ab31976041c6e54660cfb290da1c0197e39c266f
[deliverable/binutils-gdb.git] / gdb / valops.c
1 /* Perform non-arithmetic operations on values, for GDB.
2
3 Copyright (C) 1986, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995,
4 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007,
5 2008, 2009, 2010, 2011 Free Software Foundation, Inc.
6
7 This file is part of GDB.
8
9 This program is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 3 of the License, or
12 (at your option) any later version.
13
14 This program is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
18
19 You should have received a copy of the GNU General Public License
20 along with this program. If not, see <http://www.gnu.org/licenses/>. */
21
22 #include "defs.h"
23 #include "symtab.h"
24 #include "gdbtypes.h"
25 #include "value.h"
26 #include "frame.h"
27 #include "inferior.h"
28 #include "gdbcore.h"
29 #include "target.h"
30 #include "demangle.h"
31 #include "language.h"
32 #include "gdbcmd.h"
33 #include "regcache.h"
34 #include "cp-abi.h"
35 #include "block.h"
36 #include "infcall.h"
37 #include "dictionary.h"
38 #include "cp-support.h"
39 #include "dfp.h"
40 #include "user-regs.h"
41 #include "tracepoint.h"
42 #include <errno.h>
43 #include "gdb_string.h"
44 #include "gdb_assert.h"
45 #include "cp-support.h"
46 #include "observer.h"
47 #include "objfiles.h"
48 #include "symtab.h"
49 #include "exceptions.h"
50
51 extern int overload_debug;
52 /* Local functions. */
53
54 static int typecmp (int staticp, int varargs, int nargs,
55 struct field t1[], struct value *t2[]);
56
57 static struct value *search_struct_field (const char *, struct value *,
58 int, struct type *, int);
59
60 static struct value *search_struct_method (const char *, struct value **,
61 struct value **,
62 int, int *, struct type *);
63
64 static int find_oload_champ_namespace (struct type **, int,
65 const char *, const char *,
66 struct symbol ***,
67 struct badness_vector **,
68 const int no_adl);
69
70 static
71 int find_oload_champ_namespace_loop (struct type **, int,
72 const char *, const char *,
73 int, struct symbol ***,
74 struct badness_vector **, int *,
75 const int no_adl);
76
77 static int find_oload_champ (struct type **, int, int, int,
78 struct fn_field *, struct symbol **,
79 struct badness_vector **);
80
81 static int oload_method_static (int, struct fn_field *, int);
82
83 enum oload_classification { STANDARD, NON_STANDARD, INCOMPATIBLE };
84
85 static enum
86 oload_classification classify_oload_match (struct badness_vector *,
87 int, int);
88
89 static struct value *value_struct_elt_for_reference (struct type *,
90 int, struct type *,
91 char *,
92 struct type *,
93 int, enum noside);
94
95 static struct value *value_namespace_elt (const struct type *,
96 char *, int , enum noside);
97
98 static struct value *value_maybe_namespace_elt (const struct type *,
99 char *, int,
100 enum noside);
101
102 static CORE_ADDR allocate_space_in_inferior (int);
103
104 static struct value *cast_into_complex (struct type *, struct value *);
105
106 static struct fn_field *find_method_list (struct value **, const char *,
107 int, struct type *, int *,
108 struct type **, int *);
109
110 void _initialize_valops (void);
111
112 #if 0
113 /* Flag for whether we want to abandon failed expression evals by
114 default. */
115
116 static int auto_abandon = 0;
117 #endif
118
119 int overload_resolution = 0;
120 static void
121 show_overload_resolution (struct ui_file *file, int from_tty,
122 struct cmd_list_element *c,
123 const char *value)
124 {
125 fprintf_filtered (file, _("Overload resolution in evaluating "
126 "C++ functions is %s.\n"),
127 value);
128 }
129
130 /* Find the address of function name NAME in the inferior. If OBJF_P
131 is non-NULL, *OBJF_P will be set to the OBJFILE where the function
132 is defined. */
133
134 struct value *
135 find_function_in_inferior (const char *name, struct objfile **objf_p)
136 {
137 struct symbol *sym;
138
139 sym = lookup_symbol (name, 0, VAR_DOMAIN, 0);
140 if (sym != NULL)
141 {
142 if (SYMBOL_CLASS (sym) != LOC_BLOCK)
143 {
144 error (_("\"%s\" exists in this program but is not a function."),
145 name);
146 }
147
148 if (objf_p)
149 *objf_p = SYMBOL_SYMTAB (sym)->objfile;
150
151 return value_of_variable (sym, NULL);
152 }
153 else
154 {
155 struct minimal_symbol *msymbol =
156 lookup_minimal_symbol (name, NULL, NULL);
157
158 if (msymbol != NULL)
159 {
160 struct objfile *objfile = msymbol_objfile (msymbol);
161 struct gdbarch *gdbarch = get_objfile_arch (objfile);
162
163 struct type *type;
164 CORE_ADDR maddr;
165 type = lookup_pointer_type (builtin_type (gdbarch)->builtin_char);
166 type = lookup_function_type (type);
167 type = lookup_pointer_type (type);
168 maddr = SYMBOL_VALUE_ADDRESS (msymbol);
169
170 if (objf_p)
171 *objf_p = objfile;
172
173 return value_from_pointer (type, maddr);
174 }
175 else
176 {
177 if (!target_has_execution)
178 error (_("evaluation of this expression "
179 "requires the target program to be active"));
180 else
181 error (_("evaluation of this expression requires the "
182 "program to have a function \"%s\"."),
183 name);
184 }
185 }
186 }
187
188 /* Allocate NBYTES of space in the inferior using the inferior's
189 malloc and return a value that is a pointer to the allocated
190 space. */
191
192 struct value *
193 value_allocate_space_in_inferior (int len)
194 {
195 struct objfile *objf;
196 struct value *val = find_function_in_inferior ("malloc", &objf);
197 struct gdbarch *gdbarch = get_objfile_arch (objf);
198 struct value *blocklen;
199
200 blocklen = value_from_longest (builtin_type (gdbarch)->builtin_int, len);
201 val = call_function_by_hand (val, 1, &blocklen);
202 if (value_logical_not (val))
203 {
204 if (!target_has_execution)
205 error (_("No memory available to program now: "
206 "you need to start the target first"));
207 else
208 error (_("No memory available to program: call to malloc failed"));
209 }
210 return val;
211 }
212
213 static CORE_ADDR
214 allocate_space_in_inferior (int len)
215 {
216 return value_as_long (value_allocate_space_in_inferior (len));
217 }
218
219 /* Cast struct value VAL to type TYPE and return as a value.
220 Both type and val must be of TYPE_CODE_STRUCT or TYPE_CODE_UNION
221 for this to work. Typedef to one of the codes is permitted.
222 Returns NULL if the cast is neither an upcast nor a downcast. */
223
224 static struct value *
225 value_cast_structs (struct type *type, struct value *v2)
226 {
227 struct type *t1;
228 struct type *t2;
229 struct value *v;
230
231 gdb_assert (type != NULL && v2 != NULL);
232
233 t1 = check_typedef (type);
234 t2 = check_typedef (value_type (v2));
235
236 /* Check preconditions. */
237 gdb_assert ((TYPE_CODE (t1) == TYPE_CODE_STRUCT
238 || TYPE_CODE (t1) == TYPE_CODE_UNION)
239 && !!"Precondition is that type is of STRUCT or UNION kind.");
240 gdb_assert ((TYPE_CODE (t2) == TYPE_CODE_STRUCT
241 || TYPE_CODE (t2) == TYPE_CODE_UNION)
242 && !!"Precondition is that value is of STRUCT or UNION kind");
243
244 if (TYPE_NAME (t1) != NULL
245 && TYPE_NAME (t2) != NULL
246 && !strcmp (TYPE_NAME (t1), TYPE_NAME (t2)))
247 return NULL;
248
249 /* Upcasting: look in the type of the source to see if it contains the
250 type of the target as a superclass. If so, we'll need to
251 offset the pointer rather than just change its type. */
252 if (TYPE_NAME (t1) != NULL)
253 {
254 v = search_struct_field (type_name_no_tag (t1),
255 v2, 0, t2, 1);
256 if (v)
257 return v;
258 }
259
260 /* Downcasting: look in the type of the target to see if it contains the
261 type of the source as a superclass. If so, we'll need to
262 offset the pointer rather than just change its type. */
263 if (TYPE_NAME (t2) != NULL)
264 {
265 /* Try downcasting using the run-time type of the value. */
266 int full, top, using_enc;
267 struct type *real_type;
268
269 real_type = value_rtti_type (v2, &full, &top, &using_enc);
270 if (real_type)
271 {
272 v = value_full_object (v2, real_type, full, top, using_enc);
273 v = value_at_lazy (real_type, value_address (v));
274
275 /* We might be trying to cast to the outermost enclosing
276 type, in which case search_struct_field won't work. */
277 if (TYPE_NAME (real_type) != NULL
278 && !strcmp (TYPE_NAME (real_type), TYPE_NAME (t1)))
279 return v;
280
281 v = search_struct_field (type_name_no_tag (t2), v, 0, real_type, 1);
282 if (v)
283 return v;
284 }
285
286 /* Try downcasting using information from the destination type
287 T2. This wouldn't work properly for classes with virtual
288 bases, but those were handled above. */
289 v = search_struct_field (type_name_no_tag (t2),
290 value_zero (t1, not_lval), 0, t1, 1);
291 if (v)
292 {
293 /* Downcasting is possible (t1 is superclass of v2). */
294 CORE_ADDR addr2 = value_address (v2);
295
296 addr2 -= value_address (v) + value_embedded_offset (v);
297 return value_at (type, addr2);
298 }
299 }
300
301 return NULL;
302 }
303
304 /* Cast one pointer or reference type to another. Both TYPE and
305 the type of ARG2 should be pointer types, or else both should be
306 reference types. Returns the new pointer or reference. */
307
308 struct value *
309 value_cast_pointers (struct type *type, struct value *arg2)
310 {
311 struct type *type1 = check_typedef (type);
312 struct type *type2 = check_typedef (value_type (arg2));
313 struct type *t1 = check_typedef (TYPE_TARGET_TYPE (type1));
314 struct type *t2 = check_typedef (TYPE_TARGET_TYPE (type2));
315
316 if (TYPE_CODE (t1) == TYPE_CODE_STRUCT
317 && TYPE_CODE (t2) == TYPE_CODE_STRUCT
318 && !value_logical_not (arg2))
319 {
320 struct value *v2;
321
322 if (TYPE_CODE (type2) == TYPE_CODE_REF)
323 v2 = coerce_ref (arg2);
324 else
325 v2 = value_ind (arg2);
326 gdb_assert (TYPE_CODE (check_typedef (value_type (v2)))
327 == TYPE_CODE_STRUCT && !!"Why did coercion fail?");
328 v2 = value_cast_structs (t1, v2);
329 /* At this point we have what we can have, un-dereference if needed. */
330 if (v2)
331 {
332 struct value *v = value_addr (v2);
333
334 deprecated_set_value_type (v, type);
335 return v;
336 }
337 }
338
339 /* No superclass found, just change the pointer type. */
340 arg2 = value_copy (arg2);
341 deprecated_set_value_type (arg2, type);
342 set_value_enclosing_type (arg2, type);
343 set_value_pointed_to_offset (arg2, 0); /* pai: chk_val */
344 return arg2;
345 }
346
347 /* Cast value ARG2 to type TYPE and return as a value.
348 More general than a C cast: accepts any two types of the same length,
349 and if ARG2 is an lvalue it can be cast into anything at all. */
350 /* In C++, casts may change pointer or object representations. */
351
352 struct value *
353 value_cast (struct type *type, struct value *arg2)
354 {
355 enum type_code code1;
356 enum type_code code2;
357 int scalar;
358 struct type *type2;
359
360 int convert_to_boolean = 0;
361
362 if (value_type (arg2) == type)
363 return arg2;
364
365 code1 = TYPE_CODE (check_typedef (type));
366
367 /* Check if we are casting struct reference to struct reference. */
368 if (code1 == TYPE_CODE_REF)
369 {
370 /* We dereference type; then we recurse and finally
371 we generate value of the given reference. Nothing wrong with
372 that. */
373 struct type *t1 = check_typedef (type);
374 struct type *dereftype = check_typedef (TYPE_TARGET_TYPE (t1));
375 struct value *val = value_cast (dereftype, arg2);
376
377 return value_ref (val);
378 }
379
380 code2 = TYPE_CODE (check_typedef (value_type (arg2)));
381
382 if (code2 == TYPE_CODE_REF)
383 /* We deref the value and then do the cast. */
384 return value_cast (type, coerce_ref (arg2));
385
386 CHECK_TYPEDEF (type);
387 code1 = TYPE_CODE (type);
388 arg2 = coerce_ref (arg2);
389 type2 = check_typedef (value_type (arg2));
390
391 /* You can't cast to a reference type. See value_cast_pointers
392 instead. */
393 gdb_assert (code1 != TYPE_CODE_REF);
394
395 /* A cast to an undetermined-length array_type, such as
396 (TYPE [])OBJECT, is treated like a cast to (TYPE [N])OBJECT,
397 where N is sizeof(OBJECT)/sizeof(TYPE). */
398 if (code1 == TYPE_CODE_ARRAY)
399 {
400 struct type *element_type = TYPE_TARGET_TYPE (type);
401 unsigned element_length = TYPE_LENGTH (check_typedef (element_type));
402
403 if (element_length > 0 && TYPE_ARRAY_UPPER_BOUND_IS_UNDEFINED (type))
404 {
405 struct type *range_type = TYPE_INDEX_TYPE (type);
406 int val_length = TYPE_LENGTH (type2);
407 LONGEST low_bound, high_bound, new_length;
408
409 if (get_discrete_bounds (range_type, &low_bound, &high_bound) < 0)
410 low_bound = 0, high_bound = 0;
411 new_length = val_length / element_length;
412 if (val_length % element_length != 0)
413 warning (_("array element type size does not "
414 "divide object size in cast"));
415 /* FIXME-type-allocation: need a way to free this type when
416 we are done with it. */
417 range_type = create_range_type ((struct type *) NULL,
418 TYPE_TARGET_TYPE (range_type),
419 low_bound,
420 new_length + low_bound - 1);
421 deprecated_set_value_type (arg2,
422 create_array_type ((struct type *) NULL,
423 element_type,
424 range_type));
425 return arg2;
426 }
427 }
428
429 if (current_language->c_style_arrays
430 && TYPE_CODE (type2) == TYPE_CODE_ARRAY
431 && !TYPE_VECTOR (type2))
432 arg2 = value_coerce_array (arg2);
433
434 if (TYPE_CODE (type2) == TYPE_CODE_FUNC)
435 arg2 = value_coerce_function (arg2);
436
437 type2 = check_typedef (value_type (arg2));
438 code2 = TYPE_CODE (type2);
439
440 if (code1 == TYPE_CODE_COMPLEX)
441 return cast_into_complex (type, arg2);
442 if (code1 == TYPE_CODE_BOOL)
443 {
444 code1 = TYPE_CODE_INT;
445 convert_to_boolean = 1;
446 }
447 if (code1 == TYPE_CODE_CHAR)
448 code1 = TYPE_CODE_INT;
449 if (code2 == TYPE_CODE_BOOL || code2 == TYPE_CODE_CHAR)
450 code2 = TYPE_CODE_INT;
451
452 scalar = (code2 == TYPE_CODE_INT || code2 == TYPE_CODE_FLT
453 || code2 == TYPE_CODE_DECFLOAT || code2 == TYPE_CODE_ENUM
454 || code2 == TYPE_CODE_RANGE);
455
456 if ((code1 == TYPE_CODE_STRUCT || code1 == TYPE_CODE_UNION)
457 && (code2 == TYPE_CODE_STRUCT || code2 == TYPE_CODE_UNION)
458 && TYPE_NAME (type) != 0)
459 {
460 struct value *v = value_cast_structs (type, arg2);
461
462 if (v)
463 return v;
464 }
465
466 if (code1 == TYPE_CODE_FLT && scalar)
467 return value_from_double (type, value_as_double (arg2));
468 else if (code1 == TYPE_CODE_DECFLOAT && scalar)
469 {
470 enum bfd_endian byte_order = gdbarch_byte_order (get_type_arch (type));
471 int dec_len = TYPE_LENGTH (type);
472 gdb_byte dec[16];
473
474 if (code2 == TYPE_CODE_FLT)
475 decimal_from_floating (arg2, dec, dec_len, byte_order);
476 else if (code2 == TYPE_CODE_DECFLOAT)
477 decimal_convert (value_contents (arg2), TYPE_LENGTH (type2),
478 byte_order, dec, dec_len, byte_order);
479 else
480 /* The only option left is an integral type. */
481 decimal_from_integral (arg2, dec, dec_len, byte_order);
482
483 return value_from_decfloat (type, dec);
484 }
485 else if ((code1 == TYPE_CODE_INT || code1 == TYPE_CODE_ENUM
486 || code1 == TYPE_CODE_RANGE)
487 && (scalar || code2 == TYPE_CODE_PTR
488 || code2 == TYPE_CODE_MEMBERPTR))
489 {
490 LONGEST longest;
491
492 /* When we cast pointers to integers, we mustn't use
493 gdbarch_pointer_to_address to find the address the pointer
494 represents, as value_as_long would. GDB should evaluate
495 expressions just as the compiler would --- and the compiler
496 sees a cast as a simple reinterpretation of the pointer's
497 bits. */
498 if (code2 == TYPE_CODE_PTR)
499 longest = extract_unsigned_integer
500 (value_contents (arg2), TYPE_LENGTH (type2),
501 gdbarch_byte_order (get_type_arch (type2)));
502 else
503 longest = value_as_long (arg2);
504 return value_from_longest (type, convert_to_boolean ?
