1 /* Generate information regarding function declarations and definitions based
2 on information stored in GCC's tree structure. This code implements the
4 Copyright (C) 1989, 1991, 1994, 1995, 1997, 1998,
5 1999, 2000 Free Software Foundation, Inc.
6 Contributed by Ron Guilmette (rfg@segfault.us.com).
8 This file is part of GCC.
10 GCC is free software; you can redistribute it and/or modify it under
11 the terms of the GNU General Public License as published by the Free
12 Software Foundation; either version 2, or (at your option) any later
15 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
16 WARRANTY; without even the implied warranty of MERCHANTABILITY or
17 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
20 You should have received a copy of the GNU General Public License
21 along with GCC; see the file COPYING. If not, write to the Free
22 Software Foundation, 59 Temple Place - Suite 330, Boston, MA
32 enum formals_style_enum {
37 typedef enum formals_style_enum formals_style;
40 static const char *data_type;
42 static char *affix_data_type PARAMS ((const char *));
43 static const char *gen_formal_list_for_type PARAMS ((tree, formals_style));
44 static int deserves_ellipsis PARAMS ((tree));
45 static const char *gen_formal_list_for_func_def PARAMS ((tree, formals_style));
46 static const char *gen_type PARAMS ((const char *, tree, formals_style));
47 static const char *gen_decl PARAMS ((tree, int, formals_style));
49 /* Given a string representing an entire type or an entire declaration
50 which only lacks the actual "data-type" specifier (at its left end),
51 affix the data-type specifier to the left end of the given type
52 specification or object declaration.
54 Because of C language weirdness, the data-type specifier (which normally
55 goes in at the very left end) may have to be slipped in just to the
56 right of any leading "const" or "volatile" qualifiers (there may be more
57 than one). Actually this may not be strictly necessary because it seems
58 that GCC (at least) accepts `<data-type> const foo;' and treats it the
59 same as `const <data-type> foo;' but people are accustomed to seeing
60 `const char *foo;' and *not* `char const *foo;' so we try to create types
61 that look as expected. */
64 affix_data_type (param)
67 char *const type_or_decl = ASTRDUP (param);
68 char *p = type_or_decl;
69 char *qualifiers_then_data_type;
72 /* Skip as many leading const's or volatile's as there are. */
76 if (!strncmp (p, "volatile ", 9))
81 if (!strncmp (p, "const ", 6))
89 /* p now points to the place where we can insert the data type. We have to
90 add a blank after the data-type of course. */
92 if (p == type_or_decl)
93 return concat (data_type, " ", type_or_decl, NULL);
97 qualifiers_then_data_type = concat (type_or_decl, data_type, NULL);
99 return concat (qualifiers_then_data_type, " ", p, NULL);
102 /* Given a tree node which represents some "function type", generate the
103 source code version of a formal parameter list (of some given style) for
104 this function type. Return the whole formal parameter list (including
105 a pair of surrounding parens) as a string. Note that if the style
106 we are currently aiming for is non-ansi, then we just return a pair
107 of empty parens here. */
110 gen_formal_list_for_type (fntype, style)
114 const char *formal_list = "";
120 formal_type = TYPE_ARG_TYPES (fntype);
121 while (formal_type && TREE_VALUE (formal_type) != void_type_node)
123 const char *this_type;
126 formal_list = concat (formal_list, ", ", NULL);
128 this_type = gen_type ("", TREE_VALUE (formal_type), ansi);
130 = ((strlen (this_type))
131 ? concat (formal_list, affix_data_type (this_type), NULL)
132 : concat (formal_list, data_type, NULL));
134 formal_type = TREE_CHAIN (formal_type);
137 /* If we got to here, then we are trying to generate an ANSI style formal
140 New style prototyped ANSI formal parameter lists should in theory always
141 contain some stuff between the opening and closing parens, even if it is
144 The brutal truth though is that there is lots of old K&R code out there
145 which contains declarations of "pointer-to-function" parameters and
146 these almost never have fully specified formal parameter lists associated
147 with them. That is, the pointer-to-function parameters are declared
148 with just empty parameter lists.
150 In cases such as these, protoize should really insert *something* into
151 the vacant parameter lists, but what? It has no basis on which to insert
152 anything in particular.
154 Here, we make life easy for protoize by trying to distinguish between
155 K&R empty parameter lists and new-style prototyped parameter lists
156 that actually contain "void". In the latter case we (obviously) want
157 to output the "void" verbatim, and that what we do. In the former case,
158 we do our best to give protoize something nice to insert.
160 This "something nice" should be something that is still valid (when
161 re-compiled) but something that can clearly indicate to the user that
162 more typing information (for the parameter list) should be added (by
163 hand) at some convenient moment.
