search_struct_field: remove OFFSET parameter
[deliverable/binutils-gdb.git] / gdb / valops.c
1 /* Perform non-arithmetic operations on values, for GDB.
2
3 Copyright (C) 1986-2015 Free Software Foundation, Inc.
4
5 This file is part of GDB.
6
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 3 of the License, or
10 (at your option) any later version.
11
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
16
17 You should have received a copy of the GNU General Public License
18 along with this program. If not, see <http://www.gnu.org/licenses/>. */
19
20 #include "defs.h"
21 #include "symtab.h"
22 #include "gdbtypes.h"
23 #include "value.h"
24 #include "frame.h"
25 #include "inferior.h"
26 #include "gdbcore.h"
27 #include "target.h"
28 #include "demangle.h"
29 #include "language.h"
30 #include "gdbcmd.h"
31 #include "regcache.h"
32 #include "cp-abi.h"
33 #include "block.h"
34 #include "infcall.h"
35 #include "dictionary.h"
36 #include "cp-support.h"
37 #include "dfp.h"
38 #include "tracepoint.h"
39 #include "observer.h"
40 #include "objfiles.h"
41 #include "extension.h"
42
43 extern unsigned int overload_debug;
44 /* Local functions. */
45
46 static int typecmp (int staticp, int varargs, int nargs,
47 struct field t1[], struct value *t2[]);
48
49 static struct value *search_struct_field (const char *, struct value *,
50 struct type *, int);
51
52 static struct value *search_struct_method (const char *, struct value **,
53 struct value **,
54 int, int *, struct type *);
55
56 static int find_oload_champ_namespace (struct value **, int,
57 const char *, const char *,
58 struct symbol ***,
59 struct badness_vector **,
60 const int no_adl);
61
62 static
63 int find_oload_champ_namespace_loop (struct value **, int,
64 const char *, const char *,
65 int, struct symbol ***,
66 struct badness_vector **, int *,
67 const int no_adl);
68
69 static int find_oload_champ (struct value **, int, int,
70 struct fn_field *, VEC (xmethod_worker_ptr) *,
71 struct symbol **, struct badness_vector **);
72
73 static int oload_method_static_p (struct fn_field *, int);
74
75 enum oload_classification { STANDARD, NON_STANDARD, INCOMPATIBLE };
76
77 static enum
78 oload_classification classify_oload_match (struct badness_vector *,
79 int, int);
80
81 static struct value *value_struct_elt_for_reference (struct type *,
82 int, struct type *,
83 const char *,
84 struct type *,
85 int, enum noside);
86
87 static struct value *value_namespace_elt (const struct type *,
88 const char *, int , enum noside);
89
90 static struct value *value_maybe_namespace_elt (const struct type *,
91 const char *, int,
92 enum noside);
93
94 static CORE_ADDR allocate_space_in_inferior (int);
95
96 static struct value *cast_into_complex (struct type *, struct value *);
97
98 static void find_method_list (struct value **, const char *,
99 int, struct type *, struct fn_field **, int *,
100 VEC (xmethod_worker_ptr) **,
101 struct type **, int *);
102
103 void _initialize_valops (void);
104
105 #if 0
106 /* Flag for whether we want to abandon failed expression evals by
107 default. */
108
109 static int auto_abandon = 0;
110 #endif
111
112 int overload_resolution = 0;
113 static void
114 show_overload_resolution (struct ui_file *file, int from_tty,
115 struct cmd_list_element *c,
116 const char *value)
117 {
118 fprintf_filtered (file, _("Overload resolution in evaluating "
119 "C++ functions is %s.\n"),
120 value);
121 }
122
123 /* Find the address of function name NAME in the inferior. If OBJF_P
124 is non-NULL, *OBJF_P will be set to the OBJFILE where the function
125 is defined. */
126
127 struct value *
128 find_function_in_inferior (const char *name, struct objfile **objf_p)
129 {
130 struct symbol *sym;
131
132 sym = lookup_symbol (name, 0, VAR_DOMAIN, 0);
133 if (sym != NULL)
134 {
135 if (SYMBOL_CLASS (sym) != LOC_BLOCK)
136 {
137 error (_("\"%s\" exists in this program but is not a function."),
138 name);
139 }
140
141 if (objf_p)
142 *objf_p = symbol_objfile (sym);
143
144 return value_of_variable (sym, NULL);
145 }
146 else
147 {
148 struct bound_minimal_symbol msymbol =
149 lookup_bound_minimal_symbol (name);
150
151 if (msymbol.minsym != NULL)
152 {
153 struct objfile *objfile = msymbol.objfile;
154 struct gdbarch *gdbarch = get_objfile_arch (objfile);
155
156 struct type *type;
157 CORE_ADDR maddr;
158 type = lookup_pointer_type (builtin_type (gdbarch)->builtin_char);
159 type = lookup_function_type (type);
160 type = lookup_pointer_type (type);
161 maddr = BMSYMBOL_VALUE_ADDRESS (msymbol);
162
163 if (objf_p)
164 *objf_p = objfile;
165
166 return value_from_pointer (type, maddr);
167 }
168 else
169 {
170 if (!target_has_execution)
171 error (_("evaluation of this expression "
172 "requires the target program to be active"));
173 else
174 error (_("evaluation of this expression requires the "
175 "program to have a function \"%s\"."),
176 name);
177 }
178 }
179 }
180
181 /* Allocate NBYTES of space in the inferior using the inferior's
182 malloc and return a value that is a pointer to the allocated
183 space. */
184
185 struct value *
186 value_allocate_space_in_inferior (int len)
187 {
188 struct objfile *objf;
189 struct value *val = find_function_in_inferior ("malloc", &objf);
190 struct gdbarch *gdbarch = get_objfile_arch (objf);
191 struct value *blocklen;
192
193 blocklen = value_from_longest (builtin_type (gdbarch)->builtin_int, len);
194 val = call_function_by_hand (val, 1, &blocklen);
195 if (value_logical_not (val))
196 {
197 if (!target_has_execution)
198 error (_("No memory available to program now: "
199 "you need to start the target first"));
200 else
201 error (_("No memory available to program: call to malloc failed"));
202 }
203 return val;
204 }
205
206 static CORE_ADDR
207 allocate_space_in_inferior (int len)
208 {
209 return value_as_long (value_allocate_space_in_inferior (len));
210 }
211
212 /* Cast struct value VAL to type TYPE and return as a value.
213 Both type and val must be of TYPE_CODE_STRUCT or TYPE_CODE_UNION
214 for this to work. Typedef to one of the codes is permitted.
215 Returns NULL if the cast is neither an upcast nor a downcast. */
216
217 static struct value *
218 value_cast_structs (struct type *type, struct value *v2)
219 {
220 struct type *t1;
221 struct type *t2;
222 struct value *v;
223
224 gdb_assert (type != NULL && v2 != NULL);
225
226 t1 = check_typedef (type);
227 t2 = check_typedef (value_type (v2));
228
229 /* Check preconditions. */
230 gdb_assert ((TYPE_CODE (t1) == TYPE_CODE_STRUCT
231 || TYPE_CODE (t1) == TYPE_CODE_UNION)
232 && !!"Precondition is that type is of STRUCT or UNION kind.");
233 gdb_assert ((TYPE_CODE (t2) == TYPE_CODE_STRUCT
234 || TYPE_CODE (t2) == TYPE_CODE_UNION)
235 && !!"Precondition is that value is of STRUCT or UNION kind");
236
237 if (TYPE_NAME (t1) != NULL
238 && TYPE_NAME (t2) != NULL
239 && !strcmp (TYPE_NAME (t1), TYPE_NAME (t2)))
240 return NULL;
241
242 /* Upcasting: look in the type of the source to see if it contains the
243 type of the target as a superclass. If so, we'll need to
244 offset the pointer rather than just change its type. */
245 if (TYPE_NAME (t1) != NULL)
246 {
247 v = search_struct_field (type_name_no_tag (t1),
248 v2, t2, 1);
249 if (v)
250 return v;
251 }
252
253 /* Downcasting: look in the type of the target to see if it contains the
254 type of the source as a superclass. If so, we'll need to
255 offset the pointer rather than just change its type. */
256 if (TYPE_NAME (t2) != NULL)
257 {
258 /* Try downcasting using the run-time type of the value. */
259 int full, top, using_enc;
260 struct type *real_type;
261
262 real_type = value_rtti_type (v2, &full, &top, &using_enc);
263 if (real_type)
264 {
265 v = value_full_object (v2, real_type, full, top, using_enc);
266 v = value_at_lazy (real_type, value_address (v));
267 real_type = value_type (v);
268
269 /* We might be trying to cast to the outermost enclosing
270 type, in which case search_struct_field won't work. */
271 if (TYPE_NAME (real_type) != NULL
272 && !strcmp (TYPE_NAME (real_type), TYPE_NAME (t1)))
273 return v;
274
275 v = search_struct_field (type_name_no_tag (t2), v, real_type, 1);
276 if (v)
277 return v;
278 }
279
280 /* Try downcasting using information from the destination type
281 T2. This wouldn't work properly for classes with virtual
282 bases, but those were handled above. */
283 v = search_struct_field (type_name_no_tag (t2),
284 value_zero (t1, not_lval), t1, 1);
285 if (v)
286 {
287 /* Downcasting is possible (t1 is superclass of v2). */
288 CORE_ADDR addr2 = value_address (v2);
289
290 addr2 -= value_address (v) + value_embedded_offset (v);
291 return value_at (type, addr2);
292 }
293 }
294
295 return NULL;
296 }
297
298 /* Cast one pointer or reference type to another. Both TYPE and
299 the type of ARG2 should be pointer types, or else both should be
300 reference types. If SUBCLASS_CHECK is non-zero, this will force a
301 check to see whether TYPE is a superclass of ARG2's type. If
302 SUBCLASS_CHECK is zero, then the subclass check is done only when
303 ARG2 is itself non-zero. Returns the new pointer or reference. */
304
305 struct value *
306 value_cast_pointers (struct type *type, struct value *arg2,
307 int subclass_check)
308 {
309 struct type *type1 = check_typedef (type);
310 struct type *type2 = check_typedef (value_type (arg2));
311 struct type *t1 = check_typedef (TYPE_TARGET_TYPE (type1));
312 struct type *t2 = check_typedef (TYPE_TARGET_TYPE (type2));
313
314 if (TYPE_CODE (t1) == TYPE_CODE_STRUCT
315 && TYPE_CODE (t2) == TYPE_CODE_STRUCT
316 && (subclass_check || !value_logical_not (arg2)))
317 {
318 struct value *v2;
319
320 if (TYPE_CODE (type2) == TYPE_CODE_REF)
321 v2 = coerce_ref (arg2);
322 else
323 v2 = value_ind (arg2);
324 gdb_assert (TYPE_CODE (check_typedef (value_type (v2)))
325 == TYPE_CODE_STRUCT && !!"Why did coercion fail?");
326 v2 = value_cast_structs (t1, v2);
327 /* At this point we have what we can have, un-dereference if needed. */
328 if (v2)
329 {
330 struct value *v = value_addr (v2);
331
332 deprecated_set_value_type (v, type);
333 return v;
334 }
335 }
336
337 /* No superclass found, just change the pointer type. */
338 arg2 = value_copy (arg2);
339 deprecated_set_value_type (arg2, type);
340 set_value_enclosing_type (arg2, type);
341 set_value_pointed_to_offset (arg2, 0); /* pai: chk_val */
342 return arg2;
343 }
344
345 /* Cast value ARG2 to type TYPE and return as a value.
346 More general than a C cast: accepts any two types of the same length,
347 and if ARG2 is an lvalue it can be cast into anything at all. */
348 /* In C++, casts may change pointer or object representations. */
349
350 struct value *
351 value_cast (struct type *type, struct value *arg2)
352 {
353 enum type_code code1;
354 enum type_code code2;
355 int scalar;
356 struct type *type2;
357
358 int convert_to_boolean = 0;
359
360 if (value_type (arg2) == type)
361 return arg2;
362
363 code1 = TYPE_CODE (check_typedef (type));
364
365 /* Check if we are casting struct reference to struct reference. */
366 if (code1 == TYPE_CODE_REF)
367 {
368 /* We dereference type; then we recurse and finally
369 we generate value of the given reference. Nothing wrong with
370 that. */
371 struct type *t1 = check_typedef (type);
372 struct type *dereftype = check_typedef (TYPE_TARGET_TYPE (t1));
373 struct value *val = value_cast (dereftype, arg2);
374
375 return value_ref (val);
376 }
377
378 code2 = TYPE_CODE (check_typedef (value_type (arg2)));
379
380 if (code2 == TYPE_CODE_REF)
381 /* We deref the value and then do the cast. */
382 return value_cast (type, coerce_ref (arg2));
383
384 CHECK_TYPEDEF (type);
385 code1 = TYPE_CODE (type);
386 arg2 = coerce_ref (arg2);
387 type2 = check_typedef (value_type (arg2));
388
389 /* You can't cast to a reference type. See value_cast_pointers
390 instead. */
391 gdb_assert (code1 != TYPE_CODE_REF);
392
393 /* A cast to an undetermined-length array_type, such as
394 (TYPE [])OBJECT, is treated like a cast to (TYPE [N])OBJECT,
395 where N is sizeof(OBJECT)/sizeof(TYPE). */
396 if (code1 == TYPE_CODE_ARRAY)
397 {
398 struct type *element_type = TYPE_TARGET_TYPE (type);
399 unsigned element_length = TYPE_LENGTH (check_typedef (element_type));
400
401 if (element_length > 0 && TYPE_ARRAY_UPPER_BOUND_IS_UNDEFINED (type))
402 {
403 struct type *range_type = TYPE_INDEX_TYPE (type);
404 int val_length = TYPE_LENGTH (type2);
405 LONGEST low_bound, high_bound, new_length;
406
407 if (get_discrete_bounds (range_type, &low_bound, &high_bound) < 0)
408 low_bound = 0, high_bound = 0;
409 new_length = val_length / element_length;
410 if (val_length % element_length != 0)
411 warning (_("array element type size does not "
412 "divide object size in cast"));
413 /* FIXME-type-allocation: need a way to free this type when
414 we are done with it. */
415 range_type = create_static_range_type ((struct type *) NULL,
416 TYPE_TARGET_TYPE (range_type),
417 low_bound,
418 new_length + low_bound - 1);
419 deprecated_set_value_type (arg2,
420 create_array_type ((struct type *) NULL,
421 element_type,
422 range_type));
423 return arg2;
424 }
425 }
426
427 if (current_language->c_style_arrays
428 && TYPE_CODE (type2) == TYPE_CODE_ARRAY
429 && !TYPE_VECTOR (type2))
430 arg2 = value_coerce_array (arg2);
431
432 if (TYPE_CODE (type2) == TYPE_CODE_FUNC)
433 arg2 = value_coerce_function (arg2);
434
435 type2 = check_typedef (value_type (arg2));
436 code2 = TYPE_CODE (type2);
437
438 if (code1 == TYPE_CODE_COMPLEX)
439 return cast_into_complex (type, arg2);
440 if (code1 == TYPE_CODE_BOOL)
441 {
442 code1 = TYPE_CODE_INT;
443 convert_to_boolean = 1;
444 }
445 if (code1 == TYPE_CODE_CHAR)
446 code1 = TYPE_CODE_INT;
447 if (code2 == TYPE_CODE_BOOL || code2 == TYPE_CODE_CHAR)
448 code2 = TYPE_CODE_INT;
449
450 scalar = (code2 == TYPE_CODE_INT || code2 == TYPE_CODE_FLT
451 || code2 == TYPE_CODE_DECFLOAT || code2 == TYPE_CODE_ENUM
452 || code2 == TYPE_CODE_RANGE);
453
454 if ((code1 == TYPE_CODE_STRUCT || code1 == TYPE_CODE_UNION)
455 && (code2 == TYPE_CODE_STRUCT || code2 == TYPE_CODE_UNION)
456 && TYPE_NAME (type) != 0)
457 {
458 struct value *v = value_cast_structs (type, arg2);
459
460 if (v)
461 return v;
462 }
463
464 if (code1 == TYPE_CODE_FLT && scalar)
465 return value_from_double (type, value_as_double (arg2));
466 else if (code1 == TYPE_CODE_DECFLOAT && scalar)
467 {
468 enum bfd_endian byte_order = gdbarch_byte_order (get_type_arch (type));
469 int dec_len = TYPE_LENGTH (type);
470 gdb_byte dec[16];
471
472 if (code2 == TYPE_CODE_FLT)
473 decimal_from_floating (arg2, dec, dec_len, byte_order);
474 else if (code2 == TYPE_CODE_DECFLOAT)
475 decimal_convert (value_contents (arg2), TYPE_LENGTH (type2),
476 byte_order, dec, dec_len, byte_order);
477 else
478 /* The only option left is an integral type. */
479 decimal_from_integral (arg2, dec, dec_len, byte_order);
480
481 return value_from_decfloat (type, dec);
482 }
483 else if ((code1 == TYPE_CODE_INT || code1 == TYPE_CODE_ENUM
484 || code1 == TYPE_CODE_RANGE)
485 && (scalar || code2 == TYPE_CODE_PTR
486 || code2 == TYPE_CODE_MEMBERPTR))
487 {
488 LONGEST longest;
489
490 /* When we cast pointers to integers, we mustn't use
491 gdbarch_pointer_to_address to find the address the pointer
492 represents, as value_as_long would. GDB should evaluate
493 expressions just as the compiler would --- and the compiler
494 sees a cast as a simple reinterpretation of the pointer's
495 bits. */
496 if (code2 == TYPE_CODE_PTR)
497 longest = extract_unsigned_integer
498 (value_contents (arg2), TYPE_LENGTH (type2),
499 gdbarch_byte_order (get_type_arch (type2)));
500 else
501 longest = value_as_long (arg2);
502 return value_from_longest (type, convert_to_boolean ?
