2011-01-11 Michael Snyder <msnyder@vmware.com>
[binutils-gdb.git] / gdb / valops.c
1 /* Perform non-arithmetic operations on values, for GDB.
2
3 Copyright (C) 1986, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995,
4 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007,
5 2008, 2009, 2010, 2011 Free Software Foundation, Inc.
6
7 This file is part of GDB.
8
9 This program is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 3 of the License, or
12 (at your option) any later version.
13
14 This program is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
18
19 You should have received a copy of the GNU General Public License
20 along with this program. If not, see <http://www.gnu.org/licenses/>. */
21
22 #include "defs.h"
23 #include "symtab.h"
24 #include "gdbtypes.h"
25 #include "value.h"
26 #include "frame.h"
27 #include "inferior.h"
28 #include "gdbcore.h"
29 #include "target.h"
30 #include "demangle.h"
31 #include "language.h"
32 #include "gdbcmd.h"
33 #include "regcache.h"
34 #include "cp-abi.h"
35 #include "block.h"
36 #include "infcall.h"
37 #include "dictionary.h"
38 #include "cp-support.h"
39 #include "dfp.h"
40 #include "user-regs.h"
41
42 #include <errno.h>
43 #include "gdb_string.h"
44 #include "gdb_assert.h"
45 #include "cp-support.h"
46 #include "observer.h"
47 #include "objfiles.h"
48 #include "symtab.h"
49 #include "exceptions.h"
50
51 extern int overload_debug;
52 /* Local functions. */
53
54 static int typecmp (int staticp, int varargs, int nargs,
55 struct field t1[], struct value *t2[]);
56
57 static struct value *search_struct_field (const char *, struct value *,
58 int, struct type *, int);
59
60 static struct value *search_struct_method (const char *, struct value **,
61 struct value **,
62 int, int *, struct type *);
63
64 static int find_oload_champ_namespace (struct type **, int,
65 const char *, const char *,
66 struct symbol ***,
67 struct badness_vector **,
68 const int no_adl);
69
70 static
71 int find_oload_champ_namespace_loop (struct type **, int,
72 const char *, const char *,
73 int, struct symbol ***,
74 struct badness_vector **, int *,
75 const int no_adl);
76
77 static int find_oload_champ (struct type **, int, int, int,
78 struct fn_field *, struct symbol **,
79 struct badness_vector **);
80
81 static int oload_method_static (int, struct fn_field *, int);
82
83 enum oload_classification { STANDARD, NON_STANDARD, INCOMPATIBLE };
84
85 static enum
86 oload_classification classify_oload_match (struct badness_vector *,
87 int, int);
88
89 static struct value *value_struct_elt_for_reference (struct type *,
90 int, struct type *,
91 char *,
92 struct type *,
93 int, enum noside);
94
95 static struct value *value_namespace_elt (const struct type *,
96 char *, int , enum noside);
97
98 static struct value *value_maybe_namespace_elt (const struct type *,
99 char *, int,
100 enum noside);
101
102 static CORE_ADDR allocate_space_in_inferior (int);
103
104 static struct value *cast_into_complex (struct type *, struct value *);
105
106 static struct fn_field *find_method_list (struct value **, const char *,
107 int, struct type *, int *,
108 struct type **, int *);
109
110 void _initialize_valops (void);
111
112 #if 0
113 /* Flag for whether we want to abandon failed expression evals by
114 default. */
115
116 static int auto_abandon = 0;
117 #endif
118
119 int overload_resolution = 0;
120 static void
121 show_overload_resolution (struct ui_file *file, int from_tty,
122 struct cmd_list_element *c,
123 const char *value)
124 {
125 fprintf_filtered (file, _("Overload resolution in evaluating "
126 "C++ functions is %s.\n"),
127 value);
128 }
129
130 /* Find the address of function name NAME in the inferior. If OBJF_P
131 is non-NULL, *OBJF_P will be set to the OBJFILE where the function
132 is defined. */
133
134 struct value *
135 find_function_in_inferior (const char *name, struct objfile **objf_p)
136 {
137 struct symbol *sym;
138
139 sym = lookup_symbol (name, 0, VAR_DOMAIN, 0);
140 if (sym != NULL)
141 {
142 if (SYMBOL_CLASS (sym) != LOC_BLOCK)
143 {
144 error (_("\"%s\" exists in this program but is not a function."),
145 name);
146 }
147
148 if (objf_p)
149 *objf_p = SYMBOL_SYMTAB (sym)->objfile;
150
151 return value_of_variable (sym, NULL);
152 }
153 else
154 {
155 struct minimal_symbol *msymbol =
156 lookup_minimal_symbol (name, NULL, NULL);
157
158 if (msymbol != NULL)
159 {
160 struct objfile *objfile = msymbol_objfile (msymbol);
161 struct gdbarch *gdbarch = get_objfile_arch (objfile);
162
163 struct type *type;
164 CORE_ADDR maddr;
165 type = lookup_pointer_type (builtin_type (gdbarch)->builtin_char);
166 type = lookup_function_type (type);
167 type = lookup_pointer_type (type);
168 maddr = SYMBOL_VALUE_ADDRESS (msymbol);
169
170 if (objf_p)
171 *objf_p = objfile;
172
173 return value_from_pointer (type, maddr);
174 }
175 else
176 {
177 if (!target_has_execution)
178 error (_("evaluation of this expression "
179 "requires the target program to be active"));
180 else
181 error (_("evaluation of this expression requires the "
182 "program to have a function \"%s\"."),
183 name);
184 }
185 }
186 }
187
188 /* Allocate NBYTES of space in the inferior using the inferior's
189 malloc and return a value that is a pointer to the allocated
190 space. */
191
192 struct value *
193 value_allocate_space_in_inferior (int len)
194 {
195 struct objfile *objf;
196 struct value *val = find_function_in_inferior ("malloc", &objf);
197 struct gdbarch *gdbarch = get_objfile_arch (objf);
198 struct value *blocklen;
199
200 blocklen = value_from_longest (builtin_type (gdbarch)->builtin_int, len);
201 val = call_function_by_hand (val, 1, &blocklen);
202 if (value_logical_not (val))
203 {
204 if (!target_has_execution)
205 error (_("No memory available to program now: "
206 "you need to start the target first"));
207 else
208 error (_("No memory available to program: call to malloc failed"));
209 }
210 return val;
211 }
212
213 static CORE_ADDR
214 allocate_space_in_inferior (int len)
215 {
216 return value_as_long (value_allocate_space_in_inferior (len));
217 }
218
219 /* Cast struct value VAL to type TYPE and return as a value.
220 Both type and val must be of TYPE_CODE_STRUCT or TYPE_CODE_UNION
221 for this to work. Typedef to one of the codes is permitted.
222 Returns NULL if the cast is neither an upcast nor a downcast. */
223
224 static struct value *
225 value_cast_structs (struct type *type, struct value *v2)
226 {
227 struct type *t1;
228 struct type *t2;
229 struct value *v;
230
231 gdb_assert (type != NULL && v2 != NULL);
232
233 t1 = check_typedef (type);
234 t2 = check_typedef (value_type (v2));
235
236 /* Check preconditions. */
237 gdb_assert ((TYPE_CODE (t1) == TYPE_CODE_STRUCT
238 || TYPE_CODE (t1) == TYPE_CODE_UNION)
239 && !!"Precondition is that type is of STRUCT or UNION kind.");
240 gdb_assert ((TYPE_CODE (t2) == TYPE_CODE_STRUCT
241 || TYPE_CODE (t2) == TYPE_CODE_UNION)
242 && !!"Precondition is that value is of STRUCT or UNION kind");
243
244 if (TYPE_NAME (t1) != NULL
245 && TYPE_NAME (t2) != NULL
246 && !strcmp (TYPE_NAME (t1), TYPE_NAME (t2)))
247 return NULL;
248
249 /* Upcasting: look in the type of the source to see if it contains the
250 type of the target as a superclass. If so, we'll need to
251 offset the pointer rather than just change its type. */
252 if (TYPE_NAME (t1) != NULL)
253 {
254 v = search_struct_field (type_name_no_tag (t1),
255 v2, 0, t2, 1);
256 if (v)
257 return v;
258 }
259
260 /* Downcasting: look in the type of the target to see if it contains the
261 type of the source as a superclass. If so, we'll need to
262 offset the pointer rather than just change its type. */
263 if (TYPE_NAME (t2) != NULL)
264 {
265 /* Try downcasting using the run-time type of the value. */
266 int full, top, using_enc;
267 struct type *real_type;
268
269 real_type = value_rtti_type (v2, &full, &top, &using_enc);
270 if (real_type)
271 {
272 v = value_full_object (v2, real_type, full, top, using_enc);
273 v = value_at_lazy (real_type, value_address (v));
274
275 /* We might be trying to cast to the outermost enclosing
276 type, in which case search_struct_field won't work. */
277 if (TYPE_NAME (real_type) != NULL
278 && !strcmp (TYPE_NAME (real_type), TYPE_NAME (t1)))
279 return v;
280
281 v = search_struct_field (type_name_no_tag (t2), v, 0, real_type, 1);
282 if (v)
283 return v;
284 }
285
286 /* Try downcasting using information from the destination type
287 T2. This wouldn't work properly for classes with virtual
288 bases, but those were handled above. */
289 v = search_struct_field (type_name_no_tag (t2),
290 value_zero (t1, not_lval), 0, t1, 1);
291 if (v)
292 {
293 /* Downcasting is possible (t1 is superclass of v2). */
294 CORE_ADDR addr2 = value_address (v2);
295
296 addr2 -= value_address (v) + value_embedded_offset (v);
297 return value_at (type, addr2);
298 }
299 }
300
301 return NULL;
302 }
303
304 /* Cast one pointer or reference type to another. Both TYPE and
305 the type of ARG2 should be pointer types, or else both should be
306 reference types. Returns the new pointer or reference. */
307
308 struct value *
309 value_cast_pointers (struct type *type, struct value *arg2)
310 {
311 struct type *type1 = check_typedef (type);
312 struct type *type2 = check_typedef (value_type (arg2));
313 struct type *t1 = check_typedef (TYPE_TARGET_TYPE (type1));
314 struct type *t2 = check_typedef (TYPE_TARGET_TYPE (type2));
315
316 if (TYPE_CODE (t1) == TYPE_CODE_STRUCT
317 && TYPE_CODE (t2) == TYPE_CODE_STRUCT
318 && !value_logical_not (arg2))
319 {
320 struct value *v2;
321
322 if (TYPE_CODE (type2) == TYPE_CODE_REF)
323 v2 = coerce_ref (arg2);
324 else
325 v2 = value_ind (arg2);
326 gdb_assert (TYPE_CODE (check_typedef (value_type (v2)))
327 == TYPE_CODE_STRUCT && !!"Why did coercion fail?");
328 v2 = value_cast_structs (t1, v2);
329 /* At this point we have what we can have, un-dereference if needed. */
330 if (v2)
331 {
332 struct value *v = value_addr (v2);
333
334 deprecated_set_value_type (v, type);
335 return v;
336 }
337 }
338
339 /* No superclass found, just change the pointer type. */
340 arg2 = value_copy (arg2);
341 deprecated_set_value_type (arg2, type);
342 set_value_enclosing_type (arg2, type);
343 set_value_pointed_to_offset (arg2, 0); /* pai: chk_val */
344 return arg2;
345 }
346
347 /* Cast value ARG2 to type TYPE and return as a value.
348 More general than a C cast: accepts any two types of the same length,
349 and if ARG2 is an lvalue it can be cast into anything at all. */
350 /* In C++, casts may change pointer or object representations. */
351
352 struct value *
353 value_cast (struct type *type, struct value *arg2)
354 {
355 enum type_code code1;
356 enum type_code code2;
357 int scalar;
358 struct type *type2;
359
360 int convert_to_boolean = 0;
361
362 if (value_type (arg2) == type)
363 return arg2;
364
365 code1 = TYPE_CODE (check_typedef (type));
366
367 /* Check if we are casting struct reference to struct reference. */
368 if (code1 == TYPE_CODE_REF)
369 {
370 /* We dereference type; then we recurse and finally
371 we generate value of the given reference. Nothing wrong with
372 that. */
373 struct type *t1 = check_typedef (type);
374 struct type *dereftype = check_typedef (TYPE_TARGET_TYPE (t1));
375 struct value *val = value_cast (dereftype, arg2);
376
377 return value_ref (val);
378 }
379
380 code2 = TYPE_CODE (check_typedef (value_type (arg2)));
381
382 if (code2 == TYPE_CODE_REF)
383 /* We deref the value and then do the cast. */
384 return value_cast (type, coerce_ref (arg2));
385
386 CHECK_TYPEDEF (type);
387 code1 = TYPE_CODE (type);
388 arg2 = coerce_ref (arg2);
389 type2 = check_typedef (value_type (arg2));
390
391 /* You can't cast to a reference type. See value_cast_pointers
392 instead. */
393 gdb_assert (code1 != TYPE_CODE_REF);
394
395 /* A cast to an undetermined-length array_type, such as
396 (TYPE [])OBJECT, is treated like a cast to (TYPE [N])OBJECT,
397 where N is sizeof(OBJECT)/sizeof(TYPE). */
398 if (code1 == TYPE_CODE_ARRAY)
399 {
400 struct type *element_type = TYPE_TARGET_TYPE (type);
401 unsigned element_length = TYPE_LENGTH (check_typedef (element_type));
402
403 if (element_length > 0 && TYPE_ARRAY_UPPER_BOUND_IS_UNDEFINED (type))
404 {
405 struct type *range_type = TYPE_INDEX_TYPE (type);
406 int val_length = TYPE_LENGTH (type2);
407 LONGEST low_bound, high_bound, new_length;
408
409 if (get_discrete_bounds (range_type, &low_bound, &high_bound) < 0)
410 low_bound = 0, high_bound = 0;
411 new_length = val_length / element_length;
412 if (val_length % element_length != 0)
413 warning (_("array element type size does not "
414 "divide object size in cast"));
415 /* FIXME-type-allocation: need a way to free this type when
416 we are done with it. */
417 range_type = create_range_type ((struct type *) NULL,
418 TYPE_TARGET_TYPE (range_type),
419 low_bound,
420 new_length + low_bound - 1);
421 deprecated_set_value_type (arg2,
422 create_array_type ((struct type *) NULL,
423 element_type,
424 range_type));
425 return arg2;
426 }
427 }
428
429 if (current_language->c_style_arrays
430 && TYPE_CODE (type2) == TYPE_CODE_ARRAY
431 && !TYPE_VECTOR (type2))
432 arg2 = value_coerce_array (arg2);
433
434 if (TYPE_CODE (type2) == TYPE_CODE_FUNC)
435 arg2 = value_coerce_function (arg2);
436
437 type2 = check_typedef (value_type (arg2));
438 code2 = TYPE_CODE (type2);
439
440 if (code1 == TYPE_CODE_COMPLEX)
441 return cast_into_complex (type, arg2);
442 if (code1 == TYPE_CODE_BOOL)
443 {
444 code1 = TYPE_CODE_INT;
445 convert_to_boolean = 1;
446 }
447 if (code1 == TYPE_CODE_CHAR)
448 code1 = TYPE_CODE_INT;
449 if (code2 == TYPE_CODE_BOOL || code2 == TYPE_CODE_CHAR)
450 code2 = TYPE_CODE_INT;
451
452 scalar = (code2 == TYPE_CODE_INT || code2 == TYPE_CODE_FLT
453 || code2 == TYPE_CODE_DECFLOAT || code2 == TYPE_CODE_ENUM
454 || code2 == TYPE_CODE_RANGE);
455
456 if ((code1 == TYPE_CODE_STRUCT || code1 == TYPE_CODE_UNION)
457 && (code2 == TYPE_CODE_STRUCT || code2 == TYPE_CODE_UNION)
458 && TYPE_NAME (type) != 0)
459 {
460 struct value *v = value_cast_structs (type, arg2);
461
462 if (v)
463 return v;
464 }
465
466 if (code1 == TYPE_CODE_FLT && scalar)
467 return value_from_double (type, value_as_double (arg2));
468 else if (code1 == TYPE_CODE_DECFLOAT && scalar)
469 {
470 enum bfd_endian byte_order = gdbarch_byte_order (get_type_arch (type));
471 int dec_len = TYPE_LENGTH (type);
472 gdb_byte dec[16];
473
474 if (code2 == TYPE_CODE_FLT)
475 decimal_from_floating (arg2, dec, dec_len, byte_order);
476 else if (code2 == TYPE_CODE_DECFLOAT)
477 decimal_convert (value_contents (arg2), TYPE_LENGTH (type2),
478 byte_order, dec, dec_len, byte_order);
479 else
480 /* The only option left is an integral type. */
481 decimal_from_integral (arg2, dec, dec_len, byte_order);
482
483 return value_from_decfloat (type, dec);
484 }
485 else if ((code1 == TYPE_CODE_INT || code1 == TYPE_CODE_ENUM
486 || code1 == TYPE_CODE_RANGE)
487 && (scalar || code2 == TYPE_CODE_PTR
488 || code2 == TYPE_CODE_MEMBERPTR))
489 {
490 LONGEST longest;
491
492 /* When we cast pointers to integers, we mustn't use
493 gdbarch_pointer_to_address to find the address the pointer
494 represents, as value_as_long would. GDB should evaluate
495 expressions just as the compiler would --- and the compiler
496 sees a cast as a simple reinterpretation of the pointer's
497 bits. */
498 if (code2 == TYPE_CODE_PTR)
499 longest = extract_unsigned_integer
500 (value_contents (arg2), TYPE_LENGTH (type2),
501 gdbarch_byte_order (get_type_arch (type2)));
502 else
503 longest = value_as_long (arg2);
504 return value_from_longest (type, convert_to_boolean ?
