5dffa35350
R=yangguo@chromium.org LOG=n Review URL: https://codereview.chromium.org/1507273002 Cr-Commit-Position: refs/heads/master@{#32695}
566 lines
28 KiB
C++
566 lines
28 KiB
C++
// Copyright 2012 the V8 project authors. All rights reserved.
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// Use of this source code is governed by a BSD-style license that can be
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// found in the LICENSE file.
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#ifndef V8_CONTEXTS_H_
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#define V8_CONTEXTS_H_
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#include "src/heap/heap.h"
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#include "src/objects.h"
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namespace v8 {
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namespace internal {
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enum ContextLookupFlags {
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FOLLOW_CONTEXT_CHAIN = 1 << 0,
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FOLLOW_PROTOTYPE_CHAIN = 1 << 1,
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STOP_AT_DECLARATION_SCOPE = 1 << 2,
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SKIP_WITH_CONTEXT = 1 << 3,
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DONT_FOLLOW_CHAINS = 0,
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FOLLOW_CHAINS = FOLLOW_CONTEXT_CHAIN | FOLLOW_PROTOTYPE_CHAIN,
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LEXICAL_TEST =
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FOLLOW_CONTEXT_CHAIN | STOP_AT_DECLARATION_SCOPE | SKIP_WITH_CONTEXT,
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};
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// ES5 10.2 defines lexical environments with mutable and immutable bindings.
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// Immutable bindings have two states, initialized and uninitialized, and
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// their state is changed by the InitializeImmutableBinding method. The
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// BindingFlags enum represents information if a binding has definitely been
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// initialized. A mutable binding does not need to be checked and thus has
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// the BindingFlag MUTABLE_IS_INITIALIZED.
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//
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// There are two possibilities for immutable bindings
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// * 'const' declared variables. They are initialized when evaluating the
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// corresponding declaration statement. They need to be checked for being
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// initialized and thus get the flag IMMUTABLE_CHECK_INITIALIZED.
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// * The function name of a named function literal. The binding is immediately
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// initialized when entering the function and thus does not need to be
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// checked. it gets the BindingFlag IMMUTABLE_IS_INITIALIZED.
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// Accessing an uninitialized binding produces the undefined value.
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//
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// The harmony proposal for block scoped bindings also introduces the
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// uninitialized state for mutable bindings.
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// * A 'let' declared variable. They are initialized when evaluating the
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// corresponding declaration statement. They need to be checked for being
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// initialized and thus get the flag MUTABLE_CHECK_INITIALIZED.
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// * A 'var' declared variable. It is initialized immediately upon creation
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// and thus doesn't need to be checked. It gets the flag
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// MUTABLE_IS_INITIALIZED.
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// * Catch bound variables, function parameters and variables introduced by
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// function declarations are initialized immediately and do not need to be
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// checked. Thus they get the flag MUTABLE_IS_INITIALIZED.
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// Immutable bindings in harmony mode get the _HARMONY flag variants. Accessing
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// an uninitialized binding produces a reference error.
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//
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// In V8 uninitialized bindings are set to the hole value upon creation and set
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// to a different value upon initialization.
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enum BindingFlags {
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MUTABLE_IS_INITIALIZED,
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MUTABLE_CHECK_INITIALIZED,
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IMMUTABLE_IS_INITIALIZED,
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IMMUTABLE_CHECK_INITIALIZED,
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IMMUTABLE_IS_INITIALIZED_HARMONY,
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IMMUTABLE_CHECK_INITIALIZED_HARMONY,
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MISSING_BINDING
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};
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// Heap-allocated activation contexts.
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//
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// Contexts are implemented as FixedArray objects; the Context
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// class is a convenience interface casted on a FixedArray object.
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//
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// Note: Context must have no virtual functions and Context objects
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// must always be allocated via Heap::AllocateContext() or
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// Factory::NewContext.