503 (LONGEST) (longest ? 1 : 0) : longest);
504 }
505 else if (code1 == TYPE_CODE_PTR && (code2 == TYPE_CODE_INT
506 || code2 == TYPE_CODE_ENUM
507 || code2 == TYPE_CODE_RANGE))
508 {
509 /* TYPE_LENGTH (type) is the length of a pointer, but we really
510 want the length of an address! -- we are really dealing with
511 addresses (i.e., gdb representations) not pointers (i.e.,
512 target representations) here.
513
514 This allows things like "print *(int *)0x01000234" to work
515 without printing a misleading message -- which would
516 otherwise occur when dealing with a target having two byte
517 pointers and four byte addresses. */
518
519 int addr_bit = gdbarch_addr_bit (get_type_arch (type2));
520 LONGEST longest = value_as_long (arg2);
521
522 if (addr_bit < sizeof (LONGEST) * HOST_CHAR_BIT)
523 {
524 if (longest >= ((LONGEST) 1 << addr_bit)
525 || longest <= -((LONGEST) 1 << addr_bit))
526 warning (_("value truncated"));
527 }
528 return value_from_longest (type, longest);
529 }
530 else if (code1 == TYPE_CODE_METHODPTR && code2 == TYPE_CODE_INT
531 && value_as_long (arg2) == 0)
532 {
533 struct value *result = allocate_value (type);
534
535 cplus_make_method_ptr (type, value_contents_writeable (result), 0, 0);
536 return result;
537 }
538 else if (code1 == TYPE_CODE_MEMBERPTR && code2 == TYPE_CODE_INT
539 && value_as_long (arg2) == 0)
540 {
541 /* The Itanium C++ ABI represents NULL pointers to members as
542 minus one, instead of biasing the normal case. */
543 return value_from_longest (type, -1);
544 }
545 else if (code1 == TYPE_CODE_ARRAY && TYPE_VECTOR (type)
546 && code2 == TYPE_CODE_ARRAY && TYPE_VECTOR (type2)
547 && TYPE_LENGTH (type) != TYPE_LENGTH (type2))
548 error (_("Cannot convert between vector values of different sizes"));
549 else if (code1 == TYPE_CODE_ARRAY && TYPE_VECTOR (type) && scalar
550 && TYPE_LENGTH (type) != TYPE_LENGTH (type2))
551 error (_("can only cast scalar to vector of same size"));
552 else if (code1 == TYPE_CODE_VOID)
553 {
554 return value_zero (type, not_lval);
555 }
556 else if (TYPE_LENGTH (type) == TYPE_LENGTH (type2))
557 {
558 if (code1 == TYPE_CODE_PTR && code2 == TYPE_CODE_PTR)
559 return value_cast_pointers (type, arg2, 0);
560
561 arg2 = value_copy (arg2);
562 deprecated_set_value_type (arg2, type);
563 set_value_enclosing_type (arg2, type);
564 set_value_pointed_to_offset (arg2, 0); /* pai: chk_val */
565 return arg2;
566 }
567 else if (VALUE_LVAL (arg2) == lval_memory)
568 return value_at_lazy (type, value_address (arg2));
569 else
570 {
571 error (_("Invalid cast."));
572 return 0;
573 }
574 }
575
576 /* The C++ reinterpret_cast operator. */
577
578 struct value *
579 value_reinterpret_cast (struct type *type, struct value *arg)
580 {
581 struct value *result;
582 struct type *real_type = check_typedef (type);
583 struct type *arg_type, *dest_type;
584 int is_ref = 0;
585 enum type_code dest_code, arg_code;
586
587 /* Do reference, function, and array conversion. */
588 arg = coerce_array (arg);
589
590 /* Attempt to preserve the type the user asked for. */
591 dest_type = type;
592
593 /* If we are casting to a reference type, transform
594 reinterpret_cast<T&>(V) to *reinterpret_cast<T*>(&V). */
595 if (TYPE_CODE (real_type) == TYPE_CODE_REF)
596 {
597 is_ref = 1;
598 arg = value_addr (arg);
599 dest_type = lookup_pointer_type (TYPE_TARGET_TYPE (dest_type));
600 real_type = lookup_pointer_type (real_type);
601 }
602
603 arg_type = value_type (arg);
604
605 dest_code = TYPE_CODE (real_type);
606 arg_code = TYPE_CODE (arg_type);
607
608 /* We can convert pointer types, or any pointer type to int, or int
609 type to pointer. */
610 if ((dest_code == TYPE_CODE_PTR && arg_code == TYPE_CODE_INT)
611 || (dest_code == TYPE_CODE_INT && arg_code == TYPE_CODE_PTR)
612 || (dest_code == TYPE_CODE_METHODPTR && arg_code == TYPE_CODE_INT)
613 || (dest_code == TYPE_CODE_INT && arg_code == TYPE_CODE_METHODPTR)
614 || (dest_code == TYPE_CODE_MEMBERPTR && arg_code == TYPE_CODE_INT)
615 || (dest_code == TYPE_CODE_INT && arg_code == TYPE_CODE_MEMBERPTR)
616 || (dest_code == arg_code
617 && (dest_code == TYPE_CODE_PTR
618 || dest_code == TYPE_CODE_METHODPTR
619 || dest_code == TYPE_CODE_MEMBERPTR)))
620 result = value_cast (dest_type, arg);
621 else
622 error (_("Invalid reinterpret_cast"));
623
624 if (is_ref)
625 result = value_cast (type, value_ref (value_ind (result)));
626
627 return result;
628 }
629
630 /* A helper for value_dynamic_cast. This implements the first of two
631 runtime checks: we iterate over all the base classes of the value's
632 class which are equal to the desired class; if only one of these
633 holds the value, then it is the answer. */
634
635 static int
636 dynamic_cast_check_1 (struct type *desired_type,
637 const gdb_byte *valaddr,
638 int embedded_offset,
639 CORE_ADDR address,
640 struct value *val,
641 struct type *search_type,
642 CORE_ADDR arg_addr,
643 struct type *arg_type,
644 struct value **result)
645 {
646 int i, result_count = 0;
647
648 for (i = 0; i < TYPE_N_BASECLASSES (search_type) && result_count < 2; ++i)
649 {
650 int offset = baseclass_offset (search_type, i, valaddr, embedded_offset,
651 address, val);
652
653 if (class_types_same_p (desired_type, TYPE_BASECLASS (search_type, i)))
654 {
655 if (address + embedded_offset + offset >= arg_addr
656 && address + embedded_offset + offset < arg_addr + TYPE_LENGTH (arg_type))
657 {
658 ++result_count;
659 if (!*result)
660 *result = value_at_lazy (TYPE_BASECLASS (search_type, i),
661 address + embedded_offset + offset);
662 }
663 }
664 else
665 result_count += dynamic_cast_check_1 (desired_type,
666 valaddr,
667 embedded_offset + offset,
668 address, val,
669 TYPE_BASECLASS (search_type, i),
670 arg_addr,
671 arg_type,
672 result);
673 }
674
675 return result_count;
676 }
677
678 /* A helper for value_dynamic_cast. This implements the second of two
679 runtime checks: we look for a unique public sibling class of the
680 argument's declared class. */
681
682 static int
683 dynamic_cast_check_2 (struct type *desired_type,
684 const gdb_byte *valaddr,
685 int embedded_offset,
686 CORE_ADDR address,
687 struct value *val,
688 struct type *search_type,
689 struct value **result)
690 {
691 int i, result_count = 0;
692
693 for (i = 0; i < TYPE_N_BASECLASSES (search_type) && result_count < 2; ++i)
694 {
695 int offset;
696
697 if (! BASETYPE_VIA_PUBLIC (search_type, i))
698 continue;
699
700 offset = baseclass_offset (search_type, i, valaddr, embedded_offset,
701 address, val);
702 if (class_types_same_p (desired_type, TYPE_BASECLASS (search_type, i)))
703 {
704 ++result_count;
705 if (*result == NULL)
706 *result = value_at_lazy (TYPE_BASECLASS (search_type, i),
707 address + embedded_offset + offset);
708 }
709 else
710 result_count += dynamic_cast_check_2 (desired_type,
711 valaddr,
712 embedded_offset + offset,
713 address, val,
714 TYPE_BASECLASS (search_type, i),
715 result);
716 }
717
718 return result_count;
719 }
720
721 /* The C++ dynamic_cast operator. */
722
723 struct value *
724 value_dynamic_cast (struct type *type, struct value *arg)
725 {
726 int full, top, using_enc;
727 struct type *resolved_type = check_typedef (type);
728 struct type *arg_type = check_typedef (value_type (arg));
729 struct type *class_type, *rtti_type;
730 struct value *result, *tem, *original_arg = arg;
731 CORE_ADDR addr;
732 int is_ref = TYPE_CODE (resolved_type) == TYPE_CODE_REF;
733
734 if (TYPE_CODE (resolved_type) != TYPE_CODE_PTR
735 && TYPE_CODE (resolved_type) != TYPE_CODE_REF)
736 error (_("Argument to dynamic_cast must be a pointer or reference type"));
737 if (TYPE_CODE (TYPE_TARGET_TYPE (resolved_type)) != TYPE_CODE_VOID
738 && TYPE_CODE (TYPE_TARGET_TYPE (resolved_type)) != TYPE_CODE_STRUCT)
739 error (_("Argument to dynamic_cast must be pointer to class or `void *'"));
740
741 class_type = check_typedef (TYPE_TARGET_TYPE (resolved_type));
742 if (TYPE_CODE (resolved_type) == TYPE_CODE_PTR)
743 {
744 if (TYPE_CODE (arg_type) != TYPE_CODE_PTR
745 && ! (TYPE_CODE (arg_type) == TYPE_CODE_INT
746 && value_as_long (arg) == 0))
747 error (_("Argument to dynamic_cast does not have pointer type"));
748 if (TYPE_CODE (arg_type) == TYPE_CODE_PTR)
749 {
750 arg_type = check_typedef (TYPE_TARGET_TYPE (arg_type));
751 if (TYPE_CODE (arg_type) != TYPE_CODE_STRUCT)
752 error (_("Argument to dynamic_cast does "
753 "not have pointer to class type"));
754 }
755
756 /* Handle NULL pointers. */
757 if (value_as_long (arg) == 0)
758 return value_zero (type, not_lval);
759
760 arg = value_ind (arg);
761 }
762 else
763 {
764 if (TYPE_CODE (arg_type) != TYPE_CODE_STRUCT)
765 error (_("Argument to dynamic_cast does not have class type"));
766 }
767
768 /* If the classes are the same, just return the argument. */
769 if (class_types_same_p (class_type, arg_type))
770 return value_cast (type, arg);
771
772 /* If the target type is a unique base class of the argument's
773 declared type, just cast it. */
774 if (is_ancestor (class_type, arg_type))
775 {
776 if (is_unique_ancestor (class_type, arg))
777 return value_cast (type, original_arg);
778 error (_("Ambiguous dynamic_cast"));
779 }
780
781 rtti_type = value_rtti_type (arg, &full, &top, &using_enc);
782 if (! rtti_type)
783 error (_("Couldn't determine value's most derived type for dynamic_cast"));
784
785 /* Compute the most derived object's address. */
786 addr = value_address (arg);
787 if (full)
788 {
789 /* Done. */
790 }
791 else if (using_enc)
792 addr += top;
793 else
794 addr += top + value_embedded_offset (arg);
795
796 /* dynamic_cast<void *> means to return a pointer to the
797 most-derived object. */
798 if (TYPE_CODE (resolved_type) == TYPE_CODE_PTR
799 && TYPE_CODE (TYPE_TARGET_TYPE (resolved_type)) == TYPE_CODE_VOID)
800 return value_at_lazy (type, addr);
801
802 tem = value_at (type, addr);
803 type = value_type (tem);
804
805 /* The first dynamic check specified in 5.2.7. */
806 if (is_public_ancestor (arg_type, TYPE_TARGET_TYPE (resolved_type)))
807 {
808 if (class_types_same_p (rtti_type, TYPE_TARGET_TYPE (resolved_type)))
809 return tem;
810 result = NULL;
811 if (dynamic_cast_check_1 (TYPE_TARGET_TYPE (resolved_type),
812 value_contents_for_printing (tem),
813 value_embedded_offset (tem),
814 value_address (tem), tem,
815 rtti_type, addr,
816 arg_type,
817 &result) == 1)
818 return value_cast (type,
819 is_ref ? value_ref (result) : value_addr (result));
820 }
821
822 /* The second dynamic check specified in 5.2.7. */
823 result = NULL;
824 if (is_public_ancestor (arg_type, rtti_type)
825 && dynamic_cast_check_2 (TYPE_TARGET_TYPE (resolved_type),
826 value_contents_for_printing (tem),
827 value_embedded_offset (tem),
828 value_address (tem), tem,
829 rtti_type, &result) == 1)
830 return value_cast (type,
831 is_ref ? value_ref (result) : value_addr (result));
832
833 if (TYPE_CODE (resolved_type) == TYPE_CODE_PTR)
834 return value_zero (type, not_lval);
835
836 error (_("dynamic_cast failed"));
837 }
838
839 /* Create a value of type TYPE that is zero, and return it. */
840
841 struct value *
842 value_zero (struct type *type, enum lval_type lv)
843 {
844 struct value *val = allocate_value (type);
845
846 VALUE_LVAL (val) = (lv == lval_computed ? not_lval : lv);
847 return val;
848 }
849
850 /* Create a not_lval value of numeric type TYPE that is one, and return it. */
851
852 struct value *
853 value_one (struct type *type)
854 {
855 struct type *type1 = check_typedef (type);
856 struct value *val;
857
858 if (TYPE_CODE (type1) == TYPE_CODE_DECFLOAT)
859 {
860 enum bfd_endian byte_order = gdbarch_byte_order (get_type_arch (type));
861 gdb_byte v[16];
862
863 decimal_from_string (v, TYPE_LENGTH (type), byte_order, "1");
864 val = value_from_decfloat (type, v);
865 }
866 else if (TYPE_CODE (type1) == TYPE_CODE_FLT)
867 {
868 val = value_from_double (type, (DOUBLEST) 1);
869 }
870 else if (is_integral_type (type1))
871 {
872 val = value_from_longest (type, (LONGEST) 1);
873 }
874 else if (TYPE_CODE (type1) == TYPE_CODE_ARRAY && TYPE_VECTOR (type1))
875 {
876 struct type *eltype = check_typedef (TYPE_TARGET_TYPE (type1));
877 int i;
878 LONGEST low_bound, high_bound;
879 struct value *tmp;
880
881 if (!get_array_bounds (type1, &low_bound, &high_bound))
882 error (_("Could not determine the vector bounds"));
883
884 val = allocate_value (type);
885 for (i = 0; i < high_bound - low_bound + 1; i++)
886 {
887 tmp = value_one (eltype);
888 memcpy (value_contents_writeable (val) + i * TYPE_LENGTH (eltype),
889 value_contents_all (tmp), TYPE_LENGTH (eltype));
890 }
891 }
892 else
893 {
894 error (_("Not a numeric type."));
895 }
896
897 /* value_one result is never used for assignments to. */
898 gdb_assert (VALUE_LVAL (val) == not_lval);
899
900 return val;
901 }
902
903 /* Helper function for value_at, value_at_lazy, and value_at_lazy_stack.
904 The type of the created value may differ from the passed type TYPE.
905 Make sure to retrieve the returned values's new type after this call
906 e.g. in case the type is a variable length array. */
907
908 static struct value *
909 get_value_at (struct type *type, CORE_ADDR addr, int lazy)
910 {
911 struct value *val;
912
913 if (TYPE_CODE (check_typedef (type)) == TYPE_CODE_VOID)
914 error (_("Attempt to dereference a generic pointer."));
915
916 val = value_from_contents_and_address (type, NULL, addr);
917
918 if (!lazy)
919 value_fetch_lazy (val);
920
921 return val;
922 }
923
924 /* Return a value with type TYPE located at ADDR.
925
926 Call value_at only if the data needs to be fetched immediately;
927 if we can be 'lazy' and defer the fetch, perhaps indefinately, call
928 value_at_lazy instead. value_at_lazy simply records the address of
929 the data and sets the lazy-evaluation-required flag. The lazy flag
930 is tested in the value_contents macro, which is used if and when
931 the contents are actually required. The type of the created value
932 may differ from the passed type TYPE. Make sure to retrieve the
933 returned values's new type after this call e.g. in case the type
934 is a variable length array.
935
936 Note: value_at does *NOT* handle embedded offsets; perform such
937 adjustments before or after calling it. */
938
939 struct value *
940 value_at (struct type *type, CORE_ADDR addr)
941 {
942 return get_value_at (type, addr, 0);
943 }
944
945 /* Return a lazy value with type TYPE located at ADDR (cf. value_at).
946 The type of the created value may differ from the passed type TYPE.
947 Make sure to retrieve the returned values's new type after this call
948 e.g. in case the type is a variable length array. */
949
950 struct value *
951 value_at_lazy (struct type *type, CORE_ADDR addr)
952 {
953 return get_value_at (type, addr, 1);
954 }
955
956 void
957 read_value_memory (struct value *val, int embedded_offset,
958 int stack, CORE_ADDR memaddr,
959 gdb_byte *buffer, size_t length)
960 {
961 ULONGEST xfered = 0;
962
963 while (xfered < length)
964 {
965 enum target_xfer_status status;
966 ULONGEST xfered_len;
967
968 status = target_xfer_partial (current_target.beneath,
969 TARGET_OBJECT_MEMORY, NULL,
970 buffer + xfered, NULL,
971 memaddr + xfered, length - xfered,
972 &xfered_len);
973
974 if (status == TARGET_XFER_OK)
975 /* nothing */;
976 else if (status == TARGET_XFER_UNAVAILABLE)
977 mark_value_bytes_unavailable (val, embedded_offset + xfered,
978 xfered_len);
979 else if (status == TARGET_XFER_EOF)
980 memory_error (TARGET_XFER_E_IO, memaddr + xfered);
981 else
982 memory_error (status, memaddr + xfered);
983
984 xfered += xfered_len;
985 QUIT;
986 }
987 }
988
989 /* Store the contents of FROMVAL into the location of TOVAL.
