|
0
|
1 /* Functions dealing with attribute handling, used by most front ends.
|
|
|
2 Copyright (C) 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001,
|
|
|
3 2002, 2003, 2004, 2005, 2007, 2008 Free Software Foundation, Inc.
|
|
|
4
|
|
|
5 This file is part of GCC.
|
|
|
6
|
|
|
7 GCC is free software; you can redistribute it and/or modify it under
|
|
|
8 the terms of the GNU General Public License as published by the Free
|
|
|
9 Software Foundation; either version 3, or (at your option) any later
|
|
|
10 version.
|
|
|
11
|
|
|
12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
|
|
|
13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
|
|
|
14 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
|
|
|
15 for more details.
|
|
|
16
|
|
|
17 You should have received a copy of the GNU General Public License
|
|
|
18 along with GCC; see the file COPYING3. If not see
|
|
|
19 <http://www.gnu.org/licenses/>. */
|
|
|
20
|
|
|
21 #include "config.h"
|
|
|
22 #include "system.h"
|
|
|
23 #include "coretypes.h"
|
|
|
24 #include "tm.h"
|
|
|
25 #include "tree.h"
|
|
|
26 #include "flags.h"
|
|
|
27 #include "toplev.h"
|
|
|
28 #include "output.h"
|
|
|
29 #include "rtl.h"
|
|
|
30 #include "ggc.h"
|
|
|
31 #include "tm_p.h"
|
|
|
32 #include "cpplib.h"
|
|
|
33 #include "target.h"
|
|
|
34 #include "langhooks.h"
|
|
|
35 #include "hashtab.h"
|
|
|
36 #include "c-common.h"
|
|
|
37
|
|
|
38 static void init_attributes (void);
|
|
|
39
|
|
|
40 /* Table of the tables of attributes (common, language, format, machine)
|
|
|
41 searched. */
|
|
|
42 static const struct attribute_spec *attribute_tables[4];
|
|
|
43
|
|
|
44 /* Hashtable mapping names (represented as substrings) to attribute specs. */
|
|
|
45 static htab_t attribute_hash;
|
|
|
46
|
|
|
47 /* Substring representation. */
|
|
|
48
|
|
|
49 struct substring
|
|
|
50 {
|
|
|
51 const char *str;
|
|
|
52 int length;
|
|
|
53 };
|
|
|
54
|
|
|
55 static bool attributes_initialized = false;
|
|
|
56
|
|
|
57 /* Default empty table of attributes. */
|
|
|
58
|
|
|
59 static const struct attribute_spec empty_attribute_table[] =
|
|
|
60 {
|
|
|
61 { NULL, 0, 0, false, false, false, NULL }
|
|
|
62 };
|
|
|
63
|
|
|
64 /* Return base name of the attribute. Ie '__attr__' is turned into 'attr'.
