gdb:
[deliverable/binutils-gdb.git] / gdb / valops.c
1 /* Perform non-arithmetic operations on values, for GDB.
2
3 Copyright (C) 1986, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995,
4 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007,
5 2008, 2009, 2010 Free Software Foundation, Inc.
6
7 This file is part of GDB.
8
9 This program is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 3 of the License, or
12 (at your option) any later version.
13
14 This program is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
18
19 You should have received a copy of the GNU General Public License
20 along with this program. If not, see <http://www.gnu.org/licenses/>. */
21
22 #include "defs.h"
23 #include "symtab.h"
24 #include "gdbtypes.h"
25 #include "value.h"
26 #include "frame.h"
27 #include "inferior.h"
28 #include "gdbcore.h"
29 #include "target.h"
30 #include "demangle.h"
31 #include "language.h"
32 #include "gdbcmd.h"
33 #include "regcache.h"
34 #include "cp-abi.h"
35 #include "block.h"
36 #include "infcall.h"
37 #include "dictionary.h"
38 #include "cp-support.h"
39 #include "dfp.h"
40 #include "user-regs.h"
41
42 #include <errno.h>
43 #include "gdb_string.h"
44 #include "gdb_assert.h"
45 #include "cp-support.h"
46 #include "observer.h"
47 #include "objfiles.h"
48 #include "symtab.h"
49
50 extern int overload_debug;
51 /* Local functions. */
52
53 static int typecmp (int staticp, int varargs, int nargs,
54 struct field t1[], struct value *t2[]);
55
56 static struct value *search_struct_field (const char *, struct value *,
57 int, struct type *, int);
58
59 static struct value *search_struct_method (const char *, struct value **,
60 struct value **,
61 int, int *, struct type *);
62
63 static int find_oload_champ_namespace (struct type **, int,
64 const char *, const char *,
65 struct symbol ***,
66 struct badness_vector **,
67 const int no_adl);
68
69 static
70 int find_oload_champ_namespace_loop (struct type **, int,
71 const char *, const char *,
72 int, struct symbol ***,
73 struct badness_vector **, int *,
74 const int no_adl);
75
76 static int find_oload_champ (struct type **, int, int, int,
77 struct fn_field *, struct symbol **,
78 struct badness_vector **);
79
80 static int oload_method_static (int, struct fn_field *, int);
81
82 enum oload_classification { STANDARD, NON_STANDARD, INCOMPATIBLE };
83
84 static enum
85 oload_classification classify_oload_match (struct badness_vector *,
86 int, int);
87
88 static struct value *value_struct_elt_for_reference (struct type *,
89 int, struct type *,
90 char *,
91 struct type *,
92 int, enum noside);
93
94 static struct value *value_namespace_elt (const struct type *,
95 char *, int , enum noside);
96
97 static struct value *value_maybe_namespace_elt (const struct type *,
98 char *, int,
99 enum noside);
100
101 static CORE_ADDR allocate_space_in_inferior (int);
102
103 static struct value *cast_into_complex (struct type *, struct value *);
104
105 static struct fn_field *find_method_list (struct value **, const char *,
106 int, struct type *, int *,
107 struct type **, int *);
108
109 void _initialize_valops (void);
110
111 #if 0
112 /* Flag for whether we want to abandon failed expression evals by
113 default. */
114
115 static int auto_abandon = 0;
116 #endif
117
118 int overload_resolution = 0;
119 static void
120 show_overload_resolution (struct ui_file *file, int from_tty,
121 struct cmd_list_element *c,
122 const char *value)
123 {
124 fprintf_filtered (file, _("\
125 Overload resolution in evaluating C++ functions is %s.\n"),
126 value);
127 }
128
129 /* Find the address of function name NAME in the inferior. If OBJF_P
130 is non-NULL, *OBJF_P will be set to the OBJFILE where the function
131 is defined. */
132
133 struct value *
134 find_function_in_inferior (const char *name, struct objfile **objf_p)
135 {
136 struct symbol *sym;
137
138 sym = lookup_symbol (name, 0, VAR_DOMAIN, 0);
139 if (sym != NULL)
140 {
141 if (SYMBOL_CLASS (sym) != LOC_BLOCK)
142 {
143 error (_("\"%s\" exists in this program but is not a function."),
144 name);
145 }
146
147 if (objf_p)
148 *objf_p = SYMBOL_SYMTAB (sym)->objfile;
149
150 return value_of_variable (sym, NULL);
151 }
152 else
153 {
154 struct minimal_symbol *msymbol =
155 lookup_minimal_symbol (name, NULL, NULL);
156
157 if (msymbol != NULL)
158 {
159 struct objfile *objfile = msymbol_objfile (msymbol);
160 struct gdbarch *gdbarch = get_objfile_arch (objfile);
161
162 struct type *type;
163 CORE_ADDR maddr;
164 type = lookup_pointer_type (builtin_type (gdbarch)->builtin_char);
165 type = lookup_function_type (type);
166 type = lookup_pointer_type (type);
167 maddr = SYMBOL_VALUE_ADDRESS (msymbol);
168
169 if (objf_p)
170 *objf_p = objfile;
171
172 return value_from_pointer (type, maddr);
173 }
174 else
175 {
176 if (!target_has_execution)
177 error (_("evaluation of this expression requires the target program to be active"));
178 else
179 error (_("evaluation of this expression requires the program to have a function \"%s\"."), name);
180 }
181 }
182 }
183
184 /* Allocate NBYTES of space in the inferior using the inferior's
185 malloc and return a value that is a pointer to the allocated
186 space. */
187
188 struct value *
189 value_allocate_space_in_inferior (int len)
190 {
191 struct objfile *objf;
192 struct value *val = find_function_in_inferior ("malloc", &objf);
193 struct gdbarch *gdbarch = get_objfile_arch (objf);
194 struct value *blocklen;
195
196 blocklen = value_from_longest (builtin_type (gdbarch)->builtin_int, len);
197 val = call_function_by_hand (val, 1, &blocklen);
198 if (value_logical_not (val))
199 {
200 if (!target_has_execution)
201 error (_("No memory available to program now: you need to start the target first"));
202 else
203 error (_("No memory available to program: call to malloc failed"));
204 }
205 return val;
206 }
207
208 static CORE_ADDR
209 allocate_space_in_inferior (int len)
210 {
211 return value_as_long (value_allocate_space_in_inferior (len));
212 }
213
214 /* Cast struct value VAL to type TYPE and return as a value.
215 Both type and val must be of TYPE_CODE_STRUCT or TYPE_CODE_UNION
216 for this to work. Typedef to one of the codes is permitted.
217 Returns NULL if the cast is neither an upcast nor a downcast. */
218
219 static struct value *
220 value_cast_structs (struct type *type, struct value *v2)
221 {
222 struct type *t1;
223 struct type *t2;
224 struct value *v;
225
226 gdb_assert (type != NULL && v2 != NULL);
227
228 t1 = check_typedef (type);
229 t2 = check_typedef (value_type (v2));
230
231 /* Check preconditions. */
232 gdb_assert ((TYPE_CODE (t1) == TYPE_CODE_STRUCT
233 || TYPE_CODE (t1) == TYPE_CODE_UNION)
234 && !!"Precondition is that type is of STRUCT or UNION kind.");
235 gdb_assert ((TYPE_CODE (t2) == TYPE_CODE_STRUCT
236 || TYPE_CODE (t2) == TYPE_CODE_UNION)
237 && !!"Precondition is that value is of STRUCT or UNION kind");
238
239 if (TYPE_NAME (t1) != NULL
240 && TYPE_NAME (t2) != NULL
241 && !strcmp (TYPE_NAME (t1), TYPE_NAME (t2)))
242 return NULL;
243
244 /* Upcasting: look in the type of the source to see if it contains the
245 type of the target as a superclass. If so, we'll need to
246 offset the pointer rather than just change its type. */
247 if (TYPE_NAME (t1) != NULL)
248 {
249 v = search_struct_field (type_name_no_tag (t1),
250 v2, 0, t2, 1);
251 if (v)
252 return v;
253 }
254
255 /* Downcasting: look in the type of the target to see if it contains the
256 type of the source as a superclass. If so, we'll need to
257 offset the pointer rather than just change its type. */
258 if (TYPE_NAME (t2) != NULL)
259 {
260 /* Try downcasting using the run-time type of the value. */
261 int full, top, using_enc;
262 struct type *real_type;
263
264 real_type = value_rtti_type (v2, &full, &top, &using_enc);
265 if (real_type)
266 {
267 v = value_full_object (v2, real_type, full, top, using_enc);
268 v = value_at_lazy (real_type, value_address (v));
269
270 /* We might be trying to cast to the outermost enclosing
271 type, in which case search_struct_field won't work. */
272 if (TYPE_NAME (real_type) != NULL
273 && !strcmp (TYPE_NAME (real_type), TYPE_NAME (t1)))
274 return v;
275
276 v = search_struct_field (type_name_no_tag (t2), v, 0, real_type, 1);
277 if (v)
278 return v;
279 }
280
281 /* Try downcasting using information from the destination type
282 T2. This wouldn't work properly for classes with virtual
283 bases, but those were handled above. */
284 v = search_struct_field (type_name_no_tag (t2),
285 value_zero (t1, not_lval), 0, t1, 1);
286 if (v)
287 {
288 /* Downcasting is possible (t1 is superclass of v2). */
289 CORE_ADDR addr2 = value_address (v2);
290
291 addr2 -= value_address (v) + value_embedded_offset (v);
292 return value_at (type, addr2);
293 }
294 }
295
296 return NULL;
297 }
298
299 /* Cast one pointer or reference type to another. Both TYPE and
300 the type of ARG2 should be pointer types, or else both should be
301 reference types. Returns the new pointer or reference. */
302
303 struct value *
304 value_cast_pointers (struct type *type, struct value *arg2)
305 {
306 struct type *type1 = check_typedef (type);
307 struct type *type2 = check_typedef (value_type (arg2));
308 struct type *t1 = check_typedef (TYPE_TARGET_TYPE (type1));
309 struct type *t2 = check_typedef (TYPE_TARGET_TYPE (type2));
310
311 if (TYPE_CODE (t1) == TYPE_CODE_STRUCT
312 && TYPE_CODE (t2) == TYPE_CODE_STRUCT
313 && !value_logical_not (arg2))
314 {
315 struct value *v2;
316
317 if (TYPE_CODE (type2) == TYPE_CODE_REF)
318 v2 = coerce_ref (arg2);
319 else
320 v2 = value_ind (arg2);
321 gdb_assert (TYPE_CODE (check_typedef (value_type (v2))) == TYPE_CODE_STRUCT
322 && !!"Why did coercion fail?");
323 v2 = value_cast_structs (t1, v2);
324 /* At this point we have what we can have, un-dereference if needed. */
325 if (v2)
326 {
327 struct value *v = value_addr (v2);
328
329 deprecated_set_value_type (v, type);
330 return v;
331 }
332 }
333
334 /* No superclass found, just change the pointer type. */
335 arg2 = value_copy (arg2);
336 deprecated_set_value_type (arg2, type);
337 arg2 = value_change_enclosing_type (arg2, type);
338 set_value_pointed_to_offset (arg2, 0); /* pai: chk_val */
339 return arg2;
340 }
341
342 /* Cast value ARG2 to type TYPE and return as a value.
343 More general than a C cast: accepts any two types of the same length,
344 and if ARG2 is an lvalue it can be cast into anything at all. */
345 /* In C++, casts may change pointer or object representations. */
346
347 struct value *
348 value_cast (struct type *type, struct value *arg2)
349 {
350 enum type_code code1;
351 enum type_code code2;
352 int scalar;
353 struct type *type2;
354
355 int convert_to_boolean = 0;
356
357 if (value_type (arg2) == type)
358 return arg2;
359
360 code1 = TYPE_CODE (check_typedef (type));
361
362 /* Check if we are casting struct reference to struct reference. */
363 if (code1 == TYPE_CODE_REF)
364 {
365 /* We dereference type; then we recurse and finally
366 we generate value of the given reference. Nothing wrong with
367 that. */
368 struct type *t1 = check_typedef (type);
369 struct type *dereftype = check_typedef (TYPE_TARGET_TYPE (t1));
370 struct value *val = value_cast (dereftype, arg2);
371
372 return value_ref (val);
373 }
374
375 code2 = TYPE_CODE (check_typedef (value_type (arg2)));
376
377 if (code2 == TYPE_CODE_REF)
378 /* We deref the value and then do the cast. */
379 return value_cast (type, coerce_ref (arg2));
380
381 CHECK_TYPEDEF (type);
382 code1 = TYPE_CODE (type);
383 arg2 = coerce_ref (arg2);
384 type2 = check_typedef (value_type (arg2));
385
386 /* You can't cast to a reference type. See value_cast_pointers
387 instead. */
388 gdb_assert (code1 != TYPE_CODE_REF);
389
390 /* A cast to an undetermined-length array_type, such as
391 (TYPE [])OBJECT, is treated like a cast to (TYPE [N])OBJECT,
392 where N is sizeof(OBJECT)/sizeof(TYPE). */
393 if (code1 == TYPE_CODE_ARRAY)
394 {
395 struct type *element_type = TYPE_TARGET_TYPE (type);
396 unsigned element_length = TYPE_LENGTH (check_typedef (element_type));
397
398 if (element_length > 0 && TYPE_ARRAY_UPPER_BOUND_IS_UNDEFINED (type))
399 {
400 struct type *range_type = TYPE_INDEX_TYPE (type);
401 int val_length = TYPE_LENGTH (type2);
402 LONGEST low_bound, high_bound, new_length;
403
404 if (get_discrete_bounds (range_type, &low_bound, &high_bound) < 0)
405 low_bound = 0, high_bound = 0;
406 new_length = val_length / element_length;
407 if (val_length % element_length != 0)
408 warning (_("array element type size does not divide object size in cast"));
409 /* FIXME-type-allocation: need a way to free this type when
410 we are done with it. */
411 range_type = create_range_type ((struct type *) NULL,
412 TYPE_TARGET_TYPE (range_type),
413 low_bound,
414 new_length + low_bound - 1);
415 deprecated_set_value_type (arg2,
416 create_array_type ((struct type *) NULL,
417 element_type,
418 range_type));
419 return arg2;
420 }
421 }
422
423 if (current_language->c_style_arrays
424 && TYPE_CODE (type2) == TYPE_CODE_ARRAY
425 && !TYPE_VECTOR (type2))
426 arg2 = value_coerce_array (arg2);
427
428 if (TYPE_CODE (type2) == TYPE_CODE_FUNC)
429 arg2 = value_coerce_function (arg2);
430
431 type2 = check_typedef (value_type (arg2));
432 code2 = TYPE_CODE (type2);
433
434 if (code1 == TYPE_CODE_COMPLEX)
435 return cast_into_complex (type, arg2);
436 if (code1 == TYPE_CODE_BOOL)
437 {
438 code1 = TYPE_CODE_INT;
439 convert_to_boolean = 1;
440 }
441 if (code1 == TYPE_CODE_CHAR)
442 code1 = TYPE_CODE_INT;
443 if (code2 == TYPE_CODE_BOOL || code2 == TYPE_CODE_CHAR)
444 code2 = TYPE_CODE_INT;
445
446 scalar = (code2 == TYPE_CODE_INT || code2 == TYPE_CODE_FLT
447 || code2 == TYPE_CODE_DECFLOAT || code2 == TYPE_CODE_ENUM
448 || code2 == TYPE_CODE_RANGE);
449
450 if ((code1 == TYPE_CODE_STRUCT || code1 == TYPE_CODE_UNION)
451 && (code2 == TYPE_CODE_STRUCT || code2 == TYPE_CODE_UNION)
452 && TYPE_NAME (type) != 0)
453 {
454 struct value *v = value_cast_structs (type, arg2);
455
456 if (v)
457 return v;
458 }
459
460 if (code1 == TYPE_CODE_FLT && scalar)
461 return value_from_double (type, value_as_double (arg2));
462 else if (code1 == TYPE_CODE_DECFLOAT && scalar)
463 {
464 enum bfd_endian byte_order = gdbarch_byte_order (get_type_arch (type));
465 int dec_len = TYPE_LENGTH (type);
466 gdb_byte dec[16];
467
468 if (code2 == TYPE_CODE_FLT)
469 decimal_from_floating (arg2, dec, dec_len, byte_order);
470 else if (code2 == TYPE_CODE_DECFLOAT)
471 decimal_convert (value_contents (arg2), TYPE_LENGTH (type2),
472 byte_order, dec, dec_len, byte_order);
473 else
474 /* The only option left is an integral type. */
475 decimal_from_integral (arg2, dec, dec_len, byte_order);
476
477 return value_from_decfloat (type, dec);
478 }
479 else if ((code1 == TYPE_CODE_INT || code1 == TYPE_CODE_ENUM
480 || code1 == TYPE_CODE_RANGE)
481 && (scalar || code2 == TYPE_CODE_PTR
482 || code2 == TYPE_CODE_MEMBERPTR))
483 {
484 LONGEST longest;
485
486 /* When we cast pointers to integers, we mustn't use
487 gdbarch_pointer_to_address to find the address the pointer
488 represents, as value_as_long would. GDB should evaluate
489 expressions just as the compiler would --- and the compiler
490 sees a cast as a simple reinterpretation of the pointer's
491 bits. */
492 if (code2 == TYPE_CODE_PTR)
493 longest = extract_unsigned_integer
494 (value_contents (arg2), TYPE_LENGTH (type2),
495 gdbarch_byte_order (get_type_arch (type2)));
496 else
497 longest = value_as_long (arg2);
498 return value_from_longest (type, convert_to_boolean ?
