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400fbf9f JW |
1 | /* Build expressions with type checking for C compiler. |
2 | Copyright (C) 1987, 1988, 1989, 1992 Free Software Foundation, Inc. | |
3 | ||
4 | This file is part of GNU CC. | |
5 | ||
6 | GNU CC is free software; you can redistribute it and/or modify | |
7 | it under the terms of the GNU General Public License as published by | |
8 | the Free Software Foundation; either version 2, or (at your option) | |
9 | any later version. | |
10 | ||
11 | GNU CC is distributed in the hope that it will be useful, | |
12 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
13 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
14 | GNU General Public License for more details. | |
15 | ||
16 | You should have received a copy of the GNU General Public License | |
17 | along with GNU CC; see the file COPYING. If not, write to | |
18 | the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */ | |
19 | ||
20 | ||
21 | /* This file is part of the C front end. | |
22 | It contains routines to build C expressions given their operands, | |
23 | including computing the types of the result, C-specific error checks, | |
24 | and some optimization. | |
25 | ||
26 | There are also routines to build RETURN_STMT nodes and CASE_STMT nodes, | |
27 | and to process initializations in declarations (since they work | |
28 | like a strange sort of assignment). */ | |
29 | ||
30 | #include "config.h" | |
31 | #include <stdio.h> | |
32 | #include "tree.h" | |
33 | #include "c-tree.h" | |
34 | #include "flags.h" | |
35 | ||
3845b542 MS |
36 | extern char *index (); |
37 | extern char *rindex (); | |
38 | ||
400fbf9f JW |
39 | int mark_addressable (); |
40 | static tree convert_for_assignment (); | |
41 | static void warn_for_assignment (); | |
42 | static int function_types_compatible_p (); | |
43 | static int type_lists_compatible_p (); | |
805f961c | 44 | int self_promoting_args_p (); |
400fbf9f JW |
45 | static int self_promoting_type_p (); |
46 | static int comp_target_types (); | |
47 | static tree pointer_int_sum (); | |
48 | static tree pointer_diff (); | |
49 | static tree convert_sequence (); | |
50 | static tree unary_complex_lvalue (); | |
51 | static tree process_init_constructor (); | |
52 | static tree convert_arguments (); | |
d45cf215 | 53 | static char *get_spelling (); |
400fbf9f JW |
54 | tree digest_init (); |
55 | static void pedantic_lvalue_warning (); | |
56 | tree truthvalue_conversion (); | |
57 | void incomplete_type_error (); | |
58 | void readonly_warning (); | |
59 | \f | |
60 | /* Do `exp = require_complete_type (exp);' to make sure exp | |
61 | does not have an incomplete type. (That includes void types.) */ | |
62 | ||
63 | tree | |
64 | require_complete_type (value) | |
65 | tree value; | |
66 | { | |
67 | tree type = TREE_TYPE (value); | |
68 | ||
69 | /* First, detect a valid value with a complete type. */ | |
70 | if (TYPE_SIZE (type) != 0 | |
71 | && type != void_type_node) | |
72 | return value; | |
73 | ||
74 | incomplete_type_error (value, type); | |
75 | return error_mark_node; | |
76 | } | |
77 | ||
78 | /* Print an error message for invalid use of an incomplete type. | |
79 | VALUE is the expression that was used (or 0 if that isn't known) | |
80 | and TYPE is the type that was invalid. */ | |
81 | ||
82 | void | |
83 | incomplete_type_error (value, type) | |
84 | tree value; | |
85 | tree type; | |
86 | { | |
87 | char *errmsg; | |
88 | ||
89 | /* Avoid duplicate error message. */ | |
90 | if (TREE_CODE (type) == ERROR_MARK) | |
91 | return; | |
92 | ||
93 | if (value != 0 && (TREE_CODE (value) == VAR_DECL | |
94 | || TREE_CODE (value) == PARM_DECL)) | |
95 | error ("`%s' has an incomplete type", | |
96 | IDENTIFIER_POINTER (DECL_NAME (value))); | |
97 | else | |
98 | { | |
99 | retry: | |
100 | /* We must print an error message. Be clever about what it says. */ | |
101 | ||
102 | switch (TREE_CODE (type)) | |
103 | { | |
104 | case RECORD_TYPE: | |
105 | errmsg = "invalid use of undefined type `struct %s'"; | |
106 | break; | |
107 | ||
108 | case UNION_TYPE: | |
109 | errmsg = "invalid use of undefined type `union %s'"; | |
110 | break; | |
111 | ||
112 | case ENUMERAL_TYPE: | |
113 | errmsg = "invalid use of undefined type `enum %s'"; | |
114 | break; | |
115 | ||
116 | case VOID_TYPE: | |
117 | error ("invalid use of void expression"); | |
118 | return; | |
119 | ||
120 | case ARRAY_TYPE: | |
121 | if (TYPE_DOMAIN (type)) | |
122 | { | |
123 | type = TREE_TYPE (type); | |
124 | goto retry; | |
125 | } | |
126 | error ("invalid use of array with unspecified bounds"); | |
127 | return; | |
128 | ||
129 | default: | |
130 | abort (); | |
131 | } | |
132 | ||
133 | if (TREE_CODE (TYPE_NAME (type)) == IDENTIFIER_NODE) | |
134 | error (errmsg, IDENTIFIER_POINTER (TYPE_NAME (type))); | |
135 | else | |
136 | /* If this type has a typedef-name, the TYPE_NAME is a TYPE_DECL. */ | |
137 | error ("invalid use of incomplete typedef `%s'", | |
138 | IDENTIFIER_POINTER (DECL_NAME (TYPE_NAME (type)))); | |
139 | } | |
140 | } | |
141 | ||
142 | /* Return a variant of TYPE which has all the type qualifiers of LIKE | |
143 | as well as those of TYPE. */ | |
144 | ||
145 | static tree | |
146 | qualify_type (type, like) | |
147 | tree type, like; | |
148 | { | |
149 | int constflag = TYPE_READONLY (type) || TYPE_READONLY (like); | |
150 | int volflag = TYPE_VOLATILE (type) || TYPE_VOLATILE (like); | |
151 | return c_build_type_variant (type, constflag, volflag); | |
152 | } | |
153 | \f | |
154 | /* Return the common type of two types. | |
155 | We assume that comptypes has already been done and returned 1; | |
156 | if that isn't so, this may crash. | |
157 | ||
158 | This is the type for the result of most arithmetic operations | |
159 | if the operands have the given two types. | |
160 | ||
161 | We do not deal with enumeral types here because they have already been | |
162 | converted to integer types. */ | |
163 | ||
164 | tree | |
165 | common_type (t1, t2) | |
166 | tree t1, t2; | |
167 | { | |
168 | register enum tree_code code1; | |
169 | register enum tree_code code2; | |
170 | ||
171 | /* Save time if the two types are the same. */ | |
172 | ||
173 | if (t1 == t2) return t1; | |
174 | ||
175 | /* If one type is nonsense, use the other. */ | |
176 | if (t1 == error_mark_node) | |
177 | return t2; | |
178 | if (t2 == error_mark_node) | |
179 | return t1; | |
180 | ||
181 | /* Treat an enum type as the unsigned integer type of the same width. */ | |
182 | ||
183 | if (TREE_CODE (t1) == ENUMERAL_TYPE) | |
184 | t1 = type_for_size (TYPE_PRECISION (t1), 1); | |
185 | if (TREE_CODE (t2) == ENUMERAL_TYPE) | |
186 | t2 = type_for_size (TYPE_PRECISION (t2), 1); | |
187 | ||
188 | code1 = TREE_CODE (t1); | |
189 | code2 = TREE_CODE (t2); | |
190 | ||
191 | switch (code1) | |
192 | { | |
193 | case INTEGER_TYPE: | |
194 | case REAL_TYPE: | |
195 | /* If only one is real, use it as the result. */ | |
196 | ||
197 | if (code1 == REAL_TYPE && code2 != REAL_TYPE) | |
198 | return t1; | |
199 | ||
200 | if (code2 == REAL_TYPE && code1 != REAL_TYPE) | |
201 | return t2; | |
202 | ||
203 | /* Both real or both integers; use the one with greater precision. */ | |
204 | ||
205 | if (TYPE_PRECISION (t1) > TYPE_PRECISION (t2)) | |
206 | return t1; | |
207 | else if (TYPE_PRECISION (t2) > TYPE_PRECISION (t1)) | |
208 | return t2; | |
209 | ||
210 | /* Same precision. Prefer longs to ints even when same size. */ | |
211 | ||
212 | if (t1 == long_unsigned_type_node | |
213 | || t2 == long_unsigned_type_node) | |
214 | return long_unsigned_type_node; | |
215 | ||
216 | if (t1 == long_integer_type_node | |
217 | || t2 == long_integer_type_node) | |
218 | { | |
219 | /* But preserve unsignedness from the other type, | |
220 | since long cannot hold all the values of an unsigned int. */ | |
221 | if (TREE_UNSIGNED (t1) || TREE_UNSIGNED (t2)) | |
222 | return long_unsigned_type_node; | |
223 | return long_integer_type_node; | |
224 | } | |
225 | ||
226 | /* Otherwise prefer the unsigned one. */ | |
227 | ||
228 | if (TREE_UNSIGNED (t1)) | |
229 | return t1; | |
230 | else return t2; | |
231 | ||
232 | case POINTER_TYPE: | |
233 | #if 0 | |
234 | /* For two pointers, do this recursively on the target type, | |
235 | and combine the qualifiers of the two types' targets. */ | |
236 | { | |
237 | tree target = common_type (TYPE_MAIN_VARIANT (TREE_TYPE (t1)), | |
238 | TYPE_MAIN_VARIANT (TREE_TYPE (t2))); | |
239 | int constp | |
240 | = TYPE_READONLY (TREE_TYPE (t1)) || TYPE_READONLY (TREE_TYPE (t2)); | |
241 | int volatilep | |
242 | = TYPE_VOLATILE (TREE_TYPE (t1)) || TYPE_VOLATILE (TREE_TYPE (t2)); | |
243 | return build_pointer_type (c_build_type_variant (target, constp, volatilep)); | |
244 | } | |
245 | #endif | |
246 | return build_pointer_type (common_type (TREE_TYPE (t1), TREE_TYPE (t2))); | |
247 | ||
248 | case ARRAY_TYPE: | |
249 | { | |
250 | tree elt = common_type (TREE_TYPE (t1), TREE_TYPE (t2)); | |
251 | /* Save space: see if the result is identical to one of the args. */ | |
252 | if (elt == TREE_TYPE (t1) && TYPE_DOMAIN (t1)) | |
253 | return t1; | |
254 | if (elt == TREE_TYPE (t2) && TYPE_DOMAIN (t2)) | |
255 | return t2; | |
256 | /* Merge the element types, and have a size if either arg has one. */ | |
257 | return build_array_type (elt, TYPE_DOMAIN (TYPE_DOMAIN (t1) ? t1 : t2)); | |
258 | } | |
259 | ||
260 | case FUNCTION_TYPE: | |
261 | /* Function types: prefer the one that specified arg types. | |
262 | If both do, merge the arg types. Also merge the return types. */ | |
263 | { | |
264 | tree valtype = common_type (TREE_TYPE (t1), TREE_TYPE (t2)); | |
265 | tree p1 = TYPE_ARG_TYPES (t1); | |
266 | tree p2 = TYPE_ARG_TYPES (t2); | |
267 | int len; | |
268 | tree newargs, n; | |
269 | int i; | |
270 | ||
271 | /* Save space: see if the result is identical to one of the args. */ | |
272 | if (valtype == TREE_TYPE (t1) && ! TYPE_ARG_TYPES (t2)) | |
273 | return t1; | |
274 | if (valtype == TREE_TYPE (t2) && ! TYPE_ARG_TYPES (t1)) | |
275 | return t2; | |
276 | ||
277 | /* Simple way if one arg fails to specify argument types. */ | |
278 | if (TYPE_ARG_TYPES (t1) == 0) | |
279 | return build_function_type (valtype, TYPE_ARG_TYPES (t2)); | |
280 | if (TYPE_ARG_TYPES (t2) == 0) | |
281 | return build_function_type (valtype, TYPE_ARG_TYPES (t1)); | |
282 | ||
283 | /* If both args specify argument types, we must merge the two | |
284 | lists, argument by argument. */ | |
285 | ||
286 | len = list_length (p1); | |
287 | newargs = 0; | |
288 | ||
289 | for (i = 0; i < len; i++) | |
290 | newargs = tree_cons (0, 0, newargs); | |
291 | ||
292 | n = newargs; | |
293 | ||
294 | for (; p1; | |
295 | p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2), n = TREE_CHAIN (n)) | |
296 | { | |
297 | /* A null type means arg type is not specified. | |
298 | Take whatever the other function type has. */ | |
299 | if (TREE_VALUE (p1) == 0) | |
300 | { | |
301 | TREE_VALUE (n) = TREE_VALUE (p2); | |
302 | goto parm_done; | |
303 | } | |
304 | if (TREE_VALUE (p2) == 0) | |
305 | { | |
306 | TREE_VALUE (n) = TREE_VALUE (p1); | |
307 | goto parm_done; | |
308 | } | |
309 | ||
310 | /* Given wait (union {union wait *u; int *i} *) | |
311 | and wait (union wait *), | |
312 | prefer union wait * as type of parm. */ | |
313 | if (TREE_CODE (TREE_VALUE (p1)) == UNION_TYPE | |
314 | && TREE_VALUE (p1) != TREE_VALUE (p2)) | |
315 | { | |
316 | tree memb; | |
317 | for (memb = TYPE_FIELDS (TREE_VALUE (p1)); | |
318 | memb; memb = TREE_CHAIN (memb)) | |
319 | if (comptypes (TREE_TYPE (memb), TREE_VALUE (p2))) | |
320 | { | |
321 | TREE_VALUE (n) = TREE_VALUE (p2); | |
322 | if (pedantic) | |
323 | pedwarn ("function types not truly compatible in ANSI C"); | |
324 | goto parm_done; | |
325 | } | |
326 | } | |
327 | if (TREE_CODE (TREE_VALUE (p2)) == UNION_TYPE | |
328 | && TREE_VALUE (p2) != TREE_VALUE (p1)) | |
329 | { | |
330 | tree memb; | |
331 | for (memb = TYPE_FIELDS (TREE_VALUE (p2)); | |
332 | memb; memb = TREE_CHAIN (memb)) | |
333 | if (comptypes (TREE_TYPE (memb), TREE_VALUE (p1))) | |
334 | { | |
335 | TREE_VALUE (n) = TREE_VALUE (p1); | |
336 | if (pedantic) | |
337 | pedwarn ("function types not truly compatible in ANSI C"); | |
338 | goto parm_done; | |
339 | } | |
340 | } | |
341 | TREE_VALUE (n) = common_type (TREE_VALUE (p1), TREE_VALUE (p2)); | |
342 | parm_done: ; | |
343 | } | |
344 | ||
345 | return build_function_type (valtype, newargs); | |
346 | } | |
347 | ||
348 | default: | |
349 | return t1; | |
350 | } | |
351 | ||
352 | } | |
353 | \f | |
354 | /* Return 1 if TYPE1 and TYPE2 are compatible types for assignment | |
355 | or various other operations. Return 2 if they are compatible | |
356 | but a warning may be needed if you use them together. */ | |
357 | ||
358 | int | |
359 | comptypes (type1, type2) | |
360 | tree type1, type2; | |
361 | { | |
362 | register tree t1 = type1; | |
363 | register tree t2 = type2; | |
364 | ||
365 | /* Suppress errors caused by previously reported errors. */ | |
366 | ||
367 | if (t1 == t2 || TREE_CODE (t1) == ERROR_MARK || TREE_CODE (t2) == ERROR_MARK) | |
368 | return 1; | |
369 | ||
370 | /* Treat an enum type as the unsigned integer type of the same width. */ | |
371 | ||
372 | if (TREE_CODE (t1) == ENUMERAL_TYPE) | |
373 | t1 = type_for_size (TYPE_PRECISION (t1), 1); | |
374 | if (TREE_CODE (t2) == ENUMERAL_TYPE) | |
375 | t2 = type_for_size (TYPE_PRECISION (t2), 1); | |
376 | ||
377 | if (t1 == t2) | |
378 | return 1; | |
379 | ||
380 | /* Different classes of types can't be compatible. */ | |
381 | ||
382 | if (TREE_CODE (t1) != TREE_CODE (t2)) return 0; | |
383 | ||
384 | /* Qualifiers must match. */ | |
385 | ||
386 | if (TYPE_READONLY (t1) != TYPE_READONLY (t2)) | |
387 | return 0; | |
388 | if (TYPE_VOLATILE (t1) != TYPE_VOLATILE (t2)) | |
389 | return 0; | |
390 | ||
d45cf215 | 391 | /* If generating auxiliary info, allow for two different type nodes which |
400fbf9f JW |
392 | have essentially the same definition. */ |
393 | ||
394 | if (TYPE_MAIN_VARIANT (t1) == TYPE_MAIN_VARIANT (t2)) | |
395 | return 1; | |
396 | ||
397 | switch (TREE_CODE (t1)) | |
398 | { | |
399 | case POINTER_TYPE: | |
400 | return (TREE_TYPE (t1) == TREE_TYPE (t2) | |
401 | ? 1 : comptypes (TREE_TYPE (t1), TREE_TYPE (t2))); | |
402 | ||
403 | case FUNCTION_TYPE: | |
404 | return function_types_compatible_p (t1, t2); | |
405 | ||
406 | case ARRAY_TYPE: | |
407 | { | |
408 | /* 1 if no need for warning yet, 2 if warning cause has been seen. */ | |
409 | int val = 1; | |
410 | tree d1 = TYPE_DOMAIN (t1); | |
411 | tree d2 = TYPE_DOMAIN (t2); | |
412 | ||
413 | /* Target types must match incl. qualifiers. */ | |
414 | if (TREE_TYPE (t1) != TREE_TYPE (t2) | |
415 | && 0 == (val = comptypes (TREE_TYPE (t1), TREE_TYPE (t2)))) | |
416 | return 0; | |
417 | ||
418 | /* Sizes must match unless one is missing or variable. */ | |
419 | if (d1 == 0 || d2 == 0 || d1 == d2 | |
420 | || TREE_CODE (TYPE_MIN_VALUE (d1)) != INTEGER_CST | |
421 | || TREE_CODE (TYPE_MIN_VALUE (d2)) != INTEGER_CST | |
422 | || TREE_CODE (TYPE_MAX_VALUE (d1)) != INTEGER_CST | |
423 | || TREE_CODE (TYPE_MAX_VALUE (d2)) != INTEGER_CST) | |
424 | return val; | |
425 | ||
426 | return (((TREE_INT_CST_LOW (TYPE_MIN_VALUE (d1)) | |
427 | == TREE_INT_CST_LOW (TYPE_MIN_VALUE (d2))) | |
428 | && (TREE_INT_CST_HIGH (TYPE_MIN_VALUE (d1)) | |
429 | == TREE_INT_CST_HIGH (TYPE_MIN_VALUE (d2))) | |
430 | && (TREE_INT_CST_LOW (TYPE_MAX_VALUE (d1)) | |
431 | == TREE_INT_CST_LOW (TYPE_MAX_VALUE (d2))) | |
432 | && (TREE_INT_CST_HIGH (TYPE_MAX_VALUE (d1)) | |
433 | == TREE_INT_CST_HIGH (TYPE_MAX_VALUE (d2)))) | |
434 | ? val : 0); | |
435 | } | |
436 | ||
437 | case RECORD_TYPE: | |
438 | return maybe_objc_comptypes (t1, t2); | |
439 | } | |
440 | return 0; | |
441 | } | |
442 | ||
443 | /* Return 1 if TTL and TTR are pointers to types that are equivalent, | |
444 | ignoring their qualifiers. */ | |
445 | ||
446 | static int | |
447 | comp_target_types (ttl, ttr) | |
448 | tree ttl, ttr; | |
449 | { | |
450 | int val = comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (ttl)), | |
451 | TYPE_MAIN_VARIANT (TREE_TYPE (ttr))); | |
452 | if (val == 2 && pedantic) | |
453 | pedwarn ("types are not quite compatible"); | |
454 | return val; | |
455 | } | |
456 | \f | |
457 | /* Subroutines of `comptypes'. */ | |
458 | ||
459 | /* Return 1 if two function types F1 and F2 are compatible. | |
460 | If either type specifies no argument types, | |
461 | the other must specify a fixed number of self-promoting arg types. | |
462 | Otherwise, if one type specifies only the number of arguments, | |
463 | the other must specify that number of self-promoting arg types. | |
464 | Otherwise, the argument types must match. */ | |
465 | ||
466 | static int | |
467 | function_types_compatible_p (f1, f2) | |
468 | tree f1, f2; | |
469 | { | |
470 | tree args1, args2; | |
471 | /* 1 if no need for warning yet, 2 if warning cause has been seen. */ | |
472 | int val = 1; | |
473 | int val1; | |
474 | ||
475 | if (!(TREE_TYPE (f1) == TREE_TYPE (f2) | |
476 | || (val = comptypes (TREE_TYPE (f1), TREE_TYPE (f2))))) | |
477 | return 0; | |
478 | ||
479 | args1 = TYPE_ARG_TYPES (f1); | |
480 | args2 = TYPE_ARG_TYPES (f2); | |
481 | ||
482 | /* An unspecified parmlist matches any specified parmlist | |
483 | whose argument types don't need default promotions. */ | |
484 | ||
485 | if (args1 == 0) | |
486 | { | |
487 | if (!self_promoting_args_p (args2)) | |
488 | return 0; | |
489 | /* If one of these types comes from a non-prototype fn definition, | |
490 | compare that with the other type's arglist. | |
491 | If they don't match, ask for a warning (but no error). */ | |
492 | if (TYPE_ACTUAL_ARG_TYPES (f1) | |
493 | && 1 != type_lists_compatible_p (args2, TYPE_ACTUAL_ARG_TYPES (f1))) | |
494 | val = 2; | |
495 | return val; | |
496 | } | |
497 | if (args2 == 0) | |
498 | { | |
499 | if (!self_promoting_args_p (args1)) | |
500 | return 0; | |
501 | if (TYPE_ACTUAL_ARG_TYPES (f2) | |
502 | && 1 != type_lists_compatible_p (args1, TYPE_ACTUAL_ARG_TYPES (f2))) | |
503 | val = 2; | |
504 | return val; | |
505 | } | |
506 | ||
507 | /* Both types have argument lists: compare them and propagate results. */ | |
508 | val1 = type_lists_compatible_p (args1, args2); | |
509 | return val1 != 1 ? val1 : val; | |
510 | } | |
511 | ||
512 | /* Check two lists of types for compatibility, | |
513 | returning 0 for incompatible, 1 for compatible, | |
514 | or 2 for compatible with warning. */ | |
515 | ||
516 | static int | |
517 | type_lists_compatible_p (args1, args2) | |
518 | tree args1, args2; | |
519 | { | |
520 | /* 1 if no need for warning yet, 2 if warning cause has been seen. */ | |
521 | int val = 1; | |
522 | int newval; | |
523 | ||
524 | while (1) | |
525 | { | |
526 | if (args1 == 0 && args2 == 0) | |
527 | return val; | |
528 | /* If one list is shorter than the other, | |
529 | they fail to match. */ | |
530 | if (args1 == 0 || args2 == 0) | |
531 | return 0; | |
532 | /* A null pointer instead of a type | |
533 | means there is supposed to be an argument | |
534 | but nothing is specified about what type it has. | |
535 | So match anything that self-promotes. */ | |
536 | if (TREE_VALUE (args1) == 0) | |
537 | { | |
538 | if (! self_promoting_type_p (TREE_VALUE (args2))) | |
539 | return 0; | |
540 | } | |
541 | else if (TREE_VALUE (args2) == 0) | |
542 | { | |
543 | if (! self_promoting_type_p (TREE_VALUE (args1))) | |
544 | return 0; | |
545 | } | |
546 | else if (! (newval = comptypes (TREE_VALUE (args1), TREE_VALUE (args2)))) | |
547 | { | |
548 | /* Allow wait (union {union wait *u; int *i} *) | |
549 | and wait (union wait *) to be compatible. */ | |
550 | if (TREE_CODE (TREE_VALUE (args1)) == UNION_TYPE | |
551 | && TYPE_NAME (TREE_VALUE (args1)) == 0 | |
552 | && TREE_CODE (TYPE_SIZE (TREE_VALUE (args1))) == INTEGER_CST | |
553 | && tree_int_cst_equal (TYPE_SIZE (TREE_VALUE (args1)), | |
554 | TYPE_SIZE (TREE_VALUE (args2)))) | |
555 | { | |
556 | tree memb; | |
557 | for (memb = TYPE_FIELDS (TREE_VALUE (args1)); | |
558 | memb; memb = TREE_CHAIN (memb)) | |
559 | if (comptypes (TREE_TYPE (memb), TREE_VALUE (args2))) | |
560 | break; | |
561 | if (memb == 0) | |
562 | return 0; | |
563 | } | |
564 | else if (TREE_CODE (TREE_VALUE (args2)) == UNION_TYPE | |
565 | && TYPE_NAME (TREE_VALUE (args2)) == 0 | |
566 | && TREE_CODE (TYPE_SIZE (TREE_VALUE (args2))) == INTEGER_CST | |
567 | && tree_int_cst_equal (TYPE_SIZE (TREE_VALUE (args2)), | |
568 | TYPE_SIZE (TREE_VALUE (args1)))) | |
569 | { | |
570 | tree memb; | |
571 | for (memb = TYPE_FIELDS (TREE_VALUE (args2)); | |
572 | memb; memb = TREE_CHAIN (memb)) | |
573 | if (comptypes (TREE_TYPE (memb), TREE_VALUE (args1))) | |
574 | break; | |
575 | if (memb == 0) | |
576 | return 0; | |
577 | } | |
578 | else | |
579 | return 0; | |
580 | } | |
581 | ||
582 | /* comptypes said ok, but record if it said to warn. */ | |
583 | if (newval > val) | |
584 | val = newval; | |
585 | ||
586 | args1 = TREE_CHAIN (args1); | |
587 | args2 = TREE_CHAIN (args2); | |
588 | } | |
589 | } | |
590 | ||
591 | /* Return 1 if PARMS specifies a fixed number of parameters | |
592 | and none of their types is affected by default promotions. */ | |
593 | ||
805f961c | 594 | int |
400fbf9f JW |
595 | self_promoting_args_p (parms) |
596 | tree parms; | |
597 | { | |
598 | register tree t; | |
599 | for (t = parms; t; t = TREE_CHAIN (t)) | |
600 | { | |
601 | register tree type = TREE_VALUE (t); | |
602 | ||
603 | if (TREE_CHAIN (t) == 0 && type != void_type_node) | |
604 | return 0; | |
605 | ||
606 | if (type == float_type_node) | |
607 | return 0; | |
608 | ||
609 | if (type | |
610 | && TREE_CODE (type) == INTEGER_TYPE | |
611 | && TYPE_PRECISION (type) < TYPE_PRECISION (integer_type_node)) | |
612 | return 0; | |
613 | } | |
614 | return 1; | |
615 | } | |
616 | ||
617 | /* Return 1 if TYPE is not affected by default promotions. */ | |
618 | ||
619 | static int | |
620 | self_promoting_type_p (type) | |
621 | tree type; | |
622 | { | |
623 | if (type == float_type_node) | |
624 | return 0; | |
625 | ||
626 | if (TREE_CODE (type) == INTEGER_TYPE | |
627 | && TYPE_PRECISION (type) < TYPE_PRECISION (integer_type_node)) | |
628 | return 0; | |
629 | ||
630 | return 1; | |
631 | } | |
632 | \f | |
633 | /* Return an unsigned type the same as TYPE in other respects. */ | |
634 | ||
635 | tree | |
636 | unsigned_type (type) | |
637 | tree type; | |
638 | { | |
639 | if (type == signed_char_type_node || type == char_type_node) | |
640 | return unsigned_char_type_node; | |
641 | if (type == integer_type_node) | |
642 | return unsigned_type_node; | |
643 | if (type == short_integer_type_node) | |
644 | return short_unsigned_type_node; | |
645 | if (type == long_integer_type_node) | |
646 | return long_unsigned_type_node; | |
647 | if (type == long_long_integer_type_node) | |
648 | return long_long_unsigned_type_node; | |
649 | return type; | |
650 | } | |
651 | ||
652 | /* Return a signed type the same as TYPE in other respects. */ | |
653 | ||
654 | tree | |
655 | signed_type (type) | |
656 | tree type; | |
657 | { | |
658 | if (type == unsigned_char_type_node || type == char_type_node) | |
659 | return signed_char_type_node; | |
660 | if (type == unsigned_type_node) | |
661 | return integer_type_node; | |
662 | if (type == short_unsigned_type_node) | |
663 | return short_integer_type_node; | |
664 | if (type == long_unsigned_type_node) | |
665 | return long_integer_type_node; | |
666 | if (type == long_long_unsigned_type_node) | |
667 | return long_long_integer_type_node; | |
668 | return type; | |
669 | } | |
670 | ||
671 | /* Return a type the same as TYPE except unsigned or | |
672 | signed according to UNSIGNEDP. */ | |
673 | ||
674 | tree | |
675 | signed_or_unsigned_type (unsignedp, type) | |
676 | int unsignedp; | |
677 | tree type; | |
678 | { | |
679 | if (TREE_CODE (type) != INTEGER_TYPE) | |
680 | return type; | |
681 | if (TYPE_PRECISION (type) == TYPE_PRECISION (signed_char_type_node)) | |
682 | return unsignedp ? unsigned_char_type_node : signed_char_type_node; | |
683 | if (TYPE_PRECISION (type) == TYPE_PRECISION (integer_type_node)) | |
684 | return unsignedp ? unsigned_type_node : integer_type_node; | |
685 | if (TYPE_PRECISION (type) == TYPE_PRECISION (short_integer_type_node)) | |
686 | return unsignedp ? short_unsigned_type_node : short_integer_type_node; | |
687 | if (TYPE_PRECISION (type) == TYPE_PRECISION (long_integer_type_node)) | |
688 | return unsignedp ? long_unsigned_type_node : long_integer_type_node; | |
689 | if (TYPE_PRECISION (type) == TYPE_PRECISION (long_long_integer_type_node)) | |
690 | return (unsignedp ? long_long_unsigned_type_node | |
691 | : long_long_integer_type_node); | |
692 | return type; | |
693 | } | |
694 | ||
695 | /* Compute the value of the `sizeof' operator. */ | |
696 | ||
697 | tree | |
698 | c_sizeof (type) | |
699 | tree type; | |
700 | { | |
701 | enum tree_code code = TREE_CODE (type); | |
702 | ||
703 | if (code == FUNCTION_TYPE) | |
704 | { | |
705 | if (pedantic || warn_pointer_arith) | |
706 | pedwarn ("sizeof applied to a function type"); | |
707 | return size_int (1); | |
708 | } | |
709 | if (code == VOID_TYPE) | |
710 | { | |
711 | if (pedantic || warn_pointer_arith) | |