505 (LONGEST) (longest ? 1 : 0) : longest);
506 }
507 else if (code1 == TYPE_CODE_PTR && (code2 == TYPE_CODE_INT
508 || code2 == TYPE_CODE_ENUM
509 || code2 == TYPE_CODE_RANGE))
510 {
511 /* TYPE_LENGTH (type) is the length of a pointer, but we really
512 want the length of an address! -- we are really dealing with
513 addresses (i.e., gdb representations) not pointers (i.e.,
514 target representations) here.
515
516 This allows things like "print *(int *)0x01000234" to work
517 without printing a misleading message -- which would
518 otherwise occur when dealing with a target having two byte
519 pointers and four byte addresses. */
520
521 int addr_bit = gdbarch_addr_bit (get_type_arch (type2));
522 LONGEST longest = value_as_long (arg2);
523
524 if (addr_bit < sizeof (LONGEST) * HOST_CHAR_BIT)
525 {
526 if (longest >= ((LONGEST) 1 << addr_bit)
527 || longest <= -((LONGEST) 1 << addr_bit))
528 warning (_("value truncated"));
529 }
530 return value_from_longest (type, longest);
531 }
532 else if (code1 == TYPE_CODE_METHODPTR && code2 == TYPE_CODE_INT
533 && value_as_long (arg2) == 0)
534 {
535 struct value *result = allocate_value (type);
536
537 cplus_make_method_ptr (type, value_contents_writeable (result), 0, 0);
538 return result;
539 }
540 else if (code1 == TYPE_CODE_MEMBERPTR && code2 == TYPE_CODE_INT
541 && value_as_long (arg2) == 0)
542 {
543 /* The Itanium C++ ABI represents NULL pointers to members as
544 minus one, instead of biasing the normal case. */
545 return value_from_longest (type, -1);
546 }
547 else if (code1 == TYPE_CODE_ARRAY && TYPE_VECTOR (type) && scalar)
548 {
549 /* Widen the scalar to a vector. */
550 struct type *eltype;
551 struct value *val;
552 LONGEST low_bound, high_bound;
553 int i;
554
555 if (!get_array_bounds (type, &low_bound, &high_bound))
556 error (_("Could not determine the vector bounds"));
557
558 eltype = check_typedef (TYPE_TARGET_TYPE (type));
559 arg2 = value_cast (eltype, arg2);
560 val = allocate_value (type);
561
562 for (i = 0; i < high_bound - low_bound + 1; i++)
563 {
564 /* Duplicate the contents of arg2 into the destination vector. */
565 memcpy (value_contents_writeable (val) + (i * TYPE_LENGTH (eltype)),
566 value_contents_all (arg2), TYPE_LENGTH (eltype));
567 }
568 return val;
569 }
570 else if (TYPE_LENGTH (type) == TYPE_LENGTH (type2))
571 {
572 if (code1 == TYPE_CODE_PTR && code2 == TYPE_CODE_PTR)
573 return value_cast_pointers (type, arg2);
574
575 arg2 = value_copy (arg2);
576 deprecated_set_value_type (arg2, type);
577 set_value_enclosing_type (arg2, type);
578 set_value_pointed_to_offset (arg2, 0); /* pai: chk_val */
579 return arg2;
580 }
581 else if (VALUE_LVAL (arg2) == lval_memory)
582 return value_at_lazy (type, value_address (arg2));
583 else if (code1 == TYPE_CODE_VOID)
584 {
585 return value_zero (type, not_lval);
586 }
587 else
588 {
589 error (_("Invalid cast."));
590 return 0;
591 }
592 }
593
594 /* The C++ reinterpret_cast operator. */
595
596 struct value *
597 value_reinterpret_cast (struct type *type, struct value *arg)
598 {
599 struct value *result;
600 struct type *real_type = check_typedef (type);
601 struct type *arg_type, *dest_type;
602 int is_ref = 0;
603 enum type_code dest_code, arg_code;
604
605 /* Do reference, function, and array conversion. */
606 arg = coerce_array (arg);
607
608 /* Attempt to preserve the type the user asked for. */
609 dest_type = type;
610
611 /* If we are casting to a reference type, transform
612 reinterpret_cast<T&>(V) to *reinterpret_cast<T*>(&V). */
613 if (TYPE_CODE (real_type) == TYPE_CODE_REF)
614 {
615 is_ref = 1;
616 arg = value_addr (arg);
617 dest_type = lookup_pointer_type (TYPE_TARGET_TYPE (dest_type));
618 real_type = lookup_pointer_type (real_type);
619 }
620
621 arg_type = value_type (arg);
622
623 dest_code = TYPE_CODE (real_type);
624 arg_code = TYPE_CODE (arg_type);
625
626 /* We can convert pointer types, or any pointer type to int, or int
627 type to pointer. */
628 if ((dest_code == TYPE_CODE_PTR && arg_code == TYPE_CODE_INT)
629 || (dest_code == TYPE_CODE_INT && arg_code == TYPE_CODE_PTR)
630 || (dest_code == TYPE_CODE_METHODPTR && arg_code == TYPE_CODE_INT)
631 || (dest_code == TYPE_CODE_INT && arg_code == TYPE_CODE_METHODPTR)
632 || (dest_code == TYPE_CODE_MEMBERPTR && arg_code == TYPE_CODE_INT)
633 || (dest_code == TYPE_CODE_INT && arg_code == TYPE_CODE_MEMBERPTR)
634 || (dest_code == arg_code
635 && (dest_code == TYPE_CODE_PTR
636 || dest_code == TYPE_CODE_METHODPTR
637 || dest_code == TYPE_CODE_MEMBERPTR)))
638 result = value_cast (dest_type, arg);
639 else
640 error (_("Invalid reinterpret_cast"));
641
642 if (is_ref)
643 result = value_cast (type, value_ref (value_ind (result)));
644
645 return result;
646 }
647
648 /* A helper for value_dynamic_cast. This implements the first of two
649 runtime checks: we iterate over all the base classes of the value's
650 class which are equal to the desired class; if only one of these
651 holds the value, then it is the answer. */
652
653 static int
654 dynamic_cast_check_1 (struct type *desired_type,
655 const bfd_byte *contents,
656 CORE_ADDR address,
657 struct type *search_type,
658 CORE_ADDR arg_addr,
659 struct type *arg_type,
660 struct value **result)
661 {
662 int i, result_count = 0;
663
664 for (i = 0; i < TYPE_N_BASECLASSES (search_type) && result_count < 2; ++i)
665 {
666 int offset = baseclass_offset (search_type, i, contents, address);
667
668 if (offset == -1)
669 error (_("virtual baseclass botch"));
670 if (class_types_same_p (desired_type, TYPE_BASECLASS (search_type, i)))
671 {
672 if (address + offset >= arg_addr
673 && address + offset < arg_addr + TYPE_LENGTH (arg_type))
674 {
675 ++result_count;
676 if (!*result)
677 *result = value_at_lazy (TYPE_BASECLASS (search_type, i),
678 address + offset);
679 }
680 }
681 else
682 result_count += dynamic_cast_check_1 (desired_type,
683 contents + offset,
684 address + offset,
685 TYPE_BASECLASS (search_type, i),
686 arg_addr,
687 arg_type,
688 result);
689 }
690
691 return result_count;
692 }
693
694 /* A helper for value_dynamic_cast. This implements the second of two
695 runtime checks: we look for a unique public sibling class of the
696 argument's declared class. */
697
698 static int
699 dynamic_cast_check_2 (struct type *desired_type,
700 const bfd_byte *contents,
701 CORE_ADDR address,
702 struct type *search_type,
703 struct value **result)
704 {
705 int i, result_count = 0;
706
707 for (i = 0; i < TYPE_N_BASECLASSES (search_type) && result_count < 2; ++i)
708 {
709 int offset;
710
711 if (! BASETYPE_VIA_PUBLIC (search_type, i))
712 continue;
713
714 offset = baseclass_offset (search_type, i, contents, address);
715 if (offset == -1)
716 error (_("virtual baseclass botch"));
717 if (class_types_same_p (desired_type, TYPE_BASECLASS (search_type, i)))
718 {
719 ++result_count;
720 if (*result == NULL)
721 *result = value_at_lazy (TYPE_BASECLASS (search_type, i),
722 address + offset);
723 }
724 else
725 result_count += dynamic_cast_check_2 (desired_type,
726 contents + offset,
727 address + offset,
728 TYPE_BASECLASS (search_type, i),
729 result);
730 }
731
732 return result_count;
733 }
734
735 /* The C++ dynamic_cast operator. */
736
737 struct value *
738 value_dynamic_cast (struct type *type, struct value *arg)
739 {
740 int full, top, using_enc;
741 struct type *resolved_type = check_typedef (type);
742 struct type *arg_type = check_typedef (value_type (arg));
743 struct type *class_type, *rtti_type;
744 struct value *result, *tem, *original_arg = arg;
745 CORE_ADDR addr;
746 int is_ref = TYPE_CODE (resolved_type) == TYPE_CODE_REF;
747
748 if (TYPE_CODE (resolved_type) != TYPE_CODE_PTR
749 && TYPE_CODE (resolved_type) != TYPE_CODE_REF)
750 error (_("Argument to dynamic_cast must be a pointer or reference type"));
751 if (TYPE_CODE (TYPE_TARGET_TYPE (resolved_type)) != TYPE_CODE_VOID
752 && TYPE_CODE (TYPE_TARGET_TYPE (resolved_type)) != TYPE_CODE_CLASS)
753 error (_("Argument to dynamic_cast must be pointer to class or `void *'"));
754
755 class_type = check_typedef (TYPE_TARGET_TYPE (resolved_type));
756 if (TYPE_CODE (resolved_type) == TYPE_CODE_PTR)
757 {
758 if (TYPE_CODE (arg_type) != TYPE_CODE_PTR
759 && ! (TYPE_CODE (arg_type) == TYPE_CODE_INT
760 && value_as_long (arg) == 0))
761 error (_("Argument to dynamic_cast does not have pointer type"));
762 if (TYPE_CODE (arg_type) == TYPE_CODE_PTR)
763 {
764 arg_type = check_typedef (TYPE_TARGET_TYPE (arg_type));
765 if (TYPE_CODE (arg_type) != TYPE_CODE_CLASS)
766 error (_("Argument to dynamic_cast does "
767 "not have pointer to class type"));
768 }
769
770 /* Handle NULL pointers. */
771 if (value_as_long (arg) == 0)
772 return value_zero (type, not_lval);
773
774 arg = value_ind (arg);
775 }
776 else
777 {
778 if (TYPE_CODE (arg_type) != TYPE_CODE_CLASS)
779 error (_("Argument to dynamic_cast does not have class type"));
780 }
781
782 /* If the classes are the same, just return the argument. */
783 if (class_types_same_p (class_type, arg_type))
784 return value_cast (type, arg);
785
786 /* If the target type is a unique base class of the argument's
787 declared type, just cast it. */
788 if (is_ancestor (class_type, arg_type))
789 {
790 if (is_unique_ancestor (class_type, arg))
791 return value_cast (type, original_arg);
792 error (_("Ambiguous dynamic_cast"));
793 }
794
795 rtti_type = value_rtti_type (arg, &full, &top, &using_enc);
796 if (! rtti_type)
797 error (_("Couldn't determine value's most derived type for dynamic_cast"));
798
799 /* Compute the most derived object's address. */
800 addr = value_address (arg);
801 if (full)
802 {
803 /* Done. */
804 }
805 else if (using_enc)
806 addr += top;
807 else
808 addr += top + value_embedded_offset (arg);
809
810 /* dynamic_cast<void *> means to return a pointer to the
811 most-derived object. */
812 if (TYPE_CODE (resolved_type) == TYPE_CODE_PTR
813 && TYPE_CODE (TYPE_TARGET_TYPE (resolved_type)) == TYPE_CODE_VOID)
814 return value_at_lazy (type, addr);
815
816 tem = value_at (type, addr);
817
818 /* The first dynamic check specified in 5.2.7. */
819 if (is_public_ancestor (arg_type, TYPE_TARGET_TYPE (resolved_type)))
820 {
821 if (class_types_same_p (rtti_type, TYPE_TARGET_TYPE (resolved_type)))
822 return tem;
823 result = NULL;
824 if (dynamic_cast_check_1 (TYPE_TARGET_TYPE (resolved_type),
825 value_contents (tem), value_address (tem),
826 rtti_type, addr,
827 arg_type,
828 &result) == 1)
829 return value_cast (type,
830 is_ref ? value_ref (result) : value_addr (result));
831 }
832
833 /* The second dynamic check specified in 5.2.7. */
834 result = NULL;
835 if (is_public_ancestor (arg_type, rtti_type)
836 && dynamic_cast_check_2 (TYPE_TARGET_TYPE (resolved_type),
837 value_contents (tem), value_address (tem),
838 rtti_type, &result) == 1)
839 return value_cast (type,
840 is_ref ? value_ref (result) : value_addr (result));
841
842 if (TYPE_CODE (resolved_type) == TYPE_CODE_PTR)
843 return value_zero (type, not_lval);
844
845 error (_("dynamic_cast failed"));
846 }
847
848 /* Create a value of type TYPE that is zero, and return it. */
849
850 struct value *
851 value_zero (struct type *type, enum lval_type lv)
852 {
853 struct value *val = allocate_value (type);
854
855 VALUE_LVAL (val) = lv;
856 return val;
857 }
858
859 /* Create a value of numeric type TYPE that is one, and return it. */
860
861 struct value *
862 value_one (struct type *type, enum lval_type lv)
863 {
864 struct type *type1 = check_typedef (type);
865 struct value *val;
866
867 if (TYPE_CODE (type1) == TYPE_CODE_DECFLOAT)
868 {
869 enum bfd_endian byte_order = gdbarch_byte_order (get_type_arch (type));
870 gdb_byte v[16];
871
872 decimal_from_string (v, TYPE_LENGTH (type), byte_order, "1");
873 val = value_from_decfloat (type, v);
874 }
875 else if (TYPE_CODE (type1) == TYPE_CODE_FLT)
876 {
877 val = value_from_double (type, (DOUBLEST) 1);
878 }
879 else if (is_integral_type (type1))
880 {
881 val = value_from_longest (type, (LONGEST) 1);
882 }
883 else if (TYPE_CODE (type1) == TYPE_CODE_ARRAY && TYPE_VECTOR (type1))
884 {
885 struct type *eltype = check_typedef (TYPE_TARGET_TYPE (type1));
886 int i;
887 LONGEST low_bound, high_bound;
888 struct value *tmp;
889
890 if (!get_array_bounds (type1, &low_bound, &high_bound))
891 error (_("Could not determine the vector bounds"));
892
893 val = allocate_value (type);
894 for (i = 0; i < high_bound - low_bound + 1; i++)
895 {
896 tmp = value_one (eltype, lv);
897 memcpy (value_contents_writeable (val) + i * TYPE_LENGTH (eltype),
898 value_contents_all (tmp), TYPE_LENGTH (eltype));
899 }
900 }
901 else
902 {
903 error (_("Not a numeric type."));
904 }
905
906 VALUE_LVAL (val) = lv;
907 return val;
908 }
909
910 /* Helper function for value_at, value_at_lazy, and value_at_lazy_stack. */
911
912 static struct value *
913 get_value_at (struct type *type, CORE_ADDR addr, int lazy)
914 {
915 struct value *val;
916
917 if (TYPE_CODE (check_typedef (type)) == TYPE_CODE_VOID)
918 error (_("Attempt to dereference a generic pointer."));
919
920 val = value_from_contents_and_address (type, NULL, addr);
921
922 if (!lazy)
923 value_fetch_lazy (val);
924
925 return val;
926 }
927
928 /* Return a value with type TYPE located at ADDR.
929
930 Call value_at only if the data needs to be fetched immediately;
931 if we can be 'lazy' and defer the fetch, perhaps indefinately, call
932 value_at_lazy instead. value_at_lazy simply records the address of
933 the data and sets the lazy-evaluation-required flag. The lazy flag
934 is tested in the value_contents macro, which is used if and when
935 the contents are actually required.
936
937 Note: value_at does *NOT* handle embedded offsets; perform such
938 adjustments before or after calling it. */
939
940 struct value *
941 value_at (struct type *type, CORE_ADDR addr)
942 {
943 return get_value_at (type, addr, 0);
944 }
945
946 /* Return a lazy value with type TYPE located at ADDR (cf. value_at). */
947
948 struct value *
949 value_at_lazy (struct type *type, CORE_ADDR addr)
950 {
951 return get_value_at (type, addr, 1);
952 }
953
954 /* Called only from the value_contents and value_contents_all()
955 macros, if the current data for a variable needs to be loaded into
956 value_contents(VAL). Fetches the data from the user's process, and
957 clears the lazy flag to indicate that the data in the buffer is
958 valid.
