Support overloading of 'operator->'.
[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 #include "exceptions.h"
50
51 extern int overload_debug;
52 /* Local functions. */
53
54 static int typecmp (int staticp, int varargs, int nargs,
55 struct field t1[], struct value *t2[]);
56
57 static struct value *search_struct_field (const char *, struct value *,
58 int, struct type *, int);
59
60 static struct value *search_struct_method (const char *, struct value **,
61 struct value **,
62 int, int *, struct type *);
63
64 static int find_oload_champ_namespace (struct type **, int,
65 const char *, const char *,
66 struct symbol ***,
67 struct badness_vector **,
68 const int no_adl);
69
70 static
71 int find_oload_champ_namespace_loop (struct type **, int,
72 const char *, const char *,
73 int, struct symbol ***,
74 struct badness_vector **, int *,
75 const int no_adl);
76
77 static int find_oload_champ (struct type **, int, int, int,
78 struct fn_field *, struct symbol **,
79 struct badness_vector **);
80
81 static int oload_method_static (int, struct fn_field *, int);
82
83 enum oload_classification { STANDARD, NON_STANDARD, INCOMPATIBLE };
84
85 static enum
86 oload_classification classify_oload_match (struct badness_vector *,
87 int, int);
88
89 static struct value *value_struct_elt_for_reference (struct type *,
90 int, struct type *,
91 char *,
92 struct type *,
93 int, enum noside);
94
95 static struct value *value_namespace_elt (const struct type *,
96 char *, int , enum noside);
97
98 static struct value *value_maybe_namespace_elt (const struct type *,
99 char *, int,
100 enum noside);
101
102 static CORE_ADDR allocate_space_in_inferior (int);
103
104 static struct value *cast_into_complex (struct type *, struct value *);
105
106 static struct fn_field *find_method_list (struct value **, const char *,
107 int, struct type *, int *,
108 struct type **, int *);
109
110 void _initialize_valops (void);
111
112 #if 0
113 /* Flag for whether we want to abandon failed expression evals by
114 default. */
115
116 static int auto_abandon = 0;
117 #endif
118
119 int overload_resolution = 0;
120 static void
121 show_overload_resolution (struct ui_file *file, int from_tty,
122 struct cmd_list_element *c,
123 const char *value)
124 {
125 fprintf_filtered (file, _("\
126 Overload resolution in evaluating C++ functions is %s.\n"),
127 value);
128 }
129
130 /* Find the address of function name NAME in the inferior. If OBJF_P
131 is non-NULL, *OBJF_P will be set to the OBJFILE where the function
132 is defined. */
133
134 struct value *
135 find_function_in_inferior (const char *name, struct objfile **objf_p)
136 {
137 struct symbol *sym;
138
139 sym = lookup_symbol (name, 0, VAR_DOMAIN, 0);
140 if (sym != NULL)
141 {
142 if (SYMBOL_CLASS (sym) != LOC_BLOCK)
143 {
144 error (_("\"%s\" exists in this program but is not a function."),
145 name);
146 }
147
148 if (objf_p)
149 *objf_p = SYMBOL_SYMTAB (sym)->objfile;
150
151 return value_of_variable (sym, NULL);
152 }
153 else
154 {
155 struct minimal_symbol *msymbol =
156 lookup_minimal_symbol (name, NULL, NULL);
157
158 if (msymbol != NULL)
159 {
160 struct objfile *objfile = msymbol_objfile (msymbol);
161 struct gdbarch *gdbarch = get_objfile_arch (objfile);
162
163 struct type *type;
164 CORE_ADDR maddr;
165 type = lookup_pointer_type (builtin_type (gdbarch)->builtin_char);
166 type = lookup_function_type (type);
167 type = lookup_pointer_type (type);
168 maddr = SYMBOL_VALUE_ADDRESS (msymbol);
169
170 if (objf_p)
171 *objf_p = objfile;
172
173 return value_from_pointer (type, maddr);
174 }
175 else
176 {
177 if (!target_has_execution)
178 error (_("evaluation of this expression requires the target program to be active"));
179 else
180 error (_("evaluation of this expression requires the program to have a function \"%s\"."), name);
181 }
182 }
183 }
184
185 /* Allocate NBYTES of space in the inferior using the inferior's
186 malloc and return a value that is a pointer to the allocated
187 space. */
188
189 struct value *
190 value_allocate_space_in_inferior (int len)
191 {
192 struct objfile *objf;
193 struct value *val = find_function_in_inferior ("malloc", &objf);
194 struct gdbarch *gdbarch = get_objfile_arch (objf);
195 struct value *blocklen;
196
197 blocklen = value_from_longest (builtin_type (gdbarch)->builtin_int, len);
198 val = call_function_by_hand (val, 1, &blocklen);
199 if (value_logical_not (val))
200 {
201 if (!target_has_execution)
202 error (_("No memory available to program now: you need to start the target first"));
203 else
204 error (_("No memory available to program: call to malloc failed"));
205 }
206 return val;
207 }
208
209 static CORE_ADDR
210 allocate_space_in_inferior (int len)
211 {
212 return value_as_long (value_allocate_space_in_inferior (len));
213 }
214
215 /* Cast struct value VAL to type TYPE and return as a value.
216 Both type and val must be of TYPE_CODE_STRUCT or TYPE_CODE_UNION
217 for this to work. Typedef to one of the codes is permitted.
218 Returns NULL if the cast is neither an upcast nor a downcast. */
219
220 static struct value *
221 value_cast_structs (struct type *type, struct value *v2)
222 {
223 struct type *t1;
224 struct type *t2;
225 struct value *v;
226
227 gdb_assert (type != NULL && v2 != NULL);
228
229 t1 = check_typedef (type);
230 t2 = check_typedef (value_type (v2));
231
232 /* Check preconditions. */
233 gdb_assert ((TYPE_CODE (t1) == TYPE_CODE_STRUCT
234 || TYPE_CODE (t1) == TYPE_CODE_UNION)
235 && !!"Precondition is that type is of STRUCT or UNION kind.");
236 gdb_assert ((TYPE_CODE (t2) == TYPE_CODE_STRUCT
237 || TYPE_CODE (t2) == TYPE_CODE_UNION)
238 && !!"Precondition is that value is of STRUCT or UNION kind");
239
240 if (TYPE_NAME (t1) != NULL
241 && TYPE_NAME (t2) != NULL
242 && !strcmp (TYPE_NAME (t1), TYPE_NAME (t2)))
243 return NULL;
244
245 /* Upcasting: look in the type of the source to see if it contains the
246 type of the target as a superclass. If so, we'll need to
247 offset the pointer rather than just change its type. */
248 if (TYPE_NAME (t1) != NULL)
249 {
250 v = search_struct_field (type_name_no_tag (t1),
251 v2, 0, t2, 1);
252 if (v)
253 return v;
254 }
255
256 /* Downcasting: look in the type of the target to see if it contains the
257 type of the source as a superclass. If so, we'll need to
258 offset the pointer rather than just change its type. */
259 if (TYPE_NAME (t2) != NULL)
260 {
261 /* Try downcasting using the run-time type of the value. */
262 int full, top, using_enc;
263 struct type *real_type;
264
265 real_type = value_rtti_type (v2, &full, &top, &using_enc);
266 if (real_type)
267 {
268 v = value_full_object (v2, real_type, full, top, using_enc);
269 v = value_at_lazy (real_type, value_address (v));
270
271 /* We might be trying to cast to the outermost enclosing
272 type, in which case search_struct_field won't work. */
273 if (TYPE_NAME (real_type) != NULL
274 && !strcmp (TYPE_NAME (real_type), TYPE_NAME (t1)))
275 return v;
276
277 v = search_struct_field (type_name_no_tag (t2), v, 0, real_type, 1);
278 if (v)
279 return v;
280 }
281
282 /* Try downcasting using information from the destination type
283 T2. This wouldn't work properly for classes with virtual
284 bases, but those were handled above. */
285 v = search_struct_field (type_name_no_tag (t2),
286 value_zero (t1, not_lval), 0, t1, 1);
287 if (v)
288 {
289 /* Downcasting is possible (t1 is superclass of v2). */
290 CORE_ADDR addr2 = value_address (v2);
291
292 addr2 -= value_address (v) + value_embedded_offset (v);
293 return value_at (type, addr2);
294 }
295 }
296
297 return NULL;
298 }
299
300 /* Cast one pointer or reference type to another. Both TYPE and
301 the type of ARG2 should be pointer types, or else both should be
302 reference types. Returns the new pointer or reference. */
303
304 struct value *
305 value_cast_pointers (struct type *type, struct value *arg2)
306 {
307 struct type *type1 = check_typedef (type);
308 struct type *type2 = check_typedef (value_type (arg2));
309 struct type *t1 = check_typedef (TYPE_TARGET_TYPE (type1));
310 struct type *t2 = check_typedef (TYPE_TARGET_TYPE (type2));
311
312 if (TYPE_CODE (t1) == TYPE_CODE_STRUCT
313 && TYPE_CODE (t2) == TYPE_CODE_STRUCT
314 && !value_logical_not (arg2))
315 {
316 struct value *v2;
317
318 if (TYPE_CODE (type2) == TYPE_CODE_REF)
319 v2 = coerce_ref (arg2);
320 else
321 v2 = value_ind (arg2);
322 gdb_assert (TYPE_CODE (check_typedef (value_type (v2))) == TYPE_CODE_STRUCT
323 && !!"Why did coercion fail?");
324 v2 = value_cast_structs (t1, v2);
325 /* At this point we have what we can have, un-dereference if needed. */
326 if (v2)
327 {
328 struct value *v = value_addr (v2);
329
330 deprecated_set_value_type (v, type);
331 return v;
332 }
333 }
334
335 /* No superclass found, just change the pointer type. */
336 arg2 = value_copy (arg2);
337 deprecated_set_value_type (arg2, type);
338 arg2 = value_change_enclosing_type (arg2, type);
339 set_value_pointed_to_offset (arg2, 0); /* pai: chk_val */
340 return arg2;
341 }
342
343 /* Cast value ARG2 to type TYPE and return as a value.
344 More general than a C cast: accepts any two types of the same length,
345 and if ARG2 is an lvalue it can be cast into anything at all. */
346 /* In C++, casts may change pointer or object representations. */
347
348 struct value *
349 value_cast (struct type *type, struct value *arg2)
350 {
351 enum type_code code1;
352 enum type_code code2;
353 int scalar;
354 struct type *type2;
355
356 int convert_to_boolean = 0;
357
358 if (value_type (arg2) == type)
359 return arg2;
360
361 code1 = TYPE_CODE (check_typedef (type));
362
363 /* Check if we are casting struct reference to struct reference. */
364 if (code1 == TYPE_CODE_REF)
365 {
366 /* We dereference type; then we recurse and finally
367 we generate value of the given reference. Nothing wrong with
368 that. */
369 struct type *t1 = check_typedef (type);
370 struct type *dereftype = check_typedef (TYPE_TARGET_TYPE (t1));
371 struct value *val = value_cast (dereftype, arg2);
372
373 return value_ref (val);
374 }
375
376 code2 = TYPE_CODE (check_typedef (value_type (arg2)));
377
378 if (code2 == TYPE_CODE_REF)
379 /* We deref the value and then do the cast. */
380 return value_cast (type, coerce_ref (arg2));
381
382 CHECK_TYPEDEF (type);
383 code1 = TYPE_CODE (type);
384 arg2 = coerce_ref (arg2);
385 type2 = check_typedef (value_type (arg2));
386
387 /* You can't cast to a reference type. See value_cast_pointers
388 instead. */
389 gdb_assert (code1 != TYPE_CODE_REF);
390
391 /* A cast to an undetermined-length array_type, such as
392 (TYPE [])OBJECT, is treated like a cast to (TYPE [N])OBJECT,
393 where N is sizeof(OBJECT)/sizeof(TYPE). */
394 if (code1 == TYPE_CODE_ARRAY)
395 {
396 struct type *element_type = TYPE_TARGET_TYPE (type);
397 unsigned element_length = TYPE_LENGTH (check_typedef (element_type));
398
399 if (element_length > 0 && TYPE_ARRAY_UPPER_BOUND_IS_UNDEFINED (type))
400 {
401 struct type *range_type = TYPE_INDEX_TYPE (type);
402 int val_length = TYPE_LENGTH (type2);
403 LONGEST low_bound, high_bound, new_length;
404
405 if (get_discrete_bounds (range_type, &low_bound, &high_bound) < 0)
406 low_bound = 0, high_bound = 0;
407 new_length = val_length / element_length;
408 if (val_length % element_length != 0)
409 warning (_("array element type size does not divide object size in cast"));
410 /* FIXME-type-allocation: need a way to free this type when
411 we are done with it. */
412 range_type = create_range_type ((struct type *) NULL,
413 TYPE_TARGET_TYPE (range_type),
414 low_bound,
415 new_length + low_bound - 1);
416 deprecated_set_value_type (arg2,
417 create_array_type ((struct type *) NULL,
418 element_type,
419 range_type));
420 return arg2;
421 }
422 }
423
424 if (current_language->c_style_arrays
425 && TYPE_CODE (type2) == TYPE_CODE_ARRAY
426 && !TYPE_VECTOR (type2))
427 arg2 = value_coerce_array (arg2);
428
429 if (TYPE_CODE (type2) == TYPE_CODE_FUNC)
430 arg2 = value_coerce_function (arg2);
431
432 type2 = check_typedef (value_type (arg2));
433 code2 = TYPE_CODE (type2);
434
435 if (code1 == TYPE_CODE_COMPLEX)
436 return cast_into_complex (type, arg2);
437 if (code1 == TYPE_CODE_BOOL)
438 {
439 code1 = TYPE_CODE_INT;
440 convert_to_boolean = 1;
441 }
442 if (code1 == TYPE_CODE_CHAR)
443 code1 = TYPE_CODE_INT;
444 if (code2 == TYPE_CODE_BOOL || code2 == TYPE_CODE_CHAR)
445 code2 = TYPE_CODE_INT;
446
447 scalar = (code2 == TYPE_CODE_INT || code2 == TYPE_CODE_FLT
448 || code2 == TYPE_CODE_DECFLOAT || code2 == TYPE_CODE_ENUM
449 || code2 == TYPE_CODE_RANGE);
450
451 if ((code1 == TYPE_CODE_STRUCT || code1 == TYPE_CODE_UNION)
452 && (code2 == TYPE_CODE_STRUCT || code2 == TYPE_CODE_UNION)
453 && TYPE_NAME (type) != 0)
454 {
455 struct value *v = value_cast_structs (type, arg2);
456
457 if (v)
458 return v;
459 }
460
461 if (code1 == TYPE_CODE_FLT && scalar)
462 return value_from_double (type, value_as_double (arg2));
463 else if (code1 == TYPE_CODE_DECFLOAT && scalar)
464 {
465 enum bfd_endian byte_order = gdbarch_byte_order (get_type_arch (type));
466 int dec_len = TYPE_LENGTH (type);
467 gdb_byte dec[16];
468
469 if (code2 == TYPE_CODE_FLT)
470 decimal_from_floating (arg2, dec, dec_len, byte_order);
471 else if (code2 == TYPE_CODE_DECFLOAT)
472 decimal_convert (value_contents (arg2), TYPE_LENGTH (type2),
473 byte_order, dec, dec_len, byte_order);
474 else
475 /* The only option left is an integral type. */
476 decimal_from_integral (arg2, dec, dec_len, byte_order);
477
478 return value_from_decfloat (type, dec);
479 }
480 else if ((code1 == TYPE_CODE_INT || code1 == TYPE_CODE_ENUM
481 || code1 == TYPE_CODE_RANGE)
482 && (scalar || code2 == TYPE_CODE_PTR
483 || code2 == TYPE_CODE_MEMBERPTR))
484 {
485 LONGEST longest;
486
487 /* When we cast pointers to integers, we mustn't use
488 gdbarch_pointer_to_address to find the address the pointer
489 represents, as value_as_long would. GDB should evaluate
490 expressions just as the compiler would --- and the compiler
491 sees a cast as a simple reinterpretation of the pointer's
492 bits. */
493 if (code2 == TYPE_CODE_PTR)
494 longest = extract_unsigned_integer
495 (value_contents (arg2), TYPE_LENGTH (type2),
496 gdbarch_byte_order (get_type_arch (type2)));
497 else
498 longest = value_as_long (arg2);
499 return value_from_longest (type, convert_to_boolean ?