990 Return a new value with the location of TOVAL and contents of FROMVAL. */
991
992 struct value *
993 value_assign (struct value *toval, struct value *fromval)
994 {
995 struct type *type;
996 struct value *val;
997 struct frame_id old_frame;
998
999 if (!deprecated_value_modifiable (toval))
1000 error (_("Left operand of assignment is not a modifiable lvalue."));
1001
1002 toval = coerce_ref (toval);
1003
1004 type = value_type (toval);
1005 if (VALUE_LVAL (toval) != lval_internalvar)
1006 fromval = value_cast (type, fromval);
1007 else
1008 {
1009 /* Coerce arrays and functions to pointers, except for arrays
1010 which only live in GDB's storage. */
1011 if (!value_must_coerce_to_target (fromval))
1012 fromval = coerce_array (fromval);
1013 }
1014
1015 CHECK_TYPEDEF (type);
1016
1017 /* Since modifying a register can trash the frame chain, and
1018 modifying memory can trash the frame cache, we save the old frame
1019 and then restore the new frame afterwards. */
1020 old_frame = get_frame_id (deprecated_safe_get_selected_frame ());
1021
1022 switch (VALUE_LVAL (toval))
1023 {
1024 case lval_internalvar:
1025 set_internalvar (VALUE_INTERNALVAR (toval), fromval);
1026 return value_of_internalvar (get_type_arch (type),
1027 VALUE_INTERNALVAR (toval));
1028
1029 case lval_internalvar_component:
1030 {
1031 int offset = value_offset (toval);
1032
1033 /* Are we dealing with a bitfield?
1034
1035 It is important to mention that `value_parent (toval)' is
1036 non-NULL iff `value_bitsize (toval)' is non-zero. */
1037 if (value_bitsize (toval))
1038 {
1039 /* VALUE_INTERNALVAR below refers to the parent value, while
1040 the offset is relative to this parent value. */
1041 gdb_assert (value_parent (value_parent (toval)) == NULL);
1042 offset += value_offset (value_parent (toval));
1043 }
1044
1045 set_internalvar_component (VALUE_INTERNALVAR (toval),
1046 offset,
1047 value_bitpos (toval),
1048 value_bitsize (toval),
1049 fromval);
1050 }
1051 break;
1052
1053 case lval_memory:
1054 {
1055 const gdb_byte *dest_buffer;
1056 CORE_ADDR changed_addr;
1057 int changed_len;
1058 gdb_byte buffer[sizeof (LONGEST)];
1059
1060 if (value_bitsize (toval))
1061 {
1062 struct value *parent = value_parent (toval);
1063
1064 changed_addr = value_address (parent) + value_offset (toval);
1065 changed_len = (value_bitpos (toval)
1066 + value_bitsize (toval)
1067 + HOST_CHAR_BIT - 1)
1068 / HOST_CHAR_BIT;
1069
1070 /* If we can read-modify-write exactly the size of the
1071 containing type (e.g. short or int) then do so. This
1072 is safer for volatile bitfields mapped to hardware
1073 registers. */
1074 if (changed_len < TYPE_LENGTH (type)
1075 && TYPE_LENGTH (type) <= (int) sizeof (LONGEST)
1076 && ((LONGEST) changed_addr % TYPE_LENGTH (type)) == 0)
1077 changed_len = TYPE_LENGTH (type);
1078
1079 if (changed_len > (int) sizeof (LONGEST))
1080 error (_("Can't handle bitfields which "
1081 "don't fit in a %d bit word."),
1082 (int) sizeof (LONGEST) * HOST_CHAR_BIT);
1083
1084 read_memory (changed_addr, buffer, changed_len);
1085 modify_field (type, buffer, value_as_long (fromval),
1086 value_bitpos (toval), value_bitsize (toval));
1087 dest_buffer = buffer;
1088 }
1089 else
1090 {
1091 changed_addr = value_address (toval);
1092 changed_len = TYPE_LENGTH (type);
1093 dest_buffer = value_contents (fromval);
1094 }
1095
1096 write_memory_with_notification (changed_addr, dest_buffer, changed_len);
1097 }
1098 break;
1099
1100 case lval_register:
1101 {
1102 struct frame_info *frame;
1103 struct gdbarch *gdbarch;
1104 int value_reg;
1105
1106 /* Figure out which frame this is in currently. */
1107 frame = frame_find_by_id (VALUE_FRAME_ID (toval));
1108 value_reg = VALUE_REGNUM (toval);
1109
1110 if (!frame)
1111 error (_("Value being assigned to is no longer active."));
1112
1113 gdbarch = get_frame_arch (frame);
1114
1115 if (value_bitsize (toval))
1116 {
1117 struct value *parent = value_parent (toval);
1118 int offset = value_offset (parent) + value_offset (toval);
1119 int changed_len;
1120 gdb_byte buffer[sizeof (LONGEST)];
1121 int optim, unavail;
1122
1123 changed_len = (value_bitpos (toval)
1124 + value_bitsize (toval)
1125 + HOST_CHAR_BIT - 1)
1126 / HOST_CHAR_BIT;
1127
1128 if (changed_len > (int) sizeof (LONGEST))
1129 error (_("Can't handle bitfields which "
1130 "don't fit in a %d bit word."),
1131 (int) sizeof (LONGEST) * HOST_CHAR_BIT);
1132
1133 if (!get_frame_register_bytes (frame, value_reg, offset,
1134 changed_len, buffer,
1135 &optim, &unavail))
1136 {
1137 if (optim)
1138 throw_error (OPTIMIZED_OUT_ERROR,
1139 _("value has been optimized out"));
1140 if (unavail)
1141 throw_error (NOT_AVAILABLE_ERROR,
1142 _("value is not available"));
1143 }
1144
1145 modify_field (type, buffer, value_as_long (fromval),
1146 value_bitpos (toval), value_bitsize (toval));
1147
1148 put_frame_register_bytes (frame, value_reg, offset,
1149 changed_len, buffer);
1150 }
1151 else
1152 {
1153 if (gdbarch_convert_register_p (gdbarch, VALUE_REGNUM (toval),
1154 type))
1155 {
1156 /* If TOVAL is a special machine register requiring
1157 conversion of program values to a special raw
1158 format. */
1159 gdbarch_value_to_register (gdbarch, frame,
1160 VALUE_REGNUM (toval), type,
1161 value_contents (fromval));
1162 }
1163 else
1164 {
1165 put_frame_register_bytes (frame, value_reg,
1166 value_offset (toval),
1167 TYPE_LENGTH (type),
1168 value_contents (fromval));
1169 }
1170 }
1171
1172 observer_notify_register_changed (frame, value_reg);
1173 if (deprecated_register_changed_hook)
1174 deprecated_register_changed_hook (-1);
1175 break;
1176 }
1177
1178 case lval_computed:
1179 {
1180 const struct lval_funcs *funcs = value_computed_funcs (toval);
1181
1182 if (funcs->write != NULL)
1183 {
1184 funcs->write (toval, fromval);
1185 break;
1186 }
1187 }
1188 /* Fall through. */
1189
1190 default:
1191 error (_("Left operand of assignment is not an lvalue."));
1192 }
1193
1194 /* Assigning to the stack pointer, frame pointer, and other
1195 (architecture and calling convention specific) registers may
1196 cause the frame cache and regcache to be out of date. Assigning to memory
1197 also can. We just do this on all assignments to registers or
1198 memory, for simplicity's sake; I doubt the slowdown matters. */
1199 switch (VALUE_LVAL (toval))
1200 {
1201 case lval_memory:
1202 case lval_register:
1203 case lval_computed:
1204
1205 observer_notify_target_changed (&current_target);
1206
1207 /* Having destroyed the frame cache, restore the selected
1208 frame. */
1209
1210 /* FIXME: cagney/2002-11-02: There has to be a better way of
1211 doing this. Instead of constantly saving/restoring the
1212 frame. Why not create a get_selected_frame() function that,
1213 having saved the selected frame's ID can automatically
1214 re-find the previously selected frame automatically. */
1215
1216 {
1217 struct frame_info *fi = frame_find_by_id (old_frame);
1218
1219 if (fi != NULL)
1220 select_frame (fi);
1221 }
1222
1223 break;
1224 default:
1225 break;
1226 }
1227
1228 /* If the field does not entirely fill a LONGEST, then zero the sign
1229 bits. If the field is signed, and is negative, then sign
1230 extend. */
1231 if ((value_bitsize (toval) > 0)
1232 && (value_bitsize (toval) < 8 * (int) sizeof (LONGEST)))
1233 {
1234 LONGEST fieldval = value_as_long (fromval);
1235 LONGEST valmask = (((ULONGEST) 1) << value_bitsize (toval)) - 1;
1236
1237 fieldval &= valmask;
1238 if (!TYPE_UNSIGNED (type)
1239 && (fieldval & (valmask ^ (valmask >> 1))))
1240 fieldval |= ~valmask;
1241
1242 fromval = value_from_longest (type, fieldval);
1243 }
1244
1245 /* The return value is a copy of TOVAL so it shares its location
1246 information, but its contents are updated from FROMVAL. This
1247 implies the returned value is not lazy, even if TOVAL was. */
1248 val = value_copy (toval);
1249 set_value_lazy (val, 0);
1250 memcpy (value_contents_raw (val), value_contents (fromval),
1251 TYPE_LENGTH (type));
1252
1253 /* We copy over the enclosing type and pointed-to offset from FROMVAL
1254 in the case of pointer types. For object types, the enclosing type
1255 and embedded offset must *not* be copied: the target object refered
1256 to by TOVAL retains its original dynamic type after assignment. */
1257 if (TYPE_CODE (type) == TYPE_CODE_PTR)
1258 {
1259 set_value_enclosing_type (val, value_enclosing_type (fromval));
1260 set_value_pointed_to_offset (val, value_pointed_to_offset (fromval));
1261 }
1262
1263 return val;
1264 }
1265
1266 /* Extend a value VAL to COUNT repetitions of its type. */
1267
1268 struct value *
1269 value_repeat (struct value *arg1, int count)
1270 {
1271 struct value *val;
1272
1273 if (VALUE_LVAL (arg1) != lval_memory)
1274 error (_("Only values in memory can be extended with '@'."));
1275 if (count < 1)
1276 error (_("Invalid number %d of repetitions."), count);
1277
1278 val = allocate_repeat_value (value_enclosing_type (arg1), count);
1279
1280 VALUE_LVAL (val) = lval_memory;
1281 set_value_address (val, value_address (arg1));
1282
1283 read_value_memory (val, 0, value_stack (val), value_address (val),
1284 value_contents_all_raw (val),
1285 TYPE_LENGTH (value_enclosing_type (val)));
1286
1287 return val;
1288 }
1289
1290 struct value *
1291 value_of_variable (struct symbol *var, const struct block *b)
1292 {
1293 struct frame_info *frame;
1294
1295 if (!symbol_read_needs_frame (var))
1296 frame = NULL;
1297 else if (!b)
1298 frame = get_selected_frame (_("No frame selected."));
1299 else
1300 {
1301 frame = block_innermost_frame (b);
1302 if (!frame)
1303 {
1304 if (BLOCK_FUNCTION (b) && !block_inlined_p (b)
1305 && SYMBOL_PRINT_NAME (BLOCK_FUNCTION (b)))
1306 error (_("No frame is currently executing in block %s."),
1307 SYMBOL_PRINT_NAME (BLOCK_FUNCTION (b)));
1308 else
1309 error (_("No frame is currently executing in specified block"));
1310 }
1311 }
1312
1313 return read_var_value (var, frame);
1314 }
1315
1316 struct value *
1317 address_of_variable (struct symbol *var, const struct block *b)
1318 {
1319 struct type *type = SYMBOL_TYPE (var);
1320 struct value *val;
1321
1322 /* Evaluate it first; if the result is a memory address, we're fine.
1323 Lazy evaluation pays off here. */
1324
1325 val = value_of_variable (var, b);
1326 type = value_type (val);
1327
1328 if ((VALUE_LVAL (val) == lval_memory && value_lazy (val))
1329 || TYPE_CODE (type) == TYPE_CODE_FUNC)
1330 {
1331 CORE_ADDR addr = value_address (val);
1332
1333 return value_from_pointer (lookup_pointer_type (type), addr);
1334 }
1335
1336 /* Not a memory address; check what the problem was. */
1337 switch (VALUE_LVAL (val))
1338 {
1339 case lval_register:
1340 {
1341 struct frame_info *frame;
1342 const char *regname;
1343
1344 frame = frame_find_by_id (VALUE_FRAME_ID (val));
1345 gdb_assert (frame);
1346
1347 regname = gdbarch_register_name (get_frame_arch (frame),
1348 VALUE_REGNUM (val));
1349 gdb_assert (regname && *regname);
1350
1351 error (_("Address requested for identifier "
1352 "\"%s\" which is in register $%s"),
1353 SYMBOL_PRINT_NAME (var), regname);
1354 break;
1355 }
1356
1357 default:
1358 error (_("Can't take address of \"%s\" which isn't an lvalue."),
1359 SYMBOL_PRINT_NAME (var));
1360 break;
1361 }
1362
1363 return val;
1364 }
1365
1366 /* Return one if VAL does not live in target memory, but should in order
1367 to operate on it. Otherwise return zero. */
1368
1369 int
1370 value_must_coerce_to_target (struct value *val)
1371 {
1372 struct type *valtype;
1373
1374 /* The only lval kinds which do not live in target memory. */
1375 if (VALUE_LVAL (val) != not_lval
1376 && VALUE_LVAL (val) != lval_internalvar
1377 && VALUE_LVAL (val) != lval_xcallable)
1378 return 0;
1379
1380 valtype = check_typedef (value_type (val));
1381
1382 switch (TYPE_CODE (valtype))
1383 {
1384 case TYPE_CODE_ARRAY:
1385 return TYPE_VECTOR (valtype) ? 0 : 1;
1386 case TYPE_CODE_STRING:
1387 return 1;
1388 default:
1389 return 0;
1390 }
1391 }
1392
1393 /* Make sure that VAL lives in target memory if it's supposed to. For
1394 instance, strings are constructed as character arrays in GDB's
1395 storage, and this function copies them to the target. */
1396
1397 struct value *
1398 value_coerce_to_target (struct value *val)
1399 {
1400 LONGEST length;
1401 CORE_ADDR addr;
1402
1403 if (!value_must_coerce_to_target (val))
1404 return val;
1405
1406 length = TYPE_LENGTH (check_typedef (value_type (val)));
1407 addr = allocate_space_in_inferior (length);
1408 write_memory (addr, value_contents (val), length);
1409 return value_at_lazy (value_type (val), addr);
1410 }
1411
1412 /* Given a value which is an array, return a value which is a pointer
1413 to its first element, regardless of whether or not the array has a
1414 nonzero lower bound.
1415
1416 FIXME: A previous comment here indicated that this routine should
1417 be substracting the array's lower bound. It's not clear to me that
1418 this is correct. Given an array subscripting operation, it would
1419 certainly work to do the adjustment here, essentially computing:
1420
1421 (&array[0] - (lowerbound * sizeof array[0])) + (index * sizeof array[0])
1422
1423 However I believe a more appropriate and logical place to account
1424 for the lower bound is to do so in value_subscript, essentially
1425 computing:
1426
1427 (&array[0] + ((index - lowerbound) * sizeof array[0]))
1428
1429 As further evidence consider what would happen with operations
1430 other than array subscripting, where the caller would get back a
1431 value that had an address somewhere before the actual first element
1432 of the array, and the information about the lower bound would be
1433 lost because of the coercion to pointer type. */
1434
1435 struct value *
1436 value_coerce_array (struct value *arg1)
1437 {
1438 struct type *type = check_typedef (value_type (arg1));
1439
1440 /* If the user tries to do something requiring a pointer with an
1441 array that has not yet been pushed to the target, then this would
1442 be a good time to do so. */
1443 arg1 = value_coerce_to_target (arg1);
1444
1445 if (VALUE_LVAL (arg1) != lval_memory)
1446 error (_("Attempt to take address of value not located in memory."));
1447
1448 return value_from_pointer (lookup_pointer_type (TYPE_TARGET_TYPE (type)),
1449 value_address (arg1));
1450 }
1451
1452 /* Given a value which is a function, return a value which is a pointer
1453 to it. */
1454
1455 struct value *
1456 value_coerce_function (struct value *arg1)
1457 {
1458 struct value *retval;
1459
1460 if (VALUE_LVAL (arg1) != lval_memory)
1461 error (_("Attempt to take address of value not located in memory."));
1462
1463 retval = value_from_pointer (lookup_pointer_type (value_type (arg1)),
1464 value_address (arg1));
1465 return retval;
1466 }
1467
1468 /* Return a pointer value for the object for which ARG1 is the
1469 contents. */
1470
1471 struct value *
1472 value_addr (struct value *arg1)
1473 {
1474 struct value *arg2;
1475 struct type *type = check_typedef (value_type (arg1));
1476
1477 if (TYPE_CODE (type) == TYPE_CODE_REF)
1478 {
1479 /* Copy the value, but change the type from (T&) to (T*). We
1480 keep the same location information, which is efficient, and
1481 allows &(&X) to get the location containing the reference. */
1482 arg2 = value_copy (arg1);
1483 deprecated_set_value_type (arg2,
1484 lookup_pointer_type (TYPE_TARGET_TYPE (type)));
1485 return arg2;
1486 }
1487 if (TYPE_CODE (type) == TYPE_CODE_FUNC)
1488 return value_coerce_function (arg1);
1489
1490 /* If this is an array that has not yet been pushed to the target,
1491 then this would be a good time to force it to memory. */
1492 arg1 = value_coerce_to_target (arg1);
1493
1494 if (VALUE_LVAL (arg1) != lval_memory)
1495 error (_("Attempt to take address of value not located in memory."));
1496
1497 /* Get target memory address. */
1498 arg2 = value_from_pointer (lookup_pointer_type (value_type (arg1)),
1499 (value_address (arg1)
1500 + value_embedded_offset (arg1)));
1501
1502 /* This may be a pointer to a base subobject; so remember the
1503 full derived object's type ... */
1504 set_value_enclosing_type (arg2,
1505 lookup_pointer_type (value_enclosing_type (arg1)));
1506 /* ... and also the relative position of the subobject in the full
1507 object. */
1508 set_value_pointed_to_offset (arg2, value_embedded_offset (arg1));
1509 return arg2;
1510 }
1511
1512 /* Return a reference value for the object for which ARG1 is the
1513 contents. */
1514
1515 struct value *
1516 value_ref (struct value *arg1)
1517 {
1518 struct value *arg2;
1519 struct type *type = check_typedef (value_type (arg1));
1520
1521 if (TYPE_CODE (type) == TYPE_CODE_REF)
1522 return arg1;
1523
1524 arg2 = value_addr (arg1);
1525 deprecated_set_value_type (arg2, lookup_reference_type (type));
1526 return arg2;
1527 }
1528
1529 /* Given a value of a pointer type, apply the C unary * operator to
1530 it. */
1531
1532 struct value *
1533 value_ind (struct value *arg1)
1534 {
1535 struct type *base_type;
1536 struct value *arg2;
1537
1538 arg1 = coerce_array (arg1);
1539
1540 base_type = check_typedef (value_type (arg1));
1541
1542 if (VALUE_LVAL (arg1) == lval_computed)
1543 {
1544 const struct lval_funcs *funcs = value_computed_funcs (arg1);
1545
1546 if (funcs->indirect)
1547 {
1548 struct value *result = funcs->indirect (arg1);
1549
1550 if (result)
1551 return result;
1552 }
1553 }
1554
1555 if (TYPE_CODE (base_type) == TYPE_CODE_PTR)
1556 {
1557 struct type *enc_type;
1558
1559 /* We may be pointing to something embedded in a larger object.
