blob: 62669ca60bbd1f2bfcaf31541388dd946b70fa92 [file] [log] [blame]
// Copyright 2012 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "src/ic/ic.h"
#include "src/accessors.h"
#include "src/api.h"
#include "src/arguments.h"
#include "src/base/bits.h"
#include "src/codegen.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-compiler.h"
#include "src/ic/ic-inl.h"
#include "src/ic/ic-compiler.h"
#include "src/ic/stub-cache.h"
#include "src/isolate-inl.h"
#include "src/macro-assembler.h"
#include "src/prototype.h"
#include "src/runtime/runtime.h"
#include "src/runtime/runtime-utils.h"
#include "src/tracing/trace-event.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 PROTOTYPE_FAILURE:
return '^';
case POLYMORPHIC:
return 'P';
case MEGAMORPHIC:
return 'N';
case GENERIC:
return 'G';
// 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_STUB:
break;
}
UNREACHABLE();
return 0;
}
const char* GetTransitionMarkModifier(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 "";
}
#ifdef DEBUG
#define TRACE_GENERIC_IC(isolate, type, reason) \
do { \
if (FLAG_trace_ic) { \
PrintF("[%s patching generic stub in ", type); \
JavaScriptFrame::PrintTop(isolate, stdout, false, true); \
PrintF(" (%s)]\n", reason); \
} \
} while (false)
#else
#define TRACE_GENERIC_IC(isolate, type, reason) \
do { \
if (FLAG_trace_ic) { \
PrintF("[%s patching generic stub in ", type); \
PrintF("(see below) (%s)]\n", reason); \
} \
} while (false)
#endif // DEBUG
void IC::TraceIC(const char* type, Handle<Object> name) {
if (FLAG_trace_ic) {
if (AddressIsDeoptimizedCode()) return;
State new_state =
UseVector() ? nexus()->StateFromFeedback() : raw_target()->ic_state();
TraceIC(type, name, state(), new_state);
}
}
void IC::TraceIC(const char* type, Handle<Object> name, State old_state,
State new_state) {
if (FLAG_trace_ic) {
Code* new_target = raw_target();
PrintF("[%s%s in ", new_target->is_keyed_stub() ? "Keyed" : "", type);
// TODO(jkummerow): Add support for "apply". The logic is roughly:
// marker = [fp_ + kMarkerOffset];
// if marker is smi and marker.value == INTERNAL and
// the frame's code == builtin(Builtins::kFunctionApply):
// then print "apply from" and advance one frame
Object* maybe_function =
Memory::Object_at(fp_ + JavaScriptFrameConstants::kFunctionOffset);
if (maybe_function->IsJSFunction()) {
JSFunction* function = JSFunction::cast(maybe_function);
JavaScriptFrame::PrintFunctionAndOffset(function, function->code(), pc(),
stdout, true);
}
const char* modifier = "";
if (new_target->kind() == Code::KEYED_STORE_IC) {
KeyedAccessStoreMode mode =
casted_nexus<KeyedStoreICNexus>()->GetKeyedAccessStoreMode();
modifier = GetTransitionMarkModifier(mode);
}
PrintF(" (%c->%c%s) ", TransitionMarkFromState(old_state),
TransitionMarkFromState(new_state), modifier);
#ifdef OBJECT_PRINT
OFStream os(stdout);
name->Print(os);
#else
name->ShortPrint(stdout);
#endif
PrintF("]\n");
}
}
#define TRACE_IC(type, name) TraceIC(type, name)
IC::IC(FrameDepth depth, Isolate* isolate, FeedbackNexus* nexus)
: isolate_(isolate),
target_set_(false),
vector_set_(false),
target_maps_set_(false),
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 = NULL;
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 or a
// StubFailureTrampoline, 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
fp_ = fp;
if (FLAG_enable_embedded_constant_pool) {
constant_pool_address_ = constant_pool;
}
pc_address_ = StackFrame::ResolveReturnAddressLocation(pc_address);
target_ = handle(raw_target(), isolate);
kind_ = target_->kind();
state_ = UseVector() ? nexus->StateFromFeedback() : target_->ic_state();
old_state_ = state_;
extra_ic_state_ = target_->extra_ic_state();
}
SharedFunctionInfo* IC::GetSharedFunctionInfo() 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();
if (FLAG_ignition && it.frame()->type() == StackFrame::STUB) {
// Advance over bytecode handler frame.
// TODO(rmcilroy): Remove this once bytecode handlers don't need a frame.
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 = frame->function();
return function->shared();
}
Code* IC::GetCode() const {
HandleScope scope(isolate());
Handle<SharedFunctionInfo> shared(GetSharedFunctionInfo(), isolate());
Code* code = shared->code();
return code;
}
bool IC::AddressIsOptimizedCode() const {
Code* host =
isolate()->inner_pointer_to_code_cache()->GetCacheEntry(address())->code;
return host->kind() == Code::OPTIMIZED_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()) {
return;
}
break;
}
case LookupIterator::ACCESS_CHECK:
// PropertyHandlerCompiler::CheckPrototypes() knows how to emit
// access checks for 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::TryRemoveInvalidPrototypeDependentStub(Handle<Object> receiver,
Handle<String> name) {
if (!IsNameCompatibleWithPrototypeFailure(name)) return false;
if (UseVector()) {
maybe_handler_ = nexus()->FindHandlerForMap(receiver_map());
} else {
maybe_handler_ = target()->FindHandlerForMap(*receiver_map());
}
// 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 == NULL) 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());
}
CacheHolderFlag flag;
Handle<Map> ic_holder_map(GetICCacheHolder(receiver_map(), isolate(), &flag));
DCHECK(flag != kCacheOnReceiver || receiver->IsJSObject());
DCHECK(flag != kCacheOnPrototype || !receiver->IsJSReceiver());
DCHECK(flag != kCacheOnPrototypeReceiverIsDictionary);
if (state() == MONOMORPHIC) {
int index = ic_holder_map->IndexInCodeCache(*name, *target());
if (index >= 0) {
ic_holder_map->RemoveFromCodeCache(*name, *target(), index);
}
}
if (receiver->IsJSGlobalObject()) {
Handle<JSGlobalObject> global = Handle<JSGlobalObject>::cast(receiver);
LookupIterator it(global, name, LookupIterator::OWN_SKIP_INTERCEPTOR);
if (it.state() == LookupIterator::ACCESS_CHECK) return false;
if (!it.IsFound()) return false;
return it.property_details().cell_type() == PropertyCellType::kConstant;
}
return true;
}
bool IC::IsNameCompatibleWithPrototypeFailure(Handle<Object> name) {
if (target()->is_keyed_stub()) {
// Determine whether the failure is due to a name failure.
if (!name->IsName()) return false;
Name* stub_name =
UseVector() ? nexus()->FindFirstName() : target()->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->IsUndefined() || receiver->IsNull()) 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 (TryRemoveInvalidPrototypeDependentStub(receiver,
Handle<String>::cast(name))) {
MarkPrototypeFailure(name);
return;
}
}
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 ComputeTypeInfoCountDelta(IC::State old_state, IC::State new_state,
int* polymorphic_delta,
int* generic_delta) {
switch (old_state) {
case UNINITIALIZED:
case PREMONOMORPHIC:
if (new_state == UNINITIALIZED || new_state == PREMONOMORPHIC) break;
if (new_state == MONOMORPHIC || new_state == POLYMORPHIC) {
*polymorphic_delta = 1;
} else if (new_state == MEGAMORPHIC || new_state == GENERIC) {
*generic_delta = 1;
}
break;
case MONOMORPHIC:
case POLYMORPHIC:
if (new_state == MONOMORPHIC || new_state == POLYMORPHIC) break;
*polymorphic_delta = -1;
if (new_state == MEGAMORPHIC || new_state == GENERIC) {
*generic_delta = 1;
}
break;
case MEGAMORPHIC:
case GENERIC:
if (new_state == MEGAMORPHIC || new_state == GENERIC) break;
*generic_delta = -1;
if (new_state == MONOMORPHIC || new_state == POLYMORPHIC) {
*polymorphic_delta = 1;
}
break;
case PROTOTYPE_FAILURE:
case DEBUG_STUB:
UNREACHABLE();
}
}
void IC::OnTypeFeedbackChanged(Isolate* isolate, Address address,
State old_state, State new_state,
bool target_remains_ic_stub) {
Code* host =
isolate->inner_pointer_to_code_cache()->GetCacheEntry(address)->code;
if (host->kind() != Code::FUNCTION) return;
if (FLAG_type_info_threshold > 0 && target_remains_ic_stub &&
// Not all Code objects have TypeFeedbackInfo.
host->type_feedback_info()->IsTypeFeedbackInfo()) {
int polymorphic_delta = 0; // "Polymorphic" here includes monomorphic.
int generic_delta = 0; // "Generic" here includes megamorphic.
