cosmopolitan/third_party/quickjs/parse.c

/*
 * QuickJS Javascript Engine
 *
 * Copyright (c) 2017-2021 Fabrice Bellard
 * Copyright (c) 2017-2021 Charlie Gordon
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */
#include "libc/assert.h"
#include "libc/fmt/fmt.h"
#include "libc/runtime/runtime.h"
#include "libc/str/str.h"
#include "third_party/quickjs/internal.h"
#include "third_party/quickjs/libregexp.h"

asm(".ident\t\"\\n\\n\
QuickJS (MIT License)\\n\
Copyright (c) 2017-2021 Fabrice Bellard\\n\
Copyright (c) 2017-2021 Charlie Gordon\"");
asm(".include \"libc/disclaimer.inc\"");
/* clang-format off */

static __exception int js_parse_assign_expr(JSParseState *);
static __exception int js_parse_assign_expr2(JSParseState *, int);
static __exception int js_parse_expr(JSParseState *);
static __exception int js_parse_function_decl(JSParseState *, JSParseFunctionEnum, JSFunctionKindEnum, JSAtom, const uint8_t *, int);
static __exception int js_parse_function_decl2(JSParseState *, JSParseFunctionEnum, JSFunctionKindEnum, JSAtom, const uint8_t *, int, JSParseExportEnum, JSFunctionDef **);
static __exception int js_parse_postfix_expr(JSParseState *, int);
static __exception int js_parse_unary(JSParseState *, int);

void js_parse_init(JSContext *ctx, JSParseState *s,
                   const char *input, size_t input_len,
                   const char *filename)
{
    bzero(s, sizeof(*s));
    s->ctx = ctx;
    s->filename = filename;
    s->line_num = 1;
    s->buf_ptr = (const uint8_t *)input;
    s->buf_end = s->buf_ptr + input_len;
    s->token.val = ' ';
    s->token.line_num = 1;
}

/* Note: all the fields are already sealed except length */
static int seal_template_obj(JSContext *ctx, JSValueConst obj)
{
    JSObject *p;
    JSShapeProperty *prs;
    p = JS_VALUE_GET_OBJ(obj);
    prs = find_own_property1(p, JS_ATOM_length);
    if (prs) {
        if (js_update_property_flags(ctx, p, &prs,
                                     prs->flags & ~(JS_PROP_CONFIGURABLE | JS_PROP_WRITABLE)))
            return -1;
    }
    p->extensible = FALSE;
    return 0;
}

static __exception int emit_push_const(JSParseState *s, JSValueConst val,
                                       BOOL as_atom)
{
    int idx;
    if (JS_VALUE_GET_TAG(val) == JS_TAG_STRING && as_atom) {
        JSAtom atom;
        /* warning: JS_NewAtomStr frees the string value */
        JS_DupValue(s->ctx, val);
        atom = JS_NewAtomStr(s->ctx, JS_VALUE_GET_STRING(val));
        if (atom != JS_ATOM_NULL && !__JS_AtomIsTaggedInt(atom)) {
            emit_op(s, OP_push_atom_value);
            emit_u32(s, atom);
            return 0;
        }
    }
    idx = cpool_add(s, JS_DupValue(s->ctx, val));
    if (idx < 0)
        return -1;
    emit_op(s, OP_push_const);
    emit_u32(s, idx);
    return 0;
}

int js_parse_template_part(JSParseState *s, const uint8_t *p)
{
    uint32_t c;
    StringBuffer b_s, *b = &b_s;
    /* p points to the first byte of the template part */
    if (string_buffer_init(s->ctx, b, 32))
        goto fail;
    for(;;) {
        if (p >= s->buf_end)
            goto unexpected_eof;
        c = *p++;
        if (c == '`') {
            /* template end part */
            break;
        }
        if (c == '$' && *p == '{') {
            /* template start or middle part */
            p++;
            break;
        }
        if (c == '\\') {
            if (string_buffer_putc8(b, c))
                goto fail;
            if (p >= s->buf_end)
                goto unexpected_eof;
            c = *p++;
        }
        /* newline sequences are normalized as single '\n' bytes */
        if (c == '\r') {
            if (*p == '\n')
                p++;
            c = '\n';
        }
        if (c == '\n') {
            s->line_num++;
        } else if (c >= 0x80) {
            const uint8_t *p_next;
            c = unicode_from_utf8(p - 1, UTF8_CHAR_LEN_MAX, &p_next);
            if (c > 0x10FFFF) {
                js_parse_error(s, "invalid UTF-8 sequence");
                goto fail;
            }
            p = p_next;
        }
        if (string_buffer_putc(b, c))
            goto fail;
    }
    s->token.val = TOK_TEMPLATE;
    s->token.u.str.sep = c;
    s->token.u.str.str = string_buffer_end(b);
    s->buf_ptr = p;
    return 0;
 unexpected_eof:
    js_parse_error(s, "unexpected end of string");
 fail:
    string_buffer_free(b);
    return -1;
}

int js_parse_string(JSParseState *s, int sep,
                    BOOL do_throw, const uint8_t *p,
                    JSToken *token, const uint8_t **pp)
{
    int ret;
    uint32_t c;
    StringBuffer b_s, *b = &b_s;
    /* string */
    if (string_buffer_init(s->ctx, b, 32))
        goto fail;
    for(;;) {
        if (p >= s->buf_end)
            goto invalid_char;
        c = *p;
        if (c < 0x20) {
            if (!s->cur_func) {
                if (do_throw)
                    js_parse_error(s, "invalid character in a JSON string");
                goto fail;
            }
            if (sep == '`') {
                if (c == '\r') {
                    if (p[1] == '\n')
                        p++;
                    c = '\n';
                }
                /* do not update s->line_num */
            } else if (c == '\n' || c == '\r')
                goto invalid_char;
        }
        p++;
        if (c == sep)
            break;
        if (c == '$' && *p == '{' && sep == '`') {
            /* template start or middle part */
            p++;
            break;
        }
        if (c == '\\') {
            c = *p;
            /* XXX: need a specific JSON case to avoid
               accepting invalid escapes */
            switch(c) {
            case '\0':
                if (p >= s->buf_end)
                    goto invalid_char;
                p++;
                break;
            case '\'':
            case '\"':
            case '\\':
                p++;
                break;
            case '\r':  /* accept DOS and MAC newline sequences */
                if (p[1] == '\n') {
                    p++;
                }
                /* fall thru */
            case '\n':
                /* ignore escaped newline sequence */
                p++;
                if (sep != '`')
                    s->line_num++;
                continue;
            default:
                if (c >= '0' && c <= '9') {
                    if (!s->cur_func)
                        goto invalid_escape; /* JSON case */
                    if (!(s->cur_func->js_mode & JS_MODE_STRICT) && sep != '`')
                        goto parse_escape;
                    if (c == '0' && !(p[1] >= '0' && p[1] <= '9')) {
                        p++;
                        c = '\0';
                    } else {
                        if (c >= '8' || sep == '`') {
                            /* Note: according to ES2021, \8 and \9 are not
                               accepted in strict mode or in templates. */
                            goto invalid_escape;
                        } else {
                            if (do_throw)
                                js_parse_error(s, "octal escape sequences are not allowed in strict mode");
                        }
                        goto fail;
                    }
                } else if (c >= 0x80) {
                    const uint8_t *p_next;
                    c = unicode_from_utf8(p, UTF8_CHAR_LEN_MAX, &p_next);
                    if (c > 0x10FFFF) {
                        goto invalid_utf8;
                    }
                    p = p_next;
                    /* LS or PS are skipped */
                    if (c == CP_LS || c == CP_PS)
                        continue;
                } else {
                parse_escape:
                    ret = lre_parse_escape(&p, TRUE);
                    if (ret == -1) {
                    invalid_escape:
                        if (do_throw)
                            js_parse_error(s, "malformed escape sequence in string literal");
                        goto fail;
                    } else if (ret < 0) {
                        /* ignore the '\' (could output a warning) */
                        p++;
                    } else {
                        c = ret;
                    }
                }
                break;
            }
        } else if (c >= 0x80) {
            const uint8_t *p_next;
            c = unicode_from_utf8(p - 1, UTF8_CHAR_LEN_MAX, &p_next);
            if (c > 0x10FFFF)
                goto invalid_utf8;
            p = p_next;
        }
        if (string_buffer_putc(b, c))
            goto fail;
    }
    token->val = TOK_STRING;
    token->u.str.sep = c;
    token->u.str.str = string_buffer_end(b);
    *pp = p;
    return 0;
 invalid_utf8:
    if (do_throw)
        js_parse_error(s, "invalid UTF-8 sequence");
    goto fail;
 invalid_char:
    if (do_throw)
        js_parse_error(s, "unexpected end of string");
 fail:
    string_buffer_free(b);
    return -1;
}

int js_parse_expect(JSParseState *s, int tok)
{
    if (s->token.val != tok) {
        /* XXX: dump token correctly in all cases */
        return js_parse_error(s, "expecting '%c'", tok);
    }
    return next_token(s);
}

static int js_parse_expect_semi(JSParseState *s)
{
    if (s->token.val != ';') {
        /* automatic insertion of ';' */
        if (s->token.val == TOK_EOF || s->token.val == '}' || s->got_lf) {
            return 0;
        }
        return js_parse_error(s, "expecting '%c'", ';');
    }
    return next_token(s);
}

static __exception int js_parse_statement_or_decl(JSParseState *s,
                                                  int decl_mask);

static __exception int js_parse_statement(JSParseState *s)
{
    return js_parse_statement_or_decl(s, 0);
}

static int get_first_lexical_var(JSFunctionDef *fd, int scope)
{
    while (scope >= 0) {
        int scope_idx = fd->scopes[scope].first;
        if (scope_idx >= 0)
            return scope_idx;
        scope = fd->scopes[scope].parent;
    }
    return -1;
}

static void pop_scope(JSParseState *s) {
    if (s->cur_func) {
        /* disable scoped variables */
        JSFunctionDef *fd = s->cur_func;
        int scope = fd->scope_level;
        emit_op(s, OP_leave_scope);
        emit_u16(s, scope);
        fd->scope_level = fd->scopes[scope].parent;
        fd->scope_first = get_first_lexical_var(fd, fd->scope_level);
    }
}

static __exception int js_parse_block(JSParseState *s)
{
    if (js_parse_expect(s, '{'))
        return -1;
    if (s->token.val != '}') {
        push_scope(s);
        for(;;) {
            if (js_parse_statement_or_decl(s, DECL_MASK_ALL))
                return -1;
            if (s->token.val == '}')
                break;
        }
        pop_scope(s);
    }
    if (next_token(s))
        return -1;
    return 0;
}

static __exception int js_parse_template(JSParseState *s, int call, int *argc)
{
    JSContext *ctx = s->ctx;
    JSValue raw_array, template_object;
    JSToken cooked;
    int depth, ret;
    raw_array = JS_UNDEFINED; /* avoid warning */
    template_object = JS_UNDEFINED; /* avoid warning */
    if (call) {
        /* Create a template object: an array of cooked strings */
        /* Create an array of raw strings and store it to the raw property */
        template_object = JS_NewArray(ctx);
        if (JS_IsException(template_object))
            return -1;
        //        pool_idx = s->cur_func->cpool_count;
        ret = emit_push_const(s, template_object, 0);
        JS_FreeValue(ctx, template_object);
        if (ret)
            return -1;
        raw_array = JS_NewArray(ctx);
        if (JS_IsException(raw_array))
            return -1;
        if (JS_DefinePropertyValue(ctx, template_object, JS_ATOM_raw,
                                   raw_array, JS_PROP_THROW) < 0) {
            return -1;
        }
    }
    depth = 0;
    while (s->token.val == TOK_TEMPLATE) {
        const uint8_t *p = s->token.ptr + 1;
        cooked = s->token;
        if (call) {
            if (JS_DefinePropertyValueUint32(ctx, raw_array, depth,
                                             JS_DupValue(ctx, s->token.u.str.str),
                                             JS_PROP_ENUMERABLE | JS_PROP_THROW) < 0) {
                return -1;
            }
            /* re-parse the string with escape sequences but do not throw a
               syntax error if it contains invalid sequences
             */
            if (js_parse_string(s, '`', FALSE, p, &cooked, &p)) {
                cooked.u.str.str = JS_UNDEFINED;
            }
            if (JS_DefinePropertyValueUint32(ctx, template_object, depth,
                                             cooked.u.str.str,
                                             JS_PROP_ENUMERABLE | JS_PROP_THROW) < 0) {
                return -1;
            }
        } else {
            JSString *str;
            /* re-parse the string with escape sequences and throw a
               syntax error if it contains invalid sequences
             */
            JS_FreeValue(ctx, s->token.u.str.str);
            s->token.u.str.str = JS_UNDEFINED;
            if (js_parse_string(s, '`', TRUE, p, &cooked, &p))
                return -1;
            str = JS_VALUE_GET_STRING(cooked.u.str.str);
            if (str->len != 0 || depth == 0) {
                ret = emit_push_const(s, cooked.u.str.str, 1);
                JS_FreeValue(s->ctx, cooked.u.str.str);
                if (ret)
                    return -1;
                if (depth == 0) {
                    if (s->token.u.str.sep == '`')
                        goto done1;
                    emit_op(s, OP_get_field2);
                    emit_atom(s, JS_ATOM_concat);
                }
                depth++;
            } else {
                JS_FreeValue(s->ctx, cooked.u.str.str);
            }
        }
        if (s->token.u.str.sep == '`')
            goto done;
        if (next_token(s))
            return -1;
        if (js_parse_expr(s))
            return -1;
        depth++;
        if (s->token.val != '}') {
            return js_parse_error(s, "expected '}' after template expression");
        }
        /* XXX: should convert to string at this stage? */
        free_token(s, &s->token);
        /* Resume TOK_TEMPLATE parsing (s->token.line_num and
         * s->token.ptr are OK) */
        s->got_lf = FALSE;
        s->last_line_num = s->token.line_num;
        if (js_parse_template_part(s, s->buf_ptr))
            return -1;
    }
    return js_parse_expect(s, TOK_TEMPLATE);
 done:
    if (call) {
        /* Seal the objects */
        seal_template_obj(ctx, raw_array);
        seal_template_obj(ctx, template_object);
        *argc = depth + 1;
    } else {
        emit_op(s, OP_call_method);
        emit_u16(s, depth - 1);
    }
 done1:
    return next_token(s);
}

static inline BOOL token_is_pseudo_keyword(JSParseState *s, JSAtom atom) {
    return s->token.val == TOK_IDENT && s->token.u.ident.atom == atom &&
        !s->token.u.ident.has_escape;
}

static int js_parse_get_pos(JSParseState *s, JSParsePos *sp)
{
    sp->last_line_num = s->last_line_num;
    sp->line_num = s->token.line_num;
    sp->ptr = s->token.ptr;
    sp->got_lf = s->got_lf;
    return 0;
}

static __exception int js_parse_seek_token(JSParseState *s, const JSParsePos *sp)
{
    s->token.line_num = sp->last_line_num;
    s->line_num = sp->line_num;
    s->buf_ptr = sp->ptr;
    s->got_lf = sp->got_lf;
    return next_token(s);
}

/* test if the current token is a let keyword. Use simplistic look-ahead scanner */
static int is_let(JSParseState *s, int decl_mask)
{
    int res = FALSE;
    if (token_is_pseudo_keyword(s, JS_ATOM_let)) {
#if 1
        JSParsePos pos;
        js_parse_get_pos(s, &pos);
        for (;;) {
            if (next_token(s)) {
                res = -1;
                break;
            }
            if (s->token.val == '[') {
                /* let [ is a syntax restriction:
                   it never introduces an ExpressionStatement */
                res = TRUE;
                break;
            }
            if (s->token.val == '{' ||
                (s->token.val == TOK_IDENT && !s->token.u.ident.is_reserved) ||
                s->token.val == TOK_LET ||
                s->token.val == TOK_YIELD ||
                s->token.val == TOK_AWAIT) {
                /* Check for possible ASI if not scanning for Declaration */
                /* XXX: should also check that `{` introduces a BindingPattern,
                   but Firefox does not and rejects eval("let=1;let\n{if(1)2;}") */
                if (s->last_line_num == s->token.line_num || (decl_mask & DECL_MASK_OTHER)) {
                    res = TRUE;
                    break;
                }
                break;
            }
            break;
        }
        if (js_parse_seek_token(s, &pos)) {
            res = -1;
        }
#else
        int tok = peek_token(s, TRUE);
        if (tok == '{' || tok == TOK_IDENT || peek_token(s, FALSE) == '[') {
            res = TRUE;
        }
#endif
    }
    return res;
}

static int peek_token(JSParseState *s, BOOL no_line_terminator)
{
    const uint8_t *p = s->buf_ptr;
    return simple_next_token(&p, no_line_terminator);
}

/* test if the current token is a label. Use simplistic look-ahead scanner */
static BOOL is_label(JSParseState *s)
{
    return (s->token.val == TOK_IDENT && !s->token.u.ident.is_reserved &&
            peek_token(s, FALSE) == ':');
}

static BOOL token_is_ident(int tok)
{
    /* Accept keywords and reserved words as property names */
    return (tok == TOK_IDENT ||
            (tok >= TOK_FIRST_KEYWORD &&
             tok <= TOK_LAST_KEYWORD));
}

/* if the property is an expression, name = JS_ATOM_NULL */
static int __exception js_parse_property_name(JSParseState *s,
                                              JSAtom *pname,
                                              BOOL allow_method, BOOL allow_var,
                                              BOOL allow_private)
{
    int is_private = 0;
    BOOL is_non_reserved_ident;
    JSAtom name;
    int prop_type;
    prop_type = PROP_TYPE_IDENT;
    if (allow_method) {
        if (token_is_pseudo_keyword(s, JS_ATOM_get)
        ||  token_is_pseudo_keyword(s, JS_ATOM_set)) {
            /* get x(), set x() */
            name = JS_DupAtom(s->ctx, s->token.u.ident.atom);
            if (next_token(s))
                goto fail1;
            if (s->token.val == ':' || s->token.val == ',' ||
                s->token.val == '}' || s->token.val == '(') {
                is_non_reserved_ident = TRUE;
                goto ident_found;
            }
            prop_type = PROP_TYPE_GET + (name == JS_ATOM_set);
            JS_FreeAtom(s->ctx, name);
        } else if (s->token.val == '*') {
            if (next_token(s))
                goto fail;
            prop_type = PROP_TYPE_STAR;
        } else if (token_is_pseudo_keyword(s, JS_ATOM_async) &&
                   peek_token(s, TRUE) != '\n') {
            name = JS_DupAtom(s->ctx, s->token.u.ident.atom);
            if (next_token(s))
                goto fail1;
            if (s->token.val == ':' || s->token.val == ',' ||
                s->token.val == '}' || s->token.val == '(') {
                is_non_reserved_ident = TRUE;
                goto ident_found;
            }
            JS_FreeAtom(s->ctx, name);
            if (s->token.val == '*') {
                if (next_token(s))
                    goto fail;
                prop_type = PROP_TYPE_ASYNC_STAR;
            } else {
                prop_type = PROP_TYPE_ASYNC;
            }
        }
    }
    if (token_is_ident(s->token.val)) {
        /* variable can only be a non-reserved identifier */
        is_non_reserved_ident =
            (s->token.val == TOK_IDENT && !s->token.u.ident.is_reserved);
        /* keywords and reserved words have a valid atom */
        name = JS_DupAtom(s->ctx, s->token.u.ident.atom);
        if (next_token(s))
            goto fail1;
    ident_found:
        if (is_non_reserved_ident &&
            prop_type == PROP_TYPE_IDENT && allow_var) {
            if (!(s->token.val == ':' ||
                  (s->token.val == '(' && allow_method))) {
                prop_type = PROP_TYPE_VAR;
            }
        }
    } else if (s->token.val == TOK_STRING) {
        name = JS_ValueToAtom(s->ctx, s->token.u.str.str);
        if (name == JS_ATOM_NULL)
            goto fail;
        if (next_token(s))
            goto fail1;
    } else if (s->token.val == TOK_NUMBER) {
        JSValue val;
        val = s->token.u.num.val;
#ifdef CONFIG_BIGNUM
        if (JS_VALUE_GET_TAG(val) == JS_TAG_BIG_FLOAT) {
            JSBigFloat *p = JS_VALUE_GET_PTR(val);
            val = s->ctx->rt->bigfloat_ops.
                mul_pow10_to_float64(s->ctx, &p->num,
                                     s->token.u.num.exponent);
            if (JS_IsException(val))
                goto fail;
            name = JS_ValueToAtom(s->ctx, val);
            JS_FreeValue(s->ctx, val);
        } else
#endif
        {
            name = JS_ValueToAtom(s->ctx, val);
        }
        if (name == JS_ATOM_NULL)
            goto fail;
        if (next_token(s))
            goto fail1;
    } else if (s->token.val == '[') {
        if (next_token(s))
            goto fail;
        if (js_parse_expr(s))
            goto fail;
        if (js_parse_expect(s, ']'))
            goto fail;
        name = JS_ATOM_NULL;
    } else if (s->token.val == TOK_PRIVATE_NAME && allow_private) {
        name = JS_DupAtom(s->ctx, s->token.u.ident.atom);
        if (next_token(s))
            goto fail1;
        is_private = PROP_TYPE_PRIVATE;
    } else {
        goto invalid_prop;
    }
    if (prop_type != PROP_TYPE_IDENT && prop_type != PROP_TYPE_VAR &&
        s->token.val != '(') {
        JS_FreeAtom(s->ctx, name);
    invalid_prop:
        js_parse_error(s, "invalid property name");
        goto fail;
    }
    *pname = name;
    return prop_type | is_private;
 fail1:
    JS_FreeAtom(s->ctx, name);
 fail:
    *pname = JS_ATOM_NULL;
    return -1;
}

static void set_object_name_computed(JSParseState *s)
{
    JSFunctionDef *fd = s->cur_func;
    int opcode;
    opcode = get_prev_opcode(fd);
    if (opcode == OP_set_name) {
        /* XXX: should free atom after OP_set_name? */
        fd->byte_code.size = fd->last_opcode_pos;
        fd->last_opcode_pos = -1;
        emit_op(s, OP_set_name_computed);
    } else if (opcode == OP_set_class_name) {
        int define_class_pos;
        define_class_pos = fd->last_opcode_pos + 1 -
            get_u32(fd->byte_code.buf + fd->last_opcode_pos + 1);
        assert(fd->byte_code.buf[define_class_pos] == OP_define_class);
        fd->byte_code.buf[define_class_pos] = OP_define_class_computed;
        fd->last_opcode_pos = -1;
    }
}

static void set_object_name(JSParseState *s, JSAtom name)
{
    JSFunctionDef *fd = s->cur_func;
    int opcode;
    opcode = get_prev_opcode(fd);
    if (opcode == OP_set_name) {
        /* XXX: should free atom after OP_set_name? */
        fd->byte_code.size = fd->last_opcode_pos;
        fd->last_opcode_pos = -1;
        emit_op(s, OP_set_name);
        emit_atom(s, name);
    } else if (opcode == OP_set_class_name) {
        int define_class_pos;
        JSAtom atom;
        define_class_pos = fd->last_opcode_pos + 1 -
            get_u32(fd->byte_code.buf + fd->last_opcode_pos + 1);
        assert(fd->byte_code.buf[define_class_pos] == OP_define_class);
        /* for consistency we free the previous atom which is
           JS_ATOM_empty_string */
        atom = get_u32(fd->byte_code.buf + define_class_pos + 1);
        JS_FreeAtom(s->ctx, atom);
        put_u32(fd->byte_code.buf + define_class_pos + 1,
                JS_DupAtom(s->ctx, name));
        fd->last_opcode_pos = -1;
    }
}

static __exception int js_parse_object_literal(JSParseState *s)
{
    JSAtom name = JS_ATOM_NULL;
    const uint8_t *start_ptr;
    int start_line, prop_type;
    BOOL has_proto;
    if (next_token(s))
        goto fail;
    /* XXX: add an initial length that will be patched back */
    emit_op(s, OP_object);
    has_proto = FALSE;
    while (s->token.val != '}') {
        /* specific case for getter/setter */
        start_ptr = s->token.ptr;
        start_line = s->token.line_num;
        if (s->token.val == TOK_ELLIPSIS) {
            if (next_token(s))
                return -1;
            if (js_parse_assign_expr(s))
                return -1;
            emit_op(s, OP_null);  /* dummy excludeList */
            emit_op(s, OP_copy_data_properties);
            emit_u8(s, 2 | (1 << 2) | (0 << 5));
            emit_op(s, OP_drop); /* pop excludeList */
            emit_op(s, OP_drop); /* pop src object */
            goto next;
        }
        prop_type = js_parse_property_name(s, &name, TRUE, TRUE, FALSE);
        if (prop_type < 0)
            goto fail;
        if (prop_type == PROP_TYPE_VAR) {
            /* shortcut for x: x */
            emit_op(s, OP_scope_get_var);
            emit_atom(s, name);
            emit_u16(s, s->cur_func->scope_level);
            emit_op(s, OP_define_field);
            emit_atom(s, name);
        } else if (s->token.val == '(') {
            BOOL is_getset = (prop_type == PROP_TYPE_GET ||
                              prop_type == PROP_TYPE_SET);
            JSParseFunctionEnum func_type;
            JSFunctionKindEnum func_kind;
            int op_flags;
            func_kind = JS_FUNC_NORMAL;
            if (is_getset) {
                func_type = JS_PARSE_FUNC_GETTER + prop_type - PROP_TYPE_GET;
            } else {
                func_type = JS_PARSE_FUNC_METHOD;
                if (prop_type == PROP_TYPE_STAR)
                    func_kind = JS_FUNC_GENERATOR;
                else if (prop_type == PROP_TYPE_ASYNC)
                    func_kind = JS_FUNC_ASYNC;
                else if (prop_type == PROP_TYPE_ASYNC_STAR)
                    func_kind = JS_FUNC_ASYNC_GENERATOR;
            }
            if (js_parse_function_decl(s, func_type, func_kind, JS_ATOM_NULL,
                                       start_ptr, start_line))
                goto fail;
            if (name == JS_ATOM_NULL) {
                emit_op(s, OP_define_method_computed);
            } else {
                emit_op(s, OP_define_method);
                emit_atom(s, name);
            }
            if (is_getset) {
                op_flags = OP_DEFINE_METHOD_GETTER +
                    prop_type - PROP_TYPE_GET;
            } else {
                op_flags = OP_DEFINE_METHOD_METHOD;
            }
            emit_u8(s, op_flags | OP_DEFINE_METHOD_ENUMERABLE);
        } else {
            if (js_parse_expect(s, ':'))
                goto fail;
            if (js_parse_assign_expr(s))
                goto fail;
            if (name == JS_ATOM_NULL) {
                set_object_name_computed(s);
                emit_op(s, OP_define_array_el);
                emit_op(s, OP_drop);
            } else if (name == JS_ATOM___proto__) {
                if (has_proto) {
                    js_parse_error(s, "duplicate __proto__ property name");
                    goto fail;
                }
                emit_op(s, OP_set_proto);
                has_proto = TRUE;
            } else {
                set_object_name(s, name);
                emit_op(s, OP_define_field);
                emit_atom(s, name);
            }
        }
        JS_FreeAtom(s->ctx, name);
    next:
        name = JS_ATOM_NULL;
        if (s->token.val != ',')
            break;
        if (next_token(s))
            goto fail;
    }
    if (js_parse_expect(s, '}'))
        goto fail;
    return 0;
 fail:
    JS_FreeAtom(s->ctx, name);
    return -1;
}