499 (LONGEST) (longest ? 1 : 0) : longest);
500 }
501 else if (code1 == TYPE_CODE_PTR && (code2 == TYPE_CODE_INT
502 || code2 == TYPE_CODE_ENUM
503 || code2 == TYPE_CODE_RANGE))
504 {
505 /* TYPE_LENGTH (type) is the length of a pointer, but we really
506 want the length of an address! -- we are really dealing with
507 addresses (i.e., gdb representations) not pointers (i.e.,
508 target representations) here.
509
510 This allows things like "print *(int *)0x01000234" to work
511 without printing a misleading message -- which would
512 otherwise occur when dealing with a target having two byte
513 pointers and four byte addresses. */
514
515 int addr_bit = gdbarch_addr_bit (get_type_arch (type2));
516 LONGEST longest = value_as_long (arg2);
517
518 if (addr_bit < sizeof (LONGEST) * HOST_CHAR_BIT)
519 {
520 if (longest >= ((LONGEST) 1 << addr_bit)
521 || longest <= -((LONGEST) 1 << addr_bit))
522 warning (_("value truncated"));
523 }
524 return value_from_longest (type, longest);
525 }
526 else if (code1 == TYPE_CODE_METHODPTR && code2 == TYPE_CODE_INT
527 && value_as_long (arg2) == 0)
528 {
529 struct value *result = allocate_value (type);
530
531 cplus_make_method_ptr (type, value_contents_writeable (result), 0, 0);
532 return result;
533 }
534 else if (code1 == TYPE_CODE_MEMBERPTR && code2 == TYPE_CODE_INT
535 && value_as_long (arg2) == 0)
536 {
537 /* The Itanium C++ ABI represents NULL pointers to members as
538 minus one, instead of biasing the normal case. */
539 return value_from_longest (type, -1);
540 }
541 else if (code1 == TYPE_CODE_ARRAY && TYPE_VECTOR (type) && scalar)
542 {
543 /* Widen the scalar to a vector. */
544 struct type *eltype;
545 struct value *val;
546 int i, n;
547
548 eltype = check_typedef (TYPE_TARGET_TYPE (type));
549 arg2 = value_cast (eltype, arg2);
550 val = allocate_value (type);
551 n = TYPE_LENGTH (type) / TYPE_LENGTH (eltype);
552
553 for (i = 0; i < n; i++)
554 {
555 /* Duplicate the contents of arg2 into the destination vector. */
556 memcpy (value_contents_writeable (val) + (i * TYPE_LENGTH (eltype)),
557 value_contents_all (arg2), TYPE_LENGTH (eltype));
558 }
559 return val;
560 }
561 else if (TYPE_LENGTH (type) == TYPE_LENGTH (type2))
562 {
563 if (code1 == TYPE_CODE_PTR && code2 == TYPE_CODE_PTR)
564 return value_cast_pointers (type, arg2);
565
566 arg2 = value_copy (arg2);
567 deprecated_set_value_type (arg2, type);
568 arg2 = value_change_enclosing_type (arg2, type);
569 set_value_pointed_to_offset (arg2, 0); /* pai: chk_val */
570 return arg2;
571 }
572 else if (VALUE_LVAL (arg2) == lval_memory)
573 return value_at_lazy (type, value_address (arg2));
574 else if (code1 == TYPE_CODE_VOID)
575 {
576 return value_zero (type, not_lval);
577 }
578 else
579 {
580 error (_("Invalid cast."));
581 return 0;
582 }
583 }
584
585 /* The C++ reinterpret_cast operator. */
586
587 struct value *
588 value_reinterpret_cast (struct type *type, struct value *arg)
589 {
590 struct value *result;
591 struct type *real_type = check_typedef (type);
592 struct type *arg_type, *dest_type;
593 int is_ref = 0;
594 enum type_code dest_code, arg_code;
595
596 /* Do reference, function, and array conversion. */
597 arg = coerce_array (arg);
598
599 /* Attempt to preserve the type the user asked for. */
600 dest_type = type;
601
602 /* If we are casting to a reference type, transform
603 reinterpret_cast<T&>(V) to *reinterpret_cast<T*>(&V). */
604 if (TYPE_CODE (real_type) == TYPE_CODE_REF)
605 {
606 is_ref = 1;
607 arg = value_addr (arg);
608 dest_type = lookup_pointer_type (TYPE_TARGET_TYPE (dest_type));
609 real_type = lookup_pointer_type (real_type);
610 }
611
612 arg_type = value_type (arg);
613
614 dest_code = TYPE_CODE (real_type);
615 arg_code = TYPE_CODE (arg_type);
616
617 /* We can convert pointer types, or any pointer type to int, or int
618 type to pointer. */
619 if ((dest_code == TYPE_CODE_PTR && arg_code == TYPE_CODE_INT)
620 || (dest_code == TYPE_CODE_INT && arg_code == TYPE_CODE_PTR)
621 || (dest_code == TYPE_CODE_METHODPTR && arg_code == TYPE_CODE_INT)
622 || (dest_code == TYPE_CODE_INT && arg_code == TYPE_CODE_METHODPTR)
623 || (dest_code == TYPE_CODE_MEMBERPTR && arg_code == TYPE_CODE_INT)
624 || (dest_code == TYPE_CODE_INT && arg_code == TYPE_CODE_MEMBERPTR)
625 || (dest_code == arg_code
626 && (dest_code == TYPE_CODE_PTR
627 || dest_code == TYPE_CODE_METHODPTR
628 || dest_code == TYPE_CODE_MEMBERPTR)))
629 result = value_cast (dest_type, arg);
630 else
631 error (_("Invalid reinterpret_cast"));
632
633 if (is_ref)
634 result = value_cast (type, value_ref (value_ind (result)));
635
636 return result;
637 }
638
639 /* A helper for value_dynamic_cast. This implements the first of two
640 runtime checks: we iterate over all the base classes of the value's
641 class which are equal to the desired class; if only one of these
642 holds the value, then it is the answer. */
643
644 static int
645 dynamic_cast_check_1 (struct type *desired_type,
646 const bfd_byte *contents,
647 CORE_ADDR address,
648 struct type *search_type,
649 CORE_ADDR arg_addr,
650 struct type *arg_type,
651 struct value **result)
652 {
653 int i, result_count = 0;
654
655 for (i = 0; i < TYPE_N_BASECLASSES (search_type) && result_count < 2; ++i)
656 {
657 int offset = baseclass_offset (search_type, i, contents, address);
658
659 if (offset == -1)
660 error (_("virtual baseclass botch"));
661 if (class_types_same_p (desired_type, TYPE_BASECLASS (search_type, i)))
662 {
663 if (address + offset >= arg_addr
664 && address + offset < arg_addr + TYPE_LENGTH (arg_type))
665 {
666 ++result_count;
667 if (!*result)
668 *result = value_at_lazy (TYPE_BASECLASS (search_type, i),
669 address + offset);
670 }
671 }
672 else
673 result_count += dynamic_cast_check_1 (desired_type,
674 contents + offset,
675 address + offset,
676 TYPE_BASECLASS (search_type, i),
677 arg_addr,
678 arg_type,
679 result);
680 }
681
682 return result_count;
683 }
684
685 /* A helper for value_dynamic_cast. This implements the second of two
686 runtime checks: we look for a unique public sibling class of the
687 argument's declared class. */
688
689 static int
690 dynamic_cast_check_2 (struct type *desired_type,
691 const bfd_byte *contents,
692 CORE_ADDR address,
693 struct type *search_type,
694 struct value **result)
695 {
696 int i, result_count = 0;
697
698 for (i = 0; i < TYPE_N_BASECLASSES (search_type) && result_count < 2; ++i)
699 {
700 int offset;
701
702 if (! BASETYPE_VIA_PUBLIC (search_type, i))
703 continue;
704
705 offset = baseclass_offset (search_type, i, contents, address);
706 if (offset == -1)
707 error (_("virtual baseclass botch"));
708 if (class_types_same_p (desired_type, TYPE_BASECLASS (search_type, i)))
709 {
710 ++result_count;
711 if (*result == NULL)
712 *result = value_at_lazy (TYPE_BASECLASS (search_type, i),
713 address + offset);
714 }
715 else
716 result_count += dynamic_cast_check_2 (desired_type,
717 contents + offset,
718 address + offset,
719 TYPE_BASECLASS (search_type, i),
720 result);
721 }
722
723 return result_count;
724 }
725
726 /* The C++ dynamic_cast operator. */
727
728 struct value *
729 value_dynamic_cast (struct type *type, struct value *arg)
730 {
731 int full, top, using_enc;
732 struct type *resolved_type = check_typedef (type);
733 struct type *arg_type = check_typedef (value_type (arg));
734 struct type *class_type, *rtti_type;
735 struct value *result, *tem, *original_arg = arg;
736 CORE_ADDR addr;
737 int is_ref = TYPE_CODE (resolved_type) == TYPE_CODE_REF;
738
739 if (TYPE_CODE (resolved_type) != TYPE_CODE_PTR
740 && TYPE_CODE (resolved_type) != TYPE_CODE_REF)
741 error (_("Argument to dynamic_cast must be a pointer or reference type"));
742 if (TYPE_CODE (TYPE_TARGET_TYPE (resolved_type)) != TYPE_CODE_VOID
743 && TYPE_CODE (TYPE_TARGET_TYPE (resolved_type)) != TYPE_CODE_CLASS)
744 error (_("Argument to dynamic_cast must be pointer to class or `void *'"));
745
746 class_type = check_typedef (TYPE_TARGET_TYPE (resolved_type));
747 if (TYPE_CODE (resolved_type) == TYPE_CODE_PTR)
748 {
749 if (TYPE_CODE (arg_type) != TYPE_CODE_PTR
750 && ! (TYPE_CODE (arg_type) == TYPE_CODE_INT
751 && value_as_long (arg) == 0))
752 error (_("Argument to dynamic_cast does not have pointer type"));
753 if (TYPE_CODE (arg_type) == TYPE_CODE_PTR)
754 {
755 arg_type = check_typedef (TYPE_TARGET_TYPE (arg_type));
756 if (TYPE_CODE (arg_type) != TYPE_CODE_CLASS)
757 error (_("Argument to dynamic_cast does not have pointer to class type"));
758 }
759
760 /* Handle NULL pointers. */
761 if (value_as_long (arg) == 0)
762 return value_zero (type, not_lval);
763
764 arg = value_ind (arg);
765 }
766 else
767 {
768 if (TYPE_CODE (arg_type) != TYPE_CODE_CLASS)
769 error (_("Argument to dynamic_cast does not have class type"));
770 }
771
772 /* If the classes are the same, just return the argument. */
773 if (class_types_same_p (class_type, arg_type))
774 return value_cast (type, arg);
775
776 /* If the target type is a unique base class of the argument's
777 declared type, just cast it. */
778 if (is_ancestor (class_type, arg_type))
779 {
780 if (is_unique_ancestor (class_type, arg))
781 return value_cast (type, original_arg);
782 error (_("Ambiguous dynamic_cast"));
783 }
784
785 rtti_type = value_rtti_type (arg, &full, &top, &using_enc);
786 if (! rtti_type)
787 error (_("Couldn't determine value's most derived type for dynamic_cast"));
788
789 /* Compute the most derived object's address. */
790 addr = value_address (arg);
791 if (full)
792 {
793 /* Done. */
794 }
795 else if (using_enc)
796 addr += top;
797 else
798 addr += top + value_embedded_offset (arg);
799
800 /* dynamic_cast<void *> means to return a pointer to the
801 most-derived object. */
802 if (TYPE_CODE (resolved_type) == TYPE_CODE_PTR
803 && TYPE_CODE (TYPE_TARGET_TYPE (resolved_type)) == TYPE_CODE_VOID)
804 return value_at_lazy (type, addr);
805
806 tem = value_at (type, addr);
807
808 /* The first dynamic check specified in 5.2.7. */
809 if (is_public_ancestor (arg_type, TYPE_TARGET_TYPE (resolved_type)))
810 {
811 if (class_types_same_p (rtti_type, TYPE_TARGET_TYPE (resolved_type)))
812 return tem;
813 result = NULL;
814 if (dynamic_cast_check_1 (TYPE_TARGET_TYPE (resolved_type),
815 value_contents (tem), value_address (tem),
816 rtti_type, addr,
817 arg_type,
818 &result) == 1)
819 return value_cast (type,
820 is_ref ? value_ref (result) : value_addr (result));
821 }
822
823 /* The second dynamic check specified in 5.2.7. */
824 result = NULL;
825 if (is_public_ancestor (arg_type, rtti_type)
826 && dynamic_cast_check_2 (TYPE_TARGET_TYPE (resolved_type),
827 value_contents (tem), value_address (tem),
828 rtti_type, &result) == 1)
829 return value_cast (type,
830 is_ref ? value_ref (result) : value_addr (result));
831
832 if (TYPE_CODE (resolved_type) == TYPE_CODE_PTR)
833 return value_zero (type, not_lval);
834
835 error (_("dynamic_cast failed"));
836 }
837
838 /* Create a value of type TYPE that is zero, and return it. */
839
840 struct value *
841 value_zero (struct type *type, enum lval_type lv)
842 {
843 struct value *val = allocate_value (type);
844
845 VALUE_LVAL (val) = lv;
846 return val;
847 }
848
849 /* Create a value of numeric type TYPE that is one, and return it. */
850
851 struct value *
852 value_one (struct type *type, enum lval_type lv)
853 {
854 struct type *type1 = check_typedef (type);
855 struct value *val;
856
857 if (TYPE_CODE (type1) == TYPE_CODE_DECFLOAT)
858 {
859 enum bfd_endian byte_order = gdbarch_byte_order (get_type_arch (type));
860 gdb_byte v[16];
861
862 decimal_from_string (v, TYPE_LENGTH (type), byte_order, "1");
863 val = value_from_decfloat (type, v);
864 }
865 else if (TYPE_CODE (type1) == TYPE_CODE_FLT)
866 {
867 val = value_from_double (type, (DOUBLEST) 1);
868 }
869 else if (is_integral_type (type1))
870 {
871 val = value_from_longest (type, (LONGEST) 1);
872 }
873 else
874 {
875 error (_("Not a numeric type."));
876 }
877
878 VALUE_LVAL (val) = lv;
879 return val;
880 }
881
882 /* Helper function for value_at, value_at_lazy, and value_at_lazy_stack. */
883
884 static struct value *
885 get_value_at (struct type *type, CORE_ADDR addr, int lazy)
886 {
887 struct value *val;
888
889 if (TYPE_CODE (check_typedef (type)) == TYPE_CODE_VOID)
890 error (_("Attempt to dereference a generic pointer."));
891
892 if (lazy)
893 {
894 val = allocate_value_lazy (type);
895 }
896 else
897 {
898 val = allocate_value (type);
899 read_memory (addr, value_contents_all_raw (val), TYPE_LENGTH (type));
900 }
901
902 VALUE_LVAL (val) = lval_memory;
903 set_value_address (val, addr);
904
905 return val;
906 }
907
908 /* Return a value with type TYPE located at ADDR.
909
910 Call value_at only if the data needs to be fetched immediately;
911 if we can be 'lazy' and defer the fetch, perhaps indefinately, call
912 value_at_lazy instead. value_at_lazy simply records the address of
913 the data and sets the lazy-evaluation-required flag. The lazy flag
914 is tested in the value_contents macro, which is used if and when
915 the contents are actually required.
