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// Copyright 2012 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#if defined(V8_OS_STARBOARD)
#include "starboard/client_porting/poem/stdio_leaks_poem.h"
#endif
#include "src/ic/ic.h"
#include "src/accessors.h"
#include "src/api-arguments-inl.h"
#include "src/api.h"
#include "src/arguments.h"
#include "src/base/bits.h"
#include "src/conversions.h"
#include "src/execution.h"
#include "src/field-type.h"
#include "src/frames-inl.h"
#include "src/ic/call-optimization.h"
#include "src/ic/handler-configuration-inl.h"
#include "src/ic/ic-inl.h"
#include "src/ic/ic-stats.h"
#include "src/ic/stub-cache.h"
#include "src/isolate-inl.h"
#include "src/macro-assembler.h"
#include "src/prototype.h"
#include "src/runtime-profiler.h"
#include "src/runtime/runtime-utils.h"
#include "src/runtime/runtime.h"
#include "src/tracing/trace-event.h"
#include "src/tracing/tracing-category-observer.h"
namespace v8 {
namespace internal {
char IC::TransitionMarkFromState(IC::State state) {
switch (state) {
case UNINITIALIZED:
return '0';
case PREMONOMORPHIC:
return '.';
case MONOMORPHIC:
return '1';
case RECOMPUTE_HANDLER:
return '^';
case POLYMORPHIC:
return 'P';
case MEGAMORPHIC:
return 'N';
case GENERIC:
return 'G';
}
UNREACHABLE();
}
namespace {
const char* GetModifier(KeyedAccessLoadMode mode) {
if (mode == LOAD_IGNORE_OUT_OF_BOUNDS) return ".IGNORE_OOB";
return "";
}
const char* GetModifier(KeyedAccessStoreMode mode) {
if (mode == STORE_NO_TRANSITION_HANDLE_COW) return ".COW";
if (mode == STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS) {
return ".IGNORE_OOB";
}
if (IsGrowStoreMode(mode)) return ".GROW";
return "";
}
} // namespace
#define TRACE_GENERIC_IC(reason) set_slow_stub_reason(reason);
void IC::TraceIC(const char* type, Handle<Object> name) {
if (FLAG_ic_stats) {
if (AddressIsDeoptimizedCode()) return;
State new_state = nexus()->StateFromFeedback();
TraceIC(type, name, state(), new_state);
}
}
void IC::TraceIC(const char* type, Handle<Object> name, State old_state,
State new_state) {
if (V8_LIKELY(!FLAG_ic_stats)) return;
Map* map = nullptr;
if (!receiver_map().is_null()) {
map = *receiver_map();
}
const char* modifier = "";
if (IsKeyedLoadIC()) {
KeyedAccessLoadMode mode =
casted_nexus<KeyedLoadICNexus>()->GetKeyedAccessLoadMode();
modifier = GetModifier(mode);
} else if (IsKeyedStoreIC()) {
KeyedAccessStoreMode mode =
casted_nexus<KeyedStoreICNexus>()->GetKeyedAccessStoreMode();
modifier = GetModifier(mode);
}
if (!(FLAG_ic_stats &
v8::tracing::TracingCategoryObserver::ENABLED_BY_TRACING)) {
LOG(isolate(), ICEvent(type, is_keyed(), map, *name,
TransitionMarkFromState(old_state),
TransitionMarkFromState(new_state), modifier,
slow_stub_reason_));
return;
}
ICStats::instance()->Begin();
ICInfo& ic_info = ICStats::instance()->Current();
ic_info.type = is_keyed() ? "Keyed" : "";
ic_info.type += type;
Object* maybe_function =
Memory::Object_at(fp_ + JavaScriptFrameConstants::kFunctionOffset);
DCHECK(maybe_function->IsJSFunction());
JSFunction* function = JSFunction::cast(maybe_function);
int code_offset = 0;
if (function->IsInterpreted()) {
code_offset = InterpretedFrame::GetBytecodeOffset(fp());
} else {
code_offset =
static_cast<int>(pc() - function->code()->instruction_start());
}
JavaScriptFrame::CollectFunctionAndOffsetForICStats(
function, function->abstract_code(), code_offset);
// Reserve enough space for IC transition state, the longest length is 17.
ic_info.state.reserve(17);
ic_info.state = "(";
ic_info.state += TransitionMarkFromState(old_state);
ic_info.state += "->";
ic_info.state += TransitionMarkFromState(new_state);
ic_info.state += modifier;
ic_info.state += ")";
ic_info.map = reinterpret_cast<void*>(map);
if (map != nullptr) {
ic_info.is_dictionary_map = map->is_dictionary_map();
ic_info.number_of_own_descriptors = map->NumberOfOwnDescriptors();
ic_info.instance_type = std::to_string(map->instance_type());
}
// TODO(lpy) Add name as key field in ICStats.
ICStats::instance()->End();
}
#define TRACE_IC(type, name) TraceIC(type, name)
IC::IC(FrameDepth depth, Isolate* isolate, FeedbackNexus* nexus)
: isolate_(isolate),
vector_set_(false),
kind_(FeedbackSlotKind::kInvalid),
target_maps_set_(false),
slow_stub_reason_(nullptr),
nexus_(nexus) {
// 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 and a ~25% speedup of gbemu with the '--nouse-ic' flag.
const Address entry = Isolate::c_entry_fp(isolate->thread_local_top());
Address* constant_pool = nullptr;
if (FLAG_enable_embedded_constant_pool) {
constant_pool = reinterpret_cast<Address*>(
entry + ExitFrameConstants::kConstantPoolOffset);
}
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) {
if (FLAG_enable_embedded_constant_pool) {
constant_pool = reinterpret_cast<Address*>(
fp + StandardFrameConstants::kConstantPoolOffset);
}
const int kCallerPCOffset = StandardFrameConstants::kCallerPCOffset;
pc_address = reinterpret_cast<Address*>(fp + kCallerPCOffset);
fp = Memory::Address_at(fp + StandardFrameConstants::kCallerFPOffset);
}
#ifdef DEBUG
StackFrameIterator it(isolate);
for (int i = 0; i < depth + 1; i++) it.Advance();
StackFrame* frame = it.frame();
DCHECK(fp == frame->fp() && pc_address == frame->pc_address());
#endif
// For interpreted functions, some bytecode handlers construct a
// frame. We have to skip the constructed frame to find the interpreted
// function's frame. Check if the there is an additional frame, and if there
// is skip this frame. However, the pc should not be updated. The call to
// ICs happen from bytecode handlers.
intptr_t frame_marker =
Memory::intptr_at(fp + TypedFrameConstants::kFrameTypeOffset);
if (frame_marker == StackFrame::TypeToMarker(StackFrame::STUB)) {
fp = Memory::Address_at(fp + TypedFrameConstants::kCallerFPOffset);
}
fp_ = fp;
if (FLAG_enable_embedded_constant_pool) {
constant_pool_address_ = constant_pool;
}
pc_address_ = StackFrame::ResolveReturnAddressLocation(pc_address);
DCHECK_NOT_NULL(nexus);
kind_ = nexus->kind();
state_ = nexus->StateFromFeedback();
old_state_ = state_;
}
JSFunction* IC::GetHostFunction() const {
// 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(isolate());
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.
return frame->function();
}
static void LookupForRead(LookupIterator* it) {
for (; it->IsFound(); it->Next()) {
switch (it->state()) {
case LookupIterator::NOT_FOUND:
case LookupIterator::TRANSITION:
UNREACHABLE();
case LookupIterator::JSPROXY:
return;
case LookupIterator::INTERCEPTOR: {
// If there is a getter, return; otherwise loop to perform the lookup.
Handle<JSObject> holder = it->GetHolder<JSObject>();
if (!holder->GetNamedInterceptor()->getter()->IsUndefined(
it->isolate())) {
return;
}
break;
}
case LookupIterator::ACCESS_CHECK:
// ICs know how to perform access checks on global proxies.
if (it->GetHolder<JSObject>()->IsJSGlobalProxy() && it->HasAccess()) {
break;
}
return;
case LookupIterator::ACCESSOR:
case LookupIterator::INTEGER_INDEXED_EXOTIC:
case LookupIterator::DATA:
return;
}
}
}
bool IC::ShouldRecomputeHandler(Handle<String> name) {
if (!RecomputeHandlerForName(name)) return false;
maybe_handler_ = nexus()->FindHandlerForMap(receiver_map());
// This is a contextual access, always just update the handler and stay
// monomorphic.
if (IsGlobalIC()) return true;
// The current map wasn't handled yet. There's no reason to stay monomorphic,
// *unless* we're moving from a deprecated map to its replacement, or
// to a more general elements kind.
// TODO(verwaest): Check if the current map is actually what the old map
// would transition to.
if (maybe_handler_.is_null()) {
if (!receiver_map()->IsJSObjectMap()) return false;
Map* first_map = FirstTargetMap();
if (first_map == nullptr) return false;
Handle<Map> old_map(first_map);
if (old_map->is_deprecated()) return true;
return IsMoreGeneralElementsKindTransition(old_map->elements_kind(),
receiver_map()->elements_kind());
}
return true;
}
bool IC::RecomputeHandlerForName(Handle<Object> name) {
if (is_keyed()) {
// Determine whether the failure is due to a name failure.
if (!name->IsName()) return false;
Name* stub_name = nexus()->FindFirstName();
if (*name != stub_name) return false;
}
return true;
}
void IC::UpdateState(Handle<Object> receiver, Handle<Object> name) {
update_receiver_map(receiver);
if (!name->IsString()) return;
if (state() != MONOMORPHIC && state() != POLYMORPHIC) return;
if (receiver->IsNullOrUndefined(isolate())) return;
// Remove the target from the code cache if it became invalid
// because of changes in the prototype chain to avoid hitting it
// again.
if (ShouldRecomputeHandler(Handle<String>::cast(name))) {
MarkRecomputeHandler(name);
}
}
MaybeHandle<Object> IC::TypeError(MessageTemplate::Template index,
Handle<Object> object, Handle<Object> key) {
HandleScope scope(isolate());
THROW_NEW_ERROR(isolate(), NewTypeError(index, key, object), Object);
}
MaybeHandle<Object> IC::ReferenceError(Handle<Name> name) {
HandleScope scope(isolate());
THROW_NEW_ERROR(
isolate(), NewReferenceError(MessageTemplate::kNotDefined, name), Object);
}
// static
void IC::OnFeedbackChanged(Isolate* isolate, FeedbackVector* vector,
FeedbackSlot slot, JSFunction* host_function,
const char* reason) {
if (FLAG_trace_opt_verbose) {
// TODO(leszeks): The host function is only needed for this print, we could
// remove it as a parameter if we're of with removing this trace (or only
// tracing the feedback vector, not the function name).
if (vector->profiler_ticks() != 0) {
PrintF("[resetting ticks for ");
host_function->ShortPrint();
PrintF(" due from %d due to IC change: %s]\n", vector->profiler_ticks(),
reason);
}
}
vector->set_profiler_ticks(0);
#ifdef V8_TRACE_FEEDBACK_UPDATES
if (FLAG_trace_feedback_updates) {
int slot_count = vector->metadata()->slot_count();
OFStream os(stdout);
if (slot.IsInvalid()) {
os << "[Feedback slots in ";
} else {
os << "[Feedback slot " << slot.ToInt() << "/" << slot_count << " in ";
}
vector->shared_function_info()->ShortPrint(os);
if (slot.IsInvalid()) {
os << " updated - ";
} else {
os << " updated to ";
vector->FeedbackSlotPrint(os, slot);
os << " - ";
}
os << reason << "]" << std::endl;
}
#endif
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.