1560 Get the real type of the enclosing object. */
1561 enc_type = check_typedef (value_enclosing_type (arg1));
1562 enc_type = TYPE_TARGET_TYPE (enc_type);
1563
1564 if (TYPE_CODE (check_typedef (enc_type)) == TYPE_CODE_FUNC
1565 || TYPE_CODE (check_typedef (enc_type)) == TYPE_CODE_METHOD)
1566 /* For functions, go through find_function_addr, which knows
1567 how to handle function descriptors. */
1568 arg2 = value_at_lazy (enc_type,
1569 find_function_addr (arg1, NULL));
1570 else
1571 /* Retrieve the enclosing object pointed to. */
1572 arg2 = value_at_lazy (enc_type,
1573 (value_as_address (arg1)
1574 - value_pointed_to_offset (arg1)));
1575
1576 enc_type = value_type (arg2);
1577 return readjust_indirect_value_type (arg2, enc_type, base_type, arg1);
1578 }
1579
1580 error (_("Attempt to take contents of a non-pointer value."));
1581 return 0; /* For lint -- never reached. */
1582 }
1583 \f
1584 /* Create a value for an array by allocating space in GDB, copying the
1585 data into that space, and then setting up an array value.
1586
1587 The array bounds are set from LOWBOUND and HIGHBOUND, and the array
1588 is populated from the values passed in ELEMVEC.
1589
1590 The element type of the array is inherited from the type of the
1591 first element, and all elements must have the same size (though we
1592 don't currently enforce any restriction on their types). */
1593
1594 struct value *
1595 value_array (int lowbound, int highbound, struct value **elemvec)
1596 {
1597 int nelem;
1598 int idx;
1599 unsigned int typelength;
1600 struct value *val;
1601 struct type *arraytype;
1602
1603 /* Validate that the bounds are reasonable and that each of the
1604 elements have the same size. */
1605
1606 nelem = highbound - lowbound + 1;
1607 if (nelem <= 0)
1608 {
1609 error (_("bad array bounds (%d, %d)"), lowbound, highbound);
1610 }
1611 typelength = TYPE_LENGTH (value_enclosing_type (elemvec[0]));
1612 for (idx = 1; idx < nelem; idx++)
1613 {
1614 if (TYPE_LENGTH (value_enclosing_type (elemvec[idx])) != typelength)
1615 {
1616 error (_("array elements must all be the same size"));
1617 }
1618 }
1619
1620 arraytype = lookup_array_range_type (value_enclosing_type (elemvec[0]),
1621 lowbound, highbound);
1622
1623 if (!current_language->c_style_arrays)
1624 {
1625 val = allocate_value (arraytype);
1626 for (idx = 0; idx < nelem; idx++)
1627 value_contents_copy (val, idx * typelength, elemvec[idx], 0,
1628 typelength);
1629 return val;
1630 }
1631
1632 /* Allocate space to store the array, and then initialize it by
1633 copying in each element. */
1634
1635 val = allocate_value (arraytype);
1636 for (idx = 0; idx < nelem; idx++)
1637 value_contents_copy (val, idx * typelength, elemvec[idx], 0, typelength);
1638 return val;
1639 }
1640
1641 struct value *
1642 value_cstring (char *ptr, ssize_t len, struct type *char_type)
1643 {
1644 struct value *val;
1645 int lowbound = current_language->string_lower_bound;
1646 ssize_t highbound = len / TYPE_LENGTH (char_type);
1647 struct type *stringtype
1648 = lookup_array_range_type (char_type, lowbound, highbound + lowbound - 1);
1649
1650 val = allocate_value (stringtype);
1651 memcpy (value_contents_raw (val), ptr, len);
1652 return val;
1653 }
1654
1655 /* Create a value for a string constant by allocating space in the
1656 inferior, copying the data into that space, and returning the
1657 address with type TYPE_CODE_STRING. PTR points to the string
1658 constant data; LEN is number of characters.
1659
1660 Note that string types are like array of char types with a lower
1661 bound of zero and an upper bound of LEN - 1. Also note that the
1662 string may contain embedded null bytes. */
1663
1664 struct value *
1665 value_string (char *ptr, ssize_t len, struct type *char_type)
1666 {
1667 struct value *val;
1668 int lowbound = current_language->string_lower_bound;
1669 ssize_t highbound = len / TYPE_LENGTH (char_type);
1670 struct type *stringtype
1671 = lookup_string_range_type (char_type, lowbound, highbound + lowbound - 1);
1672
1673 val = allocate_value (stringtype);
1674 memcpy (value_contents_raw (val), ptr, len);
1675 return val;
1676 }
1677
1678 \f
1679 /* See if we can pass arguments in T2 to a function which takes
1680 arguments of types T1. T1 is a list of NARGS arguments, and T2 is
1681 a NULL-terminated vector. If some arguments need coercion of some
1682 sort, then the coerced values are written into T2. Return value is
1683 0 if the arguments could be matched, or the position at which they
1684 differ if not.
1685
1686 STATICP is nonzero if the T1 argument list came from a static
1687 member function. T2 will still include the ``this'' pointer, but
1688 it will be skipped.
1689
1690 For non-static member functions, we ignore the first argument,
1691 which is the type of the instance variable. This is because we
1692 want to handle calls with objects from derived classes. This is
1693 not entirely correct: we should actually check to make sure that a
1694 requested operation is type secure, shouldn't we? FIXME. */
1695
1696 static int
1697 typecmp (int staticp, int varargs, int nargs,
1698 struct field t1[], struct value *t2[])
1699 {
1700 int i;
1701
1702 if (t2 == 0)
1703 internal_error (__FILE__, __LINE__,
1704 _("typecmp: no argument list"));
1705
1706 /* Skip ``this'' argument if applicable. T2 will always include
1707 THIS. */
1708 if (staticp)
1709 t2 ++;
1710
1711 for (i = 0;
1712 (i < nargs) && TYPE_CODE (t1[i].type) != TYPE_CODE_VOID;
1713 i++)
1714 {
1715 struct type *tt1, *tt2;
1716
1717 if (!t2[i])
1718 return i + 1;
1719
1720 tt1 = check_typedef (t1[i].type);
1721 tt2 = check_typedef (value_type (t2[i]));
1722
1723 if (TYPE_CODE (tt1) == TYPE_CODE_REF
1724 /* We should be doing hairy argument matching, as below. */
1725 && (TYPE_CODE (check_typedef (TYPE_TARGET_TYPE (tt1)))
1726 == TYPE_CODE (tt2)))
1727 {
1728 if (TYPE_CODE (tt2) == TYPE_CODE_ARRAY)
1729 t2[i] = value_coerce_array (t2[i]);
1730 else
1731 t2[i] = value_ref (t2[i]);
1732 continue;
1733 }
1734
1735 /* djb - 20000715 - Until the new type structure is in the
1736 place, and we can attempt things like implicit conversions,
1737 we need to do this so you can take something like a map<const
1738 char *>, and properly access map["hello"], because the
1739 argument to [] will be a reference to a pointer to a char,
1740 and the argument will be a pointer to a char. */
1741 while (TYPE_CODE(tt1) == TYPE_CODE_REF
1742 || TYPE_CODE (tt1) == TYPE_CODE_PTR)
1743 {
1744 tt1 = check_typedef( TYPE_TARGET_TYPE(tt1) );
1745 }
1746 while (TYPE_CODE(tt2) == TYPE_CODE_ARRAY
1747 || TYPE_CODE(tt2) == TYPE_CODE_PTR
1748 || TYPE_CODE(tt2) == TYPE_CODE_REF)
1749 {
1750 tt2 = check_typedef (TYPE_TARGET_TYPE(tt2));
1751 }
1752 if (TYPE_CODE (tt1) == TYPE_CODE (tt2))
1753 continue;
1754 /* Array to pointer is a `trivial conversion' according to the
1755 ARM. */
1756
1757 /* We should be doing much hairier argument matching (see
1758 section 13.2 of the ARM), but as a quick kludge, just check
1759 for the same type code. */
1760 if (TYPE_CODE (t1[i].type) != TYPE_CODE (value_type (t2[i])))
1761 return i + 1;
1762 }
1763 if (varargs || t2[i] == NULL)
1764 return 0;
1765 return i + 1;
1766 }
1767
1768 /* Helper class for do_search_struct_field that updates *RESULT_PTR
1769 and *LAST_BOFFSET, and possibly throws an exception if the field
1770 search has yielded ambiguous results. */
1771
1772 static void
1773 update_search_result (struct value **result_ptr, struct value *v,
1774 int *last_boffset, int boffset,
1775 const char *name, struct type *type)
1776 {
1777 if (v != NULL)
1778 {
1779 if (*result_ptr != NULL
1780 /* The result is not ambiguous if all the classes that are
1781 found occupy the same space. */
1782 && *last_boffset != boffset)
1783 error (_("base class '%s' is ambiguous in type '%s'"),
1784 name, TYPE_SAFE_NAME (type));
1785 *result_ptr = v;
1786 *last_boffset = boffset;
1787 }
1788 }
1789
1790 /* A helper for search_struct_field. This does all the work; most
1791 arguments are as passed to search_struct_field. The result is
1792 stored in *RESULT_PTR, which must be initialized to NULL.
1793 OUTERMOST_TYPE is the type of the initial type passed to
1794 search_struct_field; this is used for error reporting when the
1795 lookup is ambiguous. */
1796
1797 static void
1798 do_search_struct_field (const char *name, struct value *arg1, int offset,
1799 struct type *type, int looking_for_baseclass,
1800 struct value **result_ptr,
1801 int *last_boffset,
1802 struct type *outermost_type)
1803 {
1804 int i;
1805 int nbases;
1806
1807 CHECK_TYPEDEF (type);
1808 nbases = TYPE_N_BASECLASSES (type);
1809
1810 if (!looking_for_baseclass)
1811 for (i = TYPE_NFIELDS (type) - 1; i >= nbases; i--)
1812 {
1813 const char *t_field_name = TYPE_FIELD_NAME (type, i);
1814
1815 if (t_field_name && (strcmp_iw (t_field_name, name) == 0))
1816 {
1817 struct value *v;
1818
1819 if (field_is_static (&TYPE_FIELD (type, i)))
1820 v = value_static_field (type, i);
1821 else
1822 v = value_primitive_field (arg1, offset, i, type);
1823 *result_ptr = v;
1824 return;
1825 }
1826
1827 if (t_field_name
1828 && t_field_name[0] == '\0')
1829 {
1830 struct type *field_type = TYPE_FIELD_TYPE (type, i);
1831
1832 if (TYPE_CODE (field_type) == TYPE_CODE_UNION
1833 || TYPE_CODE (field_type) == TYPE_CODE_STRUCT)
1834 {
1835 /* Look for a match through the fields of an anonymous
1836 union, or anonymous struct. C++ provides anonymous
1837 unions.
1838
1839 In the GNU Chill (now deleted from GDB)
1840 implementation of variant record types, each
1841 <alternative field> has an (anonymous) union type,
1842 each member of the union represents a <variant
1843 alternative>. Each <variant alternative> is
1844 represented as a struct, with a member for each
1845 <variant field>. */
1846
1847 struct value *v = NULL;
1848 int new_offset = offset;
1849
1850 /* This is pretty gross. In G++, the offset in an
1851 anonymous union is relative to the beginning of the
1852 enclosing struct. In the GNU Chill (now deleted
1853 from GDB) implementation of variant records, the
1854 bitpos is zero in an anonymous union field, so we
1855 have to add the offset of the union here. */
1856 if (TYPE_CODE (field_type) == TYPE_CODE_STRUCT
1857 || (TYPE_NFIELDS (field_type) > 0
1858 && TYPE_FIELD_BITPOS (field_type, 0) == 0))
1859 new_offset += TYPE_FIELD_BITPOS (type, i) / 8;
1860
1861 do_search_struct_field (name, arg1, new_offset,
1862 field_type,
1863 looking_for_baseclass, &v,
1864 last_boffset,
1865 outermost_type);
1866 if (v)
1867 {
1868 *result_ptr = v;
1869 return;
1870 }
1871 }
1872 }
1873 }
1874
1875 for (i = 0; i < nbases; i++)
1876 {
1877 struct value *v = NULL;
1878 struct type *basetype = check_typedef (TYPE_BASECLASS (type, i));
1879 /* If we are looking for baseclasses, this is what we get when
1880 we hit them. But it could happen that the base part's member
1881 name is not yet filled in. */
1882 int found_baseclass = (looking_for_baseclass
1883 && TYPE_BASECLASS_NAME (type, i) != NULL
1884 && (strcmp_iw (name,
1885 TYPE_BASECLASS_NAME (type,
1886 i)) == 0));
1887 int boffset = value_embedded_offset (arg1) + offset;
1888
1889 if (BASETYPE_VIA_VIRTUAL (type, i))
1890 {
1891 struct value *v2;
1892
1893 boffset = baseclass_offset (type, i,
1894 value_contents_for_printing (arg1),
1895 value_embedded_offset (arg1) + offset,
1896 value_address (arg1),
1897 arg1);
1898
1899 /* The virtual base class pointer might have been clobbered
1900 by the user program. Make sure that it still points to a
1901 valid memory location. */
1902
1903 boffset += value_embedded_offset (arg1) + offset;
1904 if (boffset < 0
1905 || boffset >= TYPE_LENGTH (value_enclosing_type (arg1)))
1906 {
1907 CORE_ADDR base_addr;
1908
1909 base_addr = value_address (arg1) + boffset;
1910 v2 = value_at_lazy (basetype, base_addr);
1911 if (target_read_memory (base_addr,
1912 value_contents_raw (v2),
1913 TYPE_LENGTH (value_type (v2))) != 0)
1914 error (_("virtual baseclass botch"));
1915 }
1916 else
1917 {
1918 v2 = value_copy (arg1);
1919 deprecated_set_value_type (v2, basetype);
1920 set_value_embedded_offset (v2, boffset);
1921 }
1922
1923 if (found_baseclass)
1924 v = v2;
1925 else
1926 {
1927 do_search_struct_field (name, v2, 0,
1928 TYPE_BASECLASS (type, i),
1929 looking_for_baseclass,
1930 result_ptr, last_boffset,
1931 outermost_type);
1932 }
1933 }
1934 else if (found_baseclass)
1935 v = value_primitive_field (arg1, offset, i, type);
1936 else
1937 {
1938 do_search_struct_field (name, arg1,
1939 offset + TYPE_BASECLASS_BITPOS (type,
1940 i) / 8,
1941 basetype, looking_for_baseclass,
1942 result_ptr, last_boffset,
1943 outermost_type);
1944 }
1945
1946 update_search_result (result_ptr, v, last_boffset,
1947 boffset, name, outermost_type);
1948 }
1949 }
1950
1951 /* Helper function used by value_struct_elt to recurse through
1952 baseclasses. Look for a field NAME in ARG1. Search in it assuming
1953 it has (class) type TYPE. If found, return value, else return NULL.