712 | pedwarn ("sizeof applied to a void type"); | |
713 | return size_int (1); | |
714 | } | |
715 | if (code == ERROR_MARK) | |
716 | return size_int (1); | |
717 | if (TYPE_SIZE (type) == 0) | |
718 | { | |
719 | error ("sizeof applied to an incomplete type"); | |
720 | return size_int (0); | |
721 | } | |
722 | ||
723 | /* Convert in case a char is more than one unit. */ | |
724 | return size_binop (CEIL_DIV_EXPR, TYPE_SIZE (type), | |
725 | size_int (TYPE_PRECISION (char_type_node))); | |
726 | } | |
727 | ||
728 | tree | |
729 | c_sizeof_nowarn (type) | |
730 | tree type; | |
731 | { | |
732 | enum tree_code code = TREE_CODE (type); | |
733 | ||
734 | if (code == FUNCTION_TYPE | |
735 | || code == VOID_TYPE | |
736 | || code == ERROR_MARK) | |
737 | return size_int (1); | |
738 | if (TYPE_SIZE (type) == 0) | |
739 | return size_int (0); | |
740 | ||
741 | /* Convert in case a char is more than one unit. */ | |
742 | return size_binop (CEIL_DIV_EXPR, TYPE_SIZE (type), | |
743 | size_int (TYPE_PRECISION (char_type_node))); | |
744 | } | |
745 | ||
746 | /* Compute the size to increment a pointer by. */ | |
747 | ||
748 | tree | |
749 | c_size_in_bytes (type) | |
750 | tree type; | |
751 | { | |
752 | enum tree_code code = TREE_CODE (type); | |
753 | ||
754 | if (code == FUNCTION_TYPE) | |
755 | return size_int (1); | |
756 | if (code == VOID_TYPE) | |
757 | return size_int (1); | |
758 | if (code == ERROR_MARK) | |
759 | return size_int (1); | |
760 | if (TYPE_SIZE (type) == 0) | |
761 | { | |
762 | error ("arithmetic on pointer to an incomplete type"); | |
763 | return size_int (1); | |
764 | } | |
765 | ||
766 | /* Convert in case a char is more than one unit. */ | |
767 | return size_binop (CEIL_DIV_EXPR, TYPE_SIZE (type), | |
768 | size_int (BITS_PER_UNIT)); | |
769 | } | |
770 | ||
771 | /* Implement the __alignof keyword: Return the minimum required | |
772 | alignment of TYPE, measured in bytes. */ | |
773 | ||
774 | tree | |
775 | c_alignof (type) | |
776 | tree type; | |
777 | { | |
778 | enum tree_code code = TREE_CODE (type); | |
779 | ||
780 | if (code == FUNCTION_TYPE) | |
781 | return size_int (FUNCTION_BOUNDARY / BITS_PER_UNIT); | |
782 | ||
783 | if (code == VOID_TYPE || code == ERROR_MARK) | |
784 | return size_int (1); | |
785 | ||
786 | return size_int (TYPE_ALIGN (type) / BITS_PER_UNIT); | |
787 | } | |
26b3c423 RS |
788 | |
789 | /* Print a warning if a constant expression had overflow in folding. | |
790 | This doesn't really work--it is waiting for changes in fold. */ | |
791 | ||
792 | void | |
793 | constant_expression_warning (value) | |
794 | tree value; | |
795 | { | |
796 | if (TREE_CODE (value) == NON_LVALUE_EXPR && TREE_CONSTANT_OVERFLOW (value)) | |
797 | pedwarn ("overflow in constant expression"); | |
798 | } | |
400fbf9f JW |
799 | \f |
800 | /* Implement the __alignof keyword: Return the minimum required | |
801 | alignment of EXPR, measured in bytes. For VAR_DECL's and | |
802 | FIELD_DECL's return DECL_ALIGN (which can be set from an | |
803 | "aligned" __attribute__ specification). */ | |
804 | tree | |
805 | c_alignof_expr (expr) | |
806 | tree expr; | |
807 | { | |
808 | if (TREE_CODE (expr) == VAR_DECL) | |
809 | return size_int (DECL_ALIGN (expr) / BITS_PER_UNIT); | |
810 | ||
811 | if (TREE_CODE (expr) == COMPONENT_REF | |
812 | && DECL_BIT_FIELD (TREE_OPERAND (expr, 1))) | |
813 | { | |
814 | error ("`__alignof' applied to a bit-field"); | |
815 | return size_int (1); | |
816 | } | |
817 | else if (TREE_CODE (expr) == COMPONENT_REF | |
818 | && TREE_CODE (TREE_OPERAND (expr, 1)) == FIELD_DECL) | |
819 | return size_int (DECL_ALIGN (TREE_OPERAND (expr, 1)) / BITS_PER_UNIT); | |
820 | ||
821 | if (TREE_CODE (expr) == INDIRECT_REF) | |
822 | { | |
823 | tree t = TREE_OPERAND (expr, 0); | |
824 | tree best = t; | |
825 | int bestalign = TYPE_ALIGN (TREE_TYPE (TREE_TYPE (t))); | |
826 | ||
827 | while (TREE_CODE (t) == NOP_EXPR | |
828 | && TREE_CODE (TREE_TYPE (TREE_OPERAND (t, 0))) == POINTER_TYPE) | |
829 | { | |
830 | int thisalign; | |
831 | ||
832 | t = TREE_OPERAND (t, 0); | |
833 | thisalign = TYPE_ALIGN (TREE_TYPE (TREE_TYPE (t))); | |
834 | if (thisalign > bestalign) | |
835 | best = t, bestalign = thisalign; | |
836 | } | |
837 | return c_alignof (TREE_TYPE (TREE_TYPE (best))); | |
838 | } | |
839 | else | |
840 | return c_alignof (TREE_TYPE (expr)); | |
841 | } | |
842 | /* Return either DECL or its known constant value (if it has one). */ | |
843 | ||
844 | static tree | |
845 | decl_constant_value (decl) | |
846 | tree decl; | |
847 | { | |
848 | if (! TREE_PUBLIC (decl) | |
849 | /* Don't change a variable array bound or initial value to a constant | |
850 | in a place where a variable is invalid. */ | |
851 | && current_function_decl != 0 | |
852 | && ! pedantic | |
853 | && ! TREE_THIS_VOLATILE (decl) | |
854 | && DECL_INITIAL (decl) != 0 | |
855 | && TREE_CODE (DECL_INITIAL (decl)) != ERROR_MARK | |
856 | /* This is invalid if initial value is not constant. | |
857 | If it has either a function call, a memory reference, | |
858 | or a variable, then re-evaluating it could give different results. */ | |
859 | && TREE_CONSTANT (DECL_INITIAL (decl)) | |
860 | /* Check for cases where this is sub-optimal, even though valid. */ | |
861 | && TREE_CODE (DECL_INITIAL (decl)) != CONSTRUCTOR | |
862 | && DECL_MODE (decl) != BLKmode) | |
863 | return DECL_INITIAL (decl); | |
864 | return decl; | |
865 | } | |
866 | ||
867 | /* Perform default promotions for C data used in expressions. | |
868 | Arrays and functions are converted to pointers; | |
869 | enumeral types or short or char, to int. | |
870 | In addition, manifest constants symbols are replaced by their values. */ | |
871 | ||
872 | tree | |
873 | default_conversion (exp) | |
874 | tree exp; | |
875 | { | |
876 | register tree type = TREE_TYPE (exp); | |
877 | register enum tree_code code = TREE_CODE (type); | |
878 | ||
879 | /* Constants can be used directly unless they're not loadable. */ | |
880 | if (TREE_CODE (exp) == CONST_DECL) | |
881 | exp = DECL_INITIAL (exp); | |
882 | /* Replace a nonvolatile const static variable with its value. */ | |
883 | else if (optimize | |
884 | && TREE_CODE (exp) == VAR_DECL | |
885 | && TREE_READONLY (exp) | |
886 | && DECL_MODE (exp) != BLKmode) | |
887 | { | |
888 | exp = decl_constant_value (exp); | |
889 | type = TREE_TYPE (exp); | |
890 | } | |
891 | ||
892 | /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */ | |
893 | if (TREE_CODE (exp) == NON_LVALUE_EXPR) | |
894 | exp = TREE_OPERAND (exp, 0); | |
895 | ||
896 | /* Normally convert enums to int, | |
897 | but convert wide enums to something wider. */ | |
898 | if (code == ENUMERAL_TYPE) | |
899 | { | |
900 | type = type_for_size (MAX (TYPE_PRECISION (type), | |
901 | TYPE_PRECISION (integer_type_node)), | |
902 | (flag_traditional && TREE_UNSIGNED (type))); | |
903 | return convert (type, exp); | |
904 | } | |
905 | ||
906 | if (code == INTEGER_TYPE | |
907 | && (TYPE_PRECISION (type) | |
908 | < TYPE_PRECISION (integer_type_node))) | |
909 | { | |
910 | /* Traditionally, unsignedness is preserved in default promotions. */ | |
911 | if (flag_traditional && TREE_UNSIGNED (type)) | |
912 | return convert (unsigned_type_node, exp); | |
913 | return convert (integer_type_node, exp); | |
914 | } | |
915 | if (flag_traditional && type == float_type_node) | |
916 | return convert (double_type_node, exp); | |
917 | if (code == VOID_TYPE) | |
918 | { | |
919 | error ("void value not ignored as it ought to be"); | |
920 | return error_mark_node; | |
921 | } | |
922 | if (code == FUNCTION_TYPE) | |
923 | { | |
924 | return build_unary_op (ADDR_EXPR, exp, 0); | |
925 | } | |
926 | if (code == ARRAY_TYPE) | |
927 | { | |
928 | register tree adr; | |
929 | tree restype = TREE_TYPE (type); | |
930 | tree ptrtype; | |
931 | ||
932 | if (TREE_CODE (exp) == INDIRECT_REF) | |
933 | return convert (TYPE_POINTER_TO (restype), | |
934 | TREE_OPERAND (exp, 0)); | |
935 | ||
936 | if (TREE_CODE (exp) == COMPOUND_EXPR) | |
937 | { | |
938 | tree op1 = default_conversion (TREE_OPERAND (exp, 1)); | |
939 | return build (COMPOUND_EXPR, TREE_TYPE (op1), | |
940 | TREE_OPERAND (exp, 0), op1); | |
941 | } | |
942 | ||
943 | if (!lvalue_p (exp) | |
944 | && ! (TREE_CODE (exp) == CONSTRUCTOR && TREE_STATIC (exp))) | |
945 | { | |
946 | error ("invalid use of non-lvalue array"); | |
947 | return error_mark_node; | |
948 | } | |
949 | ||
950 | if (TYPE_READONLY (type) || TYPE_VOLATILE (type)) | |
951 | restype = c_build_type_variant (restype, TYPE_READONLY (type), | |
952 | TYPE_VOLATILE (type)); | |
953 | ||
954 | ptrtype = build_pointer_type (restype); | |
955 | ||
956 | if (TREE_CODE (exp) == VAR_DECL) | |
957 | { | |
958 | /* ??? This is not really quite correct | |
959 | in that the type of the operand of ADDR_EXPR | |
960 | is not the target type of the type of the ADDR_EXPR itself. | |
961 | Question is, can this lossage be avoided? */ | |
962 | adr = build1 (ADDR_EXPR, ptrtype, exp); | |
963 | if (mark_addressable (exp) == 0) | |
964 | return error_mark_node; | |
965 | TREE_CONSTANT (adr) = staticp (exp); | |
966 | TREE_SIDE_EFFECTS (adr) = 0; /* Default would be, same as EXP. */ | |
967 | return adr; | |
968 | } | |
969 | /* This way is better for a COMPONENT_REF since it can | |
970 | simplify the offset for a component. */ | |
971 | adr = build_unary_op (ADDR_EXPR, exp, 1); | |
972 | return convert (ptrtype, adr); | |
973 | } | |
974 | return exp; | |
975 | } | |
976 | \f | |
977 | /* Make an expression to refer to the COMPONENT field of | |
978 | structure or union value DATUM. COMPONENT is an IDENTIFIER_NODE. */ | |
979 | ||
980 | tree | |
981 | build_component_ref (datum, component) | |
982 | tree datum, component; | |
983 | { | |
984 | register tree type = TREE_TYPE (datum); | |
985 | register enum tree_code code = TREE_CODE (type); | |
986 | register tree field = NULL; | |
987 | register tree ref; | |
988 | ||
989 | /* If DATUM is a COMPOUND_EXPR or COND_EXPR, move our reference inside it | |
990 | unless we are not to support things not strictly ANSI. */ | |
991 | switch (TREE_CODE (datum)) | |
992 | { | |
993 | case COMPOUND_EXPR: | |
994 | { | |
995 | tree value = build_component_ref (TREE_OPERAND (datum, 1), component); | |
996 | pedantic_lvalue_warning (COMPOUND_EXPR); | |
997 | return build (COMPOUND_EXPR, TREE_TYPE (value), | |
998 | TREE_OPERAND (datum, 0), value); | |
999 | } | |
1000 | case COND_EXPR: | |
1001 | pedantic_lvalue_warning (COND_EXPR); | |
1002 | return build_conditional_expr | |
1003 | (TREE_OPERAND (datum, 0), | |
1004 | build_component_ref (TREE_OPERAND (datum, 1), component), | |
1005 | build_component_ref (TREE_OPERAND (datum, 2), component)); | |
1006 | } | |
1007 | ||
1008 | /* See if there is a field or component with name COMPONENT. */ | |
1009 | ||
1010 | if (code == RECORD_TYPE || code == UNION_TYPE) | |
1011 | { | |
1012 | if (TYPE_SIZE (type) == 0) | |
1013 | { | |
1014 | incomplete_type_error (0, type); | |
1015 | return error_mark_node; | |
1016 | } | |
1017 | ||
1018 | /* Look up component name in the structure type definition. | |
1019 | ||
1020 | If TYPE_LANG_SPECIFIC is set, then it is a sorted array of pointers | |
1021 | to the field elements. Use a binary search on this array to quickly | |
1022 | find the element. Otherwise, do a linear search. TYPE_LANG_SPECIFIC | |
1023 | will always be set for structures which have many elements. */ | |
1024 | ||
1025 | if (TYPE_LANG_SPECIFIC (type)) | |
1026 | { | |
1027 | int bot, top, half; | |
1028 | tree *field_array = &TYPE_LANG_SPECIFIC (type)->elts[0]; | |
1029 | ||
1030 | field = TYPE_FIELDS (type); | |
1031 | bot = 0; | |
1032 | top = TYPE_LANG_SPECIFIC (type)->len; | |
1033 | while (top - bot > 1) | |
1034 | { | |
1035 | int cmp; | |
1036 | ||
1037 | half = (top - bot + 1) >> 1; | |
1038 | field = field_array[bot+half]; | |
1039 | cmp = (long)DECL_NAME (field) - (long)component; | |
1040 | if (cmp == 0) | |
1041 | break; | |
1042 | if (cmp < 0) | |
1043 | bot += half; | |
1044 | else | |
1045 | top = bot + half; | |
1046 | } | |
1047 | ||
1048 | if (DECL_NAME (field_array[bot]) == component) | |
1049 | field = field_array[bot]; | |
1050 | else if (DECL_NAME (field) != component) | |
1051 | field = 0; | |
1052 | } | |
1053 | else | |
1054 | { | |
1055 | for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field)) | |
1056 | { | |
1057 | if (DECL_NAME (field) == component) | |
1058 | break; | |
1059 | } | |
1060 | } | |
1061 | ||
1062 | if (!field) | |
1063 | { | |
1064 | error (code == RECORD_TYPE | |
1065 | ? "structure has no member named `%s'" | |
1066 | : "union has no member named `%s'", | |
1067 | IDENTIFIER_POINTER (component)); | |
1068 | return error_mark_node; | |
1069 | } | |
1070 | if (TREE_TYPE (field) == error_mark_node) | |
1071 | return error_mark_node; | |
1072 | ||
1073 | ref = build (COMPONENT_REF, TREE_TYPE (field), datum, field); | |
1074 | ||
1075 | if (TREE_READONLY (datum) || TREE_READONLY (field)) | |
1076 | TREE_READONLY (ref) = 1; | |
1077 | if (TREE_THIS_VOLATILE (datum) || TREE_THIS_VOLATILE (field)) | |
1078 | TREE_THIS_VOLATILE (ref) = 1; | |
1079 | ||
1080 | return ref; | |
1081 | } | |
1082 | else if (code != ERROR_MARK) | |
1083 | error ("request for member `%s' in something not a structure or union", | |
1084 | IDENTIFIER_POINTER (component)); | |
1085 | ||
1086 | return error_mark_node; | |
1087 | } | |
1088 | \f | |
1089 | /* Given an expression PTR for a pointer, return an expression | |
1090 | for the value pointed to. | |
1091 | ERRORSTRING is the name of the operator to appear in error messages. */ | |
1092 | ||
1093 | tree | |
1094 | build_indirect_ref (ptr, errorstring) | |
1095 | tree ptr; | |
1096 | char *errorstring; | |
1097 | { | |
1098 | register tree pointer = default_conversion (ptr); | |
1099 | register tree type = TREE_TYPE (pointer); | |
1100 | ||
1101 | if (TREE_CODE (type) == POINTER_TYPE) | |
1102 | if (TREE_CODE (pointer) == ADDR_EXPR | |
1103 | && (TREE_TYPE (TREE_OPERAND (pointer, 0)) | |
1104 | == TREE_TYPE (type))) | |
1105 | return TREE_OPERAND (pointer, 0); | |
1106 | else | |
1107 | { | |
1108 | tree t = TREE_TYPE (type); | |
1109 | register tree ref = build1 (INDIRECT_REF, | |
1110 | TYPE_MAIN_VARIANT (t), pointer); | |
1111 | ||
1112 | if (TREE_CODE (t) == VOID_TYPE | |
1113 | || (TYPE_SIZE (t) == 0 && TREE_CODE (t) != ARRAY_TYPE)) | |
1114 | { | |
1115 | error ("dereferencing pointer to incomplete type"); | |
1116 | return error_mark_node; | |
1117 | } | |
1118 | ||
d45cf215 | 1119 | /* We *must* set TREE_READONLY when dereferencing a pointer to const, |
400fbf9f JW |
1120 | so that we get the proper error message if the result is used |
1121 | to assign to. Also, &* is supposed to be a no-op. | |
1122 | And ANSI C seems to specify that the type of the result | |
1123 | should be the const type. */ | |
1124 | /* A de-reference of a pointer to const is not a const. It is valid | |
1125 | to change it via some other pointer. */ | |
1126 | TREE_READONLY (ref) = TYPE_READONLY (t); | |
1127 | TREE_SIDE_EFFECTS (ref) = TYPE_VOLATILE (t) || TREE_SIDE_EFFECTS (pointer); | |
1128 | TREE_THIS_VOLATILE (ref) = TYPE_VOLATILE (t); | |
1129 | return ref; | |
1130 | } | |
1131 | else if (TREE_CODE (pointer) != ERROR_MARK) | |
1132 | error ("invalid type argument of `%s'", errorstring); | |
1133 | return error_mark_node; | |
1134 | } | |
1135 | ||
1136 | /* This handles expressions of the form "a[i]", which denotes | |
1137 | an array reference. | |
1138 | ||
1139 | This is logically equivalent in C to *(a+i), but we may do it differently. | |
1140 | If A is a variable or a member, we generate a primitive ARRAY_REF. | |
1141 | This avoids forcing the array out of registers, and can work on | |
1142 | arrays that are not lvalues (for example, members of structures returned | |
1143 | by functions). */ | |
1144 | ||
1145 | tree | |
1146 | build_array_ref (array, index) | |
1147 | tree array, index; | |
1148 | { | |
1149 | if (index == 0) | |
1150 | { | |
1151 | error ("subscript missing in array reference"); | |
1152 | return error_mark_node; | |
1153 | } | |
1154 | ||
1155 | if (TREE_TYPE (array) == error_mark_node | |
1156 | || TREE_TYPE (index) == error_mark_node) | |
1157 | return error_mark_node; | |
1158 | ||
1159 | if (TREE_CODE (TREE_TYPE (array)) == ARRAY_TYPE | |
1160 | && TREE_CODE (array) != INDIRECT_REF) | |
1161 | { | |
1162 | tree rval, type; | |
1163 | ||
400fbf9f JW |
1164 | /* Subscripting with type char is likely to lose |
1165 | on a machine where chars are signed. | |
1166 | So warn on any machine, but optionally. | |
1167 | Don't warn for unsigned char since that type is safe. | |
1168 | Don't warn for signed char because anyone who uses that | |
1169 | must have done so deliberately. */ | |
1170 | if (warn_char_subscripts | |
1171 | && TYPE_MAIN_VARIANT (TREE_TYPE (index)) == char_type_node) | |
1172 | warning ("array subscript has type `char'"); | |
1173 | ||
0e51ef9b RS |
1174 | /* Apply default promotions *after* noticing character types. */ |
1175 | index = default_conversion (index); | |
1176 | ||
fdeefd49 RS |
1177 | /* Require integer *after* promotion, for sake of enums. */ |
1178 | if (TREE_CODE (TREE_TYPE (index)) != INTEGER_TYPE) | |
1179 | { | |
1180 | error ("array subscript is not an integer"); | |
1181 | return error_mark_node; | |
1182 | } | |
1183 | ||
400fbf9f JW |
1184 | /* An array that is indexed by a non-constant |
1185 | cannot be stored in a register; we must be able to do | |
1186 | address arithmetic on its address. | |
1187 | Likewise an array of elements of variable size. */ | |
1188 | if (TREE_CODE (index) != INTEGER_CST | |
1189 | || (TYPE_SIZE (TREE_TYPE (TREE_TYPE (array))) != 0 | |
1190 | && TREE_CODE (TYPE_SIZE (TREE_TYPE (TREE_TYPE (array)))) != INTEGER_CST)) | |
1191 | { | |
1192 | if (mark_addressable (array) == 0) | |
1193 | return error_mark_node; | |
1194 | } | |
1195 | ||
1196 | if (pedantic && !lvalue_p (array)) | |
1197 | { | |
1198 | if (TREE_REGDECL (array)) | |
1199 | pedwarn ("ANSI C forbids subscripting `register' array"); | |
1200 | else | |
1201 | pedwarn ("ANSI C forbids subscripting non-lvalue array"); | |
1202 | } | |
1203 | ||
1204 | if (pedantic) | |
1205 | { | |
1206 | tree foo = array; | |
1207 | while (TREE_CODE (foo) == COMPONENT_REF) | |
1208 | foo = TREE_OPERAND (foo, 0); | |
1209 | if (TREE_CODE (foo) == VAR_DECL && TREE_REGDECL (foo)) | |
1210 | pedwarn ("ANSI C forbids subscripting non-lvalue array"); | |
1211 | } | |
1212 | ||
1213 | type = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (array))); | |
1214 | rval = build (ARRAY_REF, type, array, index); | |
1215 | /* Array ref is const/volatile if the array elements are | |
1216 | or if the array is. */ | |
1217 | TREE_READONLY (rval) | |
1218 | |= (TYPE_READONLY (TREE_TYPE (TREE_TYPE (array))) | |
1219 | | TREE_READONLY (array)); | |
1220 | TREE_SIDE_EFFECTS (rval) | |
1221 | |= (TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (array))) | |
1222 | | TREE_SIDE_EFFECTS (array)); | |
1223 | TREE_THIS_VOLATILE (rval) | |
1224 | |= (TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (array))) | |
1225 | /* This was added by rms on 16 Nov 91. | |
1226 | It fixes vol struct foo *a; a->elts[1] | |
1227 | in an inline function. | |
1228 | Hope it doesn't break something else. */ | |
1229 | | TREE_THIS_VOLATILE (array)); | |
1230 | return require_complete_type (fold (rval)); | |
1231 | } | |
1232 | ||
1233 | { | |
1234 | tree ar = default_conversion (array); | |
1235 | tree ind = default_conversion (index); | |
1236 | ||
1237 | /* Put the integer in IND to simplify error checking. */ | |
1238 | if (TREE_CODE (TREE_TYPE (ar)) == INTEGER_TYPE) | |
1239 | { | |
1240 | tree temp = ar; | |
1241 | ar = ind; | |
1242 | ind = temp; | |
1243 | } | |
1244 | ||
1245 | if (ar == error_mark_node) | |
1246 | return ar; | |
1247 | ||
1248 | if (TREE_CODE (TREE_TYPE (ar)) != POINTER_TYPE) | |
1249 | { | |
1250 | error ("subscripted value is neither array nor pointer"); | |
1251 | return error_mark_node; | |
1252 | } | |
1253 | if (TREE_CODE (TREE_TYPE (ind)) != INTEGER_TYPE) | |
1254 | { | |
1255 | error ("array subscript is not an integer"); | |
1256 | return error_mark_node; | |
1257 | } | |
1258 | ||
1259 | return build_indirect_ref (build_binary_op (PLUS_EXPR, ar, ind, 0), | |
1260 | "array indexing"); | |
1261 | } | |
1262 | } | |
1263 | \f | |
1264 | /* Check a printf/fprintf/sprintf/scanf/fscanf/sscanf format against PARAMS. */ | |
1265 | ||
1266 | #define ISDIGIT(c) ((c) >= '0' && (c) <= '9') | |
1267 | ||
1268 | #define T_I &integer_type_node | |
1269 | #define T_L &long_integer_type_node | |
1270 | #define T_S &short_integer_type_node | |
1271 | #define T_UI &unsigned_type_node | |
1272 | #define T_UL &long_unsigned_type_node | |
1273 | #define T_US &short_unsigned_type_node | |
1274 | #define T_F &float_type_node | |
1275 | #define T_D &double_type_node | |
1276 | #define T_LD &long_double_type_node | |
1277 | #define T_C &char_type_node | |
1278 | #define T_V &void_type_node | |
1279 | ||
1280 | typedef struct | |
1281 | { | |
1282 | char *format_chars; | |
1283 | int pointer_count; | |
1284 | /* Type of argument if no length modifier is used. */ | |
1285 | tree *nolen; | |
1286 | /* Type of argument if length modifier for shortening is used. | |
1287 | If NULL, then this modifier is not allowed. */ | |
1288 | tree *hlen; | |
1289 | /* Type of argument if length modifier `l' is used. | |
1290 | If NULL, then this modifier is not allowed. */ | |
1291 | tree *llen; | |
1292 | /* Type of argument if length modifier `L' is used. | |
1293 | If NULL, then this modifier is not allowed. */ | |
1294 | tree *bigllen; | |
1295 | /* List of other modifier characters allowed with these options. */ | |
1296 | char *flag_chars; | |
1297 | } format_char_info; | |
1298 | ||
1299 | static format_char_info print_table[] | |
1300 | = { | |
1301 | { "di", 0, T_I, T_I, T_L, NULL, "-wp0 +" }, | |
1302 | { "oxX", 0, T_UI, T_UI, T_UL, NULL, "-wp0#" }, | |
1303 | { "u", 0, T_UI, T_UI, T_UL, NULL, "-wp0" }, | |
1304 | { "feEgG", 0, T_D, NULL, NULL, T_LD, "-wp0 +#" }, | |
1305 | { "c", 0, T_I, NULL, NULL, NULL, "-w" }, | |
1306 | { "s", 1, T_C, NULL, NULL, NULL, "-wp" }, | |
1307 | { "p", 1, T_V, NULL, NULL, NULL, "-" }, | |
1308 | { "n", 1, T_I, T_S, T_L, NULL, "" }, | |
1309 | { NULL } | |
1310 | }; | |
1311 | ||
1312 | static format_char_info scan_table[] | |
1313 | = { | |
1314 | { "di", 1, T_I, T_S, T_L, NULL, "*" }, | |
1315 | { "ouxX", 1, T_UI, T_US, T_UL, NULL, "*" }, | |
1316 | { "efgEG", 1, T_F, NULL, T_D, T_LD, "*" }, | |
1317 | { "s[c", 1, T_C, NULL, NULL, NULL, "*" }, | |
1318 | { "p", 2, T_V, NULL, NULL, NULL, "*" }, | |
1319 | { "n", 1, T_I, T_S, T_L, NULL, "" }, | |
1320 | { NULL } | |
1321 | }; | |
1322 | ||
1323 | typedef struct | |
1324 | { | |
1325 | tree function_ident; /* identifier such as "printf" */ | |
1326 | int is_scan; /* TRUE if *scanf */ | |
1327 | int format_num; /* number of format argument */ | |
1328 | int first_arg_num; /* number of first arg (zero for varargs) */ | |
1329 | } function_info; | |
1330 | ||
1331 | static unsigned int function_info_entries = 0; | |
1332 | static function_info *function_info_table = NULL; | |
1333 | ||
1334 | /* Record information for argument format checking. FUNCTION_IDENT is | |
1335 | the identifier node for the name of the function to check (its decl | |
1336 | need not exist yet). IS_SCAN is true for scanf-type format checking; | |
1337 | false indicates printf-style format checking. FORMAT_NUM is the number | |
1338 | of the argument which is the format control string (starting from 1). | |
1339 | FIRST_ARG_NUM is the number of the first actual argument to check | |
1340 | against teh format string, or zero if no checking is not be done | |
1341 | (e.g. for varargs such as vfprintf). */ | |
1342 | ||
1343 | void | |
1344 | record_format_info (function_ident, is_scan, format_num, first_arg_num) | |
1345 | tree function_ident; | |
1346 | int is_scan; | |
1347 | int format_num; | |
1348 | int first_arg_num; | |
1349 | { | |
1350 | function_info *info; | |
1351 | ||
1352 | function_info_entries++; | |
1353 | if (function_info_table) | |
1354 | function_info_table | |
1355 | = (function_info *) xrealloc (function_info_table, | |
1356 | function_info_entries * sizeof (function_info)); | |
1357 | else | |
1358 | function_info_table = (function_info *) xmalloc (sizeof (function_info)); | |
1359 | ||
1360 | info = &function_info_table[function_info_entries - 1]; | |
1361 | ||
1362 | info->function_ident = function_ident; | |
1363 | info->is_scan = is_scan; | |
1364 | info->format_num = format_num; | |
1365 | info->first_arg_num = first_arg_num; | |
1366 | } | |
1367 | ||
1368 | /* Initialize the table of functions to perform format checking on. | |
1369 | The ANSI functions are always checked (whether <stdio.h> is | |
1370 | included or not), since it is common to call printf without | |
1371 | including <stdio.h>. There shouldn't be a problem with this, | |
1372 | since ANSI reserves these function names whether you include the | |
1373 | header file or not. In any case, the checking is harmless. */ | |
1374 | ||
1375 | void | |
1376 | init_format_info_table () | |
1377 | { | |
1378 | record_format_info (get_identifier ("printf"), 0, 1, 2); | |
