valops.c revision 1.1.1.1 1 /* Perform non-arithmetic operations on values, for GDB.
2
3 Copyright (C) 1986-2014 Free Software Foundation, Inc.
4
5 This file is part of GDB.
6
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 3 of the License, or
10 (at your option) any later version.
11
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
16
17 You should have received a copy of the GNU General Public License
18 along with this program. If not, see <http://www.gnu.org/licenses/>. */
19
20 #include "defs.h"
21 #include "symtab.h"
22 #include "gdbtypes.h"
23 #include "value.h"
24 #include "frame.h"
25 #include "inferior.h"
26 #include "gdbcore.h"
27 #include "target.h"
28 #include "demangle.h"
29 #include "language.h"
30 #include "gdbcmd.h"
31 #include "regcache.h"
32 #include "cp-abi.h"
33 #include "block.h"
34 #include "infcall.h"
35 #include "dictionary.h"
36 #include "cp-support.h"
37 #include "dfp.h"
38 #include "tracepoint.h"
39 #include <errno.h>
40 #include <string.h>
41 #include "gdb_assert.h"
42 #include "observer.h"
43 #include "objfiles.h"
44 #include "exceptions.h"
45
46 extern unsigned int overload_debug;
47 /* Local functions. */
48
49 static int typecmp (int staticp, int varargs, int nargs,
50 struct field t1[], struct value *t2[]);
51
52 static struct value *search_struct_field (const char *, struct value *,
53 int, struct type *, int);
54
55 static struct value *search_struct_method (const char *, struct value **,
56 struct value **,
57 int, int *, struct type *);
58
59 static int find_oload_champ_namespace (struct value **, int,
60 const char *, const char *,
61 struct symbol ***,
62 struct badness_vector **,
63 const int no_adl);
64
65 static
66 int find_oload_champ_namespace_loop (struct value **, int,
67 const char *, const char *,
68 int, struct symbol ***,
69 struct badness_vector **, int *,
70 const int no_adl);
71
72 static int find_oload_champ (struct value **, int, int, int,
73 struct fn_field *, struct symbol **,
74 struct badness_vector **);
75
76 static int oload_method_static (int, struct fn_field *, int);
77
78 enum oload_classification { STANDARD, NON_STANDARD, INCOMPATIBLE };
79
80 static enum
81 oload_classification classify_oload_match (struct badness_vector *,
82 int, int);
83
84 static struct value *value_struct_elt_for_reference (struct type *,
85 int, struct type *,
86 char *,
87 struct type *,
88 int, enum noside);
89
90 static struct value *value_namespace_elt (const struct type *,
91 char *, int , enum noside);
92
93 static struct value *value_maybe_namespace_elt (const struct type *,
94 char *, int,
95 enum noside);
96
97 static CORE_ADDR allocate_space_in_inferior (int);
98
99 static struct value *cast_into_complex (struct type *, struct value *);
100
101 static struct fn_field *find_method_list (struct value **, const char *,
102 int, struct type *, int *,
103 struct type **, int *);
104
105 void _initialize_valops (void);
106
107 #if 0
108 /* Flag for whether we want to abandon failed expression evals by
109 default. */
110
111 static int auto_abandon = 0;
112 #endif
113
114 int overload_resolution = 0;
115 static void
116 show_overload_resolution (struct ui_file *file, int from_tty,
117 struct cmd_list_element *c,
118 const char *value)
119 {
120 fprintf_filtered (file, _("Overload resolution in evaluating "
121 "C++ functions is %s.\n"),
122 value);
123 }
124
125 /* Find the address of function name NAME in the inferior. If OBJF_P
126 is non-NULL, *OBJF_P will be set to the OBJFILE where the function
127 is defined. */
128
129 struct value *
130 find_function_in_inferior (const char *name, struct objfile **objf_p)
131 {
132 struct symbol *sym;
133
134 sym = lookup_symbol (name, 0, VAR_DOMAIN, 0);
135 if (sym != NULL)
136 {
137 if (SYMBOL_CLASS (sym) != LOC_BLOCK)
138 {
139 error (_("\"%s\" exists in this program but is not a function."),
140 name);
141 }
142
143 if (objf_p)
144 *objf_p = SYMBOL_SYMTAB (sym)->objfile;
145
146 return value_of_variable (sym, NULL);
147 }
148 else
149 {
150 struct bound_minimal_symbol msymbol =
151 lookup_bound_minimal_symbol (name);
152
153 if (msymbol.minsym != NULL)
154 {
155 struct objfile *objfile = msymbol.objfile;
156 struct gdbarch *gdbarch = get_objfile_arch (objfile);
157
158 struct type *type;
159 CORE_ADDR maddr;
160 type = lookup_pointer_type (builtin_type (gdbarch)->builtin_char);
161 type = lookup_function_type (type);
162 type = lookup_pointer_type (type);
163 maddr = SYMBOL_VALUE_ADDRESS (msymbol.minsym);
164
165 if (objf_p)
166 *objf_p = objfile;
167
168 return value_from_pointer (type, maddr);
169 }
170 else
171 {
172 if (!target_has_execution)
173 error (_("evaluation of this expression "
174 "requires the target program to be active"));
175 else
176 error (_("evaluation of this expression requires the "
177 "program to have a function \"%s\"."),
178 name);
179 }
180 }
181 }
182
183 /* Allocate NBYTES of space in the inferior using the inferior's
184 malloc and return a value that is a pointer to the allocated
185 space. */
186
187 struct value *
188 value_allocate_space_in_inferior (int len)
189 {
190 struct objfile *objf;
191 struct value *val = find_function_in_inferior ("malloc", &objf);
192 struct gdbarch *gdbarch = get_objfile_arch (objf);
193 struct value *blocklen;
194
195 blocklen = value_from_longest (builtin_type (gdbarch)->builtin_int, len);
196 val = call_function_by_hand (val, 1, &blocklen);
197 if (value_logical_not (val))
198 {
199 if (!target_has_execution)
200 error (_("No memory available to program now: "
201 "you need to start the target first"));
202 else
203 error (_("No memory available to program: call to malloc failed"));
204 }
205 return val;
206 }
207
208 static CORE_ADDR
209 allocate_space_in_inferior (int len)
210 {
211 return value_as_long (value_allocate_space_in_inferior (len));
212 }
213
214 /* Cast struct value VAL to type TYPE and return as a value.
215 Both type and val must be of TYPE_CODE_STRUCT or TYPE_CODE_UNION
216 for this to work. Typedef to one of the codes is permitted.
217 Returns NULL if the cast is neither an upcast nor a downcast. */
218
219 static struct value *
220 value_cast_structs (struct type *type, struct value *v2)
221 {
222 struct type *t1;
223 struct type *t2;
224 struct value *v;
225
226 gdb_assert (type != NULL && v2 != NULL);
227
228 t1 = check_typedef (type);
229 t2 = check_typedef (value_type (v2));
230
231 /* Check preconditions. */
232 gdb_assert ((TYPE_CODE (t1) == TYPE_CODE_STRUCT
233 || TYPE_CODE (t1) == TYPE_CODE_UNION)
234 && !!"Precondition is that type is of STRUCT or UNION kind.");
235 gdb_assert ((TYPE_CODE (t2) == TYPE_CODE_STRUCT
236 || TYPE_CODE (t2) == TYPE_CODE_UNION)
237 && !!"Precondition is that value is of STRUCT or UNION kind");
238
239 if (TYPE_NAME (t1) != NULL
240 && TYPE_NAME (t2) != NULL
241 && !strcmp (TYPE_NAME (t1), TYPE_NAME (t2)))
242 return NULL;
243
244 /* Upcasting: look in the type of the source to see if it contains the
245 type of the target as a superclass. If so, we'll need to
246 offset the pointer rather than just change its type. */
247 if (TYPE_NAME (t1) != NULL)
248 {
249 v = search_struct_field (type_name_no_tag (t1),
250 v2, 0, t2, 1);
251 if (v)
252 return v;
253 }
254
255 /* Downcasting: look in the type of the target to see if it contains the
256 type of the source as a superclass. If so, we'll need to
257 offset the pointer rather than just change its type. */
258 if (TYPE_NAME (t2) != NULL)
259 {
260 /* Try downcasting using the run-time type of the value. */
261 int full, top, using_enc;
262 struct type *real_type;
263
264 real_type = value_rtti_type (v2, &full, &top, &using_enc);
265 if (real_type)
266 {
267 v = value_full_object (v2, real_type, full, top, using_enc);
268 v = value_at_lazy (real_type, value_address (v));
269
270 /* We might be trying to cast to the outermost enclosing
271 type, in which case search_struct_field won't work. */
272 if (TYPE_NAME (real_type) != NULL
273 && !strcmp (TYPE_NAME (real_type), TYPE_NAME (t1)))
274 return v;
275
276 v = search_struct_field (type_name_no_tag (t2), v, 0, real_type, 1);
277 if (v)
278 return v;
279 }
280
281 /* Try downcasting using information from the destination type
282 T2. This wouldn't work properly for classes with virtual
283 bases, but those were handled above. */
284 v = search_struct_field (type_name_no_tag (t2),
285 value_zero (t1, not_lval), 0, t1, 1);
286 if (v)
287 {
288 /* Downcasting is possible (t1 is superclass of v2). */
289 CORE_ADDR addr2 = value_address (v2);
290
291 addr2 -= value_address (v) + value_embedded_offset (v);
292 return value_at (type, addr2);
293 }
294 }
295
296 return NULL;
297 }
298
299 /* Cast one pointer or reference type to another. Both TYPE and
300 the type of ARG2 should be pointer types, or else both should be
301 reference types. If SUBCLASS_CHECK is non-zero, this will force a
302 check to see whether TYPE is a superclass of ARG2's type. If
303 SUBCLASS_CHECK is zero, then the subclass check is done only when
304 ARG2 is itself non-zero. Returns the new pointer or reference. */
305
306 struct value *
307 value_cast_pointers (struct type *type, struct value *arg2,
308 int subclass_check)
309 {
310 struct type *type1 = check_typedef (type);
311 struct type *type2 = check_typedef (value_type (arg2));
312 struct type *t1 = check_typedef (TYPE_TARGET_TYPE (type1));
313 struct type *t2 = check_typedef (TYPE_TARGET_TYPE (type2));
314
315 if (TYPE_CODE (t1) == TYPE_CODE_STRUCT
316 && TYPE_CODE (t2) == TYPE_CODE_STRUCT
317 && (subclass_check || !value_logical_not (arg2)))
318 {
319 struct value *v2;
320
321 if (TYPE_CODE (type2) == TYPE_CODE_REF)
322 v2 = coerce_ref (arg2);
323 else
324 v2 = value_ind (arg2);
325 gdb_assert (TYPE_CODE (check_typedef (value_type (v2)))
326 == TYPE_CODE_STRUCT && !!"Why did coercion fail?");
327 v2 = value_cast_structs (t1, v2);
328 /* At this point we have what we can have, un-dereference if needed. */
329 if (v2)
330 {
331 struct value *v = value_addr (v2);
332
333 deprecated_set_value_type (v, type);
334 return v;
335 }
336 }
337
338 /* No superclass found, just change the pointer type. */
339 arg2 = value_copy (arg2);
340 deprecated_set_value_type (arg2, type);
341 set_value_enclosing_type (arg2, type);
342 set_value_pointed_to_offset (arg2, 0); /* pai: chk_val */
343 return arg2;
344 }
345
346 /* Cast value ARG2 to type TYPE and return as a value.
347 More general than a C cast: accepts any two types of the same length,
348 and if ARG2 is an lvalue it can be cast into anything at all. */
349 /* In C++, casts may change pointer or object representations. */
350
351 struct value *
352 value_cast (struct type *type, struct value *arg2)
353 {
354 enum type_code code1;
355 enum type_code code2;
356 int scalar;
357 struct type *type2;
358
359 int convert_to_boolean = 0;
360
361 if (value_type (arg2) == type)
362 return arg2;
363
364 code1 = TYPE_CODE (check_typedef (type));
365
366 /* Check if we are casting struct reference to struct reference. */
367 if (code1 == TYPE_CODE_REF)
368 {
369 /* We dereference type; then we recurse and finally
370 we generate value of the given reference. Nothing wrong with
371 that. */
372 struct type *t1 = check_typedef (type);
373 struct type *dereftype = check_typedef (TYPE_TARGET_TYPE (t1));
374 struct value *val = value_cast (dereftype, arg2);
375
376 return value_ref (val);
377 }
378
379 code2 = TYPE_CODE (check_typedef (value_type (arg2)));
380
381 if (code2 == TYPE_CODE_REF)
382 /* We deref the value and then do the cast. */
383 return value_cast (type, coerce_ref (arg2));
384
385 CHECK_TYPEDEF (type);
386 code1 = TYPE_CODE (type);
387 arg2 = coerce_ref (arg2);
388 type2 = check_typedef (value_type (arg2));
389
390 /* You can't cast to a reference type. See value_cast_pointers
391 instead. */
392 gdb_assert (code1 != TYPE_CODE_REF);
393
394 /* A cast to an undetermined-length array_type, such as
395 (TYPE [])OBJECT, is treated like a cast to (TYPE [N])OBJECT,
396 where N is sizeof(OBJECT)/sizeof(TYPE). */
397 if (code1 == TYPE_CODE_ARRAY)
398 {
399 struct type *element_type = TYPE_TARGET_TYPE (type);
400 unsigned element_length = TYPE_LENGTH (check_typedef (element_type));
401
402 if (element_length > 0 && TYPE_ARRAY_UPPER_BOUND_IS_UNDEFINED (type))
403 {
404 struct type *range_type = TYPE_INDEX_TYPE (type);
405 int val_length = TYPE_LENGTH (type2);
406 LONGEST low_bound, high_bound, new_length;
407
408 if (get_discrete_bounds (range_type, &low_bound, &high_bound) < 0)
409 low_bound = 0, high_bound = 0;
410 new_length = val_length / element_length;
411 if (val_length % element_length != 0)
412 warning (_("array element type size does not "
413 "divide object size in cast"));
414 /* FIXME-type-allocation: need a way to free this type when
415 we are done with it. */
416 range_type = create_range_type ((struct type *) NULL,
417 TYPE_TARGET_TYPE (range_type),
418 low_bound,
419 new_length + low_bound - 1);
420 deprecated_set_value_type (arg2,
421 create_array_type ((struct type *) NULL,
422 element_type,
423 range_type));
424 return arg2;
425 }
426 }
427
428 if (current_language->c_style_arrays
429 && TYPE_CODE (type2) == TYPE_CODE_ARRAY
430 && !TYPE_VECTOR (type2))
431 arg2 = value_coerce_array (arg2);
432
433 if (TYPE_CODE (type2) == TYPE_CODE_FUNC)
434 arg2 = value_coerce_function (arg2);
435
436 type2 = check_typedef (value_type (arg2));
437 code2 = TYPE_CODE (type2);
438
439 if (code1 == TYPE_CODE_COMPLEX)
440 return cast_into_complex (type, arg2);
441 if (code1 == TYPE_CODE_BOOL)
442 {
443 code1 = TYPE_CODE_INT;
444 convert_to_boolean = 1;
445 }
446 if (code1 == TYPE_CODE_CHAR)
447 code1 = TYPE_CODE_INT;
448 if (code2 == TYPE_CODE_BOOL || code2 == TYPE_CODE_CHAR)
449 code2 = TYPE_CODE_INT;
450
451 scalar = (code2 == TYPE_CODE_INT || code2 == TYPE_CODE_FLT
452 || code2 == TYPE_CODE_DECFLOAT || code2 == TYPE_CODE_ENUM
453 || code2 == TYPE_CODE_RANGE);
454
455 if ((code1 == TYPE_CODE_STRUCT || code1 == TYPE_CODE_UNION)
456 && (code2 == TYPE_CODE_STRUCT || code2 == TYPE_CODE_UNION)
457 && TYPE_NAME (type) != 0)
458 {
459 struct value *v = value_cast_structs (type, arg2);
460
461 if (v)
462 return v;
463 }
464
465 if (code1 == TYPE_CODE_FLT && scalar)
466 return value_from_double (type, value_as_double (arg2));
467 else if (code1 == TYPE_CODE_DECFLOAT && scalar)
468 {
469 enum bfd_endian byte_order = gdbarch_byte_order (get_type_arch (type));
470 int dec_len = TYPE_LENGTH (type);
471 gdb_byte dec[16];
472
473 if (code2 == TYPE_CODE_FLT)
474 decimal_from_floating (arg2, dec, dec_len, byte_order);
475 else if (code2 == TYPE_CODE_DECFLOAT)
476 decimal_convert (value_contents (arg2), TYPE_LENGTH (type2),
477 byte_order, dec, dec_len, byte_order);
478 else
479 /* The only option left is an integral type. */
480 decimal_from_integral (arg2, dec, dec_len, byte_order);
481
482 return value_from_decfloat (type, dec);
483 }
484 else if ((code1 == TYPE_CODE_INT || code1 == TYPE_CODE_ENUM
485 || code1 == TYPE_CODE_RANGE)
486 && (scalar || code2 == TYPE_CODE_PTR
487 || code2 == TYPE_CODE_MEMBERPTR))
488 {
489 LONGEST longest;
490
491 /* When we cast pointers to integers, we mustn't use
492 gdbarch_pointer_to_address to find the address the pointer
493 represents, as value_as_long would. GDB should evaluate
494 expressions just as the compiler would --- and the compiler
495 sees a cast as a simple reinterpretation of the pointer's
496 bits. */
497 if (code2 == TYPE_CODE_PTR)
498 longest = extract_unsigned_integer
499 (value_contents (arg2), TYPE_LENGTH (type2),
500 gdbarch_byte_order (get_type_arch (type2)));
501 else
502 longest = value_as_long (arg2);
503 return value_from_longest (type, convert_to_boolean ?