ComputeTypeInfoCountDelta(old_state, new_state, &polymorphic_delta,
&generic_delta);
TypeFeedbackInfo* info = TypeFeedbackInfo::cast(host->type_feedback_info());
info->change_ic_with_type_info_count(polymorphic_delta);
info->change_ic_generic_count(generic_delta);
}
if (host->type_feedback_info()->IsTypeFeedbackInfo()) {
TypeFeedbackInfo* info = TypeFeedbackInfo::cast(host->type_feedback_info());
info->change_own_type_change_checksum();
}
host->set_profiler_ticks(0);
isolate->runtime_profiler()->NotifyICChanged();
// TODO(2029): When an optimized function is patched, it would
// be nice to propagate the corresponding type information to its
// unoptimized version for the benefit of later inlining.
}
// static
void IC::OnTypeFeedbackChanged(Isolate* isolate, Code* host) {
if (host->kind() != Code::FUNCTION) return;
TypeFeedbackInfo* info = TypeFeedbackInfo::cast(host->type_feedback_info());
info->change_own_type_change_checksum();
host->set_profiler_ticks(0);
isolate->runtime_profiler()->NotifyICChanged();
// TODO(2029): When an optimized function is patched, it would
// be nice to propagate the corresponding type information to its
// unoptimized version for the benefit of later inlining.
}
void IC::PostPatching(Address address, Code* target, Code* old_target) {
// Type vector based ICs update these statistics at a different time because
// they don't always patch on state change.
if (ICUseVector(target->kind())) return;
Isolate* isolate = target->GetHeap()->isolate();
State old_state = UNINITIALIZED;
State new_state = UNINITIALIZED;
bool target_remains_ic_stub = false;
if (old_target->is_inline_cache_stub() && target->is_inline_cache_stub()) {
old_state = old_target->ic_state();
new_state = target->ic_state();
target_remains_ic_stub = true;
}
OnTypeFeedbackChanged(isolate, address, old_state, new_state,
target_remains_ic_stub);
}
void IC::Clear(Isolate* isolate, Address address, Address constant_pool) {
Code* target = GetTargetAtAddress(address, constant_pool);
// Don't clear debug break inline cache as it will remove the break point.
if (target->is_debug_stub()) return;
switch (target->kind()) {
case Code::LOAD_IC:
case Code::KEYED_LOAD_IC:
case Code::STORE_IC:
case Code::KEYED_STORE_IC:
return;
case Code::COMPARE_IC:
return CompareIC::Clear(isolate, address, target, constant_pool);
case Code::COMPARE_NIL_IC:
return CompareNilIC::Clear(address, target, constant_pool);
case Code::CALL_IC: // CallICs are vector-based and cleared differently.
case Code::BINARY_OP_IC:
case Code::TO_BOOLEAN_IC:
// Clearing these is tricky and does not
// make any performance difference.
return;
default:
UNREACHABLE();
}
}
void KeyedLoadIC::Clear(Isolate* isolate, Code* host, KeyedLoadICNexus* nexus) {
if (IsCleared(nexus)) 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.
nexus->ConfigurePremonomorphic();
OnTypeFeedbackChanged(isolate, host);
}
void CallIC::Clear(Isolate* isolate, Code* host, CallICNexus* nexus) {
// Determine our state.
Object* feedback = nexus->vector()->Get(nexus->slot());
State state = nexus->StateFromFeedback();
if (state != UNINITIALIZED && !feedback->IsAllocationSite()) {
nexus->ConfigureUninitialized();
// The change in state must be processed.
OnTypeFeedbackChanged(isolate, host);
}
}
void LoadIC::Clear(Isolate* isolate, Code* host, LoadICNexus* nexus) {
if (IsCleared(nexus)) return;
nexus->ConfigurePremonomorphic();
OnTypeFeedbackChanged(isolate, host);
}
void StoreIC::Clear(Isolate* isolate, Address address, Code* target,
Address constant_pool) {
if (IsCleared(target)) return;
Code* code = PropertyICCompiler::FindPreMonomorphic(isolate, Code::STORE_IC,
target->extra_ic_state());
SetTargetAtAddress(address, code, constant_pool);
}
void StoreIC::Clear(Isolate* isolate, Code* host, StoreICNexus* nexus) {
if (IsCleared(nexus)) return;
nexus->ConfigurePremonomorphic();
OnTypeFeedbackChanged(isolate, host);
}
void KeyedStoreIC::Clear(Isolate* isolate, Address address, Code* target,
Address constant_pool) {
if (IsCleared(target)) return;
Handle<Code> code = pre_monomorphic_stub(
isolate, StoreICState::GetLanguageMode(target->extra_ic_state()));
SetTargetAtAddress(address, *code, constant_pool);
}
void KeyedStoreIC::Clear(Isolate* isolate, Code* host,
KeyedStoreICNexus* nexus) {
if (IsCleared(nexus)) return;
nexus->ConfigurePremonomorphic();
OnTypeFeedbackChanged(isolate, host);
}
void CompareIC::Clear(Isolate* isolate, Address address, Code* target,
Address constant_pool) {
DCHECK(CodeStub::GetMajorKey(target) == CodeStub::CompareIC);
CompareICStub stub(target->stub_key(), isolate);
// Only clear CompareICs that can retain objects.
if (stub.state() != CompareICState::KNOWN_RECEIVER) return;
SetTargetAtAddress(address, GetRawUninitialized(isolate, stub.op()),
constant_pool);
PatchInlinedSmiCode(isolate, address, DISABLE_INLINED_SMI_CHECK);
}
// static
Handle<Code> KeyedLoadIC::ChooseMegamorphicStub(Isolate* isolate,
ExtraICState extra_state) {
if (FLAG_compiled_keyed_generic_loads) {
return KeyedLoadGenericStub(isolate, LoadICState(extra_state)).GetCode();
} else {
return isolate->builtins()->KeyedLoadIC_Megamorphic();
}
}
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;
}
void IC::ConfigureVectorState(IC::State new_state, Handle<Object> key) {
DCHECK(UseVector());
if (new_state == PREMONOMORPHIC) {
nexus()->ConfigurePremonomorphic();
} else if (new_state == MEGAMORPHIC) {
if (kind() == Code::LOAD_IC || kind() == Code::STORE_IC) {
nexus()->ConfigureMegamorphic();
} else if (kind() == Code::KEYED_LOAD_IC) {
KeyedLoadICNexus* nexus = casted_nexus<KeyedLoadICNexus>();
nexus->ConfigureMegamorphicKeyed(key->IsName() ? PROPERTY : ELEMENT);
} else {
DCHECK(kind() == Code::KEYED_STORE_IC);
KeyedStoreICNexus* nexus = casted_nexus<KeyedStoreICNexus>();
nexus->ConfigureMegamorphicKeyed(key->IsName() ? PROPERTY : ELEMENT);
}
} else {
UNREACHABLE();
}
vector_set_ = true;
OnTypeFeedbackChanged(isolate(), get_host());
}
void IC::ConfigureVectorState(Handle<Name> name, Handle<Map> map,
Handle<Code> handler) {
DCHECK(UseVector());
if (kind() == Code::LOAD_IC) {
LoadICNexus* nexus = casted_nexus<LoadICNexus>();
nexus->ConfigureMonomorphic(map, handler);
} else if (kind() == Code::KEYED_LOAD_IC) {
KeyedLoadICNexus* nexus = casted_nexus<KeyedLoadICNexus>();
nexus->ConfigureMonomorphic(name, map, handler);
} else if (kind() == Code::STORE_IC) {
StoreICNexus* nexus = casted_nexus<StoreICNexus>();
nexus->ConfigureMonomorphic(map, handler);
} else {
DCHECK(kind() == Code::KEYED_STORE_IC);
KeyedStoreICNexus* nexus = casted_nexus<KeyedStoreICNexus>();
nexus->ConfigureMonomorphic(name, map, handler);
}
vector_set_ = true;
OnTypeFeedbackChanged(isolate(), get_host());
}
void IC::ConfigureVectorState(Handle<Name> name, MapHandleList* maps,
CodeHandleList* handlers) {
DCHECK(UseVector());
if (kind() == Code::LOAD_IC) {
LoadICNexus* nexus = casted_nexus<LoadICNexus>();
nexus->ConfigurePolymorphic(maps, handlers);
} else if (kind() == Code::KEYED_LOAD_IC) {
KeyedLoadICNexus* nexus = casted_nexus<KeyedLoadICNexus>();
nexus->ConfigurePolymorphic(name, maps, handlers);
} else if (kind() == Code::STORE_IC) {
StoreICNexus* nexus = casted_nexus<StoreICNexus>();
nexus->ConfigurePolymorphic(maps, handlers);
} else {
DCHECK(kind() == Code::KEYED_STORE_IC);
KeyedStoreICNexus* nexus = casted_nexus<KeyedStoreICNexus>();
nexus->ConfigurePolymorphic(name, maps, handlers);
}
vector_set_ = true;
OnTypeFeedbackChanged(isolate(), get_host());
}
void IC::ConfigureVectorState(MapHandleList* maps,
MapHandleList* transitioned_maps,
CodeHandleList* handlers) {
DCHECK(UseVector());
DCHECK(kind() == Code::KEYED_STORE_IC);
KeyedStoreICNexus* nexus = casted_nexus<KeyedStoreICNexus>();
nexus->ConfigurePolymorphic(maps, transitioned_maps, handlers);
vector_set_ = true;
OnTypeFeedbackChanged(isolate(), get_host());
}
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->IsUndefined() || object->IsNull()) {
return TypeError(MessageTemplate::kNonObjectPropertyLoad, object, name);
}
// Check if the name is trivially convertible to an index and get
// the element or char if so.
uint32_t index;
if (kind() == Code::KEYED_LOAD_IC && name->AsArrayIndex(&index)) {
// Rewrite to the generic keyed load stub.
if (FLAG_use_ic) {
DCHECK(UseVector());
ConfigureVectorState(MEGAMORPHIC, name);
TRACE_IC("LoadIC", name);
TRACE_GENERIC_IC(isolate(), "LoadIC", "name as array index");
}
Handle<Object> result;
ASSIGN_RETURN_ON_EXCEPTION(isolate(), result,
Object::GetElement(isolate(), object, index),
Object);
return result;
}
bool use_ic = MigrateDeprecated(object) ? false : FLAG_use_ic;
if (object->IsJSGlobalObject() && name->IsString()) {
// Look up in script context table.