959
960 If the value is zero-length, we avoid calling read_memory, which
961 would abort. We mark the value as fetched anyway -- all 0 bytes of
962 it.
963
964 This function returns a value because it is used in the
965 value_contents macro as part of an expression, where a void would
966 not work. The value is ignored. */
967
968 int
969 value_fetch_lazy (struct value *val)
970 {
971 gdb_assert (value_lazy (val));
972 allocate_value_contents (val);
973 if (value_bitsize (val))
974 {
975 /* To read a lazy bitfield, read the entire enclosing value. This
976 prevents reading the same block of (possibly volatile) memory once
977 per bitfield. It would be even better to read only the containing
978 word, but we have no way to record that just specific bits of a
979 value have been fetched. */
980 struct type *type = check_typedef (value_type (val));
981 enum bfd_endian byte_order = gdbarch_byte_order (get_type_arch (type));
982 struct value *parent = value_parent (val);
983 LONGEST offset = value_offset (val);
984 LONGEST num;
985 int length = TYPE_LENGTH (type);
986
987 if (!value_bits_valid (val,
988 TARGET_CHAR_BIT * offset + value_bitpos (val),
989 value_bitsize (val)))
990 error (_("value has been optimized out"));
991
992 if (!unpack_value_bits_as_long (value_type (val),
993 value_contents_for_printing (parent),
994 offset,
995 value_bitpos (val),
996 value_bitsize (val), parent, &num))
997 mark_value_bytes_unavailable (val,
998 value_embedded_offset (val),
999 length);
1000 else
1001 store_signed_integer (value_contents_raw (val), length,
1002 byte_order, num);
1003 }
1004 else if (VALUE_LVAL (val) == lval_memory)
1005 {
1006 CORE_ADDR addr = value_address (val);
1007 int length = TYPE_LENGTH (check_typedef (value_enclosing_type (val)));
1008
1009 if (length)
1010 read_value_memory (val, 0, value_stack (val),
1011 addr, value_contents_all_raw (val), length);
1012 }
1013 else if (VALUE_LVAL (val) == lval_register)
1014 {
1015 struct frame_info *frame;
1016 int regnum;
1017 struct type *type = check_typedef (value_type (val));
1018 struct value *new_val = val, *mark = value_mark ();
1019
1020 /* Offsets are not supported here; lazy register values must
1021 refer to the entire register. */
1022 gdb_assert (value_offset (val) == 0);
1023
1024 while (VALUE_LVAL (new_val) == lval_register && value_lazy (new_val))
1025 {
1026 frame = frame_find_by_id (VALUE_FRAME_ID (new_val));
1027 regnum = VALUE_REGNUM (new_val);
1028
1029 gdb_assert (frame != NULL);
1030
1031 /* Convertible register routines are used for multi-register
1032 values and for interpretation in different types
1033 (e.g. float or int from a double register). Lazy
1034 register values should have the register's natural type,
1035 so they do not apply. */
1036 gdb_assert (!gdbarch_convert_register_p (get_frame_arch (frame),
1037 regnum, type));
1038
1039 new_val = get_frame_register_value (frame, regnum);
1040 }
1041
1042 /* If it's still lazy (for instance, a saved register on the
1043 stack), fetch it. */
1044 if (value_lazy (new_val))
1045 value_fetch_lazy (new_val);
1046
1047 /* If the register was not saved, mark it unavailable. */
1048 if (value_optimized_out (new_val))
1049 set_value_optimized_out (val, 1);
1050 else
1051 memcpy (value_contents_raw (val), value_contents (new_val),
1052 TYPE_LENGTH (type));
1053
1054 if (frame_debug)
1055 {
1056 struct gdbarch *gdbarch;
1057 frame = frame_find_by_id (VALUE_FRAME_ID (val));
1058 regnum = VALUE_REGNUM (val);
1059 gdbarch = get_frame_arch (frame);
1060
1061 fprintf_unfiltered (gdb_stdlog,
1062 "{ value_fetch_lazy "
1063 "(frame=%d,regnum=%d(%s),...) ",
1064 frame_relative_level (frame), regnum,
1065 user_reg_map_regnum_to_name (gdbarch, regnum));
1066
1067 fprintf_unfiltered (gdb_stdlog, "->");
1068 if (value_optimized_out (new_val))
1069 fprintf_unfiltered (gdb_stdlog, " optimized out");
1070 else
1071 {
1072 int i;
1073 const gdb_byte *buf = value_contents (new_val);
1074
1075 if (VALUE_LVAL (new_val) == lval_register)
1076 fprintf_unfiltered (gdb_stdlog, " register=%d",
1077 VALUE_REGNUM (new_val));
1078 else if (VALUE_LVAL (new_val) == lval_memory)
1079 fprintf_unfiltered (gdb_stdlog, " address=%s",
1080 paddress (gdbarch,
1081 value_address (new_val)));
1082 else
1083 fprintf_unfiltered (gdb_stdlog, " computed");
1084
1085 fprintf_unfiltered (gdb_stdlog, " bytes=");
1086 fprintf_unfiltered (gdb_stdlog, "[");
1087 for (i = 0; i < register_size (gdbarch, regnum); i++)
1088 fprintf_unfiltered (gdb_stdlog, "%02x", buf[i]);
1089 fprintf_unfiltered (gdb_stdlog, "]");
1090 }
1091
1092 fprintf_unfiltered (gdb_stdlog, " }\n");
1093 }
1094
1095 /* Dispose of the intermediate values. This prevents
1096 watchpoints from trying to watch the saved frame pointer. */
1097 value_free_to_mark (mark);
1098 }
1099 else if (VALUE_LVAL (val) == lval_computed)
1100 value_computed_funcs (val)->read (val);
1101 else if (value_optimized_out (val))
1102 /* Keep it optimized out. */;
1103 else
1104 internal_error (__FILE__, __LINE__, _("Unexpected lazy value type."));
1105
1106 set_value_lazy (val, 0);
1107 return 0;
1108 }
1109
1110 void
1111 read_value_memory (struct value *val, int embedded_offset,
1112 int stack, CORE_ADDR memaddr,
1113 gdb_byte *buffer, size_t length)
1114 {
1115 if (length)
1116 {
1117 VEC(mem_range_s) *available_memory;
1118
1119 if (get_traceframe_number () < 0
1120 || !traceframe_available_memory (&available_memory, memaddr, length))
1121 {
1122 if (stack)
1123 read_stack (memaddr, buffer, length);
1124 else
1125 read_memory (memaddr, buffer, length);
1126 }
1127 else
1128 {
1129 struct target_section_table *table;
1130 struct cleanup *old_chain;
1131 CORE_ADDR unavail;
1132 mem_range_s *r;
1133 int i;
1134
1135 /* Fallback to reading from read-only sections. */
1136 table = target_get_section_table (&exec_ops);
1137 available_memory =
1138 section_table_available_memory (available_memory,
1139 memaddr, length,
1140 table->sections,
1141 table->sections_end);
1142
1143 old_chain = make_cleanup (VEC_cleanup(mem_range_s),
1144 &available_memory);
1145
1146 normalize_mem_ranges (available_memory);
1147
1148 /* Mark which bytes are unavailable, and read those which
1149 are available. */
1150
1151 unavail = memaddr;
1152
1153 for (i = 0;
1154 VEC_iterate (mem_range_s, available_memory, i, r);
1155 i++)
1156 {
1157 if (mem_ranges_overlap (r->start, r->length,
1158 memaddr, length))
1159 {
1160 CORE_ADDR lo1, hi1, lo2, hi2;
1161 CORE_ADDR start, end;
1162
1163 /* Get the intersection window. */
1164 lo1 = memaddr;
1165 hi1 = memaddr + length;
1166 lo2 = r->start;
1167 hi2 = r->start + r->length;
1168 start = max (lo1, lo2);
1169 end = min (hi1, hi2);
1170
1171 gdb_assert (end - memaddr <= length);
1172
1173 if (start > unavail)
1174 mark_value_bytes_unavailable (val,
1175 (embedded_offset
1176 + unavail - memaddr),
1177 start - unavail);
1178 unavail = end;
1179
1180 read_memory (start, buffer + start - memaddr, end - start);
1181 }
1182 }
1183
1184 if (unavail != memaddr + length)
1185 mark_value_bytes_unavailable (val,
1186 embedded_offset + unavail - memaddr,
1187 (memaddr + length) - unavail);
1188
1189 do_cleanups (old_chain);
1190 }
1191 }
1192 }
1193
1194 /* Store the contents of FROMVAL into the location of TOVAL.
1195 Return a new value with the location of TOVAL and contents of FROMVAL. */
1196
1197 struct value *
1198 value_assign (struct value *toval, struct value *fromval)
1199 {
1200 struct type *type;
1201 struct value *val;
1202 struct frame_id old_frame;
1203
1204 if (!deprecated_value_modifiable (toval))
1205 error (_("Left operand of assignment is not a modifiable lvalue."));
1206
1207 toval = coerce_ref (toval);
1208
1209 type = value_type (toval);
1210 if (VALUE_LVAL (toval) != lval_internalvar)
1211 fromval = value_cast (type, fromval);
1212 else
1213 {
1214 /* Coerce arrays and functions to pointers, except for arrays
1215 which only live in GDB's storage. */
1216 if (!value_must_coerce_to_target (fromval))
1217 fromval = coerce_array (fromval);
1218 }
1219
1220 CHECK_TYPEDEF (type);
1221
1222 /* Since modifying a register can trash the frame chain, and
1223 modifying memory can trash the frame cache, we save the old frame
1224 and then restore the new frame afterwards. */
1225 old_frame = get_frame_id (deprecated_safe_get_selected_frame ());
1226
1227 switch (VALUE_LVAL (toval))
1228 {
1229 case lval_internalvar:
1230 set_internalvar (VALUE_INTERNALVAR (toval), fromval);
1231 return value_of_internalvar (get_type_arch (type),
1232 VALUE_INTERNALVAR (toval));
1233
1234 case lval_internalvar_component:
1235 set_internalvar_component (VALUE_INTERNALVAR (toval),
1236 value_offset (toval),
1237 value_bitpos (toval),
1238 value_bitsize (toval),
1239 fromval);
1240 break;
1241
1242 case lval_memory:
1243 {
1244 const gdb_byte *dest_buffer;
1245 CORE_ADDR changed_addr;
1246 int changed_len;
1247 gdb_byte buffer[sizeof (LONGEST)];
1248
1249 if (value_bitsize (toval))
1250 {
1251 struct value *parent = value_parent (toval);
1252
1253 changed_addr = value_address (parent) + value_offset (toval);
1254 changed_len = (value_bitpos (toval)
1255 + value_bitsize (toval)
1256 + HOST_CHAR_BIT - 1)
1257 / HOST_CHAR_BIT;
1258
1259 /* If we can read-modify-write exactly the size of the
1260 containing type (e.g. short or int) then do so. This
1261 is safer for volatile bitfields mapped to hardware
1262 registers. */
1263 if (changed_len < TYPE_LENGTH (type)
1264 && TYPE_LENGTH (type) <= (int) sizeof (LONGEST)
1265 && ((LONGEST) changed_addr % TYPE_LENGTH (type)) == 0)
1266 changed_len = TYPE_LENGTH (type);
1267
1268 if (changed_len > (int) sizeof (LONGEST))
1269 error (_("Can't handle bitfields which "
1270 "don't fit in a %d bit word."),
1271 (int) sizeof (LONGEST) * HOST_CHAR_BIT);
1272
1273 read_memory (changed_addr, buffer, changed_len);
1274 modify_field (type, buffer, value_as_long (fromval),
1275 value_bitpos (toval), value_bitsize (toval));
1276 dest_buffer = buffer;
1277 }
1278 else
1279 {
1280 changed_addr = value_address (toval);
1281 changed_len = TYPE_LENGTH (type);
1282 dest_buffer = value_contents (fromval);
1283 }
1284
1285 write_memory (changed_addr, dest_buffer, changed_len);
1286 observer_notify_memory_changed (changed_addr, changed_len,
1287 dest_buffer);
1288 }
1289 break;
1290
1291 case lval_register:
1292 {
1293 struct frame_info *frame;
1294 struct gdbarch *gdbarch;
1295 int value_reg;
1296
1297 /* Figure out which frame this is in currently. */
1298 frame = frame_find_by_id (VALUE_FRAME_ID (toval));
1299 value_reg = VALUE_REGNUM (toval);
1300
1301 if (!frame)
1302 error (_("Value being assigned to is no longer active."));
1303
1304 gdbarch = get_frame_arch (frame);
1305 if (gdbarch_convert_register_p (gdbarch, VALUE_REGNUM (toval), type))
1306 {
1307 /* If TOVAL is a special machine register requiring
1308 conversion of program values to a special raw
1309 format. */
1310 gdbarch_value_to_register (gdbarch, frame,
1311 VALUE_REGNUM (toval), type,
1312 value_contents (fromval));
1313 }
1314 else
1315 {
1316 if (value_bitsize (toval))
1317 {
1318 struct value *parent = value_parent (toval);
1319 int offset = value_offset (parent) + value_offset (toval);
1320 int changed_len;
1321 gdb_byte buffer[sizeof (LONGEST)];
1322
1323 changed_len = (value_bitpos (toval)
1324 + value_bitsize (toval)
1325 + HOST_CHAR_BIT - 1)
1326 / HOST_CHAR_BIT;
1327
1328 if (changed_len > (int) sizeof (LONGEST))
1329 error (_("Can't handle bitfields which "
1330 "don't fit in a %d bit word."),
1331 (int) sizeof (LONGEST) * HOST_CHAR_BIT);
1332
1333 get_frame_register_bytes (frame, value_reg, offset,
1334 changed_len, buffer);
1335
1336 modify_field (type, buffer, value_as_long (fromval),
1337 value_bitpos (toval), value_bitsize (toval));
1338
1339 put_frame_register_bytes (frame, value_reg, offset,
1340 changed_len, buffer);
1341 }
1342 else
1343 {
1344 put_frame_register_bytes (frame, value_reg,
1345 value_offset (toval),
1346 TYPE_LENGTH (type),
1347 value_contents (fromval));
1348 }
1349 }
1350
1351 if (deprecated_register_changed_hook)
1352 deprecated_register_changed_hook (-1);
1353 observer_notify_target_changed (&current_target);
1354 break;
1355 }
1356
1357 case lval_computed:
1358 {
1359 struct lval_funcs *funcs = value_computed_funcs (toval);
1360
1361 funcs->write (toval, fromval);
1362 }
1363 break;
1364
1365 default:
1366 error (_("Left operand of assignment is not an lvalue."));
1367 }
1368
1369 /* Assigning to the stack pointer, frame pointer, and other
1370 (architecture and calling convention specific) registers may
1371 cause the frame cache to be out of date. Assigning to memory
1372 also can. We just do this on all assignments to registers or
1373 memory, for simplicity's sake; I doubt the slowdown matters. */
1374 switch (VALUE_LVAL (toval))
1375 {
1376 case lval_memory:
1377 case lval_register:
1378 case lval_computed:
1379
1380 reinit_frame_cache ();
1381
1382 /* Having destroyed the frame cache, restore the selected
1383 frame. */
1384
1385 /* FIXME: cagney/2002-11-02: There has to be a better way of
1386 doing this. Instead of constantly saving/restoring the
1387 frame. Why not create a get_selected_frame() function that,
1388 having saved the selected frame's ID can automatically
1389 re-find the previously selected frame automatically. */
1390
1391 {
1392 struct frame_info *fi = frame_find_by_id (old_frame);
1393
1394 if (fi != NULL)
1395 select_frame (fi);
1396 }
1397
1398 break;
1399 default:
1400 break;
1401 }
1402
1403 /* If the field does not entirely fill a LONGEST, then zero the sign
1404 bits. If the field is signed, and is negative, then sign
1405 extend. */
1406 if ((value_bitsize (toval) > 0)
1407 && (value_bitsize (toval) < 8 * (int) sizeof (LONGEST)))
1408 {
1409 LONGEST fieldval = value_as_long (fromval);
1410 LONGEST valmask = (((ULONGEST) 1) << value_bitsize (toval)) - 1;
1411
1412 fieldval &= valmask;
1413 if (!TYPE_UNSIGNED (type)
1414 && (fieldval & (valmask ^ (valmask >> 1))))
1415 fieldval |= ~valmask;
1416
1417 fromval = value_from_longest (type, fieldval);
1418 }
1419
1420 /* The return value is a copy of TOVAL so it shares its location
1421 information, but its contents are updated from FROMVAL. This
1422 implies the returned value is not lazy, even if TOVAL was. */
1423 val = value_copy (toval);
1424 set_value_lazy (val, 0);
1425 memcpy (value_contents_raw (val), value_contents (fromval),
1426 TYPE_LENGTH (type));
1427
1428 /* We copy over the enclosing type and pointed-to offset from FROMVAL
1429 in the case of pointer types. For object types, the enclosing type
1430 and embedded offset must *not* be copied: the target object refered
1431 to by TOVAL retains its original dynamic type after assignment. */
1432 if (TYPE_CODE (type) == TYPE_CODE_PTR)
1433 {
1434 set_value_enclosing_type (val, value_enclosing_type (fromval));
1435 set_value_pointed_to_offset (val, value_pointed_to_offset (fromval));
1436 }
1437
1438 return val;
1439 }
1440
1441 /* Extend a value VAL to COUNT repetitions of its type. */
1442
1443 struct value *
1444 value_repeat (struct value *arg1, int count)
1445 {
1446 struct value *val;
1447
1448 if (VALUE_LVAL (arg1) != lval_memory)
1449 error (_("Only values in memory can be extended with '@'."));
1450 if (count < 1)
1451 error (_("Invalid number %d of repetitions."), count);
1452
1453 val = allocate_repeat_value (value_enclosing_type (arg1), count);
1454
1455 read_memory (value_address (arg1),
1456 value_contents_all_raw (val),
1457 TYPE_LENGTH (value_enclosing_type (val)));
1458 VALUE_LVAL (val) = lval_memory;
1459 set_value_address (val, value_address (arg1));
1460
1461 return val;
1462 }
1463
1464 struct value *
1465 value_of_variable (struct symbol *var, struct block *b)
1466 {
1467 struct value *val;
1468 struct frame_info *frame;
1469
1470 if (!symbol_read_needs_frame (var))
1471 frame = NULL;
1472 else if (!b)
1473 frame = get_selected_frame (_("No frame selected."));
1474 else
1475 {
1476 frame = block_innermost_frame (b);
1477 if (!frame)
1478 {
1479 if (BLOCK_FUNCTION (b) && !block_inlined_p (b)
1480 && SYMBOL_PRINT_NAME (BLOCK_FUNCTION (b)))
1481 error (_("No frame is currently executing in block %s."),
1482 SYMBOL_PRINT_NAME (BLOCK_FUNCTION (b)));
1483 else
1484 error (_("No frame is currently executing in specified block"));
1485 }
1486 }
1487
1488 val = read_var_value (var, frame);
1489 if (!val)
1490 error (_("Address of symbol \"%s\" is unknown."), SYMBOL_PRINT_NAME (var));
1491
1492 return val;
1493 }
1494
1495 struct value *
1496 address_of_variable (struct symbol *var, struct block *b)
1497 {
1498 struct type *type = SYMBOL_TYPE (var);
1499 struct value *val;
1500
1501 /* Evaluate it first; if the result is a memory address, we're fine.