/* return TRUE if a regexp literal is allowed after this token */
static BOOL is_regexp_allowed(int tok)
{
    switch (tok) {
    case TOK_NUMBER:
    case TOK_STRING:
    case TOK_REGEXP:
    case TOK_DEC:
    case TOK_INC:
    case TOK_NULL:
    case TOK_FALSE:
    case TOK_TRUE:
    case TOK_THIS:
    case ')':
    case ']':
    case '}': /* XXX: regexp may occur after */
    case TOK_IDENT:
        return FALSE;
    default:
        return TRUE;
    }
}

static __exception int js_parse_regexp(JSParseState *s)
{
    const uint8_t *p;
    BOOL in_class;
    StringBuffer b_s, *b = &b_s;
    StringBuffer b2_s, *b2 = &b2_s;
    uint32_t c;
    p = s->buf_ptr;
    p++;
    in_class = FALSE;
    if (string_buffer_init(s->ctx, b, 32))
        return -1;
    if (string_buffer_init(s->ctx, b2, 1))
        goto fail;
    for(;;) {
        if (p >= s->buf_end) {
        eof_error:
            js_parse_error(s, "unexpected end of regexp");
            goto fail;
        }
        c = *p++;
        if (c == '\n' || c == '\r') {
            goto eol_error;
        } else if (c == '/') {
            if (!in_class)
                break;
        } else if (c == '[') {
            in_class = TRUE;
        } else if (c == ']') {
            /* XXX: incorrect as the first character in a class */
            in_class = FALSE;
        } else if (c == '\\') {
            if (string_buffer_putc8(b, c))
                goto fail;
            c = *p++;
            if (c == '\n' || c == '\r')
                goto eol_error;
            else if (c == '\0' && p >= s->buf_end)
                goto eof_error;
            else if (c >= 0x80) {
                const uint8_t *p_next;
                c = unicode_from_utf8(p - 1, UTF8_CHAR_LEN_MAX, &p_next);
                if (c > 0x10FFFF) {
                    goto invalid_utf8;
                }
                p = p_next;
                if (c == CP_LS || c == CP_PS)
                    goto eol_error;
            }
        } else if (c >= 0x80) {
            const uint8_t *p_next;
            c = unicode_from_utf8(p - 1, UTF8_CHAR_LEN_MAX, &p_next);
            if (c > 0x10FFFF) {
            invalid_utf8:
                js_parse_error(s, "invalid UTF-8 sequence");
                goto fail;
            }
            p = p_next;
            /* LS or PS are considered as line terminator */
            if (c == CP_LS || c == CP_PS) {
            eol_error:
                js_parse_error(s, "unexpected line terminator in regexp");
                goto fail;
            }
        }
        if (string_buffer_putc(b, c))
            goto fail;
    }
    /* flags */
    for(;;) {
        const uint8_t *p_next = p;
        c = *p_next++;
        if (c >= 0x80) {
            c = unicode_from_utf8(p, UTF8_CHAR_LEN_MAX, &p_next);
            if (c > 0x10FFFF) {
                goto invalid_utf8;
            }
        }
        if (!lre_js_is_ident_next(c))
            break;
        if (string_buffer_putc(b2, c))
            goto fail;
        p = p_next;
    }
    s->token.val = TOK_REGEXP;
    s->token.u.regexp.body = string_buffer_end(b);
    s->token.u.regexp.flags = string_buffer_end(b2);
    s->buf_ptr = p;
    return 0;
 fail:
    string_buffer_free(b);
    string_buffer_free(b2);
    return -1;
}

/* XXX: improve speed with early bailout */
/* XXX: no longer works if regexps are present. Could use previous
   regexp parsing heuristics to handle most cases */
static int js_parse_skip_parens_token(JSParseState *s, int *pbits, BOOL no_line_terminator)
{
    char state[256];
    size_t level = 0;
    JSParsePos pos;
    int last_tok, tok = TOK_EOF;
    int c, tok_len, bits = 0;
    /* protect from underflow */
    state[level++] = 0;
    js_parse_get_pos(s, &pos);
    last_tok = 0;
    for (;;) {
        switch(s->token.val) {
        case '(':
        case '[':
        case '{':
            if (level >= sizeof(state))
                goto done;
            state[level++] = s->token.val;
            break;
        case ')':
            if (state[--level] != '(')
                goto done;
            break;
        case ']':
            if (state[--level] != '[')
                goto done;
            break;
        case '}':
            c = state[--level];
            if (c == '`') {
                /* continue the parsing of the template */
                free_token(s, &s->token);
                /* Resume TOK_TEMPLATE parsing (s->token.line_num and
                 * s->token.ptr are OK) */
                s->got_lf = FALSE;
                s->last_line_num = s->token.line_num;
                if (js_parse_template_part(s, s->buf_ptr))
                    goto done;
                goto handle_template;
            } else if (c != '{') {
                goto done;
            }
            break;
        case TOK_TEMPLATE:
        handle_template:
            if (s->token.u.str.sep != '`') {
                /* '${' inside the template : closing '}' and continue
                   parsing the template */
                if (level >= sizeof(state))
                    goto done;
                state[level++] = '`';
            }
            break;
        case TOK_EOF:
            goto done;
        case ';':
            if (level == 2) {
                bits |= SKIP_HAS_SEMI;
            }
            break;
        case TOK_ELLIPSIS:
            if (level == 2) {
                bits |= SKIP_HAS_ELLIPSIS;
            }
            break;
        case '=':
            bits |= SKIP_HAS_ASSIGNMENT;
            break;
        case TOK_DIV_ASSIGN:
            tok_len = 2;
            goto parse_regexp;
        case '/':
            tok_len = 1;
        parse_regexp:
            if (is_regexp_allowed(last_tok)) {
                s->buf_ptr -= tok_len;
                if (js_parse_regexp(s)) {
                    /* XXX: should clear the exception */
                    goto done;
                }
            }
            break;
        }
        /* last_tok is only used to recognize regexps */
        if (s->token.val == TOK_IDENT &&
            (token_is_pseudo_keyword(s, JS_ATOM_of) ||
             token_is_pseudo_keyword(s, JS_ATOM_yield))) {
            last_tok = TOK_OF;
        } else {
            last_tok = s->token.val;
        }
        if (next_token(s)) {
            /* XXX: should clear the exception generated by next_token() */
            break;
        }
        if (level <= 1) {
            tok = s->token.val;
            if (token_is_pseudo_keyword(s, JS_ATOM_of))
                tok = TOK_OF;
            if (no_line_terminator && s->last_line_num != s->token.line_num)
                tok = '\n';
            break;
        }
    }
 done:
    if (pbits) {
        *pbits = bits;
    }
    if (js_parse_seek_token(s, &pos))
        return -1;
    return tok;
}


static int js_parse_check_duplicate_parameter(JSParseState *s, JSAtom name)
{
    /* Check for duplicate parameter names */
    JSFunctionDef *fd = s->cur_func;
    int i;
    for (i = 0; i < fd->arg_count; i++) {
        if (fd->args[i].var_name == name)
            goto duplicate;
    }
    for (i = 0; i < fd->var_count; i++) {
        if (fd->vars[i].var_name == name)
            goto duplicate;
    }
    return 0;
duplicate:
    return js_parse_error(s, "duplicate parameter names not allowed in this context");
}

static JSAtom js_parse_destructuring_var(JSParseState *s, int tok, int is_arg)
{
    JSAtom name;
    if (!(s->token.val == TOK_IDENT && !s->token.u.ident.is_reserved)
    ||  ((s->cur_func->js_mode & JS_MODE_STRICT) &&
         (s->token.u.ident.atom == JS_ATOM_eval || s->token.u.ident.atom == JS_ATOM_arguments))) {
        js_parse_error(s, "invalid destructuring target");
        return JS_ATOM_NULL;
    }
    name = JS_DupAtom(s->ctx, s->token.u.ident.atom);
    if (is_arg && js_parse_check_duplicate_parameter(s, name))
        goto fail;
    if (next_token(s))
        goto fail;
    return name;
fail:
    JS_FreeAtom(s->ctx, name);
    return JS_ATOM_NULL;
}

static __exception int js_parse_expr_paren(JSParseState *s)
{
    if (js_parse_expect(s, '('))
        return -1;
    if (js_parse_expr(s))
        return -1;
    if (js_parse_expect(s, ')'))
        return -1;
    return 0;
}

static int js_parse_error_reserved_identifier(JSParseState *s)
{
    char buf1[ATOM_GET_STR_BUF_SIZE];
    return js_parse_error(s, "'%s' is a reserved identifier",
                          JS_AtomGetStr(s->ctx, buf1, sizeof(buf1),
                                        s->token.u.ident.atom));
}

static __exception int js_parse_left_hand_side_expr(JSParseState *s)
{
    return js_parse_postfix_expr(s, PF_POSTFIX_CALL);
}

/* add a private field variable in the current scope */
static int add_private_class_field(JSParseState *s, JSFunctionDef *fd,
                                   JSAtom name, JSVarKindEnum var_kind)
{
    JSContext *ctx = s->ctx;
    JSVarDef *vd;
    int idx;
    idx = add_scope_var(ctx, fd, name, var_kind);
    if (idx < 0)
        return idx;
    vd = &fd->vars[idx];
    vd->is_lexical = 1;
    vd->is_const = 1;
    return idx;
}

static BOOL js_is_live_code(JSParseState *s) {
    switch (get_prev_opcode(s->cur_func)) {
    case OP_tail_call:
    case OP_tail_call_method:
    case OP_return:
    case OP_return_undef:
    case OP_return_async:
    case OP_throw:
    case OP_throw_error:
    case OP_goto:
#if SHORT_OPCODES
    case OP_goto8:
    case OP_goto16:
#endif
    case OP_ret:
        return FALSE;
    default:
        return TRUE;
    }
}

/* return label or -1 if dead code */
static int emit_goto(JSParseState *s, int opcode, int label)
{
    if (js_is_live_code(s)) {
        if (label < 0)
            label = new_label(s);
        emit_op(s, opcode);
        emit_u32(s, label);
        s->cur_func->label_slots[label].ref_count++;
        return label;
    }
    return -1;
}

/* create a function to initialize class fields */
static JSFunctionDef *js_parse_function_class_fields_init(JSParseState *s)
{
    JSFunctionDef *fd;
    fd = js_new_function_def(s->ctx, s->cur_func, FALSE, FALSE,
                             s->filename, 0);
    if (!fd)
        return NULL;
    fd->func_name = JS_ATOM_NULL;
    fd->has_prototype = FALSE;
    fd->has_home_object = TRUE;
    fd->has_arguments_binding = FALSE;
    fd->has_this_binding = TRUE;
    fd->is_derived_class_constructor = FALSE;
    fd->new_target_allowed = TRUE;
    fd->super_call_allowed = FALSE;
    fd->super_allowed = fd->has_home_object;
    fd->arguments_allowed = FALSE;
    fd->func_kind = JS_FUNC_NORMAL;
    fd->func_type = JS_PARSE_FUNC_METHOD;
    return fd;
}

static __exception int emit_class_init_start(JSParseState *s,
                                             ClassFieldsDef *cf)
{
    int label_add_brand;
    cf->fields_init_fd = js_parse_function_class_fields_init(s);
    if (!cf->fields_init_fd)
        return -1;
    s->cur_func = cf->fields_init_fd;
    /* XXX: would be better to add the code only if needed, maybe in a
       later pass */
    emit_op(s, OP_push_false); /* will be patched later */
    cf->brand_push_pos = cf->fields_init_fd->last_opcode_pos;
    label_add_brand = emit_goto(s, OP_if_false, -1);
    emit_op(s, OP_scope_get_var);
    emit_atom(s, JS_ATOM_this);
    emit_u16(s, 0);
    emit_op(s, OP_scope_get_var);
    emit_atom(s, JS_ATOM_home_object);
    emit_u16(s, 0);
    emit_op(s, OP_add_brand);
    emit_label(s, label_add_brand);
    s->cur_func = s->cur_func->parent;
    return 0;
}

static __exception int add_brand(JSParseState *s, ClassFieldsDef *cf)
{
    if (!cf->has_brand) {
        /* define the brand field in 'this' of the initializer */
        if (!cf->fields_init_fd) {
            if (emit_class_init_start(s, cf))
                return -1;
        }
        /* patch the start of the function to enable the OP_add_brand code */
        cf->fields_init_fd->byte_code.buf[cf->brand_push_pos] = OP_push_true;
        cf->has_brand = TRUE;
    }
    return 0;
}

static JSAtom js_atom_concat_num(JSContext *ctx, JSAtom name, uint32_t n)
{
    char buf[16];
    snprintf(buf, sizeof(buf), "%u", n);
    return js_atom_concat_str(ctx, name, buf);
}

/* XXX: could generate specific bytecode */
static __exception int js_parse_class_default_ctor(JSParseState *s,
                                                   BOOL has_super,
                                                   JSFunctionDef **pfd)
{
    JSParsePos pos;
    const char *str;
    int ret, line_num;
    JSParseFunctionEnum func_type;
    const uint8_t *saved_buf_end;
    js_parse_get_pos(s, &pos);
    if (has_super) {
        /* spec change: no argument evaluation */
        str = "(){super(...arguments);}";
        func_type = JS_PARSE_FUNC_DERIVED_CLASS_CONSTRUCTOR;
    } else {
        str = "(){}";
        func_type = JS_PARSE_FUNC_CLASS_CONSTRUCTOR;
    }
    line_num = s->token.line_num;
    saved_buf_end = s->buf_end;
    s->buf_ptr = (uint8_t *)str;
    s->buf_end = (uint8_t *)(str + strlen(str));
    ret = next_token(s);
    if (!ret) {
        ret = js_parse_function_decl2(s, func_type, JS_FUNC_NORMAL,
                                      JS_ATOM_NULL, (uint8_t *)str,
                                      line_num, JS_PARSE_EXPORT_NONE, pfd);
    }
    s->buf_end = saved_buf_end;
    ret |= js_parse_seek_token(s, &pos);
    return ret;
}

static void emit_class_init_end(JSParseState *s, ClassFieldsDef *cf)
{
    int cpool_idx;
    s->cur_func = cf->fields_init_fd;
    emit_op(s, OP_return_undef);
    s->cur_func = s->cur_func->parent;
    cpool_idx = cpool_add(s, JS_NULL);
    cf->fields_init_fd->parent_cpool_idx = cpool_idx;
    emit_op(s, OP_fclosure);
    emit_u32(s, cpool_idx);
    emit_op(s, OP_set_home_object);
}

static __exception int js_parse_class(JSParseState *s, BOOL is_class_expr,
                                      JSParseExportEnum export_flag)
{
    JSContext *ctx = s->ctx;
    JSFunctionDef *fd = s->cur_func;
    JSAtom name = JS_ATOM_NULL, class_name = JS_ATOM_NULL, class_name1;
    JSAtom class_var_name = JS_ATOM_NULL;
    JSFunctionDef *method_fd, *ctor_fd;
    int saved_js_mode, class_name_var_idx, prop_type, ctor_cpool_offset;
    int class_flags = 0, i, define_class_offset;
    BOOL is_static, is_private;
    const uint8_t *class_start_ptr = s->token.ptr;
    const uint8_t *start_ptr;
    ClassFieldsDef class_fields[2];
    /* classes are parsed and executed in strict mode */
    saved_js_mode = fd->js_mode;
    fd->js_mode |= JS_MODE_STRICT;
    if (next_token(s))
        goto fail;
    if (s->token.val == TOK_IDENT) {
        if (s->token.u.ident.is_reserved) {
            js_parse_error_reserved_identifier(s);
            goto fail;
        }
        class_name = JS_DupAtom(ctx, s->token.u.ident.atom);
        if (next_token(s))
            goto fail;
    } else if (!is_class_expr && export_flag != JS_PARSE_EXPORT_DEFAULT) {
        js_parse_error(s, "class statement requires a name");
        goto fail;
    }
    if (!is_class_expr) {
        if (class_name == JS_ATOM_NULL)
            class_var_name = JS_ATOM__default_; /* export default */
        else
            class_var_name = class_name;
        class_var_name = JS_DupAtom(ctx, class_var_name);
    }
    push_scope(s);
    if (s->token.val == TOK_EXTENDS) {
        class_flags = JS_DEFINE_CLASS_HAS_HERITAGE;
        if (next_token(s))
            goto fail;
        if (js_parse_left_hand_side_expr(s))
            goto fail;
    } else {
        emit_op(s, OP_undefined);
    }
    /* add a 'const' definition for the class name */
    if (class_name != JS_ATOM_NULL) {
        class_name_var_idx = define_var(s, fd, class_name, JS_VAR_DEF_CONST);
        if (class_name_var_idx < 0)
            goto fail;
    }
    if (js_parse_expect(s, '{'))
        goto fail;
    /* this scope contains the private fields */
    push_scope(s);
    emit_op(s, OP_push_const);
    ctor_cpool_offset = fd->byte_code.size;
    emit_u32(s, 0); /* will be patched at the end of the class parsing */
    if (class_name == JS_ATOM_NULL) {
        if (class_var_name != JS_ATOM_NULL)
            class_name1 = JS_ATOM_default;
        else
            class_name1 = JS_ATOM_empty_string;
    } else {
        class_name1 = class_name;
    }
    emit_op(s, OP_define_class);
    emit_atom(s, class_name1);
    emit_u8(s, class_flags);
    define_class_offset = fd->last_opcode_pos;
    for(i = 0; i < 2; i++) {
        ClassFieldsDef *cf = &class_fields[i];
        cf->fields_init_fd = NULL;
        cf->computed_fields_count = 0;
        cf->has_brand = FALSE;
    }
    ctor_fd = NULL;
    while (s->token.val != '}') {
        if (s->token.val == ';') {
            if (next_token(s))
                goto fail;
            continue;
        }
        is_static = (s->token.val == TOK_STATIC);
        prop_type = -1;
        if (is_static) {
            if (next_token(s))
                goto fail;
            /* allow "static" field name */
            if (s->token.val == ';' || s->token.val == '=') {
                is_static = FALSE;
                name = JS_DupAtom(ctx, JS_ATOM_static);
                prop_type = PROP_TYPE_IDENT;
            }
        }
        if (is_static)
            emit_op(s, OP_swap);
        start_ptr = s->token.ptr;
        if (prop_type < 0) {
            prop_type = js_parse_property_name(s, &name, TRUE, FALSE, TRUE);
            if (prop_type < 0)
                goto fail;
        }
        is_private = prop_type & PROP_TYPE_PRIVATE;
        prop_type &= ~PROP_TYPE_PRIVATE;
        if ((name == JS_ATOM_constructor && !is_static &&
             prop_type != PROP_TYPE_IDENT) ||
            (name == JS_ATOM_prototype && is_static) ||
            name == JS_ATOM_hash_constructor) {
            js_parse_error(s, "invalid method name");
            goto fail;
        }
        if (prop_type == PROP_TYPE_GET || prop_type == PROP_TYPE_SET) {
            BOOL is_set = prop_type - PROP_TYPE_GET;
            JSFunctionDef *method_fd;
            if (is_private) {
                int idx, var_kind;
                idx = find_private_class_field(ctx, fd, name, fd->scope_level);
                if (idx >= 0) {
                    var_kind = fd->vars[idx].var_kind;
                    if (var_kind == JS_VAR_PRIVATE_FIELD ||
                        var_kind == JS_VAR_PRIVATE_METHOD ||
                        var_kind == JS_VAR_PRIVATE_GETTER_SETTER ||
                        var_kind == (JS_VAR_PRIVATE_GETTER + is_set)) {
                        goto private_field_already_defined;
                    }
                    fd->vars[idx].var_kind = JS_VAR_PRIVATE_GETTER_SETTER;
                } else {
                    if (add_private_class_field(s, fd, name,
                                                JS_VAR_PRIVATE_GETTER + is_set) < 0)
                        goto fail;
                }
                if (add_brand(s, &class_fields[is_static]) < 0)
                    goto fail;
            }
            if (js_parse_function_decl2(s, JS_PARSE_FUNC_GETTER + is_set,
                                        JS_FUNC_NORMAL, JS_ATOM_NULL,
                                        start_ptr, s->token.line_num,
                                        JS_PARSE_EXPORT_NONE, &method_fd))
                goto fail;
            if (is_private) {
                method_fd->need_home_object = TRUE; /* needed for brand check */
                emit_op(s, OP_set_home_object);
                /* XXX: missing function name */
                emit_op(s, OP_scope_put_var_init);
                if (is_set) {
                    JSAtom setter_name;
                    int ret;
                    setter_name = get_private_setter_name(ctx, name);
                    if (setter_name == JS_ATOM_NULL)
                        goto fail;
                    emit_atom(s, setter_name);
                    ret = add_private_class_field(s, fd, setter_name,
                                                  JS_VAR_PRIVATE_SETTER);
                    JS_FreeAtom(ctx, setter_name);
                    if (ret < 0)
                        goto fail;
                } else {
                    emit_atom(s, name);
                }
                emit_u16(s, s->cur_func->scope_level);
            } else {
                if (name == JS_ATOM_NULL) {
                    emit_op(s, OP_define_method_computed);
                } else {
                    emit_op(s, OP_define_method);
                    emit_atom(s, name);
                }
                emit_u8(s, OP_DEFINE_METHOD_GETTER + is_set);
            }
        } else if (prop_type == PROP_TYPE_IDENT && s->token.val != '(') {
            ClassFieldsDef *cf = &class_fields[is_static];
            JSAtom field_var_name = JS_ATOM_NULL;
            /* class field */
            /* XXX: spec: not consistent with method name checks */
            if (name == JS_ATOM_constructor || name == JS_ATOM_prototype) {
                js_parse_error(s, "invalid field name");
                goto fail;
            }
            if (is_private) {
                if (find_private_class_field(ctx, fd, name,
                                             fd->scope_level) >= 0) {
                    goto private_field_already_defined;
                }
                if (add_private_class_field(s, fd, name,
                                            JS_VAR_PRIVATE_FIELD) < 0)
                    goto fail;
                emit_op(s, OP_private_symbol);
                emit_atom(s, name);
                emit_op(s, OP_scope_put_var_init);
                emit_atom(s, name);
                emit_u16(s, s->cur_func->scope_level);
            }
            if (!cf->fields_init_fd) {
                if (emit_class_init_start(s, cf))
                    goto fail;
            }
            if (name == JS_ATOM_NULL ) {
                /* save the computed field name into a variable */
                field_var_name = js_atom_concat_num(ctx, JS_ATOM_computed_field + is_static, cf->computed_fields_count);
                if (field_var_name == JS_ATOM_NULL)
                    goto fail;
                if (define_var(s, fd, field_var_name, JS_VAR_DEF_CONST) < 0) {
                    JS_FreeAtom(ctx, field_var_name);
                    goto fail;
                }
                emit_op(s, OP_to_propkey);
                emit_op(s, OP_scope_put_var_init);
                emit_atom(s, field_var_name);
                emit_u16(s, s->cur_func->scope_level);
            }
            s->cur_func = cf->fields_init_fd;
            emit_op(s, OP_scope_get_var);
            emit_atom(s, JS_ATOM_this);
            emit_u16(s, 0);
            if (name == JS_ATOM_NULL) {
                emit_op(s, OP_scope_get_var);
                emit_atom(s, field_var_name);
                emit_u16(s, s->cur_func->scope_level);
                cf->computed_fields_count++;
                JS_FreeAtom(ctx, field_var_name);
            } else if (is_private) {
                emit_op(s, OP_scope_get_var);
                emit_atom(s, name);
                emit_u16(s, s->cur_func->scope_level);
            }
            if (s->token.val == '=') {
                if (next_token(s))
                    goto fail;
                if (js_parse_assign_expr(s))
                    goto fail;
            } else {
                emit_op(s, OP_undefined);
            }
            if (is_private) {
                set_object_name_computed(s);
                emit_op(s, OP_define_private_field);
            } else if (name == JS_ATOM_NULL) {
                set_object_name_computed(s);
                emit_op(s, OP_define_array_el);
                emit_op(s, OP_drop);
            } else {
                set_object_name(s, name);
                emit_op(s, OP_define_field);
                emit_atom(s, name);
            }
            s->cur_func = s->cur_func->parent;
            if (js_parse_expect_semi(s))
                goto fail;
        } else {
            JSParseFunctionEnum func_type;
            JSFunctionKindEnum func_kind;
            func_type = JS_PARSE_FUNC_METHOD;
            func_kind = JS_FUNC_NORMAL;
            if (prop_type == PROP_TYPE_STAR) {
                func_kind = JS_FUNC_GENERATOR;
            } else if (prop_type == PROP_TYPE_ASYNC) {
                func_kind = JS_FUNC_ASYNC;
            } else if (prop_type == PROP_TYPE_ASYNC_STAR) {
                func_kind = JS_FUNC_ASYNC_GENERATOR;
            } else if (name == JS_ATOM_constructor && !is_static) {
                if (ctor_fd) {
                    js_parse_error(s, "property constructor appears more than once");
                    goto fail;
                }
                if (class_flags & JS_DEFINE_CLASS_HAS_HERITAGE)
                    func_type = JS_PARSE_FUNC_DERIVED_CLASS_CONSTRUCTOR;
                else
                    func_type = JS_PARSE_FUNC_CLASS_CONSTRUCTOR;
            }
            if (is_private) {
                if (add_brand(s, &class_fields[is_static]) < 0)
                    goto fail;
            }
            if (js_parse_function_decl2(s, func_type, func_kind, JS_ATOM_NULL, start_ptr, s->token.line_num, JS_PARSE_EXPORT_NONE, &method_fd))
                goto fail;
            if (func_type == JS_PARSE_FUNC_DERIVED_CLASS_CONSTRUCTOR ||
                func_type == JS_PARSE_FUNC_CLASS_CONSTRUCTOR) {
                ctor_fd = method_fd;
            } else if (is_private) {
                method_fd->need_home_object = TRUE; /* needed for brand check */
                if (find_private_class_field(ctx, fd, name,
                                             fd->scope_level) >= 0) {
                private_field_already_defined:
                    js_parse_error(s, "private class field is already defined");
                    goto fail;
                }
                if (add_private_class_field(s, fd, name,
                                            JS_VAR_PRIVATE_METHOD) < 0)
                    goto fail;
                emit_op(s, OP_set_home_object);
                emit_op(s, OP_set_name);
                emit_atom(s, name);
                emit_op(s, OP_scope_put_var_init);
                emit_atom(s, name);
                emit_u16(s, s->cur_func->scope_level);
            } else {
                if (name == JS_ATOM_NULL) {
                    emit_op(s, OP_define_method_computed);
                } else {
                    emit_op(s, OP_define_method);
                    emit_atom(s, name);
                }
                emit_u8(s, OP_DEFINE_METHOD_METHOD);
            }
        }
        if (is_static)
            emit_op(s, OP_swap);
        JS_FreeAtom(ctx, name);
        name = JS_ATOM_NULL;
    }
    if (s->token.val != '}') {
        js_parse_error(s, "expecting '%c'", '}');
        goto fail;
    }
    if (!ctor_fd) {
        if (js_parse_class_default_ctor(s, class_flags & JS_DEFINE_CLASS_HAS_HERITAGE, &ctor_fd))
            goto fail;
    }
    /* patch the constant pool index for the constructor */
    put_u32(fd->byte_code.buf + ctor_cpool_offset, ctor_fd->parent_cpool_idx);
    /* store the class source code in the constructor. */
    if (!(fd->js_mode & JS_MODE_STRIP)) {
        js_free(ctx, ctor_fd->source);
        ctor_fd->source_len = s->buf_ptr - class_start_ptr;
        ctor_fd->source = js_strndup(ctx, (const char *)class_start_ptr,
                                     ctor_fd->source_len);
        if (!ctor_fd->source)
            goto fail;
    }
    /* consume the '}' */
    if (next_token(s))
        goto fail;
    /* store the function to initialize the fields to that it can be
       referenced by the constructor */
    {
        ClassFieldsDef *cf = &class_fields[0];
        int var_idx;
        var_idx = define_var(s, fd, JS_ATOM_class_fields_init,
                             JS_VAR_DEF_CONST);
        if (var_idx < 0)
            goto fail;
        if (cf->fields_init_fd) {
            emit_class_init_end(s, cf);
        } else {
            emit_op(s, OP_undefined);
        }
        emit_op(s, OP_scope_put_var_init);
        emit_atom(s, JS_ATOM_class_fields_init);
        emit_u16(s, s->cur_func->scope_level);
    }
    /* drop the prototype */
    emit_op(s, OP_drop);
    /* initialize the static fields */
    if (class_fields[1].fields_init_fd != NULL) {
        ClassFieldsDef *cf = &class_fields[1];
        emit_op(s, OP_dup);
        emit_class_init_end(s, cf);
        emit_op(s, OP_call_method);
        emit_u16(s, 0);
        emit_op(s, OP_drop);
    }
    if (class_name != JS_ATOM_NULL) {
        /* store the class name in the scoped class name variable (it
           is independent from the class statement variable
           definition) */
        emit_op(s, OP_dup);
        emit_op(s, OP_scope_put_var_init);
        emit_atom(s, class_name);
        emit_u16(s, fd->scope_level);
    }
    pop_scope(s);
    pop_scope(s);
    /* the class statements have a block level scope */
    if (class_var_name != JS_ATOM_NULL) {
        if (define_var(s, fd, class_var_name, JS_VAR_DEF_LET) < 0)
            goto fail;
        emit_op(s, OP_scope_put_var_init);
        emit_atom(s, class_var_name);
        emit_u16(s, fd->scope_level);
    } else {
        if (class_name == JS_ATOM_NULL) {
            /* cannot use OP_set_name because the name of the class
               must be defined before the static initializers are
               executed */
            emit_op(s, OP_set_class_name);
            emit_u32(s, fd->last_opcode_pos + 1 - define_class_offset);
        }
    }
    if (export_flag != JS_PARSE_EXPORT_NONE) {
        if (!add_export_entry(s, fd->module,
                              class_var_name,
                              export_flag == JS_PARSE_EXPORT_NAMED ? class_var_name : JS_ATOM_default,
                              JS_EXPORT_TYPE_LOCAL))
            goto fail;
    }
    JS_FreeAtom(ctx, class_name);
    JS_FreeAtom(ctx, class_var_name);
    fd->js_mode = saved_js_mode;
    return 0;
 fail:
    JS_FreeAtom(ctx, name);
    JS_FreeAtom(ctx, class_name);
    JS_FreeAtom(ctx, class_var_name);
    fd->js_mode = saved_js_mode;
    return -1;
}

