type: add c99 variable length array support
[deliverable/binutils-gdb.git] / gdb / valops.c
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,
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 = BMSYMBOL_VALUE_ADDRESS (msymbol);
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_static_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 The type of the created value may differ from the passed type TYPE.
905 Make sure to retrieve the returned values's new type after this call
906 e.g. in case the type is a variable length array. */
907
908 static struct value *
909 get_value_at (struct type *type, CORE_ADDR addr, int lazy)
910 {
911 struct value *val;
912
913 if (TYPE_CODE (check_typedef (type)) == TYPE_CODE_VOID)
914 error (_("Attempt to dereference a generic pointer."));
915
916 val = value_from_contents_and_address (type, NULL, addr);
917
918 if (!lazy)
919 value_fetch_lazy (val);
920
921 return val;
922 }
923
924 /* Return a value with type TYPE located at ADDR.
925
926 Call value_at only if the data needs to be fetched immediately;
927 if we can be 'lazy' and defer the fetch, perhaps indefinately, call
928 value_at_lazy instead. value_at_lazy simply records the address of
929 the data and sets the lazy-evaluation-required flag. The lazy flag
930 is tested in the value_contents macro, which is used if and when
931 the contents are actually required. The type of the created value
932 may differ from the passed type TYPE. Make sure to retrieve the
933 returned values's new type after this call e.g. in case the type
934 is a variable length array.
935
936 Note: value_at does *NOT* handle embedded offsets; perform such
937 adjustments before or after calling it. */
938
939 struct value *
940 value_at (struct type *type, CORE_ADDR addr)
941 {
942 return get_value_at (type, addr, 0);
943 }
944
945 /* Return a lazy value with type TYPE located at ADDR (cf. value_at).
946 The type of the created value may differ from the passed type TYPE.
947 Make sure to retrieve the returned values's new type after this call
948 e.g. in case the type is a variable length array. */
949
950 struct value *
951 value_at_lazy (struct type *type, CORE_ADDR addr)
952 {
953 return get_value_at (type, addr, 1);
954 }
955
956 void
957 read_value_memory (struct value *val, int embedded_offset,
958 int stack, CORE_ADDR memaddr,
959 gdb_byte *buffer, size_t length)
960 {
961 ULONGEST xfered = 0;
962
963 while (xfered < length)
964 {
965 enum target_xfer_status status;
966 ULONGEST xfered_len;
967
968 status = target_xfer_partial (current_target.beneath,
969 TARGET_OBJECT_MEMORY, NULL,
970 buffer + xfered, NULL,
971 memaddr + xfered, length - xfered,
972 &xfered_len);
973
974 if (status == TARGET_XFER_OK)
975 /* nothing */;
976 else if (status == TARGET_XFER_UNAVAILABLE)
977 mark_value_bytes_unavailable (val, embedded_offset + xfered,
978 xfered_len);
979 else if (status == TARGET_XFER_EOF)
980 memory_error (TARGET_XFER_E_IO, memaddr + xfered);
981 else
982 memory_error (status, memaddr + xfered);
983
984 xfered += xfered_len;
985 QUIT;
986 }
987 }
988
989 /* Store the contents of FROMVAL into the location of TOVAL.
990 Return a new value with the location of TOVAL and contents of FROMVAL. */
991
992 struct value *
993 value_assign (struct value *toval, struct value *fromval)
994 {
995 struct type *type;
996 struct value *val;
997 struct frame_id old_frame;
998
999 if (!deprecated_value_modifiable (toval))
1000 error (_("Left operand of assignment is not a modifiable lvalue."));
1001
1002 toval = coerce_ref (toval);
1003
1004 type = value_type (toval);
1005 if (VALUE_LVAL (toval) != lval_internalvar)
1006 fromval = value_cast (type, fromval);
1007 else
1008 {
1009 /* Coerce arrays and functions to pointers, except for arrays
1010 which only live in GDB's storage. */
1011 if (!value_must_coerce_to_target (fromval))
1012 fromval = coerce_array (fromval);
1013 }
1014
1015 CHECK_TYPEDEF (type);
1016
1017 /* Since modifying a register can trash the frame chain, and
1018 modifying memory can trash the frame cache, we save the old frame
1019 and then restore the new frame afterwards. */
1020 old_frame = get_frame_id (deprecated_safe_get_selected_frame ());
1021
1022 switch (VALUE_LVAL (toval))
1023 {
1024 case lval_internalvar:
1025 set_internalvar (VALUE_INTERNALVAR (toval), fromval);
1026 return value_of_internalvar (get_type_arch (type),
1027 VALUE_INTERNALVAR (toval));
1028
1029 case lval_internalvar_component:
1030 {
1031 int offset = value_offset (toval);
1032
1033 /* Are we dealing with a bitfield?
1034
1035 It is important to mention that `value_parent (toval)' is
1036 non-NULL iff `value_bitsize (toval)' is non-zero. */
1037 if (value_bitsize (toval))
1038 {
1039 /* VALUE_INTERNALVAR below refers to the parent value, while
1040 the offset is relative to this parent value. */
1041 gdb_assert (value_parent (value_parent (toval)) == NULL);
1042 offset += value_offset (value_parent (toval));
1043 }
1044
1045 set_internalvar_component (VALUE_INTERNALVAR (toval),
1046 offset,
1047 value_bitpos (toval),
1048 value_bitsize (toval),
1049 fromval);
1050 }
1051 break;
1052
1053 case lval_memory:
1054 {
1055 const gdb_byte *dest_buffer;
1056 CORE_ADDR changed_addr;
1057 int changed_len;
1058 gdb_byte buffer[sizeof (LONGEST)];
1059
1060 if (value_bitsize (toval))
1061 {
1062 struct value *parent = value_parent (toval);
1063
1064 changed_addr = value_address (parent) + value_offset (toval);
1065 changed_len = (value_bitpos (toval)
1066 + value_bitsize (toval)
1067 + HOST_CHAR_BIT - 1)
1068 / HOST_CHAR_BIT;
1069
1070 /* If we can read-modify-write exactly the size of the
1071 containing type (e.g. short or int) then do so. This
1072 is safer for volatile bitfields mapped to hardware
1073 registers. */
1074 if (changed_len < TYPE_LENGTH (type)
1075 && TYPE_LENGTH (type) <= (int) sizeof (LONGEST)
1076 && ((LONGEST) changed_addr % TYPE_LENGTH (type)) == 0)
1077 changed_len = TYPE_LENGTH (type);
1078
1079 if (changed_len > (int) sizeof (LONGEST))
1080 error (_("Can't handle bitfields which "
1081 "don't fit in a %d bit word."),
1082 (int) sizeof (LONGEST) * HOST_CHAR_BIT);
1083
1084 read_memory (changed_addr, buffer, changed_len);
1085 modify_field (type, buffer, value_as_long (fromval),
1086 value_bitpos (toval), value_bitsize (toval));
1087 dest_buffer = buffer;
1088 }
1089 else
1090 {
1091 changed_addr = value_address (toval);
1092 changed_len = TYPE_LENGTH (type);
1093 dest_buffer = value_contents (fromval);
1094 }
1095
1096 write_memory_with_notification (changed_addr, dest_buffer, changed_len);
1097 }
1098 break;
1099
1100 case lval_register:
1101 {
1102 struct frame_info *frame;
1103 struct gdbarch *gdbarch;
1104 int value_reg;
1105
1106 /* Figure out which frame this is in currently. */
1107 frame = frame_find_by_id (VALUE_FRAME_ID (toval));
1108 value_reg = VALUE_REGNUM (toval);
1109
1110 if (!frame)
1111 error (_("Value being assigned to is no longer active."));
1112
1113 gdbarch = get_frame_arch (frame);
1114 if (gdbarch_convert_register_p (gdbarch, VALUE_REGNUM (toval), type))
1115 {
1116 /* If TOVAL is a special machine register requiring
1117 conversion of program values to a special raw
1118 format. */
1119 gdbarch_value_to_register (gdbarch, frame,
1120 VALUE_REGNUM (toval), type,
1121 value_contents (fromval));
1122 }
1123 else
1124 {
1125 if (value_bitsize (toval))
1126 {
1127 struct value *parent = value_parent (toval);
1128 int offset = value_offset (parent) + value_offset (toval);
1129 int changed_len;
1130 gdb_byte buffer[sizeof (LONGEST)];
1131 int optim, unavail;
1132
1133 changed_len = (value_bitpos (toval)
1134 + value_bitsize (toval)
1135 + HOST_CHAR_BIT - 1)
1136 / HOST_CHAR_BIT;
1137
1138 if (changed_len > (int) sizeof (LONGEST))
1139 error (_("Can't handle bitfields which "
1140 "don't fit in a %d bit word."),
1141 (int) sizeof (LONGEST) * HOST_CHAR_BIT);
1142
1143 if (!get_frame_register_bytes (frame, value_reg, offset,
1144 changed_len, buffer,
1145 &optim, &unavail))
1146 {
1147 if (optim)
1148 throw_error (OPTIMIZED_OUT_ERROR,
1149 _("value has been optimized out"));
1150 if (unavail)
1151 throw_error (NOT_AVAILABLE_ERROR,
1152 _("value is not available"));
1153 }
1154
1155 modify_field (type, buffer, value_as_long (fromval),
1156 value_bitpos (toval), value_bitsize (toval));
1157
1158 put_frame_register_bytes (frame, value_reg, offset,
1159 changed_len, buffer);
1160 }
1161 else
1162 {
1163 put_frame_register_bytes (frame, value_reg,
1164 value_offset (toval),
1165 TYPE_LENGTH (type),
1166 value_contents (fromval));
1167 }
1168 }
1169
1170 if (deprecated_register_changed_hook)
1171 deprecated_register_changed_hook (-1);
1172 break;
1173 }
1174
1175 case lval_computed:
1176 {
1177 const struct lval_funcs *funcs = value_computed_funcs (toval);
1178
1179 if (funcs->write != NULL)
1180 {
1181 funcs->write (toval, fromval);
1182 break;
1183 }
1184 }
1185 /* Fall through. */
1186
1187 default:
1188 error (_("Left operand of assignment is not an lvalue."));
1189 }
1190
1191 /* Assigning to the stack pointer, frame pointer, and other
1192 (architecture and calling convention specific) registers may
1193 cause the frame cache and regcache to be out of date. Assigning to memory
1194 also can. We just do this on all assignments to registers or
1195 memory, for simplicity's sake; I doubt the slowdown matters. */
1196 switch (VALUE_LVAL (toval))
1197 {
1198 case lval_memory:
1199 case lval_register:
1200 case lval_computed:
1201
1202 observer_notify_target_changed (&current_target);
1203
1204 /* Having destroyed the frame cache, restore the selected
1205 frame. */
1206
1207 /* FIXME: cagney/2002-11-02: There has to be a better way of
1208 doing this. Instead of constantly saving/restoring the
1209 frame. Why not create a get_selected_frame() function that,
1210 having saved the selected frame's ID can automatically
1211 re-find the previously selected frame automatically. */
1212
1213 {
1214 struct frame_info *fi = frame_find_by_id (old_frame);
1215
1216 if (fi != NULL)
1217 select_frame (fi);
1218 }
1219
1220 break;
1221 default:
1222 break;
1223 }
1224
1225 /* If the field does not entirely fill a LONGEST, then zero the sign
1226 bits. If the field is signed, and is negative, then sign
1227 extend. */
1228 if ((value_bitsize (toval) > 0)
1229 && (value_bitsize (toval) < 8 * (int) sizeof (LONGEST)))
1230 {
1231 LONGEST fieldval = value_as_long (fromval);
1232 LONGEST valmask = (((ULONGEST) 1) << value_bitsize (toval)) - 1;
1233
1234 fieldval &= valmask;
1235 if (!TYPE_UNSIGNED (type)
1236 && (fieldval & (valmask ^ (valmask >> 1))))
1237 fieldval |= ~valmask;
1238
1239 fromval = value_from_longest (type, fieldval);
1240 }
1241
1242 /* The return value is a copy of TOVAL so it shares its location
1243 information, but its contents are updated from FROMVAL. This
1244 implies the returned value is not lazy, even if TOVAL was. */
1245 val = value_copy (toval);
1246 set_value_lazy (val, 0);
1247 memcpy (value_contents_raw (val), value_contents (fromval),
1248 TYPE_LENGTH (type));
1249
1250 /* We copy over the enclosing type and pointed-to offset from FROMVAL
1251 in the case of pointer types. For object types, the enclosing type
1252 and embedded offset must *not* be copied: the target object refered
1253 to by TOVAL retains its original dynamic type after assignment. */
1254 if (TYPE_CODE (type) == TYPE_CODE_PTR)
1255 {
1256 set_value_enclosing_type (val, value_enclosing_type (fromval));
1257 set_value_pointed_to_offset (val, value_pointed_to_offset (fromval));
1258 }
1259
1260 return val;
1261 }
1262
1263 /* Extend a value VAL to COUNT repetitions of its type. */
1264
1265 struct value *
1266 value_repeat (struct value *arg1, int count)
1267 {
1268 struct value *val;
1269
1270 if (VALUE_LVAL (arg1) != lval_memory)
1271 error (_("Only values in memory can be extended with '@'."));
1272 if (count < 1)
1273 error (_("Invalid number %d of repetitions."), count);
1274
1275 val = allocate_repeat_value (value_enclosing_type (arg1), count);
1276
1277 VALUE_LVAL (val) = lval_memory;
1278 set_value_address (val, value_address (arg1));
1279
1280 read_value_memory (val, 0, value_stack (val), value_address (val),
1281 value_contents_all_raw (val),
1282 TYPE_LENGTH (value_enclosing_type (val)));
1283
1284 return val;
1285 }
1286
1287 struct value *
1288 value_of_variable (struct symbol *var, const struct block *b)
1289 {
1290 struct frame_info *frame;
1291
1292 if (!symbol_read_needs_frame (var))
1293 frame = NULL;
1294 else if (!b)
1295 frame = get_selected_frame (_("No frame selected."));
1296 else
1297 {
1298 frame = block_innermost_frame (b);
1299 if (!frame)
1300 {
1301 if (BLOCK_FUNCTION (b) && !block_inlined_p (b)
1302 && SYMBOL_PRINT_NAME (BLOCK_FUNCTION (b)))
1303 error (_("No frame is currently executing in block %s."),
1304 SYMBOL_PRINT_NAME (BLOCK_FUNCTION (b)));
1305 else
1306 error (_("No frame is currently executing in specified block"));
1307 }
1308 }
1309
1310 return read_var_value (var, frame);
1311 }
1312
1313 struct value *
1314 address_of_variable (struct symbol *var, const struct block *b)
1315 {
1316 struct type *type = SYMBOL_TYPE (var);
1317 struct value *val;
1318
1319 /* Evaluate it first; if the result is a memory address, we're fine.