505 (LONGEST) (longest ? 1 : 0) : longest);
506 }
507 else if (code1 == TYPE_CODE_PTR && (code2 == TYPE_CODE_INT
508 || code2 == TYPE_CODE_ENUM
509 || code2 == TYPE_CODE_RANGE))
510 {
511 /* TYPE_LENGTH (type) is the length of a pointer, but we really
512 want the length of an address! -- we are really dealing with
513 addresses (i.e., gdb representations) not pointers (i.e.,
514 target representations) here.
515
516 This allows things like "print *(int *)0x01000234" to work
517 without printing a misleading message -- which would
518 otherwise occur when dealing with a target having two byte
519 pointers and four byte addresses. */
520
521 int addr_bit = gdbarch_addr_bit (get_type_arch (type2));
522 LONGEST longest = value_as_long (arg2);
523
524 if (addr_bit < sizeof (LONGEST) * HOST_CHAR_BIT)
525 {
526 if (longest >= ((LONGEST) 1 << addr_bit)
527 || longest <= -((LONGEST) 1 << addr_bit))
528 warning (_("value truncated"));
529 }
530 return value_from_longest (type, longest);
531 }
532 else if (code1 == TYPE_CODE_METHODPTR && code2 == TYPE_CODE_INT
533 && value_as_long (arg2) == 0)
534 {
535 struct value *result = allocate_value (type);
536
537 cplus_make_method_ptr (type, value_contents_writeable (result), 0, 0);
538 return result;
539 }
540 else if (code1 == TYPE_CODE_MEMBERPTR && code2 == TYPE_CODE_INT
541 && value_as_long (arg2) == 0)
542 {
543 /* The Itanium C++ ABI represents NULL pointers to members as
544 minus one, instead of biasing the normal case. */
545 return value_from_longest (type, -1);
546 }
547 else if (code1 == TYPE_CODE_ARRAY && TYPE_VECTOR (type) && scalar)
548 {
549 /* Widen the scalar to a vector. */
550 struct type *eltype;
551 struct value *val;
552 LONGEST low_bound, high_bound;
553 int i;
554
555 if (!get_array_bounds (type, &low_bound, &high_bound))
556 error (_("Could not determine the vector bounds"));
557
558 eltype = check_typedef (TYPE_TARGET_TYPE (type));
559 arg2 = value_cast (eltype, arg2);
560 val = allocate_value (type);
561
562 for (i = 0; i < high_bound - low_bound + 1; i++)
563 {
564 /* Duplicate the contents of arg2 into the destination vector. */
565 memcpy (value_contents_writeable (val) + (i * TYPE_LENGTH (eltype)),
566 value_contents_all (arg2), TYPE_LENGTH (eltype));
567 }
568 return val;
569 }
570 else if (TYPE_LENGTH (type) == TYPE_LENGTH (type2))
571 {
572 if (code1 == TYPE_CODE_PTR && code2 == TYPE_CODE_PTR)
573 return value_cast_pointers (type, arg2);
574
575 arg2 = value_copy (arg2);
576 deprecated_set_value_type (arg2, type);
577 set_value_enclosing_type (arg2, type);
578 set_value_pointed_to_offset (arg2, 0); /* pai: chk_val */
579 return arg2;
580 }
581 else if (VALUE_LVAL (arg2) == lval_memory)
582 return value_at_lazy (type, value_address (arg2));
583 else if (code1 == TYPE_CODE_VOID)
584 {
585 return value_zero (type, not_lval);
586 }
587 else
588 {
589 error (_("Invalid cast."));
590 return 0;
591 }
592 }
593
594 /* The C++ reinterpret_cast operator. */
595
596 struct value *
597 value_reinterpret_cast (struct type *type, struct value *arg)
598 {
599 struct value *result;
600 struct type *real_type = check_typedef (type);
601 struct type *arg_type, *dest_type;
602 int is_ref = 0;
603 enum type_code dest_code, arg_code;
604
605 /* Do reference, function, and array conversion. */
606 arg = coerce_array (arg);
607
608 /* Attempt to preserve the type the user asked for. */
609 dest_type = type;
610
611 /* If we are casting to a reference type, transform
612 reinterpret_cast<T&>(V) to *reinterpret_cast<T*>(&V). */
613 if (TYPE_CODE (real_type) == TYPE_CODE_REF)
614 {
615 is_ref = 1;
616 arg = value_addr (arg);
617 dest_type = lookup_pointer_type (TYPE_TARGET_TYPE (dest_type));
618 real_type = lookup_pointer_type (real_type);
619 }
620
621 arg_type = value_type (arg);
622
623 dest_code = TYPE_CODE (real_type);
624 arg_code = TYPE_CODE (arg_type);
625
626 /* We can convert pointer types, or any pointer type to int, or int
627 type to pointer. */
628 if ((dest_code == TYPE_CODE_PTR && arg_code == TYPE_CODE_INT)
629 || (dest_code == TYPE_CODE_INT && arg_code == TYPE_CODE_PTR)
630 || (dest_code == TYPE_CODE_METHODPTR && arg_code == TYPE_CODE_INT)
631 || (dest_code == TYPE_CODE_INT && arg_code == TYPE_CODE_METHODPTR)
632 || (dest_code == TYPE_CODE_MEMBERPTR && arg_code == TYPE_CODE_INT)
633 || (dest_code == TYPE_CODE_INT && arg_code == TYPE_CODE_MEMBERPTR)
634 || (dest_code == arg_code
635 && (dest_code == TYPE_CODE_PTR
636 || dest_code == TYPE_CODE_METHODPTR
637 || dest_code == TYPE_CODE_MEMBERPTR)))
638 result = value_cast (dest_type, arg);
639 else
640 error (_("Invalid reinterpret_cast"));
641
642 if (is_ref)
643 result = value_cast (type, value_ref (value_ind (result)));
644
645 return result;
646 }
647
648 /* A helper for value_dynamic_cast. This implements the first of two
649 runtime checks: we iterate over all the base classes of the value's
650 class which are equal to the desired class; if only one of these
651 holds the value, then it is the answer. */
652
653 static int
654 dynamic_cast_check_1 (struct type *desired_type,
655 const bfd_byte *contents,
656 CORE_ADDR address,
657 struct type *search_type,
658 CORE_ADDR arg_addr,
659 struct type *arg_type,
660 struct value **result)
661 {
662 int i, result_count = 0;
663
664 for (i = 0; i < TYPE_N_BASECLASSES (search_type) && result_count < 2; ++i)
665 {
666 int offset = baseclass_offset (search_type, i, contents, address);
667
668 if (offset == -1)
669 error (_("virtual baseclass botch"));
670 if (class_types_same_p (desired_type, TYPE_BASECLASS (search_type, i)))
671 {
672 if (address + offset >= arg_addr
673 && address + offset < arg_addr + TYPE_LENGTH (arg_type))
674 {
675 ++result_count;
676 if (!*result)
677 *result = value_at_lazy (TYPE_BASECLASS (search_type, i),
678 address + offset);
679 }
680 }
681 else
682 result_count += dynamic_cast_check_1 (desired_type,
683 contents + offset,
684 address + offset,
685 TYPE_BASECLASS (search_type, i),
686 arg_addr,
687 arg_type,
688 result);
689 }
690
691 return result_count;
692 }
693
694 /* A helper for value_dynamic_cast. This implements the second of two
695 runtime checks: we look for a unique public sibling class of the
696 argument's declared class. */
697
698 static int
699 dynamic_cast_check_2 (struct type *desired_type,
700 const bfd_byte *contents,
701 CORE_ADDR address,
702 struct type *search_type,
703 struct value **result)
704 {
705 int i, result_count = 0;
706
707 for (i = 0; i < TYPE_N_BASECLASSES (search_type) && result_count < 2; ++i)
708 {
709 int offset;
710
711 if (! BASETYPE_VIA_PUBLIC (search_type, i))
712 continue;
713
714 offset = baseclass_offset (search_type, i, contents, address);
715 if (offset == -1)
716 error (_("virtual baseclass botch"));
717 if (class_types_same_p (desired_type, TYPE_BASECLASS (search_type, i)))
718 {
719 ++result_count;
720 if (*result == NULL)
721 *result = value_at_lazy (TYPE_BASECLASS (search_type, i),
722 address + offset);
723 }
724 else
725 result_count += dynamic_cast_check_2 (desired_type,
726 contents + offset,
727 address + offset,
728 TYPE_BASECLASS (search_type, i),
729 result);
730 }
731
732 return result_count;
733 }
734
735 /* The C++ dynamic_cast operator. */
736
737 struct value *
738 value_dynamic_cast (struct type *type, struct value *arg)
739 {
740 int full, top, using_enc;
741 struct type *resolved_type = check_typedef (type);
742 struct type *arg_type = check_typedef (value_type (arg));
743 struct type *class_type, *rtti_type;
744 struct value *result, *tem, *original_arg = arg;
745 CORE_ADDR addr;
746 int is_ref = TYPE_CODE (resolved_type) == TYPE_CODE_REF;
747
748 if (TYPE_CODE (resolved_type) != TYPE_CODE_PTR
749 && TYPE_CODE (resolved_type) != TYPE_CODE_REF)
750 error (_("Argument to dynamic_cast must be a pointer or reference type"));
751 if (TYPE_CODE (TYPE_TARGET_TYPE (resolved_type)) != TYPE_CODE_VOID
752 && TYPE_CODE (TYPE_TARGET_TYPE (resolved_type)) != TYPE_CODE_CLASS)
753 error (_("Argument to dynamic_cast must be pointer to class or `void *'"));
754
755 class_type = check_typedef (TYPE_TARGET_TYPE (resolved_type));
756 if (TYPE_CODE (resolved_type) == TYPE_CODE_PTR)
757 {
758 if (TYPE_CODE (arg_type) != TYPE_CODE_PTR
759 && ! (TYPE_CODE (arg_type) == TYPE_CODE_INT
760 && value_as_long (arg) == 0))
761 error (_("Argument to dynamic_cast does not have pointer type"));
762 if (TYPE_CODE (arg_type) == TYPE_CODE_PTR)
763 {
764 arg_type = check_typedef (TYPE_TARGET_TYPE (arg_type));
765 if (TYPE_CODE (arg_type) != TYPE_CODE_CLASS)
766 error (_("Argument to dynamic_cast does "
767 "not have pointer to class type"));
768 }
769
770 /* Handle NULL pointers. */
771 if (value_as_long (arg) == 0)
772 return value_zero (type, not_lval);
773
774 arg = value_ind (arg);
775 }
776 else
777 {
778 if (TYPE_CODE (arg_type) != TYPE_CODE_CLASS)
779 error (_("Argument to dynamic_cast does not have class type"));
780 }
781
782 /* If the classes are the same, just return the argument. */
783 if (class_types_same_p (class_type, arg_type))
784 return value_cast (type, arg);
785
786 /* If the target type is a unique base class of the argument's
787 declared type, just cast it. */
788 if (is_ancestor (class_type, arg_type))
789 {
790 if (is_unique_ancestor (class_type, arg))
791 return value_cast (type, original_arg);
792 error (_("Ambiguous dynamic_cast"));
793 }
794
795 rtti_type = value_rtti_type (arg, &full, &top, &using_enc);
796 if (! rtti_type)
797 error (_("Couldn't determine value's most derived type for dynamic_cast"));
798
799 /* Compute the most derived object's address. */
800 addr = value_address (arg);
801 if (full)
802 {
803 /* Done. */
804 }
805 else if (using_enc)
806 addr += top;
807 else
808 addr += top + value_embedded_offset (arg);
809
810 /* dynamic_cast<void *> means to return a pointer to the
811 most-derived object. */
812 if (TYPE_CODE (resolved_type) == TYPE_CODE_PTR
813 && TYPE_CODE (TYPE_TARGET_TYPE (resolved_type)) == TYPE_CODE_VOID)
814 return value_at_lazy (type, addr);
815
816 tem = value_at (type, addr);
817
818 /* The first dynamic check specified in 5.2.7. */
819 if (is_public_ancestor (arg_type, TYPE_TARGET_TYPE (resolved_type)))
820 {
821 if (class_types_same_p (rtti_type, TYPE_TARGET_TYPE (resolved_type)))
822 return tem;
823 result = NULL;
824 if (dynamic_cast_check_1 (TYPE_TARGET_TYPE (resolved_type),
825 value_contents (tem), value_address (tem),
826 rtti_type, addr,
827 arg_type,
828 &result) == 1)
829 return value_cast (type,
830 is_ref ? value_ref (result) : value_addr (result));
831 }
832
833 /* The second dynamic check specified in 5.2.7. */
834 result = NULL;
835 if (is_public_ancestor (arg_type, rtti_type)
836 && dynamic_cast_check_2 (TYPE_TARGET_TYPE (resolved_type),
837 value_contents (tem), value_address (tem),
838 rtti_type, &result) == 1)
839 return value_cast (type,
840 is_ref ? value_ref (result) : value_addr (result));
841
842 if (TYPE_CODE (resolved_type) == TYPE_CODE_PTR)
843 return value_zero (type, not_lval);
844
845 error (_("dynamic_cast failed"));
846 }
847
848 /* Create a value of type TYPE that is zero, and return it. */
849
850 struct value *
851 value_zero (struct type *type, enum lval_type lv)
852 {
853 struct value *val = allocate_value (type);
854
855 VALUE_LVAL (val) = lv;
856 return val;
857 }
858
859 /* Create a value of numeric type TYPE that is one, and return it. */
860
861 struct value *
862 value_one (struct type *type, enum lval_type lv)
863 {
864 struct type *type1 = check_typedef (type);
865 struct value *val;
866
867 if (TYPE_CODE (type1) == TYPE_CODE_DECFLOAT)
868 {
869 enum bfd_endian byte_order = gdbarch_byte_order (get_type_arch (type));
870 gdb_byte v[16];
871
872 decimal_from_string (v, TYPE_LENGTH (type), byte_order, "1");
873 val = value_from_decfloat (type, v);
874 }
875 else if (TYPE_CODE (type1) == TYPE_CODE_FLT)
876 {
877 val = value_from_double (type, (DOUBLEST) 1);
878 }
879 else if (is_integral_type (type1))
880 {
881 val = value_from_longest (type, (LONGEST) 1);
882 }
883 else if (TYPE_CODE (type1) == TYPE_CODE_ARRAY && TYPE_VECTOR (type1))
884 {
885 struct type *eltype = check_typedef (TYPE_TARGET_TYPE (type1));
886 int i;
887 LONGEST low_bound, high_bound;
888 struct value *tmp;
889
890 if (!get_array_bounds (type1, &low_bound, &high_bound))
891 error (_("Could not determine the vector bounds"));
892
893 val = allocate_value (type);
894 for (i = 0; i < high_bound - low_bound + 1; i++)
895 {
896 tmp = value_one (eltype, lv);
897 memcpy (value_contents_writeable (val) + i * TYPE_LENGTH (eltype),
898 value_contents_all (tmp), TYPE_LENGTH (eltype));
899 }
900 }
901 else
902 {
903 error (_("Not a numeric type."));
904 }
905
906 VALUE_LVAL (val) = lv;
907 return val;
908 }
909
910 /* Helper function for value_at, value_at_lazy, and value_at_lazy_stack. */
911
912 static struct value *
913 get_value_at (struct type *type, CORE_ADDR addr, int lazy)
914 {
915 struct value *val;
916
917 if (TYPE_CODE (check_typedef (type)) == TYPE_CODE_VOID)
918 error (_("Attempt to dereference a generic pointer."));
919
920 if (lazy)
921 {
922 val = allocate_value_lazy (type);
923 }
924 else
925 {
926 val = allocate_value (type);
927 read_memory (addr, value_contents_all_raw (val), TYPE_LENGTH (type));
928 }
929
930 VALUE_LVAL (val) = lval_memory;
931 set_value_address (val, addr);
932
933 return val;
934 }
935
936 /* Return a value with type TYPE located at ADDR.
937
938 Call value_at only if the data needs to be fetched immediately;
939 if we can be 'lazy' and defer the fetch, perhaps indefinately, call
940 value_at_lazy instead. value_at_lazy simply records the address of
941 the data and sets the lazy-evaluation-required flag. The lazy flag
942 is tested in the value_contents macro, which is used if and when
943 the contents are actually required.