static __exception int get_lvalue(JSParseState *s, int *popcode, int *pscope,
                                  JSAtom *pname, int *plabel, int *pdepth, BOOL keep,
                                  int tok)
{
    JSFunctionDef *fd;
    int opcode, scope, label, depth;
    JSAtom name;
    /* we check the last opcode to get the lvalue type */
    fd = s->cur_func;
    scope = 0;
    name = JS_ATOM_NULL;
    label = -1;
    depth = 0;
    switch(opcode = get_prev_opcode(fd)) {
    case OP_scope_get_var:
        name = get_u32(fd->byte_code.buf + fd->last_opcode_pos + 1);
        scope = get_u16(fd->byte_code.buf + fd->last_opcode_pos + 5);
        if ((name == JS_ATOM_arguments || name == JS_ATOM_eval) &&
            (fd->js_mode & JS_MODE_STRICT)) {
            return js_parse_error(s, "invalid lvalue in strict mode");
        }
        if (name == JS_ATOM_this || name == JS_ATOM_new_target)
            goto invalid_lvalue;
        depth = 2;  /* will generate OP_get_ref_value */
        break;
    case OP_get_field:
        name = get_u32(fd->byte_code.buf + fd->last_opcode_pos + 1);
        depth = 1;
        break;
    case OP_scope_get_private_field:
        name = get_u32(fd->byte_code.buf + fd->last_opcode_pos + 1);
        scope = get_u16(fd->byte_code.buf + fd->last_opcode_pos + 5);
        depth = 1;
        break;
    case OP_get_array_el:
        depth = 2;
        break;
    case OP_get_super_value:
        depth = 3;
        break;
    default:
    invalid_lvalue:
        if (tok == TOK_FOR) {
            return js_parse_error(s, "invalid for in/of left hand-side");
        } else if (tok == TOK_INC || tok == TOK_DEC) {
            return js_parse_error(s, "invalid increment/decrement operand");
        } else if (tok == '[' || tok == '{') {
            return js_parse_error(s, "invalid destructuring target");
        } else {
            return js_parse_error(s, "invalid assignment left-hand side");
        }
    }
    /* remove the last opcode */
    fd->byte_code.size = fd->last_opcode_pos;
    fd->last_opcode_pos = -1;
    if (keep) {
        /* get the value but keep the object/fields on the stack */
        switch(opcode) {
        case OP_scope_get_var:
            label = new_label(s);
            emit_op(s, OP_scope_make_ref);
            emit_atom(s, name);
            emit_u32(s, label);
            emit_u16(s, scope);
            update_label(fd, label, 1);
            emit_op(s, OP_get_ref_value);
            opcode = OP_get_ref_value;
            break;
        case OP_get_field:
            emit_op(s, OP_get_field2);
            emit_atom(s, name);
            break;
        case OP_scope_get_private_field:
            emit_op(s, OP_scope_get_private_field2);
            emit_atom(s, name);
            emit_u16(s, scope);
            break;
        case OP_get_array_el:
            /* XXX: replace by a single opcode ? */
            emit_op(s, OP_to_propkey2);
            emit_op(s, OP_dup2);
            emit_op(s, OP_get_array_el);
            break;
        case OP_get_super_value:
            emit_op(s, OP_to_propkey);
            emit_op(s, OP_dup3);
            emit_op(s, OP_get_super_value);
            break;
        default:
            abort();
        }
    } else {
        switch(opcode) {
        case OP_scope_get_var:
            label = new_label(s);
            emit_op(s, OP_scope_make_ref);
            emit_atom(s, name);
            emit_u32(s, label);
            emit_u16(s, scope);
            update_label(fd, label, 1);
            opcode = OP_get_ref_value;
            break;
        case OP_get_array_el:
            emit_op(s, OP_to_propkey2);
            break;
        case OP_get_super_value:
            emit_op(s, OP_to_propkey);
            break;
        }
    }
    *popcode = opcode;
    *pscope = scope;
    /* name has refcount for OP_get_field and OP_get_ref_value,
       and JS_ATOM_NULL for other opcodes */
    *pname = name;
    *plabel = label;
    if (pdepth)
        *pdepth = depth;
    return 0;
}

static __exception int js_define_var(JSParseState *s, JSAtom name, int tok)
{
    JSFunctionDef *fd = s->cur_func;
    JSVarDefEnum var_def_type;
    if (name == JS_ATOM_yield && fd->func_kind == JS_FUNC_GENERATOR) {
        return js_parse_error(s, "yield is a reserved identifier");
    }
    if ((name == JS_ATOM_arguments || name == JS_ATOM_eval)
    &&  (fd->js_mode & JS_MODE_STRICT)) {
        return js_parse_error(s, "invalid variable name in strict mode");
    }
    if ((name == JS_ATOM_let || name == JS_ATOM_undefined)
    &&  (tok == TOK_LET || tok == TOK_CONST)) {
        return js_parse_error(s, "invalid lexical variable name");
    }
    switch(tok) {
    case TOK_LET:
        var_def_type = JS_VAR_DEF_LET;
        break;
    case TOK_CONST:
        var_def_type = JS_VAR_DEF_CONST;
        break;
    case TOK_VAR:
        var_def_type = JS_VAR_DEF_VAR;
        break;
    case TOK_CATCH:
        var_def_type = JS_VAR_DEF_CATCH;
        break;
    default:
        abort();
    }
    if (define_var(s, fd, name, var_def_type) < 0)
        return -1;
    return 0;
}

/* name has a live reference. 'is_let' is only used with opcode =
   OP_scope_get_var which is never generated by get_lvalue(). */
static void put_lvalue(JSParseState *s, int opcode, int scope,
                       JSAtom name, int label, PutLValueEnum special,
                       BOOL is_let)
{
    switch(opcode) {
    case OP_get_field:
    case OP_scope_get_private_field:
        /* depth = 1 */
        switch(special) {
        case PUT_LVALUE_NOKEEP:
        case PUT_LVALUE_NOKEEP_DEPTH:
            break;
        case PUT_LVALUE_KEEP_TOP:
            emit_op(s, OP_insert2); /* obj v -> v obj v */
            break;
        case PUT_LVALUE_KEEP_SECOND:
            emit_op(s, OP_perm3); /* obj v0 v -> v0 obj v */
            break;
        case PUT_LVALUE_NOKEEP_BOTTOM:
            emit_op(s, OP_swap);
            break;
        default:
            abort();
        }
        break;
    case OP_get_array_el:
    case OP_get_ref_value:
        /* depth = 2 */
        if (opcode == OP_get_ref_value) {
            JS_FreeAtom(s->ctx, name);
            emit_label(s, label);
        }
        switch(special) {
        case PUT_LVALUE_NOKEEP:
            emit_op(s, OP_nop); /* will trigger optimization */
            break;
        case PUT_LVALUE_NOKEEP_DEPTH:
            break;
        case PUT_LVALUE_KEEP_TOP:
            emit_op(s, OP_insert3); /* obj prop v -> v obj prop v */
            break;
        case PUT_LVALUE_KEEP_SECOND:
            emit_op(s, OP_perm4); /* obj prop v0 v -> v0 obj prop v */
            break;
        case PUT_LVALUE_NOKEEP_BOTTOM:
            emit_op(s, OP_rot3l);
            break;
        default:
            abort();
        }
        break;
    case OP_get_super_value:
        /* depth = 3 */
        switch(special) {
        case PUT_LVALUE_NOKEEP:
        case PUT_LVALUE_NOKEEP_DEPTH:
            break;
        case PUT_LVALUE_KEEP_TOP:
            emit_op(s, OP_insert4); /* this obj prop v -> v this obj prop v */
            break;
        case PUT_LVALUE_KEEP_SECOND:
            emit_op(s, OP_perm5); /* this obj prop v0 v -> v0 this obj prop v */
            break;
        case PUT_LVALUE_NOKEEP_BOTTOM:
            emit_op(s, OP_rot4l);
            break;
        default:
            abort();
        }
        break;
    default:
        break;
    }
    switch(opcode) {
    case OP_scope_get_var:  /* val -- */
        assert(special == PUT_LVALUE_NOKEEP ||
               special == PUT_LVALUE_NOKEEP_DEPTH);
        emit_op(s, is_let ? OP_scope_put_var_init : OP_scope_put_var);
        emit_u32(s, name);  /* has refcount */
        emit_u16(s, scope);
        break;
    case OP_get_field:
        emit_op(s, OP_put_field);
        emit_u32(s, name);  /* name has refcount */
        break;
    case OP_scope_get_private_field:
        emit_op(s, OP_scope_put_private_field);
        emit_u32(s, name);  /* name has refcount */
        emit_u16(s, scope);
        break;
    case OP_get_array_el:
        emit_op(s, OP_put_array_el);
        break;
    case OP_get_ref_value:
        emit_op(s, OP_put_ref_value);
        break;
    case OP_get_super_value:
        emit_op(s, OP_put_super_value);
        break;
    default:
        abort();
    }
}

static void js_emit_spread_code(JSParseState *s, int depth)
{
    int label_rest_next, label_rest_done;
    /* XXX: could check if enum object is an actual array and optimize
       slice extraction. enumeration record and target array are in a
       different order from OP_append case. */
    /* enum_rec xxx -- enum_rec xxx array 0 */
    emit_op(s, OP_array_from);
    emit_u16(s, 0);
    emit_op(s, OP_push_i32);
    emit_u32(s, 0);
    emit_label(s, label_rest_next = new_label(s));
    emit_op(s, OP_for_of_next);
    emit_u8(s, 2 + depth);
    label_rest_done = emit_goto(s, OP_if_true, -1);
    /* array idx val -- array idx */
    emit_op(s, OP_define_array_el);
    emit_op(s, OP_inc);
    emit_goto(s, OP_goto, label_rest_next);
    emit_label(s, label_rest_done);
    /* enum_rec xxx array idx undef -- enum_rec xxx array */
    emit_op(s, OP_drop);
    emit_op(s, OP_drop);
}

static void push_break_entry(JSFunctionDef *fd, BlockEnv *be,
                             JSAtom label_name,
                             int label_break, int label_cont,
                             int drop_count)
{
    be->prev = fd->top_break;
    fd->top_break = be;
    be->label_name = label_name;
    be->label_break = label_break;
    be->label_cont = label_cont;
    be->drop_count = drop_count;
    be->label_finally = -1;
    be->scope_level = fd->scope_level;
    be->has_iterator = FALSE;
}

static void pop_break_entry(JSFunctionDef *fd)
{
    BlockEnv *be;
    be = fd->top_break;
    fd->top_break = be->prev;
}

/* Return -1 if error, 0 if no initializer, 1 if an initializer is
   present at the top level. */
static int js_parse_destructuring_element(JSParseState *s, int tok, int is_arg,
                                          int hasval, int has_ellipsis,
                                          BOOL allow_initializer)
{
    int label_parse, label_assign, label_done, label_lvalue, depth_lvalue;
    int start_addr, assign_addr;
    JSAtom prop_name, var_name;
    int opcode, scope, tok1, skip_bits;
    BOOL has_initializer;
    if (has_ellipsis < 0) {
        /* pre-parse destructuration target for spread detection */
        js_parse_skip_parens_token(s, &skip_bits, FALSE);
        has_ellipsis = skip_bits & SKIP_HAS_ELLIPSIS;
    }
    label_parse = new_label(s);
    label_assign = new_label(s);
    start_addr = s->cur_func->byte_code.size;
    if (hasval) {
        /* consume value from the stack */
        emit_op(s, OP_dup);
        emit_op(s, OP_undefined);
        emit_op(s, OP_strict_eq);
        emit_goto(s, OP_if_true, label_parse);
        emit_label(s, label_assign);
    } else {
        emit_goto(s, OP_goto, label_parse);
        emit_label(s, label_assign);
        /* leave value on the stack */
        emit_op(s, OP_dup);
    }
    assign_addr = s->cur_func->byte_code.size;
    if (s->token.val == '{') {
        if (next_token(s))
            return -1;
        /* throw an exception if the value cannot be converted to an object */
        emit_op(s, OP_to_object);
        if (has_ellipsis) {
            /* add excludeList on stack just below src object */
            emit_op(s, OP_object);
            emit_op(s, OP_swap);
        }
        while (s->token.val != '}') {
            int prop_type;
            if (s->token.val == TOK_ELLIPSIS) {
                if (!has_ellipsis) {
                    JS_ThrowInternalError(s->ctx, "unexpected ellipsis token");
                    return -1;
                }
                if (next_token(s))
                    return -1;
                if (tok) {
                    var_name = js_parse_destructuring_var(s, tok, is_arg);
                    if (var_name == JS_ATOM_NULL)
                        return -1;
                    opcode = OP_scope_get_var;
                    scope = s->cur_func->scope_level;
                    label_lvalue = -1;
                    depth_lvalue = 0;
                } else {
                    if (js_parse_left_hand_side_expr(s))
                        return -1;
                    if (get_lvalue(s, &opcode, &scope, &var_name,
                                   &label_lvalue, &depth_lvalue, FALSE, '{'))
                        return -1;
                }
                if (s->token.val != '}') {
                    js_parse_error(s, "assignment rest property must be last");
                    goto var_error;
                }
                emit_op(s, OP_object);  /* target */
                emit_op(s, OP_copy_data_properties);
                emit_u8(s, 0 | ((depth_lvalue + 1) << 2) | ((depth_lvalue + 2) << 5));
                goto set_val;
            }
            prop_type = js_parse_property_name(s, &prop_name, FALSE, TRUE, FALSE);
            if (prop_type < 0)
                return -1;
            var_name = JS_ATOM_NULL;
            opcode = OP_scope_get_var;
            scope = s->cur_func->scope_level;
            label_lvalue = -1;
            depth_lvalue = 0;
            if (prop_type == PROP_TYPE_IDENT) {
                if (next_token(s))
                    goto prop_error;
                if ((s->token.val == '[' || s->token.val == '{')
                    &&  ((tok1 = js_parse_skip_parens_token(s, &skip_bits, FALSE)) == ',' ||
                         tok1 == '=' || tok1 == '}')) {
                    if (prop_name == JS_ATOM_NULL) {
                        /* computed property name on stack */
                        if (has_ellipsis) {
                            /* define the property in excludeList */
                            emit_op(s, OP_to_propkey); /* avoid calling ToString twice */
                            emit_op(s, OP_perm3); /* TOS: src excludeList prop */
                            emit_op(s, OP_null); /* TOS: src excludeList prop null */
                            emit_op(s, OP_define_array_el); /* TOS: src excludeList prop */
                            emit_op(s, OP_perm3); /* TOS: excludeList src prop */
                        }
                        /* get the computed property from the source object */
                        emit_op(s, OP_get_array_el2);
                    } else {
                        /* named property */
                        if (has_ellipsis) {
                            /* define the property in excludeList */
                            emit_op(s, OP_swap); /* TOS: src excludeList */
                            emit_op(s, OP_null); /* TOS: src excludeList null */
                            emit_op(s, OP_define_field); /* TOS: src excludeList */
                            emit_atom(s, prop_name);
                            emit_op(s, OP_swap); /* TOS: excludeList src */
                        }
                        /* get the named property from the source object */
                        emit_op(s, OP_get_field2);
                        emit_u32(s, prop_name);
                    }
                    if (js_parse_destructuring_element(s, tok, is_arg, TRUE, -1, TRUE) < 0)
                        return -1;
                    if (s->token.val == '}')
                        break;
                    /* accept a trailing comma before the '}' */
                    if (js_parse_expect(s, ','))
                        return -1;
                    continue;
                }
                if (prop_name == JS_ATOM_NULL) {
                    emit_op(s, OP_to_propkey2);
                    if (has_ellipsis) {
                        /* define the property in excludeList */
                        emit_op(s, OP_perm3);
                        emit_op(s, OP_null);
                        emit_op(s, OP_define_array_el);
                        emit_op(s, OP_perm3);
                    }
                    /* source prop -- source source prop */
                    emit_op(s, OP_dup1);
                } else {
                    if (has_ellipsis) {
                        /* define the property in excludeList */
                        emit_op(s, OP_swap);
                        emit_op(s, OP_null);
                        emit_op(s, OP_define_field);
                        emit_atom(s, prop_name);
                        emit_op(s, OP_swap);
                    }
                    /* source -- source source */
                    emit_op(s, OP_dup);
                }
                if (tok) {
                    var_name = js_parse_destructuring_var(s, tok, is_arg);
                    if (var_name == JS_ATOM_NULL)
                        goto prop_error;
                } else {
                    if (js_parse_left_hand_side_expr(s))
                        goto prop_error;
                lvalue:
                    if (get_lvalue(s, &opcode, &scope, &var_name,
                                   &label_lvalue, &depth_lvalue, FALSE, '{'))
                        goto prop_error;
                    /* swap ref and lvalue object if any */
                    if (prop_name == JS_ATOM_NULL) {
                        switch(depth_lvalue) {
                        case 1:
                            /* source prop x -> x source prop */
                            emit_op(s, OP_rot3r);
                            break;
                        case 2:
                            /* source prop x y -> x y source prop */
                            emit_op(s, OP_swap2);   /* t p2 s p1 */
                            break;
                        case 3:
                            /* source prop x y z -> x y z source prop */
                            emit_op(s, OP_rot5l);
                            emit_op(s, OP_rot5l);
                            break;
                        }
                    } else {
                        switch(depth_lvalue) {
                        case 1:
                            /* source x -> x source */
                            emit_op(s, OP_swap);
                            break;
                        case 2:
                            /* source x y -> x y source */
                            emit_op(s, OP_rot3l);
                            break;
                        case 3:
                            /* source x y z -> x y z source */
                            emit_op(s, OP_rot4l);
                            break;
                        }
                    }
                }
                if (prop_name == JS_ATOM_NULL) {
                    /* computed property name on stack */
                    /* XXX: should have OP_get_array_el2x with depth */
                    /* source prop -- val */
                    emit_op(s, OP_get_array_el);
                } else {
                    /* named property */
                    /* XXX: should have OP_get_field2x with depth */
                    /* source -- val */
                    emit_op(s, OP_get_field);
                    emit_u32(s, prop_name);
                }
            } else {
                /* prop_type = PROP_TYPE_VAR, cannot be a computed property */
                if (is_arg && js_parse_check_duplicate_parameter(s, prop_name))
                    goto prop_error;
                if ((s->cur_func->js_mode & JS_MODE_STRICT) &&
                    (prop_name == JS_ATOM_eval || prop_name == JS_ATOM_arguments)) {
                    js_parse_error(s, "invalid destructuring target");
                    goto prop_error;
                }
                if (has_ellipsis) {
                    /* define the property in excludeList */
                    emit_op(s, OP_swap);
                    emit_op(s, OP_null);
                    emit_op(s, OP_define_field);
                    emit_atom(s, prop_name);
                    emit_op(s, OP_swap);
                }
                if (!tok || tok == TOK_VAR) {
                    /* generate reference */
                    /* source -- source source */
                    emit_op(s, OP_dup);
                    emit_op(s, OP_scope_get_var);
                    emit_atom(s, prop_name);
                    emit_u16(s, s->cur_func->scope_level);
                    goto lvalue;
                }
                var_name = JS_DupAtom(s->ctx, prop_name);
                /* source -- source val */
                emit_op(s, OP_get_field2);
                emit_u32(s, prop_name);
            }
        set_val:
            if (tok) {
                if (js_define_var(s, var_name, tok))
                    goto var_error;
                scope = s->cur_func->scope_level;
            }
            if (s->token.val == '=') {  /* handle optional default value */
                int label_hasval;
                emit_op(s, OP_dup);
                emit_op(s, OP_undefined);
                emit_op(s, OP_strict_eq);
                label_hasval = emit_goto(s, OP_if_false, -1);
                if (next_token(s))
                    goto var_error;
                emit_op(s, OP_drop);
                if (js_parse_assign_expr(s))
                    goto var_error;
                if (opcode == OP_scope_get_var || opcode == OP_get_ref_value)
                    set_object_name(s, var_name);
                emit_label(s, label_hasval);
            }
            /* store value into lvalue object */
            put_lvalue(s, opcode, scope, var_name, label_lvalue,
                       PUT_LVALUE_NOKEEP_DEPTH,
                       (tok == TOK_CONST || tok == TOK_LET));
            if (s->token.val == '}')
                break;
            /* accept a trailing comma before the '}' */
            if (js_parse_expect(s, ','))
                return -1;
        }
        /* drop the source object */
        emit_op(s, OP_drop);
        if (has_ellipsis) {
            emit_op(s, OP_drop); /* pop excludeList */
        }
        if (next_token(s))
            return -1;
    } else if (s->token.val == '[') {
        BOOL has_spread;
        int enum_depth;
        BlockEnv block_env;
        if (next_token(s))
            return -1;
        /* the block environment is only needed in generators in case
           'yield' triggers a 'return' */
        push_break_entry(s->cur_func, &block_env,
                         JS_ATOM_NULL, -1, -1, 2);
        block_env.has_iterator = TRUE;
        emit_op(s, OP_for_of_start);
        has_spread = FALSE;
        while (s->token.val != ']') {
            /* get the next value */
            if (s->token.val == TOK_ELLIPSIS) {
                if (next_token(s))
                    return -1;
                if (s->token.val == ',' || s->token.val == ']')
                    return js_parse_error(s, "missing binding pattern...");
                has_spread = TRUE;
            }
            if (s->token.val == ',') {
                /* do nothing, skip the value, has_spread is false */
                emit_op(s, OP_for_of_next);
                emit_u8(s, 0);
                emit_op(s, OP_drop);
                emit_op(s, OP_drop);
            } else if ((s->token.val == '[' || s->token.val == '{')
                   &&  ((tok1 = js_parse_skip_parens_token(s, &skip_bits, FALSE)) == ',' ||
                        tok1 == '=' || tok1 == ']')) {
                if (has_spread) {
                    if (tok1 == '=')
                        return js_parse_error(s, "rest element cannot have a default value");
                    js_emit_spread_code(s, 0);
                } else {
                    emit_op(s, OP_for_of_next);
                    emit_u8(s, 0);
                    emit_op(s, OP_drop);
                }
                if (js_parse_destructuring_element(s, tok, is_arg, TRUE, skip_bits & SKIP_HAS_ELLIPSIS, TRUE) < 0)
                    return -1;
            } else {
                var_name = JS_ATOM_NULL;
                enum_depth = 0;
                if (tok) {
                    var_name = js_parse_destructuring_var(s, tok, is_arg);
                    if (var_name == JS_ATOM_NULL)
                        goto var_error;
                    if (js_define_var(s, var_name, tok))
                        goto var_error;
                    opcode = OP_scope_get_var;
                    scope = s->cur_func->scope_level;
                } else {
                    if (js_parse_left_hand_side_expr(s))
                        return -1;
                    if (get_lvalue(s, &opcode, &scope, &var_name,
                                   &label_lvalue, &enum_depth, FALSE, '[')) {
                        return -1;
                    }
                }
                if (has_spread) {
                    js_emit_spread_code(s, enum_depth);
                } else {
                    emit_op(s, OP_for_of_next);
                    emit_u8(s, enum_depth);
                    emit_op(s, OP_drop);
                }
                if (s->token.val == '=' && !has_spread) {
                    /* handle optional default value */
                    int label_hasval;
                    emit_op(s, OP_dup);
                    emit_op(s, OP_undefined);
                    emit_op(s, OP_strict_eq);
                    label_hasval = emit_goto(s, OP_if_false, -1);
                    if (next_token(s))
                        goto var_error;
                    emit_op(s, OP_drop);
                    if (js_parse_assign_expr(s))
                        goto var_error;
                    if (opcode == OP_scope_get_var || opcode == OP_get_ref_value)
                        set_object_name(s, var_name);
                    emit_label(s, label_hasval);
                }
                /* store value into lvalue object */
                put_lvalue(s, opcode, scope, var_name,
                           label_lvalue, PUT_LVALUE_NOKEEP_DEPTH,
                           (tok == TOK_CONST || tok == TOK_LET));
            }
            if (s->token.val == ']')
                break;
            if (has_spread)
                return js_parse_error(s, "rest element must be the last one");
            /* accept a trailing comma before the ']' */
            if (js_parse_expect(s, ','))
                return -1;
        }
        /* close iterator object:
           if completed, enum_obj has been replaced by undefined */
        emit_op(s, OP_iterator_close);
        pop_break_entry(s->cur_func);
        if (next_token(s))
            return -1;
    } else {
        return js_parse_error(s, "invalid assignment syntax");
    }
    if (s->token.val == '=' && allow_initializer) {
        label_done = emit_goto(s, OP_goto, -1);
        if (next_token(s))
            return -1;
        emit_label(s, label_parse);
        if (hasval)
            emit_op(s, OP_drop);
        if (js_parse_assign_expr(s))
            return -1;
        emit_goto(s, OP_goto, label_assign);
        emit_label(s, label_done);
        has_initializer = TRUE;
    } else {
        /* normally hasval is true except if
           js_parse_skip_parens_token() was wrong in the parsing */
        //        assert(hasval);
        if (!hasval) {
            js_parse_error(s, "too complicated destructuring expression");
            return -1;
        }
        /* remove test and decrement label ref count */
        memset(s->cur_func->byte_code.buf + start_addr, OP_nop,
               assign_addr - start_addr);
        s->cur_func->label_slots[label_parse].ref_count--;
        has_initializer = FALSE;
    }
    return has_initializer;
 prop_error:
    JS_FreeAtom(s->ctx, prop_name);
 var_error:
    JS_FreeAtom(s->ctx, var_name);
    return -1;
}