500 (LONGEST) (longest ? 1 : 0) : longest);
501 }
502 else if (code1 == TYPE_CODE_PTR && (code2 == TYPE_CODE_INT
503 || code2 == TYPE_CODE_ENUM
504 || code2 == TYPE_CODE_RANGE))
505 {
506 /* TYPE_LENGTH (type) is the length of a pointer, but we really
507 want the length of an address! -- we are really dealing with
508 addresses (i.e., gdb representations) not pointers (i.e.,
509 target representations) here.
510
511 This allows things like "print *(int *)0x01000234" to work
512 without printing a misleading message -- which would
513 otherwise occur when dealing with a target having two byte
514 pointers and four byte addresses. */
515
516 int addr_bit = gdbarch_addr_bit (get_type_arch (type2));
517 LONGEST longest = value_as_long (arg2);
518
519 if (addr_bit < sizeof (LONGEST) * HOST_CHAR_BIT)
520 {
521 if (longest >= ((LONGEST) 1 << addr_bit)
522 || longest <= -((LONGEST) 1 << addr_bit))
523 warning (_("value truncated"));
524 }
525 return value_from_longest (type, longest);
526 }
527 else if (code1 == TYPE_CODE_METHODPTR && code2 == TYPE_CODE_INT
528 && value_as_long (arg2) == 0)
529 {
530 struct value *result = allocate_value (type);
531
532 cplus_make_method_ptr (type, value_contents_writeable (result), 0, 0);
533 return result;
534 }
535 else if (code1 == TYPE_CODE_MEMBERPTR && code2 == TYPE_CODE_INT
536 && value_as_long (arg2) == 0)
537 {
538 /* The Itanium C++ ABI represents NULL pointers to members as
539 minus one, instead of biasing the normal case. */
540 return value_from_longest (type, -1);
541 }
542 else if (code1 == TYPE_CODE_ARRAY && TYPE_VECTOR (type) && scalar)
543 {
544 /* Widen the scalar to a vector. */
545 struct type *eltype;
546 struct value *val;
547 int i, n;
548
549 eltype = check_typedef (TYPE_TARGET_TYPE (type));
550 arg2 = value_cast (eltype, arg2);
551 val = allocate_value (type);
552 n = TYPE_LENGTH (type) / TYPE_LENGTH (eltype);
553
554 for (i = 0; i < n; i++)
555 {
556 /* Duplicate the contents of arg2 into the destination vector. */
557 memcpy (value_contents_writeable (val) + (i * TYPE_LENGTH (eltype)),
558 value_contents_all (arg2), TYPE_LENGTH (eltype));
559 }
560 return val;
561 }
562 else if (TYPE_LENGTH (type) == TYPE_LENGTH (type2))
563 {
564 if (code1 == TYPE_CODE_PTR && code2 == TYPE_CODE_PTR)
565 return value_cast_pointers (type, arg2);
566
567 arg2 = value_copy (arg2);
568 deprecated_set_value_type (arg2, type);
569 arg2 = value_change_enclosing_type (arg2, type);
570 set_value_pointed_to_offset (arg2, 0); /* pai: chk_val */
571 return arg2;
572 }
573 else if (VALUE_LVAL (arg2) == lval_memory)
574 return value_at_lazy (type, value_address (arg2));
575 else if (code1 == TYPE_CODE_VOID)
576 {
577 return value_zero (type, not_lval);
578 }
579 else
580 {
581 error (_("Invalid cast."));
582 return 0;
583 }
584 }
585
586 /* The C++ reinterpret_cast operator. */
587
588 struct value *
589 value_reinterpret_cast (struct type *type, struct value *arg)
590 {
591 struct value *result;
592 struct type *real_type = check_typedef (type);
593 struct type *arg_type, *dest_type;
594 int is_ref = 0;
595 enum type_code dest_code, arg_code;
596
597 /* Do reference, function, and array conversion. */
598 arg = coerce_array (arg);
599
600 /* Attempt to preserve the type the user asked for. */
601 dest_type = type;
602
603 /* If we are casting to a reference type, transform
604 reinterpret_cast<T&>(V) to *reinterpret_cast<T*>(&V). */
605 if (TYPE_CODE (real_type) == TYPE_CODE_REF)
606 {
607 is_ref = 1;
608 arg = value_addr (arg);
609 dest_type = lookup_pointer_type (TYPE_TARGET_TYPE (dest_type));
610 real_type = lookup_pointer_type (real_type);
611 }
612
613 arg_type = value_type (arg);
614
615 dest_code = TYPE_CODE (real_type);
616 arg_code = TYPE_CODE (arg_type);
617
618 /* We can convert pointer types, or any pointer type to int, or int
619 type to pointer. */
620 if ((dest_code == TYPE_CODE_PTR && arg_code == TYPE_CODE_INT)
621 || (dest_code == TYPE_CODE_INT && arg_code == TYPE_CODE_PTR)
622 || (dest_code == TYPE_CODE_METHODPTR && arg_code == TYPE_CODE_INT)
623 || (dest_code == TYPE_CODE_INT && arg_code == TYPE_CODE_METHODPTR)
624 || (dest_code == TYPE_CODE_MEMBERPTR && arg_code == TYPE_CODE_INT)
625 || (dest_code == TYPE_CODE_INT && arg_code == TYPE_CODE_MEMBERPTR)
626 || (dest_code == arg_code
627 && (dest_code == TYPE_CODE_PTR
628 || dest_code == TYPE_CODE_METHODPTR
629 || dest_code == TYPE_CODE_MEMBERPTR)))
630 result = value_cast (dest_type, arg);
631 else
632 error (_("Invalid reinterpret_cast"));
633
634 if (is_ref)
635 result = value_cast (type, value_ref (value_ind (result)));
636
637 return result;
638 }
639
640 /* A helper for value_dynamic_cast. This implements the first of two
641 runtime checks: we iterate over all the base classes of the value's
642 class which are equal to the desired class; if only one of these
643 holds the value, then it is the answer. */
644
645 static int
646 dynamic_cast_check_1 (struct type *desired_type,
647 const bfd_byte *contents,
648 CORE_ADDR address,
649 struct type *search_type,
650 CORE_ADDR arg_addr,
651 struct type *arg_type,
652 struct value **result)
653 {
654 int i, result_count = 0;
655
656 for (i = 0; i < TYPE_N_BASECLASSES (search_type) && result_count < 2; ++i)
657 {
658 int offset = baseclass_offset (search_type, i, contents, address);
659
660 if (offset == -1)
661 error (_("virtual baseclass botch"));
662 if (class_types_same_p (desired_type, TYPE_BASECLASS (search_type, i)))
663 {
664 if (address + offset >= arg_addr
665 && address + offset < arg_addr + TYPE_LENGTH (arg_type))
666 {
667 ++result_count;
668 if (!*result)
669 *result = value_at_lazy (TYPE_BASECLASS (search_type, i),
670 address + offset);
671 }
672 }
673 else
674 result_count += dynamic_cast_check_1 (desired_type,
675 contents + offset,
676 address + offset,
677 TYPE_BASECLASS (search_type, i),
678 arg_addr,
679 arg_type,
680 result);
681 }
682
683 return result_count;
684 }
685
686 /* A helper for value_dynamic_cast. This implements the second of two
687 runtime checks: we look for a unique public sibling class of the
688 argument's declared class. */
689
690 static int
691 dynamic_cast_check_2 (struct type *desired_type,
692 const bfd_byte *contents,
693 CORE_ADDR address,
694 struct type *search_type,
695 struct value **result)
696 {
697 int i, result_count = 0;
698
699 for (i = 0; i < TYPE_N_BASECLASSES (search_type) && result_count < 2; ++i)
700 {
701 int offset;
702
703 if (! BASETYPE_VIA_PUBLIC (search_type, i))
704 continue;
705
706 offset = baseclass_offset (search_type, i, contents, address);
707 if (offset == -1)
708 error (_("virtual baseclass botch"));
709 if (class_types_same_p (desired_type, TYPE_BASECLASS (search_type, i)))
710 {
711 ++result_count;
712 if (*result == NULL)
713 *result = value_at_lazy (TYPE_BASECLASS (search_type, i),
714 address + offset);
715 }
716 else
717 result_count += dynamic_cast_check_2 (desired_type,
718 contents + offset,
719 address + offset,
720 TYPE_BASECLASS (search_type, i),
721 result);
722 }
723
724 return result_count;
725 }
726
727 /* The C++ dynamic_cast operator. */
728
729 struct value *
730 value_dynamic_cast (struct type *type, struct value *arg)
731 {
732 int full, top, using_enc;
733 struct type *resolved_type = check_typedef (type);
734 struct type *arg_type = check_typedef (value_type (arg));
735 struct type *class_type, *rtti_type;
736 struct value *result, *tem, *original_arg = arg;
737 CORE_ADDR addr;
738 int is_ref = TYPE_CODE (resolved_type) == TYPE_CODE_REF;
739
740 if (TYPE_CODE (resolved_type) != TYPE_CODE_PTR
741 && TYPE_CODE (resolved_type) != TYPE_CODE_REF)
742 error (_("Argument to dynamic_cast must be a pointer or reference type"));
743 if (TYPE_CODE (TYPE_TARGET_TYPE (resolved_type)) != TYPE_CODE_VOID
744 && TYPE_CODE (TYPE_TARGET_TYPE (resolved_type)) != TYPE_CODE_CLASS)
745 error (_("Argument to dynamic_cast must be pointer to class or `void *'"));
746
747 class_type = check_typedef (TYPE_TARGET_TYPE (resolved_type));
748 if (TYPE_CODE (resolved_type) == TYPE_CODE_PTR)
749 {
750 if (TYPE_CODE (arg_type) != TYPE_CODE_PTR
751 && ! (TYPE_CODE (arg_type) == TYPE_CODE_INT
752 && value_as_long (arg) == 0))
753 error (_("Argument to dynamic_cast does not have pointer type"));
754 if (TYPE_CODE (arg_type) == TYPE_CODE_PTR)
755 {
756 arg_type = check_typedef (TYPE_TARGET_TYPE (arg_type));
757 if (TYPE_CODE (arg_type) != TYPE_CODE_CLASS)
758 error (_("Argument to dynamic_cast does not have pointer to class type"));
759 }
760
761 /* Handle NULL pointers. */
762 if (value_as_long (arg) == 0)
763 return value_zero (type, not_lval);
764
765 arg = value_ind (arg);
766 }
767 else
768 {
769 if (TYPE_CODE (arg_type) != TYPE_CODE_CLASS)
770 error (_("Argument to dynamic_cast does not have class type"));
771 }
772
773 /* If the classes are the same, just return the argument. */
774 if (class_types_same_p (class_type, arg_type))
775 return value_cast (type, arg);
776
777 /* If the target type is a unique base class of the argument's
778 declared type, just cast it. */
779 if (is_ancestor (class_type, arg_type))
780 {
781 if (is_unique_ancestor (class_type, arg))
782 return value_cast (type, original_arg);
783 error (_("Ambiguous dynamic_cast"));
784 }
785
786 rtti_type = value_rtti_type (arg, &full, &top, &using_enc);
787 if (! rtti_type)
788 error (_("Couldn't determine value's most derived type for dynamic_cast"));
789
790 /* Compute the most derived object's address. */
791 addr = value_address (arg);
792 if (full)
793 {
794 /* Done. */
795 }
796 else if (using_enc)
797 addr += top;
798 else
799 addr += top + value_embedded_offset (arg);
800
801 /* dynamic_cast<void *> means to return a pointer to the
802 most-derived object. */
803 if (TYPE_CODE (resolved_type) == TYPE_CODE_PTR
804 && TYPE_CODE (TYPE_TARGET_TYPE (resolved_type)) == TYPE_CODE_VOID)
805 return value_at_lazy (type, addr);
806
807 tem = value_at (type, addr);
808
809 /* The first dynamic check specified in 5.2.7. */
810 if (is_public_ancestor (arg_type, TYPE_TARGET_TYPE (resolved_type)))
811 {
812 if (class_types_same_p (rtti_type, TYPE_TARGET_TYPE (resolved_type)))
813 return tem;
814 result = NULL;
815 if (dynamic_cast_check_1 (TYPE_TARGET_TYPE (resolved_type),
816 value_contents (tem), value_address (tem),
817 rtti_type, addr,
818 arg_type,
819 &result) == 1)
820 return value_cast (type,
821 is_ref ? value_ref (result) : value_addr (result));
822 }
823
824 /* The second dynamic check specified in 5.2.7. */
825 result = NULL;
826 if (is_public_ancestor (arg_type, rtti_type)
827 && dynamic_cast_check_2 (TYPE_TARGET_TYPE (resolved_type),
828 value_contents (tem), value_address (tem),
829 rtti_type, &result) == 1)
830 return value_cast (type,
831 is_ref ? value_ref (result) : value_addr (result));
832
833 if (TYPE_CODE (resolved_type) == TYPE_CODE_PTR)
834 return value_zero (type, not_lval);
835
836 error (_("dynamic_cast failed"));
837 }
838
839 /* Create a value of type TYPE that is zero, and return it. */
840
841 struct value *
842 value_zero (struct type *type, enum lval_type lv)
843 {
844 struct value *val = allocate_value (type);
845
846 VALUE_LVAL (val) = lv;
847 return val;
848 }
849
850 /* Create a value of numeric type TYPE that is one, and return it. */
851
852 struct value *
853 value_one (struct type *type, enum lval_type lv)
854 {
855 struct type *type1 = check_typedef (type);
856 struct value *val;
857
858 if (TYPE_CODE (type1) == TYPE_CODE_DECFLOAT)
859 {
860 enum bfd_endian byte_order = gdbarch_byte_order (get_type_arch (type));
861 gdb_byte v[16];
862
863 decimal_from_string (v, TYPE_LENGTH (type), byte_order, "1");
864 val = value_from_decfloat (type, v);
865 }
866 else if (TYPE_CODE (type1) == TYPE_CODE_FLT)
867 {
868 val = value_from_double (type, (DOUBLEST) 1);
869 }
870 else if (is_integral_type (type1))
871 {
872 val = value_from_longest (type, (LONGEST) 1);
873 }
874 else
875 {
876 error (_("Not a numeric type."));
877 }
878
879 VALUE_LVAL (val) = lv;
880 return val;
881 }
882
883 /* Helper function for value_at, value_at_lazy, and value_at_lazy_stack. */
884
885 static struct value *
886 get_value_at (struct type *type, CORE_ADDR addr, int lazy)
887 {
888 struct value *val;
889
890 if (TYPE_CODE (check_typedef (type)) == TYPE_CODE_VOID)
891 error (_("Attempt to dereference a generic pointer."));
892
893 if (lazy)
894 {
895 val = allocate_value_lazy (type);
896 }
897 else
898 {
899 val = allocate_value (type);
900 read_memory (addr, value_contents_all_raw (val), TYPE_LENGTH (type));
901 }
902
903 VALUE_LVAL (val) = lval_memory;
904 set_value_address (val, addr);
905
906 return val;
907 }
908
909 /* Return a value with type TYPE located at ADDR.
910
911 Call value_at only if the data needs to be fetched immediately;
912 if we can be 'lazy' and defer the fetch, perhaps indefinately, call
913 value_at_lazy instead. value_at_lazy simply records the address of
914 the data and sets the lazy-evaluation-required flag. The lazy flag
915 is tested in the value_contents macro, which is used if and when
916 the contents are actually required.
917
918 Note: value_at does *NOT* handle embedded offsets; perform such
919 adjustments before or after calling it. */
920
921 struct value *
922 value_at (struct type *type, CORE_ADDR addr)
923 {
924 return get_value_at (type, addr, 0);
925 }
926
927 /* Return a lazy value with type TYPE located at ADDR (cf. value_at). */
928
929 struct value *
930 value_at_lazy (struct type *type, CORE_ADDR addr)
931 {
932 return get_value_at (type, addr, 1);
933 }
934
935 /* Called only from the value_contents and value_contents_all()
936 macros, if the current data for a variable needs to be loaded into
937 value_contents(VAL). Fetches the data from the user's process, and
938 clears the lazy flag to indicate that the data in the buffer is
939 valid.
940
941 If the value is zero-length, we avoid calling read_memory, which
942 would abort. We mark the value as fetched anyway -- all 0 bytes of
943 it.