|
|
|
65 To avoid need for copying, we simply return length of the string. */
|
|
|
66
|
|
|
67 static void
|
|
|
68 extract_attribute_substring (struct substring *str)
|
|
|
69 {
|
|
|
70 if (str->length > 4 && str->str[0] == '_' && str->str[1] == '_'
|
|
|
71 && str->str[str->length - 1] == '_' && str->str[str->length - 2] == '_')
|
|
|
72 {
|
|
|
73 str->length -= 4;
|
|
|
74 str->str += 2;
|
|
|
75 }
|
|
|
76 }
|
|
|
77
|
|
|
78 /* Simple hash function to avoid need to scan whole string. */
|
|
|
79
|
|
|
80 static inline hashval_t
|
|
|
81 substring_hash (const char *str, int l)
|
|
|
82 {
|
|
|
83 return str[0] + str[l - 1] * 256 + l * 65536;
|
|
|
84 }
|
|
|
85
|
|
|
86 /* Used for attribute_hash. */
|
|
|
87
|
|
|
88 static hashval_t
|
|
|
89 hash_attr (const void *p)
|
|
|
90 {
|
|
|
91 const struct attribute_spec *const spec = (const struct attribute_spec *) p;
|
|
|
92 const int l = strlen (spec->name);
|
|
|
93
|
|
|
94 return substring_hash (spec->name, l);
|
|
|
95 }
|
|
|
96
|
|
|
97 /* Used for attribute_hash. */
|
|
|
98
|
|
|
99 static int
|
|
|
100 eq_attr (const void *p, const void *q)
|
|
|
101 {
|
|
|
102 const struct attribute_spec *const spec = (const struct attribute_spec *) p;
|
|
|
103 const struct substring *const str = (const struct substring *) q;
|
|
|
104
|
|
|
105 return (!strncmp (spec->name, str->str, str->length) && !spec->name[str->length]);
|
|
|
106 }
|
|
|
107
|
|
|
108 /* Initialize attribute tables, and make some sanity checks
|
|
|
109 if --enable-checking. */
|
|
|
110
|
|
|
111 static void
|
|
|
112 init_attributes (void)
|
|
|
113 {
|
|
|
114 size_t i;
|
|
|
115 int k;
|
|
|
116
|
|
|
117 attribute_tables[0] = lang_hooks.common_attribute_table;
|
|
|
118 attribute_tables[1] = lang_hooks.attribute_table;
|
|
|
119 attribute_tables[2] = lang_hooks.format_attribute_table;
|
|
|
120 attribute_tables[3] = targetm.attribute_table;
|
|
|
121
|
|
|
122 /* Translate NULL pointers to pointers to the empty table. */
|
|
|
123 for (i = 0; i < ARRAY_SIZE (attribute_tables); i++)
|
|
|
124 if (attribute_tables[i] == NULL)
|
|
|
125 attribute_tables[i] = empty_attribute_table;
|
|
|
126
|
|
|
127 #ifdef ENABLE_CHECKING
|
|
|
128 /* Make some sanity checks on the attribute tables. */
|
|
|
129 for (i = 0; i < ARRAY_SIZE (attribute_tables); i++)
|
|
|
130 {
|
|
|
131 int j;
|
|
|
132
|
|
|
133 for (j = 0; attribute_tables[i][j].name != NULL; j++)
|
|
|
134 {
|
|
|
135 /* The name must not begin and end with __. */
|
|
|
136 const char *name = attribute_tables[i][j].name;
|
|
|
137 int len = strlen (name);
|
|
|
138
|
|
|
139 gcc_assert (!(name[0] == '_' && name[1] == '_'
|
|
|
140 && name[len - 1] == '_' && name[len - 2] == '_'));
|
|
|
141
|
|
|
142 /* The minimum and maximum lengths must be consistent. */
|
|
|
143 gcc_assert (attribute_tables[i][j].min_length >= 0);
|
|
|
144
|
|
|
145 gcc_assert (attribute_tables[i][j].max_length == -1
|
|
|
