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Implement eval support for functions with arguments lexical env. (#3806)

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JerryScript-DCO-1.0-Signed-off-by: Zoltan Herczeg zherczeg.u-szeged@partner.samsung.com
This commit is contained in:
Zoltan Herczeg
2020-06-08 12:11:54 +02:00
committed by GitHub
parent fed1b0c827
commit 2058ea1286
11 changed files with 214 additions and 44 deletions
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jerry-core/ecma/base/ecma-globals.h
+8 -6
View File
@@ -110,15 +110,16 @@ typedef enum
ECMA_PARSE_MODULE = (1u << 1), /**< module is parsed */
ECMA_PARSE_EVAL = (1u << 2), /**< eval is called */
ECMA_PARSE_DIRECT_EVAL = (1u << 3), /**< eval is called directly (ECMA-262 v5, 15.1.2.1.1) */
ECMA_PARSE_CLASS_CONSTRUCTOR = (1u << 4), /**< a class constructor is being parsed */
/* These 4 status flags must be in this order. See PARSER_SAVED_FLAGS_OFFSET. */
ECMA_PARSE_CLASS_CONSTRUCTOR = (1u << 4), /**< a class constructor is being parsed (this value must be kept in
* in sync with PARSER_CLASS_CONSTRUCTOR) */
/* These four status flags must be in this order. The first three are also parser status flags.
* See PARSER_SAVE_STATUS_FLAGS / PARSER_RESTORE_STATUS_FLAGS. */
ECMA_PARSE_ALLOW_SUPER = (1u << 5), /**< allow super property access */
ECMA_PARSE_ALLOW_SUPER_CALL = (1u << 6), /**< allow super constructor call */
ECMA_PARSE_ALLOW_NEW_TARGET = (1u << 7), /**< allow new.target access */
ECMA_PARSE_FUNCTION_CONTEXT = (1u << 8), /**< function context is present (ECMA_PARSE_DIRECT_EVAL must be set) */
ECMA_PARSE_GENERATOR_FUNCTION = (1u << 8), /**< generator function is parsed */
ECMA_PARSE_GENERATOR_FUNCTION = (1u << 9), /**< generator function is parsed */
/* These flags are internally used by the parser. */
#ifndef JERRY_NDEBUG
@@ -126,7 +127,7 @@ typedef enum
* This flag represents an error in for in/of statements, which cannot be set
* if the parsing is completed successfully.
*/
ECMA_PARSE_INTERNAL_FOR_IN_OFF_CONTEXT_ERROR = (1u << 9),
ECMA_PARSE_INTERNAL_FOR_IN_OFF_CONTEXT_ERROR = (1u << 30),
#endif /* !JERRY_NDEBUG */
} ecma_parse_opts_t;
@@ -707,7 +708,8 @@ typedef enum
/**
* Get JERRY_CONTEXT (status_flags) top 8 bits.
*/
#define ECMA_GET_LOCAL_PARSE_OPTS() (JERRY_CONTEXT (status_flags) >> ECMA_LOCAL_PARSE_OPTS_OFFSET)
#define ECMA_GET_LOCAL_PARSE_OPTS() \
(JERRY_CONTEXT (status_flags) >> (ECMA_LOCAL_PARSE_OPTS_OFFSET - JERRY_LOG2 (ECMA_PARSE_ALLOW_SUPER)))
/**
* Clear JERRY_CONTEXT (status_flags) top 8 bits.
jerry-core/include/jerryscript-snapshot.h
+1 -1
View File
@@ -30,7 +30,7 @@ extern "C"
/**
* Jerry snapshot format version.