1379 | record_format_info (get_identifier ("fprintf"), 0, 2, 3); | |
1380 | record_format_info (get_identifier ("sprintf"), 0, 2, 3); | |
1381 | record_format_info (get_identifier ("scanf"), 1, 1, 2); | |
1382 | record_format_info (get_identifier ("fscanf"), 1, 2, 3); | |
1383 | record_format_info (get_identifier ("sscanf"), 1, 2, 3); | |
1384 | record_format_info (get_identifier ("vprintf"), 0, 1, 0); | |
1385 | record_format_info (get_identifier ("vfprintf"), 0, 2, 0); | |
1386 | record_format_info (get_identifier ("vsprintf"), 0, 2, 0); | |
1387 | } | |
1388 | ||
1389 | static char tfaff[] = "too few arguments for format"; | |
400fbf9f JW |
1390 | \f |
1391 | /* Check the argument list of a call to printf, scanf, etc. | |
1392 | INFO points to the element of function_info_table. | |
1393 | PARAMS is the list of argument values. */ | |
1394 | ||
1395 | static void | |
1396 | check_format (info, params) | |
1397 | function_info *info; | |
1398 | tree params; | |
1399 | { | |
1400 | int i; | |
1401 | int arg_num; | |
1402 | int suppressed, wide, precise; | |
1403 | int length_char; | |
1404 | int format_char; | |
1405 | int format_length; | |
1406 | tree format_tree; | |
1407 | tree cur_param; | |
1408 | tree cur_type; | |
1409 | tree wanted_type; | |
1410 | char *format_chars; | |
1411 | format_char_info *fci; | |
1412 | static char message[132]; | |
1413 | char flag_chars[8]; | |
1414 | ||
1415 | /* Skip to format argument. If the argument isn't available, there's | |
1416 | no work for us to do; prototype checking will catch the problem. */ | |
1417 | for (arg_num = 1; ; ++arg_num) | |
1418 | { | |
1419 | if (params == 0) | |
1420 | return; | |
1421 | if (arg_num == info->format_num) | |
1422 | break; | |
1423 | params = TREE_CHAIN (params); | |
1424 | } | |
1425 | format_tree = TREE_VALUE (params); | |
1426 | params = TREE_CHAIN (params); | |
1427 | if (format_tree == 0) | |
1428 | return; | |
1429 | /* We can only check the format if it's a string constant. */ | |
1430 | while (TREE_CODE (format_tree) == NOP_EXPR) | |
1431 | format_tree = TREE_OPERAND (format_tree, 0); /* strip coercion */ | |
1432 | if (format_tree == null_pointer_node) | |
1433 | { | |
1434 | warning ("null format string"); | |
1435 | return; | |
1436 | } | |
1437 | if (TREE_CODE (format_tree) != ADDR_EXPR) | |
1438 | return; | |
1439 | format_tree = TREE_OPERAND (format_tree, 0); | |
1440 | if (TREE_CODE (format_tree) != STRING_CST) | |
1441 | return; | |
1442 | format_chars = TREE_STRING_POINTER (format_tree); | |
1443 | format_length = TREE_STRING_LENGTH (format_tree); | |
1444 | if (format_length <= 1) | |
1445 | warning ("zero-length format string"); | |
1446 | if (format_chars[--format_length] != 0) | |
1447 | { | |
1448 | warning ("unterminated format string"); | |
1449 | return; | |
1450 | } | |
1451 | /* Skip to first argument to check. */ | |
1452 | while (arg_num + 1 < info->first_arg_num) | |
1453 | { | |
1454 | if (params == 0) | |
1455 | return; | |
1456 | params = TREE_CHAIN (params); | |
1457 | ++arg_num; | |
1458 | } | |
1459 | while (1) | |
1460 | { | |
1461 | if (*format_chars == 0) | |
1462 | { | |
1463 | if (format_chars - TREE_STRING_POINTER (format_tree) != format_length) | |
1464 | warning ("embedded `\\0' in format"); | |
1465 | if (info->first_arg_num != 0 && params != 0) | |
1466 | warning ("too many arguments for format"); | |
1467 | return; | |
1468 | } | |
1469 | if (*format_chars++ != '%') | |
1470 | continue; | |
1471 | if (*format_chars == 0) | |
1472 | { | |
1473 | warning ("spurious trailing `%%' in format"); | |
1474 | continue; | |
1475 | } | |
1476 | if (*format_chars == '%') | |
1477 | { | |
1478 | ++format_chars; | |
1479 | continue; | |
1480 | } | |
1481 | flag_chars[0] = 0; | |
1482 | suppressed = wide = precise = FALSE; | |
1483 | if (info->is_scan) | |
1484 | { | |
1485 | suppressed = *format_chars == '*'; | |
1486 | if (suppressed) | |
1487 | ++format_chars; | |
1488 | while (ISDIGIT (*format_chars)) | |
1489 | ++format_chars; | |
1490 | } | |
1491 | else | |
1492 | { | |
3845b542 | 1493 | while (*format_chars != 0 && index (" +#0-", *format_chars) != 0) |
400fbf9f | 1494 | { |
3845b542 | 1495 | if (index (flag_chars, *format_chars) != 0) |
400fbf9f JW |
1496 | { |
1497 | sprintf (message, "repeated `%c' flag in format", | |
1498 | *format_chars); | |
1499 | warning (message); | |
1500 | } | |
1501 | i = strlen (flag_chars); | |
1502 | flag_chars[i++] = *format_chars++; | |
1503 | flag_chars[i] = 0; | |
1504 | } | |
1505 | /* "If the space and + flags both appear, | |
1506 | the space flag will be ignored." */ | |
3845b542 MS |
1507 | if (index (flag_chars, ' ') != 0 |
1508 | && index (flag_chars, '+') != 0) | |
400fbf9f JW |
1509 | warning ("use of both ` ' and `+' flags in format"); |
1510 | /* "If the 0 and - flags both appear, | |
1511 | the 0 flag will be ignored." */ | |
3845b542 MS |
1512 | if (index (flag_chars, '0') != 0 |
1513 | && index (flag_chars, '-') != 0) | |
400fbf9f JW |
1514 | warning ("use of both `0' and `-' flags in format"); |
1515 | if (*format_chars == '*') | |
1516 | { | |
1517 | wide = TRUE; | |
1518 | /* "...a field width...may be indicated by an asterisk. | |
1519 | In this case, an int argument supplies the field width..." */ | |
1520 | ++format_chars; | |
1521 | if (params == 0) | |
1522 | { | |
1523 | warning (tfaff); | |
1524 | return; | |
1525 | } | |
1526 | if (info->first_arg_num != 0) | |
1527 | { | |
1528 | cur_param = TREE_VALUE (params); | |
1529 | params = TREE_CHAIN (params); | |
1530 | ++arg_num; | |
0597a777 RS |
1531 | /* size_t is generally not valid here. |
1532 | It will work on most machines, because size_t and int | |
1533 | have the same mode. But might as well warn anyway, | |
1534 | since it will fail on other machines. */ | |
400fbf9f JW |
1535 | if (TREE_TYPE (cur_param) != integer_type_node) |
1536 | { | |
1537 | sprintf (message, | |
1538 | "field width is not type int (arg %d)", | |
1539 | arg_num); | |
1540 | warning (message); | |
1541 | } | |
1542 | } | |
1543 | } | |
1544 | else | |
1545 | { | |
1546 | while (ISDIGIT (*format_chars)) | |
1547 | { | |
1548 | wide = TRUE; | |
1549 | ++format_chars; | |
1550 | } | |
1551 | } | |
1552 | if (*format_chars == '.') | |
1553 | { | |
1554 | precise = TRUE; | |
1555 | /* "For d, i, o, u, x, and X conversions, | |
1556 | if a precision is specified, the 0 flag will be ignored. | |
1557 | For other conversions, the behavior is undefined." */ | |
3845b542 | 1558 | if (index (flag_chars, '0') != 0) |
400fbf9f JW |
1559 | warning ("precision and `0' flag both used in one %%-sequence"); |
1560 | ++format_chars; | |
1561 | if (*format_chars != '*' && !ISDIGIT (*format_chars)) | |
1562 | warning ("`.' not followed by `*' or digit in format"); | |
1563 | /* "...a...precision...may be indicated by an asterisk. | |
1564 | In this case, an int argument supplies the...precision." */ | |
1565 | if (*format_chars == '*') | |
1566 | { | |
1567 | if (info->first_arg_num != 0) | |
1568 | { | |
1569 | ++format_chars; | |
1570 | if (params == 0) | |
1571 | { | |
1572 | warning (tfaff); | |
1573 | return; | |
1574 | } | |
1575 | cur_param = TREE_VALUE (params); | |
1576 | params = TREE_CHAIN (params); | |
1577 | ++arg_num; | |
1578 | if (TREE_TYPE (cur_param) != integer_type_node) | |
1579 | { | |
1580 | sprintf (message, | |
1581 | "field width is not type int (arg %d)", | |
1582 | arg_num); | |
1583 | warning (message); | |
1584 | } | |
1585 | } | |
1586 | } | |
1587 | else | |
1588 | { | |
1589 | while (ISDIGIT (*format_chars)) | |
1590 | ++format_chars; | |
1591 | } | |
1592 | } | |
1593 | } | |
1594 | if (*format_chars == 'h' || *format_chars == 'l' || *format_chars == 'L') | |
1595 | length_char = *format_chars++; | |
1596 | else | |
1597 | length_char = 0; | |
1598 | if (suppressed && length_char != 0) | |
1599 | { | |
1600 | sprintf (message, | |
1601 | "use of `*' and `%c' together in format", | |
1602 | length_char); | |
1603 | warning (message); | |
1604 | } | |
1605 | format_char = *format_chars; | |
1606 | if (format_char == 0) | |
1607 | { | |
1608 | warning ("conversion lacks type at end of format"); | |
1609 | continue; | |
1610 | } | |
1611 | format_chars++; | |
1612 | fci = info->is_scan ? scan_table : print_table; | |
1613 | while (1) | |
1614 | { | |
1615 | if (fci->format_chars == 0 | |
3845b542 | 1616 | || index (fci->format_chars, format_char) != 0) |
400fbf9f JW |
1617 | break; |
1618 | ++fci; | |
1619 | } | |
1620 | if (fci->format_chars == 0) | |
1621 | { | |
1622 | if (format_char >= 040 && format_char <= 0177) | |
1623 | sprintf (message, | |
1624 | "unknown conversion type character `%c' in format", | |
1625 | format_char); | |
1626 | else | |
1627 | sprintf (message, | |
1628 | "unknown conversion type character 0x%x in format", | |
1629 | format_char); | |
1630 | warning (message); | |
1631 | continue; | |
1632 | } | |
3845b542 | 1633 | if (wide && index (fci->flag_chars, 'w') == 0) |
400fbf9f JW |
1634 | { |
1635 | sprintf (message, "width used with `%c' format", | |
1636 | format_char); | |
1637 | warning (message); | |
1638 | } | |
3845b542 | 1639 | if (precise && index (fci->flag_chars, 'p') == 0) |
400fbf9f JW |
1640 | { |
1641 | sprintf (message, "precision used with `%c' format", | |
1642 | format_char); | |
1643 | warning (message); | |
1644 | } | |
1645 | if (suppressed) | |
1646 | { | |
3845b542 | 1647 | if (index (fci->flag_chars, '*') == 0) |
400fbf9f JW |
1648 | { |
1649 | sprintf (message, | |
1650 | "suppression of `%c' conversion in format", | |
1651 | format_char); | |
1652 | warning (message); | |
1653 | } | |
1654 | continue; | |
1655 | } | |
1656 | for (i = 0; flag_chars[i] != 0; ++i) | |
1657 | { | |
3845b542 | 1658 | if (index (fci->flag_chars, flag_chars[i]) == 0) |
400fbf9f JW |
1659 | { |
1660 | sprintf (message, "flag `%c' used with type `%c'", | |
1661 | flag_chars[i], format_char); | |
1662 | warning (message); | |
1663 | } | |
1664 | } | |
1665 | switch (length_char) | |
1666 | { | |
1667 | default: wanted_type = fci->nolen ? *(fci->nolen) : 0; break; | |
1668 | case 'h': wanted_type = fci->hlen ? *(fci->hlen) : 0; break; | |
1669 | case 'l': wanted_type = fci->llen ? *(fci->llen) : 0; break; | |
1670 | case 'L': wanted_type = fci->bigllen ? *(fci->bigllen) : 0; break; | |
1671 | } | |
1672 | if (wanted_type == 0) | |
1673 | { | |
1674 | sprintf (message, | |
1675 | "use of `%c' length character with `%c' type character", | |
1676 | length_char, format_char); | |
1677 | warning (message); | |
1678 | } | |
1679 | ||
1680 | /* | |
1681 | ** XXX -- should kvetch about stuff such as | |
1682 | ** { | |
1683 | ** const int i; | |
1684 | ** | |
1685 | ** scanf ("%d", &i); | |
1686 | ** } | |
1687 | */ | |
1688 | ||
1689 | /* Finally. . .check type of argument against desired type! */ | |
1690 | if (info->first_arg_num == 0) | |
1691 | continue; | |
1692 | if (params == 0) | |
1693 | { | |
1694 | warning (tfaff); | |
1695 | return; | |
1696 | } | |
1697 | cur_param = TREE_VALUE (params); | |
1698 | params = TREE_CHAIN (params); | |
1699 | ++arg_num; | |
1700 | cur_type = TREE_TYPE (cur_param); | |
1701 | ||
1702 | /* Check the types of any additional pointer arguments | |
1703 | that precede the "real" argument. */ | |
1704 | for (i = 0; i < fci->pointer_count; ++i) | |
1705 | { | |
1706 | if (TREE_CODE (cur_type) == POINTER_TYPE) | |
1707 | { | |
1708 | cur_type = TREE_TYPE (cur_type); | |
1709 | continue; | |
1710 | } | |
1711 | sprintf (message, | |
1712 | "format argument is not a %s (arg %d)", | |
1713 | ((fci->pointer_count == 1) ? "pointer" : "pointer to a pointer"), | |
1714 | arg_num); | |
1715 | warning (message); | |
1716 | break; | |
1717 | } | |
1718 | ||
1719 | /* Check the type of the "real" argument, if there's a type we want. */ | |
1720 | if (i == fci->pointer_count && wanted_type != 0 | |
1721 | && wanted_type != cur_type | |
047de90b RS |
1722 | /* If we want `void *', allow any pointer type. |
1723 | (Anything else would already have got a warning.) */ | |
1724 | && ! (wanted_type == void_type_node | |
1725 | && fci->pointer_count > 0) | |
400fbf9f JW |
1726 | /* Don't warn about differences merely in signedness. */ |
1727 | && !(TREE_CODE (wanted_type) == INTEGER_TYPE | |
1728 | && TREE_CODE (cur_type) == INTEGER_TYPE | |
1729 | && TYPE_PRECISION (wanted_type) == TYPE_PRECISION (cur_type))) | |
1730 | { | |
1731 | register char *this; | |
1732 | register char *that; | |
1733 | ||
1734 | this = IDENTIFIER_POINTER (DECL_NAME (TYPE_NAME (wanted_type))); | |
1735 | that = 0; | |
047de90b RS |
1736 | if (TYPE_NAME (cur_type) != 0 |
1737 | && TREE_CODE (cur_type) != INTEGER_TYPE | |
1738 | && !(TREE_CODE (cur_type) == POINTER_TYPE | |
1739 | && TREE_CODE (TREE_TYPE (cur_type)) == INTEGER_TYPE) | |
1740 | && DECL_NAME (TYPE_NAME (cur_type)) != 0) | |
1741 | that = IDENTIFIER_POINTER (DECL_NAME (TYPE_NAME (cur_type))); | |
400fbf9f JW |
1742 | |
1743 | /* A nameless type can't possibly match what the format wants. | |
1744 | So there will be a warning for it. | |
1745 | Make up a string to describe vaguely what it is. */ | |
1746 | if (that == 0) | |
1747 | { | |
1748 | if (TREE_CODE (cur_type) == POINTER_TYPE) | |
1749 | that = "pointer"; | |
1750 | else | |
1751 | that = "different type"; | |
1752 | } | |
1753 | ||
1754 | if (strcmp (this, that) != 0) | |
1755 | { | |
1756 | sprintf (message, "%s format, %s arg (arg %d)", | |
1757 | this, that, arg_num); | |
1758 | warning (message); | |
1759 | } | |
1760 | } | |
1761 | } | |
1762 | } | |
1763 | \f | |
1764 | /* Build a function call to function FUNCTION with parameters PARAMS. | |
1765 | PARAMS is a list--a chain of TREE_LIST nodes--in which the | |
1766 | TREE_VALUE of each node is a parameter-expression. | |
1767 | FUNCTION's data type may be a function type or a pointer-to-function. */ | |
1768 | ||
1769 | tree | |
1770 | build_function_call (function, params) | |
1771 | tree function, params; | |
1772 | { | |
1773 | register tree fntype; | |
1774 | register tree coerced_params; | |
1775 | tree name = NULL_TREE; | |
1776 | ||
1777 | /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */ | |
1778 | if (TREE_CODE (function) == NON_LVALUE_EXPR) | |
1779 | function = TREE_OPERAND (function, 0); | |
1780 | ||
1781 | /* Convert anything with function type to a pointer-to-function. */ | |
1782 | if (TREE_CODE (function) == FUNCTION_DECL) | |
1783 | { | |
1784 | name = DECL_NAME (function); | |
1785 | /* Differs from default_conversion by not setting TREE_ADDRESSABLE | |
1786 | (because calling an inline function does not mean the function | |
1787 | needs to be separately compiled). */ | |
1788 | fntype = build_type_variant (TREE_TYPE (function), | |
1789 | TREE_READONLY (function), | |
1790 | TREE_THIS_VOLATILE (function)); | |
1791 | function = build1 (ADDR_EXPR, build_pointer_type (fntype), function); | |
1792 | } | |
1793 | else | |
1794 | function = default_conversion (function); | |
1795 | ||
1796 | fntype = TREE_TYPE (function); | |
1797 | ||
1798 | if (TREE_CODE (fntype) == ERROR_MARK) | |
1799 | return error_mark_node; | |
1800 | ||
1801 | if (!(TREE_CODE (fntype) == POINTER_TYPE | |
1802 | && TREE_CODE (TREE_TYPE (fntype)) == FUNCTION_TYPE)) | |
1803 | { | |
1804 | error ("called object is not a function"); | |
1805 | return error_mark_node; | |
1806 | } | |
1807 | ||
1808 | /* fntype now gets the type of function pointed to. */ | |
1809 | fntype = TREE_TYPE (fntype); | |
1810 | ||
1811 | /* Convert the parameters to the types declared in the | |
1812 | function prototype, or apply default promotions. */ | |
1813 | ||
1814 | coerced_params | |
1815 | = convert_arguments (TYPE_ARG_TYPES (fntype), params, name); | |
1816 | ||
1817 | /* Check for errors in format strings. */ | |
1818 | if (warn_format && name != 0) | |
1819 | { | |
1820 | unsigned int i; | |
1821 | ||
1822 | /* See if this function is a format function. */ | |
1823 | for (i = 0; i < function_info_entries; i++) | |
1824 | if (function_info_table[i].function_ident == name) | |
1825 | { | |
1826 | register char *message; | |
1827 | ||
1828 | /* If so, check it. */ | |
1829 | check_format (&function_info_table[i], coerced_params); | |
1830 | break; | |
1831 | } | |
1832 | } | |
1833 | ||
1834 | /* Recognize certain built-in functions so we can make tree-codes | |
1835 | other than CALL_EXPR. We do this when it enables fold-const.c | |
1836 | to do something useful. */ | |
1837 | ||
1838 | if (TREE_CODE (function) == ADDR_EXPR | |
1839 | && TREE_CODE (TREE_OPERAND (function, 0)) == FUNCTION_DECL | |
1840 | && DECL_BUILT_IN (TREE_OPERAND (function, 0))) | |
1841 | switch (DECL_FUNCTION_CODE (TREE_OPERAND (function, 0))) | |
1842 | { | |
1843 | case BUILT_IN_ABS: | |
1844 | case BUILT_IN_LABS: | |
1845 | case BUILT_IN_FABS: | |
1846 | if (coerced_params == 0) | |
1847 | return integer_zero_node; | |
1848 | return build_unary_op (ABS_EXPR, TREE_VALUE (coerced_params), 0); | |
1849 | } | |
1850 | ||
1851 | { | |
1852 | register tree result | |
1853 | = build (CALL_EXPR, TREE_TYPE (fntype), | |
1854 | function, coerced_params, NULL_TREE); | |
1855 | ||
1856 | TREE_SIDE_EFFECTS (result) = 1; | |
1857 | if (TREE_TYPE (result) == void_type_node) | |
1858 | return result; | |
1859 | return require_complete_type (result); | |
1860 | } | |
1861 | } | |
1862 | \f | |
1863 | /* Convert the argument expressions in the list VALUES | |
1864 | to the types in the list TYPELIST. The result is a list of converted | |
1865 | argument expressions. | |
1866 | ||
1867 | If TYPELIST is exhausted, or when an element has NULL as its type, | |
1868 | perform the default conversions. | |
1869 | ||
1870 | PARMLIST is the chain of parm decls for the function being called. | |
1871 | It may be 0, if that info is not available. | |
1872 | It is used only for generating error messages. | |
1873 | ||
1874 | NAME is an IDENTIFIER_NODE or 0. It is used only for error messages. | |
1875 | ||
1876 | This is also where warnings about wrong number of args are generated. | |
1877 | ||
1878 | Both VALUES and the returned value are chains of TREE_LIST nodes | |
1879 | with the elements of the list in the TREE_VALUE slots of those nodes. */ | |
1880 | ||
1881 | static tree | |
1882 | convert_arguments (typelist, values, name) | |
1883 | tree typelist, values, name; | |
1884 | { | |
1885 | register tree typetail, valtail; | |
1886 | register tree result = NULL; | |
1887 | int parmnum; | |
1888 | ||
1889 | /* Scan the given expressions and types, producing individual | |
1890 | converted arguments and pushing them on RESULT in reverse order. */ | |
1891 | ||
1892 | for (valtail = values, typetail = typelist, parmnum = 0; | |
1893 | valtail; | |
1894 | valtail = TREE_CHAIN (valtail), parmnum++) | |
1895 | { | |
1896 | register tree type = typetail ? TREE_VALUE (typetail) : 0; | |
1897 | register tree val = TREE_VALUE (valtail); | |
1898 | ||
1899 | if (type == void_type_node) | |
1900 | { | |
1901 | if (name) | |
1902 | error ("too many arguments to function `%s'", | |
1903 | IDENTIFIER_POINTER (name)); | |
1904 | else | |
1905 | error ("too many arguments to function"); | |
1906 | break; | |
1907 | } | |
1908 | ||
1909 | /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */ | |
1910 | if (TREE_CODE (val) == NON_LVALUE_EXPR) | |
1911 | val = TREE_OPERAND (val, 0); | |
1912 | ||
1913 | if (TREE_CODE (TREE_TYPE (val)) == ARRAY_TYPE | |
1914 | || TREE_CODE (TREE_TYPE (val)) == FUNCTION_TYPE) | |
1915 | val = default_conversion (val); | |
1916 | ||
1917 | val = require_complete_type (val); | |
1918 | ||
1919 | if (type != 0) | |
1920 | { | |
1921 | /* Formal parm type is specified by a function prototype. */ | |
1922 | tree parmval; | |
1923 | ||
1924 | if (TYPE_SIZE (type) == 0) | |
1925 | { | |
1926 | error ("type of formal parameter %d is incomplete", parmnum + 1); | |
1927 | parmval = val; | |
1928 | } | |
1929 | else | |
1930 | { | |
1931 | tree parmname; | |
1932 | #ifdef PROMOTE_PROTOTYPES | |
1933 | /* Rather than truncating and then reextending, | |
1934 | convert directly to int, if that's the type we will want. */ | |
1935 | if (! flag_traditional | |
1936 | && TREE_CODE (type) == INTEGER_TYPE | |
1937 | && (TYPE_PRECISION (type) < TYPE_PRECISION (integer_type_node))) | |
1938 | type = integer_type_node; | |
1939 | #endif | |
1940 | ||
1941 | #if 0 /* This turns out not to win--there's no way to write a prototype | |
1942 | for a function whose arg type is a union with no tag. */ | |
1943 | /* Nameless union automatically casts the types it contains. */ | |
1944 | if (TREE_CODE (type) == UNION_TYPE && TYPE_NAME (type) == 0) | |
1945 | { | |
1946 | tree field; | |
1947 | ||
1948 | for (field = TYPE_FIELDS (type); field; | |
1949 | field = TREE_CHAIN (field)) | |
1950 | if (comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (field)), | |
1951 | TYPE_MAIN_VARIANT (TREE_TYPE (val)))) | |
1952 | break; | |
1953 | ||
1954 | if (field) | |
1955 | val = build1 (CONVERT_EXPR, type, val); | |
1956 | } | |
1957 | #endif | |
1958 | ||
d45cf215 RS |
1959 | /* Optionally warn about conversions that |
1960 | differ from the default conversions. */ | |
400fbf9f JW |
1961 | if (warn_conversion) |
1962 | { | |
1963 | int formal_prec = TYPE_PRECISION (type); | |
400fbf9f JW |
1964 | |
1965 | if (TREE_CODE (type) != REAL_TYPE | |
1966 | && TREE_CODE (TREE_TYPE (val)) == REAL_TYPE) | |
754a4d82 | 1967 | warn_for_assignment ("%s as integer rather than floating due to prototype", (char *) 0, name, parmnum + 1); |
400fbf9f JW |
1968 | else if (TREE_CODE (type) == REAL_TYPE |
1969 | && TREE_CODE (TREE_TYPE (val)) != REAL_TYPE) | |
754a4d82 | 1970 | warn_for_assignment ("%s as floating rather than integer due to prototype", (char *) 0, name, parmnum + 1); |
d45cf215 RS |
1971 | else if (TREE_CODE (type) == REAL_TYPE |
1972 | && TREE_CODE (TREE_TYPE (val)) == REAL_TYPE) | |
1973 | { | |
1974 | /* Warn if any argument is passed as `float', | |
047de90b | 1975 | since without a prototype it would be `double'. */ |
d45cf215 | 1976 | if (formal_prec == TYPE_PRECISION (float_type_node)) |
754a4d82 | 1977 | warn_for_assignment ("%s as `float' rather than `double' due to prototype", (char *) 0, name, parmnum + 1); |
d45cf215 | 1978 | } |
400fbf9f JW |
1979 | /* Detect integer changing in width or signedness. */ |
1980 | else if ((TREE_CODE (type) == INTEGER_TYPE | |
1981 | || TREE_CODE (type) == ENUMERAL_TYPE) | |
1982 | && (TREE_CODE (TREE_TYPE (val)) == INTEGER_TYPE | |
d45cf215 | 1983 | || TREE_CODE (TREE_TYPE (val)) == ENUMERAL_TYPE)) |
400fbf9f | 1984 | { |
d45cf215 RS |
1985 | tree would_have_been = default_conversion (val); |
1986 | tree type1 = TREE_TYPE (would_have_been); | |
1987 | ||
754a4d82 RS |
1988 | if (TREE_CODE (type) == ENUMERAL_TYPE |
1989 | && type == TREE_TYPE (val)) | |
1990 | /* No warning if function asks for enum | |
1991 | and the actual arg is that enum type. */ | |
1992 | ; | |
1993 | else if (formal_prec != TYPE_PRECISION (type1)) | |
1994 | warn_for_assignment ("%s with different width due to prototype", (char *) 0, name, parmnum + 1); | |
d45cf215 RS |
1995 | else if (TREE_UNSIGNED (type) == TREE_UNSIGNED (type1)) |
1996 | ; | |
800cd3b9 RS |
1997 | /* Don't complain if the formal parameter type |
1998 | is an enum, because we can't tell now whether | |
1999 | the value was an enum--even the same enum. */ | |
2000 | else if (TREE_CODE (type) == ENUMERAL_TYPE) | |
2001 | ; | |
400fbf9f JW |
2002 | else if (TREE_CODE (val) == INTEGER_CST |
2003 | && int_fits_type_p (val, type)) | |
2004 | /* Change in signedness doesn't matter | |
2005 | if a constant value is unaffected. */ | |
2006 | ; | |
047de90b RS |
2007 | else if (TREE_CODE (TREE_TYPE (val)) == ENUMERAL_TYPE |
2008 | && int_fits_type_p (TYPE_MIN_VALUE (TREE_TYPE (val)), type) | |
2009 | && int_fits_type_p (TYPE_MAX_VALUE (TREE_TYPE (val)), type)) | |
2010 | /* Change in signedness doesn't matter | |
2011 | if an enum value is unaffected. */ | |
2012 | ; | |
400fbf9f | 2013 | else if (TREE_UNSIGNED (type)) |
754a4d82 | 2014 | warn_for_assignment ("%s as unsigned due to prototype", (char *) 0, name, parmnum + 1); |
400fbf9f | 2015 | else |
754a4d82 | 2016 | warn_for_assignment ("%s as signed due to prototype", (char *) 0, name, parmnum + 1); |
400fbf9f JW |
2017 | } |
2018 | } | |
2019 | ||
2020 | parmval = convert_for_assignment (type, val, | |
2021 | (char *)0, /* arg passing */ | |
2022 | name, parmnum + 1); | |
2023 | ||
2024 | #ifdef PROMOTE_PROTOTYPES | |
2025 | if (TREE_CODE (type) == INTEGER_TYPE | |
2026 | && (TYPE_PRECISION (type) < TYPE_PRECISION (integer_type_node))) | |
2027 | parmval = default_conversion (parmval); | |
2028 | #endif | |
2029 | } | |
2030 | result = tree_cons (0, parmval, result); | |
2031 | } | |
2032 | else if (TREE_CODE (TREE_TYPE (val)) == REAL_TYPE | |
2033 | && (TYPE_PRECISION (TREE_TYPE (val)) | |
2034 | < TYPE_PRECISION (double_type_node))) | |
2035 | /* Convert `float' to `double'. */ | |
2036 | result = tree_cons (NULL_TREE, convert (double_type_node, val), result); | |
2037 | else | |
2038 | /* Convert `short' and `char' to full-size `int'. */ | |
2039 | result = tree_cons (NULL_TREE, default_conversion (val), result); | |
2040 | ||
2041 | if (typetail) | |
2042 | typetail = TREE_CHAIN (typetail); | |
2043 | } | |
2044 | ||
2045 | if (typetail != 0 && TREE_VALUE (typetail) != void_type_node) | |