Handle<String> str_name = Handle<String>::cast(name);
Handle<JSGlobalObject> global = Handle<JSGlobalObject>::cast(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<Object> result =
FixedArray::get(*ScriptContextTable::GetContext(
script_contexts, lookup_result.context_index),
lookup_result.slot_index, isolate());
if (*result == *isolate()->factory()->the_hole_value()) {
// Do not install stubs and stay pre-monomorphic for
// uninitialized accesses.
return ReferenceError(name);
}
if (use_ic && LoadScriptContextFieldStub::Accepted(&lookup_result)) {
LoadScriptContextFieldStub stub(isolate(), &lookup_result);
PatchCache(name, stub.GetCode());
}
return result;
}
}
// Named lookup in the object.
LookupIterator it(object, name);
LookupForRead(&it);
if (it.IsFound() || !ShouldThrowReferenceError(object)) {
// 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(object)) {
LOG(isolate(), SuspectReadEvent(*name, *object));
return result;
}
}
return ReferenceError(name);
}
static bool AddOneReceiverMapIfMissing(MapHandleList* receiver_maps,
Handle<Map> new_receiver_map) {
DCHECK(!new_receiver_map.is_null());
for (int current = 0; current < receiver_maps->length(); ++current) {
if (!receiver_maps->at(current).is_null() &&
receiver_maps->at(current).is_identical_to(new_receiver_map)) {
return false;
}
}
receiver_maps->Add(new_receiver_map);
return true;
}
bool IC::UpdatePolymorphicIC(Handle<Name> name, Handle<Code> code) {
if (!code->is_handler()) return false;
if (target()->is_keyed_stub() && state() != PROTOTYPE_FAILURE) return false;
Handle<Map> map = receiver_map();
MapHandleList maps;
CodeHandleList handlers;
TargetMaps(&maps);
int number_of_maps = maps.length();
int deprecated_maps = 0;
int handler_to_overwrite = -1;
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 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 >= 4) return false;
if (number_of_maps == 0 && state() != MONOMORPHIC && state() != POLYMORPHIC) {
return false;
}
if (UseVector()) {
if (!nexus()->FindHandlers(&handlers, maps.length())) return false;
} else {
if (!target()->FindHandlers(&handlers, maps.length())) return false;
}
number_of_valid_maps++;
if (number_of_valid_maps > 1 && target()->is_keyed_stub()) return false;
Handle<Code> ic;
if (number_of_valid_maps == 1) {
ConfigureVectorState(name, receiver_map(), code);
} else {
if (handler_to_overwrite >= 0) {
handlers.Set(handler_to_overwrite, code);
if (!map.is_identical_to(maps.at(handler_to_overwrite))) {
maps.Set(handler_to_overwrite, map);
}
} else {
maps.Add(map);
handlers.Add(code);
}
ConfigureVectorState(name, &maps, &handlers);
}
if (!UseVector()) set_target(*ic);
return true;
}
void IC::UpdateMonomorphicIC(Handle<Code> handler, Handle<Name> name) {
DCHECK(handler->is_handler());
ConfigureVectorState(name, receiver_map(), handler);
}
void IC::CopyICToMegamorphicCache(Handle<Name> name) {
MapHandleList maps;
CodeHandleList handlers;
TargetMaps(&maps);
if (!target()->FindHandlers(&handlers, maps.length())) return;
for (int i = 0; i < maps.length(); i++) {
UpdateMegamorphicCache(*maps.at(i), *name, *handlers.at(i));
}
}
bool IC::IsTransitionOfMonomorphicTarget(Map* source_map, Map* target_map) {
if (source_map == NULL) return true;
if (target_map == NULL) 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) {
MapHandleList map_list;
map_list.Add(handle(target_map));
transitioned_map = source_map->FindElementsKindTransitionedMap(&map_list);
}
return transitioned_map == target_map;
}
void IC::PatchCache(Handle<Name> name, Handle<Code> code) {
switch (state()) {
case UNINITIALIZED:
case PREMONOMORPHIC:
UpdateMonomorphicIC(code, name);
break;
case PROTOTYPE_FAILURE:
case MONOMORPHIC:
case POLYMORPHIC:
if (!target()->is_keyed_stub() || state() == PROTOTYPE_FAILURE) {
if (UpdatePolymorphicIC(name, code)) break;
// For keyed stubs, we can't know whether old handlers were for the
// same key.
CopyICToMegamorphicCache(name);
}
if (UseVector()) {
ConfigureVectorState(MEGAMORPHIC, name);
} else {
set_target(*megamorphic_stub());
}
// Fall through.
case MEGAMORPHIC:
UpdateMegamorphicCache(*receiver_map(), *name, *code);
// Indicate that we've handled this case.
if (UseVector()) {
vector_set_ = true;
} else {
target_set_ = true;
}
break;
case DEBUG_STUB:
break;
case GENERIC:
UNREACHABLE();
break;
}
}
Handle<Code> LoadIC::initialize_stub(Isolate* isolate,
ExtraICState extra_state) {
return LoadICTrampolineStub(isolate, LoadICState(extra_state)).GetCode();
}
Handle<Code> LoadIC::initialize_stub_in_optimized_code(
Isolate* isolate, ExtraICState extra_state, State initialization_state) {
return LoadICStub(isolate, LoadICState(extra_state)).GetCode();
}
Handle<Code> KeyedLoadIC::initialize_stub(Isolate* isolate,
ExtraICState extra_state) {
return KeyedLoadICTrampolineStub(isolate, LoadICState(extra_state)).GetCode();
}
Handle<Code> KeyedLoadIC::initialize_stub_in_optimized_code(
Isolate* isolate, State initialization_state, ExtraICState extra_state) {
if (initialization_state != MEGAMORPHIC) {
return KeyedLoadICStub(isolate, LoadICState(extra_state)).GetCode();
}
return isolate->builtins()->KeyedLoadIC_Megamorphic();
}
static Handle<Code> KeyedStoreICInitializeStubHelper(
Isolate* isolate, LanguageMode language_mode,
InlineCacheState initialization_state) {
switch (initialization_state) {
case UNINITIALIZED:
return is_strict(language_mode)
? isolate->builtins()->KeyedStoreIC_Initialize_Strict()
: isolate->builtins()->KeyedStoreIC_Initialize();
case PREMONOMORPHIC:
return is_strict(language_mode)
? isolate->builtins()->KeyedStoreIC_PreMonomorphic_Strict()
: isolate->builtins()->KeyedStoreIC_PreMonomorphic();
case MEGAMORPHIC:
return is_strict(language_mode)
? isolate->builtins()->KeyedStoreIC_Megamorphic_Strict()
: isolate->builtins()->KeyedStoreIC_Megamorphic();
default:
UNREACHABLE();
}
return Handle<Code>();
}
Handle<Code> KeyedStoreIC::initialize_stub(Isolate* isolate,
LanguageMode language_mode,
State initialization_state) {
if (initialization_state != MEGAMORPHIC) {
VectorKeyedStoreICTrampolineStub stub(isolate, StoreICState(language_mode));
return stub.GetCode();
}
return KeyedStoreICInitializeStubHelper(isolate, language_mode,
initialization_state);
}
Handle<Code> KeyedStoreIC::initialize_stub_in_optimized_code(
Isolate* isolate, LanguageMode language_mode, State initialization_state) {
if (initialization_state != MEGAMORPHIC) {
VectorKeyedStoreICStub stub(isolate, StoreICState(language_mode));
return stub.GetCode();
}
return KeyedStoreICInitializeStubHelper(isolate, language_mode,
initialization_state);
}
Handle<Code> KeyedStoreIC::ChooseMegamorphicStub(Isolate* isolate,
ExtraICState extra_state) {
LanguageMode mode = StoreICState::GetLanguageMode(extra_state);
return KeyedStoreICInitializeStubHelper(isolate, mode, MEGAMORPHIC);
}
Handle<Code> LoadIC::megamorphic_stub() {
DCHECK_EQ(Code::KEYED_LOAD_IC, kind());
return KeyedLoadIC::ChooseMegamorphicStub(isolate(), extra_ic_state());
}
Handle<Code> LoadIC::SimpleFieldLoad(FieldIndex index) {
LoadFieldStub stub(isolate(), index);
return stub.GetCode();
}
bool IsCompatibleReceiver(LookupIterator* lookup, Handle<Map> receiver_map) {
DCHECK(lookup->state() == LookupIterator::ACCESSOR);
Isolate* isolate = lookup->isolate();
Handle<Object> accessors = lookup->GetAccessors();
if (accessors->IsAccessorInfo()) {
Handle<AccessorInfo> info = Handle<AccessorInfo>::cast(accessors);
if (info->getter() != NULL &&
!AccessorInfo::IsCompatibleReceiverMap(isolate, info, receiver_map)) {
return false;
}
} else if (accessors->IsAccessorPair()) {
Handle<Object> getter(Handle<AccessorPair>::cast(accessors)->getter(),
isolate);
if (!getter->IsJSFunction() && !getter->IsFunctionTemplateInfo())
return false;
Handle<JSObject> holder = lookup->GetHolder<JSObject>();
Handle<Object> receiver = lookup->GetReceiver();
if (holder->HasFastProperties()) {
if (getter->IsJSFunction()) {
Handle<JSFunction> function = Handle<JSFunction>::cast(getter);
if (!receiver->IsJSObject() && !function->shared()->IsBuiltin() &&
is_sloppy(function->shared()->language_mode())) {
// Calling sloppy non-builtins with a value as the receiver
// requires boxing.