1320 Lazy evaluation pays off here. */
1321
1322 val = value_of_variable (var, b);
1323
1324 if ((VALUE_LVAL (val) == lval_memory && value_lazy (val))
1325 || TYPE_CODE (type) == TYPE_CODE_FUNC)
1326 {
1327 CORE_ADDR addr = value_address (val);
1328
1329 return value_from_pointer (lookup_pointer_type (type), addr);
1330 }
1331
1332 /* Not a memory address; check what the problem was. */
1333 switch (VALUE_LVAL (val))
1334 {
1335 case lval_register:
1336 {
1337 struct frame_info *frame;
1338 const char *regname;
1339
1340 frame = frame_find_by_id (VALUE_FRAME_ID (val));
1341 gdb_assert (frame);
1342
1343 regname = gdbarch_register_name (get_frame_arch (frame),
1344 VALUE_REGNUM (val));
1345 gdb_assert (regname && *regname);
1346
1347 error (_("Address requested for identifier "
1348 "\"%s\" which is in register $%s"),
1349 SYMBOL_PRINT_NAME (var), regname);
1350 break;
1351 }
1352
1353 default:
1354 error (_("Can't take address of \"%s\" which isn't an lvalue."),
1355 SYMBOL_PRINT_NAME (var));
1356 break;
1357 }
1358
1359 return val;
1360 }
1361
1362 /* Return one if VAL does not live in target memory, but should in order
1363 to operate on it. Otherwise return zero. */
1364
1365 int
1366 value_must_coerce_to_target (struct value *val)
1367 {
1368 struct type *valtype;
1369
1370 /* The only lval kinds which do not live in target memory. */
1371 if (VALUE_LVAL (val) != not_lval
1372 && VALUE_LVAL (val) != lval_internalvar)
1373 return 0;
1374
1375 valtype = check_typedef (value_type (val));
1376
1377 switch (TYPE_CODE (valtype))
1378 {
1379 case TYPE_CODE_ARRAY:
1380 return TYPE_VECTOR (valtype) ? 0 : 1;
1381 case TYPE_CODE_STRING:
1382 return 1;
1383 default:
1384 return 0;
1385 }
1386 }
1387
1388 /* Make sure that VAL lives in target memory if it's supposed to. For
1389 instance, strings are constructed as character arrays in GDB's
1390 storage, and this function copies them to the target. */
1391
1392 struct value *
1393 value_coerce_to_target (struct value *val)
1394 {
1395 LONGEST length;
1396 CORE_ADDR addr;
1397
1398 if (!value_must_coerce_to_target (val))
1399 return val;
1400
1401 length = TYPE_LENGTH (check_typedef (value_type (val)));
1402 addr = allocate_space_in_inferior (length);
1403 write_memory (addr, value_contents (val), length);
1404 return value_at_lazy (value_type (val), addr);
1405 }
1406
1407 /* Given a value which is an array, return a value which is a pointer
1408 to its first element, regardless of whether or not the array has a
1409 nonzero lower bound.
1410
1411 FIXME: A previous comment here indicated that this routine should
1412 be substracting the array's lower bound. It's not clear to me that
1413 this is correct. Given an array subscripting operation, it would
1414 certainly work to do the adjustment here, essentially computing:
1415
1416 (&array[0] - (lowerbound * sizeof array[0])) + (index * sizeof array[0])
1417
1418 However I believe a more appropriate and logical place to account
1419 for the lower bound is to do so in value_subscript, essentially
1420 computing:
1421
1422 (&array[0] + ((index - lowerbound) * sizeof array[0]))
1423
1424 As further evidence consider what would happen with operations
1425 other than array subscripting, where the caller would get back a
1426 value that had an address somewhere before the actual first element
1427 of the array, and the information about the lower bound would be
1428 lost because of the coercion to pointer type. */
1429
1430 struct value *
1431 value_coerce_array (struct value *arg1)
1432 {
1433 struct type *type = check_typedef (value_type (arg1));
1434
1435 /* If the user tries to do something requiring a pointer with an
1436 array that has not yet been pushed to the target, then this would
1437 be a good time to do so. */
1438 arg1 = value_coerce_to_target (arg1);
1439
1440 if (VALUE_LVAL (arg1) != lval_memory)
1441 error (_("Attempt to take address of value not located in memory."));
1442
1443 return value_from_pointer (lookup_pointer_type (TYPE_TARGET_TYPE (type)),
1444 value_address (arg1));
1445 }
1446
1447 /* Given a value which is a function, return a value which is a pointer
1448 to it. */
1449
1450 struct value *
1451 value_coerce_function (struct value *arg1)
1452 {
1453 struct value *retval;
1454
1455 if (VALUE_LVAL (arg1) != lval_memory)
1456 error (_("Attempt to take address of value not located in memory."));
1457
1458 retval = value_from_pointer (lookup_pointer_type (value_type (arg1)),
1459 value_address (arg1));
1460 return retval;
1461 }
1462
1463 /* Return a pointer value for the object for which ARG1 is the
1464 contents. */
1465
1466 struct value *
1467 value_addr (struct value *arg1)
1468 {
1469 struct value *arg2;
1470 struct type *type = check_typedef (value_type (arg1));
1471
1472 if (TYPE_CODE (type) == TYPE_CODE_REF)
1473 {
1474 /* Copy the value, but change the type from (T&) to (T*). We
1475 keep the same location information, which is efficient, and
1476 allows &(&X) to get the location containing the reference. */
1477 arg2 = value_copy (arg1);
1478 deprecated_set_value_type (arg2,
1479 lookup_pointer_type (TYPE_TARGET_TYPE (type)));
1480 return arg2;
1481 }
1482 if (TYPE_CODE (type) == TYPE_CODE_FUNC)
1483 return value_coerce_function (arg1);
1484
1485 /* If this is an array that has not yet been pushed to the target,
1486 then this would be a good time to force it to memory. */
1487 arg1 = value_coerce_to_target (arg1);
1488
1489 if (VALUE_LVAL (arg1) != lval_memory)
1490 error (_("Attempt to take address of value not located in memory."));
1491
1492 /* Get target memory address. */
1493 arg2 = value_from_pointer (lookup_pointer_type (value_type (arg1)),
1494 (value_address (arg1)
1495 + value_embedded_offset (arg1)));
1496
1497 /* This may be a pointer to a base subobject; so remember the
1498 full derived object's type ... */
1499 set_value_enclosing_type (arg2,
1500 lookup_pointer_type (value_enclosing_type (arg1)));
1501 /* ... and also the relative position of the subobject in the full
1502 object. */
1503 set_value_pointed_to_offset (arg2, value_embedded_offset (arg1));
1504 return arg2;
1505 }
1506
1507 /* Return a reference value for the object for which ARG1 is the
1508 contents. */
1509
1510 struct value *
1511 value_ref (struct value *arg1)
1512 {
1513 struct value *arg2;
1514 struct type *type = check_typedef (value_type (arg1));
1515
1516 if (TYPE_CODE (type) == TYPE_CODE_REF)
1517 return arg1;
1518
1519 arg2 = value_addr (arg1);
1520 deprecated_set_value_type (arg2, lookup_reference_type (type));
1521 return arg2;
1522 }
1523
1524 /* Given a value of a pointer type, apply the C unary * operator to
1525 it. */
1526
1527 struct value *
1528 value_ind (struct value *arg1)
1529 {
1530 struct type *base_type;
1531 struct value *arg2;
1532
1533 arg1 = coerce_array (arg1);
1534
1535 base_type = check_typedef (value_type (arg1));
1536
1537 if (VALUE_LVAL (arg1) == lval_computed)
1538 {
1539 const struct lval_funcs *funcs = value_computed_funcs (arg1);
1540
1541 if (funcs->indirect)
1542 {
1543 struct value *result = funcs->indirect (arg1);
1544
1545 if (result)
1546 return result;
1547 }
1548 }
1549
1550 if (TYPE_CODE (base_type) == TYPE_CODE_PTR)
1551 {
1552 struct type *enc_type;
1553
1554 /* We may be pointing to something embedded in a larger object.
1555 Get the real type of the enclosing object. */
1556 enc_type = check_typedef (value_enclosing_type (arg1));
1557 enc_type = TYPE_TARGET_TYPE (enc_type);
1558
1559 if (TYPE_CODE (check_typedef (enc_type)) == TYPE_CODE_FUNC
1560 || TYPE_CODE (check_typedef (enc_type)) == TYPE_CODE_METHOD)
1561 /* For functions, go through find_function_addr, which knows
1562 how to handle function descriptors. */
1563 arg2 = value_at_lazy (enc_type,
1564 find_function_addr (arg1, NULL));
1565 else
1566 /* Retrieve the enclosing object pointed to. */
1567 arg2 = value_at_lazy (enc_type,
1568 (value_as_address (arg1)
1569 - value_pointed_to_offset (arg1)));
1570
1571 return readjust_indirect_value_type (arg2, enc_type, base_type, arg1);
1572 }
1573
1574 error (_("Attempt to take contents of a non-pointer value."));
1575 return 0; /* For lint -- never reached. */
1576 }
1577 \f
1578 /* Create a value for an array by allocating space in GDB, copying the
1579 data into that space, and then setting up an array value.
1580
1581 The array bounds are set from LOWBOUND and HIGHBOUND, and the array
1582 is populated from the values passed in ELEMVEC.
1583
1584 The element type of the array is inherited from the type of the
1585 first element, and all elements must have the same size (though we
1586 don't currently enforce any restriction on their types). */
1587
1588 struct value *
1589 value_array (int lowbound, int highbound, struct value **elemvec)
1590 {
1591 int nelem;
1592 int idx;
1593 unsigned int typelength;
1594 struct value *val;
1595 struct type *arraytype;
1596
1597 /* Validate that the bounds are reasonable and that each of the
1598 elements have the same size. */
1599
1600 nelem = highbound - lowbound + 1;
1601 if (nelem <= 0)
1602 {
1603 error (_("bad array bounds (%d, %d)"), lowbound, highbound);
1604 }
1605 typelength = TYPE_LENGTH (value_enclosing_type (elemvec[0]));
1606 for (idx = 1; idx < nelem; idx++)
1607 {
1608 if (TYPE_LENGTH (value_enclosing_type (elemvec[idx])) != typelength)
1609 {
1610 error (_("array elements must all be the same size"));
1611 }
1612 }
1613
1614 arraytype = lookup_array_range_type (value_enclosing_type (elemvec[0]),
1615 lowbound, highbound);
1616
1617 if (!current_language->c_style_arrays)
1618 {
1619 val = allocate_value (arraytype);
1620 for (idx = 0; idx < nelem; idx++)
1621 value_contents_copy (val, idx * typelength, elemvec[idx], 0,
1622 typelength);
1623 return val;
1624 }
1625
1626 /* Allocate space to store the array, and then initialize it by
1627 copying in each element. */
1628
1629 val = allocate_value (arraytype);
1630 for (idx = 0; idx < nelem; idx++)
1631 value_contents_copy (val, idx * typelength, elemvec[idx], 0, typelength);
1632 return val;
1633 }
1634
1635 struct value *
1636 value_cstring (char *ptr, ssize_t len, struct type *char_type)
1637 {
1638 struct value *val;
1639 int lowbound = current_language->string_lower_bound;
1640 ssize_t highbound = len / TYPE_LENGTH (char_type);
1641 struct type *stringtype
1642 = lookup_array_range_type (char_type, lowbound, highbound + lowbound - 1);
1643
1644 val = allocate_value (stringtype);
1645 memcpy (value_contents_raw (val), ptr, len);
1646 return val;
1647 }
1648
1649 /* Create a value for a string constant by allocating space in the
1650 inferior, copying the data into that space, and returning the
1651 address with type TYPE_CODE_STRING. PTR points to the string
1652 constant data; LEN is number of characters.