static __exception int js_parse_array_literal(JSParseState *s)
{
    uint32_t idx;
    BOOL need_length;
    if (next_token(s))
        return -1;
    /* small regular arrays are created on the stack */
    idx = 0;
    while (s->token.val != ']' && idx < 32) {
        if (s->token.val == ',' || s->token.val == TOK_ELLIPSIS)
            break;
        if (js_parse_assign_expr(s))
            return -1;
        idx++;
        /* accept trailing comma */
        if (s->token.val == ',') {
            if (next_token(s))
                return -1;
        } else
        if (s->token.val != ']')
            goto done;
    }
    emit_op(s, OP_array_from);
    emit_u16(s, idx);
    /* larger arrays and holes are handled with explicit indices */
    need_length = FALSE;
    while (s->token.val != ']' && idx < 0x7fffffff) {
        if (s->token.val == TOK_ELLIPSIS)
            break;
        need_length = TRUE;
        if (s->token.val != ',') {
            if (js_parse_assign_expr(s))
                return -1;
            emit_op(s, OP_define_field);
            emit_u32(s, __JS_AtomFromUInt32(idx));
            need_length = FALSE;
        }
        idx++;
        /* accept trailing comma */
        if (s->token.val == ',') {
            if (next_token(s))
                return -1;
        }
    }
    if (s->token.val == ']') {
        if (need_length) {
            /* Set the length: Cannot use OP_define_field because
               length is not configurable */
            emit_op(s, OP_dup);
            emit_op(s, OP_push_i32);
            emit_u32(s, idx);
            emit_op(s, OP_put_field);
            emit_atom(s, JS_ATOM_length);
        }
        goto done;
    }
    /* huge arrays and spread elements require a dynamic index on the stack */
    emit_op(s, OP_push_i32);
    emit_u32(s, idx);
    /* stack has array, index */
    while (s->token.val != ']') {
        if (s->token.val == TOK_ELLIPSIS) {
            if (next_token(s))
                return -1;
            if (js_parse_assign_expr(s))
                return -1;
#if 1
            emit_op(s, OP_append);
#else
            int label_next, label_done;
            label_next = new_label(s);
            label_done = new_label(s);
            /* enumerate object */
            emit_op(s, OP_for_of_start);
            emit_op(s, OP_rot5l);
            emit_op(s, OP_rot5l);
            emit_label(s, label_next);
            /* on stack: enum_rec array idx */
            emit_op(s, OP_for_of_next);
            emit_u8(s, 2);
            emit_goto(s, OP_if_true, label_done);
            /* append element */
            /* enum_rec array idx val -> enum_rec array new_idx */
            emit_op(s, OP_define_array_el);
            emit_op(s, OP_inc);
            emit_goto(s, OP_goto, label_next);
            emit_label(s, label_done);
            /* close enumeration */
            emit_op(s, OP_drop); /* drop undef val */
            emit_op(s, OP_nip1); /* drop enum_rec */
            emit_op(s, OP_nip1);
            emit_op(s, OP_nip1);
#endif
        } else {
            need_length = TRUE;
            if (s->token.val != ',') {
                if (js_parse_assign_expr(s))
                    return -1;
                /* a idx val */
                emit_op(s, OP_define_array_el);
                need_length = FALSE;
            }
            emit_op(s, OP_inc);
        }
        if (s->token.val != ',')
            break;
        if (next_token(s))
            return -1;
    }
    if (need_length) {
        /* Set the length: cannot use OP_define_field because
           length is not configurable */
        emit_op(s, OP_dup1);    /* array length - array array length */
        emit_op(s, OP_put_field);
        emit_atom(s, JS_ATOM_length);
    } else {
        emit_op(s, OP_drop);    /* array length - array */
    }
done:
    return js_parse_expect(s, ']');
}

/* XXX: remove */
static BOOL has_with_scope(JSFunctionDef *s, int scope_level)
{
    /* check if scope chain contains a with statement */
    while (s) {
        int scope_idx = s->scopes[scope_level].first;
        while (scope_idx >= 0) {
            JSVarDef *vd = &s->vars[scope_idx];
            if (vd->var_name == JS_ATOM__with_)
                return TRUE;
            scope_idx = vd->scope_next;
        }
        /* check parent scopes */
        scope_level = s->parent_scope_level;
        s = s->parent;
    }
    return FALSE;
}

static void optional_chain_test(JSParseState *s, int *poptional_chaining_label,
                                int drop_count)
{
    int label_next, i;
    if (*poptional_chaining_label < 0)
        *poptional_chaining_label = new_label(s);
   /* XXX: could be more efficient with a specific opcode */
    emit_op(s, OP_dup);
    emit_op(s, OP_is_undefined_or_null);
    label_next = emit_goto(s, OP_if_false, -1);
    for(i = 0; i < drop_count; i++)
        emit_op(s, OP_drop);
    emit_op(s, OP_undefined);
    emit_goto(s, OP_goto, *poptional_chaining_label);
    emit_label(s, label_next);
}

/* initialize the class fields, called by the constructor. Note:
   super() can be called in an arrow function, so <this> and
   <class_fields_init> can be variable references */
static void emit_class_field_init(JSParseState *s)
{
    int label_next;
    emit_op(s, OP_scope_get_var);
    emit_atom(s, JS_ATOM_class_fields_init);
    emit_u16(s, s->cur_func->scope_level);
    /* no need to call the class field initializer if not defined */
    emit_op(s, OP_dup);
    label_next = emit_goto(s, OP_if_false, -1);
    emit_op(s, OP_scope_get_var);
    emit_atom(s, JS_ATOM_this);
    emit_u16(s, 0);
    emit_op(s, OP_swap);
    emit_op(s, OP_call_method);
    emit_u16(s, 0);
    emit_label(s, label_next);
    emit_op(s, OP_drop);
}

/* allowed parse_flags: PF_POSTFIX_CALL, PF_ARROW_FUNC */
static __exception int js_parse_postfix_expr(JSParseState *s, int parse_flags)
{
    FuncCallType call_type;
    int optional_chaining_label;
    BOOL accept_lparen = (parse_flags & PF_POSTFIX_CALL) != 0;
    call_type = FUNC_CALL_NORMAL;
    switch(s->token.val) {
    case TOK_NUMBER:
        {
            JSValue val;
            val = s->token.u.num.val;
            if (JS_VALUE_GET_TAG(val) == JS_TAG_INT) {
                emit_op(s, OP_push_i32);
                emit_u32(s, JS_VALUE_GET_INT(val));
            } else
#ifdef CONFIG_BIGNUM
            if (JS_VALUE_GET_TAG(val) == JS_TAG_BIG_FLOAT) {
                slimb_t e;
                int ret;
                /* need a runtime conversion */
                /* XXX: could add a cache and/or do it once at
                   the start of the function */
                if (emit_push_const(s, val, 0) < 0)
                    return -1;
                e = s->token.u.num.exponent;
                if (e == (int32_t)e) {
                    emit_op(s, OP_push_i32);
                    emit_u32(s, e);
                } else {
                    val = JS_NewBigInt64_1(s->ctx, e);
                    if (JS_IsException(val))
                        return -1;
                    ret = emit_push_const(s, val, 0);
                    JS_FreeValue(s->ctx, val);
                    if (ret < 0)
                        return -1;
                }
                emit_op(s, OP_mul_pow10);
            } else
#endif
            {
                if (emit_push_const(s, val, 0) < 0)
                    return -1;
            }
        }
        if (next_token(s))
            return -1;
        break;
    case TOK_TEMPLATE:
        if (js_parse_template(s, 0, NULL))
            return -1;
        break;
    case TOK_STRING:
        if (emit_push_const(s, s->token.u.str.str, 1))
            return -1;
        if (next_token(s))
            return -1;
        break;
    case TOK_DIV_ASSIGN:
        s->buf_ptr -= 2;
        goto parse_regexp;
    case '/':
        s->buf_ptr--;
    parse_regexp:
        {
            JSValue str;
            int ret, backtrace_flags;
            if (!s->ctx->compile_regexp)
                return js_parse_error(s, "RegExp are not supported");
            /* the previous token is '/' or '/=', so no need to free */
            if (js_parse_regexp(s))
                return -1;
            ret = emit_push_const(s, s->token.u.regexp.body, 0);
            str = s->ctx->compile_regexp(s->ctx, s->token.u.regexp.body,
                                         s->token.u.regexp.flags);
            if (JS_IsException(str)) {
                /* add the line number info */
                backtrace_flags = 0;
                if (s->cur_func && s->cur_func->backtrace_barrier)
                    backtrace_flags = JS_BACKTRACE_FLAG_SINGLE_LEVEL;
                build_backtrace(s->ctx, s->ctx->rt->current_exception,
                                s->filename, s->token.line_num,
                                backtrace_flags);
                return -1;
            }
            ret = emit_push_const(s, str, 0);
            JS_FreeValue(s->ctx, str);
            if (ret)
                return -1;
            /* we use a specific opcode to be sure the correct
               function is called (otherwise the bytecode would have
               to be verified by the RegExp constructor) */
            emit_op(s, OP_regexp);
            if (next_token(s))
                return -1;
        }
        break;
    case '(':
        if ((parse_flags & PF_ARROW_FUNC) &&
            js_parse_skip_parens_token(s, NULL, TRUE) == TOK_ARROW) {
            if (js_parse_function_decl(s, JS_PARSE_FUNC_ARROW,
                                       JS_FUNC_NORMAL, JS_ATOM_NULL,
                                       s->token.ptr, s->token.line_num))
                return -1;
        } else {
            if (js_parse_expr_paren(s))
                return -1;
        }
        break;
    case TOK_FUNCTION:
        if (js_parse_function_decl(s, JS_PARSE_FUNC_EXPR,
                                   JS_FUNC_NORMAL, JS_ATOM_NULL,
                                   s->token.ptr, s->token.line_num))
            return -1;
        break;
    case TOK_CLASS:
        if (js_parse_class(s, TRUE, JS_PARSE_EXPORT_NONE))
            return -1;
        break;
    case TOK_NULL:
        if (next_token(s))
            return -1;
        emit_op(s, OP_null);
        break;
    case TOK_THIS:
        if (next_token(s))
            return -1;
        emit_op(s, OP_scope_get_var);
        emit_atom(s, JS_ATOM_this);
        emit_u16(s, 0);
        break;
    case TOK_FALSE:
        if (next_token(s))
            return -1;
        emit_op(s, OP_push_false);
        break;
    case TOK_TRUE:
        if (next_token(s))
            return -1;
        emit_op(s, OP_push_true);
        break;
    case TOK_IDENT:
        {
            JSAtom name;
            if (s->token.u.ident.is_reserved) {
                return js_parse_error_reserved_identifier(s);
            }
            if ((parse_flags & PF_ARROW_FUNC) &&
                peek_token(s, TRUE) == TOK_ARROW) {
                if (js_parse_function_decl(s, JS_PARSE_FUNC_ARROW,
                                           JS_FUNC_NORMAL, JS_ATOM_NULL,
                                           s->token.ptr, s->token.line_num))
                    return -1;
            } else if (token_is_pseudo_keyword(s, JS_ATOM_async) &&
                       peek_token(s, TRUE) != '\n') {
                const uint8_t *source_ptr;
                int source_line_num;
                source_ptr = s->token.ptr;
                source_line_num = s->token.line_num;
                if (next_token(s))
                    return -1;
                if (s->token.val == TOK_FUNCTION) {
                    if (js_parse_function_decl(s, JS_PARSE_FUNC_EXPR,
                                               JS_FUNC_ASYNC, JS_ATOM_NULL,
                                               source_ptr, source_line_num))
                        return -1;
                } else if ((parse_flags & PF_ARROW_FUNC) &&
                           ((s->token.val == '(' &&
                             js_parse_skip_parens_token(s, NULL, TRUE) == TOK_ARROW) ||
                            (s->token.val == TOK_IDENT && !s->token.u.ident.is_reserved &&
                             peek_token(s, TRUE) == TOK_ARROW))) {
                    if (js_parse_function_decl(s, JS_PARSE_FUNC_ARROW,
                                               JS_FUNC_ASYNC, JS_ATOM_NULL,
                                               source_ptr, source_line_num))
                        return -1;
                } else {
                    name = JS_DupAtom(s->ctx, JS_ATOM_async);
                    goto do_get_var;
                }
            } else {
                if (s->token.u.ident.atom == JS_ATOM_arguments &&
                    !s->cur_func->arguments_allowed) {
                    js_parse_error(s, "'arguments' identifier is not allowed in class field initializer");
                    return -1;
                }
                name = JS_DupAtom(s->ctx, s->token.u.ident.atom);
                if (next_token(s))  /* update line number before emitting code */
                    return -1;
            do_get_var:
                emit_op(s, OP_scope_get_var);
                emit_u32(s, name);
                emit_u16(s, s->cur_func->scope_level);
            }
        }
        break;
    case '{':
    case '[':
        {
            int skip_bits;
            if (js_parse_skip_parens_token(s, &skip_bits, FALSE) == '=') {
                if (js_parse_destructuring_element(s, 0, 0, FALSE, skip_bits & SKIP_HAS_ELLIPSIS, TRUE) < 0)
                    return -1;
            } else {
                if (s->token.val == '{') {
                    if (js_parse_object_literal(s))
                        return -1;
                } else {
                    if (js_parse_array_literal(s))
                        return -1;
                }
            }
        }
        break;
    case TOK_NEW:
        if (next_token(s))
            return -1;
        if (s->token.val == '.') {
            if (next_token(s))
                return -1;
            if (!token_is_pseudo_keyword(s, JS_ATOM_target))
                return js_parse_error(s, "expecting target");
            if (!s->cur_func->new_target_allowed)
                return js_parse_error(s, "new.target only allowed within functions");
            if (next_token(s))
                return -1;
            emit_op(s, OP_scope_get_var);
            emit_atom(s, JS_ATOM_new_target);
            emit_u16(s, 0);
        } else {
            if (js_parse_postfix_expr(s, 0))
                return -1;
            accept_lparen = TRUE;
            if (s->token.val != '(') {
                /* new operator on an object */
                emit_op(s, OP_dup);
                emit_op(s, OP_call_constructor);
                emit_u16(s, 0);
            } else {
                call_type = FUNC_CALL_NEW;
            }
        }
        break;
    case TOK_SUPER:
        if (next_token(s))
            return -1;
        if (s->token.val == '(') {
            if (!s->cur_func->super_call_allowed)
                return js_parse_error(s, "super() is only valid in a derived class constructor");
            call_type = FUNC_CALL_SUPER_CTOR;
        } else if (s->token.val == '.' || s->token.val == '[') {
            if (!s->cur_func->super_allowed)
                return js_parse_error(s, "'super' is only valid in a method");
            emit_op(s, OP_scope_get_var);
            emit_atom(s, JS_ATOM_this);
            emit_u16(s, 0);
            emit_op(s, OP_scope_get_var);
            emit_atom(s, JS_ATOM_home_object);
            emit_u16(s, 0);
            emit_op(s, OP_get_super);
        } else {
            return js_parse_error(s, "invalid use of 'super'");
        }
        break;
    case TOK_IMPORT:
        if (next_token(s))
            return -1;
        if (s->token.val == '.') {
            if (next_token(s))
                return -1;
            if (!token_is_pseudo_keyword(s, JS_ATOM_meta))
                return js_parse_error(s, "meta expected");
            if (!s->is_module)
                return js_parse_error(s, "import.meta only valid in module code");
            if (next_token(s))
                return -1;
            emit_op(s, OP_special_object);
            emit_u8(s, OP_SPECIAL_OBJECT_IMPORT_META);
        } else {
            if (js_parse_expect(s, '('))
                return -1;
            if (!accept_lparen)
                return js_parse_error(s, "invalid use of 'import()'");
            if (js_parse_assign_expr(s))
                return -1;
            if (js_parse_expect(s, ')'))
                return -1;
            emit_op(s, OP_import);
        }
        break;
    default:
        return js_parse_error(s, "unexpected token in expression: '%.*s'",
                              (int)(s->buf_ptr - s->token.ptr), s->token.ptr);
    }
    optional_chaining_label = -1;
    for(;;) {
        JSFunctionDef *fd = s->cur_func;
        BOOL has_optional_chain = FALSE;
        if (s->token.val == TOK_QUESTION_MARK_DOT) {
            /* optional chaining */
            if (next_token(s))
                return -1;
            has_optional_chain = TRUE;
            if (s->token.val == '(' && accept_lparen) {
                goto parse_func_call;
            } else if (s->token.val == '[') {
                goto parse_array_access;
            } else {
                goto parse_property;
            }
        } else if (s->token.val == TOK_TEMPLATE &&
                   call_type == FUNC_CALL_NORMAL) {
            if (optional_chaining_label >= 0) {
                return js_parse_error(s, "template literal cannot appear in an optional chain");
            }
            call_type = FUNC_CALL_TEMPLATE;
            goto parse_func_call2;
        } else if (s->token.val == '(' && accept_lparen) {
            int opcode, arg_count, drop_count;
            /* function call */
        parse_func_call:
            if (next_token(s))
                return -1;
            if (call_type == FUNC_CALL_NORMAL) {
            parse_func_call2:
                switch(opcode = get_prev_opcode(fd)) {
                case OP_get_field:
                    /* keep the object on the stack */
                    fd->byte_code.buf[fd->last_opcode_pos] = OP_get_field2;
                    drop_count = 2;
                    break;
                case OP_scope_get_private_field:
                    /* keep the object on the stack */
                    fd->byte_code.buf[fd->last_opcode_pos] = OP_scope_get_private_field2;
                    drop_count = 2;
                    break;
                case OP_get_array_el:
                    /* keep the object on the stack */
                    fd->byte_code.buf[fd->last_opcode_pos] = OP_get_array_el2;
                    drop_count = 2;
                    break;
                case OP_scope_get_var:
                    {
                        JSAtom name;
                        int scope;
                        name = get_u32(fd->byte_code.buf + fd->last_opcode_pos + 1);
                        scope = get_u16(fd->byte_code.buf + fd->last_opcode_pos + 5);
                        if (name == JS_ATOM_eval && call_type == FUNC_CALL_NORMAL && !has_optional_chain) {
                            /* direct 'eval' */
                            opcode = OP_eval;
                        } else {
                            /* verify if function name resolves to a simple
                               get_loc/get_arg: a function call inside a `with`
                               statement can resolve to a method call of the
                               `with` context object
                             */
                            /* XXX: always generate the OP_scope_get_ref
                               and remove it in variable resolution
                               pass ? */
                            if (has_with_scope(fd, scope)) {
                                opcode = OP_scope_get_ref;
                                fd->byte_code.buf[fd->last_opcode_pos] = opcode;
                            }
                        }
                        drop_count = 1;
                    }
                    break;
                case OP_get_super_value:
                    fd->byte_code.buf[fd->last_opcode_pos] = OP_get_array_el;
                    /* on stack: this func_obj */
                    opcode = OP_get_array_el;
                    drop_count = 2;
                    break;
                default:
                    opcode = OP_invalid;
                    drop_count = 1;
                    break;
                }
                if (has_optional_chain) {
                    optional_chain_test(s, &optional_chaining_label,
                                        drop_count);
                }
            } else {
                opcode = OP_invalid;
            }
            if (call_type == FUNC_CALL_TEMPLATE) {
                if (js_parse_template(s, 1, &arg_count))
                    return -1;
                goto emit_func_call;
            } else if (call_type == FUNC_CALL_SUPER_CTOR) {
                emit_op(s, OP_scope_get_var);
                emit_atom(s, JS_ATOM_this_active_func);
                emit_u16(s, 0);
                emit_op(s, OP_get_super);
                emit_op(s, OP_scope_get_var);
                emit_atom(s, JS_ATOM_new_target);
                emit_u16(s, 0);
            } else if (call_type == FUNC_CALL_NEW) {
                emit_op(s, OP_dup); /* new.target = function */
            }
            /* parse arguments */
            arg_count = 0;
            while (s->token.val != ')') {
                if (arg_count >= 65535) {
                    return js_parse_error(s, "Too many call arguments");
                }
                if (s->token.val == TOK_ELLIPSIS)
                    break;
                if (js_parse_assign_expr(s))
                    return -1;
                arg_count++;
                if (s->token.val == ')')
                    break;
                /* accept a trailing comma before the ')' */
                if (js_parse_expect(s, ','))
                    return -1;
            }
            if (s->token.val == TOK_ELLIPSIS) {
                emit_op(s, OP_array_from);
                emit_u16(s, arg_count);
                emit_op(s, OP_push_i32);
                emit_u32(s, arg_count);
                /* on stack: array idx */
                while (s->token.val != ')') {
                    if (s->token.val == TOK_ELLIPSIS) {
                        if (next_token(s))
                            return -1;
                        if (js_parse_assign_expr(s))
                            return -1;
#if 1
                        /* XXX: could pass is_last indicator? */
                        emit_op(s, OP_append);
#else
                        int label_next, label_done;
                        label_next = new_label(s);
                        label_done = new_label(s);
                        /* push enumerate object below array/idx pair */
                        emit_op(s, OP_for_of_start);
                        emit_op(s, OP_rot5l);
                        emit_op(s, OP_rot5l);
                        emit_label(s, label_next);
                        /* on stack: enum_rec array idx */
                        emit_op(s, OP_for_of_next);
                        emit_u8(s, 2);
                        emit_goto(s, OP_if_true, label_done);
                        /* append element */
                        /* enum_rec array idx val -> enum_rec array new_idx */
                        emit_op(s, OP_define_array_el);
                        emit_op(s, OP_inc);
                        emit_goto(s, OP_goto, label_next);
                        emit_label(s, label_done);
                        /* close enumeration, drop enum_rec and idx */
                        emit_op(s, OP_drop); /* drop undef */
                        emit_op(s, OP_nip1); /* drop enum_rec */
                        emit_op(s, OP_nip1);
                        emit_op(s, OP_nip1);
#endif
                    } else {
                        if (js_parse_assign_expr(s))
                            return -1;
                        /* array idx val */
                        emit_op(s, OP_define_array_el);
                        emit_op(s, OP_inc);
                    }
                    if (s->token.val == ')')
                        break;
                    /* accept a trailing comma before the ')' */
                    if (js_parse_expect(s, ','))
                        return -1;
                }
                if (next_token(s))
                    return -1;
                /* drop the index */
                emit_op(s, OP_drop);
                /* apply function call */
                switch(opcode) {
                case OP_get_field:
                case OP_scope_get_private_field:
                case OP_get_array_el:
                case OP_scope_get_ref:
                    /* obj func array -> func obj array */
                    emit_op(s, OP_perm3);
                    emit_op(s, OP_apply);
                    emit_u16(s, call_type == FUNC_CALL_NEW);
                    break;
                case OP_eval:
                    emit_op(s, OP_apply_eval);
                    emit_u16(s, fd->scope_level);
                    fd->has_eval_call = TRUE;
                    break;
                default:
                    if (call_type == FUNC_CALL_SUPER_CTOR) {
                        emit_op(s, OP_apply);
                        emit_u16(s, 1);
                        /* set the 'this' value */
                        emit_op(s, OP_dup);
                        emit_op(s, OP_scope_put_var_init);
                        emit_atom(s, JS_ATOM_this);
                        emit_u16(s, 0);
                        emit_class_field_init(s);
                    } else if (call_type == FUNC_CALL_NEW) {
                        /* obj func array -> func obj array */
                        emit_op(s, OP_perm3);
                        emit_op(s, OP_apply);
                        emit_u16(s, 1);
                    } else {
                        /* func array -> func undef array */
                        emit_op(s, OP_undefined);
                        emit_op(s, OP_swap);
                        emit_op(s, OP_apply);
                        emit_u16(s, 0);
                    }
                    break;
                }
            } else {
                if (next_token(s))
                    return -1;
            emit_func_call:
                switch(opcode) {
                case OP_get_field:
                case OP_scope_get_private_field:
                case OP_get_array_el:
                case OP_scope_get_ref:
                    emit_op(s, OP_call_method);
                    emit_u16(s, arg_count);
                    break;
                case OP_eval:
                    emit_op(s, OP_eval);
                    emit_u16(s, arg_count);
                    emit_u16(s, fd->scope_level);
                    fd->has_eval_call = TRUE;
                    break;
                default:
                    if (call_type == FUNC_CALL_SUPER_CTOR) {
                        emit_op(s, OP_call_constructor);
                        emit_u16(s, arg_count);
                        /* set the 'this' value */
                        emit_op(s, OP_dup);
                        emit_op(s, OP_scope_put_var_init);
                        emit_atom(s, JS_ATOM_this);
                        emit_u16(s, 0);
                        emit_class_field_init(s);
                    } else if (call_type == FUNC_CALL_NEW) {
                        emit_op(s, OP_call_constructor);
                        emit_u16(s, arg_count);
                    } else {
                        emit_op(s, OP_call);
                        emit_u16(s, arg_count);
                    }
                    break;
                }
            }
            call_type = FUNC_CALL_NORMAL;
        } else if (s->token.val == '.') {
            if (next_token(s))
                return -1;
        parse_property:
            if (s->token.val == TOK_PRIVATE_NAME) {
                /* private class field */
                if (get_prev_opcode(fd) == OP_get_super) {
                    return js_parse_error(s, "private class field forbidden after super");
                }
                if (has_optional_chain) {
                    optional_chain_test(s, &optional_chaining_label, 1);
                }
                emit_op(s, OP_scope_get_private_field);
                emit_atom(s, s->token.u.ident.atom);
                emit_u16(s, s->cur_func->scope_level);
            } else {
                if (!token_is_ident(s->token.val)) {
                    return js_parse_error(s, "expecting field name");
                }
                if (get_prev_opcode(fd) == OP_get_super) {
                    JSValue val;
                    int ret;
                    val = JS_AtomToValue(s->ctx, s->token.u.ident.atom);
                    ret = emit_push_const(s, val, 1);
                    JS_FreeValue(s->ctx, val);
                    if (ret)
                        return -1;
                    emit_op(s, OP_get_super_value);
                } else {
                    if (has_optional_chain) {
                        optional_chain_test(s, &optional_chaining_label, 1);
                    }
                    emit_op(s, OP_get_field);
                    emit_atom(s, s->token.u.ident.atom);
                }
            }
            if (next_token(s))
                return -1;
        } else if (s->token.val == '[') {
            int prev_op;
        parse_array_access:
            prev_op = get_prev_opcode(fd);
            if (has_optional_chain) {
                optional_chain_test(s, &optional_chaining_label, 1);
            }
            if (next_token(s))
                return -1;
            if (js_parse_expr(s))
                return -1;
            if (js_parse_expect(s, ']'))
                return -1;
            if (prev_op == OP_get_super) {
                emit_op(s, OP_get_super_value);
            } else {
                emit_op(s, OP_get_array_el);
            }
        } else {
            break;
        }
    }
    if (optional_chaining_label >= 0)
        emit_label(s, optional_chaining_label);
    return 0;
}