2046 | { | |
2047 | if (name) | |
2048 | error ("too few arguments to function `%s'", | |
2049 | IDENTIFIER_POINTER (name)); | |
2050 | else | |
2051 | error ("too few arguments to function"); | |
2052 | } | |
2053 | ||
2054 | return nreverse (result); | |
2055 | } | |
2056 | \f | |
2057 | /* This is the entry point used by the parser | |
2058 | for binary operators in the input. | |
2059 | In addition to constructing the expression, | |
2060 | we check for operands that were written with other binary operators | |
2061 | in a way that is likely to confuse the user. */ | |
2062 | ||
2063 | tree | |
2064 | parser_build_binary_op (code, arg1, arg2) | |
2065 | enum tree_code code; | |
2066 | tree arg1, arg2; | |
2067 | { | |
2068 | tree result = build_binary_op (code, arg1, arg2, 1); | |
2069 | ||
2070 | char class; | |
2071 | char class1 = TREE_CODE_CLASS (TREE_CODE (arg1)); | |
2072 | char class2 = TREE_CODE_CLASS (TREE_CODE (arg2)); | |
2073 | enum tree_code code1 = ERROR_MARK; | |
2074 | enum tree_code code2 = ERROR_MARK; | |
2075 | ||
2076 | if (class1 == 'e' || class1 == '1' | |
2077 | || class1 == '2' || class1 == '<') | |
2078 | code1 = C_EXP_ORIGINAL_CODE (arg1); | |
2079 | if (class2 == 'e' || class2 == '1' | |
2080 | || class2 == '2' || class2 == '<') | |
2081 | code2 = C_EXP_ORIGINAL_CODE (arg2); | |
2082 | ||
2083 | /* Check for cases such as x+y<<z which users are likely | |
2084 | to misinterpret. If parens are used, C_EXP_ORIGINAL_CODE | |
2085 | is cleared to prevent these warnings. */ | |
2086 | if (warn_parentheses) | |
2087 | { | |
2088 | if (code == LSHIFT_EXPR || code == RSHIFT_EXPR) | |
2089 | { | |
2090 | if (code1 == PLUS_EXPR || code1 == MINUS_EXPR | |
2091 | || code2 == PLUS_EXPR || code2 == MINUS_EXPR) | |
2092 | warning ("suggest parentheses around + or - inside shift"); | |
2093 | } | |
2094 | ||
2095 | if (code == TRUTH_ORIF_EXPR) | |
2096 | { | |
2097 | if (code1 == TRUTH_ANDIF_EXPR | |
2098 | || code2 == TRUTH_ANDIF_EXPR) | |
2099 | warning ("suggest parentheses around && within ||"); | |
2100 | } | |
2101 | ||
2102 | if (code == BIT_IOR_EXPR) | |
2103 | { | |
2104 | if (code1 == BIT_AND_EXPR || code1 == BIT_XOR_EXPR | |
2105 | || code1 == PLUS_EXPR || code1 == MINUS_EXPR | |
2106 | || code2 == BIT_AND_EXPR || code2 == BIT_XOR_EXPR | |
2107 | || code2 == PLUS_EXPR || code2 == MINUS_EXPR) | |
2108 | warning ("suggest parentheses around arithmetic in operand of |"); | |
2109 | } | |
2110 | ||
2111 | if (code == BIT_XOR_EXPR) | |
2112 | { | |
2113 | if (code1 == BIT_AND_EXPR | |
2114 | || code1 == PLUS_EXPR || code1 == MINUS_EXPR | |
2115 | || code2 == BIT_AND_EXPR | |
2116 | || code2 == PLUS_EXPR || code2 == MINUS_EXPR) | |
2117 | warning ("suggest parentheses around arithmetic in operand of ^"); | |
2118 | } | |
2119 | ||
2120 | if (code == BIT_AND_EXPR) | |
2121 | { | |
2122 | if (code1 == PLUS_EXPR || code1 == MINUS_EXPR | |
2123 | || code2 == PLUS_EXPR || code2 == MINUS_EXPR) | |
2124 | warning ("suggest parentheses around + or - in operand of &"); | |
2125 | } | |
2126 | } | |
2127 | ||
2128 | class = TREE_CODE_CLASS (TREE_CODE (result)); | |
2129 | ||
2130 | /* Record the code that was specified in the source, | |
2131 | for the sake of warnings about confusing nesting. */ | |
2132 | if (class == 'e' || class == '1' | |
2133 | || class == '2' || class == '<') | |
2134 | C_SET_EXP_ORIGINAL_CODE (result, code); | |
2135 | else | |
2136 | { | |
2137 | int flag = TREE_CONSTANT (result); | |
2138 | result = build1 (NON_LVALUE_EXPR, TREE_TYPE (result), result); | |
2139 | C_SET_EXP_ORIGINAL_CODE (result, code); | |
2140 | TREE_CONSTANT (result) = flag; | |
2141 | } | |
2142 | ||
2143 | return result; | |
2144 | } | |
2145 | ||
2146 | /* Build a binary-operation expression without default conversions. | |
2147 | CODE is the kind of expression to build. | |
2148 | This function differs from `build' in several ways: | |
2149 | the data type of the result is computed and recorded in it, | |
2150 | warnings are generated if arg data types are invalid, | |
2151 | special handling for addition and subtraction of pointers is known, | |
2152 | and some optimization is done (operations on narrow ints | |
2153 | are done in the narrower type when that gives the same result). | |
2154 | Constant folding is also done before the result is returned. | |
2155 | ||
2156 | Note that the operands will never have enumeral types, or function | |
2157 | or array types, because either they will have the default conversions | |
2158 | performed or they have both just been converted to some other type in which | |
2159 | the arithmetic is to be done. */ | |
2160 | ||
2161 | tree | |
2162 | build_binary_op (code, orig_op0, orig_op1, convert_p) | |
2163 | enum tree_code code; | |
2164 | tree orig_op0, orig_op1; | |
2165 | int convert_p; | |
2166 | { | |
2167 | tree type0, type1; | |
2168 | register enum tree_code code0, code1; | |
2169 | tree op0, op1; | |
2170 | ||
2171 | /* Expression code to give to the expression when it is built. | |
2172 | Normally this is CODE, which is what the caller asked for, | |
2173 | but in some special cases we change it. */ | |
2174 | register enum tree_code resultcode = code; | |
2175 | ||
2176 | /* Data type in which the computation is to be performed. | |
2177 | In the simplest cases this is the common type of the arguments. */ | |
2178 | register tree result_type = NULL; | |
2179 | ||
2180 | /* Nonzero means operands have already been type-converted | |
2181 | in whatever way is necessary. | |
2182 | Zero means they need to be converted to RESULT_TYPE. */ | |
2183 | int converted = 0; | |
2184 | ||
2185 | /* Nonzero means after finally constructing the expression | |
2186 | give it this type. Otherwise, give it type RESULT_TYPE. */ | |
2187 | tree final_type = 0; | |
2188 | ||
2189 | /* Nonzero if this is an operation like MIN or MAX which can | |
2190 | safely be computed in short if both args are promoted shorts. | |
2191 | Also implies COMMON. | |
2192 | -1 indicates a bitwise operation; this makes a difference | |
2193 | in the exact conditions for when it is safe to do the operation | |
2194 | in a narrower mode. */ | |
2195 | int shorten = 0; | |
2196 | ||
2197 | /* Nonzero if this is a comparison operation; | |
2198 | if both args are promoted shorts, compare the original shorts. | |
2199 | Also implies COMMON. */ | |
2200 | int short_compare = 0; | |
2201 | ||
2202 | /* Nonzero if this is a right-shift operation, which can be computed on the | |
2203 | original short and then promoted if the operand is a promoted short. */ | |
2204 | int short_shift = 0; | |
2205 | ||
2206 | /* Nonzero means set RESULT_TYPE to the common type of the args. */ | |
2207 | int common = 0; | |
2208 | ||
2209 | if (convert_p) | |
2210 | { | |
2211 | op0 = default_conversion (orig_op0); | |
2212 | op1 = default_conversion (orig_op1); | |
2213 | } | |
2214 | else | |
2215 | { | |
2216 | op0 = orig_op0; | |
2217 | op1 = orig_op1; | |
2218 | } | |
2219 | ||
2220 | type0 = TREE_TYPE (op0); | |
2221 | type1 = TREE_TYPE (op1); | |
2222 | ||
2223 | /* The expression codes of the data types of the arguments tell us | |
2224 | whether the arguments are integers, floating, pointers, etc. */ | |
2225 | code0 = TREE_CODE (type0); | |
2226 | code1 = TREE_CODE (type1); | |
2227 | ||
2228 | /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */ | |
2229 | if (TREE_CODE (op0) == NON_LVALUE_EXPR) | |
2230 | op0 = TREE_OPERAND (op0, 0); | |
2231 | if (TREE_CODE (op1) == NON_LVALUE_EXPR) | |
2232 | op1 = TREE_OPERAND (op1, 0); | |
2233 | ||
2234 | /* If an error was already reported for one of the arguments, | |
2235 | avoid reporting another error. */ | |
2236 | ||
2237 | if (code0 == ERROR_MARK || code1 == ERROR_MARK) | |
2238 | return error_mark_node; | |
2239 | ||
2240 | switch (code) | |
2241 | { | |
2242 | case PLUS_EXPR: | |
2243 | /* Handle the pointer + int case. */ | |
2244 | if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE) | |
2245 | return pointer_int_sum (PLUS_EXPR, op0, op1); | |
2246 | else if (code1 == POINTER_TYPE && code0 == INTEGER_TYPE) | |
2247 | return pointer_int_sum (PLUS_EXPR, op1, op0); | |
2248 | else | |
2249 | common = 1; | |
2250 | break; | |
2251 | ||
2252 | case MINUS_EXPR: | |
2253 | /* Subtraction of two similar pointers. | |
2254 | We must subtract them as integers, then divide by object size. */ | |
2255 | if (code0 == POINTER_TYPE && code1 == POINTER_TYPE | |
2256 | && comp_target_types (type0, type1)) | |
2257 | return pointer_diff (op0, op1); | |
2258 | /* Handle pointer minus int. Just like pointer plus int. */ | |
2259 | else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE) | |
2260 | return pointer_int_sum (MINUS_EXPR, op0, op1); | |
2261 | else | |
2262 | common = 1; | |
2263 | break; | |
2264 | ||
2265 | case MULT_EXPR: | |
2266 | common = 1; | |
2267 | break; | |
2268 | ||
2269 | case TRUNC_DIV_EXPR: | |
2270 | case CEIL_DIV_EXPR: | |
2271 | case FLOOR_DIV_EXPR: | |
2272 | case ROUND_DIV_EXPR: | |
2273 | case EXACT_DIV_EXPR: | |
2274 | if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE) | |
2275 | && (code1 == INTEGER_TYPE || code1 == REAL_TYPE)) | |
2276 | { | |
2277 | if (!(code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)) | |
2278 | resultcode = RDIV_EXPR; | |
2279 | else | |
2280 | shorten = 1; | |
2281 | common = 1; | |
2282 | } | |
2283 | break; | |
2284 | ||
2285 | case BIT_AND_EXPR: | |
2286 | case BIT_ANDTC_EXPR: | |
2287 | case BIT_IOR_EXPR: | |
2288 | case BIT_XOR_EXPR: | |
2289 | if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE) | |
2290 | shorten = -1; | |
2291 | /* If one operand is a constant, and the other is a short type | |
2292 | that has been converted to an int, | |
2293 | really do the work in the short type and then convert the | |
2294 | result to int. If we are lucky, the constant will be 0 or 1 | |
2295 | in the short type, making the entire operation go away. */ | |
2296 | if (TREE_CODE (op0) == INTEGER_CST | |
2297 | && TREE_CODE (op1) == NOP_EXPR | |
2298 | && TYPE_PRECISION (type1) > TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (op1, 0))) | |
2299 | && TREE_UNSIGNED (TREE_TYPE (TREE_OPERAND (op1, 0)))) | |
2300 | { | |
2301 | final_type = result_type; | |
2302 | op1 = TREE_OPERAND (op1, 0); | |
2303 | result_type = TREE_TYPE (op1); | |
2304 | } | |
2305 | if (TREE_CODE (op1) == INTEGER_CST | |
2306 | && TREE_CODE (op0) == NOP_EXPR | |
2307 | && TYPE_PRECISION (type0) > TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (op0, 0))) | |
2308 | && TREE_UNSIGNED (TREE_TYPE (TREE_OPERAND (op0, 0)))) | |
2309 | { | |
2310 | final_type = result_type; | |
2311 | op0 = TREE_OPERAND (op0, 0); | |
2312 | result_type = TREE_TYPE (op0); | |
2313 | } | |
2314 | break; | |
2315 | ||
2316 | case TRUNC_MOD_EXPR: | |
047de90b | 2317 | case FLOOR_MOD_EXPR: |
400fbf9f JW |
2318 | if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE) |
2319 | shorten = 1; | |
2320 | break; | |
2321 | ||
2322 | case TRUTH_ANDIF_EXPR: | |
2323 | case TRUTH_ORIF_EXPR: | |
2324 | case TRUTH_AND_EXPR: | |
2325 | case TRUTH_OR_EXPR: | |
2326 | if ((code0 == INTEGER_TYPE || code0 == POINTER_TYPE || code0 == REAL_TYPE) | |
2327 | && (code1 == INTEGER_TYPE || code1 == POINTER_TYPE || code1 == REAL_TYPE)) | |
2328 | { | |
2329 | /* Result of these operations is always an int, | |
2330 | but that does not mean the operands should be | |
2331 | converted to ints! */ | |
2332 | result_type = integer_type_node; | |
2333 | op0 = truthvalue_conversion (op0); | |
2334 | op1 = truthvalue_conversion (op1); | |
2335 | converted = 1; | |
2336 | } | |
2337 | break; | |
2338 | ||
2339 | /* Shift operations: result has same type as first operand; | |
2340 | always convert second operand to int. | |
2341 | Also set SHORT_SHIFT if shifting rightward. */ | |
2342 | ||
2343 | case RSHIFT_EXPR: | |
2344 | if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE) | |
2345 | { | |
2346 | if (TREE_CODE (op1) == INTEGER_CST) | |
2347 | { | |
2348 | if (TREE_INT_CST_LOW (op1) > 0) | |
2349 | short_shift = 1; | |
2350 | else if (TREE_INT_CST_LOW (op1) < 0) | |
2351 | warning ("shift count is negative"); | |
2352 | if (TREE_INT_CST_LOW (op1) >= TYPE_PRECISION (type0)) | |
2353 | warning ("shift count exceeds width of value shifted"); | |
2354 | } | |
d45cf215 RS |
2355 | /* Use the type of the value to be shifted. |
2356 | This is what most traditional C compilers do. */ | |
2357 | result_type = type0; | |
400fbf9f JW |
2358 | /* Unless traditional, convert the shift-count to an integer, |
2359 | regardless of size of value being shifted. */ | |
2360 | if (! flag_traditional) | |
2361 | { | |
400fbf9f JW |
2362 | if (TREE_TYPE (op1) != integer_type_node) |
2363 | op1 = convert (integer_type_node, op1); | |
2364 | /* Avoid converting op1 to result_type later. */ | |
2365 | converted = 1; | |
2366 | } | |
400fbf9f JW |
2367 | } |
2368 | break; | |
2369 | ||
2370 | case LSHIFT_EXPR: | |
2371 | if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE) | |
2372 | { | |
2373 | if (TREE_CODE (op1) == INTEGER_CST | |
2374 | && TREE_INT_CST_LOW (op1) < 0) | |
2375 | warning ("shift count is negative"); | |
2376 | if (TREE_CODE (op1) == INTEGER_CST | |
2377 | && TREE_INT_CST_LOW (op1) >= TYPE_PRECISION (type0)) | |
2378 | warning ("shift count exceeds width of value shifted"); | |
d45cf215 RS |
2379 | /* Use the type of the value to be shifted. |
2380 | This is what most traditional C compilers do. */ | |
2381 | result_type = type0; | |
400fbf9f JW |
2382 | /* Unless traditional, convert the shift-count to an integer, |
2383 | regardless of size of value being shifted. */ | |
2384 | if (! flag_traditional) | |
2385 | { | |
400fbf9f JW |
2386 | if (TREE_TYPE (op1) != integer_type_node) |
2387 | op1 = convert (integer_type_node, op1); | |
2388 | /* Avoid converting op1 to result_type later. */ | |
2389 | converted = 1; | |
2390 | } | |
400fbf9f JW |
2391 | } |
2392 | break; | |
2393 | ||
2394 | case RROTATE_EXPR: | |
2395 | case LROTATE_EXPR: | |
2396 | if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE) | |
2397 | { | |
2398 | if (TREE_CODE (op1) == INTEGER_CST | |
2399 | && TREE_INT_CST_LOW (op1) < 0) | |
2400 | warning ("shift count is negative"); | |
2401 | if (TREE_CODE (op1) == INTEGER_CST | |
2402 | && TREE_INT_CST_LOW (op1) >= TYPE_PRECISION (type0)) | |
2403 | warning ("shift count >= width of value shifted"); | |
d45cf215 RS |
2404 | /* Use the type of the value to be shifted. |
2405 | This is what most traditional C compilers do. */ | |
2406 | result_type = type0; | |
400fbf9f JW |
2407 | /* Unless traditional, convert the shift-count to an integer, |
2408 | regardless of size of value being shifted. */ | |
2409 | if (! flag_traditional) | |
2410 | { | |
400fbf9f JW |
2411 | if (TREE_TYPE (op1) != integer_type_node) |
2412 | op1 = convert (integer_type_node, op1); | |
2413 | /* Avoid converting op1 to result_type later. */ | |
2414 | converted = 1; | |
2415 | } | |
400fbf9f JW |
2416 | } |
2417 | break; | |
2418 | ||
2419 | case EQ_EXPR: | |
2420 | case NE_EXPR: | |
2421 | /* Result of comparison is always int, | |
2422 | but don't convert the args to int! */ | |
2423 | result_type = integer_type_node; | |
2424 | converted = 1; | |
2425 | if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE) | |
2426 | && (code1 == INTEGER_TYPE || code1 == REAL_TYPE)) | |
2427 | short_compare = 1; | |
2428 | else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE) | |
2429 | { | |
2430 | register tree tt0 = TREE_TYPE (type0); | |
2431 | register tree tt1 = TREE_TYPE (type1); | |
2432 | /* Anything compares with void *. void * compares with anything. | |
2433 | Otherwise, the targets must be the same. */ | |
2434 | if (comp_target_types (type0, type1)) | |
2435 | ; | |
2436 | else if (TYPE_MAIN_VARIANT (tt0) == void_type_node) | |
2437 | { | |
2438 | if (pedantic && !integer_zerop (op0) | |
2439 | && TREE_CODE (tt1) == FUNCTION_TYPE) | |
2440 | pedwarn ("ANSI C forbids comparison of `void *' with function pointer"); | |
2441 | } | |
2442 | else if (TYPE_MAIN_VARIANT (tt1) == void_type_node) | |
2443 | { | |
2444 | if (pedantic && !integer_zerop (op1) | |
2445 | && TREE_CODE (tt0) == FUNCTION_TYPE) | |
2446 | pedwarn ("ANSI C forbids comparison of `void *' with function pointer"); | |
2447 | } | |
2448 | else | |
2449 | pedwarn ("comparison of distinct pointer types lacks a cast"); | |
2450 | } | |
2451 | else if (code0 == POINTER_TYPE && TREE_CODE (op1) == INTEGER_CST | |
2452 | && integer_zerop (op1)) | |
2453 | op1 = null_pointer_node; | |
2454 | else if (code1 == POINTER_TYPE && TREE_CODE (op0) == INTEGER_CST | |
2455 | && integer_zerop (op0)) | |
2456 | op0 = null_pointer_node; | |
2457 | else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE) | |
2458 | { | |
2459 | if (! flag_traditional) | |
2460 | pedwarn ("comparison between pointer and integer"); | |
2461 | op1 = convert (TREE_TYPE (op0), op1); | |
2462 | } | |
2463 | else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE) | |
2464 | { | |
2465 | if (! flag_traditional) | |
2466 | pedwarn ("comparison between pointer and integer"); | |
2467 | op0 = convert (TREE_TYPE (op1), op0); | |
2468 | } | |
2469 | else | |
2470 | /* If args are not valid, clear out RESULT_TYPE | |
2471 | to cause an error message later. */ | |
2472 | result_type = 0; | |
2473 | break; | |
2474 | ||
2475 | case MAX_EXPR: | |
2476 | case MIN_EXPR: | |
2477 | if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE) | |
2478 | && (code1 == INTEGER_TYPE || code1 == REAL_TYPE)) | |
2479 | shorten = 1; | |
2480 | else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE) | |
2481 | { | |
2482 | if (! comp_target_types (type0, type1)) | |
2483 | pedwarn ("comparison of distinct pointer types lacks a cast"); | |
2484 | else if (pedantic | |
2485 | && TREE_CODE (TREE_TYPE (type0)) == FUNCTION_TYPE) | |
2486 | pedwarn ("ANSI C forbids ordered comparisons of pointers to functions"); | |
2487 | result_type = common_type (type0, type1); | |
2488 | } | |
2489 | break; | |
2490 | ||
2491 | case LE_EXPR: | |
2492 | case GE_EXPR: | |
2493 | case LT_EXPR: | |
2494 | case GT_EXPR: | |
2495 | if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE) | |
2496 | && (code1 == INTEGER_TYPE || code1 == REAL_TYPE)) | |
2497 | short_compare = 1; | |
2498 | else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE) | |
2499 | { | |
2500 | if (! comp_target_types (type0, type1)) | |
2501 | pedwarn ("comparison of distinct pointer types lacks a cast"); | |
2502 | else if (pedantic | |
2503 | && TREE_CODE (TREE_TYPE (type0)) == FUNCTION_TYPE) | |
2504 | pedwarn ("ANSI C forbids ordered comparisons of pointers to functions"); | |
2505 | result_type = integer_type_node; | |
2506 | } | |
2507 | else if (code0 == POINTER_TYPE && TREE_CODE (op1) == INTEGER_CST | |
2508 | && integer_zerop (op1)) | |
2509 | { | |
2510 | result_type = integer_type_node; | |
2511 | op1 = null_pointer_node; | |
2512 | if (! flag_traditional) | |
2513 | pedwarn ("ordered comparison of pointer with integer zero"); | |
2514 | } | |
2515 | else if (code1 == POINTER_TYPE && TREE_CODE (op0) == INTEGER_CST | |
2516 | && integer_zerop (op0)) | |
2517 | { | |
2518 | result_type = integer_type_node; | |
2519 | op0 = null_pointer_node; | |
2520 | if (pedantic) | |
2521 | pedwarn ("ordered comparison of pointer with integer zero"); | |
2522 | } | |
2523 | else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE) | |
2524 | { | |
2525 | result_type = integer_type_node; | |
2526 | if (! flag_traditional) | |
2527 | pedwarn ("comparison between pointer and integer"); | |
2528 | op1 = convert (TREE_TYPE (op0), op1); | |
2529 | } | |
2530 | else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE) | |
2531 | { | |
2532 | result_type = integer_type_node; | |
2533 | if (! flag_traditional) | |
2534 | pedwarn ("comparison between pointer and integer"); | |
2535 | op0 = convert (TREE_TYPE (op1), op0); | |
2536 | } | |
2537 | converted = 1; | |
2538 | break; | |
2539 | } | |
2540 | ||
2541 | if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE) | |
2542 | && (code1 == INTEGER_TYPE || code1 == REAL_TYPE)) | |
2543 | { | |
2544 | if (shorten || common || short_compare) | |
2545 | result_type = common_type (type0, type1); | |
2546 | ||
2547 | /* For certain operations (which identify themselves by shorten != 0) | |
2548 | if both args were extended from the same smaller type, | |
2549 | do the arithmetic in that type and then extend. | |
2550 | ||
2551 | shorten !=0 and !=1 indicates a bitwise operation. | |
2552 | For them, this optimization is safe only if | |
2553 | both args are zero-extended or both are sign-extended. | |
2554 | Otherwise, we might change the result. | |
2555 | Eg, (short)-1 | (unsigned short)-1 is (int)-1 | |
2556 | but calculated in (unsigned short) it would be (unsigned short)-1. */ | |
2557 | ||
2558 | if (shorten) | |
2559 | { | |
2560 | int unsigned0, unsigned1; | |
2561 | tree arg0 = get_narrower (op0, &unsigned0); | |
2562 | tree arg1 = get_narrower (op1, &unsigned1); | |
2563 | /* UNS is 1 if the operation to be done is an unsigned one. */ | |
2564 | int uns = TREE_UNSIGNED (result_type); | |
2565 | tree type; | |
2566 | ||
2567 | final_type = result_type; | |
2568 | ||
e7951b3f | 2569 | /* Handle the case that OP0 (or OP1) does not *contain* a conversion |
400fbf9f JW |
2570 | but it *requires* conversion to FINAL_TYPE. */ |
2571 | ||
e7951b3f RS |
2572 | if ((TYPE_PRECISION (TREE_TYPE (op0)) |
2573 | == TYPE_PRECISION (TREE_TYPE (arg0))) | |
2574 | && TREE_TYPE (op0) != final_type) | |
400fbf9f | 2575 | unsigned0 = TREE_UNSIGNED (TREE_TYPE (op0)); |
e7951b3f RS |
2576 | if ((TYPE_PRECISION (TREE_TYPE (op1)) |
2577 | == TYPE_PRECISION (TREE_TYPE (arg1))) | |
2578 | && TREE_TYPE (op1) != final_type) | |
400fbf9f JW |
2579 | unsigned1 = TREE_UNSIGNED (TREE_TYPE (op1)); |
2580 | ||
2581 | /* Now UNSIGNED0 is 1 if ARG0 zero-extends to FINAL_TYPE. */ | |
2582 | ||
2583 | /* For bitwise operations, signedness of nominal type | |
2584 | does not matter. Consider only how operands were extended. */ | |
2585 | if (shorten == -1) | |
2586 | uns = unsigned0; | |
2587 | ||
2588 | /* Note that in all three cases below we refrain from optimizing | |
2589 | an unsigned operation on sign-extended args. | |
2590 | That would not be valid. */ | |
2591 | ||
2592 | /* Both args variable: if both extended in same way | |
2593 | from same width, do it in that width. | |
2594 | Do it unsigned if args were zero-extended. */ | |
2595 | if ((TYPE_PRECISION (TREE_TYPE (arg0)) | |
2596 | < TYPE_PRECISION (result_type)) | |
2597 | && (TYPE_PRECISION (TREE_TYPE (arg1)) | |
2598 | == TYPE_PRECISION (TREE_TYPE (arg0))) | |
2599 | && unsigned0 == unsigned1 | |
2600 | && (unsigned0 || !uns)) | |
2601 | result_type | |
2602 | = signed_or_unsigned_type (unsigned0, | |
2603 | common_type (TREE_TYPE (arg0), TREE_TYPE (arg1))); | |
2604 | else if (TREE_CODE (arg0) == INTEGER_CST | |
2605 | && (unsigned1 || !uns) | |
2606 | && (TYPE_PRECISION (TREE_TYPE (arg1)) | |
2607 | < TYPE_PRECISION (result_type)) | |
2608 | && (type = signed_or_unsigned_type (unsigned1, | |
2609 | TREE_TYPE (arg1)), | |
2610 | int_fits_type_p (arg0, type))) | |
2611 | result_type = type; | |
2612 | else if (TREE_CODE (arg1) == INTEGER_CST | |
2613 | && (unsigned0 || !uns) | |
2614 | && (TYPE_PRECISION (TREE_TYPE (arg0)) | |
2615 | < TYPE_PRECISION (result_type)) | |
2616 | && (type = signed_or_unsigned_type (unsigned0, | |
2617 | TREE_TYPE (arg0)), | |
2618 | int_fits_type_p (arg1, type))) | |
2619 | result_type = type; | |
2620 | } | |
2621 | ||
2622 | /* Shifts can be shortened if shifting right. */ | |
2623 | ||
2624 | if (short_shift) | |
2625 | { | |
2626 | int unsigned_arg; | |
2627 | tree arg0 = get_narrower (op0, &unsigned_arg); | |
2628 | ||
2629 | final_type = result_type; | |
2630 | ||
2631 | if (arg0 == op0 && final_type == TREE_TYPE (op0)) | |
2632 | unsigned_arg = TREE_UNSIGNED (TREE_TYPE (op0)); | |
2633 | ||
2634 | if (TYPE_PRECISION (TREE_TYPE (arg0)) < TYPE_PRECISION (result_type) | |
2635 | /* If arg is sign-extended and then unsigned-shifted, | |
2636 | we can simulate this with a signed shift in arg's type | |
2637 | only if the extended result is at least twice as wide | |
2638 | as the arg. Otherwise, the shift could use up all the | |
2639 | ones made by sign-extension and bring in zeros. | |
2640 | We can't optimize that case at all, but in most machines | |
2641 | it never happens because available widths are 2**N. */ | |
2642 | && (!TREE_UNSIGNED (final_type) | |
2643 | || unsigned_arg | |
2644 | || 2 * TYPE_PRECISION (TREE_TYPE (arg0)) <= TYPE_PRECISION (result_type))) | |
2645 | { | |
2646 | /* Do an unsigned shift if the operand was zero-extended. */ | |
2647 | result_type | |
2648 | = signed_or_unsigned_type (unsigned_arg, | |
2649 | TREE_TYPE (arg0)); | |
2650 | /* Convert value-to-be-shifted to that type. */ | |
2651 | if (TREE_TYPE (op0) != result_type) | |
2652 | op0 = convert (result_type, op0); | |
2653 | converted = 1; | |
2654 | } | |
2655 | } | |
2656 | ||
2657 | /* Comparison operations are shortened too but differently. | |
2658 | They identify themselves by setting short_compare = 1. */ | |
2659 | ||
2660 | if (short_compare) | |
2661 | { | |
2662 | /* Don't write &op0, etc., because that would prevent op0 | |