504 (LONGEST) (longest ? 1 : 0) : longest);
505 }
506 else if (code1 == TYPE_CODE_PTR && (code2 == TYPE_CODE_INT
507 || code2 == TYPE_CODE_ENUM
508 || code2 == TYPE_CODE_RANGE))
509 {
510 /* TYPE_LENGTH (type) is the length of a pointer, but we really
511 want the length of an address! -- we are really dealing with
512 addresses (i.e., gdb representations) not pointers (i.e.,
513 target representations) here.
514
515 This allows things like "print *(int *)0x01000234" to work
516 without printing a misleading message -- which would
517 otherwise occur when dealing with a target having two byte
518 pointers and four byte addresses. */
519
520 int addr_bit = gdbarch_addr_bit (get_type_arch (type2));
521 LONGEST longest = value_as_long (arg2);
522
523 if (addr_bit < sizeof (LONGEST) * HOST_CHAR_BIT)
524 {
525 if (longest >= ((LONGEST) 1 << addr_bit)
526 || longest <= -((LONGEST) 1 << addr_bit))
527 warning (_("value truncated"));
528 }
529 return value_from_longest (type, longest);
530 }
531 else if (code1 == TYPE_CODE_METHODPTR && code2 == TYPE_CODE_INT
532 && value_as_long (arg2) == 0)
533 {
534 struct value *result = allocate_value (type);
535
536 cplus_make_method_ptr (type, value_contents_writeable (result), 0, 0);
537 return result;
538 }
539 else if (code1 == TYPE_CODE_MEMBERPTR && code2 == TYPE_CODE_INT
540 && value_as_long (arg2) == 0)
541 {
542 /* The Itanium C++ ABI represents NULL pointers to members as
543 minus one, instead of biasing the normal case. */
544 return value_from_longest (type, -1);
545 }
546 else if (code1 == TYPE_CODE_ARRAY && TYPE_VECTOR (type)
547 && code2 == TYPE_CODE_ARRAY && TYPE_VECTOR (type2)
548 && TYPE_LENGTH (type) != TYPE_LENGTH (type2))
549 error (_("Cannot convert between vector values of different sizes"));
550 else if (code1 == TYPE_CODE_ARRAY && TYPE_VECTOR (type) && scalar
551 && TYPE_LENGTH (type) != TYPE_LENGTH (type2))
552 error (_("can only cast scalar to vector of same size"));
553 else if (code1 == TYPE_CODE_VOID)
554 {
555 return value_zero (type, not_lval);
556 }
557 else if (TYPE_LENGTH (type) == TYPE_LENGTH (type2))
558 {
559 if (code1 == TYPE_CODE_PTR && code2 == TYPE_CODE_PTR)
560 return value_cast_pointers (type, arg2, 0);
561
562 arg2 = value_copy (arg2);
563 deprecated_set_value_type (arg2, type);
564 set_value_enclosing_type (arg2, type);
565 set_value_pointed_to_offset (arg2, 0); /* pai: chk_val */
566 return arg2;
567 }
568 else if (VALUE_LVAL (arg2) == lval_memory)
569 return value_at_lazy (type, value_address (arg2));
570 else
571 {
572 error (_("Invalid cast."));
573 return 0;
574 }
575 }
576
577 /* The C++ reinterpret_cast operator. */
578
579 struct value *
580 value_reinterpret_cast (struct type *type, struct value *arg)
581 {
582 struct value *result;
583 struct type *real_type = check_typedef (type);
584 struct type *arg_type, *dest_type;
585 int is_ref = 0;
586 enum type_code dest_code, arg_code;
587
588 /* Do reference, function, and array conversion. */
589 arg = coerce_array (arg);
590
591 /* Attempt to preserve the type the user asked for. */
592 dest_type = type;
593
594 /* If we are casting to a reference type, transform
595 reinterpret_cast<T&>(V) to *reinterpret_cast<T*>(&V). */
596 if (TYPE_CODE (real_type) == TYPE_CODE_REF)
597 {
598 is_ref = 1;
599 arg = value_addr (arg);
600 dest_type = lookup_pointer_type (TYPE_TARGET_TYPE (dest_type));
601 real_type = lookup_pointer_type (real_type);
602 }
603
604 arg_type = value_type (arg);
605
606 dest_code = TYPE_CODE (real_type);
607 arg_code = TYPE_CODE (arg_type);
608
609 /* We can convert pointer types, or any pointer type to int, or int
610 type to pointer. */
611 if ((dest_code == TYPE_CODE_PTR && arg_code == TYPE_CODE_INT)
612 || (dest_code == TYPE_CODE_INT && arg_code == TYPE_CODE_PTR)
613 || (dest_code == TYPE_CODE_METHODPTR && arg_code == TYPE_CODE_INT)
614 || (dest_code == TYPE_CODE_INT && arg_code == TYPE_CODE_METHODPTR)
615 || (dest_code == TYPE_CODE_MEMBERPTR && arg_code == TYPE_CODE_INT)
616 || (dest_code == TYPE_CODE_INT && arg_code == TYPE_CODE_MEMBERPTR)
617 || (dest_code == arg_code
618 && (dest_code == TYPE_CODE_PTR
619 || dest_code == TYPE_CODE_METHODPTR
620 || dest_code == TYPE_CODE_MEMBERPTR)))
621 result = value_cast (dest_type, arg);
622 else
623 error (_("Invalid reinterpret_cast"));
624
625 if (is_ref)
626 result = value_cast (type, value_ref (value_ind (result)));
627
628 return result;
629 }
630
631 /* A helper for value_dynamic_cast. This implements the first of two
632 runtime checks: we iterate over all the base classes of the value's
633 class which are equal to the desired class; if only one of these
634 holds the value, then it is the answer. */
635
636 static int
637 dynamic_cast_check_1 (struct type *desired_type,
638 const gdb_byte *valaddr,
639 int embedded_offset,
640 CORE_ADDR address,
641 struct value *val,
642 struct type *search_type,
643 CORE_ADDR arg_addr,
644 struct type *arg_type,
645 struct value **result)
646 {
647 int i, result_count = 0;
648
649 for (i = 0; i < TYPE_N_BASECLASSES (search_type) && result_count < 2; ++i)
650 {
651 int offset = baseclass_offset (search_type, i, valaddr, embedded_offset,
652 address, val);
653
654 if (class_types_same_p (desired_type, TYPE_BASECLASS (search_type, i)))
655 {
656 if (address + embedded_offset + offset >= arg_addr
657 && address + embedded_offset + offset < arg_addr + TYPE_LENGTH (arg_type))
658 {
659 ++result_count;
660 if (!*result)
661 *result = value_at_lazy (TYPE_BASECLASS (search_type, i),
662 address + embedded_offset + offset);
663 }
664 }
665 else
666 result_count += dynamic_cast_check_1 (desired_type,
667 valaddr,
668 embedded_offset + offset,
669 address, val,
670 TYPE_BASECLASS (search_type, i),
671 arg_addr,
672 arg_type,
673 result);
674 }
675
676 return result_count;
677 }
678
679 /* A helper for value_dynamic_cast. This implements the second of two
680 runtime checks: we look for a unique public sibling class of the
681 argument's declared class. */
682
683 static int
684 dynamic_cast_check_2 (struct type *desired_type,
685 const gdb_byte *valaddr,
686 int embedded_offset,
687 CORE_ADDR address,
688 struct value *val,
689 struct type *search_type,
690 struct value **result)
691 {
692 int i, result_count = 0;
693
694 for (i = 0; i < TYPE_N_BASECLASSES (search_type) && result_count < 2; ++i)
695 {
696 int offset;
697
698 if (! BASETYPE_VIA_PUBLIC (search_type, i))
699 continue;
700
701 offset = baseclass_offset (search_type, i, valaddr, embedded_offset,
702 address, val);
703 if (class_types_same_p (desired_type, TYPE_BASECLASS (search_type, i)))
704 {
705 ++result_count;
706 if (*result == NULL)
707 *result = value_at_lazy (TYPE_BASECLASS (search_type, i),
708 address + embedded_offset + offset);
709 }
710 else
711 result_count += dynamic_cast_check_2 (desired_type,
712 valaddr,
713 embedded_offset + offset,
714 address, val,
715 TYPE_BASECLASS (search_type, i),
716 result);
717 }
718
719 return result_count;
720 }
721
722 /* The C++ dynamic_cast operator. */
723
724 struct value *
725 value_dynamic_cast (struct type *type, struct value *arg)
726 {
727 int full, top, using_enc;
728 struct type *resolved_type = check_typedef (type);
729 struct type *arg_type = check_typedef (value_type (arg));
730 struct type *class_type, *rtti_type;
731 struct value *result, *tem, *original_arg = arg;
732 CORE_ADDR addr;
733 int is_ref = TYPE_CODE (resolved_type) == TYPE_CODE_REF;
734
735 if (TYPE_CODE (resolved_type) != TYPE_CODE_PTR
736 && TYPE_CODE (resolved_type) != TYPE_CODE_REF)
737 error (_("Argument to dynamic_cast must be a pointer or reference type"));
738 if (TYPE_CODE (TYPE_TARGET_TYPE (resolved_type)) != TYPE_CODE_VOID
739 && TYPE_CODE (TYPE_TARGET_TYPE (resolved_type)) != TYPE_CODE_CLASS)
740 error (_("Argument to dynamic_cast must be pointer to class or `void *'"));
741
742 class_type = check_typedef (TYPE_TARGET_TYPE (resolved_type));
743 if (TYPE_CODE (resolved_type) == TYPE_CODE_PTR)
744 {
745 if (TYPE_CODE (arg_type) != TYPE_CODE_PTR
746 && ! (TYPE_CODE (arg_type) == TYPE_CODE_INT
747 && value_as_long (arg) == 0))
748 error (_("Argument to dynamic_cast does not have pointer type"));
749 if (TYPE_CODE (arg_type) == TYPE_CODE_PTR)
750 {
751 arg_type = check_typedef (TYPE_TARGET_TYPE (arg_type));
752 if (TYPE_CODE (arg_type) != TYPE_CODE_CLASS)
753 error (_("Argument to dynamic_cast does "
754 "not have pointer to class type"));
755 }
756
757 /* Handle NULL pointers. */
758 if (value_as_long (arg) == 0)
759 return value_zero (type, not_lval);
760
761 arg = value_ind (arg);
762 }
763 else
764 {
765 if (TYPE_CODE (arg_type) != TYPE_CODE_CLASS)
766 error (_("Argument to dynamic_cast does not have class type"));
767 }
768
769 /* If the classes are the same, just return the argument. */
770 if (class_types_same_p (class_type, arg_type))
771 return value_cast (type, arg);
772
773 /* If the target type is a unique base class of the argument's
774 declared type, just cast it. */
775 if (is_ancestor (class_type, arg_type))
776 {
777 if (is_unique_ancestor (class_type, arg))
778 return value_cast (type, original_arg);
779 error (_("Ambiguous dynamic_cast"));
780 }
781
782 rtti_type = value_rtti_type (arg, &full, &top, &using_enc);
783 if (! rtti_type)
784 error (_("Couldn't determine value's most derived type for dynamic_cast"));
785
786 /* Compute the most derived object's address. */
787 addr = value_address (arg);
788 if (full)
789 {
790 /* Done. */
791 }
792 else if (using_enc)
793 addr += top;
794 else
795 addr += top + value_embedded_offset (arg);
796
797 /* dynamic_cast<void *> means to return a pointer to the
798 most-derived object. */
799 if (TYPE_CODE (resolved_type) == TYPE_CODE_PTR
800 && TYPE_CODE (TYPE_TARGET_TYPE (resolved_type)) == TYPE_CODE_VOID)
801 return value_at_lazy (type, addr);
802
803 tem = value_at (type, addr);
804
805 /* The first dynamic check specified in 5.2.7. */
806 if (is_public_ancestor (arg_type, TYPE_TARGET_TYPE (resolved_type)))
807 {
808 if (class_types_same_p (rtti_type, TYPE_TARGET_TYPE (resolved_type)))
809 return tem;
810 result = NULL;
811 if (dynamic_cast_check_1 (TYPE_TARGET_TYPE (resolved_type),
812 value_contents_for_printing (tem),
813 value_embedded_offset (tem),
814 value_address (tem), tem,
815 rtti_type, addr,
816 arg_type,
817 &result) == 1)
818 return value_cast (type,
819 is_ref ? value_ref (result) : value_addr (result));
820 }
821
822 /* The second dynamic check specified in 5.2.7. */
823 result = NULL;
824 if (is_public_ancestor (arg_type, rtti_type)
825 && dynamic_cast_check_2 (TYPE_TARGET_TYPE (resolved_type),
826 value_contents_for_printing (tem),
827 value_embedded_offset (tem),
828 value_address (tem), 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 == lval_computed ? not_lval : lv);
847 return val;
848 }
849
850 /* Create a not_lval value of numeric type TYPE that is one, and return it. */
851
852 struct value *
853 value_one (struct type *type)
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 if (TYPE_CODE (type1) == TYPE_CODE_ARRAY && TYPE_VECTOR (type1))
875 {
876 struct type *eltype = check_typedef (TYPE_TARGET_TYPE (type1));
877 int i;
878 LONGEST low_bound, high_bound;
879 struct value *tmp;
880
881 if (!get_array_bounds (type1, &low_bound, &high_bound))
882 error (_("Could not determine the vector bounds"));
883
884 val = allocate_value (type);
885 for (i = 0; i < high_bound - low_bound + 1; i++)
886 {
887 tmp = value_one (eltype);
888 memcpy (value_contents_writeable (val) + i * TYPE_LENGTH (eltype),
889 value_contents_all (tmp), TYPE_LENGTH (eltype));
890 }
891 }
892 else
893 {
894 error (_("Not a numeric type."));
895 }
896
897 /* value_one result is never used for assignments to. */
898 gdb_assert (VALUE_LVAL (val) == not_lval);
899
900 return val;
901 }
902
903 /* Helper function for value_at, value_at_lazy, and value_at_lazy_stack. */
904
905 static struct value *
906 get_value_at (struct type *type, CORE_ADDR addr, int lazy)
907 {
908 struct value *val;
909
910 if (TYPE_CODE (check_typedef (type)) == TYPE_CODE_VOID)
911 error (_("Attempt to dereference a generic pointer."));
912
913 val = value_from_contents_and_address (type, NULL, addr);
914
915 if (!lazy)
916 value_fetch_lazy (val);
917
918 return val;
919 }
920
921 /* Return a value with type TYPE located at ADDR.
922
923 Call value_at only if the data needs to be fetched immediately;
924 if we can be 'lazy' and defer the fetch, perhaps indefinately, call
925 value_at_lazy instead. value_at_lazy simply records the address of
926 the data and sets the lazy-evaluation-required flag. The lazy flag
927 is tested in the value_contents macro, which is used if and when
928 the contents are actually required.
