jsparse.h

Swfdec still is development software, but has also followed a rigid no-crashes-allowed policy. I b

 *                          if #n=primary for function, paren, name, object
 *                          literal expressions
 * TOK_USESHARP nullary     pn_num: jsint value of n in #n#
 * TOK_RP       unary       pn_kid: parenthesized expression
 * TOK_NAME,    name        pn_atom: name, string, or object atom
 * TOK_STRING,              pn_op: JSOP_NAME, JSOP_STRING, or JSOP_OBJECT
 * TOK_OBJECT               If JSOP_NAME, pn_op may be JSOP_*ARG or JSOP_*VAR
 *                          with pn_slot >= 0 and pn_attrs telling const-ness
 * TOK_NUMBER   dval        pn_dval: double value of numeric literal
 * TOK_PRIMARY  nullary     pn_op: JSOp bytecode
 */
typedef enum JSParseNodeArity {
    PN_FUNC     = -3,
    PN_LIST     = -2,
    PN_TERNARY  =  3,
    PN_BINARY   =  2,
    PN_UNARY    =  1,
    PN_NAME     = -1,
    PN_NULLARY  =  0
} JSParseNodeArity;

struct JSParseNode {
    JSTokenType         pn_type;
    JSTokenPos          pn_pos;
    JSOp                pn_op;
    ptrdiff_t           pn_offset;      /* first generated bytecode offset */
    JSParseNodeArity    pn_arity;
    union {
        struct {                        /* TOK_FUNCTION node */
            JSAtom      *funAtom;       /* atomized function object */
            JSParseNode *body;          /* TOK_LC list of statements */
            uint32      flags;          /* accumulated tree context flags */
            uint32      tryCount;       /* count of try statements in body */
        } func;
        struct {                        /* list of next-linked nodes */
            JSParseNode *head;          /* first node in list */
            JSParseNode **tail;         /* ptr to ptr to last node in list */
            uint32      count;          /* number of nodes in list */
            uint32      extra;          /* extra comma flag for [1,2,,] */
        } list;
        struct {                        /* ternary: if, for(;;), ?: */
            JSParseNode *kid1;          /* condition, discriminant, etc. */
            JSParseNode *kid2;          /* then-part, case list, etc. */
            JSParseNode *kid3;          /* else-part, default case, etc. */
        } ternary;
        struct {                        /* two kids if binary */
            JSParseNode *left;
            JSParseNode *right;
            jsval       val;            /* switch case value */
        } binary;
        struct {                        /* one kid if unary */
            JSParseNode *kid;
            jsint       num;            /* -1 or sharp variable number */
        } unary;
        struct {                        /* name, labeled statement, etc. */
            JSAtom      *atom;          /* name or label atom, null if slot */
            JSParseNode *expr;          /* object or initializer */
            jsint       slot;           /* -1 or arg or local var slot */
            uintN       attrs;          /* attributes if local var or const */
        } name;
        jsdouble        dval;           /* aligned numeric literal value */
    } pn_u;
    JSParseNode         *pn_next;       /* to align dval and pn_u on RISCs */
};

#define pn_funAtom      pn_u.func.funAtom
#define pn_body         pn_u.func.body
#define pn_flags        pn_u.func.flags
#define pn_tryCount     pn_u.func.tryCount
#define pn_head         pn_u.list.head
#define pn_tail         pn_u.list.tail
#define pn_count        pn_u.list.count
#define pn_extra        pn_u.list.extra
#define pn_kid1         pn_u.ternary.kid1
#define pn_kid2         pn_u.ternary.kid2
#define pn_kid3         pn_u.ternary.kid3
#define pn_left         pn_u.binary.left
#define pn_right        pn_u.binary.right
#define pn_val          pn_u.binary.val
#define pn_kid          pn_u.unary.kid
#define pn_num          pn_u.unary.num
#define pn_atom         pn_u.name.atom
#define pn_expr         pn_u.name.expr
#define pn_slot         pn_u.name.slot
#define pn_attrs        pn_u.name.attrs
#define pn_dval         pn_u.dval