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#define NATIVE_CONTEXT_INTRINSIC_FUNCTIONS(V) \
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V(CONCAT_ITERABLE_TO_ARRAY_INDEX, JSFunction, concat_iterable_to_array) \
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V(GET_TEMPLATE_CALL_SITE_INDEX, JSFunction, get_template_call_site) \
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V(MAKE_RANGE_ERROR_INDEX, JSFunction, make_range_error) \
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V(MAKE_TYPE_ERROR_INDEX, JSFunction, make_type_error) \
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V(REFLECT_APPLY_INDEX, JSFunction, reflect_apply) \
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V(REFLECT_CONSTRUCT_INDEX, JSFunction, reflect_construct) \
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V(SPREAD_ARGUMENTS_INDEX, JSFunction, spread_arguments) \
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V(SPREAD_ITERABLE_INDEX, JSFunction, spread_iterable)
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#define NATIVE_CONTEXT_JS_BUILTINS(V) \
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V(APPLY_PREPARE_BUILTIN_INDEX, JSFunction, apply_prepare_builtin) \
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V(CONCAT_ITERABLE_TO_ARRAY_BUILTIN_INDEX, JSFunction, \
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concat_iterable_to_array_builtin) \
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V(REFLECT_APPLY_PREPARE_BUILTIN_INDEX, JSFunction, \
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reflect_apply_prepare_builtin) \
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V(REFLECT_CONSTRUCT_PREPARE_BUILTIN_INDEX, JSFunction, \
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reflect_construct_prepare_builtin)
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#define NATIVE_CONTEXT_IMPORTED_FIELDS(V) \
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V(ARRAY_CONCAT_INDEX, JSFunction, array_concat) \
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V(ARRAY_POP_INDEX, JSFunction, array_pop) \
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V(ARRAY_PUSH_INDEX, JSFunction, array_push) \
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V(ARRAY_SHIFT_INDEX, JSFunction, array_shift) \
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V(ARRAY_SPLICE_INDEX, JSFunction, array_splice) \
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V(ARRAY_SLICE_INDEX, JSFunction, array_slice) \
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V(ARRAY_UNSHIFT_INDEX, JSFunction, array_unshift) \
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V(ARRAY_VALUES_ITERATOR_INDEX, JSFunction, array_values_iterator) \
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V(CREATE_DATE_FUN_INDEX, JSFunction, create_date_fun) \
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V(DERIVED_GET_TRAP_INDEX, JSFunction, derived_get_trap) \
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V(ERROR_FUNCTION_INDEX, JSFunction, error_function) \
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V(EVAL_ERROR_FUNCTION_INDEX, JSFunction, eval_error_function) \
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V(GET_STACK_TRACE_LINE_INDEX, JSFunction, get_stack_trace_line_fun) \
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V(GLOBAL_EVAL_FUN_INDEX, JSFunction, global_eval_fun) \
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V(JSON_SERIALIZE_ADAPTER_INDEX, JSFunction, json_serialize_adapter) \
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V(MAKE_ERROR_FUNCTION_INDEX, JSFunction, make_error_function) \
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V(MAP_DELETE_METHOD_INDEX, JSFunction, map_delete) \
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V(MAP_GET_METHOD_INDEX, JSFunction, map_get) \
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V(MAP_HAS_METHOD_INDEX, JSFunction, map_has) \
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V(MAP_SET_METHOD_INDEX, JSFunction, map_set) \
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V(MESSAGE_GET_COLUMN_NUMBER_INDEX, JSFunction, message_get_column_number) \
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V(MESSAGE_GET_LINE_NUMBER_INDEX, JSFunction, message_get_line_number) \
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V(MESSAGE_GET_SOURCE_LINE_INDEX, JSFunction, message_get_source_line) \
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V(NATIVE_OBJECT_GET_NOTIFIER_INDEX, JSFunction, native_object_get_notifier) \
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V(NATIVE_OBJECT_NOTIFIER_PERFORM_CHANGE, JSFunction, \
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native_object_notifier_perform_change) \
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V(NATIVE_OBJECT_OBSERVE_INDEX, JSFunction, native_object_observe) \
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V(NO_SIDE_EFFECTS_TO_STRING_FUN_INDEX, JSFunction, \
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no_side_effects_to_string_fun) \
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V(OBJECT_VALUE_OF, JSFunction, object_value_of) \
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V(OBJECT_TO_STRING, JSFunction, object_to_string) \
