/**
* Resolve syntactic reference.
*
* @return if reference was resolved successfully,
* pointer to lexical environment - reference's base,
* else - NULL.
*/
ecma_object_t *
ecma_op_resolve_reference_base (ecma_object_t *lex_env_p, /**< starting lexical environment */
ecma_string_t *name_p) /**< identifier's name */
{
JERRY_ASSERT (lex_env_p != NULL);
ecma_object_t *lex_env_iter_p = lex_env_p;
while (lex_env_iter_p != NULL)
{
#if ENABLED (JERRY_ES2015_CLASS)
if (ecma_get_lex_env_type (lex_env_iter_p) == ECMA_LEXICAL_ENVIRONMENT_SUPER_OBJECT_BOUND)
{
lex_env_iter_p = ecma_get_lex_env_outer_reference (lex_env_iter_p);
JERRY_ASSERT (lex_env_iter_p != NULL);
}
#endif /* ENABLED (JERRY_ES2015_CLASS) */
if (ecma_op_has_binding (lex_env_iter_p, name_p))
{
return lex_env_iter_p;
}
lex_env_iter_p = ecma_get_lex_env_outer_reference (lex_env_iter_p);
}
return NULL;
} /* ecma_op_resolve_reference_base */
/**
* Resolve syntactic reference.
*
* @return if reference was resolved successfully,
* pointer to lexical environment - reference's base,
* else - NULL.
*/
ecma_object_t *
ecma_op_resolve_reference_base (ecma_object_t *lex_env_p, /**< starting lexical environment */
ecma_string_t *name_p) /**< identifier's name */
{
JERRY_ASSERT (lex_env_p != NULL);
ecma_object_t *lex_env_iter_p = lex_env_p;
while (lex_env_iter_p != NULL)
{
if (ecma_op_has_binding (lex_env_iter_p, name_p))
{
return lex_env_iter_p;
}
lex_env_iter_p = ecma_get_lex_env_outer_reference (lex_env_iter_p);
}
return NULL;
} /* ecma_op_resolve_reference_base */
/**
* 'Variable declaration' opcode handler.
*
* See also: ECMA-262 v5, 10.5 - Declaration binding instantiation (block 8).
*
* @return ecma value
* Returned value is simple and so need not be freed.
* However, ecma_free_value may be called for it, but it is a no-op.
*/
ecma_value_t
vm_var_decl (vm_frame_ctx_t *frame_ctx_p, /**< interpreter context */
ecma_string_t *var_name_str_p) /**< variable name */
{
if (!ecma_op_has_binding (frame_ctx_p->lex_env_p, var_name_str_p))
{
const bool is_configurable_bindings = frame_ctx_p->is_eval_code;
ecma_value_t completion_value = ecma_op_create_mutable_binding (frame_ctx_p->lex_env_p,
var_name_str_p,
is_configurable_bindings);
JERRY_ASSERT (ecma_is_value_empty (completion_value));
/* Skipping SetMutableBinding as we have already checked that there were not
* any binding with specified name in current lexical environment
* and CreateMutableBinding sets the created binding's value to undefined */
JERRY_ASSERT (ecma_is_value_undefined (ecma_op_get_binding_value (frame_ctx_p->lex_env_p,
var_name_str_p,
true)));
}
return ecma_make_simple_value (ECMA_SIMPLE_VALUE_EMPTY);
} /* vm_var_decl */
/**
* Setup variables for arguments listed in formal parameter list,
* and, if necessary, Arguments object with 'arguments' binding.