2663 | from being kept in a register. | |
2664 | Instead, make copies of the our local variables and | |
2665 | pass the copies by reference, then copy them back afterward. */ | |
2666 | tree xop0 = op0, xop1 = op1, xresult_type = result_type; | |
2667 | enum tree_code xresultcode = resultcode; | |
2668 | tree val | |
2669 | = shorten_compare (&xop0, &xop1, &xresult_type, &xresultcode); | |
2670 | if (val != 0) | |
2671 | return val; | |
2672 | op0 = xop0, op1 = xop1, result_type = xresult_type; | |
2673 | resultcode = xresultcode; | |
2674 | ||
2675 | if (extra_warnings) | |
2676 | { | |
2677 | tree op0_type = TREE_TYPE (orig_op0); | |
2678 | tree op1_type = TREE_TYPE (orig_op1); | |
2679 | int op0_unsigned = TREE_UNSIGNED (op0_type); | |
2680 | int op1_unsigned = TREE_UNSIGNED (op1_type); | |
2681 | ||
2682 | /* Give warnings for comparisons between signed and unsigned | |
2683 | quantities that will fail. Do not warn if the signed quantity | |
2684 | is an unsuffixed integer literal (or some static constant | |
2685 | expression involving such literals) and it is positive. | |
2686 | Do not warn if the width of the unsigned quantity is less | |
2687 | than that of the signed quantity, since in this case all | |
2688 | values of the unsigned quantity fit in the signed quantity. | |
2689 | Do not warn if the signed type is the same size as the | |
2690 | result_type since sign extension does not cause trouble in | |
2691 | this case. */ | |
2692 | /* Do the checking based on the original operand trees, so that | |
2693 | casts will be considered, but default promotions won't be. */ | |
2694 | if (op0_unsigned != op1_unsigned | |
2695 | && ((op0_unsigned | |
2696 | && TYPE_PRECISION (op0_type) >= TYPE_PRECISION (op1_type) | |
2697 | && TYPE_PRECISION (op0_type) < TYPE_PRECISION (result_type) | |
2698 | && (TREE_CODE (op1) != INTEGER_CST | |
2699 | || (TREE_CODE (op1) == INTEGER_CST | |
2700 | && INT_CST_LT (op1, integer_zero_node)))) | |
2701 | || | |
2702 | (op1_unsigned | |
2703 | && TYPE_PRECISION (op1_type) >= TYPE_PRECISION (op0_type) | |
2704 | && TYPE_PRECISION (op1_type) < TYPE_PRECISION (result_type) | |
2705 | && (TREE_CODE (op0) != INTEGER_CST | |
2706 | || (TREE_CODE (op0) == INTEGER_CST | |
2707 | && INT_CST_LT (op0, integer_zero_node)))))) | |
2708 | warning ("comparison between signed and unsigned"); | |
2709 | } | |
2710 | } | |
2711 | } | |
2712 | ||
2713 | /* At this point, RESULT_TYPE must be nonzero to avoid an error message. | |
2714 | If CONVERTED is zero, both args will be converted to type RESULT_TYPE. | |
2715 | Then the expression will be built. | |
2716 | It will be given type FINAL_TYPE if that is nonzero; | |
2717 | otherwise, it will be given type RESULT_TYPE. */ | |
2718 | ||
2719 | if (!result_type) | |
2720 | { | |
2721 | binary_op_error (code); | |
2722 | return error_mark_node; | |
2723 | } | |
2724 | ||
2725 | if (! converted) | |
2726 | { | |
2727 | if (TREE_TYPE (op0) != result_type) | |
2728 | op0 = convert (result_type, op0); | |
2729 | if (TREE_TYPE (op1) != result_type) | |
2730 | op1 = convert (result_type, op1); | |
2731 | } | |
2732 | ||
2733 | { | |
2734 | register tree result = build (resultcode, result_type, op0, op1); | |
2735 | register tree folded; | |
2736 | ||
2737 | folded = fold (result); | |
2738 | if (folded == result) | |
2739 | TREE_CONSTANT (folded) = TREE_CONSTANT (op0) & TREE_CONSTANT (op1); | |
2740 | if (final_type != 0) | |
2741 | return convert (final_type, folded); | |
2742 | return folded; | |
2743 | } | |
2744 | } | |
2745 | \f | |
2746 | /* Return a tree for the sum or difference (RESULTCODE says which) | |
2747 | of pointer PTROP and integer INTOP. */ | |
2748 | ||
2749 | static tree | |
2750 | pointer_int_sum (resultcode, ptrop, intop) | |
2751 | enum tree_code resultcode; | |
2752 | register tree ptrop, intop; | |
2753 | { | |
2754 | tree size_exp; | |
2755 | ||
2756 | register tree result; | |
2757 | register tree folded; | |
2758 | ||
2759 | /* The result is a pointer of the same type that is being added. */ | |
2760 | ||
2761 | register tree result_type = TREE_TYPE (ptrop); | |
2762 | ||
2763 | if (TREE_CODE (TREE_TYPE (result_type)) == VOID_TYPE) | |
2764 | { | |
2765 | if (pedantic || warn_pointer_arith) | |
2766 | pedwarn ("pointer of type `void *' used in arithmetic"); | |
2767 | size_exp = integer_one_node; | |
2768 | } | |
2769 | else if (TREE_CODE (TREE_TYPE (result_type)) == FUNCTION_TYPE) | |
2770 | { | |
2771 | if (pedantic || warn_pointer_arith) | |
2772 | pedwarn ("pointer to a function used in arithmetic"); | |
2773 | size_exp = integer_one_node; | |
2774 | } | |
2775 | else | |
2776 | size_exp = c_size_in_bytes (TREE_TYPE (result_type)); | |
2777 | ||
2778 | /* If what we are about to multiply by the size of the elements | |
2779 | contains a constant term, apply distributive law | |
2780 | and multiply that constant term separately. | |
2781 | This helps produce common subexpressions. */ | |
2782 | ||
2783 | if ((TREE_CODE (intop) == PLUS_EXPR || TREE_CODE (intop) == MINUS_EXPR) | |
2784 | && ! TREE_CONSTANT (intop) | |
2785 | && TREE_CONSTANT (TREE_OPERAND (intop, 1)) | |
2786 | && TREE_CONSTANT (size_exp) | |
2787 | /* If the constant comes from pointer subtraction, | |
2788 | skip this optimization--it would cause an error. */ | |
2789 | && TREE_CODE (TREE_TYPE (TREE_OPERAND (intop, 0))) == INTEGER_TYPE) | |
2790 | { | |
2791 | enum tree_code subcode = resultcode; | |
d45cf215 | 2792 | tree int_type = TREE_TYPE (intop); |
400fbf9f JW |
2793 | if (TREE_CODE (intop) == MINUS_EXPR) |
2794 | subcode = (subcode == PLUS_EXPR ? MINUS_EXPR : PLUS_EXPR); | |
d45cf215 RS |
2795 | /* Convert both subexpression types to the type of intop, |
2796 | because weird cases involving pointer arithmetic | |
2797 | can result in a sum or difference with different type args. */ | |
2798 | ptrop = build_binary_op (subcode, ptrop, | |
2799 | convert (int_type, TREE_OPERAND (intop, 1)), 1); | |
2800 | intop = convert (int_type, TREE_OPERAND (intop, 0)); | |
400fbf9f JW |
2801 | } |
2802 | ||
2803 | /* Convert the integer argument to a type the same size as a pointer | |
2804 | so the multiply won't overflow spuriously. */ | |
2805 | ||
2806 | if (TYPE_PRECISION (TREE_TYPE (intop)) != POINTER_SIZE) | |
2807 | intop = convert (type_for_size (POINTER_SIZE, 0), intop); | |
2808 | ||
2809 | /* Replace the integer argument | |
2810 | with a suitable product by the object size. */ | |
2811 | ||
2812 | intop = build_binary_op (MULT_EXPR, intop, size_exp, 1); | |
2813 | ||
2814 | /* Create the sum or difference. */ | |
2815 | ||
2816 | result = build (resultcode, result_type, ptrop, intop); | |
2817 | ||
2818 | folded = fold (result); | |
2819 | if (folded == result) | |
2820 | TREE_CONSTANT (folded) = TREE_CONSTANT (ptrop) & TREE_CONSTANT (intop); | |
2821 | return folded; | |
2822 | } | |
2823 | ||
2824 | /* Return a tree for the difference of pointers OP0 and OP1. | |
2825 | The resulting tree has type int. */ | |
2826 | ||
2827 | static tree | |
2828 | pointer_diff (op0, op1) | |
2829 | register tree op0, op1; | |
2830 | { | |
2831 | register tree result, folded; | |
2832 | tree restype = ptrdiff_type_node; | |
2833 | ||
2834 | tree target_type = TREE_TYPE (TREE_TYPE (op0)); | |
2835 | ||
2836 | if (pedantic || warn_pointer_arith) | |
2837 | { | |
2838 | if (TREE_CODE (target_type) == VOID_TYPE) | |
2839 | pedwarn ("pointer of type `void *' used in subtraction"); | |
2840 | if (TREE_CODE (target_type) == FUNCTION_TYPE) | |
2841 | pedwarn ("pointer to a function used in subtraction"); | |
2842 | } | |
2843 | ||
2844 | /* First do the subtraction as integers; | |
2845 | then drop through to build the divide operator. */ | |
2846 | ||
2847 | op0 = build_binary_op (MINUS_EXPR, convert (restype, op0), | |
2848 | convert (restype, op1), 1); | |
2849 | op1 = c_size_in_bytes (target_type); | |
2850 | ||
2851 | /* Divide by the size, in easiest possible way. */ | |
2852 | ||
2853 | result = build (EXACT_DIV_EXPR, restype, op0, op1); | |
2854 | ||
2855 | folded = fold (result); | |
2856 | if (folded == result) | |
2857 | TREE_CONSTANT (folded) = TREE_CONSTANT (op0) & TREE_CONSTANT (op1); | |
2858 | return folded; | |
2859 | } | |
2860 | \f | |
2861 | /* Construct and perhaps optimize a tree representation | |
2862 | for a unary operation. CODE, a tree_code, specifies the operation | |
2863 | and XARG is the operand. NOCONVERT nonzero suppresses | |
2864 | the default promotions (such as from short to int). */ | |
2865 | ||
2866 | tree | |
2867 | build_unary_op (code, xarg, noconvert) | |
2868 | enum tree_code code; | |
2869 | tree xarg; | |
2870 | int noconvert; | |
2871 | { | |
2872 | /* No default_conversion here. It causes trouble for ADDR_EXPR. */ | |
2873 | register tree arg = xarg; | |
2874 | register tree argtype = 0; | |
2875 | register enum tree_code typecode = TREE_CODE (TREE_TYPE (arg)); | |
2876 | char *errstring = NULL; | |
2877 | tree val; | |
2878 | ||
2879 | if (typecode == ERROR_MARK) | |
2880 | return error_mark_node; | |
2881 | if (typecode == ENUMERAL_TYPE) | |
2882 | typecode = INTEGER_TYPE; | |
2883 | ||
2884 | switch (code) | |
2885 | { | |
2886 | case CONVERT_EXPR: | |
2887 | /* This is used for unary plus, because a CONVERT_EXPR | |
2888 | is enough to prevent anybody from looking inside for | |
2889 | associativity, but won't generate any code. */ | |
2890 | if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE)) | |
2891 | errstring = "wrong type argument to unary plus"; | |
2892 | else if (!noconvert) | |
2893 | arg = default_conversion (arg); | |
2894 | break; | |
2895 | ||
2896 | case NEGATE_EXPR: | |
2897 | if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE)) | |
2898 | errstring = "wrong type argument to unary minus"; | |
2899 | else if (!noconvert) | |
2900 | arg = default_conversion (arg); | |
2901 | break; | |
2902 | ||
2903 | case BIT_NOT_EXPR: | |
2904 | if (typecode != INTEGER_TYPE) | |
2905 | errstring = "wrong type argument to bit-complement"; | |
2906 | else if (!noconvert) | |
2907 | arg = default_conversion (arg); | |
2908 | break; | |
2909 | ||
2910 | case ABS_EXPR: | |
2911 | if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE)) | |
2912 | errstring = "wrong type argument to abs"; | |
2913 | else if (!noconvert) | |
2914 | arg = default_conversion (arg); | |
2915 | break; | |
2916 | ||
2917 | case TRUTH_NOT_EXPR: | |
2918 | if (typecode != INTEGER_TYPE | |
2919 | && typecode != REAL_TYPE && typecode != POINTER_TYPE | |
2920 | /* These will convert to a pointer. */ | |
2921 | && typecode != ARRAY_TYPE && typecode != FUNCTION_TYPE) | |
2922 | { | |
2923 | errstring = "wrong type argument to unary exclamation mark"; | |
2924 | break; | |
2925 | } | |
2926 | arg = truthvalue_conversion (arg); | |
2927 | return invert_truthvalue (arg); | |
2928 | ||
2929 | case NOP_EXPR: | |
2930 | break; | |
2931 | ||
2932 | case PREINCREMENT_EXPR: | |
2933 | case POSTINCREMENT_EXPR: | |
2934 | case PREDECREMENT_EXPR: | |
2935 | case POSTDECREMENT_EXPR: | |
2936 | /* Handle complex lvalues (when permitted) | |
2937 | by reduction to simpler cases. */ | |
2938 | ||
2939 | val = unary_complex_lvalue (code, arg); | |
2940 | if (val != 0) | |
2941 | return val; | |
2942 | ||
2943 | /* Report invalid types. */ | |
2944 | ||
2945 | if (typecode != POINTER_TYPE | |
2946 | && typecode != INTEGER_TYPE && typecode != REAL_TYPE) | |
2947 | { | |
2948 | if (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR) | |
2949 | errstring ="wrong type argument to increment"; | |
2950 | else | |
2951 | errstring ="wrong type argument to decrement"; | |
2952 | break; | |
2953 | } | |
2954 | ||
2955 | { | |
2956 | register tree inc; | |
2957 | tree result_type = TREE_TYPE (arg); | |
2958 | ||
2959 | arg = get_unwidened (arg, 0); | |
2960 | argtype = TREE_TYPE (arg); | |
2961 | ||
2962 | /* Compute the increment. */ | |
2963 | ||
2964 | if (typecode == POINTER_TYPE) | |
2965 | { | |
7fc89bbe | 2966 | if ((pedantic || warn_pointer_arith) |
400fbf9f JW |
2967 | && (TREE_CODE (TREE_TYPE (result_type)) == FUNCTION_TYPE |
2968 | || TREE_CODE (TREE_TYPE (result_type)) == VOID_TYPE)) | |
2969 | pedwarn ("wrong type argument to %s", | |
2970 | ((code == PREINCREMENT_EXPR | |
2971 | || code == POSTINCREMENT_EXPR) | |
2972 | ? "increment" : "decrement")); | |
2973 | inc = c_sizeof_nowarn (TREE_TYPE (result_type)); | |
2974 | } | |
2975 | else | |
2976 | inc = integer_one_node; | |
2977 | ||
2978 | inc = convert (argtype, inc); | |
2979 | ||
2980 | /* Handle incrementing a cast-expression. */ | |
2981 | ||
2982 | while (1) | |
2983 | switch (TREE_CODE (arg)) | |
2984 | { | |
2985 | case NOP_EXPR: | |
2986 | case CONVERT_EXPR: | |
2987 | case FLOAT_EXPR: | |
2988 | case FIX_TRUNC_EXPR: | |
2989 | case FIX_FLOOR_EXPR: | |
2990 | case FIX_ROUND_EXPR: | |
2991 | case FIX_CEIL_EXPR: | |
2992 | /* If the real type has the same machine representation | |
2993 | as the type it is cast to, we can make better output | |
2994 | by adding directly to the inside of the cast. */ | |
2995 | if ((TREE_CODE (TREE_TYPE (arg)) | |
2996 | == TREE_CODE (TREE_TYPE (TREE_OPERAND (arg, 0)))) | |
2997 | && (TYPE_MODE (TREE_TYPE (arg)) | |
2998 | == TYPE_MODE (TREE_TYPE (TREE_OPERAND (arg, 0))))) | |
2999 | arg = TREE_OPERAND (arg, 0); | |
3000 | else | |
3001 | { | |
3002 | tree incremented, modify, value; | |
3003 | pedantic_lvalue_warning (CONVERT_EXPR); | |
3004 | arg = stabilize_reference (arg); | |
3005 | if (code == PREINCREMENT_EXPR || code == PREDECREMENT_EXPR) | |
3006 | value = arg; | |
3007 | else | |
3008 | value = save_expr (arg); | |
3009 | incremented = build (((code == PREINCREMENT_EXPR | |
3010 | || code == POSTINCREMENT_EXPR) | |
3011 | ? PLUS_EXPR : MINUS_EXPR), | |
3012 | argtype, value, inc); | |
3013 | TREE_SIDE_EFFECTS (incremented) = 1; | |
3014 | modify = build_modify_expr (arg, NOP_EXPR, incremented); | |
3015 | value = build (COMPOUND_EXPR, TREE_TYPE (arg), modify, value); | |
3016 | TREE_USED (value) = 1; | |
3017 | return value; | |
3018 | } | |
3019 | break; | |
3020 | ||
3021 | default: | |
3022 | goto give_up; | |
3023 | } | |
3024 | give_up: | |
3025 | ||
3026 | /* Complain about anything else that is not a true lvalue. */ | |
3027 | if (!lvalue_or_else (arg, ((code == PREINCREMENT_EXPR | |
3028 | || code == POSTINCREMENT_EXPR) | |
3029 | ? "increment" : "decrement"))) | |
3030 | return error_mark_node; | |
3031 | ||
3032 | /* Report a read-only lvalue. */ | |
26b3c423 | 3033 | if (TREE_READONLY (arg)) |
400fbf9f JW |
3034 | readonly_warning (arg, |
3035 | ((code == PREINCREMENT_EXPR | |
3036 | || code == POSTINCREMENT_EXPR) | |
3037 | ? "increment" : "decrement")); | |
3038 | ||
3039 | val = build (code, TREE_TYPE (arg), arg, inc); | |
3040 | TREE_SIDE_EFFECTS (val) = 1; | |
3041 | val = convert (result_type, val); | |
3042 | if (TREE_CODE (val) != code) | |
3043 | TREE_NO_UNUSED_WARNING (val) = 1; | |
3044 | return val; | |
3045 | } | |
3046 | ||
3047 | case ADDR_EXPR: | |
3048 | /* Note that this operation never does default_conversion | |
3049 | regardless of NOCONVERT. */ | |
3050 | ||
3051 | /* Let &* cancel out to simplify resulting code. */ | |
3052 | if (TREE_CODE (arg) == INDIRECT_REF) | |
3053 | { | |
3054 | /* Don't let this be an lvalue. */ | |
3055 | if (lvalue_p (TREE_OPERAND (arg, 0))) | |
3056 | return non_lvalue (TREE_OPERAND (arg, 0)); | |
3057 | return TREE_OPERAND (arg, 0); | |
3058 | } | |
3059 | ||
3060 | /* For &x[y], return x+y */ | |
3061 | if (TREE_CODE (arg) == ARRAY_REF) | |
3062 | { | |
3063 | if (mark_addressable (TREE_OPERAND (arg, 0)) == 0) | |
3064 | return error_mark_node; | |
3065 | return build_binary_op (PLUS_EXPR, TREE_OPERAND (arg, 0), | |
3066 | TREE_OPERAND (arg, 1), 1); | |
3067 | } | |
3068 | ||
3069 | /* Handle complex lvalues (when permitted) | |
3070 | by reduction to simpler cases. */ | |
3071 | val = unary_complex_lvalue (code, arg); | |
3072 | if (val != 0) | |
3073 | return val; | |
3074 | ||
3075 | #if 0 /* Turned off because inconsistent; | |
3076 | float f; *&(int)f = 3.4 stores in int format | |
3077 | whereas (int)f = 3.4 stores in float format. */ | |
3078 | /* Address of a cast is just a cast of the address | |
3079 | of the operand of the cast. */ | |
3080 | switch (TREE_CODE (arg)) | |
3081 | { | |
3082 | case NOP_EXPR: | |
3083 | case CONVERT_EXPR: | |
3084 | case FLOAT_EXPR: | |
3085 | case FIX_TRUNC_EXPR: | |
3086 | case FIX_FLOOR_EXPR: | |
3087 | case FIX_ROUND_EXPR: | |
3088 | case FIX_CEIL_EXPR: | |
3089 | if (pedantic) | |
3090 | pedwarn ("ANSI C forbids the address of a cast expression"); | |
3091 | return convert (build_pointer_type (TREE_TYPE (arg)), | |
3092 | build_unary_op (ADDR_EXPR, TREE_OPERAND (arg, 0), | |
3093 | 0)); | |
3094 | } | |
3095 | #endif | |
3096 | ||
3097 | /* Allow the address of a constructor if all the elements | |
3098 | are constant. */ | |
3099 | if (TREE_CODE (arg) == CONSTRUCTOR && TREE_CONSTANT (arg)) | |
3100 | ; | |
3101 | /* Anything not already handled and not a true memory reference | |
3102 | is an error. */ | |
3103 | else if (typecode != FUNCTION_TYPE && !lvalue_or_else (arg, "unary `&'")) | |
3104 | return error_mark_node; | |
3105 | ||
3106 | /* Ordinary case; arg is a COMPONENT_REF or a decl. */ | |
3107 | argtype = TREE_TYPE (arg); | |
3108 | /* If the lvalue is const or volatile, | |
3109 | merge that into the type that the address will point to. */ | |
3110 | if (TREE_CODE_CLASS (TREE_CODE (arg)) == 'd' | |
3111 | || TREE_CODE_CLASS (TREE_CODE (arg)) == 'r') | |
3112 | { | |
3113 | if (TREE_READONLY (arg) || TREE_THIS_VOLATILE (arg)) | |
3114 | argtype = c_build_type_variant (argtype, | |
3115 | TREE_READONLY (arg), | |
3116 | TREE_THIS_VOLATILE (arg)); | |
3117 | } | |
3118 | ||
3119 | argtype = build_pointer_type (argtype); | |
3120 | ||
3121 | if (mark_addressable (arg) == 0) | |
3122 | return error_mark_node; | |
3123 | ||
3124 | { | |
3125 | tree addr; | |
3126 | ||
3127 | if (TREE_CODE (arg) == COMPONENT_REF) | |
3128 | { | |
3129 | tree field = TREE_OPERAND (arg, 1); | |
3130 | ||
3131 | addr = build_unary_op (ADDR_EXPR, TREE_OPERAND (arg, 0), 0); | |
3132 | ||
3133 | if (DECL_BIT_FIELD (field)) | |
3134 | { | |
3135 | error ("attempt to take address of bit-field structure member `%s'", | |
3136 | IDENTIFIER_POINTER (DECL_NAME (field))); | |
3137 | return error_mark_node; | |
3138 | } | |
3139 | ||
3140 | addr = convert (argtype, addr); | |
3141 | ||
3142 | if (! integer_zerop (DECL_FIELD_BITPOS (field))) | |
3143 | { | |
3144 | tree offset | |
3145 | = size_binop (EASY_DIV_EXPR, DECL_FIELD_BITPOS (field), | |
3146 | size_int (BITS_PER_UNIT)); | |
3147 | int flag = TREE_CONSTANT (addr); | |
3148 | addr = fold (build (PLUS_EXPR, argtype, | |
3149 | addr, convert (argtype, offset))); | |
3150 | TREE_CONSTANT (addr) = flag; | |
3151 | } | |
3152 | } | |
3153 | else | |
3154 | addr = build1 (code, argtype, arg); | |
3155 | ||
3156 | /* Address of a static or external variable or | |
3157 | function counts as a constant */ | |
3158 | TREE_CONSTANT (addr) = staticp (arg); | |
3159 | return addr; | |
3160 | } | |
3161 | } | |
3162 | ||
3163 | if (!errstring) | |
3164 | { | |
3165 | if (argtype == 0) | |
3166 | argtype = TREE_TYPE (arg); | |
3167 | return fold (build1 (code, argtype, arg)); | |
3168 | } | |
3169 | ||
3170 | error (errstring); | |
3171 | return error_mark_node; | |
3172 | } | |
3173 | ||
3174 | #if 0 | |
3175 | /* If CONVERSIONS is a conversion expression or a nested sequence of such, | |
3176 | convert ARG with the same conversions in the same order | |
3177 | and return the result. */ | |
3178 | ||
3179 | static tree | |
3180 | convert_sequence (conversions, arg) | |
3181 | tree conversions; | |
3182 | tree arg; | |
3183 | { | |
3184 | switch (TREE_CODE (conversions)) | |
3185 | { | |
3186 | case NOP_EXPR: | |
3187 | case CONVERT_EXPR: | |
3188 | case FLOAT_EXPR: | |
3189 | case FIX_TRUNC_EXPR: | |
3190 | case FIX_FLOOR_EXPR: | |
3191 | case FIX_ROUND_EXPR: | |
3192 | case FIX_CEIL_EXPR: | |
3193 | return convert (TREE_TYPE (conversions), | |
3194 | convert_sequence (TREE_OPERAND (conversions, 0), | |
3195 | arg)); | |
3196 | ||
3197 | default: | |
3198 | return arg; | |
3199 | } | |
3200 | } | |
3201 | #endif /* 0 */ | |
3202 | ||
3203 | /* Return nonzero if REF is an lvalue valid for this language. | |
3204 | Lvalues can be assigned, unless their type has TYPE_READONLY. | |
3205 | Lvalues can have their address taken, unless they have TREE_REGDECL. */ | |
3206 | ||
3207 | int | |
3208 | lvalue_p (ref) | |
3209 | tree ref; | |
3210 | { | |
3211 | register enum tree_code code = TREE_CODE (ref); | |
3212 | ||
3213 | switch (code) | |
3214 | { | |
3215 | case COMPONENT_REF: | |
3216 | return lvalue_p (TREE_OPERAND (ref, 0)); | |
3217 | ||
3218 | case STRING_CST: | |
3219 | return 1; | |
3220 | ||
3221 | case INDIRECT_REF: | |
3222 | case ARRAY_REF: | |
3223 | case VAR_DECL: | |
3224 | case PARM_DECL: | |
3225 | case RESULT_DECL: | |
3226 | case ERROR_MARK: | |
3227 | if (TREE_CODE (TREE_TYPE (ref)) != FUNCTION_TYPE | |
3228 | && TREE_CODE (TREE_TYPE (ref)) != METHOD_TYPE) | |
3229 | return 1; | |
3230 | break; | |
3231 | } | |
3232 | return 0; | |
3233 | } | |
3234 | ||
3235 | /* Return nonzero if REF is an lvalue valid for this language; | |
3236 | otherwise, print an error message and return zero. */ | |
3237 | ||
3238 | int | |
3239 | lvalue_or_else (ref, string) | |
3240 | tree ref; | |
3241 | char *string; | |
3242 | { | |
3243 | int win = lvalue_p (ref); | |
3244 | if (! win) | |
3245 | error ("invalid lvalue in %s", string); | |
3246 | return win; | |
3247 | } | |
3248 | ||
3249 | /* Apply unary lvalue-demanding operator CODE to the expression ARG | |
3250 | for certain kinds of expressions which are not really lvalues | |
3251 | but which we can accept as lvalues. | |
3252 | ||
3253 | If ARG is not a kind of expression we can handle, return zero. */ | |
3254 | ||
3255 | static tree | |
3256 | unary_complex_lvalue (code, arg) | |
3257 | enum tree_code code; | |
3258 | tree arg; | |
3259 | { | |
3260 | /* Handle (a, b) used as an "lvalue". */ | |
3261 | if (TREE_CODE (arg) == COMPOUND_EXPR) | |
3262 | { | |
3263 | tree real_result = build_unary_op (code, TREE_OPERAND (arg, 1), 0); | |
3264 | pedantic_lvalue_warning (COMPOUND_EXPR); | |
3265 | return build (COMPOUND_EXPR, TREE_TYPE (real_result), | |
3266 | TREE_OPERAND (arg, 0), real_result); | |
3267 | } | |
3268 | ||
3269 | /* Handle (a ? b : c) used as an "lvalue". */ | |
3270 | if (TREE_CODE (arg) == COND_EXPR) | |
3271 | { | |
3272 | pedantic_lvalue_warning (COND_EXPR); | |
3273 | return (build_conditional_expr | |
3274 | (TREE_OPERAND (arg, 0), | |
3275 | build_unary_op (code, TREE_OPERAND (arg, 1), 0), | |
3276 | build_unary_op (code, TREE_OPERAND (arg, 2), 0))); | |
3277 | } | |
3278 | ||
3279 | return 0; | |
3280 | } | |
3281 | ||
3282 | /* If pedantic, warn about improper lvalue. CODE is either COND_EXPR | |
3283 | COMPOUND_EXPR, or CONVERT_EXPR (for casts). */ | |
3284 | ||
3285 | static void | |
3286 | pedantic_lvalue_warning (code) | |
3287 | enum tree_code code; | |
3288 | { | |
3289 | if (pedantic) | |
3290 | pedwarn ("ANSI C forbids use of %s expressions as lvalues", | |
3291 | code == COND_EXPR ? "conditional" | |
3292 | : code == COMPOUND_EXPR ? "compound" : "cast"); | |
3293 | } | |
3294 | \f | |
3295 | /* Warn about storing in something that is `const'. */ | |
3296 | ||
3297 | void | |
3298 | readonly_warning (arg, string) | |
3299 | tree arg; | |
3300 | char *string; | |
3301 | { | |
3302 | char buf[80]; | |
3303 | strcpy (buf, string); | |
3304 | ||
3305 | if (TREE_CODE (arg) == COMPONENT_REF) | |
3306 | { | |
3307 | if (TYPE_READONLY (TREE_TYPE (TREE_OPERAND (arg, 0)))) | |
3308 | readonly_warning (TREE_OPERAND (arg, 0), string); | |
3309 | else | |
3310 | { | |
3311 | strcat (buf, " of read-only member `%s'"); | |
3312 | pedwarn (buf, IDENTIFIER_POINTER (DECL_NAME (TREE_OPERAND (arg, 1)))); | |
3313 | } | |
3314 | } | |
3315 | else if (TREE_CODE (arg) == VAR_DECL) | |
3316 | { | |
3317 | strcat (buf, " of read-only variable `%s'"); | |
3318 | pedwarn (buf, IDENTIFIER_POINTER (DECL_NAME (arg))); | |
3319 | } | |
3320 | else | |
3321 | { | |
3322 | pedwarn ("%s of read-only location", buf); | |
3323 | } | |
3324 | } | |
3325 | \f | |
3326 | /* Mark EXP saying that we need to be able to take the | |
3327 | address of it; it should not be allocated in a register. | |
3328 | Value is 1 if successful. */ | |
3329 | ||
3330 | int | |
3331 | mark_addressable (exp) | |
3332 | tree exp; | |
3333 | { | |
3334 | register tree x = exp; | |
3335 | while (1) | |
3336 | switch (TREE_CODE (x)) | |
3337 | { | |
3338 | case ADDR_EXPR: | |
3339 | case COMPONENT_REF: | |
3340 | case ARRAY_REF: | |
3341 | x = TREE_OPERAND (x, 0); | |
3342 | break; | |
3343 | ||
3344 | case CONSTRUCTOR: | |
3345 | TREE_ADDRESSABLE (x) = 1; | |
3346 | return 1; | |
3347 | ||
3348 | case VAR_DECL: | |
3349 | case CONST_DECL: | |
3350 | case PARM_DECL: | |
3351 | case RESULT_DECL: | |
4bb6d2f8 RS |
3352 | if (TREE_REGDECL (x) && !TREE_ADDRESSABLE (x) |
3353 | && TREE_NONLOCAL (x)) | |
3354 | { | |
3355 | if (TREE_PUBLIC (x)) | |
3356 | { | |
3357 | error ("global register variable `%s' used in nested function", | |
3358 | IDENTIFIER_POINTER (DECL_NAME (x))); | |
3359 | return 0; | |
3360 | } | |
