if (proto->IsNull()) {
lookup->NotFound();
return;
}
object = proto;
}
}
Object* CallICBase::TryCallAsFunction(Object* object) {
HandleScope scope(isolate());
Handle<Object> target(object, isolate());
Handle<Object> delegate = Execution::GetFunctionDelegate(target);
if (delegate->IsJSFunction()) {
// 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 = this->target()->arguments_count();
StackFrameLocator locator;
JavaScriptFrame* frame = locator.FindJavaScriptFrame(0);
int index = frame->ComputeExpressionsCount() - (argc + 1);
frame->SetExpression(index, *target);
}
return *delegate;
}
void CallICBase::ReceiverToObjectIfRequired(Handle<Object> callee,
Handle<Object> object) {
if (callee->IsJSFunction()) {
Handle<JSFunction> function = Handle<JSFunction>::cast(callee);
if (function->shared()->strict_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)) {
Object* result;
{ MaybeObject* maybe_result = object->GetElement(index);
if (!maybe_result->ToObject(&result)) return maybe_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;
LookupForRead(*object, *name, &lookup);
if (!lookup.IsProperty()) {
// If the object does not have the requested property, check which
// exception we need to throw.
if (IsContextual(object)) {
return ReferenceError("not_defined", name);
}
return 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;
Object* result;
{ MaybeObject* maybe_result =
object->GetProperty(*object, &lookup, *name, &attr);
if (!maybe_result->ToObject(&result)) return maybe_result;
}
if (lookup.type() == INTERCEPTOR) {
// If the object does not have the requested property, check which
// exception we need to throw.
if (attr == ABSENT) {
if (IsContextual(object)) {
return ReferenceError("not_defined", name);
}
return TypeError("undefined_method", object, name);
}
}
ASSERT(!result->IsTheHole());
HandleScope scope(isolate());
// Wrap result in a handle because ReceiverToObjectIfRequired may allocate
// new object and cause GC.
Handle<Object> result_handle(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_handle, object);
if (result_handle->IsJSFunction()) {
#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.
Handle<JSFunction> function(JSFunction::cast(*result_handle), isolate());
debug->HandleStepIn(function, object, fp(), false);
return *function;
}
#endif
return *result_handle;
}
// Try to find a suitable function delegate for the object at hand.
result_handle = Handle<Object>(TryCallAsFunction(*result_handle));
if (result_handle->IsJSFunction()) return *result_handle;
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 (*extra_ic_state == DEFAULT_STRING_STUB &&
argc >= 1 && args[1]->IsNumber()) {
double index;
if (args[1]->IsSmi()) {
index = Smi::cast(args[1])->value();
} else {
ASSERT(args[1]->IsHeapNumber());
index = DoubleToInteger(HeapNumber::cast(args[1])->value());
}
if (index < 0 || index >= string->length()) {
*extra_ic_state = STRING_INDEX_OUT_OF_BOUNDS;
return true;
}
}
}
break;
default:
return false;
}
return false;
}
MaybeObject* CallICBase::ComputeMonomorphicStub(
LookupResult* lookup,
State state,
Code::ExtraICState extra_ic_state,
Handle<Object> object,
Handle<String> name) {
int argc = target()->arguments_count();
InLoopFlag in_loop = target()->ic_in_loop();
MaybeObject* maybe_code = NULL;
switch (lookup->type()) {
case FIELD: {
int index = lookup->GetFieldIndex();
maybe_code = isolate()->stub_cache()->ComputeCallField(argc,
in_loop,
kind_,
*name,
*object,
lookup->holder(),
index);
break;
}
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.
JSFunction* function = lookup->GetConstantFunction();
maybe_code =
isolate()->stub_cache()->ComputeCallConstant(argc,
in_loop,
kind_,
extra_ic_state,
*name,
*object,
lookup->holder(),
function);
break;
}
case NORMAL: {
if (!object->IsJSObject()) return NULL;
Handle<JSObject> receiver = Handle<JSObject>::cast(object);
if (lookup->holder()->IsGlobalObject()) {
GlobalObject* global = GlobalObject::cast(lookup->holder());
JSGlobalPropertyCell* cell =
JSGlobalPropertyCell::cast(global->GetPropertyCell(lookup));
if (!cell->value()->IsJSFunction()) return NULL;
JSFunction* function = JSFunction::cast(cell->value());
maybe_code = isolate()->stub_cache()->ComputeCallGlobal(argc,
in_loop,
kind_,
*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 (lookup->holder() != *receiver) return NULL;
maybe_code = isolate()->stub_cache()->ComputeCallNormal(argc,
in_loop,
kind_,
*name,
*receiver);
}
break;
}
case INTERCEPTOR: {
ASSERT(HasInterceptorGetter(lookup->holder()));
maybe_code = isolate()->stub_cache()->ComputeCallInterceptor(
argc,
kind_,
*name,
*object,
lookup->holder());
break;
}
default:
maybe_code = NULL;
break;
}
return maybe_code;
}
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();
InLoopFlag in_loop = target()->ic_in_loop();
MaybeObject* maybe_code = NULL;
bool had_proto_failure = false;
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.