1653
1654 Note that string types are like array of char types with a lower
1655 bound of zero and an upper bound of LEN - 1. Also note that the
1656 string may contain embedded null bytes. */
1657
1658 struct value *
1659 value_string (char *ptr, ssize_t len, struct type *char_type)
1660 {
1661 struct value *val;
1662 int lowbound = current_language->string_lower_bound;
1663 ssize_t highbound = len / TYPE_LENGTH (char_type);
1664 struct type *stringtype
1665 = lookup_string_range_type (char_type, lowbound, highbound + lowbound - 1);
1666
1667 val = allocate_value (stringtype);
1668 memcpy (value_contents_raw (val), ptr, len);
1669 return val;
1670 }
1671
1672 \f
1673 /* See if we can pass arguments in T2 to a function which takes
1674 arguments of types T1. T1 is a list of NARGS arguments, and T2 is
1675 a NULL-terminated vector. If some arguments need coercion of some
1676 sort, then the coerced values are written into T2. Return value is
1677 0 if the arguments could be matched, or the position at which they
1678 differ if not.
1679
1680 STATICP is nonzero if the T1 argument list came from a static
1681 member function. T2 will still include the ``this'' pointer, but
1682 it will be skipped.
1683
1684 For non-static member functions, we ignore the first argument,
1685 which is the type of the instance variable. This is because we
1686 want to handle calls with objects from derived classes. This is
1687 not entirely correct: we should actually check to make sure that a
1688 requested operation is type secure, shouldn't we? FIXME. */
1689
1690 static int
1691 typecmp (int staticp, int varargs, int nargs,
1692 struct field t1[], struct value *t2[])
1693 {
1694 int i;
1695
1696 if (t2 == 0)
1697 internal_error (__FILE__, __LINE__,
1698 _("typecmp: no argument list"));
1699
1700 /* Skip ``this'' argument if applicable. T2 will always include
1701 THIS. */
1702 if (staticp)
1703 t2 ++;
1704
1705 for (i = 0;
1706 (i < nargs) && TYPE_CODE (t1[i].type) != TYPE_CODE_VOID;
1707 i++)
1708 {
1709 struct type *tt1, *tt2;
1710
1711 if (!t2[i])
1712 return i + 1;
1713
1714 tt1 = check_typedef (t1[i].type);
1715 tt2 = check_typedef (value_type (t2[i]));
1716
1717 if (TYPE_CODE (tt1) == TYPE_CODE_REF
1718 /* We should be doing hairy argument matching, as below. */
1719 && (TYPE_CODE (check_typedef (TYPE_TARGET_TYPE (tt1)))
1720 == TYPE_CODE (tt2)))
1721 {
1722 if (TYPE_CODE (tt2) == TYPE_CODE_ARRAY)
1723 t2[i] = value_coerce_array (t2[i]);
1724 else
1725 t2[i] = value_ref (t2[i]);
1726 continue;
1727 }
1728
1729 /* djb - 20000715 - Until the new type structure is in the
1730 place, and we can attempt things like implicit conversions,
1731 we need to do this so you can take something like a map<const
1732 char *>, and properly access map["hello"], because the
1733 argument to [] will be a reference to a pointer to a char,
1734 and the argument will be a pointer to a char. */
1735 while (TYPE_CODE(tt1) == TYPE_CODE_REF
1736 || TYPE_CODE (tt1) == TYPE_CODE_PTR)
1737 {
1738 tt1 = check_typedef( TYPE_TARGET_TYPE(tt1) );
1739 }
1740 while (TYPE_CODE(tt2) == TYPE_CODE_ARRAY
1741 || TYPE_CODE(tt2) == TYPE_CODE_PTR
1742 || TYPE_CODE(tt2) == TYPE_CODE_REF)
1743 {
1744 tt2 = check_typedef (TYPE_TARGET_TYPE(tt2));
1745 }
1746 if (TYPE_CODE (tt1) == TYPE_CODE (tt2))
1747 continue;
1748 /* Array to pointer is a `trivial conversion' according to the
1749 ARM. */
1750
1751 /* We should be doing much hairier argument matching (see
1752 section 13.2 of the ARM), but as a quick kludge, just check
1753 for the same type code. */
1754 if (TYPE_CODE (t1[i].type) != TYPE_CODE (value_type (t2[i])))
1755 return i + 1;
1756 }
1757 if (varargs || t2[i] == NULL)
1758 return 0;
1759 return i + 1;
1760 }
1761
1762 /* Helper class for do_search_struct_field that updates *RESULT_PTR
1763 and *LAST_BOFFSET, and possibly throws an exception if the field
1764 search has yielded ambiguous results. */
1765
1766 static void
1767 update_search_result (struct value **result_ptr, struct value *v,
1768 int *last_boffset, int boffset,
1769 const char *name, struct type *type)
1770 {
1771 if (v != NULL)
1772 {
1773 if (*result_ptr != NULL
1774 /* The result is not ambiguous if all the classes that are
1775 found occupy the same space. */
1776 && *last_boffset != boffset)
1777 error (_("base class '%s' is ambiguous in type '%s'"),
1778 name, TYPE_SAFE_NAME (type));
1779 *result_ptr = v;
1780 *last_boffset = boffset;
1781 }
1782 }
1783
1784 /* A helper for search_struct_field. This does all the work; most
1785 arguments are as passed to search_struct_field. The result is
1786 stored in *RESULT_PTR, which must be initialized to NULL.
1787 OUTERMOST_TYPE is the type of the initial type passed to
1788 search_struct_field; this is used for error reporting when the
1789 lookup is ambiguous. */
1790
1791 static void
1792 do_search_struct_field (const char *name, struct value *arg1, int offset,
1793 struct type *type, int looking_for_baseclass,
1794 struct value **result_ptr,
1795 int *last_boffset,
1796 struct type *outermost_type)
1797 {
1798 int i;
1799 int nbases;
1800
1801 CHECK_TYPEDEF (type);
1802 nbases = TYPE_N_BASECLASSES (type);
1803
1804 if (!looking_for_baseclass)
1805 for (i = TYPE_NFIELDS (type) - 1; i >= nbases; i--)
1806 {
1807 const char *t_field_name = TYPE_FIELD_NAME (type, i);
1808
1809 if (t_field_name && (strcmp_iw (t_field_name, name) == 0))
1810 {
1811 struct value *v;
1812
1813 if (field_is_static (&TYPE_FIELD (type, i)))
1814 v = value_static_field (type, i);
1815 else
1816 v = value_primitive_field (arg1, offset, i, type);
1817 *result_ptr = v;
1818 return;
1819 }
1820
1821 if (t_field_name
1822 && (t_field_name[0] == '\0'
1823 || (TYPE_CODE (type) == TYPE_CODE_UNION
1824 && (strcmp_iw (t_field_name, "else") == 0))))
1825 {
1826 struct type *field_type = TYPE_FIELD_TYPE (type, i);
1827
1828 if (TYPE_CODE (field_type) == TYPE_CODE_UNION
1829 || TYPE_CODE (field_type) == TYPE_CODE_STRUCT)
1830 {
1831 /* Look for a match through the fields of an anonymous
1832 union, or anonymous struct. C++ provides anonymous
1833 unions.
1834
1835 In the GNU Chill (now deleted from GDB)
1836 implementation of variant record types, each
1837 <alternative field> has an (anonymous) union type,
1838 each member of the union represents a <variant
1839 alternative>. Each <variant alternative> is
1840 represented as a struct, with a member for each
1841 <variant field>. */
1842
1843 struct value *v = NULL;
1844 int new_offset = offset;
1845
1846 /* This is pretty gross. In G++, the offset in an
1847 anonymous union is relative to the beginning of the
1848 enclosing struct. In the GNU Chill (now deleted
1849 from GDB) implementation of variant records, the
1850 bitpos is zero in an anonymous union field, so we
1851 have to add the offset of the union here. */
1852 if (TYPE_CODE (field_type) == TYPE_CODE_STRUCT
1853 || (TYPE_NFIELDS (field_type) > 0
1854 && TYPE_FIELD_BITPOS (field_type, 0) == 0))
1855 new_offset += TYPE_FIELD_BITPOS (type, i) / 8;
1856
1857 do_search_struct_field (name, arg1, new_offset,
1858 field_type,
1859 looking_for_baseclass, &v,
1860 last_boffset,
1861 outermost_type);
1862 if (v)
1863 {
1864 *result_ptr = v;
1865 return;
1866 }
1867 }
1868 }
1869 }
1870
1871 for (i = 0; i < nbases; i++)
1872 {
1873 struct value *v = NULL;
1874 struct type *basetype = check_typedef (TYPE_BASECLASS (type, i));
1875 /* If we are looking for baseclasses, this is what we get when
1876 we hit them. But it could happen that the base part's member
1877 name is not yet filled in. */
1878 int found_baseclass = (looking_for_baseclass
1879 && TYPE_BASECLASS_NAME (type, i) != NULL
1880 && (strcmp_iw (name,
1881 TYPE_BASECLASS_NAME (type,
1882 i)) == 0));
1883 int boffset = value_embedded_offset (arg1) + offset;
1884
1885 if (BASETYPE_VIA_VIRTUAL (type, i))
1886 {
1887 struct value *v2;
1888
1889 boffset = baseclass_offset (type, i,
1890 value_contents_for_printing (arg1),
1891 value_embedded_offset (arg1) + offset,
1892 value_address (arg1),
1893 arg1);
1894
1895 /* The virtual base class pointer might have been clobbered
1896 by the user program. Make sure that it still points to a
1897 valid memory location. */
1898
1899 boffset += value_embedded_offset (arg1) + offset;
1900 if (boffset < 0
1901 || boffset >= TYPE_LENGTH (value_enclosing_type (arg1)))
1902 {
1903 CORE_ADDR base_addr;
1904
1905 base_addr = value_address (arg1) + boffset;
1906 v2 = value_at_lazy (basetype, base_addr);
1907 if (target_read_memory (base_addr,
1908 value_contents_raw (v2),
1909 TYPE_LENGTH (value_type (v2))) != 0)
1910 error (_("virtual baseclass botch"));
1911 }
1912 else
1913 {
1914 v2 = value_copy (arg1);
1915 deprecated_set_value_type (v2, basetype);
1916 set_value_embedded_offset (v2, boffset);
1917 }
1918
1919 if (found_baseclass)
1920 v = v2;
1921 else
1922 {
1923 do_search_struct_field (name, v2, 0,
1924 TYPE_BASECLASS (type, i),
1925 looking_for_baseclass,
1926 result_ptr, last_boffset,
1927 outermost_type);
1928 }
1929 }
1930 else if (found_baseclass)
1931 v = value_primitive_field (arg1, offset, i, type);
1932 else
1933 {
1934 do_search_struct_field (name, arg1,
1935 offset + TYPE_BASECLASS_BITPOS (type,
1936 i) / 8,
1937 basetype, looking_for_baseclass,
1938 result_ptr, last_boffset,
1939 outermost_type);
1940 }
1941
1942 update_search_result (result_ptr, v, last_boffset,
1943 boffset, name, outermost_type);
1944 }
1945 }
1946
1947 /* Helper function used by value_struct_elt to recurse through
1948 baseclasses. Look for a field NAME in ARG1. Adjust the address of
1949 ARG1 by OFFSET bytes, and search in it assuming it has (class) type
1950 TYPE. If found, return value, else return NULL.
1951
1952 If LOOKING_FOR_BASECLASS, then instead of looking for struct
1953 fields, look for a baseclass named NAME. */
1954
1955 static struct value *
1956 search_struct_field (const char *name, struct value *arg1, int offset,
1957 struct type *type, int looking_for_baseclass)
1958 {
1959 struct value *result = NULL;
1960 int boffset = 0;
1961
1962 do_search_struct_field (name, arg1, offset, type, looking_for_baseclass,
1963 &result, &boffset, type);
1964 return result;