1502 Lazy evaluation pays off here. */
1503
1504 val = value_of_variable (var, b);
1505
1506 if ((VALUE_LVAL (val) == lval_memory && value_lazy (val))
1507 || TYPE_CODE (type) == TYPE_CODE_FUNC)
1508 {
1509 CORE_ADDR addr = value_address (val);
1510
1511 return value_from_pointer (lookup_pointer_type (type), addr);
1512 }
1513
1514 /* Not a memory address; check what the problem was. */
1515 switch (VALUE_LVAL (val))
1516 {
1517 case lval_register:
1518 {
1519 struct frame_info *frame;
1520 const char *regname;
1521
1522 frame = frame_find_by_id (VALUE_FRAME_ID (val));
1523 gdb_assert (frame);
1524
1525 regname = gdbarch_register_name (get_frame_arch (frame),
1526 VALUE_REGNUM (val));
1527 gdb_assert (regname && *regname);
1528
1529 error (_("Address requested for identifier "
1530 "\"%s\" which is in register $%s"),
1531 SYMBOL_PRINT_NAME (var), regname);
1532 break;
1533 }
1534
1535 default:
1536 error (_("Can't take address of \"%s\" which isn't an lvalue."),
1537 SYMBOL_PRINT_NAME (var));
1538 break;
1539 }
1540
1541 return val;
1542 }
1543
1544 /* Return one if VAL does not live in target memory, but should in order
1545 to operate on it. Otherwise return zero. */
1546
1547 int
1548 value_must_coerce_to_target (struct value *val)
1549 {
1550 struct type *valtype;
1551
1552 /* The only lval kinds which do not live in target memory. */
1553 if (VALUE_LVAL (val) != not_lval
1554 && VALUE_LVAL (val) != lval_internalvar)
1555 return 0;
1556
1557 valtype = check_typedef (value_type (val));
1558
1559 switch (TYPE_CODE (valtype))
1560 {
1561 case TYPE_CODE_ARRAY:
1562 return TYPE_VECTOR (valtype) ? 0 : 1;
1563 case TYPE_CODE_STRING:
1564 return 1;
1565 default:
1566 return 0;
1567 }
1568 }
1569
1570 /* Make sure that VAL lives in target memory if it's supposed to. For
1571 instance, strings are constructed as character arrays in GDB's
1572 storage, and this function copies them to the target. */
1573
1574 struct value *
1575 value_coerce_to_target (struct value *val)
1576 {
1577 LONGEST length;
1578 CORE_ADDR addr;
1579
1580 if (!value_must_coerce_to_target (val))
1581 return val;
1582
1583 length = TYPE_LENGTH (check_typedef (value_type (val)));
1584 addr = allocate_space_in_inferior (length);
1585 write_memory (addr, value_contents (val), length);
1586 return value_at_lazy (value_type (val), addr);
1587 }
1588
1589 /* Given a value which is an array, return a value which is a pointer
1590 to its first element, regardless of whether or not the array has a
1591 nonzero lower bound.
1592
1593 FIXME: A previous comment here indicated that this routine should
1594 be substracting the array's lower bound. It's not clear to me that
1595 this is correct. Given an array subscripting operation, it would
1596 certainly work to do the adjustment here, essentially computing:
1597
1598 (&array[0] - (lowerbound * sizeof array[0])) + (index * sizeof array[0])
1599
1600 However I believe a more appropriate and logical place to account
1601 for the lower bound is to do so in value_subscript, essentially
1602 computing:
1603
1604 (&array[0] + ((index - lowerbound) * sizeof array[0]))
1605
1606 As further evidence consider what would happen with operations
1607 other than array subscripting, where the caller would get back a
1608 value that had an address somewhere before the actual first element
1609 of the array, and the information about the lower bound would be
1610 lost because of the coercion to pointer type. */
1611
1612 struct value *
1613 value_coerce_array (struct value *arg1)
1614 {
1615 struct type *type = check_typedef (value_type (arg1));
1616
1617 /* If the user tries to do something requiring a pointer with an
1618 array that has not yet been pushed to the target, then this would
1619 be a good time to do so. */
1620 arg1 = value_coerce_to_target (arg1);
1621
1622 if (VALUE_LVAL (arg1) != lval_memory)
1623 error (_("Attempt to take address of value not located in memory."));
1624
1625 return value_from_pointer (lookup_pointer_type (TYPE_TARGET_TYPE (type)),
1626 value_address (arg1));
1627 }
1628
1629 /* Given a value which is a function, return a value which is a pointer
1630 to it. */
1631
1632 struct value *
1633 value_coerce_function (struct value *arg1)
1634 {
1635 struct value *retval;
1636
1637 if (VALUE_LVAL (arg1) != lval_memory)
1638 error (_("Attempt to take address of value not located in memory."));
1639
1640 retval = value_from_pointer (lookup_pointer_type (value_type (arg1)),
1641 value_address (arg1));
1642 return retval;
1643 }
1644
1645 /* Return a pointer value for the object for which ARG1 is the
1646 contents. */
1647
1648 struct value *
1649 value_addr (struct value *arg1)
1650 {
1651 struct value *arg2;
1652 struct type *type = check_typedef (value_type (arg1));
1653
1654 if (TYPE_CODE (type) == TYPE_CODE_REF)
1655 {
1656 /* Copy the value, but change the type from (T&) to (T*). We
1657 keep the same location information, which is efficient, and
1658 allows &(&X) to get the location containing the reference. */
1659 arg2 = value_copy (arg1);
1660 deprecated_set_value_type (arg2,
1661 lookup_pointer_type (TYPE_TARGET_TYPE (type)));
1662 return arg2;
1663 }
1664 if (TYPE_CODE (type) == TYPE_CODE_FUNC)
1665 return value_coerce_function (arg1);
1666
1667 /* If this is an array that has not yet been pushed to the target,
1668 then this would be a good time to force it to memory. */
1669 arg1 = value_coerce_to_target (arg1);
1670
1671 if (VALUE_LVAL (arg1) != lval_memory)
1672 error (_("Attempt to take address of value not located in memory."));
1673
1674 /* Get target memory address. */
1675 arg2 = value_from_pointer (lookup_pointer_type (value_type (arg1)),
1676 (value_address (arg1)
1677 + value_embedded_offset (arg1)));
1678
1679 /* This may be a pointer to a base subobject; so remember the
1680 full derived object's type ... */
1681 set_value_enclosing_type (arg2,
1682 lookup_pointer_type (value_enclosing_type (arg1)));
1683 /* ... and also the relative position of the subobject in the full
1684 object. */
1685 set_value_pointed_to_offset (arg2, value_embedded_offset (arg1));
1686 return arg2;
1687 }
1688
1689 /* Return a reference value for the object for which ARG1 is the
1690 contents. */
1691
1692 struct value *
1693 value_ref (struct value *arg1)
1694 {
1695 struct value *arg2;
1696 struct type *type = check_typedef (value_type (arg1));
1697
1698 if (TYPE_CODE (type) == TYPE_CODE_REF)
1699 return arg1;
1700
1701 arg2 = value_addr (arg1);
1702 deprecated_set_value_type (arg2, lookup_reference_type (type));
1703 return arg2;
1704 }
1705
1706 /* Given a value of a pointer type, apply the C unary * operator to
1707 it. */
1708
1709 struct value *
1710 value_ind (struct value *arg1)
1711 {
1712 struct type *base_type;
1713 struct value *arg2;
1714
1715 arg1 = coerce_array (arg1);
1716
1717 base_type = check_typedef (value_type (arg1));
1718
1719 if (VALUE_LVAL (arg1) == lval_computed)
1720 {
1721 struct lval_funcs *funcs = value_computed_funcs (arg1);
1722
1723 if (funcs->indirect)
1724 {
1725 struct value *result = funcs->indirect (arg1);
1726
1727 if (result)
1728 return result;
1729 }
1730 }
1731
1732 if (TYPE_CODE (base_type) == TYPE_CODE_PTR)
1733 {
1734 struct type *enc_type;
1735
1736 /* We may be pointing to something embedded in a larger object.
1737 Get the real type of the enclosing object. */
1738 enc_type = check_typedef (value_enclosing_type (arg1));
1739 enc_type = TYPE_TARGET_TYPE (enc_type);
1740
1741 if (TYPE_CODE (check_typedef (enc_type)) == TYPE_CODE_FUNC
1742 || TYPE_CODE (check_typedef (enc_type)) == TYPE_CODE_METHOD)
1743 /* For functions, go through find_function_addr, which knows
1744 how to handle function descriptors. */
1745 arg2 = value_at_lazy (enc_type,
1746 find_function_addr (arg1, NULL));
1747 else
1748 /* Retrieve the enclosing object pointed to. */
1749 arg2 = value_at_lazy (enc_type,
1750 (value_as_address (arg1)
1751 - value_pointed_to_offset (arg1)));
1752
1753 /* Re-adjust type. */
1754 deprecated_set_value_type (arg2, TYPE_TARGET_TYPE (base_type));
1755 /* Add embedding info. */
1756 set_value_enclosing_type (arg2, enc_type);
1757 set_value_embedded_offset (arg2, value_pointed_to_offset (arg1));
1758
1759 /* We may be pointing to an object of some derived type. */
1760 arg2 = value_full_object (arg2, NULL, 0, 0, 0);
1761 return arg2;
1762 }
1763
1764 error (_("Attempt to take contents of a non-pointer value."));
1765 return 0; /* For lint -- never reached. */
1766 }
1767 \f
1768 /* Create a value for an array by allocating space in GDB, copying
1769 copying the data into that space, and then setting up an array
1770 value.
1771
1772 The array bounds are set from LOWBOUND and HIGHBOUND, and the array
1773 is populated from the values passed in ELEMVEC.
1774
1775 The element type of the array is inherited from the type of the
1776 first element, and all elements must have the same size (though we
1777 don't currently enforce any restriction on their types). */
1778
1779 struct value *
1780 value_array (int lowbound, int highbound, struct value **elemvec)
1781 {
1782 int nelem;
1783 int idx;
1784 unsigned int typelength;
1785 struct value *val;
1786 struct type *arraytype;
1787
1788 /* Validate that the bounds are reasonable and that each of the
1789 elements have the same size. */
1790
1791 nelem = highbound - lowbound + 1;
1792 if (nelem <= 0)
1793 {
1794 error (_("bad array bounds (%d, %d)"), lowbound, highbound);
1795 }
1796 typelength = TYPE_LENGTH (value_enclosing_type (elemvec[0]));
1797 for (idx = 1; idx < nelem; idx++)
1798 {
1799 if (TYPE_LENGTH (value_enclosing_type (elemvec[idx])) != typelength)
1800 {
1801 error (_("array elements must all be the same size"));
1802 }
1803 }
1804
1805 arraytype = lookup_array_range_type (value_enclosing_type (elemvec[0]),
1806 lowbound, highbound);
1807
1808 if (!current_language->c_style_arrays)
1809 {
1810 val = allocate_value (arraytype);
1811 for (idx = 0; idx < nelem; idx++)
1812 {
1813 memcpy (value_contents_all_raw (val) + (idx * typelength),
1814 value_contents_all (elemvec[idx]),
1815 typelength);
1816 }
1817 return val;
1818 }
1819
1820 /* Allocate space to store the array, and then initialize it by
1821 copying in each element. */
1822
1823 val = allocate_value (arraytype);
1824 for (idx = 0; idx < nelem; idx++)
1825 memcpy (value_contents_writeable (val) + (idx * typelength),
1826 value_contents_all (elemvec[idx]),
1827 typelength);
1828 return val;
1829 }
1830
1831 struct value *
1832 value_cstring (char *ptr, int len, struct type *char_type)
1833 {
1834 struct value *val;
1835 int lowbound = current_language->string_lower_bound;
1836 int highbound = len / TYPE_LENGTH (char_type);
1837 struct type *stringtype
1838 = lookup_array_range_type (char_type, lowbound, highbound + lowbound - 1);
1839
1840 val = allocate_value (stringtype);
1841 memcpy (value_contents_raw (val), ptr, len);
1842 return val;
1843 }
1844
1845 /* Create a value for a string constant by allocating space in the
1846 inferior, copying the data into that space, and returning the
1847 address with type TYPE_CODE_STRING. PTR points to the string
1848 constant data; LEN is number of characters.
1849
1850 Note that string types are like array of char types with a lower
1851 bound of zero and an upper bound of LEN - 1. Also note that the
1852 string may contain embedded null bytes. */
1853
1854 struct value *
1855 value_string (char *ptr, int len, struct type *char_type)
1856 {
1857 struct value *val;
1858 int lowbound = current_language->string_lower_bound;
1859 int highbound = len / TYPE_LENGTH (char_type);
1860 struct type *stringtype
1861 = lookup_string_range_type (char_type, lowbound, highbound + lowbound - 1);
1862
1863 val = allocate_value (stringtype);
1864 memcpy (value_contents_raw (val), ptr, len);
1865 return val;
1866 }
1867
1868 struct value *
1869 value_bitstring (char *ptr, int len, struct type *index_type)
1870 {
1871 struct value *val;
1872 struct type *domain_type
1873 = create_range_type (NULL, index_type, 0, len - 1);
1874 struct type *type = create_set_type (NULL, domain_type);
1875
1876 TYPE_CODE (type) = TYPE_CODE_BITSTRING;
1877 val = allocate_value (type);
1878 memcpy (value_contents_raw (val), ptr, TYPE_LENGTH (type));
1879 return val;
1880 }
1881 \f
1882 /* See if we can pass arguments in T2 to a function which takes
1883 arguments of types T1. T1 is a list of NARGS arguments, and T2 is
1884 a NULL-terminated vector. If some arguments need coercion of some
1885 sort, then the coerced values are written into T2. Return value is
1886 0 if the arguments could be matched, or the position at which they
1887 differ if not.
1888
1889 STATICP is nonzero if the T1 argument list came from a static
1890 member function. T2 will still include the ``this'' pointer, but
1891 it will be skipped.
