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feedback-vector.cc
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feedback-vector.cc
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// Copyright 2014 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/feedback-vector.h"
#include "src/code-stubs.h"
#include "src/feedback-vector-inl.h"
#include "src/ic/ic-inl.h"
#include "src/objects.h"
#include "src/objects/hash-table-inl.h"
#include "src/objects/object-macros.h"
namespace v8 {
namespace internal {
FeedbackSlot FeedbackVectorSpec::AddSlot(FeedbackSlotKind kind) {
int slot = slots();
int entries_per_slot = FeedbackMetadata::GetSlotSize(kind);
append(kind);
for (int i = 1; i < entries_per_slot; i++) {
append(FeedbackSlotKind::kInvalid);
}
return FeedbackSlot(slot);
}
FeedbackSlot FeedbackVectorSpec::AddTypeProfileSlot() {
FeedbackSlot slot = AddSlot(FeedbackSlotKind::kTypeProfile);
CHECK_EQ(FeedbackVectorSpec::kTypeProfileSlotIndex,
FeedbackVector::GetIndex(slot));
return slot;
}
bool FeedbackVectorSpec::HasTypeProfileSlot() const {
FeedbackSlot slot =
FeedbackVector::ToSlot(FeedbackVectorSpec::kTypeProfileSlotIndex);
if (slots() <= slot.ToInt()) {
return false;
}
return GetKind(slot) == FeedbackSlotKind::kTypeProfile;
}
static bool IsPropertyNameFeedback(MaybeObject* feedback) {
HeapObject* heap_object;
if (!feedback->ToStrongHeapObject(&heap_object)) return false;
if (heap_object->IsString()) return true;
if (!heap_object->IsSymbol()) return false;
Symbol* symbol = Symbol::cast(heap_object);
ReadOnlyRoots roots = symbol->GetReadOnlyRoots();
return symbol != roots.uninitialized_symbol() &&
symbol != roots.premonomorphic_symbol() &&
symbol != roots.megamorphic_symbol();
}
std::ostream& operator<<(std::ostream& os, FeedbackSlotKind kind) {
return os << FeedbackMetadata::Kind2String(kind);
}
FeedbackSlotKind FeedbackMetadata::GetKind(FeedbackSlot slot) const {
int index = VectorICComputer::index(0, slot.ToInt());
int data = get(index);
return VectorICComputer::decode(data, slot.ToInt());
}
void FeedbackMetadata::SetKind(FeedbackSlot slot, FeedbackSlotKind kind) {
int index = VectorICComputer::index(0, slot.ToInt());
int data = get(index);
int new_data = VectorICComputer::encode(data, slot.ToInt(), kind);
set(index, new_data);
}
// static
Handle<FeedbackMetadata> FeedbackMetadata::New(Isolate* isolate,
const FeedbackVectorSpec* spec) {
Factory* factory = isolate->factory();
const int slot_count = spec == nullptr ? 0 : spec->slots();
if (slot_count == 0) {
return factory->empty_feedback_metadata();
}
#ifdef DEBUG
for (int i = 0; i < slot_count;) {
DCHECK(spec);
FeedbackSlotKind kind = spec->GetKind(FeedbackSlot(i));
int entry_size = FeedbackMetadata::GetSlotSize(kind);
for (int j = 1; j < entry_size; j++) {
FeedbackSlotKind kind = spec->GetKind(FeedbackSlot(i + j));
DCHECK_EQ(FeedbackSlotKind::kInvalid, kind);
}
i += entry_size;
}
#endif
Handle<FeedbackMetadata> metadata = factory->NewFeedbackMetadata(slot_count);
// Initialize the slots. The raw data section has already been pre-zeroed in
// NewFeedbackMetadata.