165 The string chosen here is a comment with question marks in it. */
169 if (TYPE_ARG_TYPES (fntype))
170 /* assert (TREE_VALUE (TYPE_ARG_TYPES (fntype)) == void_type_node); */
171 formal_list = "void";
173 formal_list = "/* ??? */";
177 /* If there were at least some parameters, and if the formals-types-list
178 petered out to a NULL (i.e. without being terminated by a
179 void_type_node) then we need to tack on an ellipsis. */
181 formal_list = concat (formal_list, ", ...", NULL);
184 return concat (" (", formal_list, ")", NULL);
187 /* For the generation of an ANSI prototype for a function definition, we have
188 to look at the formal parameter list of the function's own "type" to
189 determine if the function's formal parameter list should end with an
190 ellipsis. Given a tree node, the following function will return non-zero
191 if the "function type" parameter list should end with an ellipsis. */
194 deserves_ellipsis (fntype)
199 formal_type = TYPE_ARG_TYPES (fntype);
200 while (formal_type && TREE_VALUE (formal_type) != void_type_node)
201 formal_type = TREE_CHAIN (formal_type);
203 /* If there were at least some parameters, and if the formals-types-list
204 petered out to a NULL (i.e. without being terminated by a void_type_node)
205 then we need to tack on an ellipsis. */
207 return (!formal_type && TYPE_ARG_TYPES (fntype));
210 /* Generate a parameter list for a function definition (in some given style).
212 Note that this routine has to be separate (and different) from the code that
213 generates the prototype parameter lists for function declarations, because
214 in the case of a function declaration, all we have to go on is a tree node
215 representing the function's own "function type". This can tell us the types
216 of all of the formal parameters for the function, but it cannot tell us the
217 actual *names* of each of the formal parameters. We need to output those
218 parameter names for each function definition.
220 This routine gets a pointer to a tree node which represents the actual
221 declaration of the given function, and this DECL node has a list of formal
222 parameter (variable) declarations attached to it. These formal parameter
223 (variable) declaration nodes give us the actual names of the formal
224 parameters for the given function definition.
226 This routine returns a string which is the source form for the entire
227 function formal parameter list. */
230 gen_formal_list_for_func_def (fndecl, style)
234 const char *formal_list = "";
237 formal_decl = DECL_ARGUMENTS (fndecl);
240 const char *this_formal;
242 if (*formal_list && ((style == ansi) || (style == k_and_r_names)))
243 formal_list = concat (formal_list, ", ", NULL);
244 this_formal = gen_decl (formal_decl, 0, style);
245 if (style == k_and_r_decls)
246 formal_list = concat (formal_list, this_formal, "; ", NULL);
248 formal_list = concat (formal_list, this_formal, NULL);
249 formal_decl = TREE_CHAIN (formal_decl);
253 if (!DECL_ARGUMENTS (fndecl))
254 formal_list = concat (formal_list, "void", NULL);
255 if (deserves_ellipsis (TREE_TYPE (fndecl)))
256 formal_list = concat (formal_list, ", ...", NULL);
258 if ((style == ansi) || (style == k_and_r_names))
259 formal_list = concat (" (", formal_list, ")", NULL);
263 /* Generate a string which is the source code form for a given type (t). This
264 routine is ugly and complex because the C syntax for declarations is ugly
265 and complex. This routine is straightforward so long as *no* pointer types,
266 array types, or function types are involved.
268 In the simple cases, this routine will return the (string) value which was
269 passed in as the "ret_val" argument. Usually, this starts out either as an
270 empty string, or as the name of the declared item (i.e. the formal function
273 This routine will also return with the global variable "data_type" set to
274 some string value which is the "basic" data-type of the given complete type.
275 This "data_type" string can be concatenated onto the front of the returned
276 string after this routine returns to its caller.
278 In complicated cases involving pointer types, array types, or function
279 types, the C declaration syntax requires an "inside out" approach, i.e. if
280 you have a type which is a "pointer-to-function" type, you need to handle
281 the "pointer" part first, but it also has to be "innermost" (relative to
282 the declaration stuff for the "function" type). Thus, is this case, you
283 must prepend a "(*" and append a ")" to the name of the item (i.e. formal
284 variable). Then you must append and prepend the other info for the
285 "function type" part of the overall type.