916
917 Note: value_at does *NOT* handle embedded offsets; perform such
918 adjustments before or after calling it. */
919
920 struct value *
921 value_at (struct type *type, CORE_ADDR addr)
922 {
923 return get_value_at (type, addr, 0);
924 }
925
926 /* Return a lazy value with type TYPE located at ADDR (cf. value_at). */
927
928 struct value *
929 value_at_lazy (struct type *type, CORE_ADDR addr)
930 {
931 return get_value_at (type, addr, 1);
932 }
933
934 /* Called only from the value_contents and value_contents_all()
935 macros, if the current data for a variable needs to be loaded into
936 value_contents(VAL). Fetches the data from the user's process, and
937 clears the lazy flag to indicate that the data in the buffer is
938 valid.
939
940 If the value is zero-length, we avoid calling read_memory, which
941 would abort. We mark the value as fetched anyway -- all 0 bytes of
942 it.
943
944 This function returns a value because it is used in the
945 value_contents macro as part of an expression, where a void would
946 not work. The value is ignored. */
947
948 int
949 value_fetch_lazy (struct value *val)
950 {
951 gdb_assert (value_lazy (val));
952 allocate_value_contents (val);
953 if (value_bitsize (val))
954 {
955 /* To read a lazy bitfield, read the entire enclosing value. This
956 prevents reading the same block of (possibly volatile) memory once
957 per bitfield. It would be even better to read only the containing
958 word, but we have no way to record that just specific bits of a
959 value have been fetched. */
960 struct type *type = check_typedef (value_type (val));
961 enum bfd_endian byte_order = gdbarch_byte_order (get_type_arch (type));
962 struct value *parent = value_parent (val);
963 LONGEST offset = value_offset (val);
964 LONGEST num = unpack_bits_as_long (value_type (val),
965 (value_contents_for_printing (parent)
966 + offset),
967 value_bitpos (val),
968 value_bitsize (val));
969 int length = TYPE_LENGTH (type);
970
971 if (!value_bits_valid (val,
972 TARGET_CHAR_BIT * offset + value_bitpos (val),
973 value_bitsize (val)))
974 error (_("value has been optimized out"));
975
976 store_signed_integer (value_contents_raw (val), length, byte_order, num);
977 }
978 else if (VALUE_LVAL (val) == lval_memory)
979 {
980 CORE_ADDR addr = value_address (val);
981 int length = TYPE_LENGTH (check_typedef (value_enclosing_type (val)));
982
983 if (length)
984 {
985 if (value_stack (val))
986 read_stack (addr, value_contents_all_raw (val), length);
987 else
988 read_memory (addr, value_contents_all_raw (val), length);
989 }
990 }
991 else if (VALUE_LVAL (val) == lval_register)
992 {
993 struct frame_info *frame;
994 int regnum;
995 struct type *type = check_typedef (value_type (val));
996 struct value *new_val = val, *mark = value_mark ();
997
998 /* Offsets are not supported here; lazy register values must
999 refer to the entire register. */
1000 gdb_assert (value_offset (val) == 0);
1001
1002 while (VALUE_LVAL (new_val) == lval_register && value_lazy (new_val))
1003 {
1004 frame = frame_find_by_id (VALUE_FRAME_ID (new_val));
1005 regnum = VALUE_REGNUM (new_val);
1006
1007 gdb_assert (frame != NULL);
1008
1009 /* Convertible register routines are used for multi-register
1010 values and for interpretation in different types
1011 (e.g. float or int from a double register). Lazy
1012 register values should have the register's natural type,
1013 so they do not apply. */
1014 gdb_assert (!gdbarch_convert_register_p (get_frame_arch (frame),
1015 regnum, type));
1016
1017 new_val = get_frame_register_value (frame, regnum);
1018 }
1019
1020 /* If it's still lazy (for instance, a saved register on the
1021 stack), fetch it. */
1022 if (value_lazy (new_val))
1023 value_fetch_lazy (new_val);
1024
1025 /* If the register was not saved, mark it unavailable. */
1026 if (value_optimized_out (new_val))
1027 set_value_optimized_out (val, 1);
1028 else
1029 memcpy (value_contents_raw (val), value_contents (new_val),
1030 TYPE_LENGTH (type));
1031
1032 if (frame_debug)
1033 {
1034 struct gdbarch *gdbarch;
1035 frame = frame_find_by_id (VALUE_FRAME_ID (val));
1036 regnum = VALUE_REGNUM (val);
1037 gdbarch = get_frame_arch (frame);
1038
1039 fprintf_unfiltered (gdb_stdlog, "\
1040 { value_fetch_lazy (frame=%d,regnum=%d(%s),...) ",
1041 frame_relative_level (frame), regnum,
1042 user_reg_map_regnum_to_name (gdbarch, regnum));
1043
1044 fprintf_unfiltered (gdb_stdlog, "->");
1045 if (value_optimized_out (new_val))
1046 fprintf_unfiltered (gdb_stdlog, " optimized out");
1047 else
1048 {
1049 int i;
1050 const gdb_byte *buf = value_contents (new_val);
1051
1052 if (VALUE_LVAL (new_val) == lval_register)
1053 fprintf_unfiltered (gdb_stdlog, " register=%d",
1054 VALUE_REGNUM (new_val));
1055 else if (VALUE_LVAL (new_val) == lval_memory)
1056 fprintf_unfiltered (gdb_stdlog, " address=%s",
1057 paddress (gdbarch,
1058 value_address (new_val)));
1059 else
1060 fprintf_unfiltered (gdb_stdlog, " computed");
1061
1062 fprintf_unfiltered (gdb_stdlog, " bytes=");
1063 fprintf_unfiltered (gdb_stdlog, "[");
1064 for (i = 0; i < register_size (gdbarch, regnum); i++)
1065 fprintf_unfiltered (gdb_stdlog, "%02x", buf[i]);
1066 fprintf_unfiltered (gdb_stdlog, "]");
1067 }
1068
1069 fprintf_unfiltered (gdb_stdlog, " }\n");
1070 }
1071
1072 /* Dispose of the intermediate values. This prevents
1073 watchpoints from trying to watch the saved frame pointer. */
1074 value_free_to_mark (mark);
1075 }
1076 else if (VALUE_LVAL (val) == lval_computed)
1077 value_computed_funcs (val)->read (val);
1078 else
1079 internal_error (__FILE__, __LINE__, "Unexpected lazy value type.");
1080
1081 set_value_lazy (val, 0);
1082 return 0;
1083 }
1084
1085
1086 /* Store the contents of FROMVAL into the location of TOVAL.
1087 Return a new value with the location of TOVAL and contents of FROMVAL. */
1088
1089 struct value *
1090 value_assign (struct value *toval, struct value *fromval)
1091 {
1092 struct type *type;
1093 struct value *val;
1094 struct frame_id old_frame;
1095
1096 if (!deprecated_value_modifiable (toval))
1097 error (_("Left operand of assignment is not a modifiable lvalue."));
1098
1099 toval = coerce_ref (toval);
1100
1101 type = value_type (toval);
1102 if (VALUE_LVAL (toval) != lval_internalvar)
1103 fromval = value_cast (type, fromval);
1104 else
1105 {
1106 /* Coerce arrays and functions to pointers, except for arrays
1107 which only live in GDB's storage. */
1108 if (!value_must_coerce_to_target (fromval))
1109 fromval = coerce_array (fromval);
1110 }
1111
1112 CHECK_TYPEDEF (type);
1113
1114 /* Since modifying a register can trash the frame chain, and
1115 modifying memory can trash the frame cache, we save the old frame
1116 and then restore the new frame afterwards. */
1117 old_frame = get_frame_id (deprecated_safe_get_selected_frame ());
1118
1119 switch (VALUE_LVAL (toval))
1120 {
1121 case lval_internalvar:
1122 set_internalvar (VALUE_INTERNALVAR (toval), fromval);
1123 val = value_copy (fromval);
1124 val = value_change_enclosing_type (val,
1125 value_enclosing_type (fromval));
1126 set_value_embedded_offset (val, value_embedded_offset (fromval));
1127 set_value_pointed_to_offset (val,
1128 value_pointed_to_offset (fromval));
1129 return val;
1130
1131 case lval_internalvar_component:
1132 set_internalvar_component (VALUE_INTERNALVAR (toval),
1133 value_offset (toval),
1134 value_bitpos (toval),
1135 value_bitsize (toval),
1136 fromval);
1137 break;
1138
1139 case lval_memory:
1140 {
1141 const gdb_byte *dest_buffer;
1142 CORE_ADDR changed_addr;
1143 int changed_len;
1144 gdb_byte buffer[sizeof (LONGEST)];
1145
1146 if (value_bitsize (toval))
1147 {
1148 struct value *parent = value_parent (toval);
1149
1150 changed_addr = value_address (parent) + value_offset (toval);
1151 changed_len = (value_bitpos (toval)
1152 + value_bitsize (toval)
1153 + HOST_CHAR_BIT - 1)
1154 / HOST_CHAR_BIT;
1155
1156 /* If we can read-modify-write exactly the size of the
1157 containing type (e.g. short or int) then do so. This
1158 is safer for volatile bitfields mapped to hardware
1159 registers. */
1160 if (changed_len < TYPE_LENGTH (type)
1161 && TYPE_LENGTH (type) <= (int) sizeof (LONGEST)
1162 && ((LONGEST) changed_addr % TYPE_LENGTH (type)) == 0)
1163 changed_len = TYPE_LENGTH (type);
1164
1165 if (changed_len > (int) sizeof (LONGEST))
1166 error (_("Can't handle bitfields which don't fit in a %d bit word."),
1167 (int) sizeof (LONGEST) * HOST_CHAR_BIT);
1168
1169 read_memory (changed_addr, buffer, changed_len);
1170 modify_field (type, buffer, value_as_long (fromval),
1171 value_bitpos (toval), value_bitsize (toval));
1172 dest_buffer = buffer;
1173 }
1174 else
1175 {
1176 changed_addr = value_address (toval);
1177 changed_len = TYPE_LENGTH (type);
1178 dest_buffer = value_contents (fromval);
1179 }
1180
1181 write_memory (changed_addr, dest_buffer, changed_len);
1182 observer_notify_memory_changed (changed_addr, changed_len,
1183 dest_buffer);
1184 }
1185 break;
1186
1187 case lval_register:
1188 {
1189 struct frame_info *frame;
1190 struct gdbarch *gdbarch;
1191 int value_reg;
1192
1193 /* Figure out which frame this is in currently. */
1194 frame = frame_find_by_id (VALUE_FRAME_ID (toval));
1195 value_reg = VALUE_REGNUM (toval);
1196
1197 if (!frame)
1198 error (_("Value being assigned to is no longer active."));
1199
1200 gdbarch = get_frame_arch (frame);
1201 if (gdbarch_convert_register_p (gdbarch, VALUE_REGNUM (toval), type))
1202 {
1203 /* If TOVAL is a special machine register requiring
1204 conversion of program values to a special raw
1205 format. */
1206 gdbarch_value_to_register (gdbarch, frame,
1207 VALUE_REGNUM (toval), type,
1208 value_contents (fromval));
1209 }
1210 else
1211 {
1212 if (value_bitsize (toval))
1213 {
1214 struct value *parent = value_parent (toval);
1215 int offset = value_offset (parent) + value_offset (toval);
1216 int changed_len;
1217 gdb_byte buffer[sizeof (LONGEST)];
1218
1219 changed_len = (value_bitpos (toval)
1220 + value_bitsize (toval)
1221 + HOST_CHAR_BIT - 1)
1222 / HOST_CHAR_BIT;
1223
1224 if (changed_len > (int) sizeof (LONGEST))
1225 error (_("Can't handle bitfields which don't fit in a %d bit word."),
1226 (int) sizeof (LONGEST) * HOST_CHAR_BIT);
1227
1228 get_frame_register_bytes (frame, value_reg, offset,
1229 changed_len, buffer);
1230
1231 modify_field (type, buffer, value_as_long (fromval),
1232 value_bitpos (toval), value_bitsize (toval));
1233
1234 put_frame_register_bytes (frame, value_reg, offset,
1235 changed_len, buffer);
1236 }
1237 else
1238 {
1239 put_frame_register_bytes (frame, value_reg,
1240 value_offset (toval),
1241 TYPE_LENGTH (type),
1242 value_contents (fromval));
1243 }
1244 }
1245
1246 if (deprecated_register_changed_hook)
1247 deprecated_register_changed_hook (-1);
1248 observer_notify_target_changed (&current_target);
1249 break;
1250 }
1251
1252 case lval_computed:
1253 {
1254 struct lval_funcs *funcs = value_computed_funcs (toval);
1255
1256 funcs->write (toval, fromval);
1257 }
1258 break;
1259
1260 default:
1261 error (_("Left operand of assignment is not an lvalue."));
1262 }
1263
1264 /* Assigning to the stack pointer, frame pointer, and other
1265 (architecture and calling convention specific) registers may
1266 cause the frame cache to be out of date. Assigning to memory
1267 also can. We just do this on all assignments to registers or
1268 memory, for simplicity's sake; I doubt the slowdown matters. */
1269 switch (VALUE_LVAL (toval))
1270 {
1271 case lval_memory:
1272 case lval_register:
1273 case lval_computed:
1274
1275 reinit_frame_cache ();
1276
1277 /* Having destroyed the frame cache, restore the selected
1278 frame. */
1279
1280 /* FIXME: cagney/2002-11-02: There has to be a better way of
1281 doing this. Instead of constantly saving/restoring the
1282 frame. Why not create a get_selected_frame() function that,
1283 having saved the selected frame's ID can automatically
1284 re-find the previously selected frame automatically. */
1285
1286 {
1287 struct frame_info *fi = frame_find_by_id (old_frame);
1288
1289 if (fi != NULL)
1290 select_frame (fi);
1291 }
1292
1293 break;
1294 default:
1295 break;
1296 }
1297
1298 /* If the field does not entirely fill a LONGEST, then zero the sign
1299 bits. If the field is signed, and is negative, then sign
1300 extend. */
1301 if ((value_bitsize (toval) > 0)
1302 && (value_bitsize (toval) < 8 * (int) sizeof (LONGEST)))
1303 {
1304 LONGEST fieldval = value_as_long (fromval);
1305 LONGEST valmask = (((ULONGEST) 1) << value_bitsize (toval)) - 1;
1306
1307 fieldval &= valmask;
1308 if (!TYPE_UNSIGNED (type)
1309 && (fieldval & (valmask ^ (valmask >> 1))))
1310 fieldval |= ~valmask;
1311
1312 fromval = value_from_longest (type, fieldval);
1313 }
1314
1315 val = value_copy (toval);
1316 memcpy (value_contents_raw (val), value_contents (fromval),
1317 TYPE_LENGTH (type));
1318 deprecated_set_value_type (val, type);
1319 val = value_change_enclosing_type (val,
1320 value_enclosing_type (fromval));
1321 set_value_embedded_offset (val, value_embedded_offset (fromval));
1322 set_value_pointed_to_offset (val, value_pointed_to_offset (fromval));
1323
1324 return val;
1325 }
1326
1327 /* Extend a value VAL to COUNT repetitions of its type. */
1328
1329 struct value *
1330 value_repeat (struct value *arg1, int count)
1331 {
1332 struct value *val;
1333
1334 if (VALUE_LVAL (arg1) != lval_memory)
1335 error (_("Only values in memory can be extended with '@'."));
1336 if (count < 1)
1337 error (_("Invalid number %d of repetitions."), count);
1338
1339 val = allocate_repeat_value (value_enclosing_type (arg1), count);
1340
1341 read_memory (value_address (arg1),
1342 value_contents_all_raw (val),
1343 TYPE_LENGTH (value_enclosing_type (val)));
1344 VALUE_LVAL (val) = lval_memory;
1345 set_value_address (val, value_address (arg1));
1346
1347 return val;
1348 }
1349
1350 struct value *
1351 value_of_variable (struct symbol *var, struct block *b)
1352 {
1353 struct value *val;
1354 struct frame_info *frame;
1355
1356 if (!symbol_read_needs_frame (var))
1357 frame = NULL;
1358 else if (!b)
1359 frame = get_selected_frame (_("No frame selected."));
1360 else
1361 {
1362 frame = block_innermost_frame (b);
1363 if (!frame)
1364 {
1365 if (BLOCK_FUNCTION (b) && !block_inlined_p (b)
1366 && SYMBOL_PRINT_NAME (BLOCK_FUNCTION (b)))
1367 error (_("No frame is currently executing in block %s."),
1368 SYMBOL_PRINT_NAME (BLOCK_FUNCTION (b)));
1369 else
1370 error (_("No frame is currently executing in specified block"));
1371 }
1372 }
1373
1374 val = read_var_value (var, frame);
1375 if (!val)
1376 error (_("Address of symbol \"%s\" is unknown."), SYMBOL_PRINT_NAME (var));
1377
1378 return val;
1379 }
1380
1381 struct value *
1382 address_of_variable (struct symbol *var, struct block *b)
1383 {
1384 struct type *type = SYMBOL_TYPE (var);
1385 struct value *val;
1386
1387 /* Evaluate it first; if the result is a memory address, we're fine.