1965 }
1966
1967 /* Helper function used by value_struct_elt to recurse through
1968 baseclasses. Look for a field NAME in ARG1. Adjust the address of
1969 ARG1 by OFFSET bytes, and search in it assuming it has (class) type
1970 TYPE.
1971
1972 If found, return value, else if name matched and args not return
1973 (value) -1, else return NULL. */
1974
1975 static struct value *
1976 search_struct_method (const char *name, struct value **arg1p,
1977 struct value **args, int offset,
1978 int *static_memfuncp, struct type *type)
1979 {
1980 int i;
1981 struct value *v;
1982 int name_matched = 0;
1983 char dem_opname[64];
1984
1985 CHECK_TYPEDEF (type);
1986 for (i = TYPE_NFN_FIELDS (type) - 1; i >= 0; i--)
1987 {
1988 const char *t_field_name = TYPE_FN_FIELDLIST_NAME (type, i);
1989
1990 /* FIXME! May need to check for ARM demangling here. */
1991 if (strncmp (t_field_name, "__", 2) == 0 ||
1992 strncmp (t_field_name, "op", 2) == 0 ||
1993 strncmp (t_field_name, "type", 4) == 0)
1994 {
1995 if (cplus_demangle_opname (t_field_name, dem_opname, DMGL_ANSI))
1996 t_field_name = dem_opname;
1997 else if (cplus_demangle_opname (t_field_name, dem_opname, 0))
1998 t_field_name = dem_opname;
1999 }
2000 if (t_field_name && (strcmp_iw (t_field_name, name) == 0))
2001 {
2002 int j = TYPE_FN_FIELDLIST_LENGTH (type, i) - 1;
2003 struct fn_field *f = TYPE_FN_FIELDLIST1 (type, i);
2004
2005 name_matched = 1;
2006 check_stub_method_group (type, i);
2007 if (j > 0 && args == 0)
2008 error (_("cannot resolve overloaded method "
2009 "`%s': no arguments supplied"), name);
2010 else if (j == 0 && args == 0)
2011 {
2012 v = value_fn_field (arg1p, f, j, type, offset);
2013 if (v != NULL)
2014 return v;
2015 }
2016 else
2017 while (j >= 0)
2018 {
2019 if (!typecmp (TYPE_FN_FIELD_STATIC_P (f, j),
2020 TYPE_VARARGS (TYPE_FN_FIELD_TYPE (f, j)),
2021 TYPE_NFIELDS (TYPE_FN_FIELD_TYPE (f, j)),
2022 TYPE_FN_FIELD_ARGS (f, j), args))
2023 {
2024 if (TYPE_FN_FIELD_VIRTUAL_P (f, j))
2025 return value_virtual_fn_field (arg1p, f, j,
2026 type, offset);
2027 if (TYPE_FN_FIELD_STATIC_P (f, j)
2028 && static_memfuncp)
2029 *static_memfuncp = 1;
2030 v = value_fn_field (arg1p, f, j, type, offset);
2031 if (v != NULL)
2032 return v;
2033 }
2034 j--;
2035 }
2036 }
2037 }
2038
2039 for (i = TYPE_N_BASECLASSES (type) - 1; i >= 0; i--)
2040 {
2041 int base_offset;
2042 int this_offset;
2043
2044 if (BASETYPE_VIA_VIRTUAL (type, i))
2045 {
2046 struct type *baseclass = check_typedef (TYPE_BASECLASS (type, i));
2047 struct value *base_val;
2048 const gdb_byte *base_valaddr;
2049
2050 /* The virtual base class pointer might have been
2051 clobbered by the user program. Make sure that it
2052 still points to a valid memory location. */
2053
2054 if (offset < 0 || offset >= TYPE_LENGTH (type))
2055 {
2056 gdb_byte *tmp;
2057 struct cleanup *back_to;
2058 CORE_ADDR address;
2059
2060 tmp = xmalloc (TYPE_LENGTH (baseclass));
2061 back_to = make_cleanup (xfree, tmp);
2062 address = value_address (*arg1p);
2063
2064 if (target_read_memory (address + offset,
2065 tmp, TYPE_LENGTH (baseclass)) != 0)
2066 error (_("virtual baseclass botch"));
2067
2068 base_val = value_from_contents_and_address (baseclass,
2069 tmp,
2070 address + offset);
2071 base_valaddr = value_contents_for_printing (base_val);
2072 this_offset = 0;
2073 do_cleanups (back_to);
2074 }
2075 else
2076 {
2077 base_val = *arg1p;
2078 base_valaddr = value_contents_for_printing (*arg1p);
2079 this_offset = offset;
2080 }
2081
2082 base_offset = baseclass_offset (type, i, base_valaddr,
2083 this_offset, value_address (base_val),
2084 base_val);
2085 }
2086 else
2087 {
2088 base_offset = TYPE_BASECLASS_BITPOS (type, i) / 8;
2089 }
2090 v = search_struct_method (name, arg1p, args, base_offset + offset,
2091 static_memfuncp, TYPE_BASECLASS (type, i));
2092 if (v == (struct value *) - 1)
2093 {
2094 name_matched = 1;
2095 }
2096 else if (v)
2097 {
2098 /* FIXME-bothner: Why is this commented out? Why is it here? */
2099 /* *arg1p = arg1_tmp; */
2100 return v;
2101 }
2102 }
2103 if (name_matched)
2104 return (struct value *) - 1;
2105 else
2106 return NULL;
2107 }
2108
2109 /* Given *ARGP, a value of type (pointer to a)* structure/union,
2110 extract the component named NAME from the ultimate target
2111 structure/union and return it as a value with its appropriate type.
2112 ERR is used in the error message if *ARGP's type is wrong.
2113
2114 C++: ARGS is a list of argument types to aid in the selection of
2115 an appropriate method. Also, handle derived types.
2116
2117 STATIC_MEMFUNCP, if non-NULL, points to a caller-supplied location
2118 where the truthvalue of whether the function that was resolved was
2119 a static member function or not is stored.
2120
2121 ERR is an error message to be printed in case the field is not
2122 found. */
2123
2124 struct value *
2125 value_struct_elt (struct value **argp, struct value **args,
2126 const char *name, int *static_memfuncp, const char *err)
2127 {
2128 struct type *t;
2129 struct value *v;
2130
2131 *argp = coerce_array (*argp);
2132
2133 t = check_typedef (value_type (*argp));
2134
2135 /* Follow pointers until we get to a non-pointer. */
2136
2137 while (TYPE_CODE (t) == TYPE_CODE_PTR || TYPE_CODE (t) == TYPE_CODE_REF)
2138 {
2139 *argp = value_ind (*argp);
2140 /* Don't coerce fn pointer to fn and then back again! */
2141 if (TYPE_CODE (check_typedef (value_type (*argp))) != TYPE_CODE_FUNC)
2142 *argp = coerce_array (*argp);
2143 t = check_typedef (value_type (*argp));
2144 }
2145
2146 if (TYPE_CODE (t) != TYPE_CODE_STRUCT
2147 && TYPE_CODE (t) != TYPE_CODE_UNION)
2148 error (_("Attempt to extract a component of a value that is not a %s."),
2149 err);
2150
2151 /* Assume it's not, unless we see that it is. */
2152 if (static_memfuncp)
2153 *static_memfuncp = 0;
2154
2155 if (!args)
2156 {
2157 /* if there are no arguments ...do this... */
2158
2159 /* Try as a field first, because if we succeed, there is less
2160 work to be done. */
2161 v = search_struct_field (name, *argp, 0, t, 0);
2162 if (v)
2163 return v;
2164
2165 /* C++: If it was not found as a data field, then try to
2166 return it as a pointer to a method. */
2167 v = search_struct_method (name, argp, args, 0,
2168 static_memfuncp, t);
2169
2170 if (v == (struct value *) - 1)
2171 error (_("Cannot take address of method %s."), name);
2172 else if (v == 0)
2173 {
2174 if (TYPE_NFN_FIELDS (t))
2175 error (_("There is no member or method named %s."), name);
2176 else
2177 error (_("There is no member named %s."), name);
2178 }
2179 return v;
2180 }
2181
2182 v = search_struct_method (name, argp, args, 0,
2183 static_memfuncp, t);
2184
2185 if (v == (struct value *) - 1)
2186 {
2187 error (_("One of the arguments you tried to pass to %s could not "
2188 "be converted to what the function wants."), name);
2189 }
2190 else if (v == 0)
2191 {
2192 /* See if user tried to invoke data as function. If so, hand it
2193 back. If it's not callable (i.e., a pointer to function),
2194 gdb should give an error. */
2195 v = search_struct_field (name, *argp, 0, t, 0);
2196 /* If we found an ordinary field, then it is not a method call.
2197 So, treat it as if it were a static member function. */
2198 if (v && static_memfuncp)
2199 *static_memfuncp = 1;
2200 }
2201
2202 if (!v)
2203 throw_error (NOT_FOUND_ERROR,
2204 _("Structure has no component named %s."), name);
2205 return v;
2206 }
2207
2208 /* Given *ARGP, a value of type structure or union, or a pointer/reference
2209 to a structure or union, extract and return its component (field) of
2210 type FTYPE at the specified BITPOS.
2211 Throw an exception on error. */
2212
2213 struct value *
2214 value_struct_elt_bitpos (struct value **argp, int bitpos, struct type *ftype,
2215 const char *err)
2216 {
2217 struct type *t;
2218 struct value *v;
2219 int i;
2220 int nbases;
2221
2222 *argp = coerce_array (*argp);
2223
2224 t = check_typedef (value_type (*argp));
2225
2226 while (TYPE_CODE (t) == TYPE_CODE_PTR || TYPE_CODE (t) == TYPE_CODE_REF)
2227 {
2228 *argp = value_ind (*argp);
2229 if (TYPE_CODE (check_typedef (value_type (*argp))) != TYPE_CODE_FUNC)
2230 *argp = coerce_array (*argp);
2231 t = check_typedef (value_type (*argp));
2232 }
2233
2234 if (TYPE_CODE (t) != TYPE_CODE_STRUCT
2235 && TYPE_CODE (t) != TYPE_CODE_UNION)
2236 error (_("Attempt to extract a component of a value that is not a %s."),
2237 err);
2238
2239 for (i = TYPE_N_BASECLASSES (t); i < TYPE_NFIELDS (t); i++)
2240 {
2241 if (!field_is_static (&TYPE_FIELD (t, i))
2242 && bitpos == TYPE_FIELD_BITPOS (t, i)
2243 && types_equal (ftype, TYPE_FIELD_TYPE (t, i)))
2244 return value_primitive_field (*argp, 0, i, t);
2245 }
2246
2247 error (_("No field with matching bitpos and type."));
2248
2249 /* Never hit. */
2250 return NULL;
2251 }
2252
2253 /* Search through the methods of an object (and its bases) to find a
2254 specified method. Return the pointer to the fn_field list of
2255 overloaded instances.
2256
2257 Helper function for value_find_oload_list.
2258 ARGP is a pointer to a pointer to a value (the object).
2259 METHOD is a string containing the method name.
2260 OFFSET is the offset within the value.
2261 TYPE is the assumed type of the object.
2262 NUM_FNS is the number of overloaded instances.
2263 BASETYPE is set to the actual type of the subobject where the
2264 method is found.
2265 BOFFSET is the offset of the base subobject where the method is found. */
2266
2267 static struct fn_field *
2268 find_method_list (struct value **argp, const char *method,
2269 int offset, struct type *type, int *num_fns,
2270 struct type **basetype, int *boffset)
2271 {
2272 int i;
2273 struct fn_field *f;
2274 CHECK_TYPEDEF (type);
2275
2276 *num_fns = 0;
2277
2278 /* First check in object itself. */
2279 for (i = TYPE_NFN_FIELDS (type) - 1; i >= 0; i--)
2280 {
2281 /* pai: FIXME What about operators and type conversions? */
2282 const char *fn_field_name = TYPE_FN_FIELDLIST_NAME (type, i);
2283
2284 if (fn_field_name && (strcmp_iw (fn_field_name, method) == 0))
2285 {
2286 int len = TYPE_FN_FIELDLIST_LENGTH (type, i);
2287 struct fn_field *f = TYPE_FN_FIELDLIST1 (type, i);
2288
2289 *num_fns = len;
2290 *basetype = type;
2291 *boffset = offset;
2292
2293 /* Resolve any stub methods. */
2294 check_stub_method_group (type, i);
2295
2296 return f;
2297 }
2298 }
2299
2300 /* Not found in object, check in base subobjects. */
2301 for (i = TYPE_N_BASECLASSES (type) - 1; i >= 0; i--)
2302 {
2303 int base_offset;
2304
2305 if (BASETYPE_VIA_VIRTUAL (type, i))
2306 {
2307 base_offset = baseclass_offset (type, i,
2308 value_contents_for_printing (*argp),
2309 value_offset (*argp) + offset,
2310 value_address (*argp), *argp);
2311 }
2312 else /* Non-virtual base, simply use bit position from debug
2313 info. */
2314 {
2315 base_offset = TYPE_BASECLASS_BITPOS (type, i) / 8;
2316 }
2317 f = find_method_list (argp, method, base_offset + offset,
2318 TYPE_BASECLASS (type, i), num_fns,
2319 basetype, boffset);
2320 if (f)
2321 return f;
2322 }
2323 return NULL;
2324 }
2325
2326 /* Return the list of overloaded methods of a specified name.