*/
#define JERRY_SNAPSHOT_VERSION (46u)
#define JERRY_SNAPSHOT_VERSION (47u)
/**
* Flags for jerry_generate_snapshot and jerry_generate_function_snapshot.
jerry-core/parser/js/byte-code.c
+1 -1
View File
@@ -27,7 +27,7 @@ JERRY_STATIC_ASSERT ((sizeof (cbc_uint16_arguments_t) % sizeof (jmem_cpointer_t)
*/
JERRY_STATIC_ASSERT (CBC_END == 238,
number_of_cbc_opcodes_changed);
JERRY_STATIC_ASSERT (CBC_EXT_END == 116,
JERRY_STATIC_ASSERT (CBC_EXT_END == 118,
number_of_cbc_ext_opcodes_changed);
#if ENABLED (JERRY_PARSER)
jerry-core/parser/js/byte-code.h
+4
View File
@@ -566,6 +566,10 @@
VM_OC_PUSH_LIT_POS_BYTE | VM_OC_GET_LITERAL) \
CBC_OPCODE (CBC_EXT_PUSH_LITERAL_PUSH_NUMBER_NEG_BYTE, CBC_HAS_LITERAL_ARG | CBC_HAS_BYTE_ARG, 2, \
VM_OC_PUSH_LIT_NEG_BYTE | VM_OC_GET_LITERAL) \
CBC_OPCODE (CBC_EXT_CREATE_VAR_EVAL, CBC_HAS_LITERAL_ARG, 0, \
VM_OC_EXT_VAR_EVAL) \
CBC_OPCODE (CBC_EXT_CREATE_VAR_FUNC_EVAL, CBC_HAS_LITERAL_ARG | CBC_HAS_LITERAL_ARG2, 0, \
VM_OC_EXT_VAR_EVAL) \
CBC_OPCODE (CBC_EXT_STRING_CONCAT, CBC_NO_FLAG, -1, \
VM_OC_STRING_CONCAT | VM_OC_GET_STACK_STACK | VM_OC_PUT_STACK) \
CBC_OPCODE (CBC_EXT_STRING_CONCAT_RIGHT_LITERAL, CBC_HAS_LITERAL_ARG, 0, \
jerry-core/parser/js/js-parser-expr.c
+12 -5
View File
@@ -2224,16 +2224,23 @@ parser_process_unary_expression (parser_context_t *context_p, /**< context */
context_p->status_flags |= PARSER_LEXICAL_ENV_NEEDED;
#if ENABLED (JERRY_ES2015)
uint16_t eval_flags = PARSER_SAVE_STATUS_FLAGS (context_p->status_flags);
const uint32_t required_flags = PARSER_IS_FUNCTION | PARSER_LEXICAL_BLOCK_NEEDED;
if (context_p->status_flags & PARSER_FUNCTION_IS_PARSING_ARGS)
{
context_p->status_flags |= PARSER_LEXICAL_BLOCK_NEEDED;
}
if (context_p->status_flags & (PARSER_ALLOW_SUPER_CALL | PARSER_ALLOW_SUPER | PARSER_ALLOW_NEW_TARGET))
else if (((context_p->status_flags & (required_flags | PARSER_IS_STRICT)) == required_flags)
|| ((context_p->global_status_flags & ECMA_PARSE_FUNCTION_CONTEXT)
&& !(context_p->status_flags & PARSER_IS_FUNCTION)))
{
parser_emit_cbc_ext_call (context_p,
CBC_EXT_LOCAL_EVAL,
PARSER_SAVE_STATUS_FLAGS (context_p->status_flags));
eval_flags |= PARSER_GET_EVAL_FLAG (ECMA_PARSE_FUNCTION_CONTEXT);
}
if (eval_flags != 0)
{
parser_emit_cbc_ext_call (context_p, CBC_EXT_LOCAL_EVAL, eval_flags);
}
else
{
jerry-core/parser/js/js-parser-internal.h
+31 -19
View File
@@ -67,9 +67,9 @@ typedef enum
PARSER_FUNCTION_IS_PARSING_ARGS = (1u << 17), /**< set when parsing function arguments */
PARSER_FUNCTION_HAS_NON_SIMPLE_PARAM = (1u << 18), /**< function has a non simple parameter */
