templates-inl.h

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// Copyright 2018 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.
 
#ifndef V8_OBJECTS_TEMPLATES_INL_H_
#define V8_OBJECTS_TEMPLATES_INL_H_
 
#include "src/objects/templates.h"
// Include the non-inl header before the rest of the headers.
 
#include "src/heap/heap-write-barrier-inl.h"
#include "src/objects/dictionary.h"
#include "src/objects/objects-inl.h"
#include "src/objects/oddball.h"
#include "src/objects/shared-function-info.h"
 
// Has to be the last include (doesn't have include guards):
#include "src/objects/object-macros.h"
 
namespace v8 {
namespace internal {
 
#include "torque-generated/src/objects/templates-tq-inl.inc"
 
TQ_OBJECT_CONSTRUCTORS_IMPL(TemplateInfo)
TQ_OBJECT_CONSTRUCTORS_IMPL(TemplateInfoWithProperties)
TQ_OBJECT_CONSTRUCTORS_IMPL(FunctionTemplateInfo)
TQ_OBJECT_CONSTRUCTORS_IMPL(ObjectTemplateInfo)
TQ_OBJECT_CONSTRUCTORS_IMPL(FunctionTemplateRareData)
TQ_OBJECT_CONSTRUCTORS_IMPL(DictionaryTemplateInfo)
 
NEVER_READ_ONLY_SPACE_IMPL(DictionaryTemplateInfo)
NEVER_READ_ONLY_SPACE_IMPL(ObjectTemplateInfo)
 
BOOL_ACCESSORS(FunctionTemplateInfo, relaxed_flag,
               is_object_template_call_handler,
               IsObjectTemplateCallHandlerBit::kShift)
BOOL_ACCESSORS(FunctionTemplateInfo, relaxed_flag, has_side_effects,
               HasSideEffectsBit::kShift)
BOOL_ACCESSORS(FunctionTemplateInfo, relaxed_flag, undetectable,
               UndetectableBit::kShift)
BOOL_ACCESSORS(FunctionTemplateInfo, relaxed_flag, needs_access_check,
               NeedsAccessCheckBit::kShift)
BOOL_ACCESSORS(FunctionTemplateInfo, relaxed_flag, read_only_prototype,
               ReadOnlyPrototypeBit::kShift)
BOOL_ACCESSORS(FunctionTemplateInfo, relaxed_flag, remove_prototype,
               RemovePrototypeBit::kShift)
BOOL_ACCESSORS(FunctionTemplateInfo, relaxed_flag, accept_any_receiver,
               AcceptAnyReceiverBit::kShift)
 
bool FunctionTemplateInfo::published() const {
  return BooleanBit::get(relaxed_flag(), PublishedBit::kShift);
}
 
void FunctionTemplateInfo::set_published(bool value) {
  DCHECK(value);
  if (published()) return;
  CHECK(!HeapLayout::InReadOnlySpace(*this));
  set_relaxed_flag(
      BooleanBit::set(relaxed_flag(), PublishedBit::kShift, value));
}
 
BIT_FIELD_ACCESSORS(
    FunctionTemplateInfo, relaxed_flag,
    allowed_receiver_instance_type_range_start,
    FunctionTemplateInfo::AllowedReceiverInstanceTypeRangeStartBits)
BIT_FIELD_ACCESSORS(
    FunctionTemplateInfo, relaxed_flag,
    allowed_receiver_instance_type_range_end,
    FunctionTemplateInfo::AllowedReceiverInstanceTypeRangeEndBits)
 
RELAXED_UINT32_ACCESSORS(FunctionTemplateInfo, flag,
                         FunctionTemplateInfo::kFlagOffset)
 
int32_t FunctionTemplateInfo::relaxed_flag() const {
  return flag(kRelaxedLoad);
}
void FunctionTemplateInfo::set_relaxed_flag(int32_t flags) {
  return set_flag(flags, kRelaxedStore);
}
 