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V(OBSERVERS_BEGIN_SPLICE_INDEX, JSFunction, observers_begin_perform_splice) \
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V(OBSERVERS_END_SPLICE_INDEX, JSFunction, observers_end_perform_splice) \
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V(OBSERVERS_ENQUEUE_SPLICE_INDEX, JSFunction, observers_enqueue_splice) \
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V(OBSERVERS_NOTIFY_CHANGE_INDEX, JSFunction, observers_notify_change) \
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V(PROMISE_CATCH_INDEX, JSFunction, promise_catch) \
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V(PROMISE_CHAIN_INDEX, JSFunction, promise_chain) \
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V(PROMISE_CREATE_INDEX, JSFunction, promise_create) \
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V(PROMISE_HAS_USER_DEFINED_REJECT_HANDLER_INDEX, JSFunction, \
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promise_has_user_defined_reject_handler) \
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V(PROMISE_REJECT_INDEX, JSFunction, promise_reject) \
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V(PROMISE_RESOLVE_INDEX, JSFunction, promise_resolve) \
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V(PROMISE_THEN_INDEX, JSFunction, promise_then) \
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V(PROXY_ENUMERATE_INDEX, JSFunction, proxy_enumerate) \
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V(RANGE_ERROR_FUNCTION_INDEX, JSFunction, range_error_function) \
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V(REFERENCE_ERROR_FUNCTION_INDEX, JSFunction, reference_error_function) \
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V(SET_ADD_METHOD_INDEX, JSFunction, set_add) \
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V(SET_DELETE_METHOD_INDEX, JSFunction, set_delete) \
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V(SET_HAS_METHOD_INDEX, JSFunction, set_has) \
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V(STACK_OVERFLOW_BOILERPLATE_INDEX, JSObject, stack_overflow_boilerplate) \
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V(SYNTAX_ERROR_FUNCTION_INDEX, JSFunction, syntax_error_function) \
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V(TYPE_ERROR_FUNCTION_INDEX, JSFunction, type_error_function) \
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V(URI_ERROR_FUNCTION_INDEX, JSFunction, uri_error_function) \
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NATIVE_CONTEXT_JS_BUILTINS(V)
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#define NATIVE_CONTEXT_FIELDS(V) \
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V(GLOBAL_PROXY_INDEX, JSObject, global_proxy_object) \
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V(EMBEDDER_DATA_INDEX, FixedArray, embedder_data) \
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/* Below is alpha-sorted */ \
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V(ALLOW_CODE_GEN_FROM_STRINGS_INDEX, Object, allow_code_gen_from_strings) \
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V(ARRAY_BUFFER_FUN_INDEX, JSFunction, array_buffer_fun) \
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V(ARRAY_BUFFER_MAP_INDEX, Map, array_buffer_map) \
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V(ARRAY_FUNCTION_INDEX, JSFunction, array_function) \
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V(BOOL16X8_FUNCTION_INDEX, JSFunction, bool16x8_function) \
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V(BOOL32X4_FUNCTION_INDEX, JSFunction, bool32x4_function) \
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V(BOOL8X16_FUNCTION_INDEX, JSFunction, bool8x16_function) \
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V(BOOLEAN_FUNCTION_INDEX, JSFunction, boolean_function) \
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V(BOUND_FUNCTION_WITH_CONSTRUCTOR_MAP_INDEX, Map, \
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bound_function_with_constructor_map) \
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V(BOUND_FUNCTION_WITHOUT_CONSTRUCTOR_MAP_INDEX, Map, \
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bound_function_without_constructor_map) \
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V(CALL_AS_CONSTRUCTOR_DELEGATE_INDEX, JSFunction, \
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call_as_constructor_delegate) \
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V(CALL_AS_FUNCTION_DELEGATE_INDEX, JSFunction, call_as_function_delegate) \
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V(CONTEXT_EXTENSION_FUNCTION_INDEX, JSFunction, context_extension_function) \
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V(DATA_VIEW_FUN_INDEX, JSFunction, data_view_fun) \
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V(DATE_FUNCTION_INDEX, JSFunction, date_function) \
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V(ERROR_MESSAGE_FOR_CODE_GEN_FROM_STRINGS_INDEX, Object, \
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error_message_for_code_gen_from_strings) \
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V(ERRORS_THROWN_INDEX, Smi, errors_thrown) \
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V(EXTRAS_EXPORTS_OBJECT_INDEX, JSObject, extras_binding_object) \