maybe_code = isolate()->stub_cache()->ComputeCallPreMonomorphic(argc,
in_loop,
kind_);
} else if (state == MONOMORPHIC) {
if (kind_ == Code::CALL_IC &&
TryUpdateExtraICState(lookup, object, &extra_ic_state)) {
maybe_code = ComputeMonomorphicStub(lookup,
state,
extra_ic_state,
object,
name);
} else if (kind_ == Code::CALL_IC &&
TryRemoveInvalidPrototypeDependentStub(target(),
*object,
*name)) {
had_proto_failure = true;
maybe_code = ComputeMonomorphicStub(lookup,
state,
extra_ic_state,
object,
name);
} else {
maybe_code = isolate()->stub_cache()->ComputeCallMegamorphic(argc,
in_loop,
kind_);
}
} else {
maybe_code = ComputeMonomorphicStub(lookup,
state,
extra_ic_state,
object,
name);
}
// If we're unable to compute the stub (not enough memory left), we
// simply avoid updating the caches.
Object* code;
if (maybe_code == NULL || !maybe_code->ToObject(&code)) 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::cast(code));
} else if (state == MEGAMORPHIC) {
// Cache code holding map should be consistent with
// GenerateMonomorphicCacheProbe. It is not the map which holds the stub.
Map* map = JSObject::cast(object->IsJSObject() ? *object :
object->GetPrototype())->map();
// Update the stub cache.
isolate()->stub_cache()->Set(*name, map, Code::cast(code));
}
USE(had_proto_failure);
#ifdef DEBUG
if (had_proto_failure) state = MONOMORPHIC_PROTOTYPE_FAILURE;
TraceIC(kind_ == Code::CALL_IC ? "CallIC" : "KeyedCallIC",
name, state, target(), in_loop ? " (in-loop)" : "");
#endif
}
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->IsAccessCheckNeeded()) {
int argc = target()->arguments_count();
InLoopFlag in_loop = target()->ic_in_loop();
MaybeObject* maybe_code = isolate()->stub_cache()->ComputeCallMegamorphic(
argc, in_loop, Code::KEYED_CALL_IC);
Object* code;
if (maybe_code->ToObject(&code)) {
set_target(Code::cast(code));
#ifdef DEBUG
TraceIC(
"KeyedCallIC", key, state, target(), in_loop ? " (in-loop)" : "");
#endif
}
}
HandleScope scope(isolate());
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 = Handle<Object>(TryCallAsFunction(*result));
if (result->IsJSFunction()) return *result;
return TypeError("property_not_function", object, key);
}
#ifdef DEBUG
#define TRACE_IC_NAMED(msg, name) \
if (FLAG_trace_ic) PrintF(msg, *(name)->ToCString())
#else
#define TRACE_IC_NAMED(msg, name)
#endif
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) {
Code* non_monomorphic_stub =
(state == UNINITIALIZED) ? pre_monomorphic_stub() : megamorphic_stub();
// 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())) {
HandleScope scope(isolate());
#ifdef DEBUG
if (FLAG_trace_ic) PrintF("[LoadIC : +#length /string]\n");
#endif
if (state == PREMONOMORPHIC) {
if (object->IsString()) {
Map* map = HeapObject::cast(*object)->map();
const int offset = String::kLengthOffset;
PatchInlinedLoad(address(), map, offset);
set_target(isolate()->builtins()->builtin(
Builtins::kLoadIC_StringLength));
} else {
set_target(isolate()->builtins()->builtin(
Builtins::kLoadIC_StringWrapperLength));
}
} else if (state == MONOMORPHIC && object->IsStringWrapper()) {
set_target(isolate()->builtins()->builtin(
Builtins::kLoadIC_StringWrapperLength));
} else {
set_target(non_monomorphic_stub);
}
// Get the string if we have a string wrapper object.
if (object->IsJSValue()) {
object = Handle<Object>(Handle<JSValue>::cast(object)->value(),
isolate());
}
return Smi::FromInt(String::cast(*object)->length());
}
// Use specialized code for getting the length of arrays.
if (object->IsJSArray() &&
name->Equals(isolate()->heap()->length_symbol())) {
#ifdef DEBUG
if (FLAG_trace_ic) PrintF("[LoadIC : +#length /array]\n");
#endif
if (state == PREMONOMORPHIC) {
Map* map = HeapObject::cast(*object)->map();
const int offset = JSArray::kLengthOffset;
PatchInlinedLoad(address(), map, offset);
set_target(isolate()->builtins()->builtin(
Builtins::kLoadIC_ArrayLength));
} else {
set_target(non_monomorphic_stub);
}
return JSArray::cast(*object)->length();
}
// Use specialized code for getting prototype of functions.