929
930 Note: value_at does *NOT* handle embedded offsets; perform such
931 adjustments before or after calling it. */
932
933 struct value *
934 value_at (struct type *type, CORE_ADDR addr)
935 {
936 return get_value_at (type, addr, 0);
937 }
938
939 /* Return a lazy value with type TYPE located at ADDR (cf. value_at). */
940
941 struct value *
942 value_at_lazy (struct type *type, CORE_ADDR addr)
943 {
944 return get_value_at (type, addr, 1);
945 }
946
947 void
948 read_value_memory (struct value *val, int embedded_offset,
949 int stack, CORE_ADDR memaddr,
950 gdb_byte *buffer, size_t length)
951 {
952 if (length)
953 {
954 VEC(mem_range_s) *available_memory;
955
956 if (!traceframe_available_memory (&available_memory, memaddr, length))
957 {
958 if (stack)
959 read_stack (memaddr, buffer, length);
960 else
961 read_memory (memaddr, buffer, length);
962 }
963 else
964 {
965 struct target_section_table *table;
966 struct cleanup *old_chain;
967 CORE_ADDR unavail;
968 mem_range_s *r;
969 int i;
970
971 /* Fallback to reading from read-only sections. */
972 table = target_get_section_table (&exec_ops);
973 available_memory =
974 section_table_available_memory (available_memory,
975 memaddr, length,
976 table->sections,
977 table->sections_end);
978
979 old_chain = make_cleanup (VEC_cleanup(mem_range_s),
980 &available_memory);
981
982 normalize_mem_ranges (available_memory);
983
984 /* Mark which bytes are unavailable, and read those which
985 are available. */
986
987 unavail = memaddr;
988
989 for (i = 0;
990 VEC_iterate (mem_range_s, available_memory, i, r);
991 i++)
992 {
993 if (mem_ranges_overlap (r->start, r->length,
994 memaddr, length))
995 {
996 CORE_ADDR lo1, hi1, lo2, hi2;
997 CORE_ADDR start, end;
998
999 /* Get the intersection window. */
1000 lo1 = memaddr;
1001 hi1 = memaddr + length;
1002 lo2 = r->start;
1003 hi2 = r->start + r->length;
1004 start = max (lo1, lo2);
1005 end = min (hi1, hi2);
1006
1007 gdb_assert (end - memaddr <= length);
1008
1009 if (start > unavail)
1010 mark_value_bytes_unavailable (val,
1011 (embedded_offset
1012 + unavail - memaddr),
1013 start - unavail);
1014 unavail = end;
1015
1016 read_memory (start, buffer + start - memaddr, end - start);
1017 }
1018 }
1019
1020 if (unavail != memaddr + length)
1021 mark_value_bytes_unavailable (val,
1022 embedded_offset + unavail - memaddr,
1023 (memaddr + length) - unavail);
1024
1025 do_cleanups (old_chain);
1026 }
1027 }
1028 }
1029
1030 /* Store the contents of FROMVAL into the location of TOVAL.
1031 Return a new value with the location of TOVAL and contents of FROMVAL. */
1032
1033 struct value *
1034 value_assign (struct value *toval, struct value *fromval)
1035 {
1036 struct type *type;
1037 struct value *val;
1038 struct frame_id old_frame;
1039
1040 if (!deprecated_value_modifiable (toval))
1041 error (_("Left operand of assignment is not a modifiable lvalue."));
1042
1043 toval = coerce_ref (toval);
1044
1045 type = value_type (toval);
1046 if (VALUE_LVAL (toval) != lval_internalvar)
1047 fromval = value_cast (type, fromval);
1048 else
1049 {
1050 /* Coerce arrays and functions to pointers, except for arrays
1051 which only live in GDB's storage. */
1052 if (!value_must_coerce_to_target (fromval))
1053 fromval = coerce_array (fromval);
1054 }
1055
1056 CHECK_TYPEDEF (type);
1057
1058 /* Since modifying a register can trash the frame chain, and
1059 modifying memory can trash the frame cache, we save the old frame
1060 and then restore the new frame afterwards. */
1061 old_frame = get_frame_id (deprecated_safe_get_selected_frame ());
1062
1063 switch (VALUE_LVAL (toval))
1064 {
1065 case lval_internalvar:
1066 set_internalvar (VALUE_INTERNALVAR (toval), fromval);
1067 return value_of_internalvar (get_type_arch (type),
1068 VALUE_INTERNALVAR (toval));
1069
1070 case lval_internalvar_component:
1071 {
1072 int offset = value_offset (toval);
1073
1074 /* Are we dealing with a bitfield?
1075
1076 It is important to mention that `value_parent (toval)' is
1077 non-NULL iff `value_bitsize (toval)' is non-zero. */
1078 if (value_bitsize (toval))
1079 {
1080 /* VALUE_INTERNALVAR below refers to the parent value, while
1081 the offset is relative to this parent value. */
1082 gdb_assert (value_parent (value_parent (toval)) == NULL);
1083 offset += value_offset (value_parent (toval));
1084 }
1085
1086 set_internalvar_component (VALUE_INTERNALVAR (toval),
1087 offset,
1088 value_bitpos (toval),
1089 value_bitsize (toval),
1090 fromval);
1091 }
1092 break;
1093
1094 case lval_memory:
1095 {
1096 const gdb_byte *dest_buffer;
1097 CORE_ADDR changed_addr;
1098 int changed_len;
1099 gdb_byte buffer[sizeof (LONGEST)];
1100
1101 if (value_bitsize (toval))
1102 {
1103 struct value *parent = value_parent (toval);
1104
1105 changed_addr = value_address (parent) + value_offset (toval);
1106 changed_len = (value_bitpos (toval)
1107 + value_bitsize (toval)
1108 + HOST_CHAR_BIT - 1)
1109 / HOST_CHAR_BIT;
1110
1111 /* If we can read-modify-write exactly the size of the
1112 containing type (e.g. short or int) then do so. This
1113 is safer for volatile bitfields mapped to hardware
1114 registers. */
1115 if (changed_len < TYPE_LENGTH (type)
1116 && TYPE_LENGTH (type) <= (int) sizeof (LONGEST)
1117 && ((LONGEST) changed_addr % TYPE_LENGTH (type)) == 0)
1118 changed_len = TYPE_LENGTH (type);
1119
1120 if (changed_len > (int) sizeof (LONGEST))
1121 error (_("Can't handle bitfields which "
1122 "don't fit in a %d bit word."),
1123 (int) sizeof (LONGEST) * HOST_CHAR_BIT);
1124
1125 read_memory (changed_addr, buffer, changed_len);
1126 modify_field (type, buffer, value_as_long (fromval),
1127 value_bitpos (toval), value_bitsize (toval));
1128 dest_buffer = buffer;
1129 }
1130 else
1131 {
1132 changed_addr = value_address (toval);
1133 changed_len = TYPE_LENGTH (type);
1134 dest_buffer = value_contents (fromval);
1135 }
1136
1137 write_memory_with_notification (changed_addr, dest_buffer, changed_len);
1138 }
1139 break;
1140
1141 case lval_register:
1142 {
1143 struct frame_info *frame;
1144 struct gdbarch *gdbarch;
1145 int value_reg;
1146
1147 /* Figure out which frame this is in currently. */
1148 frame = frame_find_by_id (VALUE_FRAME_ID (toval));
1149 value_reg = VALUE_REGNUM (toval);
1150
1151 if (!frame)
1152 error (_("Value being assigned to is no longer active."));
1153
1154 gdbarch = get_frame_arch (frame);
1155 if (gdbarch_convert_register_p (gdbarch, VALUE_REGNUM (toval), type))
1156 {
1157 /* If TOVAL is a special machine register requiring
1158 conversion of program values to a special raw
1159 format. */
1160 gdbarch_value_to_register (gdbarch, frame,
1161 VALUE_REGNUM (toval), type,
1162 value_contents (fromval));
1163 }
1164 else
1165 {
1166 if (value_bitsize (toval))
1167 {
1168 struct value *parent = value_parent (toval);
1169 int offset = value_offset (parent) + value_offset (toval);
1170 int changed_len;
1171 gdb_byte buffer[sizeof (LONGEST)];
1172 int optim, unavail;
1173
1174 changed_len = (value_bitpos (toval)
1175 + value_bitsize (toval)
1176 + HOST_CHAR_BIT - 1)
1177 / HOST_CHAR_BIT;
1178
1179 if (changed_len > (int) sizeof (LONGEST))
1180 error (_("Can't handle bitfields which "
1181 "don't fit in a %d bit word."),
1182 (int) sizeof (LONGEST) * HOST_CHAR_BIT);
1183
1184 if (!get_frame_register_bytes (frame, value_reg, offset,
1185 changed_len, buffer,
1186 &optim, &unavail))
1187 {
1188 if (optim)
1189 throw_error (OPTIMIZED_OUT_ERROR,
1190 _("value has been optimized out"));
1191 if (unavail)
1192 throw_error (NOT_AVAILABLE_ERROR,
1193 _("value is not available"));
1194 }
1195
1196 modify_field (type, buffer, value_as_long (fromval),
1197 value_bitpos (toval), value_bitsize (toval));
1198
1199 put_frame_register_bytes (frame, value_reg, offset,
1200 changed_len, buffer);
1201 }
1202 else
1203 {
1204 put_frame_register_bytes (frame, value_reg,
1205 value_offset (toval),
1206 TYPE_LENGTH (type),
1207 value_contents (fromval));
1208 }
1209 }
1210
1211 if (deprecated_register_changed_hook)
1212 deprecated_register_changed_hook (-1);
1213 break;
1214 }
1215
1216 case lval_computed:
1217 {
1218 const struct lval_funcs *funcs = value_computed_funcs (toval);
1219
1220 if (funcs->write != NULL)
1221 {
1222 funcs->write (toval, fromval);
1223 break;
1224 }
1225 }
1226 /* Fall through. */
1227
1228 default:
1229 error (_("Left operand of assignment is not an lvalue."));
1230 }
1231
1232 /* Assigning to the stack pointer, frame pointer, and other
1233 (architecture and calling convention specific) registers may
1234 cause the frame cache and regcache to be out of date. Assigning to memory
1235 also can. We just do this on all assignments to registers or
1236 memory, for simplicity's sake; I doubt the slowdown matters. */
1237 switch (VALUE_LVAL (toval))
1238 {
1239 case lval_memory:
1240 case lval_register:
1241 case lval_computed:
1242
1243 observer_notify_target_changed (¤t_target);
1244
1245 /* Having destroyed the frame cache, restore the selected
1246 frame. */
1247
1248 /* FIXME: cagney/2002-11-02: There has to be a better way of
1249 doing this. Instead of constantly saving/restoring the
1250 frame. Why not create a get_selected_frame() function that,
1251 having saved the selected frame's ID can automatically
1252 re-find the previously selected frame automatically. */
1253
1254 {
1255 struct frame_info *fi = frame_find_by_id (old_frame);
1256
1257 if (fi != NULL)
1258 select_frame (fi);
1259 }
1260
1261 break;
1262 default:
1263 break;
1264 }
1265
1266 /* If the field does not entirely fill a LONGEST, then zero the sign
1267 bits. If the field is signed, and is negative, then sign
1268 extend. */
1269 if ((value_bitsize (toval) > 0)
1270 && (value_bitsize (toval) < 8 * (int) sizeof (LONGEST)))
1271 {
1272 LONGEST fieldval = value_as_long (fromval);
1273 LONGEST valmask = (((ULONGEST) 1) << value_bitsize (toval)) - 1;
1274
1275 fieldval &= valmask;
1276 if (!TYPE_UNSIGNED (type)
1277 && (fieldval & (valmask ^ (valmask >> 1))))
1278 fieldval |= ~valmask;
1279
1280 fromval = value_from_longest (type, fieldval);
1281 }
1282
1283 /* The return value is a copy of TOVAL so it shares its location
1284 information, but its contents are updated from FROMVAL. This
1285 implies the returned value is not lazy, even if TOVAL was. */
1286 val = value_copy (toval);
1287 set_value_lazy (val, 0);
1288 memcpy (value_contents_raw (val), value_contents (fromval),
1289 TYPE_LENGTH (type));
1290
1291 /* We copy over the enclosing type and pointed-to offset from FROMVAL
1292 in the case of pointer types. For object types, the enclosing type
1293 and embedded offset must *not* be copied: the target object refered
1294 to by TOVAL retains its original dynamic type after assignment. */
1295 if (TYPE_CODE (type) == TYPE_CODE_PTR)
1296 {
1297 set_value_enclosing_type (val, value_enclosing_type (fromval));
1298 set_value_pointed_to_offset (val, value_pointed_to_offset (fromval));
1299 }
1300
1301 return val;
1302 }
1303
1304 /* Extend a value VAL to COUNT repetitions of its type. */
1305
1306 struct value *
1307 value_repeat (struct value *arg1, int count)
1308 {
1309 struct value *val;
1310
1311 if (VALUE_LVAL (arg1) != lval_memory)
1312 error (_("Only values in memory can be extended with '@'."));
1313 if (count < 1)
1314 error (_("Invalid number %d of repetitions."), count);
1315
1316 val = allocate_repeat_value (value_enclosing_type (arg1), count);
1317
1318 VALUE_LVAL (val) = lval_memory;
1319 set_value_address (val, value_address (arg1));
1320
1321 read_value_memory (val, 0, value_stack (val), value_address (val),
1322 value_contents_all_raw (val),
1323 TYPE_LENGTH (value_enclosing_type (val)));
1324
1325 return val;
1326 }
1327
1328 struct value *
1329 value_of_variable (struct symbol *var, const struct block *b)
1330 {
1331 struct frame_info *frame;
1332
1333 if (!symbol_read_needs_frame (var))
1334 frame = NULL;
1335 else if (!b)
1336 frame = get_selected_frame (_("No frame selected."));
1337 else
1338 {
1339 frame = block_innermost_frame (b);
1340 if (!frame)
1341 {
1342 if (BLOCK_FUNCTION (b) && !block_inlined_p (b)
1343 && SYMBOL_PRINT_NAME (BLOCK_FUNCTION (b)))
1344 error (_("No frame is currently executing in block %s."),
1345 SYMBOL_PRINT_NAME (BLOCK_FUNCTION (b)));
1346 else
1347 error (_("No frame is currently executing in specified block"));
1348 }
1349 }
1350
1351 return read_var_value (var, frame);
1352 }
1353
1354 struct value *
1355 address_of_variable (struct symbol *var, const struct block *b)
1356 {
1357 struct type *type = SYMBOL_TYPE (var);
1358 struct value *val;
1359
1360 /* Evaluate it first; if the result is a memory address, we're fine.
1361 Lazy evaluation pays off here. */
1362
1363 val = value_of_variable (var, b);
1364
1365 if ((VALUE_LVAL (val) == lval_memory && value_lazy (val))
1366 || TYPE_CODE (type) == TYPE_CODE_FUNC)
1367 {
1368 CORE_ADDR addr = value_address (val);
1369
1370 return value_from_pointer (lookup_pointer_type (type), addr);
1371 }
1372
1373 /* Not a memory address; check what the problem was. */
1374 switch (VALUE_LVAL (val))
1375 {
1376 case lval_register:
1377 {
1378 struct frame_info *frame;
1379 const char *regname;
1380
1381 frame = frame_find_by_id (VALUE_FRAME_ID (val));
1382 gdb_assert (frame);
1383
1384 regname = gdbarch_register_name (get_frame_arch (frame),
1385 VALUE_REGNUM (val));
1386 gdb_assert (regname && *regname);
1387
1388 error (_("Address requested for identifier "
1389 "\"%s\" which is in register $%s"),
1390 SYMBOL_PRINT_NAME (var), regname);
1391 break;
1392 }
1393
1394 default:
1395 error (_("Can't take address of \"%s\" which isn't an lvalue."),
1396 SYMBOL_PRINT_NAME (var));
1397 break;
1398 }
1399
1400 return val;
1401 }
1402
1403 /* Return one if VAL does not live in target memory, but should in order
1404 to operate on it. Otherwise return zero. */
1405
1406 int
1407 value_must_coerce_to_target (struct value *val)
1408 {
1409 struct type *valtype;
1410
1411 /* The only lval kinds which do not live in target memory. */
1412 if (VALUE_LVAL (val) != not_lval
1413 && VALUE_LVAL (val) != lval_internalvar)
1414 return 0;
1415
1416 valtype = check_typedef (value_type (val));
1417
1418 switch (TYPE_CODE (valtype))
1419 {
1420 case TYPE_CODE_ARRAY:
1421 return TYPE_VECTOR (valtype) ? 0 : 1;
1422 case TYPE_CODE_STRING:
1423 return 1;
1424 default:
1425 return 0;
1426 }
1427 }
1428
1429 /* Make sure that VAL lives in target memory if it's supposed to. For
1430 instance, strings are constructed as character arrays in GDB's
1431 storage, and this function copies them to the target. */
1432
1433 struct value *
1434 value_coerce_to_target (struct value *val)
1435 {
1436 LONGEST length;
1437 CORE_ADDR addr;
1438
1439 if (!value_must_coerce_to_target (val))
1440 return val;
1441
1442 length = TYPE_LENGTH (check_typedef (value_type (val)));
1443 addr = allocate_space_in_inferior (length);
1444 write_memory (addr, value_contents (val), length);
1445 return value_at_lazy (value_type (val), addr);
1446 }
1447
1448 /* Given a value which is an array, return a value which is a pointer
1449 to its first element, regardless of whether or not the array has a
1450 nonzero lower bound.