1892
1893 For non-static member functions, we ignore the first argument,
1894 which is the type of the instance variable. This is because we
1895 want to handle calls with objects from derived classes. This is
1896 not entirely correct: we should actually check to make sure that a
1897 requested operation is type secure, shouldn't we? FIXME. */
1898
1899 static int
1900 typecmp (int staticp, int varargs, int nargs,
1901 struct field t1[], struct value *t2[])
1902 {
1903 int i;
1904
1905 if (t2 == 0)
1906 internal_error (__FILE__, __LINE__,
1907 _("typecmp: no argument list"));
1908
1909 /* Skip ``this'' argument if applicable. T2 will always include
1910 THIS. */
1911 if (staticp)
1912 t2 ++;
1913
1914 for (i = 0;
1915 (i < nargs) && TYPE_CODE (t1[i].type) != TYPE_CODE_VOID;
1916 i++)
1917 {
1918 struct type *tt1, *tt2;
1919
1920 if (!t2[i])
1921 return i + 1;
1922
1923 tt1 = check_typedef (t1[i].type);
1924 tt2 = check_typedef (value_type (t2[i]));
1925
1926 if (TYPE_CODE (tt1) == TYPE_CODE_REF
1927 /* We should be doing hairy argument matching, as below. */
1928 && (TYPE_CODE (check_typedef (TYPE_TARGET_TYPE (tt1)))
1929 == TYPE_CODE (tt2)))
1930 {
1931 if (TYPE_CODE (tt2) == TYPE_CODE_ARRAY)
1932 t2[i] = value_coerce_array (t2[i]);
1933 else
1934 t2[i] = value_ref (t2[i]);
1935 continue;
1936 }
1937
1938 /* djb - 20000715 - Until the new type structure is in the
1939 place, and we can attempt things like implicit conversions,
1940 we need to do this so you can take something like a map<const
1941 char *>, and properly access map["hello"], because the
1942 argument to [] will be a reference to a pointer to a char,
1943 and the argument will be a pointer to a char. */
1944 while (TYPE_CODE(tt1) == TYPE_CODE_REF
1945 || TYPE_CODE (tt1) == TYPE_CODE_PTR)
1946 {
1947 tt1 = check_typedef( TYPE_TARGET_TYPE(tt1) );
1948 }
1949 while (TYPE_CODE(tt2) == TYPE_CODE_ARRAY
1950 || TYPE_CODE(tt2) == TYPE_CODE_PTR
1951 || TYPE_CODE(tt2) == TYPE_CODE_REF)
1952 {
1953 tt2 = check_typedef (TYPE_TARGET_TYPE(tt2));
1954 }
1955 if (TYPE_CODE (tt1) == TYPE_CODE (tt2))
1956 continue;
1957 /* Array to pointer is a `trivial conversion' according to the
1958 ARM. */
1959
1960 /* We should be doing much hairier argument matching (see
1961 section 13.2 of the ARM), but as a quick kludge, just check
1962 for the same type code. */
1963 if (TYPE_CODE (t1[i].type) != TYPE_CODE (value_type (t2[i])))
1964 return i + 1;
1965 }
1966 if (varargs || t2[i] == NULL)
1967 return 0;
1968 return i + 1;
1969 }
1970
1971 /* Helper function used by value_struct_elt to recurse through
1972 baseclasses. Look for a field NAME in ARG1. Adjust the address of
1973 ARG1 by OFFSET bytes, and search in it assuming it has (class) type
1974 TYPE. If found, return value, else return NULL.
1975
1976 If LOOKING_FOR_BASECLASS, then instead of looking for struct
1977 fields, look for a baseclass named NAME. */
1978
1979 static struct value *
1980 search_struct_field (const char *name, struct value *arg1, int offset,
1981 struct type *type, int looking_for_baseclass)
1982 {
1983 int i;
1984 int nbases;
1985
1986 CHECK_TYPEDEF (type);
1987 nbases = TYPE_N_BASECLASSES (type);
1988
1989 if (!looking_for_baseclass)
1990 for (i = TYPE_NFIELDS (type) - 1; i >= nbases; i--)
1991 {
1992 char *t_field_name = TYPE_FIELD_NAME (type, i);
1993
1994 if (t_field_name && (strcmp_iw (t_field_name, name) == 0))
1995 {
1996 struct value *v;
1997
1998 if (field_is_static (&TYPE_FIELD (type, i)))
1999 {
2000 v = value_static_field (type, i);
2001 if (v == 0)
2002 error (_("field %s is nonexistent or "
2003 "has been optimized out"),
2004 name);
2005 }
2006 else
2007 {
2008 v = value_primitive_field (arg1, offset, i, type);
2009 if (v == 0)
2010 error (_("there is no field named %s"), name);
2011 }
2012 return v;
2013 }
2014
2015 if (t_field_name
2016 && (t_field_name[0] == '\0'
2017 || (TYPE_CODE (type) == TYPE_CODE_UNION
2018 && (strcmp_iw (t_field_name, "else") == 0))))
2019 {
2020 struct type *field_type = TYPE_FIELD_TYPE (type, i);
2021
2022 if (TYPE_CODE (field_type) == TYPE_CODE_UNION
2023 || TYPE_CODE (field_type) == TYPE_CODE_STRUCT)
2024 {
2025 /* Look for a match through the fields of an anonymous
2026 union, or anonymous struct. C++ provides anonymous
2027 unions.
2028
2029 In the GNU Chill (now deleted from GDB)
2030 implementation of variant record types, each
2031 <alternative field> has an (anonymous) union type,
2032 each member of the union represents a <variant
2033 alternative>. Each <variant alternative> is
2034 represented as a struct, with a member for each
2035 <variant field>. */
2036
2037 struct value *v;
2038 int new_offset = offset;
2039
2040 /* This is pretty gross. In G++, the offset in an
2041 anonymous union is relative to the beginning of the
2042 enclosing struct. In the GNU Chill (now deleted
2043 from GDB) implementation of variant records, the
2044 bitpos is zero in an anonymous union field, so we
2045 have to add the offset of the union here. */
2046 if (TYPE_CODE (field_type) == TYPE_CODE_STRUCT
2047 || (TYPE_NFIELDS (field_type) > 0
2048 && TYPE_FIELD_BITPOS (field_type, 0) == 0))
2049 new_offset += TYPE_FIELD_BITPOS (type, i) / 8;
2050
2051 v = search_struct_field (name, arg1, new_offset,
2052 field_type,
2053 looking_for_baseclass);
2054 if (v)
2055 return v;
2056 }
2057 }
2058 }
2059
2060 for (i = 0; i < nbases; i++)
2061 {
2062 struct value *v;
2063 struct type *basetype = check_typedef (TYPE_BASECLASS (type, i));
2064 /* If we are looking for baseclasses, this is what we get when
2065 we hit them. But it could happen that the base part's member
2066 name is not yet filled in. */
2067 int found_baseclass = (looking_for_baseclass
2068 && TYPE_BASECLASS_NAME (type, i) != NULL
2069 && (strcmp_iw (name,
2070 TYPE_BASECLASS_NAME (type,
2071 i)) == 0));
2072
2073 if (BASETYPE_VIA_VIRTUAL (type, i))
2074 {
2075 int boffset;
2076 struct value *v2;
2077
2078 boffset = baseclass_offset (type, i,
2079 value_contents (arg1) + offset,
2080 value_address (arg1)
2081 + value_embedded_offset (arg1)
2082 + offset);
2083 if (boffset == -1)
2084 error (_("virtual baseclass botch"));
2085
2086 /* The virtual base class pointer might have been clobbered
2087 by the user program. Make sure that it still points to a
2088 valid memory location. */
2089
2090 boffset += value_embedded_offset (arg1) + offset;
2091 if (boffset < 0
2092 || boffset >= TYPE_LENGTH (value_enclosing_type (arg1)))
2093 {
2094 CORE_ADDR base_addr;
2095
2096 v2 = allocate_value (basetype);
2097 base_addr = value_address (arg1) + boffset;
2098 if (target_read_memory (base_addr,
2099 value_contents_raw (v2),
2100 TYPE_LENGTH (basetype)) != 0)
2101 error (_("virtual baseclass botch"));
2102 VALUE_LVAL (v2) = lval_memory;
2103 set_value_address (v2, base_addr);
2104 }
2105 else
2106 {
2107 v2 = value_copy (arg1);
2108 deprecated_set_value_type (v2, basetype);
2109 set_value_embedded_offset (v2, boffset);
2110 }
2111
2112 if (found_baseclass)
2113 return v2;
2114 v = search_struct_field (name, v2, 0,
2115 TYPE_BASECLASS (type, i),
2116 looking_for_baseclass);
2117 }
2118 else if (found_baseclass)
2119 v = value_primitive_field (arg1, offset, i, type);
2120 else
2121 v = search_struct_field (name, arg1,
2122 offset + TYPE_BASECLASS_BITPOS (type,
2123 i) / 8,
2124 basetype, looking_for_baseclass);
2125 if (v)
2126 return v;
2127 }
2128 return NULL;
2129 }
2130
2131 /* Helper function used by value_struct_elt to recurse through
2132 baseclasses. Look for a field NAME in ARG1. Adjust the address of
2133 ARG1 by OFFSET bytes, and search in it assuming it has (class) type
2134 TYPE.
2135
2136 If found, return value, else if name matched and args not return
2137 (value) -1, else return NULL. */
2138
2139 static struct value *
2140 search_struct_method (const char *name, struct value **arg1p,
2141 struct value **args, int offset,
2142 int *static_memfuncp, struct type *type)
2143 {
2144 int i;
2145 struct value *v;
2146 int name_matched = 0;
2147 char dem_opname[64];
2148
2149 CHECK_TYPEDEF (type);
2150 for (i = TYPE_NFN_FIELDS (type) - 1; i >= 0; i--)
2151 {
2152 char *t_field_name = TYPE_FN_FIELDLIST_NAME (type, i);
2153
2154 /* FIXME! May need to check for ARM demangling here. */
2155 if (strncmp (t_field_name, "__", 2) == 0 ||
2156 strncmp (t_field_name, "op", 2) == 0 ||
2157 strncmp (t_field_name, "type", 4) == 0)
2158 {
2159 if (cplus_demangle_opname (t_field_name, dem_opname, DMGL_ANSI))
2160 t_field_name = dem_opname;
2161 else if (cplus_demangle_opname (t_field_name, dem_opname, 0))
2162 t_field_name = dem_opname;
2163 }
2164 if (t_field_name && (strcmp_iw (t_field_name, name) == 0))
2165 {
2166 int j = TYPE_FN_FIELDLIST_LENGTH (type, i) - 1;
2167 struct fn_field *f = TYPE_FN_FIELDLIST1 (type, i);
2168
2169 name_matched = 1;
2170 check_stub_method_group (type, i);
2171 if (j > 0 && args == 0)
2172 error (_("cannot resolve overloaded method "
2173 "`%s': no arguments supplied"), name);
2174 else if (j == 0 && args == 0)
2175 {
2176 v = value_fn_field (arg1p, f, j, type, offset);
2177 if (v != NULL)
2178 return v;
2179 }
2180 else
2181 while (j >= 0)
2182 {
2183 if (!typecmp (TYPE_FN_FIELD_STATIC_P (f, j),
2184 TYPE_VARARGS (TYPE_FN_FIELD_TYPE (f, j)),
2185 TYPE_NFIELDS (TYPE_FN_FIELD_TYPE (f, j)),
2186 TYPE_FN_FIELD_ARGS (f, j), args))
2187 {
2188 if (TYPE_FN_FIELD_VIRTUAL_P (f, j))
2189 return value_virtual_fn_field (arg1p, f, j,
2190 type, offset);
2191 if (TYPE_FN_FIELD_STATIC_P (f, j)
2192 && static_memfuncp)
2193 *static_memfuncp = 1;
2194 v = value_fn_field (arg1p, f, j, type, offset);
2195 if (v != NULL)
2196 return v;
2197 }
2198 j--;
2199 }
2200 }
2201 }
2202
2203 for (i = TYPE_N_BASECLASSES (type) - 1; i >= 0; i--)
2204 {
2205 int base_offset;
2206
2207 if (BASETYPE_VIA_VIRTUAL (type, i))
2208 {
2209 struct type *baseclass = check_typedef (TYPE_BASECLASS (type, i));
2210 const gdb_byte *base_valaddr;
2211
2212 /* The virtual base class pointer might have been
2213 clobbered by the user program. Make sure that it
2214 still points to a valid memory location. */
2215
2216 if (offset < 0 || offset >= TYPE_LENGTH (type))
2217 {
2218 gdb_byte *tmp = alloca (TYPE_LENGTH (baseclass));
2219
2220 if (target_read_memory (value_address (*arg1p) + offset,
2221 tmp, TYPE_LENGTH (baseclass)) != 0)
2222 error (_("virtual baseclass botch"));
2223 base_valaddr = tmp;
2224 }
2225 else
2226 base_valaddr = value_contents (*arg1p) + offset;
2227
2228 base_offset = baseclass_offset (type, i, base_valaddr,
2229 value_address (*arg1p) + offset);
2230 if (base_offset == -1)
2231 error (_("virtual baseclass botch"));
2232 }
2233 else
2234 {
2235 base_offset = TYPE_BASECLASS_BITPOS (type, i) / 8;
2236 }
2237 v = search_struct_method (name, arg1p, args, base_offset + offset,
2238 static_memfuncp, TYPE_BASECLASS (type, i));
2239 if (v == (struct value *) - 1)
2240 {
2241 name_matched = 1;
2242 }
2243 else if (v)
2244 {
2245 /* FIXME-bothner: Why is this commented out? Why is it here? */
2246 /* *arg1p = arg1_tmp; */
2247 return v;
2248 }
2249 }
2250 if (name_matched)
2251 return (struct value *) - 1;
2252 else
2253 return NULL;
2254 }
2255
2256 /* Given *ARGP, a value of type (pointer to a)* structure/union,
2257 extract the component named NAME from the ultimate target
2258 structure/union and return it as a value with its appropriate type.
2259 ERR is used in the error message if *ARGP's type is wrong.
2260
2261 C++: ARGS is a list of argument types to aid in the selection of
2262 an appropriate method. Also, handle derived types.
2263
2264 STATIC_MEMFUNCP, if non-NULL, points to a caller-supplied location
2265 where the truthvalue of whether the function that was resolved was
2266 a static member function or not is stored.
2267
2268 ERR is an error message to be printed in case the field is not
2269 found. */
2270
2271 struct value *
2272 value_struct_elt (struct value **argp, struct value **args,
2273 const char *name, int *static_memfuncp, const char *err)
2274 {
2275 struct type *t;
2276 struct value *v;
2277
2278 *argp = coerce_array (*argp);
2279
2280 t = check_typedef (value_type (*argp));
2281
2282 /* Follow pointers until we get to a non-pointer. */
2283
2284 while (TYPE_CODE (t) == TYPE_CODE_PTR || TYPE_CODE (t) == TYPE_CODE_REF)
2285 {
2286 *argp = value_ind (*argp);
2287 /* Don't coerce fn pointer to fn and then back again! */
2288 if (TYPE_CODE (value_type (*argp)) != TYPE_CODE_FUNC)
2289 *argp = coerce_array (*argp);
2290 t = check_typedef (value_type (*argp));
2291 }
2292
2293 if (TYPE_CODE (t) != TYPE_CODE_STRUCT
2294 && TYPE_CODE (t) != TYPE_CODE_UNION)
2295 error (_("Attempt to extract a component of a value that is not a %s."),
2296 err);
2297
2298 /* Assume it's not, unless we see that it is. */
2299 if (static_memfuncp)
2300 *static_memfuncp = 0;
2301
2302 if (!args)
2303 {
2304 /* if there are no arguments ...do this... */
2305
2306 /* Try as a field first, because if we succeed, there is less
2307 work to be done. */
2308 v = search_struct_field (name, *argp, 0, t, 0);
2309 if (v)
2310 return v;
2311
2312 /* C++: If it was not found as a data field, then try to
2313 return it as a pointer to a method. */
2314 v = search_struct_method (name, argp, args, 0,
2315 static_memfuncp, t);
2316
2317 if (v == (struct value *) - 1)
2318 error (_("Cannot take address of method %s."), name);
2319 else if (v == 0)
2320 {
2321 if (TYPE_NFN_FIELDS (t))
2322 error (_("There is no member or method named %s."), name);
2323 else
2324 error (_("There is no member named %s."), name);
2325 }
2326 return v;
2327 }
2328
2329 v = search_struct_method (name, argp, args, 0,
2330 static_memfuncp, t);
2331
2332 if (v == (struct value *) - 1)
2333 {
2334 error (_("One of the arguments you tried to pass to %s could not "
2335 "be converted to what the function wants."), name);
2336 }
2337 else if (v == 0)
2338 {
2339 /* See if user tried to invoke data as function. If so, hand it
2340 back. If it's not callable (i.e., a pointer to function),
2341 gdb should give an error. */
2342 v = search_struct_field (name, *argp, 0, t, 0);
2343 /* If we found an ordinary field, then it is not a method call.
2344 So, treat it as if it were a static member function. */
2345 if (v && static_memfuncp)
2346 *static_memfuncp = 1;
2347 }
2348
2349 if (!v)
2350 throw_error (NOT_FOUND_ERROR,
2351 _("Structure has no component named %s."), name);
2352 return v;
2353 }
2354
2355 /* Search through the methods of an object (and its bases) to find a
2356 specified method. Return the pointer to the fn_field list of
2357 overloaded instances.
2358
2359 Helper function for value_find_oload_list.
2360 ARGP is a pointer to a pointer to a value (the object).
2361 METHOD is a string containing the method name.
2362 OFFSET is the offset within the value.
2363 TYPE is the assumed type of the object.
2364 NUM_FNS is the number of overloaded instances.
2365 BASETYPE is set to the actual type of the subobject where the
2366 method is found.