944
945 This function returns a value because it is used in the
946 value_contents macro as part of an expression, where a void would
947 not work. The value is ignored. */
948
949 int
950 value_fetch_lazy (struct value *val)
951 {
952 gdb_assert (value_lazy (val));
953 allocate_value_contents (val);
954 if (value_bitsize (val))
955 {
956 /* To read a lazy bitfield, read the entire enclosing value. This
957 prevents reading the same block of (possibly volatile) memory once
958 per bitfield. It would be even better to read only the containing
959 word, but we have no way to record that just specific bits of a
960 value have been fetched. */
961 struct type *type = check_typedef (value_type (val));
962 enum bfd_endian byte_order = gdbarch_byte_order (get_type_arch (type));
963 struct value *parent = value_parent (val);
964 LONGEST offset = value_offset (val);
965 LONGEST num = unpack_bits_as_long (value_type (val),
966 (value_contents_for_printing (parent)
967 + offset),
968 value_bitpos (val),
969 value_bitsize (val));
970 int length = TYPE_LENGTH (type);
971
972 if (!value_bits_valid (val,
973 TARGET_CHAR_BIT * offset + value_bitpos (val),
974 value_bitsize (val)))
975 error (_("value has been optimized out"));
976
977 store_signed_integer (value_contents_raw (val), length, byte_order, num);
978 }
979 else if (VALUE_LVAL (val) == lval_memory)
980 {
981 CORE_ADDR addr = value_address (val);
982 int length = TYPE_LENGTH (check_typedef (value_enclosing_type (val)));
983
984 if (length)
985 {
986 if (value_stack (val))
987 read_stack (addr, value_contents_all_raw (val), length);
988 else
989 read_memory (addr, value_contents_all_raw (val), length);
990 }
991 }
992 else if (VALUE_LVAL (val) == lval_register)
993 {
994 struct frame_info *frame;
995 int regnum;
996 struct type *type = check_typedef (value_type (val));
997 struct value *new_val = val, *mark = value_mark ();
998
999 /* Offsets are not supported here; lazy register values must
1000 refer to the entire register. */
1001 gdb_assert (value_offset (val) == 0);
1002
1003 while (VALUE_LVAL (new_val) == lval_register && value_lazy (new_val))
1004 {
1005 frame = frame_find_by_id (VALUE_FRAME_ID (new_val));
1006 regnum = VALUE_REGNUM (new_val);
1007
1008 gdb_assert (frame != NULL);
1009
1010 /* Convertible register routines are used for multi-register
1011 values and for interpretation in different types
1012 (e.g. float or int from a double register). Lazy
1013 register values should have the register's natural type,
1014 so they do not apply. */
1015 gdb_assert (!gdbarch_convert_register_p (get_frame_arch (frame),
1016 regnum, type));
1017
1018 new_val = get_frame_register_value (frame, regnum);
1019 }
1020
1021 /* If it's still lazy (for instance, a saved register on the
1022 stack), fetch it. */
1023 if (value_lazy (new_val))
1024 value_fetch_lazy (new_val);
1025
1026 /* If the register was not saved, mark it unavailable. */
1027 if (value_optimized_out (new_val))
1028 set_value_optimized_out (val, 1);
1029 else
1030 memcpy (value_contents_raw (val), value_contents (new_val),
1031 TYPE_LENGTH (type));
1032
1033 if (frame_debug)
1034 {
1035 struct gdbarch *gdbarch;
1036 frame = frame_find_by_id (VALUE_FRAME_ID (val));
1037 regnum = VALUE_REGNUM (val);
1038 gdbarch = get_frame_arch (frame);
1039
1040 fprintf_unfiltered (gdb_stdlog, "\
1041 { value_fetch_lazy (frame=%d,regnum=%d(%s),...) ",
1042 frame_relative_level (frame), regnum,
1043 user_reg_map_regnum_to_name (gdbarch, regnum));
1044
1045 fprintf_unfiltered (gdb_stdlog, "->");
1046 if (value_optimized_out (new_val))
1047 fprintf_unfiltered (gdb_stdlog, " optimized out");
1048 else
1049 {
1050 int i;
1051 const gdb_byte *buf = value_contents (new_val);
1052
1053 if (VALUE_LVAL (new_val) == lval_register)
1054 fprintf_unfiltered (gdb_stdlog, " register=%d",
1055 VALUE_REGNUM (new_val));
1056 else if (VALUE_LVAL (new_val) == lval_memory)
1057 fprintf_unfiltered (gdb_stdlog, " address=%s",
1058 paddress (gdbarch,
1059 value_address (new_val)));
1060 else
1061 fprintf_unfiltered (gdb_stdlog, " computed");
1062
1063 fprintf_unfiltered (gdb_stdlog, " bytes=");
1064 fprintf_unfiltered (gdb_stdlog, "[");
1065 for (i = 0; i < register_size (gdbarch, regnum); i++)
1066 fprintf_unfiltered (gdb_stdlog, "%02x", buf[i]);
1067 fprintf_unfiltered (gdb_stdlog, "]");
1068 }
1069
1070 fprintf_unfiltered (gdb_stdlog, " }\n");
1071 }
1072
1073 /* Dispose of the intermediate values. This prevents
1074 watchpoints from trying to watch the saved frame pointer. */
1075 value_free_to_mark (mark);
1076 }
1077 else if (VALUE_LVAL (val) == lval_computed)
1078 value_computed_funcs (val)->read (val);
1079 else
1080 internal_error (__FILE__, __LINE__, "Unexpected lazy value type.");
1081
1082 set_value_lazy (val, 0);
1083 return 0;
1084 }
1085
1086
1087 /* Store the contents of FROMVAL into the location of TOVAL.
1088 Return a new value with the location of TOVAL and contents of FROMVAL. */
1089
1090 struct value *
1091 value_assign (struct value *toval, struct value *fromval)
1092 {
1093 struct type *type;
1094 struct value *val;
1095 struct frame_id old_frame;
1096
1097 if (!deprecated_value_modifiable (toval))
1098 error (_("Left operand of assignment is not a modifiable lvalue."));
1099
1100 toval = coerce_ref (toval);
1101
1102 type = value_type (toval);
1103 if (VALUE_LVAL (toval) != lval_internalvar)
1104 fromval = value_cast (type, fromval);
1105 else
1106 {
1107 /* Coerce arrays and functions to pointers, except for arrays
1108 which only live in GDB's storage. */
1109 if (!value_must_coerce_to_target (fromval))
1110 fromval = coerce_array (fromval);
1111 }
1112
1113 CHECK_TYPEDEF (type);
1114
1115 /* Since modifying a register can trash the frame chain, and
1116 modifying memory can trash the frame cache, we save the old frame
1117 and then restore the new frame afterwards. */
1118 old_frame = get_frame_id (deprecated_safe_get_selected_frame ());
1119
1120 switch (VALUE_LVAL (toval))
1121 {
1122 case lval_internalvar:
1123 set_internalvar (VALUE_INTERNALVAR (toval), fromval);
1124 val = value_copy (fromval);
1125 val = value_change_enclosing_type (val,
1126 value_enclosing_type (fromval));
1127 set_value_embedded_offset (val, value_embedded_offset (fromval));
1128 set_value_pointed_to_offset (val,
1129 value_pointed_to_offset (fromval));
1130 return val;
1131
1132 case lval_internalvar_component:
1133 set_internalvar_component (VALUE_INTERNALVAR (toval),
1134 value_offset (toval),
1135 value_bitpos (toval),
1136 value_bitsize (toval),
1137 fromval);
1138 break;
1139
1140 case lval_memory:
1141 {
1142 const gdb_byte *dest_buffer;
1143 CORE_ADDR changed_addr;
1144 int changed_len;
1145 gdb_byte buffer[sizeof (LONGEST)];
1146
1147 if (value_bitsize (toval))
1148 {
1149 struct value *parent = value_parent (toval);
1150
1151 changed_addr = value_address (parent) + value_offset (toval);
1152 changed_len = (value_bitpos (toval)
1153 + value_bitsize (toval)
1154 + HOST_CHAR_BIT - 1)
1155 / HOST_CHAR_BIT;
1156
1157 /* If we can read-modify-write exactly the size of the
1158 containing type (e.g. short or int) then do so. This
1159 is safer for volatile bitfields mapped to hardware
1160 registers. */
1161 if (changed_len < TYPE_LENGTH (type)
1162 && TYPE_LENGTH (type) <= (int) sizeof (LONGEST)
1163 && ((LONGEST) changed_addr % TYPE_LENGTH (type)) == 0)
1164 changed_len = TYPE_LENGTH (type);
1165
1166 if (changed_len > (int) sizeof (LONGEST))
1167 error (_("Can't handle bitfields which don't fit in a %d bit word."),
1168 (int) sizeof (LONGEST) * HOST_CHAR_BIT);
1169
1170 read_memory (changed_addr, buffer, changed_len);
1171 modify_field (type, buffer, value_as_long (fromval),
1172 value_bitpos (toval), value_bitsize (toval));
1173 dest_buffer = buffer;
1174 }
1175 else
1176 {
1177 changed_addr = value_address (toval);
1178 changed_len = TYPE_LENGTH (type);
1179 dest_buffer = value_contents (fromval);
1180 }
1181
1182 write_memory (changed_addr, dest_buffer, changed_len);
1183 observer_notify_memory_changed (changed_addr, changed_len,
1184 dest_buffer);
1185 }
1186 break;
1187
1188 case lval_register:
1189 {
1190 struct frame_info *frame;
1191 struct gdbarch *gdbarch;
1192 int value_reg;
1193
1194 /* Figure out which frame this is in currently. */
1195 frame = frame_find_by_id (VALUE_FRAME_ID (toval));
1196 value_reg = VALUE_REGNUM (toval);
1197
1198 if (!frame)
1199 error (_("Value being assigned to is no longer active."));
1200
1201 gdbarch = get_frame_arch (frame);
1202 if (gdbarch_convert_register_p (gdbarch, VALUE_REGNUM (toval), type))
1203 {
1204 /* If TOVAL is a special machine register requiring
1205 conversion of program values to a special raw
1206 format. */
1207 gdbarch_value_to_register (gdbarch, frame,
1208 VALUE_REGNUM (toval), type,
1209 value_contents (fromval));
1210 }
1211 else
1212 {
1213 if (value_bitsize (toval))
1214 {
1215 struct value *parent = value_parent (toval);
1216 int offset = value_offset (parent) + value_offset (toval);
1217 int changed_len;
1218 gdb_byte buffer[sizeof (LONGEST)];
1219
1220 changed_len = (value_bitpos (toval)
1221 + value_bitsize (toval)
1222 + HOST_CHAR_BIT - 1)
1223 / HOST_CHAR_BIT;
1224
1225 if (changed_len > (int) sizeof (LONGEST))
1226 error (_("Can't handle bitfields which don't fit in a %d bit word."),
1227 (int) sizeof (LONGEST) * HOST_CHAR_BIT);
1228
1229 get_frame_register_bytes (frame, value_reg, offset,
1230 changed_len, buffer);
1231
1232 modify_field (type, buffer, value_as_long (fromval),
1233 value_bitpos (toval), value_bitsize (toval));
1234
1235 put_frame_register_bytes (frame, value_reg, offset,
1236 changed_len, buffer);
1237 }
1238 else
1239 {
1240 put_frame_register_bytes (frame, value_reg,
1241 value_offset (toval),
1242 TYPE_LENGTH (type),
1243 value_contents (fromval));
1244 }
1245 }
1246
1247 if (deprecated_register_changed_hook)
1248 deprecated_register_changed_hook (-1);
1249 observer_notify_target_changed (&current_target);
1250 break;
1251 }
1252
1253 case lval_computed:
1254 {
1255 struct lval_funcs *funcs = value_computed_funcs (toval);
1256
1257 funcs->write (toval, fromval);
1258 }
1259 break;
1260
1261 default:
1262 error (_("Left operand of assignment is not an lvalue."));
1263 }
1264
1265 /* Assigning to the stack pointer, frame pointer, and other
1266 (architecture and calling convention specific) registers may
1267 cause the frame cache to be out of date. Assigning to memory
1268 also can. We just do this on all assignments to registers or
1269 memory, for simplicity's sake; I doubt the slowdown matters. */
1270 switch (VALUE_LVAL (toval))
1271 {
1272 case lval_memory:
1273 case lval_register:
1274 case lval_computed:
1275
1276 reinit_frame_cache ();
1277
1278 /* Having destroyed the frame cache, restore the selected
1279 frame. */
1280
1281 /* FIXME: cagney/2002-11-02: There has to be a better way of
1282 doing this. Instead of constantly saving/restoring the
1283 frame. Why not create a get_selected_frame() function that,
1284 having saved the selected frame's ID can automatically
1285 re-find the previously selected frame automatically. */
1286
1287 {
1288 struct frame_info *fi = frame_find_by_id (old_frame);
1289
1290 if (fi != NULL)
1291 select_frame (fi);
1292 }
1293
1294 break;
1295 default:
1296 break;
1297 }
1298
1299 /* If the field does not entirely fill a LONGEST, then zero the sign
1300 bits. If the field is signed, and is negative, then sign
1301 extend. */
1302 if ((value_bitsize (toval) > 0)
1303 && (value_bitsize (toval) < 8 * (int) sizeof (LONGEST)))
1304 {
1305 LONGEST fieldval = value_as_long (fromval);
1306 LONGEST valmask = (((ULONGEST) 1) << value_bitsize (toval)) - 1;
1307
1308 fieldval &= valmask;
1309 if (!TYPE_UNSIGNED (type)
1310 && (fieldval & (valmask ^ (valmask >> 1))))
1311 fieldval |= ~valmask;
1312
1313 fromval = value_from_longest (type, fieldval);
1314 }
1315
1316 val = value_copy (toval);
1317 memcpy (value_contents_raw (val), value_contents (fromval),
1318 TYPE_LENGTH (type));
1319 deprecated_set_value_type (val, type);
1320 val = value_change_enclosing_type (val,
1321 value_enclosing_type (fromval));
1322 set_value_embedded_offset (val, value_embedded_offset (fromval));
1323 set_value_pointed_to_offset (val, value_pointed_to_offset (fromval));
1324
1325 return val;
1326 }
1327
1328 /* Extend a value VAL to COUNT repetitions of its type. */
1329
1330 struct value *
1331 value_repeat (struct value *arg1, int count)
1332 {
1333 struct value *val;
1334
1335 if (VALUE_LVAL (arg1) != lval_memory)
1336 error (_("Only values in memory can be extended with '@'."));
1337 if (count < 1)
1338 error (_("Invalid number %d of repetitions."), count);
1339
1340 val = allocate_repeat_value (value_enclosing_type (arg1), count);
1341
1342 read_memory (value_address (arg1),
1343 value_contents_all_raw (val),
1344 TYPE_LENGTH (value_enclosing_type (val)));
1345 VALUE_LVAL (val) = lval_memory;
1346 set_value_address (val, value_address (arg1));
1347
1348 return val;
1349 }
1350
1351 struct value *
1352 value_of_variable (struct symbol *var, struct block *b)
1353 {
1354 struct value *val;
1355 struct frame_info *frame;
1356
1357 if (!symbol_read_needs_frame (var))
1358 frame = NULL;
1359 else if (!b)
1360 frame = get_selected_frame (_("No frame selected."));
1361 else
1362 {
1363 frame = block_innermost_frame (b);
1364 if (!frame)
1365 {
1366 if (BLOCK_FUNCTION (b) && !block_inlined_p (b)
1367 && SYMBOL_PRINT_NAME (BLOCK_FUNCTION (b)))
1368 error (_("No frame is currently executing in block %s."),
1369 SYMBOL_PRINT_NAME (BLOCK_FUNCTION (b)));
1370 else
1371 error (_("No frame is currently executing in specified block"));
1372 }
1373 }
1374
1375 val = read_var_value (var, frame);
1376 if (!val)
1377 error (_("Address of symbol \"%s\" is unknown."), SYMBOL_PRINT_NAME (var));
1378
1379 return val;
1380 }
1381
1382 struct value *
1383 address_of_variable (struct symbol *var, struct block *b)
1384 {
1385 struct type *type = SYMBOL_TYPE (var);
1386 struct value *val;
1387
1388 /* Evaluate it first; if the result is a memory address, we're fine.