Address FunctionTemplateInfo::callback(i::IsolateForSandbox isolate) const {
  Address result = maybe_redirected_callback(isolate);
  if (!USE_SIMULATOR_BOOL) return result;
  if (result == kNullAddress) return kNullAddress;
  return ExternalReference::UnwrapRedirection(result);
}
 
void FunctionTemplateInfo::init_callback(i::IsolateForSandbox isolate,
                                         Address initial_value) {
  init_maybe_redirected_callback(isolate, initial_value);
  if (USE_SIMULATOR_BOOL) {
    init_callback_redirection(isolate);
  }
}
 
void FunctionTemplateInfo::set_callback(i::IsolateForSandbox isolate,
                                        Address value) {
  set_maybe_redirected_callback(isolate, value);
  if (USE_SIMULATOR_BOOL) {
    init_callback_redirection(isolate);
  }
}
 
void FunctionTemplateInfo::init_callback_redirection(
    i::IsolateForSandbox isolate) {
  CHECK(USE_SIMULATOR_BOOL);
  Address value = maybe_redirected_callback(isolate);
  if (value == kNullAddress) return;
  value =
      ExternalReference::Redirect(value, ExternalReference::DIRECT_API_CALL);
  set_maybe_redirected_callback(isolate, value);
}
 
void FunctionTemplateInfo::remove_callback_redirection(
    i::IsolateForSandbox isolate) {
  CHECK(USE_SIMULATOR_BOOL);
  Address value = callback(isolate);
  set_maybe_redirected_callback(isolate, value);
}
 
EXTERNAL_POINTER_ACCESSORS_MAYBE_READ_ONLY_HOST(
    FunctionTemplateInfo, maybe_redirected_callback, Address,
    kMaybeRedirectedCallbackOffset, kFunctionTemplateInfoCallbackTag)
 
template <class IsolateT>
bool FunctionTemplateInfo::has_callback(IsolateT* isolate) const {
  return !IsTheHole(callback_data(kAcquireLoad), isolate);
}
 
// static
Tagged<FunctionTemplateRareData>
FunctionTemplateInfo::EnsureFunctionTemplateRareData(
    Isolate* isolate,
    DirectHandle<FunctionTemplateInfo> function_template_info) {
  Tagged<HeapObject> extra =
      function_template_info->rare_data(isolate, kAcquireLoad);
  if (IsUndefined(extra, isolate)) {
    return AllocateFunctionTemplateRareData(isolate, function_template_info);
  } else {
    return Cast<FunctionTemplateRareData>(extra);
  }
}
 
#define RARE_ACCESSORS(Name, CamelName, Default, ...)                          \
  DEF_GETTER(FunctionTemplateInfo, Get##CamelName, Tagged<__VA_ARGS__>) {      \
    Tagged<HeapObject> extra = rare_data(cage_base, kAcquireLoad);             \
    Tagged<Undefined> undefined = GetReadOnlyRoots().undefined_value();        \
    return extra == undefined ? Default                                        \
                              : Cast<FunctionTemplateRareData>(extra)->Name(); \
  }                                                                            \
  inline void FunctionTemplateInfo::Set##CamelName(                            \
      Isolate* isolate,                                                        \
      DirectHandle<FunctionTemplateInfo> function_template_info,               \
      DirectHandle<__VA_ARGS__> Name) {                                        \
    Tagged<FunctionTemplateRareData> rare_data =                               \
        EnsureFunctionTemplateRareData(isolate, function_template_info);       \
    rare_data->set_##Name(*Name);                                              \
  }
 
RARE_ACCESSORS(prototype_template, PrototypeTemplate, undefined,
               UnionOf<Undefined, ObjectTemplateInfo>)
RARE_ACCESSORS(prototype_provider_template, PrototypeProviderTemplate,
               undefined, UnionOf<Undefined, FunctionTemplateInfo>)
RARE_ACCESSORS(parent_template, ParentTemplate, undefined,
               UnionOf<Undefined, FunctionTemplateInfo>)
RARE_ACCESSORS(named_property_handler, NamedPropertyHandler, undefined,
               UnionOf<Undefined, InterceptorInfo>)
RARE_ACCESSORS(indexed_property_handler, IndexedPropertyHandler, undefined,
               UnionOf<Undefined, InterceptorInfo>)
RARE_ACCESSORS(instance_template, InstanceTemplate, undefined,
               UnionOf<Undefined, ObjectTemplateInfo>)
RARE_ACCESSORS(instance_call_handler, InstanceCallHandler, undefined,
               UnionOf<Undefined, FunctionTemplateInfo>)
RARE_ACCESSORS(access_check_info, AccessCheckInfo, undefined,
               UnionOf<Undefined, AccessCheckInfo>)
RARE_ACCESSORS(c_function_overloads, CFunctionOverloads,
               GetReadOnlyRoots().empty_fixed_array(), FixedArray)
#undef RARE_ACCESSORS
 