944
945 Note: value_at does *NOT* handle embedded offsets; perform such
946 adjustments before or after calling it. */
947
948 struct value *
949 value_at (struct type *type, CORE_ADDR addr)
950 {
951 return get_value_at (type, addr, 0);
952 }
953
954 /* Return a lazy value with type TYPE located at ADDR (cf. value_at). */
955
956 struct value *
957 value_at_lazy (struct type *type, CORE_ADDR addr)
958 {
959 return get_value_at (type, addr, 1);
960 }
961
962 /* Called only from the value_contents and value_contents_all()
963 macros, if the current data for a variable needs to be loaded into
964 value_contents(VAL). Fetches the data from the user's process, and
965 clears the lazy flag to indicate that the data in the buffer is
966 valid.
967
968 If the value is zero-length, we avoid calling read_memory, which
969 would abort. We mark the value as fetched anyway -- all 0 bytes of
970 it.
971
972 This function returns a value because it is used in the
973 value_contents macro as part of an expression, where a void would
974 not work. The value is ignored. */
975
976 int
977 value_fetch_lazy (struct value *val)
978 {
979 gdb_assert (value_lazy (val));
980 allocate_value_contents (val);
981 if (value_bitsize (val))
982 {
983 /* To read a lazy bitfield, read the entire enclosing value. This
984 prevents reading the same block of (possibly volatile) memory once
985 per bitfield. It would be even better to read only the containing
986 word, but we have no way to record that just specific bits of a
987 value have been fetched. */
988 struct type *type = check_typedef (value_type (val));
989 enum bfd_endian byte_order = gdbarch_byte_order (get_type_arch (type));
990 struct value *parent = value_parent (val);
991 LONGEST offset = value_offset (val);
992 LONGEST num = unpack_bits_as_long (value_type (val),
993 (value_contents_for_printing (parent)
994 + offset),
995 value_bitpos (val),
996 value_bitsize (val));
997 int length = TYPE_LENGTH (type);
998
999 if (!value_bits_valid (val,
1000 TARGET_CHAR_BIT * offset + value_bitpos (val),
1001 value_bitsize (val)))
1002 error (_("value has been optimized out"));
1003
1004 store_signed_integer (value_contents_raw (val), length, byte_order, num);
1005 }
1006 else if (VALUE_LVAL (val) == lval_memory)
1007 {
1008 CORE_ADDR addr = value_address (val);
1009 int length = TYPE_LENGTH (check_typedef (value_enclosing_type (val)));
1010
1011 if (length)
1012 {
1013 if (value_stack (val))
1014 read_stack (addr, value_contents_all_raw (val), length);
1015 else
1016 read_memory (addr, value_contents_all_raw (val), length);
1017 }
1018 }
1019 else if (VALUE_LVAL (val) == lval_register)
1020 {
1021 struct frame_info *frame;
1022 int regnum;
1023 struct type *type = check_typedef (value_type (val));
1024 struct value *new_val = val, *mark = value_mark ();
1025
1026 /* Offsets are not supported here; lazy register values must
1027 refer to the entire register. */
1028 gdb_assert (value_offset (val) == 0);
1029
1030 while (VALUE_LVAL (new_val) == lval_register && value_lazy (new_val))
1031 {
1032 frame = frame_find_by_id (VALUE_FRAME_ID (new_val));
1033 regnum = VALUE_REGNUM (new_val);
1034
1035 gdb_assert (frame != NULL);
1036
1037 /* Convertible register routines are used for multi-register
1038 values and for interpretation in different types
1039 (e.g. float or int from a double register). Lazy
1040 register values should have the register's natural type,
1041 so they do not apply. */
1042 gdb_assert (!gdbarch_convert_register_p (get_frame_arch (frame),
1043 regnum, type));
1044
1045 new_val = get_frame_register_value (frame, regnum);
1046 }
1047
1048 /* If it's still lazy (for instance, a saved register on the
1049 stack), fetch it. */
1050 if (value_lazy (new_val))
1051 value_fetch_lazy (new_val);
1052
1053 /* If the register was not saved, mark it unavailable. */
1054 if (value_optimized_out (new_val))
1055 set_value_optimized_out (val, 1);
1056 else
1057 memcpy (value_contents_raw (val), value_contents (new_val),
1058 TYPE_LENGTH (type));
1059
1060 if (frame_debug)
1061 {
1062 struct gdbarch *gdbarch;
1063 frame = frame_find_by_id (VALUE_FRAME_ID (val));
1064 regnum = VALUE_REGNUM (val);
1065 gdbarch = get_frame_arch (frame);
1066
1067 fprintf_unfiltered (gdb_stdlog,
1068 "{ value_fetch_lazy "
1069 "(frame=%d,regnum=%d(%s),...) ",
1070 frame_relative_level (frame), regnum,
1071 user_reg_map_regnum_to_name (gdbarch, regnum));
1072
1073 fprintf_unfiltered (gdb_stdlog, "->");
1074 if (value_optimized_out (new_val))
1075 fprintf_unfiltered (gdb_stdlog, " optimized out");
1076 else
1077 {
1078 int i;
1079 const gdb_byte *buf = value_contents (new_val);
1080
1081 if (VALUE_LVAL (new_val) == lval_register)
1082 fprintf_unfiltered (gdb_stdlog, " register=%d",
1083 VALUE_REGNUM (new_val));
1084 else if (VALUE_LVAL (new_val) == lval_memory)
1085 fprintf_unfiltered (gdb_stdlog, " address=%s",
1086 paddress (gdbarch,
1087 value_address (new_val)));
1088 else
1089 fprintf_unfiltered (gdb_stdlog, " computed");
1090
1091 fprintf_unfiltered (gdb_stdlog, " bytes=");
1092 fprintf_unfiltered (gdb_stdlog, "[");
1093 for (i = 0; i < register_size (gdbarch, regnum); i++)
1094 fprintf_unfiltered (gdb_stdlog, "%02x", buf[i]);
1095 fprintf_unfiltered (gdb_stdlog, "]");
1096 }
1097
1098 fprintf_unfiltered (gdb_stdlog, " }\n");
1099 }
1100
1101 /* Dispose of the intermediate values. This prevents
1102 watchpoints from trying to watch the saved frame pointer. */
1103 value_free_to_mark (mark);
1104 }
1105 else if (VALUE_LVAL (val) == lval_computed)
1106 value_computed_funcs (val)->read (val);
1107 else
1108 internal_error (__FILE__, __LINE__, _("Unexpected lazy value type."));
1109
1110 set_value_lazy (val, 0);
1111 return 0;
1112 }
1113
1114
1115 /* Store the contents of FROMVAL into the location of TOVAL.
1116 Return a new value with the location of TOVAL and contents of FROMVAL. */
1117
1118 struct value *
1119 value_assign (struct value *toval, struct value *fromval)
1120 {
1121 struct type *type;
1122 struct value *val;
1123 struct frame_id old_frame;
1124
1125 if (!deprecated_value_modifiable (toval))
1126 error (_("Left operand of assignment is not a modifiable lvalue."));
1127
1128 toval = coerce_ref (toval);
1129
1130 type = value_type (toval);
1131 if (VALUE_LVAL (toval) != lval_internalvar)
1132 fromval = value_cast (type, fromval);
1133 else
1134 {
1135 /* Coerce arrays and functions to pointers, except for arrays
1136 which only live in GDB's storage. */
1137 if (!value_must_coerce_to_target (fromval))
1138 fromval = coerce_array (fromval);
1139 }
1140
1141 CHECK_TYPEDEF (type);
1142
1143 /* Since modifying a register can trash the frame chain, and
1144 modifying memory can trash the frame cache, we save the old frame
1145 and then restore the new frame afterwards. */
1146 old_frame = get_frame_id (deprecated_safe_get_selected_frame ());
1147
1148 switch (VALUE_LVAL (toval))
1149 {
1150 case lval_internalvar:
1151 set_internalvar (VALUE_INTERNALVAR (toval), fromval);
1152 return value_of_internalvar (get_type_arch (type),
1153 VALUE_INTERNALVAR (toval));
1154
1155 case lval_internalvar_component:
1156 set_internalvar_component (VALUE_INTERNALVAR (toval),
1157 value_offset (toval),
1158 value_bitpos (toval),
1159 value_bitsize (toval),
1160 fromval);
1161 break;
1162
1163 case lval_memory:
1164 {
1165 const gdb_byte *dest_buffer;
1166 CORE_ADDR changed_addr;
1167 int changed_len;
1168 gdb_byte buffer[sizeof (LONGEST)];
1169
1170 if (value_bitsize (toval))
1171 {
1172 struct value *parent = value_parent (toval);
1173
1174 changed_addr = value_address (parent) + value_offset (toval);
1175 changed_len = (value_bitpos (toval)
1176 + value_bitsize (toval)
1177 + HOST_CHAR_BIT - 1)
1178 / HOST_CHAR_BIT;
1179
1180 /* If we can read-modify-write exactly the size of the
1181 containing type (e.g. short or int) then do so. This
1182 is safer for volatile bitfields mapped to hardware
1183 registers. */
1184 if (changed_len < TYPE_LENGTH (type)
1185 && TYPE_LENGTH (type) <= (int) sizeof (LONGEST)
1186 && ((LONGEST) changed_addr % TYPE_LENGTH (type)) == 0)
1187 changed_len = TYPE_LENGTH (type);
1188
1189 if (changed_len > (int) sizeof (LONGEST))
1190 error (_("Can't handle bitfields which "
1191 "don't fit in a %d bit word."),
1192 (int) sizeof (LONGEST) * HOST_CHAR_BIT);
1193
1194 read_memory (changed_addr, buffer, changed_len);
1195 modify_field (type, buffer, value_as_long (fromval),
1196 value_bitpos (toval), value_bitsize (toval));
1197 dest_buffer = buffer;
1198 }
1199 else
1200 {
1201 changed_addr = value_address (toval);
1202 changed_len = TYPE_LENGTH (type);
1203 dest_buffer = value_contents (fromval);
1204 }
1205
1206 write_memory (changed_addr, dest_buffer, changed_len);
1207 observer_notify_memory_changed (changed_addr, changed_len,
1208 dest_buffer);
1209 }
1210 break;
1211
1212 case lval_register:
1213 {
1214 struct frame_info *frame;
1215 struct gdbarch *gdbarch;
1216 int value_reg;
1217
1218 /* Figure out which frame this is in currently. */
1219 frame = frame_find_by_id (VALUE_FRAME_ID (toval));
1220 value_reg = VALUE_REGNUM (toval);
1221
1222 if (!frame)
1223 error (_("Value being assigned to is no longer active."));
1224
1225 gdbarch = get_frame_arch (frame);
1226 if (gdbarch_convert_register_p (gdbarch, VALUE_REGNUM (toval), type))
1227 {
1228 /* If TOVAL is a special machine register requiring
1229 conversion of program values to a special raw
1230 format. */
1231 gdbarch_value_to_register (gdbarch, frame,
1232 VALUE_REGNUM (toval), type,
1233 value_contents (fromval));
1234 }
1235 else
1236 {
1237 if (value_bitsize (toval))
1238 {
1239 struct value *parent = value_parent (toval);
1240 int offset = value_offset (parent) + value_offset (toval);
1241 int changed_len;
1242 gdb_byte buffer[sizeof (LONGEST)];
1243
1244 changed_len = (value_bitpos (toval)
1245 + value_bitsize (toval)
1246 + HOST_CHAR_BIT - 1)
1247 / HOST_CHAR_BIT;
1248
1249 if (changed_len > (int) sizeof (LONGEST))
1250 error (_("Can't handle bitfields which "
1251 "don't fit in a %d bit word."),
1252 (int) sizeof (LONGEST) * HOST_CHAR_BIT);
1253
1254 get_frame_register_bytes (frame, value_reg, offset,
1255 changed_len, buffer);
1256
1257 modify_field (type, buffer, value_as_long (fromval),
1258 value_bitpos (toval), value_bitsize (toval));
1259
1260 put_frame_register_bytes (frame, value_reg, offset,
1261 changed_len, buffer);
1262 }
1263 else
1264 {
1265 put_frame_register_bytes (frame, value_reg,
1266 value_offset (toval),
1267 TYPE_LENGTH (type),
1268 value_contents (fromval));
1269 }
1270 }
1271
1272 if (deprecated_register_changed_hook)
1273 deprecated_register_changed_hook (-1);
1274 observer_notify_target_changed (&current_target);
1275 break;
1276 }
1277
1278 case lval_computed:
1279 {
1280 struct lval_funcs *funcs = value_computed_funcs (toval);
1281
1282 funcs->write (toval, fromval);
1283 }
1284 break;
1285
1286 default:
1287 error (_("Left operand of assignment is not an lvalue."));
1288 }
1289
1290 /* Assigning to the stack pointer, frame pointer, and other
1291 (architecture and calling convention specific) registers may
1292 cause the frame cache to be out of date. Assigning to memory
1293 also can. We just do this on all assignments to registers or
1294 memory, for simplicity's sake; I doubt the slowdown matters. */
1295 switch (VALUE_LVAL (toval))
1296 {
1297 case lval_memory:
1298 case lval_register:
1299 case lval_computed:
1300
1301 reinit_frame_cache ();
1302
1303 /* Having destroyed the frame cache, restore the selected
1304 frame. */
1305
1306 /* FIXME: cagney/2002-11-02: There has to be a better way of
1307 doing this. Instead of constantly saving/restoring the
1308 frame. Why not create a get_selected_frame() function that,
1309 having saved the selected frame's ID can automatically
1310 re-find the previously selected frame automatically. */
1311
1312 {
1313 struct frame_info *fi = frame_find_by_id (old_frame);
1314
1315 if (fi != NULL)
1316 select_frame (fi);
1317 }
1318
1319 break;
1320 default:
1321 break;
1322 }
1323
1324 /* If the field does not entirely fill a LONGEST, then zero the sign
1325 bits. If the field is signed, and is negative, then sign
1326 extend. */
1327 if ((value_bitsize (toval) > 0)
1328 && (value_bitsize (toval) < 8 * (int) sizeof (LONGEST)))
1329 {
1330 LONGEST fieldval = value_as_long (fromval);
1331 LONGEST valmask = (((ULONGEST) 1) << value_bitsize (toval)) - 1;
1332
1333 fieldval &= valmask;
1334 if (!TYPE_UNSIGNED (type)
1335 && (fieldval & (valmask ^ (valmask >> 1))))
1336 fieldval |= ~valmask;
1337
1338 fromval = value_from_longest (type, fieldval);
1339 }
1340
1341 /* The return value is a copy of TOVAL so it shares its location
1342 information, but its contents are updated from FROMVAL. This
1343 implies the returned value is not lazy, even if TOVAL was. */
1344 val = value_copy (toval);
1345 set_value_lazy (val, 0);
1346 memcpy (value_contents_raw (val), value_contents (fromval),
1347 TYPE_LENGTH (type));
1348
1349 /* We copy over the enclosing type and pointed-to offset from FROMVAL
1350 in the case of pointer types. For object types, the enclosing type
1351 and embedded offset must *not* be copied: the target object refered
1352 to by TOVAL retains its original dynamic type after assignment. */
1353 if (TYPE_CODE (type) == TYPE_CODE_PTR)
1354 {
1355 set_value_enclosing_type (val, value_enclosing_type (fromval));
1356 set_value_pointed_to_offset (val, value_pointed_to_offset (fromval));
1357 }
1358
1359 return val;
1360 }
1361
1362 /* Extend a value VAL to COUNT repetitions of its type. */
1363
1364 struct value *
1365 value_repeat (struct value *arg1, int count)
1366 {
1367 struct value *val;
1368
1369 if (VALUE_LVAL (arg1) != lval_memory)
1370 error (_("Only values in memory can be extended with '@'."));
1371 if (count < 1)
1372 error (_("Invalid number %d of repetitions."), count);
1373
1374 val = allocate_repeat_value (value_enclosing_type (arg1), count);
1375
1376 read_memory (value_address (arg1),
1377 value_contents_all_raw (val),
1378 TYPE_LENGTH (value_enclosing_type (val)));
1379 VALUE_LVAL (val) = lval_memory;
1380 set_value_address (val, value_address (arg1));
1381
1382 return val;
1383 }
1384
1385 struct value *
1386 value_of_variable (struct symbol *var, struct block *b)
1387 {
1388 struct value *val;
1389 struct frame_info *frame;
1390
1391 if (!symbol_read_needs_frame (var))
1392 frame = NULL;
1393 else if (!b)
1394 frame = get_selected_frame (_("No frame selected."));
1395 else
1396 {
1397 frame = block_innermost_frame (b);
1398 if (!frame)
1399 {
1400 if (BLOCK_FUNCTION (b) && !block_inlined_p (b)
1401 && SYMBOL_PRINT_NAME (BLOCK_FUNCTION (b)))
1402 error (_("No frame is currently executing in block %s."),
1403 SYMBOL_PRINT_NAME (BLOCK_FUNCTION (b)));
1404 else
1405 error (_("No frame is currently executing in specified block"));
1406 }
1407 }
1408
1409 val = read_var_value (var, frame);
1410 if (!val)
1411 error (_("Address of symbol \"%s\" is unknown."), SYMBOL_PRINT_NAME (var));
1412
1413 return val;
1414 }
1415
1416 struct value *
1417 address_of_variable (struct symbol *var, struct block *b)
1418 {
1419 struct type *type = SYMBOL_TYPE (var);
1420 struct value *val;
1421
1422 /* Evaluate it first; if the result is a memory address, we're fine.