1954
1955 If LOOKING_FOR_BASECLASS, then instead of looking for struct
1956 fields, look for a baseclass named NAME. */
1957
1958 static struct value *
1959 search_struct_field (const char *name, struct value *arg1,
1960 struct type *type, int looking_for_baseclass)
1961 {
1962 struct value *result = NULL;
1963 int boffset = 0;
1964
1965 do_search_struct_field (name, arg1, 0, type, looking_for_baseclass,
1966 &result, &boffset, type);
1967 return result;
1968 }
1969
1970 /* Helper function used by value_struct_elt to recurse through
1971 baseclasses. Look for a field NAME in ARG1. Adjust the address of
1972 ARG1 by OFFSET bytes, and search in it assuming it has (class) type
1973 TYPE.
1974
1975 If found, return value, else if name matched and args not return
1976 (value) -1, else return NULL. */
1977
1978 static struct value *
1979 search_struct_method (const char *name, struct value **arg1p,
1980 struct value **args, int offset,
1981 int *static_memfuncp, struct type *type)
1982 {
1983 int i;
1984 struct value *v;
1985 int name_matched = 0;
1986 char dem_opname[64];
1987
1988 CHECK_TYPEDEF (type);
1989 for (i = TYPE_NFN_FIELDS (type) - 1; i >= 0; i--)
1990 {
1991 const char *t_field_name = TYPE_FN_FIELDLIST_NAME (type, i);
1992
1993 /* FIXME! May need to check for ARM demangling here. */
1994 if (startswith (t_field_name, "__") ||
1995 startswith (t_field_name, "op") ||
1996 startswith (t_field_name, "type"))
1997 {
1998 if (cplus_demangle_opname (t_field_name, dem_opname, DMGL_ANSI))
1999 t_field_name = dem_opname;
2000 else if (cplus_demangle_opname (t_field_name, dem_opname, 0))
2001 t_field_name = dem_opname;
2002 }
2003 if (t_field_name && (strcmp_iw (t_field_name, name) == 0))
2004 {
2005 int j = TYPE_FN_FIELDLIST_LENGTH (type, i) - 1;
2006 struct fn_field *f = TYPE_FN_FIELDLIST1 (type, i);
2007
2008 name_matched = 1;
2009 check_stub_method_group (type, i);
2010 if (j > 0 && args == 0)
2011 error (_("cannot resolve overloaded method "
2012 "`%s': no arguments supplied"), name);
2013 else if (j == 0 && args == 0)
2014 {
2015 v = value_fn_field (arg1p, f, j, type, offset);
2016 if (v != NULL)
2017 return v;
2018 }
2019 else
2020 while (j >= 0)
2021 {
2022 if (!typecmp (TYPE_FN_FIELD_STATIC_P (f, j),
2023 TYPE_VARARGS (TYPE_FN_FIELD_TYPE (f, j)),
2024 TYPE_NFIELDS (TYPE_FN_FIELD_TYPE (f, j)),
2025 TYPE_FN_FIELD_ARGS (f, j), args))
2026 {
2027 if (TYPE_FN_FIELD_VIRTUAL_P (f, j))
2028 return value_virtual_fn_field (arg1p, f, j,
2029 type, offset);
2030 if (TYPE_FN_FIELD_STATIC_P (f, j)
2031 && static_memfuncp)
2032 *static_memfuncp = 1;
2033 v = value_fn_field (arg1p, f, j, type, offset);
2034 if (v != NULL)
2035 return v;
2036 }
2037 j--;
2038 }
2039 }
2040 }
2041
2042 for (i = TYPE_N_BASECLASSES (type) - 1; i >= 0; i--)
2043 {
2044 int base_offset;
2045 int this_offset;
2046
2047 if (BASETYPE_VIA_VIRTUAL (type, i))
2048 {
2049 struct type *baseclass = check_typedef (TYPE_BASECLASS (type, i));
2050 struct value *base_val;
2051 const gdb_byte *base_valaddr;
2052
2053 /* The virtual base class pointer might have been
2054 clobbered by the user program. Make sure that it
2055 still points to a valid memory location. */
2056
2057 if (offset < 0 || offset >= TYPE_LENGTH (type))
2058 {
2059 gdb_byte *tmp;
2060 struct cleanup *back_to;
2061 CORE_ADDR address;
2062
2063 tmp = xmalloc (TYPE_LENGTH (baseclass));
2064 back_to = make_cleanup (xfree, tmp);
2065 address = value_address (*arg1p);
2066
2067 if (target_read_memory (address + offset,
2068 tmp, TYPE_LENGTH (baseclass)) != 0)
2069 error (_("virtual baseclass botch"));
2070
2071 base_val = value_from_contents_and_address (baseclass,
2072 tmp,
2073 address + offset);
2074 base_valaddr = value_contents_for_printing (base_val);
2075 this_offset = 0;
2076 do_cleanups (back_to);
2077 }
2078 else
2079 {
2080 base_val = *arg1p;
2081 base_valaddr = value_contents_for_printing (*arg1p);
2082 this_offset = offset;
2083 }
2084
2085 base_offset = baseclass_offset (type, i, base_valaddr,
2086 this_offset, value_address (base_val),
2087 base_val);
2088 }
2089 else
2090 {
2091 base_offset = TYPE_BASECLASS_BITPOS (type, i) / 8;
2092 }
2093 v = search_struct_method (name, arg1p, args, base_offset + offset,
2094 static_memfuncp, TYPE_BASECLASS (type, i));
2095 if (v == (struct value *) - 1)
2096 {
2097 name_matched = 1;
2098 }
2099 else if (v)
2100 {
2101 /* FIXME-bothner: Why is this commented out? Why is it here? */
2102 /* *arg1p = arg1_tmp; */
2103 return v;
2104 }
2105 }
2106 if (name_matched)
2107 return (struct value *) - 1;
2108 else
2109 return NULL;
2110 }
2111
2112 /* Given *ARGP, a value of type (pointer to a)* structure/union,
2113 extract the component named NAME from the ultimate target
2114 structure/union and return it as a value with its appropriate type.
2115 ERR is used in the error message if *ARGP's type is wrong.
2116
2117 C++: ARGS is a list of argument types to aid in the selection of
2118 an appropriate method. Also, handle derived types.
2119
2120 STATIC_MEMFUNCP, if non-NULL, points to a caller-supplied location
2121 where the truthvalue of whether the function that was resolved was
2122 a static member function or not is stored.
2123
2124 ERR is an error message to be printed in case the field is not
2125 found. */
2126
2127 struct value *
2128 value_struct_elt (struct value **argp, struct value **args,
2129 const char *name, int *static_memfuncp, const char *err)
2130 {
2131 struct type *t;
2132 struct value *v;
2133
2134 *argp = coerce_array (*argp);
2135
2136 t = check_typedef (value_type (*argp));
2137
2138 /* Follow pointers until we get to a non-pointer. */
2139
2140 while (TYPE_CODE (t) == TYPE_CODE_PTR || TYPE_CODE (t) == TYPE_CODE_REF)
2141 {
2142 *argp = value_ind (*argp);
2143 /* Don't coerce fn pointer to fn and then back again! */
2144 if (TYPE_CODE (check_typedef (value_type (*argp))) != TYPE_CODE_FUNC)
2145 *argp = coerce_array (*argp);
2146 t = check_typedef (value_type (*argp));
2147 }
2148
2149 if (TYPE_CODE (t) != TYPE_CODE_STRUCT
2150 && TYPE_CODE (t) != TYPE_CODE_UNION)
2151 error (_("Attempt to extract a component of a value that is not a %s."),
2152 err);
2153
2154 /* Assume it's not, unless we see that it is. */
2155 if (static_memfuncp)
2156 *static_memfuncp = 0;
2157
2158 if (!args)
2159 {
2160 /* if there are no arguments ...do this... */
2161
2162 /* Try as a field first, because if we succeed, there is less
2163 work to be done. */
2164 v = search_struct_field (name, *argp, t, 0);
2165 if (v)
2166 return v;
2167
2168 /* C++: If it was not found as a data field, then try to
2169 return it as a pointer to a method. */
2170 v = search_struct_method (name, argp, args, 0,
2171 static_memfuncp, t);
2172
2173 if (v == (struct value *) - 1)
2174 error (_("Cannot take address of method %s."), name);
2175 else if (v == 0)
2176 {
2177 if (TYPE_NFN_FIELDS (t))
2178 error (_("There is no member or method named %s."), name);
2179 else
2180 error (_("There is no member named %s."), name);
2181 }
2182 return v;
2183 }
2184
2185 v = search_struct_method (name, argp, args, 0,
2186 static_memfuncp, t);
2187
2188 if (v == (struct value *) - 1)
2189 {
2190 error (_("One of the arguments you tried to pass to %s could not "
2191 "be converted to what the function wants."), name);
2192 }
2193 else if (v == 0)
2194 {
2195 /* See if user tried to invoke data as function. If so, hand it
2196 back. If it's not callable (i.e., a pointer to function),
2197 gdb should give an error. */
2198 v = search_struct_field (name, *argp, t, 0);
2199 /* If we found an ordinary field, then it is not a method call.
2200 So, treat it as if it were a static member function. */
2201 if (v && static_memfuncp)
2202 *static_memfuncp = 1;
2203 }
2204
2205 if (!v)
2206 throw_error (NOT_FOUND_ERROR,
2207 _("Structure has no component named %s."), name);
2208 return v;
2209 }
2210
2211 /* Given *ARGP, a value of type structure or union, or a pointer/reference
2212 to a structure or union, extract and return its component (field) of
2213 type FTYPE at the specified BITPOS.
2214 Throw an exception on error. */
2215
2216 struct value *
2217 value_struct_elt_bitpos (struct value **argp, int bitpos, struct type *ftype,
2218 const char *err)
2219 {
2220 struct type *t;
2221 struct value *v;
2222 int i;
2223 int nbases;
2224
2225 *argp = coerce_array (*argp);
2226
2227 t = check_typedef (value_type (*argp));
2228
2229 while (TYPE_CODE (t) == TYPE_CODE_PTR || TYPE_CODE (t) == TYPE_CODE_REF)
2230 {
2231 *argp = value_ind (*argp);
2232 if (TYPE_CODE (check_typedef (value_type (*argp))) != TYPE_CODE_FUNC)
2233 *argp = coerce_array (*argp);
2234 t = check_typedef (value_type (*argp));
2235 }
2236
2237 if (TYPE_CODE (t) != TYPE_CODE_STRUCT
2238 && TYPE_CODE (t) != TYPE_CODE_UNION)
2239 error (_("Attempt to extract a component of a value that is not a %s."),
2240 err);
2241
2242 for (i = TYPE_N_BASECLASSES (t); i < TYPE_NFIELDS (t); i++)
2243 {
2244 if (!field_is_static (&TYPE_FIELD (t, i))
2245 && bitpos == TYPE_FIELD_BITPOS (t, i)
2246 && types_equal (ftype, TYPE_FIELD_TYPE (t, i)))
2247 return value_primitive_field (*argp, 0, i, t);
2248 }
2249
2250 error (_("No field with matching bitpos and type."));
2251
2252 /* Never hit. */
2253 return NULL;
2254 }
2255
2256 /* Search through the methods of an object (and its bases) to find a
2257 specified method. Return the pointer to the fn_field list FN_LIST of
2258 overloaded instances defined in the source language. If available
2259 and matching, a vector of matching xmethods defined in extension
2260 languages are also returned in XM_WORKER_VEC
2261
2262 Helper function for value_find_oload_list.
2263 ARGP is a pointer to a pointer to a value (the object).
2264 METHOD is a string containing the method name.
2265 OFFSET is the offset within the value.
2266 TYPE is the assumed type of the object.
2267 FN_LIST is the pointer to matching overloaded instances defined in
2268 source language. Since this is a recursive function, *FN_LIST
2269 should be set to NULL when calling this function.
2270 NUM_FNS is the number of overloaded instances. *NUM_FNS should be set to
2271 0 when calling this function.
2272 XM_WORKER_VEC is the vector of matching xmethod workers. *XM_WORKER_VEC
2273 should also be set to NULL when calling this function.
2274 BASETYPE is set to the actual type of the subobject where the
2275 method is found.
2276 BOFFSET is the offset of the base subobject where the method is found. */
2277
2278 static void
2279 find_method_list (struct value **argp, const char *method,
2280 int offset, struct type *type,
2281 struct fn_field **fn_list, int *num_fns,
2282 VEC (xmethod_worker_ptr) **xm_worker_vec,
2283 struct type **basetype, int *boffset)
2284 {
2285 int i;
2286 struct fn_field *f = NULL;
2287 VEC (xmethod_worker_ptr) *worker_vec = NULL, *new_vec = NULL;
2288
2289 gdb_assert (fn_list != NULL && xm_worker_vec != NULL);
2290 CHECK_TYPEDEF (type);
2291
2292 /* First check in object itself.
2293 This function is called recursively to search through base classes.
2294 If there is a source method match found at some stage, then we need not
2295 look for source methods in consequent recursive calls. */
2296 if ((*fn_list) == NULL)
2297 {
2298 for (i = TYPE_NFN_FIELDS (type) - 1; i >= 0; i--)
2299 {
2300 /* pai: FIXME What about operators and type conversions? */
2301 const char *fn_field_name = TYPE_FN_FIELDLIST_NAME (type, i);
2302
2303 if (fn_field_name && (strcmp_iw (fn_field_name, method) == 0))
2304 {
2305 int len = TYPE_FN_FIELDLIST_LENGTH (type, i);
2306 f = TYPE_FN_FIELDLIST1 (type, i);
2307 *fn_list = f;
2308
2309 *num_fns = len;
2310 *basetype = type;
2311 *boffset = offset;
2312
2313 /* Resolve any stub methods. */
2314 check_stub_method_group (type, i);
2315
2316 break;
2317 }
2318 }
2319 }
2320
2321 /* Unlike source methods, xmethods can be accumulated over successive
2322 recursive calls. In other words, an xmethod named 'm' in a class
2323 will not hide an xmethod named 'm' in its base class(es). We want
2324 it to be this way because xmethods are after all convenience functions
2325 and hence there is no point restricting them with something like method
2326 hiding. Moreover, if hiding is done for xmethods as well, then we will
2327 have to provide a mechanism to un-hide (like the 'using' construct). */
2328 worker_vec = get_matching_xmethod_workers (type, method);
2329 new_vec = VEC_merge (xmethod_worker_ptr, *xm_worker_vec, worker_vec);
2330
2331 VEC_free (xmethod_worker_ptr, *xm_worker_vec);
2332 VEC_free (xmethod_worker_ptr, worker_vec);
2333 *xm_worker_vec = new_vec;
2334
2335 /* If source methods are not found in current class, look for them in the
2336 base classes. We also have to go through the base classes to gather
2337 extension methods. */
2338 for (i = TYPE_N_BASECLASSES (type) - 1; i >= 0; i--)
2339 {
2340 int base_offset;
2341
2342 if (BASETYPE_VIA_VIRTUAL (type, i))
2343 {
2344 base_offset = baseclass_offset (type, i,
2345 value_contents_for_printing (*argp),
2346 value_offset (*argp) + offset,
2347 value_address (*argp), *argp);
2348 }
2349 else /* Non-virtual base, simply use bit position from debug
2350 info. */
2351 {
2352 base_offset = TYPE_BASECLASS_BITPOS (type, i) / 8;
2353 }
2354
2355 find_method_list (argp, method, base_offset + offset,
2356 TYPE_BASECLASS (type, i), fn_list, num_fns,
2357 xm_worker_vec, basetype, boffset);
2358 }
2359 }
2360
2361 /* Return the list of overloaded methods of a specified name. The methods
2362 could be those GDB finds in the binary, or xmethod. Methods found in
2363 the binary are returned in FN_LIST, and xmethods are returned in
2364 XM_WORKER_VEC.
2365
2366 ARGP is a pointer to a pointer to a value (the object).
2367 METHOD is the method name.
2368 OFFSET is the offset within the value contents.
2369 FN_LIST is the pointer to matching overloaded instances defined in
2370 source language.
2371 NUM_FNS is the number of overloaded instances.
2372 XM_WORKER_VEC is the vector of matching xmethod workers defined in
2373 extension languages.
2374 BASETYPE is set to the type of the base subobject that defines the
2375 method.
2376 BOFFSET is the offset of the base subobject which defines the method. */
2377
2378 static void
2379 value_find_oload_method_list (struct value **argp, const char *method,
2380 int offset, struct fn_field **fn_list,
2381 int *num_fns,
2382 VEC (xmethod_worker_ptr) **xm_worker_vec,
2383 struct type **basetype, int *boffset)
2384 {
2385 struct type *t;
2386
2387 t = check_typedef (value_type (*argp));
2388
2389 /* Code snarfed from value_struct_elt. */
2390 while (TYPE_CODE (t) == TYPE_CODE_PTR || TYPE_CODE (t) == TYPE_CODE_REF)
2391 {
2392 *argp = value_ind (*argp);
2393 /* Don't coerce fn pointer to fn and then back again! */
2394 if (TYPE_CODE (check_typedef (value_type (*argp))) != TYPE_CODE_FUNC)
2395 *argp = coerce_array (*argp);
2396 t = check_typedef (value_type (*argp));
2397 }
2398
2399 if (TYPE_CODE (t) != TYPE_CODE_STRUCT
2400 && TYPE_CODE (t) != TYPE_CODE_UNION)
2401 error (_("Attempt to extract a component of a "
2402 "value that is not a struct or union"));
2403
2404 gdb_assert (fn_list != NULL && xm_worker_vec != NULL);
2405
2406 /* Clear the lists. */
2407 *fn_list = NULL;
2408 *num_fns = 0;
2409 *xm_worker_vec = NULL;
2410
2411 find_method_list (argp, method, 0, t, fn_list, num_fns, xm_worker_vec,
2412 basetype, boffset);
2413 }
2414
2415 /* Given an array of arguments (ARGS) (which includes an
2416 entry for "this" in the case of C++ methods), the number of
2417 arguments NARGS, the NAME of a function, and whether it's a method or
2418 not (METHOD), find the best function that matches on the argument types
2419 according to the overload resolution rules.
2420
2421 METHOD can be one of three values:
2422 NON_METHOD for non-member functions.
2423 METHOD: for member functions.
2424 BOTH: used for overload resolution of operators where the
2425 candidates are expected to be either member or non member
2426 functions. In this case the first argument ARGTYPES
2427 (representing 'this') is expected to be a reference to the
2428 target object, and will be dereferenced when attempting the
2429 non-member search.
2430
2431 In the case of class methods, the parameter OBJ is an object value
2432 in which to search for overloaded methods.
2433
2434 In the case of non-method functions, the parameter FSYM is a symbol
2435 corresponding to one of the overloaded functions.
2436
2437 Return value is an integer: 0 -> good match, 10 -> debugger applied
2438 non-standard coercions, 100 -> incompatible.
2439
2440 If a method is being searched for, VALP will hold the value.
2441 If a non-method is being searched for, SYMP will hold the symbol
2442 for it.
2443
2444 If a method is being searched for, and it is a static method,
2445 then STATICP will point to a non-zero value.