static int js_unsupported_keyword(JSParseState *s, JSAtom atom)
{
    char buf[ATOM_GET_STR_BUF_SIZE];
    return js_parse_error(s, "unsupported keyword: %s",
                          JS_AtomGetStr(s->ctx, buf, sizeof(buf), atom));
}

/* XXX: handle IteratorClose when exiting the loop before the
   enumeration is done */
static __exception int js_parse_for_in_of(JSParseState *s, int label_name,
                                          BOOL is_async)
{
    JSContext *ctx = s->ctx;
    JSFunctionDef *fd = s->cur_func;
    JSAtom var_name;
    BOOL has_initializer, is_for_of, has_destructuring;
    int tok, tok1, opcode, scope, block_scope_level;
    int label_next, label_expr, label_cont, label_body, label_break;
    int pos_next, pos_expr;
    BlockEnv break_entry;
    has_initializer = FALSE;
    has_destructuring = FALSE;
    is_for_of = FALSE;
    block_scope_level = fd->scope_level;
    label_cont = new_label(s);
    label_body = new_label(s);
    label_break = new_label(s);
    label_next = new_label(s);
    /* create scope for the lexical variables declared in the enumeration
       expressions. XXX: Not completely correct because of weird capturing
       semantics in `for (i of o) a.push(function(){return i})` */
    push_scope(s);
    /* local for_in scope starts here so individual elements
       can be closed in statement. */
    push_break_entry(s->cur_func, &break_entry,
                     label_name, label_break, label_cont, 1);
    break_entry.scope_level = block_scope_level;
    label_expr = emit_goto(s, OP_goto, -1);
    pos_next = s->cur_func->byte_code.size;
    emit_label(s, label_next);
    tok = s->token.val;
    switch (is_let(s, DECL_MASK_OTHER)) {
    case TRUE:
        tok = TOK_LET;
        break;
    case FALSE:
        break;
    default:
        return -1;
    }
    if (tok == TOK_VAR || tok == TOK_LET || tok == TOK_CONST) {
        if (next_token(s))
            return -1;
        if (!(s->token.val == TOK_IDENT && !s->token.u.ident.is_reserved)) {
            if (s->token.val == '[' || s->token.val == '{') {
                if (js_parse_destructuring_element(s, tok, 0, TRUE, -1, FALSE) < 0)
                    return -1;
                has_destructuring = TRUE;
            } else {
                return js_parse_error(s, "variable name expected");
            }
            var_name = JS_ATOM_NULL;
        } else {
            var_name = JS_DupAtom(ctx, s->token.u.ident.atom);
            if (next_token(s)) {
                JS_FreeAtom(s->ctx, var_name);
                return -1;
            }
            if (js_define_var(s, var_name, tok)) {
                JS_FreeAtom(s->ctx, var_name);
                return -1;
            }
            emit_op(s, (tok == TOK_CONST || tok == TOK_LET) ?
                    OP_scope_put_var_init : OP_scope_put_var);
            emit_atom(s, var_name);
            emit_u16(s, fd->scope_level);
        }
    } else {
        int skip_bits;
        if ((s->token.val == '[' || s->token.val == '{')
        &&  ((tok1 = js_parse_skip_parens_token(s, &skip_bits, FALSE)) == TOK_IN || tok1 == TOK_OF)) {
            if (js_parse_destructuring_element(s, 0, 0, TRUE, skip_bits & SKIP_HAS_ELLIPSIS, TRUE) < 0)
                return -1;
        } else {
            int lvalue_label;
            if (js_parse_left_hand_side_expr(s))
                return -1;
            if (get_lvalue(s, &opcode, &scope, &var_name, &lvalue_label,
                           NULL, FALSE, TOK_FOR))
                return -1;
            put_lvalue(s, opcode, scope, var_name, lvalue_label,
                       PUT_LVALUE_NOKEEP_BOTTOM, FALSE);
        }
        var_name = JS_ATOM_NULL;
    }
    emit_goto(s, OP_goto, label_body);
    pos_expr = s->cur_func->byte_code.size;
    emit_label(s, label_expr);
    if (s->token.val == '=') {
        /* XXX: potential scoping issue if inside `with` statement */
        has_initializer = TRUE;
        /* parse and evaluate initializer prior to evaluating the
           object (only used with "for in" with a non lexical variable
           in non strict mode */
        if (next_token(s) || js_parse_assign_expr2(s, 0)) {
            JS_FreeAtom(ctx, var_name);
            return -1;
        }
        if (var_name != JS_ATOM_NULL) {
            emit_op(s, OP_scope_put_var);
            emit_atom(s, var_name);
            emit_u16(s, fd->scope_level);
        }
    }
    JS_FreeAtom(ctx, var_name);
    if (token_is_pseudo_keyword(s, JS_ATOM_of)) {
        break_entry.has_iterator = is_for_of = TRUE;
        break_entry.drop_count += 2;
        if (has_initializer)
            goto initializer_error;
    } else if (s->token.val == TOK_IN) {
        if (is_async)
            return js_parse_error(s, "'for await' loop should be used with 'of'");
        if (has_initializer &&
            (tok != TOK_VAR || (fd->js_mode & JS_MODE_STRICT) ||
             has_destructuring)) {
        initializer_error:
            return js_parse_error(s, "a declaration in the head of a for-%s loop can't have an initializer",
                                  is_for_of ? "of" : "in");
        }
    } else {
        return js_parse_error(s, "expected 'of' or 'in' in for control expression");
    }
    if (next_token(s))
        return -1;
    if (is_for_of) {
        if (js_parse_assign_expr(s))
            return -1;
    } else {
        if (js_parse_expr(s))
            return -1;
    }
    /* close the scope after having evaluated the expression so that
       the TDZ values are in the closures */
    close_scopes(s, s->cur_func->scope_level, block_scope_level);
    if (is_for_of) {
        if (is_async)
            emit_op(s, OP_for_await_of_start);
        else
            emit_op(s, OP_for_of_start);
        /* on stack: enum_rec */
    } else {
        emit_op(s, OP_for_in_start);
        /* on stack: enum_obj */
    }
    emit_goto(s, OP_goto, label_cont);
    if (js_parse_expect(s, ')'))
        return -1;
    if (OPTIMIZE) {
        /* move the `next` code here */
        DynBuf *bc = &s->cur_func->byte_code;
        int chunk_size = pos_expr - pos_next;
        int offset = bc->size - pos_next;
        int i;
        dbuf_realloc(bc, bc->size + chunk_size);
        dbuf_put(bc, bc->buf + pos_next, chunk_size);
        memset(bc->buf + pos_next, OP_nop, chunk_size);
        /* `next` part ends with a goto */
        s->cur_func->last_opcode_pos = bc->size - 5;
        /* relocate labels */
        for (i = label_cont; i < s->cur_func->label_count; i++) {
            LabelSlot *ls = &s->cur_func->label_slots[i];
            if (ls->pos >= pos_next && ls->pos < pos_expr)
                ls->pos += offset;
        }
    }
    emit_label(s, label_body);
    if (js_parse_statement(s))
        return -1;
    close_scopes(s, s->cur_func->scope_level, block_scope_level);
    emit_label(s, label_cont);
    if (is_for_of) {
        if (is_async) {
            /* call the next method */
            /* stack: iter_obj next catch_offset */
            emit_op(s, OP_dup3);
            emit_op(s, OP_drop);
            emit_op(s, OP_call_method);
            emit_u16(s, 0);
            /* get the result of the promise */
            emit_op(s, OP_await);
            /* unwrap the value and done values */
            emit_op(s, OP_iterator_get_value_done);
        } else {
            emit_op(s, OP_for_of_next);
            emit_u8(s, 0);
        }
    } else {
        emit_op(s, OP_for_in_next);
    }
    /* on stack: enum_rec / enum_obj value bool */
    emit_goto(s, OP_if_false, label_next);
    /* drop the undefined value from for_xx_next */
    emit_op(s, OP_drop);
    emit_label(s, label_break);
    if (is_for_of) {
        /* close and drop enum_rec */
        emit_op(s, OP_iterator_close);
    } else {
        emit_op(s, OP_drop);
    }
    pop_break_entry(s->cur_func);
    pop_scope(s);
    return 0;
}

/* allowed parse_flags: PF_IN_ACCEPTED */
static __exception int js_parse_var(JSParseState *s, int parse_flags, int tok,
                                    BOOL export_flag)
{
    JSContext *ctx = s->ctx;
    JSFunctionDef *fd = s->cur_func;
    JSAtom name = JS_ATOM_NULL;
    for (;;) {
        if (s->token.val == TOK_IDENT) {
            if (s->token.u.ident.is_reserved) {
                return js_parse_error_reserved_identifier(s);
            }
            name = JS_DupAtom(ctx, s->token.u.ident.atom);
            if (name == JS_ATOM_let && (tok == TOK_LET || tok == TOK_CONST)) {
                js_parse_error(s, "'let' is not a valid lexical identifier");
                goto var_error;
            }
            if (next_token(s))
                goto var_error;
            if (js_define_var(s, name, tok))
                goto var_error;
            if (export_flag) {
                if (!add_export_entry(s, s->cur_func->module, name, name,
                                      JS_EXPORT_TYPE_LOCAL))
                    goto var_error;
            }
            if (s->token.val == '=') {
                if (next_token(s))
                    goto var_error;
                if (tok == TOK_VAR) {
                    /* Must make a reference for proper `with` semantics */
                    int opcode, scope, label;
                    JSAtom name1;
                    emit_op(s, OP_scope_get_var);
                    emit_atom(s, name);
                    emit_u16(s, fd->scope_level);
                    if (get_lvalue(s, &opcode, &scope, &name1, &label, NULL, FALSE, '=') < 0)
                        goto var_error;
                    if (js_parse_assign_expr2(s, parse_flags)) {
                        JS_FreeAtom(ctx, name1);
                        goto var_error;
                    }
                    set_object_name(s, name);
                    put_lvalue(s, opcode, scope, name1, label,
                               PUT_LVALUE_NOKEEP, FALSE);
                } else {
                    if (js_parse_assign_expr2(s, parse_flags))
                        goto var_error;
                    set_object_name(s, name);
                    emit_op(s, (tok == TOK_CONST || tok == TOK_LET) ?
                        OP_scope_put_var_init : OP_scope_put_var);
                    emit_atom(s, name);
                    emit_u16(s, fd->scope_level);
                }
            } else {
                if (tok == TOK_CONST) {
                    js_parse_error(s, "missing initializer for const variable");
                    goto var_error;
                }
                if (tok == TOK_LET) {
                    /* initialize lexical variable upon entering its scope */
                    emit_op(s, OP_undefined);
                    emit_op(s, OP_scope_put_var_init);
                    emit_atom(s, name);
                    emit_u16(s, fd->scope_level);
                }
            }
            JS_FreeAtom(ctx, name);
        } else {
            int skip_bits;
            if ((s->token.val == '[' || s->token.val == '{')
            &&  js_parse_skip_parens_token(s, &skip_bits, FALSE) == '=') {
                emit_op(s, OP_undefined);
                if (js_parse_destructuring_element(s, tok, 0, TRUE, skip_bits & SKIP_HAS_ELLIPSIS, TRUE) < 0)
                    return -1;
            } else {
                return js_parse_error(s, "variable name expected");
            }
        }
        if (s->token.val != ',')
            break;
        if (next_token(s))
            return -1;
    }
    return 0;
 var_error:
    JS_FreeAtom(ctx, name);
    return -1;
}

/* execute the finally blocks before return */
static void emit_return(JSParseState *s, BOOL hasval)
{
    BlockEnv *top;
    int drop_count;
    drop_count = 0;
    top = s->cur_func->top_break;
    while (top != NULL) {
        /* XXX: emit the appropriate OP_leave_scope opcodes? Probably not
           required as all local variables will be closed upon returning
           from JS_CallInternal, but not in the same order. */
        if (top->has_iterator) {
            /* with 'yield', the exact number of OP_drop to emit is
               unknown, so we use a specific operation to look for
               the catch offset */
            if (!hasval) {
                emit_op(s, OP_undefined);
                hasval = TRUE;
            }
            emit_op(s, OP_iterator_close_return);
            if (s->cur_func->func_kind == JS_FUNC_ASYNC_GENERATOR) {
                int label_next, label_next2;
                emit_op(s, OP_drop); /* catch offset */
                emit_op(s, OP_drop); /* next */
                emit_op(s, OP_get_field2);
                emit_atom(s, JS_ATOM_return);
                /* stack: iter_obj return_func */
                emit_op(s, OP_dup);
                emit_op(s, OP_is_undefined_or_null);
                label_next = emit_goto(s, OP_if_true, -1);
                emit_op(s, OP_call_method);
                emit_u16(s, 0);
                emit_op(s, OP_iterator_check_object);
                emit_op(s, OP_await);
                label_next2 = emit_goto(s, OP_goto, -1);
                emit_label(s, label_next);
                emit_op(s, OP_drop);
                emit_label(s, label_next2);
                emit_op(s, OP_drop);
            } else {
                emit_op(s, OP_iterator_close);
            }
            drop_count = -3;
        }
        drop_count += top->drop_count;
        if (top->label_finally != -1) {
            while(drop_count) {
                /* must keep the stack top if hasval */
                emit_op(s, hasval ? OP_nip : OP_drop);
                drop_count--;
            }
            if (!hasval) {
                /* must push return value to keep same stack size */
                emit_op(s, OP_undefined);
                hasval = TRUE;
            }
            emit_goto(s, OP_gosub, top->label_finally);
        }
        top = top->prev;
    }
    if (s->cur_func->is_derived_class_constructor) {
        int label_return;
        /* 'this' can be uninitialized, so it may be accessed only if
           the derived class constructor does not return an object */
        if (hasval) {
            emit_op(s, OP_check_ctor_return);
            label_return = emit_goto(s, OP_if_false, -1);
            emit_op(s, OP_drop);
        } else {
            label_return = -1;
        }
        /* XXX: if this is not initialized, should throw the
           ReferenceError in the caller realm */
        emit_op(s, OP_scope_get_var);
        emit_atom(s, JS_ATOM_this);
        emit_u16(s, 0);
        emit_label(s, label_return);
        emit_op(s, OP_return);
    } else if (s->cur_func->func_kind != JS_FUNC_NORMAL) {
        if (!hasval) {
            emit_op(s, OP_undefined);
        } else if (s->cur_func->func_kind == JS_FUNC_ASYNC_GENERATOR) {
            emit_op(s, OP_await);
        }
        emit_op(s, OP_return_async);
    } else {
        emit_op(s, hasval ? OP_return : OP_return_undef);
    }
}

static void set_eval_ret_undefined(JSParseState *s)
{
    if (s->cur_func->eval_ret_idx >= 0) {
        emit_op(s, OP_undefined);
        emit_op(s, OP_put_loc);
        emit_u16(s, s->cur_func->eval_ret_idx);
    }
}

/* allowed parse_flags: PF_IN_ACCEPTED */
static __exception int js_parse_expr2(JSParseState *s, int parse_flags)
{
    BOOL comma = FALSE;
    for(;;) {
        if (js_parse_assign_expr2(s, parse_flags))
            return -1;
        if (comma) {
            /* prevent get_lvalue from using the last expression
               as an lvalue. This also prevents the conversion of
               of get_var to get_ref for method lookup in function
               call inside `with` statement.
             */
            s->cur_func->last_opcode_pos = -1;
        }
        if (s->token.val != ',')
            break;
        comma = TRUE;
        if (next_token(s))
            return -1;
        emit_op(s, OP_drop);
    }
    return 0;
}

static __exception int emit_break(JSParseState *s, JSAtom name, int is_cont)
{
    BlockEnv *top;
    int i, scope_level;
    scope_level = s->cur_func->scope_level;
    top = s->cur_func->top_break;
    while (top != NULL) {
        close_scopes(s, scope_level, top->scope_level);
        scope_level = top->scope_level;
        if (is_cont &&
            top->label_cont != -1 &&
            (name == JS_ATOM_NULL || top->label_name == name)) {
            /* continue stays inside the same block */
            emit_goto(s, OP_goto, top->label_cont);
            return 0;
        }
        if (!is_cont &&
            top->label_break != -1 &&
            (name == JS_ATOM_NULL || top->label_name == name)) {
            emit_goto(s, OP_goto, top->label_break);
            return 0;
        }
        i = 0;
        if (top->has_iterator) {
            emit_op(s, OP_iterator_close);
            i += 3;
        }
        for(; i < top->drop_count; i++)
            emit_op(s, OP_drop);
        if (top->label_finally != -1) {
            /* must push dummy value to keep same stack depth */
            emit_op(s, OP_undefined);
            emit_goto(s, OP_gosub, top->label_finally);
            emit_op(s, OP_drop);
        }
        top = top->prev;
    }
    if (name == JS_ATOM_NULL) {
        if (is_cont)
            return js_parse_error(s, "continue must be inside loop");
        else
            return js_parse_error(s, "break must be inside loop or switch");
    } else {
        return js_parse_error(s, "break/continue label not found");
    }
}