1423 Lazy evaluation pays off here. */
1424
1425 val = value_of_variable (var, b);
1426
1427 if ((VALUE_LVAL (val) == lval_memory && value_lazy (val))
1428 || TYPE_CODE (type) == TYPE_CODE_FUNC)
1429 {
1430 CORE_ADDR addr = value_address (val);
1431
1432 return value_from_pointer (lookup_pointer_type (type), addr);
1433 }
1434
1435 /* Not a memory address; check what the problem was. */
1436 switch (VALUE_LVAL (val))
1437 {
1438 case lval_register:
1439 {
1440 struct frame_info *frame;
1441 const char *regname;
1442
1443 frame = frame_find_by_id (VALUE_FRAME_ID (val));
1444 gdb_assert (frame);
1445
1446 regname = gdbarch_register_name (get_frame_arch (frame),
1447 VALUE_REGNUM (val));
1448 gdb_assert (regname && *regname);
1449
1450 error (_("Address requested for identifier "
1451 "\"%s\" which is in register $%s"),
1452 SYMBOL_PRINT_NAME (var), regname);
1453 break;
1454 }
1455
1456 default:
1457 error (_("Can't take address of \"%s\" which isn't an lvalue."),
1458 SYMBOL_PRINT_NAME (var));
1459 break;
1460 }
1461
1462 return val;
1463 }
1464
1465 /* Return one if VAL does not live in target memory, but should in order
1466 to operate on it. Otherwise return zero. */
1467
1468 int
1469 value_must_coerce_to_target (struct value *val)
1470 {
1471 struct type *valtype;
1472
1473 /* The only lval kinds which do not live in target memory. */
1474 if (VALUE_LVAL (val) != not_lval
1475 && VALUE_LVAL (val) != lval_internalvar)
1476 return 0;
1477
1478 valtype = check_typedef (value_type (val));
1479
1480 switch (TYPE_CODE (valtype))
1481 {
1482 case TYPE_CODE_ARRAY:
1483 return TYPE_VECTOR (valtype) ? 0 : 1;
1484 case TYPE_CODE_STRING:
1485 return 1;
1486 default:
1487 return 0;
1488 }
1489 }
1490
1491 /* Make sure that VAL lives in target memory if it's supposed to. For
1492 instance, strings are constructed as character arrays in GDB's
1493 storage, and this function copies them to the target. */
1494
1495 struct value *
1496 value_coerce_to_target (struct value *val)
1497 {
1498 LONGEST length;
1499 CORE_ADDR addr;
1500
1501 if (!value_must_coerce_to_target (val))
1502 return val;
1503
1504 length = TYPE_LENGTH (check_typedef (value_type (val)));
1505 addr = allocate_space_in_inferior (length);
1506 write_memory (addr, value_contents (val), length);
1507 return value_at_lazy (value_type (val), addr);
1508 }
1509
1510 /* Given a value which is an array, return a value which is a pointer
1511 to its first element, regardless of whether or not the array has a
1512 nonzero lower bound.
1513
1514 FIXME: A previous comment here indicated that this routine should
1515 be substracting the array's lower bound. It's not clear to me that
1516 this is correct. Given an array subscripting operation, it would
1517 certainly work to do the adjustment here, essentially computing:
1518
1519 (&array[0] - (lowerbound * sizeof array[0])) + (index * sizeof array[0])
1520
1521 However I believe a more appropriate and logical place to account
1522 for the lower bound is to do so in value_subscript, essentially
1523 computing:
1524
1525 (&array[0] + ((index - lowerbound) * sizeof array[0]))
1526
1527 As further evidence consider what would happen with operations
1528 other than array subscripting, where the caller would get back a
1529 value that had an address somewhere before the actual first element
1530 of the array, and the information about the lower bound would be
1531 lost because of the coercion to pointer type. */
1532
1533 struct value *
1534 value_coerce_array (struct value *arg1)
1535 {
1536 struct type *type = check_typedef (value_type (arg1));
1537
1538 /* If the user tries to do something requiring a pointer with an
1539 array that has not yet been pushed to the target, then this would
1540 be a good time to do so. */
1541 arg1 = value_coerce_to_target (arg1);
1542
1543 if (VALUE_LVAL (arg1) != lval_memory)
1544 error (_("Attempt to take address of value not located in memory."));
1545
1546 return value_from_pointer (lookup_pointer_type (TYPE_TARGET_TYPE (type)),
1547 value_address (arg1));
1548 }
1549
1550 /* Given a value which is a function, return a value which is a pointer
1551 to it. */
1552
1553 struct value *
1554 value_coerce_function (struct value *arg1)
1555 {
1556 struct value *retval;
1557
1558 if (VALUE_LVAL (arg1) != lval_memory)
1559 error (_("Attempt to take address of value not located in memory."));
1560
1561 retval = value_from_pointer (lookup_pointer_type (value_type (arg1)),
1562 value_address (arg1));
1563 return retval;
1564 }
1565
1566 /* Return a pointer value for the object for which ARG1 is the
1567 contents. */
1568
1569 struct value *
1570 value_addr (struct value *arg1)
1571 {
1572 struct value *arg2;
1573 struct type *type = check_typedef (value_type (arg1));
1574
1575 if (TYPE_CODE (type) == TYPE_CODE_REF)
1576 {
1577 /* Copy the value, but change the type from (T&) to (T*). We
1578 keep the same location information, which is efficient, and
1579 allows &(&X) to get the location containing the reference. */
1580 arg2 = value_copy (arg1);
1581 deprecated_set_value_type (arg2,
1582 lookup_pointer_type (TYPE_TARGET_TYPE (type)));
1583 return arg2;
1584 }
1585 if (TYPE_CODE (type) == TYPE_CODE_FUNC)
1586 return value_coerce_function (arg1);
1587
1588 /* If this is an array that has not yet been pushed to the target,
1589 then this would be a good time to force it to memory. */
1590 arg1 = value_coerce_to_target (arg1);
1591
1592 if (VALUE_LVAL (arg1) != lval_memory)
1593 error (_("Attempt to take address of value not located in memory."));
1594
1595 /* Get target memory address. */
1596 arg2 = value_from_pointer (lookup_pointer_type (value_type (arg1)),
1597 (value_address (arg1)
1598 + value_embedded_offset (arg1)));
1599
1600 /* This may be a pointer to a base subobject; so remember the
1601 full derived object's type ... */
1602 set_value_enclosing_type (arg2,
1603 lookup_pointer_type (value_enclosing_type (arg1)));
1604 /* ... and also the relative position of the subobject in the full
1605 object. */
1606 set_value_pointed_to_offset (arg2, value_embedded_offset (arg1));
1607 return arg2;
1608 }
1609
1610 /* Return a reference value for the object for which ARG1 is the
1611 contents. */
1612
1613 struct value *
1614 value_ref (struct value *arg1)
1615 {
1616 struct value *arg2;
1617 struct type *type = check_typedef (value_type (arg1));
1618
1619 if (TYPE_CODE (type) == TYPE_CODE_REF)
1620 return arg1;
1621
1622 arg2 = value_addr (arg1);
1623 deprecated_set_value_type (arg2, lookup_reference_type (type));
1624 return arg2;
1625 }
1626
1627 /* Given a value of a pointer type, apply the C unary * operator to
1628 it. */
1629
1630 struct value *
1631 value_ind (struct value *arg1)
1632 {
1633 struct type *base_type;
1634 struct value *arg2;
1635
1636 arg1 = coerce_array (arg1);
1637
1638 base_type = check_typedef (value_type (arg1));
1639
1640 if (VALUE_LVAL (arg1) == lval_computed)
1641 {
1642 struct lval_funcs *funcs = value_computed_funcs (arg1);
1643
1644 if (funcs->indirect)
1645 {
1646 struct value *result = funcs->indirect (arg1);
1647
1648 if (result)
1649 return result;
1650 }
1651 }
1652
1653 if (TYPE_CODE (base_type) == TYPE_CODE_PTR)
1654 {
1655 struct type *enc_type;
1656
1657 /* We may be pointing to something embedded in a larger object.
1658 Get the real type of the enclosing object. */
1659 enc_type = check_typedef (value_enclosing_type (arg1));
1660 enc_type = TYPE_TARGET_TYPE (enc_type);
1661
1662 if (TYPE_CODE (check_typedef (enc_type)) == TYPE_CODE_FUNC
1663 || TYPE_CODE (check_typedef (enc_type)) == TYPE_CODE_METHOD)
1664 /* For functions, go through find_function_addr, which knows
1665 how to handle function descriptors. */
1666 arg2 = value_at_lazy (enc_type,
1667 find_function_addr (arg1, NULL));
1668 else
1669 /* Retrieve the enclosing object pointed to. */
1670 arg2 = value_at_lazy (enc_type,
1671 (value_as_address (arg1)
1672 - value_pointed_to_offset (arg1)));
1673
1674 /* Re-adjust type. */
1675 deprecated_set_value_type (arg2, TYPE_TARGET_TYPE (base_type));
1676 /* Add embedding info. */
1677 set_value_enclosing_type (arg2, enc_type);
1678 set_value_embedded_offset (arg2, value_pointed_to_offset (arg1));
1679
1680 /* We may be pointing to an object of some derived type. */
1681 arg2 = value_full_object (arg2, NULL, 0, 0, 0);
1682 return arg2;
1683 }
1684
1685 error (_("Attempt to take contents of a non-pointer value."));
1686 return 0; /* For lint -- never reached. */
1687 }
1688 \f
1689 /* Create a value for an array by allocating space in GDB, copying
1690 copying the data into that space, and then setting up an array
1691 value.
1692
1693 The array bounds are set from LOWBOUND and HIGHBOUND, and the array
1694 is populated from the values passed in ELEMVEC.
1695
1696 The element type of the array is inherited from the type of the
1697 first element, and all elements must have the same size (though we
1698 don't currently enforce any restriction on their types). */
1699
1700 struct value *
1701 value_array (int lowbound, int highbound, struct value **elemvec)
1702 {
1703 int nelem;
1704 int idx;
1705 unsigned int typelength;
1706 struct value *val;
1707 struct type *arraytype;
1708
1709 /* Validate that the bounds are reasonable and that each of the
1710 elements have the same size. */
1711
1712 nelem = highbound - lowbound + 1;
1713 if (nelem <= 0)
1714 {
1715 error (_("bad array bounds (%d, %d)"), lowbound, highbound);
1716 }
1717 typelength = TYPE_LENGTH (value_enclosing_type (elemvec[0]));
1718 for (idx = 1; idx < nelem; idx++)
1719 {
1720 if (TYPE_LENGTH (value_enclosing_type (elemvec[idx])) != typelength)
1721 {
1722 error (_("array elements must all be the same size"));
1723 }
1724 }
1725
1726 arraytype = lookup_array_range_type (value_enclosing_type (elemvec[0]),
1727 lowbound, highbound);
1728
1729 if (!current_language->c_style_arrays)
1730 {
1731 val = allocate_value (arraytype);
1732 for (idx = 0; idx < nelem; idx++)
1733 {
1734 memcpy (value_contents_all_raw (val) + (idx * typelength),
1735 value_contents_all (elemvec[idx]),
1736 typelength);
1737 }
1738 return val;
1739 }
1740
1741 /* Allocate space to store the array, and then initialize it by
1742 copying in each element. */
1743
1744 val = allocate_value (arraytype);
1745 for (idx = 0; idx < nelem; idx++)
1746 memcpy (value_contents_writeable (val) + (idx * typelength),
1747 value_contents_all (elemvec[idx]),
1748 typelength);
1749 return val;
1750 }
1751
1752 struct value *
1753 value_cstring (char *ptr, int len, struct type *char_type)
1754 {
1755 struct value *val;
1756 int lowbound = current_language->string_lower_bound;
1757 int highbound = len / TYPE_LENGTH (char_type);
1758 struct type *stringtype
1759 = lookup_array_range_type (char_type, lowbound, highbound + lowbound - 1);
1760
1761 val = allocate_value (stringtype);
1762 memcpy (value_contents_raw (val), ptr, len);
1763 return val;
1764 }
1765
1766 /* Create a value for a string constant by allocating space in the
1767 inferior, copying the data into that space, and returning the
1768 address with type TYPE_CODE_STRING. PTR points to the string
1769 constant data; LEN is number of characters.
1770
1771 Note that string types are like array of char types with a lower
1772 bound of zero and an upper bound of LEN - 1. Also note that the
1773 string may contain embedded null bytes. */
1774
1775 struct value *
1776 value_string (char *ptr, int len, struct type *char_type)
1777 {
1778 struct value *val;
1779 int lowbound = current_language->string_lower_bound;
1780 int highbound = len / TYPE_LENGTH (char_type);
1781 struct type *stringtype
1782 = lookup_string_range_type (char_type, lowbound, highbound + lowbound - 1);
1783
1784 val = allocate_value (stringtype);
1785 memcpy (value_contents_raw (val), ptr, len);
1786 return val;
1787 }
1788
1789 struct value *
1790 value_bitstring (char *ptr, int len, struct type *index_type)
1791 {
1792 struct value *val;
1793 struct type *domain_type
1794 = create_range_type (NULL, index_type, 0, len - 1);
1795 struct type *type = create_set_type (NULL, domain_type);
1796
1797 TYPE_CODE (type) = TYPE_CODE_BITSTRING;
1798 val = allocate_value (type);
1799 memcpy (value_contents_raw (val), ptr, TYPE_LENGTH (type));
1800 return val;
1801 }
1802 \f
1803 /* See if we can pass arguments in T2 to a function which takes
1804 arguments of types T1. T1 is a list of NARGS arguments, and T2 is
1805 a NULL-terminated vector. If some arguments need coercion of some
1806 sort, then the coerced values are written into T2. Return value is
1807 0 if the arguments could be matched, or the position at which they
1808 differ if not.
1809
1810 STATICP is nonzero if the T1 argument list came from a static
1811 member function. T2 will still include the ``this'' pointer, but
1812 it will be skipped.