1451
1452 FIXME: A previous comment here indicated that this routine should
1453 be substracting the array's lower bound. It's not clear to me that
1454 this is correct. Given an array subscripting operation, it would
1455 certainly work to do the adjustment here, essentially computing:
1456
1457 (&array[0] - (lowerbound * sizeof array[0])) + (index * sizeof array[0])
1458
1459 However I believe a more appropriate and logical place to account
1460 for the lower bound is to do so in value_subscript, essentially
1461 computing:
1462
1463 (&array[0] + ((index - lowerbound) * sizeof array[0]))
1464
1465 As further evidence consider what would happen with operations
1466 other than array subscripting, where the caller would get back a
1467 value that had an address somewhere before the actual first element
1468 of the array, and the information about the lower bound would be
1469 lost because of the coercion to pointer type. */
1470
1471 struct value *
1472 value_coerce_array (struct value *arg1)
1473 {
1474 struct type *type = check_typedef (value_type (arg1));
1475
1476 /* If the user tries to do something requiring a pointer with an
1477 array that has not yet been pushed to the target, then this would
1478 be a good time to do so. */
1479 arg1 = value_coerce_to_target (arg1);
1480
1481 if (VALUE_LVAL (arg1) != lval_memory)
1482 error (_("Attempt to take address of value not located in memory."));
1483
1484 return value_from_pointer (lookup_pointer_type (TYPE_TARGET_TYPE (type)),
1485 value_address (arg1));
1486 }
1487
1488 /* Given a value which is a function, return a value which is a pointer
1489 to it. */
1490
1491 struct value *
1492 value_coerce_function (struct value *arg1)
1493 {
1494 struct value *retval;
1495
1496 if (VALUE_LVAL (arg1) != lval_memory)
1497 error (_("Attempt to take address of value not located in memory."));
1498
1499 retval = value_from_pointer (lookup_pointer_type (value_type (arg1)),
1500 value_address (arg1));
1501 return retval;
1502 }
1503
1504 /* Return a pointer value for the object for which ARG1 is the
1505 contents. */
1506
1507 struct value *
1508 value_addr (struct value *arg1)
1509 {
1510 struct value *arg2;
1511 struct type *type = check_typedef (value_type (arg1));
1512
1513 if (TYPE_CODE (type) == TYPE_CODE_REF)
1514 {
1515 /* Copy the value, but change the type from (T&) to (T*). We
1516 keep the same location information, which is efficient, and
1517 allows &(&X) to get the location containing the reference. */
1518 arg2 = value_copy (arg1);
1519 deprecated_set_value_type (arg2,
1520 lookup_pointer_type (TYPE_TARGET_TYPE (type)));
1521 return arg2;
1522 }
1523 if (TYPE_CODE (type) == TYPE_CODE_FUNC)
1524 return value_coerce_function (arg1);
1525
1526 /* If this is an array that has not yet been pushed to the target,
1527 then this would be a good time to force it to memory. */
1528 arg1 = value_coerce_to_target (arg1);
1529
1530 if (VALUE_LVAL (arg1) != lval_memory)
1531 error (_("Attempt to take address of value not located in memory."));
1532
1533 /* Get target memory address. */
1534 arg2 = value_from_pointer (lookup_pointer_type (value_type (arg1)),
1535 (value_address (arg1)
1536 + value_embedded_offset (arg1)));
1537
1538 /* This may be a pointer to a base subobject; so remember the
1539 full derived object's type ... */
1540 set_value_enclosing_type (arg2,
1541 lookup_pointer_type (value_enclosing_type (arg1)));
1542 /* ... and also the relative position of the subobject in the full
1543 object. */
1544 set_value_pointed_to_offset (arg2, value_embedded_offset (arg1));
1545 return arg2;
1546 }
1547
1548 /* Return a reference value for the object for which ARG1 is the
1549 contents. */
1550
1551 struct value *
1552 value_ref (struct value *arg1)
1553 {
1554 struct value *arg2;
1555 struct type *type = check_typedef (value_type (arg1));
1556
1557 if (TYPE_CODE (type) == TYPE_CODE_REF)
1558 return arg1;
1559
1560 arg2 = value_addr (arg1);
1561 deprecated_set_value_type (arg2, lookup_reference_type (type));
1562 return arg2;
1563 }
1564
1565 /* Given a value of a pointer type, apply the C unary * operator to
1566 it. */
1567
1568 struct value *
1569 value_ind (struct value *arg1)
1570 {
1571 struct type *base_type;
1572 struct value *arg2;
1573
1574 arg1 = coerce_array (arg1);
1575
1576 base_type = check_typedef (value_type (arg1));
1577
1578 if (VALUE_LVAL (arg1) == lval_computed)
1579 {
1580 const struct lval_funcs *funcs = value_computed_funcs (arg1);
1581
1582 if (funcs->indirect)
1583 {
1584 struct value *result = funcs->indirect (arg1);
1585
1586 if (result)
1587 return result;
1588 }
1589 }
1590
1591 if (TYPE_CODE (base_type) == TYPE_CODE_PTR)
1592 {
1593 struct type *enc_type;
1594
1595 /* We may be pointing to something embedded in a larger object.
1596 Get the real type of the enclosing object. */
1597 enc_type = check_typedef (value_enclosing_type (arg1));
1598 enc_type = TYPE_TARGET_TYPE (enc_type);
1599
1600 if (TYPE_CODE (check_typedef (enc_type)) == TYPE_CODE_FUNC
1601 || TYPE_CODE (check_typedef (enc_type)) == TYPE_CODE_METHOD)
1602 /* For functions, go through find_function_addr, which knows
1603 how to handle function descriptors. */
1604 arg2 = value_at_lazy (enc_type,
1605 find_function_addr (arg1, NULL));
1606 else
1607 /* Retrieve the enclosing object pointed to. */
1608 arg2 = value_at_lazy (enc_type,
1609 (value_as_address (arg1)
1610 - value_pointed_to_offset (arg1)));
1611
1612 return readjust_indirect_value_type (arg2, enc_type, base_type, arg1);
1613 }
1614
1615 error (_("Attempt to take contents of a non-pointer value."));
1616 return 0; /* For lint -- never reached. */
1617 }
1618
1619 /* Create a value for an array by allocating space in GDB, copying the
1621 data into that space, and then setting up an array value.
1622
1623 The array bounds are set from LOWBOUND and HIGHBOUND, and the array
1624 is populated from the values passed in ELEMVEC.
1625
1626 The element type of the array is inherited from the type of the
1627 first element, and all elements must have the same size (though we
1628 don't currently enforce any restriction on their types). */
1629
1630 struct value *
1631 value_array (int lowbound, int highbound, struct value **elemvec)
1632 {
1633 int nelem;
1634 int idx;
1635 unsigned int typelength;
1636 struct value *val;
1637 struct type *arraytype;
1638
1639 /* Validate that the bounds are reasonable and that each of the
1640 elements have the same size. */
1641
1642 nelem = highbound - lowbound + 1;
1643 if (nelem <= 0)
1644 {
1645 error (_("bad array bounds (%d, %d)"), lowbound, highbound);
1646 }
1647 typelength = TYPE_LENGTH (value_enclosing_type (elemvec[0]));
1648 for (idx = 1; idx < nelem; idx++)
1649 {
1650 if (TYPE_LENGTH (value_enclosing_type (elemvec[idx])) != typelength)
1651 {
1652 error (_("array elements must all be the same size"));
1653 }
1654 }
1655
1656 arraytype = lookup_array_range_type (value_enclosing_type (elemvec[0]),
1657 lowbound, highbound);
1658
1659 if (!current_language->c_style_arrays)
1660 {
1661 val = allocate_value (arraytype);
1662 for (idx = 0; idx < nelem; idx++)
1663 value_contents_copy (val, idx * typelength, elemvec[idx], 0,
1664 typelength);
1665 return val;
1666 }
1667
1668 /* Allocate space to store the array, and then initialize it by
1669 copying in each element. */
1670
1671 val = allocate_value (arraytype);
1672 for (idx = 0; idx < nelem; idx++)
1673 value_contents_copy (val, idx * typelength, elemvec[idx], 0, typelength);
1674 return val;
1675 }
1676
1677 struct value *
1678 value_cstring (char *ptr, ssize_t len, struct type *char_type)
1679 {
1680 struct value *val;
1681 int lowbound = current_language->string_lower_bound;
1682 ssize_t highbound = len / TYPE_LENGTH (char_type);
1683 struct type *stringtype
1684 = lookup_array_range_type (char_type, lowbound, highbound + lowbound - 1);
1685
1686 val = allocate_value (stringtype);
1687 memcpy (value_contents_raw (val), ptr, len);
1688 return val;
1689 }
1690
1691 /* Create a value for a string constant by allocating space in the
1692 inferior, copying the data into that space, and returning the
1693 address with type TYPE_CODE_STRING. PTR points to the string
1694 constant data; LEN is number of characters.
1695
1696 Note that string types are like array of char types with a lower
1697 bound of zero and an upper bound of LEN - 1. Also note that the
1698 string may contain embedded null bytes. */
1699
1700 struct value *
1701 value_string (char *ptr, ssize_t len, struct type *char_type)
1702 {
1703 struct value *val;
1704 int lowbound = current_language->string_lower_bound;
1705 ssize_t highbound = len / TYPE_LENGTH (char_type);
1706 struct type *stringtype
1707 = lookup_string_range_type (char_type, lowbound, highbound + lowbound - 1);
1708
1709 val = allocate_value (stringtype);
1710 memcpy (value_contents_raw (val), ptr, len);
1711 return val;
1712 }
1713
1714
1715 /* See if we can pass arguments in T2 to a function which takes
1717 arguments of types T1. T1 is a list of NARGS arguments, and T2 is
1718 a NULL-terminated vector. If some arguments need coercion of some
1719 sort, then the coerced values are written into T2. Return value is
1720 0 if the arguments could be matched, or the position at which they
1721 differ if not.
1722
1723 STATICP is nonzero if the T1 argument list came from a static
1724 member function. T2 will still include the ``this'' pointer, but
1725 it will be skipped.
1726
1727 For non-static member functions, we ignore the first argument,
1728 which is the type of the instance variable. This is because we
1729 want to handle calls with objects from derived classes. This is
1730 not entirely correct: we should actually check to make sure that a
1731 requested operation is type secure, shouldn't we? FIXME. */
1732
1733 static int
1734 typecmp (int staticp, int varargs, int nargs,
1735 struct field t1[], struct value *t2[])
1736 {
1737 int i;
1738
1739 if (t2 == 0)
1740 internal_error (__FILE__, __LINE__,
1741 _("typecmp: no argument list"));
1742
1743 /* Skip ``this'' argument if applicable. T2 will always include
1744 THIS. */
1745 if (staticp)
1746 t2 ++;
1747
1748 for (i = 0;
1749 (i < nargs) && TYPE_CODE (t1[i].type) != TYPE_CODE_VOID;
1750 i++)
1751 {
1752 struct type *tt1, *tt2;
1753
1754 if (!t2[i])
1755 return i + 1;
1756
1757 tt1 = check_typedef (t1[i].type);
1758 tt2 = check_typedef (value_type (t2[i]));
1759
1760 if (TYPE_CODE (tt1) == TYPE_CODE_REF
1761 /* We should be doing hairy argument matching, as below. */
1762 && (TYPE_CODE (check_typedef (TYPE_TARGET_TYPE (tt1)))
1763 == TYPE_CODE (tt2)))
1764 {
1765 if (TYPE_CODE (tt2) == TYPE_CODE_ARRAY)
1766 t2[i] = value_coerce_array (t2[i]);
1767 else
1768 t2[i] = value_ref (t2[i]);
1769 continue;
1770 }
1771
1772 /* djb - 20000715 - Until the new type structure is in the
1773 place, and we can attempt things like implicit conversions,
1774 we need to do this so you can take something like a map<const
1775 char *>, and properly access map["hello"], because the
1776 argument to [] will be a reference to a pointer to a char,
1777 and the argument will be a pointer to a char. */
1778 while (TYPE_CODE(tt1) == TYPE_CODE_REF
1779 || TYPE_CODE (tt1) == TYPE_CODE_PTR)
1780 {
1781 tt1 = check_typedef( TYPE_TARGET_TYPE(tt1) );
1782 }
1783 while (TYPE_CODE(tt2) == TYPE_CODE_ARRAY
1784 || TYPE_CODE(tt2) == TYPE_CODE_PTR
1785 || TYPE_CODE(tt2) == TYPE_CODE_REF)
1786 {
1787 tt2 = check_typedef (TYPE_TARGET_TYPE(tt2));
1788 }
1789 if (TYPE_CODE (tt1) == TYPE_CODE (tt2))
1790 continue;
1791 /* Array to pointer is a `trivial conversion' according to the
1792 ARM. */
1793
1794 /* We should be doing much hairier argument matching (see
1795 section 13.2 of the ARM), but as a quick kludge, just check
1796 for the same type code. */
1797 if (TYPE_CODE (t1[i].type) != TYPE_CODE (value_type (t2[i])))
1798 return i + 1;
1799 }
1800 if (varargs || t2[i] == NULL)
1801 return 0;
1802 return i + 1;
1803 }
1804
1805 /* Helper class for do_search_struct_field that updates *RESULT_PTR
1806 and *LAST_BOFFSET, and possibly throws an exception if the field
1807 search has yielded ambiguous results. */
1808
1809 static void
1810 update_search_result (struct value **result_ptr, struct value *v,
1811 int *last_boffset, int boffset,
1812 const char *name, struct type *type)
1813 {
1814 if (v != NULL)
1815 {
1816 if (*result_ptr != NULL
1817 /* The result is not ambiguous if all the classes that are
1818 found occupy the same space. */
1819 && *last_boffset != boffset)
1820 error (_("base class '%s' is ambiguous in type '%s'"),
1821 name, TYPE_SAFE_NAME (type));
1822 *result_ptr = v;
1823 *last_boffset = boffset;
1824 }
1825 }
1826
1827 /* A helper for search_struct_field. This does all the work; most
1828 arguments are as passed to search_struct_field. The result is
1829 stored in *RESULT_PTR, which must be initialized to NULL.
1830 OUTERMOST_TYPE is the type of the initial type passed to
1831 search_struct_field; this is used for error reporting when the
1832 lookup is ambiguous. */
1833
1834 static void
1835 do_search_struct_field (const char *name, struct value *arg1, int offset,
1836 struct type *type, int looking_for_baseclass,
1837 struct value **result_ptr,
1838 int *last_boffset,
1839 struct type *outermost_type)
1840 {
1841 int i;
1842 int nbases;
1843
1844 CHECK_TYPEDEF (type);
1845 nbases = TYPE_N_BASECLASSES (type);
1846
1847 if (!looking_for_baseclass)
1848 for (i = TYPE_NFIELDS (type) - 1; i >= nbases; i--)
1849 {
1850 const char *t_field_name = TYPE_FIELD_NAME (type, i);
1851
1852 if (t_field_name && (strcmp_iw (t_field_name, name) == 0))
1853 {
1854 struct value *v;
1855
1856 if (field_is_static (&TYPE_FIELD (type, i)))
1857 v = value_static_field (type, i);
1858 else
1859 v = value_primitive_field (arg1, offset, i, type);
1860 *result_ptr = v;
1861 return;
1862 }
1863
1864 if (t_field_name
1865 && (t_field_name[0] == '\0'
1866 || (TYPE_CODE (type) == TYPE_CODE_UNION
1867 && (strcmp_iw (t_field_name, "else") == 0))))
1868 {
1869 struct type *field_type = TYPE_FIELD_TYPE (type, i);
1870
1871 if (TYPE_CODE (field_type) == TYPE_CODE_UNION
1872 || TYPE_CODE (field_type) == TYPE_CODE_STRUCT)
1873 {
1874 /* Look for a match through the fields of an anonymous
1875 union, or anonymous struct. C++ provides anonymous
1876 unions.