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V(EXTRAS_UTILS_OBJECT_INDEX, JSObject, extras_utils_object) \
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V(FAST_ALIASED_ARGUMENTS_MAP_INDEX, Map, fast_aliased_arguments_map) \
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V(FLOAT32_ARRAY_FUN_INDEX, JSFunction, float32_array_fun) \
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V(FLOAT32X4_FUNCTION_INDEX, JSFunction, float32x4_function) \
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V(FLOAT64_ARRAY_FUN_INDEX, JSFunction, float64_array_fun) \
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V(FUNCTION_CACHE_INDEX, ObjectHashTable, function_cache) \
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V(FUNCTION_FUNCTION_INDEX, JSFunction, function_function) \
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V(GENERATOR_FUNCTION_FUNCTION_INDEX, JSFunction, \
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generator_function_function) \
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V(GENERATOR_OBJECT_PROTOTYPE_MAP_INDEX, Map, generator_object_prototype_map) \
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V(INITIAL_ARRAY_PROTOTYPE_INDEX, JSObject, initial_array_prototype) \
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V(INITIAL_OBJECT_PROTOTYPE_INDEX, JSObject, initial_object_prototype) \
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V(INT16_ARRAY_FUN_INDEX, JSFunction, int16_array_fun) \
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V(INT16X8_FUNCTION_INDEX, JSFunction, int16x8_function) \
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V(INT32_ARRAY_FUN_INDEX, JSFunction, int32_array_fun) \
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V(INT32X4_FUNCTION_INDEX, JSFunction, int32x4_function) \
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V(INT8_ARRAY_FUN_INDEX, JSFunction, int8_array_fun) \
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V(INT8X16_FUNCTION_INDEX, JSFunction, int8x16_function) \
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V(INTERNAL_ARRAY_FUNCTION_INDEX, JSFunction, internal_array_function) \
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V(ITERATOR_RESULT_MAP_INDEX, Map, iterator_result_map) \
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V(JS_ARRAY_MAPS_INDEX, Object, js_array_maps) \
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V(JS_ARRAY_STRONG_MAPS_INDEX, Object, js_array_strong_maps) \
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V(JS_MAP_FUN_INDEX, JSFunction, js_map_fun) \
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V(JS_MAP_MAP_INDEX, Map, js_map_map) \
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V(JS_OBJECT_STRONG_MAP_INDEX, Map, js_object_strong_map) \
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V(JS_SET_FUN_INDEX, JSFunction, js_set_fun) \
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V(JS_SET_MAP_INDEX, Map, js_set_map) \
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V(JS_WEAK_MAP_FUN_INDEX, JSFunction, js_weak_map_fun) \
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V(JS_WEAK_SET_FUN_INDEX, JSFunction, js_weak_set_fun) \
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V(MAP_CACHE_INDEX, Object, map_cache) \
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V(MAP_ITERATOR_MAP_INDEX, Map, map_iterator_map) \
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V(STRING_ITERATOR_MAP_INDEX, Map, string_iterator_map) \
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V(MESSAGE_LISTENERS_INDEX, JSObject, message_listeners) \
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V(NATIVES_UTILS_OBJECT_INDEX, Object, natives_utils_object) \
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V(NORMALIZED_MAP_CACHE_INDEX, Object, normalized_map_cache) \
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V(NUMBER_FUNCTION_INDEX, JSFunction, number_function) \
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V(OBJECT_FUNCTION_INDEX, JSFunction, object_function) \
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V(OBJECT_FUNCTION_PROTOTYPE_MAP_INDEX, Map, object_function_prototype_map) \
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V(OPAQUE_REFERENCE_FUNCTION_INDEX, JSFunction, opaque_reference_function) \
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V(PROXY_CALLABLE_MAP_INDEX, Map, proxy_callable_map) \
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V(PROXY_CONSTRUCTOR_MAP_INDEX, Map, proxy_constructor_map) \
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V(PROXY_FUNCTION_INDEX, JSFunction, proxy_function) \
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V(PROXY_FUNCTION_MAP_INDEX, Map, proxy_function_map) \
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V(PROXY_MAP_INDEX, Map, proxy_map) \
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V(REGEXP_FUNCTION_INDEX, JSFunction, regexp_function) \
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V(REGEXP_RESULT_MAP_INDEX, Map, regexp_result_map) \
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V(SCRIPT_CONTEXT_TABLE_INDEX, ScriptContextTable, script_context_table) \
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V(SCRIPT_FUNCTION_INDEX, JSFunction, script_function) \
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V(SECURITY_TOKEN_INDEX, Object, security_token) \