1813
1814 For non-static member functions, we ignore the first argument,
1815 which is the type of the instance variable. This is because we
1816 want to handle calls with objects from derived classes. This is
1817 not entirely correct: we should actually check to make sure that a
1818 requested operation is type secure, shouldn't we? FIXME. */
1819
1820 static int
1821 typecmp (int staticp, int varargs, int nargs,
1822 struct field t1[], struct value *t2[])
1823 {
1824 int i;
1825
1826 if (t2 == 0)
1827 internal_error (__FILE__, __LINE__,
1828 _("typecmp: no argument list"));
1829
1830 /* Skip ``this'' argument if applicable. T2 will always include
1831 THIS. */
1832 if (staticp)
1833 t2 ++;
1834
1835 for (i = 0;
1836 (i < nargs) && TYPE_CODE (t1[i].type) != TYPE_CODE_VOID;
1837 i++)
1838 {
1839 struct type *tt1, *tt2;
1840
1841 if (!t2[i])
1842 return i + 1;
1843
1844 tt1 = check_typedef (t1[i].type);
1845 tt2 = check_typedef (value_type (t2[i]));
1846
1847 if (TYPE_CODE (tt1) == TYPE_CODE_REF
1848 /* We should be doing hairy argument matching, as below. */
1849 && (TYPE_CODE (check_typedef (TYPE_TARGET_TYPE (tt1)))
1850 == TYPE_CODE (tt2)))
1851 {
1852 if (TYPE_CODE (tt2) == TYPE_CODE_ARRAY)
1853 t2[i] = value_coerce_array (t2[i]);
1854 else
1855 t2[i] = value_ref (t2[i]);
1856 continue;
1857 }
1858
1859 /* djb - 20000715 - Until the new type structure is in the
1860 place, and we can attempt things like implicit conversions,
1861 we need to do this so you can take something like a map<const
1862 char *>, and properly access map["hello"], because the
1863 argument to [] will be a reference to a pointer to a char,
1864 and the argument will be a pointer to a char. */
1865 while (TYPE_CODE(tt1) == TYPE_CODE_REF
1866 || TYPE_CODE (tt1) == TYPE_CODE_PTR)
1867 {
1868 tt1 = check_typedef( TYPE_TARGET_TYPE(tt1) );
1869 }
1870 while (TYPE_CODE(tt2) == TYPE_CODE_ARRAY
1871 || TYPE_CODE(tt2) == TYPE_CODE_PTR
1872 || TYPE_CODE(tt2) == TYPE_CODE_REF)
1873 {
1874 tt2 = check_typedef (TYPE_TARGET_TYPE(tt2));
1875 }
1876 if (TYPE_CODE (tt1) == TYPE_CODE (tt2))
1877 continue;
1878 /* Array to pointer is a `trivial conversion' according to the
1879 ARM. */
1880
1881 /* We should be doing much hairier argument matching (see
1882 section 13.2 of the ARM), but as a quick kludge, just check
1883 for the same type code. */
1884 if (TYPE_CODE (t1[i].type) != TYPE_CODE (value_type (t2[i])))
1885 return i + 1;
1886 }
1887 if (varargs || t2[i] == NULL)
1888 return 0;
1889 return i + 1;
1890 }
1891
1892 /* Helper function used by value_struct_elt to recurse through
1893 baseclasses. Look for a field NAME in ARG1. Adjust the address of
1894 ARG1 by OFFSET bytes, and search in it assuming it has (class) type
1895 TYPE. If found, return value, else return NULL.
1896
1897 If LOOKING_FOR_BASECLASS, then instead of looking for struct
1898 fields, look for a baseclass named NAME. */
1899
1900 static struct value *
1901 search_struct_field (const char *name, struct value *arg1, int offset,
1902 struct type *type, int looking_for_baseclass)
1903 {
1904 int i;
1905 int nbases;
1906
1907 CHECK_TYPEDEF (type);
1908 nbases = TYPE_N_BASECLASSES (type);
1909
1910 if (!looking_for_baseclass)
1911 for (i = TYPE_NFIELDS (type) - 1; i >= nbases; i--)
1912 {
1913 char *t_field_name = TYPE_FIELD_NAME (type, i);
1914
1915 if (t_field_name && (strcmp_iw (t_field_name, name) == 0))
1916 {
1917 struct value *v;
1918
1919 if (field_is_static (&TYPE_FIELD (type, i)))
1920 {
1921 v = value_static_field (type, i);
1922 if (v == 0)
1923 error (_("field %s is nonexistent or "
1924 "has been optimized out"),
1925 name);
1926 }
1927 else
1928 {
1929 v = value_primitive_field (arg1, offset, i, type);
1930 if (v == 0)
1931 error (_("there is no field named %s"), name);
1932 }
1933 return v;
1934 }
1935
1936 if (t_field_name
1937 && (t_field_name[0] == '\0'
1938 || (TYPE_CODE (type) == TYPE_CODE_UNION
1939 && (strcmp_iw (t_field_name, "else") == 0))))
1940 {
1941 struct type *field_type = TYPE_FIELD_TYPE (type, i);
1942
1943 if (TYPE_CODE (field_type) == TYPE_CODE_UNION
1944 || TYPE_CODE (field_type) == TYPE_CODE_STRUCT)
1945 {
1946 /* Look for a match through the fields of an anonymous
1947 union, or anonymous struct. C++ provides anonymous
1948 unions.
1949
1950 In the GNU Chill (now deleted from GDB)
1951 implementation of variant record types, each
1952 <alternative field> has an (anonymous) union type,
1953 each member of the union represents a <variant
1954 alternative>. Each <variant alternative> is
1955 represented as a struct, with a member for each
1956 <variant field>. */
1957
1958 struct value *v;
1959 int new_offset = offset;
1960
1961 /* This is pretty gross. In G++, the offset in an
1962 anonymous union is relative to the beginning of the
1963 enclosing struct. In the GNU Chill (now deleted
1964 from GDB) implementation of variant records, the
1965 bitpos is zero in an anonymous union field, so we
1966 have to add the offset of the union here. */
1967 if (TYPE_CODE (field_type) == TYPE_CODE_STRUCT
1968 || (TYPE_NFIELDS (field_type) > 0
1969 && TYPE_FIELD_BITPOS (field_type, 0) == 0))
1970 new_offset += TYPE_FIELD_BITPOS (type, i) / 8;
1971
1972 v = search_struct_field (name, arg1, new_offset,
1973 field_type,
1974 looking_for_baseclass);
1975 if (v)
1976 return v;
1977 }
1978 }
1979 }
1980
1981 for (i = 0; i < nbases; i++)
1982 {
1983 struct value *v;
1984 struct type *basetype = check_typedef (TYPE_BASECLASS (type, i));
1985 /* If we are looking for baseclasses, this is what we get when
1986 we hit them. But it could happen that the base part's member
1987 name is not yet filled in. */
1988 int found_baseclass = (looking_for_baseclass
1989 && TYPE_BASECLASS_NAME (type, i) != NULL
1990 && (strcmp_iw (name,
1991 TYPE_BASECLASS_NAME (type,
1992 i)) == 0));
1993
1994 if (BASETYPE_VIA_VIRTUAL (type, i))
1995 {
1996 int boffset;
1997 struct value *v2;
1998
1999 boffset = baseclass_offset (type, i,
2000 value_contents (arg1) + offset,
2001 value_address (arg1)
2002 + value_embedded_offset (arg1)
2003 + offset);
2004 if (boffset == -1)
2005 error (_("virtual baseclass botch"));
2006
2007 /* The virtual base class pointer might have been clobbered
2008 by the user program. Make sure that it still points to a
2009 valid memory location. */
2010
2011 boffset += value_embedded_offset (arg1) + offset;
2012 if (boffset < 0
2013 || boffset >= TYPE_LENGTH (value_enclosing_type (arg1)))
2014 {
2015 CORE_ADDR base_addr;
2016
2017 v2 = allocate_value (basetype);
2018 base_addr = value_address (arg1) + boffset;
2019 if (target_read_memory (base_addr,
2020 value_contents_raw (v2),
2021 TYPE_LENGTH (basetype)) != 0)
2022 error (_("virtual baseclass botch"));
2023 VALUE_LVAL (v2) = lval_memory;
2024 set_value_address (v2, base_addr);
2025 }
2026 else
2027 {
2028 v2 = value_copy (arg1);
2029 deprecated_set_value_type (v2, basetype);
2030 set_value_embedded_offset (v2, boffset);
2031 }
2032
2033 if (found_baseclass)
2034 return v2;
2035 v = search_struct_field (name, v2, 0,
2036 TYPE_BASECLASS (type, i),
2037 looking_for_baseclass);
2038 }
2039 else if (found_baseclass)
2040 v = value_primitive_field (arg1, offset, i, type);
2041 else
2042 v = search_struct_field (name, arg1,
2043 offset + TYPE_BASECLASS_BITPOS (type,
2044 i) / 8,
2045 basetype, looking_for_baseclass);
2046 if (v)
2047 return v;
2048 }
2049 return NULL;
2050 }
2051
2052 /* Helper function used by value_struct_elt to recurse through
2053 baseclasses. Look for a field NAME in ARG1. Adjust the address of
2054 ARG1 by OFFSET bytes, and search in it assuming it has (class) type
2055 TYPE.
2056
2057 If found, return value, else if name matched and args not return
2058 (value) -1, else return NULL. */
2059
2060 static struct value *
2061 search_struct_method (const char *name, struct value **arg1p,
2062 struct value **args, int offset,
2063 int *static_memfuncp, struct type *type)
2064 {
2065 int i;
2066 struct value *v;
2067 int name_matched = 0;
2068 char dem_opname[64];
2069
2070 CHECK_TYPEDEF (type);
2071 for (i = TYPE_NFN_FIELDS (type) - 1; i >= 0; i--)
2072 {
2073 char *t_field_name = TYPE_FN_FIELDLIST_NAME (type, i);
2074
2075 /* FIXME! May need to check for ARM demangling here. */
2076 if (strncmp (t_field_name, "__", 2) == 0 ||
2077 strncmp (t_field_name, "op", 2) == 0 ||
2078 strncmp (t_field_name, "type", 4) == 0)
2079 {
2080 if (cplus_demangle_opname (t_field_name, dem_opname, DMGL_ANSI))
2081 t_field_name = dem_opname;
2082 else if (cplus_demangle_opname (t_field_name, dem_opname, 0))
2083 t_field_name = dem_opname;
2084 }
2085 if (t_field_name && (strcmp_iw (t_field_name, name) == 0))
2086 {
2087 int j = TYPE_FN_FIELDLIST_LENGTH (type, i) - 1;
2088 struct fn_field *f = TYPE_FN_FIELDLIST1 (type, i);
2089
2090 name_matched = 1;
2091 check_stub_method_group (type, i);
2092 if (j > 0 && args == 0)
2093 error (_("cannot resolve overloaded method "
2094 "`%s': no arguments supplied"), name);
2095 else if (j == 0 && args == 0)
2096 {
2097 v = value_fn_field (arg1p, f, j, type, offset);
2098 if (v != NULL)
2099 return v;
2100 }
2101 else
2102 while (j >= 0)
2103 {
2104 if (!typecmp (TYPE_FN_FIELD_STATIC_P (f, j),
2105 TYPE_VARARGS (TYPE_FN_FIELD_TYPE (f, j)),
2106 TYPE_NFIELDS (TYPE_FN_FIELD_TYPE (f, j)),
2107 TYPE_FN_FIELD_ARGS (f, j), args))
2108 {
2109 if (TYPE_FN_FIELD_VIRTUAL_P (f, j))
2110 return value_virtual_fn_field (arg1p, f, j,
2111 type, offset);
2112 if (TYPE_FN_FIELD_STATIC_P (f, j)
2113 && static_memfuncp)
2114 *static_memfuncp = 1;
2115 v = value_fn_field (arg1p, f, j, type, offset);
2116 if (v != NULL)
2117 return v;
2118 }
2119 j--;
2120 }
2121 }
2122 }
2123
2124 for (i = TYPE_N_BASECLASSES (type) - 1; i >= 0; i--)
2125 {
2126 int base_offset;
2127
2128 if (BASETYPE_VIA_VIRTUAL (type, i))
2129 {
2130 struct type *baseclass = check_typedef (TYPE_BASECLASS (type, i));
2131 const gdb_byte *base_valaddr;
2132
2133 /* The virtual base class pointer might have been
2134 clobbered by the user program. Make sure that it
2135 still points to a valid memory location. */
2136
2137 if (offset < 0 || offset >= TYPE_LENGTH (type))
2138 {
2139 gdb_byte *tmp = alloca (TYPE_LENGTH (baseclass));
2140
2141 if (target_read_memory (value_address (*arg1p) + offset,
2142 tmp, TYPE_LENGTH (baseclass)) != 0)
2143 error (_("virtual baseclass botch"));
2144 base_valaddr = tmp;
2145 }
2146 else
2147 base_valaddr = value_contents (*arg1p) + offset;
2148
2149 base_offset = baseclass_offset (type, i, base_valaddr,
2150 value_address (*arg1p) + offset);
2151 if (base_offset == -1)
2152 error (_("virtual baseclass botch"));
2153 }
2154 else
2155 {
2156 base_offset = TYPE_BASECLASS_BITPOS (type, i) / 8;
2157 }
2158 v = search_struct_method (name, arg1p, args, base_offset + offset,
2159 static_memfuncp, TYPE_BASECLASS (type, i));
2160 if (v == (struct value *) - 1)
2161 {
2162 name_matched = 1;
2163 }
2164 else if (v)
2165 {
2166 /* FIXME-bothner: Why is this commented out? Why is it here? */
2167 /* *arg1p = arg1_tmp; */
2168 return v;
2169 }
2170 }
2171 if (name_matched)
2172 return (struct value *) - 1;
2173 else
2174 return NULL;
2175 }
2176
2177 /* Given *ARGP, a value of type (pointer to a)* structure/union,
2178 extract the component named NAME from the ultimate target
2179 structure/union and return it as a value with its appropriate type.
2180 ERR is used in the error message if *ARGP's type is wrong.
2181
2182 C++: ARGS is a list of argument types to aid in the selection of
2183 an appropriate method. Also, handle derived types.
2184
2185 STATIC_MEMFUNCP, if non-NULL, points to a caller-supplied location
2186 where the truthvalue of whether the function that was resolved was
2187 a static member function or not is stored.
2188
2189 ERR is an error message to be printed in case the field is not
2190 found. */
2191
2192 struct value *
2193 value_struct_elt (struct value **argp, struct value **args,
2194 const char *name, int *static_memfuncp, const char *err)
2195 {
2196 struct type *t;
2197 struct value *v;
2198
2199 *argp = coerce_array (*argp);
2200
2201 t = check_typedef (value_type (*argp));
2202
2203 /* Follow pointers until we get to a non-pointer. */
2204
2205 while (TYPE_CODE (t) == TYPE_CODE_PTR || TYPE_CODE (t) == TYPE_CODE_REF)
2206 {
2207 *argp = value_ind (*argp);
2208 /* Don't coerce fn pointer to fn and then back again! */
2209 if (TYPE_CODE (value_type (*argp)) != TYPE_CODE_FUNC)
2210 *argp = coerce_array (*argp);
2211 t = check_typedef (value_type (*argp));
2212 }
2213
2214 if (TYPE_CODE (t) != TYPE_CODE_STRUCT
2215 && TYPE_CODE (t) != TYPE_CODE_UNION)
2216 error (_("Attempt to extract a component of a value that is not a %s."),
2217 err);
2218
2219 /* Assume it's not, unless we see that it is. */
2220 if (static_memfuncp)
2221 *static_memfuncp = 0;
2222
2223 if (!args)
2224 {
2225 /* if there are no arguments ...do this... */
2226
2227 /* Try as a field first, because if we succeed, there is less
2228 work to be done. */
2229 v = search_struct_field (name, *argp, 0, t, 0);
2230 if (v)
2231 return v;
2232
2233 /* C++: If it was not found as a data field, then try to
2234 return it as a pointer to a method. */
2235 v = search_struct_method (name, argp, args, 0,
2236 static_memfuncp, t);
2237
2238 if (v == (struct value *) - 1)
2239 error (_("Cannot take address of method %s."), name);
2240 else if (v == 0)
2241 {
2242 if (TYPE_NFN_FIELDS (t))
2243 error (_("There is no member or method named %s."), name);
2244 else
2245 error (_("There is no member named %s."), name);
2246 }
2247 return v;
2248 }
2249
2250 v = search_struct_method (name, argp, args, 0,
2251 static_memfuncp, t);
2252
2253 if (v == (struct value *) - 1)
2254 {
2255 error (_("One of the arguments you tried to pass to %s could not "
2256 "be converted to what the function wants."), name);
2257 }
2258 else if (v == 0)
2259 {
2260 /* See if user tried to invoke data as function. If so, hand it
2261 back. If it's not callable (i.e., a pointer to function),
2262 gdb should give an error. */
2263 v = search_struct_field (name, *argp, 0, t, 0);
2264 /* If we found an ordinary field, then it is not a method call.
2265 So, treat it as if it were a static member function. */
2266 if (v && static_memfuncp)
2267 *static_memfuncp = 1;
2268 }
2269
2270 if (!v)
2271 throw_error (NOT_FOUND_ERROR,
2272 _("Structure has no component named %s."), name);
2273 return v;
2274 }
2275
2276 /* Search through the methods of an object (and its bases) to find a
2277 specified method. Return the pointer to the fn_field list of
2278 overloaded instances.
2279
2280 Helper function for value_find_oload_list.
2281 ARGP is a pointer to a pointer to a value (the object).
2282 METHOD is a string containing the method name.
2283 OFFSET is the offset within the value.
2284 TYPE is the assumed type of the object.
2285 NUM_FNS is the number of overloaded instances.
2286 BASETYPE is set to the actual type of the subobject where the
2287 method is found.
2288 BOFFSET is the offset of the base subobject where the method is found. */
2289
2290 static struct fn_field *
2291 find_method_list (struct value **argp, const char *method,
2292 int offset, struct type *type, int *num_fns,
2293 struct type **basetype, int *boffset)
2294 {
2295 int i;
2296 struct fn_field *f;
2297 CHECK_TYPEDEF (type);
2298
2299 *num_fns = 0;
2300
2301 /* First check in object itself. */
2302 for (i = TYPE_NFN_FIELDS (type) - 1; i >= 0; i--)
2303 {
2304 /* pai: FIXME What about operators and type conversions? */
2305 char *fn_field_name = TYPE_FN_FIELDLIST_NAME (type, i);
2306
2307 if (fn_field_name && (strcmp_iw (fn_field_name, method) == 0))
2308 {
2309 int len = TYPE_FN_FIELDLIST_LENGTH (type, i);
2310 struct fn_field *f = TYPE_FN_FIELDLIST1 (type, i);
2311
2312 *num_fns = len;
2313 *basetype = type;
2314 *boffset = offset;
2315
2316 /* Resolve any stub methods. */
2317 check_stub_method_group (type, i);
2318
2319 return f;
2320 }
2321 }
2322
2323 /* Not found in object, check in base subobjects. */
2324 for (i = TYPE_N_BASECLASSES (type) - 1; i >= 0; i--)
2325 {
2326 int base_offset;
2327
2328 if (BASETYPE_VIA_VIRTUAL (type, i))
2329 {
2330 base_offset = value_offset (*argp) + offset;
2331 base_offset = baseclass_offset (type, i,
2332 value_contents (*argp) + base_offset,
2333 value_address (*argp) + base_offset);
2334 if (base_offset == -1)
2335 error (_("virtual baseclass botch"));
2336 }
2337 else /* Non-virtual base, simply use bit position from debug
2338 info. */
2339 {
2340 base_offset = TYPE_BASECLASS_BITPOS (type, i) / 8;
2341 }
2342 f = find_method_list (argp, method, base_offset + offset,
2343 TYPE_BASECLASS (type, i), num_fns,
2344 basetype, boffset);
2345 if (f)
2346 return f;
2347 }
2348 return NULL;
2349 }
2350
2351 /* Return the list of overloaded methods of a specified name.