1877
1878 In the GNU Chill (now deleted from GDB)
1879 implementation of variant record types, each
1880 <alternative field> has an (anonymous) union type,
1881 each member of the union represents a <variant
1882 alternative>. Each <variant alternative> is
1883 represented as a struct, with a member for each
1884 <variant field>. */
1885
1886 struct value *v = NULL;
1887 int new_offset = offset;
1888
1889 /* This is pretty gross. In G++, the offset in an
1890 anonymous union is relative to the beginning of the
1891 enclosing struct. In the GNU Chill (now deleted
1892 from GDB) implementation of variant records, the
1893 bitpos is zero in an anonymous union field, so we
1894 have to add the offset of the union here. */
1895 if (TYPE_CODE (field_type) == TYPE_CODE_STRUCT
1896 || (TYPE_NFIELDS (field_type) > 0
1897 && TYPE_FIELD_BITPOS (field_type, 0) == 0))
1898 new_offset += TYPE_FIELD_BITPOS (type, i) / 8;
1899
1900 do_search_struct_field (name, arg1, new_offset,
1901 field_type,
1902 looking_for_baseclass, &v,
1903 last_boffset,
1904 outermost_type);
1905 if (v)
1906 {
1907 *result_ptr = v;
1908 return;
1909 }
1910 }
1911 }
1912 }
1913
1914 for (i = 0; i < nbases; i++)
1915 {
1916 struct value *v = NULL;
1917 struct type *basetype = check_typedef (TYPE_BASECLASS (type, i));
1918 /* If we are looking for baseclasses, this is what we get when
1919 we hit them. But it could happen that the base part's member
1920 name is not yet filled in. */
1921 int found_baseclass = (looking_for_baseclass
1922 && TYPE_BASECLASS_NAME (type, i) != NULL
1923 && (strcmp_iw (name,
1924 TYPE_BASECLASS_NAME (type,
1925 i)) == 0));
1926 int boffset = value_embedded_offset (arg1) + offset;
1927
1928 if (BASETYPE_VIA_VIRTUAL (type, i))
1929 {
1930 struct value *v2;
1931
1932 boffset = baseclass_offset (type, i,
1933 value_contents_for_printing (arg1),
1934 value_embedded_offset (arg1) + offset,
1935 value_address (arg1),
1936 arg1);
1937
1938 /* The virtual base class pointer might have been clobbered
1939 by the user program. Make sure that it still points to a
1940 valid memory location. */
1941
1942 boffset += value_embedded_offset (arg1) + offset;
1943 if (boffset < 0
1944 || boffset >= TYPE_LENGTH (value_enclosing_type (arg1)))
1945 {
1946 CORE_ADDR base_addr;
1947
1948 base_addr = value_address (arg1) + boffset;
1949 v2 = value_at_lazy (basetype, base_addr);
1950 if (target_read_memory (base_addr,
1951 value_contents_raw (v2),
1952 TYPE_LENGTH (value_type (v2))) != 0)
1953 error (_("virtual baseclass botch"));
1954 }
1955 else
1956 {
1957 v2 = value_copy (arg1);
1958 deprecated_set_value_type (v2, basetype);
1959 set_value_embedded_offset (v2, boffset);
1960 }
1961
1962 if (found_baseclass)
1963 v = v2;
1964 else
1965 {
1966 do_search_struct_field (name, v2, 0,
1967 TYPE_BASECLASS (type, i),
1968 looking_for_baseclass,
1969 result_ptr, last_boffset,
1970 outermost_type);
1971 }
1972 }
1973 else if (found_baseclass)
1974 v = value_primitive_field (arg1, offset, i, type);
1975 else
1976 {
1977 do_search_struct_field (name, arg1,
1978 offset + TYPE_BASECLASS_BITPOS (type,
1979 i) / 8,
1980 basetype, looking_for_baseclass,
1981 result_ptr, last_boffset,
1982 outermost_type);
1983 }
1984
1985 update_search_result (result_ptr, v, last_boffset,
1986 boffset, name, outermost_type);
1987 }
1988 }
1989
1990 /* Helper function used by value_struct_elt to recurse through
1991 baseclasses. Look for a field NAME in ARG1. Adjust the address of
1992 ARG1 by OFFSET bytes, and search in it assuming it has (class) type
1993 TYPE. If found, return value, else return NULL.
1994
1995 If LOOKING_FOR_BASECLASS, then instead of looking for struct
1996 fields, look for a baseclass named NAME. */
1997
1998 static struct value *
1999 search_struct_field (const char *name, struct value *arg1, int offset,
2000 struct type *type, int looking_for_baseclass)
2001 {
2002 struct value *result = NULL;
2003 int boffset = 0;
2004
2005 do_search_struct_field (name, arg1, offset, type, looking_for_baseclass,
2006 &result, &boffset, type);
2007 return result;
2008 }
2009
2010 /* Helper function used by value_struct_elt to recurse through
2011 baseclasses. Look for a field NAME in ARG1. Adjust the address of
2012 ARG1 by OFFSET bytes, and search in it assuming it has (class) type
2013 TYPE.
2014
2015 If found, return value, else if name matched and args not return
2016 (value) -1, else return NULL. */
2017
2018 static struct value *
2019 search_struct_method (const char *name, struct value **arg1p,
2020 struct value **args, int offset,
2021 int *static_memfuncp, struct type *type)
2022 {
2023 int i;
2024 struct value *v;
2025 int name_matched = 0;
2026 char dem_opname[64];
2027
2028 CHECK_TYPEDEF (type);
2029 for (i = TYPE_NFN_FIELDS (type) - 1; i >= 0; i--)
2030 {
2031 const char *t_field_name = TYPE_FN_FIELDLIST_NAME (type, i);
2032
2033 /* FIXME! May need to check for ARM demangling here. */
2034 if (strncmp (t_field_name, "__", 2) == 0 ||
2035 strncmp (t_field_name, "op", 2) == 0 ||
2036 strncmp (t_field_name, "type", 4) == 0)
2037 {
2038 if (cplus_demangle_opname (t_field_name, dem_opname, DMGL_ANSI))
2039 t_field_name = dem_opname;
2040 else if (cplus_demangle_opname (t_field_name, dem_opname, 0))
2041 t_field_name = dem_opname;
2042 }
2043 if (t_field_name && (strcmp_iw (t_field_name, name) == 0))
2044 {
2045 int j = TYPE_FN_FIELDLIST_LENGTH (type, i) - 1;
2046 struct fn_field *f = TYPE_FN_FIELDLIST1 (type, i);
2047
2048 name_matched = 1;
2049 check_stub_method_group (type, i);
2050 if (j > 0 && args == 0)
2051 error (_("cannot resolve overloaded method "
2052 "`%s': no arguments supplied"), name);
2053 else if (j == 0 && args == 0)
2054 {
2055 v = value_fn_field (arg1p, f, j, type, offset);
2056 if (v != NULL)
2057 return v;
2058 }
2059 else
2060 while (j >= 0)
2061 {
2062 if (!typecmp (TYPE_FN_FIELD_STATIC_P (f, j),
2063 TYPE_VARARGS (TYPE_FN_FIELD_TYPE (f, j)),
2064 TYPE_NFIELDS (TYPE_FN_FIELD_TYPE (f, j)),
2065 TYPE_FN_FIELD_ARGS (f, j), args))
2066 {
2067 if (TYPE_FN_FIELD_VIRTUAL_P (f, j))
2068 return value_virtual_fn_field (arg1p, f, j,
2069 type, offset);
2070 if (TYPE_FN_FIELD_STATIC_P (f, j)
2071 && static_memfuncp)
2072 *static_memfuncp = 1;
2073 v = value_fn_field (arg1p, f, j, type, offset);
2074 if (v != NULL)
2075 return v;
2076 }
2077 j--;
2078 }
2079 }
2080 }
2081
2082 for (i = TYPE_N_BASECLASSES (type) - 1; i >= 0; i--)
2083 {
2084 int base_offset;
2085 int this_offset;
2086
2087 if (BASETYPE_VIA_VIRTUAL (type, i))
2088 {
2089 struct type *baseclass = check_typedef (TYPE_BASECLASS (type, i));
2090 struct value *base_val;
2091 const gdb_byte *base_valaddr;
2092
2093 /* The virtual base class pointer might have been
2094 clobbered by the user program. Make sure that it
2095 still points to a valid memory location. */
2096
2097 if (offset < 0 || offset >= TYPE_LENGTH (type))
2098 {
2099 gdb_byte *tmp;
2100 struct cleanup *back_to;
2101 CORE_ADDR address;
2102
2103 tmp = xmalloc (TYPE_LENGTH (baseclass));
2104 back_to = make_cleanup (xfree, tmp);
2105 address = value_address (*arg1p);
2106
2107 if (target_read_memory (address + offset,
2108 tmp, TYPE_LENGTH (baseclass)) != 0)
2109 error (_("virtual baseclass botch"));
2110
2111 base_val = value_from_contents_and_address (baseclass,
2112 tmp,
2113 address + offset);
2114 base_valaddr = value_contents_for_printing (base_val);
2115 this_offset = 0;
2116 do_cleanups (back_to);
2117 }
2118 else
2119 {
2120 base_val = *arg1p;
2121 base_valaddr = value_contents_for_printing (*arg1p);
2122 this_offset = offset;
2123 }
2124
2125 base_offset = baseclass_offset (type, i, base_valaddr,
2126 this_offset, value_address (base_val),
2127 base_val);
2128 }
2129 else
2130 {
2131 base_offset = TYPE_BASECLASS_BITPOS (type, i) / 8;
2132 }
2133 v = search_struct_method (name, arg1p, args, base_offset + offset,
2134 static_memfuncp, TYPE_BASECLASS (type, i));
2135 if (v == (struct value *) - 1)
2136 {
2137 name_matched = 1;
2138 }
2139 else if (v)
2140 {
2141 /* FIXME-bothner: Why is this commented out? Why is it here? */
2142 /* *arg1p = arg1_tmp; */
2143 return v;
2144 }
2145 }
2146 if (name_matched)
2147 return (struct value *) - 1;
2148 else
2149 return NULL;
2150 }
2151
2152 /* Given *ARGP, a value of type (pointer to a)* structure/union,
2153 extract the component named NAME from the ultimate target
2154 structure/union and return it as a value with its appropriate type.
2155 ERR is used in the error message if *ARGP's type is wrong.
2156
2157 C++: ARGS is a list of argument types to aid in the selection of
2158 an appropriate method. Also, handle derived types.
2159
2160 STATIC_MEMFUNCP, if non-NULL, points to a caller-supplied location
2161 where the truthvalue of whether the function that was resolved was
2162 a static member function or not is stored.
2163
2164 ERR is an error message to be printed in case the field is not
2165 found. */
2166
2167 struct value *
2168 value_struct_elt (struct value **argp, struct value **args,
2169 const char *name, int *static_memfuncp, const char *err)
2170 {
2171 struct type *t;
2172 struct value *v;
2173
2174 *argp = coerce_array (*argp);
2175
2176 t = check_typedef (value_type (*argp));
2177
2178 /* Follow pointers until we get to a non-pointer. */
2179
2180 while (TYPE_CODE (t) == TYPE_CODE_PTR || TYPE_CODE (t) == TYPE_CODE_REF)
2181 {
2182 *argp = value_ind (*argp);
2183 /* Don't coerce fn pointer to fn and then back again! */
2184 if (TYPE_CODE (check_typedef (value_type (*argp))) != TYPE_CODE_FUNC)
2185 *argp = coerce_array (*argp);
2186 t = check_typedef (value_type (*argp));
2187 }
2188
2189 if (TYPE_CODE (t) != TYPE_CODE_STRUCT
2190 && TYPE_CODE (t) != TYPE_CODE_UNION)
2191 error (_("Attempt to extract a component of a value that is not a %s."),
2192 err);
2193
2194 /* Assume it's not, unless we see that it is. */
2195 if (static_memfuncp)
2196 *static_memfuncp = 0;
2197
2198 if (!args)
2199 {
2200 /* if there are no arguments ...do this... */
2201
2202 /* Try as a field first, because if we succeed, there is less
2203 work to be done. */
2204 v = search_struct_field (name, *argp, 0, t, 0);
2205 if (v)
2206 return v;
2207
2208 /* C++: If it was not found as a data field, then try to
2209 return it as a pointer to a method. */
2210 v = search_struct_method (name, argp, args, 0,
2211 static_memfuncp, t);
2212
2213 if (v == (struct value *) - 1)
2214 error (_("Cannot take address of method %s."), name);
2215 else if (v == 0)
2216 {
2217 if (TYPE_NFN_FIELDS (t))
2218 error (_("There is no member or method named %s."), name);
2219 else
2220 error (_("There is no member named %s."), name);
2221 }
2222 return v;
2223 }
2224
2225 v = search_struct_method (name, argp, args, 0,
2226 static_memfuncp, t);
2227
2228 if (v == (struct value *) - 1)
2229 {
2230 error (_("One of the arguments you tried to pass to %s could not "
2231 "be converted to what the function wants."), name);
2232 }
2233 else if (v == 0)
2234 {
2235 /* See if user tried to invoke data as function. If so, hand it
2236 back. If it's not callable (i.e., a pointer to function),
2237 gdb should give an error. */
2238 v = search_struct_field (name, *argp, 0, t, 0);
2239 /* If we found an ordinary field, then it is not a method call.
2240 So, treat it as if it were a static member function. */
2241 if (v && static_memfuncp)
2242 *static_memfuncp = 1;
2243 }
2244
2245 if (!v)
2246 throw_error (NOT_FOUND_ERROR,
2247 _("Structure has no component named %s."), name);
2248 return v;
2249 }
2250
2251 /* Given *ARGP, a value of type structure or union, or a pointer/reference
2252 to a structure or union, extract and return its component (field) of
2253 type FTYPE at the specified BITPOS.
2254 Throw an exception on error. */
2255
2256 struct value *
2257 value_struct_elt_bitpos (struct value **argp, int bitpos, struct type *ftype,
2258 const char *err)
2259 {
2260 struct type *t;
2261 struct value *v;
2262 int i;
2263 int nbases;
2264
2265 *argp = coerce_array (*argp);
2266
2267 t = check_typedef (value_type (*argp));
2268
2269 while (TYPE_CODE (t) == TYPE_CODE_PTR || TYPE_CODE (t) == TYPE_CODE_REF)
2270 {
2271 *argp = value_ind (*argp);
2272 if (TYPE_CODE (check_typedef (value_type (*argp))) != TYPE_CODE_FUNC)
2273 *argp = coerce_array (*argp);
2274 t = check_typedef (value_type (*argp));
2275 }
2276
2277 if (TYPE_CODE (t) != TYPE_CODE_STRUCT
2278 && TYPE_CODE (t) != TYPE_CODE_UNION)
2279 error (_("Attempt to extract a component of a value that is not a %s."),
2280 err);
2281
2282 for (i = TYPE_N_BASECLASSES (t); i < TYPE_NFIELDS (t); i++)
2283 {
2284 if (!field_is_static (&TYPE_FIELD (t, i))
2285 && bitpos == TYPE_FIELD_BITPOS (t, i)
2286 && types_equal (ftype, TYPE_FIELD_TYPE (t, i)))
2287 return value_primitive_field (*argp, 0, i, t);
2288 }
2289
2290 error (_("No field with matching bitpos and type."));
2291
2292 /* Never hit. */
2293 return NULL;
2294 }
2295
2296 /* Search through the methods of an object (and its bases) to find a
2297 specified method. Return the pointer to the fn_field list of
2298 overloaded instances.
2299
2300 Helper function for value_find_oload_list.
2301 ARGP is a pointer to a pointer to a value (the object).
2302 METHOD is a string containing the method name.
2303 OFFSET is the offset within the value.
2304 TYPE is the assumed type of the object.
2305 NUM_FNS is the number of overloaded instances.
2306 BASETYPE is set to the actual type of the subobject where the
2307 method is found.
2308 BOFFSET is the offset of the base subobject where the method is found. */
2309
2310 static struct fn_field *
2311 find_method_list (struct value **argp, const char *method,
2312 int offset, struct type *type, int *num_fns,
2313 struct type **basetype, int *boffset)
2314 {
2315 int i;
2316 struct fn_field *f;
2317 CHECK_TYPEDEF (type);
2318
2319 *num_fns = 0;
2320
2321 /* First check in object itself. */
2322 for (i = TYPE_NFN_FIELDS (type) - 1; i >= 0; i--)
2323 {
2324 /* pai: FIXME What about operators and type conversions? */
2325 const char *fn_field_name = TYPE_FN_FIELDLIST_NAME (type, i);
2326
2327 if (fn_field_name && (strcmp_iw (fn_field_name, method) == 0))
2328 {
2329 int len = TYPE_FN_FIELDLIST_LENGTH (type, i);
2330 struct fn_field *f = TYPE_FN_FIELDLIST1 (type, i);
2331
2332 *num_fns = len;
2333 *basetype = type;
2334 *boffset = offset;
2335
2336 /* Resolve any stub methods. */
2337 check_stub_method_group (type, i);
2338
2339 return f;
2340 }
2341 }
2342
2343 /* Not found in object, check in base subobjects. */
2344 for (i = TYPE_N_BASECLASSES (type) - 1; i >= 0; i--)
2345 {
2346 int base_offset;
2347
2348 if (BASETYPE_VIA_VIRTUAL (type, i))
2349 {
2350 base_offset = baseclass_offset (type, i,
2351 value_contents_for_printing (*argp),
2352 value_offset (*argp) + offset,
2353 value_address (*argp), *argp);
2354 }
2355 else /* Non-virtual base, simply use bit position from debug
2356 info. */
2357 {
2358 base_offset = TYPE_BASECLASS_BITPOS (type, i) / 8;
2359 }
2360 f = find_method_list (argp, method, base_offset + offset,
2361 TYPE_BASECLASS (type, i), num_fns,
2362 basetype, boffset);
2363 if (f)
2364 return f;
2365 }
2366 return NULL;
2367 }
2368
2369 /* Return the list of overloaded methods of a specified name.