1389 Lazy evaluation pays off here. */
1390
1391 val = value_of_variable (var, b);
1392
1393 if ((VALUE_LVAL (val) == lval_memory && value_lazy (val))
1394 || TYPE_CODE (type) == TYPE_CODE_FUNC)
1395 {
1396 CORE_ADDR addr = value_address (val);
1397
1398 return value_from_pointer (lookup_pointer_type (type), addr);
1399 }
1400
1401 /* Not a memory address; check what the problem was. */
1402 switch (VALUE_LVAL (val))
1403 {
1404 case lval_register:
1405 {
1406 struct frame_info *frame;
1407 const char *regname;
1408
1409 frame = frame_find_by_id (VALUE_FRAME_ID (val));
1410 gdb_assert (frame);
1411
1412 regname = gdbarch_register_name (get_frame_arch (frame),
1413 VALUE_REGNUM (val));
1414 gdb_assert (regname && *regname);
1415
1416 error (_("Address requested for identifier "
1417 "\"%s\" which is in register $%s"),
1418 SYMBOL_PRINT_NAME (var), regname);
1419 break;
1420 }
1421
1422 default:
1423 error (_("Can't take address of \"%s\" which isn't an lvalue."),
1424 SYMBOL_PRINT_NAME (var));
1425 break;
1426 }
1427
1428 return val;
1429 }
1430
1431 /* Return one if VAL does not live in target memory, but should in order
1432 to operate on it. Otherwise return zero. */
1433
1434 int
1435 value_must_coerce_to_target (struct value *val)
1436 {
1437 struct type *valtype;
1438
1439 /* The only lval kinds which do not live in target memory. */
1440 if (VALUE_LVAL (val) != not_lval
1441 && VALUE_LVAL (val) != lval_internalvar)
1442 return 0;
1443
1444 valtype = check_typedef (value_type (val));
1445
1446 switch (TYPE_CODE (valtype))
1447 {
1448 case TYPE_CODE_ARRAY:
1449 return TYPE_VECTOR (valtype) ? 0 : 1;
1450 case TYPE_CODE_STRING:
1451 return 1;
1452 default:
1453 return 0;
1454 }
1455 }
1456
1457 /* Make sure that VAL lives in target memory if it's supposed to. For instance,
1458 strings are constructed as character arrays in GDB's storage, and this
1459 function copies them to the target. */
1460
1461 struct value *
1462 value_coerce_to_target (struct value *val)
1463 {
1464 LONGEST length;
1465 CORE_ADDR addr;
1466
1467 if (!value_must_coerce_to_target (val))
1468 return val;
1469
1470 length = TYPE_LENGTH (check_typedef (value_type (val)));
1471 addr = allocate_space_in_inferior (length);
1472 write_memory (addr, value_contents (val), length);
1473 return value_at_lazy (value_type (val), addr);
1474 }
1475
1476 /* Given a value which is an array, return a value which is a pointer
1477 to its first element, regardless of whether or not the array has a
1478 nonzero lower bound.
1479
1480 FIXME: A previous comment here indicated that this routine should
1481 be substracting the array's lower bound. It's not clear to me that
1482 this is correct. Given an array subscripting operation, it would
1483 certainly work to do the adjustment here, essentially computing:
1484
1485 (&array[0] - (lowerbound * sizeof array[0])) + (index * sizeof array[0])
1486
1487 However I believe a more appropriate and logical place to account
1488 for the lower bound is to do so in value_subscript, essentially
1489 computing:
1490
1491 (&array[0] + ((index - lowerbound) * sizeof array[0]))
1492
1493 As further evidence consider what would happen with operations
1494 other than array subscripting, where the caller would get back a
1495 value that had an address somewhere before the actual first element
1496 of the array, and the information about the lower bound would be
1497 lost because of the coercion to pointer type.
1498 */
1499
1500 struct value *
1501 value_coerce_array (struct value *arg1)
1502 {
1503 struct type *type = check_typedef (value_type (arg1));
1504
1505 /* If the user tries to do something requiring a pointer with an
1506 array that has not yet been pushed to the target, then this would
1507 be a good time to do so. */
1508 arg1 = value_coerce_to_target (arg1);
1509
1510 if (VALUE_LVAL (arg1) != lval_memory)
1511 error (_("Attempt to take address of value not located in memory."));
1512
1513 return value_from_pointer (lookup_pointer_type (TYPE_TARGET_TYPE (type)),
1514 value_address (arg1));
1515 }
1516
1517 /* Given a value which is a function, return a value which is a pointer
1518 to it. */
1519
1520 struct value *
1521 value_coerce_function (struct value *arg1)
1522 {
1523 struct value *retval;
1524
1525 if (VALUE_LVAL (arg1) != lval_memory)
1526 error (_("Attempt to take address of value not located in memory."));
1527
1528 retval = value_from_pointer (lookup_pointer_type (value_type (arg1)),
1529 value_address (arg1));
1530 return retval;
1531 }
1532
1533 /* Return a pointer value for the object for which ARG1 is the
1534 contents. */
1535
1536 struct value *
1537 value_addr (struct value *arg1)
1538 {
1539 struct value *arg2;
1540 struct type *type = check_typedef (value_type (arg1));
1541
1542 if (TYPE_CODE (type) == TYPE_CODE_REF)
1543 {
1544 /* Copy the value, but change the type from (T&) to (T*). We
1545 keep the same location information, which is efficient, and
1546 allows &(&X) to get the location containing the reference. */
1547 arg2 = value_copy (arg1);
1548 deprecated_set_value_type (arg2,
1549 lookup_pointer_type (TYPE_TARGET_TYPE (type)));
1550 return arg2;
1551 }
1552 if (TYPE_CODE (type) == TYPE_CODE_FUNC)
1553 return value_coerce_function (arg1);
1554
1555 /* If this is an array that has not yet been pushed to the target,
1556 then this would be a good time to force it to memory. */
1557 arg1 = value_coerce_to_target (arg1);
1558
1559 if (VALUE_LVAL (arg1) != lval_memory)
1560 error (_("Attempt to take address of value not located in memory."));
1561
1562 /* Get target memory address */
1563 arg2 = value_from_pointer (lookup_pointer_type (value_type (arg1)),
1564 (value_address (arg1)
1565 + value_embedded_offset (arg1)));
1566
1567 /* This may be a pointer to a base subobject; so remember the
1568 full derived object's type ... */
1569 arg2 = value_change_enclosing_type (arg2, lookup_pointer_type (value_enclosing_type (arg1)));
1570 /* ... and also the relative position of the subobject in the full
1571 object. */
1572 set_value_pointed_to_offset (arg2, value_embedded_offset (arg1));
1573 return arg2;
1574 }
1575
1576 /* Return a reference value for the object for which ARG1 is the
1577 contents. */
1578
1579 struct value *
1580 value_ref (struct value *arg1)
1581 {
1582 struct value *arg2;
1583 struct type *type = check_typedef (value_type (arg1));
1584
1585 if (TYPE_CODE (type) == TYPE_CODE_REF)
1586 return arg1;
1587
1588 arg2 = value_addr (arg1);
1589 deprecated_set_value_type (arg2, lookup_reference_type (type));
1590 return arg2;
1591 }
1592
1593 /* Given a value of a pointer type, apply the C unary * operator to
1594 it. */
1595
1596 struct value *
1597 value_ind (struct value *arg1)
1598 {
1599 struct type *base_type;
1600 struct value *arg2;
1601
1602 arg1 = coerce_array (arg1);
1603
1604 base_type = check_typedef (value_type (arg1));
1605
1606 if (TYPE_CODE (base_type) == TYPE_CODE_PTR)
1607 {
1608 struct type *enc_type;
1609
1610 /* We may be pointing to something embedded in a larger object.
1611 Get the real type of the enclosing object. */
1612 enc_type = check_typedef (value_enclosing_type (arg1));
1613 enc_type = TYPE_TARGET_TYPE (enc_type);
1614
1615 if (TYPE_CODE (check_typedef (enc_type)) == TYPE_CODE_FUNC
1616 || TYPE_CODE (check_typedef (enc_type)) == TYPE_CODE_METHOD)
1617 /* For functions, go through find_function_addr, which knows
1618 how to handle function descriptors. */
1619 arg2 = value_at_lazy (enc_type,
1620 find_function_addr (arg1, NULL));
1621 else
1622 /* Retrieve the enclosing object pointed to */
1623 arg2 = value_at_lazy (enc_type,
1624 (value_as_address (arg1)
1625 - value_pointed_to_offset (arg1)));
1626
1627 /* Re-adjust type. */
1628 deprecated_set_value_type (arg2, TYPE_TARGET_TYPE (base_type));
1629 /* Add embedding info. */
1630 arg2 = value_change_enclosing_type (arg2, enc_type);
1631 set_value_embedded_offset (arg2, value_pointed_to_offset (arg1));
1632
1633 /* We may be pointing to an object of some derived type. */
1634 arg2 = value_full_object (arg2, NULL, 0, 0, 0);
1635 return arg2;
1636 }
1637
1638 error (_("Attempt to take contents of a non-pointer value."));
1639 return 0; /* For lint -- never reached. */
1640 }
1641 \f
1642 /* Create a value for an array by allocating space in GDB, copying
1643 copying the data into that space, and then setting up an array
1644 value.
1645
1646 The array bounds are set from LOWBOUND and HIGHBOUND, and the array
1647 is populated from the values passed in ELEMVEC.
1648
1649 The element type of the array is inherited from the type of the
1650 first element, and all elements must have the same size (though we
1651 don't currently enforce any restriction on their types). */
1652
1653 struct value *
1654 value_array (int lowbound, int highbound, struct value **elemvec)
1655 {
1656 int nelem;
1657 int idx;
1658 unsigned int typelength;
1659 struct value *val;
1660 struct type *arraytype;
1661
1662 /* Validate that the bounds are reasonable and that each of the
1663 elements have the same size. */
1664
1665 nelem = highbound - lowbound + 1;
1666 if (nelem <= 0)
1667 {
1668 error (_("bad array bounds (%d, %d)"), lowbound, highbound);
1669 }
1670 typelength = TYPE_LENGTH (value_enclosing_type (elemvec[0]));
1671 for (idx = 1; idx < nelem; idx++)
1672 {
1673 if (TYPE_LENGTH (value_enclosing_type (elemvec[idx])) != typelength)
1674 {
1675 error (_("array elements must all be the same size"));
1676 }
1677 }
1678
1679 arraytype = lookup_array_range_type (value_enclosing_type (elemvec[0]),
1680 lowbound, highbound);
1681
1682 if (!current_language->c_style_arrays)
1683 {
1684 val = allocate_value (arraytype);
1685 for (idx = 0; idx < nelem; idx++)
1686 {
1687 memcpy (value_contents_all_raw (val) + (idx * typelength),
1688 value_contents_all (elemvec[idx]),
1689 typelength);
1690 }
1691 return val;
1692 }
1693
1694 /* Allocate space to store the array, and then initialize it by
1695 copying in each element. */
1696
1697 val = allocate_value (arraytype);
1698 for (idx = 0; idx < nelem; idx++)
1699 memcpy (value_contents_writeable (val) + (idx * typelength),
1700 value_contents_all (elemvec[idx]),
1701 typelength);
1702 return val;
1703 }
1704
1705 struct value *
1706 value_cstring (char *ptr, int len, struct type *char_type)
1707 {
1708 struct value *val;
1709 int lowbound = current_language->string_lower_bound;
1710 int highbound = len / TYPE_LENGTH (char_type);
1711 struct type *stringtype
1712 = lookup_array_range_type (char_type, lowbound, highbound + lowbound - 1);
1713
1714 val = allocate_value (stringtype);
1715 memcpy (value_contents_raw (val), ptr, len);
1716 return val;
1717 }
1718
1719 /* Create a value for a string constant by allocating space in the
1720 inferior, copying the data into that space, and returning the
1721 address with type TYPE_CODE_STRING. PTR points to the string
1722 constant data; LEN is number of characters.
1723
1724 Note that string types are like array of char types with a lower
1725 bound of zero and an upper bound of LEN - 1. Also note that the
1726 string may contain embedded null bytes. */
1727
1728 struct value *
1729 value_string (char *ptr, int len, struct type *char_type)
1730 {
1731 struct value *val;
1732 int lowbound = current_language->string_lower_bound;
1733 int highbound = len / TYPE_LENGTH (char_type);
1734 struct type *stringtype
1735 = lookup_string_range_type (char_type, lowbound, highbound + lowbound - 1);
1736
1737 val = allocate_value (stringtype);
1738 memcpy (value_contents_raw (val), ptr, len);
1739 return val;
1740 }
1741
1742 struct value *
1743 value_bitstring (char *ptr, int len, struct type *index_type)
1744 {
1745 struct value *val;
1746 struct type *domain_type
1747 = create_range_type (NULL, index_type, 0, len - 1);
1748 struct type *type = create_set_type (NULL, domain_type);
1749
1750 TYPE_CODE (type) = TYPE_CODE_BITSTRING;
1751 val = allocate_value (type);
1752 memcpy (value_contents_raw (val), ptr, TYPE_LENGTH (type));
1753 return val;
1754 }
1755 \f
1756 /* See if we can pass arguments in T2 to a function which takes
1757 arguments of types T1. T1 is a list of NARGS arguments, and T2 is
1758 a NULL-terminated vector. If some arguments need coercion of some
1759 sort, then the coerced values are written into T2. Return value is
1760 0 if the arguments could be matched, or the position at which they
1761 differ if not.
1762
1763 STATICP is nonzero if the T1 argument list came from a static
1764 member function. T2 will still include the ``this'' pointer, but
1765 it will be skipped.
1766
1767 For non-static member functions, we ignore the first argument,
1768 which is the type of the instance variable. This is because we
1769 want to handle calls with objects from derived classes. This is
1770 not entirely correct: we should actually check to make sure that a
1771 requested operation is type secure, shouldn't we? FIXME. */
1772
1773 static int
1774 typecmp (int staticp, int varargs, int nargs,
1775 struct field t1[], struct value *t2[])
1776 {
1777 int i;
1778
1779 if (t2 == 0)
1780 internal_error (__FILE__, __LINE__,
1781 _("typecmp: no argument list"));
1782
1783 /* Skip ``this'' argument if applicable. T2 will always include
1784 THIS. */
1785 if (staticp)
1786 t2 ++;
1787
1788 for (i = 0;
1789 (i < nargs) && TYPE_CODE (t1[i].type) != TYPE_CODE_VOID;
1790 i++)
1791 {
1792 struct type *tt1, *tt2;
1793
1794 if (!t2[i])
1795 return i + 1;
1796
1797 tt1 = check_typedef (t1[i].type);
1798 tt2 = check_typedef (value_type (t2[i]));
1799
1800 if (TYPE_CODE (tt1) == TYPE_CODE_REF
1801 /* We should be doing hairy argument matching, as below. */
1802 && (TYPE_CODE (check_typedef (TYPE_TARGET_TYPE (tt1))) == TYPE_CODE (tt2)))
1803 {
1804 if (TYPE_CODE (tt2) == TYPE_CODE_ARRAY)
1805 t2[i] = value_coerce_array (t2[i]);
1806 else
1807 t2[i] = value_ref (t2[i]);
1808 continue;
1809 }
1810
1811 /* djb - 20000715 - Until the new type structure is in the
1812 place, and we can attempt things like implicit conversions,
1813 we need to do this so you can take something like a map<const
1814 char *>, and properly access map["hello"], because the
1815 argument to [] will be a reference to a pointer to a char,
1816 and the argument will be a pointer to a char. */
1817 while (TYPE_CODE(tt1) == TYPE_CODE_REF
1818 || TYPE_CODE (tt1) == TYPE_CODE_PTR)
1819 {
1820 tt1 = check_typedef( TYPE_TARGET_TYPE(tt1) );
1821 }
1822 while (TYPE_CODE(tt2) == TYPE_CODE_ARRAY
1823 || TYPE_CODE(tt2) == TYPE_CODE_PTR
1824 || TYPE_CODE(tt2) == TYPE_CODE_REF)
1825 {
1826 tt2 = check_typedef (TYPE_TARGET_TYPE(tt2));
1827 }
1828 if (TYPE_CODE (tt1) == TYPE_CODE (tt2))
1829 continue;
1830 /* Array to pointer is a `trivial conversion' according to the
1831 ARM. */
1832
1833 /* We should be doing much hairier argument matching (see
1834 section 13.2 of the ARM), but as a quick kludge, just check
1835 for the same type code. */
1836 if (TYPE_CODE (t1[i].type) != TYPE_CODE (value_type (t2[i])))
1837 return i + 1;
1838 }
1839 if (varargs || t2[i] == NULL)
1840 return 0;
1841 return i + 1;
1842 }
1843
1844 /* Helper function used by value_struct_elt to recurse through
1845 baseclasses. Look for a field NAME in ARG1. Adjust the address of
1846 ARG1 by OFFSET bytes, and search in it assuming it has (class) type
1847 TYPE. If found, return value, else return NULL.
1848
1849 If LOOKING_FOR_BASECLASS, then instead of looking for struct
1850 fields, look for a baseclass named NAME. */
1851
1852 static struct value *
1853 search_struct_field (const char *name, struct value *arg1, int offset,
1854 struct type *type, int looking_for_baseclass)
1855 {
1856 int i;
1857 int nbases;
1858
1859 CHECK_TYPEDEF (type);
1860 nbases = TYPE_N_BASECLASSES (type);
1861
1862 if (!looking_for_baseclass)
1863 for (i = TYPE_NFIELDS (type) - 1; i >= nbases; i--)
1864 {
1865 char *t_field_name = TYPE_FIELD_NAME (type, i);
1866
1867 if (t_field_name && (strcmp_iw (t_field_name, name) == 0))
1868 {
1869 struct value *v;
1870
1871 if (field_is_static (&TYPE_FIELD (type, i)))
1872 {
1873 v = value_static_field (type, i);
1874 if (v == 0)
1875 error (_("field %s is nonexistent or has been optimized out"),
1876 name);
1877 }
1878 else
1879 {
1880 v = value_primitive_field (arg1, offset, i, type);
1881 if (v == 0)
1882 error (_("there is no field named %s"), name);
1883 }
1884 return v;
1885 }
1886
1887 if (t_field_name
1888 && (t_field_name[0] == '\0'
1889 || (TYPE_CODE (type) == TYPE_CODE_UNION
1890 && (strcmp_iw (t_field_name, "else") == 0))))
1891 {
1892 struct type *field_type = TYPE_FIELD_TYPE (type, i);
1893
1894 if (TYPE_CODE (field_type) == TYPE_CODE_UNION
1895 || TYPE_CODE (field_type) == TYPE_CODE_STRUCT)
1896 {
1897 /* Look for a match through the fields of an anonymous
1898 union, or anonymous struct. C++ provides anonymous
1899 unions.