2352
2353 ARGP is a pointer to a pointer to a value (the object).
2354 METHOD is the method name.
2355 OFFSET is the offset within the value contents.
2356 NUM_FNS is the number of overloaded instances.
2357 BASETYPE is set to the type of the base subobject that defines the
2358 method.
2359 BOFFSET is the offset of the base subobject which defines the method. */
2360
2361 struct fn_field *
2362 value_find_oload_method_list (struct value **argp, const char *method,
2363 int offset, int *num_fns,
2364 struct type **basetype, int *boffset)
2365 {
2366 struct type *t;
2367
2368 t = check_typedef (value_type (*argp));
2369
2370 /* Code snarfed from value_struct_elt. */
2371 while (TYPE_CODE (t) == TYPE_CODE_PTR || TYPE_CODE (t) == TYPE_CODE_REF)
2372 {
2373 *argp = value_ind (*argp);
2374 /* Don't coerce fn pointer to fn and then back again! */
2375 if (TYPE_CODE (value_type (*argp)) != TYPE_CODE_FUNC)
2376 *argp = coerce_array (*argp);
2377 t = check_typedef (value_type (*argp));
2378 }
2379
2380 if (TYPE_CODE (t) != TYPE_CODE_STRUCT
2381 && TYPE_CODE (t) != TYPE_CODE_UNION)
2382 error (_("Attempt to extract a component of a "
2383 "value that is not a struct or union"));
2384
2385 return find_method_list (argp, method, 0, t, num_fns,
2386 basetype, boffset);
2387 }
2388
2389 /* Given an array of argument types (ARGTYPES) (which includes an
2390 entry for "this" in the case of C++ methods), the number of
2391 arguments NARGS, the NAME of a function whether it's a method or
2392 not (METHOD), and the degree of laxness (LAX) in conforming to
2393 overload resolution rules in ANSI C++, find the best function that
2394 matches on the argument types according to the overload resolution
2395 rules.
2396
2397 METHOD can be one of three values:
2398 NON_METHOD for non-member functions.
2399 METHOD: for member functions.
2400 BOTH: used for overload resolution of operators where the
2401 candidates are expected to be either member or non member
2402 functions. In this case the first argument ARGTYPES
2403 (representing 'this') is expected to be a reference to the
2404 target object, and will be dereferenced when attempting the
2405 non-member search.
2406
2407 In the case of class methods, the parameter OBJ is an object value
2408 in which to search for overloaded methods.
2409
2410 In the case of non-method functions, the parameter FSYM is a symbol
2411 corresponding to one of the overloaded functions.
2412
2413 Return value is an integer: 0 -> good match, 10 -> debugger applied
2414 non-standard coercions, 100 -> incompatible.
2415
2416 If a method is being searched for, VALP will hold the value.
2417 If a non-method is being searched for, SYMP will hold the symbol
2418 for it.
2419
2420 If a method is being searched for, and it is a static method,
2421 then STATICP will point to a non-zero value.
2422
2423 If NO_ADL argument dependent lookup is disabled. This is used to prevent
2424 ADL overload candidates when performing overload resolution for a fully
2425 qualified name.
2426
2427 Note: This function does *not* check the value of
2428 overload_resolution. Caller must check it to see whether overload
2429 resolution is permitted. */
2430
2431 int
2432 find_overload_match (struct type **arg_types, int nargs,
2433 const char *name, enum oload_search_type method,
2434 int lax, struct value **objp, struct symbol *fsym,
2435 struct value **valp, struct symbol **symp,
2436 int *staticp, const int no_adl)
2437 {
2438 struct value *obj = (objp ? *objp : NULL);
2439 /* Index of best overloaded function. */
2440 int func_oload_champ = -1;
2441 int method_oload_champ = -1;
2442
2443 /* The measure for the current best match. */
2444 struct badness_vector *method_badness = NULL;
2445 struct badness_vector *func_badness = NULL;
2446
2447 struct value *temp = obj;
2448 /* For methods, the list of overloaded methods. */
2449 struct fn_field *fns_ptr = NULL;
2450 /* For non-methods, the list of overloaded function symbols. */
2451 struct symbol **oload_syms = NULL;
2452 /* Number of overloaded instances being considered. */
2453 int num_fns = 0;
2454 struct type *basetype = NULL;
2455 int boffset;
2456
2457 struct cleanup *all_cleanups = make_cleanup (null_cleanup, NULL);
2458
2459 const char *obj_type_name = NULL;
2460 const char *func_name = NULL;
2461 enum oload_classification match_quality;
2462 enum oload_classification method_match_quality = INCOMPATIBLE;
2463 enum oload_classification func_match_quality = INCOMPATIBLE;
2464
2465 /* Get the list of overloaded methods or functions. */
2466 if (method == METHOD || method == BOTH)
2467 {
2468 gdb_assert (obj);
2469
2470 /* OBJ may be a pointer value rather than the object itself. */
2471 obj = coerce_ref (obj);
2472 while (TYPE_CODE (check_typedef (value_type (obj))) == TYPE_CODE_PTR)
2473 obj = coerce_ref (value_ind (obj));
2474 obj_type_name = TYPE_NAME (value_type (obj));
2475
2476 /* First check whether this is a data member, e.g. a pointer to
2477 a function. */
2478 if (TYPE_CODE (check_typedef (value_type (obj))) == TYPE_CODE_STRUCT)
2479 {
2480 *valp = search_struct_field (name, obj, 0,
2481 check_typedef (value_type (obj)), 0);
2482 if (*valp)
2483 {
2484 *staticp = 1;
2485 return 0;
2486 }
2487 }
2488
2489 /* Retrieve the list of methods with the name NAME. */
2490 fns_ptr = value_find_oload_method_list (&temp, name,
2491 0, &num_fns,
2492 &basetype, &boffset);
2493 /* If this is a method only search, and no methods were found
2494 the search has faild. */
2495 if (method == METHOD && (!fns_ptr || !num_fns))
2496 error (_("Couldn't find method %s%s%s"),
2497 obj_type_name,
2498 (obj_type_name && *obj_type_name) ? "::" : "",
2499 name);
2500 /* If we are dealing with stub method types, they should have
2501 been resolved by find_method_list via
2502 value_find_oload_method_list above. */
2503 if (fns_ptr)
2504 {
2505 gdb_assert (TYPE_DOMAIN_TYPE (fns_ptr[0].type) != NULL);
2506 method_oload_champ = find_oload_champ (arg_types, nargs, method,
2507 num_fns, fns_ptr,
2508 oload_syms, &method_badness);
2509
2510 method_match_quality =
2511 classify_oload_match (method_badness, nargs,
2512 oload_method_static (method, fns_ptr,
2513 method_oload_champ));
2514
2515 make_cleanup (xfree, method_badness);
2516 }
2517
2518 }
2519
2520 if (method == NON_METHOD || method == BOTH)
2521 {
2522 const char *qualified_name = NULL;
2523
2524 /* If the the overload match is being search for both
2525 as a method and non member function, the first argument
2526 must now be dereferenced. */
2527 if (method == BOTH)
2528 arg_types[0] = TYPE_TARGET_TYPE (arg_types[0]);
2529
2530 if (fsym)
2531 {
2532 qualified_name = SYMBOL_NATURAL_NAME (fsym);
2533
2534 /* If we have a function with a C++ name, try to extract just
2535 the function part. Do not try this for non-functions (e.g.
2536 function pointers). */
2537 if (qualified_name
2538 && TYPE_CODE (check_typedef (SYMBOL_TYPE (fsym)))
2539 == TYPE_CODE_FUNC)
2540 {
2541 char *temp;
2542
2543 temp = cp_func_name (qualified_name);
2544
2545 /* If cp_func_name did not remove anything, the name of the
2546 symbol did not include scope or argument types - it was
2547 probably a C-style function. */
2548 if (temp)
2549 {
2550 make_cleanup (xfree, temp);
2551 if (strcmp (temp, qualified_name) == 0)
2552 func_name = NULL;
2553 else
2554 func_name = temp;
2555 }
2556 }
2557 }
2558 else
2559 {
2560 func_name = name;
2561 qualified_name = name;
2562 }
2563
2564 /* If there was no C++ name, this must be a C-style function or
2565 not a function at all. Just return the same symbol. Do the
2566 same if cp_func_name fails for some reason. */
2567 if (func_name == NULL)
2568 {
2569 *symp = fsym;
2570 return 0;
2571 }
2572
2573 func_oload_champ = find_oload_champ_namespace (arg_types, nargs,
2574 func_name,
2575 qualified_name,
2576 &oload_syms,
2577 &func_badness,
2578 no_adl);
2579
2580 if (func_oload_champ >= 0)
2581 func_match_quality = classify_oload_match (func_badness, nargs, 0);
2582
2583 make_cleanup (xfree, oload_syms);
2584 make_cleanup (xfree, func_badness);
2585 }
2586
2587 /* Did we find a match ? */
2588 if (method_oload_champ == -1 && func_oload_champ == -1)
2589 throw_error (NOT_FOUND_ERROR,
2590 _("No symbol \"%s\" in current context."),
2591 name);
2592
2593 /* If we have found both a method match and a function
2594 match, find out which one is better, and calculate match
2595 quality. */
2596 if (method_oload_champ >= 0 && func_oload_champ >= 0)
2597 {
2598 switch (compare_badness (func_badness, method_badness))
2599 {
2600 case 0: /* Top two contenders are equally good. */
2601 /* FIXME: GDB does not support the general ambiguous
2602 case. All candidates should be collected and presented
2603 the the user. */
2604 error (_("Ambiguous overload resolution"));
2605 break;
2606 case 1: /* Incomparable top contenders. */
2607 /* This is an error incompatible candidates
2608 should not have been proposed. */
2609 error (_("Internal error: incompatible "
2610 "overload candidates proposed"));
2611 break;
2612 case 2: /* Function champion. */
2613 method_oload_champ = -1;
2614 match_quality = func_match_quality;
2615 break;
2616 case 3: /* Method champion. */
2617 func_oload_champ = -1;
2618 match_quality = method_match_quality;
2619 break;
2620 default:
2621 error (_("Internal error: unexpected overload comparison result"));
2622 break;
2623 }
2624 }
2625 else
2626 {
2627 /* We have either a method match or a function match. */
2628 if (method_oload_champ >= 0)
2629 match_quality = method_match_quality;
2630 else
2631 match_quality = func_match_quality;
2632 }
2633
2634 if (match_quality == INCOMPATIBLE)
2635 {
2636 if (method == METHOD)
2637 error (_("Cannot resolve method %s%s%s to any overloaded instance"),
2638 obj_type_name,
2639 (obj_type_name && *obj_type_name) ? "::" : "",
2640 name);
2641 else
2642 error (_("Cannot resolve function %s to any overloaded instance"),
2643 func_name);
2644 }
2645 else if (match_quality == NON_STANDARD)
2646 {
2647 if (method == METHOD)
2648 warning (_("Using non-standard conversion to match "
2649 "method %s%s%s to supplied arguments"),
2650 obj_type_name,
2651 (obj_type_name && *obj_type_name) ? "::" : "",
2652 name);
2653 else
2654 warning (_("Using non-standard conversion to match "
2655 "function %s to supplied arguments"),
2656 func_name);
2657 }
2658
2659 if (staticp != NULL)
2660 *staticp = oload_method_static (method, fns_ptr, method_oload_champ);
2661
2662 if (method_oload_champ >= 0)
2663 {
2664 if (TYPE_FN_FIELD_VIRTUAL_P (fns_ptr, method_oload_champ))
2665 *valp = value_virtual_fn_field (&temp, fns_ptr, method_oload_champ,
2666 basetype, boffset);
2667 else
2668 *valp = value_fn_field (&temp, fns_ptr, method_oload_champ,
2669 basetype, boffset);
2670 }
2671 else
2672 *symp = oload_syms[func_oload_champ];
2673
2674 if (objp)
2675 {
2676 struct type *temp_type = check_typedef (value_type (temp));
2677 struct type *obj_type = check_typedef (value_type (*objp));
2678
2679 if (TYPE_CODE (temp_type) != TYPE_CODE_PTR
2680 && (TYPE_CODE (obj_type) == TYPE_CODE_PTR
2681 || TYPE_CODE (obj_type) == TYPE_CODE_REF))
2682 {
2683 temp = value_addr (temp);
2684 }
2685 *objp = temp;
2686 }
2687
2688 do_cleanups (all_cleanups);
2689
2690 switch (match_quality)
2691 {
2692 case INCOMPATIBLE:
2693 return 100;
2694 case NON_STANDARD:
2695 return 10;
2696 default: /* STANDARD */
2697 return 0;
2698 }
2699 }
2700
2701 /* Find the best overload match, searching for FUNC_NAME in namespaces
2702 contained in QUALIFIED_NAME until it either finds a good match or
2703 runs out of namespaces. It stores the overloaded functions in
2704 *OLOAD_SYMS, and the badness vector in *OLOAD_CHAMP_BV. The
2705 calling function is responsible for freeing *OLOAD_SYMS and
2706 *OLOAD_CHAMP_BV. If NO_ADL, argument dependent lookup is not
2707 performned. */
2708
2709 static int
2710 find_oload_champ_namespace (struct type **arg_types, int nargs,
2711 const char *func_name,
2712 const char *qualified_name,
2713 struct symbol ***oload_syms,
2714 struct badness_vector **oload_champ_bv,
2715 const int no_adl)
2716 {
2717 int oload_champ;
2718
2719 find_oload_champ_namespace_loop (arg_types, nargs,
2720 func_name,
2721 qualified_name, 0,
2722 oload_syms, oload_champ_bv,
2723 &oload_champ,
2724 no_adl);
2725
2726 return oload_champ;
2727 }
2728
2729 /* Helper function for find_oload_champ_namespace; NAMESPACE_LEN is
2730 how deep we've looked for namespaces, and the champ is stored in
2731 OLOAD_CHAMP. The return value is 1 if the champ is a good one, 0
2732 if it isn't. Other arguments are the same as in
2733 find_oload_champ_namespace
2734
2735 It is the caller's responsibility to free *OLOAD_SYMS and
2736 *OLOAD_CHAMP_BV. */
2737
2738 static int
2739 find_oload_champ_namespace_loop (struct type **arg_types, int nargs,
2740 const char *func_name,
2741 const char *qualified_name,
2742 int namespace_len,
2743 struct symbol ***oload_syms,
2744 struct badness_vector **oload_champ_bv,
2745 int *oload_champ,
2746 const int no_adl)
2747 {
2748 int next_namespace_len = namespace_len;
2749 int searched_deeper = 0;
2750 int num_fns = 0;
2751 struct cleanup *old_cleanups;
2752 int new_oload_champ;
2753 struct symbol **new_oload_syms;
2754 struct badness_vector *new_oload_champ_bv;
2755 char *new_namespace;
2756
2757 if (next_namespace_len != 0)
2758 {
2759 gdb_assert (qualified_name[next_namespace_len] == ':');
2760 next_namespace_len += 2;
2761 }
2762 next_namespace_len +=
2763 cp_find_first_component (qualified_name + next_namespace_len);
2764
2765 /* Initialize these to values that can safely be xfree'd. */
2766 *oload_syms = NULL;
2767 *oload_champ_bv = NULL;
2768
2769 /* First, see if we have a deeper namespace we can search in.