static int js_parse_statement_or_decl(JSParseState *s, int decl_mask)
{
    JSContext *ctx = s->ctx;
    JSAtom label_name;
    int tok;
    /* specific label handling */
    /* XXX: support multiple labels on loop statements */
    label_name = JS_ATOM_NULL;
    if (is_label(s)) {
        BlockEnv *be;
        label_name = JS_DupAtom(ctx, s->token.u.ident.atom);
        for (be = s->cur_func->top_break; be; be = be->prev) {
            if (be->label_name == label_name) {
                js_parse_error(s, "duplicate label name");
                goto fail;
            }
        }
        if (next_token(s))
            goto fail;
        if (js_parse_expect(s, ':'))
            goto fail;
        if (s->token.val != TOK_FOR
        &&  s->token.val != TOK_DO
        &&  s->token.val != TOK_WHILE) {
            /* labelled regular statement */
            int label_break, mask;
            BlockEnv break_entry;
            label_break = new_label(s);
            push_break_entry(s->cur_func, &break_entry,
                             label_name, label_break, -1, 0);
            if (!(s->cur_func->js_mode & JS_MODE_STRICT) &&
                (decl_mask & DECL_MASK_FUNC_WITH_LABEL)) {
                mask = DECL_MASK_FUNC | DECL_MASK_FUNC_WITH_LABEL;
            } else {
                mask = 0;
            }
            if (js_parse_statement_or_decl(s, mask))
                goto fail;
            emit_label(s, label_break);
            pop_break_entry(s->cur_func);
            goto done;
        }
    }
    switch(tok = s->token.val) {
    case '{':
        if (js_parse_block(s))
            goto fail;
        break;
    case TOK_RETURN:
        if (s->cur_func->is_eval) {
            js_parse_error(s, "return not in a function");
            goto fail;
        }
        if (next_token(s))
            goto fail;
        if (s->token.val != ';' && s->token.val != '}' && !s->got_lf) {
            if (js_parse_expr(s))
                goto fail;
            emit_return(s, TRUE);
        } else {
            emit_return(s, FALSE);
        }
        if (js_parse_expect_semi(s))
            goto fail;
        break;
    case TOK_THROW:
        if (next_token(s))
            goto fail;
        if (s->got_lf) {
            js_parse_error(s, "line terminator not allowed after throw");
            goto fail;
        }
        if (js_parse_expr(s))
            goto fail;
        emit_op(s, OP_throw);
        if (js_parse_expect_semi(s))
            goto fail;
        break;
    case TOK_LET:
    case TOK_CONST:
    haslet:
        if (!(decl_mask & DECL_MASK_OTHER)) {
            js_parse_error(s, "lexical declarations can't appear in single-statement context");
            goto fail;
        }
        /* fall thru */
    case TOK_VAR:
        if (next_token(s))
            goto fail;
        if (js_parse_var(s, TRUE, tok, FALSE))
            goto fail;
        if (js_parse_expect_semi(s))
            goto fail;
        break;
    case TOK_IF:
        {
            int label1, label2, mask;
            if (next_token(s))
                goto fail;
            /* create a new scope for `let f;if(1) function f(){}` */
            push_scope(s);
            set_eval_ret_undefined(s);
            if (js_parse_expr_paren(s))
                goto fail;
            label1 = emit_goto(s, OP_if_false, -1);
            if (s->cur_func->js_mode & JS_MODE_STRICT)
                mask = 0;
            else
                mask = DECL_MASK_FUNC; /* Annex B.3.4 */
            if (js_parse_statement_or_decl(s, mask))
                goto fail;
            if (s->token.val == TOK_ELSE) {
                label2 = emit_goto(s, OP_goto, -1);
                if (next_token(s))
                    goto fail;
                emit_label(s, label1);
                if (js_parse_statement_or_decl(s, mask))
                    goto fail;
                label1 = label2;
            }
            emit_label(s, label1);
            pop_scope(s);
        }
        break;
    case TOK_WHILE:
        {
            int label_cont, label_break;
            BlockEnv break_entry;
            label_cont = new_label(s);
            label_break = new_label(s);
            push_break_entry(s->cur_func, &break_entry,
                             label_name, label_break, label_cont, 0);
            if (next_token(s))
                goto fail;
            set_eval_ret_undefined(s);
            emit_label(s, label_cont);
            if (js_parse_expr_paren(s))
                goto fail;
            emit_goto(s, OP_if_false, label_break);
            if (js_parse_statement(s))
                goto fail;
            emit_goto(s, OP_goto, label_cont);
            emit_label(s, label_break);
            pop_break_entry(s->cur_func);
        }
        break;
    case TOK_DO:
        {
            int label_cont, label_break, label1;
            BlockEnv break_entry;
            label_cont = new_label(s);
            label_break = new_label(s);
            label1 = new_label(s);
            push_break_entry(s->cur_func, &break_entry,
                             label_name, label_break, label_cont, 0);
            if (next_token(s))
                goto fail;
            emit_label(s, label1);
            set_eval_ret_undefined(s);
            if (js_parse_statement(s))
                goto fail;
            emit_label(s, label_cont);
            if (js_parse_expect(s, TOK_WHILE))
                goto fail;
            if (js_parse_expr_paren(s))
                goto fail;
            /* Insert semicolon if missing */
            if (s->token.val == ';') {
                if (next_token(s))
                    goto fail;
            }
            emit_goto(s, OP_if_true, label1);
            emit_label(s, label_break);
            pop_break_entry(s->cur_func);
        }
        break;
    case TOK_FOR:
        {
            int label_cont, label_break, label_body, label_test;
            int pos_cont, pos_body, block_scope_level;
            BlockEnv break_entry;
            int tok, bits;
            BOOL is_async;
            if (next_token(s))
                goto fail;
            set_eval_ret_undefined(s);
            bits = 0;
            is_async = FALSE;
            if (s->token.val == '(') {
                js_parse_skip_parens_token(s, &bits, FALSE);
            } else if (s->token.val == TOK_AWAIT) {
                if (!(s->cur_func->func_kind & JS_FUNC_ASYNC)) {
                    js_parse_error(s, "for await is only valid in asynchronous functions");
                    goto fail;
                }
                is_async = TRUE;
                if (next_token(s))
                    goto fail;
            }
            if (js_parse_expect(s, '('))
                goto fail;
            if (!(bits & SKIP_HAS_SEMI)) {
                /* parse for/in or for/of */
                if (js_parse_for_in_of(s, label_name, is_async))
                    goto fail;
                break;
            }
            block_scope_level = s->cur_func->scope_level;
            /* create scope for the lexical variables declared in the initial,
               test and increment expressions */
            push_scope(s);
            /* initial expression */
            tok = s->token.val;
            if (tok != ';') {
                switch (is_let(s, DECL_MASK_OTHER)) {
                case TRUE:
                    tok = TOK_LET;
                    break;
                case FALSE:
                    break;
                default:
                    goto fail;
                }
                if (tok == TOK_VAR || tok == TOK_LET || tok == TOK_CONST) {
                    if (next_token(s))
                        goto fail;
                    if (js_parse_var(s, FALSE, tok, FALSE))
                        goto fail;
                } else {
                    if (js_parse_expr2(s, FALSE))
                        goto fail;
                    emit_op(s, OP_drop);
                }
                /* close the closures before the first iteration */
                close_scopes(s, s->cur_func->scope_level, block_scope_level);
            }
            if (js_parse_expect(s, ';'))
                goto fail;
            label_test = new_label(s);
            label_cont = new_label(s);
            label_body = new_label(s);
            label_break = new_label(s);
            push_break_entry(s->cur_func, &break_entry,
                             label_name, label_break, label_cont, 0);
            /* test expression */
            if (s->token.val == ';') {
                /* no test expression */
                label_test = label_body;
            } else {
                emit_label(s, label_test);
                if (js_parse_expr(s))
                    goto fail;
                emit_goto(s, OP_if_false, label_break);
            }
            if (js_parse_expect(s, ';'))
                goto fail;
            if (s->token.val == ')') {
                /* no end expression */
                break_entry.label_cont = label_cont = label_test;
                pos_cont = 0; /* avoid warning */
            } else {
                /* skip the end expression */
                emit_goto(s, OP_goto, label_body);
                pos_cont = s->cur_func->byte_code.size;
                emit_label(s, label_cont);
                if (js_parse_expr(s))
                    goto fail;
                emit_op(s, OP_drop);
                if (label_test != label_body)
                    emit_goto(s, OP_goto, label_test);
            }
            if (js_parse_expect(s, ')'))
                goto fail;
            pos_body = s->cur_func->byte_code.size;
            emit_label(s, label_body);
            if (js_parse_statement(s))
                goto fail;
            /* close the closures before the next iteration */
            /* XXX: check continue case */
            close_scopes(s, s->cur_func->scope_level, block_scope_level);
            if (OPTIMIZE && label_test != label_body && label_cont != label_test) {
                /* move the increment code here */
                DynBuf *bc = &s->cur_func->byte_code;
                int chunk_size = pos_body - pos_cont;
                int offset = bc->size - pos_cont;
                int i;
                dbuf_realloc(bc, bc->size + chunk_size);
                dbuf_put(bc, bc->buf + pos_cont, chunk_size);
                memset(bc->buf + pos_cont, OP_nop, chunk_size);
                /* increment part ends with a goto */
                s->cur_func->last_opcode_pos = bc->size - 5;
                /* relocate labels */
                for (i = label_cont; i < s->cur_func->label_count; i++) {
                    LabelSlot *ls = &s->cur_func->label_slots[i];
                    if (ls->pos >= pos_cont && ls->pos < pos_body)
                        ls->pos += offset;
                }
            } else {
                emit_goto(s, OP_goto, label_cont);
            }
            emit_label(s, label_break);
            pop_break_entry(s->cur_func);
            pop_scope(s);
        }
        break;
    case TOK_BREAK:
    case TOK_CONTINUE:
        {
            int is_cont = s->token.val - TOK_BREAK;
            int label;
            if (next_token(s))
                goto fail;
            if (!s->got_lf && s->token.val == TOK_IDENT && !s->token.u.ident.is_reserved)
                label = s->token.u.ident.atom;
            else
                label = JS_ATOM_NULL;
            if (emit_break(s, label, is_cont))
                goto fail;
            if (label != JS_ATOM_NULL) {
                if (next_token(s))
                    goto fail;
            }
            if (js_parse_expect_semi(s))
                goto fail;
        }
        break;
    case TOK_SWITCH:
        {
            int label_case, label_break, label1;
            int default_label_pos;
            BlockEnv break_entry;
            if (next_token(s))
                goto fail;
            set_eval_ret_undefined(s);
            if (js_parse_expr_paren(s))
                goto fail;
            push_scope(s);
            label_break = new_label(s);
            push_break_entry(s->cur_func, &break_entry,
                             label_name, label_break, -1, 1);
            if (js_parse_expect(s, '{'))
                goto fail;
            default_label_pos = -1;
            label_case = -1;
            while (s->token.val != '}') {
                if (s->token.val == TOK_CASE) {
                    label1 = -1;
                    if (label_case >= 0) {
                        /* skip the case if needed */
                        label1 = emit_goto(s, OP_goto, -1);
                    }
                    emit_label(s, label_case);
                    label_case = -1;
                    for (;;) {
                        /* parse a sequence of case clauses */
                        if (next_token(s))
                            goto fail;
                        emit_op(s, OP_dup);
                        if (js_parse_expr(s))
                            goto fail;
                        if (js_parse_expect(s, ':'))
                            goto fail;
                        emit_op(s, OP_strict_eq);
                        if (s->token.val == TOK_CASE) {
                            label1 = emit_goto(s, OP_if_true, label1);
                        } else {
                            label_case = emit_goto(s, OP_if_false, -1);
                            emit_label(s, label1);
                            break;
                        }
                    }
                } else if (s->token.val == TOK_DEFAULT) {
                    if (next_token(s))
                        goto fail;
                    if (js_parse_expect(s, ':'))
                        goto fail;
                    if (default_label_pos >= 0) {
                        js_parse_error(s, "duplicate default");
                        goto fail;
                    }
                    if (label_case < 0) {
                        /* falling thru direct from switch expression */
                        label_case = emit_goto(s, OP_goto, -1);
                    }
                    /* Emit a dummy label opcode. Label will be patched after
                       the end of the switch body. Do not use emit_label(s, 0)
                       because it would clobber label 0 address, preventing
                       proper optimizer operation.
                     */
                    emit_op(s, OP_label);
                    emit_u32(s, 0);
                    default_label_pos = s->cur_func->byte_code.size - 4;
                } else {
                    if (label_case < 0) {
                        /* falling thru direct from switch expression */
                        js_parse_error(s, "invalid switch statement");
                        goto fail;
                    }
                    if (js_parse_statement_or_decl(s, DECL_MASK_ALL))
                        goto fail;
                }
            }
            if (js_parse_expect(s, '}'))
                goto fail;
            if (default_label_pos >= 0) {
                /* Ugly patch for the the `default` label, shameful and risky */
                put_u32(s->cur_func->byte_code.buf + default_label_pos,
                        label_case);
                s->cur_func->label_slots[label_case].pos = default_label_pos + 4;
            } else {
                emit_label(s, label_case);
            }
            emit_label(s, label_break);
            emit_op(s, OP_drop); /* drop the switch expression */
            pop_break_entry(s->cur_func);
            pop_scope(s);
        }
        break;
    case TOK_TRY:
        {
            int label_catch, label_catch2, label_finally, label_end;
            JSAtom name;
            BlockEnv block_env;
            set_eval_ret_undefined(s);
            if (next_token(s))
                goto fail;
            label_catch = new_label(s);
            label_catch2 = new_label(s);
            label_finally = new_label(s);
            label_end = new_label(s);
            emit_goto(s, OP_catch, label_catch);
            push_break_entry(s->cur_func, &block_env,
                             JS_ATOM_NULL, -1, -1, 1);
            block_env.label_finally = label_finally;
            if (js_parse_block(s))
                goto fail;
            pop_break_entry(s->cur_func);
            if (js_is_live_code(s)) {
                /* drop the catch offset */
                emit_op(s, OP_drop);
                /* must push dummy value to keep same stack size */
                emit_op(s, OP_undefined);
                emit_goto(s, OP_gosub, label_finally);
                emit_op(s, OP_drop);
                emit_goto(s, OP_goto, label_end);
            }
            if (s->token.val == TOK_CATCH) {
                if (next_token(s))
                    goto fail;
                push_scope(s);  /* catch variable */
                emit_label(s, label_catch);
                if (s->token.val == '{') {
                    /* support optional-catch-binding feature */
                    emit_op(s, OP_drop);    /* pop the exception object */
                } else {
                    if (js_parse_expect(s, '('))
                        goto fail;
                    if (!(s->token.val == TOK_IDENT && !s->token.u.ident.is_reserved)) {
                        if (s->token.val == '[' || s->token.val == '{') {
                            /* XXX: TOK_LET is not completely correct */
                            if (js_parse_destructuring_element(s, TOK_LET, 0, TRUE, -1, TRUE) < 0)
                                goto fail;
                        } else {
                            js_parse_error(s, "identifier expected");
                            goto fail;
                        }
                    } else {
                        name = JS_DupAtom(ctx, s->token.u.ident.atom);
                        if (next_token(s)
                        ||  js_define_var(s, name, TOK_CATCH) < 0) {
                            JS_FreeAtom(ctx, name);
                            goto fail;
                        }
                        /* store the exception value in the catch variable */
                        emit_op(s, OP_scope_put_var);
                        emit_u32(s, name);
                        emit_u16(s, s->cur_func->scope_level);
                    }
                    if (js_parse_expect(s, ')'))
                        goto fail;
                }
                /* XXX: should keep the address to nop it out if there is no finally block */
                emit_goto(s, OP_catch, label_catch2);
                push_scope(s);  /* catch block */
                push_break_entry(s->cur_func, &block_env, JS_ATOM_NULL,
                                 -1, -1, 1);
                block_env.label_finally = label_finally;
                if (js_parse_block(s))
                    goto fail;
                pop_break_entry(s->cur_func);
                pop_scope(s);  /* catch block */
                pop_scope(s);  /* catch variable */
                if (js_is_live_code(s)) {
                    /* drop the catch2 offset */
                    emit_op(s, OP_drop);
                    /* XXX: should keep the address to nop it out if there is no finally block */
                    /* must push dummy value to keep same stack size */
                    emit_op(s, OP_undefined);
                    emit_goto(s, OP_gosub, label_finally);
                    emit_op(s, OP_drop);
                    emit_goto(s, OP_goto, label_end);
                }
                /* catch exceptions thrown in the catch block to execute the
                 * finally clause and rethrow the exception */
                emit_label(s, label_catch2);
                /* catch value is at TOS, no need to push undefined */
                emit_goto(s, OP_gosub, label_finally);
                emit_op(s, OP_throw);
            } else if (s->token.val == TOK_FINALLY) {
                /* finally without catch : execute the finally clause
                 * and rethrow the exception */
                emit_label(s, label_catch);
                /* catch value is at TOS, no need to push undefined */
                emit_goto(s, OP_gosub, label_finally);
                emit_op(s, OP_throw);
            } else {
                js_parse_error(s, "expecting catch or finally");
                goto fail;
            }
            emit_label(s, label_finally);
            if (s->token.val == TOK_FINALLY) {
                int saved_eval_ret_idx = 0; /* avoid warning */
                if (next_token(s))
                    goto fail;
                /* on the stack: ret_value gosub_ret_value */
                push_break_entry(s->cur_func, &block_env, JS_ATOM_NULL,
                                 -1, -1, 2);
                if (s->cur_func->eval_ret_idx >= 0) {
                    /* 'finally' updates eval_ret only if not a normal
                       termination */
                    saved_eval_ret_idx =
                        add_var(s->ctx, s->cur_func, JS_ATOM__ret_);
                    if (saved_eval_ret_idx < 0)
                        goto fail;
                    emit_op(s, OP_get_loc);
                    emit_u16(s, s->cur_func->eval_ret_idx);
                    emit_op(s, OP_put_loc);
                    emit_u16(s, saved_eval_ret_idx);
                    set_eval_ret_undefined(s);
                }
                if (js_parse_block(s))
                    goto fail;
                if (s->cur_func->eval_ret_idx >= 0) {
                    emit_op(s, OP_get_loc);
                    emit_u16(s, saved_eval_ret_idx);
                    emit_op(s, OP_put_loc);
                    emit_u16(s, s->cur_func->eval_ret_idx);
                }
                pop_break_entry(s->cur_func);
            }
            emit_op(s, OP_ret);
            emit_label(s, label_end);
        }
        break;
    case ';':
        /* empty statement */
        if (next_token(s))
            goto fail;
        break;
    case TOK_WITH:
        if (s->cur_func->js_mode & JS_MODE_STRICT) {
            js_parse_error(s, "invalid keyword: with");
            goto fail;
        } else {
            int with_idx;
            if (next_token(s))
                goto fail;
            if (js_parse_expr_paren(s))
                goto fail;
            push_scope(s);
            with_idx = define_var(s, s->cur_func, JS_ATOM__with_,
                                  JS_VAR_DEF_WITH);
            if (with_idx < 0)
                goto fail;
            emit_op(s, OP_to_object);
            emit_op(s, OP_put_loc);
            emit_u16(s, with_idx);
            set_eval_ret_undefined(s);
            if (js_parse_statement(s))
                goto fail;
            /* Popping scope drops lexical context for the with object variable */
            pop_scope(s);
        }
        break;
    case TOK_FUNCTION:
        /* ES6 Annex B.3.2 and B.3.3 semantics */
        if (!(decl_mask & DECL_MASK_FUNC))
            goto func_decl_error;
        if (!(decl_mask & DECL_MASK_OTHER) && peek_token(s, FALSE) == '*')
            goto func_decl_error;
        goto parse_func_var;
    case TOK_IDENT:
        if (s->token.u.ident.is_reserved) {
            js_parse_error_reserved_identifier(s);
            goto fail;
        }
        /* Determine if `let` introduces a Declaration or an ExpressionStatement */
        switch (is_let(s, decl_mask)) {
        case TRUE:
            tok = TOK_LET;
            goto haslet;
        case FALSE:
            break;
        default:
            goto fail;
        }
        if (token_is_pseudo_keyword(s, JS_ATOM_async) &&
            peek_token(s, TRUE) == TOK_FUNCTION) {
            if (!(decl_mask & DECL_MASK_OTHER)) {
            func_decl_error:
                js_parse_error(s, "function declarations can't appear in single-statement context");
                goto fail;
            }
        parse_func_var:
            if (js_parse_function_decl(s, JS_PARSE_FUNC_VAR,
                                       JS_FUNC_NORMAL, JS_ATOM_NULL,
                                       s->token.ptr, s->token.line_num))
                goto fail;
            break;
        }
        goto hasexpr;
    case TOK_CLASS:
        if (!(decl_mask & DECL_MASK_OTHER)) {
            js_parse_error(s, "class declarations can't appear in single-statement context");
            goto fail;
        }
        if (js_parse_class(s, FALSE, JS_PARSE_EXPORT_NONE))
            return -1;
        break;
    case TOK_DEBUGGER:
        /* currently no debugger, so just skip the keyword */
        if (next_token(s))
            goto fail;
        if (js_parse_expect_semi(s))
            goto fail;
        break;
    case TOK_ENUM:
    case TOK_EXPORT:
    case TOK_EXTENDS:
        js_unsupported_keyword(s, s->token.u.ident.atom);
        goto fail;
    default:
    hasexpr:
        if (js_parse_expr(s))
            goto fail;
        if (s->cur_func->eval_ret_idx >= 0) {
            /* store the expression value so that it can be returned
               by eval() */
            emit_op(s, OP_put_loc);
            emit_u16(s, s->cur_func->eval_ret_idx);
        } else {
            emit_op(s, OP_drop); /* drop the result */
        }
        if (js_parse_expect_semi(s))
            goto fail;
        break;
    }
done:
    JS_FreeAtom(ctx, label_name);
    return 0;
fail:
    JS_FreeAtom(ctx, label_name);
    return -1;
}

static __exception int js_parse_delete(JSParseState *s)
{
    JSFunctionDef *fd = s->cur_func;
    JSAtom name;
    int opcode;
    if (next_token(s))
        return -1;
    if (js_parse_unary(s, PF_POW_FORBIDDEN))
        return -1;
    switch(opcode = get_prev_opcode(fd)) {
    case OP_get_field:
        {
            JSValue val;
            int ret;
            name = get_u32(fd->byte_code.buf + fd->last_opcode_pos + 1);
            fd->byte_code.size = fd->last_opcode_pos;
            fd->last_opcode_pos = -1;
            val = JS_AtomToValue(s->ctx, name);
            ret = emit_push_const(s, val, 1);
            JS_FreeValue(s->ctx, val);
            JS_FreeAtom(s->ctx, name);
            if (ret)
                return ret;
        }
        goto do_delete;
    case OP_get_array_el:
        fd->byte_code.size = fd->last_opcode_pos;
        fd->last_opcode_pos = -1;
    do_delete:
        emit_op(s, OP_delete);
        break;
    case OP_scope_get_var:
        /* 'delete this': this is not a reference */
        name = get_u32(fd->byte_code.buf + fd->last_opcode_pos + 1);
        if (name == JS_ATOM_this || name == JS_ATOM_new_target)
            goto ret_true;
        if (fd->js_mode & JS_MODE_STRICT) {
            return js_parse_error(s, "cannot delete a direct reference in strict mode");
        } else {
            fd->byte_code.buf[fd->last_opcode_pos] = OP_scope_delete_var;
        }
        break;
    case OP_scope_get_private_field:
        return js_parse_error(s, "cannot delete a private class field");
    case OP_get_super_value:
        emit_op(s, OP_throw_error);
        emit_atom(s, JS_ATOM_NULL);
        emit_u8(s, JS_THROW_ERROR_DELETE_SUPER);
        break;
    default:
    ret_true:
        emit_op(s, OP_drop);
        emit_op(s, OP_push_true);
        break;
    }
    return 0;
}

/* allowed parse_flags: PF_ARROW_FUNC, PF_POW_ALLOWED, PF_POW_FORBIDDEN */
static __exception int js_parse_unary(JSParseState *s, int parse_flags)
{
    int op;
    switch(s->token.val) {
    case '+':
    case '-':
    case '!':
    case '~':
    case TOK_VOID:
        op = s->token.val;
        if (next_token(s))
            return -1;
        if (js_parse_unary(s, PF_POW_FORBIDDEN))
            return -1;
        switch(op) {
        case '-':
            emit_op(s, OP_neg);
            break;
        case '+':
            emit_op(s, OP_plus);
            break;
        case '!':
            emit_op(s, OP_lnot);
            break;
        case '~':
            emit_op(s, OP_not);
            break;
        case TOK_VOID:
            emit_op(s, OP_drop);
            emit_op(s, OP_undefined);
            break;
        default:
            abort();
        }
        parse_flags = 0;
        break;
    case TOK_DEC:
    case TOK_INC:
        {
            int opcode, op, scope, label;
            JSAtom name;
            op = s->token.val;
            if (next_token(s))
                return -1;
            if (js_parse_unary(s, 0))
                return -1;
            if (get_lvalue(s, &opcode, &scope, &name, &label, NULL, TRUE, op))
                return -1;
            emit_op(s, OP_dec + op - TOK_DEC);
            put_lvalue(s, opcode, scope, name, label, PUT_LVALUE_KEEP_TOP,
                       FALSE);
        }
        break;
    case TOK_TYPEOF:
        {
            JSFunctionDef *fd;
            if (next_token(s))
                return -1;
            if (js_parse_unary(s, PF_POW_FORBIDDEN))
                return -1;
            /* reference access should not return an exception, so we
               patch the get_var */
            fd = s->cur_func;
            if (get_prev_opcode(fd) == OP_scope_get_var) {
                fd->byte_code.buf[fd->last_opcode_pos] = OP_scope_get_var_undef;
            }
            emit_op(s, OP_typeof);
            parse_flags = 0;
        }
        break;
    case TOK_DELETE:
        if (js_parse_delete(s))
            return -1;
        parse_flags = 0;
        break;
    case TOK_AWAIT:
        if (!(s->cur_func->func_kind & JS_FUNC_ASYNC))
            return js_parse_error(s, "unexpected 'await' keyword");
        if (!s->cur_func->in_function_body)
            return js_parse_error(s, "await in default expression");
        if (next_token(s))
            return -1;
        if (js_parse_unary(s, PF_POW_FORBIDDEN))
            return -1;
        emit_op(s, OP_await);
        parse_flags = 0;
        break;
    default:
        if (js_parse_postfix_expr(s, (parse_flags & PF_ARROW_FUNC) |
                                  PF_POSTFIX_CALL))
            return -1;
        if (!s->got_lf &&
            (s->token.val == TOK_DEC || s->token.val == TOK_INC)) {
            int opcode, op, scope, label;
            JSAtom name;
            op = s->token.val;
            if (get_lvalue(s, &opcode, &scope, &name, &label, NULL, TRUE, op))
                return -1;
            emit_op(s, OP_post_dec + op - TOK_DEC);
            put_lvalue(s, opcode, scope, name, label, PUT_LVALUE_KEEP_SECOND,
                       FALSE);
            if (next_token(s))
                return -1;
        }
        break;
    }
    if (parse_flags & (PF_POW_ALLOWED | PF_POW_FORBIDDEN)) {
#ifdef CONFIG_BIGNUM
        if (s->token.val == TOK_POW || s->token.val == TOK_MATH_POW) {
            /* Extended exponentiation syntax rules: we extend the ES7
               grammar in order to have more intuitive semantics:
               -2**2 evaluates to -4. */
            if (!(s->cur_func->js_mode & JS_MODE_MATH)) {
                if (parse_flags & PF_POW_FORBIDDEN) {
                    JS_ThrowSyntaxError(s->ctx, "unparenthesized unary expression can't appear on the left-hand side of '**'");
                    return -1;
                }
            }
            if (next_token(s))
                return -1;
            if (js_parse_unary(s, PF_POW_ALLOWED))
                return -1;
            emit_op(s, OP_pow);
        }
#else
        if (s->token.val == TOK_POW) {
            /* Strict ES7 exponentiation syntax rules: To solve
               conficting semantics between different implementations
               regarding the precedence of prefix operators and the
               postifx exponential, ES7 specifies that -2**2 is a
               syntax error. */
            if (parse_flags & PF_POW_FORBIDDEN) {
                JS_ThrowSyntaxError(s->ctx, "unparenthesized unary expression can't appear on the left-hand side of '**'");
                return -1;
            }
            if (next_token(s))
                return -1;
            if (js_parse_unary(s, PF_POW_ALLOWED))
                return -1;
            emit_op(s, OP_pow);
        }
#endif
    }
    return 0;
}

/* allowed parse_flags: PF_ARROW_FUNC, PF_IN_ACCEPTED */
static __exception int js_parse_expr_binary(JSParseState *s, int level,
                                            int parse_flags)
{
    int op, opcode;
    if (level == 0) {
        return js_parse_unary(s, (parse_flags & PF_ARROW_FUNC) |
                              PF_POW_ALLOWED);
    }
    if (js_parse_expr_binary(s, level - 1, parse_flags))
        return -1;
    for(;;) {
        op = s->token.val;
        switch(level) {
        case 1:
            switch(op) {
            case '*':
                opcode = OP_mul;
                break;
            case '/':
                opcode = OP_div;
                break;
            case '%':
#ifdef CONFIG_BIGNUM
                if (s->cur_func->js_mode & JS_MODE_MATH)
                    opcode = OP_math_mod;
                else
#endif
                    opcode = OP_mod;
                break;
            default:
                return 0;
            }
            break;
        case 2:
            switch(op) {
            case '+':
                opcode = OP_add;
                break;
            case '-':
                opcode = OP_sub;
                break;
            default:
                return 0;
            }
            break;
        case 3:
            switch(op) {
            case TOK_SHL:
                opcode = OP_shl;
                break;
            case TOK_SAR:
                opcode = OP_sar;
                break;
            case TOK_SHR:
                opcode = OP_shr;
                break;
            default:
                return 0;
            }
            break;
        case 4:
            switch(op) {
            case '<':
                opcode = OP_lt;
                break;
            case '>':
                opcode = OP_gt;
                break;
            case TOK_LTE:
                opcode = OP_lte;
                break;
            case TOK_GTE:
                opcode = OP_gte;
                break;
            case TOK_INSTANCEOF:
                opcode = OP_instanceof;
                break;
            case TOK_IN:
                if (parse_flags & PF_IN_ACCEPTED) {
                    opcode = OP_in;
                } else {
                    return 0;
                }
                break;
            default:
                return 0;
            }
            break;
        case 5:
            switch(op) {
            case TOK_EQ:
                opcode = OP_eq;
                break;
            case TOK_NEQ:
                opcode = OP_neq;
                break;
            case TOK_STRICT_EQ:
                opcode = OP_strict_eq;
                break;
            case TOK_STRICT_NEQ:
                opcode = OP_strict_neq;
                break;
            default:
                return 0;
            }
            break;
        case 6:
            switch(op) {
            case '&':
                opcode = OP_and;
                break;
            default:
                return 0;
            }
            break;
        case 7:
            switch(op) {
            case '^':
                opcode = OP_xor;
                break;
            default:
                return 0;
            }
            break;
        case 8:
            switch(op) {
            case '|':
                opcode = OP_or;
                break;
            default:
                return 0;
            }
            break;
        default:
            abort();
        }
        if (next_token(s))
            return -1;
        if (js_parse_expr_binary(s, level - 1, parse_flags & ~PF_ARROW_FUNC))
            return -1;
        emit_op(s, opcode);
    }
    return 0;
}