PARSER_FUNCTION_HAS_REST_PARAM = (1u << 19), /**< function has rest parameter */
/* These 4 status flags must be in this order. See PARSER_SAVED_FLAGS_OFFSET. */
PARSER_CLASS_CONSTRUCTOR = (1u << 20), /**< a class constructor is parsed
* Note: PARSER_ALLOW_SUPER must be present */
/* These three status flags must be in this order. See PARSER_SAVED_FLAGS_OFFSET. */
PARSER_ALLOW_SUPER = (1u << 21), /**< allow super property access */
PARSER_ALLOW_SUPER_CALL = (1u << 22), /**< allow super constructor call
* Note: PARSER_CLASS_CONSTRUCTOR must be present */
@@ -154,34 +154,40 @@ typedef enum
#if ENABLED (JERRY_ES2015)
/**
* Offset between PARSER_CLASS_CONSTRUCTOR and ECMA_PARSE_CLASS_CONSTRUCTOR
* Offset of PARSER_ALLOW_SUPER
*/
#define PARSER_SAVED_FLAGS_OFFSET \
(JERRY_LOG2 (PARSER_CLASS_CONSTRUCTOR) - JERRY_LOG2 (ECMA_PARSE_CLASS_CONSTRUCTOR))
JERRY_LOG2 (PARSER_ALLOW_SUPER)
/**
* Count of ecma_parse_opts_t class parsing options related bits
* Mask of saved flags
*/
#define PARSER_SAVED_FLAGS_COUNT \
(JERRY_LOG2 (ECMA_PARSE_ALLOW_NEW_TARGET) - JERRY_LOG2 (ECMA_PARSE_CLASS_CONSTRUCTOR) + 1)
/**
* Mask for get class option bits from ecma_parse_opts_t
*/
#define PARSER_CLASS_ECMA_PARSE_OPTS_TO_PARSER_OPTS_MASK \
(((1 << PARSER_SAVED_FLAGS_COUNT) - 1) << JERRY_LOG2 (ECMA_PARSE_CLASS_CONSTRUCTOR))
/**
* Get class option bits from ecma_parse_opts_t
*/
#define PARSER_GET_SAVED_FLAGS(opts) \
(((opts) & PARSER_CLASS_ECMA_PARSE_OPTS_TO_PARSER_OPTS_MASK) << PARSER_SAVED_FLAGS_OFFSET)
#define PARSER_SAVED_FLAGS_MASK \
((1 << (JERRY_LOG2 (PARSER_ALLOW_NEW_TARGET) - JERRY_LOG2 (PARSER_ALLOW_SUPER) + 1)) - 1)
/**
* Get class option bits from parser_general_flags_t
*/
#define PARSER_SAVE_STATUS_FLAGS(opts) \
((uint16_t) (((opts) >> PARSER_SAVED_FLAGS_OFFSET) & PARSER_CLASS_ECMA_PARSE_OPTS_TO_PARSER_OPTS_MASK))
((uint16_t) (((opts) >> PARSER_SAVED_FLAGS_OFFSET) & PARSER_SAVED_FLAGS_MASK))
/**
* Mask for get class option bits from ecma_parse_opts_t
*/
#define PARSER_RESTORE_STATUS_FLAGS_MASK \
(((ECMA_PARSE_ALLOW_NEW_TARGET << 1) - 1) - (ECMA_PARSE_ALLOW_SUPER - 1))
/**
* Shift for get class option bits from ecma_parse_opts_t
*/
#define PARSER_RESTORE_STATUS_FLAGS_SHIFT \
(JERRY_LOG2 (PARSER_ALLOW_SUPER) - JERRY_LOG2 (ECMA_PARSE_ALLOW_SUPER))
/**
* Get class option bits from ecma_parse_opts_t
*/
#define PARSER_RESTORE_STATUS_FLAGS(opts) \
(((opts) & PARSER_RESTORE_STATUS_FLAGS_MASK) << PARSER_RESTORE_STATUS_FLAGS_SHIFT)
/**
* All flags that affect exotic arguments object creation.