InstanceType FunctionTemplateInfo::GetInstanceType() const {
  int type = instance_type();
  DCHECK(base::IsInRange(type, Internals::kFirstJSApiObjectType,
                         Internals::kLastJSApiObjectType));
  return static_cast<InstanceType>(type);
}
 
void FunctionTemplateInfo::SetInstanceType(int api_instance_type) {
  // Translate |api_instance_type| value from range
  // [Internals::kFirstEmbedderJSApiObjectType,
  //  Internals::kLastEmbedderJSApiObjectType] to range
  // [Internals::kFirstJSApiObjectType, Internals::kLastJSApiObjectType].
  DCHECK_LE(Internals::kFirstEmbedderJSApiObjectType, api_instance_type);
  DCHECK_LE(api_instance_type, Internals::kLastEmbedderJSApiObjectType);
  // kNoJSApiObjectType must correspond to JS_API_OBJECT_TYPE.
  static_assert(kNoJSApiObjectType == 0);
  static_assert(JS_API_OBJECT_TYPE == Internals::kFirstJSApiObjectType);
  set_instance_type(static_cast<InstanceType>(
      api_instance_type + Internals::kFirstJSApiObjectType));
}
 
void FunctionTemplateInfo::SetAllowedReceiverInstanceTypeRange(
    int api_instance_type_start, int api_instance_type_end) {
  // Translate |api_instance_type_start| and |api_instance_type_end| values
  // from range [Internals::kFirstEmbedderJSApiObjectType,
  //             Internals::kLastEmbedderJSApiObjectType] to range
  // [Internals::kFirstJSApiObjectType, Internals::kLastJSApiObjectType].
  DCHECK_LE(Internals::kFirstEmbedderJSApiObjectType, api_instance_type_start);
  DCHECK_LE(api_instance_type_start, api_instance_type_end);
  DCHECK_LE(api_instance_type_end, Internals::kLastEmbedderJSApiObjectType);
  // kNoJSApiObjectType must correspond to JS_API_OBJECT_TYPE.
  static_assert(kNoJSApiObjectType == 0);
  static_assert(JS_API_OBJECT_TYPE == Internals::kFirstJSApiObjectType);
  set_allowed_receiver_instance_type_range_start(static_cast<InstanceType>(
      api_instance_type_start + Internals::kFirstJSApiObjectType));
  set_allowed_receiver_instance_type_range_end(static_cast<InstanceType>(
      api_instance_type_end + Internals::kFirstJSApiObjectType));
}
 
// Ensure that instance type fields in FunctionTemplateInfo are big enough
// to fit the whole JSApiObject type range.
static_assert(
    FunctionTemplateInfo::AllowedReceiverInstanceTypeRangeStartBits::is_valid(
        LAST_JS_API_OBJECT_TYPE));
static_assert(
    FunctionTemplateInfo::AllowedReceiverInstanceTypeRangeEndBits::is_valid(
        LAST_JS_API_OBJECT_TYPE));
 
bool FunctionTemplateInfo::instantiated() {
  return IsSharedFunctionInfo(shared_function_info());
}
 
inline bool FunctionTemplateInfo::BreakAtEntry(Isolate* isolate) {
  Tagged<Object> maybe_shared = shared_function_info();
  if (IsSharedFunctionInfo(maybe_shared)) {
    Tagged<SharedFunctionInfo> shared = Cast<SharedFunctionInfo>(maybe_shared);
    return shared->BreakAtEntry(isolate);
  }
  return false;
}
 