/* allowed parse_flags: PF_ARROW_FUNC, PF_IN_ACCEPTED */
static __exception int js_parse_logical_and_or(JSParseState *s, int op,
                                               int parse_flags)
{
    int label1;
    if (op == TOK_LAND) {
        if (js_parse_expr_binary(s, 8, parse_flags))
            return -1;
    } else {
        if (js_parse_logical_and_or(s, TOK_LAND, parse_flags))
            return -1;
    }
    if (s->token.val == op) {
        label1 = new_label(s);
        for(;;) {
            if (next_token(s))
                return -1;
            emit_op(s, OP_dup);
            emit_goto(s, op == TOK_LAND ? OP_if_false : OP_if_true, label1);
            emit_op(s, OP_drop);
            if (op == TOK_LAND) {
                if (js_parse_expr_binary(s, 8, parse_flags & ~PF_ARROW_FUNC))
                    return -1;
            } else {
                if (js_parse_logical_and_or(s, TOK_LAND,
                                            parse_flags & ~PF_ARROW_FUNC))
                    return -1;
            }
            if (s->token.val != op) {
                if (s->token.val == TOK_DOUBLE_QUESTION_MARK)
                    return js_parse_error(s, "cannot mix ?? with && or ||");
                break;
            }
        }
        emit_label(s, label1);
    }
    return 0;
}

static __exception int js_parse_coalesce_expr(JSParseState *s, int parse_flags)
{
    int label1;
    if (js_parse_logical_and_or(s, TOK_LOR, parse_flags))
        return -1;
    if (s->token.val == TOK_DOUBLE_QUESTION_MARK) {
        label1 = new_label(s);
        for(;;) {
            if (next_token(s))
                return -1;
            emit_op(s, OP_dup);
            emit_op(s, OP_is_undefined_or_null);
            emit_goto(s, OP_if_false, label1);
            emit_op(s, OP_drop);
            if (js_parse_expr_binary(s, 8, parse_flags & ~PF_ARROW_FUNC))
                return -1;
            if (s->token.val != TOK_DOUBLE_QUESTION_MARK)
                break;
        }
        emit_label(s, label1);
    }
    return 0;
}

/* allowed parse_flags: PF_ARROW_FUNC, PF_IN_ACCEPTED */
static __exception int js_parse_cond_expr(JSParseState *s, int parse_flags)
{
    int label1, label2;
    if (js_parse_coalesce_expr(s, parse_flags))
        return -1;
    if (s->token.val == '?') {
        if (next_token(s))
            return -1;
        label1 = emit_goto(s, OP_if_false, -1);
        if (js_parse_assign_expr(s))
            return -1;
        if (js_parse_expect(s, ':'))
            return -1;
        label2 = emit_goto(s, OP_goto, -1);
        emit_label(s, label1);
        if (js_parse_assign_expr2(s, parse_flags & PF_IN_ACCEPTED))
            return -1;
        emit_label(s, label2);
    }
    return 0;
}

/* allowed parse_flags: PF_IN_ACCEPTED */
static __exception int js_parse_assign_expr2(JSParseState *s, int parse_flags)
{
    int opcode, op, scope;
    JSAtom name0 = JS_ATOM_NULL;
    JSAtom name;
    if (s->token.val == TOK_YIELD) {
        BOOL is_star = FALSE, is_async;
        if (!(s->cur_func->func_kind & JS_FUNC_GENERATOR))
            return js_parse_error(s, "unexpected 'yield' keyword");
        if (!s->cur_func->in_function_body)
            return js_parse_error(s, "yield in default expression");
        if (next_token(s))
            return -1;
        /* XXX: is there a better method to detect 'yield' without
           parameters ? */
        if (s->token.val != ';' && s->token.val != ')' &&
            s->token.val != ']' && s->token.val != '}' &&
            s->token.val != ',' && s->token.val != ':' && !s->got_lf) {
            if (s->token.val == '*') {
                is_star = TRUE;
                if (next_token(s))
                    return -1;
            }
            if (js_parse_assign_expr2(s, parse_flags))
                return -1;
        } else {
            emit_op(s, OP_undefined);
        }
        is_async = (s->cur_func->func_kind == JS_FUNC_ASYNC_GENERATOR);
        if (is_star) {
            int label_loop, label_return, label_next;
            int label_return1, label_yield, label_throw, label_throw1;
            int label_throw2;
            label_loop = new_label(s);
            label_yield = new_label(s);
            emit_op(s, is_async ? OP_for_await_of_start : OP_for_of_start);
            /* remove the catch offset (XXX: could avoid pushing back
               undefined) */
            emit_op(s, OP_drop);
            emit_op(s, OP_undefined);
            emit_op(s, OP_undefined); /* initial value */
            emit_label(s, label_loop);
            emit_op(s, OP_iterator_next);
            if (is_async)
                emit_op(s, OP_await);
            emit_op(s, OP_iterator_check_object);
            emit_op(s, OP_get_field2);
            emit_atom(s, JS_ATOM_done);
            label_next = emit_goto(s, OP_if_true, -1); /* end of loop */
            emit_label(s, label_yield);
            if (is_async) {
                /* OP_async_yield_star takes the value as parameter */
                emit_op(s, OP_get_field);
                emit_atom(s, JS_ATOM_value);
                emit_op(s, OP_await);
                emit_op(s, OP_async_yield_star);
            } else {
                /* OP_yield_star takes (value, done) as parameter */
                emit_op(s, OP_yield_star);
            }
            emit_op(s, OP_dup);
            label_return = emit_goto(s, OP_if_true, -1);
            emit_op(s, OP_drop);
            emit_goto(s, OP_goto, label_loop);
            emit_label(s, label_return);
            emit_op(s, OP_push_i32);
            emit_u32(s, 2);
            emit_op(s, OP_strict_eq);
            label_throw = emit_goto(s, OP_if_true, -1);
            /* return handling */
            if (is_async)
                emit_op(s, OP_await);
            emit_op(s, OP_iterator_call);
            emit_u8(s, 0);
            label_return1 = emit_goto(s, OP_if_true, -1);
            if (is_async)
                emit_op(s, OP_await);
            emit_op(s, OP_iterator_check_object);
            emit_op(s, OP_get_field2);
            emit_atom(s, JS_ATOM_done);
            emit_goto(s, OP_if_false, label_yield);
            emit_op(s, OP_get_field);
            emit_atom(s, JS_ATOM_value);
            emit_label(s, label_return1);
            emit_op(s, OP_nip);
            emit_op(s, OP_nip);
            emit_op(s, OP_nip);
            emit_return(s, TRUE);
            /* throw handling */
            emit_label(s, label_throw);
            emit_op(s, OP_iterator_call);
            emit_u8(s, 1);
            label_throw1 = emit_goto(s, OP_if_true, -1);
            if (is_async)
                emit_op(s, OP_await);
            emit_op(s, OP_iterator_check_object);
            emit_op(s, OP_get_field2);
            emit_atom(s, JS_ATOM_done);
            emit_goto(s, OP_if_false, label_yield);
            emit_goto(s, OP_goto, label_next);
            /* close the iterator and throw a type error exception */
            emit_label(s, label_throw1);
            emit_op(s, OP_iterator_call);
            emit_u8(s, 2);
            label_throw2 = emit_goto(s, OP_if_true, -1);
            if (is_async)
                emit_op(s, OP_await);
            emit_label(s, label_throw2);
            emit_op(s, OP_throw_error);
            emit_atom(s, JS_ATOM_NULL);
            emit_u8(s, JS_THROW_ERROR_ITERATOR_THROW);
            emit_label(s, label_next);
            emit_op(s, OP_get_field);
            emit_atom(s, JS_ATOM_value);
            emit_op(s, OP_nip); /* keep the value associated with
                                   done = true */
            emit_op(s, OP_nip);
            emit_op(s, OP_nip);
        } else {
            int label_next;
            if (is_async)
                emit_op(s, OP_await);
            emit_op(s, OP_yield);
            label_next = emit_goto(s, OP_if_false, -1);
            emit_return(s, TRUE);
            emit_label(s, label_next);
        }
        return 0;
    }
    if (s->token.val == TOK_IDENT) {
        /* name0 is used to check for OP_set_name pattern, not duplicated */
        name0 = s->token.u.ident.atom;
    }
    if (js_parse_cond_expr(s, parse_flags | PF_ARROW_FUNC))
        return -1;
    op = s->token.val;
    if (op == '=' || (op >= TOK_MUL_ASSIGN && op <= TOK_POW_ASSIGN)) {
        int label;
        if (next_token(s))
            return -1;
        if (get_lvalue(s, &opcode, &scope, &name, &label, NULL, (op != '='), op) < 0)
            return -1;
        if (js_parse_assign_expr2(s, parse_flags)) {
            JS_FreeAtom(s->ctx, name);
            return -1;
        }
        if (op == '=') {
            if (opcode == OP_get_ref_value && name == name0) {
                set_object_name(s, name);
            }
        } else {
            static const uint8_t assign_opcodes[] = {
                OP_mul, OP_div, OP_mod, OP_add, OP_sub,
                OP_shl, OP_sar, OP_shr, OP_and, OP_xor, OP_or,
#ifdef CONFIG_BIGNUM
                OP_pow,
#endif
                OP_pow,
            };
            op = assign_opcodes[op - TOK_MUL_ASSIGN];
#ifdef CONFIG_BIGNUM
            if (s->cur_func->js_mode & JS_MODE_MATH) {
                if (op == OP_mod)
                    op = OP_math_mod;
            }
#endif
            emit_op(s, op);
        }
        put_lvalue(s, opcode, scope, name, label, PUT_LVALUE_KEEP_TOP, FALSE);
    } else if (op >= TOK_LAND_ASSIGN && op <= TOK_DOUBLE_QUESTION_MARK_ASSIGN) {
        int label, label1, depth_lvalue, label2;
        if (next_token(s))
            return -1;
        if (get_lvalue(s, &opcode, &scope, &name, &label,
                       &depth_lvalue, TRUE, op) < 0)
            return -1;
        emit_op(s, OP_dup);
        if (op == TOK_DOUBLE_QUESTION_MARK_ASSIGN)
            emit_op(s, OP_is_undefined_or_null);
        label1 = emit_goto(s, op == TOK_LOR_ASSIGN ? OP_if_true : OP_if_false,
                           -1);
        emit_op(s, OP_drop);
        if (js_parse_assign_expr2(s, parse_flags)) {
            JS_FreeAtom(s->ctx, name);
            return -1;
        }
        if (opcode == OP_get_ref_value && name == name0) {
            set_object_name(s, name);
        }
        switch(depth_lvalue) {
        case 1:
            emit_op(s, OP_insert2);
            break;
        case 2:
            emit_op(s, OP_insert3);
            break;
        case 3:
            emit_op(s, OP_insert4);
            break;
        default:
            abort();
        }
        /* XXX: we disable the OP_put_ref_value optimization by not
           using put_lvalue() otherwise depth_lvalue is not correct */
        put_lvalue(s, opcode, scope, name, label, PUT_LVALUE_NOKEEP_DEPTH,
                   FALSE);
        label2 = emit_goto(s, OP_goto, -1);
        emit_label(s, label1);
        /* remove the lvalue stack entries */
        while (depth_lvalue != 0) {
            emit_op(s, OP_nip);
            depth_lvalue--;
        }
        emit_label(s, label2);
    }
    return 0;
}

static __exception int js_parse_assign_expr(JSParseState *s)
{
    return js_parse_assign_expr2(s, PF_IN_ACCEPTED);
}

static __exception int js_parse_expr(JSParseState *s)
{
    return js_parse_expr2(s, PF_IN_ACCEPTED);
}

static __exception JSAtom js_parse_from_clause(JSParseState *s)
{
    JSAtom module_name;
    if (!token_is_pseudo_keyword(s, JS_ATOM_from)) {
        js_parse_error(s, "from clause expected");
        return JS_ATOM_NULL;
    }
    if (next_token(s))
        return JS_ATOM_NULL;
    if (s->token.val != TOK_STRING) {
        js_parse_error(s, "string expected");
        return JS_ATOM_NULL;
    }
    module_name = JS_ValueToAtom(s->ctx, s->token.u.str.str);
    if (module_name == JS_ATOM_NULL)
        return JS_ATOM_NULL;
    if (next_token(s)) {
        JS_FreeAtom(s->ctx, module_name);
        return JS_ATOM_NULL;
    }
    return module_name;
}

static int add_import(JSParseState *s, JSModuleDef *m,
                      JSAtom local_name, JSAtom import_name)
{
    JSContext *ctx = s->ctx;
    int i, var_idx;
    JSImportEntry *mi;
    BOOL is_local;
    if (local_name == JS_ATOM_arguments || local_name == JS_ATOM_eval)
        return js_parse_error(s, "invalid import binding");
    if (local_name != JS_ATOM_default) {
        for (i = 0; i < s->cur_func->closure_var_count; i++) {
            if (s->cur_func->closure_var[i].var_name == local_name)
                return js_parse_error(s, "duplicate import binding");
        }
    }
    is_local = (import_name == JS_ATOM__star_);
    var_idx = add_closure_var(ctx, s->cur_func, is_local, FALSE,
                              m->import_entries_count,
                              local_name, TRUE, TRUE, FALSE);
    if (var_idx < 0)
        return -1;
    if (js_resize_array(ctx, (void **)&m->import_entries,
                        sizeof(JSImportEntry),
                        &m->import_entries_size,
                        m->import_entries_count + 1))
        return -1;
    mi = &m->import_entries[m->import_entries_count++];
    mi->import_name = JS_DupAtom(ctx, import_name);
    mi->var_idx = var_idx;
    return 0;
}

static int add_req_module_entry(JSContext *ctx, JSModuleDef *m,
                                JSAtom module_name)
{
    JSReqModuleEntry *rme;
    int i;
    /* no need to add the module request if it is already present */
    for(i = 0; i < m->req_module_entries_count; i++) {
        rme = &m->req_module_entries[i];
        if (rme->module_name == module_name)
            return i;
    }
    if (js_resize_array(ctx, (void **)&m->req_module_entries,
                        sizeof(JSReqModuleEntry),
                        &m->req_module_entries_size,
                        m->req_module_entries_count + 1))
        return -1;
    rme = &m->req_module_entries[m->req_module_entries_count++];
    rme->module_name = JS_DupAtom(ctx, module_name);
    rme->module = NULL;
    return i;
}

static __exception int js_parse_import(JSParseState *s)
{
    JSContext *ctx = s->ctx;
    JSModuleDef *m = s->cur_func->module;
    JSAtom local_name, import_name, module_name;
    int first_import, i, idx;
    if (next_token(s))
        return -1;
    first_import = m->import_entries_count;
    if (s->token.val == TOK_STRING) {
        module_name = JS_ValueToAtom(ctx, s->token.u.str.str);
        if (module_name == JS_ATOM_NULL)
            return -1;
        if (next_token(s)) {
            JS_FreeAtom(ctx, module_name);
            return -1;
        }
    } else {
        if (s->token.val == TOK_IDENT) {
            if (s->token.u.ident.is_reserved) {
                return js_parse_error_reserved_identifier(s);
            }
            /* "default" import */
            local_name = JS_DupAtom(ctx, s->token.u.ident.atom);
            import_name = JS_ATOM_default;
            if (next_token(s))
                goto fail;
            if (add_import(s, m, local_name, import_name))
                goto fail;
            JS_FreeAtom(ctx, local_name);
            if (s->token.val != ',')
                goto end_import_clause;
            if (next_token(s))
                return -1;
        }
        if (s->token.val == '*') {
            /* name space import */
            if (next_token(s))
                return -1;
            if (!token_is_pseudo_keyword(s, JS_ATOM_as))
                return js_parse_error(s, "expecting 'as'");
            if (next_token(s))
                return -1;
            if (!token_is_ident(s->token.val)) {
                js_parse_error(s, "identifier expected");
                return -1;
            }
            local_name = JS_DupAtom(ctx, s->token.u.ident.atom);
            import_name = JS_ATOM__star_;
            if (next_token(s))
                goto fail;
            if (add_import(s, m, local_name, import_name))
                goto fail;
            JS_FreeAtom(ctx, local_name);
        } else if (s->token.val == '{') {
            if (next_token(s))
                return -1;
            while (s->token.val != '}') {
                if (!token_is_ident(s->token.val)) {
                    js_parse_error(s, "identifier expected");
                    return -1;
                }
                import_name = JS_DupAtom(ctx, s->token.u.ident.atom);
                local_name = JS_ATOM_NULL;
                if (next_token(s))
                    goto fail;
                if (token_is_pseudo_keyword(s, JS_ATOM_as)) {
                    if (next_token(s))
                        goto fail;
                    if (!token_is_ident(s->token.val)) {
                        js_parse_error(s, "identifier expected");
                        goto fail;
                    }
                    local_name = JS_DupAtom(ctx, s->token.u.ident.atom);
                    if (next_token(s)) {
                    fail:
                        JS_FreeAtom(ctx, local_name);
                        JS_FreeAtom(ctx, import_name);
                        return -1;
                    }
                } else {
                    local_name = JS_DupAtom(ctx, import_name);
                }
                if (add_import(s, m, local_name, import_name))
                    goto fail;
                JS_FreeAtom(ctx, local_name);
                JS_FreeAtom(ctx, import_name);
                if (s->token.val != ',')
                    break;
                if (next_token(s))
                    return -1;
            }
            if (js_parse_expect(s, '}'))
                return -1;
        }
    end_import_clause:
        module_name = js_parse_from_clause(s);
        if (module_name == JS_ATOM_NULL)
            return -1;
    }
    idx = add_req_module_entry(ctx, m, module_name);
    JS_FreeAtom(ctx, module_name);
    if (idx < 0)
        return -1;
    for(i = first_import; i < m->import_entries_count; i++)
        m->import_entries[i].req_module_idx = idx;
    return js_parse_expect_semi(s);
}

static int add_star_export_entry(JSContext *ctx, JSModuleDef *m,
                                 int req_module_idx)
{
    JSStarExportEntry *se;
    if (js_resize_array(ctx, (void **)&m->star_export_entries,
                        sizeof(JSStarExportEntry),
                        &m->star_export_entries_size,
                        m->star_export_entries_count + 1))
        return -1;
    se = &m->star_export_entries[m->star_export_entries_count++];
    se->req_module_idx = req_module_idx;
    return 0;
}

int js_parse_export(JSParseState *s)
{
    JSContext *ctx = s->ctx;
    JSModuleDef *m = s->cur_func->module;
    JSAtom local_name, export_name;
    int first_export, idx, i, tok;
    JSAtom module_name;
    JSExportEntry *me;
    if (next_token(s))
        return -1;
    tok = s->token.val;
    if (tok == TOK_CLASS) {
        return js_parse_class(s, FALSE, JS_PARSE_EXPORT_NAMED);
    } else if (tok == TOK_FUNCTION ||
               (token_is_pseudo_keyword(s, JS_ATOM_async) &&
                peek_token(s, TRUE) == TOK_FUNCTION)) {
        return js_parse_function_decl2(s, JS_PARSE_FUNC_STATEMENT,
                                       JS_FUNC_NORMAL, JS_ATOM_NULL,
                                       s->token.ptr, s->token.line_num,
                                       JS_PARSE_EXPORT_NAMED, NULL);
    }
    if (next_token(s))
        return -1;
    switch(tok) {
    case '{':
        first_export = m->export_entries_count;
        while (s->token.val != '}') {
            if (!token_is_ident(s->token.val)) {
                js_parse_error(s, "identifier expected");
                return -1;
            }
            local_name = JS_DupAtom(ctx, s->token.u.ident.atom);
            export_name = JS_ATOM_NULL;
            if (next_token(s))
                goto fail;
            if (token_is_pseudo_keyword(s, JS_ATOM_as)) {
                if (next_token(s))
                    goto fail;
                if (!token_is_ident(s->token.val)) {
                    js_parse_error(s, "identifier expected");
                    goto fail;
                }
                export_name = JS_DupAtom(ctx, s->token.u.ident.atom);
                if (next_token(s)) {
                fail:
                    JS_FreeAtom(ctx, local_name);
                fail1:
                    JS_FreeAtom(ctx, export_name);
                    return -1;
                }
            } else {
                export_name = JS_DupAtom(ctx, local_name);
            }
            me = add_export_entry(s, m, local_name, export_name,
                                  JS_EXPORT_TYPE_LOCAL);
            JS_FreeAtom(ctx, local_name);
            JS_FreeAtom(ctx, export_name);
            if (!me)
                return -1;
            if (s->token.val != ',')
                break;
            if (next_token(s))
                return -1;
        }
        if (js_parse_expect(s, '}'))
            return -1;
        if (token_is_pseudo_keyword(s, JS_ATOM_from)) {
            module_name = js_parse_from_clause(s);
            if (module_name == JS_ATOM_NULL)
                return -1;
            idx = add_req_module_entry(ctx, m, module_name);
            JS_FreeAtom(ctx, module_name);
            if (idx < 0)
                return -1;
            for(i = first_export; i < m->export_entries_count; i++) {
                me = &m->export_entries[i];
                me->export_type = JS_EXPORT_TYPE_INDIRECT;
                me->u.req_module_idx = idx;
            }
        }
        break;
    case '*':
        if (token_is_pseudo_keyword(s, JS_ATOM_as)) {
            /* export ns from */
            if (next_token(s))
                return -1;
            if (!token_is_ident(s->token.val)) {
                js_parse_error(s, "identifier expected");
                return -1;
            }
            export_name = JS_DupAtom(ctx, s->token.u.ident.atom);
            if (next_token(s))
                goto fail1;
            module_name = js_parse_from_clause(s);
            if (module_name == JS_ATOM_NULL)
                goto fail1;
            idx = add_req_module_entry(ctx, m, module_name);
            JS_FreeAtom(ctx, module_name);
            if (idx < 0)
                goto fail1;
            me = add_export_entry(s, m, JS_ATOM__star_, export_name,
                                  JS_EXPORT_TYPE_INDIRECT);
            JS_FreeAtom(ctx, export_name);
            if (!me)
                return -1;
            me->u.req_module_idx = idx;
        } else {
            module_name = js_parse_from_clause(s);
            if (module_name == JS_ATOM_NULL)
                return -1;
            idx = add_req_module_entry(ctx, m, module_name);
            JS_FreeAtom(ctx, module_name);
            if (idx < 0)
                return -1;
            if (add_star_export_entry(ctx, m, idx) < 0)
                return -1;
        }
        break;
    case TOK_DEFAULT:
        if (s->token.val == TOK_CLASS) {
            return js_parse_class(s, FALSE, JS_PARSE_EXPORT_DEFAULT);
        } else if (s->token.val == TOK_FUNCTION ||
                   (token_is_pseudo_keyword(s, JS_ATOM_async) &&
                    peek_token(s, TRUE) == TOK_FUNCTION)) {
            return js_parse_function_decl2(s, JS_PARSE_FUNC_STATEMENT,
                                           JS_FUNC_NORMAL, JS_ATOM_NULL,
                                           s->token.ptr, s->token.line_num,
                                           JS_PARSE_EXPORT_DEFAULT, NULL);
        } else {
            if (js_parse_assign_expr(s))
                return -1;
        }
        /* set the name of anonymous functions */
        set_object_name(s, JS_ATOM_default);
        /* store the value in the _default_ global variable and export
           it */
        local_name = JS_ATOM__default_;
        if (define_var(s, s->cur_func, local_name, JS_VAR_DEF_LET) < 0)
            return -1;
        emit_op(s, OP_scope_put_var_init);
        emit_atom(s, local_name);
        emit_u16(s, 0);
        if (!add_export_entry(s, m, local_name, JS_ATOM_default,
                              JS_EXPORT_TYPE_LOCAL))
            return -1;
        break;
    case TOK_VAR:
    case TOK_LET:
    case TOK_CONST:
        return js_parse_var(s, TRUE, tok, TRUE);
    default:
        return js_parse_error(s, "invalid export syntax");
    }
    return js_parse_expect_semi(s);
}

static __exception int js_parse_source_element(JSParseState *s)
{
    JSFunctionDef *fd = s->cur_func;
    int tok;
    if (s->token.val == TOK_FUNCTION ||
        (token_is_pseudo_keyword(s, JS_ATOM_async) &&
         peek_token(s, TRUE) == TOK_FUNCTION)) {
        if (js_parse_function_decl(s, JS_PARSE_FUNC_STATEMENT,
                                   JS_FUNC_NORMAL, JS_ATOM_NULL,
                                   s->token.ptr, s->token.line_num))
            return -1;
    } else if (s->token.val == TOK_EXPORT && fd->module) {
        if (js_parse_export(s))
            return -1;
    } else if (s->token.val == TOK_IMPORT && fd->module &&
               ((tok = peek_token(s, FALSE)) != '(' && tok != '.'))  {
        /* the peek_token is needed to avoid confusion with ImportCall
           (dynamic import) or import.meta */
        if (js_parse_import(s))
            return -1;
    } else {
        if (js_parse_statement_or_decl(s, DECL_MASK_ALL))
            return -1;
    }
    return 0;
}