1388 Lazy evaluation pays off here. */
1389
1390 val = value_of_variable (var, b);
1391
1392 if ((VALUE_LVAL (val) == lval_memory && value_lazy (val))
1393 || TYPE_CODE (type) == TYPE_CODE_FUNC)
1394 {
1395 CORE_ADDR addr = value_address (val);
1396
1397 return value_from_pointer (lookup_pointer_type (type), addr);
1398 }
1399
1400 /* Not a memory address; check what the problem was. */
1401 switch (VALUE_LVAL (val))
1402 {
1403 case lval_register:
1404 {
1405 struct frame_info *frame;
1406 const char *regname;
1407
1408 frame = frame_find_by_id (VALUE_FRAME_ID (val));
1409 gdb_assert (frame);
1410
1411 regname = gdbarch_register_name (get_frame_arch (frame),
1412 VALUE_REGNUM (val));
1413 gdb_assert (regname && *regname);
1414
1415 error (_("Address requested for identifier "
1416 "\"%s\" which is in register $%s"),
1417 SYMBOL_PRINT_NAME (var), regname);
1418 break;
1419 }
1420
1421 default:
1422 error (_("Can't take address of \"%s\" which isn't an lvalue."),
1423 SYMBOL_PRINT_NAME (var));
1424 break;
1425 }
1426
1427 return val;
1428 }
1429
1430 /* Return one if VAL does not live in target memory, but should in order
1431 to operate on it. Otherwise return zero. */
1432
1433 int
1434 value_must_coerce_to_target (struct value *val)
1435 {
1436 struct type *valtype;
1437
1438 /* The only lval kinds which do not live in target memory. */
1439 if (VALUE_LVAL (val) != not_lval
1440 && VALUE_LVAL (val) != lval_internalvar)
1441 return 0;
1442
1443 valtype = check_typedef (value_type (val));
1444
1445 switch (TYPE_CODE (valtype))
1446 {
1447 case TYPE_CODE_ARRAY:
1448 return TYPE_VECTOR (valtype) ? 0 : 1;
1449 case TYPE_CODE_STRING:
1450 return 1;
1451 default:
1452 return 0;
1453 }
1454 }
1455
1456 /* Make sure that VAL lives in target memory if it's supposed to. For instance,
1457 strings are constructed as character arrays in GDB's storage, and this
1458 function copies them to the target. */
1459
1460 struct value *
1461 value_coerce_to_target (struct value *val)
1462 {
1463 LONGEST length;
1464 CORE_ADDR addr;
1465
1466 if (!value_must_coerce_to_target (val))
1467 return val;
1468
1469 length = TYPE_LENGTH (check_typedef (value_type (val)));
1470 addr = allocate_space_in_inferior (length);
1471 write_memory (addr, value_contents (val), length);
1472 return value_at_lazy (value_type (val), addr);
1473 }
1474
1475 /* Given a value which is an array, return a value which is a pointer
1476 to its first element, regardless of whether or not the array has a
1477 nonzero lower bound.
1478
1479 FIXME: A previous comment here indicated that this routine should
1480 be substracting the array's lower bound. It's not clear to me that
1481 this is correct. Given an array subscripting operation, it would
1482 certainly work to do the adjustment here, essentially computing:
1483
1484 (&array[0] - (lowerbound * sizeof array[0])) + (index * sizeof array[0])
1485
1486 However I believe a more appropriate and logical place to account
1487 for the lower bound is to do so in value_subscript, essentially
1488 computing:
1489
1490 (&array[0] + ((index - lowerbound) * sizeof array[0]))
1491
1492 As further evidence consider what would happen with operations
1493 other than array subscripting, where the caller would get back a
1494 value that had an address somewhere before the actual first element
1495 of the array, and the information about the lower bound would be
1496 lost because of the coercion to pointer type.
1497 */
1498
1499 struct value *
1500 value_coerce_array (struct value *arg1)
1501 {
1502 struct type *type = check_typedef (value_type (arg1));
1503
1504 /* If the user tries to do something requiring a pointer with an
1505 array that has not yet been pushed to the target, then this would
1506 be a good time to do so. */
1507 arg1 = value_coerce_to_target (arg1);
1508
1509 if (VALUE_LVAL (arg1) != lval_memory)
1510 error (_("Attempt to take address of value not located in memory."));
1511
1512 return value_from_pointer (lookup_pointer_type (TYPE_TARGET_TYPE (type)),
1513 value_address (arg1));
1514 }
1515
1516 /* Given a value which is a function, return a value which is a pointer
1517 to it. */
1518
1519 struct value *
1520 value_coerce_function (struct value *arg1)
1521 {
1522 struct value *retval;
1523
1524 if (VALUE_LVAL (arg1) != lval_memory)
1525 error (_("Attempt to take address of value not located in memory."));
1526
1527 retval = value_from_pointer (lookup_pointer_type (value_type (arg1)),
1528 value_address (arg1));
1529 return retval;
1530 }
1531
1532 /* Return a pointer value for the object for which ARG1 is the
1533 contents. */
1534
1535 struct value *
1536 value_addr (struct value *arg1)
1537 {
1538 struct value *arg2;
1539 struct type *type = check_typedef (value_type (arg1));
1540
1541 if (TYPE_CODE (type) == TYPE_CODE_REF)
1542 {
1543 /* Copy the value, but change the type from (T&) to (T*). We
1544 keep the same location information, which is efficient, and
1545 allows &(&X) to get the location containing the reference. */
1546 arg2 = value_copy (arg1);
1547 deprecated_set_value_type (arg2,
1548 lookup_pointer_type (TYPE_TARGET_TYPE (type)));
1549 return arg2;
1550 }
1551 if (TYPE_CODE (type) == TYPE_CODE_FUNC)
1552 return value_coerce_function (arg1);
1553
1554 /* If this is an array that has not yet been pushed to the target,
1555 then this would be a good time to force it to memory. */
1556 arg1 = value_coerce_to_target (arg1);
1557
1558 if (VALUE_LVAL (arg1) != lval_memory)
1559 error (_("Attempt to take address of value not located in memory."));
1560
1561 /* Get target memory address */
1562 arg2 = value_from_pointer (lookup_pointer_type (value_type (arg1)),
1563 (value_address (arg1)
1564 + value_embedded_offset (arg1)));
1565
1566 /* This may be a pointer to a base subobject; so remember the
1567 full derived object's type ... */
1568 arg2 = value_change_enclosing_type (arg2, lookup_pointer_type (value_enclosing_type (arg1)));
1569 /* ... and also the relative position of the subobject in the full
1570 object. */
1571 set_value_pointed_to_offset (arg2, value_embedded_offset (arg1));
1572 return arg2;
1573 }
1574
1575 /* Return a reference value for the object for which ARG1 is the
1576 contents. */
1577
1578 struct value *
1579 value_ref (struct value *arg1)
1580 {
1581 struct value *arg2;
1582 struct type *type = check_typedef (value_type (arg1));
1583
1584 if (TYPE_CODE (type) == TYPE_CODE_REF)
1585 return arg1;
1586
1587 arg2 = value_addr (arg1);
1588 deprecated_set_value_type (arg2, lookup_reference_type (type));
1589 return arg2;
1590 }
1591
1592 /* Given a value of a pointer type, apply the C unary * operator to
1593 it. */
1594
1595 struct value *
1596 value_ind (struct value *arg1)
1597 {
1598 struct type *base_type;
1599 struct value *arg2;
1600
1601 arg1 = coerce_array (arg1);
1602
1603 base_type = check_typedef (value_type (arg1));
1604
1605 if (TYPE_CODE (base_type) == TYPE_CODE_PTR)
1606 {
1607 struct type *enc_type;
1608
1609 /* We may be pointing to something embedded in a larger object.
1610 Get the real type of the enclosing object. */
1611 enc_type = check_typedef (value_enclosing_type (arg1));
1612 enc_type = TYPE_TARGET_TYPE (enc_type);
1613
1614 if (TYPE_CODE (check_typedef (enc_type)) == TYPE_CODE_FUNC
1615 || TYPE_CODE (check_typedef (enc_type)) == TYPE_CODE_METHOD)
1616 /* For functions, go through find_function_addr, which knows
1617 how to handle function descriptors. */
1618 arg2 = value_at_lazy (enc_type,
1619 find_function_addr (arg1, NULL));
1620 else
1621 /* Retrieve the enclosing object pointed to */
1622 arg2 = value_at_lazy (enc_type,
1623 (value_as_address (arg1)
1624 - value_pointed_to_offset (arg1)));
1625
1626 /* Re-adjust type. */
1627 deprecated_set_value_type (arg2, TYPE_TARGET_TYPE (base_type));
1628 /* Add embedding info. */
1629 arg2 = value_change_enclosing_type (arg2, enc_type);
1630 set_value_embedded_offset (arg2, value_pointed_to_offset (arg1));
1631
1632 /* We may be pointing to an object of some derived type. */
1633 arg2 = value_full_object (arg2, NULL, 0, 0, 0);
1634 return arg2;
1635 }
1636
1637 error (_("Attempt to take contents of a non-pointer value."));
1638 return 0; /* For lint -- never reached. */
1639 }
1640 \f
1641 /* Create a value for an array by allocating space in GDB, copying
1642 copying the data into that space, and then setting up an array
1643 value.
1644
1645 The array bounds are set from LOWBOUND and HIGHBOUND, and the array
1646 is populated from the values passed in ELEMVEC.
1647
1648 The element type of the array is inherited from the type of the
1649 first element, and all elements must have the same size (though we
1650 don't currently enforce any restriction on their types). */
1651
1652 struct value *
1653 value_array (int lowbound, int highbound, struct value **elemvec)
1654 {
1655 int nelem;
1656 int idx;
1657 unsigned int typelength;
1658 struct value *val;
1659 struct type *arraytype;
1660
1661 /* Validate that the bounds are reasonable and that each of the
1662 elements have the same size. */
1663
1664 nelem = highbound - lowbound + 1;
1665 if (nelem <= 0)
1666 {
1667 error (_("bad array bounds (%d, %d)"), lowbound, highbound);
1668 }
1669 typelength = TYPE_LENGTH (value_enclosing_type (elemvec[0]));
1670 for (idx = 1; idx < nelem; idx++)
1671 {
1672 if (TYPE_LENGTH (value_enclosing_type (elemvec[idx])) != typelength)
1673 {
1674 error (_("array elements must all be the same size"));
1675 }
1676 }
1677
1678 arraytype = lookup_array_range_type (value_enclosing_type (elemvec[0]),
1679 lowbound, highbound);
1680
1681 if (!current_language->c_style_arrays)
1682 {
1683 val = allocate_value (arraytype);
1684 for (idx = 0; idx < nelem; idx++)
1685 {
1686 memcpy (value_contents_all_raw (val) + (idx * typelength),
1687 value_contents_all (elemvec[idx]),
1688 typelength);
1689 }
1690 return val;
1691 }
1692
1693 /* Allocate space to store the array, and then initialize it by
1694 copying in each element. */
1695
1696 val = allocate_value (arraytype);
1697 for (idx = 0; idx < nelem; idx++)
1698 memcpy (value_contents_writeable (val) + (idx * typelength),
1699 value_contents_all (elemvec[idx]),
1700 typelength);
1701 return val;
1702 }
1703
1704 struct value *
1705 value_cstring (char *ptr, int len, struct type *char_type)
1706 {
1707 struct value *val;
1708 int lowbound = current_language->string_lower_bound;
1709 int highbound = len / TYPE_LENGTH (char_type);
1710 struct type *stringtype
1711 = lookup_array_range_type (char_type, lowbound, highbound + lowbound - 1);
1712
1713 val = allocate_value (stringtype);
1714 memcpy (value_contents_raw (val), ptr, len);
1715 return val;
1716 }
1717
1718 /* Create a value for a string constant by allocating space in the
1719 inferior, copying the data into that space, and returning the
1720 address with type TYPE_CODE_STRING. PTR points to the string
1721 constant data; LEN is number of characters.
1722
1723 Note that string types are like array of char types with a lower
1724 bound of zero and an upper bound of LEN - 1. Also note that the
1725 string may contain embedded null bytes. */
1726
1727 struct value *
1728 value_string (char *ptr, int len, struct type *char_type)
1729 {
1730 struct value *val;
1731 int lowbound = current_language->string_lower_bound;
1732 int highbound = len / TYPE_LENGTH (char_type);
1733 struct type *stringtype
1734 = lookup_string_range_type (char_type, lowbound, highbound + lowbound - 1);
1735
1736 val = allocate_value (stringtype);
1737 memcpy (value_contents_raw (val), ptr, len);
1738 return val;
1739 }
1740
1741 struct value *
1742 value_bitstring (char *ptr, int len, struct type *index_type)
1743 {
1744 struct value *val;
1745 struct type *domain_type
1746 = create_range_type (NULL, index_type, 0, len - 1);
1747 struct type *type = create_set_type (NULL, domain_type);
1748
1749 TYPE_CODE (type) = TYPE_CODE_BITSTRING;
1750 val = allocate_value (type);
1751 memcpy (value_contents_raw (val), ptr, TYPE_LENGTH (type));
1752 return val;
1753 }
1754 \f
1755 /* See if we can pass arguments in T2 to a function which takes
1756 arguments of types T1. T1 is a list of NARGS arguments, and T2 is
1757 a NULL-terminated vector. If some arguments need coercion of some
1758 sort, then the coerced values are written into T2. Return value is
1759 0 if the arguments could be matched, or the position at which they
1760 differ if not.
1761
1762 STATICP is nonzero if the T1 argument list came from a static
1763 member function. T2 will still include the ``this'' pointer, but
1764 it will be skipped.
1765
1766 For non-static member functions, we ignore the first argument,
1767 which is the type of the instance variable. This is because we
1768 want to handle calls with objects from derived classes. This is
1769 not entirely correct: we should actually check to make sure that a
1770 requested operation is type secure, shouldn't we? FIXME. */
1771
1772 static int
1773 typecmp (int staticp, int varargs, int nargs,
1774 struct field t1[], struct value *t2[])
1775 {
1776 int i;
1777
1778 if (t2 == 0)
1779 internal_error (__FILE__, __LINE__,
1780 _("typecmp: no argument list"));
1781
1782 /* Skip ``this'' argument if applicable. T2 will always include
1783 THIS. */
1784 if (staticp)
1785 t2 ++;
1786
1787 for (i = 0;
1788 (i < nargs) && TYPE_CODE (t1[i].type) != TYPE_CODE_VOID;
1789 i++)
1790 {
1791 struct type *tt1, *tt2;
1792
1793 if (!t2[i])
1794 return i + 1;
1795
1796 tt1 = check_typedef (t1[i].type);
1797 tt2 = check_typedef (value_type (t2[i]));
1798
1799 if (TYPE_CODE (tt1) == TYPE_CODE_REF
1800 /* We should be doing hairy argument matching, as below. */
1801 && (TYPE_CODE (check_typedef (TYPE_TARGET_TYPE (tt1))) == TYPE_CODE (tt2)))
1802 {
1803 if (TYPE_CODE (tt2) == TYPE_CODE_ARRAY)
1804 t2[i] = value_coerce_array (t2[i]);
1805 else
1806 t2[i] = value_ref (t2[i]);
1807 continue;
1808 }
1809
1810 /* djb - 20000715 - Until the new type structure is in the
1811 place, and we can attempt things like implicit conversions,
1812 we need to do this so you can take something like a map<const
1813 char *>, and properly access map["hello"], because the
1814 argument to [] will be a reference to a pointer to a char,
1815 and the argument will be a pointer to a char. */
1816 while (TYPE_CODE(tt1) == TYPE_CODE_REF
1817 || TYPE_CODE (tt1) == TYPE_CODE_PTR)
1818 {
1819 tt1 = check_typedef( TYPE_TARGET_TYPE(tt1) );
1820 }
1821 while (TYPE_CODE(tt2) == TYPE_CODE_ARRAY
1822 || TYPE_CODE(tt2) == TYPE_CODE_PTR
1823 || TYPE_CODE(tt2) == TYPE_CODE_REF)
1824 {
1825 tt2 = check_typedef (TYPE_TARGET_TYPE(tt2));
1826 }
1827 if (TYPE_CODE (tt1) == TYPE_CODE (tt2))
1828 continue;
1829 /* Array to pointer is a `trivial conversion' according to the
1830 ARM. */
1831
1832 /* We should be doing much hairier argument matching (see
1833 section 13.2 of the ARM), but as a quick kludge, just check
1834 for the same type code. */
1835 if (TYPE_CODE (t1[i].type) != TYPE_CODE (value_type (t2[i])))
1836 return i + 1;
1837 }
1838 if (varargs || t2[i] == NULL)
1839 return 0;
1840 return i + 1;
1841 }
1842
1843 /* Helper function used by value_struct_elt to recurse through
1844 baseclasses. Look for a field NAME in ARG1. Adjust the address of
1845 ARG1 by OFFSET bytes, and search in it assuming it has (class) type
1846 TYPE. If found, return value, else return NULL.
1847
1848 If LOOKING_FOR_BASECLASS, then instead of looking for struct
1849 fields, look for a baseclass named NAME. */
1850
1851 static struct value *
1852 search_struct_field (const char *name, struct value *arg1, int offset,
1853 struct type *type, int looking_for_baseclass)
1854 {
1855 int i;
1856 int nbases;
1857
1858 CHECK_TYPEDEF (type);
1859 nbases = TYPE_N_BASECLASSES (type);
1860
1861 if (!looking_for_baseclass)
1862 for (i = TYPE_NFIELDS (type) - 1; i >= nbases; i--)
1863 {
1864 char *t_field_name = TYPE_FIELD_NAME (type, i);
1865
1866 if (t_field_name && (strcmp_iw (t_field_name, name) == 0))
1867 {
1868 struct value *v;
1869
1870 if (field_is_static (&TYPE_FIELD (type, i)))
1871 {
1872 v = value_static_field (type, i);
1873 if (v == 0)
1874 error (_("field %s is nonexistent or has been optimized out"),
1875 name);
1876 }
1877 else
1878 {
1879 v = value_primitive_field (arg1, offset, i, type);
1880 if (v == 0)
1881 error (_("there is no field named %s"), name);
1882 }
1883 return v;
1884 }
1885
1886 if (t_field_name
1887 && (t_field_name[0] == '\0'
1888 || (TYPE_CODE (type) == TYPE_CODE_UNION
1889 && (strcmp_iw (t_field_name, "else") == 0))))
1890 {
1891 struct type *field_type = TYPE_FIELD_TYPE (type, i);
1892
1893 if (TYPE_CODE (field_type) == TYPE_CODE_UNION
1894 || TYPE_CODE (field_type) == TYPE_CODE_STRUCT)
1895 {
1896 /* Look for a match through the fields of an anonymous
1897 union, or anonymous struct. C++ provides anonymous
1898 unions.