if (object->IsJSFunction() &&
name->Equals(isolate()->heap()->prototype_symbol()) &&
JSFunction::cast(*object)->should_have_prototype()) {
#ifdef DEBUG
if (FLAG_trace_ic) PrintF("[LoadIC : +#prototype /function]\n");
#endif
if (state == PREMONOMORPHIC) {
set_target(isolate()->builtins()->builtin(
Builtins::kLoadIC_FunctionPrototype));
} else {
set_target(non_monomorphic_stub);
}
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;
LookupForRead(*object, *name, &lookup);
// If we did not find a property, check if we need to throw an exception.
if (!lookup.IsProperty()) {
if (FLAG_strict || IsContextual(object)) {
return ReferenceError("not_defined", name);
}
LOG(isolate(), SuspectReadEvent(*name, *object));
}
bool can_be_inlined_precheck =
FLAG_use_ic &&
lookup.IsProperty() &&
lookup.IsCacheable() &&
lookup.holder() == *object &&
!object->IsAccessCheckNeeded();
bool can_be_inlined =
can_be_inlined_precheck &&
state == PREMONOMORPHIC &&
lookup.type() == FIELD;
bool can_be_inlined_contextual =
can_be_inlined_precheck &&
state == UNINITIALIZED &&
lookup.holder()->IsGlobalObject() &&
lookup.type() == NORMAL;
if (can_be_inlined) {
Map* map = lookup.holder()->map();
// Property's index in the properties array. If negative we have
// an inobject property.
int index = lookup.GetFieldIndex() - map->inobject_properties();
if (index < 0) {
// Index is an offset from the end of the object.
int offset = map->instance_size() + (index * kPointerSize);
if (PatchInlinedLoad(address(), map, offset)) {
set_target(megamorphic_stub());
TRACE_IC_NAMED("[LoadIC : inline patch %s]\n", name);
return lookup.holder()->FastPropertyAt(lookup.GetFieldIndex());
} else {
TRACE_IC_NAMED("[LoadIC : no inline patch %s (patching failed)]\n",
name);
}
} else {
TRACE_IC_NAMED("[LoadIC : no inline patch %s (not inobject)]\n", name);
}
} else if (can_be_inlined_contextual) {
Map* map = lookup.holder()->map();
JSGlobalPropertyCell* cell = JSGlobalPropertyCell::cast(
lookup.holder()->property_dictionary()->ValueAt(
lookup.GetDictionaryEntry()));
if (PatchInlinedContextualLoad(address(),
map,
cell,
lookup.IsDontDelete())) {
set_target(megamorphic_stub());
TRACE_IC_NAMED("[LoadIC : inline contextual patch %s]\n", name);
ASSERT(cell->value() != isolate()->heap()->the_hole_value());
return cell->value();
}
} else {
if (FLAG_use_ic && state == PREMONOMORPHIC) {
TRACE_IC_NAMED("[LoadIC : no inline patch %s (not inlinable)]\n", name);
}
}
// Update inline cache and stub cache.
if (FLAG_use_ic) {
UpdateCaches(&lookup, state, object, name);
}
PropertyAttributes attr;
if (lookup.IsProperty() && lookup.type() == INTERCEPTOR) {
// Get the property.
Object* result;
{ MaybeObject* maybe_result =
object->GetProperty(*object, &lookup, *name, &attr);
if (!maybe_result->ToObject(&result)) return maybe_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.
MaybeObject* maybe_code = NULL;
Object* 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.
maybe_code = pre_monomorphic_stub();
} else if (!lookup->IsProperty()) {
// Nonexistent property. The result is undefined.
maybe_code = isolate()->stub_cache()->ComputeLoadNonexistent(*name,
*receiver);
} else {
// Compute monomorphic stub.
switch (lookup->type()) {
case FIELD: {
maybe_code = isolate()->stub_cache()->ComputeLoadField(
*name,
*receiver,
lookup->holder(),
lookup->GetFieldIndex());
break;
}
case CONSTANT_FUNCTION: {
Object* constant = lookup->GetConstantFunction();
maybe_code = isolate()->stub_cache()->ComputeLoadConstant(
*name, *receiver, lookup->holder(), constant);
break;
}
case NORMAL: {
if (lookup->holder()->IsGlobalObject()) {
GlobalObject* global = GlobalObject::cast(lookup->holder());
JSGlobalPropertyCell* cell =
JSGlobalPropertyCell::cast(global->GetPropertyCell(lookup));
maybe_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 (lookup->holder() != *receiver) return;
maybe_code = isolate()->stub_cache()->ComputeLoadNormal();
}
break;
}
case CALLBACKS: {
if (!lookup->GetCallbackObject()->IsAccessorInfo()) return;
AccessorInfo* callback =
AccessorInfo::cast(lookup->GetCallbackObject());
if (v8::ToCData<Address>(callback->getter()) == 0) return;
maybe_code = isolate()->stub_cache()->ComputeLoadCallback(
*name, *receiver, lookup->holder(), callback);
break;
}
case INTERCEPTOR: {
ASSERT(HasInterceptorGetter(lookup->holder()));
maybe_code = isolate()->stub_cache()->ComputeLoadInterceptor(
*name, *receiver, lookup->holder());
break;
}
default:
return;
}
}
// If we're unable to compute the stub (not enough memory left), we
// simply avoid updating the caches.
if (maybe_code == NULL || !maybe_code->ToObject(&code)) return;
// Patch the call site depending on the state of the cache.
if (state == UNINITIALIZED || state == PREMONOMORPHIC ||
state == MONOMORPHIC_PROTOTYPE_FAILURE) {
set_target(Code::cast(code));
} else if (state == MONOMORPHIC) {
set_target(megamorphic_stub());
} else if (state == MEGAMORPHIC) {
// Cache code holding map should be consistent with
// GenerateMonomorphicCacheProbe.