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V(SET_ITERATOR_MAP_INDEX, Map, set_iterator_map) \
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V(SHARED_ARRAY_BUFFER_FUN_INDEX, JSFunction, shared_array_buffer_fun) \
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V(SLOPPY_ARGUMENTS_MAP_INDEX, Map, sloppy_arguments_map) \
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V(SLOPPY_FUNCTION_MAP_INDEX, Map, sloppy_function_map) \
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V(SLOPPY_FUNCTION_WITHOUT_PROTOTYPE_MAP_INDEX, Map, \
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sloppy_function_without_prototype_map) \
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V(SLOPPY_FUNCTION_WITH_READONLY_PROTOTYPE_MAP_INDEX, Map, \
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sloppy_function_with_readonly_prototype_map) \
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V(SLOPPY_GENERATOR_FUNCTION_MAP_INDEX, Map, sloppy_generator_function_map) \
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V(SLOW_ALIASED_ARGUMENTS_MAP_INDEX, Map, slow_aliased_arguments_map) \
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V(STRICT_ARGUMENTS_MAP_INDEX, Map, strict_arguments_map) \
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V(STRICT_FUNCTION_MAP_INDEX, Map, strict_function_map) \
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V(STRICT_FUNCTION_WITHOUT_PROTOTYPE_MAP_INDEX, Map, \
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strict_function_without_prototype_map) \
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V(STRICT_GENERATOR_FUNCTION_MAP_INDEX, Map, strict_generator_function_map) \
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V(STRING_FUNCTION_INDEX, JSFunction, string_function) \
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V(STRING_FUNCTION_PROTOTYPE_MAP_INDEX, Map, string_function_prototype_map) \
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V(STRONG_CONSTRUCTOR_MAP_INDEX, Map, strong_constructor_map) \
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V(STRONG_FUNCTION_MAP_INDEX, Map, strong_function_map) \
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V(STRONG_GENERATOR_FUNCTION_MAP_INDEX, Map, strong_generator_function_map) \
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V(STRONG_MAP_CACHE_INDEX, Object, strong_map_cache) \
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V(SYMBOL_FUNCTION_INDEX, JSFunction, symbol_function) \
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V(UINT16_ARRAY_FUN_INDEX, JSFunction, uint16_array_fun) \
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V(UINT16X8_FUNCTION_INDEX, JSFunction, uint16x8_function) \
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V(UINT32_ARRAY_FUN_INDEX, JSFunction, uint32_array_fun) \
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V(UINT32X4_FUNCTION_INDEX, JSFunction, uint32x4_function) \
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V(UINT8_ARRAY_FUN_INDEX, JSFunction, uint8_array_fun) \
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V(UINT8_CLAMPED_ARRAY_FUN_INDEX, JSFunction, uint8_clamped_array_fun) \
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V(UINT8X16_FUNCTION_INDEX, JSFunction, uint8x16_function) \
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NATIVE_CONTEXT_INTRINSIC_FUNCTIONS(V) \
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NATIVE_CONTEXT_IMPORTED_FIELDS(V)
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// A table of all script contexts. Every loaded top-level script with top-level
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// lexical declarations contributes its ScriptContext into this table.
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//
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// The table is a fixed array, its first slot is the current used count and
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// the subsequent slots 1..used contain ScriptContexts.
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class ScriptContextTable : public FixedArray {
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public:
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// Conversions.
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static inline ScriptContextTable* cast(Object* context);
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struct LookupResult {
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int context_index;
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int slot_index;
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VariableMode mode;
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InitializationFlag init_flag;
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MaybeAssignedFlag maybe_assigned_flag;
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};
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inline int used() const;
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inline void set_used(int used);
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static inline Handle<Context> GetContext(Handle<ScriptContextTable> table,
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int i);
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// Lookup a variable `name` in a ScriptContextTable.