2327
2328 ARGP is a pointer to a pointer to a value (the object).
2329 METHOD is the method name.
2330 OFFSET is the offset within the value contents.
2331 NUM_FNS is the number of overloaded instances.
2332 BASETYPE is set to the type of the base subobject that defines the
2333 method.
2334 BOFFSET is the offset of the base subobject which defines the method. */
2335
2336 static struct fn_field *
2337 value_find_oload_method_list (struct value **argp, const char *method,
2338 int offset, int *num_fns,
2339 struct type **basetype, int *boffset)
2340 {
2341 struct type *t;
2342
2343 t = check_typedef (value_type (*argp));
2344
2345 /* Code snarfed from value_struct_elt. */
2346 while (TYPE_CODE (t) == TYPE_CODE_PTR || TYPE_CODE (t) == TYPE_CODE_REF)
2347 {
2348 *argp = value_ind (*argp);
2349 /* Don't coerce fn pointer to fn and then back again! */
2350 if (TYPE_CODE (check_typedef (value_type (*argp))) != TYPE_CODE_FUNC)
2351 *argp = coerce_array (*argp);
2352 t = check_typedef (value_type (*argp));
2353 }
2354
2355 if (TYPE_CODE (t) != TYPE_CODE_STRUCT
2356 && TYPE_CODE (t) != TYPE_CODE_UNION)
2357 error (_("Attempt to extract a component of a "
2358 "value that is not a struct or union"));
2359
2360 return find_method_list (argp, method, 0, t, num_fns,
2361 basetype, boffset);
2362 }
2363
2364 /* Given an array of arguments (ARGS) (which includes an
2365 entry for "this" in the case of C++ methods), the number of
2366 arguments NARGS, the NAME of a function, and whether it's a method or
2367 not (METHOD), find the best function that matches on the argument types
2368 according to the overload resolution rules.
2369
2370 METHOD can be one of three values:
2371 NON_METHOD for non-member functions.
2372 METHOD: for member functions.
2373 BOTH: used for overload resolution of operators where the
2374 candidates are expected to be either member or non member
2375 functions. In this case the first argument ARGTYPES
2376 (representing 'this') is expected to be a reference to the
2377 target object, and will be dereferenced when attempting the
2378 non-member search.
2379
2380 In the case of class methods, the parameter OBJ is an object value
2381 in which to search for overloaded methods.
2382
2383 In the case of non-method functions, the parameter FSYM is a symbol
2384 corresponding to one of the overloaded functions.
2385
2386 Return value is an integer: 0 -> good match, 10 -> debugger applied
2387 non-standard coercions, 100 -> incompatible.
2388
2389 If a method is being searched for, VALP will hold the value.
2390 If a non-method is being searched for, SYMP will hold the symbol
2391 for it.
2392
2393 If a method is being searched for, and it is a static method,
2394 then STATICP will point to a non-zero value.
2395
2396 If NO_ADL argument dependent lookup is disabled. This is used to prevent
2397 ADL overload candidates when performing overload resolution for a fully
2398 qualified name.
2399
2400 Note: This function does *not* check the value of
2401 overload_resolution. Caller must check it to see whether overload
2402 resolution is permitted. */
2403
2404 int
2405 find_overload_match (struct value **args, int nargs,
2406 const char *name, enum oload_search_type method,
2407 struct value **objp, struct symbol *fsym,
2408 struct value **valp, struct symbol **symp,
2409 int *staticp, const int no_adl)
2410 {
2411 struct value *obj = (objp ? *objp : NULL);
2412 struct type *obj_type = obj ? value_type (obj) : NULL;
2413 /* Index of best overloaded function. */
2414 int func_oload_champ = -1;
2415 int method_oload_champ = -1;
2416
2417 /* The measure for the current best match. */
2418 struct badness_vector *method_badness = NULL;
2419 struct badness_vector *func_badness = NULL;
2420
2421 struct value *temp = obj;
2422 /* For methods, the list of overloaded methods. */
2423 struct fn_field *fns_ptr = NULL;
2424 /* For non-methods, the list of overloaded function symbols. */
2425 struct symbol **oload_syms = NULL;
2426 /* Number of overloaded instances being considered. */
2427 int num_fns = 0;
2428 struct type *basetype = NULL;
2429 int boffset;
2430
2431 struct cleanup *all_cleanups = make_cleanup (null_cleanup, NULL);
2432
2433 const char *obj_type_name = NULL;
2434 const char *func_name = NULL;
2435 enum oload_classification match_quality;
2436 enum oload_classification method_match_quality = INCOMPATIBLE;
2437 enum oload_classification func_match_quality = INCOMPATIBLE;
2438
2439 /* Get the list of overloaded methods or functions. */
2440 if (method == METHOD || method == BOTH)
2441 {
2442 gdb_assert (obj);
2443
2444 /* OBJ may be a pointer value rather than the object itself. */
2445 obj = coerce_ref (obj);
2446 while (TYPE_CODE (check_typedef (value_type (obj))) == TYPE_CODE_PTR)
2447 obj = coerce_ref (value_ind (obj));
2448 obj_type_name = TYPE_NAME (value_type (obj));
2449
2450 /* First check whether this is a data member, e.g. a pointer to
2451 a function. */
2452 if (TYPE_CODE (check_typedef (value_type (obj))) == TYPE_CODE_STRUCT)
2453 {
2454 *valp = search_struct_field (name, obj, 0,
2455 check_typedef (value_type (obj)), 0);
2456 if (*valp)
2457 {
2458 *staticp = 1;
2459 do_cleanups (all_cleanups);
2460 return 0;
2461 }
2462 }
2463
2464 /* Retrieve the list of methods with the name NAME. */
2465 fns_ptr = value_find_oload_method_list (&temp, name,
2466 0, &num_fns,
2467 &basetype, &boffset);
2468 /* If this is a method only search, and no methods were found
2469 the search has faild. */
2470 if (method == METHOD && (!fns_ptr || !num_fns))
2471 error (_("Couldn't find method %s%s%s"),
2472 obj_type_name,
2473 (obj_type_name && *obj_type_name) ? "::" : "",
2474 name);
2475 /* If we are dealing with stub method types, they should have
2476 been resolved by find_method_list via
2477 value_find_oload_method_list above. */
2478 if (fns_ptr)
2479 {
2480 gdb_assert (TYPE_DOMAIN_TYPE (fns_ptr[0].type) != NULL);
2481 method_oload_champ = find_oload_champ (args, nargs,
2482 num_fns, fns_ptr,
2483 NULL, &method_badness);
2484
2485 method_match_quality =
2486 classify_oload_match (method_badness, nargs,
2487 oload_method_static (method, fns_ptr,
2488 method_oload_champ));
2489
2490 make_cleanup (xfree, method_badness);
2491 }
2492
2493 }
2494
2495 if (method == NON_METHOD || method == BOTH)
2496 {
2497 const char *qualified_name = NULL;
2498
2499 /* If the overload match is being search for both as a method
2500 and non member function, the first argument must now be
2501 dereferenced. */
2502 if (method == BOTH)
2503 args[0] = value_ind (args[0]);
2504
2505 if (fsym)
2506 {
2507 qualified_name = SYMBOL_NATURAL_NAME (fsym);
2508
2509 /* If we have a function with a C++ name, try to extract just
2510 the function part. Do not try this for non-functions (e.g.
2511 function pointers). */
2512 if (qualified_name
2513 && TYPE_CODE (check_typedef (SYMBOL_TYPE (fsym)))
2514 == TYPE_CODE_FUNC)
2515 {
2516 char *temp;
2517
2518 temp = cp_func_name (qualified_name);
2519
2520 /* If cp_func_name did not remove anything, the name of the
2521 symbol did not include scope or argument types - it was
2522 probably a C-style function. */
2523 if (temp)
2524 {
2525 make_cleanup (xfree, temp);
2526 if (strcmp (temp, qualified_name) == 0)
2527 func_name = NULL;
2528 else
2529 func_name = temp;
2530 }
2531 }
2532 }
2533 else
2534 {
2535 func_name = name;
2536 qualified_name = name;
2537 }
2538
2539 /* If there was no C++ name, this must be a C-style function or
2540 not a function at all. Just return the same symbol. Do the
2541 same if cp_func_name fails for some reason. */
2542 if (func_name == NULL)
2543 {
2544 *symp = fsym;
2545 do_cleanups (all_cleanups);
2546 return 0;
2547 }
2548
2549 func_oload_champ = find_oload_champ_namespace (args, nargs,
2550 func_name,
2551 qualified_name,
2552 &oload_syms,
2553 &func_badness,
2554 no_adl);
2555
2556 if (func_oload_champ >= 0)
2557 func_match_quality = classify_oload_match (func_badness, nargs, 0);
2558
2559 make_cleanup (xfree, oload_syms);
2560 make_cleanup (xfree, func_badness);
2561 }
2562
2563 /* Did we find a match ? */
2564 if (method_oload_champ == -1 && func_oload_champ == -1)
2565 throw_error (NOT_FOUND_ERROR,
2566 _("No symbol \"%s\" in current context."),
2567 name);
2568
2569 /* If we have found both a method match and a function
2570 match, find out which one is better, and calculate match
2571 quality. */
2572 if (method_oload_champ >= 0 && func_oload_champ >= 0)
2573 {
2574 switch (compare_badness (func_badness, method_badness))
2575 {
2576 case 0: /* Top two contenders are equally good. */
2577 /* FIXME: GDB does not support the general ambiguous case.