146 || (attribute_tables[i][j].max_length
|
|
|
147 >= attribute_tables[i][j].min_length));
|
|
|
148
|
|
|
149 /* An attribute cannot require both a DECL and a TYPE. */
|
|
|
150 gcc_assert (!attribute_tables[i][j].decl_required
|
|
|
151 || !attribute_tables[i][j].type_required);
|
|
|
152
|
|
|
153 /* If an attribute requires a function type, in particular
|
|
|
154 it requires a type. */
|
|
|
155 gcc_assert (!attribute_tables[i][j].function_type_required
|
|
|
156 || attribute_tables[i][j].type_required);
|
|
|
157 }
|
|
|
158 }
|
|
|
159
|
|
|
160 /* Check that each name occurs just once in each table. */
|
|
|
161 for (i = 0; i < ARRAY_SIZE (attribute_tables); i++)
|
|
|
162 {
|
|
|
163 int j, k;
|
|
|
164 for (j = 0; attribute_tables[i][j].name != NULL; j++)
|
|
|
165 for (k = j + 1; attribute_tables[i][k].name != NULL; k++)
|
|
|
166 gcc_assert (strcmp (attribute_tables[i][j].name,
|
|
|
167 attribute_tables[i][k].name));
|
|
|
168 }
|
|
|
169 /* Check that no name occurs in more than one table. */
|
|
|
170 for (i = 0; i < ARRAY_SIZE (attribute_tables); i++)
|
|
|
171 {
|
|
|
172 size_t j, k, l;
|
|
|
173
|
|
|
174 for (j = i + 1; j < ARRAY_SIZE (attribute_tables); j++)
|
|
|
175 for (k = 0; attribute_tables[i][k].name != NULL; k++)
|
|
|
176 for (l = 0; attribute_tables[j][l].name != NULL; l++)
|
|
|
177 gcc_assert (strcmp (attribute_tables[i][k].name,
|
|
|
178 attribute_tables[j][l].name));
|
|
|
179 }
|
|
|
180 #endif
|
|
|
181
|
|
|
182 attribute_hash = htab_create (200, hash_attr, eq_attr, NULL);
|
|
|
183 for (i = 0; i < ARRAY_SIZE (attribute_tables); i++)
|
|
|
184 for (k = 0; attribute_tables[i][k].name != NULL; k++)
|
|
|
185 {
|
|
|
186 struct substring str;
|
|
|
187 const void **slot;
|
|
|
188
|
|
|
189 str.str = attribute_tables[i][k].name;
|
|
|
190 str.length = strlen (attribute_tables[i][k].name);
|
|
|
191 slot = (const void **)htab_find_slot_with_hash (attribute_hash, &str,
|
|
|
192 substring_hash (str.str, str.length),
|
|
|
193 INSERT);
|
|
|
194 gcc_assert (!*slot);
|
|
|
195 *slot = &attribute_tables[i][k];
|
|
|
196 }
|
|
|
197 attributes_initialized = true;
|
|
|
198 }
|
|
|
199
|
|
|
200 /* Return the spec for the attribute named NAME. */
|
|
|
201
|
|
|
202 const struct attribute_spec *
|
|
|
203 lookup_attribute_spec (tree name)
|
|
|
204 {
|
|
|
205 struct substring attr;
|
|
|
206
|
|
|
207 attr.str = IDENTIFIER_POINTER (name);
|
|
|
208 attr.length = IDENTIFIER_LENGTH (name);
|
|
|
209 extract_attribute_substring (&attr);
|
|
|
210 return (const struct attribute_spec *)
|
|
|
211 htab_find_with_hash (attribute_hash, &attr,
|
|
|
212 substring_hash (attr.str, attr.length));
|
|
|
213 }
|
|
|
214
|
|
|
215 /* Process the attributes listed in ATTRIBUTES and install them in *NODE,
|
|
|
216 which is either a DECL (including a TYPE_DECL) or a TYPE. If a DECL,
|
|
|
217 it should be modified in place; if a TYPE, a copy should be created
|
|
|