3361 | pedwarn ("register variable `%s' used in nested function", | |
3362 | IDENTIFIER_POINTER (DECL_NAME (x))); | |
3363 | } | |
3364 | else if (TREE_REGDECL (x) && !TREE_ADDRESSABLE (x)) | |
400fbf9f JW |
3365 | { |
3366 | if (TREE_PUBLIC (x)) | |
3367 | { | |
3368 | error ("address of global register variable `%s' requested", | |
3369 | IDENTIFIER_POINTER (DECL_NAME (x))); | |
3370 | return 0; | |
3371 | } | |
3372 | pedwarn ("address of register variable `%s' requested", | |
3373 | IDENTIFIER_POINTER (DECL_NAME (x))); | |
3374 | } | |
3375 | put_var_into_stack (x); | |
3376 | ||
3377 | /* drops in */ | |
3378 | case FUNCTION_DECL: | |
3379 | TREE_ADDRESSABLE (x) = 1; | |
3380 | #if 0 /* poplevel deals with this now. */ | |
3381 | if (DECL_CONTEXT (x) == 0) | |
3382 | TREE_ADDRESSABLE (DECL_ASSEMBLER_NAME (x)) = 1; | |
3383 | #endif | |
3384 | ||
3385 | default: | |
3386 | return 1; | |
3387 | } | |
3388 | } | |
3389 | \f | |
3390 | /* Build and return a conditional expression IFEXP ? OP1 : OP2. */ | |
3391 | ||
3392 | tree | |
3393 | build_conditional_expr (ifexp, op1, op2) | |
3394 | tree ifexp, op1, op2; | |
3395 | { | |
3396 | register tree type1; | |
3397 | register tree type2; | |
3398 | register enum tree_code code1; | |
3399 | register enum tree_code code2; | |
3400 | register tree result_type = NULL; | |
3401 | ||
3402 | /* If second operand is omitted, it is the same as the first one; | |
3403 | make sure it is calculated only once. */ | |
3404 | if (op1 == 0) | |
3405 | { | |
3406 | if (pedantic) | |
3407 | pedwarn ("ANSI C forbids omitting the middle term of a ?: expression"); | |
3408 | ifexp = op1 = save_expr (ifexp); | |
3409 | } | |
3410 | ||
3411 | ifexp = truthvalue_conversion (default_conversion (ifexp)); | |
3412 | ||
3413 | if (TREE_CODE (ifexp) == ERROR_MARK | |
3414 | || TREE_CODE (TREE_TYPE (op1)) == ERROR_MARK | |
3415 | || TREE_CODE (TREE_TYPE (op2)) == ERROR_MARK) | |
3416 | return error_mark_node; | |
3417 | ||
3418 | #if 0 /* Produces wrong result if within sizeof. */ | |
3419 | /* Don't promote the operands separately if they promote | |
3420 | the same way. Return the unpromoted type and let the combined | |
3421 | value get promoted if necessary. */ | |
3422 | ||
3423 | if (TREE_TYPE (op1) == TREE_TYPE (op2) | |
3424 | && TREE_CODE (TREE_TYPE (op1)) != ARRAY_TYPE | |
3425 | && TREE_CODE (TREE_TYPE (op1)) != ENUMERAL_TYPE | |
3426 | && TREE_CODE (TREE_TYPE (op1)) != FUNCTION_TYPE) | |
3427 | { | |
3428 | if (TREE_CODE (ifexp) == INTEGER_CST) | |
3429 | return (integer_zerop (ifexp) ? op2 : op1); | |
3430 | ||
3431 | return fold (build (COND_EXPR, TREE_TYPE (op1), ifexp, op1, op2)); | |
3432 | } | |
3433 | #endif | |
3434 | ||
3435 | /* They don't match; promote them both and then try to reconcile them. */ | |
3436 | ||
3437 | if (TREE_CODE (TREE_TYPE (op1)) != VOID_TYPE) | |
3438 | op1 = default_conversion (op1); | |
3439 | if (TREE_CODE (TREE_TYPE (op2)) != VOID_TYPE) | |
3440 | op2 = default_conversion (op2); | |
3441 | ||
3442 | type1 = TREE_TYPE (op1); | |
3443 | code1 = TREE_CODE (type1); | |
3444 | type2 = TREE_TYPE (op2); | |
3445 | code2 = TREE_CODE (type2); | |
3446 | ||
3447 | /* Quickly detect the usual case where op1 and op2 have the same type | |
3448 | after promotion. */ | |
3449 | if (type1 == type2) | |
3450 | result_type = type1; | |
3451 | else if ((code1 == INTEGER_TYPE || code1 == REAL_TYPE) | |
3452 | && (code2 == INTEGER_TYPE || code2 == REAL_TYPE)) | |
3453 | { | |
3454 | result_type = common_type (type1, type2); | |
3455 | } | |
3456 | else if (code1 == VOID_TYPE || code2 == VOID_TYPE) | |
3457 | { | |
3458 | if (pedantic && (code1 != VOID_TYPE || code2 != VOID_TYPE)) | |
3459 | pedwarn ("ANSI C forbids conditional expr with only one void side"); | |
3460 | result_type = void_type_node; | |
3461 | } | |
3462 | else if (code1 == POINTER_TYPE && code2 == POINTER_TYPE) | |
3463 | { | |
3464 | if (comp_target_types (type1, type2)) | |
3465 | result_type = common_type (type1, type2); | |
3466 | else if (integer_zerop (op1) && TREE_TYPE (type1) == void_type_node) | |
3467 | result_type = qualify_type (type2, type1); | |
3468 | else if (integer_zerop (op2) && TREE_TYPE (type2) == void_type_node) | |
3469 | result_type = qualify_type (type1, type2); | |
3470 | else if (TYPE_MAIN_VARIANT (TREE_TYPE (type1)) == void_type_node) | |
3471 | { | |
3472 | if (pedantic && TREE_CODE (TREE_TYPE (type2)) == FUNCTION_TYPE) | |
3473 | pedwarn ("ANSI C forbids conditional expr between `void *' and function pointer"); | |
3474 | result_type = qualify_type (type1, type2); | |
3475 | } | |
3476 | else if (TYPE_MAIN_VARIANT (TREE_TYPE (type2)) == void_type_node) | |
3477 | { | |
3478 | if (pedantic && TREE_CODE (TREE_TYPE (type1)) == FUNCTION_TYPE) | |
3479 | pedwarn ("ANSI C forbids conditional expr between `void *' and function pointer"); | |
3480 | result_type = qualify_type (type2, type1); | |
3481 | } | |
3482 | else | |
3483 | { | |
3484 | pedwarn ("pointer type mismatch in conditional expression"); | |
3485 | result_type = build_pointer_type (void_type_node); | |
3486 | } | |
3487 | } | |
3488 | else if (code1 == POINTER_TYPE && code2 == INTEGER_TYPE) | |
3489 | { | |
3490 | if (! integer_zerop (op2)) | |
3491 | pedwarn ("pointer/integer type mismatch in conditional expression"); | |
3492 | else | |
3493 | { | |
3494 | op2 = null_pointer_node; | |
3495 | #if 0 /* The spec seems to say this is permitted. */ | |
3496 | if (pedantic && TREE_CODE (type1) == FUNCTION_TYPE) | |
3497 | pedwarn ("ANSI C forbids conditional expr between 0 and function pointer"); | |
3498 | #endif | |
3499 | } | |
3500 | result_type = type1; | |
3501 | } | |
3502 | else if (code2 == POINTER_TYPE && code1 == INTEGER_TYPE) | |
3503 | { | |
3504 | if (!integer_zerop (op1)) | |
3505 | pedwarn ("pointer/integer type mismatch in conditional expression"); | |
3506 | else | |
3507 | { | |
3508 | op1 = null_pointer_node; | |
3509 | #if 0 /* The spec seems to say this is permitted. */ | |
3510 | if (pedantic && TREE_CODE (type2) == FUNCTION_TYPE) | |
3511 | pedwarn ("ANSI C forbids conditional expr between 0 and function pointer"); | |
3512 | #endif | |
3513 | } | |
3514 | result_type = type2; | |
3515 | } | |
3516 | ||
3517 | if (!result_type) | |
3518 | { | |
3519 | if (flag_cond_mismatch) | |
3520 | result_type = void_type_node; | |
3521 | else | |
3522 | { | |
3523 | error ("type mismatch in conditional expression"); | |
3524 | return error_mark_node; | |
3525 | } | |
3526 | } | |
3527 | ||
3528 | if (result_type != TREE_TYPE (op1)) | |
3529 | op1 = convert (result_type, op1); | |
3530 | if (result_type != TREE_TYPE (op2)) | |
3531 | op2 = convert (result_type, op2); | |
3532 | ||
3533 | #if 0 | |
3534 | if (code1 == RECORD_TYPE || code1 == UNION_TYPE) | |
3535 | { | |
3536 | result_type = TREE_TYPE (op1); | |
3537 | if (TREE_CONSTANT (ifexp)) | |
3538 | return (integer_zerop (ifexp) ? op2 : op1); | |
3539 | ||
3540 | if (TYPE_MODE (result_type) == BLKmode) | |
3541 | { | |
3542 | register tree tempvar | |
3543 | = build_decl (VAR_DECL, NULL_TREE, result_type); | |
3544 | register tree xop1 = build_modify_expr (tempvar, op1); | |
3545 | register tree xop2 = build_modify_expr (tempvar, op2); | |
3546 | register tree result = fold (build (COND_EXPR, result_type, | |
3547 | ifexp, xop1, xop2)); | |
3548 | ||
3549 | layout_decl (tempvar, TYPE_ALIGN (result_type)); | |
3550 | /* No way to handle variable-sized objects here. | |
3551 | I fear that the entire handling of BLKmode conditional exprs | |
3552 | needs to be redone. */ | |
3553 | if (TREE_CODE (DECL_SIZE (tempvar)) != INTEGER_CST) | |
3554 | abort (); | |
3555 | DECL_RTL (tempvar) | |
3556 | = assign_stack_local (DECL_MODE (tempvar), | |
3557 | (TREE_INT_CST_LOW (DECL_SIZE (tempvar)) | |
3558 | + BITS_PER_UNIT - 1) | |
3559 | / BITS_PER_UNIT, | |
3560 | 0); | |
3561 | ||
3562 | TREE_SIDE_EFFECTS (result) | |
3563 | = TREE_SIDE_EFFECTS (ifexp) | TREE_SIDE_EFFECTS (op1) | |
3564 | | TREE_SIDE_EFFECTS (op2); | |
3565 | return build (COMPOUND_EXPR, result_type, result, tempvar); | |
3566 | } | |
3567 | } | |
3568 | #endif /* 0 */ | |
3569 | ||
3570 | if (TREE_CODE (ifexp) == INTEGER_CST) | |
3571 | return (integer_zerop (ifexp) ? op2 : op1); | |
3572 | return fold (build (COND_EXPR, result_type, ifexp, op1, op2)); | |
3573 | } | |
3574 | \f | |
3575 | /* Given a list of expressions, return a compound expression | |
3576 | that performs them all and returns the value of the last of them. */ | |
3577 | ||
3578 | tree | |
3579 | build_compound_expr (list) | |
3580 | tree list; | |
3581 | { | |
3582 | register tree rest; | |
3583 | ||
3584 | if (TREE_CHAIN (list) == 0) | |
3585 | { | |
6dc42e49 | 3586 | #if 0 /* If something inside inhibited lvalueness, we should not override. */ |
400fbf9f JW |
3587 | /* Consider (x, y+0), which is not an lvalue since y+0 is not. */ |
3588 | ||
3589 | /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */ | |
3590 | if (TREE_CODE (list) == NON_LVALUE_EXPR) | |
3591 | list = TREE_OPERAND (list, 0); | |
3592 | #endif | |
3593 | ||
3594 | return TREE_VALUE (list); | |
3595 | } | |
3596 | ||
3597 | if (TREE_CHAIN (list) != 0 && TREE_CHAIN (TREE_CHAIN (list)) == 0) | |
3598 | { | |
3599 | /* Convert arrays to pointers when there really is a comma operator. */ | |
3600 | if (TREE_CODE (TREE_TYPE (TREE_VALUE (TREE_CHAIN (list)))) == ARRAY_TYPE) | |
3601 | TREE_VALUE (TREE_CHAIN (list)) | |
3602 | = default_conversion (TREE_VALUE (TREE_CHAIN (list))); | |
3603 | } | |
3604 | ||
3605 | rest = build_compound_expr (TREE_CHAIN (list)); | |
3606 | ||
3607 | if (! TREE_SIDE_EFFECTS (TREE_VALUE (list))) | |
3608 | return rest; | |
3609 | ||
3610 | return build (COMPOUND_EXPR, TREE_TYPE (rest), TREE_VALUE (list), rest); | |
3611 | } | |
3612 | ||
3613 | /* Build an expression representing a cast to type TYPE of expression EXPR. */ | |
3614 | ||
3615 | tree | |
3616 | build_c_cast (type, expr) | |
3617 | register tree type; | |
3618 | tree expr; | |
3619 | { | |
3620 | register tree value = expr; | |
3621 | ||
3622 | if (type == error_mark_node || expr == error_mark_node) | |
3623 | return error_mark_node; | |
3624 | type = TYPE_MAIN_VARIANT (type); | |
3625 | ||
3626 | #if 0 | |
3627 | /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */ | |
3628 | if (TREE_CODE (value) == NON_LVALUE_EXPR) | |
3629 | value = TREE_OPERAND (value, 0); | |
3630 | #endif | |
3631 | ||
3632 | if (TREE_CODE (type) == ARRAY_TYPE) | |
3633 | { | |
3634 | error ("cast specifies array type"); | |
3635 | return error_mark_node; | |
3636 | } | |
3637 | ||
3638 | if (TREE_CODE (type) == FUNCTION_TYPE) | |
3639 | { | |
3640 | error ("cast specifies function type"); | |
3641 | return error_mark_node; | |
3642 | } | |
3643 | ||
3644 | if (type == TREE_TYPE (value)) | |
3645 | { | |
3646 | if (pedantic) | |
3647 | { | |
3648 | if (TREE_CODE (type) == RECORD_TYPE | |
3649 | || TREE_CODE (type) == UNION_TYPE) | |
3650 | pedwarn ("ANSI C forbids casting nonscalar to the same type"); | |
3651 | } | |
3652 | } | |
3653 | else if (TREE_CODE (type) == UNION_TYPE) | |
3654 | { | |
3655 | tree field; | |
3656 | for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field)) | |
3657 | if (comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (field)), | |
3658 | TYPE_MAIN_VARIANT (TREE_TYPE (value)))) | |
3659 | break; | |
3660 | ||
3661 | if (field) | |
3662 | { | |
805f961c RS |
3663 | char *name; |
3664 | tree nvalue; | |
3665 | ||
400fbf9f JW |
3666 | if (pedantic) |
3667 | pedwarn ("ANSI C forbids casts to union type"); | |
805f961c RS |
3668 | if (TYPE_NAME (type) != 0) |
3669 | { | |
3670 | if (TREE_CODE (TYPE_NAME (type)) == IDENTIFIER_NODE) | |
3671 | name = IDENTIFIER_POINTER (TYPE_NAME (type)); | |
3672 | else | |
3673 | name = IDENTIFIER_POINTER (DECL_NAME (TYPE_NAME (type))); | |
3674 | } | |
3675 | else | |
3676 | name = ""; | |
3677 | return digest_init (type, build_nt (CONSTRUCTOR, NULL_TREE, | |
3678 | build_tree_list (field, value)), | |
3679 | 0, 0, 0, name); | |
400fbf9f JW |
3680 | } |
3681 | error ("cast to union type from type not present in union"); | |
3682 | return error_mark_node; | |
3683 | } | |
3684 | else | |
3685 | { | |
3686 | tree otype; | |
3687 | /* Convert functions and arrays to pointers, | |
3688 | but don't convert any other types. */ | |
3689 | if (TREE_CODE (TREE_TYPE (value)) == FUNCTION_TYPE | |
3690 | || TREE_CODE (TREE_TYPE (value)) == ARRAY_TYPE) | |
3691 | value = default_conversion (value); | |
3692 | otype = TREE_TYPE (value); | |
3693 | ||
d45cf215 | 3694 | /* Optionally warn about potentially worrisome casts. */ |
400fbf9f JW |
3695 | |
3696 | if (warn_cast_qual | |
3697 | && TREE_CODE (type) == POINTER_TYPE | |
3698 | && TREE_CODE (otype) == POINTER_TYPE) | |
3699 | { | |
3700 | if (TYPE_VOLATILE (TREE_TYPE (otype)) | |
3701 | && ! TYPE_VOLATILE (TREE_TYPE (type))) | |
3702 | pedwarn ("cast discards `volatile' from pointer target type"); | |
3703 | if (TYPE_READONLY (TREE_TYPE (otype)) | |
3704 | && ! TYPE_READONLY (TREE_TYPE (type))) | |
3705 | pedwarn ("cast discards `const' from pointer target type"); | |
3706 | } | |
3707 | ||
3708 | /* Warn about possible alignment problems. */ | |
d45cf215 | 3709 | if (STRICT_ALIGNMENT && warn_cast_align |
400fbf9f JW |
3710 | && TREE_CODE (type) == POINTER_TYPE |
3711 | && TREE_CODE (otype) == POINTER_TYPE | |
3712 | && TREE_CODE (TREE_TYPE (otype)) != VOID_TYPE | |
3713 | && TREE_CODE (TREE_TYPE (otype)) != FUNCTION_TYPE | |
3714 | && TYPE_ALIGN (TREE_TYPE (type)) > TYPE_ALIGN (TREE_TYPE (otype))) | |
3715 | warning ("cast increases required alignment of target type"); | |
400fbf9f JW |
3716 | |
3717 | if (TREE_CODE (type) == INTEGER_TYPE | |
3718 | && TREE_CODE (otype) == POINTER_TYPE | |
3719 | && TYPE_PRECISION (type) != TYPE_PRECISION (otype)) | |
3720 | warning ("cast from pointer to integer of different size"); | |
3721 | ||
3722 | if (TREE_CODE (type) == POINTER_TYPE | |
3723 | && TREE_CODE (otype) == INTEGER_TYPE | |
2918ed3c RS |
3724 | && TYPE_PRECISION (type) != TYPE_PRECISION (otype) |
3725 | /* Don't warn about converting 0 to pointer, | |
3726 | provided the 0 was explicit--not cast or made by folding. */ | |
3727 | && !(TREE_CODE (value) == INTEGER_CST && integer_zerop (value))) | |
400fbf9f JW |
3728 | warning ("cast to pointer from integer of different size"); |
3729 | ||
3730 | value = convert (type, value); | |
3731 | } | |
3732 | ||
3733 | if (value == expr && pedantic) | |
3734 | { | |
3735 | /* If pedantic, don't let a cast be an lvalue. */ | |
3736 | return non_lvalue (value); | |
3737 | } | |
3738 | return value; | |
3739 | } | |
3740 | \f | |
3741 | /* Build an assignment expression of lvalue LHS from value RHS. | |
3742 | MODIFYCODE is the code for a binary operator that we use | |
3743 | to combine the old value of LHS with RHS to get the new value. | |
3744 | Or else MODIFYCODE is NOP_EXPR meaning do a simple assignment. */ | |
3745 | ||
3746 | tree | |
3747 | build_modify_expr (lhs, modifycode, rhs) | |
3748 | tree lhs, rhs; | |
3749 | enum tree_code modifycode; | |
3750 | { | |
3751 | register tree result; | |
3752 | tree newrhs; | |
3753 | tree lhstype = TREE_TYPE (lhs); | |
3754 | tree olhstype = lhstype; | |
3755 | ||
3756 | /* Types that aren't fully specified cannot be used in assignments. */ | |
3757 | lhs = require_complete_type (lhs); | |
3758 | ||
3759 | /* Avoid duplicate error messages from operands that had errors. */ | |
3760 | if (TREE_CODE (lhs) == ERROR_MARK || TREE_CODE (rhs) == ERROR_MARK) | |
3761 | return error_mark_node; | |
3762 | ||
3763 | /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */ | |
3764 | if (TREE_CODE (rhs) == NON_LVALUE_EXPR) | |
3765 | rhs = TREE_OPERAND (rhs, 0); | |
3766 | ||
3767 | newrhs = rhs; | |
3768 | ||
3769 | /* Handle control structure constructs used as "lvalues". */ | |
3770 | ||
3771 | switch (TREE_CODE (lhs)) | |
3772 | { | |
3773 | /* Handle (a, b) used as an "lvalue". */ | |
3774 | case COMPOUND_EXPR: | |
3775 | pedantic_lvalue_warning (COMPOUND_EXPR); | |
3776 | return build (COMPOUND_EXPR, lhstype, | |
3777 | TREE_OPERAND (lhs, 0), | |
3778 | build_modify_expr (TREE_OPERAND (lhs, 1), | |
3779 | modifycode, rhs)); | |
3780 | ||
3781 | /* Handle (a ? b : c) used as an "lvalue". */ | |
3782 | case COND_EXPR: | |
3783 | pedantic_lvalue_warning (COND_EXPR); | |
3784 | rhs = save_expr (rhs); | |
3785 | { | |
3786 | /* Produce (a ? (b = rhs) : (c = rhs)) | |
3787 | except that the RHS goes through a save-expr | |
3788 | so the code to compute it is only emitted once. */ | |
3789 | tree cond | |
3790 | = build_conditional_expr (TREE_OPERAND (lhs, 0), | |
3791 | build_modify_expr (TREE_OPERAND (lhs, 1), | |
3792 | modifycode, rhs), | |
3793 | build_modify_expr (TREE_OPERAND (lhs, 2), | |
3794 | modifycode, rhs)); | |
3795 | /* Make sure the code to compute the rhs comes out | |
3796 | before the split. */ | |
3797 | return build (COMPOUND_EXPR, TREE_TYPE (lhs), | |
3798 | /* But cast it to void to avoid an "unused" error. */ | |
3799 | convert (void_type_node, rhs), cond); | |
3800 | } | |
3801 | } | |
3802 | ||
3803 | /* If a binary op has been requested, combine the old LHS value with the RHS | |
3804 | producing the value we should actually store into the LHS. */ | |
3805 | ||
3806 | if (modifycode != NOP_EXPR) | |
3807 | { | |
3808 | lhs = stabilize_reference (lhs); | |
3809 | newrhs = build_binary_op (modifycode, lhs, rhs, 1); | |
3810 | } | |
3811 | ||
3812 | /* Handle a cast used as an "lvalue". | |
3813 | We have already performed any binary operator using the value as cast. | |
3814 | Now convert the result to the cast type of the lhs, | |
3815 | and then true type of the lhs and store it there; | |
3816 | then convert result back to the cast type to be the value | |
3817 | of the assignment. */ | |
3818 | ||
3819 | switch (TREE_CODE (lhs)) | |
3820 | { | |
3821 | case NOP_EXPR: | |
3822 | case CONVERT_EXPR: | |
3823 | case FLOAT_EXPR: | |
3824 | case FIX_TRUNC_EXPR: | |
3825 | case FIX_FLOOR_EXPR: | |
3826 | case FIX_ROUND_EXPR: | |
3827 | case FIX_CEIL_EXPR: | |
3828 | if (TREE_CODE (TREE_TYPE (newrhs)) == ARRAY_TYPE | |
3829 | || TREE_CODE (TREE_TYPE (newrhs)) == FUNCTION_TYPE) | |
3830 | newrhs = default_conversion (newrhs); | |
3831 | { | |
3832 | tree inner_lhs = TREE_OPERAND (lhs, 0); | |
3833 | tree result; | |
3834 | result = build_modify_expr (inner_lhs, NOP_EXPR, | |
3835 | convert (TREE_TYPE (inner_lhs), | |
3836 | convert (lhstype, newrhs))); | |
3837 | pedantic_lvalue_warning (CONVERT_EXPR); | |
3838 | return convert (TREE_TYPE (lhs), result); | |
3839 | } | |
3840 | } | |
3841 | ||
3842 | /* Now we have handled acceptable kinds of LHS that are not truly lvalues. | |
3843 | Reject anything strange now. */ | |
3844 | ||
3845 | if (!lvalue_or_else (lhs, "assignment")) | |
3846 | return error_mark_node; | |
3847 | ||
3848 | /* Warn about storing in something that is `const'. */ | |
3849 | ||
3850 | if (TREE_READONLY (lhs) || TYPE_READONLY (lhstype) | |
3851 | || ((TREE_CODE (lhstype) == RECORD_TYPE | |
3852 | || TREE_CODE (lhstype) == UNION_TYPE) | |
3853 | && C_TYPE_FIELDS_READONLY (lhstype))) | |
3854 | readonly_warning (lhs, "assignment"); | |
3855 | ||
3856 | /* If storing into a structure or union member, | |
3857 | it has probably been given type `int'. | |
3858 | Compute the type that would go with | |
3859 | the actual amount of storage the member occupies. */ | |
3860 | ||
3861 | if (TREE_CODE (lhs) == COMPONENT_REF | |
3862 | && (TREE_CODE (lhstype) == INTEGER_TYPE | |
3863 | || TREE_CODE (lhstype) == REAL_TYPE | |
3864 | || TREE_CODE (lhstype) == ENUMERAL_TYPE)) | |
3865 | lhstype = TREE_TYPE (get_unwidened (lhs, 0)); | |
3866 | ||
3867 | /* If storing in a field that is in actuality a short or narrower than one, | |
3868 | we must store in the field in its actual type. */ | |
3869 | ||
3870 | if (lhstype != TREE_TYPE (lhs)) | |
3871 | { | |
3872 | lhs = copy_node (lhs); | |
3873 | TREE_TYPE (lhs) = lhstype; | |
3874 | } | |
3875 | ||
3876 | /* Convert new value to destination type. */ | |
3877 | ||
3878 | newrhs = convert_for_assignment (lhstype, newrhs, "assignment", | |
3879 | NULL_TREE, 0); | |
3880 | if (TREE_CODE (newrhs) == ERROR_MARK) | |
3881 | return error_mark_node; | |
3882 | ||
3883 | result = build (MODIFY_EXPR, lhstype, lhs, newrhs); | |
3884 | TREE_SIDE_EFFECTS (result) = 1; | |
3885 | ||
3886 | /* If we got the LHS in a different type for storing in, | |
3887 | convert the result back to the nominal type of LHS | |
3888 | so that the value we return always has the same type | |
3889 | as the LHS argument. */ | |
3890 | ||
3891 | if (olhstype == TREE_TYPE (result)) | |
3892 | return result; | |
3893 | return convert_for_assignment (olhstype, result, "assignment", NULL_TREE, 0); | |
3894 | } | |
3895 | \f | |
3896 | /* Convert value RHS to type TYPE as preparation for an assignment | |
3897 | to an lvalue of type TYPE. | |
3898 | The real work of conversion is done by `convert'. | |
3899 | The purpose of this function is to generate error messages | |
3900 | for assignments that are not allowed in C. | |
3901 | ERRTYPE is a string to use in error messages: | |
3902 | "assignment", "return", etc. If it is null, this is parameter passing | |
d45cf215 RS |
3903 | for a function call (and different error messages are output). Otherwise, |
3904 | it may be a name stored in the spelling stack and interpreted by | |
3905 | get_spelling. | |
400fbf9f JW |
3906 | |
3907 | FUNNAME is the name of the function being called, | |
3908 | as an IDENTIFIER_NODE, or null. | |
3909 | PARMNUM is the number of the argument, for printing in error messages. */ | |
3910 | ||
3911 | static tree | |
3912 | convert_for_assignment (type, rhs, errtype, funname, parmnum) | |
3913 | tree type, rhs; | |
3914 | char *errtype; | |
3915 | tree funname; | |
3916 | int parmnum; | |
3917 | { | |
3918 | register enum tree_code codel = TREE_CODE (type); | |
3919 | register tree rhstype; | |
3920 | register enum tree_code coder; | |
3921 | ||
3922 | /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */ | |
3923 | if (TREE_CODE (rhs) == NON_LVALUE_EXPR) | |
3924 | rhs = TREE_OPERAND (rhs, 0); | |
3925 | ||
3926 | if (TREE_CODE (TREE_TYPE (rhs)) == ARRAY_TYPE | |
3927 | || TREE_CODE (TREE_TYPE (rhs)) == FUNCTION_TYPE) | |
3928 | rhs = default_conversion (rhs); | |
3929 | ||
3930 | rhstype = TREE_TYPE (rhs); | |
3931 | coder = TREE_CODE (rhstype); | |
3932 | ||
3933 | if (coder == ERROR_MARK) | |
3934 | return error_mark_node; | |
3935 | ||
3936 | if (TYPE_MAIN_VARIANT (type) == TYPE_MAIN_VARIANT (rhstype)) | |
3937 | return rhs; | |
3938 | ||
3939 | if (coder == VOID_TYPE) | |
3940 | { | |
3941 | error ("void value not ignored as it ought to be"); | |
3942 | return error_mark_node; | |
3943 | } | |
3944 | /* Arithmetic types all interconvert, and enum is treated like int. */ | |
3945 | if ((codel == INTEGER_TYPE || codel == REAL_TYPE || codel == ENUMERAL_TYPE) | |
3946 | && | |
3947 | (coder == INTEGER_TYPE || coder == REAL_TYPE || coder == ENUMERAL_TYPE)) | |
3948 | { | |
3949 | return convert (type, rhs); | |
3950 | } | |
3951 | /* Conversions among pointers */ | |
3952 | else if (codel == POINTER_TYPE && coder == POINTER_TYPE) | |
3953 | { | |
3954 | register tree ttl = TREE_TYPE (type); | |
3955 | register tree ttr = TREE_TYPE (rhstype); | |
3956 | ||
3957 | /* Any non-function converts to a [const][volatile] void * | |
3958 | and vice versa; otherwise, targets must be the same. | |
3959 | Meanwhile, the lhs target must have all the qualifiers of the rhs. */ | |
3960 | if (TYPE_MAIN_VARIANT (ttl) == void_type_node | |
3961 | || TYPE_MAIN_VARIANT (ttr) == void_type_node | |
3962 | || comp_target_types (type, rhstype) | |
3963 | || (!pedantic /* Unless pedantic, mix signed and unsigned. */ | |
3964 | && TREE_CODE (ttl) == INTEGER_TYPE | |
3965 | && TREE_CODE (ttr) == INTEGER_TYPE | |
3966 | && TYPE_PRECISION (ttl) == TYPE_PRECISION (ttr))) | |
3967 | { | |
3968 | if (pedantic | |
3969 | && ((TYPE_MAIN_VARIANT (ttl) == void_type_node | |
3970 | && TREE_CODE (ttr) == FUNCTION_TYPE) | |
3971 | || | |
3972 | (TYPE_MAIN_VARIANT (ttr) == void_type_node | |
3973 | && !integer_zerop (rhs) | |
3974 | && TREE_CODE (ttl) == FUNCTION_TYPE))) | |
3975 | warn_for_assignment ("ANSI forbids %s between function pointer and `void *'", | |
d45cf215 | 3976 | get_spelling (errtype), funname, parmnum); |
400fbf9f JW |
3977 | /* Const and volatile mean something different for function types, |
3978 | so the usual warnings are not appropriate. */ | |
3979 | else if (TREE_CODE (ttr) != FUNCTION_TYPE | |
3980 | || TREE_CODE (ttl) != FUNCTION_TYPE) | |
3981 | { | |
3982 | if (! TYPE_READONLY (ttl) && TYPE_READONLY (ttr)) | |
3983 | warn_for_assignment ("%s discards `const' from pointer target type", | |
d45cf215 | 3984 | get_spelling (errtype), funname, parmnum); |
400fbf9f JW |
3985 | if (! TYPE_VOLATILE (ttl) && TYPE_VOLATILE (ttr)) |
3986 | warn_for_assignment ("%s discards `volatile' from pointer target type", | |
d45cf215 | 3987 | get_spelling (errtype), funname, parmnum); |
400fbf9f JW |
3988 | } |
3989 | else | |
3990 | { | |
3991 | /* Because const and volatile on functions are restrictions | |
3992 | that say the function will not do certain things, | |
3993 | it is okay to use a const or volatile function | |
3994 | where an ordinary one is wanted, but not vice-versa. */ | |
