gdb/testsuite: Don't allow paths to appear in test name
[deliverable/binutils-gdb.git] / gdb / valops.c
1 /* Perform non-arithmetic operations on values, for GDB.
2
3 Copyright (C) 1986-2019 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 "observable.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 (gdb::array_view<value *> args,
58 const char *, const char *,
59 std::vector<symbol *> *oload_syms,
60 badness_vector *,
61 const int no_adl);
62
63 static int find_oload_champ_namespace_loop (gdb::array_view<value *> args,
64 const char *, const char *,
65 int, std::vector<symbol *> *oload_syms,
66 badness_vector *, int *,
67 const int no_adl);
68
69 static int find_oload_champ (gdb::array_view<value *> args,
70 size_t num_fns,
71 fn_field *methods,
72 xmethod_worker_up *xmethods,
73 symbol **functions,
74 badness_vector *oload_champ_bv);
75
76 static int oload_method_static_p (struct fn_field *, int);
77
78 enum oload_classification { STANDARD, NON_STANDARD, INCOMPATIBLE };
79
80 static enum oload_classification classify_oload_match
81 (const badness_vector &, 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 int overload_resolution = 0;
101 static void
102 show_overload_resolution (struct ui_file *file, int from_tty,
103 struct cmd_list_element *c,
104 const char *value)
105 {
106 fprintf_filtered (file, _("Overload resolution in evaluating "
107 "C++ functions is %s.\n"),
108 value);
109 }
110
111 /* Find the address of function name NAME in the inferior. If OBJF_P
112 is non-NULL, *OBJF_P will be set to the OBJFILE where the function
113 is defined. */
114
115 struct value *
116 find_function_in_inferior (const char *name, struct objfile **objf_p)
117 {
118 struct block_symbol sym;
119
120 sym = lookup_symbol (name, 0, VAR_DOMAIN, 0);
121 if (sym.symbol != NULL)
122 {
123 if (SYMBOL_CLASS (sym.symbol) != LOC_BLOCK)
124 {
125 error (_("\"%s\" exists in this program but is not a function."),
126 name);
127 }
128
129 if (objf_p)
130 *objf_p = symbol_objfile (sym.symbol);
131
132 return value_of_variable (sym.symbol, sym.block);
133 }
134 else
135 {
136 struct bound_minimal_symbol msymbol =
137 lookup_bound_minimal_symbol (name);
138
139 if (msymbol.minsym != NULL)
140 {
141 struct objfile *objfile = msymbol.objfile;
142 struct gdbarch *gdbarch = get_objfile_arch (objfile);
143
144 struct type *type;
145 CORE_ADDR maddr;
146 type = lookup_pointer_type (builtin_type (gdbarch)->builtin_char);
147 type = lookup_function_type (type);
148 type = lookup_pointer_type (type);
149 maddr = BMSYMBOL_VALUE_ADDRESS (msymbol);
150
151 if (objf_p)
152 *objf_p = objfile;
153
154 return value_from_pointer (type, maddr);
155 }
156 else
157 {
158 if (!target_has_execution)
159 error (_("evaluation of this expression "
160 "requires the target program to be active"));
161 else
162 error (_("evaluation of this expression requires the "
163 "program to have a function \"%s\"."),
164 name);
165 }
166 }
167 }
168
169 /* Allocate NBYTES of space in the inferior using the inferior's
170 malloc and return a value that is a pointer to the allocated
171 space. */
172
173 struct value *
174 value_allocate_space_in_inferior (int len)
175 {
176 struct objfile *objf;
177 struct value *val = find_function_in_inferior ("malloc", &objf);
178 struct gdbarch *gdbarch = get_objfile_arch (objf);
179 struct value *blocklen;
180
181 blocklen = value_from_longest (builtin_type (gdbarch)->builtin_int, len);
182 val = call_function_by_hand (val, NULL, blocklen);
183 if (value_logical_not (val))
184 {
185 if (!target_has_execution)
186 error (_("No memory available to program now: "
187 "you need to start the target first"));
188 else
189 error (_("No memory available to program: call to malloc failed"));
190 }
191 return val;
192 }
193
194 static CORE_ADDR
195 allocate_space_in_inferior (int len)
196 {
197 return value_as_long (value_allocate_space_in_inferior (len));
198 }
199
200 /* Cast struct value VAL to type TYPE and return as a value.
201 Both type and val must be of TYPE_CODE_STRUCT or TYPE_CODE_UNION
202 for this to work. Typedef to one of the codes is permitted.