return false;
}
}
CallOptimization call_optimization(getter);
if (call_optimization.is_simple_api_call() &&
!call_optimization.IsCompatibleReceiverMap(receiver_map, holder)) {
return false;
}
}
}
return true;
}
void LoadIC::UpdateCaches(LookupIterator* lookup) {
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.
ConfigureVectorState(PREMONOMORPHIC, Handle<Object>());
TRACE_IC("LoadIC", lookup->name());
return;
}
Handle<Code> code;
if (lookup->state() == LookupIterator::JSPROXY ||
lookup->state() == LookupIterator::ACCESS_CHECK) {
code = slow_stub();
} else if (!lookup->IsFound()) {
if (kind() == Code::LOAD_IC) {
code = NamedLoadHandlerCompiler::ComputeLoadNonexistent(lookup->name(),
receiver_map());
// TODO(jkummerow/verwaest): Introduce a builtin that handles this case.
if (code.is_null()) code = slow_stub();
} else {
code = slow_stub();
}
} else {
if (lookup->state() == LookupIterator::ACCESSOR) {
if (!IsCompatibleReceiver(lookup, receiver_map())) {
TRACE_GENERIC_IC(isolate(), "LoadIC", "incompatible receiver type");
code = slow_stub();
}
} else if (lookup->state() == LookupIterator::INTERCEPTOR) {
// Perform a lookup behind the interceptor. Copy the LookupIterator since
// the original iterator will be used to fetch the value.
LookupIterator it = *lookup;
it.Next();
LookupForRead(&it);
if (it.state() == LookupIterator::ACCESSOR &&
!IsCompatibleReceiver(&it, receiver_map())) {
TRACE_GENERIC_IC(isolate(), "LoadIC", "incompatible receiver type");
code = slow_stub();
}
}
if (code.is_null()) code = ComputeHandler(lookup);
}
PatchCache(lookup->name(), code);
TRACE_IC("LoadIC", lookup->name());
}
void IC::UpdateMegamorphicCache(Map* map, Name* name, Code* code) {
isolate()->stub_cache()->Set(name, map, code);
}
Handle<Code> IC::ComputeHandler(LookupIterator* lookup, Handle<Object> value) {
bool receiver_is_holder =
lookup->GetReceiver().is_identical_to(lookup->GetHolder<JSObject>());
CacheHolderFlag flag;
Handle<Map> stub_holder_map = IC::GetHandlerCacheHolder(
receiver_map(), receiver_is_holder, isolate(), &flag);
Handle<Code> code = PropertyHandlerCompiler::Find(
lookup->name(), stub_holder_map, kind(), flag,
lookup->is_dictionary_holder() ? Code::NORMAL : Code::FAST);
// Use the cached value if it exists, and if it is different from the
// handler that just missed.
if (!code.is_null()) {
if (!maybe_handler_.is_null() &&
!maybe_handler_.ToHandleChecked().is_identical_to(code)) {
return code;
}
if (maybe_handler_.is_null()) {
// maybe_handler_ is only populated for MONOMORPHIC and POLYMORPHIC ICs.
// In MEGAMORPHIC case, check if the handler in the megamorphic stub
// cache (which just missed) is different from the cached handler.
if (state() == MEGAMORPHIC && lookup->GetReceiver()->IsHeapObject()) {
Map* map = Handle<HeapObject>::cast(lookup->GetReceiver())->map();
Code* megamorphic_cached_code =
isolate()->stub_cache()->Get(*lookup->name(), map, code->flags());
if (megamorphic_cached_code != *code) return code;
} else {
return code;
}
}
}
code = CompileHandler(lookup, value, flag);
DCHECK(code->is_handler());
// TODO(mvstanton): we'd only like to cache code on the map when it's custom
// code compiled for this map, otherwise it's already cached in the global
// code
// cache. We are also guarding against installing code with flags that don't
// match the desired CacheHolderFlag computed above, which would lead to
// invalid lookups later.
if (code->type() != Code::NORMAL &&
Code::ExtractCacheHolderFromFlags(code->flags()) == flag) {
Map::UpdateCodeCache(stub_holder_map, lookup->name(), code);
}
return code;
}
Handle<Code> LoadIC::CompileHandler(LookupIterator* lookup,
Handle<Object> unused,
CacheHolderFlag cache_holder) {
Handle<Object> receiver = lookup->GetReceiver();
if (receiver->IsString() &&
Name::Equals(isolate()->factory()->length_string(), lookup->name())) {
FieldIndex index = FieldIndex::ForInObjectOffset(String::kLengthOffset);
return SimpleFieldLoad(index);
}
if (receiver->IsStringWrapper() &&
Name::Equals(isolate()->factory()->length_string(), lookup->name())) {
StringLengthStub string_length_stub(isolate());
return string_length_stub.GetCode();
}
// Use specialized code for getting prototype of functions.
if (receiver->IsJSFunction() &&
Name::Equals(isolate()->factory()->prototype_string(), lookup->name()) &&
receiver->IsConstructor() &&
!Handle<JSFunction>::cast(receiver)
->map()
->has_non_instance_prototype()) {
Handle<Code> stub;
FunctionPrototypeStub function_prototype_stub(isolate());
return function_prototype_stub.GetCode();
}
Handle<Map> map = receiver_map();
Handle<JSObject> holder = lookup->GetHolder<JSObject>();
bool receiver_is_holder = receiver.is_identical_to(holder);
switch (lookup->state()) {
case LookupIterator::INTERCEPTOR: {
DCHECK(!holder->GetNamedInterceptor()->getter()->IsUndefined());
NamedLoadHandlerCompiler compiler(isolate(), map, holder, cache_holder);
// Perform a lookup behind the interceptor. Copy the LookupIterator since
// the original iterator will be used to fetch the value.
LookupIterator it = *lookup;
it.Next();
LookupForRead(&it);
return compiler.CompileLoadInterceptor(&it);
}
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.
int object_offset;
if (Accessors::IsJSObjectFieldAccessor(map, lookup->name(),
&object_offset)) {
FieldIndex index = FieldIndex::ForInObjectOffset(object_offset, *map);
return SimpleFieldLoad(index);
}
if (Accessors::IsJSArrayBufferViewFieldAccessor(map, lookup->name(),
&object_offset)) {
FieldIndex index = FieldIndex::ForInObjectOffset(object_offset, *map);
ArrayBufferViewLoadFieldStub stub(isolate(), index);
return stub.GetCode();
}
if (IsCompatibleReceiver(lookup, map)) {
Handle<Object> accessors = lookup->GetAccessors();
if (accessors->IsAccessorPair()) {
if (!holder->HasFastProperties()) break;
// When debugging we need to go the slow path to flood the accessor.
if (GetSharedFunctionInfo()->HasDebugInfo()) break;
Handle<Object> getter(Handle<AccessorPair>::cast(accessors)->getter(),
isolate());
CallOptimization call_optimization(getter);
NamedLoadHandlerCompiler compiler(isolate(), map, holder,
cache_holder);
if (call_optimization.is_simple_api_call()) {
return compiler.CompileLoadCallback(
lookup->name(), call_optimization, lookup->GetAccessorIndex());
}
int expected_arguments = Handle<JSFunction>::cast(getter)
->shared()
->internal_formal_parameter_count();
return compiler.CompileLoadViaGetter(
lookup->name(), lookup->GetAccessorIndex(), expected_arguments);
} else if (accessors->IsAccessorInfo()) {
Handle<AccessorInfo> info = Handle<AccessorInfo>::cast(accessors);
if (v8::ToCData<Address>(info->getter()) == 0) break;
if (!AccessorInfo::IsCompatibleReceiverMap(isolate(), info, map)) {
// This case should be already handled in LoadIC::UpdateCaches.