2370
2371 ARGP is a pointer to a pointer to a value (the object).
2372 METHOD is the method name.
2373 OFFSET is the offset within the value contents.
2374 NUM_FNS is the number of overloaded instances.
2375 BASETYPE is set to the type of the base subobject that defines the
2376 method.
2377 BOFFSET is the offset of the base subobject which defines the method. */
2378
2379 static struct fn_field *
2380 value_find_oload_method_list (struct value **argp, const char *method,
2381 int offset, int *num_fns,
2382 struct type **basetype, int *boffset)
2383 {
2384 struct type *t;
2385
2386 t = check_typedef (value_type (*argp));
2387
2388 /* Code snarfed from value_struct_elt. */
2389 while (TYPE_CODE (t) == TYPE_CODE_PTR || TYPE_CODE (t) == TYPE_CODE_REF)
2390 {
2391 *argp = value_ind (*argp);
2392 /* Don't coerce fn pointer to fn and then back again! */
2393 if (TYPE_CODE (check_typedef (value_type (*argp))) != TYPE_CODE_FUNC)
2394 *argp = coerce_array (*argp);
2395 t = check_typedef (value_type (*argp));
2396 }
2397
2398 if (TYPE_CODE (t) != TYPE_CODE_STRUCT
2399 && TYPE_CODE (t) != TYPE_CODE_UNION)
2400 error (_("Attempt to extract a component of a "
2401 "value that is not a struct or union"));
2402
2403 return find_method_list (argp, method, 0, t, num_fns,
2404 basetype, boffset);
2405 }
2406
2407 /* Given an array of arguments (ARGS) (which includes an
2408 entry for "this" in the case of C++ methods), the number of
2409 arguments NARGS, the NAME of a function, and whether it's a method or
2410 not (METHOD), find the best function that matches on the argument types
2411 according to the overload resolution rules.
2412
2413 METHOD can be one of three values:
2414 NON_METHOD for non-member functions.
2415 METHOD: for member functions.
2416 BOTH: used for overload resolution of operators where the
2417 candidates are expected to be either member or non member
2418 functions. In this case the first argument ARGTYPES
2419 (representing 'this') is expected to be a reference to the
2420 target object, and will be dereferenced when attempting the
2421 non-member search.
2422
2423 In the case of class methods, the parameter OBJ is an object value
2424 in which to search for overloaded methods.
2425
2426 In the case of non-method functions, the parameter FSYM is a symbol
2427 corresponding to one of the overloaded functions.
2428
2429 Return value is an integer: 0 -> good match, 10 -> debugger applied
2430 non-standard coercions, 100 -> incompatible.
2431
2432 If a method is being searched for, VALP will hold the value.
2433 If a non-method is being searched for, SYMP will hold the symbol
2434 for it.
2435
2436 If a method is being searched for, and it is a static method,
2437 then STATICP will point to a non-zero value.
2438
2439 If NO_ADL argument dependent lookup is disabled. This is used to prevent
2440 ADL overload candidates when performing overload resolution for a fully
2441 qualified name.
2442
2443 Note: This function does *not* check the value of
2444 overload_resolution. Caller must check it to see whether overload
2445 resolution is permitted. */
2446
2447 int
2448 find_overload_match (struct value **args, int nargs,
2449 const char *name, enum oload_search_type method,
2450 struct value **objp, struct symbol *fsym,
2451 struct value **valp, struct symbol **symp,
2452 int *staticp, const int no_adl)
2453 {
2454 struct value *obj = (objp ? *objp : NULL);
2455 struct type *obj_type = obj ? value_type (obj) : NULL;
2456 /* Index of best overloaded function. */
2457 int func_oload_champ = -1;
2458 int method_oload_champ = -1;
2459
2460 /* The measure for the current best match. */
2461 struct badness_vector *method_badness = NULL;
2462 struct badness_vector *func_badness = NULL;
2463
2464 struct value *temp = obj;
2465 /* For methods, the list of overloaded methods. */
2466 struct fn_field *fns_ptr = NULL;
2467 /* For non-methods, the list of overloaded function symbols. */
2468 struct symbol **oload_syms = NULL;
2469 /* Number of overloaded instances being considered. */
2470 int num_fns = 0;
2471 struct type *basetype = NULL;
2472 int boffset;
2473
2474 struct cleanup *all_cleanups = make_cleanup (null_cleanup, NULL);
2475
2476 const char *obj_type_name = NULL;
2477 const char *func_name = NULL;
2478 enum oload_classification match_quality;
2479 enum oload_classification method_match_quality = INCOMPATIBLE;
2480 enum oload_classification func_match_quality = INCOMPATIBLE;
2481
2482 /* Get the list of overloaded methods or functions. */
2483 if (method == METHOD || method == BOTH)
2484 {
2485 gdb_assert (obj);
2486
2487 /* OBJ may be a pointer value rather than the object itself. */
2488 obj = coerce_ref (obj);
2489 while (TYPE_CODE (check_typedef (value_type (obj))) == TYPE_CODE_PTR)
2490 obj = coerce_ref (value_ind (obj));
2491 obj_type_name = TYPE_NAME (value_type (obj));
2492
2493 /* First check whether this is a data member, e.g. a pointer to
2494 a function. */
2495 if (TYPE_CODE (check_typedef (value_type (obj))) == TYPE_CODE_STRUCT)
2496 {
2497 *valp = search_struct_field (name, obj, 0,
2498 check_typedef (value_type (obj)), 0);
2499 if (*valp)
2500 {
2501 *staticp = 1;
2502 do_cleanups (all_cleanups);
2503 return 0;
2504 }
2505 }
2506
2507 /* Retrieve the list of methods with the name NAME. */
2508 fns_ptr = value_find_oload_method_list (&temp, name,
2509 0, &num_fns,
2510 &basetype, &boffset);
2511 /* If this is a method only search, and no methods were found
2512 the search has faild. */
2513 if (method == METHOD && (!fns_ptr || !num_fns))
2514 error (_("Couldn't find method %s%s%s"),
2515 obj_type_name,
2516 (obj_type_name && *obj_type_name) ? "::" : "",
2517 name);
2518 /* If we are dealing with stub method types, they should have
2519 been resolved by find_method_list via
2520 value_find_oload_method_list above. */
2521 if (fns_ptr)
2522 {
2523 gdb_assert (TYPE_DOMAIN_TYPE (fns_ptr[0].type) != NULL);
2524 method_oload_champ = find_oload_champ (args, nargs, method,
2525 num_fns, fns_ptr,
2526 oload_syms, &method_badness);
2527
2528 method_match_quality =
2529 classify_oload_match (method_badness, nargs,
2530 oload_method_static (method, fns_ptr,
2531 method_oload_champ));
2532
2533 make_cleanup (xfree, method_badness);
2534 }
2535
2536 }
2537
2538 if (method == NON_METHOD || method == BOTH)
2539 {
2540 const char *qualified_name = NULL;
2541
2542 /* If the overload match is being search for both as a method
2543 and non member function, the first argument must now be
2544 dereferenced. */
2545 if (method == BOTH)
2546 args[0] = value_ind (args[0]);
2547
2548 if (fsym)
2549 {
2550 qualified_name = SYMBOL_NATURAL_NAME (fsym);
2551
2552 /* If we have a function with a C++ name, try to extract just
2553 the function part. Do not try this for non-functions (e.g.
2554 function pointers). */
2555 if (qualified_name
2556 && TYPE_CODE (check_typedef (SYMBOL_TYPE (fsym)))
2557 == TYPE_CODE_FUNC)
2558 {
2559 char *temp;
2560
2561 temp = cp_func_name (qualified_name);
2562
2563 /* If cp_func_name did not remove anything, the name of the
2564 symbol did not include scope or argument types - it was
2565 probably a C-style function. */
2566 if (temp)
2567 {
2568 make_cleanup (xfree, temp);
2569 if (strcmp (temp, qualified_name) == 0)
2570 func_name = NULL;
2571 else
2572 func_name = temp;
2573 }
2574 }
2575 }
2576 else
2577 {
2578 func_name = name;
2579 qualified_name = name;
2580 }
2581
2582 /* If there was no C++ name, this must be a C-style function or
2583 not a function at all. Just return the same symbol. Do the
2584 same if cp_func_name fails for some reason. */
2585 if (func_name == NULL)
2586 {
2587 *symp = fsym;
2588 do_cleanups (all_cleanups);
2589 return 0;
2590 }
2591
2592 func_oload_champ = find_oload_champ_namespace (args, nargs,
2593 func_name,
2594 qualified_name,
2595 &oload_syms,
2596 &func_badness,
2597 no_adl);
2598
2599 if (func_oload_champ >= 0)
2600 func_match_quality = classify_oload_match (func_badness, nargs, 0);
2601
2602 make_cleanup (xfree, oload_syms);
2603 make_cleanup (xfree, func_badness);
2604 }
2605
2606 /* Did we find a match ? */
2607 if (method_oload_champ == -1 && func_oload_champ == -1)
2608 throw_error (NOT_FOUND_ERROR,
2609 _("No symbol \"%s\" in current context."),
2610 name);
2611
2612 /* If we have found both a method match and a function
2613 match, find out which one is better, and calculate match
2614 quality. */
2615 if (method_oload_champ >= 0 && func_oload_champ >= 0)
2616 {
2617 switch (compare_badness (func_badness, method_badness))
2618 {
2619 case 0: /* Top two contenders are equally good. */
2620 /* FIXME: GDB does not support the general ambiguous case.
2621 All candidates should be collected and presented the
2622 user. */
2623 error (_("Ambiguous overload resolution"));
2624 break;
2625 case 1: /* Incomparable top contenders. */
2626 /* This is an error incompatible candidates
2627 should not have been proposed. */
2628 error (_("Internal error: incompatible "
2629 "overload candidates proposed"));
2630 break;
2631 case 2: /* Function champion. */
2632 method_oload_champ = -1;
2633 match_quality = func_match_quality;
2634 break;
2635 case 3: /* Method champion. */
2636 func_oload_champ = -1;
2637 match_quality = method_match_quality;
2638 break;
2639 default:
2640 error (_("Internal error: unexpected overload comparison result"));
2641 break;
2642 }
2643 }
2644 else
2645 {
2646 /* We have either a method match or a function match. */
2647 if (method_oload_champ >= 0)
2648 match_quality = method_match_quality;
2649 else
2650 match_quality = func_match_quality;
2651 }
2652
2653 if (match_quality == INCOMPATIBLE)
2654 {
2655 if (method == METHOD)
2656 error (_("Cannot resolve method %s%s%s to any overloaded instance"),
2657 obj_type_name,
2658 (obj_type_name && *obj_type_name) ? "::" : "",
2659 name);
2660 else
2661 error (_("Cannot resolve function %s to any overloaded instance"),
2662 func_name);
2663 }
2664 else if (match_quality == NON_STANDARD)
2665 {
2666 if (method == METHOD)
2667 warning (_("Using non-standard conversion to match "
2668 "method %s%s%s to supplied arguments"),
2669 obj_type_name,
2670 (obj_type_name && *obj_type_name) ? "::" : "",
2671 name);
2672 else
2673 warning (_("Using non-standard conversion to match "
2674 "function %s to supplied arguments"),
2675 func_name);
2676 }
2677
2678 if (staticp != NULL)
2679 *staticp = oload_method_static (method, fns_ptr, method_oload_champ);
2680
2681 if (method_oload_champ >= 0)
2682 {
2683 if (TYPE_FN_FIELD_VIRTUAL_P (fns_ptr, method_oload_champ))
2684 *valp = value_virtual_fn_field (&temp, fns_ptr, method_oload_champ,
2685 basetype, boffset);
2686 else
2687 *valp = value_fn_field (&temp, fns_ptr, method_oload_champ,
2688 basetype, boffset);
2689 }
2690 else
2691 *symp = oload_syms[func_oload_champ];
2692
2693 if (objp)
2694 {
2695 struct type *temp_type = check_typedef (value_type (temp));
2696 struct type *objtype = check_typedef (obj_type);
2697
2698 if (TYPE_CODE (temp_type) != TYPE_CODE_PTR
2699 && (TYPE_CODE (objtype) == TYPE_CODE_PTR
2700 || TYPE_CODE (objtype) == TYPE_CODE_REF))
2701 {
2702 temp = value_addr (temp);
2703 }
2704 *objp = temp;
2705 }
2706
2707 do_cleanups (all_cleanups);
2708
2709 switch (match_quality)
2710 {
2711 case INCOMPATIBLE:
2712 return 100;
2713 case NON_STANDARD:
2714 return 10;
2715 default: /* STANDARD */
2716 return 0;
2717 }
2718 }
2719
2720 /* Find the best overload match, searching for FUNC_NAME in namespaces
2721 contained in QUALIFIED_NAME until it either finds a good match or
2722 runs out of namespaces. It stores the overloaded functions in
2723 *OLOAD_SYMS, and the badness vector in *OLOAD_CHAMP_BV. The
2724 calling function is responsible for freeing *OLOAD_SYMS and
2725 *OLOAD_CHAMP_BV. If NO_ADL, argument dependent lookup is not
2726 performned. */
2727
2728 static int
2729 find_oload_champ_namespace (struct value **args, int nargs,
2730 const char *func_name,
2731 const char *qualified_name,
2732 struct symbol ***oload_syms,
2733 struct badness_vector **oload_champ_bv,
2734 const int no_adl)
2735 {
2736 int oload_champ;
2737
2738 find_oload_champ_namespace_loop (args, nargs,
2739 func_name,
2740 qualified_name, 0,
2741 oload_syms, oload_champ_bv,
2742 &oload_champ,
2743 no_adl);
2744
2745 return oload_champ;
2746 }
2747
2748 /* Helper function for find_oload_champ_namespace; NAMESPACE_LEN is
2749 how deep we've looked for namespaces, and the champ is stored in
2750 OLOAD_CHAMP. The return value is 1 if the champ is a good one, 0
2751 if it isn't. Other arguments are the same as in
2752 find_oload_champ_namespace
2753
2754 It is the caller's responsibility to free *OLOAD_SYMS and
2755 *OLOAD_CHAMP_BV. */
2756
2757 static int
2758 find_oload_champ_namespace_loop (struct value **args, int nargs,
2759 const char *func_name,
2760 const char *qualified_name,
2761 int namespace_len,
2762 struct symbol ***oload_syms,
2763 struct badness_vector **oload_champ_bv,
2764 int *oload_champ,
2765 const int no_adl)
2766 {
2767 int next_namespace_len = namespace_len;
2768 int searched_deeper = 0;
2769 int num_fns = 0;
2770 struct cleanup *old_cleanups;
2771 int new_oload_champ;
2772 struct symbol **new_oload_syms;
2773 struct badness_vector *new_oload_champ_bv;
2774 char *new_namespace;
2775
2776 if (next_namespace_len != 0)
2777 {
2778 gdb_assert (qualified_name[next_namespace_len] == ':');
2779 next_namespace_len += 2;
2780 }
2781 next_namespace_len +=
2782 cp_find_first_component (qualified_name + next_namespace_len);
2783
2784 /* Initialize these to values that can safely be xfree'd. */
2785 *oload_syms = NULL;
2786 *oload_champ_bv = NULL;
2787
2788 /* First, see if we have a deeper namespace we can search in.
