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// Copyright 2016 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_IC_HANDLER_CONFIGURATION_H_
#define V8_IC_HANDLER_CONFIGURATION_H_
#include "src/elements-kind.h"
#include "src/field-index.h"
#include "src/globals.h"
#include "src/utils.h"
namespace v8 {
namespace internal {
// A set of bit fields representing Smi handlers for loads.
class LoadHandler {
public:
enum Kind { kForElements, kForFields, kForConstants, kForNonExistent };
class KindBits : public BitField<Kind, 0, 2> {};
// Defines whether access rights check should be done on receiver object.
// Applicable to kForFields, kForConstants and kForNonExistent kinds only when
// loading value from prototype chain. Ignored when loading from holder.
class DoAccessCheckOnReceiverBits
: public BitField<bool, KindBits::kNext, 1> {};
// Defines whether negative lookup check should be done on receiver object.
// Applicable to kForFields, kForConstants and kForNonExistent kinds only when
// loading value from prototype chain. Ignored when loading from holder.
class DoNegativeLookupOnReceiverBits
: public BitField<bool, DoAccessCheckOnReceiverBits::kNext, 1> {};
//
// Encoding when KindBits contains kForConstants.
//
class IsAccessorInfoBits
: public BitField<bool, DoNegativeLookupOnReceiverBits::kNext, 1> {};
// Index of a value entry in the descriptor array.
// +2 here is because each descriptor entry occupies 3 slots in array.
class DescriptorValueIndexBits
: public BitField<unsigned, IsAccessorInfoBits::kNext,
kDescriptorIndexBitCount + 2> {};
// Make sure we don't overflow the smi.
STATIC_ASSERT(DescriptorValueIndexBits::kNext <= kSmiValueSize);
//
// Encoding when KindBits contains kForFields.
//
class IsInobjectBits
: public BitField<bool, DoNegativeLookupOnReceiverBits::kNext, 1> {};
class IsDoubleBits : public BitField<bool, IsInobjectBits::kNext, 1> {};
// +1 here is to cover all possible JSObject header sizes.
class FieldOffsetBits
: public BitField<unsigned, IsDoubleBits::kNext,
kDescriptorIndexBitCount + 1 + kPointerSizeLog2> {};
// Make sure we don't overflow the smi.
STATIC_ASSERT(FieldOffsetBits::kNext <= kSmiValueSize);
//
// Encoding when KindBits contains kForElements.
//
class IsJsArrayBits : public BitField<bool, KindBits::kNext, 1> {};
class ConvertHoleBits : public BitField<bool, IsJsArrayBits::kNext, 1> {};
class ElementsKindBits
: public BitField<ElementsKind, ConvertHoleBits::kNext, 8> {};
// Make sure we don't overflow the smi.
STATIC_ASSERT(ElementsKindBits::kNext <= kSmiValueSize);
// The layout of an Tuple3 handler representing a load of a field from
// prototype when prototype chain checks do not include non-existing lookups
// or access checks.
static const int kHolderCellOffset = Tuple3::kValue1Offset;
static const int kSmiHandlerOffset = Tuple3::kValue2Offset;
static const int kValidityCellOffset = Tuple3::kValue3Offset;
// The layout of an array handler representing a load of a field from
// prototype when prototype chain checks include non-existing lookups and
// access checks.
static const int kSmiHandlerIndex = 0;
static const int kValidityCellIndex = 1;
static const int kHolderCellIndex = 2;
static const int kFirstPrototypeIndex = 3;
// Creates a Smi-handler for loading a field from fast object.
static inline Handle<Object> LoadField(Isolate* isolate,
FieldIndex field_index);
// Creates a Smi-handler for loading a constant from fast object.
static inline Handle<Object> LoadConstant(Isolate* isolate, int descriptor);
// Creates a Smi-handler for loading an Api getter property from fast object.
static inline Handle<Object> LoadApiGetter(Isolate* isolate, int descriptor);
// Sets DoAccessCheckOnReceiverBits in given Smi-handler. The receiver
// check is a part of a prototype chain check.