2446
2447 If NO_ADL argument dependent lookup is disabled. This is used to prevent
2448 ADL overload candidates when performing overload resolution for a fully
2449 qualified name.
2450
2451 If NOSIDE is EVAL_AVOID_SIDE_EFFECTS, then OBJP's memory cannot be
2452 read while picking the best overload match (it may be all zeroes and thus
2453 not have a vtable pointer), in which case skip virtual function lookup.
2454 This is ok as typically EVAL_AVOID_SIDE_EFFECTS is only used to determine
2455 the result type.
2456
2457 Note: This function does *not* check the value of
2458 overload_resolution. Caller must check it to see whether overload
2459 resolution is permitted. */
2460
2461 int
2462 find_overload_match (struct value **args, int nargs,
2463 const char *name, enum oload_search_type method,
2464 struct value **objp, struct symbol *fsym,
2465 struct value **valp, struct symbol **symp,
2466 int *staticp, const int no_adl,
2467 const enum noside noside)
2468 {
2469 struct value *obj = (objp ? *objp : NULL);
2470 struct type *obj_type = obj ? value_type (obj) : NULL;
2471 /* Index of best overloaded function. */
2472 int func_oload_champ = -1;
2473 int method_oload_champ = -1;
2474 int src_method_oload_champ = -1;
2475 int ext_method_oload_champ = -1;
2476 int src_and_ext_equal = 0;
2477
2478 /* The measure for the current best match. */
2479 struct badness_vector *method_badness = NULL;
2480 struct badness_vector *func_badness = NULL;
2481 struct badness_vector *ext_method_badness = NULL;
2482 struct badness_vector *src_method_badness = NULL;
2483
2484 struct value *temp = obj;
2485 /* For methods, the list of overloaded methods. */
2486 struct fn_field *fns_ptr = NULL;
2487 /* For non-methods, the list of overloaded function symbols. */
2488 struct symbol **oload_syms = NULL;
2489 /* For xmethods, the VEC of xmethod workers. */
2490 VEC (xmethod_worker_ptr) *xm_worker_vec = NULL;
2491 /* Number of overloaded instances being considered. */
2492 int num_fns = 0;
2493 struct type *basetype = NULL;
2494 int boffset;
2495
2496 struct cleanup *all_cleanups = make_cleanup (null_cleanup, NULL);
2497
2498 const char *obj_type_name = NULL;
2499 const char *func_name = NULL;
2500 enum oload_classification match_quality;
2501 enum oload_classification method_match_quality = INCOMPATIBLE;
2502 enum oload_classification src_method_match_quality = INCOMPATIBLE;
2503 enum oload_classification ext_method_match_quality = INCOMPATIBLE;
2504 enum oload_classification func_match_quality = INCOMPATIBLE;
2505
2506 /* Get the list of overloaded methods or functions. */
2507 if (method == METHOD || method == BOTH)
2508 {
2509 gdb_assert (obj);
2510
2511 /* OBJ may be a pointer value rather than the object itself. */
2512 obj = coerce_ref (obj);
2513 while (TYPE_CODE (check_typedef (value_type (obj))) == TYPE_CODE_PTR)
2514 obj = coerce_ref (value_ind (obj));
2515 obj_type_name = TYPE_NAME (value_type (obj));
2516
2517 /* First check whether this is a data member, e.g. a pointer to
2518 a function. */
2519 if (TYPE_CODE (check_typedef (value_type (obj))) == TYPE_CODE_STRUCT)
2520 {
2521 *valp = search_struct_field (name, obj,
2522 check_typedef (value_type (obj)), 0);
2523 if (*valp)
2524 {
2525 *staticp = 1;
2526 do_cleanups (all_cleanups);
2527 return 0;
2528 }
2529 }
2530
2531 /* Retrieve the list of methods with the name NAME. */
2532 value_find_oload_method_list (&temp, name, 0, &fns_ptr, &num_fns,
2533 &xm_worker_vec, &basetype, &boffset);
2534 /* If this is a method only search, and no methods were found
2535 the search has faild. */
2536 if (method == METHOD && (!fns_ptr || !num_fns) && !xm_worker_vec)
2537 error (_("Couldn't find method %s%s%s"),
2538 obj_type_name,
2539 (obj_type_name && *obj_type_name) ? "::" : "",
2540 name);
2541 /* If we are dealing with stub method types, they should have
2542 been resolved by find_method_list via
2543 value_find_oload_method_list above. */
2544 if (fns_ptr)
2545 {
2546 gdb_assert (TYPE_SELF_TYPE (fns_ptr[0].type) != NULL);
2547
2548 src_method_oload_champ = find_oload_champ (args, nargs,
2549 num_fns, fns_ptr, NULL,
2550 NULL, &src_method_badness);
2551
2552 src_method_match_quality = classify_oload_match
2553 (src_method_badness, nargs,
2554 oload_method_static_p (fns_ptr, src_method_oload_champ));
2555
2556 make_cleanup (xfree, src_method_badness);
2557 }
2558
2559 if (VEC_length (xmethod_worker_ptr, xm_worker_vec) > 0)
2560 {
2561 ext_method_oload_champ = find_oload_champ (args, nargs,
2562 0, NULL, xm_worker_vec,
2563 NULL, &ext_method_badness);
2564 ext_method_match_quality = classify_oload_match (ext_method_badness,
2565 nargs, 0);
2566 make_cleanup (xfree, ext_method_badness);
2567 make_cleanup (free_xmethod_worker_vec, xm_worker_vec);
2568 }
2569
2570 if (src_method_oload_champ >= 0 && ext_method_oload_champ >= 0)
2571 {
2572 switch (compare_badness (ext_method_badness, src_method_badness))
2573 {
2574 case 0: /* Src method and xmethod are equally good. */
2575 src_and_ext_equal = 1;
2576 /* If src method and xmethod are equally good, then
2577 xmethod should be the winner. Hence, fall through to the
2578 case where a xmethod is better than the source
2579 method, except when the xmethod match quality is
2580 non-standard. */
2581 /* FALLTHROUGH */
2582 case 1: /* Src method and ext method are incompatible. */
2583 /* If ext method match is not standard, then let source method
2584 win. Otherwise, fallthrough to let xmethod win. */
2585 if (ext_method_match_quality != STANDARD)
2586 {
2587 method_oload_champ = src_method_oload_champ;
2588 method_badness = src_method_badness;
2589 ext_method_oload_champ = -1;
2590 method_match_quality = src_method_match_quality;
2591 break;
2592 }
2593 /* FALLTHROUGH */
2594 case 2: /* Ext method is champion. */
2595 method_oload_champ = ext_method_oload_champ;
2596 method_badness = ext_method_badness;
2597 src_method_oload_champ = -1;
2598 method_match_quality = ext_method_match_quality;
2599 break;
2600 case 3: /* Src method is champion. */
2601 method_oload_champ = src_method_oload_champ;
2602 method_badness = src_method_badness;
2603 ext_method_oload_champ = -1;
2604 method_match_quality = src_method_match_quality;
2605 break;
2606 default:
2607 gdb_assert_not_reached ("Unexpected overload comparison "
2608 "result");
2609 break;
2610 }
2611 }
2612 else if (src_method_oload_champ >= 0)
2613 {
2614 method_oload_champ = src_method_oload_champ;
2615 method_badness = src_method_badness;
2616 method_match_quality = src_method_match_quality;
2617 }
2618 else if (ext_method_oload_champ >= 0)
2619 {
2620 method_oload_champ = ext_method_oload_champ;
2621 method_badness = ext_method_badness;
2622 method_match_quality = ext_method_match_quality;
2623 }
2624 }
2625
2626 if (method == NON_METHOD || method == BOTH)
2627 {
2628 const char *qualified_name = NULL;
2629
2630 /* If the overload match is being search for both as a method
2631 and non member function, the first argument must now be
2632 dereferenced. */
2633 if (method == BOTH)
2634 args[0] = value_ind (args[0]);
2635
2636 if (fsym)
2637 {
2638 qualified_name = SYMBOL_NATURAL_NAME (fsym);
2639
2640 /* If we have a function with a C++ name, try to extract just
2641 the function part. Do not try this for non-functions (e.g.
2642 function pointers). */
2643 if (qualified_name
2644 && TYPE_CODE (check_typedef (SYMBOL_TYPE (fsym)))
2645 == TYPE_CODE_FUNC)
2646 {
2647 char *temp;
2648
2649 temp = cp_func_name (qualified_name);
2650
2651 /* If cp_func_name did not remove anything, the name of the
2652 symbol did not include scope or argument types - it was
2653 probably a C-style function. */
2654 if (temp)
2655 {
2656 make_cleanup (xfree, temp);
2657 if (strcmp (temp, qualified_name) == 0)
2658 func_name = NULL;
2659 else
2660 func_name = temp;
2661 }
2662 }
2663 }
2664 else
2665 {
2666 func_name = name;
2667 qualified_name = name;
2668 }
2669
2670 /* If there was no C++ name, this must be a C-style function or
2671 not a function at all. Just return the same symbol. Do the
2672 same if cp_func_name fails for some reason. */
2673 if (func_name == NULL)
2674 {
2675 *symp = fsym;
2676 do_cleanups (all_cleanups);
2677 return 0;
2678 }
2679
2680 func_oload_champ = find_oload_champ_namespace (args, nargs,
2681 func_name,
2682 qualified_name,
2683 &oload_syms,
2684 &func_badness,
2685 no_adl);
2686
2687 if (func_oload_champ >= 0)
2688 func_match_quality = classify_oload_match (func_badness, nargs, 0);
2689
2690 make_cleanup (xfree, oload_syms);
2691 make_cleanup (xfree, func_badness);
2692 }
2693
2694 /* Did we find a match ? */
2695 if (method_oload_champ == -1 && func_oload_champ == -1)
2696 throw_error (NOT_FOUND_ERROR,
2697 _("No symbol \"%s\" in current context."),
2698 name);
2699
2700 /* If we have found both a method match and a function
2701 match, find out which one is better, and calculate match
2702 quality. */
2703 if (method_oload_champ >= 0 && func_oload_champ >= 0)
2704 {
2705 switch (compare_badness (func_badness, method_badness))
2706 {
2707 case 0: /* Top two contenders are equally good. */
2708 /* FIXME: GDB does not support the general ambiguous case.
2709 All candidates should be collected and presented the
2710 user. */
2711 error (_("Ambiguous overload resolution"));
2712 break;
2713 case 1: /* Incomparable top contenders. */
2714 /* This is an error incompatible candidates
2715 should not have been proposed. */
2716 error (_("Internal error: incompatible "
2717 "overload candidates proposed"));
2718 break;
2719 case 2: /* Function champion. */
2720 method_oload_champ = -1;
2721 match_quality = func_match_quality;
2722 break;
2723 case 3: /* Method champion. */
2724 func_oload_champ = -1;
2725 match_quality = method_match_quality;
2726 break;
2727 default:
2728 error (_("Internal error: unexpected overload comparison result"));
2729 break;
2730 }
2731 }
2732 else
2733 {
2734 /* We have either a method match or a function match. */
2735 if (method_oload_champ >= 0)
2736 match_quality = method_match_quality;
2737 else
2738 match_quality = func_match_quality;
2739 }
2740
2741 if (match_quality == INCOMPATIBLE)
2742 {
2743 if (method == METHOD)
2744 error (_("Cannot resolve method %s%s%s to any overloaded instance"),
2745 obj_type_name,
2746 (obj_type_name && *obj_type_name) ? "::" : "",
2747 name);
2748 else
2749 error (_("Cannot resolve function %s to any overloaded instance"),
2750 func_name);
2751 }
2752 else if (match_quality == NON_STANDARD)
2753 {
2754 if (method == METHOD)
2755 warning (_("Using non-standard conversion to match "
2756 "method %s%s%s to supplied arguments"),
2757 obj_type_name,
2758 (obj_type_name && *obj_type_name) ? "::" : "",
2759 name);
2760 else
2761 warning (_("Using non-standard conversion to match "
2762 "function %s to supplied arguments"),
2763 func_name);
2764 }
2765
2766 if (staticp != NULL)
2767 *staticp = oload_method_static_p (fns_ptr, method_oload_champ);
2768
2769 if (method_oload_champ >= 0)
2770 {
2771 if (src_method_oload_champ >= 0)
2772 {
2773 if (TYPE_FN_FIELD_VIRTUAL_P (fns_ptr, method_oload_champ)
2774 && noside != EVAL_AVOID_SIDE_EFFECTS)
2775 {
2776 *valp = value_virtual_fn_field (&temp, fns_ptr,
2777 method_oload_champ, basetype,
2778 boffset);
2779 }
2780 else
2781 *valp = value_fn_field (&temp, fns_ptr, method_oload_champ,
2782 basetype, boffset);
2783 }
2784 else
2785 {
2786 *valp = value_of_xmethod (clone_xmethod_worker
2787 (VEC_index (xmethod_worker_ptr, xm_worker_vec,
2788 ext_method_oload_champ)));
2789 }
2790 }
2791 else
2792 *symp = oload_syms[func_oload_champ];
2793
2794 if (objp)
2795 {
2796 struct type *temp_type = check_typedef (value_type (temp));
2797 struct type *objtype = check_typedef (obj_type);
2798
2799 if (TYPE_CODE (temp_type) != TYPE_CODE_PTR
2800 && (TYPE_CODE (objtype) == TYPE_CODE_PTR
2801 || TYPE_CODE (objtype) == TYPE_CODE_REF))
2802 {
2803 temp = value_addr (temp);
2804 }
2805 *objp = temp;
2806 }
2807
2808 do_cleanups (all_cleanups);
2809
2810 switch (match_quality)
2811 {
2812 case INCOMPATIBLE:
2813 return 100;
2814 case NON_STANDARD:
2815 return 10;
2816 default: /* STANDARD */
2817 return 0;
2818 }
2819 }
2820
2821 /* Find the best overload match, searching for FUNC_NAME in namespaces
2822 contained in QUALIFIED_NAME until it either finds a good match or
2823 runs out of namespaces. It stores the overloaded functions in
2824 *OLOAD_SYMS, and the badness vector in *OLOAD_CHAMP_BV. The
2825 calling function is responsible for freeing *OLOAD_SYMS and
2826 *OLOAD_CHAMP_BV. If NO_ADL, argument dependent lookup is not
2827 performned. */
2828
2829 static int
2830 find_oload_champ_namespace (struct value **args, int nargs,
2831 const char *func_name,
2832 const char *qualified_name,
2833 struct symbol ***oload_syms,
2834 struct badness_vector **oload_champ_bv,
2835 const int no_adl)
2836 {
2837 int oload_champ;
2838
2839 find_oload_champ_namespace_loop (args, nargs,
2840 func_name,
2841 qualified_name, 0,
2842 oload_syms, oload_champ_bv,
2843 &oload_champ,
2844 no_adl);
2845
2846 return oload_champ;
2847 }
2848
2849 /* Helper function for find_oload_champ_namespace; NAMESPACE_LEN is
2850 how deep we've looked for namespaces, and the champ is stored in
2851 OLOAD_CHAMP. The return value is 1 if the champ is a good one, 0
2852 if it isn't. Other arguments are the same as in
2853 find_oload_champ_namespace
2854
2855 It is the caller's responsibility to free *OLOAD_SYMS and
2856 *OLOAD_CHAMP_BV. */
2857
2858 static int
2859 find_oload_champ_namespace_loop (struct value **args, int nargs,
2860 const char *func_name,
2861 const char *qualified_name,
2862 int namespace_len,
2863 struct symbol ***oload_syms,
2864 struct badness_vector **oload_champ_bv,
2865 int *oload_champ,
2866 const int no_adl)
2867 {
2868 int next_namespace_len = namespace_len;
2869 int searched_deeper = 0;
2870 int num_fns = 0;
2871 struct cleanup *old_cleanups;
2872 int new_oload_champ;
2873 struct symbol **new_oload_syms;
2874 struct badness_vector *new_oload_champ_bv;
2875 char *new_namespace;
2876
2877 if (next_namespace_len != 0)
2878 {
2879 gdb_assert (qualified_name[next_namespace_len] == ':');
2880 next_namespace_len += 2;
2881 }
2882 next_namespace_len +=
2883 cp_find_first_component (qualified_name + next_namespace_len);
2884
2885 /* Initialize these to values that can safely be xfree'd. */
2886 *oload_syms = NULL;
2887 *oload_champ_bv = NULL;
2888
2889 /* First, see if we have a deeper namespace we can search in.