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// If it returns true, the variable is found and `result` contains
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// valid information about its location.
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// If it returns false, `result` is untouched.
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MUST_USE_RESULT
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static bool Lookup(Handle<ScriptContextTable> table, Handle<String> name,
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LookupResult* result);
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MUST_USE_RESULT
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static Handle<ScriptContextTable> Extend(Handle<ScriptContextTable> table,
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Handle<Context> script_context);
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static int GetContextOffset(int context_index) {
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return kFirstContextOffset + context_index * kPointerSize;
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}
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private:
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static const int kUsedSlot = 0;
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static const int kFirstContextSlot = kUsedSlot + 1;
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static const int kFirstContextOffset =
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FixedArray::kHeaderSize + kFirstContextSlot * kPointerSize;
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DISALLOW_IMPLICIT_CONSTRUCTORS(ScriptContextTable);
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};
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// JSFunctions are pairs (context, function code), sometimes also called
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// closures. A Context object is used to represent function contexts and
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// dynamically pushed 'with' contexts (or 'scopes' in ECMA-262 speak).
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//
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// At runtime, the contexts build a stack in parallel to the execution
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// stack, with the top-most context being the current context. All contexts
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// have the following slots:
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//
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// [ closure ] This is the current function. It is the same for all
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// contexts inside a function. It provides access to the
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// incoming context (i.e., the outer context, which may
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// or may not become the current function's context), and
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// it provides access to the functions code and thus it's
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// scope information, which in turn contains the names of
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// statically allocated context slots. The names are needed
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// for dynamic lookups in the presence of 'with' or 'eval'.
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//
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// [ previous ] A pointer to the previous context. It is NULL for
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// function contexts, and non-NULL for 'with' contexts.
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// Used to implement the 'with' statement.
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//
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// [ extension ] A pointer to an extension JSObject, or "the hole". Used to
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// implement 'with' statements and dynamic declarations
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// (through 'eval'). The object in a 'with' statement is
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// stored in the extension slot of a 'with' context.
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// Dynamically declared variables/functions are also added
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// to lazily allocated extension object. Context::Lookup
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// searches the extension object for properties.
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// For script and block contexts, contains the respective
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// ScopeInfo. For block contexts representing sloppy declaration
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// block scopes, it may also be a struct being a
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// SloppyBlockWithEvalContextExtension, pairing the ScopeInfo
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// with an extension object.
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// For module contexts, points back to the respective JSModule.
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//
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// [ global_object ] A pointer to the global object. Provided for quick
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// access to the global object from inside the code (since
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// we always have a context pointer).
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//
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// In addition, function contexts may have statically allocated context slots
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// to store local variables/functions that are accessed from inner functions
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// (via static context addresses) or through 'eval' (dynamic context lookups).
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// The native context contains additional slots for fast access to native
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// properties.
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//
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// Finally, with Harmony scoping, the JSFunction representing a top level
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// script will have the ScriptContext rather than a FunctionContext.
|
|
// Script contexts from all top-level scripts are gathered in
|
|
// ScriptContextTable.
|
|
|
|
class Context: public FixedArray {
|
|
public:
|
|
// Conversions.
|
|
static inline Context* cast(Object* context);
|
|
|
|
// The default context slot layout; indices are FixedArray slot indices.
|
|
enum {
|
|
// These slots are in all contexts.
|
|
CLOSURE_INDEX,
|
|
PREVIOUS_INDEX,
|
|
// The extension slot is used for either the global object (in native
|
|
// contexts), eval extension object (function contexts), subject of with
|
|
// (with contexts), or the variable name (catch contexts), the serialized
|
|
// scope info (block contexts), or the module instance (module contexts).
|
|
EXTENSION_INDEX,
|
|
NATIVE_CONTEXT_INDEX,
|
|
|
|
// These slots are only in native contexts.
|
|
#define NATIVE_CONTEXT_SLOT(index, type, name) index,
|
|
NATIVE_CONTEXT_FIELDS(NATIVE_CONTEXT_SLOT)
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|
#undef NATIVE_CONTEXT_SLOT
|
|
|
|
// Properties from here are treated as weak references by the full GC.
|
|
// Scavenge treats them as strong references.
|
|
OPTIMIZED_FUNCTIONS_LIST, // Weak.