Tagged<FunctionTemplateInfo> FunctionTemplateInfo::GetParent(Isolate* isolate) {
  Tagged<Object> parent = GetParentTemplate();
  return IsUndefined(parent, isolate) ? Tagged<FunctionTemplateInfo>{}
                                      : Cast<FunctionTemplateInfo>(parent);
}
 
Tagged<ObjectTemplateInfo> ObjectTemplateInfo::GetParent(Isolate* isolate) {
  Tagged<Object> maybe_ctor = constructor();
  if (IsUndefined(maybe_ctor, isolate)) return ObjectTemplateInfo();
  Tagged<FunctionTemplateInfo> constructor =
      Cast<FunctionTemplateInfo>(maybe_ctor);
  while (true) {
    constructor = constructor->GetParent(isolate);
    if (constructor.is_null()) return ObjectTemplateInfo();
    Tagged<Object> maybe_obj = constructor->GetInstanceTemplate();
    if (!IsUndefined(maybe_obj, isolate)) {
      return Cast<ObjectTemplateInfo>(maybe_obj);
    }
  }
  return Tagged<ObjectTemplateInfo>();
}
 
int ObjectTemplateInfo::embedder_field_count() const {
  return EmbedderFieldCountBits::decode(data());
}
 
void ObjectTemplateInfo::set_embedder_field_count(int count) {
  DCHECK_LE(count, JSObject::kMaxEmbedderFields);
  return set_data(EmbedderFieldCountBits::update(data(), count));
}
 
bool ObjectTemplateInfo::immutable_proto() const {
  return IsImmutablePrototypeBit::decode(data());
}
 
void ObjectTemplateInfo::set_immutable_proto(bool immutable) {
  return set_data(IsImmutablePrototypeBit::update(data(), immutable));
}
 
bool ObjectTemplateInfo::code_like() const {
  return IsCodeKindBit::decode(data());
}
 
void ObjectTemplateInfo::set_code_like(bool is_code_like) {
  return set_data(IsCodeKindBit::update(data(), is_code_like));
}
 
bool FunctionTemplateInfo::IsTemplateFor(Tagged<JSObject> object) const {
  return IsTemplateFor(object->map());
}
 
bool TemplateInfo::TryGetIsolate(Isolate** isolate) const {
  if (GetIsolateFromHeapObject(*this, isolate)) return true;
  Isolate* isolate_value = Isolate::TryGetCurrent();
  if (isolate_value != nullptr) {
    *isolate = isolate_value;
    return true;
  }
  return false;
}
 
Isolate* TemplateInfo::GetIsolateChecked() const {
  Isolate* isolate;
  CHECK(TryGetIsolate(&isolate));
  return isolate;
}
 
bool TemplateInfo::is_cacheable() const {
  return IsCacheableBit::decode(template_info_flags());
}
void TemplateInfo::set_is_cacheable(bool is_cacheable) {
  set_template_info_flags(
      IsCacheableBit::update(template_info_flags(), is_cacheable));
}
 
bool TemplateInfo::should_promote_to_read_only() const {
  return ShouldPromoteToReadOnlyBit::decode(template_info_flags());
}
void TemplateInfo::set_should_promote_to_read_only(
    bool should_promote_to_read_only) {
  DCHECK(should_promote_to_read_only);
  set_template_info_flags(ShouldPromoteToReadOnlyBit::update(
      template_info_flags(), should_promote_to_read_only));
}
 
uint32_t TemplateInfo::serial_number() const {
  return SerialNumberBits::decode(template_info_flags());
}
void TemplateInfo::set_serial_number(uint32_t value) {
  set_template_info_flags(
      SerialNumberBits::update(template_info_flags(), value));
}
 
uint32_t TemplateInfo::EnsureHasSerialNumber(Isolate* isolate) {
  uint32_t serial_number = this->serial_number();
  if (serial_number == kUninitializedSerialNumber) {
    CHECK(!HeapLayout::InReadOnlySpace(*this));
    serial_number = isolate->heap()->GetNextTemplateSerialNumber();
    set_serial_number(serial_number);
  }
  return serial_number;
}
 
uint32_t TemplateInfo::GetHash() const {
  uint32_t hash = ComputeUnseededHash(serial_number());
  // Make sure that the hash can be encoded in a Smi in order to make it
  // compatible with Object::GetSimpleHash() and avoid surprises.
  return hash & Smi::kMaxValue;
}
 