for (int i = 0; i < slot_count; i++) {
DCHECK(spec);
FeedbackSlot slot(i);
FeedbackSlotKind kind = spec->GetKind(slot);
metadata->SetKind(slot, kind);
}
return metadata;
}
bool FeedbackMetadata::SpecDiffersFrom(
const FeedbackVectorSpec* other_spec) const {
if (other_spec->slots() != slot_count()) {
return true;
}
int slots = slot_count();
for (int i = 0; i < slots;) {
FeedbackSlot slot(i);
FeedbackSlotKind kind = GetKind(slot);
int entry_size = FeedbackMetadata::GetSlotSize(kind);
if (kind != other_spec->GetKind(slot)) {
return true;
}
i += entry_size;
}
return false;
}
const char* FeedbackMetadata::Kind2String(FeedbackSlotKind kind) {
switch (kind) {
case FeedbackSlotKind::kInvalid:
return "Invalid";
case FeedbackSlotKind::kCall:
return "Call";
case FeedbackSlotKind::kLoadProperty:
return "LoadProperty";
case FeedbackSlotKind::kLoadGlobalInsideTypeof:
return "LoadGlobalInsideTypeof";
case FeedbackSlotKind::kLoadGlobalNotInsideTypeof:
return "LoadGlobalNotInsideTypeof";
case FeedbackSlotKind::kLoadKeyed:
return "LoadKeyed";
case FeedbackSlotKind::kStoreNamedSloppy:
return "StoreNamedSloppy";
case FeedbackSlotKind::kStoreNamedStrict:
return "StoreNamedStrict";
case FeedbackSlotKind::kStoreOwnNamed:
return "StoreOwnNamed";
case FeedbackSlotKind::kStoreGlobalSloppy:
return "StoreGlobalSloppy";
case FeedbackSlotKind::kStoreGlobalStrict:
return "StoreGlobalStrict";
case FeedbackSlotKind::kStoreKeyedSloppy:
return "StoreKeyedSloppy";
case FeedbackSlotKind::kStoreKeyedStrict:
return "StoreKeyedStrict";
case FeedbackSlotKind::kStoreInArrayLiteral:
return "StoreInArrayLiteral";
case FeedbackSlotKind::kBinaryOp:
return "BinaryOp";
case FeedbackSlotKind::kCompareOp:
return "CompareOp";
case FeedbackSlotKind::kStoreDataPropertyInLiteral:
return "StoreDataPropertyInLiteral";
case FeedbackSlotKind::kCreateClosure:
return "kCreateClosure";
case FeedbackSlotKind::kLiteral:
return "Literal";
case FeedbackSlotKind::kTypeProfile:
return "TypeProfile";
case FeedbackSlotKind::kForIn:
return "ForIn";
case FeedbackSlotKind::kInstanceOf:
return "InstanceOf";
case FeedbackSlotKind::kCloneObject:
return "CloneObject";
case FeedbackSlotKind::kKindsNumber:
break;
}
UNREACHABLE();
}
bool FeedbackMetadata::HasTypeProfileSlot() const {
FeedbackSlot slot =
FeedbackVector::ToSlot(FeedbackVectorSpec::kTypeProfileSlotIndex);
return slot.ToInt() < slot_count() &&
GetKind(slot) == FeedbackSlotKind::kTypeProfile;
}
FeedbackSlotKind FeedbackVector::GetKind(FeedbackSlot slot) const {
DCHECK(!is_empty());
return metadata()->GetKind(slot);
}
FeedbackSlot FeedbackVector::GetTypeProfileSlot() const {
DCHECK(metadata()->HasTypeProfileSlot());
FeedbackSlot slot =
FeedbackVector::ToSlot(FeedbackVectorSpec::kTypeProfileSlotIndex);
DCHECK_EQ(FeedbackSlotKind::kTypeProfile, GetKind(slot));
return slot;
}
// static
Handle<FeedbackVector> FeedbackVector::New(Isolate* isolate,
Handle<SharedFunctionInfo> shared) {
Factory* factory = isolate->factory();
const int slot_count = shared->feedback_metadata()->slot_count();
Handle<FeedbackVector> vector = factory->NewFeedbackVector(shared, TENURED);
DCHECK_EQ(vector->length(), slot_count);
DCHECK_EQ(vector->shared_function_info(), *shared);
DCHECK_EQ(
vector->optimized_code_weak_or_smi(),
MaybeObject::FromSmi(Smi::FromEnum(
FLAG_log_function_events ? OptimizationMarker::kLogFirstExecution
: OptimizationMarker::kNone)));
DCHECK_EQ(vector->invocation_count(), 0);
DCHECK_EQ(vector->profiler_ticks(), 0);
DCHECK_EQ(vector->deopt_count(), 0);
// Ensure we can skip the write barrier
Handle<Object> uninitialized_sentinel = UninitializedSentinel(isolate);
DCHECK_EQ(ReadOnlyRoots(isolate).uninitialized_symbol(),
*uninitialized_sentinel);
Handle<Oddball> undefined_value = factory->undefined_value();
for (int i = 0; i < slot_count;) {
FeedbackSlot slot(i);
FeedbackSlotKind kind = shared->feedback_metadata()->GetKind(slot);
int index = FeedbackVector::GetIndex(slot);
int entry_size = FeedbackMetadata::GetSlotSize(kind);
Object* extra_value = *uninitialized_sentinel;
switch (kind) {
case FeedbackSlotKind::kLoadGlobalInsideTypeof:
case FeedbackSlotKind::kLoadGlobalNotInsideTypeof:
case FeedbackSlotKind::kStoreGlobalSloppy:
case FeedbackSlotKind::kStoreGlobalStrict:
vector->set(index, HeapObjectReference::ClearedValue(),
SKIP_WRITE_BARRIER);
break;
case FeedbackSlotKind::kForIn:
case FeedbackSlotKind::kCompareOp:
case FeedbackSlotKind::kBinaryOp:
vector->set(index, Smi::kZero, SKIP_WRITE_BARRIER);
break;
case FeedbackSlotKind::kCreateClosure: {
Handle<FeedbackCell> cell = factory->NewNoClosuresCell(undefined_value);
vector->set(index, *cell);
break;
}
case FeedbackSlotKind::kLiteral:
vector->set(index, Smi::kZero, SKIP_WRITE_BARRIER);
break;
case FeedbackSlotKind::kCall:
vector->set(index, *uninitialized_sentinel, SKIP_WRITE_BARRIER);
extra_value = Smi::kZero;
break;
case FeedbackSlotKind::kCloneObject:
case FeedbackSlotKind::kLoadProperty:
case FeedbackSlotKind::kLoadKeyed:
case FeedbackSlotKind::kStoreNamedSloppy:
case FeedbackSlotKind::kStoreNamedStrict:
case FeedbackSlotKind::kStoreOwnNamed:
case FeedbackSlotKind::kStoreKeyedSloppy:
case FeedbackSlotKind::kStoreKeyedStrict:
case FeedbackSlotKind::kStoreInArrayLiteral:
case FeedbackSlotKind::kStoreDataPropertyInLiteral:
case FeedbackSlotKind::kTypeProfile:
case FeedbackSlotKind::kInstanceOf:
vector->set(index, *uninitialized_sentinel, SKIP_WRITE_BARRIER);
break;
case FeedbackSlotKind::kInvalid:
case FeedbackSlotKind::kKindsNumber:
UNREACHABLE();
break;
}
for (int j = 1; j < entry_size; j++) {
vector->set(index + j, extra_value, SKIP_WRITE_BARRIER);
}
i += entry_size;
}
Handle<FeedbackVector> result = Handle<FeedbackVector>::cast(vector);
if (!isolate->is_best_effort_code_coverage() ||
isolate->is_collecting_type_profile()) {
AddToVectorsForProfilingTools(isolate, result);
}
return result;
}
// static
void FeedbackVector::AddToVectorsForProfilingTools(
Isolate* isolate, Handle<FeedbackVector> vector) {
DCHECK(!isolate->is_best_effort_code_coverage() ||
isolate->is_collecting_type_profile());
if (!vector->shared_function_info()->IsSubjectToDebugging()) return;
Handle<ArrayList> list = Handle<ArrayList>::cast(
isolate->factory()->feedback_vectors_for_profiling_tools());
list = ArrayList::Add(isolate, list, vector);
isolate->SetFeedbackVectorsForProfilingTools(*list);
}
// static
void FeedbackVector::SetOptimizedCode(Handle<FeedbackVector> vector,
Handle<Code> code) {
DCHECK_EQ(code->kind(), Code::OPTIMIZED_FUNCTION);
vector->set_optimized_code_weak_or_smi(HeapObjectReference::Weak(*code));
}
void FeedbackVector::ClearOptimizedCode() {
DCHECK(has_optimized_code());
SetOptimizationMarker(OptimizationMarker::kNone);
}
void FeedbackVector::ClearOptimizationMarker() {
DCHECK(!has_optimized_code());
SetOptimizationMarker(OptimizationMarker::kNone);
}
void FeedbackVector::SetOptimizationMarker(OptimizationMarker marker) {
set_optimized_code_weak_or_smi(MaybeObject::FromSmi(Smi::FromEnum(marker)));
}
void FeedbackVector::EvictOptimizedCodeMarkedForDeoptimization(
SharedFunctionInfo* shared, const char* reason) {
MaybeObject* slot = optimized_code_weak_or_smi();
if (slot->IsSmi()) {
return;
}
if (slot->IsClearedWeakHeapObject()) {
ClearOptimizationMarker();
return;
}
Code* code = Code::cast(slot->GetHeapObject());
if (code->marked_for_deoptimization()) {
if (FLAG_trace_deopt) {
PrintF("[evicting optimizing code marked for deoptimization (%s) for ",
reason);
shared->ShortPrint();
PrintF("]\n");
}
if (!code->deopt_already_counted()) {
increment_deopt_count();
code->set_deopt_already_counted(true);
}
ClearOptimizedCode();
}
}
bool FeedbackVector::ClearSlots(Isolate* isolate) {
MaybeObject* uninitialized_sentinel = MaybeObject::FromObject(
FeedbackVector::RawUninitializedSentinel(isolate));
bool feedback_updated = false;
FeedbackMetadataIterator iter(metadata());
while (iter.HasNext()) {
FeedbackSlot slot = iter.Next();
MaybeObject* obj = Get(slot);
if (obj != uninitialized_sentinel) {
FeedbackNexus nexus(this, slot);
feedback_updated |= nexus.Clear();
}
}
return feedback_updated;
}
void FeedbackVector::AssertNoLegacyTypes(MaybeObject* object) {
#ifdef DEBUG
HeapObject* heap_object;
if (object->ToStrongOrWeakHeapObject(&heap_object)) {
// Instead of FixedArray, the Feedback and the Extra should contain
// WeakFixedArrays. The only allowed FixedArray subtype is HashTable.