218 unless ATTR_FLAG_TYPE_IN_PLACE is set in FLAGS. FLAGS gives further
|
|
|
219 information, in the form of a bitwise OR of flags in enum attribute_flags
|
|
|
220 from tree.h. Depending on these flags, some attributes may be
|
|
|
221 returned to be applied at a later stage (for example, to apply
|
|
|
222 a decl attribute to the declaration rather than to its type). */
|
|
|
223
|
|
|
224 tree
|
|
|
225 decl_attributes (tree *node, tree attributes, int flags)
|
|
|
226 {
|
|
|
227 tree a;
|
|
|
228 tree returned_attrs = NULL_TREE;
|
|
|
229
|
|
|
230 if (TREE_TYPE (*node) == error_mark_node)
|
|
|
231 return NULL_TREE;
|
|
|
232
|
|
|
233 if (!attributes_initialized)
|
|
|
234 init_attributes ();
|
|
|
235
|
|
|
236 /* If this is a function and the user used #pragma GCC optimize, add the
|
|
|
237 options to the attribute((optimize(...))) list. */
|
|
|
238 if (TREE_CODE (*node) == FUNCTION_DECL && current_optimize_pragma)
|
|
|
239 {
|
|
|
240 tree cur_attr = lookup_attribute ("optimize", attributes);
|
|
|
241 tree opts = copy_list (current_optimize_pragma);
|
|
|
242
|
|
|
243 if (! cur_attr)
|
|
|
244 attributes
|
|
|
245 = tree_cons (get_identifier ("optimize"), opts, attributes);
|
|
|
246 else
|
|
|
247 TREE_VALUE (cur_attr) = chainon (opts, TREE_VALUE (cur_attr));
|
|
|
248 }
|
|
|
249
|
|
|
250 if (TREE_CODE (*node) == FUNCTION_DECL
|
|
|
251 && optimization_current_node != optimization_default_node
|
|
|
252 && !DECL_FUNCTION_SPECIFIC_OPTIMIZATION (*node))
|
|
|
253 DECL_FUNCTION_SPECIFIC_OPTIMIZATION (*node) = optimization_current_node;
|
|
|
254
|
|
|
255 /* If this is a function and the user used #pragma GCC target, add the
|
|
|
256 options to the attribute((target(...))) list. */
|
|
|
257 if (TREE_CODE (*node) == FUNCTION_DECL
|
|
|
258 && current_target_pragma
|
|
|
259 && targetm.target_option.valid_attribute_p (*node, NULL_TREE,
|
|
|
260 current_target_pragma, 0))
|
|
|
261 {
|
|
|
262 tree cur_attr = lookup_attribute ("target", attributes);
|
|
|
263 tree opts = copy_list (current_target_pragma);
|
|
|
264
|
|
|
265 if (! cur_attr)
|
|
|
266 attributes = tree_cons (get_identifier ("target"), opts, attributes);
|
|
|
267 else
|
|
|
268 TREE_VALUE (cur_attr) = chainon (opts, TREE_VALUE (cur_attr));
|
|
|
269 }
|
|
|
270
|
|
|
271 targetm.insert_attributes (*node, &attributes);
|
|
|
272
|
|
|
273 for (a = attributes; a; a = TREE_CHAIN (a))
|
|
|
274 {
|
|
|
275 tree name = TREE_PURPOSE (a);
|
|
|
276 tree args = TREE_VALUE (a);
|
|
|
277 tree *anode = node;
|
|
|
278 const struct attribute_spec *spec = lookup_attribute_spec (name);
|
|
|
279 bool no_add_attrs = 0;
|
|
|
280 tree fn_ptr_tmp = NULL_TREE;
|
|
|
281
|
|
|
282 if (spec == NULL)
|
|
|
283 {
|
|
|
284 warning (OPT_Wattributes, "%qs attribute directive ignored",
|
|
|
285 IDENTIFIER_POINTER (name));
|
|
|
286 continue;
|
|
|
287 }
|
|
|
288 else if (list_length (args) < spec->min_length
|
|
|
289 || (spec->max_length >= 0