287 To handle the "innermost precedence" rules of complicated C declarators, we
288 do the following (in this routine). The input parameter called "ret_val"
289 is treated as a "seed". Each time gen_type is called (perhaps recursively)
290 some additional strings may be appended or prepended (or both) to the "seed"
291 string. If yet another (lower) level of the GCC tree exists for the given
292 type (as in the case of a pointer type, an array type, or a function type)
293 then the (wrapped) seed is passed to a (recursive) invocation of gen_type()
294 this recursive invocation may again "wrap" the (new) seed with yet more
295 declarator stuff, by appending, prepending (or both). By the time the
296 recursion bottoms out, the "seed value" at that point will have a value
297 which is (almost) the complete source version of the declarator (except
298 for the data_type info). Thus, this deepest "seed" value is simply passed
299 back up through all of the recursive calls until it is given (as the return
300 value) to the initial caller of the gen_type() routine. All that remains
301 to do at this point is for the initial caller to prepend the "data_type"
302 string onto the returned "seed". */
305 gen_type (ret_val, t, style)
312 /* If there is a typedef name for this type, use it. */
313 if (TYPE_NAME (t) && TREE_CODE (TYPE_NAME (t)) == TYPE_DECL)
314 data_type = IDENTIFIER_POINTER (DECL_NAME (TYPE_NAME (t)));
317 switch (TREE_CODE (t))
320 if (TYPE_READONLY (t))
321 ret_val = concat ("const ", ret_val, NULL);
322 if (TYPE_VOLATILE (t))
323 ret_val = concat ("volatile ", ret_val, NULL);
325 ret_val = concat ("*", ret_val, NULL);
327 if (TREE_CODE (TREE_TYPE (t)) == ARRAY_TYPE || TREE_CODE (TREE_TYPE (t)) == FUNCTION_TYPE)
328 ret_val = concat ("(", ret_val, ")", NULL);
330 ret_val = gen_type (ret_val, TREE_TYPE (t), style);
335 if (!COMPLETE_TYPE_P (t) || TREE_CODE (TYPE_SIZE (t)) != INTEGER_CST)
336 ret_val = gen_type (concat (ret_val, "[]", NULL),
337 TREE_TYPE (t), style);
338 else if (int_size_in_bytes (t) == 0)
339 ret_val = gen_type (concat (ret_val, "[0]", NULL),
340 TREE_TYPE (t), style);
343 int size = (int_size_in_bytes (t) / int_size_in_bytes (TREE_TYPE (t)));
345 sprintf (buff, "[%d]", size);
346 ret_val = gen_type (concat (ret_val, buff, NULL),
347 TREE_TYPE (t), style);
352 ret_val = gen_type (concat (ret_val,
353 gen_formal_list_for_type (t, style),
355 TREE_TYPE (t), style);
358 case IDENTIFIER_NODE:
359 data_type = IDENTIFIER_POINTER (t);
362 /* The following three cases are complicated by the fact that a
363 user may do something really stupid, like creating a brand new
364 "anonymous" type specification in a formal argument list (or as
365 part of a function return type specification). For example:
367 int f (enum { red, green, blue } color);
369 In such cases, we have no name that we can put into the prototype
370 to represent the (anonymous) type. Thus, we have to generate the
371 whole darn type specification. Yuck! */
375 data_type = IDENTIFIER_POINTER (TYPE_NAME (t));
379 chain_p = TYPE_FIELDS (t);
382 data_type = concat (data_type, gen_decl (chain_p, 0, ansi),
384 chain_p = TREE_CHAIN (chain_p);
385 data_type = concat (data_type, "; ", NULL);
387 data_type = concat ("{ ", data_type, "}", NULL);
389 data_type = concat ("struct ", data_type, NULL);
394 data_type = IDENTIFIER_POINTER (TYPE_NAME (t));
398 chain_p = TYPE_FIELDS (t);
401 data_type = concat (data_type, gen_decl (chain_p, 0, ansi),
403 chain_p = TREE_CHAIN (chain_p);
404 data_type = concat (data_type, "; ", NULL);
406 data_type = concat ("{ ", data_type, "}", NULL);
408 data_type = concat ("union ", data_type, NULL);
413 data_type = IDENTIFIER_POINTER (TYPE_NAME (t));
417 chain_p = TYPE_VALUES (t);
420 data_type = concat (data_type,
421 IDENTIFIER_POINTER (TREE_PURPOSE (chain_p)), NULL);
422 chain_p = TREE_CHAIN (chain_p);
424 data_type = concat (data_type, ", ", NULL);
426 data_type = concat ("{ ", data_type, " }", NULL);
428 data_type = concat ("enum ", data_type, NULL);
432 data_type = IDENTIFIER_POINTER (DECL_NAME (t));
436 data_type = IDENTIFIER_POINTER (DECL_NAME (TYPE_NAME (t)));
437 /* Normally, `unsigned' is part of the deal. Not so if it comes
438 with a type qualifier. */
439 if (TREE_UNSIGNED (t) && TYPE_QUALS (t))
440 data_type = concat ("unsigned ", data_type, NULL);
444 data_type = IDENTIFIER_POINTER (DECL_NAME (TYPE_NAME (t)));
452 data_type = "[ERROR]";
459 if (TYPE_READONLY (t))
460 ret_val = concat ("const ", ret_val, NULL);
461 if (TYPE_VOLATILE (t))
462 ret_val = concat ("volatile ", ret_val, NULL);
463 if (TYPE_RESTRICT (t))
464 ret_val = concat ("restrict ", ret_val, NULL);
468 /* Generate a string (source) representation of an entire entity declaration
469 (using some particular style for function types).