2770 If we get a good match there, use it. */
2771
2772 if (qualified_name[next_namespace_len] == ':')
2773 {
2774 searched_deeper = 1;
2775
2776 if (find_oload_champ_namespace_loop (arg_types, nargs,
2777 func_name, qualified_name,
2778 next_namespace_len,
2779 oload_syms, oload_champ_bv,
2780 oload_champ, no_adl))
2781 {
2782 return 1;
2783 }
2784 };
2785
2786 /* If we reach here, either we're in the deepest namespace or we
2787 didn't find a good match in a deeper namespace. But, in the
2788 latter case, we still have a bad match in a deeper namespace;
2789 note that we might not find any match at all in the current
2790 namespace. (There's always a match in the deepest namespace,
2791 because this overload mechanism only gets called if there's a
2792 function symbol to start off with.) */
2793
2794 old_cleanups = make_cleanup (xfree, *oload_syms);
2795 make_cleanup (xfree, *oload_champ_bv);
2796 new_namespace = alloca (namespace_len + 1);
2797 strncpy (new_namespace, qualified_name, namespace_len);
2798 new_namespace[namespace_len] = '\0';
2799 new_oload_syms = make_symbol_overload_list (func_name,
2800 new_namespace);
2801
2802 /* If we have reached the deepest level perform argument
2803 determined lookup. */
2804 if (!searched_deeper && !no_adl)
2805 make_symbol_overload_list_adl (arg_types, nargs, func_name);
2806
2807 while (new_oload_syms[num_fns])
2808 ++num_fns;
2809
2810 new_oload_champ = find_oload_champ (arg_types, nargs, 0, num_fns,
2811 NULL, new_oload_syms,
2812 &new_oload_champ_bv);
2813
2814 /* Case 1: We found a good match. Free earlier matches (if any),
2815 and return it. Case 2: We didn't find a good match, but we're
2816 not the deepest function. Then go with the bad match that the
2817 deeper function found. Case 3: We found a bad match, and we're
2818 the deepest function. Then return what we found, even though
2819 it's a bad match. */
2820
2821 if (new_oload_champ != -1
2822 && classify_oload_match (new_oload_champ_bv, nargs, 0) == STANDARD)
2823 {
2824 *oload_syms = new_oload_syms;
2825 *oload_champ = new_oload_champ;
2826 *oload_champ_bv = new_oload_champ_bv;
2827 do_cleanups (old_cleanups);
2828 return 1;
2829 }
2830 else if (searched_deeper)
2831 {
2832 xfree (new_oload_syms);
2833 xfree (new_oload_champ_bv);
2834 discard_cleanups (old_cleanups);
2835 return 0;
2836 }
2837 else
2838 {
2839 *oload_syms = new_oload_syms;
2840 *oload_champ = new_oload_champ;
2841 *oload_champ_bv = new_oload_champ_bv;
2842 do_cleanups (old_cleanups);
2843 return 0;
2844 }
2845 }
2846
2847 /* Look for a function to take NARGS args of types ARG_TYPES. Find
2848 the best match from among the overloaded methods or functions
2849 (depending on METHOD) given by FNS_PTR or OLOAD_SYMS, respectively.
2850 The number of methods/functions in the list is given by NUM_FNS.
2851 Return the index of the best match; store an indication of the
2852 quality of the match in OLOAD_CHAMP_BV.
2853
2854 It is the caller's responsibility to free *OLOAD_CHAMP_BV. */
2855
2856 static int
2857 find_oload_champ (struct type **arg_types, int nargs, int method,
2858 int num_fns, struct fn_field *fns_ptr,
2859 struct symbol **oload_syms,
2860 struct badness_vector **oload_champ_bv)
2861 {
2862 int ix;
2863 /* A measure of how good an overloaded instance is. */
2864 struct badness_vector *bv;
2865 /* Index of best overloaded function. */
2866 int oload_champ = -1;
2867 /* Current ambiguity state for overload resolution. */
2868 int oload_ambiguous = 0;
2869 /* 0 => no ambiguity, 1 => two good funcs, 2 => incomparable funcs. */
2870
2871 *oload_champ_bv = NULL;
2872
2873 /* Consider each candidate in turn. */
2874 for (ix = 0; ix < num_fns; ix++)
2875 {
2876 int jj;
2877 int static_offset = oload_method_static (method, fns_ptr, ix);
2878 int nparms;
2879 struct type **parm_types;
2880
2881 if (method)
2882 {
2883 nparms = TYPE_NFIELDS (TYPE_FN_FIELD_TYPE (fns_ptr, ix));
2884 }
2885 else
2886 {
2887 /* If it's not a method, this is the proper place. */
2888 nparms = TYPE_NFIELDS (SYMBOL_TYPE (oload_syms[ix]));
2889 }
2890
2891 /* Prepare array of parameter types. */
2892 parm_types = (struct type **)
2893 xmalloc (nparms * (sizeof (struct type *)));
2894 for (jj = 0; jj < nparms; jj++)
2895 parm_types[jj] = (method
2896 ? (TYPE_FN_FIELD_ARGS (fns_ptr, ix)[jj].type)
2897 : TYPE_FIELD_TYPE (SYMBOL_TYPE (oload_syms[ix]),
2898 jj));
2899
2900 /* Compare parameter types to supplied argument types. Skip
2901 THIS for static methods. */
2902 bv = rank_function (parm_types, nparms,
2903 arg_types + static_offset,
2904 nargs - static_offset);
2905
2906 if (!*oload_champ_bv)
2907 {
2908 *oload_champ_bv = bv;
2909 oload_champ = 0;
2910 }
2911 else /* See whether current candidate is better or worse than
2912 previous best. */
2913 switch (compare_badness (bv, *oload_champ_bv))
2914 {
2915 case 0: /* Top two contenders are equally good. */
2916 oload_ambiguous = 1;
2917 break;
2918 case 1: /* Incomparable top contenders. */
2919 oload_ambiguous = 2;
2920 break;
2921 case 2: /* New champion, record details. */
2922 *oload_champ_bv = bv;
2923 oload_ambiguous = 0;
2924 oload_champ = ix;
2925 break;
2926 case 3:
2927 default:
2928 break;
2929 }
2930 xfree (parm_types);
2931 if (overload_debug)
2932 {
2933 if (method)
2934 fprintf_filtered (gdb_stderr,
2935 "Overloaded method instance %s, # of parms %d\n",
2936 fns_ptr[ix].physname, nparms);
2937 else
2938 fprintf_filtered (gdb_stderr,
2939 "Overloaded function instance "
2940 "%s # of parms %d\n",
2941 SYMBOL_DEMANGLED_NAME (oload_syms[ix]),
2942 nparms);
2943 for (jj = 0; jj < nargs - static_offset; jj++)
2944 fprintf_filtered (gdb_stderr,
2945 "...Badness @ %d : %d\n",
2946 jj, bv->rank[jj].rank);
2947 fprintf_filtered (gdb_stderr, "Overload resolution "
2948 "champion is %d, ambiguous? %d\n",
2949 oload_champ, oload_ambiguous);
2950 }
2951 }
2952
2953 return oload_champ;
2954 }
2955
2956 /* Return 1 if we're looking at a static method, 0 if we're looking at
2957 a non-static method or a function that isn't a method. */
2958
2959 static int
2960 oload_method_static (int method, struct fn_field *fns_ptr, int index)
2961 {
2962 if (method && fns_ptr && index >= 0
2963 && TYPE_FN_FIELD_STATIC_P (fns_ptr, index))
2964 return 1;
2965 else
2966 return 0;
2967 }
2968
2969 /* Check how good an overload match OLOAD_CHAMP_BV represents. */
2970
2971 static enum oload_classification
2972 classify_oload_match (struct badness_vector *oload_champ_bv,
2973 int nargs,
2974 int static_offset)
2975 {
2976 int ix;
2977
2978 for (ix = 1; ix <= nargs - static_offset; ix++)
2979 {
2980 /* If this conversion is as bad as INCOMPATIBLE_TYPE_BADNESS
2981 or worse return INCOMPATIBLE. */
2982 if (compare_ranks (oload_champ_bv->rank[ix],
2983 INCOMPATIBLE_TYPE_BADNESS) <= 0)
2984 return INCOMPATIBLE; /* Truly mismatched types. */
2985 /* Otherwise If this conversion is as bad as
2986 NS_POINTER_CONVERSION_BADNESS or worse return NON_STANDARD. */
2987 else if (compare_ranks (oload_champ_bv->rank[ix],
2988 NS_POINTER_CONVERSION_BADNESS) <= 0)
2989 return NON_STANDARD; /* Non-standard type conversions
2990 needed. */
2991 }
2992
2993 return STANDARD; /* Only standard conversions needed. */
2994 }
2995
2996 /* C++: return 1 is NAME is a legitimate name for the destructor of
2997 type TYPE. If TYPE does not have a destructor, or if NAME is
2998 inappropriate for TYPE, an error is signaled. */
2999 int
3000 destructor_name_p (const char *name, const struct type *type)
3001 {
3002 if (name[0] == '~')
3003 {
3004 char *dname = type_name_no_tag (type);
3005 char *cp = strchr (dname, '<');
3006 unsigned int len;
3007
3008 /* Do not compare the template part for template classes. */
3009 if (cp == NULL)
3010 len = strlen (dname);
3011 else
3012 len = cp - dname;
3013 if (strlen (name + 1) != len || strncmp (dname, name + 1, len) != 0)
3014 error (_("name of destructor must equal name of class"));
3015 else
3016 return 1;
3017 }
3018 return 0;
3019 }
3020
3021 /* Given TYPE, a structure/union,
3022 return 1 if the component named NAME from the ultimate target
3023 structure/union is defined, otherwise, return 0. */
3024
3025 int
3026 check_field (struct type *type, const char *name)
3027 {
3028 int i;
3029
3030 /* The type may be a stub. */
3031 CHECK_TYPEDEF (type);
3032
3033 for (i = TYPE_NFIELDS (type) - 1; i >= TYPE_N_BASECLASSES (type); i--)
3034 {
3035 char *t_field_name = TYPE_FIELD_NAME (type, i);
3036
3037 if (t_field_name && (strcmp_iw (t_field_name, name) == 0))
3038 return 1;
3039 }
3040
3041 /* C++: If it was not found as a data field, then try to return it
3042 as a pointer to a method. */
3043
3044 for (i = TYPE_NFN_FIELDS (type) - 1; i >= 0; --i)
3045 {
3046 if (strcmp_iw (TYPE_FN_FIELDLIST_NAME (type, i), name) == 0)
3047 return 1;
3048 }
3049
3050 for (i = TYPE_N_BASECLASSES (type) - 1; i >= 0; i--)
3051 if (check_field (TYPE_BASECLASS (type, i), name))
3052 return 1;
3053
3054 return 0;
3055 }
3056
3057 /* C++: Given an aggregate type CURTYPE, and a member name NAME,
3058 return the appropriate member (or the address of the member, if
3059 WANT_ADDRESS). This function is used to resolve user expressions
3060 of the form "DOMAIN::NAME". For more details on what happens, see
3061 the comment before value_struct_elt_for_reference. */
3062
3063 struct value *
3064 value_aggregate_elt (struct type *curtype, char *name,
3065 struct type *expect_type, int want_address,
3066 enum noside noside)
3067 {
3068 switch (TYPE_CODE (curtype))
3069 {
3070 case TYPE_CODE_STRUCT:
3071 case TYPE_CODE_UNION:
3072 return value_struct_elt_for_reference (curtype, 0, curtype,
3073 name, expect_type,
3074 want_address, noside);
3075 case TYPE_CODE_NAMESPACE:
3076 return value_namespace_elt (curtype, name,
3077 want_address, noside);
3078 default:
3079 internal_error (__FILE__, __LINE__,
3080 _("non-aggregate type in value_aggregate_elt"));
3081 }
3082 }
3083
3084 /* Compares the two method/function types T1 and T2 for "equality"
3085 with respect to the the methods' parameters. If the types of the
3086 two parameter lists are the same, returns 1; 0 otherwise. This
3087 comparison may ignore any artificial parameters in T1 if
3088 SKIP_ARTIFICIAL is non-zero. This function will ALWAYS skip
3089 the first artificial parameter in T1, assumed to be a 'this' pointer.
3090
3091 The type T2 is expected to have come from make_params (in eval.c). */
3092
3093 static int
3094 compare_parameters (struct type *t1, struct type *t2, int skip_artificial)
3095 {
3096 int start = 0;
3097
3098 if (TYPE_FIELD_ARTIFICIAL (t1, 0))
3099 ++start;
3100
3101 /* If skipping artificial fields, find the first real field
3102 in T1. */
3103 if (skip_artificial)
3104 {
3105 while (start < TYPE_NFIELDS (t1)
3106 && TYPE_FIELD_ARTIFICIAL (t1, start))
3107 ++start;
3108 }
3109
3110 /* Now compare parameters. */
3111
3112 /* Special case: a method taking void. T1 will contain no
3113 non-artificial fields, and T2 will contain TYPE_CODE_VOID. */
3114 if ((TYPE_NFIELDS (t1) - start) == 0 && TYPE_NFIELDS (t2) == 1
3115 && TYPE_CODE (TYPE_FIELD_TYPE (t2, 0)) == TYPE_CODE_VOID)
3116 return 1;
3117
3118 if ((TYPE_NFIELDS (t1) - start) == TYPE_NFIELDS (t2))
3119 {
3120 int i;
3121
3122 for (i = 0; i < TYPE_NFIELDS (t2); ++i)
3123 {
3124 if (compare_ranks (rank_one_type (TYPE_FIELD_TYPE (t1, start + i),
3125 TYPE_FIELD_TYPE (t2, i)),
3126 EXACT_MATCH_BADNESS) != 0)
3127 return 0;
3128 }
3129
3130 return 1;
3131 }
3132
3133 return 0;
3134 }
3135
3136 /* C++: Given an aggregate type CURTYPE, and a member name NAME,
3137 return the address of this member as a "pointer to member" type.