Map* map = JSObject::cast(object->IsJSObject() ? *object :
object->GetPrototype())->map();
isolate()->stub_cache()->Set(*name, map, Code::cast(code));
}
#ifdef DEBUG
TraceIC("LoadIC", name, state, target());
#endif
}
MaybeObject* KeyedLoadIC::Load(State state,
Handle<Object> object,
Handle<Object> key) {
// Check for values that can be converted into a symbol.
// TODO(1295): Remove this code.
HandleScope scope(isolate());
if (key->IsHeapNumber() &&
isnan(HeapNumber::cast(*key)->value())) {
key = isolate()->factory()->nan_symbol();
} else if (key->IsUndefined()) {
key = isolate()->factory()->undefined_symbol();
}
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);
Object* code = NULL;
{ MaybeObject* maybe_code =
isolate()->stub_cache()->ComputeKeyedLoadStringLength(*name,
*string);
if (!maybe_code->ToObject(&code)) return maybe_code;
}
set_target(Code::cast(code));
#ifdef DEBUG
TraceIC("KeyedLoadIC", name, state, target());
#endif // DEBUG
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);
Object* code;
{ MaybeObject* maybe_code =
isolate()->stub_cache()->ComputeKeyedLoadArrayLength(*name,
*array);
if (!maybe_code->ToObject(&code)) return maybe_code;
}
set_target(Code::cast(code));
#ifdef DEBUG
TraceIC("KeyedLoadIC", name, state, target());
#endif // DEBUG
return JSArray::cast(*object)->length();
}
// Use specialized code for getting prototype of functions.
if (object->IsJSFunction() &&
name->Equals(isolate()->heap()->prototype_symbol()) &&
JSFunction::cast(*object)->should_have_prototype()) {
Handle<JSFunction> function = Handle<JSFunction>::cast(object);
Object* code;
{ MaybeObject* maybe_code =
isolate()->stub_cache()->ComputeKeyedLoadFunctionPrototype(
*name, *function);
if (!maybe_code->ToObject(&code)) return maybe_code;
}
set_target(Code::cast(code));
#ifdef DEBUG
TraceIC("KeyedLoadIC", name, state, target());
#endif // DEBUG
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)) {
HandleScope scope(isolate());
// 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;
LookupForRead(*object, *name, &lookup);
// If we did not find a property, check if we need to throw an exception.
if (!lookup.IsProperty()) {
if (FLAG_strict || IsContextual(object)) {
return ReferenceError("not_defined", name);
}
}
if (FLAG_use_ic) {
UpdateCaches(&lookup, state, object, name);
}
PropertyAttributes attr;
if (lookup.IsProperty() && lookup.type() == INTERCEPTOR) {
// Get the property.
Object* result;
{ MaybeObject* maybe_result =
object->GetProperty(*object, &lookup, *name, &attr);
if (!maybe_result->ToObject(&result)) return maybe_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) {
Code* stub = generic_stub();
if (state == UNINITIALIZED) {
if (object->IsString() && key->IsNumber()) {
stub = string_stub();
} else if (object->IsJSObject()) {
Handle<JSObject> receiver = Handle<JSObject>::cast(object);
if (receiver->HasExternalArrayElements()) {
MaybeObject* probe =
isolate()->stub_cache()->ComputeKeyedLoadOrStoreExternalArray(
*receiver, false, kNonStrictMode);
stub = probe->IsFailure() ?
NULL : Code::cast(probe->ToObjectUnchecked());
} else if (receiver->HasIndexedInterceptor()) {
stub = indexed_interceptor_stub();
} else if (key->IsSmi() &&
receiver->map()->has_fast_elements()) {
MaybeObject* probe =
isolate()->stub_cache()->ComputeKeyedLoadSpecialized(*receiver);
stub = probe->IsFailure() ?
NULL : Code::cast(probe->ToObjectUnchecked());
}
}
}
if (stub != NULL) set_target(stub);
#ifdef DEBUG
TraceIC("KeyedLoadIC", key, state, target());
#endif // DEBUG
// For JSObjects with fast elements that are not value wrappers
// and that do not have indexed interceptors, we initialize the
// inlined fast case (if present) by patching the inlined map
// check.
if (object->IsJSObject() &&
!object->IsJSValue() &&
!JSObject::cast(*object)->HasIndexedInterceptor() &&
JSObject::cast(*object)->HasFastElements()) {
Map* map = JSObject::cast(*object)->map();
PatchInlinedLoad(address(), map);
}
}
// 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.