static __exception int js_parse_directives(JSParseState *s)
{
    char str[20];
    JSParsePos pos;
    BOOL has_semi;
    if (s->token.val != TOK_STRING)
        return 0;
    js_parse_get_pos(s, &pos);
    while(s->token.val == TOK_STRING) {
        /* Copy actual source string representation */
        snprintf(str, sizeof str, "%.*s",
                 (int)(s->buf_ptr - s->token.ptr - 2), s->token.ptr + 1);
        if (next_token(s))
            return -1;
        has_semi = FALSE;
        switch (s->token.val) {
        case ';':
            if (next_token(s))
                return -1;
            has_semi = TRUE;
            break;
        case '}':
        case TOK_EOF:
            has_semi = TRUE;
            break;
        case TOK_NUMBER:
        case TOK_STRING:
        case TOK_TEMPLATE:
        case TOK_IDENT:
        case TOK_REGEXP:
        case TOK_DEC:
        case TOK_INC:
        case TOK_NULL:
        case TOK_FALSE:
        case TOK_TRUE:
        case TOK_IF:
        case TOK_RETURN:
        case TOK_VAR:
        case TOK_THIS:
        case TOK_DELETE:
        case TOK_TYPEOF:
        case TOK_NEW:
        case TOK_DO:
        case TOK_WHILE:
        case TOK_FOR:
        case TOK_SWITCH:
        case TOK_THROW:
        case TOK_TRY:
        case TOK_FUNCTION:
        case TOK_DEBUGGER:
        case TOK_WITH:
        case TOK_CLASS:
        case TOK_CONST:
        case TOK_ENUM:
        case TOK_EXPORT:
        case TOK_IMPORT:
        case TOK_SUPER:
        case TOK_INTERFACE:
        case TOK_LET:
        case TOK_PACKAGE:
        case TOK_PRIVATE:
        case TOK_PROTECTED:
        case TOK_PUBLIC:
        case TOK_STATIC:
            /* automatic insertion of ';' */
            if (s->got_lf)
                has_semi = TRUE;
            break;
        default:
            break;
        }
        if (!has_semi)
            break;
        if (!strcmp(str, "use strict")) {
            s->cur_func->has_use_strict = TRUE;
            s->cur_func->js_mode |= JS_MODE_STRICT;
        }
#if !defined(DUMP_BYTECODE) || !(DUMP_BYTECODE & 8)
        else if (!strcmp(str, "use strip")) {
            s->cur_func->js_mode |= JS_MODE_STRIP;
        }
#endif
#ifdef CONFIG_BIGNUM
        else if (s->ctx->bignum_ext && !strcmp(str, "use math")) {
            s->cur_func->js_mode |= JS_MODE_MATH;
        }
#endif
    }
    return js_parse_seek_token(s, &pos);
}

static int js_parse_function_check_names(JSParseState *s, JSFunctionDef *fd,
                                         JSAtom func_name)
{
    JSAtom name;
    int i, idx;
    if (fd->js_mode & JS_MODE_STRICT) {
        if (!fd->has_simple_parameter_list && fd->has_use_strict) {
            return js_parse_error(s, "\"use strict\" not allowed in function with default or destructuring parameter");
        }
        if (func_name == JS_ATOM_eval || func_name == JS_ATOM_arguments) {
            return js_parse_error(s, "invalid function name in strict code");
        }
        for (idx = 0; idx < fd->arg_count; idx++) {
            name = fd->args[idx].var_name;
            if (name == JS_ATOM_eval || name == JS_ATOM_arguments) {
                return js_parse_error(s, "invalid argument name in strict code");
            }
        }
    }
    /* check async_generator case */
    if ((fd->js_mode & JS_MODE_STRICT)
    ||  !fd->has_simple_parameter_list
    ||  (fd->func_type == JS_PARSE_FUNC_METHOD && fd->func_kind == JS_FUNC_ASYNC)
    ||  fd->func_type == JS_PARSE_FUNC_ARROW
    ||  fd->func_type == JS_PARSE_FUNC_METHOD) {
        for (idx = 0; idx < fd->arg_count; idx++) {
            name = fd->args[idx].var_name;
            if (name != JS_ATOM_NULL) {
                for (i = 0; i < idx; i++) {
                    if (fd->args[i].var_name == name)
                        goto duplicate;
                }
                /* Check if argument name duplicates a destructuring parameter */
                /* XXX: should have a flag for such variables */
                for (i = 0; i < fd->var_count; i++) {
                    if (fd->vars[i].var_name == name &&
                        fd->vars[i].scope_level == 0)
                        goto duplicate;
                }
            }
        }
    }
    return 0;
duplicate:
    return js_parse_error(s, "duplicate argument names not allowed in this context");
}

static int add_arg(JSContext *ctx, JSFunctionDef *fd, JSAtom name)
{
    JSVarDef *vd;
    /* the local variable indexes are currently stored on 16 bits */
    if (fd->arg_count >= JS_MAX_LOCAL_VARS) {
        JS_ThrowInternalError(ctx, "too many arguments");
        return -1;
    }
    if (js_resize_array(ctx, (void **)&fd->args, sizeof(fd->args[0]),
                        &fd->arg_size, fd->arg_count + 1))
        return -1;
    vd = &fd->args[fd->arg_count++];
    bzero(vd, sizeof(*vd));
    vd->var_name = JS_DupAtom(ctx, name);
    vd->func_pool_idx = -1;
    return fd->arg_count - 1;
}

/* func_name must be JS_ATOM_NULL for JS_PARSE_FUNC_STATEMENT and
   JS_PARSE_FUNC_EXPR, JS_PARSE_FUNC_ARROW and JS_PARSE_FUNC_VAR */
static __exception int js_parse_function_decl2(JSParseState *s,
                                               JSParseFunctionEnum func_type,
                                               JSFunctionKindEnum func_kind,
                                               JSAtom func_name,
                                               const uint8_t *ptr,
                                               int function_line_num,
                                               JSParseExportEnum export_flag,
                                               JSFunctionDef **pfd)
{
    JSContext *ctx = s->ctx;
    JSFunctionDef *fd = s->cur_func;
    BOOL is_expr;
    int func_idx, lexical_func_idx = -1;
    BOOL has_opt_arg;
    BOOL create_func_var = FALSE;
    is_expr = (func_type != JS_PARSE_FUNC_STATEMENT &&
               func_type != JS_PARSE_FUNC_VAR);
    if (func_type == JS_PARSE_FUNC_STATEMENT ||
        func_type == JS_PARSE_FUNC_VAR ||
        func_type == JS_PARSE_FUNC_EXPR) {
        if (func_kind == JS_FUNC_NORMAL &&
            token_is_pseudo_keyword(s, JS_ATOM_async) &&
            peek_token(s, TRUE) != '\n') {
            if (next_token(s))
                return -1;
            func_kind = JS_FUNC_ASYNC;
        }
        if (next_token(s))
            return -1;
        if (s->token.val == '*') {
            if (next_token(s))
                return -1;
            func_kind |= JS_FUNC_GENERATOR;
        }
        if (s->token.val == TOK_IDENT) {
            if (s->token.u.ident.is_reserved ||
                (s->token.u.ident.atom == JS_ATOM_yield &&
                 func_type == JS_PARSE_FUNC_EXPR &&
                 (func_kind & JS_FUNC_GENERATOR)) ||
                (s->token.u.ident.atom == JS_ATOM_await &&
                 func_type == JS_PARSE_FUNC_EXPR &&
                 (func_kind & JS_FUNC_ASYNC))) {
                return js_parse_error_reserved_identifier(s);
            }
        }
        if (s->token.val == TOK_IDENT ||
            (((s->token.val == TOK_YIELD && !(fd->js_mode & JS_MODE_STRICT)) ||
             (s->token.val == TOK_AWAIT && !s->is_module)) &&
             func_type == JS_PARSE_FUNC_EXPR)) {
            func_name = JS_DupAtom(ctx, s->token.u.ident.atom);
            if (next_token(s)) {
                JS_FreeAtom(ctx, func_name);
                return -1;
            }
        } else {
            if (func_type != JS_PARSE_FUNC_EXPR &&
                export_flag != JS_PARSE_EXPORT_DEFAULT) {
                return js_parse_error(s, "function name expected");
            }
        }
    } else if (func_type != JS_PARSE_FUNC_ARROW) {
        func_name = JS_DupAtom(ctx, func_name);
    }
    if (fd->is_eval && fd->eval_type == JS_EVAL_TYPE_MODULE &&
        (func_type == JS_PARSE_FUNC_STATEMENT || func_type == JS_PARSE_FUNC_VAR)) {
        JSGlobalVar *hf;
        hf = find_global_var(fd, func_name);
        /* XXX: should check scope chain */
        if (hf && hf->scope_level == fd->scope_level) {
            js_parse_error(s, "invalid redefinition of global identifier in module code");
            JS_FreeAtom(ctx, func_name);
            return -1;
        }
    }
    if (func_type == JS_PARSE_FUNC_VAR) {
        if (!(fd->js_mode & JS_MODE_STRICT)
        && func_kind == JS_FUNC_NORMAL
        &&  find_lexical_decl(ctx, fd, func_name, fd->scope_first, FALSE) < 0
        &&  !((func_idx = find_var(ctx, fd, func_name)) >= 0 && (func_idx & ARGUMENT_VAR_OFFSET))
        &&  !(func_name == JS_ATOM_arguments && fd->has_arguments_binding)) {
            create_func_var = TRUE;
        }
        /* Create the lexical name here so that the function closure
           contains it */
        if (fd->is_eval &&
            (fd->eval_type == JS_EVAL_TYPE_GLOBAL ||
             fd->eval_type == JS_EVAL_TYPE_MODULE) &&
            fd->scope_level == fd->body_scope) {
            /* avoid creating a lexical variable in the global
               scope. XXX: check annex B */
            JSGlobalVar *hf;
            hf = find_global_var(fd, func_name);
            /* XXX: should check scope chain */
            if (hf && hf->scope_level == fd->scope_level) {
                js_parse_error(s, "invalid redefinition of global identifier");
                JS_FreeAtom(ctx, func_name);
                return -1;
            }
        } else {
            /* Always create a lexical name, fail if at the same scope as
               existing name */
            /* Lexical variable will be initialized upon entering scope */
            lexical_func_idx = define_var(s, fd, func_name,
                                          func_kind != JS_FUNC_NORMAL ?
                                          JS_VAR_DEF_NEW_FUNCTION_DECL :
                                          JS_VAR_DEF_FUNCTION_DECL);
            if (lexical_func_idx < 0) {
                JS_FreeAtom(ctx, func_name);
                return -1;
            }
        }
    }
    fd = js_new_function_def(ctx, fd, FALSE, is_expr,
                             s->filename, function_line_num);
    if (!fd) {
        JS_FreeAtom(ctx, func_name);
        return -1;
    }
    if (pfd)
        *pfd = fd;
    s->cur_func = fd;
    fd->func_name = func_name;
    /* XXX: test !fd->is_generator is always false */
    fd->has_prototype = (func_type == JS_PARSE_FUNC_STATEMENT ||
                         func_type == JS_PARSE_FUNC_VAR ||
                         func_type == JS_PARSE_FUNC_EXPR) &&
                        func_kind == JS_FUNC_NORMAL;
    fd->has_home_object = (func_type == JS_PARSE_FUNC_METHOD ||
                           func_type == JS_PARSE_FUNC_GETTER ||
                           func_type == JS_PARSE_FUNC_SETTER ||
                           func_type == JS_PARSE_FUNC_CLASS_CONSTRUCTOR ||
                           func_type == JS_PARSE_FUNC_DERIVED_CLASS_CONSTRUCTOR);
    fd->has_arguments_binding = (func_type != JS_PARSE_FUNC_ARROW);
    fd->has_this_binding = fd->has_arguments_binding;
    fd->is_derived_class_constructor = (func_type == JS_PARSE_FUNC_DERIVED_CLASS_CONSTRUCTOR);
    if (func_type == JS_PARSE_FUNC_ARROW) {
        fd->new_target_allowed = fd->parent->new_target_allowed;
        fd->super_call_allowed = fd->parent->super_call_allowed;
        fd->super_allowed = fd->parent->super_allowed;
        fd->arguments_allowed = fd->parent->arguments_allowed;
    } else {
        fd->new_target_allowed = TRUE;
        fd->super_call_allowed = fd->is_derived_class_constructor;
        fd->super_allowed = fd->has_home_object;
        fd->arguments_allowed = TRUE;
    }
    /* fd->in_function_body == FALSE prevents yield/await during the parsing
       of the arguments in generator/async functions. They are parsed as
       regular identifiers for other function kinds. */
    fd->func_kind = func_kind;
    fd->func_type = func_type;
    if (func_type == JS_PARSE_FUNC_CLASS_CONSTRUCTOR ||
        func_type == JS_PARSE_FUNC_DERIVED_CLASS_CONSTRUCTOR) {
        /* error if not invoked as a constructor */
        emit_op(s, OP_check_ctor);
    }
    if (func_type == JS_PARSE_FUNC_CLASS_CONSTRUCTOR) {
        emit_class_field_init(s);
    }
    /* parse arguments */
    fd->has_simple_parameter_list = TRUE;
    fd->has_parameter_expressions = FALSE;
    has_opt_arg = FALSE;
    if (func_type == JS_PARSE_FUNC_ARROW && s->token.val == TOK_IDENT) {
        JSAtom name;
        if (s->token.u.ident.is_reserved) {
            js_parse_error_reserved_identifier(s);
            goto fail;
        }
        name = s->token.u.ident.atom;
        if (add_arg(ctx, fd, name) < 0)
            goto fail;
        fd->defined_arg_count = 1;
    } else {
        if (s->token.val == '(') {
            int skip_bits;
            /* if there is an '=' inside the parameter list, we
               consider there is a parameter expression inside */
            js_parse_skip_parens_token(s, &skip_bits, FALSE);
            if (skip_bits & SKIP_HAS_ASSIGNMENT)
                fd->has_parameter_expressions = TRUE;
            if (next_token(s))
                goto fail;
        } else {
            if (js_parse_expect(s, '('))
                goto fail;
        }
        if (fd->has_parameter_expressions) {
            fd->scope_level = -1; /* force no parent scope */
            if (push_scope(s) < 0)
                return -1;
        }
        while (s->token.val != ')') {
            JSAtom name;
            BOOL rest = FALSE;
            int idx, has_initializer;
            if (s->token.val == TOK_ELLIPSIS) {
                fd->has_simple_parameter_list = FALSE;
                rest = TRUE;
                if (next_token(s))
                    goto fail;
            }
            if (s->token.val == '[' || s->token.val == '{') {
                fd->has_simple_parameter_list = FALSE;
                if (rest) {
                    emit_op(s, OP_rest);
                    emit_u16(s, fd->arg_count);
                } else {
                    /* unnamed arg for destructuring */
                    idx = add_arg(ctx, fd, JS_ATOM_NULL);
                    emit_op(s, OP_get_arg);
                    emit_u16(s, idx);
                }
                has_initializer = js_parse_destructuring_element(s, fd->has_parameter_expressions ? TOK_LET : TOK_VAR, 1, TRUE, -1, TRUE);
                if (has_initializer < 0)
                    goto fail;
                if (has_initializer)
                    has_opt_arg = TRUE;
                if (!has_opt_arg)
                    fd->defined_arg_count++;
            } else if (s->token.val == TOK_IDENT) {
                if (s->token.u.ident.is_reserved) {
                    js_parse_error_reserved_identifier(s);
                    goto fail;
                }
                name = s->token.u.ident.atom;
                if (name == JS_ATOM_yield && fd->func_kind == JS_FUNC_GENERATOR) {
                    js_parse_error_reserved_identifier(s);
                    goto fail;
                }
                if (fd->has_parameter_expressions) {
                    if (define_var(s, fd, name, JS_VAR_DEF_LET) < 0)
                        goto fail;
                }
                /* XXX: could avoid allocating an argument if rest is true */
                idx = add_arg(ctx, fd, name);
                if (idx < 0)
                    goto fail;
                if (next_token(s))
                    goto fail;
                if (rest) {
                    emit_op(s, OP_rest);
                    emit_u16(s, idx);
                    if (fd->has_parameter_expressions) {
                        emit_op(s, OP_dup);
                        emit_op(s, OP_scope_put_var_init);
                        emit_atom(s, name);
                        emit_u16(s, fd->scope_level);
                    }
                    emit_op(s, OP_put_arg);
                    emit_u16(s, idx);
                    fd->has_simple_parameter_list = FALSE;
                    has_opt_arg = TRUE;
                } else if (s->token.val == '=') {
                    int label;
                    fd->has_simple_parameter_list = FALSE;
                    has_opt_arg = TRUE;
                    if (next_token(s))
                        goto fail;
                    label = new_label(s);
                    emit_op(s, OP_get_arg);
                    emit_u16(s, idx);
                    emit_op(s, OP_dup);
                    emit_op(s, OP_undefined);
                    emit_op(s, OP_strict_eq);
                    emit_goto(s, OP_if_false, label);
                    emit_op(s, OP_drop);
                    if (js_parse_assign_expr(s))
                        goto fail;
                    set_object_name(s, name);
                    emit_op(s, OP_dup);
                    emit_op(s, OP_put_arg);
                    emit_u16(s, idx);
                    emit_label(s, label);
                    emit_op(s, OP_scope_put_var_init);
                    emit_atom(s, name);
                    emit_u16(s, fd->scope_level);
                } else {
                    if (!has_opt_arg) {
                        fd->defined_arg_count++;
                    }
                    if (fd->has_parameter_expressions) {
                        /* copy the argument to the argument scope */
                        emit_op(s, OP_get_arg);
                        emit_u16(s, idx);
                        emit_op(s, OP_scope_put_var_init);
                        emit_atom(s, name);
                        emit_u16(s, fd->scope_level);
                    }
                }
            } else {
                js_parse_error(s, "missing formal parameter");
                goto fail;
            }
            if (rest && s->token.val != ')') {
                js_parse_expect(s, ')');
                goto fail;
            }
            if (s->token.val == ')')
                break;
            if (js_parse_expect(s, ','))
                goto fail;
        }
        if ((func_type == JS_PARSE_FUNC_GETTER && fd->arg_count != 0) ||
            (func_type == JS_PARSE_FUNC_SETTER && fd->arg_count != 1)) {
            js_parse_error(s, "invalid number of arguments for getter or setter");
            goto fail;
        }
    }
    if (fd->has_parameter_expressions) {
        int idx;
        /* Copy the variables in the argument scope to the variable
           scope (see FunctionDeclarationInstantiation() in spec). The
           normal arguments are already present, so no need to copy
           them. */
        idx = fd->scopes[fd->scope_level].first;
        while (idx >= 0) {
            JSVarDef *vd = &fd->vars[idx];
            if (vd->scope_level != fd->scope_level)
                break;
            if (find_var(ctx, fd, vd->var_name) < 0) {
                if (add_var(ctx, fd, vd->var_name) < 0)
                    goto fail;
                vd = &fd->vars[idx]; /* fd->vars may have been reallocated */
                emit_op(s, OP_scope_get_var);
                emit_atom(s, vd->var_name);
                emit_u16(s, fd->scope_level);
                emit_op(s, OP_scope_put_var);
                emit_atom(s, vd->var_name);
                emit_u16(s, 0);
            }
            idx = vd->scope_next;
        }
        /* the argument scope has no parent, hence we don't use pop_scope(s) */
        emit_op(s, OP_leave_scope);
        emit_u16(s, fd->scope_level);
        /* set the variable scope as the current scope */
        fd->scope_level = 0;
        fd->scope_first = fd->scopes[fd->scope_level].first;
    }
    if (next_token(s))
        goto fail;
    /* generator function: yield after the parameters are evaluated */
    if (func_kind == JS_FUNC_GENERATOR ||
        func_kind == JS_FUNC_ASYNC_GENERATOR)
        emit_op(s, OP_initial_yield);
    /* in generators, yield expression is forbidden during the parsing
       of the arguments */
    fd->in_function_body = TRUE;
    push_scope(s);  /* enter body scope */
    fd->body_scope = fd->scope_level;
    if (s->token.val == TOK_ARROW) {
        if (next_token(s))
            goto fail;
        if (s->token.val != '{') {
            if (js_parse_function_check_names(s, fd, func_name))
                goto fail;
            if (js_parse_assign_expr(s))
                goto fail;
            if (func_kind != JS_FUNC_NORMAL)
                emit_op(s, OP_return_async);
            else
                emit_op(s, OP_return);
            if (!(fd->js_mode & JS_MODE_STRIP)) {
                /* save the function source code */
                /* the end of the function source code is after the last
                   token of the function source stored into s->last_ptr */
                fd->source_len = s->last_ptr - ptr;
                fd->source = js_strndup(ctx, (const char *)ptr, fd->source_len);
                if (!fd->source)
                    goto fail;
            }
            goto done;
        }
    }
    if (js_parse_expect(s, '{'))
        goto fail;
    if (js_parse_directives(s))
        goto fail;
    /* in strict_mode, check function and argument names */
    if (js_parse_function_check_names(s, fd, func_name))
        goto fail;
    while (s->token.val != '}') {
        if (js_parse_source_element(s))
            goto fail;
    }
    if (!(fd->js_mode & JS_MODE_STRIP)) {
        /* save the function source code */
        fd->source_len = s->buf_ptr - ptr;
        fd->source = js_strndup(ctx, (const char *)ptr, fd->source_len);
        if (!fd->source)
            goto fail;
    }
    if (next_token(s)) {
        /* consume the '}' */
        goto fail;
    }
    /* in case there is no return, add one */
    if (js_is_live_code(s)) {
        emit_return(s, FALSE);
    }
done:
    s->cur_func = fd->parent;
    /* create the function object */
    {
        int idx;
        JSAtom func_name = fd->func_name;
        /* the real object will be set at the end of the compilation */
        idx = cpool_add(s, JS_NULL);
        fd->parent_cpool_idx = idx;
        if (is_expr) {
            /* for constructors, no code needs to be generated here */
            if (func_type != JS_PARSE_FUNC_CLASS_CONSTRUCTOR &&
                func_type != JS_PARSE_FUNC_DERIVED_CLASS_CONSTRUCTOR) {
                /* OP_fclosure creates the function object from the bytecode
                   and adds the scope information */
                emit_op(s, OP_fclosure);
                emit_u32(s, idx);
                if (func_name == JS_ATOM_NULL) {
                    emit_op(s, OP_set_name);
                    emit_u32(s, JS_ATOM_NULL);
                }
            }
        } else if (func_type == JS_PARSE_FUNC_VAR) {
            emit_op(s, OP_fclosure);
            emit_u32(s, idx);
            if (create_func_var) {
                if (s->cur_func->is_global_var) {
                    JSGlobalVar *hf;
                    /* the global variable must be defined at the start of the
                       function */
                    hf = add_global_var(ctx, s->cur_func, func_name);
                    if (!hf)
                        goto fail;
                    /* it is considered as defined at the top level
                       (needed for annex B.3.3.4 and B.3.3.5
                       checks) */
                    hf->scope_level = 0;
                    hf->force_init = ((s->cur_func->js_mode & JS_MODE_STRICT) != 0);
                    /* store directly into global var, bypass lexical scope */
                    emit_op(s, OP_dup);
                    emit_op(s, OP_scope_put_var);
                    emit_atom(s, func_name);
                    emit_u16(s, 0);
                } else {
                    /* do not call define_var to bypass lexical scope check */
                    func_idx = find_var(ctx, s->cur_func, func_name);
                    if (func_idx < 0) {
                        func_idx = add_var(ctx, s->cur_func, func_name);
                        if (func_idx < 0)
                            goto fail;
                    }
                    /* store directly into local var, bypass lexical catch scope */
                    emit_op(s, OP_dup);
                    emit_op(s, OP_scope_put_var);
                    emit_atom(s, func_name);
                    emit_u16(s, 0);
                }
            }
            if (lexical_func_idx >= 0) {
                /* lexical variable will be initialized upon entering scope */
                s->cur_func->vars[lexical_func_idx].func_pool_idx = idx;
                emit_op(s, OP_drop);
            } else {
                /* store function object into its lexical name */
                /* XXX: could use OP_put_loc directly */
                emit_op(s, OP_scope_put_var_init);
                emit_atom(s, func_name);
                emit_u16(s, s->cur_func->scope_level);
            }
        } else {
            if (!s->cur_func->is_global_var) {
                int var_idx = define_var(s, s->cur_func, func_name, JS_VAR_DEF_VAR);
                if (var_idx < 0)
                    goto fail;
                /* the variable will be assigned at the top of the function */
                if (var_idx & ARGUMENT_VAR_OFFSET) {
                    s->cur_func->args[var_idx - ARGUMENT_VAR_OFFSET].func_pool_idx = idx;
                } else {
                    s->cur_func->vars[var_idx].func_pool_idx = idx;
                }
            } else {
                JSAtom func_var_name;
                JSGlobalVar *hf;
                if (func_name == JS_ATOM_NULL)
                    func_var_name = JS_ATOM__default_; /* export default */
                else
                    func_var_name = func_name;
                /* the variable will be assigned at the top of the function */
                hf = add_global_var(ctx, s->cur_func, func_var_name);
                if (!hf)
                    goto fail;
                hf->cpool_idx = idx;
                if (export_flag != JS_PARSE_EXPORT_NONE) {
                    if (!add_export_entry(s, s->cur_func->module, func_var_name,
                                          export_flag == JS_PARSE_EXPORT_NAMED ? func_var_name : JS_ATOM_default, JS_EXPORT_TYPE_LOCAL))
                        goto fail;
                }
            }
        }
    }
    return 0;
 fail:
    s->cur_func = fd->parent;
    js_free_function_def(ctx, fd);
    if (pfd)
        *pfd = NULL;
    return -1;
}

static __exception int js_parse_function_decl(JSParseState *s,
                                              JSParseFunctionEnum func_type,
                                              JSFunctionKindEnum func_kind,
                                              JSAtom func_name,
                                              const uint8_t *ptr,
                                              int function_line_num)
{
    return js_parse_function_decl2(s, func_type, func_kind, func_name, ptr,
                                   function_line_num, JS_PARSE_EXPORT_NONE,
                                   NULL);
}

int js_parse_program(JSParseState *s)
{
    JSFunctionDef *fd = s->cur_func;
    int idx;
    if (next_token(s))
        return -1;
    if (js_parse_directives(s))
        return -1;
    fd->is_global_var = (fd->eval_type == JS_EVAL_TYPE_GLOBAL) ||
        (fd->eval_type == JS_EVAL_TYPE_MODULE) ||
        !(fd->js_mode & JS_MODE_STRICT);
    if (!s->is_module) {
        /* hidden variable for the return value */
        fd->eval_ret_idx = idx = add_var(s->ctx, fd, JS_ATOM__ret_);
        if (idx < 0)
            return -1;
    }
    while (s->token.val != TOK_EOF) {
        if (js_parse_source_element(s))
            return -1;
    }
    if (!s->is_module) {
        /* return the value of the hidden variable eval_ret_idx  */
        emit_op(s, OP_get_loc);
        emit_u16(s, fd->eval_ret_idx);
        emit_op(s, OP_return);
    } else {
        emit_op(s, OP_return_undef);
    }
    return 0;
}