dt_parser.c

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		    ctf_array_info(lfp, lbase, &r) == 0) {
			lref = ctf_type_resolve(lfp, r.ctr_contents);
		}
	}

	if (!rp_is_int) {
		rbase = ctf_type_resolve(rfp, rp->dn_type);
		rkind = ctf_type_kind(rfp, rbase);

		if (rkind == CTF_K_POINTER) {
			rref = ctf_type_resolve(rfp,
			    ctf_type_reference(rfp, rbase));
		} else if (rkind == CTF_K_ARRAY &&
		    ctf_array_info(rfp, rbase, &r) == 0) {
			rref = ctf_type_resolve(rfp, r.ctr_contents);
		}
	}

	/*
	 * We know that one or the other type may still be a zero-valued
	 * integer constant.  To simplify the code below, set the integer
	 * type variables equal to the non-integer types and proceed.
	 */
	if (lp_is_int) {
		lbase = rbase;
		lkind = rkind;
		lref = rref;
		lfp = rfp;
	} else if (rp_is_int) {
		rbase = lbase;
		rkind = lkind;
		rref = lref;
		rfp = lfp;
	}

	lp_is_void = ctf_type_encoding(lfp, lref, &e) == 0 && IS_VOID(e);
	rp_is_void = ctf_type_encoding(rfp, rref, &e) == 0 && IS_VOID(e);

	/*
	 * The types are compatible if both are pointers to the same type, or
	 * if either pointer is a void pointer.  If they are compatible, set
	 * tp to point to the more specific pointer type and return it.
	 */
	compat = (lkind == CTF_K_POINTER || lkind == CTF_K_ARRAY) &&
	    (rkind == CTF_K_POINTER || rkind == CTF_K_ARRAY) &&
	    (lp_is_void || rp_is_void || ctf_type_compat(lfp, lref, rfp, rref));

	if (compat) {
		if (fpp != NULL)
			*fpp = rp_is_void ? lfp : rfp;
		if (tp != NULL)
			*tp = rp_is_void ? lbase : rbase;
	}

	return (compat);
}

/*
 * The rules for checking argument types against parameter types are described
 * in the ANSI-C spec (see K&R[A7.3.2] and K&R[A7.17]).  We use the same rule
 * set to determine whether associative array arguments match the prototype.
 */
int
dt_node_is_argcompat(const dt_node_t *lp, const dt_node_t *rp)
{
	ctf_file_t *lfp = lp->dn_ctfp;
	ctf_file_t *rfp = rp->dn_ctfp;

	assert(lp->dn_flags & DT_NF_COOKED);
	assert(rp->dn_flags & DT_NF_COOKED);

	if (dt_node_is_integer(lp) && dt_node_is_integer(rp))
		return (1); /* integer types are compatible */

	if (dt_node_is_strcompat(lp) && dt_node_is_strcompat(rp))
		return (1); /* string types are compatible */

	if (dt_node_is_stack(lp) && dt_node_is_stack(rp))
		return (1); /* stack types are compatible */

	switch (ctf_type_kind(lfp, ctf_type_resolve(lfp, lp->dn_type))) {
	case CTF_K_FUNCTION:
	case CTF_K_STRUCT:
	case CTF_K_UNION:
		return (ctf_type_compat(lfp, lp->dn_type, rfp, rp->dn_type));
	default:
		return (dt_node_is_ptrcompat(lp, rp, NULL, NULL));
	}
}

/*
 * We provide dt_node_is_posconst() as a convenience routine for callers who
 * wish to verify that an argument is a positive non-zero integer constant.
 */
int
dt_node_is_posconst(const dt_node_t *dnp)
{
	return (dnp->dn_kind == DT_NODE_INT && dnp->dn_value != 0 && (
	    (dnp->dn_flags & DT_NF_SIGNED) == 0 || (int64_t)dnp->dn_value > 0));
}

int
dt_node_is_actfunc(const dt_node_t *dnp)
{
	return (dnp->dn_kind == DT_NODE_FUNC &&
	    dnp->dn_ident->di_kind == DT_IDENT_ACTFUNC);
}