}
static bool MigrateDeprecated(Handle<Object> object) {
if (!object->IsJSObject()) return false;
Handle<JSObject> receiver = Handle<JSObject>::cast(object);
if (!receiver->map()->is_deprecated()) return false;
JSObject::MigrateInstance(Handle<JSObject>::cast(object));
return true;
}
bool IC::ConfigureVectorState(IC::State new_state, Handle<Object> key) {
bool changed = true;
if (new_state == PREMONOMORPHIC) {
nexus()->ConfigurePremonomorphic();
} else if (new_state == MEGAMORPHIC) {
DCHECK_IMPLIES(!is_keyed(), key->IsName());
// Even though we don't change the feedback data, we still want to reset the
// profiler ticks. Real-world observations suggest that optimizing these
// functions doesn't improve performance.
changed = nexus()->ConfigureMegamorphic(key->IsName() ? PROPERTY : ELEMENT);
} else {
UNREACHABLE();
}
vector_set_ = true;
OnFeedbackChanged(
isolate(), *vector(), slot(), GetHostFunction(),
new_state == PREMONOMORPHIC ? "Premonomorphic" : "Megamorphic");
return changed;
}
void IC::ConfigureVectorState(Handle<Name> name, Handle<Map> map,
Handle<Object> handler) {
if (IsLoadGlobalIC()) {
LoadGlobalICNexus* nexus = casted_nexus<LoadGlobalICNexus>();
nexus->ConfigureHandlerMode(handler);
} else if (IsStoreGlobalIC()) {
StoreGlobalICNexus* nexus = casted_nexus<StoreGlobalICNexus>();
nexus->ConfigureHandlerMode(handler);
} else {
// Non-keyed ICs don't track the name explicitly.
if (!is_keyed()) name = Handle<Name>::null();
nexus()->ConfigureMonomorphic(name, map, handler);
}
vector_set_ = true;
OnFeedbackChanged(isolate(), *vector(), slot(), GetHostFunction(),
IsLoadGlobalIC() ? "LoadGlobal" : "Monomorphic");
}
void IC::ConfigureVectorState(Handle<Name> name, MapHandles const& maps,
ObjectHandles* handlers) {
DCHECK(!IsGlobalIC());
// Non-keyed ICs don't track the name explicitly.
if (!is_keyed()) name = Handle<Name>::null();
nexus()->ConfigurePolymorphic(name, maps, handlers);
vector_set_ = true;
OnFeedbackChanged(isolate(), *vector(), slot(), GetHostFunction(),
"Polymorphic");
}
MaybeHandle<Object> LoadIC::Load(Handle<Object> object, Handle<Name> 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->IsNullOrUndefined(isolate())) {
if (FLAG_use_ic && state() != PREMONOMORPHIC) {
// Ensure the IC state progresses.
TRACE_HANDLER_STATS(isolate(), LoadIC_NonReceiver);
update_receiver_map(object);
PatchCache(name, slow_stub());
TRACE_IC("LoadIC", name);
}
if (*name == isolate()->heap()->iterator_symbol()) {
return Runtime::ThrowIteratorError(isolate(), object);
}
return TypeError(MessageTemplate::kNonObjectPropertyLoad, object, name);
}
bool use_ic = MigrateDeprecated(object) ? false : FLAG_use_ic;
if (state() != UNINITIALIZED) {
JSObject::MakePrototypesFast(object, kStartAtReceiver, isolate());
update_receiver_map(object);
}
// Named lookup in the object.
LookupIterator it(object, name);
LookupForRead(&it);
if (it.IsFound() || !ShouldThrowReferenceError()) {
// Update inline cache and stub cache.
if (use_ic) UpdateCaches(&it);
// Get the property.
Handle<Object> result;
ASSIGN_RETURN_ON_EXCEPTION(isolate(), result, Object::GetProperty(&it),
Object);
if (it.IsFound()) {
return result;
} else if (!ShouldThrowReferenceError()) {
LOG(isolate(), SuspectReadEvent(*name, *object));
return result;
}
}
return ReferenceError(name);
}
MaybeHandle<Object> LoadGlobalIC::Load(Handle<Name> name) {
Handle<JSGlobalObject> global = isolate()->global_object();
if (name->IsString()) {
// Look up in script context table.
Handle<String> str_name = Handle<String>::cast(name);
Handle<ScriptContextTable> script_contexts(
global->native_context()->script_context_table());
ScriptContextTable::LookupResult lookup_result;
if (ScriptContextTable::Lookup(script_contexts, str_name, &lookup_result)) {
Handle<Object> result =
FixedArray::get(*ScriptContextTable::GetContext(
script_contexts, lookup_result.context_index),
lookup_result.slot_index, isolate());
if (result->IsTheHole(isolate())) {
// Do not install stubs and stay pre-monomorphic for
// uninitialized accesses.
return ReferenceError(name);
}
if (FLAG_use_ic) {
LoadGlobalICNexus* nexus = casted_nexus<LoadGlobalICNexus>();
if (nexus->ConfigureLexicalVarMode(lookup_result.context_index,
lookup_result.slot_index)) {
TRACE_HANDLER_STATS(isolate(), LoadGlobalIC_LoadScriptContextField);
} else {
// Given combination of indices can't be encoded, so use slow stub.
TRACE_HANDLER_STATS(isolate(), LoadGlobalIC_SlowStub);
PatchCache(name, slow_stub());
}
TRACE_IC("LoadGlobalIC", name);
}
return result;
}
}
return LoadIC::Load(global, name);
}
static bool AddOneReceiverMapIfMissing(MapHandles* receiver_maps,
Handle<Map> new_receiver_map) {
DCHECK(!new_receiver_map.is_null());
for (Handle<Map> map : *receiver_maps) {
if (!map.is_null() && map.is_identical_to(new_receiver_map)) {
return false;
}
}
receiver_maps->push_back(new_receiver_map);
return true;
}
bool IC::UpdatePolymorphicIC(Handle<Name> name, Handle<Object> handler) {
DCHECK(IsHandler(*handler));
if (is_keyed() && state() != RECOMPUTE_HANDLER) {
if (nexus()->FindFirstName() != *name) return false;
}
Handle<Map> map = receiver_map();
MapHandles maps;
ObjectHandles handlers;
TargetMaps(&maps);
int number_of_maps = static_cast<int>(maps.size());
int deprecated_maps = 0;
int handler_to_overwrite = -1;
if (!nexus()->FindHandlers(&handlers, number_of_maps)) return false;
for (int i = 0; i < number_of_maps; i++) {
Handle<Map> current_map = maps.at(i);
if (current_map->is_deprecated()) {
// Filter out deprecated maps to ensure their instances get migrated.
++deprecated_maps;
} else if (map.is_identical_to(current_map)) {
// If both map and handler stayed the same (and the name is also the
// same as checked above, for keyed accesses), we're not progressing
// in the lattice and need to go MEGAMORPHIC instead. There's one
// exception to this rule, which is when we're in RECOMPUTE_HANDLER
// state, there we allow to migrate to a new handler.
if (handler.is_identical_to(handlers[i]) &&
state() != RECOMPUTE_HANDLER) {
return false;
}
// If the receiver type is already in the polymorphic IC, this indicates
// there was a prototoype chain failure. In that case, just overwrite the
// handler.
handler_to_overwrite = i;
} else if (handler_to_overwrite == -1 &&
IsTransitionOfMonomorphicTarget(*current_map, *map)) {
handler_to_overwrite = i;
}
}
int number_of_valid_maps =
number_of_maps - deprecated_maps - (handler_to_overwrite != -1);
if (number_of_valid_maps >= kMaxPolymorphicMapCount) return false;
if (number_of_maps == 0 && state() != MONOMORPHIC && state() != POLYMORPHIC) {
return false;
}
number_of_valid_maps++;
if (number_of_valid_maps == 1) {
ConfigureVectorState(name, receiver_map(), handler);
} else {
if (is_keyed() && nexus()->FindFirstName() != *name) return false;
if (handler_to_overwrite >= 0) {
handlers[handler_to_overwrite] = handler;
if (!map.is_identical_to(maps.at(handler_to_overwrite))) {
maps[handler_to_overwrite] = map;
}
} else {
maps.push_back(map);
handlers.push_back(handler);
}
ConfigureVectorState(name, maps, &handlers);
}
return true;
}
void IC::UpdateMonomorphicIC(Handle<Object> handler, Handle<Name> name) {
DCHECK(IsHandler(*handler));
ConfigureVectorState(name, receiver_map(), handler);
}
void IC::CopyICToMegamorphicCache(Handle<Name> name) {
MapHandles maps;
ObjectHandles handlers;
TargetMaps(&maps);
if (!nexus()->FindHandlers(&handlers, static_cast<int>(maps.size()))) return;
for (int i = 0; i < static_cast<int>(maps.size()); i++) {
UpdateMegamorphicCache(*maps.at(i), *name, *handlers.at(i));
}
}
bool IC::IsTransitionOfMonomorphicTarget(Map* source_map, Map* target_map) {
if (source_map == nullptr) return true;
if (target_map == nullptr) return false;
if (source_map->is_abandoned_prototype_map()) return false;
ElementsKind target_elements_kind = target_map->elements_kind();
bool more_general_transition = IsMoreGeneralElementsKindTransition(
source_map->elements_kind(), target_elements_kind);
Map* transitioned_map = nullptr;
if (more_general_transition) {
MapHandles map_list;
map_list.push_back(handle(target_map));
transitioned_map = source_map->FindElementsKindTransitionedMap(map_list);
}
return transitioned_map == target_map;
}
void IC::PatchCache(Handle<Name> name, Handle<Object> handler) {
DCHECK(IsHandler(*handler));
// Currently only load and store ICs support non-code handlers.
DCHECK(IsAnyLoad() || IsAnyStore());
switch (state()) {
case UNINITIALIZED:
case PREMONOMORPHIC:
UpdateMonomorphicIC(handler, name);
break;
case RECOMPUTE_HANDLER:
case MONOMORPHIC:
if (IsGlobalIC()) {
UpdateMonomorphicIC(handler, name);
break;
}
// Fall through.
case POLYMORPHIC:
if (UpdatePolymorphicIC(name, handler)) break;
if (!is_keyed() || state() == RECOMPUTE_HANDLER) {
CopyICToMegamorphicCache(name);
}
ConfigureVectorState(MEGAMORPHIC, name);
// Fall through.
case MEGAMORPHIC:
UpdateMegamorphicCache(*receiver_map(), *name, *handler);
// Indicate that we've handled this case.
vector_set_ = true;
break;
case GENERIC:
UNREACHABLE();
break;
}
}
void LoadIC::UpdateCaches(LookupIterator* lookup) {
if (state() == UNINITIALIZED && !IsLoadGlobalIC()) {
// This is the first time we execute this inline cache. Set the target to
// the pre monomorphic stub to delay setting the monomorphic state.
TRACE_HANDLER_STATS(isolate(), LoadIC_Premonomorphic);
ConfigureVectorState(PREMONOMORPHIC, Handle<Object>());
TRACE_IC("LoadIC", lookup->name());
return;
}
Handle<Object> code;
if (lookup->state() == LookupIterator::ACCESS_CHECK) {
code = slow_stub();
} else if (!lookup->IsFound()) {
TRACE_HANDLER_STATS(isolate(), LoadIC_LoadNonexistentDH);
Handle<Smi> smi_handler = LoadHandler::LoadNonExistent(isolate());
code = LoadHandler::LoadFullChain(isolate(), receiver_map(),
isolate()->factory()->null_value(),
smi_handler);
} else {
if (IsLoadGlobalIC()) {
if (lookup->TryLookupCachedProperty()) {
DCHECK_EQ(LookupIterator::DATA, lookup->state());
}
if (lookup->state() == LookupIterator::DATA &&
lookup->GetReceiver().is_identical_to(lookup->GetHolder<Object>())) {
DCHECK(lookup->GetReceiver()->IsJSGlobalObject());
// Now update the cell in the feedback vector.