2367 BOFFSET is the offset of the base subobject where the method is found. */
2368
2369 static struct fn_field *
2370 find_method_list (struct value **argp, const char *method,
2371 int offset, struct type *type, int *num_fns,
2372 struct type **basetype, int *boffset)
2373 {
2374 int i;
2375 struct fn_field *f;
2376 CHECK_TYPEDEF (type);
2377
2378 *num_fns = 0;
2379
2380 /* First check in object itself. */
2381 for (i = TYPE_NFN_FIELDS (type) - 1; i >= 0; i--)
2382 {
2383 /* pai: FIXME What about operators and type conversions? */
2384 char *fn_field_name = TYPE_FN_FIELDLIST_NAME (type, i);
2385
2386 if (fn_field_name && (strcmp_iw (fn_field_name, method) == 0))
2387 {
2388 int len = TYPE_FN_FIELDLIST_LENGTH (type, i);
2389 struct fn_field *f = TYPE_FN_FIELDLIST1 (type, i);
2390
2391 *num_fns = len;
2392 *basetype = type;
2393 *boffset = offset;
2394
2395 /* Resolve any stub methods. */
2396 check_stub_method_group (type, i);
2397
2398 return f;
2399 }
2400 }
2401
2402 /* Not found in object, check in base subobjects. */
2403 for (i = TYPE_N_BASECLASSES (type) - 1; i >= 0; i--)
2404 {
2405 int base_offset;
2406
2407 if (BASETYPE_VIA_VIRTUAL (type, i))
2408 {
2409 base_offset = value_offset (*argp) + offset;
2410 base_offset = baseclass_offset (type, i,
2411 value_contents (*argp) + base_offset,
2412 value_address (*argp) + base_offset);
2413 if (base_offset == -1)
2414 error (_("virtual baseclass botch"));
2415 }
2416 else /* Non-virtual base, simply use bit position from debug
2417 info. */
2418 {
2419 base_offset = TYPE_BASECLASS_BITPOS (type, i) / 8;
2420 }
2421 f = find_method_list (argp, method, base_offset + offset,
2422 TYPE_BASECLASS (type, i), num_fns,
2423 basetype, boffset);
2424 if (f)
2425 return f;
2426 }
2427 return NULL;
2428 }
2429
2430 /* Return the list of overloaded methods of a specified name.
2431
2432 ARGP is a pointer to a pointer to a value (the object).
2433 METHOD is the method name.
2434 OFFSET is the offset within the value contents.
2435 NUM_FNS is the number of overloaded instances.
2436 BASETYPE is set to the type of the base subobject that defines the
2437 method.
2438 BOFFSET is the offset of the base subobject which defines the method. */
2439
2440 struct fn_field *
2441 value_find_oload_method_list (struct value **argp, const char *method,
2442 int offset, int *num_fns,
2443 struct type **basetype, int *boffset)
2444 {
2445 struct type *t;
2446
2447 t = check_typedef (value_type (*argp));
2448
2449 /* Code snarfed from value_struct_elt. */
2450 while (TYPE_CODE (t) == TYPE_CODE_PTR || TYPE_CODE (t) == TYPE_CODE_REF)
2451 {
2452 *argp = value_ind (*argp);
2453 /* Don't coerce fn pointer to fn and then back again! */
2454 if (TYPE_CODE (value_type (*argp)) != TYPE_CODE_FUNC)
2455 *argp = coerce_array (*argp);
2456 t = check_typedef (value_type (*argp));
2457 }
2458
2459 if (TYPE_CODE (t) != TYPE_CODE_STRUCT
2460 && TYPE_CODE (t) != TYPE_CODE_UNION)
2461 error (_("Attempt to extract a component of a "
2462 "value that is not a struct or union"));
2463
2464 return find_method_list (argp, method, 0, t, num_fns,
2465 basetype, boffset);
2466 }
2467
2468 /* Given an array of argument types (ARGTYPES) (which includes an
2469 entry for "this" in the case of C++ methods), the number of
2470 arguments NARGS, the NAME of a function whether it's a method or
2471 not (METHOD), and the degree of laxness (LAX) in conforming to
2472 overload resolution rules in ANSI C++, find the best function that
2473 matches on the argument types according to the overload resolution
2474 rules.
2475
2476 METHOD can be one of three values:
2477 NON_METHOD for non-member functions.
2478 METHOD: for member functions.
2479 BOTH: used for overload resolution of operators where the
2480 candidates are expected to be either member or non member
2481 functions. In this case the first argument ARGTYPES
2482 (representing 'this') is expected to be a reference to the
2483 target object, and will be dereferenced when attempting the
2484 non-member search.
2485
2486 In the case of class methods, the parameter OBJ is an object value
2487 in which to search for overloaded methods.
2488
2489 In the case of non-method functions, the parameter FSYM is a symbol
2490 corresponding to one of the overloaded functions.
2491
2492 Return value is an integer: 0 -> good match, 10 -> debugger applied
2493 non-standard coercions, 100 -> incompatible.
2494
2495 If a method is being searched for, VALP will hold the value.
2496 If a non-method is being searched for, SYMP will hold the symbol
2497 for it.
2498
2499 If a method is being searched for, and it is a static method,
2500 then STATICP will point to a non-zero value.
2501
2502 If NO_ADL argument dependent lookup is disabled. This is used to prevent
2503 ADL overload candidates when performing overload resolution for a fully
2504 qualified name.
2505
2506 Note: This function does *not* check the value of
2507 overload_resolution. Caller must check it to see whether overload
2508 resolution is permitted. */
2509
2510 int
2511 find_overload_match (struct type **arg_types, int nargs,
2512 const char *name, enum oload_search_type method,
2513 int lax, struct value **objp, struct symbol *fsym,
2514 struct value **valp, struct symbol **symp,
2515 int *staticp, const int no_adl)
2516 {
2517 struct value *obj = (objp ? *objp : NULL);
2518 /* Index of best overloaded function. */
2519 int func_oload_champ = -1;
2520 int method_oload_champ = -1;
2521
2522 /* The measure for the current best match. */
2523 struct badness_vector *method_badness = NULL;
2524 struct badness_vector *func_badness = NULL;
2525
2526 struct value *temp = obj;
2527 /* For methods, the list of overloaded methods. */
2528 struct fn_field *fns_ptr = NULL;
2529 /* For non-methods, the list of overloaded function symbols. */
2530 struct symbol **oload_syms = NULL;
2531 /* Number of overloaded instances being considered. */
2532 int num_fns = 0;
2533 struct type *basetype = NULL;
2534 int boffset;
2535
2536 struct cleanup *all_cleanups = make_cleanup (null_cleanup, NULL);
2537
2538 const char *obj_type_name = NULL;
2539 const char *func_name = NULL;
2540 enum oload_classification match_quality;
2541 enum oload_classification method_match_quality = INCOMPATIBLE;
2542 enum oload_classification func_match_quality = INCOMPATIBLE;
2543
2544 /* Get the list of overloaded methods or functions. */
2545 if (method == METHOD || method == BOTH)
2546 {
2547 gdb_assert (obj);
2548
2549 /* OBJ may be a pointer value rather than the object itself. */
2550 obj = coerce_ref (obj);
2551 while (TYPE_CODE (check_typedef (value_type (obj))) == TYPE_CODE_PTR)
2552 obj = coerce_ref (value_ind (obj));
2553 obj_type_name = TYPE_NAME (value_type (obj));
2554
2555 /* First check whether this is a data member, e.g. a pointer to
2556 a function. */
2557 if (TYPE_CODE (check_typedef (value_type (obj))) == TYPE_CODE_STRUCT)
2558 {
2559 *valp = search_struct_field (name, obj, 0,
2560 check_typedef (value_type (obj)), 0);
2561 if (*valp)
2562 {
2563 *staticp = 1;
2564 return 0;
2565 }
2566 }
2567
2568 /* Retrieve the list of methods with the name NAME. */
2569 fns_ptr = value_find_oload_method_list (&temp, name,
2570 0, &num_fns,
2571 &basetype, &boffset);
2572 /* If this is a method only search, and no methods were found
2573 the search has faild. */
2574 if (method == METHOD && (!fns_ptr || !num_fns))
2575 error (_("Couldn't find method %s%s%s"),
2576 obj_type_name,
2577 (obj_type_name && *obj_type_name) ? "::" : "",
2578 name);
2579 /* If we are dealing with stub method types, they should have
2580 been resolved by find_method_list via
2581 value_find_oload_method_list above. */
2582 if (fns_ptr)
2583 {
2584 gdb_assert (TYPE_DOMAIN_TYPE (fns_ptr[0].type) != NULL);
2585 method_oload_champ = find_oload_champ (arg_types, nargs, method,
2586 num_fns, fns_ptr,
2587 oload_syms, &method_badness);
2588
2589 method_match_quality =
2590 classify_oload_match (method_badness, nargs,
2591 oload_method_static (method, fns_ptr,
2592 method_oload_champ));
2593
2594 make_cleanup (xfree, method_badness);
2595 }
2596
2597 }
2598
2599 if (method == NON_METHOD || method == BOTH)
2600 {
2601 const char *qualified_name = NULL;
2602
2603 /* If the the overload match is being search for both
2604 as a method and non member function, the first argument
2605 must now be dereferenced. */
2606 if (method == BOTH)
2607 arg_types[0] = TYPE_TARGET_TYPE (arg_types[0]);
2608
2609 if (fsym)
2610 {
2611 qualified_name = SYMBOL_NATURAL_NAME (fsym);
2612
2613 /* If we have a function with a C++ name, try to extract just
2614 the function part. Do not try this for non-functions (e.g.
2615 function pointers). */
2616 if (qualified_name
2617 && TYPE_CODE (check_typedef (SYMBOL_TYPE (fsym)))
2618 == TYPE_CODE_FUNC)
2619 {
2620 char *temp;
2621
2622 temp = cp_func_name (qualified_name);
2623
2624 /* If cp_func_name did not remove anything, the name of the
2625 symbol did not include scope or argument types - it was
2626 probably a C-style function. */
2627 if (temp)
2628 {
2629 make_cleanup (xfree, temp);
2630 if (strcmp (temp, qualified_name) == 0)
2631 func_name = NULL;
2632 else
2633 func_name = temp;
2634 }
2635 }
2636 }
2637 else
2638 {
2639 func_name = name;
2640 qualified_name = name;
2641 }
2642
2643 /* If there was no C++ name, this must be a C-style function or
2644 not a function at all. Just return the same symbol. Do the
2645 same if cp_func_name fails for some reason. */
2646 if (func_name == NULL)
2647 {
2648 *symp = fsym;
2649 return 0;
2650 }
2651
2652 func_oload_champ = find_oload_champ_namespace (arg_types, nargs,
2653 func_name,
2654 qualified_name,
2655 &oload_syms,
2656 &func_badness,
2657 no_adl);
2658
2659 if (func_oload_champ >= 0)
2660 func_match_quality = classify_oload_match (func_badness, nargs, 0);
2661
2662 make_cleanup (xfree, oload_syms);
2663 make_cleanup (xfree, func_badness);
2664 }
2665
2666 /* Did we find a match ? */
2667 if (method_oload_champ == -1 && func_oload_champ == -1)
2668 throw_error (NOT_FOUND_ERROR,
2669 _("No symbol \"%s\" in current context."),
2670 name);
2671
2672 /* If we have found both a method match and a function
2673 match, find out which one is better, and calculate match
2674 quality. */
2675 if (method_oload_champ >= 0 && func_oload_champ >= 0)
2676 {
2677 switch (compare_badness (func_badness, method_badness))
2678 {
2679 case 0: /* Top two contenders are equally good. */
2680 /* FIXME: GDB does not support the general ambiguous
2681 case. All candidates should be collected and presented
2682 the the user. */
2683 error (_("Ambiguous overload resolution"));
2684 break;
2685 case 1: /* Incomparable top contenders. */
2686 /* This is an error incompatible candidates
2687 should not have been proposed. */
2688 error (_("Internal error: incompatible "
2689 "overload candidates proposed"));
2690 break;
2691 case 2: /* Function champion. */
2692 method_oload_champ = -1;
2693 match_quality = func_match_quality;
2694 break;
2695 case 3: /* Method champion. */
2696 func_oload_champ = -1;
2697 match_quality = method_match_quality;
2698 break;
2699 default:
2700 error (_("Internal error: unexpected overload comparison result"));
2701 break;
2702 }
2703 }
2704 else
2705 {
2706 /* We have either a method match or a function match. */
2707 if (method_oload_champ >= 0)
2708 match_quality = method_match_quality;
2709 else
2710 match_quality = func_match_quality;
2711 }
2712
2713 if (match_quality == INCOMPATIBLE)
2714 {
2715 if (method == METHOD)
2716 error (_("Cannot resolve method %s%s%s to any overloaded instance"),
2717 obj_type_name,
2718 (obj_type_name && *obj_type_name) ? "::" : "",
2719 name);
2720 else
2721 error (_("Cannot resolve function %s to any overloaded instance"),
2722 func_name);
2723 }
2724 else if (match_quality == NON_STANDARD)
2725 {
2726 if (method == METHOD)
2727 warning (_("Using non-standard conversion to match "
2728 "method %s%s%s to supplied arguments"),
2729 obj_type_name,
2730 (obj_type_name && *obj_type_name) ? "::" : "",
2731 name);
2732 else
2733 warning (_("Using non-standard conversion to match "
2734 "function %s to supplied arguments"),
2735 func_name);
2736 }
2737
2738 if (staticp != NULL)
2739 *staticp = oload_method_static (method, fns_ptr, method_oload_champ);
2740
2741 if (method_oload_champ >= 0)
2742 {
2743 if (TYPE_FN_FIELD_VIRTUAL_P (fns_ptr, method_oload_champ))
2744 *valp = value_virtual_fn_field (&temp, fns_ptr, method_oload_champ,
2745 basetype, boffset);
2746 else
2747 *valp = value_fn_field (&temp, fns_ptr, method_oload_champ,
2748 basetype, boffset);
2749 }
2750 else
2751 *symp = oload_syms[func_oload_champ];
2752
2753 if (objp)
2754 {
2755 struct type *temp_type = check_typedef (value_type (temp));
2756 struct type *obj_type = check_typedef (value_type (*objp));
2757
2758 if (TYPE_CODE (temp_type) != TYPE_CODE_PTR
2759 && (TYPE_CODE (obj_type) == TYPE_CODE_PTR
2760 || TYPE_CODE (obj_type) == TYPE_CODE_REF))
2761 {
2762 temp = value_addr (temp);
2763 }
2764 *objp = temp;
2765 }
2766
2767 do_cleanups (all_cleanups);
2768
2769 switch (match_quality)
2770 {
2771 case INCOMPATIBLE:
2772 return 100;
2773 case NON_STANDARD:
2774 return 10;
2775 default: /* STANDARD */
2776 return 0;
2777 }
2778 }
2779
2780 /* Find the best overload match, searching for FUNC_NAME in namespaces
2781 contained in QUALIFIED_NAME until it either finds a good match or
2782 runs out of namespaces. It stores the overloaded functions in
2783 *OLOAD_SYMS, and the badness vector in *OLOAD_CHAMP_BV. The
2784 calling function is responsible for freeing *OLOAD_SYMS and
2785 *OLOAD_CHAMP_BV. If NO_ADL, argument dependent lookup is not
2786 performned. */
2787
2788 static int
2789 find_oload_champ_namespace (struct type **arg_types, int nargs,
2790 const char *func_name,
2791 const char *qualified_name,
2792 struct symbol ***oload_syms,
2793 struct badness_vector **oload_champ_bv,
2794 const int no_adl)
2795 {
2796 int oload_champ;
2797
2798 find_oload_champ_namespace_loop (arg_types, nargs,
2799 func_name,
2800 qualified_name, 0,
2801 oload_syms, oload_champ_bv,
2802 &oload_champ,
2803 no_adl);
2804
2805 return oload_champ;
2806 }
2807
2808 /* Helper function for find_oload_champ_namespace; NAMESPACE_LEN is
2809 how deep we've looked for namespaces, and the champ is stored in
2810 OLOAD_CHAMP. The return value is 1 if the champ is a good one, 0
2811 if it isn't. Other arguments are the same as in
2812 find_oload_champ_namespace
2813
2814 It is the caller's responsibility to free *OLOAD_SYMS and
2815 *OLOAD_CHAMP_BV. */
2816
2817 static int
2818 find_oload_champ_namespace_loop (struct type **arg_types, int nargs,
2819 const char *func_name,
2820 const char *qualified_name,
2821 int namespace_len,
2822 struct symbol ***oload_syms,
2823 struct badness_vector **oload_champ_bv,
2824 int *oload_champ,
2825 const int no_adl)
2826 {
2827 int next_namespace_len = namespace_len;
2828 int searched_deeper = 0;
2829 int num_fns = 0;
2830 struct cleanup *old_cleanups;
2831 int new_oload_champ;
2832 struct symbol **new_oload_syms;
2833 struct badness_vector *new_oload_champ_bv;
2834 char *new_namespace;
2835
2836 if (next_namespace_len != 0)
2837 {
2838 gdb_assert (qualified_name[next_namespace_len] == ':');
2839 next_namespace_len += 2;
2840 }
2841 next_namespace_len +=
2842 cp_find_first_component (qualified_name + next_namespace_len);
2843
2844 /* Initialize these to values that can safely be xfree'd. */
2845 *oload_syms = NULL;
2846 *oload_champ_bv = NULL;
2847
2848 /* First, see if we have a deeper namespace we can search in.