DCHECK_IMPLIES(heap_object->IsFixedArray(), heap_object->IsHashTable());
DCHECK(!heap_object->IsWeakCell());
}
#endif
}
Handle<WeakFixedArray> FeedbackNexus::EnsureArrayOfSize(int length) {
Isolate* isolate = GetIsolate();
HeapObject* heap_object;
if (GetFeedback()->ToStrongHeapObject(&heap_object) &&
heap_object->IsWeakFixedArray() &&
WeakFixedArray::cast(heap_object)->length() == length) {
return handle(WeakFixedArray::cast(heap_object), isolate);
}
Handle<WeakFixedArray> array = isolate->factory()->NewWeakFixedArray(length);
SetFeedback(*array);
return array;
}
Handle<WeakFixedArray> FeedbackNexus::EnsureExtraArrayOfSize(int length) {
Isolate* isolate = GetIsolate();
HeapObject* heap_object;
if (GetFeedbackExtra()->ToStrongHeapObject(&heap_object) &&
heap_object->IsWeakFixedArray() &&
WeakFixedArray::cast(heap_object)->length() == length) {
return handle(WeakFixedArray::cast(heap_object), isolate);
}
Handle<WeakFixedArray> array = isolate->factory()->NewWeakFixedArray(length);
SetFeedbackExtra(*array);
return array;
}
void FeedbackNexus::ConfigureUninitialized() {
Isolate* isolate = GetIsolate();
switch (kind()) {
case FeedbackSlotKind::kStoreGlobalSloppy:
case FeedbackSlotKind::kStoreGlobalStrict:
case FeedbackSlotKind::kLoadGlobalNotInsideTypeof:
case FeedbackSlotKind::kLoadGlobalInsideTypeof: {
SetFeedback(HeapObjectReference::ClearedValue(), SKIP_WRITE_BARRIER);
SetFeedbackExtra(*FeedbackVector::UninitializedSentinel(isolate),
SKIP_WRITE_BARRIER);
break;
}
case FeedbackSlotKind::kCloneObject:
case FeedbackSlotKind::kCall: {
SetFeedback(*FeedbackVector::UninitializedSentinel(isolate),
SKIP_WRITE_BARRIER);
SetFeedbackExtra(Smi::kZero, SKIP_WRITE_BARRIER);
break;
}
case FeedbackSlotKind::kInstanceOf: {
SetFeedback(*FeedbackVector::UninitializedSentinel(isolate),
SKIP_WRITE_BARRIER);
break;
}
case FeedbackSlotKind::kStoreDataPropertyInLiteral: {
SetFeedback(*FeedbackVector::UninitializedSentinel(isolate),
SKIP_WRITE_BARRIER);
SetFeedbackExtra(*FeedbackVector::UninitializedSentinel(isolate),
SKIP_WRITE_BARRIER);
break;
}
default:
UNREACHABLE();
}
}
bool FeedbackNexus::Clear() {
bool feedback_updated = false;
switch (kind()) {
case FeedbackSlotKind::kCreateClosure:
case FeedbackSlotKind::kTypeProfile:
// We don't clear these kinds ever.
break;
case FeedbackSlotKind::kCompareOp:
case FeedbackSlotKind::kForIn:
case FeedbackSlotKind::kBinaryOp:
// We don't clear these, either.
break;
case FeedbackSlotKind::kLiteral:
SetFeedback(Smi::kZero, SKIP_WRITE_BARRIER);
feedback_updated = true;
break;
case FeedbackSlotKind::kStoreNamedSloppy:
case FeedbackSlotKind::kStoreNamedStrict:
case FeedbackSlotKind::kStoreKeyedSloppy:
case FeedbackSlotKind::kStoreKeyedStrict:
case FeedbackSlotKind::kStoreInArrayLiteral:
case FeedbackSlotKind::kStoreOwnNamed:
case FeedbackSlotKind::kLoadProperty:
case FeedbackSlotKind::kLoadKeyed:
if (!IsCleared()) {
ConfigurePremonomorphic();
feedback_updated = true;
}
break;
case FeedbackSlotKind::kStoreGlobalSloppy:
case FeedbackSlotKind::kStoreGlobalStrict:
case FeedbackSlotKind::kLoadGlobalNotInsideTypeof:
case FeedbackSlotKind::kLoadGlobalInsideTypeof:
case FeedbackSlotKind::kCall:
case FeedbackSlotKind::kInstanceOf:
case FeedbackSlotKind::kStoreDataPropertyInLiteral:
case FeedbackSlotKind::kCloneObject:
if (!IsCleared()) {
ConfigureUninitialized();
feedback_updated = true;
}
break;
case FeedbackSlotKind::kInvalid:
case FeedbackSlotKind::kKindsNumber:
UNREACHABLE();
break;
}
return feedback_updated;
}
void FeedbackNexus::ConfigurePremonomorphic() {
SetFeedback(*FeedbackVector::PremonomorphicSentinel(GetIsolate()),
SKIP_WRITE_BARRIER);
SetFeedbackExtra(*FeedbackVector::UninitializedSentinel(GetIsolate()),
SKIP_WRITE_BARRIER);
}
bool FeedbackNexus::ConfigureMegamorphic() {
DisallowHeapAllocation no_gc;
Isolate* isolate = GetIsolate();
MaybeObject* sentinel =
MaybeObject::FromObject(*FeedbackVector::MegamorphicSentinel(isolate));
if (GetFeedback() != sentinel) {
SetFeedback(sentinel, SKIP_WRITE_BARRIER);
SetFeedbackExtra(HeapObjectReference::ClearedValue());
return true;
}
return false;
}
bool FeedbackNexus::ConfigureMegamorphic(IcCheckType property_type) {
DisallowHeapAllocation no_gc;
Isolate* isolate = GetIsolate();
bool changed = false;
MaybeObject* sentinel =
MaybeObject::FromObject(*FeedbackVector::MegamorphicSentinel(isolate));
if (GetFeedback() != sentinel) {
SetFeedback(sentinel, SKIP_WRITE_BARRIER);
changed = true;
}
Smi* extra = Smi::FromInt(static_cast<int>(property_type));
if (changed || GetFeedbackExtra() != MaybeObject::FromSmi(extra)) {
SetFeedbackExtra(extra, SKIP_WRITE_BARRIER);
changed = true;
}
return changed;
}
InlineCacheState FeedbackNexus::StateFromFeedback() const {
Isolate* isolate = GetIsolate();
MaybeObject* feedback = GetFeedback();
switch (kind()) {
case FeedbackSlotKind::kCreateClosure:
case FeedbackSlotKind::kLiteral:
// CreateClosure and literal slots don't have a notion of state.
UNREACHABLE();
break;
case FeedbackSlotKind::kStoreGlobalSloppy:
case FeedbackSlotKind::kStoreGlobalStrict:
case FeedbackSlotKind::kLoadGlobalNotInsideTypeof:
case FeedbackSlotKind::kLoadGlobalInsideTypeof: {
if (feedback->IsSmi()) return MONOMORPHIC;
DCHECK(feedback->IsWeakOrClearedHeapObject());
MaybeObject* extra = GetFeedbackExtra();
if (!feedback->IsClearedWeakHeapObject() ||
extra != MaybeObject::FromObject(
*FeedbackVector::UninitializedSentinel(isolate))) {
return MONOMORPHIC;
}
return UNINITIALIZED;
}
case FeedbackSlotKind::kStoreNamedSloppy:
case FeedbackSlotKind::kStoreNamedStrict:
case FeedbackSlotKind::kStoreKeyedSloppy:
case FeedbackSlotKind::kStoreKeyedStrict:
case FeedbackSlotKind::kStoreInArrayLiteral:
case FeedbackSlotKind::kStoreOwnNamed:
case FeedbackSlotKind::kLoadProperty:
case FeedbackSlotKind::kLoadKeyed: {
if (feedback == MaybeObject::FromObject(
*FeedbackVector::UninitializedSentinel(isolate))) {
return UNINITIALIZED;
}
if (feedback == MaybeObject::FromObject(
*FeedbackVector::MegamorphicSentinel(isolate))) {
return MEGAMORPHIC;
}
if (feedback == MaybeObject::FromObject(
*FeedbackVector::PremonomorphicSentinel(isolate))) {
return PREMONOMORPHIC;
}
if (feedback->IsWeakOrClearedHeapObject()) {
// Don't check if the map is cleared.
return MONOMORPHIC;
}
HeapObject* heap_object;
if (feedback->ToStrongHeapObject(&heap_object)) {
if (heap_object->IsWeakFixedArray()) {
// Determine state purely by our structure, don't check if the maps
// are cleared.