3995 | if (TYPE_READONLY (ttl) && ! TYPE_READONLY (ttr)) | |
3996 | warn_for_assignment ("%s makes `const *' function pointer from non-const", | |
d45cf215 | 3997 | get_spelling (errtype), funname, parmnum); |
400fbf9f JW |
3998 | if (TYPE_VOLATILE (ttl) && ! TYPE_VOLATILE (ttr)) |
3999 | warn_for_assignment ("%s makes `volatile *' function pointer from non-volatile", | |
d45cf215 | 4000 | get_spelling (errtype), funname, parmnum); |
400fbf9f JW |
4001 | } |
4002 | } | |
4003 | else if (unsigned_type (TYPE_MAIN_VARIANT (ttl)) | |
4004 | == unsigned_type (TYPE_MAIN_VARIANT (ttr))) | |
4005 | warn_for_assignment ("pointer targets in %s differ in signedness", | |
d45cf215 | 4006 | get_spelling (errtype), funname, parmnum); |
400fbf9f JW |
4007 | else |
4008 | warn_for_assignment ("%s from incompatible pointer type", | |
d45cf215 | 4009 | get_spelling (errtype), funname, parmnum); |
400fbf9f JW |
4010 | return convert (type, rhs); |
4011 | } | |
4012 | else if (codel == POINTER_TYPE && coder == INTEGER_TYPE) | |
4013 | { | |
2918ed3c RS |
4014 | /* An explicit constant 0 can convert to a pointer, |
4015 | but not a 0 that results from casting or folding. */ | |
4016 | if (! (TREE_CODE (rhs) == INTEGER_CST && integer_zerop (rhs))) | |
400fbf9f JW |
4017 | { |
4018 | warn_for_assignment ("%s makes pointer from integer without a cast", | |
d45cf215 | 4019 | get_spelling (errtype), funname, parmnum); |
400fbf9f JW |
4020 | return convert (type, rhs); |
4021 | } | |
4022 | return null_pointer_node; | |
4023 | } | |
4024 | else if (codel == INTEGER_TYPE && coder == POINTER_TYPE) | |
4025 | { | |
4026 | warn_for_assignment ("%s makes integer from pointer without a cast", | |
d45cf215 | 4027 | get_spelling (errtype), funname, parmnum); |
400fbf9f JW |
4028 | return convert (type, rhs); |
4029 | } | |
4030 | ||
4031 | if (!errtype) | |
4032 | { | |
4033 | if (funname) | |
4034 | error ("incompatible type for argument %d of `%s'", | |
4035 | parmnum, IDENTIFIER_POINTER (funname)); | |
4036 | else | |
4037 | error ("incompatible type for argument %d of indirect function call", | |
4038 | parmnum); | |
4039 | } | |
4040 | else | |
d45cf215 | 4041 | error ("incompatible types in %s", get_spelling (errtype)); |
400fbf9f JW |
4042 | |
4043 | return error_mark_node; | |
4044 | } | |
4045 | ||
4046 | /* Print a warning using MSG. | |
4047 | It gets OPNAME as its one parameter. | |
4048 | If OPNAME is null, it is replaced by "passing arg ARGNUM of `FUNCTION'". | |
4049 | FUNCTION and ARGNUM are handled specially if we are building an | |
4050 | Objective-C selector. */ | |
4051 | ||
4052 | static void | |
4053 | warn_for_assignment (msg, opname, function, argnum) | |
4054 | char *msg; | |
4055 | char *opname; | |
4056 | tree function; | |
4057 | int argnum; | |
4058 | { | |
4059 | static char argstring[] = "passing arg %d of `%s'"; | |
4060 | static char argnofun[] = "passing arg %d"; | |
4061 | ||
4062 | if (opname == 0) | |
4063 | { | |
4064 | tree selector = maybe_building_objc_message_expr (); | |
4065 | ||
4066 | if (selector && argnum > 2) | |
4067 | { | |
4068 | function = selector; | |
4069 | argnum -= 2; | |
4070 | } | |
4071 | if (function) | |
4072 | { | |
4073 | /* Function name is known; supply it. */ | |
4074 | opname = (char *) alloca (IDENTIFIER_LENGTH (function) | |
4075 | + sizeof (argstring) + 25 /*%d*/ + 1); | |
4076 | sprintf (opname, argstring, argnum, IDENTIFIER_POINTER (function)); | |
4077 | } | |
4078 | else | |
4079 | { | |
4080 | /* Function name unknown (call through ptr); just give arg number. */ | |
4081 | opname = (char *) alloca (sizeof (argnofun) + 25 /*%d*/ + 1); | |
4082 | sprintf (opname, argnofun, argnum); | |
4083 | } | |
4084 | } | |
4085 | pedwarn (msg, opname); | |
4086 | } | |
4087 | \f | |
4088 | /* Return nonzero if VALUE is a valid constant-valued expression | |
4089 | for use in initializing a static variable; one that can be an | |
4090 | element of a "constant" initializer. | |
4091 | ||
4092 | Return null_pointer_node if the value is absolute; | |
4093 | if it is relocatable, return the variable that determines the relocation. | |
4094 | We assume that VALUE has been folded as much as possible; | |
4095 | therefore, we do not need to check for such things as | |
4096 | arithmetic-combinations of integers. */ | |
4097 | ||
4098 | static tree | |
4099 | initializer_constant_valid_p (value) | |
4100 | tree value; | |
4101 | { | |
4102 | switch (TREE_CODE (value)) | |
4103 | { | |
4104 | case CONSTRUCTOR: | |
4105 | return TREE_STATIC (value) ? null_pointer_node : 0; | |
4106 | ||
4107 | case INTEGER_CST: | |
4108 | case REAL_CST: | |
4109 | case STRING_CST: | |
4110 | return null_pointer_node; | |
4111 | ||
4112 | case ADDR_EXPR: | |
4113 | return TREE_OPERAND (value, 0); | |
4114 | ||
4115 | case NON_LVALUE_EXPR: | |
4116 | return initializer_constant_valid_p (TREE_OPERAND (value, 0)); | |
4117 | ||
4118 | case CONVERT_EXPR: | |
4119 | case NOP_EXPR: | |
4120 | /* Allow conversions between pointer types. */ | |
4121 | if (TREE_CODE (TREE_TYPE (value)) == POINTER_TYPE | |
4122 | && TREE_CODE (TREE_TYPE (TREE_OPERAND (value, 0))) == POINTER_TYPE) | |
4123 | return initializer_constant_valid_p (TREE_OPERAND (value, 0)); | |
4124 | /* Allow conversions between real types. */ | |
4125 | if (TREE_CODE (TREE_TYPE (value)) == REAL_TYPE | |
4126 | && TREE_CODE (TREE_TYPE (TREE_OPERAND (value, 0))) == REAL_TYPE) | |
4127 | return initializer_constant_valid_p (TREE_OPERAND (value, 0)); | |
4128 | /* Allow length-preserving conversions between integer types. */ | |
4129 | if (TREE_CODE (TREE_TYPE (value)) == INTEGER_TYPE | |
4130 | && TREE_CODE (TREE_TYPE (TREE_OPERAND (value, 0))) == INTEGER_TYPE | |
4131 | && tree_int_cst_equal (TYPE_SIZE (TREE_TYPE (value)), | |
4132 | TYPE_SIZE (TREE_TYPE (TREE_OPERAND (value, 0))))) | |
4133 | return initializer_constant_valid_p (TREE_OPERAND (value, 0)); | |
4134 | /* Allow conversions between integer types only if explicit value. */ | |
4135 | if (TREE_CODE (TREE_TYPE (value)) == INTEGER_TYPE | |
4136 | && TREE_CODE (TREE_TYPE (TREE_OPERAND (value, 0))) == INTEGER_TYPE) | |
4137 | { | |
4138 | tree inner = initializer_constant_valid_p (TREE_OPERAND (value, 0)); | |
4139 | if (inner == null_pointer_node) | |
4140 | return null_pointer_node; | |
4141 | return 0; | |
4142 | } | |
4143 | /* Allow (int) &foo. */ | |
4144 | if (TREE_CODE (TREE_TYPE (value)) == INTEGER_TYPE | |
4145 | && TREE_CODE (TREE_TYPE (TREE_OPERAND (value, 0))) == POINTER_TYPE | |
4146 | && tree_int_cst_equal (TYPE_SIZE (TREE_TYPE (value)), | |
4147 | TYPE_SIZE (TREE_TYPE (TREE_OPERAND (value, 0))))) | |
4148 | return initializer_constant_valid_p (TREE_OPERAND (value, 0)); | |
805f961c RS |
4149 | /* Allow conversions to union types if the value inside is okay. */ |
4150 | if (TREE_CODE (TREE_TYPE (value)) == UNION_TYPE) | |
4151 | return initializer_constant_valid_p (TREE_OPERAND (value, 0)); | |
400fbf9f JW |
4152 | return 0; |
4153 | ||
4154 | case PLUS_EXPR: | |
4155 | { | |
4156 | tree valid0 = initializer_constant_valid_p (TREE_OPERAND (value, 0)); | |
4157 | tree valid1 = initializer_constant_valid_p (TREE_OPERAND (value, 1)); | |
4158 | /* If either term is absolute, use the other terms relocation. */ | |
4159 | if (valid0 == null_pointer_node) | |
4160 | return valid1; | |
4161 | if (valid1 == null_pointer_node) | |
4162 | return valid0; | |
4163 | return 0; | |
4164 | } | |
4165 | ||
4166 | case MINUS_EXPR: | |
4167 | { | |
4168 | tree valid0 = initializer_constant_valid_p (TREE_OPERAND (value, 0)); | |
4169 | tree valid1 = initializer_constant_valid_p (TREE_OPERAND (value, 1)); | |
4170 | /* Win if second argument is absolute. */ | |
4171 | if (valid1 == null_pointer_node) | |
4172 | return valid0; | |
4173 | /* Win if both arguments have the same relocation. | |
4174 | Then the value is absolute. */ | |
4175 | if (valid0 == valid1) | |
4176 | return null_pointer_node; | |
4177 | return 0; | |
4178 | } | |
4179 | } | |
4180 | ||
4181 | return 0; | |
4182 | } | |
4183 | \f | |
4184 | /* Perform appropriate conversions on the initial value of a variable, | |
4185 | store it in the declaration DECL, | |
4186 | and print any error messages that are appropriate. | |
4187 | If the init is invalid, store an ERROR_MARK. */ | |
4188 | ||
4189 | void | |
4190 | store_init_value (decl, init) | |
4191 | tree decl, init; | |
4192 | { | |
4193 | register tree value, type; | |
4194 | ||
4195 | /* If variable's type was invalidly declared, just ignore it. */ | |
4196 | ||
4197 | type = TREE_TYPE (decl); | |
4198 | if (TREE_CODE (type) == ERROR_MARK) | |
4199 | return; | |
4200 | ||
4201 | /* Digest the specified initializer into an expression. */ | |
4202 | ||
4203 | value = digest_init (type, init, 0, TREE_STATIC (decl), | |
4204 | TREE_STATIC (decl) || pedantic, | |
4205 | IDENTIFIER_POINTER (DECL_NAME (decl))); | |
4206 | ||
4207 | /* Store the expression if valid; else report error. */ | |
4208 | ||
4209 | #if 0 | |
4210 | /* Note that this is the only place we can detect the error | |
4211 | in a case such as struct foo bar = (struct foo) { x, y }; | |
d45cf215 | 4212 | where there is one initial value which is a constructor expression. */ |
400fbf9f JW |
4213 | if (value == error_mark_node) |
4214 | ; | |
4215 | else if (TREE_STATIC (decl) && ! TREE_CONSTANT (value)) | |
4216 | { | |
4217 | error ("initializer for static variable is not constant"); | |
4218 | value = error_mark_node; | |
4219 | } | |
4220 | else if (TREE_STATIC (decl) | |
4221 | && initializer_constant_valid_p (value) == 0) | |
4222 | { | |
4223 | error ("initializer for static variable uses complicated arithmetic"); | |
4224 | value = error_mark_node; | |
4225 | } | |
4226 | else | |
4227 | { | |
4228 | if (pedantic && TREE_CODE (value) == CONSTRUCTOR) | |
4229 | { | |
4230 | if (! TREE_CONSTANT (value)) | |
4231 | pedwarn ("aggregate initializer is not constant"); | |
4232 | else if (! TREE_STATIC (value)) | |
4233 | pedwarn ("aggregate initializer uses complicated arithmetic"); | |
4234 | } | |
4235 | } | |
4236 | #endif | |
4237 | ||
26b3c423 RS |
4238 | /* ANSI wants warnings about out-of-range constant initializers. */ |
4239 | constant_expression_warning (value); | |
4240 | ||
400fbf9f JW |
4241 | DECL_INITIAL (decl) = value; |
4242 | } | |
4243 | \f | |
d45cf215 RS |
4244 | /* Methods for storing and printing names for error messages. |
4245 | ||
4246 | /* Implement a spelling stack that allows components of a name to be pushed | |
4247 | and popped. Each element on the stack is this structure. */ | |
4248 | ||
4249 | struct spelling | |
4250 | { | |
4251 | int kind; | |
4252 | union | |
4253 | { | |
4254 | int i; | |
4255 | char *s; | |
4256 | } u; | |
4257 | }; | |
4258 | ||
4259 | #define SPELLING_STRING 1 | |
4260 | #define SPELLING_MEMBER 2 | |
4261 | #define SPELLING_BOUNDS 3 | |
4262 | ||
4263 | static struct spelling *spelling; /* Next stack element (unused). */ | |
4264 | static struct spelling *spelling_base; /* Spelling stack base. */ | |
4265 | static int spelling_size; /* Size of the spelling stack. */ | |
4266 | ||
4267 | /* Macros to save and restore the spelling stack around push_... functions. | |
4268 | Alternative to SAVE_SPELLING_STACK. */ | |
4269 | ||
4270 | #define SPELLING_DEPTH() (spelling - spelling_base) | |
4271 | #define RESTORE_SPELLING_DEPTH(depth) (spelling = spelling_base + depth) | |
4272 | ||
4273 | /* Save and restore the spelling stack around arbitrary C code. */ | |
4274 | ||
4275 | #define SAVE_SPELLING_DEPTH(code) \ | |
4276 | { \ | |
4277 | int __depth = SPELLING_DEPTH (); \ | |
4278 | code; \ | |
4279 | RESTORE_SPELLING_DEPTH (__depth); \ | |
4280 | } | |
4281 | ||
4282 | /* Push an element on the spelling stack with type KIND and assign VALUE | |
4283 | to MEMBER. */ | |
4284 | ||
4285 | #define PUSH_SPELLING(KIND, VALUE, MEMBER) \ | |
4286 | { \ | |
4287 | int depth = SPELLING_DEPTH (); \ | |
4288 | \ | |
4289 | if (depth >= spelling_size) \ | |
4290 | { \ | |
4291 | spelling_size += 10; \ | |
4292 | if (spelling_base == 0) \ | |
4293 | spelling_base \ | |
4294 | = (struct spelling *) xmalloc (spelling_size * sizeof (struct spelling)); \ | |
4295 | else \ | |
4296 | spelling_base \ | |
4297 | = (struct spelling *) xrealloc (spelling_base, \ | |
4298 | spelling_size * sizeof (struct spelling)); \ | |
4299 | RESTORE_SPELLING_DEPTH (depth); \ | |
4300 | } \ | |
4301 | \ | |
4302 | spelling->kind = (KIND); \ | |
4303 | spelling->MEMBER = (VALUE); \ | |
4304 | spelling++; \ | |
4305 | } | |
4306 | ||
4307 | /* Push STRING on the stack. Printed literally. */ | |
4308 | ||
4309 | static void | |
4310 | push_string (string) | |
4311 | char *string; | |
4312 | { | |
4313 | PUSH_SPELLING (SPELLING_STRING, string, u.s); | |
4314 | } | |
4315 | ||
4316 | /* Push a member name on the stack. Printed as '.' STRING. */ | |
4317 | ||
4318 | static void | |
4319 | push_member_name (string) | |
4320 | char *string; | |
4321 | { | |
4322 | PUSH_SPELLING (SPELLING_MEMBER, string, u.s); | |
4323 | } | |
4324 | ||
4325 | /* Push an array bounds on the stack. Printed as [BOUNDS]. */ | |
4326 | ||
4327 | static void | |
4328 | push_array_bounds (bounds) | |
4329 | int bounds; | |
4330 | { | |
4331 | PUSH_SPELLING (SPELLING_BOUNDS, bounds, u.i); | |
4332 | } | |
4333 | ||
4334 | /* Compute the maximum size in bytes of the printed spelling. */ | |
4335 | ||
4336 | static int | |
4337 | spelling_length () | |
4338 | { | |
4339 | register int size = 0; | |
4340 | register struct spelling *p; | |
4341 | ||
4342 | for (p = spelling_base; p < spelling; p++) | |
4343 | { | |
4344 | if (p->kind == SPELLING_BOUNDS) | |
4345 | size += 25; | |
4346 | else | |
4347 | size += strlen (p->u.s) + 1; | |
4348 | } | |
4349 | ||
4350 | return size; | |
4351 | } | |
4352 | ||
4353 | /* Print the spelling to BUFFER and return it. */ | |
4354 | ||
4355 | static char * | |
4356 | print_spelling (buffer) | |
4357 | register char *buffer; | |
4358 | { | |
4359 | register char *d = buffer; | |
4360 | register char *s; | |
4361 | register struct spelling *p; | |
4362 | ||
4363 | for (p = spelling_base; p < spelling; p++) | |
4364 | if (p->kind == SPELLING_BOUNDS) | |
4365 | { | |
4366 | sprintf (d, "[%d]", p->u.i); | |
4367 | d += strlen (d); | |
4368 | } | |
4369 | else | |
4370 | { | |
4371 | if (p->kind == SPELLING_MEMBER) | |
4372 | *d++ = '.'; | |
4373 | for (s = p->u.s; *d = *s++; d++) | |
4374 | ; | |
4375 | } | |
4376 | *d++ = '\0'; | |
4377 | return buffer; | |
4378 | } | |
4379 | ||
4380 | /* Provide a means to pass component names derived from the spelling stack. */ | |
4381 | ||
4382 | char initialization_message; | |
4383 | ||
4384 | /* Interpret the spelling of the given ERRTYPE message. */ | |
4385 | ||
4386 | static char * | |
4387 | get_spelling (errtype) | |
4388 | char *errtype; | |
4389 | { | |
4390 | static char *buffer; | |
4391 | static int size = -1; | |
4392 | ||
4393 | if (errtype == &initialization_message) | |
4394 | { | |
4395 | /* Avoid counting chars */ | |
4396 | static char message[] = "initialization of `%s'"; | |
4397 | register int needed = sizeof (message) + spelling_length () + 1; | |
047de90b | 4398 | char *temp; |
d45cf215 RS |
4399 | |
4400 | if (size < 0) | |
4401 | buffer = (char *) xmalloc (size = needed); | |
4402 | if (needed > size) | |
4403 | buffer = (char *) xrealloc (buffer, size = needed); | |
4404 | ||
047de90b RS |
4405 | temp = (char *) alloca (needed); |
4406 | sprintf (buffer, message, print_spelling (temp)); | |
d45cf215 RS |
4407 | return buffer; |
4408 | } | |
4409 | ||
4410 | return errtype; | |
4411 | } | |
4412 | ||
400fbf9f JW |
4413 | /* Issue an error message for a bad initializer component. |
4414 | FORMAT describes the message. OFWHAT is the name for the component. | |
4415 | LOCAL is a format string for formatting the insertion of the name | |
4416 | into the message. | |
4417 | ||
d45cf215 | 4418 | If OFWHAT is null, the component name is stored on the spelling stack. |
6dc42e49 | 4419 | If the component name is a null string, then LOCAL is omitted entirely. */ |
400fbf9f JW |
4420 | |
4421 | void | |
4422 | error_init (format, local, ofwhat) | |
4423 | char *format, *local, *ofwhat; | |
4424 | { | |
d45cf215 RS |
4425 | char *buffer; |
4426 | ||
4427 | if (ofwhat == 0) | |
4428 | ofwhat = print_spelling (alloca (spelling_length () + 1)); | |
4429 | buffer = (char *) alloca (strlen (local) + strlen (ofwhat) + 2); | |
400fbf9f JW |
4430 | |
4431 | if (*ofwhat) | |
4432 | sprintf (buffer, local, ofwhat); | |
4433 | else | |
4434 | buffer[0] = 0; | |
4435 | ||
4436 | error (format, buffer); | |
4437 | } | |
4438 | ||
4439 | /* Issue a pedantic warning for a bad initializer component. | |
4440 | FORMAT describes the message. OFWHAT is the name for the component. | |
4441 | LOCAL is a format string for formatting the insertion of the name | |
4442 | into the message. | |
4443 | ||
d45cf215 | 4444 | If OFWHAT is null, the component name is stored on the spelling stack. |
6dc42e49 | 4445 | If the component name is a null string, then LOCAL is omitted entirely. */ |
400fbf9f JW |
4446 | |
4447 | void | |
4448 | pedwarn_init (format, local, ofwhat) | |
4449 | char *format, *local, *ofwhat; | |
4450 | { | |
d45cf215 RS |
4451 | char *buffer; |
4452 | ||
4453 | if (ofwhat == 0) | |
4454 | ofwhat = print_spelling (alloca (spelling_length () + 1)); | |
4455 | buffer = (char *) alloca (strlen (local) + strlen (ofwhat) + 2); | |
400fbf9f JW |
4456 | |
4457 | if (*ofwhat) | |
4458 | sprintf (buffer, local, ofwhat); | |
4459 | else | |
4460 | buffer[0] = 0; | |
4461 | ||
4462 | pedwarn (format, buffer); | |
4463 | } | |
4464 | \f | |
4465 | /* Digest the parser output INIT as an initializer for type TYPE. | |
4466 | Return a C expression of type TYPE to represent the initial value. | |
4467 | ||
4468 | If TAIL is nonzero, it points to a variable holding a list of elements | |
4469 | of which INIT is the first. We update the list stored there by | |
4470 | removing from the head all the elements that we use. | |
4471 | Normally this is only one; we use more than one element only if | |
4472 | TYPE is an aggregate and INIT is not a constructor. | |
4473 | ||
4474 | The arguments REQUIRE_CONSTANT and CONSTRUCTOR_CONSTANT request errors | |
4475 | if non-constant initializers or elements are seen. CONSTRUCTOR_CONSTANT | |
4476 | applies only to elements of constructors. | |
4477 | ||
d45cf215 RS |
4478 | If OFWHAT is nonnull, it specifies what we are initializing, for error |
4479 | messages. Examples: variable name, variable.member, array[44]. | |
4480 | If OFWHAT is null, the component name is stored on the spelling stack. */ | |
400fbf9f JW |
4481 | |
4482 | tree | |
4483 | digest_init (type, init, tail, require_constant, constructor_constant, ofwhat) | |
4484 | tree type, init, *tail; | |
4485 | int require_constant, constructor_constant; | |
4486 | char *ofwhat; | |
4487 | { | |
4488 | enum tree_code code = TREE_CODE (type); | |
4489 | tree element = 0; | |
4490 | tree old_tail_contents; | |
400fbf9f JW |
4491 | /* Nonzero if INIT is a braced grouping, which comes in as a CONSTRUCTOR |
4492 | tree node which has no TREE_TYPE. */ | |
4493 | int raw_constructor | |
4494 | = TREE_CODE (init) == CONSTRUCTOR && TREE_TYPE (init) == 0; | |
047de90b | 4495 | tree inside_init = init; |
400fbf9f JW |
4496 | |
4497 | /* By default, assume we use one element from a list. | |
4498 | We correct this later in the sole case where it is not true. */ | |
4499 | ||
4500 | if (tail) | |
4501 | { | |
4502 | old_tail_contents = *tail; | |
4503 | *tail = TREE_CHAIN (*tail); | |
4504 | } | |
4505 | ||
4506 | if (init == error_mark_node) | |
4507 | return init; | |
4508 | ||
4509 | /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */ | |
4510 | if (TREE_CODE (init) == NON_LVALUE_EXPR) | |
047de90b | 4511 | inside_init = TREE_OPERAND (init, 0); |
400fbf9f | 4512 | |
cdc54cc9 | 4513 | if (inside_init && raw_constructor |
047de90b RS |
4514 | && CONSTRUCTOR_ELTS (inside_init) != 0 |
4515 | && TREE_CHAIN (CONSTRUCTOR_ELTS (inside_init)) == 0) | |
400fbf9f | 4516 | { |
047de90b | 4517 | element = TREE_VALUE (CONSTRUCTOR_ELTS (inside_init)); |
400fbf9f JW |
4518 | /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */ |
4519 | if (element && TREE_CODE (element) == NON_LVALUE_EXPR) | |
4520 | element = TREE_OPERAND (element, 0); | |
4521 | } | |
4522 | ||
4523 | /* Initialization of an array of chars from a string constant | |
4524 | optionally enclosed in braces. */ | |
4525 | ||
4526 | if (code == ARRAY_TYPE) | |
4527 | { | |
4528 | tree typ1 = TYPE_MAIN_VARIANT (TREE_TYPE (type)); | |
4529 | if ((typ1 == char_type_node | |
4530 | || typ1 == signed_char_type_node | |
4531 | || typ1 == unsigned_char_type_node | |
4532 | || typ1 == unsigned_wchar_type_node | |
4533 | || typ1 == signed_wchar_type_node) | |
047de90b | 4534 | && ((inside_init && TREE_CODE (inside_init) == STRING_CST) |
400fbf9f JW |
4535 | || (element && TREE_CODE (element) == STRING_CST))) |
4536 | { | |
047de90b | 4537 | tree string = element ? element : inside_init; |
400fbf9f JW |
4538 | |
4539 | if ((TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (string))) | |
4540 | != char_type_node) | |
4541 | && TYPE_PRECISION (typ1) == TYPE_PRECISION (char_type_node)) | |
4542 | { | |
4543 | error_init ("char-array%s initialized from wide string", | |
4544 | " `%s'", ofwhat); | |
4545 | return error_mark_node; | |
4546 | } | |
4547 | if ((TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (string))) | |
4548 | == char_type_node) | |
4549 | && TYPE_PRECISION (typ1) != TYPE_PRECISION (char_type_node)) | |
4550 | { | |
4551 | error_init ("int-array%s initialized from non-wide string", | |
4552 | " `%s'", ofwhat); | |
4553 | return error_mark_node; | |
4554 | } | |
4555 | ||
4556 | TREE_TYPE (string) = type; | |
4557 | if (TYPE_DOMAIN (type) != 0 | |
4558 | && TREE_CODE (TYPE_SIZE (type)) == INTEGER_CST) | |
4559 | { | |
4560 | register int size = TREE_INT_CST_LOW (TYPE_SIZE (type)); | |
4561 | size = (size + BITS_PER_UNIT - 1) / BITS_PER_UNIT; | |
4562 | /* Subtract 1 because it's ok to ignore the terminating null char | |
4563 | that is counted in the length of the constant. */ | |
4564 | if (size < TREE_STRING_LENGTH (string) - 1) | |
4565 | pedwarn_init ( | |
4566 | "initializer-string for array of chars%s is too long", | |
4567 | " `%s'", ofwhat); | |
4568 | } | |
4569 | return string; | |
4570 | } | |
4571 | } | |
4572 | ||
4573 | /* Any type except an array can be initialized | |
4574 | from an expression of the same type, optionally with braces. | |
4575 | For an array, this is allowed only for a string constant. */ | |
4576 | ||
047de90b RS |
4577 | if (inside_init && (TREE_TYPE (inside_init) == type |
4578 | || (code == ARRAY_TYPE && TREE_TYPE (inside_init) | |
4579 | && comptypes (TREE_TYPE (inside_init), type)) | |
400fbf9f | 4580 | || (code == POINTER_TYPE |
047de90b RS |
4581 | && TREE_TYPE (inside_init) != 0 |
4582 | && (TREE_CODE (TREE_TYPE (inside_init)) == ARRAY_TYPE | |
4583 | || TREE_CODE (TREE_TYPE (inside_init)) == FUNCTION_TYPE) | |
4584 | && comptypes (TREE_TYPE (TREE_TYPE (inside_init)), | |
400fbf9f JW |
4585 | TREE_TYPE (type))))) |
4586 | { | |
4587 | if (code == POINTER_TYPE | |
047de90b RS |
4588 | && (TREE_CODE (TREE_TYPE (inside_init)) == ARRAY_TYPE |
4589 | || TREE_CODE (TREE_TYPE (inside_init)) == FUNCTION_TYPE)) | |
4590 | inside_init = default_conversion (inside_init); | |
4591 | else if (code == ARRAY_TYPE && TREE_CODE (inside_init) != STRING_CST) | |
400fbf9f JW |
4592 | { |
4593 | error_init ("array%s initialized from non-constant array expression", | |
4594 | " `%s'", ofwhat); | |
4595 | return error_mark_node; | |
4596 | } | |
4597 | ||
047de90b RS |
4598 | if (optimize && TREE_READONLY (inside_init) |
4599 | && TREE_CODE (inside_init) == VAR_DECL) | |
4600 | inside_init = decl_constant_value (inside_init); | |
400fbf9f | 4601 | |
047de90b | 4602 | if (require_constant && ! TREE_CONSTANT (inside_init)) |
400fbf9f JW |
4603 | { |
4604 | error_init ("initializer element%s is not constant", | |
4605 | " for `%s'", ofwhat); | |
047de90b | 4606 | inside_init = error_mark_node; |
400fbf9f | 4607 | } |
047de90b | 4608 | else if (require_constant && initializer_constant_valid_p (inside_init) == 0) |
400fbf9f JW |
4609 | { |
4610 | error_init ("initializer element%s is not computable at load time", | |
4611 | " for `%s'", ofwhat); | |
047de90b | 4612 | inside_init = error_mark_node; |
400fbf9f JW |
4613 | } |
4614 | ||
047de90b | 4615 | return inside_init; |
400fbf9f JW |
4616 | } |
4617 | ||
4618 | if (element && (TREE_TYPE (element) == type | |
4619 | || (code == ARRAY_TYPE && TREE_TYPE (element) | |
4620 | && comptypes (TREE_TYPE (element), type)))) | |
4621 | { | |
4622 | if (code == ARRAY_TYPE) | |
4623 | { | |
4624 | error_init ("array%s initialized from non-constant array expression", | |
4625 | " `%s'", ofwhat); | |
4626 | return error_mark_node; | |
4627 | } | |
4628 | if (pedantic && (code == RECORD_TYPE || code == UNION_TYPE)) | |
4629 | pedwarn ("single-expression nonscalar initializer has braces"); | |
4630 | if (optimize && TREE_READONLY (element) && TREE_CODE (element) == VAR_DECL) | |
4631 | element = decl_constant_value (element); | |
4632 | ||
4633 | if (require_constant && ! TREE_CONSTANT (element)) | |
4634 | { | |