MaybeObject* maybe_code = NULL;
Object* 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.
maybe_code = pre_monomorphic_stub();
} else {
// Compute a monomorphic stub.
switch (lookup->type()) {
case FIELD: {
maybe_code = isolate()->stub_cache()->ComputeKeyedLoadField(
*name, *receiver, lookup->holder(), lookup->GetFieldIndex());
break;
}
case CONSTANT_FUNCTION: {
Object* constant = lookup->GetConstantFunction();
maybe_code = isolate()->stub_cache()->ComputeKeyedLoadConstant(
*name, *receiver, lookup->holder(), constant);
break;
}
case CALLBACKS: {
if (!lookup->GetCallbackObject()->IsAccessorInfo()) return;
AccessorInfo* callback =
AccessorInfo::cast(lookup->GetCallbackObject());
if (v8::ToCData<Address>(callback->getter()) == 0) return;
maybe_code = isolate()->stub_cache()->ComputeKeyedLoadCallback(
*name, *receiver, lookup->holder(), callback);
break;
}
case INTERCEPTOR: {
ASSERT(HasInterceptorGetter(lookup->holder()));
maybe_code = isolate()->stub_cache()->ComputeKeyedLoadInterceptor(
*name, *receiver, lookup->holder());
break;
}
default: {
// Always rewrite to the generic case so that we do not
// repeatedly try to rewrite.
maybe_code = generic_stub();
break;
}
}
}
// If we're unable to compute the stub (not enough memory left), we
// simply avoid updating the caches.
if (maybe_code == NULL || !maybe_code->ToObject(&code)) return;
// 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::cast(code));
} else if (state == MONOMORPHIC) {
set_target(megamorphic_stub());
}
#ifdef DEBUG
TraceIC("KeyedLoadIC", name, state, target());
#endif
}
static bool StoreICableLookup(LookupResult* lookup) {
// Bail out if we didn't find a result.
if (!lookup->IsPropertyOrTransition() || !lookup->IsCacheable()) return false;
// If the property is read-only, we leave the IC in its current
// state.
if (lookup->IsReadOnly()) return false;
return true;
}
static bool LookupForWrite(JSObject* object,
String* name,
LookupResult* lookup) {
object->LocalLookup(name, lookup);
if (!StoreICableLookup(lookup)) {
return false;
}
if (lookup->type() == INTERCEPTOR) {
if (object->GetNamedInterceptor()->setter()->IsUndefined()) {
object->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 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);
}
if (!object->IsJSObject()) {
// 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 stores where the receiver is not a JSObject.
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)) {
HandleScope scope(isolate());
Handle<Object> result = SetElement(receiver, index, value, strict_mode);
if (result.is_null()) return Failure::Exception();
return *value;
}
// Use specialized code for setting the length of arrays.
if (receiver->IsJSArray()
&& name->Equals(isolate()->heap()->length_symbol())
&& receiver->AllowsSetElementsLength()) {
#ifdef DEBUG
if (FLAG_trace_ic) PrintF("[StoreIC : +#length /array]\n");
#endif
Builtins::Name target = (strict_mode == kStrictMode)
? Builtins::kStoreIC_ArrayLength_Strict
: Builtins::kStoreIC_ArrayLength;
set_target(isolate()->builtins()->builtin(target));
return receiver->SetProperty(*name, *value, NONE, strict_mode);
}
// Lookup the property locally in the receiver.
if (FLAG_use_ic && !receiver->IsJSGlobalProxy()) {
LookupResult lookup;
if (LookupForWrite(*receiver, *name, &lookup)) {
bool can_be_inlined =
state == UNINITIALIZED &&
lookup.IsProperty() &&
lookup.holder() == *receiver &&
lookup.type() == FIELD &&
!receiver->IsAccessCheckNeeded();
if (can_be_inlined) {
Map* map = lookup.holder()->map();
// Property's index in the properties array. If negative we have
// an inobject property.
int index = lookup.GetFieldIndex() - map->inobject_properties();
if (index < 0) {
// Index is an offset from the end of the object.
int offset = map->instance_size() + (index * kPointerSize);
if (PatchInlinedStore(address(), map, offset)) {
set_target((strict_mode == kStrictMode)
? megamorphic_stub_strict()
: megamorphic_stub());
#ifdef DEBUG
if (FLAG_trace_ic) {
PrintF("[StoreIC : inline patch %s]\n", *name->ToCString());
}
#endif
return receiver->SetProperty(*name, *value, NONE, strict_mode);
#ifdef DEBUG
} else {
if (FLAG_trace_ic) {
PrintF("[StoreIC : no inline patch %s (patching failed)]\n",
*name->ToCString());
}
}
} else {
if (FLAG_trace_ic) {
PrintF("[StoreIC : no inline patch %s (not inobject)]\n",
*name->ToCString());
}
}
} else {
if (state == PREMONOMORPHIC) {
if (FLAG_trace_ic) {
PrintF("[StoreIC : no inline patch %s (not inlinable)]\n",
*name->ToCString());
#endif
}
}
}
// If no inlined store ic was patched, 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.IsFound() && lookup.IsReadOnly()) {
return TypeError("strict_read_only_property", object, name);
} else if (IsContextual(object)) {
return ReferenceError("not_defined", name);
}
}
}
}
if (receiver->IsJSGlobalProxy()) {
// Generate a generic stub that goes to the runtime when we see a global
// proxy as receiver.