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|
OPTIMIZED_CODE_LIST, // Weak.
|
|
DEOPTIMIZED_CODE_LIST, // Weak.
|
|
NEXT_CONTEXT_LINK, // Weak.
|
|
|
|
// Total number of slots.
|
|
NATIVE_CONTEXT_SLOTS,
|
|
FIRST_WEAK_SLOT = OPTIMIZED_FUNCTIONS_LIST,
|
|
|
|
MIN_CONTEXT_SLOTS = GLOBAL_PROXY_INDEX,
|
|
// This slot holds the thrown value in catch contexts.
|
|
THROWN_OBJECT_INDEX = MIN_CONTEXT_SLOTS,
|
|
};
|
|
|
|
void IncrementErrorsThrown();
|
|
int GetErrorsThrown();
|
|
|
|
// Direct slot access.
|
|
inline JSFunction* closure();
|
|
inline void set_closure(JSFunction* closure);
|
|
|
|
inline Context* previous();
|
|
inline void set_previous(Context* context);
|
|
|
|
inline bool has_extension();
|
|
inline HeapObject* extension();
|
|
inline void set_extension(HeapObject* object);
|
|
JSObject* extension_object();
|
|
JSReceiver* extension_receiver();
|
|
ScopeInfo* scope_info();
|
|
String* catch_name();
|
|
|
|
inline JSModule* module();
|
|
inline void set_module(JSModule* module);
|
|
|
|
// Get the context where var declarations will be hoisted to, which
|
|
// may be the context itself.
|
|
Context* declaration_context();
|
|
bool is_declaration_context();
|
|
|
|
// Returns a JSGlobalProxy object or null.
|
|
JSObject* global_proxy();
|
|
void set_global_proxy(JSObject* global);
|
|
|
|
// Get the JSGlobalObject object.
|
|
JSGlobalObject* global_object();
|
|
|
|
// Get the script context by traversing the context chain.
|
|
Context* script_context();
|
|
|
|
// Compute the native context.
|
|
inline Context* native_context();
|
|
inline void set_native_context(Context* context);
|
|
|
|
// Predicates for context types. IsNativeContext is also defined on Object
|
|
// because we frequently have to know if arbitrary objects are natives
|
|
// contexts.
|
|
inline bool IsNativeContext();
|
|
inline bool IsFunctionContext();
|
|
inline bool IsCatchContext();
|
|
inline bool IsWithContext();
|
|
inline bool IsBlockContext();
|
|
inline bool IsModuleContext();
|
|
inline bool IsScriptContext();
|
|
|
|
inline bool HasSameSecurityTokenAs(Context* that);
|
|
|
|
// Initializes global variable bindings in given script context.
|
|
void InitializeGlobalSlots();
|
|
|
|
// A native context holds a list of all functions with optimized code.
|
|
void AddOptimizedFunction(JSFunction* function);
|
|
void RemoveOptimizedFunction(JSFunction* function);
|
|
void SetOptimizedFunctionsListHead(Object* head);
|
|
Object* OptimizedFunctionsListHead();
|
|
|
|
// The native context also stores a list of all optimized code and a
|
|
// list of all deoptimized code, which are needed by the deoptimizer.
|
|
void AddOptimizedCode(Code* code);
|
|
void SetOptimizedCodeListHead(Object* head);
|
|
Object* OptimizedCodeListHead();
|
|
void SetDeoptimizedCodeListHead(Object* head);
|
|
Object* DeoptimizedCodeListHead();
|
|
|
|
Handle<Object> ErrorMessageForCodeGenerationFromStrings();
|
|
|
|
static int ImportedFieldIndexForName(Handle<String> name);
|
|
static int IntrinsicIndexForName(Handle<String> name);
|
|
|
|
static bool IsJSBuiltin(Handle<Context> native_context,
|
|
Handle<JSFunction> function);
|
|
|
|
#define NATIVE_CONTEXT_FIELD_ACCESSORS(index, type, name) \
|
|
inline void set_##name(type* value); \
|
|
inline bool is_##name(type* value); \
|
|
inline type* name();
|
|
NATIVE_CONTEXT_FIELDS(NATIVE_CONTEXT_FIELD_ACCESSORS)
|
|
#undef NATIVE_CONTEXT_FIELD_ACCESSORS
|
|
|
|
// Lookup the slot called name, starting with the current context.
