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