Code* stub = (strict_mode == kStrictMode)
? global_proxy_stub_strict()
: global_proxy_stub();
if (target() != stub) {
set_target(stub);
#ifdef DEBUG
TraceIC("StoreIC", name, state, target());
#endif
}
}
// Set the property.
return receiver->SetProperty(*name, *value, NONE, strict_mode);
}
void StoreIC::UpdateCaches(LookupResult* lookup,
State state,
StrictModeFlag strict_mode,
Handle<JSObject> receiver,
Handle<String> name,
Handle<Object> value) {
// Skip JSGlobalProxy.
ASSERT(!receiver->IsJSGlobalProxy());
ASSERT(StoreICableLookup(lookup));
// 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.
MaybeObject* maybe_code = NULL;
Object* code = NULL;
switch (type) {
case FIELD: {
maybe_code = isolate()->stub_cache()->ComputeStoreField(
*name, *receiver, lookup->GetFieldIndex(), NULL, strict_mode);
break;
}
case MAP_TRANSITION: {
if (lookup->GetAttributes() != NONE) return;
HandleScope scope(isolate());
ASSERT(type == MAP_TRANSITION);
Handle<Map> transition(lookup->GetTransitionMap());
int index = transition->PropertyIndexFor(*name);
maybe_code = isolate()->stub_cache()->ComputeStoreField(
*name, *receiver, index, *transition, 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);
JSGlobalPropertyCell* cell =
JSGlobalPropertyCell::cast(global->GetPropertyCell(lookup));
maybe_code = isolate()->stub_cache()->ComputeStoreGlobal(
*name, *global, cell, strict_mode);
} else {
if (lookup->holder() != *receiver) return;
maybe_code = isolate()->stub_cache()->ComputeStoreNormal(strict_mode);
}
break;
}
case CALLBACKS: {
if (!lookup->GetCallbackObject()->IsAccessorInfo()) return;
AccessorInfo* callback = AccessorInfo::cast(lookup->GetCallbackObject());
if (v8::ToCData<Address>(callback->setter()) == 0) return;
maybe_code = isolate()->stub_cache()->ComputeStoreCallback(
*name, *receiver, callback, strict_mode);
break;
}
case INTERCEPTOR: {
ASSERT(!receiver->GetNamedInterceptor()->setter()->IsUndefined());
maybe_code = isolate()->stub_cache()->ComputeStoreInterceptor(
*name, *receiver, strict_mode);
break;
}
default:
return;
}
// If we're unable to compute the stub (not enough memory left), we
// simply avoid updating the caches.
if (maybe_code == NULL || !maybe_code->ToObject(&code)) return;
// Patch the call site depending on the state of the cache.
if (state == UNINITIALIZED || state == MONOMORPHIC_PROTOTYPE_FAILURE) {
set_target(Code::cast(code));
} else if (state == MONOMORPHIC) {
// Only move to megamorphic if the target changes.
if (target() != Code::cast(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::cast(code));
}
#ifdef DEBUG
TraceIC("StoreIC", name, state, target());
#endif
}
MaybeObject* KeyedStoreIC::Store(State state,
StrictModeFlag strict_mode,
Handle<Object> object,
Handle<Object> key,
Handle<Object> value) {
if (key->IsSymbol()) {
Handle<String> name = Handle<String>::cast(key);
// 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)) {
HandleScope scope(isolate());
Handle<Object> result = SetElement(receiver, index, value, strict_mode);
if (result.is_null()) return Failure::Exception();
return *value;
}
// Lookup the property locally in the receiver.
LookupResult lookup;
receiver->LocalLookup(*name, &lookup);
// Update inline cache and stub cache.
if (FLAG_use_ic) {
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).
bool use_ic = FLAG_use_ic && !object->IsAccessCheckNeeded();
ASSERT(!(use_ic && object->IsJSGlobalProxy()));
if (use_ic) {
Code* stub =
(strict_mode == kStrictMode) ? generic_stub_strict() : generic_stub();
if (state == UNINITIALIZED) {
if (object->IsJSObject()) {
Handle<JSObject> receiver = Handle<JSObject>::cast(object);
if (receiver->HasExternalArrayElements()) {
MaybeObject* probe =
isolate()->stub_cache()->ComputeKeyedLoadOrStoreExternalArray(
*receiver, true, strict_mode);
stub = probe->IsFailure() ?
NULL : Code::cast(probe->ToObjectUnchecked());
} else if (key->IsSmi() && receiver->map()->has_fast_elements()) {
MaybeObject* probe =
isolate()->stub_cache()->ComputeKeyedStoreSpecialized(
*receiver, strict_mode);
stub = probe->IsFailure() ?