4635 | error_init ("initializer element%s is not constant", | |
4636 | " for `%s'", ofwhat); | |
4637 | element = error_mark_node; | |
4638 | } | |
4639 | else if (require_constant && initializer_constant_valid_p (element) == 0) | |
4640 | { | |
4641 | error_init ("initializer element%s is not computable at load time", | |
4642 | " for `%s'", ofwhat); | |
4643 | element = error_mark_node; | |
4644 | } | |
4645 | ||
4646 | return element; | |
4647 | } | |
4648 | ||
4649 | /* Check for initializing a union by its first field. | |
4650 | Such an initializer must use braces. */ | |
4651 | ||
4652 | if (code == UNION_TYPE) | |
4653 | { | |
4654 | tree result; | |
4655 | tree field = TYPE_FIELDS (type); | |
4656 | ||
4657 | /* Find the first named field. ANSI decided in September 1990 | |
4658 | that only named fields count here. */ | |
4659 | while (field && DECL_NAME (field) == 0) | |
4660 | field = TREE_CHAIN (field); | |
4661 | ||
4662 | if (field == 0) | |
4663 | { | |
4664 | error_init ("union%s with no named members cannot be initialized", | |
4665 | " `%s'", ofwhat); | |
4666 | return error_mark_node; | |
4667 | } | |
4668 | ||
805f961c RS |
4669 | if (raw_constructor) |
4670 | result = process_init_constructor (type, inside_init, 0, | |
4671 | require_constant, | |
4672 | constructor_constant, ofwhat); | |
4673 | else if (tail != 0) | |
4674 | { | |
4675 | *tail = old_tail_contents; | |
4676 | result = process_init_constructor (type, 0, tail, | |
4677 | require_constant, | |
4678 | constructor_constant, ofwhat); | |
4679 | } | |
4680 | else | |
4681 | result = 0; | |
400fbf9f | 4682 | |
d45cf215 RS |
4683 | if (result) |
4684 | return result; | |
400fbf9f JW |
4685 | } |
4686 | ||
4687 | /* Handle scalar types, including conversions. */ | |
4688 | ||
4689 | if (code == INTEGER_TYPE || code == REAL_TYPE || code == POINTER_TYPE | |
4690 | || code == ENUMERAL_TYPE) | |
4691 | { | |
4692 | if (raw_constructor) | |
4693 | { | |
4694 | if (element == 0) | |
4695 | { | |
4696 | error_init ( | |
4697 | "initializer for scalar%s requires one element", | |
4698 | " `%s'", ofwhat); | |
4699 | return error_mark_node; | |
4700 | } | |
047de90b | 4701 | inside_init = element; |
400fbf9f JW |
4702 | } |
4703 | ||
4704 | #if 0 /* A non-raw constructor is an actual expression. */ | |
047de90b | 4705 | if (TREE_CODE (inside_init) == CONSTRUCTOR) |
400fbf9f JW |
4706 | { |
4707 | error_init ("initializer for scalar%s has extra braces", | |
4708 | " `%s'", ofwhat); | |
4709 | return error_mark_node; | |
4710 | } | |
4711 | #endif | |
4712 | ||
d45cf215 RS |
4713 | SAVE_SPELLING_DEPTH |
4714 | ({ | |
4715 | if (ofwhat) | |
4716 | push_string (ofwhat); | |
cdc54cc9 TW |
4717 | inside_init |
4718 | = convert_for_assignment (type, | |
4719 | default_conversion (raw_constructor | |
4720 | ? inside_init | |
4721 | : init), | |
4722 | &initialization_message, NULL_TREE, 0); | |
d45cf215 | 4723 | }); |
400fbf9f | 4724 | |
047de90b | 4725 | if (require_constant && ! TREE_CONSTANT (inside_init)) |
400fbf9f JW |
4726 | { |
4727 | error_init ("initializer element%s is not constant", | |
4728 | " for `%s'", ofwhat); | |
047de90b | 4729 | inside_init = error_mark_node; |
400fbf9f | 4730 | } |
047de90b | 4731 | else if (require_constant && initializer_constant_valid_p (inside_init) == 0) |
400fbf9f JW |
4732 | { |
4733 | error_init ("initializer element%s is not computable at load time", | |
4734 | " for `%s'", ofwhat); | |
047de90b | 4735 | inside_init = error_mark_node; |
400fbf9f JW |
4736 | } |
4737 | ||
047de90b | 4738 | return inside_init; |
400fbf9f JW |
4739 | } |
4740 | ||
4741 | /* Come here only for records and arrays. */ | |
4742 | ||
4743 | if (TYPE_SIZE (type) && TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST) | |
4744 | { | |
4745 | error_init ("variable-sized object%s may not be initialized", | |
4746 | " `%s'", ofwhat); | |
4747 | return error_mark_node; | |
4748 | } | |
4749 | ||
4750 | if (code == ARRAY_TYPE || code == RECORD_TYPE) | |
4751 | { | |
4752 | if (raw_constructor) | |
047de90b RS |
4753 | return process_init_constructor (type, inside_init, |
4754 | 0, constructor_constant, | |
400fbf9f JW |
4755 | constructor_constant, ofwhat); |
4756 | else if (tail != 0) | |
4757 | { | |
4758 | *tail = old_tail_contents; | |
4759 | return process_init_constructor (type, 0, tail, constructor_constant, | |
4760 | constructor_constant, ofwhat); | |
4761 | } | |
4762 | else if (flag_traditional) | |
4763 | /* Traditionally one can say `char x[100] = 0;'. */ | |
4764 | return process_init_constructor (type, | |
4765 | build_nt (CONSTRUCTOR, 0, | |
047de90b | 4766 | tree_cons (0, inside_init, 0)), |
400fbf9f JW |
4767 | 0, constructor_constant, |
4768 | constructor_constant, ofwhat); | |
4769 | } | |
4770 | ||
4771 | error_init ("invalid initializer%s", " for `%s'", ofwhat); | |
4772 | return error_mark_node; | |
4773 | } | |
4774 | \f | |
4775 | /* Process a constructor for a variable of type TYPE. | |
4776 | The constructor elements may be specified either with INIT or with ELTS, | |
4777 | only one of which should be non-null. | |
4778 | ||
4779 | If INIT is specified, it is a CONSTRUCTOR node which is specifically | |
4780 | and solely for initializing this datum. | |
4781 | ||
4782 | If ELTS is specified, it is the address of a variable containing | |
4783 | a list of expressions. We take as many elements as we need | |
4784 | from the head of the list and update the list. | |
4785 | ||
4786 | In the resulting constructor, TREE_CONSTANT is set if all elts are | |
4787 | constant, and TREE_STATIC is set if, in addition, all elts are simple enough | |
4788 | constants that the assembler and linker can compute them. | |
4789 | ||
4790 | The argument CONSTANT_VALUE says to print an error if either the | |
4791 | value or any element is not a constant. | |
4792 | ||
4793 | The argument CONSTANT_ELEMENT says to print an error if an element | |
4794 | of an aggregate is not constant. It does not apply to a value | |
4795 | which is not a constructor. | |
4796 | ||
4797 | OFWHAT is a character string describing the object being initialized, | |
4798 | for error messages. It might be "variable" or "variable.member" | |
d45cf215 RS |
4799 | or "variable[17].member[5]". If OFWHAT is null, the description string |
4800 | is stored on the spelling stack. */ | |
400fbf9f JW |
4801 | |
4802 | static tree | |
4803 | process_init_constructor (type, init, elts, constant_value, constant_element, | |
4804 | ofwhat) | |
4805 | tree type, init, *elts; | |
4806 | int constant_value, constant_element; | |
4807 | char *ofwhat; | |
4808 | { | |
4809 | register tree tail; | |
4810 | /* List of the elements of the result constructor, | |
4811 | in reverse order. */ | |
4812 | register tree members = NULL; | |
400fbf9f JW |
4813 | tree result; |
4814 | int allconstant = 1; | |
4815 | int allsimple = 1; | |
4816 | int erroneous = 0; | |
d45cf215 RS |
4817 | int depth = SPELLING_DEPTH (); |
4818 | ||
4819 | if (ofwhat) | |
4820 | push_string (ofwhat); | |
400fbf9f JW |
4821 | |
4822 | /* Make TAIL be the list of elements to use for the initialization, | |
4823 | no matter how the data was given to us. */ | |
4824 | ||
4825 | if (elts) | |
4826 | tail = *elts; | |
4827 | else | |
4828 | tail = CONSTRUCTOR_ELTS (init); | |
4829 | ||
4830 | /* Gobble as many elements as needed, and make a constructor or initial value | |
4831 | for each element of this aggregate. Chain them together in result. | |
4832 | If there are too few, use 0 for each scalar ultimate component. */ | |
4833 | ||
4834 | if (TREE_CODE (type) == ARRAY_TYPE) | |
4835 | { | |
d45cf215 RS |
4836 | tree min_index, max_index, current_index, members_index; |
4837 | tree bound_type; | |
4838 | tree one; | |
4839 | ||
4840 | /* If we have array bounds, set our bounds from that. Otherwise, | |
4841 | we have a lower bound of zero and an unknown upper bound. Also | |
4842 | set the type of the bounds; use "int" as default. */ | |
4843 | if (TYPE_DOMAIN (type)) | |
4844 | { | |
4845 | min_index = members_index = TYPE_MIN_VALUE (TYPE_DOMAIN (type)); | |
4846 | max_index = TYPE_MAX_VALUE (TYPE_DOMAIN (type)); | |
4847 | bound_type = TREE_TYPE (min_index); | |
4848 | } | |
400fbf9f | 4849 | else |
d45cf215 RS |
4850 | { |
4851 | min_index = members_index = integer_zero_node; | |
4852 | max_index = 0; | |
4853 | bound_type = integer_type_node; | |
4854 | } | |
4855 | ||
4856 | one = convert (bound_type, integer_one_node); | |
400fbf9f | 4857 | |
d45cf215 RS |
4858 | /* Don't leave the loop based on index if the next item has an explicit |
4859 | index value that will override it. */ | |
400fbf9f | 4860 | |
d45cf215 RS |
4861 | for (current_index = min_index; tail != 0; |
4862 | current_index = fold (build (PLUS_EXPR, bound_type, | |
4863 | current_index, one))) | |
400fbf9f JW |
4864 | { |
4865 | register tree next1; | |
4866 | ||
4867 | /* If this element specifies an index, | |
4868 | move to that index before storing it in the new list. */ | |
4869 | if (TREE_PURPOSE (tail) != 0) | |
4870 | { | |
4871 | int win = 0; | |
5a7ec9d9 | 4872 | tree index = TREE_PURPOSE (tail); |
400fbf9f | 4873 | |
5a7ec9d9 RS |
4874 | if (index && TREE_CODE (index) == NON_LVALUE_EXPR) |
4875 | index = TREE_OPERAND (index, 0); | |
4876 | ||
4877 | if (TREE_CODE (index) == IDENTIFIER_NODE) | |
400fbf9f | 4878 | error ("field name used as index in array initializer"); |
5a7ec9d9 | 4879 | else if (TREE_CODE (index) != INTEGER_CST) |
400fbf9f | 4880 | error ("non-constant array index in initializer"); |
5a7ec9d9 RS |
4881 | else if (tree_int_cst_lt (index, min_index) |
4882 | || (max_index && tree_int_cst_lt (max_index, index))) | |
400fbf9f JW |
4883 | error ("array index out of range in initializer"); |
4884 | else | |
5a7ec9d9 | 4885 | current_index = index, win = 1; |
400fbf9f JW |
4886 | |
4887 | if (!win) | |
4888 | TREE_VALUE (tail) = error_mark_node; | |
4889 | } | |
4890 | ||
d45cf215 | 4891 | if (max_index && tree_int_cst_lt (max_index, current_index)) |
400fbf9f JW |
4892 | break; /* Stop if we've indeed run out of elements. */ |
4893 | ||
4894 | /* Now digest the value specified. */ | |
4895 | if (TREE_VALUE (tail) != 0) | |
4896 | { | |
4897 | tree tail1 = tail; | |
4898 | ||
d45cf215 RS |
4899 | /* Build the element of this array, with "[]" notation. For |
4900 | error messages, we assume that the index fits within a | |
4901 | host int. */ | |
4902 | SAVE_SPELLING_DEPTH | |
4903 | ({ | |
4904 | push_array_bounds (TREE_INT_CST_LOW (current_index)); | |
4905 | next1 = digest_init (TYPE_MAIN_VARIANT (TREE_TYPE (type)), | |
4906 | TREE_VALUE (tail), &tail1, | |
4907 | /* Both of these are the same because | |
4908 | a value here is an elt overall. */ | |
4909 | constant_element, constant_element, 0); | |
4910 | }); | |
400fbf9f JW |
4911 | |
4912 | if (tail1 != 0 && TREE_CODE (tail1) != TREE_LIST) | |
4913 | abort (); | |
d45cf215 | 4914 | if (tail == tail1 && TYPE_DOMAIN (type) == 0) |
400fbf9f JW |
4915 | { |
4916 | error_init ( | |
4917 | "non-empty initializer for array%s of empty elements", | |
d45cf215 | 4918 | " `%s'", 0); |
400fbf9f JW |
4919 | /* Just ignore what we were supposed to use. */ |
4920 | tail1 = 0; | |
4921 | } | |
4922 | tail = tail1; | |
4923 | } | |
4924 | else | |
4925 | { | |
4926 | next1 = error_mark_node; | |
4927 | tail = TREE_CHAIN (tail); | |
4928 | } | |
4929 | ||
4930 | if (next1 == error_mark_node) | |
4931 | erroneous = 1; | |
4932 | else if (!TREE_CONSTANT (next1)) | |
4933 | allconstant = 0; | |
4934 | else if (initializer_constant_valid_p (next1) == 0) | |
4935 | allsimple = 0; | |
4936 | ||
4937 | /* Now store NEXT1 in the list, I elements from the *end*. | |
4938 | Make the list longer if necessary. */ | |
d45cf215 | 4939 | while (! tree_int_cst_lt (current_index, members_index)) |
400fbf9f JW |
4940 | { |
4941 | members = tree_cons (NULL_TREE, NULL_TREE, members); | |
d45cf215 RS |
4942 | members_index = fold (build (PLUS_EXPR, bound_type, |
4943 | members_index, one)); | |
400fbf9f | 4944 | } |
d45cf215 | 4945 | |
400fbf9f JW |
4946 | { |
4947 | tree temp; | |
d45cf215 | 4948 | tree idx; |
400fbf9f JW |
4949 | |
4950 | temp = members; | |
d45cf215 RS |
4951 | for (idx = fold (build (MINUS_EXPR, bound_type, |
4952 | members_index, one)); | |
4953 | tree_int_cst_lt (current_index, idx); | |
4954 | idx = fold (build (MINUS_EXPR, bound_type, idx, one))) | |
400fbf9f JW |
4955 | temp = TREE_CHAIN (temp); |
4956 | TREE_VALUE (temp) = next1; | |
4957 | } | |
4958 | } | |
4959 | } | |
4960 | if (TREE_CODE (type) == RECORD_TYPE) | |
4961 | { | |
4962 | register tree field; | |
d45cf215 | 4963 | int members_length = 0; |
400fbf9f JW |
4964 | int i; |
4965 | ||
4966 | /* Don't leave the loop based on field just yet; see if next item | |
4967 | overrides the expected field first. */ | |
4968 | ||
4969 | for (field = TYPE_FIELDS (type), i = 0; tail; | |
4970 | field = TREE_CHAIN (field), i++) | |
4971 | { | |
4972 | register tree next1; | |
4973 | ||
4974 | /* If this element specifies a field, | |
4975 | move to that field before storing it in the new list. */ | |
4976 | if (TREE_PURPOSE (tail) != 0) | |
4977 | { | |
4978 | int win = 0; | |
4979 | ||
4980 | if (TREE_CODE (TREE_PURPOSE (tail)) != IDENTIFIER_NODE) | |
4981 | error ("index value instead of field name in structure initializer"); | |
4982 | else | |
4983 | { | |
4984 | tree temp; | |
4985 | int j; | |
4986 | for (temp = TYPE_FIELDS (type), j = 0; | |
4987 | temp; | |
4988 | temp = TREE_CHAIN (temp), j++) | |
4989 | if (DECL_NAME (temp) == TREE_PURPOSE (tail)) | |
4990 | break; | |
4991 | if (temp) | |
4992 | field = temp, i = j, win = 1; | |
4993 | else | |
805f961c RS |
4994 | error ("no field `%s' in structure being initialized", |
4995 | IDENTIFIER_POINTER (TREE_PURPOSE (tail))); | |
400fbf9f JW |
4996 | } |
4997 | if (!win) | |
4998 | TREE_VALUE (tail) = error_mark_node; | |
4999 | } | |
5000 | ||
5001 | if (field == 0) | |
5002 | break; /* No more fields to init. */ | |
5003 | ||
5004 | if (! DECL_NAME (field)) | |
5005 | { | |
5006 | next1 = integer_zero_node; | |
5007 | } | |
5008 | else if (TREE_VALUE (tail) != 0) | |
5009 | { | |
5010 | tree tail1 = tail; | |
5011 | ||
5012 | /* Build the name of this member, with a "." for membership. */ | |
d45cf215 RS |
5013 | SAVE_SPELLING_DEPTH |
5014 | ({ | |
5015 | push_member_name (IDENTIFIER_POINTER (DECL_NAME (field))); | |
5016 | next1 = digest_init (TREE_TYPE (field), | |
5017 | TREE_VALUE (tail), &tail1, | |
5018 | constant_element, constant_element, 0); | |
5019 | }); | |
400fbf9f JW |
5020 | if (tail1 != 0 && TREE_CODE (tail1) != TREE_LIST) |
5021 | abort (); | |
5022 | tail = tail1; | |
5023 | } | |
5024 | else | |
5025 | { | |
5026 | next1 = error_mark_node; | |
5027 | tail = TREE_CHAIN (tail); | |
5028 | } | |
5029 | ||
5030 | if (next1 == error_mark_node) | |
5031 | erroneous = 1; | |
5032 | else if (!TREE_CONSTANT (next1)) | |
5033 | allconstant = 0; | |
5034 | else if (initializer_constant_valid_p (next1) == 0) | |
5035 | allsimple = 0; | |
5036 | ||
5037 | /* Now store NEXT1 in the list, I elements from the *end*. | |
5038 | Make the list longer if necessary. */ | |
5039 | while (i >= members_length) | |
5040 | { | |
5041 | members = tree_cons (NULL_TREE, NULL_TREE, members); | |
5042 | members_length++; | |
5043 | } | |
5044 | { | |
5045 | tree temp; | |
5046 | int j; | |
5047 | ||
5048 | temp = members; | |
5049 | for (j = members_length - 1; j > i; j--) | |
5050 | temp = TREE_CHAIN (temp); | |
5051 | TREE_VALUE (temp) = next1; | |
5052 | TREE_PURPOSE (temp) = field; | |
5053 | } | |
5054 | } | |
5055 | } | |
5056 | if (TREE_CODE (type) == UNION_TYPE) | |
5057 | { | |
5058 | register tree field = TYPE_FIELDS (type); | |
5059 | register tree next1; | |
5060 | ||
5061 | /* Find the first named field. ANSI decided in September 1990 | |
5062 | that only named fields count here. */ | |
5063 | while (field && DECL_NAME (field) == 0) | |
5064 | field = TREE_CHAIN (field); | |
5065 | ||
5066 | /* For a union, get the initializer for 1 fld. */ | |
5067 | ||
5068 | /* If this element specifies a field, initialize via that field. */ | |
5069 | if (TREE_PURPOSE (tail) != 0) | |
5070 | { | |
5071 | int win = 0; | |
5072 | ||
805f961c RS |
5073 | if (TREE_CODE (TREE_PURPOSE (tail)) == FIELD_DECL) |
5074 | /* Handle the case of a call by build_c_cast. */ | |
5075 | field = TREE_PURPOSE (tail), win = 1; | |
5076 | else if (TREE_CODE (TREE_PURPOSE (tail)) != IDENTIFIER_NODE) | |
400fbf9f JW |
5077 | error ("index value instead of field name in union initializer"); |
5078 | else | |
5079 | { | |
5080 | tree temp; | |
5081 | for (temp = TYPE_FIELDS (type); | |
5082 | temp; | |
5083 | temp = TREE_CHAIN (temp)) | |
5084 | if (DECL_NAME (temp) == TREE_PURPOSE (tail)) | |
5085 | break; | |
5086 | if (temp) | |
5087 | field = temp, win = 1; | |
5088 | else | |
805f961c RS |
5089 | error ("no field `%s' in union being initialized", |
5090 | IDENTIFIER_POINTER (TREE_PURPOSE (tail))); | |
400fbf9f JW |
5091 | } |
5092 | if (!win) | |
5093 | TREE_VALUE (tail) = error_mark_node; | |
5094 | } | |
5095 | ||
5096 | if (TREE_VALUE (tail) != 0) | |
5097 | { | |
5098 | tree tail1 = tail; | |
5099 | ||
5100 | /* Build the name of this member, with a "." for membership. */ | |
d45cf215 RS |
5101 | SAVE_SPELLING_DEPTH |
5102 | ({ | |
5103 | push_member_name (IDENTIFIER_POINTER (DECL_NAME (field))); | |
5104 | next1 = digest_init (TREE_TYPE (field), | |
5105 | TREE_VALUE (tail), &tail1, | |
5106 | constant_value, constant_element, 0); | |
5107 | }); | |
400fbf9f JW |
5108 | if (tail1 != 0 && TREE_CODE (tail1) != TREE_LIST) |
5109 | abort (); | |
5110 | tail = tail1; | |
5111 | } | |
5112 | else | |
5113 | { | |
5114 | next1 = error_mark_node; | |
5115 | tail = TREE_CHAIN (tail); | |
5116 | } | |
5117 | ||
5118 | if (next1 == error_mark_node) | |
5119 | erroneous = 1; | |
5120 | else if (!TREE_CONSTANT (next1)) | |
5121 | allconstant = 0; | |
5122 | else if (initializer_constant_valid_p (next1) == 0) | |
5123 | allsimple = 0; | |
5124 | members = tree_cons (field, next1, members); | |
5125 | } | |
5126 | ||
5127 | /* If arguments were specified as a list, just remove the ones we used. */ | |
5128 | if (elts) | |
5129 | *elts = tail; | |
5130 | /* If arguments were specified as a constructor, | |
5131 | complain unless we used all the elements of the constructor. */ | |
5132 | else if (tail) | |
5133 | { | |
5134 | if (TREE_CODE (type) == UNION_TYPE) | |
5135 | { | |
5136 | pedwarn_init ("excess elements in union initializer%s", | |
d45cf215 | 5137 | " after `%s'", 0); |
400fbf9f JW |
5138 | } |
5139 | else | |
5140 | { | |
5141 | pedwarn_init ("excess elements in aggregate initializer%s", | |
d45cf215 | 5142 | " after `%s'", 0); |
400fbf9f JW |
5143 | } |
5144 | } | |
5145 | ||
d45cf215 RS |
5146 | /* It might be possible to use SAVE_SPELLING_DEPTH, but I suspect that |
5147 | some preprocessor somewhere won't accept that much text as an argument. | |
5148 | It's also likely to make debugging difficult. */ | |
5149 | ||
5150 | RESTORE_SPELLING_DEPTH (depth); | |
5151 | ||
400fbf9f JW |
5152 | if (erroneous) |
5153 | return error_mark_node; | |
5154 | ||
5155 | result = build (CONSTRUCTOR, type, NULL_TREE, nreverse (members)); | |
5156 | if (allconstant) TREE_CONSTANT (result) = 1; | |
5157 | if (allconstant && allsimple) TREE_STATIC (result) = 1; | |
5158 | return result; | |
5159 | } | |
5160 | \f | |
5161 | /* Expand an ASM statement with operands, handling output operands | |
5162 | that are not variables or INDIRECT_REFS by transforming such | |
5163 | cases into cases that expand_asm_operands can handle. | |
5164 | ||
5165 | Arguments are same as for expand_asm_operands. */ | |
5166 | ||
5167 | void | |
5168 | c_expand_asm_operands (string, outputs, inputs, clobbers, vol, filename, line) | |
5169 | tree string, outputs, inputs, clobbers; | |
5170 | int vol; | |
5171 | char *filename; | |
5172 | int line; | |
5173 | { | |
5174 | int noutputs = list_length (outputs); | |
5175 | register int i; | |
5176 | /* o[I] is the place that output number I should be written. */ | |
5177 | register tree *o = (tree *) alloca (noutputs * sizeof (tree)); | |
5178 | register tree tail; | |
5179 | ||
5180 | if (TREE_CODE (string) == ADDR_EXPR) | |
5181 | string = TREE_OPERAND (string, 0); | |
5182 | if (TREE_CODE (string) != STRING_CST) | |
5183 | { | |
5184 | error ("asm template is not a string constant"); | |
5185 | return; | |
5186 | } | |
5187 | ||
7b6327ae | 5188 | /* Record the contents of OUTPUTS before it is modified. */ |
400fbf9f JW |
5189 | for (i = 0, tail = outputs; tail; tail = TREE_CHAIN (tail), i++) |
5190 | o[i] = TREE_VALUE (tail); | |
5191 | ||
5192 | /* Perform default conversions on array and function inputs. */ | |
5193 | /* Don't do this for other types-- | |
5194 | it would screw up operands expected to be in memory. */ | |
5195 | for (i = 0, tail = inputs; tail; tail = TREE_CHAIN (tail), i++) | |
5196 | if (TREE_CODE (TREE_TYPE (TREE_VALUE (tail))) == ARRAY_TYPE | |
5197 | || TREE_CODE (TREE_TYPE (TREE_VALUE (tail))) == FUNCTION_TYPE) | |
5198 | TREE_VALUE (tail) = default_conversion (TREE_VALUE (tail)); | |
5199 | ||
5200 | /* Generate the ASM_OPERANDS insn; | |
5201 | store into the TREE_VALUEs of OUTPUTS some trees for | |
5202 | where the values were actually stored. */ | |
5203 | expand_asm_operands (string, outputs, inputs, clobbers, vol, filename, line); | |
5204 | ||
5205 | /* Copy all the intermediate outputs into the specified outputs. */ | |
5206 | for (i = 0, tail = outputs; tail; tail = TREE_CHAIN (tail), i++) | |
5207 | { | |
5208 | if (o[i] != TREE_VALUE (tail)) | |
5209 | { | |
5210 | expand_expr (build_modify_expr (o[i], NOP_EXPR, TREE_VALUE (tail)), | |
5211 | 0, VOIDmode, 0); | |
5212 | free_temp_slots (); | |
5213 | } | |
5214 | /* Detect modification of read-only values. | |
5215 | (Otherwise done by build_modify_expr.) */ | |
5216 | else | |
5217 | { | |
5218 | tree type = TREE_TYPE (o[i]); | |
5219 | if (TYPE_READONLY (type) | |
5220 | || ((TREE_CODE (type) == RECORD_TYPE | |
5221 | || TREE_CODE (type) == UNION_TYPE) | |
5222 | && C_TYPE_FIELDS_READONLY (type))) | |
5223 | readonly_warning (o[i], "modification by `asm'"); | |
5224 | } | |
5225 | } | |
5226 | ||
5227 | /* Those MODIFY_EXPRs could do autoincrements. */ | |
5228 | emit_queue (); | |
5229 | } | |
5230 | \f | |
5231 | /* Expand a C `return' statement. | |
5232 | RETVAL is the expression for what to return, | |
5233 | or a null pointer for `return;' with no value. */ | |
5234 | ||
5235 | void | |
5236 | c_expand_return (retval) | |
5237 | tree retval; | |
5238 | { | |
5239 | tree valtype = TREE_TYPE (TREE_TYPE (current_function_decl)); | |
5240 | ||
5241 | if (TREE_THIS_VOLATILE (current_function_decl)) | |
5242 | warning ("function declared `volatile' has a `return' statement"); | |
5243 | ||
5244 | if (!retval) | |
5245 | { | |
5246 | current_function_returns_null = 1; | |
5247 | if (warn_return_type && valtype != 0 && TREE_CODE (valtype) != VOID_TYPE) | |
5248 | warning ("`return' with no value, in function returning non-void"); | |
5249 | expand_null_return (); | |
5250 | } | |
5251 | else if (valtype == 0 || TREE_CODE (valtype) == VOID_TYPE) | |
5252 | { | |
5253 | current_function_returns_null = 1; | |
5254 | if (pedantic || TREE_CODE (TREE_TYPE (retval)) != VOID_TYPE) | |
5255 | pedwarn ("`return' with a value, in function returning void"); | |
5256 | expand_return (retval); | |
5257 | } | |
5258 | else | |
5259 | { | |
5260 | tree t = convert_for_assignment (valtype, retval, "return", | |
5261 | NULL_TREE, 0); | |
5262 | tree res = DECL_RESULT (current_function_decl); | |
5263 | t = build (MODIFY_EXPR, TREE_TYPE (res), | |
5264 | res, convert (TREE_TYPE (res), t)); | |
5265 | expand_return (t); | |
5266 | current_function_returns_value = 1; | |
5267 | } | |
5268 | } | |
5269 | \f | |
5270 | /* Start a C switch statement, testing expression EXP. | |
5271 | Return EXP if it is valid, an error node otherwise. */ | |
5272 | ||
5273 | tree | |
5274 | c_expand_start_case (exp) | |
5275 | tree exp; | |
5276 | { | |
5277 | register enum tree_code code = TREE_CODE (TREE_TYPE (exp)); | |
5278 | tree type = TREE_TYPE (exp); | |
5279 | ||
5280 | if (code != INTEGER_TYPE && code != ENUMERAL_TYPE && code != ERROR_MARK) | |
5281 | { | |
5282 | error ("switch quantity not an integer"); | |
5283 | exp = error_mark_node; | |
5284 | } | |
5285 | else | |
5286 | { | |
5287 | tree index; | |
5288 | ||
5289 | if (warn_traditional | |
5290 | && (TREE_TYPE (exp) == long_integer_type_node | |
5291 | || TREE_TYPE (exp) == long_unsigned_type_node)) | |
5292 | pedwarn ("`long' switch expression not converted to `int' in ANSI C"); | |
5293 | ||
5294 | exp = default_conversion (exp); | |
5295 | type = TREE_TYPE (exp); | |
5296 | index = get_unwidened (exp, 0); | |
5297 | /* We can't strip a conversion from a signed type to an unsigned, | |
5298 | because if we did, int_fits_type_p would do the wrong thing | |
5299 | when checking case values for being in range, | |
5300 | and it's too hard to do the right thing. */ | |
5301 | if (TREE_UNSIGNED (TREE_TYPE (exp)) | |
5302 | == TREE_UNSIGNED (TREE_TYPE (index))) | |
5303 | exp = index; | |
5304 | } | |
5305 | ||
5306 | expand_start_case (1, exp, type, "switch statement"); | |
5307 | ||
5308 | return exp; | |
5309 | } |