2849 If we get a good match there, use it. */
2850
2851 if (qualified_name[next_namespace_len] == ':')
2852 {
2853 searched_deeper = 1;
2854
2855 if (find_oload_champ_namespace_loop (arg_types, nargs,
2856 func_name, qualified_name,
2857 next_namespace_len,
2858 oload_syms, oload_champ_bv,
2859 oload_champ, no_adl))
2860 {
2861 return 1;
2862 }
2863 };
2864
2865 /* If we reach here, either we're in the deepest namespace or we
2866 didn't find a good match in a deeper namespace. But, in the
2867 latter case, we still have a bad match in a deeper namespace;
2868 note that we might not find any match at all in the current
2869 namespace. (There's always a match in the deepest namespace,
2870 because this overload mechanism only gets called if there's a
2871 function symbol to start off with.) */
2872
2873 old_cleanups = make_cleanup (xfree, *oload_syms);
2874 make_cleanup (xfree, *oload_champ_bv);
2875 new_namespace = alloca (namespace_len + 1);
2876 strncpy (new_namespace, qualified_name, namespace_len);
2877 new_namespace[namespace_len] = '\0';
2878 new_oload_syms = make_symbol_overload_list (func_name,
2879 new_namespace);
2880
2881 /* If we have reached the deepest level perform argument
2882 determined lookup. */
2883 if (!searched_deeper && !no_adl)
2884 make_symbol_overload_list_adl (arg_types, nargs, func_name);
2885
2886 while (new_oload_syms[num_fns])
2887 ++num_fns;
2888
2889 new_oload_champ = find_oload_champ (arg_types, nargs, 0, num_fns,
2890 NULL, new_oload_syms,
2891 &new_oload_champ_bv);
2892
2893 /* Case 1: We found a good match. Free earlier matches (if any),
2894 and return it. Case 2: We didn't find a good match, but we're
2895 not the deepest function. Then go with the bad match that the
2896 deeper function found. Case 3: We found a bad match, and we're
2897 the deepest function. Then return what we found, even though
2898 it's a bad match. */
2899
2900 if (new_oload_champ != -1
2901 && classify_oload_match (new_oload_champ_bv, nargs, 0) == STANDARD)
2902 {
2903 *oload_syms = new_oload_syms;
2904 *oload_champ = new_oload_champ;
2905 *oload_champ_bv = new_oload_champ_bv;
2906 do_cleanups (old_cleanups);
2907 return 1;
2908 }
2909 else if (searched_deeper)
2910 {
2911 xfree (new_oload_syms);
2912 xfree (new_oload_champ_bv);
2913 discard_cleanups (old_cleanups);
2914 return 0;
2915 }
2916 else
2917 {
2918 *oload_syms = new_oload_syms;
2919 *oload_champ = new_oload_champ;
2920 *oload_champ_bv = new_oload_champ_bv;
2921 do_cleanups (old_cleanups);
2922 return 0;
2923 }
2924 }
2925
2926 /* Look for a function to take NARGS args of types ARG_TYPES. Find
2927 the best match from among the overloaded methods or functions
2928 (depending on METHOD) given by FNS_PTR or OLOAD_SYMS, respectively.
2929 The number of methods/functions in the list is given by NUM_FNS.
2930 Return the index of the best match; store an indication of the
2931 quality of the match in OLOAD_CHAMP_BV.
2932
2933 It is the caller's responsibility to free *OLOAD_CHAMP_BV. */
2934
2935 static int
2936 find_oload_champ (struct type **arg_types, int nargs, int method,
2937 int num_fns, struct fn_field *fns_ptr,
2938 struct symbol **oload_syms,
2939 struct badness_vector **oload_champ_bv)
2940 {
2941 int ix;
2942 /* A measure of how good an overloaded instance is. */
2943 struct badness_vector *bv;
2944 /* Index of best overloaded function. */
2945 int oload_champ = -1;
2946 /* Current ambiguity state for overload resolution. */
2947 int oload_ambiguous = 0;
2948 /* 0 => no ambiguity, 1 => two good funcs, 2 => incomparable funcs. */
2949
2950 *oload_champ_bv = NULL;
2951
2952 /* Consider each candidate in turn. */
2953 for (ix = 0; ix < num_fns; ix++)
2954 {
2955 int jj;
2956 int static_offset = oload_method_static (method, fns_ptr, ix);
2957 int nparms;
2958 struct type **parm_types;
2959
2960 if (method)
2961 {
2962 nparms = TYPE_NFIELDS (TYPE_FN_FIELD_TYPE (fns_ptr, ix));
2963 }
2964 else
2965 {
2966 /* If it's not a method, this is the proper place. */
2967 nparms = TYPE_NFIELDS (SYMBOL_TYPE (oload_syms[ix]));
2968 }
2969
2970 /* Prepare array of parameter types. */
2971 parm_types = (struct type **)
2972 xmalloc (nparms * (sizeof (struct type *)));
2973 for (jj = 0; jj < nparms; jj++)
2974 parm_types[jj] = (method
2975 ? (TYPE_FN_FIELD_ARGS (fns_ptr, ix)[jj].type)
2976 : TYPE_FIELD_TYPE (SYMBOL_TYPE (oload_syms[ix]),
2977 jj));
2978
2979 /* Compare parameter types to supplied argument types. Skip
2980 THIS for static methods. */
2981 bv = rank_function (parm_types, nparms,
2982 arg_types + static_offset,
2983 nargs - static_offset);
2984
2985 if (!*oload_champ_bv)
2986 {
2987 *oload_champ_bv = bv;
2988 oload_champ = 0;
2989 }
2990 else /* See whether current candidate is better or worse than
2991 previous best. */
2992 switch (compare_badness (bv, *oload_champ_bv))
2993 {
2994 case 0: /* Top two contenders are equally good. */
2995 oload_ambiguous = 1;
2996 break;
2997 case 1: /* Incomparable top contenders. */
2998 oload_ambiguous = 2;
2999 break;
3000 case 2: /* New champion, record details. */
3001 *oload_champ_bv = bv;
3002 oload_ambiguous = 0;
3003 oload_champ = ix;
3004 break;
3005 case 3:
3006 default:
3007 break;
3008 }
3009 xfree (parm_types);
3010 if (overload_debug)
3011 {
3012 if (method)
3013 fprintf_filtered (gdb_stderr,
3014 "Overloaded method instance %s, # of parms %d\n",
3015 fns_ptr[ix].physname, nparms);
3016 else
3017 fprintf_filtered (gdb_stderr,
3018 "Overloaded function instance "
3019 "%s # of parms %d\n",
3020 SYMBOL_DEMANGLED_NAME (oload_syms[ix]),
3021 nparms);
3022 for (jj = 0; jj < nargs - static_offset; jj++)
3023 fprintf_filtered (gdb_stderr,
3024 "...Badness @ %d : %d\n",
3025 jj, bv->rank[jj].rank);
3026 fprintf_filtered (gdb_stderr, "Overload resolution "
3027 "champion is %d, ambiguous? %d\n",
3028 oload_champ, oload_ambiguous);
3029 }
3030 }
3031
3032 return oload_champ;
3033 }
3034
3035 /* Return 1 if we're looking at a static method, 0 if we're looking at
3036 a non-static method or a function that isn't a method. */
3037
3038 static int
3039 oload_method_static (int method, struct fn_field *fns_ptr, int index)
3040 {
3041 if (method && fns_ptr && index >= 0
3042 && TYPE_FN_FIELD_STATIC_P (fns_ptr, index))
3043 return 1;
3044 else
3045 return 0;
3046 }
3047
3048 /* Check how good an overload match OLOAD_CHAMP_BV represents. */
3049
3050 static enum oload_classification
3051 classify_oload_match (struct badness_vector *oload_champ_bv,
3052 int nargs,
3053 int static_offset)
3054 {
3055 int ix;
3056
3057 for (ix = 1; ix <= nargs - static_offset; ix++)
3058 {
3059 /* If this conversion is as bad as INCOMPATIBLE_TYPE_BADNESS
3060 or worse return INCOMPATIBLE. */
3061 if (compare_ranks (oload_champ_bv->rank[ix],
3062 INCOMPATIBLE_TYPE_BADNESS) <= 0)
3063 return INCOMPATIBLE; /* Truly mismatched types. */
3064 /* Otherwise If this conversion is as bad as
3065 NS_POINTER_CONVERSION_BADNESS or worse return NON_STANDARD. */
3066 else if (compare_ranks (oload_champ_bv->rank[ix],
3067 NS_POINTER_CONVERSION_BADNESS) <= 0)
3068 return NON_STANDARD; /* Non-standard type conversions
3069 needed. */
3070 }
3071
3072 return STANDARD; /* Only standard conversions needed. */
3073 }
3074
3075 /* C++: return 1 is NAME is a legitimate name for the destructor of
3076 type TYPE. If TYPE does not have a destructor, or if NAME is
3077 inappropriate for TYPE, an error is signaled. */
3078 int
3079 destructor_name_p (const char *name, const struct type *type)
3080 {
3081 if (name[0] == '~')
3082 {
3083 char *dname = type_name_no_tag (type);
3084 char *cp = strchr (dname, '<');
3085 unsigned int len;
3086
3087 /* Do not compare the template part for template classes. */
3088 if (cp == NULL)
3089 len = strlen (dname);
3090 else
3091 len = cp - dname;
3092 if (strlen (name + 1) != len || strncmp (dname, name + 1, len) != 0)
3093 error (_("name of destructor must equal name of class"));
3094 else
3095 return 1;
3096 }
3097 return 0;
3098 }
3099
3100 /* Given TYPE, a structure/union,
3101 return 1 if the component named NAME from the ultimate target
3102 structure/union is defined, otherwise, return 0. */
3103
3104 int
3105 check_field (struct type *type, const char *name)
3106 {
3107 int i;
3108
3109 /* The type may be a stub. */
3110 CHECK_TYPEDEF (type);
3111
3112 for (i = TYPE_NFIELDS (type) - 1; i >= TYPE_N_BASECLASSES (type); i--)
3113 {
3114 char *t_field_name = TYPE_FIELD_NAME (type, i);
3115
3116 if (t_field_name && (strcmp_iw (t_field_name, name) == 0))
3117 return 1;
3118 }
3119
3120 /* C++: If it was not found as a data field, then try to return it
3121 as a pointer to a method. */
3122
3123 for (i = TYPE_NFN_FIELDS (type) - 1; i >= 0; --i)
3124 {
3125 if (strcmp_iw (TYPE_FN_FIELDLIST_NAME (type, i), name) == 0)
3126 return 1;
3127 }
3128
3129 for (i = TYPE_N_BASECLASSES (type) - 1; i >= 0; i--)
3130 if (check_field (TYPE_BASECLASS (type, i), name))
3131 return 1;
3132
3133 return 0;
3134 }
3135
3136 /* C++: Given an aggregate type CURTYPE, and a member name NAME,
3137 return the appropriate member (or the address of the member, if
3138 WANT_ADDRESS). This function is used to resolve user expressions
3139 of the form "DOMAIN::NAME". For more details on what happens, see
3140 the comment before value_struct_elt_for_reference. */
3141
3142 struct value *
3143 value_aggregate_elt (struct type *curtype, char *name,
3144 struct type *expect_type, int want_address,
3145 enum noside noside)
3146 {
3147 switch (TYPE_CODE (curtype))
3148 {
3149 case TYPE_CODE_STRUCT:
3150 case TYPE_CODE_UNION:
3151 return value_struct_elt_for_reference (curtype, 0, curtype,
3152 name, expect_type,
3153 want_address, noside);
3154 case TYPE_CODE_NAMESPACE:
3155 return value_namespace_elt (curtype, name,
3156 want_address, noside);
3157 default:
3158 internal_error (__FILE__, __LINE__,
3159 _("non-aggregate type in value_aggregate_elt"));
3160 }
3161 }
3162
3163 /* Compares the two method/function types T1 and T2 for "equality"
3164 with respect to the the methods' parameters. If the types of the
3165 two parameter lists are the same, returns 1; 0 otherwise. This
3166 comparison may ignore any artificial parameters in T1 if
3167 SKIP_ARTIFICIAL is non-zero. This function will ALWAYS skip
3168 the first artificial parameter in T1, assumed to be a 'this' pointer.
3169
3170 The type T2 is expected to have come from make_params (in eval.c). */
3171
3172 static int
3173 compare_parameters (struct type *t1, struct type *t2, int skip_artificial)
3174 {
3175 int start = 0;
3176
3177 if (TYPE_NFIELDS (t1) > 0 && TYPE_FIELD_ARTIFICIAL (t1, 0))
3178 ++start;
3179
3180 /* If skipping artificial fields, find the first real field
3181 in T1. */
3182 if (skip_artificial)
3183 {
3184 while (start < TYPE_NFIELDS (t1)
3185 && TYPE_FIELD_ARTIFICIAL (t1, start))
3186 ++start;
3187 }
3188
3189 /* Now compare parameters. */
3190
3191 /* Special case: a method taking void. T1 will contain no
3192 non-artificial fields, and T2 will contain TYPE_CODE_VOID. */
3193 if ((TYPE_NFIELDS (t1) - start) == 0 && TYPE_NFIELDS (t2) == 1
3194 && TYPE_CODE (TYPE_FIELD_TYPE (t2, 0)) == TYPE_CODE_VOID)
3195 return 1;
3196
3197 if ((TYPE_NFIELDS (t1) - start) == TYPE_NFIELDS (t2))
3198 {
3199 int i;
3200
3201 for (i = 0; i < TYPE_NFIELDS (t2); ++i)
3202 {
3203 if (compare_ranks (rank_one_type (TYPE_FIELD_TYPE (t1, start + i),
3204 TYPE_FIELD_TYPE (t2, i)),
3205 EXACT_MATCH_BADNESS) != 0)
3206 return 0;
3207 }
3208
3209 return 1;
3210 }
3211
3212 return 0;
3213 }
3214
3215 /* C++: Given an aggregate type CURTYPE, and a member name NAME,
3216 return the address of this member as a "pointer to member" type.