/*
 * The original rules for integer constant typing are described in K&R[A2.5.1].
 * However, since we support long long, we instead use the rules from ISO C99
 * clause 6.4.4.1 since that is where long longs are formally described.  The
 * rules require us to know whether the constant was specified in decimal or
 * in octal or hex, which we do by looking at our lexer's 'yyintdecimal' flag.
 * The type of an integer constant is the first of the corresponding list in
 * which its value can be represented:
 *
 * unsuffixed decimal:   int, long, long long
 * unsuffixed oct/hex:   int, unsigned int, long, unsigned long,
 *                       long long, unsigned long long
 * suffix [uU]:          unsigned int, unsigned long, unsigned long long
 * suffix [lL] decimal:  long, long long
 * suffix [lL] oct/hex:  long, unsigned long, long long, unsigned long long
 * suffix [uU][Ll]:      unsigned long, unsigned long long
 * suffix ll/LL decimal: long long
 * suffix ll/LL oct/hex: long long, unsigned long long
 * suffix [uU][ll/LL]:   unsigned long long
 *
 * Given that our lexer has already validated the suffixes by regexp matching,
 * there is an obvious way to concisely encode these rules: construct an array
 * of the types in the order int, unsigned int, long, unsigned long, long long,
 * unsigned long long.  Compute an integer array starting index based on the
 * suffix (e.g. none = 0, u = 1, ull = 5), and compute an increment based on
 * the specifier (dec/oct/hex) and suffix (u).  Then iterate from the starting
 * index to the end, advancing using the increment, and searching until we
 * find a limit that matches or we run out of choices (overflow).  To make it
 * even faster, we precompute the table of type information in dtrace_open().
 */
dt_node_t *
dt_node_int(uintmax_t value)
{
	dt_node_t *dnp = dt_node_alloc(DT_NODE_INT);
	dtrace_hdl_t *dtp = yypcb->pcb_hdl;

	int n = (yyintdecimal | (yyintsuffix[0] == 'u')) + 1;
	int i = 0;

	const char *p;
	char c;

	dnp->dn_op = DT_TOK_INT;
	dnp->dn_value = value;

	for (p = yyintsuffix; (c = *p) != '\0'; p++) {
		if (c == 'U' || c == 'u')
			i += 1;
		else if (c == 'L' || c == 'l')
			i += 2;
	}

	for (; i < sizeof (dtp->dt_ints) / sizeof (dtp->dt_ints[0]); i += n) {
		if (value <= dtp->dt_ints[i].did_limit) {
			dt_node_type_assign(dnp,
			    dtp->dt_ints[i].did_ctfp,
			    dtp->dt_ints[i].did_type);

			/*
			 * If a prefix character is present in macro text, add
			 * in the corresponding operator node (see dt_lex.l).
			 */
			switch (yyintprefix) {
			case '+':
				return (dt_node_op1(DT_TOK_IPOS, dnp));
			case '-':
				return (dt_node_op1(DT_TOK_INEG, dnp));
			default:
				return (dnp);
			}
		}
	}

	xyerror(D_INT_OFLOW, "integer constant 0x%llx cannot be represented "
	    "in any built-in integral type\n", (u_longlong_t)value);
	/*NOTREACHED*/
	return (NULL);		/* keep gcc happy */
}

dt_node_t *
dt_node_string(char *string)
{
	dtrace_hdl_t *dtp = yypcb->pcb_hdl;
	dt_node_t *dnp;

	if (string == NULL)
		longjmp(yypcb->pcb_jmpbuf, EDT_NOMEM);

	dnp = dt_node_alloc(DT_NODE_STRING);
	dnp->dn_op = DT_TOK_STRING;
	dnp->dn_string = string;
	dt_node_type_assign(dnp, DT_STR_CTFP(dtp), DT_STR_TYPE(dtp));

	return (dnp);
}

dt_node_t *
dt_node_ident(char *name)
{
	dtrace_hdl_t *dtp = yypcb->pcb_hdl;
	dt_ident_t *idp;
	dt_node_t *dnp;

	if (name == NULL)
		longjmp(yypcb->pcb_jmpbuf, EDT_NOMEM);

	/*
	 * If the identifier is an inlined integer constant, then create an INT
	 * node that is a clone of the inline parse tree node and return that
	 * immediately, allowing this inline to be used in parsing contexts
	 * that require constant expressions (e.g. scalar array sizes).
	 */
	if ((idp = dt_idhash_lookup(dtp->dt_globals, name)) != NULL &&
	    (idp->di_flags & DT_IDFLG_INLINE)) {
		dt_idnode_t *inp = idp->di_data;

		if (inp->din_root->dn_kind == DT_NODE_INT) {
			free(name);

			dnp = dt_node_alloc(DT_NODE_INT);
			dnp->dn_op = DT_TOK_INT;
			dnp->dn_value = inp->din_root->dn_value;
			dt_node_type_propagate(inp->din_root, dnp);

			return (dnp);
		}
	}

	dnp = dt_node_alloc(DT_NODE_IDENT);
	dnp->dn_op = name[0] == '@' ? DT_TOK_AGG : DT_TOK_IDENT;
	dnp->dn_string = name;

	return (dnp);
}

/*
 * Create an empty node of type corresponding to the given declaration.
 * Explicit references to user types (C or D) are assigned the default
 * stability; references to other types are _dtrace_typattr (Private).
 */
dt_node_t *
dt_node_type(dt_decl_t *ddp)
{
	dtrace_hdl_t *dtp = yypcb->pcb_hdl;
	dtrace_typeinfo_t dtt;
	dt_node_t *dnp;
	char *name = NULL;
	int err;