/* PN_LIST pn_extra flags. */
#define PNX_STRCAT      0x01            /* TOK_PLUS list has string term */
#define PNX_CANTFOLD    0x02            /* TOK_PLUS list has unfoldable term */
#define PNX_POPVAR      0x04            /* TOK_VAR last result needs popping */
#define PNX_FORINVAR    0x08            /* TOK_VAR is left kid of TOK_IN node,
                                           which is left kid of TOK_FOR */
#define PNX_ENDCOMMA    0x10            /* array literal has comma at end */

/*
 * Move pn2 into pn, preserving pn->pn_pos and pn->pn_offset and handing off
 * any kids in pn2->pn_u, by clearing pn2.
 */
#define PN_MOVE_NODE(pn, pn2)                                                 \
    JS_BEGIN_MACRO                                                            \
        (pn)->pn_type = (pn2)->pn_type;                                       \
        (pn)->pn_op = (pn2)->pn_op;                                           \
        (pn)->pn_arity = (pn2)->pn_arity;                                     \
        (pn)->pn_u = (pn2)->pn_u;                                             \
        PN_CLEAR_NODE(pn2);                                                   \
    JS_END_MACRO

#define PN_CLEAR_NODE(pn)                                                     \
    JS_BEGIN_MACRO                                                            \
        (pn)->pn_type = TOK_EOF;                                              \
        (pn)->pn_op = JSOP_NOP;                                               \
        (pn)->pn_arity = PN_NULLARY;                                          \
    JS_END_MACRO

/* True if pn is a parsenode representing a literal constant. */
#define PN_IS_CONSTANT(pn)                                                    \
    ((pn)->pn_type == TOK_NUMBER ||                                           \
     (pn)->pn_type == TOK_STRING ||                                           \
     ((pn)->pn_type == TOK_PRIMARY && (pn)->pn_op != JSOP_THIS))

/*
 * Compute a pointer to the last JSParseNode element in a singly-linked list.
 * NB: list must be non-empty for correct PN_LAST usage!
 */
#define PN_LAST(list) \
    ((JSParseNode *)((char *)(list)->pn_tail - offsetof(JSParseNode, pn_next)))

#define PN_INIT_LIST(list)                                                    \
    JS_BEGIN_MACRO                                                            \
        (list)->pn_head = NULL;                                               \
        (list)->pn_tail = &(list)->pn_head;                                   \
        (list)->pn_count = 0;                                                 \
    JS_END_MACRO

#define PN_INIT_LIST_1(list, pn)                                              \
    JS_BEGIN_MACRO                                                            \
        (list)->pn_head = (pn);                                               \
        (list)->pn_tail = &(pn)->pn_next;                                     \
        (list)->pn_count = 1;                                                 \
    JS_END_MACRO

#define PN_APPEND(list, pn)                                                   \
    JS_BEGIN_MACRO                                                            \
        *(list)->pn_tail = (pn);                                              \
        (list)->pn_tail = &(pn)->pn_next;                                     \
        (list)->pn_count++;                                                   \
    JS_END_MACRO

/*
 * Parse a top-level JS script.
 *
 * The caller must prevent the GC from running while this function is active,
 * because atoms and function newborns are not rooted yet.
 */
extern JS_FRIEND_API(JSParseNode *)
js_ParseTokenStream(JSContext *cx, JSObject *chain, JSTokenStream *ts);

extern JS_FRIEND_API(JSBool)
js_CompileTokenStream(JSContext *cx, JSObject *chain, JSTokenStream *ts,
                      JSCodeGenerator *cg);

extern JSBool
js_CompileFunctionBody(JSContext *cx, JSTokenStream *ts, JSFunction *fun);

extern JSBool
js_FoldConstants(JSContext *cx, JSParseNode *pn, JSTreeContext *tc);

JS_END_EXTERN_C

#endif /* jsparse_h___ */