UNREACHABLE();
break;
}
if (!holder->HasFastProperties()) break;
NamedLoadHandlerCompiler compiler(isolate(), map, holder,
cache_holder);
return compiler.CompileLoadCallback(lookup->name(), info);
}
}
break;
}
case LookupIterator::DATA: {
if (lookup->is_dictionary_holder()) {
if (kind() != Code::LOAD_IC) break;
if (holder->IsJSGlobalObject()) {
NamedLoadHandlerCompiler compiler(isolate(), map, holder,
cache_holder);
Handle<PropertyCell> cell = lookup->GetPropertyCell();
Handle<Code> code = compiler.CompileLoadGlobal(
cell, lookup->name(), lookup->IsConfigurable());
// TODO(verwaest): Move caching of these NORMAL stubs outside as well.
CacheHolderFlag flag;
Handle<Map> stub_holder_map =
GetHandlerCacheHolder(map, receiver_is_holder, isolate(), &flag);
Map::UpdateCodeCache(stub_holder_map, lookup->name(), code);
return code;
}
// 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 object for the stub to be
// applicable.
if (!receiver_is_holder) break;
return isolate()->builtins()->LoadIC_Normal();
}
// -------------- Fields --------------
if (lookup->property_details().type() == DATA) {
FieldIndex field = lookup->GetFieldIndex();
if (receiver_is_holder) {
return SimpleFieldLoad(field);
}
NamedLoadHandlerCompiler compiler(isolate(), map, holder, cache_holder);
return compiler.CompileLoadField(lookup->name(), field);
}
// -------------- Constant properties --------------
DCHECK(lookup->property_details().type() == DATA_CONSTANT);
if (receiver_is_holder) {
LoadConstantStub stub(isolate(), lookup->GetConstantIndex());
return stub.GetCode();
}
NamedLoadHandlerCompiler compiler(isolate(), map, holder, cache_holder);
return compiler.CompileLoadConstant(lookup->name(),
lookup->GetConstantIndex());
}
case LookupIterator::INTEGER_INDEXED_EXOTIC:
return slow_stub();
case LookupIterator::ACCESS_CHECK:
case LookupIterator::JSPROXY:
case LookupIterator::NOT_FOUND:
case LookupIterator::TRANSITION:
UNREACHABLE();
}
return slow_stub();
}
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->IsUndefined()) {
key = isolate->factory()->undefined_string();
}
return key;
}
Handle<Code> KeyedLoadIC::LoadElementStub(Handle<HeapObject> receiver) {
Handle<Code> null_handle;
Handle<Map> receiver_map(receiver->map(), isolate());
MapHandleList target_receiver_maps;
TargetMaps(&target_receiver_maps);
if (target_receiver_maps.length() == 0) {
Handle<Code> handler =
PropertyICCompiler::ComputeKeyedLoadMonomorphicHandler(
receiver_map, extra_ic_state());
ConfigureVectorState(Handle<Name>::null(), receiver_map, handler);
return null_handle;
}
// 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() &&
IsMoreGeneralElementsKindTransition(
target_receiver_maps.at(0)->elements_kind(),
Handle<JSObject>::cast(receiver)->GetElementsKind())) {
Handle<Code> handler =
PropertyICCompiler::ComputeKeyedLoadMonomorphicHandler(
receiver_map, extra_ic_state());
ConfigureVectorState(Handle<Name>::null(), receiver_map, handler);
return null_handle;
}
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 miss wasn't due to an unseen map, a polymorphic stub
// won't help, use the generic stub.
TRACE_GENERIC_IC(isolate(), "KeyedLoadIC", "same map added twice");
return megamorphic_stub();
}
// If the maximum number of receiver maps has been exceeded, use the generic
// version of the IC.
if (target_receiver_maps.length() > kMaxKeyedPolymorphism) {
TRACE_GENERIC_IC(isolate(), "KeyedLoadIC", "max polymorph exceeded");
return megamorphic_stub();
}
CodeHandleList handlers(target_receiver_maps.length());
ElementHandlerCompiler compiler(isolate());
compiler.CompileElementHandlers(&target_receiver_maps, &handlers);
ConfigureVectorState(Handle<Name>::null(), &target_receiver_maps, &handlers);
return null_handle;
}
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;
Handle<Code> stub = megamorphic_stub();
// Check for non-string values that can be converted into an
// internalized string directly or is representable as a smi.
key = TryConvertKey(key, isolate());
if (key->IsInternalizedString() || 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->IsJSObject() || (object->IsString() && key->IsNumber())) {
Handle<HeapObject> receiver = Handle<HeapObject>::cast(object);
if (object->IsString() || key->IsSmi()) stub = LoadElementStub(receiver);
}
}
DCHECK(UseVector());
if (!is_vector_set() || stub.is_null()) {
Code* generic = *megamorphic_stub();
if (!stub.is_null() && *stub == generic) {
ConfigureVectorState(MEGAMORPHIC, key);
TRACE_GENERIC_IC(isolate(), "KeyedLoadIC", "set generic");
}
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->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 false;
case LookupIterator::INTERCEPTOR: {
Handle<JSObject> holder = it->GetHolder<JSObject>();
InterceptorInfo* info = holder->GetNamedInterceptor();
if (it->HolderIsReceiverOrHiddenPrototype()) {
if (!info->setter()->IsUndefined()) return true;
} else if (!info->getter()->IsUndefined() ||
!info->query()->IsUndefined()) {
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;
it->PrepareTransitionToDataProperty(receiver, value, NONE, store_mode);
return it->IsCacheableTransition();
}
}
}
receiver = it->GetStoreTarget();
if (it->ExtendingNonExtensible(receiver)) return false;
it->PrepareTransitionToDataProperty(receiver, value, NONE, store_mode);
return it->IsCacheableTransition();
}
MaybeHandle<Object> StoreIC::Store(Handle<Object> object, Handle<Name> name,
Handle<Object> value,
JSReceiver::StoreFromKeyed store_mode) {
// Check if the name is trivially convertible to an index and set the element.
uint32_t index;
if (kind() == Code::KEYED_STORE_IC && name->AsArrayIndex(&index)) {
// Rewrite to the generic keyed store stub.
if (FLAG_use_ic) {
if (UseVector()) {
ConfigureVectorState(MEGAMORPHIC, name);
} else if (!AddressIsDeoptimizedCode()) {
set_target(*megamorphic_stub());
}
TRACE_IC("StoreIC", name);
TRACE_GENERIC_IC(isolate(), "StoreIC", "name as array index");
}
Handle<Object> result;
ASSIGN_RETURN_ON_EXCEPTION(
isolate(), result,
Object::SetElement(isolate(), object, index, value, language_mode()),
Object);
return result;
}
if (object->IsJSGlobalObject() && name->IsString()) {
// Look up in script context table.
Handle<String> str_name = Handle<String>::cast(name);
Handle<JSGlobalObject> global = Handle<JSGlobalObject>::cast(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, object, name);
}
Handle<Object> previous_value =
FixedArray::get(*script_context, lookup_result.slot_index, isolate());
if (*previous_value == *isolate()->factory()->the_hole_value()) {
// Do not install stubs and stay pre-monomorphic for
// uninitialized accesses.
return ReferenceError(name);
}
if (FLAG_use_ic &&
StoreScriptContextFieldStub::Accepted(&lookup_result)) {
StoreScriptContextFieldStub stub(isolate(), &lookup_result);
PatchCache(name, stub.GetCode());
}
script_context->set(lookup_result.slot_index, *value);
return 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) || object->IsJSProxy()) {
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->IsUndefined() || object->IsNull()) {
return TypeError(MessageTemplate::kNonObjectPropertyStore, object, name);
}
// Observed objects are always modified through the runtime.