@@ -189,6 +195,12 @@ typedef enum
#define PARSER_ARGUMENTS_RELATED_FLAGS \
(PARSER_ARGUMENTS_NEEDED | PARSER_FUNCTION_HAS_NON_SIMPLE_PARAM | PARSER_IS_STRICT)
/**
* Get the corresponding eval flag for a ecma_parse_opts_t flag
*/
#define PARSER_GET_EVAL_FLAG(type) \
((type) >> JERRY_LOG2 (ECMA_PARSE_ALLOW_SUPER))
#else /* !ENABLED (JERRY_ES2015) */
/**
jerry-core/parser/js/js-parser.c
+8 -3
View File
@@ -27,8 +27,13 @@ JERRY_STATIC_ASSERT ((int) ECMA_PARSE_STRICT_MODE == (int) PARSER_IS_STRICT,
ecma_parse_strict_mode_must_be_equal_to_parser_is_strict);
#if ENABLED (JERRY_ES2015)
JERRY_STATIC_ASSERT ((ECMA_PARSE_CLASS_CONSTRUCTOR << PARSER_SAVED_FLAGS_OFFSET) == PARSER_CLASS_CONSTRUCTOR,
ecma_saved_parse_options_must_be_transformed_to_ecma_general_flags);
JERRY_STATIC_ASSERT (PARSER_SAVE_STATUS_FLAGS (PARSER_ALLOW_SUPER) == 0x1,
incorrect_saving_of_ecma_parse_allow_super);
JERRY_STATIC_ASSERT (PARSER_RESTORE_STATUS_FLAGS (ECMA_PARSE_ALLOW_SUPER) == PARSER_ALLOW_SUPER,
incorrect_restoring_of_ecma_parse_allow_super);
JERRY_STATIC_ASSERT (PARSER_RESTORE_STATUS_FLAGS (ECMA_PARSE_FUNCTION_CONTEXT) == 0,
ecma_parse_function_context_must_not_be_transformed);
#endif /* ENABLED (JERRY_ES2015) */
/** \addtogroup parser Parser
@@ -2016,7 +2021,7 @@ parser_parse_source (const uint8_t *arg_list_p, /**< function argument list */
}
#if ENABLED (JERRY_ES2015)
context.status_flags |= PARSER_GET_SAVED_FLAGS (parse_opts);
context.status_flags |= PARSER_RESTORE_STATUS_FLAGS (parse_opts);
context.tagged_template_literal_cp = JMEM_CP_NULL;
#endif /* ENABLED (JERRY_ES2015) */
jerry-core/parser/js/js-scanner-util.c
+30 -5
View File
@@ -2227,9 +2227,9 @@ scanner_create_variables (parser_context_t *context_p, /**< context */
context_p->scope_stack_top = (uint16_t) (scope_stack_p - context_p->scope_stack_p);
#endif /* ENABLED (JERRY_PARSER_DUMP_BYTE_CODE) */
uint16_t opcode = ((option_flags & SCANNER_CREATE_VARS_IS_SCRIPT) ? CBC_CREATE_VAR_EVAL
: CBC_CREATE_VAR);
#if ENABLED (JERRY_ES2015)
uint16_t opcode;
switch (type)
{
case SCANNER_STREAM_TYPE_LET:
@@ -2242,14 +2242,34 @@ scanner_create_variables (parser_context_t *context_p, /**< context */
opcode = CBC_CREATE_CONST;
break;
}
case SCANNER_STREAM_TYPE_LOCAL:
case SCANNER_STREAM_TYPE_DESTRUCTURED_ARG:
case SCANNER_STREAM_TYPE_DESTRUCTURED_ARG_FUNC:
case SCANNER_STREAM_TYPE_VAR:
{
opcode = CBC_CREATE_VAR;
if (option_flags & SCANNER_CREATE_VARS_IS_SCRIPT)
{
opcode = CBC_CREATE_VAR_EVAL;
if (context_p->global_status_flags & ECMA_PARSE_FUNCTION_CONTEXT)
{
opcode = PARSER_TO_EXT_OPCODE (CBC_EXT_CREATE_VAR_EVAL);
}
}
break;
}
default:
{
JERRY_ASSERT (type == SCANNER_STREAM_TYPE_LOCAL
|| type == SCANNER_STREAM_TYPE_DESTRUCTURED_ARG
|| type == SCANNER_STREAM_TYPE_DESTRUCTURED_ARG_FUNC);
opcode = CBC_CREATE_LOCAL;
break;
}
}
#else /* !ENABLED (JERRY_ES2015) */
uint16_t opcode = ((option_flags & SCANNER_CREATE_VARS_IS_SCRIPT) ? CBC_CREATE_VAR_EVAL
: CBC_CREATE_VAR);
#endif /* ENABLED (JERRY_ES2015) */