1900
1901 In the GNU Chill (now deleted from GDB)
1902 implementation of variant record types, each
1903 <alternative field> has an (anonymous) union type,
1904 each member of the union represents a <variant
1905 alternative>. Each <variant alternative> is
1906 represented as a struct, with a member for each
1907 <variant field>. */
1908
1909 struct value *v;
1910 int new_offset = offset;
1911
1912 /* This is pretty gross. In G++, the offset in an
1913 anonymous union is relative to the beginning of the
1914 enclosing struct. In the GNU Chill (now deleted
1915 from GDB) implementation of variant records, the
1916 bitpos is zero in an anonymous union field, so we
1917 have to add the offset of the union here. */
1918 if (TYPE_CODE (field_type) == TYPE_CODE_STRUCT
1919 || (TYPE_NFIELDS (field_type) > 0
1920 && TYPE_FIELD_BITPOS (field_type, 0) == 0))
1921 new_offset += TYPE_FIELD_BITPOS (type, i) / 8;
1922
1923 v = search_struct_field (name, arg1, new_offset,
1924 field_type,
1925 looking_for_baseclass);
1926 if (v)
1927 return v;
1928 }
1929 }
1930 }
1931
1932 for (i = 0; i < nbases; i++)
1933 {
1934 struct value *v;
1935 struct type *basetype = check_typedef (TYPE_BASECLASS (type, i));
1936 /* If we are looking for baseclasses, this is what we get when
1937 we hit them. But it could happen that the base part's member
1938 name is not yet filled in. */
1939 int found_baseclass = (looking_for_baseclass
1940 && TYPE_BASECLASS_NAME (type, i) != NULL
1941 && (strcmp_iw (name,
1942 TYPE_BASECLASS_NAME (type,
1943 i)) == 0));
1944
1945 if (BASETYPE_VIA_VIRTUAL (type, i))
1946 {
1947 int boffset;
1948 struct value *v2;
1949
1950 boffset = baseclass_offset (type, i,
1951 value_contents (arg1) + offset,
1952 value_address (arg1)
1953 + value_embedded_offset (arg1)
1954 + offset);
1955 if (boffset == -1)
1956 error (_("virtual baseclass botch"));
1957
1958 /* The virtual base class pointer might have been clobbered
1959 by the user program. Make sure that it still points to a
1960 valid memory location. */
1961
1962 boffset += value_embedded_offset (arg1) + offset;
1963 if (boffset < 0
1964 || boffset >= TYPE_LENGTH (value_enclosing_type (arg1)))
1965 {
1966 CORE_ADDR base_addr;
1967
1968 v2 = allocate_value (basetype);
1969 base_addr = value_address (arg1) + boffset;
1970 if (target_read_memory (base_addr,
1971 value_contents_raw (v2),
1972 TYPE_LENGTH (basetype)) != 0)
1973 error (_("virtual baseclass botch"));
1974 VALUE_LVAL (v2) = lval_memory;
1975 set_value_address (v2, base_addr);
1976 }
1977 else
1978 {
1979 v2 = value_copy (arg1);
1980 deprecated_set_value_type (v2, basetype);
1981 set_value_embedded_offset (v2, boffset);
1982 }
1983
1984 if (found_baseclass)
1985 return v2;
1986 v = search_struct_field (name, v2, 0,
1987 TYPE_BASECLASS (type, i),
1988 looking_for_baseclass);
1989 }
1990 else if (found_baseclass)
1991 v = value_primitive_field (arg1, offset, i, type);
1992 else
1993 v = search_struct_field (name, arg1,
1994 offset + TYPE_BASECLASS_BITPOS (type,
1995 i) / 8,
1996 basetype, looking_for_baseclass);
1997 if (v)
1998 return v;
1999 }
2000 return NULL;
2001 }
2002
2003 /* Helper function used by value_struct_elt to recurse through
2004 baseclasses. Look for a field NAME in ARG1. Adjust the address of
2005 ARG1 by OFFSET bytes, and search in it assuming it has (class) type
2006 TYPE.
2007
2008 If found, return value, else if name matched and args not return
2009 (value) -1, else return NULL. */
2010
2011 static struct value *
2012 search_struct_method (const char *name, struct value **arg1p,
2013 struct value **args, int offset,
2014 int *static_memfuncp, struct type *type)
2015 {
2016 int i;
2017 struct value *v;
2018 int name_matched = 0;
2019 char dem_opname[64];
2020
2021 CHECK_TYPEDEF (type);
2022 for (i = TYPE_NFN_FIELDS (type) - 1; i >= 0; i--)
2023 {
2024 char *t_field_name = TYPE_FN_FIELDLIST_NAME (type, i);
2025
2026 /* FIXME! May need to check for ARM demangling here */
2027 if (strncmp (t_field_name, "__", 2) == 0 ||
2028 strncmp (t_field_name, "op", 2) == 0 ||
2029 strncmp (t_field_name, "type", 4) == 0)
2030 {
2031 if (cplus_demangle_opname (t_field_name, dem_opname, DMGL_ANSI))
2032 t_field_name = dem_opname;
2033 else if (cplus_demangle_opname (t_field_name, dem_opname, 0))
2034 t_field_name = dem_opname;
2035 }
2036 if (t_field_name && (strcmp_iw (t_field_name, name) == 0))
2037 {
2038 int j = TYPE_FN_FIELDLIST_LENGTH (type, i) - 1;
2039 struct fn_field *f = TYPE_FN_FIELDLIST1 (type, i);
2040
2041 name_matched = 1;
2042 check_stub_method_group (type, i);
2043 if (j > 0 && args == 0)
2044 error (_("cannot resolve overloaded method `%s': no arguments supplied"), name);
2045 else if (j == 0 && args == 0)
2046 {
2047 v = value_fn_field (arg1p, f, j, type, offset);
2048 if (v != NULL)
2049 return v;
2050 }
2051 else
2052 while (j >= 0)
2053 {
2054 if (!typecmp (TYPE_FN_FIELD_STATIC_P (f, j),
2055 TYPE_VARARGS (TYPE_FN_FIELD_TYPE (f, j)),
2056 TYPE_NFIELDS (TYPE_FN_FIELD_TYPE (f, j)),
2057 TYPE_FN_FIELD_ARGS (f, j), args))
2058 {
2059 if (TYPE_FN_FIELD_VIRTUAL_P (f, j))
2060 return value_virtual_fn_field (arg1p, f, j,
2061 type, offset);
2062 if (TYPE_FN_FIELD_STATIC_P (f, j)
2063 && static_memfuncp)
2064 *static_memfuncp = 1;
2065 v = value_fn_field (arg1p, f, j, type, offset);
2066 if (v != NULL)
2067 return v;
2068 }
2069 j--;
2070 }
2071 }
2072 }
2073
2074 for (i = TYPE_N_BASECLASSES (type) - 1; i >= 0; i--)
2075 {
2076 int base_offset;
2077
2078 if (BASETYPE_VIA_VIRTUAL (type, i))
2079 {
2080 struct type *baseclass = check_typedef (TYPE_BASECLASS (type, i));
2081 const gdb_byte *base_valaddr;
2082
2083 /* The virtual base class pointer might have been
2084 clobbered by the user program. Make sure that it
2085 still points to a valid memory location. */
2086
2087 if (offset < 0 || offset >= TYPE_LENGTH (type))
2088 {
2089 gdb_byte *tmp = alloca (TYPE_LENGTH (baseclass));
2090
2091 if (target_read_memory (value_address (*arg1p) + offset,
2092 tmp, TYPE_LENGTH (baseclass)) != 0)
2093 error (_("virtual baseclass botch"));
2094 base_valaddr = tmp;
2095 }
2096 else
2097 base_valaddr = value_contents (*arg1p) + offset;
2098
2099 base_offset = baseclass_offset (type, i, base_valaddr,
2100 value_address (*arg1p) + offset);
2101 if (base_offset == -1)
2102 error (_("virtual baseclass botch"));
2103 }
2104 else
2105 {
2106 base_offset = TYPE_BASECLASS_BITPOS (type, i) / 8;
2107 }
2108 v = search_struct_method (name, arg1p, args, base_offset + offset,
2109 static_memfuncp, TYPE_BASECLASS (type, i));
2110 if (v == (struct value *) - 1)
2111 {
2112 name_matched = 1;
2113 }
2114 else if (v)
2115 {
2116 /* FIXME-bothner: Why is this commented out? Why is it here? */
2117 /* *arg1p = arg1_tmp; */
2118 return v;
2119 }
2120 }
2121 if (name_matched)
2122 return (struct value *) - 1;
2123 else
2124 return NULL;
2125 }
2126
2127 /* Given *ARGP, a value of type (pointer to a)* structure/union,
2128 extract the component named NAME from the ultimate target
2129 structure/union and return it as a value with its appropriate type.
2130 ERR is used in the error message if *ARGP's type is wrong.
2131
2132 C++: ARGS is a list of argument types to aid in the selection of
2133 an appropriate method. Also, handle derived types.
2134
2135 STATIC_MEMFUNCP, if non-NULL, points to a caller-supplied location
2136 where the truthvalue of whether the function that was resolved was
2137 a static member function or not is stored.
2138
2139 ERR is an error message to be printed in case the field is not
2140 found. */
2141
2142 struct value *
2143 value_struct_elt (struct value **argp, struct value **args,
2144 const char *name, int *static_memfuncp, const char *err)
2145 {
2146 struct type *t;
2147 struct value *v;
2148
2149 *argp = coerce_array (*argp);
2150
2151 t = check_typedef (value_type (*argp));
2152
2153 /* Follow pointers until we get to a non-pointer. */
2154
2155 while (TYPE_CODE (t) == TYPE_CODE_PTR || TYPE_CODE (t) == TYPE_CODE_REF)
2156 {
2157 *argp = value_ind (*argp);
2158 /* Don't coerce fn pointer to fn and then back again! */
2159 if (TYPE_CODE (value_type (*argp)) != TYPE_CODE_FUNC)
2160 *argp = coerce_array (*argp);
2161 t = check_typedef (value_type (*argp));
2162 }
2163
2164 if (TYPE_CODE (t) != TYPE_CODE_STRUCT
2165 && TYPE_CODE (t) != TYPE_CODE_UNION)
2166 error (_("Attempt to extract a component of a value that is not a %s."), err);
2167
2168 /* Assume it's not, unless we see that it is. */
2169 if (static_memfuncp)
2170 *static_memfuncp = 0;
2171
2172 if (!args)
2173 {
2174 /* if there are no arguments ...do this... */
2175
2176 /* Try as a field first, because if we succeed, there is less
2177 work to be done. */
2178 v = search_struct_field (name, *argp, 0, t, 0);
2179 if (v)
2180 return v;
2181
2182 /* C++: If it was not found as a data field, then try to
2183 return it as a pointer to a method. */
2184 v = search_struct_method (name, argp, args, 0,
2185 static_memfuncp, t);
2186
2187 if (v == (struct value *) - 1)
2188 error (_("Cannot take address of method %s."), name);
2189 else if (v == 0)
2190 {
2191 if (TYPE_NFN_FIELDS (t))
2192 error (_("There is no member or method named %s."), name);
2193 else
2194 error (_("There is no member named %s."), name);
2195 }
2196 return v;
2197 }
2198
2199 v = search_struct_method (name, argp, args, 0,
2200 static_memfuncp, t);
2201
2202 if (v == (struct value *) - 1)
2203 {
2204 error (_("One of the arguments you tried to pass to %s could not be converted to what the function wants."), name);
2205 }
2206 else if (v == 0)
2207 {
2208 /* See if user tried to invoke data as function. If so, hand it
2209 back. If it's not callable (i.e., a pointer to function),
2210 gdb should give an error. */
2211 v = search_struct_field (name, *argp, 0, t, 0);
2212 /* If we found an ordinary field, then it is not a method call.
2213 So, treat it as if it were a static member function. */
2214 if (v && static_memfuncp)
2215 *static_memfuncp = 1;
2216 }
2217
2218 if (!v)
2219 throw_error (NOT_FOUND_ERROR,
2220 _("Structure has no component named %s."), name);
2221 return v;
2222 }
2223
2224 /* Search through the methods of an object (and its bases) to find a
2225 specified method. Return the pointer to the fn_field list of
2226 overloaded instances.
2227
2228 Helper function for value_find_oload_list.
2229 ARGP is a pointer to a pointer to a value (the object).
2230 METHOD is a string containing the method name.
2231 OFFSET is the offset within the value.
2232 TYPE is the assumed type of the object.
2233 NUM_FNS is the number of overloaded instances.
2234 BASETYPE is set to the actual type of the subobject where the
2235 method is found.
2236 BOFFSET is the offset of the base subobject where the method is found.
2237 */
2238
2239 static struct fn_field *
2240 find_method_list (struct value **argp, const char *method,
2241 int offset, struct type *type, int *num_fns,
2242 struct type **basetype, int *boffset)
2243 {
2244 int i;
2245 struct fn_field *f;
2246 CHECK_TYPEDEF (type);
2247
2248 *num_fns = 0;
2249
2250 /* First check in object itself. */
2251 for (i = TYPE_NFN_FIELDS (type) - 1; i >= 0; i--)
2252 {
2253 /* pai: FIXME What about operators and type conversions? */
2254 char *fn_field_name = TYPE_FN_FIELDLIST_NAME (type, i);
2255
2256 if (fn_field_name && (strcmp_iw (fn_field_name, method) == 0))
2257 {
2258 int len = TYPE_FN_FIELDLIST_LENGTH (type, i);
2259 struct fn_field *f = TYPE_FN_FIELDLIST1 (type, i);
2260
2261 *num_fns = len;
2262 *basetype = type;
2263 *boffset = offset;
2264
2265 /* Resolve any stub methods. */
2266 check_stub_method_group (type, i);
2267
2268 return f;
2269 }
2270 }
2271
2272 /* Not found in object, check in base subobjects. */
2273 for (i = TYPE_N_BASECLASSES (type) - 1; i >= 0; i--)
2274 {
2275 int base_offset;
2276
2277 if (BASETYPE_VIA_VIRTUAL (type, i))
2278 {
2279 base_offset = value_offset (*argp) + offset;
2280 base_offset = baseclass_offset (type, i,
2281 value_contents (*argp) + base_offset,
2282 value_address (*argp) + base_offset);
2283 if (base_offset == -1)
2284 error (_("virtual baseclass botch"));
2285 }
2286 else /* Non-virtual base, simply use bit position from debug
2287 info. */
2288 {
2289 base_offset = TYPE_BASECLASS_BITPOS (type, i) / 8;
2290 }
2291 f = find_method_list (argp, method, base_offset + offset,
2292 TYPE_BASECLASS (type, i), num_fns,
2293 basetype, boffset);
2294 if (f)
2295 return f;
2296 }
2297 return NULL;
2298 }
2299
2300 /* Return the list of overloaded methods of a specified name.