2890 If we get a good match there, use it. */
2891
2892 if (qualified_name[next_namespace_len] == ':')
2893 {
2894 searched_deeper = 1;
2895
2896 if (find_oload_champ_namespace_loop (args, nargs,
2897 func_name, qualified_name,
2898 next_namespace_len,
2899 oload_syms, oload_champ_bv,
2900 oload_champ, no_adl))
2901 {
2902 return 1;
2903 }
2904 };
2905
2906 /* If we reach here, either we're in the deepest namespace or we
2907 didn't find a good match in a deeper namespace. But, in the
2908 latter case, we still have a bad match in a deeper namespace;
2909 note that we might not find any match at all in the current
2910 namespace. (There's always a match in the deepest namespace,
2911 because this overload mechanism only gets called if there's a
2912 function symbol to start off with.) */
2913
2914 old_cleanups = make_cleanup (xfree, *oload_syms);
2915 make_cleanup (xfree, *oload_champ_bv);
2916 new_namespace = alloca (namespace_len + 1);
2917 strncpy (new_namespace, qualified_name, namespace_len);
2918 new_namespace[namespace_len] = '\0';
2919 new_oload_syms = make_symbol_overload_list (func_name,
2920 new_namespace);
2921
2922 /* If we have reached the deepest level perform argument
2923 determined lookup. */
2924 if (!searched_deeper && !no_adl)
2925 {
2926 int ix;
2927 struct type **arg_types;
2928
2929 /* Prepare list of argument types for overload resolution. */
2930 arg_types = (struct type **)
2931 alloca (nargs * (sizeof (struct type *)));
2932 for (ix = 0; ix < nargs; ix++)
2933 arg_types[ix] = value_type (args[ix]);
2934 make_symbol_overload_list_adl (arg_types, nargs, func_name);
2935 }
2936
2937 while (new_oload_syms[num_fns])
2938 ++num_fns;
2939
2940 new_oload_champ = find_oload_champ (args, nargs, num_fns,
2941 NULL, NULL, new_oload_syms,
2942 &new_oload_champ_bv);
2943
2944 /* Case 1: We found a good match. Free earlier matches (if any),
2945 and return it. Case 2: We didn't find a good match, but we're
2946 not the deepest function. Then go with the bad match that the
2947 deeper function found. Case 3: We found a bad match, and we're
2948 the deepest function. Then return what we found, even though
2949 it's a bad match. */
2950
2951 if (new_oload_champ != -1
2952 && classify_oload_match (new_oload_champ_bv, nargs, 0) == STANDARD)
2953 {
2954 *oload_syms = new_oload_syms;
2955 *oload_champ = new_oload_champ;
2956 *oload_champ_bv = new_oload_champ_bv;
2957 do_cleanups (old_cleanups);
2958 return 1;
2959 }
2960 else if (searched_deeper)
2961 {
2962 xfree (new_oload_syms);
2963 xfree (new_oload_champ_bv);
2964 discard_cleanups (old_cleanups);
2965 return 0;
2966 }
2967 else
2968 {
2969 *oload_syms = new_oload_syms;
2970 *oload_champ = new_oload_champ;
2971 *oload_champ_bv = new_oload_champ_bv;
2972 do_cleanups (old_cleanups);
2973 return 0;
2974 }
2975 }
2976
2977 /* Look for a function to take NARGS args of ARGS. Find
2978 the best match from among the overloaded methods or functions
2979 given by FNS_PTR or OLOAD_SYMS or XM_WORKER_VEC, respectively.
2980 One, and only one of FNS_PTR, OLOAD_SYMS and XM_WORKER_VEC can be
2981 non-NULL.
2982
2983 If XM_WORKER_VEC is NULL, then the length of the arrays FNS_PTR
2984 or OLOAD_SYMS (whichever is non-NULL) is specified in NUM_FNS.
2985
2986 Return the index of the best match; store an indication of the
2987 quality of the match in OLOAD_CHAMP_BV.
2988
2989 It is the caller's responsibility to free *OLOAD_CHAMP_BV. */
2990
2991 static int
2992 find_oload_champ (struct value **args, int nargs,
2993 int num_fns, struct fn_field *fns_ptr,
2994 VEC (xmethod_worker_ptr) *xm_worker_vec,
2995 struct symbol **oload_syms,
2996 struct badness_vector **oload_champ_bv)
2997 {
2998 int ix;
2999 int fn_count;
3000 int xm_worker_vec_n = VEC_length (xmethod_worker_ptr, xm_worker_vec);
3001 /* A measure of how good an overloaded instance is. */
3002 struct badness_vector *bv;
3003 /* Index of best overloaded function. */
3004 int oload_champ = -1;
3005 /* Current ambiguity state for overload resolution. */
3006 int oload_ambiguous = 0;
3007 /* 0 => no ambiguity, 1 => two good funcs, 2 => incomparable funcs. */
3008
3009 /* A champion can be found among methods alone, or among functions
3010 alone, or in xmethods alone, but not in more than one of these
3011 groups. */
3012 gdb_assert ((fns_ptr != NULL) + (oload_syms != NULL) + (xm_worker_vec != NULL)
3013 == 1);
3014
3015 *oload_champ_bv = NULL;
3016
3017 fn_count = (xm_worker_vec != NULL
3018 ? VEC_length (xmethod_worker_ptr, xm_worker_vec)
3019 : num_fns);
3020 /* Consider each candidate in turn. */
3021 for (ix = 0; ix < fn_count; ix++)
3022 {
3023 int jj;
3024 int static_offset = 0;
3025 int nparms;
3026 struct type **parm_types;
3027 struct xmethod_worker *worker = NULL;
3028
3029 if (xm_worker_vec != NULL)
3030 {
3031 worker = VEC_index (xmethod_worker_ptr, xm_worker_vec, ix);
3032 parm_types = get_xmethod_arg_types (worker, &nparms);
3033 }
3034 else
3035 {
3036 if (fns_ptr != NULL)
3037 {
3038 nparms = TYPE_NFIELDS (TYPE_FN_FIELD_TYPE (fns_ptr, ix));
3039 static_offset = oload_method_static_p (fns_ptr, ix);
3040 }
3041 else
3042 nparms = TYPE_NFIELDS (SYMBOL_TYPE (oload_syms[ix]));
3043
3044 parm_types = (struct type **)
3045 xmalloc (nparms * (sizeof (struct type *)));
3046 for (jj = 0; jj < nparms; jj++)
3047 parm_types[jj] = (fns_ptr != NULL
3048 ? (TYPE_FN_FIELD_ARGS (fns_ptr, ix)[jj].type)
3049 : TYPE_FIELD_TYPE (SYMBOL_TYPE (oload_syms[ix]),
3050 jj));
3051 }
3052
3053 /* Compare parameter types to supplied argument types. Skip
3054 THIS for static methods. */
3055 bv = rank_function (parm_types, nparms,
3056 args + static_offset,
3057 nargs - static_offset);
3058
3059 if (!*oload_champ_bv)
3060 {
3061 *oload_champ_bv = bv;
3062 oload_champ = 0;
3063 }
3064 else /* See whether current candidate is better or worse than
3065 previous best. */
3066 switch (compare_badness (bv, *oload_champ_bv))
3067 {
3068 case 0: /* Top two contenders are equally good. */
3069 oload_ambiguous = 1;
3070 break;
3071 case 1: /* Incomparable top contenders. */
3072 oload_ambiguous = 2;
3073 break;
3074 case 2: /* New champion, record details. */
3075 *oload_champ_bv = bv;
3076 oload_ambiguous = 0;
3077 oload_champ = ix;
3078 break;
3079 case 3:
3080 default:
3081 break;
3082 }
3083 xfree (parm_types);
3084 if (overload_debug)
3085 {
3086 if (fns_ptr != NULL)
3087 fprintf_filtered (gdb_stderr,
3088 "Overloaded method instance %s, # of parms %d\n",
3089 fns_ptr[ix].physname, nparms);
3090 else if (xm_worker_vec != NULL)
3091 fprintf_filtered (gdb_stderr,
3092 "Xmethod worker, # of parms %d\n",
3093 nparms);
3094 else
3095 fprintf_filtered (gdb_stderr,
3096 "Overloaded function instance "
3097 "%s # of parms %d\n",
3098 SYMBOL_DEMANGLED_NAME (oload_syms[ix]),
3099 nparms);
3100 for (jj = 0; jj < nargs - static_offset; jj++)
3101 fprintf_filtered (gdb_stderr,
3102 "...Badness @ %d : %d\n",
3103 jj, bv->rank[jj].rank);
3104 fprintf_filtered (gdb_stderr, "Overload resolution "
3105 "champion is %d, ambiguous? %d\n",
3106 oload_champ, oload_ambiguous);
3107 }
3108 }
3109
3110 return oload_champ;
3111 }
3112
3113 /* Return 1 if we're looking at a static method, 0 if we're looking at
3114 a non-static method or a function that isn't a method. */
3115
3116 static int
3117 oload_method_static_p (struct fn_field *fns_ptr, int index)
3118 {
3119 if (fns_ptr && index >= 0 && TYPE_FN_FIELD_STATIC_P (fns_ptr, index))
3120 return 1;
3121 else
3122 return 0;
3123 }
3124
3125 /* Check how good an overload match OLOAD_CHAMP_BV represents. */
3126
3127 static enum oload_classification
3128 classify_oload_match (struct badness_vector *oload_champ_bv,
3129 int nargs,
3130 int static_offset)
3131 {
3132 int ix;
3133 enum oload_classification worst = STANDARD;
3134
3135 for (ix = 1; ix <= nargs - static_offset; ix++)
3136 {
3137 /* If this conversion is as bad as INCOMPATIBLE_TYPE_BADNESS
3138 or worse return INCOMPATIBLE. */
3139 if (compare_ranks (oload_champ_bv->rank[ix],
3140 INCOMPATIBLE_TYPE_BADNESS) <= 0)
3141 return INCOMPATIBLE; /* Truly mismatched types. */
3142 /* Otherwise If this conversion is as bad as
3143 NS_POINTER_CONVERSION_BADNESS or worse return NON_STANDARD. */
3144 else if (compare_ranks (oload_champ_bv->rank[ix],
3145 NS_POINTER_CONVERSION_BADNESS) <= 0)
3146 worst = NON_STANDARD; /* Non-standard type conversions
3147 needed. */
3148 }
3149
3150 /* If no INCOMPATIBLE classification was found, return the worst one
3151 that was found (if any). */
3152 return worst;
3153 }
3154
3155 /* C++: return 1 is NAME is a legitimate name for the destructor of
3156 type TYPE. If TYPE does not have a destructor, or if NAME is
3157 inappropriate for TYPE, an error is signaled. Parameter TYPE should not yet
3158 have CHECK_TYPEDEF applied, this function will apply it itself. */
3159
3160 int
3161 destructor_name_p (const char *name, struct type *type)
3162 {
3163 if (name[0] == '~')
3164 {
3165 const char *dname = type_name_no_tag_or_error (type);
3166 const char *cp = strchr (dname, '<');
3167 unsigned int len;
3168
3169 /* Do not compare the template part for template classes. */
3170 if (cp == NULL)
3171 len = strlen (dname);
3172 else
3173 len = cp - dname;
3174 if (strlen (name + 1) != len || strncmp (dname, name + 1, len) != 0)
3175 error (_("name of destructor must equal name of class"));
3176 else
3177 return 1;
3178 }
3179 return 0;
3180 }
3181
3182 /* Find an enum constant named NAME in TYPE. TYPE must be an "enum
3183 class". If the name is found, return a value representing it;
3184 otherwise throw an exception. */
3185
3186 static struct value *
3187 enum_constant_from_type (struct type *type, const char *name)
3188 {
3189 int i;
3190 int name_len = strlen (name);
3191
3192 gdb_assert (TYPE_CODE (type) == TYPE_CODE_ENUM
3193 && TYPE_DECLARED_CLASS (type));
3194
3195 for (i = TYPE_N_BASECLASSES (type); i < TYPE_NFIELDS (type); ++i)
3196 {
3197 const char *fname = TYPE_FIELD_NAME (type, i);
3198 int len;
3199
3200 if (TYPE_FIELD_LOC_KIND (type, i) != FIELD_LOC_KIND_ENUMVAL
3201 || fname == NULL)
3202 continue;
3203
3204 /* Look for the trailing "::NAME", since enum class constant
3205 names are qualified here. */
3206 len = strlen (fname);
3207 if (len + 2 >= name_len
3208 && fname[len - name_len - 2] == ':'
3209 && fname[len - name_len - 1] == ':'
3210 && strcmp (&fname[len - name_len], name) == 0)
3211 return value_from_longest (type, TYPE_FIELD_ENUMVAL (type, i));
3212 }
3213
3214 error (_("no constant named \"%s\" in enum \"%s\""),
3215 name, TYPE_TAG_NAME (type));
3216 }
3217
3218 /* C++: Given an aggregate type CURTYPE, and a member name NAME,
3219 return the appropriate member (or the address of the member, if
3220 WANT_ADDRESS). This function is used to resolve user expressions
3221 of the form "DOMAIN::NAME". For more details on what happens, see
3222 the comment before value_struct_elt_for_reference. */
3223
3224 struct value *
3225 value_aggregate_elt (struct type *curtype, const char *name,
3226 struct type *expect_type, int want_address,
3227 enum noside noside)
3228 {
3229 switch (TYPE_CODE (curtype))
3230 {
3231 case TYPE_CODE_STRUCT:
3232 case TYPE_CODE_UNION:
3233 return value_struct_elt_for_reference (curtype, 0, curtype,
3234 name, expect_type,
3235 want_address, noside);
3236 case TYPE_CODE_NAMESPACE:
3237 return value_namespace_elt (curtype, name,
3238 want_address, noside);
3239
3240 case TYPE_CODE_ENUM:
3241 return enum_constant_from_type (curtype, name);
3242
3243 default:
3244 internal_error (__FILE__, __LINE__,
3245 _("non-aggregate type in value_aggregate_elt"));
3246 }
3247 }
3248
3249 /* Compares the two method/function types T1 and T2 for "equality"
3250 with respect to the methods' parameters. If the types of the
3251 two parameter lists are the same, returns 1; 0 otherwise. This
3252 comparison may ignore any artificial parameters in T1 if
3253 SKIP_ARTIFICIAL is non-zero. This function will ALWAYS skip
3254 the first artificial parameter in T1, assumed to be a 'this' pointer.
3255
3256 The type T2 is expected to have come from make_params (in eval.c). */
3257
3258 static int
3259 compare_parameters (struct type *t1, struct type *t2, int skip_artificial)
3260 {
3261 int start = 0;
3262
3263 if (TYPE_NFIELDS (t1) > 0 && TYPE_FIELD_ARTIFICIAL (t1, 0))
3264 ++start;
3265
3266 /* If skipping artificial fields, find the first real field
3267 in T1. */
3268 if (skip_artificial)
3269 {
3270 while (start < TYPE_NFIELDS (t1)
3271 && TYPE_FIELD_ARTIFICIAL (t1, start))
3272 ++start;
3273 }
3274
3275 /* Now compare parameters. */
3276
3277 /* Special case: a method taking void. T1 will contain no
3278 non-artificial fields, and T2 will contain TYPE_CODE_VOID. */
3279 if ((TYPE_NFIELDS (t1) - start) == 0 && TYPE_NFIELDS (t2) == 1
3280 && TYPE_CODE (TYPE_FIELD_TYPE (t2, 0)) == TYPE_CODE_VOID)
3281 return 1;
3282
3283 if ((TYPE_NFIELDS (t1) - start) == TYPE_NFIELDS (t2))
3284 {
3285 int i;
3286
3287 for (i = 0; i < TYPE_NFIELDS (t2); ++i)
3288 {
3289 if (compare_ranks (rank_one_type (TYPE_FIELD_TYPE (t1, start + i),
3290 TYPE_FIELD_TYPE (t2, i), NULL),
3291 EXACT_MATCH_BADNESS) != 0)
3292 return 0;
3293 }
3294
3295 return 1;
3296 }
3297
3298 return 0;
3299 }
3300
3301 /* C++: Given an aggregate type CURTYPE, and a member name NAME,
3302 return the address of this member as a "pointer to member" type.
3303 If INTYPE is non-null, then it will be the type of the member we
3304 are looking for. This will help us resolve "pointers to member
3305 functions". This function is used to resolve user expressions of
3306 the form "DOMAIN::NAME". */
3307
3308 static struct value *
3309 value_struct_elt_for_reference (struct type *domain, int offset,
3310 struct type *curtype, const char *name,
3311 struct type *intype,
3312 int want_address,
3313 enum noside noside)
3314 {
3315 struct type *t = curtype;
3316 int i;
3317 struct value *v, *result;
3318
3319 if (TYPE_CODE (t) != TYPE_CODE_STRUCT
3320 && TYPE_CODE (t) != TYPE_CODE_UNION)
3321 error (_("Internal error: non-aggregate type "
3322 "to value_struct_elt_for_reference"));
3323
3324 for (i = TYPE_NFIELDS (t) - 1; i >= TYPE_N_BASECLASSES (t); i--)
3325 {
3326 const char *t_field_name = TYPE_FIELD_NAME (t, i);
3327
3328 if (t_field_name && strcmp (t_field_name, name) == 0)
3329 {
3330 if (field_is_static (&TYPE_FIELD (t, i)))
3331 {
3332 v = value_static_field (t, i);
3333 if (want_address)
3334 v = value_addr (v);
3335 return v;
3336 }
3337 if (TYPE_FIELD_PACKED (t, i))
3338 error (_("pointers to bitfield members not allowed"));
3339
3340 if (want_address)
3341 return value_from_longest
3342 (lookup_memberptr_type (TYPE_FIELD_TYPE (t, i), domain),
3343 offset + (LONGEST) (TYPE_FIELD_BITPOS (t, i) >> 3));
3344 else if (noside != EVAL_NORMAL)
3345 return allocate_value (TYPE_FIELD_TYPE (t, i));
3346 else
3347 {
3348 /* Try to evaluate NAME as a qualified name with implicit
3349 this pointer. In this case, attempt to return the
3350 equivalent to `this->*(&TYPE::NAME)'. */
3351 v = value_of_this_silent (current_language);
3352 if (v != NULL)
3353 {
3354 struct value *ptr;
3355 long mem_offset;
3356 struct type *type, *tmp;
3357
3358 ptr = value_aggregate_elt (domain, name, NULL, 1, noside);
3359 type = check_typedef (value_type (ptr));
3360 gdb_assert (type != NULL
3361 && TYPE_CODE (type) == TYPE_CODE_MEMBERPTR);
3362 tmp = lookup_pointer_type (TYPE_SELF_TYPE (type));
3363 v = value_cast_pointers (tmp, v, 1);
3364 mem_offset = value_as_long (ptr);
3365 tmp = lookup_pointer_type (TYPE_TARGET_TYPE (type));
3366 result = value_from_pointer (tmp,
3367 value_as_long (v) + mem_offset);
3368 return value_ind (result);
3369 }
3370
3371 error (_("Cannot reference non-static field \"%s\""), name);
3372 }
3373 }
3374 }
3375
3376 /* C++: If it was not found as a data field, then try to return it
3377 as a pointer to a method. */
3378
3379 /* Perform all necessary dereferencing. */
3380 while (intype && TYPE_CODE (intype) == TYPE_CODE_PTR)
3381 intype = TYPE_TARGET_TYPE (intype);
3382
3383 for (i = TYPE_NFN_FIELDS (t) - 1; i >= 0; --i)
3384 {
3385 const char *t_field_name = TYPE_FN_FIELDLIST_NAME (t, i);
3386 char dem_opname[64];
3387
3388 if (startswith (t_field_name, "__")
3389 || startswith (t_field_name, "op")
3390 || startswith (t_field_name, "type"))
3391 {
3392 if (cplus_demangle_opname (t_field_name,
3393 dem_opname, DMGL_ANSI))
3394 t_field_name = dem_opname;
3395 else if (cplus_demangle_opname (t_field_name,
3396 dem_opname, 0))
3397 t_field_name = dem_opname;
3398 }
3399 if (t_field_name && strcmp (t_field_name, name) == 0)
3400 {
3401 int j;
3402 int len = TYPE_FN_FIELDLIST_LENGTH (t, i);
3403 struct fn_field *f = TYPE_FN_FIELDLIST1 (t, i);
3404
3405 check_stub_method_group (t, i);
3406
3407 if (intype)
3408 {
3409 for (j = 0; j < len; ++j)
3410 {
3411 if (compare_parameters (TYPE_FN_FIELD_TYPE (f, j), intype, 0)
3412 || compare_parameters (TYPE_FN_FIELD_TYPE (f, j),
3413 intype, 1))
3414 break;
3415 }
3416
3417 if (j == len)
3418 error (_("no member function matches "
3419 "that type instantiation"));
3420 }
3421 else
3422 {
3423 int ii;
3424
3425 j = -1;
3426 for (ii = 0; ii < len; ++ii)
3427 {
3428 /* Skip artificial methods. This is necessary if,
3429 for example, the user wants to "print
3430 subclass::subclass" with only one user-defined
3431 constructor. There is no ambiguity in this case.