parser_emit_cbc_literal (context_p, opcode, map_to);
@@ -2323,6 +2343,11 @@ scanner_create_variables (parser_context_t *context_p, /**< context */
|| !scanner_scope_find_let_declaration (context_p, &literal))
{
func_init_opcode = CBC_CREATE_VAR_FUNC_EVAL;
if (context_p->global_status_flags & ECMA_PARSE_FUNCTION_CONTEXT)
{
func_init_opcode = PARSER_TO_EXT_OPCODE (CBC_EXT_CREATE_VAR_FUNC_EVAL);
}
}
literal.char_p += data_p[1];
#else /* !ENABLED (JERRY_ES2015) */
jerry-core/vm/vm.c
+68 -4
View File
@@ -1322,39 +1322,41 @@ vm_loop (vm_frame_ctx_t *frame_ctx_p) /**< frame context */
{
uint32_t value_index;
READ_LITERAL_INDEX (value_index);
JERRY_ASSERT (value_index >= const_literal_end);
lit_value = vm_construct_literal_object (frame_ctx_p,
literal_start_p[value_index]);
}
READ_LITERAL_INDEX (literal_index);
JERRY_ASSERT (literal_index >= register_end);
ecma_string_t *name_p = ecma_get_string_from_value (literal_start_p[literal_index]);
ecma_object_t *lex_env_p = frame_ctx_p->lex_env_p;
while (lex_env_p->type_flags_refs & ECMA_OBJECT_FLAG_BLOCK)
{
#if ENABLED (JERRY_ES2015) && !(defined JERRY_NDEBUG)
#if ENABLED (JERRY_ES2015) && !(defined JERRY_NDEBUG)
if (ecma_get_lex_env_type (lex_env_p) == ECMA_LEXICAL_ENVIRONMENT_DECLARATIVE)
{
ecma_property_t *property_p = ecma_find_named_property (lex_env_p, name_p);
JERRY_ASSERT (property_p == NULL || !(*property_p & ECMA_PROPERTY_FLAG_ENUMERABLE));
}
#endif /* ENABLED (JERRY_ES2015) && !JERRY_NDEBUG */
#endif /* ENABLED (JERRY_ES2015) && !JERRY_NDEBUG */
JERRY_ASSERT (lex_env_p->u2.outer_reference_cp != JMEM_CP_NULL);
lex_env_p = ECMA_GET_NON_NULL_POINTER (ecma_object_t, lex_env_p->u2.outer_reference_cp);
}
#if ENABLED (JERRY_ES2015) && !(defined JERRY_NDEBUG)
#if ENABLED (JERRY_ES2015) && !(defined JERRY_NDEBUG)
if (ecma_get_lex_env_type (lex_env_p) == ECMA_LEXICAL_ENVIRONMENT_DECLARATIVE)
{
ecma_property_t *property_p = ecma_find_named_property (lex_env_p, name_p);
JERRY_ASSERT (property_p == NULL || !(*property_p & ECMA_PROPERTY_FLAG_ENUMERABLE));
}
#endif /* ENABLED (JERRY_ES2015) && !JERRY_NDEBUG */
#endif /* ENABLED (JERRY_ES2015) && !JERRY_NDEBUG */
result = vm_var_decl (lex_env_p, name_p, frame_ctx_p->is_eval_code);
@@ -1375,6 +1377,68 @@ vm_loop (vm_frame_ctx_t *frame_ctx_p) /**< frame context */
continue;
}
#if ENABLED (JERRY_ES2015)
case VM_OC_EXT_VAR_EVAL:
{
uint32_t literal_index;
ecma_value_t lit_value = ECMA_VALUE_UNDEFINED;
JERRY_ASSERT (byte_code_start_p[0] == CBC_EXT_OPCODE);
if (opcode == CBC_EXT_CREATE_VAR_FUNC_EVAL)
{
uint32_t value_index;
READ_LITERAL_INDEX (value_index);
JERRY_ASSERT (value_index >= const_literal_end);
lit_value = vm_construct_literal_object (frame_ctx_p,
literal_start_p[value_index]);
}
READ_LITERAL_INDEX (literal_index);
JERRY_ASSERT (literal_index >= register_end);
ecma_string_t *name_p = ecma_get_string_from_value (literal_start_p[literal_index]);
ecma_object_t *lex_env_p = frame_ctx_p->lex_env_p;