LoadGlobalICNexus* nexus = casted_nexus<LoadGlobalICNexus>();
nexus->ConfigurePropertyCellMode(lookup->GetPropertyCell());
TRACE_IC("LoadGlobalIC", lookup->name());
return;
}
}
code = ComputeHandler(lookup);
}
PatchCache(lookup->name(), code);
TRACE_IC("LoadIC", lookup->name());
}
StubCache* IC::stub_cache() {
if (IsAnyLoad()) {
return isolate()->load_stub_cache();
} else {
DCHECK(IsAnyStore());
return isolate()->store_stub_cache();
}
}
void IC::UpdateMegamorphicCache(Map* map, Name* name, Object* handler) {
stub_cache()->Set(name, map, handler);
}
void IC::TraceHandlerCacheHitStats(LookupIterator* lookup) {
DCHECK_EQ(LookupIterator::ACCESSOR, lookup->state());
if (V8_LIKELY(!FLAG_runtime_stats)) return;
if (IsAnyLoad()) {
TRACE_HANDLER_STATS(isolate(), LoadIC_HandlerCacheHit_Accessor);
} else {
DCHECK(IsAnyStore());
TRACE_HANDLER_STATS(isolate(), StoreIC_HandlerCacheHit_Accessor);
}
}
Handle<Object> LoadIC::ComputeHandler(LookupIterator* lookup) {
Handle<Object> receiver = lookup->GetReceiver();
if (receiver->IsString() &&
*lookup->name() == isolate()->heap()->length_string()) {
TRACE_HANDLER_STATS(isolate(), LoadIC_StringLength);
return BUILTIN_CODE(isolate(), LoadIC_StringLength);
}
if (receiver->IsStringWrapper() &&
*lookup->name() == isolate()->heap()->length_string()) {
TRACE_HANDLER_STATS(isolate(), LoadIC_StringWrapperLength);
return BUILTIN_CODE(isolate(), LoadIC_StringWrapperLength);
}
// Use specialized code for getting prototype of functions.
if (receiver->IsJSFunction() &&
*lookup->name() == isolate()->heap()->prototype_string() &&
JSFunction::cast(*receiver)->has_prototype_slot() &&
!JSFunction::cast(*receiver)->map()->has_non_instance_prototype()) {
Handle<Code> stub;
TRACE_HANDLER_STATS(isolate(), LoadIC_FunctionPrototypeStub);
return BUILTIN_CODE(isolate(), LoadIC_FunctionPrototype);
}
Handle<Map> map = receiver_map();
Handle<JSObject> holder;
bool receiver_is_holder;
if (lookup->state() != LookupIterator::JSPROXY) {
holder = lookup->GetHolder<JSObject>();
receiver_is_holder = receiver.is_identical_to(holder);
}
switch (lookup->state()) {
case LookupIterator::INTERCEPTOR: {
Handle<Smi> smi_handler = LoadHandler::LoadInterceptor(isolate());
if (holder->GetNamedInterceptor()->non_masking()) {
Handle<Object> holder_ref = isolate()->factory()->null_value();
if (!receiver_is_holder || IsLoadGlobalIC()) {
holder_ref = Map::GetOrCreatePrototypeWeakCell(holder, isolate());
}
TRACE_HANDLER_STATS(isolate(), LoadIC_LoadNonMaskingInterceptorDH);
return LoadHandler::LoadFullChain(isolate(), map, holder_ref,
smi_handler);
}
if (receiver_is_holder) {
DCHECK(map->has_named_interceptor());
TRACE_HANDLER_STATS(isolate(), LoadIC_LoadInterceptorDH);
return smi_handler;
}
TRACE_HANDLER_STATS(isolate(), LoadIC_LoadInterceptorFromPrototypeDH);
return LoadHandler::LoadFromPrototype(isolate(), map, holder,
smi_handler);
}
case LookupIterator::ACCESSOR: {
// Use simple field loads for some well-known callback properties.
// The method will only return true for absolute truths based on the
// receiver maps.
FieldIndex index;
if (Accessors::IsJSObjectFieldAccessor(map, lookup->name(), &index)) {
TRACE_HANDLER_STATS(isolate(), LoadIC_LoadFieldDH);
return LoadHandler::LoadField(isolate(), index);
}
if (holder->IsJSModuleNamespace()) {
Handle<ObjectHashTable> exports(
Handle<JSModuleNamespace>::cast(holder)->module()->exports(),
isolate());
int entry = exports->FindEntry(isolate(), lookup->name(),
Smi::ToInt(lookup->name()->GetHash()));
// We found the accessor, so the entry must exist.
DCHECK_NE(entry, ObjectHashTable::kNotFound);
int index = ObjectHashTable::EntryToValueIndex(entry);
return LoadHandler::LoadModuleExport(isolate(), index);
}
Handle<Object> accessors = lookup->GetAccessors();
if (accessors->IsAccessorPair()) {
if (lookup->TryLookupCachedProperty()) {
DCHECK_EQ(LookupIterator::DATA, lookup->state());
return ComputeHandler(lookup);
}
// When debugging we need to go the slow path to flood the accessor.
if (GetHostFunction()->shared()->HasBreakInfo()) {
TRACE_HANDLER_STATS(isolate(), LoadIC_SlowStub);
return slow_stub();
}
Handle<Object> getter(AccessorPair::cast(*accessors)->getter(),
isolate());
if (!getter->IsJSFunction() && !getter->IsFunctionTemplateInfo()) {
TRACE_HANDLER_STATS(isolate(), LoadIC_SlowStub);
return slow_stub();
}
Handle<Smi> smi_handler;
CallOptimization call_optimization(getter);
if (call_optimization.is_simple_api_call()) {
if (!call_optimization.IsCompatibleReceiverMap(map, holder) ||
!holder->HasFastProperties()) {
TRACE_HANDLER_STATS(isolate(), LoadIC_SlowStub);
return slow_stub();
}
CallOptimization::HolderLookup holder_lookup;
call_optimization.LookupHolderOfExpectedType(map, &holder_lookup);
smi_handler = LoadHandler::LoadApiGetter(
isolate(), holder_lookup == CallOptimization::kHolderIsReceiver);
Handle<Context> context(
call_optimization.GetAccessorContext(holder->map()));
Handle<WeakCell> context_cell =
isolate()->factory()->NewWeakCell(context);
Handle<WeakCell> data_cell = isolate()->factory()->NewWeakCell(
call_optimization.api_call_info());
TRACE_HANDLER_STATS(isolate(), LoadIC_LoadApiGetterFromPrototypeDH);
return LoadHandler::LoadFromPrototype(
isolate(), map, holder, smi_handler, data_cell, context_cell);
}
if (holder->HasFastProperties()) {
smi_handler =
LoadHandler::LoadAccessor(isolate(), lookup->GetAccessorIndex());
TRACE_HANDLER_STATS(isolate(), LoadIC_LoadAccessorDH);
if (receiver_is_holder) return smi_handler;
TRACE_HANDLER_STATS(isolate(), LoadIC_LoadAccessorFromPrototypeDH);
} else if (holder->IsJSGlobalObject()) {
TRACE_HANDLER_STATS(isolate(), LoadIC_LoadGlobalFromPrototypeDH);
smi_handler = LoadHandler::LoadGlobal(isolate());
Handle<WeakCell> cell =
isolate()->factory()->NewWeakCell(lookup->GetPropertyCell());
return LoadHandler::LoadFromPrototype(isolate(), map, holder,
smi_handler, cell);
} else {
smi_handler = LoadHandler::LoadNormal(isolate());
TRACE_HANDLER_STATS(isolate(), LoadIC_LoadNormalDH);
if (receiver_is_holder) return smi_handler;
TRACE_HANDLER_STATS(isolate(), LoadIC_LoadNormalFromPrototypeDH);
}
return LoadHandler::LoadFromPrototype(isolate(), map, holder,
smi_handler);
}
Handle<AccessorInfo> info = Handle<AccessorInfo>::cast(accessors);
if (v8::ToCData<Address>(info->getter()) == nullptr ||
!AccessorInfo::IsCompatibleReceiverMap(isolate(), info, map) ||
!holder->HasFastProperties() ||
(info->is_sloppy() && !receiver->IsJSReceiver())) {
TRACE_HANDLER_STATS(isolate(), LoadIC_SlowStub);
return slow_stub();
}
Handle<Smi> smi_handler = LoadHandler::LoadNativeDataProperty(
isolate(), lookup->GetAccessorIndex());
TRACE_HANDLER_STATS(isolate(), LoadIC_LoadNativeDataPropertyDH);
if (receiver_is_holder) return smi_handler;
TRACE_HANDLER_STATS(isolate(),
LoadIC_LoadNativeDataPropertyFromPrototypeDH);
return LoadHandler::LoadFromPrototype(isolate(), map, holder,
smi_handler);
}
case LookupIterator::DATA: {
DCHECK_EQ(kData, lookup->property_details().kind());
Handle<Smi> smi_handler;
if (lookup->is_dictionary_holder()) {
if (holder->IsJSGlobalObject()) {
// TODO(verwaest): Also supporting the global object as receiver is a
// workaround for code that leaks the global object.
TRACE_HANDLER_STATS(isolate(), LoadIC_LoadGlobalDH);
smi_handler = LoadHandler::LoadGlobal(isolate());
Handle<WeakCell> cell =
isolate()->factory()->NewWeakCell(lookup->GetPropertyCell());
return LoadHandler::LoadFromPrototype(isolate(), map, holder,
smi_handler, cell);
}
smi_handler = LoadHandler::LoadNormal(isolate());
TRACE_HANDLER_STATS(isolate(), LoadIC_LoadNormalDH);
if (receiver_is_holder) return smi_handler;
TRACE_HANDLER_STATS(isolate(), LoadIC_LoadNormalFromPrototypeDH);
} else if (lookup->property_details().location() == kField) {
FieldIndex field = lookup->GetFieldIndex();
smi_handler = LoadHandler::LoadField(isolate(), field);
TRACE_HANDLER_STATS(isolate(), LoadIC_LoadFieldDH);
if (receiver_is_holder) return smi_handler;
TRACE_HANDLER_STATS(isolate(), LoadIC_LoadFieldFromPrototypeDH);
} else {
DCHECK_EQ(kDescriptor, lookup->property_details().location());
smi_handler =
LoadHandler::LoadConstant(isolate(), lookup->GetConstantIndex());
TRACE_HANDLER_STATS(isolate(), LoadIC_LoadConstantDH);
if (receiver_is_holder) return smi_handler;
TRACE_HANDLER_STATS(isolate(), LoadIC_LoadConstantFromPrototypeDH);
}
return LoadHandler::LoadFromPrototype(isolate(), map, holder,
smi_handler);
}
case LookupIterator::INTEGER_INDEXED_EXOTIC:
TRACE_HANDLER_STATS(isolate(), LoadIC_LoadIntegerIndexedExoticDH);
return LoadHandler::LoadNonExistent(isolate());
case LookupIterator::JSPROXY: {
Handle<JSProxy> holder_proxy = lookup->GetHolder<JSProxy>();
bool receiver_is_holder_proxy = receiver.is_identical_to(holder_proxy);
Handle<Smi> smi_handler = LoadHandler::LoadProxy(isolate());
if (receiver_is_holder_proxy) {
return smi_handler;
}
return LoadHandler::LoadFromPrototype(isolate(), map, holder_proxy,
smi_handler);
}
case LookupIterator::ACCESS_CHECK:
case LookupIterator::NOT_FOUND:
case LookupIterator::TRANSITION:
UNREACHABLE();
}
return Handle<Code>::null();
}
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 (std::isnan(value)) {
key = isolate->factory()->NaN_string();
} else {
int int_value = FastD2I(value);
if (value == int_value && Smi::IsValid(int_value)) {
key = handle(Smi::FromInt(int_value), isolate);
}
}
} else if (key->IsString()) {
key = isolate->factory()->InternalizeString(Handle<String>::cast(key));
}
return key;
}
bool KeyedLoadIC::CanChangeToAllowOutOfBounds(Handle<Map> receiver_map) {
Handle<Object> handler;
return nexus()->FindHandlerForMap(receiver_map).ToHandle(&handler) &&
LoadHandler::GetKeyedAccessLoadMode(*handler) == STANDARD_LOAD;
}
void KeyedLoadIC::UpdateLoadElement(Handle<HeapObject> receiver,
KeyedAccessLoadMode load_mode) {
Handle<Map> receiver_map(receiver->map(), isolate());
DCHECK(receiver_map->instance_type() != JS_VALUE_TYPE); // Checked by caller.