return POLYMORPHIC;
}
if (heap_object->IsName()) {
DCHECK(IsKeyedLoadICKind(kind()) || IsKeyedStoreICKind(kind()));
Object* extra = GetFeedbackExtra()->ToStrongHeapObject();
WeakFixedArray* extra_array = WeakFixedArray::cast(extra);
return extra_array->length() > 2 ? POLYMORPHIC : MONOMORPHIC;
}
}
UNREACHABLE();
}
case FeedbackSlotKind::kCall: {
HeapObject* heap_object;
if (feedback == MaybeObject::FromObject(
*FeedbackVector::MegamorphicSentinel(isolate))) {
return GENERIC;
} else if (feedback->IsWeakOrClearedHeapObject() ||
(feedback->ToStrongHeapObject(&heap_object) &&
heap_object->IsAllocationSite())) {
return MONOMORPHIC;
}
CHECK_EQ(feedback, MaybeObject::FromObject(
*FeedbackVector::UninitializedSentinel(isolate)));
return UNINITIALIZED;
}
case FeedbackSlotKind::kBinaryOp: {
BinaryOperationHint hint = GetBinaryOperationFeedback();
if (hint == BinaryOperationHint::kNone) {
return UNINITIALIZED;
} else if (hint == BinaryOperationHint::kAny) {
return GENERIC;
}
return MONOMORPHIC;
}
case FeedbackSlotKind::kCompareOp: {
CompareOperationHint hint = GetCompareOperationFeedback();
if (hint == CompareOperationHint::kNone) {
return UNINITIALIZED;
} else if (hint == CompareOperationHint::kAny) {
return GENERIC;
}
return MONOMORPHIC;
}
case FeedbackSlotKind::kForIn: {
ForInHint hint = GetForInFeedback();
if (hint == ForInHint::kNone) {
return UNINITIALIZED;
} else if (hint == ForInHint::kAny) {
return GENERIC;
}
return MONOMORPHIC;
}
case FeedbackSlotKind::kInstanceOf: {
if (feedback == MaybeObject::FromObject(
*FeedbackVector::UninitializedSentinel(isolate))) {
return UNINITIALIZED;
} else if (feedback ==
MaybeObject::FromObject(
*FeedbackVector::MegamorphicSentinel(isolate))) {
return MEGAMORPHIC;
}
return MONOMORPHIC;
}
case FeedbackSlotKind::kStoreDataPropertyInLiteral: {
if (feedback == MaybeObject::FromObject(
*FeedbackVector::UninitializedSentinel(isolate))) {
return UNINITIALIZED;
} else if (feedback->IsWeakOrClearedHeapObject()) {
// Don't check if the map is cleared.
return MONOMORPHIC;
}
return MEGAMORPHIC;
}
case FeedbackSlotKind::kTypeProfile: {
if (feedback == MaybeObject::FromObject(
*FeedbackVector::UninitializedSentinel(isolate))) {
return UNINITIALIZED;
}
return MONOMORPHIC;
}
case FeedbackSlotKind::kCloneObject: {
if (feedback == MaybeObject::FromObject(
*FeedbackVector::UninitializedSentinel(isolate))) {
return UNINITIALIZED;
}
if (feedback == MaybeObject::FromObject(
*FeedbackVector::MegamorphicSentinel(isolate))) {
return MEGAMORPHIC;
}
if (feedback->IsWeakOrClearedHeapObject()) {
return MONOMORPHIC;
}
DCHECK(feedback->ToStrongHeapObject()->IsWeakFixedArray());
return POLYMORPHIC;
}
case FeedbackSlotKind::kInvalid:
case FeedbackSlotKind::kKindsNumber:
UNREACHABLE();
break;
}
return UNINITIALIZED;
}
void FeedbackNexus::ConfigurePropertyCellMode(Handle<PropertyCell> cell) {
DCHECK(IsGlobalICKind(kind()));
Isolate* isolate = GetIsolate();
SetFeedback(HeapObjectReference::Weak(*cell));
SetFeedbackExtra(*FeedbackVector::UninitializedSentinel(isolate),
SKIP_WRITE_BARRIER);
}
bool FeedbackNexus::ConfigureLexicalVarMode(int script_context_index,
int context_slot_index) {
DCHECK(IsGlobalICKind(kind()));
DCHECK_LE(0, script_context_index);
DCHECK_LE(0, context_slot_index);
if (!ContextIndexBits::is_valid(script_context_index) ||
!SlotIndexBits::is_valid(context_slot_index)) {
return false;
}
int config = ContextIndexBits::encode(script_context_index) |
SlotIndexBits::encode(context_slot_index);
SetFeedback(Smi::FromInt(config));
Isolate* isolate = GetIsolate();
SetFeedbackExtra(*FeedbackVector::UninitializedSentinel(isolate),
SKIP_WRITE_BARRIER);
return true;
}
void FeedbackNexus::ConfigureHandlerMode(const MaybeObjectHandle& handler) {
DCHECK(IsGlobalICKind(kind()));
DCHECK(IC::IsHandler(*handler));
SetFeedback(HeapObjectReference::ClearedValue());
SetFeedbackExtra(*handler);
}
void FeedbackNexus::ConfigureCloneObject(Handle<Map> source_map,
Handle<Map> result_map) {
Isolate* isolate = GetIsolate();
MaybeObject* maybe_feedback = GetFeedback();
Handle<HeapObject> feedback(maybe_feedback->IsStrongOrWeakHeapObject()
? maybe_feedback->GetHeapObject()
: nullptr,
isolate);
switch (ic_state()) {
case UNINITIALIZED:
// Cache the first map seen which meets the fast case requirements.
SetFeedback(HeapObjectReference::Weak(*source_map));
SetFeedbackExtra(*result_map);
break;
case MONOMORPHIC:
if (maybe_feedback->IsClearedWeakHeapObject()) {
// Remain in MONOMORPHIC state if previous feedback has been collected.