203 Returns NULL if the cast is neither an upcast nor a downcast. */
204
205 static struct value *
206 value_cast_structs (struct type *type, struct value *v2)
207 {
208 struct type *t1;
209 struct type *t2;
210 struct value *v;
211
212 gdb_assert (type != NULL && v2 != NULL);
213
214 t1 = check_typedef (type);
215 t2 = check_typedef (value_type (v2));
216
217 /* Check preconditions. */
218 gdb_assert ((TYPE_CODE (t1) == TYPE_CODE_STRUCT
219 || TYPE_CODE (t1) == TYPE_CODE_UNION)
220 && !!"Precondition is that type is of STRUCT or UNION kind.");
221 gdb_assert ((TYPE_CODE (t2) == TYPE_CODE_STRUCT
222 || TYPE_CODE (t2) == TYPE_CODE_UNION)
223 && !!"Precondition is that value is of STRUCT or UNION kind");
224
225 if (TYPE_NAME (t1) != NULL
226 && TYPE_NAME (t2) != NULL
227 && !strcmp (TYPE_NAME (t1), TYPE_NAME (t2)))
228 return NULL;
229
230 /* Upcasting: look in the type of the source to see if it contains the
231 type of the target as a superclass. If so, we'll need to
232 offset the pointer rather than just change its type. */
233 if (TYPE_NAME (t1) != NULL)
234 {
235 v = search_struct_field (TYPE_NAME (t1),
236 v2, t2, 1);
237 if (v)
238 return v;
239 }
240
241 /* Downcasting: look in the type of the target to see if it contains the
242 type of the source as a superclass. If so, we'll need to
243 offset the pointer rather than just change its type. */
244 if (TYPE_NAME (t2) != NULL)
245 {
246 /* Try downcasting using the run-time type of the value. */
247 int full, using_enc;
248 LONGEST top;
249 struct type *real_type;
250
251 real_type = value_rtti_type (v2, &full, &top, &using_enc);
252 if (real_type)
253 {
254 v = value_full_object (v2, real_type, full, top, using_enc);
255 v = value_at_lazy (real_type, value_address (v));
256 real_type = value_type (v);
257
258 /* We might be trying to cast to the outermost enclosing
259 type, in which case search_struct_field won't work. */
260 if (TYPE_NAME (real_type) != NULL
261 && !strcmp (TYPE_NAME (real_type), TYPE_NAME (t1)))
262 return v;
263
264 v = search_struct_field (TYPE_NAME (t2), v, real_type, 1);
265 if (v)
266 return v;
267 }
268
269 /* Try downcasting using information from the destination type
270 T2. This wouldn't work properly for classes with virtual
271 bases, but those were handled above. */
272 v = search_struct_field (TYPE_NAME (t2),
273 value_zero (t1, not_lval), t1, 1);
274 if (v)
275 {
276 /* Downcasting is possible (t1 is superclass of v2). */
277 CORE_ADDR addr2 = value_address (v2);
278
279 addr2 -= value_address (v) + value_embedded_offset (v);
280 return value_at (type, addr2);
281 }
282 }
283
284 return NULL;
285 }
286
287 /* Cast one pointer or reference type to another. Both TYPE and
288 the type of ARG2 should be pointer types, or else both should be
289 reference types. If SUBCLASS_CHECK is non-zero, this will force a
290 check to see whether TYPE is a superclass of ARG2's type. If
291 SUBCLASS_CHECK is zero, then the subclass check is done only when
292 ARG2 is itself non-zero. Returns the new pointer or reference. */
293
294 struct value *
295 value_cast_pointers (struct type *type, struct value *arg2,
296 int subclass_check)
297 {
298 struct type *type1 = check_typedef (type);
299 struct type *type2 = check_typedef (value_type (arg2));
300 struct type *t1 = check_typedef (TYPE_TARGET_TYPE (type1));
301 struct type *t2 = check_typedef (TYPE_TARGET_TYPE (type2));
302
303 if (TYPE_CODE (t1) == TYPE_CODE_STRUCT
304 && TYPE_CODE (t2) == TYPE_CODE_STRUCT
305 && (subclass_check || !value_logical_not (arg2)))
306 {
307 struct value *v2;
308
309 if (TYPE_IS_REFERENCE (type2))
310 v2 = coerce_ref (arg2);
311 else
312 v2 = value_ind (arg2);
313 gdb_assert (TYPE_CODE (check_typedef (value_type (v2)))
314 == TYPE_CODE_STRUCT && !!"Why did coercion fail?");
315 v2 = value_cast_structs (t1, v2);
316 /* At this point we have what we can have, un-dereference if needed. */
317 if (v2)
318 {
319 struct value *v = value_addr (v2);
320
321 deprecated_set_value_type (v, type);
322 return v;
323 }
324 }
325
326 /* No superclass found, just change the pointer type. */
327 arg2 = value_copy (arg2);
328 deprecated_set_value_type (arg2, type);
329 set_value_enclosing_type (arg2, type);
330 set_value_pointed_to_offset (arg2, 0); /* pai: chk_val */
331 return arg2;
332 }
333
334 /* Cast value ARG2 to type TYPE and return as a value.