|
|
|
290 && list_length (args) > spec->max_length))
|
|
|
291 {
|
|
|
292 error ("wrong number of arguments specified for %qs attribute",
|
|
|
293 IDENTIFIER_POINTER (name));
|
|
|
294 continue;
|
|
|
295 }
|
|
|
296 gcc_assert (is_attribute_p (spec->name, name));
|
|
|
297
|
|
|
298 if (spec->decl_required && !DECL_P (*anode))
|
|
|
299 {
|
|
|
300 if (flags & ((int) ATTR_FLAG_DECL_NEXT
|
|
|
301 | (int) ATTR_FLAG_FUNCTION_NEXT
|
|
|
302 | (int) ATTR_FLAG_ARRAY_NEXT))
|
|
|
303 {
|
|
|
304 /* Pass on this attribute to be tried again. */
|
|
|
305 returned_attrs = tree_cons (name, args, returned_attrs);
|
|
|
306 continue;
|
|
|
307 }
|
|
|
308 else
|
|
|
309 {
|
|
|
310 warning (OPT_Wattributes, "%qs attribute does not apply to types",
|
|
|
311 IDENTIFIER_POINTER (name));
|
|
|
312 continue;
|
|
|
313 }
|
|
|
314 }
|
|
|
315
|
|
|
316 /* If we require a type, but were passed a decl, set up to make a
|
|
|
317 new type and update the one in the decl. ATTR_FLAG_TYPE_IN_PLACE
|
|
|
318 would have applied if we'd been passed a type, but we cannot modify
|
|
|
319 the decl's type in place here. */
|
|
|
320 if (spec->type_required && DECL_P (*anode))
|
|
|
321 {
|
|
|
322 anode = &TREE_TYPE (*anode);
|
|
|
323 /* Allow ATTR_FLAG_TYPE_IN_PLACE for the type's naming decl. */
|
|
|
324 if (!(TREE_CODE (*anode) == TYPE_DECL
|
|
|
325 && *anode == TYPE_NAME (TYPE_MAIN_VARIANT
|
|
|
326 (TREE_TYPE (*anode)))))
|
|
|
327 flags &= ~(int) ATTR_FLAG_TYPE_IN_PLACE;
|
|
|
328 }
|
|
|
329
|
|
|
330 if (spec->function_type_required && TREE_CODE (*anode) != FUNCTION_TYPE
|
|
|
331 && TREE_CODE (*anode) != METHOD_TYPE)
|
|
|
332 {
|
|
|
333 if (TREE_CODE (*anode) == POINTER_TYPE
|
|
|
334 && (TREE_CODE (TREE_TYPE (*anode)) == FUNCTION_TYPE
|
|
|
335 || TREE_CODE (TREE_TYPE (*anode)) == METHOD_TYPE))
|
|
|
336 {
|
|
|
337 /* OK, this is a bit convoluted. We can't just make a copy
|
|
|
338 of the pointer type and modify its TREE_TYPE, because if
|
|
|
339 we change the attributes of the target type the pointer
|
|
|
340 type needs to have a different TYPE_MAIN_VARIANT. So we
|
|
|
341 pull out the target type now, frob it as appropriate, and
|
|
|
342 rebuild the pointer type later.
|
|
|
343
|
|
|
344 This would all be simpler if attributes were part of the
|
|
|
345 declarator, grumble grumble. */
|
|
|
346 fn_ptr_tmp = TREE_TYPE (*anode);
|
|
|
347 anode = &fn_ptr_tmp;
|
|
|
348 flags &= ~(int) ATTR_FLAG_TYPE_IN_PLACE;
|
|
|
349 }
|
|
|
350 else if (flags & (int) ATTR_FLAG_FUNCTION_NEXT)
|
|
|
351 {
|
|
|
352 /* Pass on this attribute to be tried again. */
|
|
|
353 returned_attrs = tree_cons (name, args, returned_attrs);
|
|
|
354 continue;
|
|
|
355 }
|
|
|
356
|
|
|
357 if (TREE_CODE (*anode) != FUNCTION_TYPE
|
|
|
358 && TREE_CODE (*anode) != METHOD_TYPE)
|
|
|
359 {
|
|
|
360 warning (OPT_Wattributes,
|
|
|
361 "%qs attribute only applies to function types",
|
|
|
362 IDENTIFIER_POINTER (name));