1899
1900 In the GNU Chill (now deleted from GDB)
1901 implementation of variant record types, each
1902 <alternative field> has an (anonymous) union type,
1903 each member of the union represents a <variant
1904 alternative>. Each <variant alternative> is
1905 represented as a struct, with a member for each
1906 <variant field>. */
1907
1908 struct value *v;
1909 int new_offset = offset;
1910
1911 /* This is pretty gross. In G++, the offset in an
1912 anonymous union is relative to the beginning of the
1913 enclosing struct. In the GNU Chill (now deleted
1914 from GDB) implementation of variant records, the
1915 bitpos is zero in an anonymous union field, so we
1916 have to add the offset of the union here. */
1917 if (TYPE_CODE (field_type) == TYPE_CODE_STRUCT
1918 || (TYPE_NFIELDS (field_type) > 0
1919 && TYPE_FIELD_BITPOS (field_type, 0) == 0))
1920 new_offset += TYPE_FIELD_BITPOS (type, i) / 8;
1921
1922 v = search_struct_field (name, arg1, new_offset,
1923 field_type,
1924 looking_for_baseclass);
1925 if (v)
1926 return v;
1927 }
1928 }
1929 }
1930
1931 for (i = 0; i < nbases; i++)
1932 {
1933 struct value *v;
1934 struct type *basetype = check_typedef (TYPE_BASECLASS (type, i));
1935 /* If we are looking for baseclasses, this is what we get when
1936 we hit them. But it could happen that the base part's member
1937 name is not yet filled in. */
1938 int found_baseclass = (looking_for_baseclass
1939 && TYPE_BASECLASS_NAME (type, i) != NULL
1940 && (strcmp_iw (name,
1941 TYPE_BASECLASS_NAME (type,
1942 i)) == 0));
1943
1944 if (BASETYPE_VIA_VIRTUAL (type, i))
1945 {
1946 int boffset;
1947 struct value *v2;
1948
1949 boffset = baseclass_offset (type, i,
1950 value_contents (arg1) + offset,
1951 value_address (arg1)
1952 + value_embedded_offset (arg1)
1953 + offset);
1954 if (boffset == -1)
1955 error (_("virtual baseclass botch"));
1956
1957 /* The virtual base class pointer might have been clobbered
1958 by the user program. Make sure that it still points to a
1959 valid memory location. */
1960
1961 boffset += value_embedded_offset (arg1) + offset;
1962 if (boffset < 0
1963 || boffset >= TYPE_LENGTH (value_enclosing_type (arg1)))
1964 {
1965 CORE_ADDR base_addr;
1966
1967 v2 = allocate_value (basetype);
1968 base_addr = value_address (arg1) + boffset;
1969 if (target_read_memory (base_addr,
1970 value_contents_raw (v2),
1971 TYPE_LENGTH (basetype)) != 0)
1972 error (_("virtual baseclass botch"));
1973 VALUE_LVAL (v2) = lval_memory;
1974 set_value_address (v2, base_addr);
1975 }
1976 else
1977 {
1978 v2 = value_copy (arg1);
1979 deprecated_set_value_type (v2, basetype);
1980 set_value_embedded_offset (v2, boffset);
1981 }
1982
1983 if (found_baseclass)
1984 return v2;
1985 v = search_struct_field (name, v2, 0,
1986 TYPE_BASECLASS (type, i),
1987 looking_for_baseclass);
1988 }
1989 else if (found_baseclass)
1990 v = value_primitive_field (arg1, offset, i, type);
1991 else
1992 v = search_struct_field (name, arg1,
1993 offset + TYPE_BASECLASS_BITPOS (type,
1994 i) / 8,
1995 basetype, looking_for_baseclass);
1996 if (v)
1997 return v;
1998 }
1999 return NULL;
2000 }
2001
2002 /* Helper function used by value_struct_elt to recurse through
2003 baseclasses. Look for a field NAME in ARG1. Adjust the address of
2004 ARG1 by OFFSET bytes, and search in it assuming it has (class) type
2005 TYPE.
2006
2007 If found, return value, else if name matched and args not return
2008 (value) -1, else return NULL. */
2009
2010 static struct value *
2011 search_struct_method (const char *name, struct value **arg1p,
2012 struct value **args, int offset,
2013 int *static_memfuncp, struct type *type)
2014 {
2015 int i;
2016 struct value *v;
2017 int name_matched = 0;
2018 char dem_opname[64];
2019
2020 CHECK_TYPEDEF (type);
2021 for (i = TYPE_NFN_FIELDS (type) - 1; i >= 0; i--)
2022 {
2023 char *t_field_name = TYPE_FN_FIELDLIST_NAME (type, i);
2024
2025 /* FIXME! May need to check for ARM demangling here */
2026 if (strncmp (t_field_name, "__", 2) == 0 ||
2027 strncmp (t_field_name, "op", 2) == 0 ||
2028 strncmp (t_field_name, "type", 4) == 0)
2029 {
2030 if (cplus_demangle_opname (t_field_name, dem_opname, DMGL_ANSI))
2031 t_field_name = dem_opname;
2032 else if (cplus_demangle_opname (t_field_name, dem_opname, 0))
2033 t_field_name = dem_opname;
2034 }
2035 if (t_field_name && (strcmp_iw (t_field_name, name) == 0))
2036 {
2037 int j = TYPE_FN_FIELDLIST_LENGTH (type, i) - 1;
2038 struct fn_field *f = TYPE_FN_FIELDLIST1 (type, i);
2039
2040 name_matched = 1;
2041 check_stub_method_group (type, i);
2042 if (j > 0 && args == 0)
2043 error (_("cannot resolve overloaded method `%s': no arguments supplied"), name);
2044 else if (j == 0 && args == 0)
2045 {
2046 v = value_fn_field (arg1p, f, j, type, offset);
2047 if (v != NULL)
2048 return v;
2049 }
2050 else
2051 while (j >= 0)
2052 {
2053 if (!typecmp (TYPE_FN_FIELD_STATIC_P (f, j),
2054 TYPE_VARARGS (TYPE_FN_FIELD_TYPE (f, j)),
2055 TYPE_NFIELDS (TYPE_FN_FIELD_TYPE (f, j)),
2056 TYPE_FN_FIELD_ARGS (f, j), args))
2057 {
2058 if (TYPE_FN_FIELD_VIRTUAL_P (f, j))
2059 return value_virtual_fn_field (arg1p, f, j,
2060 type, offset);
2061 if (TYPE_FN_FIELD_STATIC_P (f, j)
2062 && static_memfuncp)
2063 *static_memfuncp = 1;
2064 v = value_fn_field (arg1p, f, j, type, offset);
2065 if (v != NULL)
2066 return v;
2067 }
2068 j--;
2069 }
2070 }
2071 }
2072
2073 for (i = TYPE_N_BASECLASSES (type) - 1; i >= 0; i--)
2074 {
2075 int base_offset;
2076
2077 if (BASETYPE_VIA_VIRTUAL (type, i))
2078 {
2079 struct type *baseclass = check_typedef (TYPE_BASECLASS (type, i));
2080 const gdb_byte *base_valaddr;
2081
2082 /* The virtual base class pointer might have been
2083 clobbered by the user program. Make sure that it
2084 still points to a valid memory location. */
2085
2086 if (offset < 0 || offset >= TYPE_LENGTH (type))
2087 {
2088 gdb_byte *tmp = alloca (TYPE_LENGTH (baseclass));
2089
2090 if (target_read_memory (value_address (*arg1p) + offset,
2091 tmp, TYPE_LENGTH (baseclass)) != 0)
2092 error (_("virtual baseclass botch"));
2093 base_valaddr = tmp;
2094 }
2095 else
2096 base_valaddr = value_contents (*arg1p) + offset;
2097
2098 base_offset = baseclass_offset (type, i, base_valaddr,
2099 value_address (*arg1p) + offset);
2100 if (base_offset == -1)
2101 error (_("virtual baseclass botch"));
2102 }
2103 else
2104 {
2105 base_offset = TYPE_BASECLASS_BITPOS (type, i) / 8;
2106 }
2107 v = search_struct_method (name, arg1p, args, base_offset + offset,
2108 static_memfuncp, TYPE_BASECLASS (type, i));
2109 if (v == (struct value *) - 1)
2110 {
2111 name_matched = 1;
2112 }
2113 else if (v)
2114 {
2115 /* FIXME-bothner: Why is this commented out? Why is it here? */
2116 /* *arg1p = arg1_tmp; */
2117 return v;
2118 }
2119 }
2120 if (name_matched)
2121 return (struct value *) - 1;
2122 else
2123 return NULL;
2124 }
2125
2126 /* Given *ARGP, a value of type (pointer to a)* structure/union,
2127 extract the component named NAME from the ultimate target
2128 structure/union and return it as a value with its appropriate type.
2129 ERR is used in the error message if *ARGP's type is wrong.
2130
2131 C++: ARGS is a list of argument types to aid in the selection of
2132 an appropriate method. Also, handle derived types.
2133
2134 STATIC_MEMFUNCP, if non-NULL, points to a caller-supplied location
2135 where the truthvalue of whether the function that was resolved was
2136 a static member function or not is stored.
2137
2138 ERR is an error message to be printed in case the field is not
2139 found. */
2140
2141 struct value *
2142 value_struct_elt (struct value **argp, struct value **args,
2143 const char *name, int *static_memfuncp, const char *err)
2144 {
2145 struct type *t;
2146 struct value *v;
2147
2148 *argp = coerce_array (*argp);
2149
2150 t = check_typedef (value_type (*argp));
2151
2152 /* Follow pointers until we get to a non-pointer. */
2153
2154 while (TYPE_CODE (t) == TYPE_CODE_PTR || TYPE_CODE (t) == TYPE_CODE_REF)
2155 {
2156 *argp = value_ind (*argp);
2157 /* Don't coerce fn pointer to fn and then back again! */
2158 if (TYPE_CODE (value_type (*argp)) != TYPE_CODE_FUNC)
2159 *argp = coerce_array (*argp);
2160 t = check_typedef (value_type (*argp));
2161 }
2162
2163 if (TYPE_CODE (t) != TYPE_CODE_STRUCT
2164 && TYPE_CODE (t) != TYPE_CODE_UNION)
2165 error (_("Attempt to extract a component of a value that is not a %s."), err);
2166
2167 /* Assume it's not, unless we see that it is. */
2168 if (static_memfuncp)
2169 *static_memfuncp = 0;
2170
2171 if (!args)
2172 {
2173 /* if there are no arguments ...do this... */
2174
2175 /* Try as a field first, because if we succeed, there is less
2176 work to be done. */
2177 v = search_struct_field (name, *argp, 0, t, 0);
2178 if (v)
2179 return v;
2180
2181 /* C++: If it was not found as a data field, then try to
2182 return it as a pointer to a method. */
2183 v = search_struct_method (name, argp, args, 0,
2184 static_memfuncp, t);
2185
2186 if (v == (struct value *) - 1)
2187 error (_("Cannot take address of method %s."), name);
2188 else if (v == 0)
2189 {
2190 if (TYPE_NFN_FIELDS (t))
2191 error (_("There is no member or method named %s."), name);
2192 else
2193 error (_("There is no member named %s."), name);
2194 }
2195 return v;
2196 }
2197
2198 v = search_struct_method (name, argp, args, 0,
2199 static_memfuncp, t);
2200
2201 if (v == (struct value *) - 1)
2202 {
2203 error (_("One of the arguments you tried to pass to %s could not be converted to what the function wants."), name);
2204 }
2205 else if (v == 0)
2206 {
2207 /* See if user tried to invoke data as function. If so, hand it
2208 back. If it's not callable (i.e., a pointer to function),
2209 gdb should give an error. */
2210 v = search_struct_field (name, *argp, 0, t, 0);
2211 /* If we found an ordinary field, then it is not a method call.
2212 So, treat it as if it were a static member function. */
2213 if (v && static_memfuncp)
2214 *static_memfuncp = 1;
2215 }
2216
2217 if (!v)
2218 error (_("Structure has no component named %s."), name);
2219 return v;
2220 }
2221
2222 /* Search through the methods of an object (and its bases) to find a
2223 specified method. Return the pointer to the fn_field list of
2224 overloaded instances.
2225
2226 Helper function for value_find_oload_list.
2227 ARGP is a pointer to a pointer to a value (the object).
2228 METHOD is a string containing the method name.
2229 OFFSET is the offset within the value.
2230 TYPE is the assumed type of the object.
2231 NUM_FNS is the number of overloaded instances.
2232 BASETYPE is set to the actual type of the subobject where the
2233 method is found.
2234 BOFFSET is the offset of the base subobject where the method is found.
2235 */
2236
2237 static struct fn_field *
2238 find_method_list (struct value **argp, const char *method,
2239 int offset, struct type *type, int *num_fns,
2240 struct type **basetype, int *boffset)
2241 {
2242 int i;
2243 struct fn_field *f;
2244 CHECK_TYPEDEF (type);
2245
2246 *num_fns = 0;
2247
2248 /* First check in object itself. */
2249 for (i = TYPE_NFN_FIELDS (type) - 1; i >= 0; i--)
2250 {
2251 /* pai: FIXME What about operators and type conversions? */
2252 char *fn_field_name = TYPE_FN_FIELDLIST_NAME (type, i);
2253
2254 if (fn_field_name && (strcmp_iw (fn_field_name, method) == 0))
2255 {
2256 int len = TYPE_FN_FIELDLIST_LENGTH (type, i);
2257 struct fn_field *f = TYPE_FN_FIELDLIST1 (type, i);
2258
2259 *num_fns = len;
2260 *basetype = type;
2261 *boffset = offset;
2262
2263 /* Resolve any stub methods. */
2264 check_stub_method_group (type, i);
2265
2266 return f;
2267 }
2268 }
2269
2270 /* Not found in object, check in base subobjects. */
2271 for (i = TYPE_N_BASECLASSES (type) - 1; i >= 0; i--)
2272 {
2273 int base_offset;
2274
2275 if (BASETYPE_VIA_VIRTUAL (type, i))
2276 {
2277 base_offset = value_offset (*argp) + offset;
2278 base_offset = baseclass_offset (type, i,
2279 value_contents (*argp) + base_offset,
2280 value_address (*argp) + base_offset);
2281 if (base_offset == -1)
2282 error (_("virtual baseclass botch"));
2283 }
2284 else /* Non-virtual base, simply use bit position from debug
2285 info. */
2286 {
2287 base_offset = TYPE_BASECLASS_BITPOS (type, i) / 8;
2288 }
2289 f = find_method_list (argp, method, base_offset + offset,
2290 TYPE_BASECLASS (type, i), num_fns,
2291 basetype, boffset);
2292 if (f)
2293 return f;
2294 }
2295 return NULL;
2296 }
2297
2298 /* Return the list of overloaded methods of a specified name.