3138 If INTYPE is non-null, then it will be the type of the member we
3139 are looking for. This will help us resolve "pointers to member
3140 functions". This function is used to resolve user expressions of
3141 the form "DOMAIN::NAME". */
3142
3143 static struct value *
3144 value_struct_elt_for_reference (struct type *domain, int offset,
3145 struct type *curtype, char *name,
3146 struct type *intype,
3147 int want_address,
3148 enum noside noside)
3149 {
3150 struct type *t = curtype;
3151 int i;
3152 struct value *v, *result;
3153
3154 if (TYPE_CODE (t) != TYPE_CODE_STRUCT
3155 && TYPE_CODE (t) != TYPE_CODE_UNION)
3156 error (_("Internal error: non-aggregate type "
3157 "to value_struct_elt_for_reference"));
3158
3159 for (i = TYPE_NFIELDS (t) - 1; i >= TYPE_N_BASECLASSES (t); i--)
3160 {
3161 char *t_field_name = TYPE_FIELD_NAME (t, i);
3162
3163 if (t_field_name && strcmp (t_field_name, name) == 0)
3164 {
3165 if (field_is_static (&TYPE_FIELD (t, i)))
3166 {
3167 v = value_static_field (t, i);
3168 if (v == NULL)
3169 error (_("static field %s has been optimized out"),
3170 name);
3171 if (want_address)
3172 v = value_addr (v);
3173 return v;
3174 }
3175 if (TYPE_FIELD_PACKED (t, i))
3176 error (_("pointers to bitfield members not allowed"));
3177
3178 if (want_address)
3179 return value_from_longest
3180 (lookup_memberptr_type (TYPE_FIELD_TYPE (t, i), domain),
3181 offset + (LONGEST) (TYPE_FIELD_BITPOS (t, i) >> 3));
3182 else if (noside == EVAL_AVOID_SIDE_EFFECTS)
3183 return allocate_value (TYPE_FIELD_TYPE (t, i));
3184 else
3185 error (_("Cannot reference non-static field \"%s\""), name);
3186 }
3187 }
3188
3189 /* C++: If it was not found as a data field, then try to return it
3190 as a pointer to a method. */
3191
3192 /* Perform all necessary dereferencing. */
3193 while (intype && TYPE_CODE (intype) == TYPE_CODE_PTR)
3194 intype = TYPE_TARGET_TYPE (intype);
3195
3196 for (i = TYPE_NFN_FIELDS (t) - 1; i >= 0; --i)
3197 {
3198 char *t_field_name = TYPE_FN_FIELDLIST_NAME (t, i);
3199 char dem_opname[64];
3200
3201 if (strncmp (t_field_name, "__", 2) == 0
3202 || strncmp (t_field_name, "op", 2) == 0
3203 || strncmp (t_field_name, "type", 4) == 0)
3204 {
3205 if (cplus_demangle_opname (t_field_name,
3206 dem_opname, DMGL_ANSI))
3207 t_field_name = dem_opname;
3208 else if (cplus_demangle_opname (t_field_name,
3209 dem_opname, 0))
3210 t_field_name = dem_opname;
3211 }
3212 if (t_field_name && strcmp (t_field_name, name) == 0)
3213 {
3214 int j;
3215 int len = TYPE_FN_FIELDLIST_LENGTH (t, i);
3216 struct fn_field *f = TYPE_FN_FIELDLIST1 (t, i);
3217
3218 check_stub_method_group (t, i);
3219
3220 if (intype)
3221 {
3222 for (j = 0; j < len; ++j)
3223 {
3224 if (compare_parameters (TYPE_FN_FIELD_TYPE (f, j), intype, 0)
3225 || compare_parameters (TYPE_FN_FIELD_TYPE (f, j),
3226 intype, 1))
3227 break;
3228 }
3229
3230 if (j == len)
3231 error (_("no member function matches "
3232 "that type instantiation"));
3233 }
3234 else
3235 {
3236 int ii;
3237
3238 j = -1;
3239 for (ii = 0; ii < TYPE_FN_FIELDLIST_LENGTH (t, i);
3240 ++ii)
3241 {
3242 /* Skip artificial methods. This is necessary if,
3243 for example, the user wants to "print
3244 subclass::subclass" with only one user-defined
3245 constructor. There is no ambiguity in this
3246 case. */
3247 if (TYPE_FN_FIELD_ARTIFICIAL (f, ii))
3248 continue;
3249
3250 /* Desired method is ambiguous if more than one
3251 method is defined. */
3252 if (j != -1)
3253 error (_("non-unique member `%s' requires "
3254 "type instantiation"), name);
3255
3256 j = ii;
3257 }
3258 }
3259
3260 if (TYPE_FN_FIELD_STATIC_P (f, j))
3261 {
3262 struct symbol *s =
3263 lookup_symbol (TYPE_FN_FIELD_PHYSNAME (f, j),
3264 0, VAR_DOMAIN, 0);
3265
3266 if (s == NULL)
3267 return NULL;
3268
3269 if (want_address)
3270 return value_addr (read_var_value (s, 0));
3271 else
3272 return read_var_value (s, 0);
3273 }
3274
3275 if (TYPE_FN_FIELD_VIRTUAL_P (f, j))
3276 {
3277 if (want_address)
3278 {
3279 result = allocate_value
3280 (lookup_methodptr_type (TYPE_FN_FIELD_TYPE (f, j)));
3281 cplus_make_method_ptr (value_type (result),
3282 value_contents_writeable (result),
3283 TYPE_FN_FIELD_VOFFSET (f, j), 1);
3284 }
3285 else if (noside == EVAL_AVOID_SIDE_EFFECTS)
3286 return allocate_value (TYPE_FN_FIELD_TYPE (f, j));
3287 else
3288 error (_("Cannot reference virtual member function \"%s\""),
3289 name);
3290 }
3291 else
3292 {
3293 struct symbol *s =
3294 lookup_symbol (TYPE_FN_FIELD_PHYSNAME (f, j),
3295 0, VAR_DOMAIN, 0);
3296
3297 if (s == NULL)
3298 return NULL;
3299
3300 v = read_var_value (s, 0);
3301 if (!want_address)
3302 result = v;
3303 else
3304 {
3305 result = allocate_value (lookup_methodptr_type (TYPE_FN_FIELD_TYPE (f, j)));
3306 cplus_make_method_ptr (value_type (result),
3307 value_contents_writeable (result),
3308 value_address (v), 0);
3309 }
3310 }
3311 return result;
3312 }
3313 }
3314 for (i = TYPE_N_BASECLASSES (t) - 1; i >= 0; i--)
3315 {
3316 struct value *v;
3317 int base_offset;
3318
3319 if (BASETYPE_VIA_VIRTUAL (t, i))
3320 base_offset = 0;
3321 else
3322 base_offset = TYPE_BASECLASS_BITPOS (t, i) / 8;
3323 v = value_struct_elt_for_reference (domain,
3324 offset + base_offset,
3325 TYPE_BASECLASS (t, i),
3326 name, intype,
3327 want_address, noside);
3328 if (v)
3329 return v;
3330 }
3331
3332 /* As a last chance, pretend that CURTYPE is a namespace, and look
3333 it up that way; this (frequently) works for types nested inside
3334 classes. */
3335
3336 return value_maybe_namespace_elt (curtype, name,
3337 want_address, noside);
3338 }
3339
3340 /* C++: Return the member NAME of the namespace given by the type
3341 CURTYPE. */
3342
3343 static struct value *
3344 value_namespace_elt (const struct type *curtype,
3345 char *name, int want_address,
3346 enum noside noside)
3347 {
3348 struct value *retval = value_maybe_namespace_elt (curtype, name,
3349 want_address,
3350 noside);
3351
3352 if (retval == NULL)
3353 error (_("No symbol \"%s\" in namespace \"%s\"."),
3354 name, TYPE_TAG_NAME (curtype));
3355
3356 return retval;
3357 }
3358
3359 /* A helper function used by value_namespace_elt and
3360 value_struct_elt_for_reference. It looks up NAME inside the
3361 context CURTYPE; this works if CURTYPE is a namespace or if CURTYPE
3362 is a class and NAME refers to a type in CURTYPE itself (as opposed
3363 to, say, some base class of CURTYPE). */
3364
3365 static struct value *
3366 value_maybe_namespace_elt (const struct type *curtype,
3367 char *name, int want_address,
3368 enum noside noside)
3369 {
3370 const char *namespace_name = TYPE_TAG_NAME (curtype);
3371 struct symbol *sym;
3372 struct value *result;
3373
3374 sym = cp_lookup_symbol_namespace (namespace_name, name,
3375 get_selected_block (0), VAR_DOMAIN);
3376
3377 if (sym == NULL)
3378 {
3379 char *concatenated_name = alloca (strlen (namespace_name) + 2
3380 + strlen (name) + 1);
3381
3382 sprintf (concatenated_name, "%s::%s", namespace_name, name);
3383 sym = lookup_static_symbol_aux (concatenated_name, VAR_DOMAIN);
3384 }
3385
3386 if (sym == NULL)
3387 return NULL;
3388 else if ((noside == EVAL_AVOID_SIDE_EFFECTS)
3389 && (SYMBOL_CLASS (sym) == LOC_TYPEDEF))
3390 result = allocate_value (SYMBOL_TYPE (sym));
3391 else
3392 result = value_of_variable (sym, get_selected_block (0));
3393
3394 if (result && want_address)
3395 result = value_addr (result);
3396
3397 return result;
3398 }
3399
3400 /* Given a pointer value V, find the real (RTTI) type of the object it
3401 points to.
3402
3403 Other parameters FULL, TOP, USING_ENC as with value_rtti_type()
3404 and refer to the values computed for the object pointed to. */
3405
3406 struct type *
3407 value_rtti_target_type (struct value *v, int *full,
3408 int *top, int *using_enc)
3409 {
3410 struct value *target;
3411
3412 target = value_ind (v);
3413
3414 return value_rtti_type (target, full, top, using_enc);
3415 }
3416
3417 /* Given a value pointed to by ARGP, check its real run-time type, and
3418 if that is different from the enclosing type, create a new value
3419 using the real run-time type as the enclosing type (and of the same
3420 type as ARGP) and return it, with the embedded offset adjusted to
3421 be the correct offset to the enclosed object. RTYPE is the type,
3422 and XFULL, XTOP, and XUSING_ENC are the other parameters, computed
3423 by value_rtti_type(). If these are available, they can be supplied
3424 and a second call to value_rtti_type() is avoided. (Pass RTYPE ==
3425 NULL if they're not available. */
3426
3427 struct value *
3428 value_full_object (struct value *argp,
3429 struct type *rtype,
3430 int xfull, int xtop,
3431 int xusing_enc)
3432 {
3433 struct type *real_type;
3434 int full = 0;
3435 int top = -1;
3436 int using_enc = 0;
3437 struct value *new_val;
3438
3439 if (rtype)
3440 {
3441 real_type = rtype;
3442 full = xfull;
3443 top = xtop;
3444 using_enc = xusing_enc;
3445 }
3446 else
3447 real_type = value_rtti_type (argp, &full, &top, &using_enc);
3448
3449 /* If no RTTI data, or if object is already complete, do nothing. */
3450 if (!real_type || real_type == value_enclosing_type (argp))
3451 return argp;
3452
3453 /* If we have the full object, but for some reason the enclosing
3454 type is wrong, set it. */
3455 /* pai: FIXME -- sounds iffy */
3456 if (full)
3457 {
3458 argp = value_copy (argp);
3459 set_value_enclosing_type (argp, real_type);
3460 return argp;
3461 }
3462
3463 /* Check if object is in memory. */
3464 if (VALUE_LVAL (argp) != lval_memory)
3465 {
3466 warning (_("Couldn't retrieve complete object of RTTI "
3467 "type %s; object may be in register(s)."),
3468 TYPE_NAME (real_type));
3469
3470 return argp;
3471 }
3472
3473 /* All other cases -- retrieve the complete object. */
3474 /* Go back by the computed top_offset from the beginning of the
3475 object, adjusting for the embedded offset of argp if that's what
3476 value_rtti_type used for its computation. */
3477 new_val = value_at_lazy (real_type, value_address (argp) - top +
3478 (using_enc ? 0 : value_embedded_offset (argp)));
3479 deprecated_set_value_type (new_val, value_type (argp));
3480 set_value_embedded_offset (new_val, (using_enc
3481 ? top + value_embedded_offset (argp)
3482 : top));
3483 return new_val;
3484 }
3485
3486
3487 /* Return the value of the local variable, if one exists.
3488 Flag COMPLAIN signals an error if the request is made in an
3489 inappropriate context. */
3490
3491 struct value *
3492 value_of_local (const char *name, int complain)
3493 {
3494 struct symbol *func, *sym;
3495 struct block *b;
3496 struct value * ret;
3497 struct frame_info *frame;
3498
3499 if (complain)
3500 frame = get_selected_frame (_("no frame selected"));
3501 else
3502 {
3503 frame = deprecated_safe_get_selected_frame ();
3504 if (frame == 0)
3505 return 0;
3506 }
3507
3508 func = get_frame_function (frame);
3509 if (!func)
3510 {
3511 if (complain)
3512 error (_("no `%s' in nameless context"), name);
3513 else
3514 return 0;
3515 }
3516
3517 b = SYMBOL_BLOCK_VALUE (func);
3518 if (dict_empty (BLOCK_DICT (b)))
3519 {
3520 if (complain)
3521 error (_("no args, no `%s'"), name);
3522 else
3523 return 0;
3524 }
3525
3526 /* Calling lookup_block_symbol is necessary to get the LOC_REGISTER
3527 symbol instead of the LOC_ARG one (if both exist). */
3528 sym = lookup_block_symbol (b, name, VAR_DOMAIN);
3529 if (sym == NULL)
3530 {
3531 if (complain)
3532 error (_("current stack frame does not contain a variable named `%s'"),
3533 name);
3534 else
3535 return NULL;
3536 }
3537
3538 ret = read_var_value (sym, frame);
3539 if (ret == 0 && complain)
3540 error (_("`%s' argument unreadable"), name);
3541 return ret;
3542 }
3543
3544 /* C++/Objective-C: return the value of the class instance variable,
3545 if one exists. Flag COMPLAIN signals an error if the request is
3546 made in an inappropriate context. */
3547
3548 struct value *
3549 value_of_this (int complain)
3550 {
3551 if (!current_language->la_name_of_this)
3552 return 0;
3553 return value_of_local (current_language->la_name_of_this, complain);
3554 }
3555
3556 /* Create a slice (sub-string, sub-array) of ARRAY, that is LENGTH
3557 elements long, starting at LOWBOUND. The result has the same lower
3558 bound as the original ARRAY. */
3559
3560 struct value *
3561 value_slice (struct value *array, int lowbound, int length)
3562 {
3563 struct type *slice_range_type, *slice_type, *range_type;
3564 LONGEST lowerbound, upperbound;
3565 struct value *slice;
3566 struct type *array_type;
3567
3568 array_type = check_typedef (value_type (array));
3569 if (TYPE_CODE (array_type) != TYPE_CODE_ARRAY
3570 && TYPE_CODE (array_type) != TYPE_CODE_STRING
3571 && TYPE_CODE (array_type) != TYPE_CODE_BITSTRING)
3572 error (_("cannot take slice of non-array"));
3573
3574 range_type = TYPE_INDEX_TYPE (array_type);
3575 if (get_discrete_bounds (range_type, &lowerbound, &upperbound) < 0)
3576 error (_("slice from bad array or bitstring"));
3577
3578 if (lowbound < lowerbound || length < 0
3579 || lowbound + length - 1 > upperbound)
3580 error (_("slice out of range"));
3581
3582 /* FIXME-type-allocation: need a way to free this type when we are
3583 done with it. */
3584 slice_range_type = create_range_type ((struct type *) NULL,
3585 TYPE_TARGET_TYPE (range_type),
3586 lowbound,
3587 lowbound + length - 1);
3588 if (TYPE_CODE (array_type) == TYPE_CODE_BITSTRING)
3589 {
3590 int i;
3591
3592 slice_type = create_set_type ((struct type *) NULL,
3593 slice_range_type);
3594 TYPE_CODE (slice_type) = TYPE_CODE_BITSTRING;
3595 slice = value_zero (slice_type, not_lval);
3596
3597 for (i = 0; i < length; i++)
3598 {
3599 int element = value_bit_index (array_type,
3600 value_contents (array),
3601 lowbound + i);
3602
3603 if (element < 0)
3604 error (_("internal error accessing bitstring"));
3605 else if (element > 0)
3606 {
3607 int j = i % TARGET_CHAR_BIT;
3608
3609 if (gdbarch_bits_big_endian (get_type_arch (array_type)))
3610 j = TARGET_CHAR_BIT - 1 - j;
3611 value_contents_raw (slice)[i / TARGET_CHAR_BIT] |= (1 << j);
3612 }
3613 }
3614 /* We should set the address, bitssize, and bitspos, so the
3615 slice can be used on the LHS, but that may require extensions
3616 to value_assign. For now, just leave as a non_lval.
3617 FIXME. */
3618 }
3619 else
3620 {
3621 struct type *element_type = TYPE_TARGET_TYPE (array_type);
3622 LONGEST offset =
3623 (lowbound - lowerbound) * TYPE_LENGTH (check_typedef (element_type));
3624
3625 slice_type = create_array_type ((struct type *) NULL,
3626 element_type,
3627 slice_range_type);
3628 TYPE_CODE (slice_type) = TYPE_CODE (array_type);
3629
3630 if (VALUE_LVAL (array) == lval_memory && value_lazy (array))
3631 slice = allocate_value_lazy (slice_type);
3632 else
3633 {
3634 slice = allocate_value (slice_type);
3635 memcpy (value_contents_writeable (slice),
3636 value_contents (array) + offset,
3637 TYPE_LENGTH (slice_type));
3638 }
3639
3640 set_value_component_location (slice, array);
3641 VALUE_FRAME_ID (slice) = VALUE_FRAME_ID (array);
3642 set_value_offset (slice, value_offset (array) + offset);
3643 }
3644 return slice;
3645 }
3646
3647 /* Create a value for a FORTRAN complex number. Currently most of the
3648 time values are coerced to COMPLEX*16 (i.e. a complex number
3649 composed of 2 doubles. This really should be a smarter routine
3650 that figures out precision inteligently as opposed to assuming
3651 doubles. FIXME: fmb */
3652
3653 struct value *
3654 value_literal_complex (struct value *arg1,
3655 struct value *arg2,
3656 struct type *type)
3657 {
3658 struct value *val;
3659 struct type *real_type = TYPE_TARGET_TYPE (type);
3660
3661 val = allocate_value (type);
3662 arg1 = value_cast (real_type, arg1);
3663 arg2 = value_cast (real_type, arg2);
3664
3665 memcpy (value_contents_raw (val),
3666 value_contents (arg1), TYPE_LENGTH (real_type));
3667 memcpy (value_contents_raw (val) + TYPE_LENGTH (real_type),
3668 value_contents (arg2), TYPE_LENGTH (real_type));
3669 return val;
3670 }
3671
3672 /* Cast a value into the appropriate complex data type. */
3673
3674 static struct value *
3675 cast_into_complex (struct type *type, struct value *val)
3676 {
3677 struct type *real_type = TYPE_TARGET_TYPE (type);
3678
3679 if (TYPE_CODE (value_type (val)) == TYPE_CODE_COMPLEX)
3680 {
3681 struct type *val_real_type = TYPE_TARGET_TYPE (value_type (val));
3682 struct value *re_val = allocate_value (val_real_type);
3683 struct value *im_val = allocate_value (val_real_type);
3684
3685 memcpy (value_contents_raw (re_val),
3686 value_contents (val), TYPE_LENGTH (val_real_type));
3687 memcpy (value_contents_raw (im_val),
3688 value_contents (val) + TYPE_LENGTH (val_real_type),
3689 TYPE_LENGTH (val_real_type));
3690
3691 return value_literal_complex (re_val, im_val, type);
3692 }
3693 else if (TYPE_CODE (value_type (val)) == TYPE_CODE_FLT
3694 || TYPE_CODE (value_type (val)) == TYPE_CODE_INT)
3695 return value_literal_complex (val,
3696 value_zero (real_type, not_lval),
3697 type);
3698 else
3699 error (_("cannot cast non-number to complex"));
3700 }
3701
3702 void
3703 _initialize_valops (void)
3704 {
3705 add_setshow_boolean_cmd ("overload-resolution", class_support,
3706 &overload_resolution, _("\
3707 Set overload resolution in evaluating C++ functions."), _("\
3708 Show overload resolution in evaluating C++ functions."),
3709 NULL, NULL,
3710 show_overload_resolution,
3711 &setlist, &showlist);
3712 overload_resolution = 1;
3713 }