3432 We are careful here to allow artificial methods
3433 if they are the unique result. */
3434 if (TYPE_FN_FIELD_ARTIFICIAL (f, ii))
3435 {
3436 if (j == -1)
3437 j = ii;
3438 continue;
3439 }
3440
3441 /* Desired method is ambiguous if more than one
3442 method is defined. */
3443 if (j != -1 && !TYPE_FN_FIELD_ARTIFICIAL (f, j))
3444 error (_("non-unique member `%s' requires "
3445 "type instantiation"), name);
3446
3447 j = ii;
3448 }
3449
3450 if (j == -1)
3451 error (_("no matching member function"));
3452 }
3453
3454 if (TYPE_FN_FIELD_STATIC_P (f, j))
3455 {
3456 struct symbol *s =
3457 lookup_symbol (TYPE_FN_FIELD_PHYSNAME (f, j),
3458 0, VAR_DOMAIN, 0);
3459
3460 if (s == NULL)
3461 return NULL;
3462
3463 if (want_address)
3464 return value_addr (read_var_value (s, 0));
3465 else
3466 return read_var_value (s, 0);
3467 }
3468
3469 if (TYPE_FN_FIELD_VIRTUAL_P (f, j))
3470 {
3471 if (want_address)
3472 {
3473 result = allocate_value
3474 (lookup_methodptr_type (TYPE_FN_FIELD_TYPE (f, j)));
3475 cplus_make_method_ptr (value_type (result),
3476 value_contents_writeable (result),
3477 TYPE_FN_FIELD_VOFFSET (f, j), 1);
3478 }
3479 else if (noside == EVAL_AVOID_SIDE_EFFECTS)
3480 return allocate_value (TYPE_FN_FIELD_TYPE (f, j));
3481 else
3482 error (_("Cannot reference virtual member function \"%s\""),
3483 name);
3484 }
3485 else
3486 {
3487 struct symbol *s =
3488 lookup_symbol (TYPE_FN_FIELD_PHYSNAME (f, j),
3489 0, VAR_DOMAIN, 0);
3490
3491 if (s == NULL)
3492 return NULL;
3493
3494 v = read_var_value (s, 0);
3495 if (!want_address)
3496 result = v;
3497 else
3498 {
3499 result = allocate_value (lookup_methodptr_type (TYPE_FN_FIELD_TYPE (f, j)));
3500 cplus_make_method_ptr (value_type (result),
3501 value_contents_writeable (result),
3502 value_address (v), 0);
3503 }
3504 }
3505 return result;
3506 }
3507 }
3508 for (i = TYPE_N_BASECLASSES (t) - 1; i >= 0; i--)
3509 {
3510 struct value *v;
3511 int base_offset;
3512
3513 if (BASETYPE_VIA_VIRTUAL (t, i))
3514 base_offset = 0;
3515 else
3516 base_offset = TYPE_BASECLASS_BITPOS (t, i) / 8;
3517 v = value_struct_elt_for_reference (domain,
3518 offset + base_offset,
3519 TYPE_BASECLASS (t, i),
3520 name, intype,
3521 want_address, noside);
3522 if (v)
3523 return v;
3524 }
3525
3526 /* As a last chance, pretend that CURTYPE is a namespace, and look
3527 it up that way; this (frequently) works for types nested inside
3528 classes. */
3529
3530 return value_maybe_namespace_elt (curtype, name,
3531 want_address, noside);
3532 }
3533
3534 /* C++: Return the member NAME of the namespace given by the type
3535 CURTYPE. */
3536
3537 static struct value *
3538 value_namespace_elt (const struct type *curtype,
3539 const char *name, int want_address,
3540 enum noside noside)
3541 {
3542 struct value *retval = value_maybe_namespace_elt (curtype, name,
3543 want_address,
3544 noside);
3545
3546 if (retval == NULL)
3547 error (_("No symbol \"%s\" in namespace \"%s\"."),
3548 name, TYPE_TAG_NAME (curtype));
3549
3550 return retval;
3551 }
3552
3553 /* A helper function used by value_namespace_elt and
3554 value_struct_elt_for_reference. It looks up NAME inside the
3555 context CURTYPE; this works if CURTYPE is a namespace or if CURTYPE
3556 is a class and NAME refers to a type in CURTYPE itself (as opposed
3557 to, say, some base class of CURTYPE). */
3558
3559 static struct value *
3560 value_maybe_namespace_elt (const struct type *curtype,
3561 const char *name, int want_address,
3562 enum noside noside)
3563 {
3564 const char *namespace_name = TYPE_TAG_NAME (curtype);
3565 struct symbol *sym;
3566 struct value *result;
3567
3568 sym = cp_lookup_symbol_namespace (namespace_name, name,
3569 get_selected_block (0), VAR_DOMAIN);
3570
3571 if (sym == NULL)
3572 return NULL;
3573 else if ((noside == EVAL_AVOID_SIDE_EFFECTS)
3574 && (SYMBOL_CLASS (sym) == LOC_TYPEDEF))
3575 result = allocate_value (SYMBOL_TYPE (sym));
3576 else
3577 result = value_of_variable (sym, get_selected_block (0));
3578
3579 if (want_address)
3580 result = value_addr (result);
3581
3582 return result;
3583 }
3584
3585 /* Given a pointer or a reference value V, find its real (RTTI) type.
3586
3587 Other parameters FULL, TOP, USING_ENC as with value_rtti_type()
3588 and refer to the values computed for the object pointed to. */
3589
3590 struct type *
3591 value_rtti_indirect_type (struct value *v, int *full,
3592 int *top, int *using_enc)
3593 {
3594 struct value *target = NULL;
3595 struct type *type, *real_type, *target_type;
3596
3597 type = value_type (v);
3598 type = check_typedef (type);
3599 if (TYPE_CODE (type) == TYPE_CODE_REF)
3600 target = coerce_ref (v);
3601 else if (TYPE_CODE (type) == TYPE_CODE_PTR)
3602 {
3603
3604 TRY
3605 {
3606 target = value_ind (v);
3607 }
3608 CATCH (except, RETURN_MASK_ERROR)
3609 {
3610 if (except.error == MEMORY_ERROR)
3611 {
3612 /* value_ind threw a memory error. The pointer is NULL or
3613 contains an uninitialized value: we can't determine any
3614 type. */
3615 return NULL;
3616 }
3617 throw_exception (except);
3618 }
3619 END_CATCH
3620 }
3621 else
3622 return NULL;
3623
3624 real_type = value_rtti_type (target, full, top, using_enc);
3625
3626 if (real_type)
3627 {
3628 /* Copy qualifiers to the referenced object. */
3629 target_type = value_type (target);
3630 real_type = make_cv_type (TYPE_CONST (target_type),
3631 TYPE_VOLATILE (target_type), real_type, NULL);
3632 if (TYPE_CODE (type) == TYPE_CODE_REF)
3633 real_type = lookup_reference_type (real_type);
3634 else if (TYPE_CODE (type) == TYPE_CODE_PTR)
3635 real_type = lookup_pointer_type (real_type);
3636 else
3637 internal_error (__FILE__, __LINE__, _("Unexpected value type."));
3638
3639 /* Copy qualifiers to the pointer/reference. */
3640 real_type = make_cv_type (TYPE_CONST (type), TYPE_VOLATILE (type),
3641 real_type, NULL);
3642 }
3643
3644 return real_type;
3645 }
3646
3647 /* Given a value pointed to by ARGP, check its real run-time type, and
3648 if that is different from the enclosing type, create a new value
3649 using the real run-time type as the enclosing type (and of the same
3650 type as ARGP) and return it, with the embedded offset adjusted to
3651 be the correct offset to the enclosed object. RTYPE is the type,
3652 and XFULL, XTOP, and XUSING_ENC are the other parameters, computed
3653 by value_rtti_type(). If these are available, they can be supplied
3654 and a second call to value_rtti_type() is avoided. (Pass RTYPE ==
3655 NULL if they're not available. */
3656
3657 struct value *
3658 value_full_object (struct value *argp,
3659 struct type *rtype,
3660 int xfull, int xtop,
3661 int xusing_enc)
3662 {
3663 struct type *real_type;
3664 int full = 0;
3665 int top = -1;
3666 int using_enc = 0;
3667 struct value *new_val;
3668
3669 if (rtype)
3670 {
3671 real_type = rtype;
3672 full = xfull;
3673 top = xtop;
3674 using_enc = xusing_enc;
3675 }
3676 else
3677 real_type = value_rtti_type (argp, &full, &top, &using_enc);
3678
3679 /* If no RTTI data, or if object is already complete, do nothing. */
3680 if (!real_type || real_type == value_enclosing_type (argp))
3681 return argp;
3682
3683 /* In a destructor we might see a real type that is a superclass of
3684 the object's type. In this case it is better to leave the object
3685 as-is. */
3686 if (full
3687 && TYPE_LENGTH (real_type) < TYPE_LENGTH (value_enclosing_type (argp)))
3688 return argp;
3689
3690 /* If we have the full object, but for some reason the enclosing
3691 type is wrong, set it. */
3692 /* pai: FIXME -- sounds iffy */
3693 if (full)
3694 {
3695 argp = value_copy (argp);
3696 set_value_enclosing_type (argp, real_type);
3697 return argp;
3698 }
3699
3700 /* Check if object is in memory. */
3701 if (VALUE_LVAL (argp) != lval_memory)
3702 {
3703 warning (_("Couldn't retrieve complete object of RTTI "
3704 "type %s; object may be in register(s)."),
3705 TYPE_NAME (real_type));
3706
3707 return argp;
3708 }
3709
3710 /* All other cases -- retrieve the complete object. */
3711 /* Go back by the computed top_offset from the beginning of the
3712 object, adjusting for the embedded offset of argp if that's what
3713 value_rtti_type used for its computation. */
3714 new_val = value_at_lazy (real_type, value_address (argp) - top +
3715 (using_enc ? 0 : value_embedded_offset (argp)));
3716 deprecated_set_value_type (new_val, value_type (argp));
3717 set_value_embedded_offset (new_val, (using_enc
3718 ? top + value_embedded_offset (argp)
3719 : top));
3720 return new_val;
3721 }
3722
3723
3724 /* Return the value of the local variable, if one exists. Throw error
3725 otherwise, such as if the request is made in an inappropriate context. */
3726
3727 struct value *
3728 value_of_this (const struct language_defn *lang)
3729 {
3730 struct symbol *sym;
3731 const struct block *b;
3732 struct frame_info *frame;
3733
3734 if (!lang->la_name_of_this)
3735 error (_("no `this' in current language"));
3736
3737 frame = get_selected_frame (_("no frame selected"));
3738
3739 b = get_frame_block (frame, NULL);
3740
3741 sym = lookup_language_this (lang, b);
3742 if (sym == NULL)
3743 error (_("current stack frame does not contain a variable named `%s'"),
3744 lang->la_name_of_this);
3745
3746 return read_var_value (sym, frame);
3747 }
3748
3749 /* Return the value of the local variable, if one exists. Return NULL
3750 otherwise. Never throw error. */
3751
3752 struct value *
3753 value_of_this_silent (const struct language_defn *lang)
3754 {
3755 struct value *ret = NULL;
3756
3757 TRY
3758 {
3759 ret = value_of_this (lang);
3760 }
3761 CATCH (except, RETURN_MASK_ERROR)
3762 {
3763 }
3764 END_CATCH
3765
3766 return ret;
3767 }
3768
3769 /* Create a slice (sub-string, sub-array) of ARRAY, that is LENGTH
3770 elements long, starting at LOWBOUND. The result has the same lower
3771 bound as the original ARRAY. */
3772
3773 struct value *
3774 value_slice (struct value *array, int lowbound, int length)
3775 {
3776 struct type *slice_range_type, *slice_type, *range_type;
3777 LONGEST lowerbound, upperbound;
3778 struct value *slice;
3779 struct type *array_type;
3780
3781 array_type = check_typedef (value_type (array));
3782 if (TYPE_CODE (array_type) != TYPE_CODE_ARRAY
3783 && TYPE_CODE (array_type) != TYPE_CODE_STRING)
3784 error (_("cannot take slice of non-array"));
3785
3786 range_type = TYPE_INDEX_TYPE (array_type);
3787 if (get_discrete_bounds (range_type, &lowerbound, &upperbound) < 0)
3788 error (_("slice from bad array or bitstring"));
3789
3790 if (lowbound < lowerbound || length < 0
3791 || lowbound + length - 1 > upperbound)
3792 error (_("slice out of range"));
3793
3794 /* FIXME-type-allocation: need a way to free this type when we are
3795 done with it. */
3796 slice_range_type = create_static_range_type ((struct type *) NULL,
3797 TYPE_TARGET_TYPE (range_type),
3798 lowbound,
3799 lowbound + length - 1);
3800
3801 {
3802 struct type *element_type = TYPE_TARGET_TYPE (array_type);
3803 LONGEST offset
3804 = (lowbound - lowerbound) * TYPE_LENGTH (check_typedef (element_type));
3805
3806 slice_type = create_array_type ((struct type *) NULL,
3807 element_type,
3808 slice_range_type);
3809 TYPE_CODE (slice_type) = TYPE_CODE (array_type);
3810
3811 if (VALUE_LVAL (array) == lval_memory && value_lazy (array))
3812 slice = allocate_value_lazy (slice_type);
3813 else
3814 {
3815 slice = allocate_value (slice_type);
3816 value_contents_copy (slice, 0, array, offset,
3817 TYPE_LENGTH (slice_type));
3818 }
3819
3820 set_value_component_location (slice, array);
3821 VALUE_FRAME_ID (slice) = VALUE_FRAME_ID (array);
3822 set_value_offset (slice, value_offset (array) + offset);
3823 }
3824
3825 return slice;
3826 }
3827
3828 /* Create a value for a FORTRAN complex number. Currently most of the
3829 time values are coerced to COMPLEX*16 (i.e. a complex number
3830 composed of 2 doubles. This really should be a smarter routine
3831 that figures out precision inteligently as opposed to assuming
3832 doubles. FIXME: fmb */
3833
3834 struct value *
3835 value_literal_complex (struct value *arg1,
3836 struct value *arg2,
3837 struct type *type)
3838 {
3839 struct value *val;
3840 struct type *real_type = TYPE_TARGET_TYPE (type);
3841
3842 val = allocate_value (type);
3843 arg1 = value_cast (real_type, arg1);
3844 arg2 = value_cast (real_type, arg2);
3845
3846 memcpy (value_contents_raw (val),
3847 value_contents (arg1), TYPE_LENGTH (real_type));
3848 memcpy (value_contents_raw (val) + TYPE_LENGTH (real_type),
3849 value_contents (arg2), TYPE_LENGTH (real_type));
3850 return val;
3851 }
3852
3853 /* Cast a value into the appropriate complex data type. */
3854
3855 static struct value *
3856 cast_into_complex (struct type *type, struct value *val)
3857 {
3858 struct type *real_type = TYPE_TARGET_TYPE (type);
3859
3860 if (TYPE_CODE (value_type (val)) == TYPE_CODE_COMPLEX)
3861 {
3862 struct type *val_real_type = TYPE_TARGET_TYPE (value_type (val));
3863 struct value *re_val = allocate_value (val_real_type);
3864 struct value *im_val = allocate_value (val_real_type);
3865
3866 memcpy (value_contents_raw (re_val),
3867 value_contents (val), TYPE_LENGTH (val_real_type));
3868 memcpy (value_contents_raw (im_val),
3869 value_contents (val) + TYPE_LENGTH (val_real_type),
3870 TYPE_LENGTH (val_real_type));
3871
3872 return value_literal_complex (re_val, im_val, type);
3873 }
3874 else if (TYPE_CODE (value_type (val)) == TYPE_CODE_FLT
3875 || TYPE_CODE (value_type (val)) == TYPE_CODE_INT)
3876 return value_literal_complex (val,
3877 value_zero (real_type, not_lval),
3878 type);
3879 else
3880 error (_("cannot cast non-number to complex"));
3881 }
3882
3883 void
3884 _initialize_valops (void)
3885 {
3886 add_setshow_boolean_cmd ("overload-resolution", class_support,
3887 &overload_resolution, _("\
3888 Set overload resolution in evaluating C++ functions."), _("\
3889 Show overload resolution in evaluating C++ functions."),
3890 NULL, NULL,
3891 show_overload_resolution,
3892 &setlist, &showlist);
3893 overload_resolution = 1;
3894 }
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