2299
2300 ARGP is a pointer to a pointer to a value (the object).
2301 METHOD is the method name.
2302 OFFSET is the offset within the value contents.
2303 NUM_FNS is the number of overloaded instances.
2304 BASETYPE is set to the type of the base subobject that defines the
2305 method.
2306 BOFFSET is the offset of the base subobject which defines the method.
2307 */
2308
2309 struct fn_field *
2310 value_find_oload_method_list (struct value **argp, const char *method,
2311 int offset, int *num_fns,
2312 struct type **basetype, int *boffset)
2313 {
2314 struct type *t;
2315
2316 t = check_typedef (value_type (*argp));
2317
2318 /* Code snarfed from value_struct_elt. */
2319 while (TYPE_CODE (t) == TYPE_CODE_PTR || TYPE_CODE (t) == TYPE_CODE_REF)
2320 {
2321 *argp = value_ind (*argp);
2322 /* Don't coerce fn pointer to fn and then back again! */
2323 if (TYPE_CODE (value_type (*argp)) != TYPE_CODE_FUNC)
2324 *argp = coerce_array (*argp);
2325 t = check_typedef (value_type (*argp));
2326 }
2327
2328 if (TYPE_CODE (t) != TYPE_CODE_STRUCT
2329 && TYPE_CODE (t) != TYPE_CODE_UNION)
2330 error (_("Attempt to extract a component of a value that is not a struct or union"));
2331
2332 return find_method_list (argp, method, 0, t, num_fns,
2333 basetype, boffset);
2334 }
2335
2336 /* Given an array of argument types (ARGTYPES) (which includes an
2337 entry for "this" in the case of C++ methods), the number of
2338 arguments NARGS, the NAME of a function whether it's a method or
2339 not (METHOD), and the degree of laxness (LAX) in conforming to
2340 overload resolution rules in ANSI C++, find the best function that
2341 matches on the argument types according to the overload resolution
2342 rules.
2343
2344 METHOD can be one of three values:
2345 NON_METHOD for non-member functions.
2346 METHOD: for member functions.
2347 BOTH: used for overload resolution of operators where the
2348 candidates are expected to be either member or non member
2349 functions. In this case the first argument ARGTYPES
2350 (representing 'this') is expected to be a reference to the
2351 target object, and will be dereferenced when attempting the
2352 non-member search.
2353
2354 In the case of class methods, the parameter OBJ is an object value
2355 in which to search for overloaded methods.
2356
2357 In the case of non-method functions, the parameter FSYM is a symbol
2358 corresponding to one of the overloaded functions.
2359
2360 Return value is an integer: 0 -> good match, 10 -> debugger applied
2361 non-standard coercions, 100 -> incompatible.
2362
2363 If a method is being searched for, VALP will hold the value.
2364 If a non-method is being searched for, SYMP will hold the symbol
2365 for it.
2366
2367 If a method is being searched for, and it is a static method,
2368 then STATICP will point to a non-zero value.
2369
2370 If NO_ADL argument dependent lookup is disabled. This is used to prevent
2371 ADL overload candidates when performing overload resolution for a fully
2372 qualified name.
2373
2374 Note: This function does *not* check the value of
2375 overload_resolution. Caller must check it to see whether overload
2376 resolution is permitted.
2377 */
2378
2379 int
2380 find_overload_match (struct type **arg_types, int nargs,
2381 const char *name, enum oload_search_type method,
2382 int lax, struct value **objp, struct symbol *fsym,
2383 struct value **valp, struct symbol **symp,
2384 int *staticp, const int no_adl)
2385 {
2386 struct value *obj = (objp ? *objp : NULL);
2387 /* Index of best overloaded function. */
2388 int func_oload_champ = -1;
2389 int method_oload_champ = -1;
2390
2391 /* The measure for the current best match. */
2392 struct badness_vector *method_badness = NULL;
2393 struct badness_vector *func_badness = NULL;
2394
2395 struct value *temp = obj;
2396 /* For methods, the list of overloaded methods. */
2397 struct fn_field *fns_ptr = NULL;
2398 /* For non-methods, the list of overloaded function symbols. */
2399 struct symbol **oload_syms = NULL;
2400 /* Number of overloaded instances being considered. */
2401 int num_fns = 0;
2402 struct type *basetype = NULL;
2403 int boffset;
2404
2405 struct cleanup *all_cleanups = make_cleanup (null_cleanup, NULL);
2406
2407 const char *obj_type_name = NULL;
2408 const char *func_name = NULL;
2409 enum oload_classification match_quality;
2410 enum oload_classification method_match_quality = INCOMPATIBLE;
2411 enum oload_classification func_match_quality = INCOMPATIBLE;
2412
2413 /* Get the list of overloaded methods or functions. */
2414 if (method == METHOD || method == BOTH)
2415 {
2416 gdb_assert (obj);
2417
2418 /* OBJ may be a pointer value rather than the object itself. */
2419 obj = coerce_ref (obj);
2420 while (TYPE_CODE (check_typedef (value_type (obj))) == TYPE_CODE_PTR)
2421 obj = coerce_ref (value_ind (obj));
2422 obj_type_name = TYPE_NAME (value_type (obj));
2423
2424 /* First check whether this is a data member, e.g. a pointer to
2425 a function. */
2426 if (TYPE_CODE (check_typedef (value_type (obj))) == TYPE_CODE_STRUCT)
2427 {
2428 *valp = search_struct_field (name, obj, 0,
2429 check_typedef (value_type (obj)), 0);
2430 if (*valp)
2431 {
2432 *staticp = 1;
2433 return 0;
2434 }
2435 }
2436
2437 /* Retrieve the list of methods with the name NAME. */
2438 fns_ptr = value_find_oload_method_list (&temp, name,
2439 0, &num_fns,
2440 &basetype, &boffset);
2441 /* If this is a method only search, and no methods were found
2442 the search has faild. */
2443 if (method == METHOD && (!fns_ptr || !num_fns))
2444 error (_("Couldn't find method %s%s%s"),
2445 obj_type_name,
2446 (obj_type_name && *obj_type_name) ? "::" : "",
2447 name);
2448 /* If we are dealing with stub method types, they should have
2449 been resolved by find_method_list via
2450 value_find_oload_method_list above. */
2451 if (fns_ptr)
2452 {
2453 gdb_assert (TYPE_DOMAIN_TYPE (fns_ptr[0].type) != NULL);
2454 method_oload_champ = find_oload_champ (arg_types, nargs, method,
2455 num_fns, fns_ptr,
2456 oload_syms, &method_badness);
2457
2458 method_match_quality =
2459 classify_oload_match (method_badness, nargs,
2460 oload_method_static (method, fns_ptr,
2461 method_oload_champ));
2462
2463 make_cleanup (xfree, method_badness);
2464 }
2465
2466 }
2467
2468 if (method == NON_METHOD || method == BOTH)
2469 {
2470 const char *qualified_name = NULL;
2471
2472 /* If the the overload match is being search for both
2473 as a method and non member function, the first argument
2474 must now be dereferenced. */
2475 if (method == BOTH)
2476 arg_types[0] = TYPE_TARGET_TYPE (arg_types[0]);
2477
2478 if (fsym)
2479 {
2480 qualified_name = SYMBOL_NATURAL_NAME (fsym);
2481
2482 /* If we have a function with a C++ name, try to extract just
2483 the function part. Do not try this for non-functions (e.g.
2484 function pointers). */
2485 if (qualified_name
2486 && TYPE_CODE (check_typedef (SYMBOL_TYPE (fsym))) == TYPE_CODE_FUNC)
2487 {
2488 char *temp;
2489
2490 temp = cp_func_name (qualified_name);
2491
2492 /* If cp_func_name did not remove anything, the name of the
2493 symbol did not include scope or argument types - it was
2494 probably a C-style function. */
2495 if (temp)
2496 {
2497 make_cleanup (xfree, temp);
2498 if (strcmp (temp, qualified_name) == 0)
2499 func_name = NULL;
2500 else
2501 func_name = temp;
2502 }
2503 }
2504 }
2505 else
2506 {
2507 func_name = name;
2508 qualified_name = name;
2509 }
2510
2511 /* If there was no C++ name, this must be a C-style function or
2512 not a function at all. Just return the same symbol. Do the
2513 same if cp_func_name fails for some reason. */
2514 if (func_name == NULL)
2515 {
2516 *symp = fsym;
2517 return 0;
2518 }
2519
2520 func_oload_champ = find_oload_champ_namespace (arg_types, nargs,
2521 func_name,
2522 qualified_name,
2523 &oload_syms,
2524 &func_badness,
2525 no_adl);
2526
2527 if (func_oload_champ >= 0)
2528 func_match_quality = classify_oload_match (func_badness, nargs, 0);
2529
2530 make_cleanup (xfree, oload_syms);
2531 make_cleanup (xfree, func_badness);
2532 }
2533
2534 /* Did we find a match ? */
2535 if (method_oload_champ == -1 && func_oload_champ == -1)
2536 error (_("No symbol \"%s\" in current context."), name);
2537
2538 /* If we have found both a method match and a function
2539 match, find out which one is better, and calculate match
2540 quality. */
2541 if (method_oload_champ >= 0 && func_oload_champ >= 0)
2542 {
2543 switch (compare_badness (func_badness, method_badness))
2544 {
2545 case 0: /* Top two contenders are equally good. */
2546 /* FIXME: GDB does not support the general ambiguous
2547 case. All candidates should be collected and presented
2548 the the user. */
2549 error (_("Ambiguous overload resolution"));
2550 break;
2551 case 1: /* Incomparable top contenders. */
2552 /* This is an error incompatible candidates
2553 should not have been proposed. */
2554 error (_("Internal error: incompatible overload candidates proposed"));
2555 break;
2556 case 2: /* Function champion. */
2557 method_oload_champ = -1;
2558 match_quality = func_match_quality;
2559 break;
2560 case 3: /* Method champion. */
2561 func_oload_champ = -1;
2562 match_quality = method_match_quality;
2563 break;
2564 default:
2565 error (_("Internal error: unexpected overload comparison result"));
2566 break;
2567 }
2568 }
2569 else
2570 {
2571 /* We have either a method match or a function match. */
2572 if (method_oload_champ >= 0)
2573 match_quality = method_match_quality;
2574 else
2575 match_quality = func_match_quality;
2576 }
2577
2578 if (match_quality == INCOMPATIBLE)
2579 {
2580 if (method == METHOD)
2581 error (_("Cannot resolve method %s%s%s to any overloaded instance"),
2582 obj_type_name,
2583 (obj_type_name && *obj_type_name) ? "::" : "",
2584 name);
2585 else
2586 error (_("Cannot resolve function %s to any overloaded instance"),
2587 func_name);
2588 }
2589 else if (match_quality == NON_STANDARD)
2590 {
2591 if (method == METHOD)
2592 warning (_("Using non-standard conversion to match method %s%s%s to supplied arguments"),
2593 obj_type_name,
2594 (obj_type_name && *obj_type_name) ? "::" : "",
2595 name);
2596 else
2597 warning (_("Using non-standard conversion to match function %s to supplied arguments"),
2598 func_name);
2599 }
2600
2601 if (staticp != NULL)
2602 *staticp = oload_method_static (method, fns_ptr, method_oload_champ);
2603
2604 if (method_oload_champ >= 0)
2605 {
2606 if (TYPE_FN_FIELD_VIRTUAL_P (fns_ptr, method_oload_champ))
2607 *valp = value_virtual_fn_field (&temp, fns_ptr, method_oload_champ,
2608 basetype, boffset);
2609 else
2610 *valp = value_fn_field (&temp, fns_ptr, method_oload_champ,
2611 basetype, boffset);
2612 }
2613 else
2614 *symp = oload_syms[func_oload_champ];
2615
2616 if (objp)
2617 {
2618 struct type *temp_type = check_typedef (value_type (temp));
2619 struct type *obj_type = check_typedef (value_type (*objp));
2620
2621 if (TYPE_CODE (temp_type) != TYPE_CODE_PTR
2622 && (TYPE_CODE (obj_type) == TYPE_CODE_PTR
2623 || TYPE_CODE (obj_type) == TYPE_CODE_REF))
2624 {
2625 temp = value_addr (temp);
2626 }
2627 *objp = temp;
2628 }
2629
2630 do_cleanups (all_cleanups);
2631
2632 switch (match_quality)
2633 {
2634 case INCOMPATIBLE:
2635 return 100;
2636 case NON_STANDARD:
2637 return 10;
2638 default: /* STANDARD */
2639 return 0;
2640 }
2641 }
2642
2643 /* Find the best overload match, searching for FUNC_NAME in namespaces
2644 contained in QUALIFIED_NAME until it either finds a good match or
2645 runs out of namespaces. It stores the overloaded functions in
2646 *OLOAD_SYMS, and the badness vector in *OLOAD_CHAMP_BV. The
2647 calling function is responsible for freeing *OLOAD_SYMS and
2648 *OLOAD_CHAMP_BV. If NO_ADL, argument dependent lookup is not
2649 performned. */
2650
2651 static int
2652 find_oload_champ_namespace (struct type **arg_types, int nargs,
2653 const char *func_name,
2654 const char *qualified_name,
2655 struct symbol ***oload_syms,
2656 struct badness_vector **oload_champ_bv,
2657 const int no_adl)
2658 {
2659 int oload_champ;
2660
2661 find_oload_champ_namespace_loop (arg_types, nargs,
2662 func_name,
2663 qualified_name, 0,
2664 oload_syms, oload_champ_bv,
2665 &oload_champ,
2666 no_adl);
2667
2668 return oload_champ;
2669 }
2670
2671 /* Helper function for find_oload_champ_namespace; NAMESPACE_LEN is
2672 how deep we've looked for namespaces, and the champ is stored in
2673 OLOAD_CHAMP. The return value is 1 if the champ is a good one, 0
2674 if it isn't. Other arguments are the same as in
2675 find_oload_champ_namespace
2676
2677 It is the caller's responsibility to free *OLOAD_SYMS and
2678 *OLOAD_CHAMP_BV. */
2679
2680 static int
2681 find_oload_champ_namespace_loop (struct type **arg_types, int nargs,
2682 const char *func_name,
2683 const char *qualified_name,
2684 int namespace_len,
2685 struct symbol ***oload_syms,
2686 struct badness_vector **oload_champ_bv,
2687 int *oload_champ,
2688 const int no_adl)
2689 {
2690 int next_namespace_len = namespace_len;
2691 int searched_deeper = 0;
2692 int num_fns = 0;
2693 struct cleanup *old_cleanups;
2694 int new_oload_champ;
2695 struct symbol **new_oload_syms;
2696 struct badness_vector *new_oload_champ_bv;
2697 char *new_namespace;
2698
2699 if (next_namespace_len != 0)
2700 {
2701 gdb_assert (qualified_name[next_namespace_len] == ':');
2702 next_namespace_len += 2;
2703 }
2704 next_namespace_len +=
2705 cp_find_first_component (qualified_name + next_namespace_len);
2706
2707 /* Initialize these to values that can safely be xfree'd. */
2708 *oload_syms = NULL;
2709 *oload_champ_bv = NULL;
2710
2711 /* First, see if we have a deeper namespace we can search in.