MapHandles target_receiver_maps;
TargetMaps(&target_receiver_maps);
if (target_receiver_maps.empty()) {
Handle<Object> handler = LoadElementHandler(receiver_map, load_mode);
return ConfigureVectorState(Handle<Name>(), receiver_map, handler);
}
for (Handle<Map> map : target_receiver_maps) {
if (map.is_null()) continue;
if (map->instance_type() == JS_VALUE_TYPE) {
TRACE_GENERIC_IC("JSValue");
return;
}
if (map->instance_type() == JS_PROXY_TYPE) {
TRACE_GENERIC_IC("JSProxy");
return;
}
}
// 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.
if (state() == MONOMORPHIC && !receiver->IsString() &&
!receiver->IsJSProxy() &&
IsMoreGeneralElementsKindTransition(
target_receiver_maps.at(0)->elements_kind(),
Handle<JSObject>::cast(receiver)->GetElementsKind())) {
Handle<Object> handler = LoadElementHandler(receiver_map, load_mode);
return ConfigureVectorState(Handle<Name>(), receiver_map, handler);
}
DCHECK(state() != GENERIC);
// Determine the list of receiver maps that this call site has seen,
// adding the map that was just encountered.
if (!AddOneReceiverMapIfMissing(&target_receiver_maps, receiver_map)) {
// If the {receiver_map} previously had a handler that didn't handle
// out-of-bounds access, but can generally handle it, we can just go
// on and update the handler appropriately below.
if (load_mode != LOAD_IGNORE_OUT_OF_BOUNDS ||
!CanChangeToAllowOutOfBounds(receiver_map)) {
// If the miss wasn't due to an unseen map, a polymorphic stub
// won't help, use the generic stub.
TRACE_GENERIC_IC("same map added twice");
return;
}
}
// If the maximum number of receiver maps has been exceeded, use the generic
// version of the IC.
if (target_receiver_maps.size() > kMaxKeyedPolymorphism) {
TRACE_GENERIC_IC("max polymorph exceeded");
return;
}
ObjectHandles handlers;
handlers.reserve(target_receiver_maps.size());
LoadElementPolymorphicHandlers(&target_receiver_maps, &handlers, load_mode);
DCHECK_LE(1, target_receiver_maps.size());
if (target_receiver_maps.size() == 1) {
ConfigureVectorState(Handle<Name>(), target_receiver_maps[0], handlers[0]);
} else {
ConfigureVectorState(Handle<Name>(), target_receiver_maps, &handlers);
}
}
Handle<Object> KeyedLoadIC::LoadElementHandler(Handle<Map> receiver_map,
KeyedAccessLoadMode load_mode) {
if (receiver_map->has_indexed_interceptor() &&
!receiver_map->GetIndexedInterceptor()->getter()->IsUndefined(
isolate()) &&
!receiver_map->GetIndexedInterceptor()->non_masking()) {
TRACE_HANDLER_STATS(isolate(), KeyedLoadIC_LoadIndexedInterceptorStub);
return LoadIndexedInterceptorStub(isolate()).GetCode();
}
InstanceType instance_type = receiver_map->instance_type();
if (instance_type < FIRST_NONSTRING_TYPE) {
TRACE_HANDLER_STATS(isolate(), KeyedLoadIC_LoadIndexedStringDH);
return LoadHandler::LoadIndexedString(isolate(), load_mode);
}
if (instance_type < FIRST_JS_RECEIVER_TYPE) {
TRACE_HANDLER_STATS(isolate(), KeyedLoadIC_SlowStub);
return BUILTIN_CODE(isolate(), KeyedLoadIC_Slow);
}
if (instance_type == JS_PROXY_TYPE) {
return LoadHandler::LoadProxy(isolate());
}
ElementsKind elements_kind = receiver_map->elements_kind();
if (IsSloppyArgumentsElementsKind(elements_kind)) {
TRACE_HANDLER_STATS(isolate(), KeyedLoadIC_KeyedLoadSloppyArgumentsStub);
return KeyedLoadSloppyArgumentsStub(isolate()).GetCode();
}
bool is_js_array = instance_type == JS_ARRAY_TYPE;
if (elements_kind == DICTIONARY_ELEMENTS) {
TRACE_HANDLER_STATS(isolate(), KeyedLoadIC_LoadElementDH);
return LoadHandler::LoadElement(isolate(), elements_kind, false,
is_js_array, load_mode);
}
DCHECK(IsFastElementsKind(elements_kind) ||
IsFixedTypedArrayElementsKind(elements_kind));
// TODO(jkummerow): Use IsHoleyOrDictionaryElementsKind(elements_kind).
bool convert_hole_to_undefined =
is_js_array && elements_kind == HOLEY_ELEMENTS &&
*receiver_map ==
isolate()->raw_native_context()->GetInitialJSArrayMap(elements_kind);
TRACE_HANDLER_STATS(isolate(), KeyedLoadIC_LoadElementDH);
return LoadHandler::LoadElement(isolate(), elements_kind,
convert_hole_to_undefined, is_js_array,
load_mode);
}
void KeyedLoadIC::LoadElementPolymorphicHandlers(
MapHandles* receiver_maps, ObjectHandles* handlers,
KeyedAccessLoadMode load_mode) {
// Filter out deprecated maps to ensure their instances get migrated.
receiver_maps->erase(
std::remove_if(
receiver_maps->begin(), receiver_maps->end(),
[](const Handle<Map>& map) { return map->is_deprecated(); }),
receiver_maps->end());
for (Handle<Map> receiver_map : *receiver_maps) {
// Mark all stable receiver maps that have elements kind transition map
// among receiver_maps as unstable because the optimizing compilers may
// generate an elements kind transition for this kind of receivers.
if (receiver_map->is_stable()) {
Map* tmap = receiver_map->FindElementsKindTransitionedMap(*receiver_maps);
if (tmap != nullptr) {
receiver_map->NotifyLeafMapLayoutChange();
}
}
handlers->push_back(LoadElementHandler(receiver_map, load_mode));
}
}
namespace {
bool IsOutOfBoundsAccess(Handle<Object> receiver, uint32_t index) {
uint32_t length = 0;
if (receiver->IsJSArray()) {
JSArray::cast(*receiver)->length()->ToArrayLength(&length);
} else if (receiver->IsString()) {
length = String::cast(*receiver)->length();
} else if (receiver->IsJSObject()) {
length = JSObject::cast(*receiver)->elements()->length();
} else {
return false;
}
return index >= length;
}
KeyedAccessLoadMode GetLoadMode(Handle<Object> receiver, uint32_t index) {
if (IsOutOfBoundsAccess(receiver, index)) {
if (receiver->IsJSTypedArray()) {
// For JSTypedArray we never lookup elements in the prototype chain.
return LOAD_IGNORE_OUT_OF_BOUNDS;
}
// For other {receiver}s we need to check the "no elements" protector.
Isolate* isolate = Handle<HeapObject>::cast(receiver)->GetIsolate();
if (isolate->IsNoElementsProtectorIntact()) {
if (receiver->IsString()) {
// ToObject(receiver) will have the initial String.prototype.
return LOAD_IGNORE_OUT_OF_BOUNDS;
}
if (receiver->IsJSObject()) {
// For other JSObjects (including JSArrays) we can only continue if
// the {receiver}s prototype is either the initial Object.prototype
// or the initial Array.prototype, which are both guarded by the
// "no elements" protector checked above.
Handle<Object> receiver_prototype(
JSObject::cast(*receiver)->map()->prototype(), isolate);
if (isolate->IsInAnyContext(*receiver_prototype,
Context::INITIAL_ARRAY_PROTOTYPE_INDEX) ||
isolate->IsInAnyContext(*receiver_prototype,
Context::INITIAL_OBJECT_PROTOTYPE_INDEX)) {
return LOAD_IGNORE_OUT_OF_BOUNDS;
}
}
}
}
return STANDARD_LOAD;
}
} // namespace
MaybeHandle<Object> KeyedLoadIC::Load(Handle<Object> object,
Handle<Object> key) {
if (MigrateDeprecated(object)) {
Handle<Object> result;
ASSIGN_RETURN_ON_EXCEPTION(
isolate(), result, Runtime::GetObjectProperty(isolate(), object, key),
Object);
return result;
}
Handle<Object> load_handle;
// Check for non-string values that can be converted into an
// internalized string directly or is representable as a smi.
key = TryConvertKey(key, isolate());
uint32_t index;
if ((key->IsInternalizedString() &&
!String::cast(*key)->AsArrayIndex(&index)) ||
key->IsSymbol()) {
ASSIGN_RETURN_ON_EXCEPTION(isolate(), load_handle,
LoadIC::Load(object, Handle<Name>::cast(key)),
Object);
} else if (FLAG_use_ic && !object->IsAccessCheckNeeded() &&
!object->IsJSValue()) {
if ((object->IsJSReceiver() || object->IsString()) &&
key->ToArrayIndex(&index)) {
KeyedAccessLoadMode load_mode = GetLoadMode(object, index);
UpdateLoadElement(Handle<HeapObject>::cast(object), load_mode);
if (is_vector_set()) {
TRACE_IC("LoadIC", key);
}
}
}
if (vector_needs_update()) {
ConfigureVectorState(MEGAMORPHIC, key);
TRACE_IC("LoadIC", key);
}
if (!load_handle.is_null()) return load_handle;
Handle<Object> result;
ASSIGN_RETURN_ON_EXCEPTION(isolate(), result,
Runtime::GetObjectProperty(isolate(), object, key),
Object);
return result;
}
bool StoreIC::LookupForWrite(LookupIterator* it, Handle<Object> value,
JSReceiver::StoreFromKeyed store_mode) {
// Disable ICs for non-JSObjects for now.
Handle<Object> object = it->GetReceiver();
if (object->IsJSProxy()) return true;
if (!object->IsJSObject()) return false;
Handle<JSObject> receiver = Handle<JSObject>::cast(object);
DCHECK(!receiver->map()->is_deprecated());
for (; it->IsFound(); it->Next()) {
switch (it->state()) {
case LookupIterator::NOT_FOUND:
case LookupIterator::TRANSITION:
UNREACHABLE();
case LookupIterator::JSPROXY:
return true;
case LookupIterator::INTERCEPTOR: {
Handle<JSObject> holder = it->GetHolder<JSObject>();
InterceptorInfo* info = holder->GetNamedInterceptor();
if (it->HolderIsReceiverOrHiddenPrototype()) {
return !info->non_masking() && receiver.is_identical_to(holder) &&
!info->setter()->IsUndefined(it->isolate());
} else if (!info->getter()->IsUndefined(it->isolate()) ||
!info->query()->IsUndefined(it->isolate())) {
return false;
}
break;
}
case LookupIterator::ACCESS_CHECK:
if (it->GetHolder<JSObject>()->IsAccessCheckNeeded()) return false;
break;
case LookupIterator::ACCESSOR:
return !it->IsReadOnly();
case LookupIterator::INTEGER_INDEXED_EXOTIC:
return false;
case LookupIterator::DATA: {
if (it->IsReadOnly()) return false;
Handle<JSObject> holder = it->GetHolder<JSObject>();
if (receiver.is_identical_to(holder)) {
it->PrepareForDataProperty(value);
// The previous receiver map might just have been deprecated,
// so reload it.
update_receiver_map(receiver);
return true;
}
// Receiver != holder.
if (receiver->IsJSGlobalProxy()) {
PrototypeIterator iter(it->isolate(), receiver);
return it->GetHolder<Object>().is_identical_to(
PrototypeIterator::GetCurrent(iter));
}
if (it->HolderIsReceiverOrHiddenPrototype()) return false;
if (it->ExtendingNonExtensible(receiver)) return false;
created_new_transition_ = it->PrepareTransitionToDataProperty(
receiver, value, NONE, store_mode);
return it->IsCacheableTransition();
}
}
}
receiver = it->GetStoreTarget();
if (it->ExtendingNonExtensible(receiver)) return false;
created_new_transition_ =
it->PrepareTransitionToDataProperty(receiver, value, NONE, store_mode);
return it->IsCacheableTransition();
}
MaybeHandle<Object> StoreGlobalIC::Store(Handle<Name> name,
Handle<Object> value) {
DCHECK(name->IsString());
// Look up in script context table.