2578 All candidates should be collected and presented the
2579 user. */
2580 error (_("Ambiguous overload resolution"));
2581 break;
2582 case 1: /* Incomparable top contenders. */
2583 /* This is an error incompatible candidates
2584 should not have been proposed. */
2585 error (_("Internal error: incompatible "
2586 "overload candidates proposed"));
2587 break;
2588 case 2: /* Function champion. */
2589 method_oload_champ = -1;
2590 match_quality = func_match_quality;
2591 break;
2592 case 3: /* Method champion. */
2593 func_oload_champ = -1;
2594 match_quality = method_match_quality;
2595 break;
2596 default:
2597 error (_("Internal error: unexpected overload comparison result"));
2598 break;
2599 }
2600 }
2601 else
2602 {
2603 /* We have either a method match or a function match. */
2604 if (method_oload_champ >= 0)
2605 match_quality = method_match_quality;
2606 else
2607 match_quality = func_match_quality;
2608 }
2609
2610 if (match_quality == INCOMPATIBLE)
2611 {
2612 if (method == METHOD)
2613 error (_("Cannot resolve method %s%s%s to any overloaded instance"),
2614 obj_type_name,
2615 (obj_type_name && *obj_type_name) ? "::" : "",
2616 name);
2617 else
2618 error (_("Cannot resolve function %s to any overloaded instance"),
2619 func_name);
2620 }
2621 else if (match_quality == NON_STANDARD)
2622 {
2623 if (method == METHOD)
2624 warning (_("Using non-standard conversion to match "
2625 "method %s%s%s to supplied arguments"),
2626 obj_type_name,
2627 (obj_type_name && *obj_type_name) ? "::" : "",
2628 name);
2629 else
2630 warning (_("Using non-standard conversion to match "
2631 "function %s to supplied arguments"),
2632 func_name);
2633 }
2634
2635 if (staticp != NULL)
2636 *staticp = oload_method_static (method, fns_ptr, method_oload_champ);
2637
2638 if (method_oload_champ >= 0)
2639 {
2640 if (TYPE_FN_FIELD_VIRTUAL_P (fns_ptr, method_oload_champ))
2641 *valp = value_virtual_fn_field (&temp, fns_ptr, method_oload_champ,
2642 basetype, boffset);
2643 else
2644 *valp = value_fn_field (&temp, fns_ptr, method_oload_champ,
2645 basetype, boffset);
2646 }
2647 else
2648 *symp = oload_syms[func_oload_champ];
2649
2650 if (objp)
2651 {
2652 struct type *temp_type = check_typedef (value_type (temp));
2653 struct type *objtype = check_typedef (obj_type);
2654
2655 if (TYPE_CODE (temp_type) != TYPE_CODE_PTR
2656 && (TYPE_CODE (objtype) == TYPE_CODE_PTR
2657 || TYPE_CODE (objtype) == TYPE_CODE_REF))
2658 {
2659 temp = value_addr (temp);
2660 }
2661 *objp = temp;
2662 }
2663
2664 do_cleanups (all_cleanups);
2665
2666 switch (match_quality)
2667 {
2668 case INCOMPATIBLE:
2669 return 100;
2670 case NON_STANDARD:
2671 return 10;
2672 default: /* STANDARD */
2673 return 0;
2674 }
2675 }
2676
2677 /* Find the best overload match, searching for FUNC_NAME in namespaces
2678 contained in QUALIFIED_NAME until it either finds a good match or
2679 runs out of namespaces. It stores the overloaded functions in
2680 *OLOAD_SYMS, and the badness vector in *OLOAD_CHAMP_BV. The
2681 calling function is responsible for freeing *OLOAD_SYMS and
2682 *OLOAD_CHAMP_BV. If NO_ADL, argument dependent lookup is not
2683 performned. */
2684
2685 static int
2686 find_oload_champ_namespace (struct value **args, int nargs,
2687 const char *func_name,
2688 const char *qualified_name,
2689 struct symbol ***oload_syms,
2690 struct badness_vector **oload_champ_bv,
2691 const int no_adl)
2692 {
2693 int oload_champ;
2694
2695 find_oload_champ_namespace_loop (args, nargs,
2696 func_name,
2697 qualified_name, 0,
2698 oload_syms, oload_champ_bv,
2699 &oload_champ,
2700 no_adl);
2701
2702 return oload_champ;
2703 }
2704
2705 /* Helper function for find_oload_champ_namespace; NAMESPACE_LEN is
2706 how deep we've looked for namespaces, and the champ is stored in
2707 OLOAD_CHAMP. The return value is 1 if the champ is a good one, 0
2708 if it isn't. Other arguments are the same as in
2709 find_oload_champ_namespace
2710
2711 It is the caller's responsibility to free *OLOAD_SYMS and
2712 *OLOAD_CHAMP_BV. */
2713
2714 static int
2715 find_oload_champ_namespace_loop (struct value **args, int nargs,
2716 const char *func_name,
2717 const char *qualified_name,
2718 int namespace_len,
2719 struct symbol ***oload_syms,
2720 struct badness_vector **oload_champ_bv,
2721 int *oload_champ,
2722 const int no_adl)
2723 {
2724 int next_namespace_len = namespace_len;
2725 int searched_deeper = 0;
2726 int num_fns = 0;
2727 struct cleanup *old_cleanups;
2728 int new_oload_champ;
2729 struct symbol **new_oload_syms;
2730 struct badness_vector *new_oload_champ_bv;
2731 char *new_namespace;
2732
2733 if (next_namespace_len != 0)
2734 {
2735 gdb_assert (qualified_name[next_namespace_len] == ':');
2736 next_namespace_len += 2;
2737 }
2738 next_namespace_len +=
2739 cp_find_first_component (qualified_name + next_namespace_len);
2740
2741 /* Initialize these to values that can safely be xfree'd. */
2742 *oload_syms = NULL;
2743 *oload_champ_bv = NULL;
2744
2745 /* First, see if we have a deeper namespace we can search in.
2746 If we get a good match there, use it. */
2747
2748 if (qualified_name[next_namespace_len] == ':')
2749 {
2750 searched_deeper = 1;
2751
2752 if (find_oload_champ_namespace_loop (args, nargs,
2753 func_name, qualified_name,
2754 next_namespace_len,
2755 oload_syms, oload_champ_bv,
2756 oload_champ, no_adl))
2757 {
2758 return 1;
2759 }
2760 };
2761
2762 /* If we reach here, either we're in the deepest namespace or we
2763 didn't find a good match in a deeper namespace. But, in the
2764 latter case, we still have a bad match in a deeper namespace;
2765 note that we might not find any match at all in the current
2766 namespace. (There's always a match in the deepest namespace,
2767 because this overload mechanism only gets called if there's a
2768 function symbol to start off with.) */
2769
2770 old_cleanups = make_cleanup (xfree, *oload_syms);
2771 make_cleanup (xfree, *oload_champ_bv);
2772 new_namespace = alloca (namespace_len + 1);
2773 strncpy (new_namespace, qualified_name, namespace_len);
2774 new_namespace[namespace_len] = '\0';
2775 new_oload_syms = make_symbol_overload_list (func_name,
2776 new_namespace);
2777
2778 /* If we have reached the deepest level perform argument
2779 determined lookup. */
2780 if (!searched_deeper && !no_adl)
2781 {
2782 int ix;
2783 struct type **arg_types;
2784
2785 /* Prepare list of argument types for overload resolution. */
2786 arg_types = (struct type **)
2787 alloca (nargs * (sizeof (struct type *)));
2788 for (ix = 0; ix < nargs; ix++)
2789 arg_types[ix] = value_type (args[ix]);
2790 make_symbol_overload_list_adl (arg_types, nargs, func_name);
2791 }
2792
2793 while (new_oload_syms[num_fns])
2794 ++num_fns;
2795
2796 new_oload_champ = find_oload_champ (args, nargs, num_fns,
2797 NULL, new_oload_syms,
2798 &new_oload_champ_bv);
2799
2800 /* Case 1: We found a good match. Free earlier matches (if any),
2801 and return it. Case 2: We didn't find a good match, but we're
2802 not the deepest function. Then go with the bad match that the
2803 deeper function found. Case 3: We found a bad match, and we're
2804 the deepest function. Then return what we found, even though
2805 it's a bad match. */
2806
2807 if (new_oload_champ != -1
2808 && classify_oload_match (new_oload_champ_bv, nargs, 0) == STANDARD)
2809 {
2810 *oload_syms = new_oload_syms;
2811 *oload_champ = new_oload_champ;
2812 *oload_champ_bv = new_oload_champ_bv;
2813 do_cleanups (old_cleanups);
2814 return 1;
2815 }
2816 else if (searched_deeper)
2817 {
2818 xfree (new_oload_syms);
2819 xfree (new_oload_champ_bv);
2820 discard_cleanups (old_cleanups);
2821 return 0;
2822 }
2823 else
2824 {
2825 *oload_syms = new_oload_syms;
2826 *oload_champ = new_oload_champ;
2827 *oload_champ_bv = new_oload_champ_bv;
2828 do_cleanups (old_cleanups);
2829 return 0;
2830 }
2831 }
2832
2833 /* Look for a function to take NARGS args of ARGS. Find
2834 the best match from among the overloaded methods or functions
2835 given by FNS_PTR or OLOAD_SYMS, respectively. One, and only one of
2836 FNS_PTR and OLOAD_SYMS can be non-NULL. The number of
2837 methods/functions in the non-NULL list is given by NUM_FNS.
2838 Return the index of the best match; store an indication of the
2839 quality of the match in OLOAD_CHAMP_BV.
2840
2841 It is the caller's responsibility to free *OLOAD_CHAMP_BV. */
2842
2843 static int
2844 find_oload_champ (struct value **args, int nargs,
2845 int num_fns, struct fn_field *fns_ptr,
2846 struct symbol **oload_syms,
2847 struct badness_vector **oload_champ_bv)
2848 {
2849 int ix;
2850 /* A measure of how good an overloaded instance is. */
2851 struct badness_vector *bv;
2852 /* Index of best overloaded function. */
2853 int oload_champ = -1;
2854 /* Current ambiguity state for overload resolution. */
2855 int oload_ambiguous = 0;
2856 /* 0 => no ambiguity, 1 => two good funcs, 2 => incomparable funcs. */
2857
2858 /* A champion can be found among methods alone, or among functions
2859 alone, but not both. */
2860 gdb_assert ((fns_ptr != NULL) + (oload_syms != NULL) == 1);
2861
2862 *oload_champ_bv = NULL;
2863
2864 /* Consider each candidate in turn. */
2865 for (ix = 0; ix < num_fns; ix++)
2866 {
2867 int jj;
2868 int static_offset;
2869 int nparms;
2870 struct type **parm_types;
2871
2872 if (fns_ptr != NULL)
2873 {
2874 nparms = TYPE_NFIELDS (TYPE_FN_FIELD_TYPE (fns_ptr, ix));
2875 static_offset = oload_method_static (1, fns_ptr, ix);
2876 }
2877 else
2878 {
2879 /* If it's not a method, this is the proper place. */
2880 nparms = TYPE_NFIELDS (SYMBOL_TYPE (oload_syms[ix]));
2881 static_offset = 0;
2882 }
2883
2884 /* Prepare array of parameter types. */
2885 parm_types = (struct type **)
2886 xmalloc (nparms * (sizeof (struct type *)));
2887 for (jj = 0; jj < nparms; jj++)
2888 parm_types[jj] = (fns_ptr != NULL
2889 ? (TYPE_FN_FIELD_ARGS (fns_ptr, ix)[jj].type)
2890 : TYPE_FIELD_TYPE (SYMBOL_TYPE (oload_syms[ix]),
2891 jj));
2892
2893 /* Compare parameter types to supplied argument types. Skip
2894 THIS for static methods. */
2895 bv = rank_function (parm_types, nparms,
2896 args + static_offset,
2897 nargs - static_offset);
2898
2899 if (!*oload_champ_bv)
2900 {
2901 *oload_champ_bv = bv;
2902 oload_champ = 0;
2903 }
2904 else /* See whether current candidate is better or worse than
2905 previous best. */
2906 switch (compare_badness (bv, *oload_champ_bv))
2907 {
2908 case 0: /* Top two contenders are equally good. */
2909 oload_ambiguous = 1;
2910 break;
2911 case 1: /* Incomparable top contenders. */
2912 oload_ambiguous = 2;
2913 break;
2914 case 2: /* New champion, record details. */
2915 *oload_champ_bv = bv;
2916 oload_ambiguous = 0;
2917 oload_champ = ix;
2918 break;
2919 case 3:
2920 default:
2921 break;
2922 }
2923 xfree (parm_types);
2924 if (overload_debug)
2925 {
2926 if (fns_ptr)
2927 fprintf_filtered (gdb_stderr,
2928 "Overloaded method instance %s, # of parms %d\n",
2929 fns_ptr[ix].physname, nparms);
2930 else
2931 fprintf_filtered (gdb_stderr,
2932 "Overloaded function instance "
2933 "%s # of parms %d\n",
2934 SYMBOL_DEMANGLED_NAME (oload_syms[ix]),
2935 nparms);
2936 for (jj = 0; jj < nargs - static_offset; jj++)
2937 fprintf_filtered (gdb_stderr,
2938 "...Badness @ %d : %d\n",
2939 jj, bv->rank[jj].rank);
2940 fprintf_filtered (gdb_stderr, "Overload resolution "
2941 "champion is %d, ambiguous? %d\n",
2942 oload_champ, oload_ambiguous);
2943 }
2944 }
2945
2946 return oload_champ;
2947 }
2948
2949 /* Return 1 if we're looking at a static method, 0 if we're looking at
2950 a non-static method or a function that isn't a method. */
2951
2952 static int
2953 oload_method_static (int method, struct fn_field *fns_ptr, int index)
2954 {
2955 if (method && fns_ptr && index >= 0
2956 && TYPE_FN_FIELD_STATIC_P (fns_ptr, index))
2957 return 1;
2958 else
2959 return 0;
2960 }
2961
2962 /* Check how good an overload match OLOAD_CHAMP_BV represents. */
2963
2964 static enum oload_classification
2965 classify_oload_match (struct badness_vector *oload_champ_bv,
2966 int nargs,
2967 int static_offset)
2968 {
2969 int ix;
2970 enum oload_classification worst = STANDARD;
2971
2972 for (ix = 1; ix <= nargs - static_offset; ix++)
2973 {
2974 /* If this conversion is as bad as INCOMPATIBLE_TYPE_BADNESS
2975 or worse return INCOMPATIBLE. */
2976 if (compare_ranks (oload_champ_bv->rank[ix],
2977 INCOMPATIBLE_TYPE_BADNESS) <= 0)
2978 return INCOMPATIBLE; /* Truly mismatched types. */
2979 /* Otherwise If this conversion is as bad as
2980 NS_POINTER_CONVERSION_BADNESS or worse return NON_STANDARD. */
2981 else if (compare_ranks (oload_champ_bv->rank[ix],
2982 NS_POINTER_CONVERSION_BADNESS) <= 0)
2983 worst = NON_STANDARD; /* Non-standard type conversions
2984 needed. */
2985 }
2986
2987 /* If no INCOMPATIBLE classification was found, return the worst one
2988 that was found (if any). */
2989 return worst;
2990 }
2991
2992 /* C++: return 1 is NAME is a legitimate name for the destructor of
2993 type TYPE. If TYPE does not have a destructor, or if NAME is
2994 inappropriate for TYPE, an error is signaled. Parameter TYPE should not yet
2995 have CHECK_TYPEDEF applied, this function will apply it itself. */
2996
2997 int
2998 destructor_name_p (const char *name, struct type *type)
2999 {
3000 if (name[0] == '~')
3001 {
3002 const char *dname = type_name_no_tag_or_error (type);
3003 const char *cp = strchr (dname, '<');
3004 unsigned int len;
3005
3006 /* Do not compare the template part for template classes. */
3007 if (cp == NULL)
3008 len = strlen (dname);
3009 else
3010 len = cp - dname;
3011 if (strlen (name + 1) != len || strncmp (dname, name + 1, len) != 0)
3012 error (_("name of destructor must equal name of class"));
3013 else
3014 return 1;
3015 }
3016 return 0;
3017 }
3018
3019 /* C++: Given an aggregate type CURTYPE, and a member name NAME,
3020 return the appropriate member (or the address of the member, if
3021 WANT_ADDRESS). This function is used to resolve user expressions
3022 of the form "DOMAIN::NAME". For more details on what happens, see
3023 the comment before value_struct_elt_for_reference. */
3024
3025 struct value *
3026 value_aggregate_elt (struct type *curtype, char *name,
3027 struct type *expect_type, int want_address,
3028 enum noside noside)
3029 {
3030 switch (TYPE_CODE (curtype))
3031 {
3032 case TYPE_CODE_STRUCT:
3033 case TYPE_CODE_UNION:
3034 return value_struct_elt_for_reference (curtype, 0, curtype,
3035 name, expect_type,
3036 want_address, noside);
3037 case TYPE_CODE_NAMESPACE:
3038 return value_namespace_elt (curtype, name,
3039 want_address, noside);
3040 default:
3041 internal_error (__FILE__, __LINE__,
3042 _("non-aggregate type in value_aggregate_elt"));
3043 }
3044 }
3045
3046 /* Compares the two method/function types T1 and T2 for "equality"
3047 with respect to the methods' parameters. If the types of the
3048 two parameter lists are the same, returns 1; 0 otherwise. This
3049 comparison may ignore any artificial parameters in T1 if
3050 SKIP_ARTIFICIAL is non-zero. This function will ALWAYS skip
3051 the first artificial parameter in T1, assumed to be a 'this' pointer.