SetFeedback(HeapObjectReference::Weak(*source_map));
SetFeedbackExtra(*result_map);
} else {
// Transition to POLYMORPHIC.
DCHECK_NE(*source_map, *feedback);
Handle<WeakFixedArray> array =
EnsureArrayOfSize(2 * kCloneObjectPolymorphicEntrySize);
array->Set(0, maybe_feedback);
array->Set(1, GetFeedbackExtra());
array->Set(2, HeapObjectReference::Weak(*source_map));
array->Set(3, MaybeObject::FromObject(*result_map));
SetFeedbackExtra(HeapObjectReference::ClearedValue());
}
break;
case POLYMORPHIC: {
static constexpr int kMaxElements =
IC::kMaxPolymorphicMapCount * kCloneObjectPolymorphicEntrySize;
Handle<WeakFixedArray> array = Handle<WeakFixedArray>::cast(feedback);
int i = 0;
for (; i < array->length(); i += kCloneObjectPolymorphicEntrySize) {
if (array->Get(i)->IsClearedWeakHeapObject()) {
break;
}
DCHECK_NE(array->Get(i)->GetHeapObject(), *source_map);
}
if (i >= array->length()) {
if (i == kMaxElements) {
// Transition to MEGAMORPHIC.
MaybeObject* sentinel = MaybeObject::FromObject(
*FeedbackVector::MegamorphicSentinel(isolate));
SetFeedback(sentinel, SKIP_WRITE_BARRIER);
SetFeedbackExtra(HeapObjectReference::ClearedValue());
break;
}
// Grow polymorphic feedback array.
Handle<WeakFixedArray> new_array = EnsureArrayOfSize(
array->length() + kCloneObjectPolymorphicEntrySize);
for (int j = 0; j < array->length(); ++j) {
new_array->Set(j, array->Get(j));
}
array = new_array;
}
array->Set(i, HeapObjectReference::Weak(*source_map));
array->Set(i + 1, MaybeObject::FromObject(*result_map));
break;
}
default:
UNREACHABLE();
}
}
int FeedbackNexus::GetCallCount() {
DCHECK(IsCallICKind(kind()));
Object* call_count = GetFeedbackExtra()->ToObject();
CHECK(call_count->IsSmi());
uint32_t value = static_cast<uint32_t>(Smi::ToInt(call_count));
return CallCountField::decode(value);
}
void FeedbackNexus::SetSpeculationMode(SpeculationMode mode) {
DCHECK(IsCallICKind(kind()));
Object* call_count = GetFeedbackExtra()->ToObject();
CHECK(call_count->IsSmi());
uint32_t count = static_cast<uint32_t>(Smi::ToInt(call_count));
uint32_t value = CallCountField::encode(CallCountField::decode(count));
int result = static_cast<int>(value | SpeculationModeField::encode(mode));
SetFeedbackExtra(Smi::FromInt(result), SKIP_WRITE_BARRIER);
}
SpeculationMode FeedbackNexus::GetSpeculationMode() {
DCHECK(IsCallICKind(kind()));
Object* call_count = GetFeedbackExtra()->ToObject();
CHECK(call_count->IsSmi());
uint32_t value = static_cast<uint32_t>(Smi::ToInt(call_count));
return SpeculationModeField::decode(value);
}
float FeedbackNexus::ComputeCallFrequency() {
DCHECK(IsCallICKind(kind()));
double const invocation_count = vector()->invocation_count();
double const call_count = GetCallCount();
if (invocation_count == 0) {
// Prevent division by 0.