Handle<String> str_name = Handle<String>::cast(name);
Handle<JSGlobalObject> global = isolate()->global_object();
Handle<ScriptContextTable> script_contexts(
global->native_context()->script_context_table());
ScriptContextTable::LookupResult lookup_result;
if (ScriptContextTable::Lookup(script_contexts, str_name, &lookup_result)) {
Handle<Context> script_context = ScriptContextTable::GetContext(
script_contexts, lookup_result.context_index);
if (lookup_result.mode == CONST) {
return TypeError(MessageTemplate::kConstAssign, global, name);
}
Handle<Object> previous_value =
FixedArray::get(*script_context, lookup_result.slot_index, isolate());
if (previous_value->IsTheHole(isolate())) {
// Do not install stubs and stay pre-monomorphic for
// uninitialized accesses.
return ReferenceError(name);
}
if (FLAG_use_ic) {
StoreGlobalICNexus* nexus = casted_nexus<StoreGlobalICNexus>();
if (nexus->ConfigureLexicalVarMode(lookup_result.context_index,
lookup_result.slot_index)) {
TRACE_HANDLER_STATS(isolate(), StoreGlobalIC_StoreScriptContextField);
} else {
// Given combination of indices can't be encoded, so use slow stub.
TRACE_HANDLER_STATS(isolate(), StoreGlobalIC_SlowStub);
PatchCache(name, slow_stub());
}
TRACE_IC("StoreGlobalIC", name);
}
script_context->set(lookup_result.slot_index, *value);
return value;
}
return StoreIC::Store(global, name, value);
}
MaybeHandle<Object> StoreIC::Store(Handle<Object> object, Handle<Name> name,
Handle<Object> value,
JSReceiver::StoreFromKeyed store_mode) {
// TODO(verwaest): Let SetProperty do the migration, since storing a property
// might deprecate the current map again, if value does not fit.
if (MigrateDeprecated(object)) {
Handle<Object> result;
ASSIGN_RETURN_ON_EXCEPTION(
isolate(), result,
Object::SetProperty(object, name, value, language_mode()), Object);
return result;
}
// 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->IsNullOrUndefined(isolate())) {
if (FLAG_use_ic && state() != PREMONOMORPHIC) {
// Ensure the IC state progresses.
TRACE_HANDLER_STATS(isolate(), StoreIC_NonReceiver);
update_receiver_map(object);
PatchCache(name, slow_stub());
TRACE_IC("StoreIC", name);
}
return TypeError(MessageTemplate::kNonObjectPropertyStore, object, name);
}
if (state() != UNINITIALIZED) {
JSObject::MakePrototypesFast(object, kStartAtPrototype, isolate());
}
MaybeHandle<Object> cached_handler;
Handle<Map> transition_map;
if (object->IsJSReceiver()) {
name = isolate()->factory()->InternalizeName(name);
TransitionsAccessor transitions(receiver_map());
Object* maybe_handler = transitions.SearchHandler(*name, &transition_map);
if (maybe_handler != nullptr) {
cached_handler = MaybeHandle<Object>(maybe_handler, isolate());
}
}
LookupIterator it = LookupIterator::ForTransitionHandler(
isolate(), object, name, value, cached_handler, transition_map);
if (FLAG_use_ic) UpdateCaches(&it, value, store_mode, cached_handler);
MAYBE_RETURN_NULL(
Object::SetProperty(&it, value, language_mode(), store_mode));
return value;
}
void StoreIC::UpdateCaches(LookupIterator* lookup, Handle<Object> value,
JSReceiver::StoreFromKeyed store_mode,
MaybeHandle<Object> cached_handler) {
if (state() == UNINITIALIZED && !IsStoreGlobalIC()) {
// This is the first time we execute this inline cache. Set the target to
// the pre monomorphic stub to delay setting the monomorphic state.
TRACE_HANDLER_STATS(isolate(), StoreIC_Premonomorphic);
ConfigureVectorState(PREMONOMORPHIC, Handle<Object>());
TRACE_IC("StoreIC", lookup->name());
return;
}
Handle<Object> handler;
if (!cached_handler.is_null()) {
handler = cached_handler.ToHandleChecked();
} else if (LookupForWrite(lookup, value, store_mode)) {
if (IsStoreGlobalIC()) {
if (lookup->state() == LookupIterator::DATA &&
lookup->GetReceiver().is_identical_to(lookup->GetHolder<Object>())) {
DCHECK(lookup->GetReceiver()->IsJSGlobalObject());
// Now update the cell in the feedback vector.
StoreGlobalICNexus* nexus = casted_nexus<StoreGlobalICNexus>();
nexus->ConfigurePropertyCellMode(lookup->GetPropertyCell());
TRACE_IC("StoreGlobalIC", lookup->name());
return;
}
}
if (created_new_transition_) {
// The first time a transition is performed, there's a good chance that
// it won't be taken again, so don't bother creating a handler.
TRACE_GENERIC_IC("new transition");
TRACE_IC("StoreIC", lookup->name());
return;
}
handler = ComputeHandler(lookup);
} else {
TRACE_GENERIC_IC("LookupForWrite said 'false'");
handler = slow_stub();
}
PatchCache(lookup->name(), handler);
TRACE_IC("StoreIC", lookup->name());
}
Handle<Object> StoreIC::ComputeHandler(LookupIterator* lookup) {
switch (lookup->state()) {
case LookupIterator::TRANSITION: {
Handle<JSObject> holder = lookup->GetHolder<JSObject>();
Handle<JSObject> store_target = lookup->GetStoreTarget();
if (store_target->IsJSGlobalObject()) {
TRACE_HANDLER_STATS(isolate(), StoreIC_StoreGlobalTransitionDH);
if (receiver_map()->IsJSGlobalObject()) {
DCHECK(IsStoreGlobalIC());
DCHECK_EQ(*lookup->GetReceiver(), *holder);
DCHECK_EQ(*store_target, *holder);
return StoreHandler::StoreGlobal(isolate(),
lookup->transition_cell());
}
Handle<Smi> smi_handler = StoreHandler::StoreGlobalProxy(isolate());
Handle<WeakCell> cell =
isolate()->factory()->NewWeakCell(lookup->transition_cell());
Handle<Object> handler = StoreHandler::StoreThroughPrototype(
isolate(), receiver_map(), store_target, smi_handler, cell);
return handler;
}
// Currently not handled by CompileStoreTransition.
if (!holder->HasFastProperties()) {
TRACE_GENERIC_IC("transition from slow");
TRACE_HANDLER_STATS(isolate(), StoreIC_SlowStub);
return slow_stub();
}
DCHECK(lookup->IsCacheableTransition());
Handle<Map> transition = lookup->transition_map();
Handle<Smi> smi_handler;
if (transition->is_dictionary_map()) {
TRACE_HANDLER_STATS(isolate(), StoreIC_StoreNormalDH);
smi_handler = StoreHandler::StoreNormal(isolate());
} else {
TRACE_HANDLER_STATS(isolate(), StoreIC_StoreTransitionDH);
smi_handler = StoreHandler::StoreTransition(isolate(), transition);
}
Handle<WeakCell> cell = Map::WeakCellForMap(transition);
Handle<Object> handler = StoreHandler::StoreThroughPrototype(
isolate(), receiver_map(), holder, smi_handler, cell);
TransitionsAccessor(receiver_map())
.UpdateHandler(*lookup->name(), *handler);
return handler;
}
case LookupIterator::INTERCEPTOR: {
Handle<JSObject> holder = lookup->GetHolder<JSObject>();
USE(holder);
DCHECK(!holder->GetNamedInterceptor()->setter()->IsUndefined(isolate()));
TRACE_HANDLER_STATS(isolate(), StoreIC_StoreInterceptorStub);
StoreInterceptorStub stub(isolate());
return stub.GetCode();
}
case LookupIterator::ACCESSOR: {
// This is currently guaranteed by checks in StoreIC::Store.
Handle<JSObject> receiver = Handle<JSObject>::cast(lookup->GetReceiver());
Handle<JSObject> holder = lookup->GetHolder<JSObject>();
DCHECK(!receiver->IsAccessCheckNeeded() || lookup->name()->IsPrivate());
if (!holder->HasFastProperties()) {
TRACE_GENERIC_IC("accessor on slow map");
TRACE_HANDLER_STATS(isolate(), StoreIC_SlowStub);
return slow_stub();
}
Handle<Object> accessors = lookup->GetAccessors();
if (accessors->IsAccessorInfo()) {
Handle<AccessorInfo> info = Handle<AccessorInfo>::cast(accessors);
if (v8::ToCData<Address>(info->setter()) == nullptr) {
TRACE_GENERIC_IC("setter == nullptr");
TRACE_HANDLER_STATS(isolate(), StoreIC_SlowStub);
return slow_stub();
}
if (AccessorInfo::cast(*accessors)->is_special_data_property() &&
!lookup->HolderIsReceiverOrHiddenPrototype()) {
TRACE_GENERIC_IC("special data property in prototype chain");
TRACE_HANDLER_STATS(isolate(), StoreIC_SlowStub);
return slow_stub();
}
if (!AccessorInfo::IsCompatibleReceiverMap(isolate(), info,
receiver_map())) {
TRACE_GENERIC_IC("incompatible receiver type");
TRACE_HANDLER_STATS(isolate(), StoreIC_SlowStub);
return slow_stub();
}
Handle<Smi> smi_handler = StoreHandler::StoreNativeDataProperty(
isolate(), lookup->GetAccessorIndex());
TRACE_HANDLER_STATS(isolate(), StoreIC_StoreNativeDataPropertyDH);
if (receiver.is_identical_to(holder)) return smi_handler;
TRACE_HANDLER_STATS(isolate(),
StoreIC_StoreNativeDataPropertyOnPrototypeDH);
return StoreHandler::StoreThroughPrototype(isolate(), receiver_map(),
holder, smi_handler);
} else if (accessors->IsAccessorPair()) {
Handle<Object> setter(Handle<AccessorPair>::cast(accessors)->setter(),
isolate());
if (!setter->IsJSFunction() && !setter->IsFunctionTemplateInfo()) {
TRACE_GENERIC_IC("setter not a function");
TRACE_HANDLER_STATS(isolate(), StoreIC_SlowStub);
return slow_stub();
}
CallOptimization call_optimization(setter);
if (call_optimization.is_simple_api_call()) {
if (call_optimization.IsCompatibleReceiver(receiver, holder)) {
CallOptimization::HolderLookup holder_lookup;
call_optimization.LookupHolderOfExpectedType(receiver_map(),
&holder_lookup);
Handle<Smi> smi_handler = StoreHandler::StoreApiSetter(
isolate(),
holder_lookup == CallOptimization::kHolderIsReceiver);
Handle<Context> context(
call_optimization.GetAccessorContext(holder->map()));
Handle<WeakCell> context_cell =
isolate()->factory()->NewWeakCell(context);
Handle<WeakCell> data_cell = isolate()->factory()->NewWeakCell(
call_optimization.api_call_info());
TRACE_HANDLER_STATS(isolate(), StoreIC_StoreApiSetterOnPrototypeDH);
return StoreHandler::StoreThroughPrototype(
isolate(), receiver_map(), holder, smi_handler, data_cell,
context_cell);
}
TRACE_GENERIC_IC("incompatible receiver");
TRACE_HANDLER_STATS(isolate(), StoreIC_SlowStub);
return slow_stub();
} else if (setter->IsFunctionTemplateInfo()) {
TRACE_GENERIC_IC("setter non-simple template");
TRACE_HANDLER_STATS(isolate(), StoreIC_SlowStub);
return slow_stub();
}
Handle<Smi> smi_handler =
StoreHandler::StoreAccessor(isolate(), lookup->GetAccessorIndex());
TRACE_HANDLER_STATS(isolate(), StoreIC_StoreAccessorDH);
if (receiver.is_identical_to(holder)) return smi_handler;
TRACE_HANDLER_STATS(isolate(), StoreIC_StoreAccessorOnPrototypeDH);
return StoreHandler::StoreThroughPrototype(isolate(), receiver_map(),
holder, smi_handler);
}
TRACE_HANDLER_STATS(isolate(), StoreIC_SlowStub);
return slow_stub();
}
case LookupIterator::DATA: {
// This is currently guaranteed by checks in StoreIC::Store.