2301
2302 ARGP is a pointer to a pointer to a value (the object).
2303 METHOD is the method name.
2304 OFFSET is the offset within the value contents.
2305 NUM_FNS is the number of overloaded instances.
2306 BASETYPE is set to the type of the base subobject that defines the
2307 method.
2308 BOFFSET is the offset of the base subobject which defines the method.
2309 */
2310
2311 struct fn_field *
2312 value_find_oload_method_list (struct value **argp, const char *method,
2313 int offset, int *num_fns,
2314 struct type **basetype, int *boffset)
2315 {
2316 struct type *t;
2317
2318 t = check_typedef (value_type (*argp));
2319
2320 /* Code snarfed from value_struct_elt. */
2321 while (TYPE_CODE (t) == TYPE_CODE_PTR || TYPE_CODE (t) == TYPE_CODE_REF)
2322 {
2323 *argp = value_ind (*argp);
2324 /* Don't coerce fn pointer to fn and then back again! */
2325 if (TYPE_CODE (value_type (*argp)) != TYPE_CODE_FUNC)
2326 *argp = coerce_array (*argp);
2327 t = check_typedef (value_type (*argp));
2328 }
2329
2330 if (TYPE_CODE (t) != TYPE_CODE_STRUCT
2331 && TYPE_CODE (t) != TYPE_CODE_UNION)
2332 error (_("Attempt to extract a component of a value that is not a struct or union"));
2333
2334 return find_method_list (argp, method, 0, t, num_fns,
2335 basetype, boffset);
2336 }
2337
2338 /* Given an array of argument types (ARGTYPES) (which includes an
2339 entry for "this" in the case of C++ methods), the number of
2340 arguments NARGS, the NAME of a function whether it's a method or
2341 not (METHOD), and the degree of laxness (LAX) in conforming to
2342 overload resolution rules in ANSI C++, find the best function that
2343 matches on the argument types according to the overload resolution
2344 rules.
2345
2346 METHOD can be one of three values:
2347 NON_METHOD for non-member functions.
2348 METHOD: for member functions.
2349 BOTH: used for overload resolution of operators where the
2350 candidates are expected to be either member or non member
2351 functions. In this case the first argument ARGTYPES
2352 (representing 'this') is expected to be a reference to the
2353 target object, and will be dereferenced when attempting the
2354 non-member search.
2355
2356 In the case of class methods, the parameter OBJ is an object value
2357 in which to search for overloaded methods.
2358
2359 In the case of non-method functions, the parameter FSYM is a symbol
2360 corresponding to one of the overloaded functions.
2361
2362 Return value is an integer: 0 -> good match, 10 -> debugger applied
2363 non-standard coercions, 100 -> incompatible.
2364
2365 If a method is being searched for, VALP will hold the value.
2366 If a non-method is being searched for, SYMP will hold the symbol
2367 for it.
2368
2369 If a method is being searched for, and it is a static method,
2370 then STATICP will point to a non-zero value.
2371
2372 If NO_ADL argument dependent lookup is disabled. This is used to prevent
2373 ADL overload candidates when performing overload resolution for a fully
2374 qualified name.
2375
2376 Note: This function does *not* check the value of
2377 overload_resolution. Caller must check it to see whether overload
2378 resolution is permitted.
2379 */
2380
2381 int
2382 find_overload_match (struct type **arg_types, int nargs,
2383 const char *name, enum oload_search_type method,
2384 int lax, struct value **objp, struct symbol *fsym,
2385 struct value **valp, struct symbol **symp,
2386 int *staticp, const int no_adl)
2387 {
2388 struct value *obj = (objp ? *objp : NULL);
2389 /* Index of best overloaded function. */
2390 int func_oload_champ = -1;
2391 int method_oload_champ = -1;
2392
2393 /* The measure for the current best match. */
2394 struct badness_vector *method_badness = NULL;
2395 struct badness_vector *func_badness = NULL;
2396
2397 struct value *temp = obj;
2398 /* For methods, the list of overloaded methods. */
2399 struct fn_field *fns_ptr = NULL;
2400 /* For non-methods, the list of overloaded function symbols. */
2401 struct symbol **oload_syms = NULL;
2402 /* Number of overloaded instances being considered. */
2403 int num_fns = 0;
2404 struct type *basetype = NULL;
2405 int boffset;
2406
2407 struct cleanup *all_cleanups = make_cleanup (null_cleanup, NULL);
2408
2409 const char *obj_type_name = NULL;
2410 const char *func_name = NULL;
2411 enum oload_classification match_quality;
2412 enum oload_classification method_match_quality = INCOMPATIBLE;
2413 enum oload_classification func_match_quality = INCOMPATIBLE;
2414
2415 /* Get the list of overloaded methods or functions. */
2416 if (method == METHOD || method == BOTH)
2417 {
2418 gdb_assert (obj);
2419
2420 /* OBJ may be a pointer value rather than the object itself. */
2421 obj = coerce_ref (obj);
2422 while (TYPE_CODE (check_typedef (value_type (obj))) == TYPE_CODE_PTR)
2423 obj = coerce_ref (value_ind (obj));
2424 obj_type_name = TYPE_NAME (value_type (obj));
2425
2426 /* First check whether this is a data member, e.g. a pointer to
2427 a function. */
2428 if (TYPE_CODE (check_typedef (value_type (obj))) == TYPE_CODE_STRUCT)
2429 {
2430 *valp = search_struct_field (name, obj, 0,
2431 check_typedef (value_type (obj)), 0);
2432 if (*valp)
2433 {
2434 *staticp = 1;
2435 return 0;
2436 }
2437 }
2438
2439 /* Retrieve the list of methods with the name NAME. */
2440 fns_ptr = value_find_oload_method_list (&temp, name,
2441 0, &num_fns,
2442 &basetype, &boffset);
2443 /* If this is a method only search, and no methods were found
2444 the search has faild. */
2445 if (method == METHOD && (!fns_ptr || !num_fns))
2446 error (_("Couldn't find method %s%s%s"),
2447 obj_type_name,
2448 (obj_type_name && *obj_type_name) ? "::" : "",
2449 name);
2450 /* If we are dealing with stub method types, they should have
2451 been resolved by find_method_list via
2452 value_find_oload_method_list above. */
2453 if (fns_ptr)
2454 {
2455 gdb_assert (TYPE_DOMAIN_TYPE (fns_ptr[0].type) != NULL);
2456 method_oload_champ = find_oload_champ (arg_types, nargs, method,
2457 num_fns, fns_ptr,
2458 oload_syms, &method_badness);
2459
2460 method_match_quality =
2461 classify_oload_match (method_badness, nargs,
2462 oload_method_static (method, fns_ptr,
2463 method_oload_champ));
2464
2465 make_cleanup (xfree, method_badness);
2466 }
2467
2468 }
2469
2470 if (method == NON_METHOD || method == BOTH)
2471 {
2472 const char *qualified_name = NULL;
2473
2474 /* If the the overload match is being search for both
2475 as a method and non member function, the first argument
2476 must now be dereferenced. */
2477 if (method == BOTH)
2478 arg_types[0] = TYPE_TARGET_TYPE (arg_types[0]);
2479
2480 if (fsym)
2481 {
2482 qualified_name = SYMBOL_NATURAL_NAME (fsym);
2483
2484 /* If we have a function with a C++ name, try to extract just
2485 the function part. Do not try this for non-functions (e.g.
2486 function pointers). */
2487 if (qualified_name
2488 && TYPE_CODE (check_typedef (SYMBOL_TYPE (fsym))) == TYPE_CODE_FUNC)
2489 {
2490 char *temp;
2491
2492 temp = cp_func_name (qualified_name);
2493
2494 /* If cp_func_name did not remove anything, the name of the
2495 symbol did not include scope or argument types - it was
2496 probably a C-style function. */
2497 if (temp)
2498 {
2499 make_cleanup (xfree, temp);
2500 if (strcmp (temp, qualified_name) == 0)
2501 func_name = NULL;
2502 else
2503 func_name = temp;
2504 }
2505 }
2506 }
2507 else
2508 {
2509 func_name = name;
2510 qualified_name = name;
2511 }
2512
2513 /* If there was no C++ name, this must be a C-style function or
2514 not a function at all. Just return the same symbol. Do the
2515 same if cp_func_name fails for some reason. */
2516 if (func_name == NULL)
2517 {
2518 *symp = fsym;
2519 return 0;
2520 }
2521
2522 func_oload_champ = find_oload_champ_namespace (arg_types, nargs,
2523 func_name,
2524 qualified_name,
2525 &oload_syms,
2526 &func_badness,
2527 no_adl);
2528
2529 if (func_oload_champ >= 0)
2530 func_match_quality = classify_oload_match (func_badness, nargs, 0);
2531
2532 make_cleanup (xfree, oload_syms);
2533 make_cleanup (xfree, func_badness);
2534 }
2535
2536 /* Did we find a match ? */
2537 if (method_oload_champ == -1 && func_oload_champ == -1)
2538 throw_error (NOT_FOUND_ERROR,
2539 _("No symbol \"%s\" in current context."),
2540 name);
2541
2542 /* If we have found both a method match and a function
2543 match, find out which one is better, and calculate match
2544 quality. */
2545 if (method_oload_champ >= 0 && func_oload_champ >= 0)
2546 {
2547 switch (compare_badness (func_badness, method_badness))
2548 {
2549 case 0: /* Top two contenders are equally good. */
2550 /* FIXME: GDB does not support the general ambiguous
2551 case. All candidates should be collected and presented
2552 the the user. */
2553 error (_("Ambiguous overload resolution"));
2554 break;
2555 case 1: /* Incomparable top contenders. */
2556 /* This is an error incompatible candidates
2557 should not have been proposed. */
2558 error (_("Internal error: incompatible overload candidates proposed"));
2559 break;
2560 case 2: /* Function champion. */
2561 method_oload_champ = -1;
2562 match_quality = func_match_quality;
2563 break;
2564 case 3: /* Method champion. */
2565 func_oload_champ = -1;
2566 match_quality = method_match_quality;
2567 break;
2568 default:
2569 error (_("Internal error: unexpected overload comparison result"));
2570 break;
2571 }
2572 }
2573 else
2574 {
2575 /* We have either a method match or a function match. */
2576 if (method_oload_champ >= 0)
2577 match_quality = method_match_quality;
2578 else
2579 match_quality = func_match_quality;
2580 }
2581
2582 if (match_quality == INCOMPATIBLE)
2583 {
2584 if (method == METHOD)
2585 error (_("Cannot resolve method %s%s%s to any overloaded instance"),
2586 obj_type_name,
2587 (obj_type_name && *obj_type_name) ? "::" : "",
2588 name);
2589 else
2590 error (_("Cannot resolve function %s to any overloaded instance"),
2591 func_name);
2592 }
2593 else if (match_quality == NON_STANDARD)
2594 {
2595 if (method == METHOD)
2596 warning (_("Using non-standard conversion to match method %s%s%s to supplied arguments"),
2597 obj_type_name,
2598 (obj_type_name && *obj_type_name) ? "::" : "",
2599 name);
2600 else
2601 warning (_("Using non-standard conversion to match function %s to supplied arguments"),
2602 func_name);
2603 }
2604
2605 if (staticp != NULL)
2606 *staticp = oload_method_static (method, fns_ptr, method_oload_champ);
2607
2608 if (method_oload_champ >= 0)
2609 {
2610 if (TYPE_FN_FIELD_VIRTUAL_P (fns_ptr, method_oload_champ))
2611 *valp = value_virtual_fn_field (&temp, fns_ptr, method_oload_champ,
2612 basetype, boffset);
2613 else
2614 *valp = value_fn_field (&temp, fns_ptr, method_oload_champ,
2615 basetype, boffset);
2616 }
2617 else
2618 *symp = oload_syms[func_oload_champ];
2619
2620 if (objp)
2621 {
2622 struct type *temp_type = check_typedef (value_type (temp));
2623 struct type *obj_type = check_typedef (value_type (*objp));
2624
2625 if (TYPE_CODE (temp_type) != TYPE_CODE_PTR
2626 && (TYPE_CODE (obj_type) == TYPE_CODE_PTR
2627 || TYPE_CODE (obj_type) == TYPE_CODE_REF))
2628 {
2629 temp = value_addr (temp);
2630 }
2631 *objp = temp;
2632 }
2633
2634 do_cleanups (all_cleanups);
2635
2636 switch (match_quality)
2637 {
2638 case INCOMPATIBLE:
2639 return 100;
2640 case NON_STANDARD:
2641 return 10;
2642 default: /* STANDARD */
2643 return 0;
2644 }
2645 }
2646
2647 /* Find the best overload match, searching for FUNC_NAME in namespaces
2648 contained in QUALIFIED_NAME until it either finds a good match or
2649 runs out of namespaces. It stores the overloaded functions in
2650 *OLOAD_SYMS, and the badness vector in *OLOAD_CHAMP_BV. The
2651 calling function is responsible for freeing *OLOAD_SYMS and
2652 *OLOAD_CHAMP_BV. If NO_ADL, argument dependent lookup is not
2653 performned. */
2654
2655 static int
2656 find_oload_champ_namespace (struct type **arg_types, int nargs,
2657 const char *func_name,
2658 const char *qualified_name,
2659 struct symbol ***oload_syms,
2660 struct badness_vector **oload_champ_bv,
2661 const int no_adl)
2662 {
2663 int oload_champ;
2664
2665 find_oload_champ_namespace_loop (arg_types, nargs,
2666 func_name,
2667 qualified_name, 0,
2668 oload_syms, oload_champ_bv,
2669 &oload_champ,
2670 no_adl);
2671
2672 return oload_champ;
2673 }
2674
2675 /* Helper function for find_oload_champ_namespace; NAMESPACE_LEN is
2676 how deep we've looked for namespaces, and the champ is stored in
2677 OLOAD_CHAMP. The return value is 1 if the champ is a good one, 0
2678 if it isn't. Other arguments are the same as in
2679 find_oload_champ_namespace
2680
2681 It is the caller's responsibility to free *OLOAD_SYMS and
2682 *OLOAD_CHAMP_BV. */
2683
2684 static int
2685 find_oload_champ_namespace_loop (struct type **arg_types, int nargs,
2686 const char *func_name,
2687 const char *qualified_name,
2688 int namespace_len,
2689 struct symbol ***oload_syms,
2690 struct badness_vector **oload_champ_bv,
2691 int *oload_champ,
2692 const int no_adl)
2693 {
2694 int next_namespace_len = namespace_len;
2695 int searched_deeper = 0;
2696 int num_fns = 0;
2697 struct cleanup *old_cleanups;
2698 int new_oload_champ;
2699 struct symbol **new_oload_syms;
2700 struct badness_vector *new_oload_champ_bv;
2701 char *new_namespace;
2702
2703 if (next_namespace_len != 0)
2704 {
2705 gdb_assert (qualified_name[next_namespace_len] == ':');
2706 next_namespace_len += 2;
2707 }
2708 next_namespace_len +=
2709 cp_find_first_component (qualified_name + next_namespace_len);
2710
2711 /* Initialize these to values that can safely be xfree'd. */
2712 *oload_syms = NULL;
2713 *oload_champ_bv = NULL;
2714
2715 /* First, see if we have a deeper namespace we can search in.