	/*
	 * If 'ddp' is NULL, we get a decl by popping the decl stack.  This
	 * form of dt_node_type() is used by parameter rules in dt_grammar.y.
	 */
	if (ddp == NULL)
		ddp = dt_decl_pop_param(&name);

	err = dt_decl_type(ddp, &dtt);
	dt_decl_free(ddp);

	if (err != 0) {
		free(name);
		longjmp(yypcb->pcb_jmpbuf, EDT_COMPILER);
	}

	dnp = dt_node_alloc(DT_NODE_TYPE);
	dnp->dn_op = DT_TOK_IDENT;
	dnp->dn_string = name;
	dt_node_type_assign(dnp, dtt.dtt_ctfp, dtt.dtt_type);

	if (dtt.dtt_ctfp == dtp->dt_cdefs->dm_ctfp ||
	    dtt.dtt_ctfp == dtp->dt_ddefs->dm_ctfp)
		dt_node_attr_assign(dnp, _dtrace_defattr);
	else
		dt_node_attr_assign(dnp, _dtrace_typattr);

	return (dnp);
}

/*
 * Create a type node corresponding to a varargs (...) parameter by just
 * assigning it type CTF_ERR.  The decl processing code will handle this.
 */
dt_node_t *
dt_node_vatype(void)
{
	dt_node_t *dnp = dt_node_alloc(DT_NODE_TYPE);

	dnp->dn_op = DT_TOK_IDENT;
	dnp->dn_ctfp = NULL;
	dnp->dn_type = CTF_ERR;
	dnp->dn_attr = _dtrace_defattr;

	return (dnp);
}

/*
 * Instantiate a decl using the contents of the current declaration stack.  As
 * we do not currently permit decls to be initialized, this function currently
 * returns NULL and no parse node is created.  When this function is called,
 * the topmost scope's ds_ident pointer will be set to NULL (indicating no
 * init_declarator rule was matched) or will point to the identifier to use.
 */
dt_node_t *
dt_node_decl(void)
{
	dtrace_hdl_t *dtp = yypcb->pcb_hdl;
	dt_scope_t *dsp = &yypcb->pcb_dstack;
	dt_dclass_t class = dsp->ds_class;
	dt_decl_t *ddp = dt_decl_top();

	dt_module_t *dmp;
	dtrace_typeinfo_t dtt;
	ctf_id_t type;

	char n1[DT_TYPE_NAMELEN];
	char n2[DT_TYPE_NAMELEN];

	if (dt_decl_type(ddp, &dtt) != 0)
		longjmp(yypcb->pcb_jmpbuf, EDT_COMPILER);

	/*
	 * If we have no declaration identifier, then this is either a spurious
	 * declaration of an intrinsic type (e.g. "extern int;") or declaration
	 * or redeclaration of a struct, union, or enum type or tag.
	 */
	if (dsp->ds_ident == NULL) {
		if (ddp->dd_kind != CTF_K_STRUCT &&
		    ddp->dd_kind != CTF_K_UNION && ddp->dd_kind != CTF_K_ENUM)
			xyerror(D_DECL_USELESS, "useless declaration\n");

		dt_dprintf("type %s added as id %ld\n", dt_type_name(
		    ddp->dd_ctfp, ddp->dd_type, n1, sizeof (n1)), ddp->dd_type);

		return (NULL);
	}

	if (strchr(dsp->ds_ident, '`') != NULL) {
		xyerror(D_DECL_SCOPE, "D scoping operator may not be used in "
		    "a declaration name (%s)\n", dsp->ds_ident);
	}

	/*
	 * If we are nested inside of a C include file, add the declaration to
	 * the C definition module; otherwise use the D definition module.
	 */
	if (yypcb->pcb_idepth != 0)
		dmp = dtp->dt_cdefs;
	else
		dmp = dtp->dt_ddefs;