2712 If we get a good match there, use it. */
2713
2714 if (qualified_name[next_namespace_len] == ':')
2715 {
2716 searched_deeper = 1;
2717
2718 if (find_oload_champ_namespace_loop (arg_types, nargs,
2719 func_name, qualified_name,
2720 next_namespace_len,
2721 oload_syms, oload_champ_bv,
2722 oload_champ, no_adl))
2723 {
2724 return 1;
2725 }
2726 };
2727
2728 /* If we reach here, either we're in the deepest namespace or we
2729 didn't find a good match in a deeper namespace. But, in the
2730 latter case, we still have a bad match in a deeper namespace;
2731 note that we might not find any match at all in the current
2732 namespace. (There's always a match in the deepest namespace,
2733 because this overload mechanism only gets called if there's a
2734 function symbol to start off with.) */
2735
2736 old_cleanups = make_cleanup (xfree, *oload_syms);
2737 make_cleanup (xfree, *oload_champ_bv);
2738 new_namespace = alloca (namespace_len + 1);
2739 strncpy (new_namespace, qualified_name, namespace_len);
2740 new_namespace[namespace_len] = '\0';
2741 new_oload_syms = make_symbol_overload_list (func_name,
2742 new_namespace);
2743
2744 /* If we have reached the deepest level perform argument
2745 determined lookup. */
2746 if (!searched_deeper && !no_adl)
2747 make_symbol_overload_list_adl (arg_types, nargs, func_name);
2748
2749 while (new_oload_syms[num_fns])
2750 ++num_fns;
2751
2752 new_oload_champ = find_oload_champ (arg_types, nargs, 0, num_fns,
2753 NULL, new_oload_syms,
2754 &new_oload_champ_bv);
2755
2756 /* Case 1: We found a good match. Free earlier matches (if any),
2757 and return it. Case 2: We didn't find a good match, but we're
2758 not the deepest function. Then go with the bad match that the
2759 deeper function found. Case 3: We found a bad match, and we're
2760 the deepest function. Then return what we found, even though
2761 it's a bad match. */
2762
2763 if (new_oload_champ != -1
2764 && classify_oload_match (new_oload_champ_bv, nargs, 0) == STANDARD)
2765 {
2766 *oload_syms = new_oload_syms;
2767 *oload_champ = new_oload_champ;
2768 *oload_champ_bv = new_oload_champ_bv;
2769 do_cleanups (old_cleanups);
2770 return 1;
2771 }
2772 else if (searched_deeper)
2773 {
2774 xfree (new_oload_syms);
2775 xfree (new_oload_champ_bv);
2776 discard_cleanups (old_cleanups);
2777 return 0;
2778 }
2779 else
2780 {
2781 *oload_syms = new_oload_syms;
2782 *oload_champ = new_oload_champ;
2783 *oload_champ_bv = new_oload_champ_bv;
2784 do_cleanups (old_cleanups);
2785 return 0;
2786 }
2787 }
2788
2789 /* Look for a function to take NARGS args of types ARG_TYPES. Find
2790 the best match from among the overloaded methods or functions
2791 (depending on METHOD) given by FNS_PTR or OLOAD_SYMS, respectively.
2792 The number of methods/functions in the list is given by NUM_FNS.
2793 Return the index of the best match; store an indication of the
2794 quality of the match in OLOAD_CHAMP_BV.
2795
2796 It is the caller's responsibility to free *OLOAD_CHAMP_BV. */
2797
2798 static int
2799 find_oload_champ (struct type **arg_types, int nargs, int method,
2800 int num_fns, struct fn_field *fns_ptr,
2801 struct symbol **oload_syms,
2802 struct badness_vector **oload_champ_bv)
2803 {
2804 int ix;
2805 /* A measure of how good an overloaded instance is. */
2806 struct badness_vector *bv;
2807 /* Index of best overloaded function. */
2808 int oload_champ = -1;
2809 /* Current ambiguity state for overload resolution. */
2810 int oload_ambiguous = 0;
2811 /* 0 => no ambiguity, 1 => two good funcs, 2 => incomparable funcs. */
2812
2813 *oload_champ_bv = NULL;
2814
2815 /* Consider each candidate in turn. */
2816 for (ix = 0; ix < num_fns; ix++)
2817 {
2818 int jj;
2819 int static_offset = oload_method_static (method, fns_ptr, ix);
2820 int nparms;
2821 struct type **parm_types;
2822
2823 if (method)
2824 {
2825 nparms = TYPE_NFIELDS (TYPE_FN_FIELD_TYPE (fns_ptr, ix));
2826 }
2827 else
2828 {
2829 /* If it's not a method, this is the proper place. */
2830 nparms = TYPE_NFIELDS (SYMBOL_TYPE (oload_syms[ix]));
2831 }
2832
2833 /* Prepare array of parameter types. */
2834 parm_types = (struct type **)
2835 xmalloc (nparms * (sizeof (struct type *)));
2836 for (jj = 0; jj < nparms; jj++)
2837 parm_types[jj] = (method
2838 ? (TYPE_FN_FIELD_ARGS (fns_ptr, ix)[jj].type)
2839 : TYPE_FIELD_TYPE (SYMBOL_TYPE (oload_syms[ix]),
2840 jj));
2841
2842 /* Compare parameter types to supplied argument types. Skip
2843 THIS for static methods. */
2844 bv = rank_function (parm_types, nparms,
2845 arg_types + static_offset,
2846 nargs - static_offset);
2847
2848 if (!*oload_champ_bv)
2849 {
2850 *oload_champ_bv = bv;
2851 oload_champ = 0;
2852 }
2853 else /* See whether current candidate is better or worse than
2854 previous best. */
2855 switch (compare_badness (bv, *oload_champ_bv))
2856 {
2857 case 0: /* Top two contenders are equally good. */
2858 oload_ambiguous = 1;
2859 break;
2860 case 1: /* Incomparable top contenders. */
2861 oload_ambiguous = 2;
2862 break;
2863 case 2: /* New champion, record details. */
2864 *oload_champ_bv = bv;
2865 oload_ambiguous = 0;
2866 oload_champ = ix;
2867 break;
2868 case 3:
2869 default:
2870 break;
2871 }
2872 xfree (parm_types);
2873 if (overload_debug)
2874 {
2875 if (method)
2876 fprintf_filtered (gdb_stderr,
2877 "Overloaded method instance %s, # of parms %d\n",
2878 fns_ptr[ix].physname, nparms);
2879 else
2880 fprintf_filtered (gdb_stderr,
2881 "Overloaded function instance %s # of parms %d\n",
2882 SYMBOL_DEMANGLED_NAME (oload_syms[ix]),
2883 nparms);
2884 for (jj = 0; jj < nargs - static_offset; jj++)
2885 fprintf_filtered (gdb_stderr,
2886 "...Badness @ %d : %d\n",
2887 jj, bv->rank[jj]);
2888 fprintf_filtered (gdb_stderr,
2889 "Overload resolution champion is %d, ambiguous? %d\n",
2890 oload_champ, oload_ambiguous);
2891 }
2892 }
2893
2894 return oload_champ;
2895 }
2896
2897 /* Return 1 if we're looking at a static method, 0 if we're looking at
2898 a non-static method or a function that isn't a method. */
2899
2900 static int
2901 oload_method_static (int method, struct fn_field *fns_ptr, int index)
2902 {
2903 if (method && fns_ptr && index >= 0
2904 && TYPE_FN_FIELD_STATIC_P (fns_ptr, index))
2905 return 1;
2906 else
2907 return 0;
2908 }
2909
2910 /* Check how good an overload match OLOAD_CHAMP_BV represents. */
2911
2912 static enum oload_classification
2913 classify_oload_match (struct badness_vector *oload_champ_bv,
2914 int nargs,
2915 int static_offset)
2916 {
2917 int ix;
2918
2919 for (ix = 1; ix <= nargs - static_offset; ix++)
2920 {
2921 if (oload_champ_bv->rank[ix] >= 100)
2922 return INCOMPATIBLE; /* Truly mismatched types. */
2923 else if (oload_champ_bv->rank[ix] >= 10)
2924 return NON_STANDARD; /* Non-standard type conversions
2925 needed. */
2926 }
2927
2928 return STANDARD; /* Only standard conversions needed. */
2929 }
2930
2931 /* C++: return 1 is NAME is a legitimate name for the destructor of
2932 type TYPE. If TYPE does not have a destructor, or if NAME is
2933 inappropriate for TYPE, an error is signaled. */
2934 int
2935 destructor_name_p (const char *name, const struct type *type)
2936 {
2937 if (name[0] == '~')
2938 {
2939 char *dname = type_name_no_tag (type);
2940 char *cp = strchr (dname, '<');
2941 unsigned int len;
2942
2943 /* Do not compare the template part for template classes. */
2944 if (cp == NULL)
2945 len = strlen (dname);
2946 else
2947 len = cp - dname;
2948 if (strlen (name + 1) != len || strncmp (dname, name + 1, len) != 0)
2949 error (_("name of destructor must equal name of class"));
2950 else
2951 return 1;
2952 }
2953 return 0;
2954 }
2955
2956 /* Given TYPE, a structure/union,
2957 return 1 if the component named NAME from the ultimate target
2958 structure/union is defined, otherwise, return 0. */
2959
2960 int
2961 check_field (struct type *type, const char *name)
2962 {
2963 int i;
2964
2965 /* The type may be a stub. */
2966 CHECK_TYPEDEF (type);
2967
2968 for (i = TYPE_NFIELDS (type) - 1; i >= TYPE_N_BASECLASSES (type); i--)
2969 {
2970 char *t_field_name = TYPE_FIELD_NAME (type, i);
2971
2972 if (t_field_name && (strcmp_iw (t_field_name, name) == 0))
2973 return 1;
2974 }
2975
2976 /* C++: If it was not found as a data field, then try to return it
2977 as a pointer to a method. */
2978
2979 for (i = TYPE_NFN_FIELDS (type) - 1; i >= 0; --i)
2980 {
2981 if (strcmp_iw (TYPE_FN_FIELDLIST_NAME (type, i), name) == 0)
2982 return 1;
2983 }
2984
2985 for (i = TYPE_N_BASECLASSES (type) - 1; i >= 0; i--)
2986 if (check_field (TYPE_BASECLASS (type, i), name))
2987 return 1;
2988
2989 return 0;
2990 }
2991
2992 /* C++: Given an aggregate type CURTYPE, and a member name NAME,
2993 return the appropriate member (or the address of the member, if
2994 WANT_ADDRESS). This function is used to resolve user expressions
2995 of the form "DOMAIN::NAME". For more details on what happens, see
2996 the comment before value_struct_elt_for_reference. */
2997
2998 struct value *
2999 value_aggregate_elt (struct type *curtype, char *name,
3000 struct type *expect_type, int want_address,
3001 enum noside noside)
3002 {
3003 switch (TYPE_CODE (curtype))
3004 {
3005 case TYPE_CODE_STRUCT:
3006 case TYPE_CODE_UNION:
3007 return value_struct_elt_for_reference (curtype, 0, curtype,
3008 name, expect_type,
3009 want_address, noside);
3010 case TYPE_CODE_NAMESPACE:
3011 return value_namespace_elt (curtype, name,
3012 want_address, noside);
3013 default:
3014 internal_error (__FILE__, __LINE__,
3015 _("non-aggregate type in value_aggregate_elt"));
3016 }
3017 }
3018
3019 /* Compares the two method/function types T1 and T2 for "equality"
3020 with respect to the the methods' parameters. If the types of the
3021 two parameter lists are the same, returns 1; 0 otherwise. This
3022 comparison may ignore any artificial parameters in T1 if
3023 SKIP_ARTIFICIAL is non-zero. This function will ALWAYS skip
3024 the first artificial parameter in T1, assumed to be a 'this' pointer.
3025
3026 The type T2 is expected to have come from make_params (in eval.c). */
3027
3028 static int
3029 compare_parameters (struct type *t1, struct type *t2, int skip_artificial)
3030 {
3031 int start = 0;
3032
3033 if (TYPE_FIELD_ARTIFICIAL (t1, 0))
3034 ++start;
3035
3036 /* If skipping artificial fields, find the first real field
3037 in T1. */
3038 if (skip_artificial)
3039 {
3040 while (start < TYPE_NFIELDS (t1)
3041 && TYPE_FIELD_ARTIFICIAL (t1, start))
3042 ++start;
3043 }
3044
3045 /* Now compare parameters */
3046
3047 /* Special case: a method taking void. T1 will contain no
3048 non-artificial fields, and T2 will contain TYPE_CODE_VOID. */
3049 if ((TYPE_NFIELDS (t1) - start) == 0 && TYPE_NFIELDS (t2) == 1
3050 && TYPE_CODE (TYPE_FIELD_TYPE (t2, 0)) == TYPE_CODE_VOID)
3051 return 1;
3052
3053 if ((TYPE_NFIELDS (t1) - start) == TYPE_NFIELDS (t2))
3054 {
3055 int i;
3056
3057 for (i = 0; i < TYPE_NFIELDS (t2); ++i)
3058 {
3059 if (rank_one_type (TYPE_FIELD_TYPE (t1, start + i),
3060 TYPE_FIELD_TYPE (t2, i))
3061 != 0)
3062 return 0;
3063 }
3064
3065 return 1;
3066 }
3067
3068 return 0;
3069 }
3070
3071 /* C++: Given an aggregate type CURTYPE, and a member name NAME,
3072 return the address of this member as a "pointer to member" type.