return 0.0f;
}
return static_cast<float>(call_count / invocation_count);
}
void FeedbackNexus::ConfigureMonomorphic(Handle<Name> name,
Handle<Map> receiver_map,
const MaybeObjectHandle& handler) {
DCHECK(handler.is_null() || IC::IsHandler(*handler));
if (kind() == FeedbackSlotKind::kStoreDataPropertyInLiteral) {
SetFeedback(HeapObjectReference::Weak(*receiver_map));
SetFeedbackExtra(*name);
} else {
if (name.is_null()) {
SetFeedback(HeapObjectReference::Weak(*receiver_map));
SetFeedbackExtra(*handler);
} else {
Handle<WeakFixedArray> array = EnsureExtraArrayOfSize(2);
SetFeedback(*name);
array->Set(0, HeapObjectReference::Weak(*receiver_map));
array->Set(1, *handler);
}
}
}
void FeedbackNexus::ConfigurePolymorphic(Handle<Name> name,
MapHandles const& maps,
MaybeObjectHandles* handlers) {
DCHECK_EQ(handlers->size(), maps.size());
int receiver_count = static_cast<int>(maps.size());
DCHECK_GT(receiver_count, 1);
Handle<WeakFixedArray> array;
if (name.is_null()) {
array = EnsureArrayOfSize(receiver_count * 2);
SetFeedbackExtra(*FeedbackVector::UninitializedSentinel(GetIsolate()),
SKIP_WRITE_BARRIER);
} else {
array = EnsureExtraArrayOfSize(receiver_count * 2);
SetFeedback(*name);
}
for (int current = 0; current < receiver_count; ++current) {
Handle<Map> map = maps[current];
array->Set(current * 2, HeapObjectReference::Weak(*map));
DCHECK(IC::IsHandler(*handlers->at(current)));
array->Set(current * 2 + 1, *handlers->at(current));
}
}
int FeedbackNexus::ExtractMaps(MapHandles* maps) const {
DCHECK(IsLoadICKind(kind()) || IsStoreICKind(kind()) ||
IsKeyedLoadICKind(kind()) || IsKeyedStoreICKind(kind()) ||
IsStoreOwnICKind(kind()) || IsStoreDataPropertyInLiteralKind(kind()) ||
IsStoreInArrayLiteralICKind(kind()));
Isolate* isolate = GetIsolate();
MaybeObject* feedback = GetFeedback();
bool is_named_feedback = IsPropertyNameFeedback(feedback);
HeapObject* heap_object;
if ((feedback->ToStrongHeapObject(&heap_object) &&
heap_object->IsWeakFixedArray()) ||
is_named_feedback) {
int found = 0;
WeakFixedArray* array;
if (is_named_feedback) {
array = WeakFixedArray::cast(GetFeedbackExtra()->ToStrongHeapObject());
} else {
array = WeakFixedArray::cast(heap_object);
}
const int increment = 2;
HeapObject* heap_object;
for (int i = 0; i < array->length(); i += increment) {
DCHECK(array->Get(i)->IsWeakOrClearedHeapObject());
if (array->Get(i)->ToWeakHeapObject(&heap_object)) {
Map* map = Map::cast(heap_object);
maps->push_back(handle(map, isolate));
found++;
}
}
return found;
} else if (feedback->ToWeakHeapObject(&heap_object)) {
Map* map = Map::cast(heap_object);
maps->push_back(handle(map, isolate));
return 1;
}
return 0;
}
MaybeObjectHandle FeedbackNexus::FindHandlerForMap(Handle<Map> map) const {
DCHECK(IsLoadICKind(kind()) || IsStoreICKind(kind()) ||
IsKeyedLoadICKind(kind()) || IsKeyedStoreICKind(kind()) ||
IsStoreOwnICKind(kind()) || IsStoreDataPropertyInLiteralKind(kind()));
MaybeObject* feedback = GetFeedback();
Isolate* isolate = GetIsolate();
bool is_named_feedback = IsPropertyNameFeedback(feedback);
HeapObject* heap_object;
if ((feedback->ToStrongHeapObject(&heap_object) &&
heap_object->IsWeakFixedArray()) ||
is_named_feedback) {
WeakFixedArray* array;
if (is_named_feedback) {
array = WeakFixedArray::cast(GetFeedbackExtra()->ToStrongHeapObject());
} else {
array = WeakFixedArray::cast(heap_object);
}
const int increment = 2;
HeapObject* heap_object;
for (int i = 0; i < array->length(); i += increment) {
DCHECK(array->Get(i)->IsWeakOrClearedHeapObject());
if (array->Get(i)->ToWeakHeapObject(&heap_object)) {
Map* array_map = Map::cast(heap_object);
if (array_map == *map &&
!array->Get(i + increment - 1)->IsClearedWeakHeapObject()) {
MaybeObject* handler = array->Get(i + increment - 1);
DCHECK(IC::IsHandler(handler));
return handle(handler, isolate);
}
}
}
} else if (feedback->ToWeakHeapObject(&heap_object)) {
Map* cell_map = Map::cast(heap_object);
if (cell_map == *map && !GetFeedbackExtra()->IsClearedWeakHeapObject()) {
MaybeObject* handler = GetFeedbackExtra();
DCHECK(IC::IsHandler(handler));
return handle(handler, isolate);
}
}
return MaybeObjectHandle();
}
bool FeedbackNexus::FindHandlers(MaybeObjectHandles* code_list,
int length) const {
DCHECK(IsLoadICKind(kind()) || IsStoreICKind(kind()) ||
IsKeyedLoadICKind(kind()) || IsKeyedStoreICKind(kind()) ||
IsStoreOwnICKind(kind()) || IsStoreDataPropertyInLiteralKind(kind()) ||
IsStoreInArrayLiteralICKind(kind()));
MaybeObject* feedback = GetFeedback();
Isolate* isolate = GetIsolate();
int count = 0;
bool is_named_feedback = IsPropertyNameFeedback(feedback);
HeapObject* heap_object;
if ((feedback->ToStrongHeapObject(&heap_object) &&
heap_object->IsWeakFixedArray()) ||
is_named_feedback) {
WeakFixedArray* array;
if (is_named_feedback) {
array = WeakFixedArray::cast(GetFeedbackExtra()->ToStrongHeapObject());