|
|
// There are three possibilities:
|
|
//
|
|
// 1) result->IsContext():
|
|
// The binding was found in a context. *index is always the
|
|
// non-negative slot index. *attributes is NONE for var and let
|
|
// declarations, READ_ONLY for const declarations (never ABSENT).
|
|
//
|
|
// 2) result->IsJSObject():
|
|
// The binding was found as a named property in a context extension
|
|
// object (i.e., was introduced via eval), as a property on the subject
|
|
// of with, or as a property of the global object. *index is -1 and
|
|
// *attributes is not ABSENT.
|
|
//
|
|
// 3) result.is_null():
|
|
// There was no binding found, *index is always -1 and *attributes is
|
|
// always ABSENT.
|
|
Handle<Object> Lookup(Handle<String> name,
|
|
ContextLookupFlags flags,
|
|
int* index,
|
|
PropertyAttributes* attributes,
|
|
BindingFlags* binding_flags);
|
|
|
|
// Code generation support.
|
|
static int SlotOffset(int index) {
|
|
return kHeaderSize + index * kPointerSize - kHeapObjectTag;
|
|
}
|
|
|
|
static int FunctionMapIndex(LanguageMode language_mode, FunctionKind kind) {
|
|
if (IsGeneratorFunction(kind)) {
|
|
return is_strong(language_mode) ? STRONG_GENERATOR_FUNCTION_MAP_INDEX :
|
|
is_strict(language_mode) ? STRICT_GENERATOR_FUNCTION_MAP_INDEX
|
|
: SLOPPY_GENERATOR_FUNCTION_MAP_INDEX;
|
|
}
|
|
|
|
if (IsClassConstructor(kind)) {
|
|
// Use strict function map (no own "caller" / "arguments")
|
|
return is_strong(language_mode) ? STRONG_CONSTRUCTOR_MAP_INDEX
|
|
: STRICT_FUNCTION_MAP_INDEX;
|
|
}
|
|
|
|
if (IsArrowFunction(kind) || IsConciseMethod(kind) ||
|
|
IsAccessorFunction(kind)) {
|
|
return is_strong(language_mode)
|
|
? STRONG_FUNCTION_MAP_INDEX
|
|
: STRICT_FUNCTION_WITHOUT_PROTOTYPE_MAP_INDEX;
|
|
}
|
|
|
|
return is_strong(language_mode) ? STRONG_FUNCTION_MAP_INDEX :
|
|
is_strict(language_mode) ? STRICT_FUNCTION_MAP_INDEX
|
|
: SLOPPY_FUNCTION_MAP_INDEX;
|
|
}
|
|
|
|
static const int kSize = kHeaderSize + NATIVE_CONTEXT_SLOTS * kPointerSize;
|
|
static const int kNotFound = -1;
|
|
|
|
// GC support.
|
|
typedef FixedBodyDescriptor<
|
|
kHeaderSize, kSize, kSize> ScavengeBodyDescriptor;
|
|
|
|
typedef FixedBodyDescriptor<
|
|
kHeaderSize,
|
|
kHeaderSize + FIRST_WEAK_SLOT * kPointerSize,
|
|
kSize> MarkCompactBodyDescriptor;
|
|
|
|
private:
|
|
#ifdef DEBUG
|
|
// Bootstrapping-aware type checks.
|
|
static bool IsBootstrappingOrNativeContext(Isolate* isolate, Object* object);
|
|
static bool IsBootstrappingOrValidParentContext(Object* object, Context* kid);
|
|
#endif
|
|
|
|
STATIC_ASSERT(kHeaderSize == Internals::kContextHeaderSize);
|
|
STATIC_ASSERT(EMBEDDER_DATA_INDEX == Internals::kContextEmbedderDataIndex);
|
|
};
|
|
|
|
} // namespace internal
|
|
} // namespace v8
|
|
|
|
#endif // V8_CONTEXTS_H_
|