Handle<JSObject> receiver = Handle<JSObject>::cast(lookup->GetReceiver());
USE(receiver);
Handle<JSObject> holder = lookup->GetHolder<JSObject>();
DCHECK(!receiver->IsAccessCheckNeeded() || lookup->name()->IsPrivate());
DCHECK_EQ(kData, lookup->property_details().kind());
if (lookup->is_dictionary_holder()) {
if (holder->IsJSGlobalObject()) {
TRACE_HANDLER_STATS(isolate(), StoreIC_StoreGlobalDH);
return StoreHandler::StoreGlobal(isolate(),
lookup->GetPropertyCell());
}
TRACE_HANDLER_STATS(isolate(), StoreIC_StoreNormalDH);
DCHECK(holder.is_identical_to(receiver));
return StoreHandler::StoreNormal(isolate());
}
// -------------- Fields --------------
if (lookup->property_details().location() == kField) {
TRACE_HANDLER_STATS(isolate(), StoreIC_StoreFieldDH);
int descriptor = lookup->GetFieldDescriptorIndex();
FieldIndex index = lookup->GetFieldIndex();
PropertyConstness constness = lookup->constness();
if (constness == kConst && IsStoreOwnICKind(nexus()->kind())) {
// StoreOwnICs are used for initializing object literals therefore
// we must store the value unconditionally even to kConst fields.
constness = kMutable;
}
return StoreHandler::StoreField(isolate(), descriptor, index, constness,
lookup->representation());
}
// -------------- Constant properties --------------
DCHECK_EQ(kDescriptor, lookup->property_details().location());
TRACE_GENERIC_IC("constant property");
TRACE_HANDLER_STATS(isolate(), StoreIC_SlowStub);
return slow_stub();
}
case LookupIterator::JSPROXY: {
Handle<JSReceiver> receiver =
Handle<JSReceiver>::cast(lookup->GetReceiver());
Handle<JSProxy> holder = lookup->GetHolder<JSProxy>();
return StoreHandler::StoreProxy(isolate(), receiver_map(), holder,
receiver);
}
case LookupIterator::INTEGER_INDEXED_EXOTIC:
case LookupIterator::ACCESS_CHECK:
case LookupIterator::NOT_FOUND:
UNREACHABLE();
}
return Handle<Code>::null();
}
void KeyedStoreIC::UpdateStoreElement(Handle<Map> receiver_map,
KeyedAccessStoreMode store_mode) {
MapHandles target_receiver_maps;
TargetMaps(&target_receiver_maps);
if (target_receiver_maps.empty()) {
Handle<Map> monomorphic_map =
ComputeTransitionedMap(receiver_map, store_mode);
store_mode = GetNonTransitioningStoreMode(store_mode);
Handle<Object> handler = StoreElementHandler(monomorphic_map, store_mode);
return ConfigureVectorState(Handle<Name>(), monomorphic_map, handler);
}
for (Handle<Map> map : target_receiver_maps) {
if (!map.is_null() && map->instance_type() == JS_VALUE_TYPE) {
TRACE_GENERIC_IC("JSValue");
return;
}
}
// There are several special cases where an IC that is MONOMORPHIC can still
// transition to a different GetNonTransitioningStoreMode IC that handles a
// superset of the original IC. Handle those here if the receiver map hasn't
// changed or it has transitioned to a more general kind.
KeyedAccessStoreMode old_store_mode;
old_store_mode = GetKeyedAccessStoreMode();
Handle<Map> previous_receiver_map = target_receiver_maps.at(0);
if (state() == MONOMORPHIC) {
Handle<Map> transitioned_receiver_map = receiver_map;
if (IsTransitionStoreMode(store_mode)) {
transitioned_receiver_map =
ComputeTransitionedMap(receiver_map, store_mode);
}
if ((receiver_map.is_identical_to(previous_receiver_map) &&
IsTransitionStoreMode(store_mode)) ||
IsTransitionOfMonomorphicTarget(*previous_receiver_map,
*transitioned_receiver_map)) {
// If the "old" and "new" maps are in the same elements map family, or
// if they at least come from the same origin for a transitioning store,
// stay MONOMORPHIC and use the map for the most generic ElementsKind.
store_mode = GetNonTransitioningStoreMode(store_mode);
Handle<Object> handler =
StoreElementHandler(transitioned_receiver_map, store_mode);
ConfigureVectorState(Handle<Name>(), transitioned_receiver_map, handler);
return;
}
if (receiver_map.is_identical_to(previous_receiver_map) &&
old_store_mode == STANDARD_STORE &&
(store_mode == STORE_AND_GROW_NO_TRANSITION ||
store_mode == STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS ||
store_mode == STORE_NO_TRANSITION_HANDLE_COW)) {
// A "normal" IC that handles stores can switch to a version that can
// grow at the end of the array, handle OOB accesses or copy COW arrays
// and still stay MONOMORPHIC.
Handle<Object> handler = StoreElementHandler(receiver_map, store_mode);
return ConfigureVectorState(Handle<Name>(), receiver_map, handler);
}
}
DCHECK(state() != GENERIC);
bool map_added =
AddOneReceiverMapIfMissing(&target_receiver_maps, receiver_map);
if (IsTransitionStoreMode(store_mode)) {
Handle<Map> transitioned_receiver_map =
ComputeTransitionedMap(receiver_map, store_mode);
map_added |= AddOneReceiverMapIfMissing(&target_receiver_maps,
transitioned_receiver_map);
}
if (!map_added) {
// If the miss wasn't due to an unseen map, a polymorphic stub
// won't help, use the megamorphic stub which can handle everything.
TRACE_GENERIC_IC("same map added twice");
return;
}
// If the maximum number of receiver maps has been exceeded, use the
// megamorphic version of the IC.
if (target_receiver_maps.size() > kMaxKeyedPolymorphism) return;
// Make sure all polymorphic handlers have the same store mode, otherwise the
// megamorphic stub must be used.
store_mode = GetNonTransitioningStoreMode(store_mode);
if (old_store_mode != STANDARD_STORE) {
if (store_mode == STANDARD_STORE) {
store_mode = old_store_mode;
} else if (store_mode != old_store_mode) {
TRACE_GENERIC_IC("store mode mismatch");
return;
}
}
// If the store mode isn't the standard mode, make sure that all polymorphic
// receivers are either external arrays, or all "normal" arrays. Otherwise,
// use the megamorphic stub.
if (store_mode != STANDARD_STORE) {
size_t external_arrays = 0;
for (Handle<Map> map : target_receiver_maps) {
if (map->has_fixed_typed_array_elements()) {
external_arrays++;
}
}
if (external_arrays != 0 &&
external_arrays != target_receiver_maps.size()) {
TRACE_GENERIC_IC("unsupported combination of external and normal arrays");
return;
}
}
ObjectHandles handlers;
handlers.reserve(target_receiver_maps.size());
StoreElementPolymorphicHandlers(&target_receiver_maps, &handlers, store_mode);
if (target_receiver_maps.size() == 0) {
ConfigureVectorState(PREMONOMORPHIC, Handle<Name>());
} else if (target_receiver_maps.size() == 1) {
ConfigureVectorState(Handle<Name>(), target_receiver_maps[0], handlers[0]);
} else {
ConfigureVectorState(Handle<Name>(), target_receiver_maps, &handlers);
}
}
Handle<Map> KeyedStoreIC::ComputeTransitionedMap(
Handle<Map> map, KeyedAccessStoreMode store_mode) {
switch (store_mode) {
case STORE_TRANSITION_TO_OBJECT:
case STORE_AND_GROW_TRANSITION_TO_OBJECT: {
ElementsKind kind = IsHoleyElementsKind(map->elements_kind())
? HOLEY_ELEMENTS
: PACKED_ELEMENTS;
return Map::TransitionElementsTo(map, kind);
}
case STORE_TRANSITION_TO_DOUBLE:
case STORE_AND_GROW_TRANSITION_TO_DOUBLE: {
ElementsKind kind = IsHoleyElementsKind(map->elements_kind())
? HOLEY_DOUBLE_ELEMENTS
: PACKED_DOUBLE_ELEMENTS;
return Map::TransitionElementsTo(map, kind);
}
case STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS:
DCHECK(map->has_fixed_typed_array_elements());
// Fall through
case STORE_NO_TRANSITION_HANDLE_COW:
case STANDARD_STORE:
case STORE_AND_GROW_NO_TRANSITION:
return map;
}
UNREACHABLE();
}
Handle<Object> KeyedStoreIC::StoreElementHandler(
Handle<Map> receiver_map, KeyedAccessStoreMode store_mode) {
DCHECK(store_mode == STANDARD_STORE ||
store_mode == STORE_AND_GROW_NO_TRANSITION ||
store_mode == STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS ||
store_mode == STORE_NO_TRANSITION_HANDLE_COW);
DCHECK(!receiver_map->DictionaryElementsInPrototypeChainOnly());
if (receiver_map->IsJSProxyMap()) {
return StoreHandler::StoreProxy(isolate());
}
// TODO(ishell): move to StoreHandler::StoreElement().
ElementsKind elements_kind = receiver_map->elements_kind();
bool is_jsarray = receiver_map->instance_type() == JS_ARRAY_TYPE;
Handle<Code> stub;
if (receiver_map->has_sloppy_arguments_elements()) {
TRACE_HANDLER_STATS(isolate(), KeyedStoreIC_KeyedStoreSloppyArgumentsStub);
stub = KeyedStoreSloppyArgumentsStub(isolate(), store_mode).GetCode();
} else if (receiver_map->has_fast_elements() ||
receiver_map->has_fixed_typed_array_elements()) {
TRACE_HANDLER_STATS(isolate(), KeyedStoreIC_StoreFastElementStub);
stub =
StoreFastElementStub(isolate(), is_jsarray, elements_kind, store_mode)
.GetCode();
if (receiver_map->has_fixed_typed_array_elements()) return stub;
} else {
TRACE_HANDLER_STATS(isolate(), KeyedStoreIC_StoreElementStub);
DCHECK_EQ(DICTIONARY_ELEMENTS, elements_kind);
stub = StoreSlowElementStub(isolate(), store_mode).GetCode();
}
Handle<Object> validity_cell =
Map::GetOrCreatePrototypeChainValidityCell(receiver_map, isolate());
if (validity_cell.is_null()) return stub;
Handle<StoreHandler> handler = isolate()->factory()->NewStoreHandler(0);
handler->set_validity_cell(*validity_cell);
handler->set_smi_handler(*stub);
return handler;
}
void KeyedStoreIC::StoreElementPolymorphicHandlers(
MapHandles* receiver_maps, ObjectHandles* handlers,
KeyedAccessStoreMode store_mode) {
DCHECK(store_mode == STANDARD_STORE ||
store_mode == STORE_AND_GROW_NO_TRANSITION ||
store_mode == STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS ||
store_mode == STORE_NO_TRANSITION_HANDLE_COW);
// Filter out deprecated maps to ensure their instances get migrated.
receiver_maps->erase(
std::remove_if(
receiver_maps->begin(), receiver_maps->end(),
[](const Handle<Map>& map) { return map->is_deprecated(); }),
receiver_maps->end());
for (Handle<Map> receiver_map : *receiver_maps) {
Handle<Object> handler;
Handle<Map> transition;
if (receiver_map->instance_type() < FIRST_JS_RECEIVER_TYPE ||
receiver_map->DictionaryElementsInPrototypeChainOnly()) {
// TODO(mvstanton): Consider embedding store_mode in the state of the slow
// keyed store ic for uniformity.