NULL : Code::cast(probe->ToObjectUnchecked());
}
}
}
if (stub != NULL) set_target(stub);
}
// 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) {
// Skip JSGlobalProxy.
if (receiver->IsJSGlobalProxy()) return;
// Bail out if we didn't find a result.
if (!lookup->IsPropertyOrTransition() || !lookup->IsCacheable()) return;
// If the property is read-only, we leave the IC in its current
// state.
if (lookup->IsReadOnly()) return;
// 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.
MaybeObject* maybe_code = NULL;
Object* code = NULL;
switch (type) {
case FIELD: {
maybe_code = isolate()->stub_cache()->ComputeKeyedStoreField(
*name, *receiver, lookup->GetFieldIndex(), NULL, strict_mode);
break;
}
case MAP_TRANSITION: {
if (lookup->GetAttributes() == NONE) {
HandleScope scope(isolate());
ASSERT(type == MAP_TRANSITION);
Handle<Map> transition(lookup->GetTransitionMap());
int index = transition->PropertyIndexFor(*name);
maybe_code = isolate()->stub_cache()->ComputeKeyedStoreField(
*name, *receiver, index, *transition, strict_mode);
break;
}
// fall through.
}
default: {
// Always rewrite to the generic case so that we do not
// repeatedly try to rewrite.
maybe_code = (strict_mode == kStrictMode)
? generic_stub_strict()
: generic_stub();
break;
}
}
// If we're unable to compute the stub (not enough memory left), we
// simply avoid updating the caches.
if (maybe_code == NULL || !maybe_code->ToObject(&code)) return;
// 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::cast(code));
} else if (state == MONOMORPHIC) {
set_target((strict_mode == kStrictMode)
? megamorphic_stub_strict()
: megamorphic_stub());
}
#ifdef DEBUG
TraceIC("KeyedStoreIC", name, state, target());
#endif
}
// ----------------------------------------------------------------------------
// Static IC stub generators.
//
static JSFunction* CompileFunction(Isolate* isolate,
JSFunction* function,
InLoopFlag in_loop) {
// Compile now with optimization.
HandleScope scope(isolate);
Handle<JSFunction> function_handle(function, isolate);
if (in_loop == IN_LOOP) {
CompileLazyInLoop(function_handle, CLEAR_EXCEPTION);
} else {
CompileLazy(function_handle, CLEAR_EXCEPTION);
}
return *function_handle;
}
// Used from ic-<arch>.cc.
RUNTIME_FUNCTION(MaybeObject*, CallIC_Miss) {
NoHandleAllocation na;
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));
Object* result;
if (!maybe_result->ToObject(&result)) 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 was 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. We
// do this in the case where we know that the inline cache is inside a loop,
// because then we know that we want to optimize the function.
if (!result->IsJSFunction() || JSFunction::cast(result)->is_compiled()) {
return result;
}
return CompileFunction(isolate,
JSFunction::cast(result),
ic.target()->ic_in_loop());
}
// Used from ic-<arch>.cc.
RUNTIME_FUNCTION(MaybeObject*, KeyedCallIC_Miss) {
NoHandleAllocation na;
ASSERT(args.length() == 2);
KeyedCallIC ic(isolate);
IC::State state = IC::StateFrom(ic.target(), args[0], args[1]);
Object* result;
{ MaybeObject* maybe_result =
ic.LoadFunction(state, args.at<Object>(0), args.at<Object>(1));
if (!maybe_result->ToObject(&result)) return maybe_result;
}
if (!result->IsJSFunction() || JSFunction::cast(result)->is_compiled()) {
return result;
}
return CompileFunction(isolate,
JSFunction::cast(result),
ic.target()->ic_in_loop());
}
// Used from ic-<arch>.cc.
RUNTIME_FUNCTION(MaybeObject*, LoadIC_Miss) {
NoHandleAllocation na;
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) {
NoHandleAllocation na;
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));
}
// Used from ic-<arch>.cc.
RUNTIME_FUNCTION(MaybeObject*, StoreIC_Miss) {
NoHandleAllocation na;
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,
static_cast<StrictModeFlag>(extra_ic_state & kStrictMode),
args.at<Object>(0),
args.at<String>(1),
args.at<Object>(2));
}
RUNTIME_FUNCTION(MaybeObject*, StoreIC_ArrayLength) {
NoHandleAllocation nha;
ASSERT(args.length() == 2);
JSObject* receiver = JSObject::cast(args[0]);
Object* len = args[1];
// The generated code should filter out non-Smis before we get here.