2789 If we get a good match there, use it. */
2790
2791 if (qualified_name[next_namespace_len] == ':')
2792 {
2793 searched_deeper = 1;
2794
2795 if (find_oload_champ_namespace_loop (args, nargs,
2796 func_name, qualified_name,
2797 next_namespace_len,
2798 oload_syms, oload_champ_bv,
2799 oload_champ, no_adl))
2800 {
2801 return 1;
2802 }
2803 };
2804
2805 /* If we reach here, either we're in the deepest namespace or we
2806 didn't find a good match in a deeper namespace. But, in the
2807 latter case, we still have a bad match in a deeper namespace;
2808 note that we might not find any match at all in the current
2809 namespace. (There's always a match in the deepest namespace,
2810 because this overload mechanism only gets called if there's a
2811 function symbol to start off with.) */
2812
2813 old_cleanups = make_cleanup (xfree, *oload_syms);
2814 make_cleanup (xfree, *oload_champ_bv);
2815 new_namespace = alloca (namespace_len + 1);
2816 strncpy (new_namespace, qualified_name, namespace_len);
2817 new_namespace[namespace_len] = '\0';
2818 new_oload_syms = make_symbol_overload_list (func_name,
2819 new_namespace);
2820
2821 /* If we have reached the deepest level perform argument
2822 determined lookup. */
2823 if (!searched_deeper && !no_adl)
2824 {
2825 int ix;
2826 struct type **arg_types;
2827
2828 /* Prepare list of argument types for overload resolution. */
2829 arg_types = (struct type **)
2830 alloca (nargs * (sizeof (struct type *)));
2831 for (ix = 0; ix < nargs; ix++)
2832 arg_types[ix] = value_type (args[ix]);
2833 make_symbol_overload_list_adl (arg_types, nargs, func_name);
2834 }
2835
2836 while (new_oload_syms[num_fns])
2837 ++num_fns;
2838
2839 new_oload_champ = find_oload_champ (args, nargs, 0, num_fns,
2840 NULL, new_oload_syms,
2841 &new_oload_champ_bv);
2842
2843 /* Case 1: We found a good match. Free earlier matches (if any),
2844 and return it. Case 2: We didn't find a good match, but we're
2845 not the deepest function. Then go with the bad match that the
2846 deeper function found. Case 3: We found a bad match, and we're
2847 the deepest function. Then return what we found, even though
2848 it's a bad match. */
2849
2850 if (new_oload_champ != -1
2851 && classify_oload_match (new_oload_champ_bv, nargs, 0) == STANDARD)
2852 {
2853 *oload_syms = new_oload_syms;
2854 *oload_champ = new_oload_champ;
2855 *oload_champ_bv = new_oload_champ_bv;
2856 do_cleanups (old_cleanups);
2857 return 1;
2858 }
2859 else if (searched_deeper)
2860 {
2861 xfree (new_oload_syms);
2862 xfree (new_oload_champ_bv);
2863 discard_cleanups (old_cleanups);
2864 return 0;
2865 }
2866 else
2867 {
2868 *oload_syms = new_oload_syms;
2869 *oload_champ = new_oload_champ;
2870 *oload_champ_bv = new_oload_champ_bv;
2871 do_cleanups (old_cleanups);
2872 return 0;
2873 }
2874 }
2875
2876 /* Look for a function to take NARGS args of ARGS. Find
2877 the best match from among the overloaded methods or functions
2878 (depending on METHOD) given by FNS_PTR or OLOAD_SYMS, respectively.
2879 The number of methods/functions in the list is given by NUM_FNS.
2880 Return the index of the best match; store an indication of the
2881 quality of the match in OLOAD_CHAMP_BV.
2882
2883 It is the caller's responsibility to free *OLOAD_CHAMP_BV. */
2884
2885 static int
2886 find_oload_champ (struct value **args, int nargs, int method,
2887 int num_fns, struct fn_field *fns_ptr,
2888 struct symbol **oload_syms,
2889 struct badness_vector **oload_champ_bv)
2890 {
2891 int ix;
2892 /* A measure of how good an overloaded instance is. */
2893 struct badness_vector *bv;
2894 /* Index of best overloaded function. */
2895 int oload_champ = -1;
2896 /* Current ambiguity state for overload resolution. */
2897 int oload_ambiguous = 0;
2898 /* 0 => no ambiguity, 1 => two good funcs, 2 => incomparable funcs. */
2899
2900 *oload_champ_bv = NULL;
2901
2902 /* Consider each candidate in turn. */
2903 for (ix = 0; ix < num_fns; ix++)
2904 {
2905 int jj;
2906 int static_offset = oload_method_static (method, fns_ptr, ix);
2907 int nparms;
2908 struct type **parm_types;
2909
2910 if (method)
2911 {
2912 nparms = TYPE_NFIELDS (TYPE_FN_FIELD_TYPE (fns_ptr, ix));
2913 }
2914 else
2915 {
2916 /* If it's not a method, this is the proper place. */
2917 nparms = TYPE_NFIELDS (SYMBOL_TYPE (oload_syms[ix]));
2918 }
2919
2920 /* Prepare array of parameter types. */
2921 parm_types = (struct type **)
2922 xmalloc (nparms * (sizeof (struct type *)));
2923 for (jj = 0; jj < nparms; jj++)
2924 parm_types[jj] = (method
2925 ? (TYPE_FN_FIELD_ARGS (fns_ptr, ix)[jj].type)
2926 : TYPE_FIELD_TYPE (SYMBOL_TYPE (oload_syms[ix]),
2927 jj));
2928
2929 /* Compare parameter types to supplied argument types. Skip
2930 THIS for static methods. */
2931 bv = rank_function (parm_types, nparms,
2932 args + static_offset,
2933 nargs - static_offset);
2934
2935 if (!*oload_champ_bv)
2936 {
2937 *oload_champ_bv = bv;
2938 oload_champ = 0;
2939 }
2940 else /* See whether current candidate is better or worse than
2941 previous best. */
2942 switch (compare_badness (bv, *oload_champ_bv))
2943 {
2944 case 0: /* Top two contenders are equally good. */
2945 oload_ambiguous = 1;
2946 break;
2947 case 1: /* Incomparable top contenders. */
2948 oload_ambiguous = 2;
2949 break;
2950 case 2: /* New champion, record details. */
2951 *oload_champ_bv = bv;
2952 oload_ambiguous = 0;
2953 oload_champ = ix;
2954 break;
2955 case 3:
2956 default:
2957 break;
2958 }
2959 xfree (parm_types);
2960 if (overload_debug)
2961 {
2962 if (method)
2963 fprintf_filtered (gdb_stderr,
2964 "Overloaded method instance %s, # of parms %d\n",
2965 fns_ptr[ix].physname, nparms);
2966 else
2967 fprintf_filtered (gdb_stderr,
2968 "Overloaded function instance "
2969 "%s # of parms %d\n",
2970 SYMBOL_DEMANGLED_NAME (oload_syms[ix]),
2971 nparms);
2972 for (jj = 0; jj < nargs - static_offset; jj++)
2973 fprintf_filtered (gdb_stderr,
2974 "...Badness @ %d : %d\n",
2975 jj, bv->rank[jj].rank);
2976 fprintf_filtered (gdb_stderr, "Overload resolution "
2977 "champion is %d, ambiguous? %d\n",
2978 oload_champ, oload_ambiguous);
2979 }
2980 }
2981
2982 return oload_champ;
2983 }
2984
2985 /* Return 1 if we're looking at a static method, 0 if we're looking at
2986 a non-static method or a function that isn't a method. */
2987
2988 static int
2989 oload_method_static (int method, struct fn_field *fns_ptr, int index)
2990 {
2991 if (method && fns_ptr && index >= 0
2992 && TYPE_FN_FIELD_STATIC_P (fns_ptr, index))
2993 return 1;
2994 else
2995 return 0;
2996 }
2997
2998 /* Check how good an overload match OLOAD_CHAMP_BV represents. */
2999
3000 static enum oload_classification
3001 classify_oload_match (struct badness_vector *oload_champ_bv,
3002 int nargs,
3003 int static_offset)
3004 {
3005 int ix;
3006 enum oload_classification worst = STANDARD;
3007
3008 for (ix = 1; ix <= nargs - static_offset; ix++)
3009 {
3010 /* If this conversion is as bad as INCOMPATIBLE_TYPE_BADNESS
3011 or worse return INCOMPATIBLE. */
3012 if (compare_ranks (oload_champ_bv->rank[ix],
3013 INCOMPATIBLE_TYPE_BADNESS) <= 0)
3014 return INCOMPATIBLE; /* Truly mismatched types. */
3015 /* Otherwise If this conversion is as bad as
3016 NS_POINTER_CONVERSION_BADNESS or worse return NON_STANDARD. */
3017 else if (compare_ranks (oload_champ_bv->rank[ix],
3018 NS_POINTER_CONVERSION_BADNESS) <= 0)
3019 worst = NON_STANDARD; /* Non-standard type conversions
3020 needed. */
3021 }
3022
3023 /* If no INCOMPATIBLE classification was found, return the worst one
3024 that was found (if any). */
3025 return worst;
3026 }
3027
3028 /* C++: return 1 is NAME is a legitimate name for the destructor of
3029 type TYPE. If TYPE does not have a destructor, or if NAME is
3030 inappropriate for TYPE, an error is signaled. Parameter TYPE should not yet
3031 have CHECK_TYPEDEF applied, this function will apply it itself. */
3032
3033 int
3034 destructor_name_p (const char *name, struct type *type)
3035 {
3036 if (name[0] == '~')
3037 {
3038 const char *dname = type_name_no_tag_or_error (type);
3039 const char *cp = strchr (dname, '<');
3040 unsigned int len;
3041
3042 /* Do not compare the template part for template classes. */
3043 if (cp == NULL)
3044 len = strlen (dname);
3045 else
3046 len = cp - dname;
3047 if (strlen (name + 1) != len || strncmp (dname, name + 1, len) != 0)
3048 error (_("name of destructor must equal name of class"));
3049 else
3050 return 1;
3051 }
3052 return 0;
3053 }
3054
3055 /* C++: Given an aggregate type CURTYPE, and a member name NAME,
3056 return the appropriate member (or the address of the member, if
3057 WANT_ADDRESS). This function is used to resolve user expressions
3058 of the form "DOMAIN::NAME". For more details on what happens, see
3059 the comment before value_struct_elt_for_reference. */
3060
3061 struct value *
3062 value_aggregate_elt (struct type *curtype, char *name,
3063 struct type *expect_type, int want_address,
3064 enum noside noside)
3065 {
3066 switch (TYPE_CODE (curtype))
3067 {
3068 case TYPE_CODE_STRUCT:
3069 case TYPE_CODE_UNION:
3070 return value_struct_elt_for_reference (curtype, 0, curtype,
3071 name, expect_type,
3072 want_address, noside);
3073 case TYPE_CODE_NAMESPACE:
3074 return value_namespace_elt (curtype, name,
3075 want_address, noside);
3076 default:
3077 internal_error (__FILE__, __LINE__,
3078 _("non-aggregate type in value_aggregate_elt"));
3079 }
3080 }
3081
3082 /* Compares the two method/function types T1 and T2 for "equality"
3083 with respect to the methods' parameters. If the types of the
3084 two parameter lists are the same, returns 1; 0 otherwise. This
3085 comparison may ignore any artificial parameters in T1 if
3086 SKIP_ARTIFICIAL is non-zero. This function will ALWAYS skip
3087 the first artificial parameter in T1, assumed to be a 'this' pointer.
3088
3089 The type T2 is expected to have come from make_params (in eval.c). */
3090
3091 static int
3092 compare_parameters (struct type *t1, struct type *t2, int skip_artificial)
3093 {
3094 int start = 0;
3095
3096 if (TYPE_NFIELDS (t1) > 0 && TYPE_FIELD_ARTIFICIAL (t1, 0))
3097 ++start;
3098
3099 /* If skipping artificial fields, find the first real field
3100 in T1. */
3101 if (skip_artificial)
3102 {
3103 while (start < TYPE_NFIELDS (t1)
3104 && TYPE_FIELD_ARTIFICIAL (t1, start))
3105 ++start;
3106 }
3107
3108 /* Now compare parameters. */
3109
3110 /* Special case: a method taking void. T1 will contain no
3111 non-artificial fields, and T2 will contain TYPE_CODE_VOID. */
3112 if ((TYPE_NFIELDS (t1) - start) == 0 && TYPE_NFIELDS (t2) == 1
3113 && TYPE_CODE (TYPE_FIELD_TYPE (t2, 0)) == TYPE_CODE_VOID)
3114 return 1;
3115
3116 if ((TYPE_NFIELDS (t1) - start) == TYPE_NFIELDS (t2))
3117 {
3118 int i;
3119
3120 for (i = 0; i < TYPE_NFIELDS (t2); ++i)
3121 {
3122 if (compare_ranks (rank_one_type (TYPE_FIELD_TYPE (t1, start + i),
3123 TYPE_FIELD_TYPE (t2, i), NULL),
3124 EXACT_MATCH_BADNESS) != 0)
3125 return 0;
3126 }
3127
3128 return 1;
3129 }
3130
3131 return 0;
3132 }
3133
3134 /* C++: Given an aggregate type CURTYPE, and a member name NAME,
3135 return the address of this member as a "pointer to member" type.
3136 If INTYPE is non-null, then it will be the type of the member we
3137 are looking for. This will help us resolve "pointers to member
3138 functions". This function is used to resolve user expressions of
3139 the form "DOMAIN::NAME". */
3140
3141 static struct value *
3142 value_struct_elt_for_reference (struct type *domain, int offset,
3143 struct type *curtype, char *name,
3144 struct type *intype,
3145 int want_address,
3146 enum noside noside)
3147 {
3148 struct type *t = curtype;
3149 int i;
3150 struct value *v, *result;
3151
3152 if (TYPE_CODE (t) != TYPE_CODE_STRUCT
3153 && TYPE_CODE (t) != TYPE_CODE_UNION)
3154 error (_("Internal error: non-aggregate type "
3155 "to value_struct_elt_for_reference"));
3156
3157 for (i = TYPE_NFIELDS (t) - 1; i >= TYPE_N_BASECLASSES (t); i--)
3158 {
3159 const char *t_field_name = TYPE_FIELD_NAME (t, i);
3160
3161 if (t_field_name && strcmp (t_field_name, name) == 0)
3162 {
3163 if (field_is_static (&TYPE_FIELD (t, i)))
3164 {
3165 v = value_static_field (t, i);
3166 if (want_address)
3167 v = value_addr (v);
3168 return v;
3169 }
3170 if (TYPE_FIELD_PACKED (t, i))
3171 error (_("pointers to bitfield members not allowed"));
3172
3173 if (want_address)
3174 return value_from_longest
3175 (lookup_memberptr_type (TYPE_FIELD_TYPE (t, i), domain),
3176 offset + (LONGEST) (TYPE_FIELD_BITPOS (t, i) >> 3));
3177 else if (noside != EVAL_NORMAL)
3178 return allocate_value (TYPE_FIELD_TYPE (t, i));
3179 else
3180 {
3181 /* Try to evaluate NAME as a qualified name with implicit
3182 this pointer. In this case, attempt to return the
3183 equivalent to `this->*(&TYPE::NAME)'. */
3184 v = value_of_this_silent (current_language);
3185 if (v != NULL)
3186 {
3187 struct value *ptr;
3188 long mem_offset;
3189 struct type *type, *tmp;
3190
3191 ptr = value_aggregate_elt (domain, name, NULL, 1, noside);
3192 type = check_typedef (value_type (ptr));
3193 gdb_assert (type != NULL
3194 && TYPE_CODE (type) == TYPE_CODE_MEMBERPTR);
3195 tmp = lookup_pointer_type (TYPE_DOMAIN_TYPE (type));
3196 v = value_cast_pointers (tmp, v, 1);
3197 mem_offset = value_as_long (ptr);
3198 tmp = lookup_pointer_type (TYPE_TARGET_TYPE (type));
3199 result = value_from_pointer (tmp,
3200 value_as_long (v) + mem_offset);
3201 return value_ind (result);
3202 }
3203
3204 error (_("Cannot reference non-static field \"%s\""), name);
3205 }
3206 }
3207 }
3208
3209 /* C++: If it was not found as a data field, then try to return it
3210 as a pointer to a method. */
3211
3212 /* Perform all necessary dereferencing. */
3213 while (intype && TYPE_CODE (intype) == TYPE_CODE_PTR)
3214 intype = TYPE_TARGET_TYPE (intype);
3215
3216 for (i = TYPE_NFN_FIELDS (t) - 1; i >= 0; --i)
3217 {
3218 const char *t_field_name = TYPE_FN_FIELDLIST_NAME (t, i);
3219 char dem_opname[64];
3220
3221 if (strncmp (t_field_name, "__", 2) == 0
3222 || strncmp (t_field_name, "op", 2) == 0
3223 || strncmp (t_field_name, "type", 4) == 0)
3224 {
3225 if (cplus_demangle_opname (t_field_name,
3226 dem_opname, DMGL_ANSI))
3227 t_field_name = dem_opname;
3228 else if (cplus_demangle_opname (t_field_name,
3229 dem_opname, 0))
3230 t_field_name = dem_opname;
3231 }
3232 if (t_field_name && strcmp (t_field_name, name) == 0)
3233 {
3234 int j;
3235 int len = TYPE_FN_FIELDLIST_LENGTH (t, i);
3236 struct fn_field *f = TYPE_FN_FIELDLIST1 (t, i);
3237
3238 check_stub_method_group (t, i);
3239
3240 if (intype)
3241 {
3242 for (j = 0; j < len; ++j)
3243 {
3244 if (compare_parameters (TYPE_FN_FIELD_TYPE (f, j), intype, 0)
3245 || compare_parameters (TYPE_FN_FIELD_TYPE (f, j),
3246 intype, 1))
3247 break;
3248 }
3249
3250 if (j == len)
3251 error (_("no member function matches "
3252 "that type instantiation"));
3253 }
3254 else
3255 {
3256 int ii;
3257
3258 j = -1;
3259 for (ii = 0; ii < len; ++ii)
3260 {
3261 /* Skip artificial methods. This is necessary if,
3262 for example, the user wants to "print
3263 subclass::subclass" with only one user-defined
3264 constructor. There is no ambiguity in this case.