*
* See also:
* Declaration binding instantiation (ECMA-262 v5, 10.5), block 4 and 7
*
* @return completion value
* Returned value must be freed with ecma_free_completion_value
*/
static ecma_completion_value_t
ecma_function_call_setup_args_variables (ecma_object_t *func_obj_p, /**< Function object */
ecma_object_t *env_p, /**< lexical environment */
const ecma_value_t *arguments_list_p, /**< arguments list */
ecma_length_t arguments_list_len, /**< length of argument list */
bool is_strict, /**< flag indicating strict mode */
bool do_instantiate_arguments_object) /**< flag indicating whether
* Arguments object should be
* instantiated */
{
ecma_property_t *formal_parameters_prop_p = ecma_get_internal_property (func_obj_p,
ECMA_INTERNAL_PROPERTY_FORMAL_PARAMETERS);
ecma_collection_header_t *formal_parameters_p;
formal_parameters_p = ECMA_GET_POINTER (ecma_collection_header_t,
formal_parameters_prop_p->u.internal_property.value);
if (formal_parameters_p != NULL)
{
ecma_length_t formal_parameters_count = formal_parameters_p->unit_number;
ecma_collection_iterator_t formal_params_iterator;
ecma_collection_iterator_init (&formal_params_iterator, formal_parameters_p);
/*
* Formal parameter list is stored in reversed order
*
* Although, specification defines ascending order of formal parameters list enumeration,
* implementation enumerates the parameters in descending order.
*
* In the case, redundant SetMutableBinding invocation could be avoided.
*/
for (ssize_t n = (ssize_t) formal_parameters_count - 1;
n >= 0;
n--)
{
ecma_value_t v;
if (n >= (ssize_t) arguments_list_len)
{
v = ecma_make_simple_value (ECMA_SIMPLE_VALUE_UNDEFINED);
}
else
{
v = arguments_list_p[n];
}
bool is_moved = ecma_collection_iterator_next (&formal_params_iterator);
JERRY_ASSERT (is_moved);
ecma_value_t formal_parameter_name_value = *formal_params_iterator.current_value_p;
ecma_string_t *formal_parameter_name_string_p = ecma_get_string_from_value (formal_parameter_name_value);
bool arg_already_declared = ecma_op_has_binding (env_p, formal_parameter_name_string_p);
if (!arg_already_declared)
{
ecma_completion_value_t completion = ecma_op_create_mutable_binding (env_p,
formal_parameter_name_string_p,
false);
if (ecma_is_completion_value_throw (completion))
{
return completion;
}
JERRY_ASSERT (ecma_is_completion_value_empty (completion));
completion = ecma_op_set_mutable_binding (env_p,
formal_parameter_name_string_p,
v,
is_strict);
if (ecma_is_completion_value_throw (completion))
{
return completion;
}
JERRY_ASSERT (ecma_is_completion_value_empty (completion));
}
}
}
if (do_instantiate_arguments_object)
{
/*
* According to ECMA-262 v5, 10.5, the Arguments object should be instantiated
* after instantiating declared functions, and only if there is no binding named 'arguments'
* by that time.
*
* However, we can setup Arguments object and 'arguments' binding here, because:
* - instantiation of Arguments object itself doesn't have any side effects;
* - if 'arguments' is name of a declared function in current scope,
* value of the binding would be overwritten, execution would proceed in correct state.
* - declaration of function, named 'arguments', is considered to be unrecommended (and so, rare) case,
* so instantiation of Arguments object here, in general, is supposed to not affect resource consumption
* significantly.
*/
ecma_string_t *arguments_string_p = ecma_get_magic_string (LIT_MAGIC_STRING_ARGUMENTS);
bool binding_already_declared = ecma_op_has_binding (env_p, arguments_string_p);
if (!binding_already_declared)
{
ecma_object_t *args_obj_p = ecma_op_create_arguments_object (func_obj_p,
env_p,
formal_parameters_p,
arguments_list_p,
arguments_list_len,
is_strict);
if (is_strict)
{
ecma_op_create_immutable_binding (env_p, arguments_string_p);
ecma_op_initialize_immutable_binding (env_p, arguments_string_p, ecma_make_object_value (args_obj_p));
}
else
{
ecma_completion_value_t completion = ecma_op_create_mutable_binding (env_p,
arguments_string_p,
false);
JERRY_ASSERT (ecma_is_completion_value_empty (completion));
completion = ecma_op_set_mutable_binding (env_p,
arguments_string_p,
ecma_make_object_value (args_obj_p),
false);
JERRY_ASSERT (ecma_is_completion_value_empty (completion));
}
ecma_deref_object (args_obj_p);
}
ecma_deref_ecma_string (arguments_string_p);
}
return ecma_make_empty_completion_value ();
} /* ecma_function_call_setup_args_variables */