2716 If we get a good match there, use it. */
2717
2718 if (qualified_name[next_namespace_len] == ':')
2719 {
2720 searched_deeper = 1;
2721
2722 if (find_oload_champ_namespace_loop (arg_types, nargs,
2723 func_name, qualified_name,
2724 next_namespace_len,
2725 oload_syms, oload_champ_bv,
2726 oload_champ, no_adl))
2727 {
2728 return 1;
2729 }
2730 };
2731
2732 /* If we reach here, either we're in the deepest namespace or we
2733 didn't find a good match in a deeper namespace. But, in the
2734 latter case, we still have a bad match in a deeper namespace;
2735 note that we might not find any match at all in the current
2736 namespace. (There's always a match in the deepest namespace,
2737 because this overload mechanism only gets called if there's a
2738 function symbol to start off with.) */
2739
2740 old_cleanups = make_cleanup (xfree, *oload_syms);
2741 make_cleanup (xfree, *oload_champ_bv);
2742 new_namespace = alloca (namespace_len + 1);
2743 strncpy (new_namespace, qualified_name, namespace_len);
2744 new_namespace[namespace_len] = '\0';
2745 new_oload_syms = make_symbol_overload_list (func_name,
2746 new_namespace);
2747
2748 /* If we have reached the deepest level perform argument
2749 determined lookup. */
2750 if (!searched_deeper && !no_adl)
2751 make_symbol_overload_list_adl (arg_types, nargs, func_name);
2752
2753 while (new_oload_syms[num_fns])
2754 ++num_fns;
2755
2756 new_oload_champ = find_oload_champ (arg_types, nargs, 0, num_fns,
2757 NULL, new_oload_syms,
2758 &new_oload_champ_bv);
2759
2760 /* Case 1: We found a good match. Free earlier matches (if any),
2761 and return it. Case 2: We didn't find a good match, but we're
2762 not the deepest function. Then go with the bad match that the
2763 deeper function found. Case 3: We found a bad match, and we're
2764 the deepest function. Then return what we found, even though
2765 it's a bad match. */
2766
2767 if (new_oload_champ != -1
2768 && classify_oload_match (new_oload_champ_bv, nargs, 0) == STANDARD)
2769 {
2770 *oload_syms = new_oload_syms;
2771 *oload_champ = new_oload_champ;
2772 *oload_champ_bv = new_oload_champ_bv;
2773 do_cleanups (old_cleanups);
2774 return 1;
2775 }
2776 else if (searched_deeper)
2777 {
2778 xfree (new_oload_syms);
2779 xfree (new_oload_champ_bv);
2780 discard_cleanups (old_cleanups);
2781 return 0;
2782 }
2783 else
2784 {
2785 *oload_syms = new_oload_syms;
2786 *oload_champ = new_oload_champ;
2787 *oload_champ_bv = new_oload_champ_bv;
2788 do_cleanups (old_cleanups);
2789 return 0;
2790 }
2791 }
2792
2793 /* Look for a function to take NARGS args of types ARG_TYPES. Find
2794 the best match from among the overloaded methods or functions
2795 (depending on METHOD) given by FNS_PTR or OLOAD_SYMS, respectively.
2796 The number of methods/functions in the list is given by NUM_FNS.
2797 Return the index of the best match; store an indication of the
2798 quality of the match in OLOAD_CHAMP_BV.
2799
2800 It is the caller's responsibility to free *OLOAD_CHAMP_BV. */
2801
2802 static int
2803 find_oload_champ (struct type **arg_types, int nargs, int method,
2804 int num_fns, struct fn_field *fns_ptr,
2805 struct symbol **oload_syms,
2806 struct badness_vector **oload_champ_bv)
2807 {
2808 int ix;
2809 /* A measure of how good an overloaded instance is. */
2810 struct badness_vector *bv;
2811 /* Index of best overloaded function. */
2812 int oload_champ = -1;
2813 /* Current ambiguity state for overload resolution. */
2814 int oload_ambiguous = 0;
2815 /* 0 => no ambiguity, 1 => two good funcs, 2 => incomparable funcs. */
2816
2817 *oload_champ_bv = NULL;
2818
2819 /* Consider each candidate in turn. */
2820 for (ix = 0; ix < num_fns; ix++)
2821 {
2822 int jj;
2823 int static_offset = oload_method_static (method, fns_ptr, ix);
2824 int nparms;
2825 struct type **parm_types;
2826
2827 if (method)
2828 {
2829 nparms = TYPE_NFIELDS (TYPE_FN_FIELD_TYPE (fns_ptr, ix));
2830 }
2831 else
2832 {
2833 /* If it's not a method, this is the proper place. */
2834 nparms = TYPE_NFIELDS (SYMBOL_TYPE (oload_syms[ix]));
2835 }
2836
2837 /* Prepare array of parameter types. */
2838 parm_types = (struct type **)
2839 xmalloc (nparms * (sizeof (struct type *)));
2840 for (jj = 0; jj < nparms; jj++)
2841 parm_types[jj] = (method
2842 ? (TYPE_FN_FIELD_ARGS (fns_ptr, ix)[jj].type)
2843 : TYPE_FIELD_TYPE (SYMBOL_TYPE (oload_syms[ix]),
2844 jj));
2845
2846 /* Compare parameter types to supplied argument types. Skip
2847 THIS for static methods. */
2848 bv = rank_function (parm_types, nparms,
2849 arg_types + static_offset,
2850 nargs - static_offset);
2851
2852 if (!*oload_champ_bv)
2853 {
2854 *oload_champ_bv = bv;
2855 oload_champ = 0;
2856 }
2857 else /* See whether current candidate is better or worse than
2858 previous best. */
2859 switch (compare_badness (bv, *oload_champ_bv))
2860 {
2861 case 0: /* Top two contenders are equally good. */
2862 oload_ambiguous = 1;
2863 break;
2864 case 1: /* Incomparable top contenders. */
2865 oload_ambiguous = 2;
2866 break;
2867 case 2: /* New champion, record details. */
2868 *oload_champ_bv = bv;
2869 oload_ambiguous = 0;
2870 oload_champ = ix;
2871 break;
2872 case 3:
2873 default:
2874 break;
2875 }
2876 xfree (parm_types);
2877 if (overload_debug)
2878 {
2879 if (method)
2880 fprintf_filtered (gdb_stderr,
2881 "Overloaded method instance %s, # of parms %d\n",
2882 fns_ptr[ix].physname, nparms);
2883 else
2884 fprintf_filtered (gdb_stderr,
2885 "Overloaded function instance %s # of parms %d\n",
2886 SYMBOL_DEMANGLED_NAME (oload_syms[ix]),
2887 nparms);
2888 for (jj = 0; jj < nargs - static_offset; jj++)
2889 fprintf_filtered (gdb_stderr,
2890 "...Badness @ %d : %d\n",
2891 jj, bv->rank[jj]);
2892 fprintf_filtered (gdb_stderr,
2893 "Overload resolution champion is %d, ambiguous? %d\n",
2894 oload_champ, oload_ambiguous);
2895 }
2896 }
2897
2898 return oload_champ;
2899 }
2900
2901 /* Return 1 if we're looking at a static method, 0 if we're looking at
2902 a non-static method or a function that isn't a method. */
2903
2904 static int
2905 oload_method_static (int method, struct fn_field *fns_ptr, int index)
2906 {
2907 if (method && fns_ptr && index >= 0
2908 && TYPE_FN_FIELD_STATIC_P (fns_ptr, index))
2909 return 1;
2910 else
2911 return 0;
2912 }
2913
2914 /* Check how good an overload match OLOAD_CHAMP_BV represents. */
2915
2916 static enum oload_classification
2917 classify_oload_match (struct badness_vector *oload_champ_bv,
2918 int nargs,
2919 int static_offset)
2920 {
2921 int ix;
2922
2923 for (ix = 1; ix <= nargs - static_offset; ix++)
2924 {
2925 if (oload_champ_bv->rank[ix] >= 100)
2926 return INCOMPATIBLE; /* Truly mismatched types. */
2927 else if (oload_champ_bv->rank[ix] >= 10)
2928 return NON_STANDARD; /* Non-standard type conversions
2929 needed. */
2930 }
2931
2932 return STANDARD; /* Only standard conversions needed. */
2933 }
2934
2935 /* C++: return 1 is NAME is a legitimate name for the destructor of
2936 type TYPE. If TYPE does not have a destructor, or if NAME is
2937 inappropriate for TYPE, an error is signaled. */
2938 int
2939 destructor_name_p (const char *name, const struct type *type)
2940 {
2941 if (name[0] == '~')
2942 {
2943 char *dname = type_name_no_tag (type);
2944 char *cp = strchr (dname, '<');
2945 unsigned int len;
2946
2947 /* Do not compare the template part for template classes. */
2948 if (cp == NULL)
2949 len = strlen (dname);
2950 else
2951 len = cp - dname;
2952 if (strlen (name + 1) != len || strncmp (dname, name + 1, len) != 0)
2953 error (_("name of destructor must equal name of class"));
2954 else
2955 return 1;
2956 }
2957 return 0;
2958 }
2959
2960 /* Given TYPE, a structure/union,
2961 return 1 if the component named NAME from the ultimate target
2962 structure/union is defined, otherwise, return 0. */
2963
2964 int
2965 check_field (struct type *type, const char *name)
2966 {
2967 int i;
2968
2969 /* The type may be a stub. */
2970 CHECK_TYPEDEF (type);
2971
2972 for (i = TYPE_NFIELDS (type) - 1; i >= TYPE_N_BASECLASSES (type); i--)
2973 {
2974 char *t_field_name = TYPE_FIELD_NAME (type, i);
2975
2976 if (t_field_name && (strcmp_iw (t_field_name, name) == 0))
2977 return 1;
2978 }
2979
2980 /* C++: If it was not found as a data field, then try to return it
2981 as a pointer to a method. */
2982
2983 for (i = TYPE_NFN_FIELDS (type) - 1; i >= 0; --i)
2984 {
2985 if (strcmp_iw (TYPE_FN_FIELDLIST_NAME (type, i), name) == 0)
2986 return 1;
2987 }
2988
2989 for (i = TYPE_N_BASECLASSES (type) - 1; i >= 0; i--)
2990 if (check_field (TYPE_BASECLASS (type, i), name))
2991 return 1;
2992
2993 return 0;
2994 }
2995
2996 /* C++: Given an aggregate type CURTYPE, and a member name NAME,
2997 return the appropriate member (or the address of the member, if
2998 WANT_ADDRESS). This function is used to resolve user expressions
2999 of the form "DOMAIN::NAME". For more details on what happens, see
3000 the comment before value_struct_elt_for_reference. */
3001
3002 struct value *
3003 value_aggregate_elt (struct type *curtype, char *name,
3004 struct type *expect_type, int want_address,
3005 enum noside noside)
3006 {
3007 switch (TYPE_CODE (curtype))
3008 {
3009 case TYPE_CODE_STRUCT:
3010 case TYPE_CODE_UNION:
3011 return value_struct_elt_for_reference (curtype, 0, curtype,
3012 name, expect_type,
3013 want_address, noside);
3014 case TYPE_CODE_NAMESPACE:
3015 return value_namespace_elt (curtype, name,
3016 want_address, noside);
3017 default:
3018 internal_error (__FILE__, __LINE__,
3019 _("non-aggregate type in value_aggregate_elt"));
3020 }
3021 }
3022
3023 /* Compares the two method/function types T1 and T2 for "equality"
3024 with respect to the the methods' parameters. If the types of the
3025 two parameter lists are the same, returns 1; 0 otherwise. This
3026 comparison may ignore any artificial parameters in T1 if
3027 SKIP_ARTIFICIAL is non-zero. This function will ALWAYS skip
3028 the first artificial parameter in T1, assumed to be a 'this' pointer.
3029
3030 The type T2 is expected to have come from make_params (in eval.c). */
3031
3032 static int
3033 compare_parameters (struct type *t1, struct type *t2, int skip_artificial)
3034 {
3035 int start = 0;
3036
3037 if (TYPE_FIELD_ARTIFICIAL (t1, 0))
3038 ++start;
3039
3040 /* If skipping artificial fields, find the first real field
3041 in T1. */
3042 if (skip_artificial)
3043 {
3044 while (start < TYPE_NFIELDS (t1)
3045 && TYPE_FIELD_ARTIFICIAL (t1, start))
3046 ++start;
3047 }
3048
3049 /* Now compare parameters */
3050
3051 /* Special case: a method taking void. T1 will contain no
3052 non-artificial fields, and T2 will contain TYPE_CODE_VOID. */
3053 if ((TYPE_NFIELDS (t1) - start) == 0 && TYPE_NFIELDS (t2) == 1
3054 && TYPE_CODE (TYPE_FIELD_TYPE (t2, 0)) == TYPE_CODE_VOID)
3055 return 1;
3056
3057 if ((TYPE_NFIELDS (t1) - start) == TYPE_NFIELDS (t2))
3058 {
3059 int i;
3060
3061 for (i = 0; i < TYPE_NFIELDS (t2); ++i)
3062 {
3063 if (rank_one_type (TYPE_FIELD_TYPE (t1, start + i),
3064 TYPE_FIELD_TYPE (t2, i))
3065 != 0)
3066 return 0;
3067 }
3068
3069 return 1;
3070 }
3071
3072 return 0;
3073 }
3074
3075 /* C++: Given an aggregate type CURTYPE, and a member name NAME,
3076 return the address of this member as a "pointer to member" type.