if (object->IsHeapObject() &&
Handle<HeapObject>::cast(object)->map()->is_observed()) {
Handle<Object> result;
ASSIGN_RETURN_ON_EXCEPTION(
isolate(), result,
Object::SetProperty(object, name, value, language_mode(), store_mode),
Object);
return result;
}
LookupIterator it(object, name);
if (FLAG_use_ic) UpdateCaches(&it, value, store_mode);
MAYBE_RETURN_NULL(
Object::SetProperty(&it, value, language_mode(), store_mode));
return value;
}
Handle<Code> CallIC::initialize_stub(Isolate* isolate, int argc,
ConvertReceiverMode mode,
TailCallMode tail_call_mode) {
CallICTrampolineStub stub(isolate, CallICState(argc, mode, tail_call_mode));
Handle<Code> code = stub.GetCode();
return code;
}
Handle<Code> CallIC::initialize_stub_in_optimized_code(
Isolate* isolate, int argc, ConvertReceiverMode mode,
TailCallMode tail_call_mode) {
CallICStub stub(isolate, CallICState(argc, mode, tail_call_mode));
Handle<Code> code = stub.GetCode();
return code;
}
static Handle<Code> StoreICInitializeStubHelper(
Isolate* isolate, ExtraICState extra_state,
InlineCacheState initialization_state) {
Handle<Code> ic = PropertyICCompiler::ComputeStore(
isolate, initialization_state, extra_state);
return ic;
}
Handle<Code> StoreIC::initialize_stub(Isolate* isolate,
LanguageMode language_mode,
State initialization_state) {
DCHECK(initialization_state == UNINITIALIZED ||
initialization_state == PREMONOMORPHIC ||
initialization_state == MEGAMORPHIC);
VectorStoreICTrampolineStub stub(isolate, StoreICState(language_mode));
return stub.GetCode();
}
Handle<Code> StoreIC::initialize_stub_in_optimized_code(
Isolate* isolate, LanguageMode language_mode, State initialization_state) {
DCHECK(initialization_state == UNINITIALIZED ||
initialization_state == PREMONOMORPHIC ||
initialization_state == MEGAMORPHIC);
if (initialization_state != MEGAMORPHIC) {
VectorStoreICStub stub(isolate, StoreICState(language_mode));
return stub.GetCode();
}
return StoreICInitializeStubHelper(
isolate, ComputeExtraICState(language_mode), initialization_state);
}
Handle<Code> StoreIC::megamorphic_stub() {
if (kind() == Code::STORE_IC) {
return PropertyICCompiler::ComputeStore(isolate(), MEGAMORPHIC,
extra_ic_state());
} else {
DCHECK(kind() == Code::KEYED_STORE_IC);
if (is_strict(language_mode())) {
return isolate()->builtins()->KeyedStoreIC_Megamorphic_Strict();
} else {
return isolate()->builtins()->KeyedStoreIC_Megamorphic();
}
}
}
Handle<Code> StoreIC::slow_stub() const {
if (kind() == Code::STORE_IC) {
return isolate()->builtins()->StoreIC_Slow();
} else {
DCHECK(kind() == Code::KEYED_STORE_IC);
return isolate()->builtins()->KeyedStoreIC_Slow();
}
}
Handle<Code> StoreIC::pre_monomorphic_stub(Isolate* isolate,
LanguageMode language_mode) {
ExtraICState state = ComputeExtraICState(language_mode);
return PropertyICCompiler::ComputeStore(isolate, PREMONOMORPHIC, state);
}
void StoreIC::UpdateCaches(LookupIterator* lookup, Handle<Object> value,
JSReceiver::StoreFromKeyed store_mode) {
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.
ConfigureVectorState(PREMONOMORPHIC, Handle<Object>());
TRACE_IC("StoreIC", lookup->name());
return;
}
bool use_ic = LookupForWrite(lookup, value, store_mode);
if (!use_ic) {
TRACE_GENERIC_IC(isolate(), "StoreIC", "LookupForWrite said 'false'");
}
Handle<Code> code = use_ic ? ComputeHandler(lookup, value) : slow_stub();
PatchCache(lookup->name(), code);
TRACE_IC("StoreIC", lookup->name());
}
static Handle<Code> PropertyCellStoreHandler(
Isolate* isolate, Handle<JSObject> receiver, Handle<JSGlobalObject> holder,
Handle<Name> name, Handle<PropertyCell> cell, PropertyCellType type) {
auto constant_type = Nothing<PropertyCellConstantType>();
if (type == PropertyCellType::kConstantType) {
constant_type = Just(cell->GetConstantType());
}
StoreGlobalStub stub(isolate, type, constant_type,
receiver->IsJSGlobalProxy());
auto code = stub.GetCodeCopyFromTemplate(holder, cell);
// TODO(verwaest): Move caching of these NORMAL stubs outside as well.
HeapObject::UpdateMapCodeCache(receiver, name, code);
return code;
}
Handle<Code> StoreIC::CompileHandler(LookupIterator* lookup,
Handle<Object> value,
CacheHolderFlag cache_holder) {
DCHECK_NE(LookupIterator::JSPROXY, lookup->state());
// 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());
switch (lookup->state()) {
case LookupIterator::TRANSITION: {
auto store_target = lookup->GetStoreTarget();
if (store_target->IsJSGlobalObject()) {
// TODO(dcarney): this currently just deopts. Use the transition cell.
auto cell = isolate()->factory()->NewPropertyCell();
cell->set_value(*value);
auto code = PropertyCellStoreHandler(
isolate(), store_target, Handle<JSGlobalObject>::cast(store_target),
lookup->name(), cell, PropertyCellType::kConstant);
cell->set_value(isolate()->heap()->the_hole_value());
return code;
}
Handle<Map> transition = lookup->transition_map();
// Currently not handled by CompileStoreTransition.
if (!holder->HasFastProperties()) {
TRACE_GENERIC_IC(isolate(), "StoreIC", "transition from slow");
break;
}
DCHECK(lookup->IsCacheableTransition());
NamedStoreHandlerCompiler compiler(isolate(), receiver_map(), holder);
return compiler.CompileStoreTransition(transition, lookup->name());
}
case LookupIterator::INTERCEPTOR: {
DCHECK(!holder->GetNamedInterceptor()->setter()->IsUndefined());
NamedStoreHandlerCompiler compiler(isolate(), receiver_map(), holder);
return compiler.CompileStoreInterceptor(lookup->name());
}
case LookupIterator::ACCESSOR: {
if (!holder->HasFastProperties()) {
TRACE_GENERIC_IC(isolate(), "StoreIC", "accessor on slow map");
break;
}
Handle<Object> accessors = lookup->GetAccessors();
if (accessors->IsAccessorInfo()) {
Handle<AccessorInfo> info = Handle<AccessorInfo>::cast(accessors);
if (v8::ToCData<Address>(info->setter()) == 0) {
TRACE_GENERIC_IC(isolate(), "StoreIC", "setter == 0");
break;
}
if (AccessorInfo::cast(*accessors)->is_special_data_property() &&
!lookup->HolderIsReceiverOrHiddenPrototype()) {
TRACE_GENERIC_IC(isolate(), "StoreIC",
"special data property in prototype chain");
break;
}
if (!AccessorInfo::IsCompatibleReceiverMap(isolate(), info,
receiver_map())) {
TRACE_GENERIC_IC(isolate(), "StoreIC", "incompatible receiver type");
break;
}
NamedStoreHandlerCompiler compiler(isolate(), receiver_map(), holder);
return compiler.CompileStoreCallback(receiver, lookup->name(), info,
language_mode());
} else if (accessors->IsAccessorPair()) {
Handle<Object> setter(Handle<AccessorPair>::cast(accessors)->setter(),
isolate());
if (!setter->IsJSFunction()) {
TRACE_GENERIC_IC(isolate(), "StoreIC", "setter not a function");
break;
}
Handle<JSFunction> function = Handle<JSFunction>::cast(setter);
CallOptimization call_optimization(function);
NamedStoreHandlerCompiler compiler(isolate(), receiver_map(), holder);
if (call_optimization.is_simple_api_call() &&
call_optimization.IsCompatibleReceiver(receiver, holder)) {
return compiler.CompileStoreCallback(receiver, lookup->name(),
call_optimization,
lookup->GetAccessorIndex());
}
int expected_arguments =
function->shared()->internal_formal_parameter_count();
return compiler.CompileStoreViaSetter(receiver, lookup->name(),
lookup->GetAccessorIndex(),
expected_arguments);
}
break;
}
case LookupIterator::DATA: {
if (lookup->is_dictionary_holder()) {
if (holder->IsJSGlobalObject()) {
DCHECK(holder.is_identical_to(receiver) ||
receiver->map()->prototype() == *holder);
auto cell = lookup->GetPropertyCell();
auto updated_type = PropertyCell::UpdatedType(
cell, value, lookup->property_details());
auto code = PropertyCellStoreHandler(
isolate(), receiver, Handle<JSGlobalObject>::cast(holder),
lookup->name(), cell, updated_type);
return code;
}
DCHECK(holder.is_identical_to(receiver));
return isolate()->builtins()->StoreIC_Normal();
}
// -------------- Fields --------------
if (lookup->property_details().type() == DATA) {
bool use_stub = true;
if (lookup->representation().IsHeapObject()) {
// Only use a generic stub if no types need to be tracked.
Handle<FieldType> field_type = lookup->GetFieldType();
use_stub = !field_type->IsClass();
}
if (use_stub) {
StoreFieldStub stub(isolate(), lookup->GetFieldIndex(),
lookup->representation());
return stub.GetCode();
}
NamedStoreHandlerCompiler compiler(isolate(), receiver_map(), holder);
return compiler.CompileStoreField(lookup);
}
// -------------- Constant properties --------------
DCHECK(lookup->property_details().type() == DATA_CONSTANT);
TRACE_GENERIC_IC(isolate(), "StoreIC", "constant property");
break;
}
case LookupIterator::INTEGER_INDEXED_EXOTIC:
case LookupIterator::ACCESS_CHECK:
case LookupIterator::JSPROXY:
case LookupIterator::NOT_FOUND:
UNREACHABLE();
}
return slow_stub();
}
Handle<Code> KeyedStoreIC::StoreElementStub(Handle<Map> receiver_map,
KeyedAccessStoreMode store_mode) {
Handle<Code> null_handle;
// Don't handle megamorphic property accesses for INTERCEPTORS or
// ACCESSOR_CONSTANT
// via megamorphic stubs, since they don't have a map in their relocation info
// and so the stubs can't be harvested for the object needed for a map check.