3217 If INTYPE is non-null, then it will be the type of the member we
3218 are looking for. This will help us resolve "pointers to member
3219 functions". This function is used to resolve user expressions of
3220 the form "DOMAIN::NAME". */
3221
3222 static struct value *
3223 value_struct_elt_for_reference (struct type *domain, int offset,
3224 struct type *curtype, char *name,
3225 struct type *intype,
3226 int want_address,
3227 enum noside noside)
3228 {
3229 struct type *t = curtype;
3230 int i;
3231 struct value *v, *result;
3232
3233 if (TYPE_CODE (t) != TYPE_CODE_STRUCT
3234 && TYPE_CODE (t) != TYPE_CODE_UNION)
3235 error (_("Internal error: non-aggregate type "
3236 "to value_struct_elt_for_reference"));
3237
3238 for (i = TYPE_NFIELDS (t) - 1; i >= TYPE_N_BASECLASSES (t); i--)
3239 {
3240 char *t_field_name = TYPE_FIELD_NAME (t, i);
3241
3242 if (t_field_name && strcmp (t_field_name, name) == 0)
3243 {
3244 if (field_is_static (&TYPE_FIELD (t, i)))
3245 {
3246 v = value_static_field (t, i);
3247 if (v == NULL)
3248 error (_("static field %s has been optimized out"),
3249 name);
3250 if (want_address)
3251 v = value_addr (v);
3252 return v;
3253 }
3254 if (TYPE_FIELD_PACKED (t, i))
3255 error (_("pointers to bitfield members not allowed"));
3256
3257 if (want_address)
3258 return value_from_longest
3259 (lookup_memberptr_type (TYPE_FIELD_TYPE (t, i), domain),
3260 offset + (LONGEST) (TYPE_FIELD_BITPOS (t, i) >> 3));
3261 else if (noside == EVAL_AVOID_SIDE_EFFECTS)
3262 return allocate_value (TYPE_FIELD_TYPE (t, i));
3263 else
3264 error (_("Cannot reference non-static field \"%s\""), name);
3265 }
3266 }
3267
3268 /* C++: If it was not found as a data field, then try to return it
3269 as a pointer to a method. */
3270
3271 /* Perform all necessary dereferencing. */
3272 while (intype && TYPE_CODE (intype) == TYPE_CODE_PTR)
3273 intype = TYPE_TARGET_TYPE (intype);
3274
3275 for (i = TYPE_NFN_FIELDS (t) - 1; i >= 0; --i)
3276 {
3277 char *t_field_name = TYPE_FN_FIELDLIST_NAME (t, i);
3278 char dem_opname[64];
3279
3280 if (strncmp (t_field_name, "__", 2) == 0
3281 || strncmp (t_field_name, "op", 2) == 0
3282 || strncmp (t_field_name, "type", 4) == 0)
3283 {
3284 if (cplus_demangle_opname (t_field_name,
3285 dem_opname, DMGL_ANSI))
3286 t_field_name = dem_opname;
3287 else if (cplus_demangle_opname (t_field_name,
3288 dem_opname, 0))
3289 t_field_name = dem_opname;
3290 }
3291 if (t_field_name && strcmp (t_field_name, name) == 0)
3292 {
3293 int j;
3294 int len = TYPE_FN_FIELDLIST_LENGTH (t, i);
3295 struct fn_field *f = TYPE_FN_FIELDLIST1 (t, i);
3296
3297 check_stub_method_group (t, i);
3298
3299 if (intype)
3300 {
3301 for (j = 0; j < len; ++j)
3302 {
3303 if (compare_parameters (TYPE_FN_FIELD_TYPE (f, j), intype, 0)
3304 || compare_parameters (TYPE_FN_FIELD_TYPE (f, j),
3305 intype, 1))
3306 break;
3307 }
3308
3309 if (j == len)
3310 error (_("no member function matches "
3311 "that type instantiation"));
3312 }
3313 else
3314 {
3315 int ii;
3316
3317 j = -1;
3318 for (ii = 0; ii < TYPE_FN_FIELDLIST_LENGTH (t, i);
3319 ++ii)
3320 {
3321 /* Skip artificial methods. This is necessary if,
3322 for example, the user wants to "print
3323 subclass::subclass" with only one user-defined
3324 constructor. There is no ambiguity in this
3325 case. */
3326 if (TYPE_FN_FIELD_ARTIFICIAL (f, ii))
3327 continue;
3328
3329 /* Desired method is ambiguous if more than one
3330 method is defined. */
3331 if (j != -1)
3332 error (_("non-unique member `%s' requires "
3333 "type instantiation"), name);
3334
3335 j = ii;
3336 }
3337 }
3338
3339 if (TYPE_FN_FIELD_STATIC_P (f, j))
3340 {
3341 struct symbol *s =
3342 lookup_symbol (TYPE_FN_FIELD_PHYSNAME (f, j),
3343 0, VAR_DOMAIN, 0);
3344
3345 if (s == NULL)
3346 return NULL;
3347
3348 if (want_address)
3349 return value_addr (read_var_value (s, 0));
3350 else
3351 return read_var_value (s, 0);
3352 }
3353
3354 if (TYPE_FN_FIELD_VIRTUAL_P (f, j))
3355 {
3356 if (want_address)
3357 {
3358 result = allocate_value
3359 (lookup_methodptr_type (TYPE_FN_FIELD_TYPE (f, j)));
3360 cplus_make_method_ptr (value_type (result),
3361 value_contents_writeable (result),
3362 TYPE_FN_FIELD_VOFFSET (f, j), 1);
3363 }
3364 else if (noside == EVAL_AVOID_SIDE_EFFECTS)
3365 return allocate_value (TYPE_FN_FIELD_TYPE (f, j));
3366 else
3367 error (_("Cannot reference virtual member function \"%s\""),
3368 name);
3369 }
3370 else
3371 {
3372 struct symbol *s =
3373 lookup_symbol (TYPE_FN_FIELD_PHYSNAME (f, j),
3374 0, VAR_DOMAIN, 0);
3375
3376 if (s == NULL)
3377 return NULL;
3378
3379 v = read_var_value (s, 0);
3380 if (!want_address)
3381 result = v;
3382 else
3383 {
3384 result = allocate_value (lookup_methodptr_type (TYPE_FN_FIELD_TYPE (f, j)));
3385 cplus_make_method_ptr (value_type (result),
3386 value_contents_writeable (result),
3387 value_address (v), 0);
3388 }
3389 }
3390 return result;
3391 }
3392 }
3393 for (i = TYPE_N_BASECLASSES (t) - 1; i >= 0; i--)
3394 {
3395 struct value *v;
3396 int base_offset;
3397
3398 if (BASETYPE_VIA_VIRTUAL (t, i))
3399 base_offset = 0;
3400 else
3401 base_offset = TYPE_BASECLASS_BITPOS (t, i) / 8;
3402 v = value_struct_elt_for_reference (domain,
3403 offset + base_offset,
3404 TYPE_BASECLASS (t, i),
3405 name, intype,
3406 want_address, noside);
3407 if (v)
3408 return v;
3409 }
3410
3411 /* As a last chance, pretend that CURTYPE is a namespace, and look
3412 it up that way; this (frequently) works for types nested inside
3413 classes. */
3414
3415 return value_maybe_namespace_elt (curtype, name,
3416 want_address, noside);
3417 }
3418
3419 /* C++: Return the member NAME of the namespace given by the type
3420 CURTYPE. */
3421
3422 static struct value *
3423 value_namespace_elt (const struct type *curtype,
3424 char *name, int want_address,
3425 enum noside noside)
3426 {
3427 struct value *retval = value_maybe_namespace_elt (curtype, name,
3428 want_address,
3429 noside);
3430
3431 if (retval == NULL)
3432 error (_("No symbol \"%s\" in namespace \"%s\"."),
3433 name, TYPE_TAG_NAME (curtype));
3434
3435 return retval;
3436 }
3437
3438 /* A helper function used by value_namespace_elt and
3439 value_struct_elt_for_reference. It looks up NAME inside the
3440 context CURTYPE; this works if CURTYPE is a namespace or if CURTYPE
3441 is a class and NAME refers to a type in CURTYPE itself (as opposed
3442 to, say, some base class of CURTYPE). */
3443
3444 static struct value *
3445 value_maybe_namespace_elt (const struct type *curtype,
3446 char *name, int want_address,
3447 enum noside noside)
3448 {
3449 const char *namespace_name = TYPE_TAG_NAME (curtype);
3450 struct symbol *sym;
3451 struct value *result;
3452
3453 sym = cp_lookup_symbol_namespace (namespace_name, name,
3454 get_selected_block (0), VAR_DOMAIN);
3455
3456 if (sym == NULL)
3457 {
3458 char *concatenated_name = alloca (strlen (namespace_name) + 2
3459 + strlen (name) + 1);
3460
3461 sprintf (concatenated_name, "%s::%s", namespace_name, name);
3462 sym = lookup_static_symbol_aux (concatenated_name, VAR_DOMAIN);
3463 }
3464
3465 if (sym == NULL)
3466 return NULL;
3467 else if ((noside == EVAL_AVOID_SIDE_EFFECTS)
3468 && (SYMBOL_CLASS (sym) == LOC_TYPEDEF))
3469 result = allocate_value (SYMBOL_TYPE (sym));
3470 else
3471 result = value_of_variable (sym, get_selected_block (0));
3472
3473 if (result && want_address)
3474 result = value_addr (result);
3475
3476 return result;
3477 }
3478
3479 /* Given a pointer value V, find the real (RTTI) type of the object it
3480 points to.
3481
3482 Other parameters FULL, TOP, USING_ENC as with value_rtti_type()
3483 and refer to the values computed for the object pointed to. */
3484
3485 struct type *
3486 value_rtti_target_type (struct value *v, int *full,
3487 int *top, int *using_enc)
3488 {
3489 struct value *target;
3490
3491 target = value_ind (v);
3492
3493 return value_rtti_type (target, full, top, using_enc);
3494 }
3495
3496 /* Given a value pointed to by ARGP, check its real run-time type, and
3497 if that is different from the enclosing type, create a new value
3498 using the real run-time type as the enclosing type (and of the same
3499 type as ARGP) and return it, with the embedded offset adjusted to
3500 be the correct offset to the enclosed object. RTYPE is the type,
3501 and XFULL, XTOP, and XUSING_ENC are the other parameters, computed
3502 by value_rtti_type(). If these are available, they can be supplied
3503 and a second call to value_rtti_type() is avoided. (Pass RTYPE ==
3504 NULL if they're not available. */
3505
3506 struct value *
3507 value_full_object (struct value *argp,
3508 struct type *rtype,
3509 int xfull, int xtop,
3510 int xusing_enc)
3511 {
3512 struct type *real_type;
3513 int full = 0;
3514 int top = -1;
3515 int using_enc = 0;
3516 struct value *new_val;
3517
3518 if (rtype)
3519 {
3520 real_type = rtype;
3521 full = xfull;
3522 top = xtop;
3523 using_enc = xusing_enc;
3524 }
3525 else
3526 real_type = value_rtti_type (argp, &full, &top, &using_enc);
3527
3528 /* If no RTTI data, or if object is already complete, do nothing. */
3529 if (!real_type || real_type == value_enclosing_type (argp))
3530 return argp;
3531
3532 /* If we have the full object, but for some reason the enclosing
3533 type is wrong, set it. */
3534 /* pai: FIXME -- sounds iffy */
3535 if (full)
3536 {
3537 argp = value_copy (argp);
3538 set_value_enclosing_type (argp, real_type);
3539 return argp;
3540 }
3541
3542 /* Check if object is in memory. */
3543 if (VALUE_LVAL (argp) != lval_memory)
3544 {
3545 warning (_("Couldn't retrieve complete object of RTTI "
3546 "type %s; object may be in register(s)."),
3547 TYPE_NAME (real_type));
3548
3549 return argp;
3550 }
3551
3552 /* All other cases -- retrieve the complete object. */
3553 /* Go back by the computed top_offset from the beginning of the
3554 object, adjusting for the embedded offset of argp if that's what
3555 value_rtti_type used for its computation. */
3556 new_val = value_at_lazy (real_type, value_address (argp) - top +
3557 (using_enc ? 0 : value_embedded_offset (argp)));
3558 deprecated_set_value_type (new_val, value_type (argp));
3559 set_value_embedded_offset (new_val, (using_enc
3560 ? top + value_embedded_offset (argp)
3561 : top));
3562 return new_val;
3563 }
3564
3565
3566 /* Return the value of the local variable, if one exists.
3567 Flag COMPLAIN signals an error if the request is made in an
3568 inappropriate context. */
3569
3570 struct value *
3571 value_of_local (const char *name, int complain)
3572 {
3573 struct symbol *func, *sym;
3574 struct block *b;
3575 struct value * ret;
3576 struct frame_info *frame;
3577
3578 if (complain)
3579 frame = get_selected_frame (_("no frame selected"));
3580 else
3581 {
3582 frame = deprecated_safe_get_selected_frame ();
3583 if (frame == 0)
3584 return 0;
3585 }
3586
3587 func = get_frame_function (frame);
3588 if (!func)
3589 {
3590 if (complain)
3591 error (_("no `%s' in nameless context"), name);
3592 else
3593 return 0;
3594 }
3595
3596 b = SYMBOL_BLOCK_VALUE (func);
3597 if (dict_empty (BLOCK_DICT (b)))
3598 {
3599 if (complain)
3600 error (_("no args, no `%s'"), name);
3601 else
3602 return 0;
3603 }
3604
3605 /* Calling lookup_block_symbol is necessary to get the LOC_REGISTER
3606 symbol instead of the LOC_ARG one (if both exist). */
3607 sym = lookup_block_symbol (b, name, VAR_DOMAIN);
3608 if (sym == NULL)
3609 {
3610 if (complain)
3611 error (_("current stack frame does not contain a variable named `%s'"),
3612 name);
3613 else
3614 return NULL;
3615 }
3616
3617 ret = read_var_value (sym, frame);
3618 if (ret == 0 && complain)
3619 error (_("`%s' argument unreadable"), name);
3620 return ret;
3621 }
3622
3623 /* C++/Objective-C: return the value of the class instance variable,
3624 if one exists. Flag COMPLAIN signals an error if the request is
3625 made in an inappropriate context. */
3626
3627 struct value *
3628 value_of_this (int complain)
3629 {
3630 if (!current_language->la_name_of_this)
3631 return 0;
3632 return value_of_local (current_language->la_name_of_this, complain);
3633 }
3634
3635 /* Create a slice (sub-string, sub-array) of ARRAY, that is LENGTH
3636 elements long, starting at LOWBOUND. The result has the same lower
3637 bound as the original ARRAY. */
3638
3639 struct value *
3640 value_slice (struct value *array, int lowbound, int length)
3641 {
3642 struct type *slice_range_type, *slice_type, *range_type;
3643 LONGEST lowerbound, upperbound;
3644 struct value *slice;
3645 struct type *array_type;
3646
3647 array_type = check_typedef (value_type (array));
3648 if (TYPE_CODE (array_type) != TYPE_CODE_ARRAY
3649 && TYPE_CODE (array_type) != TYPE_CODE_STRING
3650 && TYPE_CODE (array_type) != TYPE_CODE_BITSTRING)
3651 error (_("cannot take slice of non-array"));
3652
3653 range_type = TYPE_INDEX_TYPE (array_type);
3654 if (get_discrete_bounds (range_type, &lowerbound, &upperbound) < 0)
3655 error (_("slice from bad array or bitstring"));
3656
3657 if (lowbound < lowerbound || length < 0
3658 || lowbound + length - 1 > upperbound)
3659 error (_("slice out of range"));
3660
3661 /* FIXME-type-allocation: need a way to free this type when we are
3662 done with it. */
3663 slice_range_type = create_range_type ((struct type *) NULL,
3664 TYPE_TARGET_TYPE (range_type),
3665 lowbound,
3666 lowbound + length - 1);
3667 if (TYPE_CODE (array_type) == TYPE_CODE_BITSTRING)
3668 {
3669 int i;
3670
3671 slice_type = create_set_type ((struct type *) NULL,
3672 slice_range_type);
3673 TYPE_CODE (slice_type) = TYPE_CODE_BITSTRING;
3674 slice = value_zero (slice_type, not_lval);
3675
3676 for (i = 0; i < length; i++)
3677 {
3678 int element = value_bit_index (array_type,
3679 value_contents (array),
3680 lowbound + i);
3681
3682 if (element < 0)
3683 error (_("internal error accessing bitstring"));
3684 else if (element > 0)
3685 {
3686 int j = i % TARGET_CHAR_BIT;
3687
3688 if (gdbarch_bits_big_endian (get_type_arch (array_type)))
3689 j = TARGET_CHAR_BIT - 1 - j;
3690 value_contents_raw (slice)[i / TARGET_CHAR_BIT] |= (1 << j);
3691 }
3692 }
3693 /* We should set the address, bitssize, and bitspos, so the
3694 slice can be used on the LHS, but that may require extensions
3695 to value_assign. For now, just leave as a non_lval.
3696 FIXME. */
3697 }
3698 else
3699 {
3700 struct type *element_type = TYPE_TARGET_TYPE (array_type);
3701 LONGEST offset =
3702 (lowbound - lowerbound) * TYPE_LENGTH (check_typedef (element_type));
3703
3704 slice_type = create_array_type ((struct type *) NULL,
3705 element_type,
3706 slice_range_type);
3707 TYPE_CODE (slice_type) = TYPE_CODE (array_type);
3708
3709 if (VALUE_LVAL (array) == lval_memory && value_lazy (array))
3710 slice = allocate_value_lazy (slice_type);
3711 else
3712 {
3713 slice = allocate_value (slice_type);
3714 memcpy (value_contents_writeable (slice),
3715 value_contents (array) + offset,
3716 TYPE_LENGTH (slice_type));
3717 }
3718
3719 set_value_component_location (slice, array);
3720 VALUE_FRAME_ID (slice) = VALUE_FRAME_ID (array);
3721 set_value_offset (slice, value_offset (array) + offset);
3722 }
3723 return slice;
3724 }
3725
3726 /* Create a value for a FORTRAN complex number. Currently most of the
3727 time values are coerced to COMPLEX*16 (i.e. a complex number
3728 composed of 2 doubles. This really should be a smarter routine
3729 that figures out precision inteligently as opposed to assuming
3730 doubles. FIXME: fmb */
3731
3732 struct value *
3733 value_literal_complex (struct value *arg1,
3734 struct value *arg2,
3735 struct type *type)
3736 {
3737 struct value *val;
3738 struct type *real_type = TYPE_TARGET_TYPE (type);
3739
3740 val = allocate_value (type);
3741 arg1 = value_cast (real_type, arg1);
3742 arg2 = value_cast (real_type, arg2);
3743
3744 memcpy (value_contents_raw (val),
3745 value_contents (arg1), TYPE_LENGTH (real_type));
3746 memcpy (value_contents_raw (val) + TYPE_LENGTH (real_type),
3747 value_contents (arg2), TYPE_LENGTH (real_type));
3748 return val;
3749 }
3750
3751 /* Cast a value into the appropriate complex data type. */
3752
3753 static struct value *
3754 cast_into_complex (struct type *type, struct value *val)
3755 {
3756 struct type *real_type = TYPE_TARGET_TYPE (type);
3757
3758 if (TYPE_CODE (value_type (val)) == TYPE_CODE_COMPLEX)
3759 {
3760 struct type *val_real_type = TYPE_TARGET_TYPE (value_type (val));
3761 struct value *re_val = allocate_value (val_real_type);
3762 struct value *im_val = allocate_value (val_real_type);
3763
3764 memcpy (value_contents_raw (re_val),
3765 value_contents (val), TYPE_LENGTH (val_real_type));
3766 memcpy (value_contents_raw (im_val),
3767 value_contents (val) + TYPE_LENGTH (val_real_type),
3768 TYPE_LENGTH (val_real_type));
3769
3770 return value_literal_complex (re_val, im_val, type);
3771 }
3772 else if (TYPE_CODE (value_type (val)) == TYPE_CODE_FLT
3773 || TYPE_CODE (value_type (val)) == TYPE_CODE_INT)
3774 return value_literal_complex (val,
3775 value_zero (real_type, not_lval),
3776 type);
3777 else
3778 error (_("cannot cast non-number to complex"));
3779 }
3780
3781 void
3782 _initialize_valops (void)
3783 {
3784 add_setshow_boolean_cmd ("overload-resolution", class_support,
3785 &overload_resolution, _("\
3786 Set overload resolution in evaluating C++ functions."), _("\
3787 Show overload resolution in evaluating C++ functions."),
3788 NULL, NULL,
3789 show_overload_resolution,
3790 &setlist, &showlist);
3791 overload_resolution = 1;
3792 }
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