|
|
|
363 continue;
|
|
|
364 }
|
|
|
365 }
|
|
|
366
|
|
|
367 if (TYPE_P (*anode)
|
|
|
368 && (flags & (int) ATTR_FLAG_TYPE_IN_PLACE)
|
|
|
369 && TYPE_SIZE (*anode) != NULL_TREE)
|
|
|
370 {
|
|
|
371 warning (OPT_Wattributes, "type attributes ignored after type is already defined");
|
|
|
372 continue;
|
|
|
373 }
|
|
|
374
|
|
|
375 if (spec->handler != NULL)
|
|
|
376 returned_attrs = chainon ((*spec->handler) (anode, name, args,
|
|
|
377 flags, &no_add_attrs),
|
|
|
378 returned_attrs);
|
|
|
379
|
|
|
380 /* Layout the decl in case anything changed. */
|
|
|
381 if (spec->type_required && DECL_P (*node)
|
|
|
382 && (TREE_CODE (*node) == VAR_DECL
|
|
|
383 || TREE_CODE (*node) == PARM_DECL
|
|
|
384 || TREE_CODE (*node) == RESULT_DECL))
|
|
|
385 relayout_decl (*node);
|
|
|
386
|
|
|
387 if (!no_add_attrs)
|
|
|
388 {
|
|
|
389 tree old_attrs;
|
|
|
390 tree a;
|
|
|
391
|
|
|
392 if (DECL_P (*anode))
|
|
|
393 old_attrs = DECL_ATTRIBUTES (*anode);
|
|
|
394 else
|
|
|
395 old_attrs = TYPE_ATTRIBUTES (*anode);
|
|
|
396
|
|
|
397 for (a = lookup_attribute (spec->name, old_attrs);
|
|
|
398 a != NULL_TREE;
|
|
|
399 a = lookup_attribute (spec->name, TREE_CHAIN (a)))
|
|
|
400 {
|
|
|
401 if (simple_cst_equal (TREE_VALUE (a), args) == 1)
|
|
|
402 break;
|
|
|
403 }
|
|
|
404
|
|
|
405 if (a == NULL_TREE)
|
|
|
406 {
|
|
|
407 /* This attribute isn't already in the list. */
|
|
|
408 if (DECL_P (*anode))
|
|
|
409 DECL_ATTRIBUTES (*anode) = tree_cons (name, args, old_attrs);
|
|
|
410 else if (flags & (int) ATTR_FLAG_TYPE_IN_PLACE)
|
|
|
411 {
|
|
|
412 TYPE_ATTRIBUTES (*anode) = tree_cons (name, args, old_attrs);
|
|
|
413 /* If this is the main variant, also push the attributes
|
|
|
414 out to the other variants. */
|
|
|
415 if (*anode == TYPE_MAIN_VARIANT (*anode))
|
|
|
416 {
|
|
|
417 tree variant;
|
|
|
418 for (variant = *anode; variant;
|
|
|
419 variant = TYPE_NEXT_VARIANT (variant))
|
|
|
420 {
|
|
|
421 if (TYPE_ATTRIBUTES (variant) == old_attrs)
|
|
|
422 TYPE_ATTRIBUTES (variant)
|
|
|
423 = TYPE_ATTRIBUTES (*anode);
|
|
|
424 else if (!lookup_attribute
|
|
|
425 (spec->name, TYPE_ATTRIBUTES (variant)))
|
|
|
426 TYPE_ATTRIBUTES (variant) = tree_cons
|
|
|
427 (name, args, TYPE_ATTRIBUTES (variant));
|
|
|
428 }
|
|
|
429 }
|
|
|
430 }
|
|
|
431 else
|
|
|
432 *anode = build_type_attribute_variant (*anode,
|
|
|
433 tree_cons (name, args,
|
|
|
434 old_attrs));
|
|
|
435 }
|
|
|
436 }
|
|
|
437
|
|
|
438 if (fn_ptr_tmp)
|
|
|
439 {
|
|
|
440 /* Rebuild the function pointer type and put it in the
|
|
|
441 appropriate place. */
|
|
|
442 fn_ptr_tmp = build_pointer_type (fn_ptr_tmp);
|
|
|
443 if (DECL_P (*node))
|
|
|
444 TREE_TYPE (*node) = fn_ptr_tmp;
|
|
|
445 else
|
|
|
446 {
|
|
|
447 gcc_assert (TREE_CODE (*node) == POINTER_TYPE);
|
|
|
448 *node = fn_ptr_tmp;
|
|
|
449 }
|
|
|
450 }
|
|
|
451 }
|
|
|
452
|
|
|
453 return returned_attrs;
|
|
|
454 }
|