if (target()->type() != Code::NORMAL) {
TRACE_GENERIC_IC(isolate(), "KeyedStoreIC", "non-NORMAL target type");
return megamorphic_stub();
}
MapHandleList target_receiver_maps;
TargetMaps(&target_receiver_maps);
if (target_receiver_maps.length() == 0) {
Handle<Map> monomorphic_map =
ComputeTransitionedMap(receiver_map, store_mode);
store_mode = GetNonTransitioningStoreMode(store_mode);
Handle<Code> handler =
PropertyICCompiler::ComputeKeyedStoreMonomorphicHandler(
monomorphic_map, language_mode(), store_mode);
ConfigureVectorState(Handle<Name>::null(), monomorphic_map, handler);
return null_handle;
}
// 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 = 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<Code> handler =
PropertyICCompiler::ComputeKeyedStoreMonomorphicHandler(
transitioned_receiver_map, language_mode(), store_mode);
ConfigureVectorState(Handle<Name>::null(), transitioned_receiver_map,
handler);
return null_handle;
} else 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<Code> handler =
PropertyICCompiler::ComputeKeyedStoreMonomorphicHandler(
receiver_map, language_mode(), store_mode);
ConfigureVectorState(Handle<Name>::null(), receiver_map, handler);
return null_handle;
}
}
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(isolate(), "KeyedStoreIC", "same map added twice");
return megamorphic_stub();
}
// If the maximum number of receiver maps has been exceeded, use the
// megamorphic version of the IC.
if (target_receiver_maps.length() > kMaxKeyedPolymorphism) {
return megamorphic_stub();
}
// 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(isolate(), "KeyedStoreIC", "store mode mismatch");
return megamorphic_stub();
}
}
// 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) {
int external_arrays = 0;
for (int i = 0; i < target_receiver_maps.length(); ++i) {
if (target_receiver_maps[i]->has_fixed_typed_array_elements()) {
external_arrays++;
}
}
if (external_arrays != 0 &&
external_arrays != target_receiver_maps.length()) {
TRACE_GENERIC_IC(isolate(), "KeyedStoreIC",
"unsupported combination of external and normal arrays");
return megamorphic_stub();
}
}
MapHandleList transitioned_maps(target_receiver_maps.length());
CodeHandleList handlers(target_receiver_maps.length());
PropertyICCompiler::ComputeKeyedStorePolymorphicHandlers(
&target_receiver_maps, &transitioned_maps, &handlers, store_mode,
language_mode());
ConfigureVectorState(&target_receiver_maps, &transitioned_maps, &handlers);
return null_handle;
}
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 = IsFastHoleyElementsKind(map->elements_kind())
? FAST_HOLEY_ELEMENTS
: FAST_ELEMENTS;
return Map::TransitionElementsTo(map, kind);
}
case STORE_TRANSITION_TO_DOUBLE:
case STORE_AND_GROW_TRANSITION_TO_DOUBLE: {
ElementsKind kind = IsFastHoleyElementsKind(map->elements_kind())
? FAST_HOLEY_DOUBLE_ELEMENTS
: FAST_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();
return MaybeHandle<Map>().ToHandleChecked();
}
bool IsOutOfBoundsAccess(Handle<JSObject> receiver, uint32_t index) {
uint32_t length = 0;
if (receiver->IsJSArray()) {
JSArray::cast(*receiver)->length()->ToArrayLength(&length);
} else {
length = static_cast<uint32_t>(receiver->elements()->length());
}
return index >= length;
}
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->HasFastSmiElements()) {
if (value->IsHeapNumber()) {
return STORE_AND_GROW_TRANSITION_TO_DOUBLE;
}
if (value->IsHeapObject()) {
return STORE_AND_GROW_TRANSITION_TO_OBJECT;
}
} else if (receiver->HasFastDoubleElements()) {
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->HasFastSmiElements()) {
if (value->IsHeapNumber()) {
return STORE_TRANSITION_TO_DOUBLE;
} else if (value->IsHeapObject()) {
return STORE_TRANSITION_TO_OBJECT;
}
} else if (receiver->HasFastDoubleElements()) {
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;
Handle<Code> stub = megamorphic_stub();
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 (!is_vector_set()) {
ConfigureVectorState(MEGAMORPHIC, key);
TRACE_GENERIC_IC(isolate(), "KeyedStoreIC",
"unhandled internalized string key");
TRACE_IC("StoreIC", key);
}
return store_handle;
}
bool use_ic =
FLAG_use_ic && !object->IsStringWrapper() &&
!object->IsAccessCheckNeeded() && !object->IsJSGlobalProxy() &&
!(object->IsJSObject() && JSObject::cast(*object)->map()->is_observed());
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(isolate(), "KeyedStoreIC", "map in array prototype");
use_ic = false;
}
}
Handle<Map> old_receiver_map;
bool sloppy_arguments_elements = false;
bool key_is_valid_index = false;
KeyedAccessStoreMode store_mode = STANDARD_STORE;
if (use_ic && object->IsJSObject()) {
Handle<JSObject> receiver = Handle<JSObject>::cast(object);
old_receiver_map = handle(receiver->map(), isolate());
sloppy_arguments_elements =
!is_sloppy(language_mode()) &&
receiver->elements()->map() ==
isolate()->heap()->sloppy_arguments_elements_map();
if (!sloppy_arguments_elements) {
key_is_valid_index = key->IsSmi() && Smi::cast(*key)->value() >= 0;
if (key_is_valid_index) {
uint32_t index = static_cast<uint32_t>(Smi::cast(*key)->value());
store_mode = GetStoreMode(receiver, 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 (sloppy_arguments_elements) {
TRACE_GENERIC_IC(isolate(), "KeyedStoreIC", "arguments receiver");
} else if (key_is_valid_index) {
// 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.
if (!old_receiver_map->DictionaryElementsInPrototypeChainOnly()) {
stub = StoreElementStub(old_receiver_map, store_mode);
} else {
TRACE_GENERIC_IC(isolate(), "KeyedStoreIC",
"dictionary or proxy prototype");
}
} else {
TRACE_GENERIC_IC(isolate(), "KeyedStoreIC", "non-smi-like key");
}
} else {
TRACE_GENERIC_IC(isolate(), "KeyedStoreIC", "non-JSObject receiver");
}
}
if (!is_vector_set() || stub.is_null()) {
Code* megamorphic = *megamorphic_stub();
if (!stub.is_null() && (*stub == megamorphic || *stub == *slow_stub())) {
ConfigureVectorState(MEGAMORPHIC, key);
TRACE_GENERIC_IC(isolate(), "KeyedStoreIC",
*stub == megamorphic ? "set generic" : "slow stub");
}
}
TRACE_IC("StoreIC", key);
return store_handle;
}
void CallIC::HandleMiss(Handle<Object> function) {
Handle<Object> name = isolate()->factory()->empty_string();
CallICNexus* nexus = casted_nexus<CallICNexus>();
Object* feedback = nexus->GetFeedback();
// Hand-coded MISS handling is easier if CallIC slots don't contain smis.
DCHECK(!feedback->IsSmi());
if (feedback->IsWeakCell() || !function->IsJSFunction() ||
feedback->IsAllocationSite()) {
// We are going generic.
nexus->ConfigureMegamorphic();
} else {
DCHECK(feedback == *TypeFeedbackVector::UninitializedSentinel(isolate()));
Handle<JSFunction> js_function = Handle<JSFunction>::cast(function);
Handle<JSFunction> array_function =
Handle<JSFunction>(isolate()->native_context()->array_function());
if (array_function.is_identical_to(js_function)) {
// Alter the slot.
nexus->ConfigureMonomorphicArray();
} else if (js_function->context()->native_context() !=
*isolate()->native_context()) {
// Don't collect cross-native context feedback for the CallIC.
// TODO(bmeurer): We should collect the SharedFunctionInfo as
// feedback in this case instead.
nexus->ConfigureMegamorphic();
} else {
nexus->ConfigureMonomorphic(js_function);
}
}
if (function->IsJSFunction()) {
Handle<JSFunction> js_function = Handle<JSFunction>::cast(function);
name = handle(js_function->shared()->name(), isolate());
}
OnTypeFeedbackChanged(isolate(), get_host());
TRACE_IC("CallIC", name);
}
#undef TRACE_IC
// ----------------------------------------------------------------------------
// Static IC stub generators.
//
// Used from ic-<arch>.cc.
RUNTIME_FUNCTION(Runtime_CallIC_Miss) {
TimerEventScope<TimerEventIcMiss> timer(isolate);
TRACE_EVENT0(TRACE_DISABLED_BY_DEFAULT("v8"), "V8.IcMiss");
HandleScope scope(isolate);
DCHECK(args.length() == 3);
Handle<Object> function = args.at<Object>(0);
Handle<TypeFeedbackVector> vector = args.at<TypeFeedbackVector>(1);
Handle<Smi> slot = args.at<Smi>(2);
FeedbackVectorSlot vector_slot = vector->ToSlot(slot->value());
CallICNexus nexus(vector, vector_slot);
CallIC ic(isolate, &nexus);
ic.HandleMiss(function);
return *function;
}
// Used from ic-<arch>.cc.