3052
3053 The type T2 is expected to have come from make_params (in eval.c). */
3054
3055 static int
3056 compare_parameters (struct type *t1, struct type *t2, int skip_artificial)
3057 {
3058 int start = 0;
3059
3060 if (TYPE_NFIELDS (t1) > 0 && TYPE_FIELD_ARTIFICIAL (t1, 0))
3061 ++start;
3062
3063 /* If skipping artificial fields, find the first real field
3064 in T1. */
3065 if (skip_artificial)
3066 {
3067 while (start < TYPE_NFIELDS (t1)
3068 && TYPE_FIELD_ARTIFICIAL (t1, start))
3069 ++start;
3070 }
3071
3072 /* Now compare parameters. */
3073
3074 /* Special case: a method taking void. T1 will contain no
3075 non-artificial fields, and T2 will contain TYPE_CODE_VOID. */
3076 if ((TYPE_NFIELDS (t1) - start) == 0 && TYPE_NFIELDS (t2) == 1
3077 && TYPE_CODE (TYPE_FIELD_TYPE (t2, 0)) == TYPE_CODE_VOID)
3078 return 1;
3079
3080 if ((TYPE_NFIELDS (t1) - start) == TYPE_NFIELDS (t2))
3081 {
3082 int i;
3083
3084 for (i = 0; i < TYPE_NFIELDS (t2); ++i)
3085 {
3086 if (compare_ranks (rank_one_type (TYPE_FIELD_TYPE (t1, start + i),
3087 TYPE_FIELD_TYPE (t2, i), NULL),
3088 EXACT_MATCH_BADNESS) != 0)
3089 return 0;
3090 }
3091
3092 return 1;
3093 }
3094
3095 return 0;
3096 }
3097
3098 /* C++: Given an aggregate type CURTYPE, and a member name NAME,
3099 return the address of this member as a "pointer to member" type.
3100 If INTYPE is non-null, then it will be the type of the member we
3101 are looking for. This will help us resolve "pointers to member
3102 functions". This function is used to resolve user expressions of
3103 the form "DOMAIN::NAME". */
3104
3105 static struct value *
3106 value_struct_elt_for_reference (struct type *domain, int offset,
3107 struct type *curtype, char *name,
3108 struct type *intype,
3109 int want_address,
3110 enum noside noside)
3111 {
3112 struct type *t = curtype;
3113 int i;
3114 struct value *v, *result;
3115
3116 if (TYPE_CODE (t) != TYPE_CODE_STRUCT
3117 && TYPE_CODE (t) != TYPE_CODE_UNION)
3118 error (_("Internal error: non-aggregate type "
3119 "to value_struct_elt_for_reference"));
3120
3121 for (i = TYPE_NFIELDS (t) - 1; i >= TYPE_N_BASECLASSES (t); i--)
3122 {
3123 const char *t_field_name = TYPE_FIELD_NAME (t, i);
3124
3125 if (t_field_name && strcmp (t_field_name, name) == 0)
3126 {
3127 if (field_is_static (&TYPE_FIELD (t, i)))
3128 {
3129 v = value_static_field (t, i);
3130 if (want_address)
3131 v = value_addr (v);
3132 return v;
3133 }
3134 if (TYPE_FIELD_PACKED (t, i))
3135 error (_("pointers to bitfield members not allowed"));
3136
3137 if (want_address)
3138 return value_from_longest
3139 (lookup_memberptr_type (TYPE_FIELD_TYPE (t, i), domain),
3140 offset + (LONGEST) (TYPE_FIELD_BITPOS (t, i) >> 3));
3141 else if (noside != EVAL_NORMAL)
3142 return allocate_value (TYPE_FIELD_TYPE (t, i));
3143 else
3144 {
3145 /* Try to evaluate NAME as a qualified name with implicit
3146 this pointer. In this case, attempt to return the
3147 equivalent to `this->*(&TYPE::NAME)'. */
3148 v = value_of_this_silent (current_language);
3149 if (v != NULL)
3150 {
3151 struct value *ptr;
3152 long mem_offset;
3153 struct type *type, *tmp;
3154
3155 ptr = value_aggregate_elt (domain, name, NULL, 1, noside);
3156 type = check_typedef (value_type (ptr));
3157 gdb_assert (type != NULL
3158 && TYPE_CODE (type) == TYPE_CODE_MEMBERPTR);
3159 tmp = lookup_pointer_type (TYPE_DOMAIN_TYPE (type));
3160 v = value_cast_pointers (tmp, v, 1);
3161 mem_offset = value_as_long (ptr);
3162 tmp = lookup_pointer_type (TYPE_TARGET_TYPE (type));
3163 result = value_from_pointer (tmp,
3164 value_as_long (v) + mem_offset);
3165 return value_ind (result);
3166 }
3167
3168 error (_("Cannot reference non-static field \"%s\""), name);
3169 }
3170 }
3171 }
3172
3173 /* C++: If it was not found as a data field, then try to return it
3174 as a pointer to a method. */
3175
3176 /* Perform all necessary dereferencing. */
3177 while (intype && TYPE_CODE (intype) == TYPE_CODE_PTR)
3178 intype = TYPE_TARGET_TYPE (intype);
3179
3180 for (i = TYPE_NFN_FIELDS (t) - 1; i >= 0; --i)
3181 {
3182 const char *t_field_name = TYPE_FN_FIELDLIST_NAME (t, i);
3183 char dem_opname[64];
3184
3185 if (strncmp (t_field_name, "__", 2) == 0
3186 || strncmp (t_field_name, "op", 2) == 0
3187 || strncmp (t_field_name, "type", 4) == 0)
3188 {
3189 if (cplus_demangle_opname (t_field_name,
3190 dem_opname, DMGL_ANSI))
3191 t_field_name = dem_opname;
3192 else if (cplus_demangle_opname (t_field_name,
3193 dem_opname, 0))
3194 t_field_name = dem_opname;
3195 }
3196 if (t_field_name && strcmp (t_field_name, name) == 0)
3197 {
3198 int j;
3199 int len = TYPE_FN_FIELDLIST_LENGTH (t, i);
3200 struct fn_field *f = TYPE_FN_FIELDLIST1 (t, i);
3201
3202 check_stub_method_group (t, i);
3203
3204 if (intype)
3205 {
3206 for (j = 0; j < len; ++j)
3207 {
3208 if (compare_parameters (TYPE_FN_FIELD_TYPE (f, j), intype, 0)
3209 || compare_parameters (TYPE_FN_FIELD_TYPE (f, j),
3210 intype, 1))
3211 break;
3212 }
3213
3214 if (j == len)
3215 error (_("no member function matches "
3216 "that type instantiation"));
3217 }
3218 else
3219 {
3220 int ii;
3221
3222 j = -1;
3223 for (ii = 0; ii < len; ++ii)
3224 {
3225 /* Skip artificial methods. This is necessary if,
3226 for example, the user wants to "print
3227 subclass::subclass" with only one user-defined
3228 constructor. There is no ambiguity in this case.
3229 We are careful here to allow artificial methods
3230 if they are the unique result. */
3231 if (TYPE_FN_FIELD_ARTIFICIAL (f, ii))
3232 {
3233 if (j == -1)
3234 j = ii;
3235 continue;
3236 }
3237
3238 /* Desired method is ambiguous if more than one
3239 method is defined. */
3240 if (j != -1 && !TYPE_FN_FIELD_ARTIFICIAL (f, j))
3241 error (_("non-unique member `%s' requires "
3242 "type instantiation"), name);
3243
3244 j = ii;
3245 }
3246
3247 if (j == -1)
3248 error (_("no matching member function"));
3249 }
3250
3251 if (TYPE_FN_FIELD_STATIC_P (f, j))
3252 {
3253 struct symbol *s =
3254 lookup_symbol (TYPE_FN_FIELD_PHYSNAME (f, j),
3255 0, VAR_DOMAIN, 0);
3256
3257 if (s == NULL)
3258 return NULL;
3259
3260 if (want_address)
3261 return value_addr (read_var_value (s, 0));
3262 else
3263 return read_var_value (s, 0);
3264 }
3265
3266 if (TYPE_FN_FIELD_VIRTUAL_P (f, j))
3267 {
3268 if (want_address)
3269 {
3270 result = allocate_value
3271 (lookup_methodptr_type (TYPE_FN_FIELD_TYPE (f, j)));
3272 cplus_make_method_ptr (value_type (result),
3273 value_contents_writeable (result),
3274 TYPE_FN_FIELD_VOFFSET (f, j), 1);
3275 }
3276 else if (noside == EVAL_AVOID_SIDE_EFFECTS)
3277 return allocate_value (TYPE_FN_FIELD_TYPE (f, j));
3278 else
3279 error (_("Cannot reference virtual member function \"%s\""),
3280 name);
3281 }
3282 else
3283 {
3284 struct symbol *s =
3285 lookup_symbol (TYPE_FN_FIELD_PHYSNAME (f, j),
3286 0, VAR_DOMAIN, 0);
3287
3288 if (s == NULL)
3289 return NULL;
3290
3291 v = read_var_value (s, 0);
3292 if (!want_address)
3293 result = v;
3294 else
3295 {
3296 result = allocate_value (lookup_methodptr_type (TYPE_FN_FIELD_TYPE (f, j)));
3297 cplus_make_method_ptr (value_type (result),
3298 value_contents_writeable (result),
3299 value_address (v), 0);
3300 }
3301 }
3302 return result;
3303 }
3304 }
3305 for (i = TYPE_N_BASECLASSES (t) - 1; i >= 0; i--)
3306 {
3307 struct value *v;
3308 int base_offset;
3309
3310 if (BASETYPE_VIA_VIRTUAL (t, i))
3311 base_offset = 0;
3312 else
3313 base_offset = TYPE_BASECLASS_BITPOS (t, i) / 8;
3314 v = value_struct_elt_for_reference (domain,
3315 offset + base_offset,
3316 TYPE_BASECLASS (t, i),
3317 name, intype,
3318 want_address, noside);
3319 if (v)
3320 return v;
3321 }
3322
3323 /* As a last chance, pretend that CURTYPE is a namespace, and look
3324 it up that way; this (frequently) works for types nested inside
3325 classes. */
3326
3327 return value_maybe_namespace_elt (curtype, name,
3328 want_address, noside);
3329 }
3330
3331 /* C++: Return the member NAME of the namespace given by the type
3332 CURTYPE. */
3333
3334 static struct value *
3335 value_namespace_elt (const struct type *curtype,
3336 char *name, int want_address,
3337 enum noside noside)
3338 {
3339 struct value *retval = value_maybe_namespace_elt (curtype, name,
3340 want_address,
3341 noside);
3342
3343 if (retval == NULL)
3344 error (_("No symbol \"%s\" in namespace \"%s\"."),
3345 name, TYPE_TAG_NAME (curtype));
3346
3347 return retval;
3348 }
3349
3350 /* A helper function used by value_namespace_elt and
3351 value_struct_elt_for_reference. It looks up NAME inside the
3352 context CURTYPE; this works if CURTYPE is a namespace or if CURTYPE
3353 is a class and NAME refers to a type in CURTYPE itself (as opposed
3354 to, say, some base class of CURTYPE). */
3355
3356 static struct value *
3357 value_maybe_namespace_elt (const struct type *curtype,
3358 char *name, int want_address,
3359 enum noside noside)
3360 {
3361 const char *namespace_name = TYPE_TAG_NAME (curtype);
3362 struct symbol *sym;
3363 struct value *result;
3364
3365 sym = cp_lookup_symbol_namespace (namespace_name, name,
3366 get_selected_block (0), VAR_DOMAIN);
3367
3368 if (sym == NULL)
3369 {
3370 char *concatenated_name = alloca (strlen (namespace_name) + 2
3371 + strlen (name) + 1);
3372
3373 sprintf (concatenated_name, "%s::%s", namespace_name, name);
3374 sym = lookup_static_symbol_aux (concatenated_name, VAR_DOMAIN);
3375 }
3376
3377 if (sym == NULL)
3378 return NULL;
3379 else if ((noside == EVAL_AVOID_SIDE_EFFECTS)
3380 && (SYMBOL_CLASS (sym) == LOC_TYPEDEF))
3381 result = allocate_value (SYMBOL_TYPE (sym));
3382 else
3383 result = value_of_variable (sym, get_selected_block (0));
3384
3385 if (result && want_address)
3386 result = value_addr (result);
3387
3388 return result;
3389 }
3390
3391 /* Given a pointer or a reference value V, find its real (RTTI) type.