// static
MaybeHandle<Object> TemplateInfo::ProbeInstantiationsCache(
    Isolate* isolate, DirectHandle<NativeContext> native_context,
    DirectHandle<TemplateInfo> info, CachingMode caching_mode) {
  DCHECK(info->is_cacheable());
 
  uint32_t serial_number = info->serial_number();
  if (serial_number == kUninitializedSerialNumber) {
    return {};
  }
 
  if (serial_number < kFastTemplateInstantiationsCacheSize) {
    Tagged<FixedArray> fast_cache =
        native_context->fast_template_instantiations_cache();
    Tagged<Object> object = fast_cache->get(serial_number);
    if (IsTheHole(object, isolate)) {
      return {};
    }
    return handle(object, isolate);
  }
  Tagged<EphemeronHashTable> cache =
      native_context->slow_template_instantiations_cache();
  ReadOnlyRoots roots(isolate);
  // Instead of detouring via Object::GetHash() load the hash directly.
  uint32_t hash = info->GetHash();
  InternalIndex entry = cache->FindEntry(isolate, roots, info, hash);
  if (entry.is_found()) {
    return handle(cache->ValueAt(entry), isolate);
  }
  return {};
}
 
// static
void TemplateInfo::CacheTemplateInstantiation(
    Isolate* isolate, DirectHandle<NativeContext> native_context,
    DirectHandle<TemplateInfo> info, CachingMode caching_mode,
    DirectHandle<Object> object) {
  DCHECK(info->is_cacheable());
 
  uint32_t serial_number = info->EnsureHasSerialNumber(isolate);
 
  if (serial_number < kFastTemplateInstantiationsCacheSize) {
    Handle<FixedArray> fast_cache =
        handle(native_context->fast_template_instantiations_cache(), isolate);
    fast_cache->set(serial_number, *object);
    return;
  }
  Handle<EphemeronHashTable> cache =
      handle(native_context->slow_template_instantiations_cache(), isolate);
  if (caching_mode == CachingMode::kUnlimited ||
      (cache->NumberOfElements() < kMaxTemplateInstantiationsCacheSize)) {
    ReadOnlyRoots roots(isolate);
    // Instead of detouring via Object::GetHash() load the hash directly.
    uint32_t hash = info->GetHash();
    auto new_cache =
        EphemeronHashTable::Put(isolate, cache, info, object, hash);
    if (*new_cache != *cache) {
      native_context->set_slow_template_instantiations_cache(*new_cache);
    }
  }
}
 
// static
void TemplateInfo::UncacheTemplateInstantiation(
    Isolate* isolate, DirectHandle<NativeContext> native_context,
    DirectHandle<TemplateInfo> info, CachingMode caching_mode) {
  int serial_number = info->serial_number();
  if (serial_number == kUninitializedSerialNumber) return;
 
  if (serial_number < kFastTemplateInstantiationsCacheSize) {
    Tagged<FixedArray> fast_cache =
        native_context->fast_template_instantiations_cache();
    DCHECK(!IsUndefined(fast_cache->get(serial_number), isolate));
    fast_cache->set(serial_number, ReadOnlyRoots{isolate}.the_hole_value(),
                    SKIP_WRITE_BARRIER);
    return;
  }
  Handle<EphemeronHashTable> cache =
      handle(native_context->slow_template_instantiations_cache(), isolate);
  // Instead of detouring via Object::GetHash() load the hash directly.
  uint32_t hash = info->GetHash();
  bool was_present = false;
  auto new_cache =
      EphemeronHashTable::Remove(isolate, cache, info, &was_present, hash);
  DCHECK(was_present);
  if (!new_cache.is_identical_to(cache)) {
    native_context->set_slow_template_instantiations_cache(*new_cache);
  }
}
 
}  // namespace internal
}  // namespace v8
 
#include "src/objects/object-macros-undef.h"
 
#endif  // V8_OBJECTS_TEMPLATES_INL_H_