TRACE_HANDLER_STATS(isolate(), KeyedStoreIC_SlowStub);
handler = BUILTIN_CODE(isolate(), KeyedStoreIC_Slow);
} else {
{
Map* tmap =
receiver_map->FindElementsKindTransitionedMap(*receiver_maps);
if (tmap != nullptr) {
if (receiver_map->is_stable()) {
receiver_map->NotifyLeafMapLayoutChange();
}
transition = handle(tmap);
}
}
// TODO(mvstanton): The code below is doing pessimistic elements
// transitions. I would like to stop doing that and rely on Allocation
// Site Tracking to do a better job of ensuring the data types are what
// they need to be. Not all the elements are in place yet, pessimistic
// elements transitions are still important for performance.
if (!transition.is_null()) {
TRACE_HANDLER_STATS(isolate(),
KeyedStoreIC_ElementsTransitionAndStoreStub);
handler = StoreHandler::StoreElementTransition(isolate(), receiver_map,
transition, store_mode);
} else {
handler = StoreElementHandler(receiver_map, store_mode);
}
}
DCHECK(!handler.is_null());
handlers->push_back(handler);
}
}
static KeyedAccessStoreMode GetStoreMode(Handle<JSObject> receiver,
uint32_t index, Handle<Object> value) {
bool oob_access = IsOutOfBoundsAccess(receiver, index);
// Don't consider this a growing store if the store would send the receiver to
// dictionary mode.
bool allow_growth = receiver->IsJSArray() && oob_access &&
!receiver->WouldConvertToSlowElements(index);
if (allow_growth) {
// Handle growing array in stub if necessary.
if (receiver->HasSmiElements()) {
if (value->IsHeapNumber()) {
return STORE_AND_GROW_TRANSITION_TO_DOUBLE;
}
if (value->IsHeapObject()) {
return STORE_AND_GROW_TRANSITION_TO_OBJECT;
}
} else if (receiver->HasDoubleElements()) {
if (!value->IsSmi() && !value->IsHeapNumber()) {
return STORE_AND_GROW_TRANSITION_TO_OBJECT;
}
}
return STORE_AND_GROW_NO_TRANSITION;
} else {
// Handle only in-bounds elements accesses.
if (receiver->HasSmiElements()) {
if (value->IsHeapNumber()) {
return STORE_TRANSITION_TO_DOUBLE;
} else if (value->IsHeapObject()) {
return STORE_TRANSITION_TO_OBJECT;
}
} else if (receiver->HasDoubleElements()) {
if (!value->IsSmi() && !value->IsHeapNumber()) {
return STORE_TRANSITION_TO_OBJECT;
}
}
if (!FLAG_trace_external_array_abuse &&
receiver->map()->has_fixed_typed_array_elements() && oob_access) {
return STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS;
}
Heap* heap = receiver->GetHeap();
if (receiver->elements()->map() == heap->fixed_cow_array_map()) {
return STORE_NO_TRANSITION_HANDLE_COW;
} else {
return STANDARD_STORE;
}
}
}
MaybeHandle<Object> KeyedStoreIC::Store(Handle<Object> object,
Handle<Object> key,
Handle<Object> value) {
// TODO(verwaest): Let SetProperty do the migration, since storing a property
// might deprecate the current map again, if value does not fit.
if (MigrateDeprecated(object)) {
Handle<Object> result;
ASSIGN_RETURN_ON_EXCEPTION(
isolate(), result, Runtime::SetObjectProperty(isolate(), object, key,
value, language_mode()),
Object);
return result;
}
// Check for non-string values that can be converted into an
// internalized string directly or is representable as a smi.
key = TryConvertKey(key, isolate());
Handle<Object> store_handle;
uint32_t index;
if ((key->IsInternalizedString() &&
!String::cast(*key)->AsArrayIndex(&index)) ||
key->IsSymbol()) {
ASSIGN_RETURN_ON_EXCEPTION(
isolate(), store_handle,
StoreIC::Store(object, Handle<Name>::cast(key), value,
JSReceiver::MAY_BE_STORE_FROM_KEYED),
Object);
if (vector_needs_update()) {
if (ConfigureVectorState(MEGAMORPHIC, key)) {
TRACE_GENERIC_IC("unhandled internalized string key");
TRACE_IC("StoreIC", key);
}
}
return store_handle;
}
JSObject::MakePrototypesFast(object, kStartAtPrototype, isolate());
bool use_ic = FLAG_use_ic && !object->IsStringWrapper() &&
!object->IsAccessCheckNeeded() && !object->IsJSGlobalProxy();
if (use_ic && !object->IsSmi()) {
// Don't use ICs for maps of the objects in Array's prototype chain. We
// expect to be able to trap element sets to objects with those maps in
// the runtime to enable optimization of element hole access.
Handle<HeapObject> heap_object = Handle<HeapObject>::cast(object);
if (heap_object->map()->IsMapInArrayPrototypeChain()) {
TRACE_GENERIC_IC("map in array prototype");
use_ic = false;
}
}
Handle<Map> old_receiver_map;
bool is_arguments = false;
bool key_is_valid_index = false;
KeyedAccessStoreMode store_mode = STANDARD_STORE;
if (use_ic && object->IsJSReceiver()) {
Handle<JSReceiver> receiver = Handle<JSReceiver>::cast(object);
old_receiver_map = handle(receiver->map(), isolate());
is_arguments = receiver->IsJSArgumentsObject();
bool is_proxy = receiver->IsJSProxy();
key_is_valid_index = key->IsSmi() && Smi::ToInt(*key) >= 0;
if (!is_arguments && !is_proxy) {
if (key_is_valid_index) {
uint32_t index = static_cast<uint32_t>(Smi::ToInt(*key));
Handle<JSObject> receiver_object = Handle<JSObject>::cast(object);
store_mode = GetStoreMode(receiver_object, index, value);
}
}
}
DCHECK(store_handle.is_null());
ASSIGN_RETURN_ON_EXCEPTION(isolate(), store_handle,
Runtime::SetObjectProperty(isolate(), object, key,
value, language_mode()),
Object);
if (use_ic) {
if (!old_receiver_map.is_null()) {
if (is_arguments) {
TRACE_GENERIC_IC("arguments receiver");
} else if (key_is_valid_index) {
if (old_receiver_map->is_abandoned_prototype_map()) {
TRACE_GENERIC_IC("receiver with prototype map");
} else if (!old_receiver_map
->DictionaryElementsInPrototypeChainOnly()) {
// We should go generic if receiver isn't a dictionary, but our
// prototype chain does have dictionary elements. This ensures that
// other non-dictionary receivers in the polymorphic case benefit
// from fast path keyed stores.
UpdateStoreElement(old_receiver_map, store_mode);
} else {
TRACE_GENERIC_IC("dictionary or proxy prototype");
}
} else {
TRACE_GENERIC_IC("non-smi-like key");
}
} else {
TRACE_GENERIC_IC("non-JSObject receiver");
}
}
if (vector_needs_update()) {
ConfigureVectorState(MEGAMORPHIC, key);
}
TRACE_IC("StoreIC", key);
return store_handle;
}
#undef TRACE_IC
// ----------------------------------------------------------------------------
// Static IC stub generators.
//
// Used from ic-<arch>.cc.
RUNTIME_FUNCTION(Runtime_LoadIC_Miss) {
HandleScope scope(isolate);
DCHECK_EQ(4, args.length());
// Runtime functions don't follow the IC's calling convention.
Handle<Object> receiver = args.at(0);
Handle<Name> key = args.at<Name>(1);
Handle<Smi> slot = args.at<Smi>(2);
Handle<FeedbackVector> vector = args.at<FeedbackVector>(3);
FeedbackSlot vector_slot = vector->ToSlot(slot->value());
// A monomorphic or polymorphic KeyedLoadIC with a string key can call the
// LoadIC miss handler if the handler misses. Since the vector Nexus is
// set up outside the IC, handle that here.
FeedbackSlotKind kind = vector->GetKind(vector_slot);
if (IsLoadICKind(kind)) {
LoadICNexus nexus(vector, vector_slot);
LoadIC ic(isolate, &nexus);
ic.UpdateState(receiver, key);
RETURN_RESULT_OR_FAILURE(isolate, ic.Load(receiver, key));
} else if (IsLoadGlobalICKind(kind)) {
DCHECK_EQ(isolate->native_context()->global_proxy(), *receiver);
receiver = isolate->global_object();
LoadGlobalICNexus nexus(vector, vector_slot);
LoadGlobalIC ic(isolate, &nexus);
ic.UpdateState(receiver, key);
RETURN_RESULT_OR_FAILURE(isolate, ic.Load(key));
} else {
DCHECK(IsKeyedLoadICKind(kind));
KeyedLoadICNexus nexus(vector, vector_slot);
KeyedLoadIC ic(isolate, &nexus);
ic.UpdateState(receiver, key);
RETURN_RESULT_OR_FAILURE(isolate, ic.Load(receiver, key));
}
}
// Used from ic-<arch>.cc.
RUNTIME_FUNCTION(Runtime_LoadGlobalIC_Miss) {
HandleScope scope(isolate);
DCHECK_EQ(3, args.length());
// Runtime functions don't follow the IC's calling convention.
Handle<JSGlobalObject> global = isolate->global_object();
Handle<String> name = args.at<String>(0);
Handle<Smi> slot = args.at<Smi>(1);
Handle<FeedbackVector> vector = args.at<FeedbackVector>(2);
FeedbackSlot vector_slot = vector->ToSlot(slot->value());
LoadGlobalICNexus nexus(vector, vector_slot);
LoadGlobalIC ic(isolate, &nexus);
ic.UpdateState(global, name);
Handle<Object> result;
ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, result, ic.Load(name));
return *result;
}
RUNTIME_FUNCTION(Runtime_LoadGlobalIC_Slow) {
HandleScope scope(isolate);
DCHECK_EQ(3, args.length());
CONVERT_ARG_HANDLE_CHECKED(String, name, 0);
Handle<Context> native_context = isolate->native_context();
Handle<ScriptContextTable> script_contexts(
native_context->script_context_table());
ScriptContextTable::LookupResult lookup_result;
if (ScriptContextTable::Lookup(script_contexts, name, &lookup_result)) {
Handle<Context> script_context = ScriptContextTable::GetContext(
script_contexts, lookup_result.context_index);
Handle<Object> result =
FixedArray::get(*script_context, lookup_result.slot_index, isolate);
if (*result == isolate->heap()->the_hole_value()) {
THROW_NEW_ERROR_RETURN_FAILURE(
isolate, NewReferenceError(MessageTemplate::kNotDefined, name));
}
return *result;
}
Handle<JSGlobalObject> global(native_context->global_object(), isolate);
Handle<Object> result;
bool is_found = false;
ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
isolate, result,
Runtime::GetObjectProperty(isolate, global, name, &is_found));
if (!is_found) {
Handle<Smi> slot = args.at<Smi>(1);
Handle<FeedbackVector> vector = args.at<FeedbackVector>(2);
FeedbackSlot vector_slot = vector->ToSlot(slot->value());
FeedbackSlotKind kind = vector->GetKind(vector_slot);
// It is actually a LoadGlobalICs here but the predicate handles this case
// properly.
if (LoadIC::ShouldThrowReferenceError(kind)) {
THROW_NEW_ERROR_RETURN_FAILURE(
isolate, NewReferenceError(MessageTemplate::kNotDefined, name));
}
}
return *result;
}
// Used from ic-<arch>.cc
RUNTIME_FUNCTION(Runtime_KeyedLoadIC_Miss) {
HandleScope scope(isolate);
DCHECK_EQ(4, args.length());
// Runtime functions don't follow the IC's calling convention.