ASSERT(len->IsSmi());
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) {
NoHandleAllocation na;
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,
static_cast<StrictModeFlag>(extra_ic_state & kStrictMode),
args.at<Object>(0),
args.at<Object>(1),
args.at<Object>(2));
}
void TRBinaryOpIC::patch(Code* code) {
set_target(code);
}
const char* TRBinaryOpIC::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 STRING: return "Strings";
case GENERIC: return "Generic";
default: return "Invalid";
}
}
TRBinaryOpIC::State TRBinaryOpIC::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;
}
TRBinaryOpIC::TypeInfo TRBinaryOpIC::JoinTypes(TRBinaryOpIC::TypeInfo x,
TRBinaryOpIC::TypeInfo y) {
if (x == UNINITIALIZED) return y;
if (y == UNINITIALIZED) return x;
if (x == STRING && y == STRING) return STRING;
if (x == STRING || y == STRING) return GENERIC;
if (x >= y) return x;
return y;
}
TRBinaryOpIC::TypeInfo TRBinaryOpIC::GetTypeInfo(Handle<Object> left,
Handle<Object> 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;
}
if (left_type.IsString() || right_type.IsString()) {
// Patching for fast string ADD makes sense even if only one of the
// arguments is a string.
return STRING;
}
// Check for oddball objects.
if (left->IsUndefined() && right->IsNumber()) return ODDBALL;
if (left->IsNumber() && right->IsUndefined()) return ODDBALL;
return GENERIC;
}
// defined in code-stubs-<arch>.cc
// Only needed to remove dependency of ic.cc on code-stubs-<arch>.h.
Handle<Code> GetTypeRecordingBinaryOpStub(int key,
TRBinaryOpIC::TypeInfo type_info,
TRBinaryOpIC::TypeInfo result_type);
RUNTIME_FUNCTION(MaybeObject*, TypeRecordingBinaryOp_Patch) {
ASSERT(args.length() == 5);
HandleScope scope(isolate);
Handle<Object> left = args.at<Object>(0);
Handle<Object> right = args.at<Object>(1);
int key = Smi::cast(args[2])->value();
Token::Value op = static_cast<Token::Value>(Smi::cast(args[3])->value());
TRBinaryOpIC::TypeInfo previous_type =
static_cast<TRBinaryOpIC::TypeInfo>(Smi::cast(args[4])->value());
TRBinaryOpIC::TypeInfo type = TRBinaryOpIC::GetTypeInfo(left, right);
type = TRBinaryOpIC::JoinTypes(type, previous_type);
TRBinaryOpIC::TypeInfo result_type = TRBinaryOpIC::UNINITIALIZED;
if (type == TRBinaryOpIC::STRING && op != Token::ADD) {
type = TRBinaryOpIC::GENERIC;
}
if (type == TRBinaryOpIC::SMI &&
previous_type == TRBinaryOpIC::SMI) {
if (op == Token::DIV || op == Token::MUL || 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 = TRBinaryOpIC::HEAP_NUMBER;
} else {
// Other operations on SMIs that overflow yield int32s.
result_type = TRBinaryOpIC::INT32;
}
}
if (type == TRBinaryOpIC::INT32 &&
previous_type == TRBinaryOpIC::INT32) {
// We must be here because an operation on two INT32 types overflowed.
result_type = TRBinaryOpIC::HEAP_NUMBER;
}
Handle<Code> code = GetTypeRecordingBinaryOpStub(key, type, result_type);
if (!code.is_null()) {
if (FLAG_trace_ic) {
PrintF("[TypeRecordingBinaryOpIC (%s->(%s->%s))#%s]\n",
TRBinaryOpIC::GetName(previous_type),
TRBinaryOpIC::GetName(type),
TRBinaryOpIC::GetName(result_type),
Token::Name(op));
}
TRBinaryOpIC ic(isolate);
ic.patch(*code);
// Activate inlined smi code.
if (previous_type == TRBinaryOpIC::UNINITIALIZED) {
PatchInlinedSmiCode(ic.address());
}
}
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;
Object** builtin_args[] = { right.location() };
Handle<Object> result = Execution::Call(builtin_function,
left,
ARRAY_SIZE(builtin_args),
builtin_args,
&caught_exception);
if (caught_exception) {
return Failure::Exception();
}
return *result;
}
Handle<Code> 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<State>(target->compare_state());
}
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 GENERIC: return "GENERIC";
default:
UNREACHABLE();
return NULL;
}
}
CompareIC::State CompareIC::TargetState(State state,
bool has_inlined_smi_code,
Handle<Object> x,
Handle<Object> y) {
if (!has_inlined_smi_code && state != UNINITIALIZED) return GENERIC;
if (state == UNINITIALIZED && x->IsSmi() && y->IsSmi()) return SMIS;
if ((state == UNINITIALIZED || (state == SMIS && has_inlined_smi_code)) &&
x->IsNumber() && y->IsNumber()) return HEAP_NUMBERS;
if (op_ != Token::EQ && op_ != Token::EQ_STRICT) return GENERIC;
if (state == UNINITIALIZED &&
x->IsJSObject() && y->IsJSObject()) return OBJECTS;
return GENERIC;
}
// Used from ic_<arch>.cc.
RUNTIME_FUNCTION(Code*, CompareIC_Miss) {
NoHandleAllocation na;
ASSERT(args.length() == 3);
CompareIC ic(isolate, static_cast<Token::Value>(Smi::cast(args[2])->value()));
ic.UpdateCaches(args.at<Object>(0), args.at<Object>(1));
return ic.target();
}
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