3073 If INTYPE is non-null, then it will be the type of the member we
3074 are looking for. This will help us resolve "pointers to member
3075 functions". This function is used to resolve user expressions of
3076 the form "DOMAIN::NAME". */
3077
3078 static struct value *
3079 value_struct_elt_for_reference (struct type *domain, int offset,
3080 struct type *curtype, char *name,
3081 struct type *intype,
3082 int want_address,
3083 enum noside noside)
3084 {
3085 struct type *t = curtype;
3086 int i;
3087 struct value *v, *result;
3088
3089 if (TYPE_CODE (t) != TYPE_CODE_STRUCT
3090 && TYPE_CODE (t) != TYPE_CODE_UNION)
3091 error (_("Internal error: non-aggregate type to value_struct_elt_for_reference"));
3092
3093 for (i = TYPE_NFIELDS (t) - 1; i >= TYPE_N_BASECLASSES (t); i--)
3094 {
3095 char *t_field_name = TYPE_FIELD_NAME (t, i);
3096
3097 if (t_field_name && strcmp (t_field_name, name) == 0)
3098 {
3099 if (field_is_static (&TYPE_FIELD (t, i)))
3100 {
3101 v = value_static_field (t, i);
3102 if (v == NULL)
3103 error (_("static field %s has been optimized out"),
3104 name);
3105 if (want_address)
3106 v = value_addr (v);
3107 return v;
3108 }
3109 if (TYPE_FIELD_PACKED (t, i))
3110 error (_("pointers to bitfield members not allowed"));
3111
3112 if (want_address)
3113 return value_from_longest
3114 (lookup_memberptr_type (TYPE_FIELD_TYPE (t, i), domain),
3115 offset + (LONGEST) (TYPE_FIELD_BITPOS (t, i) >> 3));
3116 else if (noside == EVAL_AVOID_SIDE_EFFECTS)
3117 return allocate_value (TYPE_FIELD_TYPE (t, i));
3118 else
3119 error (_("Cannot reference non-static field \"%s\""), name);
3120 }
3121 }
3122
3123 /* C++: If it was not found as a data field, then try to return it
3124 as a pointer to a method. */
3125
3126 /* Perform all necessary dereferencing. */
3127 while (intype && TYPE_CODE (intype) == TYPE_CODE_PTR)
3128 intype = TYPE_TARGET_TYPE (intype);
3129
3130 for (i = TYPE_NFN_FIELDS (t) - 1; i >= 0; --i)
3131 {
3132 char *t_field_name = TYPE_FN_FIELDLIST_NAME (t, i);
3133 char dem_opname[64];
3134
3135 if (strncmp (t_field_name, "__", 2) == 0
3136 || strncmp (t_field_name, "op", 2) == 0
3137 || strncmp (t_field_name, "type", 4) == 0)
3138 {
3139 if (cplus_demangle_opname (t_field_name,
3140 dem_opname, DMGL_ANSI))
3141 t_field_name = dem_opname;
3142 else if (cplus_demangle_opname (t_field_name,
3143 dem_opname, 0))
3144 t_field_name = dem_opname;
3145 }
3146 if (t_field_name && strcmp (t_field_name, name) == 0)
3147 {
3148 int j;
3149 int len = TYPE_FN_FIELDLIST_LENGTH (t, i);
3150 struct fn_field *f = TYPE_FN_FIELDLIST1 (t, i);
3151
3152 check_stub_method_group (t, i);
3153
3154 if (intype)
3155 {
3156 for (j = 0; j < len; ++j)
3157 {
3158 if (compare_parameters (TYPE_FN_FIELD_TYPE (f, j), intype, 0)
3159 || compare_parameters (TYPE_FN_FIELD_TYPE (f, j), intype, 1))
3160 break;
3161 }
3162
3163 if (j == len)
3164 error (_("no member function matches that type instantiation"));
3165 }
3166 else
3167 {
3168 int ii;
3169
3170 j = -1;
3171 for (ii = 0; ii < TYPE_FN_FIELDLIST_LENGTH (t, i);
3172 ++ii)
3173 {
3174 /* Skip artificial methods. This is necessary if,
3175 for example, the user wants to "print
3176 subclass::subclass" with only one user-defined
3177 constructor. There is no ambiguity in this
3178 case. */
3179 if (TYPE_FN_FIELD_ARTIFICIAL (f, ii))
3180 continue;
3181
3182 /* Desired method is ambiguous if more than one
3183 method is defined. */
3184 if (j != -1)
3185 error (_("non-unique member `%s' requires type instantiation"), name);
3186
3187 j = ii;
3188 }
3189 }
3190
3191 if (TYPE_FN_FIELD_STATIC_P (f, j))
3192 {
3193 struct symbol *s =
3194 lookup_symbol (TYPE_FN_FIELD_PHYSNAME (f, j),
3195 0, VAR_DOMAIN, 0);
3196
3197 if (s == NULL)
3198 return NULL;
3199
3200 if (want_address)
3201 return value_addr (read_var_value (s, 0));
3202 else
3203 return read_var_value (s, 0);
3204 }
3205
3206 if (TYPE_FN_FIELD_VIRTUAL_P (f, j))
3207 {
3208 if (want_address)
3209 {
3210 result = allocate_value
3211 (lookup_methodptr_type (TYPE_FN_FIELD_TYPE (f, j)));
3212 cplus_make_method_ptr (value_type (result),
3213 value_contents_writeable (result),
3214 TYPE_FN_FIELD_VOFFSET (f, j), 1);
3215 }
3216 else if (noside == EVAL_AVOID_SIDE_EFFECTS)
3217 return allocate_value (TYPE_FN_FIELD_TYPE (f, j));
3218 else
3219 error (_("Cannot reference virtual member function \"%s\""),
3220 name);
3221 }
3222 else
3223 {
3224 struct symbol *s =
3225 lookup_symbol (TYPE_FN_FIELD_PHYSNAME (f, j),
3226 0, VAR_DOMAIN, 0);
3227
3228 if (s == NULL)
3229 return NULL;
3230
3231 v = read_var_value (s, 0);
3232 if (!want_address)
3233 result = v;
3234 else
3235 {
3236 result = allocate_value (lookup_methodptr_type (TYPE_FN_FIELD_TYPE (f, j)));
3237 cplus_make_method_ptr (value_type (result),
3238 value_contents_writeable (result),
3239 value_address (v), 0);
3240 }
3241 }
3242 return result;
3243 }
3244 }
3245 for (i = TYPE_N_BASECLASSES (t) - 1; i >= 0; i--)
3246 {
3247 struct value *v;
3248 int base_offset;
3249
3250 if (BASETYPE_VIA_VIRTUAL (t, i))
3251 base_offset = 0;
3252 else
3253 base_offset = TYPE_BASECLASS_BITPOS (t, i) / 8;
3254 v = value_struct_elt_for_reference (domain,
3255 offset + base_offset,
3256 TYPE_BASECLASS (t, i),
3257 name, intype,
3258 want_address, noside);
3259 if (v)
3260 return v;
3261 }
3262
3263 /* As a last chance, pretend that CURTYPE is a namespace, and look
3264 it up that way; this (frequently) works for types nested inside
3265 classes. */
3266
3267 return value_maybe_namespace_elt (curtype, name,
3268 want_address, noside);
3269 }
3270
3271 /* C++: Return the member NAME of the namespace given by the type
3272 CURTYPE. */
3273
3274 static struct value *
3275 value_namespace_elt (const struct type *curtype,
3276 char *name, int want_address,
3277 enum noside noside)
3278 {
3279 struct value *retval = value_maybe_namespace_elt (curtype, name,
3280 want_address,
3281 noside);
3282
3283 if (retval == NULL)
3284 error (_("No symbol \"%s\" in namespace \"%s\"."),
3285 name, TYPE_TAG_NAME (curtype));
3286
3287 return retval;
3288 }
3289
3290 /* A helper function used by value_namespace_elt and
3291 value_struct_elt_for_reference. It looks up NAME inside the
3292 context CURTYPE; this works if CURTYPE is a namespace or if CURTYPE
3293 is a class and NAME refers to a type in CURTYPE itself (as opposed
3294 to, say, some base class of CURTYPE). */
3295
3296 static struct value *
3297 value_maybe_namespace_elt (const struct type *curtype,
3298 char *name, int want_address,
3299 enum noside noside)
3300 {
3301 const char *namespace_name = TYPE_TAG_NAME (curtype);
3302 struct symbol *sym;
3303 struct value *result;
3304
3305 sym = cp_lookup_symbol_namespace (namespace_name, name,
3306 get_selected_block (0), VAR_DOMAIN);
3307
3308 if (sym == NULL)
3309 {
3310 char *concatenated_name = alloca (strlen (namespace_name) + 2
3311 + strlen (name) + 1);
3312
3313 sprintf (concatenated_name, "%s::%s", namespace_name, name);
3314 sym = lookup_static_symbol_aux (concatenated_name, VAR_DOMAIN);
3315 }
3316
3317 if (sym == NULL)
3318 return NULL;
3319 else if ((noside == EVAL_AVOID_SIDE_EFFECTS)
3320 && (SYMBOL_CLASS (sym) == LOC_TYPEDEF))
3321 result = allocate_value (SYMBOL_TYPE (sym));
3322 else
3323 result = value_of_variable (sym, get_selected_block (0));
3324
3325 if (result && want_address)
3326 result = value_addr (result);
3327
3328 return result;
3329 }
3330
3331 /* Given a pointer value V, find the real (RTTI) type of the object it
3332 points to.
3333
3334 Other parameters FULL, TOP, USING_ENC as with value_rtti_type()
3335 and refer to the values computed for the object pointed to. */
3336
3337 struct type *
3338 value_rtti_target_type (struct value *v, int *full,
3339 int *top, int *using_enc)
3340 {
3341 struct value *target;
3342
3343 target = value_ind (v);
3344
3345 return value_rtti_type (target, full, top, using_enc);
3346 }
3347
3348 /* Given a value pointed to by ARGP, check its real run-time type, and
3349 if that is different from the enclosing type, create a new value
3350 using the real run-time type as the enclosing type (and of the same
3351 type as ARGP) and return it, with the embedded offset adjusted to
3352 be the correct offset to the enclosed object. RTYPE is the type,
3353 and XFULL, XTOP, and XUSING_ENC are the other parameters, computed
3354 by value_rtti_type(). If these are available, they can be supplied
3355 and a second call to value_rtti_type() is avoided. (Pass RTYPE ==
3356 NULL if they're not available. */
3357
3358 struct value *
3359 value_full_object (struct value *argp,
3360 struct type *rtype,
3361 int xfull, int xtop,
3362 int xusing_enc)
3363 {
3364 struct type *real_type;
3365 int full = 0;
3366 int top = -1;
3367 int using_enc = 0;
3368 struct value *new_val;
3369
3370 if (rtype)
3371 {
3372 real_type = rtype;
3373 full = xfull;
3374 top = xtop;
3375 using_enc = xusing_enc;
3376 }
3377 else
3378 real_type = value_rtti_type (argp, &full, &top, &using_enc);
3379
3380 /* If no RTTI data, or if object is already complete, do nothing. */
3381 if (!real_type || real_type == value_enclosing_type (argp))
3382 return argp;
3383
3384 /* If we have the full object, but for some reason the enclosing
3385 type is wrong, set it. */
3386 /* pai: FIXME -- sounds iffy */
3387 if (full)
3388 {
3389 argp = value_change_enclosing_type (argp, real_type);
3390 return argp;
3391 }
3392
3393 /* Check if object is in memory */
3394 if (VALUE_LVAL (argp) != lval_memory)
3395 {
3396 warning (_("Couldn't retrieve complete object of RTTI type %s; object may be in register(s)."),
3397 TYPE_NAME (real_type));
3398
3399 return argp;
3400 }
3401
3402 /* All other cases -- retrieve the complete object. */
3403 /* Go back by the computed top_offset from the beginning of the
3404 object, adjusting for the embedded offset of argp if that's what
3405 value_rtti_type used for its computation. */
3406 new_val = value_at_lazy (real_type, value_address (argp) - top +
3407 (using_enc ? 0 : value_embedded_offset (argp)));
3408 deprecated_set_value_type (new_val, value_type (argp));
3409 set_value_embedded_offset (new_val, (using_enc
3410 ? top + value_embedded_offset (argp)
3411 : top));
3412 return new_val;
3413 }
3414
3415
3416 /* Return the value of the local variable, if one exists.
3417 Flag COMPLAIN signals an error if the request is made in an
3418 inappropriate context. */
3419
3420 struct value *
3421 value_of_local (const char *name, int complain)
3422 {
3423 struct symbol *func, *sym;
3424 struct block *b;
3425 struct value * ret;
3426 struct frame_info *frame;
3427
3428 if (complain)
3429 frame = get_selected_frame (_("no frame selected"));
3430 else
3431 {
3432 frame = deprecated_safe_get_selected_frame ();
3433 if (frame == 0)
3434 return 0;
3435 }
3436
3437 func = get_frame_function (frame);
3438 if (!func)
3439 {
3440 if (complain)
3441 error (_("no `%s' in nameless context"), name);
3442 else
3443 return 0;
3444 }
3445
3446 b = SYMBOL_BLOCK_VALUE (func);
3447 if (dict_empty (BLOCK_DICT (b)))
3448 {
3449 if (complain)
3450 error (_("no args, no `%s'"), name);
3451 else
3452 return 0;
3453 }
3454
3455 /* Calling lookup_block_symbol is necessary to get the LOC_REGISTER
3456 symbol instead of the LOC_ARG one (if both exist). */
3457 sym = lookup_block_symbol (b, name, VAR_DOMAIN);
3458 if (sym == NULL)
3459 {
3460 if (complain)
3461 error (_("current stack frame does not contain a variable named `%s'"),
3462 name);
3463 else
3464 return NULL;
3465 }
3466
3467 ret = read_var_value (sym, frame);
3468 if (ret == 0 && complain)
3469 error (_("`%s' argument unreadable"), name);
3470 return ret;
3471 }
3472
3473 /* C++/Objective-C: return the value of the class instance variable,
3474 if one exists. Flag COMPLAIN signals an error if the request is
3475 made in an inappropriate context. */
3476
3477 struct value *
3478 value_of_this (int complain)
3479 {
3480 if (!current_language->la_name_of_this)
3481 return 0;
3482 return value_of_local (current_language->la_name_of_this, complain);
3483 }
3484
3485 /* Create a slice (sub-string, sub-array) of ARRAY, that is LENGTH
3486 elements long, starting at LOWBOUND. The result has the same lower
3487 bound as the original ARRAY. */
3488
3489 struct value *
3490 value_slice (struct value *array, int lowbound, int length)
3491 {
3492 struct type *slice_range_type, *slice_type, *range_type;
3493 LONGEST lowerbound, upperbound;
3494 struct value *slice;
3495 struct type *array_type;
3496
3497 array_type = check_typedef (value_type (array));
3498 if (TYPE_CODE (array_type) != TYPE_CODE_ARRAY
3499 && TYPE_CODE (array_type) != TYPE_CODE_STRING
3500 && TYPE_CODE (array_type) != TYPE_CODE_BITSTRING)
3501 error (_("cannot take slice of non-array"));
3502
3503 range_type = TYPE_INDEX_TYPE (array_type);
3504 if (get_discrete_bounds (range_type, &lowerbound, &upperbound) < 0)
3505 error (_("slice from bad array or bitstring"));
3506
3507 if (lowbound < lowerbound || length < 0
3508 || lowbound + length - 1 > upperbound)
3509 error (_("slice out of range"));
3510
3511 /* FIXME-type-allocation: need a way to free this type when we are
3512 done with it. */
3513 slice_range_type = create_range_type ((struct type *) NULL,
3514 TYPE_TARGET_TYPE (range_type),
3515 lowbound,
3516 lowbound + length - 1);
3517 if (TYPE_CODE (array_type) == TYPE_CODE_BITSTRING)
3518 {
3519 int i;
3520
3521 slice_type = create_set_type ((struct type *) NULL,
3522 slice_range_type);
3523 TYPE_CODE (slice_type) = TYPE_CODE_BITSTRING;
3524 slice = value_zero (slice_type, not_lval);
3525
3526 for (i = 0; i < length; i++)
3527 {
3528 int element = value_bit_index (array_type,
3529 value_contents (array),
3530 lowbound + i);
3531
3532 if (element < 0)
3533 error (_("internal error accessing bitstring"));
3534 else if (element > 0)
3535 {
3536 int j = i % TARGET_CHAR_BIT;
3537
3538 if (gdbarch_bits_big_endian (get_type_arch (array_type)))
3539 j = TARGET_CHAR_BIT - 1 - j;
3540 value_contents_raw (slice)[i / TARGET_CHAR_BIT] |= (1 << j);
3541 }
3542 }
3543 /* We should set the address, bitssize, and bitspos, so the
3544 slice can be used on the LHS, but that may require extensions
3545 to value_assign. For now, just leave as a non_lval.
3546 FIXME. */
3547 }
3548 else
3549 {
3550 struct type *element_type = TYPE_TARGET_TYPE (array_type);
3551 LONGEST offset =
3552 (lowbound - lowerbound) * TYPE_LENGTH (check_typedef (element_type));
3553
3554 slice_type = create_array_type ((struct type *) NULL,
3555 element_type,
3556 slice_range_type);
3557 TYPE_CODE (slice_type) = TYPE_CODE (array_type);
3558
3559 if (VALUE_LVAL (array) == lval_memory && value_lazy (array))
3560 slice = allocate_value_lazy (slice_type);
3561 else
3562 {
3563 slice = allocate_value (slice_type);
3564 memcpy (value_contents_writeable (slice),
3565 value_contents (array) + offset,
3566 TYPE_LENGTH (slice_type));
3567 }
3568
3569 set_value_component_location (slice, array);
3570 VALUE_FRAME_ID (slice) = VALUE_FRAME_ID (array);
3571 set_value_offset (slice, value_offset (array) + offset);
3572 }
3573 return slice;
3574 }
3575
3576 /* Create a value for a FORTRAN complex number. Currently most of the
3577 time values are coerced to COMPLEX*16 (i.e. a complex number
3578 composed of 2 doubles. This really should be a smarter routine
3579 that figures out precision inteligently as opposed to assuming
3580 doubles. FIXME: fmb */
3581
3582 struct value *
3583 value_literal_complex (struct value *arg1,
3584 struct value *arg2,
3585 struct type *type)
3586 {
3587 struct value *val;
3588 struct type *real_type = TYPE_TARGET_TYPE (type);
3589
3590 val = allocate_value (type);
3591 arg1 = value_cast (real_type, arg1);
3592 arg2 = value_cast (real_type, arg2);
3593
3594 memcpy (value_contents_raw (val),
3595 value_contents (arg1), TYPE_LENGTH (real_type));
3596 memcpy (value_contents_raw (val) + TYPE_LENGTH (real_type),
3597 value_contents (arg2), TYPE_LENGTH (real_type));
3598 return val;
3599 }
3600
3601 /* Cast a value into the appropriate complex data type. */
3602
3603 static struct value *
3604 cast_into_complex (struct type *type, struct value *val)
3605 {
3606 struct type *real_type = TYPE_TARGET_TYPE (type);
3607
3608 if (TYPE_CODE (value_type (val)) == TYPE_CODE_COMPLEX)
3609 {
3610 struct type *val_real_type = TYPE_TARGET_TYPE (value_type (val));
3611 struct value *re_val = allocate_value (val_real_type);
3612 struct value *im_val = allocate_value (val_real_type);
3613
3614 memcpy (value_contents_raw (re_val),
3615 value_contents (val), TYPE_LENGTH (val_real_type));
3616 memcpy (value_contents_raw (im_val),
3617 value_contents (val) + TYPE_LENGTH (val_real_type),
3618 TYPE_LENGTH (val_real_type));
3619
3620 return value_literal_complex (re_val, im_val, type);
3621 }
3622 else if (TYPE_CODE (value_type (val)) == TYPE_CODE_FLT
3623 || TYPE_CODE (value_type (val)) == TYPE_CODE_INT)
3624 return value_literal_complex (val,
3625 value_zero (real_type, not_lval),
3626 type);
3627 else
3628 error (_("cannot cast non-number to complex"));
3629 }
3630
3631 void
3632 _initialize_valops (void)
3633 {
3634 add_setshow_boolean_cmd ("overload-resolution", class_support,
3635 &overload_resolution, _("\
3636 Set overload resolution in evaluating C++ functions."), _("\
3637 Show overload resolution in evaluating C++ functions."),
3638 NULL, NULL,
3639 show_overload_resolution,
3640 &setlist, &showlist);
3641 overload_resolution = 1;
3642 }
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