ecma_object_t *prev_lex_env_p = NULL;
while (lex_env_p->type_flags_refs & ECMA_OBJECT_FLAG_BLOCK)
{
#if !(defined JERRY_NDEBUG)
if (ecma_get_lex_env_type (lex_env_p) == ECMA_LEXICAL_ENVIRONMENT_DECLARATIVE)
{
ecma_property_t *property_p = ecma_find_named_property (lex_env_p, name_p);
JERRY_ASSERT (property_p == NULL || !(*property_p & ECMA_PROPERTY_FLAG_ENUMERABLE));
}
#endif /* !JERRY_NDEBUG */
JERRY_ASSERT (lex_env_p->u2.outer_reference_cp != JMEM_CP_NULL);
prev_lex_env_p = lex_env_p;
lex_env_p = ECMA_GET_NON_NULL_POINTER (ecma_object_t, lex_env_p->u2.outer_reference_cp);
}
JERRY_ASSERT (ecma_get_lex_env_type (lex_env_p) == ECMA_LEXICAL_ENVIRONMENT_DECLARATIVE);
JERRY_ASSERT (prev_lex_env_p != NULL
&& ecma_get_lex_env_type (prev_lex_env_p) == ECMA_LEXICAL_ENVIRONMENT_DECLARATIVE);
JERRY_ASSERT (ecma_find_named_property (prev_lex_env_p, name_p) == NULL);
ecma_property_value_t *property_value_p;
property_value_p = ecma_create_named_data_property (prev_lex_env_p,
name_p,
ECMA_PROPERTY_CONFIGURABLE_WRITABLE,
NULL);
if (lit_value == ECMA_VALUE_UNDEFINED)
{
continue;
}
property_value_p->value = lit_value;
ecma_deref_object (ecma_get_object_from_value (lit_value));
continue;
}
#endif /* ENABLED (JERRY_ES2015) */
#if ENABLED (JERRY_SNAPSHOT_EXEC)
case VM_OC_SET_BYTECODE_PTR:
{
jerry-core/vm/vm.h
+6
View File
@@ -219,6 +219,10 @@ typedef enum
VM_OC_CREATE_BINDING, /**< create variables */
VM_OC_SET_BYTECODE_PTR, /**< setting bytecode pointer */
VM_OC_VAR_EVAL, /**< variable and function evaluation */
#if ENABLED (JERRY_ES2015)
VM_OC_EXT_VAR_EVAL, /**< variable and function evaluation for
* functions with separate argument context */
#endif /* ENABLED (JERRY_ES2015) */
VM_OC_INIT_ARG_OR_FUNC, /**< create and init a function or argument binding */
#if ENABLED (JERRY_DEBUGGER)
@@ -298,6 +302,8 @@ typedef enum
VM_OC_LINE = VM_OC_NONE, /**< line number of the next statement is unused */
#endif /* !ENABLED (JERRY_LINE_INFO) */
#if !ENABLED (JERRY_ES2015)
VM_OC_EXT_VAR_EVAL = VM_OC_NONE, /**< variable and function evaluation for
* functions with separate argument context */
VM_OC_CHECK_VAR = VM_OC_NONE, /**< check redeclared vars in the global scope */
VM_OC_CHECK_LET = VM_OC_NONE, /**< check redeclared lets in the global scope */
VM_OC_ASSIGN_LET_CONST = VM_OC_NONE, /**< assign values to let/const declarations */
tests/jerry/es2015/function-scope2.js
+45
View File
@@ -0,0 +1,45 @@
// Copyright JS Foundation and other contributors, http://js.foundation
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
var a = 1;
var b = 2;
function f(x = eval("eval('var a = 3; function b() { return 4 } () => a')"), y = b) {
eval("eval('var a = 5; function b() { return 6 }')");
assert(a === 5);
assert(b() === 6);
assert(x() === 3);
assert(y() === 4);
delete a;
delete b;
assert(a === 3);
assert(b() === 4);
assert(x() === 3);
assert(y() === 4);
delete a;
delete b;
assert(a === 1);
assert(b === 2);
assert(x() === 1);
assert(y() === 4);
}
f()