Handle<Object> receiver = args.at(0);
Handle<Object> key = args.at(1);
Handle<Smi> slot = args.at<Smi>(2);
Handle<FeedbackVector> vector = args.at<FeedbackVector>(3);
FeedbackSlot vector_slot = vector->ToSlot(slot->value());
KeyedLoadICNexus nexus(vector, vector_slot);
KeyedLoadIC ic(isolate, &nexus);
ic.UpdateState(receiver, key);
RETURN_RESULT_OR_FAILURE(isolate, ic.Load(receiver, key));
}
// Used from ic-<arch>.cc.
RUNTIME_FUNCTION(Runtime_StoreIC_Miss) {
HandleScope scope(isolate);
DCHECK_EQ(5, args.length());
// Runtime functions don't follow the IC's calling convention.
Handle<Object> value = args.at(0);
Handle<Smi> slot = args.at<Smi>(1);
Handle<FeedbackVector> vector = args.at<FeedbackVector>(2);
Handle<Object> receiver = args.at(3);
Handle<Name> key = args.at<Name>(4);
FeedbackSlot vector_slot = vector->ToSlot(slot->value());
FeedbackSlotKind kind = vector->GetKind(vector_slot);
if (IsStoreICKind(kind) || IsStoreOwnICKind(kind)) {
StoreICNexus nexus(vector, vector_slot);
StoreIC ic(isolate, &nexus);
ic.UpdateState(receiver, key);
RETURN_RESULT_OR_FAILURE(isolate, ic.Store(receiver, key, value));
} else if (IsStoreGlobalICKind(kind)) {
DCHECK_EQ(isolate->native_context()->global_proxy(), *receiver);
receiver = isolate->global_object();
StoreGlobalICNexus nexus(vector, vector_slot);
StoreGlobalIC ic(isolate, &nexus);
ic.UpdateState(receiver, key);
RETURN_RESULT_OR_FAILURE(isolate, ic.Store(key, value));
} else {
DCHECK(IsKeyedStoreICKind(kind));
KeyedStoreICNexus nexus(vector, vector_slot);
KeyedStoreIC ic(isolate, &nexus);
ic.UpdateState(receiver, key);
RETURN_RESULT_OR_FAILURE(isolate, ic.Store(receiver, key, value));
}
}
RUNTIME_FUNCTION(Runtime_StoreGlobalIC_Miss) {
HandleScope scope(isolate);
DCHECK_EQ(4, args.length());
// Runtime functions don't follow the IC's calling convention.
Handle<Object> value = args.at(0);
Handle<Smi> slot = args.at<Smi>(1);
Handle<FeedbackVector> vector = args.at<FeedbackVector>(2);
Handle<Name> key = args.at<Name>(3);
FeedbackSlot vector_slot = vector->ToSlot(slot->value());
StoreGlobalICNexus nexus(vector, vector_slot);
StoreGlobalIC ic(isolate, &nexus);
Handle<JSGlobalObject> global = isolate->global_object();
ic.UpdateState(global, key);
RETURN_RESULT_OR_FAILURE(isolate, ic.Store(key, value));
}
RUNTIME_FUNCTION(Runtime_StoreGlobalIC_Slow) {
HandleScope scope(isolate);
DCHECK_EQ(5, args.length());
// Runtime functions don't follow the IC's calling convention.
Handle<Object> value = args.at(0);
Handle<Smi> slot = args.at<Smi>(1);
Handle<FeedbackVector> vector = args.at<FeedbackVector>(2);
CONVERT_ARG_HANDLE_CHECKED(String, name, 4);
#ifdef DEBUG
{
FeedbackSlot vector_slot = vector->ToSlot(slot->value());
FeedbackSlotKind slot_kind = vector->GetKind(vector_slot);
DCHECK(IsStoreGlobalICKind(slot_kind));
Handle<Object> receiver = args.at(3);
DCHECK(receiver->IsJSGlobalProxy());
}
#endif
Handle<JSGlobalObject> global = isolate->global_object();
Handle<Context> native_context = isolate->native_context();
Handle<ScriptContextTable> script_contexts(
native_context->script_context_table());
ScriptContextTable::LookupResult lookup_result;
if (ScriptContextTable::Lookup(script_contexts, name, &lookup_result)) {
Handle<Context> script_context = ScriptContextTable::GetContext(
script_contexts, lookup_result.context_index);
if (lookup_result.mode == CONST) {
THROW_NEW_ERROR_RETURN_FAILURE(
isolate, NewTypeError(MessageTemplate::kConstAssign, global, name));
}
Handle<Object> previous_value =
FixedArray::get(*script_context, lookup_result.slot_index, isolate);
if (previous_value->IsTheHole(isolate)) {
THROW_NEW_ERROR_RETURN_FAILURE(
isolate, NewReferenceError(MessageTemplate::kNotDefined, name));
}
script_context->set(lookup_result.slot_index, *value);
return *value;
}
FeedbackSlot vector_slot = vector->ToSlot(slot->value());
LanguageMode language_mode = vector->GetLanguageMode(vector_slot);
RETURN_RESULT_OR_FAILURE(
isolate,
Runtime::SetObjectProperty(isolate, global, name, value, language_mode));
}
// Used from ic-<arch>.cc.
RUNTIME_FUNCTION(Runtime_KeyedStoreIC_Miss) {
HandleScope scope(isolate);
DCHECK_EQ(5, args.length());
// Runtime functions don't follow the IC's calling convention.
Handle<Object> value = args.at(0);
Handle<Smi> slot = args.at<Smi>(1);
Handle<FeedbackVector> vector = args.at<FeedbackVector>(2);
Handle<Object> receiver = args.at(3);
Handle<Object> key = args.at(4);
FeedbackSlot vector_slot = vector->ToSlot(slot->value());
KeyedStoreICNexus nexus(vector, vector_slot);
KeyedStoreIC ic(isolate, &nexus);
ic.UpdateState(receiver, key);
RETURN_RESULT_OR_FAILURE(isolate, ic.Store(receiver, key, value));
}
RUNTIME_FUNCTION(Runtime_KeyedStoreIC_Slow) {
HandleScope scope(isolate);
DCHECK_EQ(5, args.length());
// Runtime functions don't follow the IC's calling convention.
Handle<Object> value = args.at(0);
Handle<Smi> slot = args.at<Smi>(1);
Handle<FeedbackVector> vector = args.at<FeedbackVector>(2);
Handle<Object> object = args.at(3);
Handle<Object> key = args.at(4);
FeedbackSlot vector_slot = vector->ToSlot(slot->value());
LanguageMode language_mode = vector->GetLanguageMode(vector_slot);
RETURN_RESULT_OR_FAILURE(
isolate,
Runtime::SetObjectProperty(isolate, object, key, value, language_mode));
}
RUNTIME_FUNCTION(Runtime_ElementsTransitionAndStoreIC_Miss) {
HandleScope scope(isolate);
DCHECK_EQ(6, args.length());
// Runtime functions don't follow the IC's calling convention.
Handle<Object> object = args.at(0);
Handle<Object> key = args.at(1);
Handle<Object> value = args.at(2);
Handle<Map> map = args.at<Map>(3);
Handle<Smi> slot = args.at<Smi>(4);
Handle<FeedbackVector> vector = args.at<FeedbackVector>(5);
FeedbackSlot vector_slot = vector->ToSlot(slot->value());
LanguageMode language_mode = vector->GetLanguageMode(vector_slot);
if (object->IsJSObject()) {
JSObject::TransitionElementsKind(Handle<JSObject>::cast(object),
map->elements_kind());
}
RETURN_RESULT_OR_FAILURE(
isolate,
Runtime::SetObjectProperty(isolate, object, key, value, language_mode));
}
RUNTIME_FUNCTION(Runtime_Unreachable) {
UNREACHABLE();
}
RUNTIME_FUNCTION(Runtime_StoreCallbackProperty) {
Handle<JSObject> receiver = args.at<JSObject>(0);
Handle<JSObject> holder = args.at<JSObject>(1);
Handle<HeapObject> callback_or_cell = args.at<HeapObject>(2);
Handle<Name> name = args.at<Name>(3);
Handle<Object> value = args.at(4);
CONVERT_LANGUAGE_MODE_ARG_CHECKED(language_mode, 5);
HandleScope scope(isolate);
if (V8_UNLIKELY(FLAG_runtime_stats)) {
RETURN_RESULT_OR_FAILURE(
isolate, Runtime::SetObjectProperty(isolate, receiver, name, value,
language_mode));
}
Handle<AccessorInfo> info(
callback_or_cell->IsWeakCell()
? AccessorInfo::cast(WeakCell::cast(*callback_or_cell)->value())
: AccessorInfo::cast(*callback_or_cell));
DCHECK(info->IsCompatibleReceiver(*receiver));
ShouldThrow should_throw =
is_sloppy(language_mode) ? kDontThrow : kThrowOnError;
PropertyCallbackArguments arguments(isolate, info->data(), *receiver, *holder,
should_throw);
arguments.CallAccessorSetter(info, name, value);
RETURN_FAILURE_IF_SCHEDULED_EXCEPTION(isolate);
return *value;
}
/**
* Loads a property with an interceptor performing post interceptor
* lookup if interceptor failed.
*/
RUNTIME_FUNCTION(Runtime_LoadPropertyWithInterceptor) {
HandleScope scope(isolate);
DCHECK_EQ(5, args.length());
Handle<Name> name = args.at<Name>(0);
Handle<Object> receiver = args.at(1);
Handle<JSObject> holder = args.at<JSObject>(2);
if (!receiver->IsJSReceiver()) {
ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
isolate, receiver, Object::ConvertReceiver(isolate, receiver));
}
Handle<InterceptorInfo> interceptor(holder->GetNamedInterceptor(), isolate);
PropertyCallbackArguments arguments(isolate, interceptor->data(), *receiver,
*holder, kDontThrow);
Handle<Object> result = arguments.CallNamedGetter(interceptor, name);
RETURN_FAILURE_IF_SCHEDULED_EXCEPTION(isolate);
if (!result.is_null()) return *result;
LookupIterator it(receiver, name, holder);
// Skip any lookup work until we hit the (possibly non-masking) interceptor.
while (it.state() != LookupIterator::INTERCEPTOR ||
!it.GetHolder<JSObject>().is_identical_to(holder)) {
DCHECK(it.state() != LookupIterator::ACCESS_CHECK || it.HasAccess());
it.Next();
}
// Skip past the interceptor.
it.Next();
ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, result, Object::GetProperty(&it));
if (it.IsFound()) return *result;
Handle<Smi> slot = args.at<Smi>(3);
Handle<FeedbackVector> vector = args.at<FeedbackVector>(4);
FeedbackSlot vector_slot = vector->ToSlot(slot->value());
FeedbackSlotKind slot_kind = vector->GetKind(vector_slot);
// It could actually be any kind of load IC slot here but the predicate
// handles all the cases properly.
if (!LoadIC::ShouldThrowReferenceError(slot_kind)) {
return isolate->heap()->undefined_value();
}
// Throw a reference error.
THROW_NEW_ERROR_RETURN_FAILURE(
isolate, NewReferenceError(MessageTemplate::kNotDefined, it.name()));
}
RUNTIME_FUNCTION(Runtime_StorePropertyWithInterceptor) {
HandleScope scope(isolate);
DCHECK_EQ(5, args.length());
// Runtime functions don't follow the IC's calling convention.
Handle<Object> value = args.at(0);
Handle<Smi> slot = args.at<Smi>(1);
Handle<FeedbackVector> vector = args.at<FeedbackVector>(2);
Handle<JSObject> receiver = args.at<JSObject>(3);
Handle<Name> name = args.at<Name>(4);
FeedbackSlot vector_slot = vector->ToSlot(slot->value());
LanguageMode language_mode = vector->GetLanguageMode(vector_slot);
// TODO(ishell): Cache interceptor_holder in the store handler like we do
// for LoadHandler::kInterceptor case.
Handle<JSObject> interceptor_holder = receiver;
if (receiver->IsJSGlobalProxy()) {
FeedbackSlotKind kind = vector->GetKind(vector_slot);
if (IsStoreGlobalICKind(kind)) {