3265 We are careful here to allow artificial methods
3266 if they are the unique result. */
3267 if (TYPE_FN_FIELD_ARTIFICIAL (f, ii))
3268 {
3269 if (j == -1)
3270 j = ii;
3271 continue;
3272 }
3273
3274 /* Desired method is ambiguous if more than one
3275 method is defined. */
3276 if (j != -1 && !TYPE_FN_FIELD_ARTIFICIAL (f, j))
3277 error (_("non-unique member `%s' requires "
3278 "type instantiation"), name);
3279
3280 j = ii;
3281 }
3282
3283 if (j == -1)
3284 error (_("no matching member function"));
3285 }
3286
3287 if (TYPE_FN_FIELD_STATIC_P (f, j))
3288 {
3289 struct symbol *s =
3290 lookup_symbol (TYPE_FN_FIELD_PHYSNAME (f, j),
3291 0, VAR_DOMAIN, 0);
3292
3293 if (s == NULL)
3294 return NULL;
3295
3296 if (want_address)
3297 return value_addr (read_var_value (s, 0));
3298 else
3299 return read_var_value (s, 0);
3300 }
3301
3302 if (TYPE_FN_FIELD_VIRTUAL_P (f, j))
3303 {
3304 if (want_address)
3305 {
3306 result = allocate_value
3307 (lookup_methodptr_type (TYPE_FN_FIELD_TYPE (f, j)));
3308 cplus_make_method_ptr (value_type (result),
3309 value_contents_writeable (result),
3310 TYPE_FN_FIELD_VOFFSET (f, j), 1);
3311 }
3312 else if (noside == EVAL_AVOID_SIDE_EFFECTS)
3313 return allocate_value (TYPE_FN_FIELD_TYPE (f, j));
3314 else
3315 error (_("Cannot reference virtual member function \"%s\""),
3316 name);
3317 }
3318 else
3319 {
3320 struct symbol *s =
3321 lookup_symbol (TYPE_FN_FIELD_PHYSNAME (f, j),
3322 0, VAR_DOMAIN, 0);
3323
3324 if (s == NULL)
3325 return NULL;
3326
3327 v = read_var_value (s, 0);
3328 if (!want_address)
3329 result = v;
3330 else
3331 {
3332 result = allocate_value (lookup_methodptr_type (TYPE_FN_FIELD_TYPE (f, j)));
3333 cplus_make_method_ptr (value_type (result),
3334 value_contents_writeable (result),
3335 value_address (v), 0);
3336 }
3337 }
3338 return result;
3339 }
3340 }
3341 for (i = TYPE_N_BASECLASSES (t) - 1; i >= 0; i--)
3342 {
3343 struct value *v;
3344 int base_offset;
3345
3346 if (BASETYPE_VIA_VIRTUAL (t, i))
3347 base_offset = 0;
3348 else
3349 base_offset = TYPE_BASECLASS_BITPOS (t, i) / 8;
3350 v = value_struct_elt_for_reference (domain,
3351 offset + base_offset,
3352 TYPE_BASECLASS (t, i),
3353 name, intype,
3354 want_address, noside);
3355 if (v)
3356 return v;
3357 }
3358
3359 /* As a last chance, pretend that CURTYPE is a namespace, and look
3360 it up that way; this (frequently) works for types nested inside
3361 classes. */
3362
3363 return value_maybe_namespace_elt (curtype, name,
3364 want_address, noside);
3365 }
3366
3367 /* C++: Return the member NAME of the namespace given by the type
3368 CURTYPE. */
3369
3370 static struct value *
3371 value_namespace_elt (const struct type *curtype,
3372 char *name, int want_address,
3373 enum noside noside)
3374 {
3375 struct value *retval = value_maybe_namespace_elt (curtype, name,
3376 want_address,
3377 noside);
3378
3379 if (retval == NULL)
3380 error (_("No symbol \"%s\" in namespace \"%s\"."),
3381 name, TYPE_TAG_NAME (curtype));
3382
3383 return retval;
3384 }
3385
3386 /* A helper function used by value_namespace_elt and
3387 value_struct_elt_for_reference. It looks up NAME inside the
3388 context CURTYPE; this works if CURTYPE is a namespace or if CURTYPE
3389 is a class and NAME refers to a type in CURTYPE itself (as opposed
3390 to, say, some base class of CURTYPE). */
3391
3392 static struct value *
3393 value_maybe_namespace_elt (const struct type *curtype,
3394 char *name, int want_address,
3395 enum noside noside)
3396 {
3397 const char *namespace_name = TYPE_TAG_NAME (curtype);
3398 struct symbol *sym;
3399 struct value *result;
3400
3401 sym = cp_lookup_symbol_namespace (namespace_name, name,
3402 get_selected_block (0), VAR_DOMAIN);
3403
3404 if (sym == NULL)
3405 {
3406 char *concatenated_name = alloca (strlen (namespace_name) + 2
3407 + strlen (name) + 1);
3408
3409 sprintf (concatenated_name, "%s::%s", namespace_name, name);
3410 sym = lookup_static_symbol_aux (concatenated_name, VAR_DOMAIN);
3411 }
3412
3413 if (sym == NULL)
3414 return NULL;
3415 else if ((noside == EVAL_AVOID_SIDE_EFFECTS)
3416 && (SYMBOL_CLASS (sym) == LOC_TYPEDEF))
3417 result = allocate_value (SYMBOL_TYPE (sym));
3418 else
3419 result = value_of_variable (sym, get_selected_block (0));
3420
3421 if (result && want_address)
3422 result = value_addr (result);
3423
3424 return result;
3425 }
3426
3427 /* Given a pointer or a reference value V, find its real (RTTI) type.
3428
3429 Other parameters FULL, TOP, USING_ENC as with value_rtti_type()
3430 and refer to the values computed for the object pointed to. */
3431
3432 struct type *
3433 value_rtti_indirect_type (struct value *v, int *full,
3434 int *top, int *using_enc)
3435 {
3436 struct value *target;
3437 struct type *type, *real_type, *target_type;
3438
3439 type = value_type (v);
3440 type = check_typedef (type);
3441 if (TYPE_CODE (type) == TYPE_CODE_REF)
3442 target = coerce_ref (v);
3443 else if (TYPE_CODE (type) == TYPE_CODE_PTR)
3444 target = value_ind (v);
3445 else
3446 return NULL;
3447
3448 real_type = value_rtti_type (target, full, top, using_enc);
3449
3450 if (real_type)
3451 {
3452 /* Copy qualifiers to the referenced object. */
3453 target_type = value_type (target);
3454 real_type = make_cv_type (TYPE_CONST (target_type),
3455 TYPE_VOLATILE (target_type), real_type, NULL);
3456 if (TYPE_CODE (type) == TYPE_CODE_REF)
3457 real_type = lookup_reference_type (real_type);
3458 else if (TYPE_CODE (type) == TYPE_CODE_PTR)
3459 real_type = lookup_pointer_type (real_type);
3460 else
3461 internal_error (__FILE__, __LINE__, _("Unexpected value type."));
3462
3463 /* Copy qualifiers to the pointer/reference. */
3464 real_type = make_cv_type (TYPE_CONST (type), TYPE_VOLATILE (type),
3465 real_type, NULL);
3466 }
3467
3468 return real_type;
3469 }
3470
3471 /* Given a value pointed to by ARGP, check its real run-time type, and
3472 if that is different from the enclosing type, create a new value
3473 using the real run-time type as the enclosing type (and of the same
3474 type as ARGP) and return it, with the embedded offset adjusted to
3475 be the correct offset to the enclosed object. RTYPE is the type,
3476 and XFULL, XTOP, and XUSING_ENC are the other parameters, computed
3477 by value_rtti_type(). If these are available, they can be supplied
3478 and a second call to value_rtti_type() is avoided. (Pass RTYPE ==
3479 NULL if they're not available. */
3480
3481 struct value *
3482 value_full_object (struct value *argp,
3483 struct type *rtype,
3484 int xfull, int xtop,
3485 int xusing_enc)
3486 {
3487 struct type *real_type;
3488 int full = 0;
3489 int top = -1;
3490 int using_enc = 0;
3491 struct value *new_val;
3492
3493 if (rtype)
3494 {
3495 real_type = rtype;
3496 full = xfull;
3497 top = xtop;
3498 using_enc = xusing_enc;
3499 }
3500 else
3501 real_type = value_rtti_type (argp, &full, &top, &using_enc);
3502
3503 /* If no RTTI data, or if object is already complete, do nothing. */
3504 if (!real_type || real_type == value_enclosing_type (argp))
3505 return argp;
3506
3507 /* In a destructor we might see a real type that is a superclass of
3508 the object's type. In this case it is better to leave the object
3509 as-is. */
3510 if (full
3511 && TYPE_LENGTH (real_type) < TYPE_LENGTH (value_enclosing_type (argp)))
3512 return argp;
3513
3514 /* If we have the full object, but for some reason the enclosing
3515 type is wrong, set it. */
3516 /* pai: FIXME -- sounds iffy */
3517 if (full)
3518 {
3519 argp = value_copy (argp);
3520 set_value_enclosing_type (argp, real_type);
3521 return argp;
3522 }
3523
3524 /* Check if object is in memory. */
3525 if (VALUE_LVAL (argp) != lval_memory)
3526 {
3527 warning (_("Couldn't retrieve complete object of RTTI "
3528 "type %s; object may be in register(s)."),
3529 TYPE_NAME (real_type));
3530
3531 return argp;
3532 }
3533
3534 /* All other cases -- retrieve the complete object. */
3535 /* Go back by the computed top_offset from the beginning of the
3536 object, adjusting for the embedded offset of argp if that's what
3537 value_rtti_type used for its computation. */
3538 new_val = value_at_lazy (real_type, value_address (argp) - top +
3539 (using_enc ? 0 : value_embedded_offset (argp)));
3540 deprecated_set_value_type (new_val, value_type (argp));
3541 set_value_embedded_offset (new_val, (using_enc
3542 ? top + value_embedded_offset (argp)
3543 : top));
3544 return new_val;
3545 }
3546
3547
3548 /* Return the value of the local variable, if one exists. Throw error
3549 otherwise, such as if the request is made in an inappropriate context. */
3550
3551 struct value *
3552 value_of_this (const struct language_defn *lang)
3553 {
3554 struct symbol *sym;
3555 struct block *b;
3556 struct frame_info *frame;
3557
3558 if (!lang->la_name_of_this)
3559 error (_("no `this' in current language"));
3560
3561 frame = get_selected_frame (_("no frame selected"));
3562
3563 b = get_frame_block (frame, NULL);
3564
3565 sym = lookup_language_this (lang, b);
3566 if (sym == NULL)
3567 error (_("current stack frame does not contain a variable named `%s'"),
3568 lang->la_name_of_this);
3569
3570 return read_var_value (sym, frame);
3571 }
3572
3573 /* Return the value of the local variable, if one exists. Return NULL
3574 otherwise. Never throw error. */
3575
3576 struct value *
3577 value_of_this_silent (const struct language_defn *lang)
3578 {
3579 struct value *ret = NULL;
3580 volatile struct gdb_exception except;
3581
3582 TRY_CATCH (except, RETURN_MASK_ERROR)
3583 {
3584 ret = value_of_this (lang);
3585 }
3586
3587 return ret;
3588 }
3589
3590 /* Create a slice (sub-string, sub-array) of ARRAY, that is LENGTH
3591 elements long, starting at LOWBOUND. The result has the same lower
3592 bound as the original ARRAY. */
3593
3594 struct value *
3595 value_slice (struct value *array, int lowbound, int length)
3596 {
3597 struct type *slice_range_type, *slice_type, *range_type;
3598 LONGEST lowerbound, upperbound;
3599 struct value *slice;
3600 struct type *array_type;
3601
3602 array_type = check_typedef (value_type (array));
3603 if (TYPE_CODE (array_type) != TYPE_CODE_ARRAY
3604 && TYPE_CODE (array_type) != TYPE_CODE_STRING)
3605 error (_("cannot take slice of non-array"));
3606
3607 range_type = TYPE_INDEX_TYPE (array_type);
3608 if (get_discrete_bounds (range_type, &lowerbound, &upperbound) < 0)
3609 error (_("slice from bad array or bitstring"));
3610
3611 if (lowbound < lowerbound || length < 0
3612 || lowbound + length - 1 > upperbound)
3613 error (_("slice out of range"));
3614
3615 /* FIXME-type-allocation: need a way to free this type when we are
3616 done with it. */
3617 slice_range_type = create_range_type ((struct type *) NULL,
3618 TYPE_TARGET_TYPE (range_type),
3619 lowbound,
3620 lowbound + length - 1);
3621
3622 {
3623 struct type *element_type = TYPE_TARGET_TYPE (array_type);
3624 LONGEST offset =
3625 (lowbound - lowerbound) * TYPE_LENGTH (check_typedef (element_type));
3626
3627 slice_type = create_array_type ((struct type *) NULL,
3628 element_type,
3629 slice_range_type);
3630 TYPE_CODE (slice_type) = TYPE_CODE (array_type);
3631
3632 if (VALUE_LVAL (array) == lval_memory && value_lazy (array))
3633 slice = allocate_value_lazy (slice_type);
3634 else
3635 {
3636 slice = allocate_value (slice_type);
3637 value_contents_copy (slice, 0, array, offset,
3638 TYPE_LENGTH (slice_type));
3639 }
3640
3641 set_value_component_location (slice, array);
3642 VALUE_FRAME_ID (slice) = VALUE_FRAME_ID (array);
3643 set_value_offset (slice, value_offset (array) + offset);
3644 }
3645 return slice;
3646 }
3647
3648 /* Create a value for a FORTRAN complex number. Currently most of the
3649 time values are coerced to COMPLEX*16 (i.e. a complex number
3650 composed of 2 doubles. This really should be a smarter routine
3651 that figures out precision inteligently as opposed to assuming
3652 doubles. FIXME: fmb */
3653
3654 struct value *
3655 value_literal_complex (struct value *arg1,
3656 struct value *arg2,
3657 struct type *type)
3658 {
3659 struct value *val;
3660 struct type *real_type = TYPE_TARGET_TYPE (type);
3661
3662 val = allocate_value (type);
3663 arg1 = value_cast (real_type, arg1);
3664 arg2 = value_cast (real_type, arg2);
3665
3666 memcpy (value_contents_raw (val),
3667 value_contents (arg1), TYPE_LENGTH (real_type));
3668 memcpy (value_contents_raw (val) + TYPE_LENGTH (real_type),
3669 value_contents (arg2), TYPE_LENGTH (real_type));
3670 return val;
3671 }
3672
3673 /* Cast a value into the appropriate complex data type. */
3674
3675 static struct value *
3676 cast_into_complex (struct type *type, struct value *val)
3677 {
3678 struct type *real_type = TYPE_TARGET_TYPE (type);
3679
3680 if (TYPE_CODE (value_type (val)) == TYPE_CODE_COMPLEX)
3681 {
3682 struct type *val_real_type = TYPE_TARGET_TYPE (value_type (val));
3683 struct value *re_val = allocate_value (val_real_type);
3684 struct value *im_val = allocate_value (val_real_type);
3685
3686 memcpy (value_contents_raw (re_val),
3687 value_contents (val), TYPE_LENGTH (val_real_type));
3688 memcpy (value_contents_raw (im_val),
3689 value_contents (val) + TYPE_LENGTH (val_real_type),
3690 TYPE_LENGTH (val_real_type));
3691
3692 return value_literal_complex (re_val, im_val, type);
3693 }
3694 else if (TYPE_CODE (value_type (val)) == TYPE_CODE_FLT
3695 || TYPE_CODE (value_type (val)) == TYPE_CODE_INT)
3696 return value_literal_complex (val,
3697 value_zero (real_type, not_lval),
3698 type);
3699 else
3700 error (_("cannot cast non-number to complex"));
3701 }
3702
3703 void
3704 _initialize_valops (void)
3705 {
3706 add_setshow_boolean_cmd ("overload-resolution", class_support,
3707 &overload_resolution, _("\
3708 Set overload resolution in evaluating C++ functions."), _("\
3709 Show overload resolution in evaluating C++ functions."),
3710 NULL, NULL,
3711 show_overload_resolution,
3712 &setlist, &showlist);
3713 overload_resolution = 1;
3714 }
3715