3077 If INTYPE is non-null, then it will be the type of the member we
3078 are looking for. This will help us resolve "pointers to member
3079 functions". This function is used to resolve user expressions of
3080 the form "DOMAIN::NAME". */
3081
3082 static struct value *
3083 value_struct_elt_for_reference (struct type *domain, int offset,
3084 struct type *curtype, char *name,
3085 struct type *intype,
3086 int want_address,
3087 enum noside noside)
3088 {
3089 struct type *t = curtype;
3090 int i;
3091 struct value *v, *result;
3092
3093 if (TYPE_CODE (t) != TYPE_CODE_STRUCT
3094 && TYPE_CODE (t) != TYPE_CODE_UNION)
3095 error (_("Internal error: non-aggregate type to value_struct_elt_for_reference"));
3096
3097 for (i = TYPE_NFIELDS (t) - 1; i >= TYPE_N_BASECLASSES (t); i--)
3098 {
3099 char *t_field_name = TYPE_FIELD_NAME (t, i);
3100
3101 if (t_field_name && strcmp (t_field_name, name) == 0)
3102 {
3103 if (field_is_static (&TYPE_FIELD (t, i)))
3104 {
3105 v = value_static_field (t, i);
3106 if (v == NULL)
3107 error (_("static field %s has been optimized out"),
3108 name);
3109 if (want_address)
3110 v = value_addr (v);
3111 return v;
3112 }
3113 if (TYPE_FIELD_PACKED (t, i))
3114 error (_("pointers to bitfield members not allowed"));
3115
3116 if (want_address)
3117 return value_from_longest
3118 (lookup_memberptr_type (TYPE_FIELD_TYPE (t, i), domain),
3119 offset + (LONGEST) (TYPE_FIELD_BITPOS (t, i) >> 3));
3120 else if (noside == EVAL_AVOID_SIDE_EFFECTS)
3121 return allocate_value (TYPE_FIELD_TYPE (t, i));
3122 else
3123 error (_("Cannot reference non-static field \"%s\""), name);
3124 }
3125 }
3126
3127 /* C++: If it was not found as a data field, then try to return it
3128 as a pointer to a method. */
3129
3130 /* Perform all necessary dereferencing. */
3131 while (intype && TYPE_CODE (intype) == TYPE_CODE_PTR)
3132 intype = TYPE_TARGET_TYPE (intype);
3133
3134 for (i = TYPE_NFN_FIELDS (t) - 1; i >= 0; --i)
3135 {
3136 char *t_field_name = TYPE_FN_FIELDLIST_NAME (t, i);
3137 char dem_opname[64];
3138
3139 if (strncmp (t_field_name, "__", 2) == 0
3140 || strncmp (t_field_name, "op", 2) == 0
3141 || strncmp (t_field_name, "type", 4) == 0)
3142 {
3143 if (cplus_demangle_opname (t_field_name,
3144 dem_opname, DMGL_ANSI))
3145 t_field_name = dem_opname;
3146 else if (cplus_demangle_opname (t_field_name,
3147 dem_opname, 0))
3148 t_field_name = dem_opname;
3149 }
3150 if (t_field_name && strcmp (t_field_name, name) == 0)
3151 {
3152 int j;
3153 int len = TYPE_FN_FIELDLIST_LENGTH (t, i);
3154 struct fn_field *f = TYPE_FN_FIELDLIST1 (t, i);
3155
3156 check_stub_method_group (t, i);
3157
3158 if (intype)
3159 {
3160 for (j = 0; j < len; ++j)
3161 {
3162 if (compare_parameters (TYPE_FN_FIELD_TYPE (f, j), intype, 0)
3163 || compare_parameters (TYPE_FN_FIELD_TYPE (f, j), intype, 1))
3164 break;
3165 }
3166
3167 if (j == len)
3168 error (_("no member function matches that type instantiation"));
3169 }
3170 else
3171 {
3172 int ii;
3173
3174 j = -1;
3175 for (ii = 0; ii < TYPE_FN_FIELDLIST_LENGTH (t, i);
3176 ++ii)
3177 {
3178 /* Skip artificial methods. This is necessary if,
3179 for example, the user wants to "print
3180 subclass::subclass" with only one user-defined
3181 constructor. There is no ambiguity in this
3182 case. */
3183 if (TYPE_FN_FIELD_ARTIFICIAL (f, ii))
3184 continue;
3185
3186 /* Desired method is ambiguous if more than one
3187 method is defined. */
3188 if (j != -1)
3189 error (_("non-unique member `%s' requires type instantiation"), name);
3190
3191 j = ii;
3192 }
3193 }
3194
3195 if (TYPE_FN_FIELD_STATIC_P (f, j))
3196 {
3197 struct symbol *s =
3198 lookup_symbol (TYPE_FN_FIELD_PHYSNAME (f, j),
3199 0, VAR_DOMAIN, 0);
3200
3201 if (s == NULL)
3202 return NULL;
3203
3204 if (want_address)
3205 return value_addr (read_var_value (s, 0));
3206 else
3207 return read_var_value (s, 0);
3208 }
3209
3210 if (TYPE_FN_FIELD_VIRTUAL_P (f, j))
3211 {
3212 if (want_address)
3213 {
3214 result = allocate_value
3215 (lookup_methodptr_type (TYPE_FN_FIELD_TYPE (f, j)));
3216 cplus_make_method_ptr (value_type (result),
3217 value_contents_writeable (result),
3218 TYPE_FN_FIELD_VOFFSET (f, j), 1);
3219 }
3220 else if (noside == EVAL_AVOID_SIDE_EFFECTS)
3221 return allocate_value (TYPE_FN_FIELD_TYPE (f, j));
3222 else
3223 error (_("Cannot reference virtual member function \"%s\""),
3224 name);
3225 }
3226 else
3227 {
3228 struct symbol *s =
3229 lookup_symbol (TYPE_FN_FIELD_PHYSNAME (f, j),
3230 0, VAR_DOMAIN, 0);
3231
3232 if (s == NULL)
3233 return NULL;
3234
3235 v = read_var_value (s, 0);
3236 if (!want_address)
3237 result = v;
3238 else
3239 {
3240 result = allocate_value (lookup_methodptr_type (TYPE_FN_FIELD_TYPE (f, j)));
3241 cplus_make_method_ptr (value_type (result),
3242 value_contents_writeable (result),
3243 value_address (v), 0);
3244 }
3245 }
3246 return result;
3247 }
3248 }
3249 for (i = TYPE_N_BASECLASSES (t) - 1; i >= 0; i--)
3250 {
3251 struct value *v;
3252 int base_offset;
3253
3254 if (BASETYPE_VIA_VIRTUAL (t, i))
3255 base_offset = 0;
3256 else
3257 base_offset = TYPE_BASECLASS_BITPOS (t, i) / 8;
3258 v = value_struct_elt_for_reference (domain,
3259 offset + base_offset,
3260 TYPE_BASECLASS (t, i),
3261 name, intype,
3262 want_address, noside);
3263 if (v)
3264 return v;
3265 }
3266
3267 /* As a last chance, pretend that CURTYPE is a namespace, and look
3268 it up that way; this (frequently) works for types nested inside
3269 classes. */
3270
3271 return value_maybe_namespace_elt (curtype, name,
3272 want_address, noside);
3273 }
3274
3275 /* C++: Return the member NAME of the namespace given by the type
3276 CURTYPE. */
3277
3278 static struct value *
3279 value_namespace_elt (const struct type *curtype,
3280 char *name, int want_address,
3281 enum noside noside)
3282 {
3283 struct value *retval = value_maybe_namespace_elt (curtype, name,
3284 want_address,
3285 noside);
3286
3287 if (retval == NULL)
3288 error (_("No symbol \"%s\" in namespace \"%s\"."),
3289 name, TYPE_TAG_NAME (curtype));
3290
3291 return retval;
3292 }
3293
3294 /* A helper function used by value_namespace_elt and
3295 value_struct_elt_for_reference. It looks up NAME inside the
3296 context CURTYPE; this works if CURTYPE is a namespace or if CURTYPE
3297 is a class and NAME refers to a type in CURTYPE itself (as opposed
3298 to, say, some base class of CURTYPE). */
3299
3300 static struct value *
3301 value_maybe_namespace_elt (const struct type *curtype,
3302 char *name, int want_address,
3303 enum noside noside)
3304 {
3305 const char *namespace_name = TYPE_TAG_NAME (curtype);
3306 struct symbol *sym;
3307 struct value *result;
3308
3309 sym = cp_lookup_symbol_namespace (namespace_name, name,
3310 get_selected_block (0), VAR_DOMAIN);
3311
3312 if (sym == NULL)
3313 {
3314 char *concatenated_name = alloca (strlen (namespace_name) + 2
3315 + strlen (name) + 1);
3316
3317 sprintf (concatenated_name, "%s::%s", namespace_name, name);
3318 sym = lookup_static_symbol_aux (concatenated_name, VAR_DOMAIN);
3319 }
3320
3321 if (sym == NULL)
3322 return NULL;
3323 else if ((noside == EVAL_AVOID_SIDE_EFFECTS)
3324 && (SYMBOL_CLASS (sym) == LOC_TYPEDEF))
3325 result = allocate_value (SYMBOL_TYPE (sym));
3326 else
3327 result = value_of_variable (sym, get_selected_block (0));
3328
3329 if (result && want_address)
3330 result = value_addr (result);
3331
3332 return result;
3333 }
3334
3335 /* Given a pointer value V, find the real (RTTI) type of the object it
3336 points to.
3337
3338 Other parameters FULL, TOP, USING_ENC as with value_rtti_type()
3339 and refer to the values computed for the object pointed to. */
3340
3341 struct type *
3342 value_rtti_target_type (struct value *v, int *full,
3343 int *top, int *using_enc)
3344 {
3345 struct value *target;
3346
3347 target = value_ind (v);
3348
3349 return value_rtti_type (target, full, top, using_enc);
3350 }
3351
3352 /* Given a value pointed to by ARGP, check its real run-time type, and
3353 if that is different from the enclosing type, create a new value
3354 using the real run-time type as the enclosing type (and of the same
3355 type as ARGP) and return it, with the embedded offset adjusted to
3356 be the correct offset to the enclosed object. RTYPE is the type,
3357 and XFULL, XTOP, and XUSING_ENC are the other parameters, computed
3358 by value_rtti_type(). If these are available, they can be supplied
3359 and a second call to value_rtti_type() is avoided. (Pass RTYPE ==
3360 NULL if they're not available. */
3361
3362 struct value *
3363 value_full_object (struct value *argp,
3364 struct type *rtype,
3365 int xfull, int xtop,
3366 int xusing_enc)
3367 {
3368 struct type *real_type;
3369 int full = 0;
3370 int top = -1;
3371 int using_enc = 0;
3372 struct value *new_val;
3373
3374 if (rtype)
3375 {
3376 real_type = rtype;
3377 full = xfull;
3378 top = xtop;
3379 using_enc = xusing_enc;
3380 }
3381 else
3382 real_type = value_rtti_type (argp, &full, &top, &using_enc);
3383
3384 /* If no RTTI data, or if object is already complete, do nothing. */
3385 if (!real_type || real_type == value_enclosing_type (argp))
3386 return argp;
3387
3388 /* If we have the full object, but for some reason the enclosing
3389 type is wrong, set it. */
3390 /* pai: FIXME -- sounds iffy */
3391 if (full)
3392 {
3393 argp = value_change_enclosing_type (argp, real_type);
3394 return argp;
3395 }
3396
3397 /* Check if object is in memory */
3398 if (VALUE_LVAL (argp) != lval_memory)
3399 {
3400 warning (_("Couldn't retrieve complete object of RTTI type %s; object may be in register(s)."),
3401 TYPE_NAME (real_type));
3402
3403 return argp;
3404 }
3405
3406 /* All other cases -- retrieve the complete object. */
3407 /* Go back by the computed top_offset from the beginning of the
3408 object, adjusting for the embedded offset of argp if that's what
3409 value_rtti_type used for its computation. */
3410 new_val = value_at_lazy (real_type, value_address (argp) - top +
3411 (using_enc ? 0 : value_embedded_offset (argp)));
3412 deprecated_set_value_type (new_val, value_type (argp));
3413 set_value_embedded_offset (new_val, (using_enc
3414 ? top + value_embedded_offset (argp)
3415 : top));
3416 return new_val;
3417 }
3418
3419
3420 /* Return the value of the local variable, if one exists.
3421 Flag COMPLAIN signals an error if the request is made in an
3422 inappropriate context. */
3423
3424 struct value *
3425 value_of_local (const char *name, int complain)
3426 {
3427 struct symbol *func, *sym;
3428 struct block *b;
3429 struct value * ret;
3430 struct frame_info *frame;
3431
3432 if (complain)
3433 frame = get_selected_frame (_("no frame selected"));
3434 else
3435 {
3436 frame = deprecated_safe_get_selected_frame ();
3437 if (frame == 0)
3438 return 0;
3439 }
3440
3441 func = get_frame_function (frame);
3442 if (!func)
3443 {
3444 if (complain)
3445 error (_("no `%s' in nameless context"), name);
3446 else
3447 return 0;
3448 }
3449
3450 b = SYMBOL_BLOCK_VALUE (func);
3451 if (dict_empty (BLOCK_DICT (b)))
3452 {
3453 if (complain)
3454 error (_("no args, no `%s'"), name);
3455 else
3456 return 0;
3457 }
3458
3459 /* Calling lookup_block_symbol is necessary to get the LOC_REGISTER
3460 symbol instead of the LOC_ARG one (if both exist). */
3461 sym = lookup_block_symbol (b, name, VAR_DOMAIN);
3462 if (sym == NULL)
3463 {
3464 if (complain)
3465 error (_("current stack frame does not contain a variable named `%s'"),
3466 name);
3467 else
3468 return NULL;
3469 }
3470
3471 ret = read_var_value (sym, frame);
3472 if (ret == 0 && complain)
3473 error (_("`%s' argument unreadable"), name);
3474 return ret;
3475 }
3476
3477 /* C++/Objective-C: return the value of the class instance variable,
3478 if one exists. Flag COMPLAIN signals an error if the request is
3479 made in an inappropriate context. */
3480
3481 struct value *
3482 value_of_this (int complain)
3483 {
3484 if (!current_language->la_name_of_this)
3485 return 0;
3486 return value_of_local (current_language->la_name_of_this, complain);
3487 }
3488
3489 /* Create a slice (sub-string, sub-array) of ARRAY, that is LENGTH
3490 elements long, starting at LOWBOUND. The result has the same lower
3491 bound as the original ARRAY. */
3492
3493 struct value *
3494 value_slice (struct value *array, int lowbound, int length)
3495 {
3496 struct type *slice_range_type, *slice_type, *range_type;
3497 LONGEST lowerbound, upperbound;
3498 struct value *slice;
3499 struct type *array_type;
3500
3501 array_type = check_typedef (value_type (array));
3502 if (TYPE_CODE (array_type) != TYPE_CODE_ARRAY
3503 && TYPE_CODE (array_type) != TYPE_CODE_STRING
3504 && TYPE_CODE (array_type) != TYPE_CODE_BITSTRING)
3505 error (_("cannot take slice of non-array"));
3506
3507 range_type = TYPE_INDEX_TYPE (array_type);
3508 if (get_discrete_bounds (range_type, &lowerbound, &upperbound) < 0)
3509 error (_("slice from bad array or bitstring"));
3510
3511 if (lowbound < lowerbound || length < 0
3512 || lowbound + length - 1 > upperbound)
3513 error (_("slice out of range"));
3514
3515 /* FIXME-type-allocation: need a way to free this type when we are
3516 done with it. */
3517 slice_range_type = create_range_type ((struct type *) NULL,
3518 TYPE_TARGET_TYPE (range_type),
3519 lowbound,
3520 lowbound + length - 1);
3521 if (TYPE_CODE (array_type) == TYPE_CODE_BITSTRING)
3522 {
3523 int i;
3524
3525 slice_type = create_set_type ((struct type *) NULL,
3526 slice_range_type);
3527 TYPE_CODE (slice_type) = TYPE_CODE_BITSTRING;
3528 slice = value_zero (slice_type, not_lval);
3529
3530 for (i = 0; i < length; i++)
3531 {
3532 int element = value_bit_index (array_type,
3533 value_contents (array),
3534 lowbound + i);
3535
3536 if (element < 0)
3537 error (_("internal error accessing bitstring"));
3538 else if (element > 0)
3539 {
3540 int j = i % TARGET_CHAR_BIT;
3541
3542 if (gdbarch_bits_big_endian (get_type_arch (array_type)))
3543 j = TARGET_CHAR_BIT - 1 - j;
3544 value_contents_raw (slice)[i / TARGET_CHAR_BIT] |= (1 << j);
3545 }
3546 }
3547 /* We should set the address, bitssize, and bitspos, so the
3548 slice can be used on the LHS, but that may require extensions
3549 to value_assign. For now, just leave as a non_lval.
3550 FIXME. */
3551 }
3552 else
3553 {
3554 struct type *element_type = TYPE_TARGET_TYPE (array_type);
3555 LONGEST offset =
3556 (lowbound - lowerbound) * TYPE_LENGTH (check_typedef (element_type));
3557
3558 slice_type = create_array_type ((struct type *) NULL,
3559 element_type,
3560 slice_range_type);
3561 TYPE_CODE (slice_type) = TYPE_CODE (array_type);
3562
3563 if (VALUE_LVAL (array) == lval_memory && value_lazy (array))
3564 slice = allocate_value_lazy (slice_type);
3565 else
3566 {
3567 slice = allocate_value (slice_type);
3568 memcpy (value_contents_writeable (slice),
3569 value_contents (array) + offset,
3570 TYPE_LENGTH (slice_type));
3571 }
3572
3573 set_value_component_location (slice, array);
3574 VALUE_FRAME_ID (slice) = VALUE_FRAME_ID (array);
3575 set_value_offset (slice, value_offset (array) + offset);
3576 }
3577 return slice;
3578 }
3579
3580 /* Create a value for a FORTRAN complex number. Currently most of the
3581 time values are coerced to COMPLEX*16 (i.e. a complex number
3582 composed of 2 doubles. This really should be a smarter routine
3583 that figures out precision inteligently as opposed to assuming
3584 doubles. FIXME: fmb */
3585
3586 struct value *
3587 value_literal_complex (struct value *arg1,
3588 struct value *arg2,
3589 struct type *type)
3590 {
3591 struct value *val;
3592 struct type *real_type = TYPE_TARGET_TYPE (type);
3593
3594 val = allocate_value (type);
3595 arg1 = value_cast (real_type, arg1);
3596 arg2 = value_cast (real_type, arg2);
3597
3598 memcpy (value_contents_raw (val),
3599 value_contents (arg1), TYPE_LENGTH (real_type));
3600 memcpy (value_contents_raw (val) + TYPE_LENGTH (real_type),
3601 value_contents (arg2), TYPE_LENGTH (real_type));
3602 return val;
3603 }
3604
3605 /* Cast a value into the appropriate complex data type. */
3606
3607 static struct value *
3608 cast_into_complex (struct type *type, struct value *val)
3609 {
3610 struct type *real_type = TYPE_TARGET_TYPE (type);
3611
3612 if (TYPE_CODE (value_type (val)) == TYPE_CODE_COMPLEX)
3613 {
3614 struct type *val_real_type = TYPE_TARGET_TYPE (value_type (val));
3615 struct value *re_val = allocate_value (val_real_type);
3616 struct value *im_val = allocate_value (val_real_type);
3617
3618 memcpy (value_contents_raw (re_val),
3619 value_contents (val), TYPE_LENGTH (val_real_type));
3620 memcpy (value_contents_raw (im_val),
3621 value_contents (val) + TYPE_LENGTH (val_real_type),
3622 TYPE_LENGTH (val_real_type));
3623
3624 return value_literal_complex (re_val, im_val, type);
3625 }
3626 else if (TYPE_CODE (value_type (val)) == TYPE_CODE_FLT
3627 || TYPE_CODE (value_type (val)) == TYPE_CODE_INT)
3628 return value_literal_complex (val,
3629 value_zero (real_type, not_lval),
3630 type);
3631 else
3632 error (_("cannot cast non-number to complex"));
3633 }
3634
3635 void
3636 _initialize_valops (void)
3637 {
3638 add_setshow_boolean_cmd ("overload-resolution", class_support,
3639 &overload_resolution, _("\
3640 Set overload resolution in evaluating C++ functions."), _("\
3641 Show overload resolution in evaluating C++ functions."),
3642 NULL, NULL,
3643 show_overload_resolution,
3644 &setlist, &showlist);
3645 overload_resolution = 1;
3646 }