	/*
	 * If we see a global or static declaration of a function prototype,
	 * treat this as equivalent to a D extern declaration.
	 */
	if (ctf_type_kind(dtt.dtt_ctfp, dtt.dtt_type) == CTF_K_FUNCTION &&
	    (class == DT_DC_DEFAULT || class == DT_DC_STATIC))
		class = DT_DC_EXTERN;

	switch (class) {
	case DT_DC_AUTO:
	case DT_DC_REGISTER:
	case DT_DC_STATIC:
		xyerror(D_DECL_BADCLASS, "specified storage class not "
		    "appropriate in D\n");
		/*NOTREACHED*/

	case DT_DC_EXTERN: {
		dtrace_typeinfo_t ott;
		dtrace_syminfo_t dts;
		GElf_Sym sym;

		int exists = dtrace_lookup_by_name(dtp,
		    dmp->dm_name, dsp->ds_ident, &sym, &dts) == 0;

		if (exists && (dtrace_symbol_type(dtp, &sym, &dts, &ott) != 0 ||
		    ctf_type_cmp(dtt.dtt_ctfp, dtt.dtt_type,
		    ott.dtt_ctfp, ott.dtt_type) != 0)) {
			xyerror(D_DECL_IDRED, "identifier redeclared: %s`%s\n"
			    "\t current: %s\n\tprevious: %s\n",
			    dmp->dm_name, dsp->ds_ident,
			    dt_type_name(dtt.dtt_ctfp, dtt.dtt_type,
				n1, sizeof (n1)),
			    dt_type_name(ott.dtt_ctfp, ott.dtt_type,
				n2, sizeof (n2)));
		} else if (!exists && dt_module_extern(dtp, dmp,
		    dsp->ds_ident, &dtt) == NULL) {
			xyerror(D_UNKNOWN,
			    "failed to extern %s: %s\n", dsp->ds_ident,
			    dtrace_errmsg(dtp, dtrace_errno(dtp)));
		} else {
			dt_dprintf("extern %s`%s type=<%s>\n",
			    dmp->dm_name, dsp->ds_ident,
			    dt_type_name(dtt.dtt_ctfp, dtt.dtt_type,
				n1, sizeof (n1)));
		}
		break;
	}

	case DT_DC_TYPEDEF:
		/*
		 * If the source type for the typedef is not defined in the
		 * target container or its parent, copy the type to the target
		 * container and reset dtt_ctfp and dtt_type to the copy.
		 */
		if (dtt.dtt_ctfp != dmp->dm_ctfp &&
		    dtt.dtt_ctfp != ctf_parent_file(dmp->dm_ctfp)) {

			dtt.dtt_type = ctf_add_type(dmp->dm_ctfp,
			    dtt.dtt_ctfp, dtt.dtt_type);
			dtt.dtt_ctfp = dmp->dm_ctfp;

			if (dtt.dtt_type == CTF_ERR ||
			    ctf_update(dtt.dtt_ctfp) == CTF_ERR) {
				xyerror(D_UNKNOWN, "failed to copy typedef %s "
				    "source type: %s\n", dsp->ds_ident,
				    ctf_errmsg(ctf_errno(dtt.dtt_ctfp)));
			}
		}

		type = ctf_add_typedef(dmp->dm_ctfp,
		    CTF_ADD_ROOT, dsp->ds_ident, dtt.dtt_type);

		if (type == CTF_ERR || ctf_update(dmp->dm_ctfp) == CTF_ERR) {
			xyerror(D_UNKNOWN, "failed to typedef %s: %s\n",
			    dsp->ds_ident, ctf_errmsg(ctf_errno(dmp->dm_ctfp)));
		}

		dt_dprintf("typedef %s added as id %ld\n", dsp->ds_ident, type);
		break;

	default: {
		ctf_encoding_t cte;
		dt_idhash_t *dhp;
		dt_ident_t *idp;
		dt_node_t idn;
		int assc, idkind;
		uint_t id, kind;
		ushort_t idflags;

		switch (class) {
		case DT_DC_THIS:
			dhp = yypcb->pcb_locals;
			idflags = DT_IDFLG_LOCAL;
			break;
		case DT_DC_SELF:
			dhp = dtp->dt_tls;
			idflags = DT_IDFLG_TLS;
			break;
		default:
			dhp = dtp->dt_globals;
			idflags = 0;
			break;
		}

		if (ddp->dd_kind == CTF_K_ARRAY && ddp->dd_node == NULL) {
			xyerror(D_DECL_ARRNULL,
			    "array declaration requires array dimension or "
			    "tuple signature: %s\n", dsp->ds_ident);
		}

		/*
		 * Create a fake dt_node_t on the stack so we can determine the
		 * type of the ident if it's defined.  We look it up in the
		 * appropriate hash table (dhp) and cook it into the node (idn).
		 */