static inline Handle<Object> EnableAccessCheckOnReceiver(
Isolate* isolate, Handle<Object> smi_handler);
// Sets DoNegativeLookupOnReceiverBits in given Smi-handler. The receiver
// check is a part of a prototype chain check.
static inline Handle<Object> EnableNegativeLookupOnReceiver(
Isolate* isolate, Handle<Object> smi_handler);
// Creates a Smi-handler for loading a non-existent property. Works only as
// a part of prototype chain check.
static inline Handle<Object> LoadNonExistent(
Isolate* isolate, bool do_negative_lookup_on_receiver);
// Creates a Smi-handler for loading an element.
static inline Handle<Object> LoadElement(Isolate* isolate,
ElementsKind elements_kind,
bool convert_hole_to_undefined,
bool is_js_array);
};
// A set of bit fields representing Smi handlers for stores.
class StoreHandler {
public:
enum Kind {
kStoreElement,
kStoreField,
kStoreConstField,
kTransitionToField,
// TODO(ishell): remove once constant field tracking is done.
kTransitionToConstant = kStoreConstField
};
class KindBits : public BitField<Kind, 0, 2> {};
enum FieldRepresentation { kSmi, kDouble, kHeapObject, kTagged };
// Applicable to kStoreField, kTransitionToField and kTransitionToConstant
// kinds.
// Index of a value entry in the descriptor array.
// +2 here is because each descriptor entry occupies 3 slots in array.
class DescriptorValueIndexBits
: public BitField<unsigned, KindBits::kNext,
kDescriptorIndexBitCount + 2> {};
//
// Encoding when KindBits contains kTransitionToConstant.
//
// Make sure we don't overflow the smi.
STATIC_ASSERT(DescriptorValueIndexBits::kNext <= kSmiValueSize);
//
// Encoding when KindBits contains kStoreField or kTransitionToField.
//
class ExtendStorageBits
: public BitField<bool, DescriptorValueIndexBits::kNext, 1> {};
class IsInobjectBits : public BitField<bool, ExtendStorageBits::kNext, 1> {};
class FieldRepresentationBits
: public BitField<FieldRepresentation, IsInobjectBits::kNext, 2> {};
// +1 here is to cover all possible JSObject header sizes.
class FieldOffsetBits
: public BitField<unsigned, FieldRepresentationBits::kNext,
kDescriptorIndexBitCount + 1 + kPointerSizeLog2> {};
// Make sure we don't overflow the smi.
STATIC_ASSERT(FieldOffsetBits::kNext <= kSmiValueSize);
// The layout of an Tuple3 handler representing a transitioning store
// when prototype chain checks do not include non-existing lookups or access
// checks.
static const int kTransitionCellOffset = Tuple3::kValue1Offset;
static const int kSmiHandlerOffset = Tuple3::kValue2Offset;
static const int kValidityCellOffset = Tuple3::kValue3Offset;
// The layout of an array handler representing a transitioning store
// when prototype chain checks include non-existing lookups and access checks.
static const int kSmiHandlerIndex = 0;
static const int kValidityCellIndex = 1;
static const int kTransitionCellIndex = 2;
static const int kFirstPrototypeIndex = 3;
// Creates a Smi-handler for storing a field to fast object.
static inline Handle<Object> StoreField(Isolate* isolate, int descriptor,
FieldIndex field_index,
PropertyConstness constness,
Representation representation);
// Creates a Smi-handler for transitioning store to a field.
static inline Handle<Object> TransitionToField(Isolate* isolate,
int descriptor,
FieldIndex field_index,
Representation representation,
bool extend_storage);
// Creates a Smi-handler for transitioning store to a constant field (in this
// case the only thing that needs to be done is an update of a map).
static inline Handle<Object> TransitionToConstant(Isolate* isolate,
int descriptor);
private:
static inline Handle<Object> StoreField(Isolate* isolate, Kind kind,
int descriptor,
FieldIndex field_index,
Representation representation,
bool extend_storage);
};
} // namespace internal
} // namespace v8
#endif // V8_IC_HANDLER_CONFIGURATION_H_
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