471 The given entity may be either a variable or a function.
473 If the "is_func_definition" parameter is non-zero, assume that the thing
474 we are generating a declaration for is a FUNCTION_DECL node which is
475 associated with a function definition. In this case, we can assume that
476 an attached list of DECL nodes for function formal arguments is present. */
479 gen_decl (decl, is_func_definition, style)
481 int is_func_definition;
486 if (DECL_NAME (decl))
487 ret_val = IDENTIFIER_POINTER (DECL_NAME (decl));
491 /* If we are just generating a list of names of formal parameters, we can
492 simply return the formal parameter name (with no typing information
493 attached to it) now. */
495 if (style == k_and_r_names)
498 /* Note that for the declaration of some entity (either a function or a
499 data object, like for instance a parameter) if the entity itself was
500 declared as either const or volatile, then const and volatile properties
501 are associated with just the declaration of the entity, and *not* with
502 the `type' of the entity. Thus, for such declared entities, we have to
503 generate the qualifiers here. */
505 if (TREE_THIS_VOLATILE (decl))
506 ret_val = concat ("volatile ", ret_val, NULL);
507 if (TREE_READONLY (decl))
508 ret_val = concat ("const ", ret_val, NULL);
512 /* For FUNCTION_DECL nodes, there are two possible cases here. First, if
513 this FUNCTION_DECL node was generated from a function "definition", then
514 we will have a list of DECL_NODE's, one for each of the function's formal
515 parameters. In this case, we can print out not only the types of each
516 formal, but also each formal's name. In the second case, this
517 FUNCTION_DECL node came from an actual function declaration (and *not*
518 a definition). In this case, we do nothing here because the formal
519 argument type-list will be output later, when the "type" of the function
520 is added to the string we are building. Note that the ANSI-style formal
521 parameter list is considered to be a (suffix) part of the "type" of the
524 if (TREE_CODE (decl) == FUNCTION_DECL && is_func_definition)
526 ret_val = concat (ret_val, gen_formal_list_for_func_def (decl, ansi),
529 /* Since we have already added in the formals list stuff, here we don't
530 add the whole "type" of the function we are considering (which
531 would include its parameter-list info), rather, we only add in
532 the "type" of the "type" of the function, which is really just
533 the return-type of the function (and does not include the parameter
536 ret_val = gen_type (ret_val, TREE_TYPE (TREE_TYPE (decl)), style);
539 ret_val = gen_type (ret_val, TREE_TYPE (decl), style);
541 ret_val = affix_data_type (ret_val);
543 if (TREE_CODE (decl) != FUNCTION_DECL && DECL_REGISTER (decl))
544 ret_val = concat ("register ", ret_val, NULL);
545 if (TREE_PUBLIC (decl))
546 ret_val = concat ("extern ", ret_val, NULL);
547 if (TREE_CODE (decl) == FUNCTION_DECL && !TREE_PUBLIC (decl))
548 ret_val = concat ("static ", ret_val, NULL);
553 extern FILE *aux_info_file;
555 /* Generate and write a new line of info to the aux-info (.X) file. This
556 routine is called once for each function declaration, and once for each
557 function definition (even the implicit ones). */
560 gen_aux_info_record (fndecl, is_definition, is_implicit, is_prototyped)
566 if (flag_gen_aux_info)
568 static int compiled_from_record = 0;
570 /* Each output .X file must have a header line. Write one now if we
571 have not yet done so. */
573 if (! compiled_from_record++)
575 /* The first line tells which directory file names are relative to.
576 Currently, -aux-info works only for files in the working
577 directory, so just use a `.' as a placeholder for now. */
578 fprintf (aux_info_file, "/* compiled from: . */\n");
581 /* Write the actual line of auxiliary info. */
583 fprintf (aux_info_file, "/* %s:%d:%c%c */ %s;",
584 DECL_SOURCE_FILE (fndecl),
585 DECL_SOURCE_LINE (fndecl),
586 (is_implicit) ? 'I' : (is_prototyped) ? 'N' : 'O',
587 (is_definition) ? 'F' : 'C',
588 gen_decl (fndecl, is_definition, ansi));
590 /* If this is an explicit function declaration, we need to also write
591 out an old-style (i.e. K&R) function header, just in case the user
592 wants to run unprotoize. */
596 fprintf (aux_info_file, " /*%s %s*/",
597 gen_formal_list_for_func_def (fndecl, k_and_r_names),
598 gen_formal_list_for_func_def (fndecl, k_and_r_decls));
601 fprintf (aux_info_file, "\n");