3392
3393 Other parameters FULL, TOP, USING_ENC as with value_rtti_type()
3394 and refer to the values computed for the object pointed to. */
3395
3396 struct type *
3397 value_rtti_indirect_type (struct value *v, int *full,
3398 int *top, int *using_enc)
3399 {
3400 struct value *target;
3401 struct type *type, *real_type, *target_type;
3402
3403 type = value_type (v);
3404 type = check_typedef (type);
3405 if (TYPE_CODE (type) == TYPE_CODE_REF)
3406 target = coerce_ref (v);
3407 else if (TYPE_CODE (type) == TYPE_CODE_PTR)
3408 target = value_ind (v);
3409 else
3410 return NULL;
3411
3412 real_type = value_rtti_type (target, full, top, using_enc);
3413
3414 if (real_type)
3415 {
3416 /* Copy qualifiers to the referenced object. */
3417 target_type = value_type (target);
3418 real_type = make_cv_type (TYPE_CONST (target_type),
3419 TYPE_VOLATILE (target_type), real_type, NULL);
3420 if (TYPE_CODE (type) == TYPE_CODE_REF)
3421 real_type = lookup_reference_type (real_type);
3422 else if (TYPE_CODE (type) == TYPE_CODE_PTR)
3423 real_type = lookup_pointer_type (real_type);
3424 else
3425 internal_error (__FILE__, __LINE__, _("Unexpected value type."));
3426
3427 /* Copy qualifiers to the pointer/reference. */
3428 real_type = make_cv_type (TYPE_CONST (type), TYPE_VOLATILE (type),
3429 real_type, NULL);
3430 }
3431
3432 return real_type;
3433 }
3434
3435 /* Given a value pointed to by ARGP, check its real run-time type, and
3436 if that is different from the enclosing type, create a new value
3437 using the real run-time type as the enclosing type (and of the same
3438 type as ARGP) and return it, with the embedded offset adjusted to
3439 be the correct offset to the enclosed object. RTYPE is the type,
3440 and XFULL, XTOP, and XUSING_ENC are the other parameters, computed
3441 by value_rtti_type(). If these are available, they can be supplied
3442 and a second call to value_rtti_type() is avoided. (Pass RTYPE ==
3443 NULL if they're not available. */
3444
3445 struct value *
3446 value_full_object (struct value *argp,
3447 struct type *rtype,
3448 int xfull, int xtop,
3449 int xusing_enc)
3450 {
3451 struct type *real_type;
3452 int full = 0;
3453 int top = -1;
3454 int using_enc = 0;
3455 struct value *new_val;
3456
3457 if (rtype)
3458 {
3459 real_type = rtype;
3460 full = xfull;
3461 top = xtop;
3462 using_enc = xusing_enc;
3463 }
3464 else
3465 real_type = value_rtti_type (argp, &full, &top, &using_enc);
3466
3467 /* If no RTTI data, or if object is already complete, do nothing. */
3468 if (!real_type || real_type == value_enclosing_type (argp))
3469 return argp;
3470
3471 /* In a destructor we might see a real type that is a superclass of
3472 the object's type. In this case it is better to leave the object
3473 as-is. */
3474 if (full
3475 && TYPE_LENGTH (real_type) < TYPE_LENGTH (value_enclosing_type (argp)))
3476 return argp;
3477
3478 /* If we have the full object, but for some reason the enclosing
3479 type is wrong, set it. */
3480 /* pai: FIXME -- sounds iffy */
3481 if (full)
3482 {
3483 argp = value_copy (argp);
3484 set_value_enclosing_type (argp, real_type);
3485 return argp;
3486 }
3487
3488 /* Check if object is in memory. */
3489 if (VALUE_LVAL (argp) != lval_memory)
3490 {
3491 warning (_("Couldn't retrieve complete object of RTTI "
3492 "type %s; object may be in register(s)."),
3493 TYPE_NAME (real_type));
3494
3495 return argp;
3496 }
3497
3498 /* All other cases -- retrieve the complete object. */
3499 /* Go back by the computed top_offset from the beginning of the
3500 object, adjusting for the embedded offset of argp if that's what
3501 value_rtti_type used for its computation. */
3502 new_val = value_at_lazy (real_type, value_address (argp) - top +
3503 (using_enc ? 0 : value_embedded_offset (argp)));
3504 deprecated_set_value_type (new_val, value_type (argp));
3505 set_value_embedded_offset (new_val, (using_enc
3506 ? top + value_embedded_offset (argp)
3507 : top));
3508 return new_val;
3509 }
3510
3511
3512 /* Return the value of the local variable, if one exists. Throw error
3513 otherwise, such as if the request is made in an inappropriate context. */
3514
3515 struct value *
3516 value_of_this (const struct language_defn *lang)
3517 {
3518 struct symbol *sym;
3519 struct block *b;
3520 struct frame_info *frame;
3521
3522 if (!lang->la_name_of_this)
3523 error (_("no `this' in current language"));
3524
3525 frame = get_selected_frame (_("no frame selected"));
3526
3527 b = get_frame_block (frame, NULL);
3528
3529 sym = lookup_language_this (lang, b);
3530 if (sym == NULL)
3531 error (_("current stack frame does not contain a variable named `%s'"),
3532 lang->la_name_of_this);
3533
3534 return read_var_value (sym, frame);
3535 }
3536
3537 /* Return the value of the local variable, if one exists. Return NULL
3538 otherwise. Never throw error. */
3539
3540 struct value *
3541 value_of_this_silent (const struct language_defn *lang)
3542 {
3543 struct value *ret = NULL;
3544 volatile struct gdb_exception except;
3545
3546 TRY_CATCH (except, RETURN_MASK_ERROR)
3547 {
3548 ret = value_of_this (lang);
3549 }
3550
3551 return ret;
3552 }
3553
3554 /* Create a slice (sub-string, sub-array) of ARRAY, that is LENGTH
3555 elements long, starting at LOWBOUND. The result has the same lower
3556 bound as the original ARRAY. */
3557
3558 struct value *
3559 value_slice (struct value *array, int lowbound, int length)
3560 {
3561 struct type *slice_range_type, *slice_type, *range_type;
3562 LONGEST lowerbound, upperbound;
3563 struct value *slice;
3564 struct type *array_type;
3565
3566 array_type = check_typedef (value_type (array));
3567 if (TYPE_CODE (array_type) != TYPE_CODE_ARRAY
3568 && TYPE_CODE (array_type) != TYPE_CODE_STRING)
3569 error (_("cannot take slice of non-array"));
3570
3571 range_type = TYPE_INDEX_TYPE (array_type);
3572 if (get_discrete_bounds (range_type, &lowerbound, &upperbound) < 0)
3573 error (_("slice from bad array or bitstring"));
3574
3575 if (lowbound < lowerbound || length < 0
3576 || lowbound + length - 1 > upperbound)
3577 error (_("slice out of range"));
3578
3579 /* FIXME-type-allocation: need a way to free this type when we are
3580 done with it. */
3581 slice_range_type = create_static_range_type ((struct type *) NULL,
3582 TYPE_TARGET_TYPE (range_type),
3583 lowbound,
3584 lowbound + length - 1);
3585
3586 {
3587 struct type *element_type = TYPE_TARGET_TYPE (array_type);
3588 LONGEST offset
3589 = (lowbound - lowerbound) * TYPE_LENGTH (check_typedef (element_type));
3590
3591 slice_type = create_array_type ((struct type *) NULL,
3592 element_type,
3593 slice_range_type);
3594 TYPE_CODE (slice_type) = TYPE_CODE (array_type);
3595
3596 if (VALUE_LVAL (array) == lval_memory && value_lazy (array))
3597 slice = allocate_value_lazy (slice_type);
3598 else
3599 {
3600 slice = allocate_value (slice_type);
3601 value_contents_copy (slice, 0, array, offset,
3602 TYPE_LENGTH (slice_type));
3603 }
3604
3605 set_value_component_location (slice, array);
3606 VALUE_FRAME_ID (slice) = VALUE_FRAME_ID (array);
3607 set_value_offset (slice, value_offset (array) + offset);
3608 }
3609
3610 return slice;
3611 }
3612
3613 /* Create a value for a FORTRAN complex number. Currently most of the
3614 time values are coerced to COMPLEX*16 (i.e. a complex number
3615 composed of 2 doubles. This really should be a smarter routine
3616 that figures out precision inteligently as opposed to assuming
3617 doubles. FIXME: fmb */
3618
3619 struct value *
3620 value_literal_complex (struct value *arg1,
3621 struct value *arg2,
3622 struct type *type)
3623 {
3624 struct value *val;
3625 struct type *real_type = TYPE_TARGET_TYPE (type);
3626
3627 val = allocate_value (type);
3628 arg1 = value_cast (real_type, arg1);
3629 arg2 = value_cast (real_type, arg2);
3630
3631 memcpy (value_contents_raw (val),
3632 value_contents (arg1), TYPE_LENGTH (real_type));
3633 memcpy (value_contents_raw (val) + TYPE_LENGTH (real_type),
3634 value_contents (arg2), TYPE_LENGTH (real_type));
3635 return val;
3636 }
3637
3638 /* Cast a value into the appropriate complex data type. */
3639
3640 static struct value *
3641 cast_into_complex (struct type *type, struct value *val)
3642 {
3643 struct type *real_type = TYPE_TARGET_TYPE (type);
3644
3645 if (TYPE_CODE (value_type (val)) == TYPE_CODE_COMPLEX)
3646 {
3647 struct type *val_real_type = TYPE_TARGET_TYPE (value_type (val));
3648 struct value *re_val = allocate_value (val_real_type);
3649 struct value *im_val = allocate_value (val_real_type);
3650
3651 memcpy (value_contents_raw (re_val),
3652 value_contents (val), TYPE_LENGTH (val_real_type));
3653 memcpy (value_contents_raw (im_val),
3654 value_contents (val) + TYPE_LENGTH (val_real_type),
3655 TYPE_LENGTH (val_real_type));
3656
3657 return value_literal_complex (re_val, im_val, type);
3658 }
3659 else if (TYPE_CODE (value_type (val)) == TYPE_CODE_FLT
3660 || TYPE_CODE (value_type (val)) == TYPE_CODE_INT)
3661 return value_literal_complex (val,
3662 value_zero (real_type, not_lval),
3663 type);
3664 else
3665 error (_("cannot cast non-number to complex"));
3666 }
3667
3668 void
3669 _initialize_valops (void)
3670 {
3671 add_setshow_boolean_cmd ("overload-resolution", class_support,
3672 &overload_resolution, _("\
3673 Set overload resolution in evaluating C++ functions."), _("\
3674 Show overload resolution in evaluating C++ functions."),
3675 NULL, NULL,
3676 show_overload_resolution,
3677 &setlist, &showlist);
3678 overload_resolution = 1;
3679 }
This page took 0.149563 seconds and 5 git commands to generate.