RUNTIME_FUNCTION(Runtime_LoadIC_Miss) {
TimerEventScope<TimerEventIcMiss> timer(isolate);
TRACE_EVENT0(TRACE_DISABLED_BY_DEFAULT("v8"), "V8.IcMiss");
HandleScope scope(isolate);
Handle<Object> receiver = args.at<Object>(0);
Handle<Name> key = args.at<Name>(1);
Handle<Object> result;
DCHECK(args.length() == 4);
Handle<Smi> slot = args.at<Smi>(2);
Handle<TypeFeedbackVector> vector = args.at<TypeFeedbackVector>(3);
FeedbackVectorSlot 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.
if (vector->GetKind(vector_slot) == FeedbackVectorSlotKind::LOAD_IC) {
LoadICNexus nexus(vector, vector_slot);
LoadIC ic(IC::NO_EXTRA_FRAME, isolate, &nexus);
ic.UpdateState(receiver, key);
ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, result, ic.Load(receiver, key));
} else {
DCHECK_EQ(FeedbackVectorSlotKind::KEYED_LOAD_IC,
vector->GetKind(vector_slot));
KeyedLoadICNexus nexus(vector, vector_slot);
KeyedLoadIC ic(IC::NO_EXTRA_FRAME, isolate, &nexus);
ic.UpdateState(receiver, key);
ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, result, ic.Load(receiver, key));
}
return *result;
}
// Used from ic-<arch>.cc
RUNTIME_FUNCTION(Runtime_KeyedLoadIC_Miss) {
TimerEventScope<TimerEventIcMiss> timer(isolate);
TRACE_EVENT0(TRACE_DISABLED_BY_DEFAULT("v8"), "V8.IcMiss");
HandleScope scope(isolate);
Handle<Object> receiver = args.at<Object>(0);
Handle<Object> key = args.at<Object>(1);
Handle<Object> result;
DCHECK(args.length() == 4);
Handle<Smi> slot = args.at<Smi>(2);
Handle<TypeFeedbackVector> vector = args.at<TypeFeedbackVector>(3);
FeedbackVectorSlot vector_slot = vector->ToSlot(slot->value());
KeyedLoadICNexus nexus(vector, vector_slot);
KeyedLoadIC ic(IC::NO_EXTRA_FRAME, isolate, &nexus);
ic.UpdateState(receiver, key);
ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, result, ic.Load(receiver, key));
return *result;
}
RUNTIME_FUNCTION(Runtime_KeyedLoadIC_MissFromStubFailure) {
TimerEventScope<TimerEventIcMiss> timer(isolate);
TRACE_EVENT0(TRACE_DISABLED_BY_DEFAULT("v8"), "V8.IcMiss");
HandleScope scope(isolate);
Handle<Object> receiver = args.at<Object>(0);
Handle<Object> key = args.at<Object>(1);
Handle<Object> result;
DCHECK(args.length() == 4);
Handle<Smi> slot = args.at<Smi>(2);
Handle<TypeFeedbackVector> vector = args.at<TypeFeedbackVector>(3);
FeedbackVectorSlot vector_slot = vector->ToSlot(slot->value());
KeyedLoadICNexus nexus(vector, vector_slot);
KeyedLoadIC ic(IC::EXTRA_CALL_FRAME, isolate, &nexus);
ic.UpdateState(receiver, key);
ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, result, ic.Load(receiver, key));
return *result;
}
// Used from ic-<arch>.cc.
RUNTIME_FUNCTION(Runtime_StoreIC_Miss) {
TimerEventScope<TimerEventIcMiss> timer(isolate);
TRACE_EVENT0(TRACE_DISABLED_BY_DEFAULT("v8"), "V8.IcMiss");
HandleScope scope(isolate);
Handle<Object> receiver = args.at<Object>(0);
Handle<Name> key = args.at<Name>(1);
Handle<Object> value = args.at<Object>(2);
Handle<Object> result;
DCHECK(args.length() == 5 || args.length() == 6);
Handle<Smi> slot = args.at<Smi>(3);
Handle<TypeFeedbackVector> vector = args.at<TypeFeedbackVector>(4);
FeedbackVectorSlot vector_slot = vector->ToSlot(slot->value());
if (vector->GetKind(vector_slot) == FeedbackVectorSlotKind::STORE_IC) {
StoreICNexus nexus(vector, vector_slot);
StoreIC ic(IC::NO_EXTRA_FRAME, isolate, &nexus);
ic.UpdateState(receiver, key);
ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, result,
ic.Store(receiver, key, value));
} else {
DCHECK_EQ(FeedbackVectorSlotKind::KEYED_STORE_IC,
vector->GetKind(vector_slot));
KeyedStoreICNexus nexus(vector, vector_slot);
KeyedStoreIC ic(IC::NO_EXTRA_FRAME, isolate, &nexus);
ic.UpdateState(receiver, key);
ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, result,
ic.Store(receiver, key, value));
}
return *result;
}
RUNTIME_FUNCTION(Runtime_StoreIC_MissFromStubFailure) {
TimerEventScope<TimerEventIcMiss> timer(isolate);
TRACE_EVENT0(TRACE_DISABLED_BY_DEFAULT("v8"), "V8.IcMiss");
HandleScope scope(isolate);
Handle<Object> receiver = args.at<Object>(0);
Handle<Name> key = args.at<Name>(1);
Handle<Object> value = args.at<Object>(2);
Handle<Object> result;
int length = args.length();
DCHECK(length == 5 || length == 6);
// We might have slot and vector, for a normal miss (slot(3), vector(4)).
// Or, map and vector for a transitioning store miss (map(3), vector(4)).
// In this case, we need to recover the slot from a virtual register.
// If length == 6, then a map is included (map(3), slot(4), vector(5)).
Handle<Smi> slot;
Handle<TypeFeedbackVector> vector;
if (length == 5) {
if (args.at<Object>(3)->IsMap()) {
vector = args.at<TypeFeedbackVector>(4);
slot = handle(
*reinterpret_cast<Smi**>(isolate->virtual_slot_register_address()),
isolate);
} else {
vector = args.at<TypeFeedbackVector>(4);
slot = args.at<Smi>(3);
}
} else {
vector = args.at<TypeFeedbackVector>(5);
slot = args.at<Smi>(4);
}
FeedbackVectorSlot vector_slot = vector->ToSlot(slot->value());
if (vector->GetKind(vector_slot) == FeedbackVectorSlotKind::STORE_IC) {
StoreICNexus nexus(vector, vector_slot);
StoreIC ic(IC::EXTRA_CALL_FRAME, isolate, &nexus);
ic.UpdateState(receiver, key);
ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, result,
ic.Store(receiver, key, value));
} else {
DCHECK_EQ(FeedbackVectorSlotKind::KEYED_STORE_IC,
vector->GetKind(vector_slot));
KeyedStoreICNexus nexus(vector, vector_slot);
KeyedStoreIC ic(IC::EXTRA_CALL_FRAME, isolate, &nexus);
ic.UpdateState(receiver, key);
ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, result,
ic.Store(receiver, key, value));
}
return *result;
}
// Used from ic-<arch>.cc.
RUNTIME_FUNCTION(Runtime_KeyedStoreIC_Miss) {
TimerEventScope<TimerEventIcMiss> timer(isolate);
TRACE_EVENT0(TRACE_DISABLED_BY_DEFAULT("v8"), "V8.IcMiss");
HandleScope scope(isolate);
Handle<Object> receiver = args.at<Object>(0);
Handle<Object> key = args.at<Object>(1);
Handle<Object> value = args.at<Object>(2);
Handle<Object> result;
DCHECK(args.length() == 5);
Handle<Smi> slot = args.at<Smi>(3);
Handle<TypeFeedbackVector> vector = args.at<TypeFeedbackVector>(4);
FeedbackVectorSlot vector_slot = vector->ToSlot(slot->value());
KeyedStoreICNexus nexus(vector, vector_slot);
KeyedStoreIC ic(IC::NO_EXTRA_FRAME, isolate, &nexus);
ic.UpdateState(receiver, key);
ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, result,
ic.Store(receiver, key, value));
return *result;
}
RUNTIME_FUNCTION(Runtime_KeyedStoreIC_MissFromStubFailure) {
TimerEventScope<TimerEventIcMiss> timer(isolate);
TRACE_EVENT0(TRACE_DISABLED_BY_DEFAULT("v8"), "V8.IcMiss");
HandleScope scope(isolate);
Handle<Object> receiver = args.at<Object>(0);
Handle<Object> key = args.at<Object>(1);
Handle<Object> value = args.at<Object>(2);
Handle<Object> result;
DCHECK(args.length() == 5);
Handle<Smi> slot = args.at<Smi>(3);
Handle<TypeFeedbackVector> vector = args.at<TypeFeedbackVector>(4);
FeedbackVectorSlot vector_slot = vector->ToSlot(slot->value());
KeyedStoreICNexus nexus(vector, vector_slot);
KeyedStoreIC ic(IC::EXTRA_CALL_FRAME, isolate, &nexus);
ic.UpdateState(receiver, key);
ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, result,
ic.Store(receiver, key, value));
return *result;
}
RUNTIME_FUNCTION(Runtime_StoreIC_Slow) {
HandleScope scope(isolate);
DCHECK(args.length() == 5);
Handle<Object> object = args.at<Object>(0);
Handle<Object> key = args.at<Object>(1);
Handle<Object> value = args.at<Object>(2);
LanguageMode language_mode;
StoreICNexus nexus(isolate);
StoreIC ic(IC::NO_EXTRA_FRAME, isolate, &nexus);
language_mode = ic.language_mode();