335 More general than a C cast: accepts any two types of the same length,
336 and if ARG2 is an lvalue it can be cast into anything at all. */
337 /* In C++, casts may change pointer or object representations. */
338
339 struct value *
340 value_cast (struct type *type, struct value *arg2)
341 {
342 enum type_code code1;
343 enum type_code code2;
344 int scalar;
345 struct type *type2;
346
347 int convert_to_boolean = 0;
348
349 if (value_type (arg2) == type)
350 return arg2;
351
352 /* Check if we are casting struct reference to struct reference. */
353 if (TYPE_IS_REFERENCE (check_typedef (type)))
354 {
355 /* We dereference type; then we recurse and finally
356 we generate value of the given reference. Nothing wrong with
357 that. */
358 struct type *t1 = check_typedef (type);
359 struct type *dereftype = check_typedef (TYPE_TARGET_TYPE (t1));
360 struct value *val = value_cast (dereftype, arg2);
361
362 return value_ref (val, TYPE_CODE (t1));
363 }
364
365 if (TYPE_IS_REFERENCE (check_typedef (value_type (arg2))))
366 /* We deref the value and then do the cast. */
367 return value_cast (type, coerce_ref (arg2));
368
369 /* Strip typedefs / resolve stubs in order to get at the type's
370 code/length, but remember the original type, to use as the
371 resulting type of the cast, in case it was a typedef. */
372 struct type *to_type = type;
373
374 type = check_typedef (type);
375 code1 = TYPE_CODE (type);
376 arg2 = coerce_ref (arg2);
377 type2 = check_typedef (value_type (arg2));
378
379 /* You can't cast to a reference type. See value_cast_pointers
380 instead. */
381 gdb_assert (!TYPE_IS_REFERENCE (type));
382
383 /* A cast to an undetermined-length array_type, such as
384 (TYPE [])OBJECT, is treated like a cast to (TYPE [N])OBJECT,
385 where N is sizeof(OBJECT)/sizeof(TYPE). */
386 if (code1 == TYPE_CODE_ARRAY)
387 {
388 struct type *element_type = TYPE_TARGET_TYPE (type);
389 unsigned element_length = TYPE_LENGTH (check_typedef (element_type));
390
391 if (element_length > 0 && TYPE_ARRAY_UPPER_BOUND_IS_UNDEFINED (type))
392 {
393 struct type *range_type = TYPE_INDEX_TYPE (type);
394 int val_length = TYPE_LENGTH (type2);
395 LONGEST low_bound, high_bound, new_length;
396
397 if (get_discrete_bounds (range_type, &low_bound, &high_bound) < 0)
398 low_bound = 0, high_bound = 0;
399 new_length = val_length / element_length;
400 if (val_length % element_length != 0)
401 warning (_("array element type size does not "
402 "divide object size in cast"));
403 /* FIXME-type-allocation: need a way to free this type when
404 we are done with it. */
405 range_type = create_static_range_type ((struct type *) NULL,
406 TYPE_TARGET_TYPE (range_type),
407 low_bound,
408 new_length + low_bound - 1);
409 deprecated_set_value_type (arg2,
410 create_array_type ((struct type *) NULL,
411 element_type,
412 range_type));
413 return arg2;
414 }
415 }
416
417 if (current_language->c_style_arrays
418 && TYPE_CODE (type2) == TYPE_CODE_ARRAY
419 && !TYPE_VECTOR (type2))
420 arg2 = value_coerce_array (arg2);
421
422 if (TYPE_CODE (type2) == TYPE_CODE_FUNC)
423 arg2 = value_coerce_function (arg2);
424
425 type2 = check_typedef (value_type (arg2));
426 code2 = TYPE_CODE (type2);
427
428 if (code1 == TYPE_CODE_COMPLEX)
429 return cast_into_complex (to_type, arg2);
430 if (code1 == TYPE_CODE_BOOL)
431 {
432 code1 = TYPE_CODE_INT;
433 convert_to_boolean = 1;
434 }
435 if (code1 == TYPE_CODE_CHAR)
436 code1 = TYPE_CODE_INT;
437 if (code2 == TYPE_CODE_BOOL || code2 == TYPE_CODE_CHAR)
438 code2 = TYPE_CODE_INT;
439
440 scalar = (code2 == TYPE_CODE_INT || code2 == TYPE_CODE_FLT
441 || code2 == TYPE_CODE_DECFLOAT || code2 == TYPE_CODE_ENUM
442 || code2 == TYPE_CODE_RANGE);
443
444 if ((code1 == TYPE_CODE_STRUCT || code1 == TYPE_CODE_UNION)
445 && (code2 == TYPE_CODE_STRUCT || code2 == TYPE_CODE_UNION)
446 && TYPE_NAME (type) != 0)
447 {
448 struct value *v = value_cast_structs (to_type, arg2);
449
450 if (v)
451 return v;
452 }
453
454 if (is_floating_type (type) && scalar)
455 {
456 if (is_floating_value (arg2))
457 {
458 struct value *v = allocate_value (to_type);
459 target_float_convert (value_contents (arg2), type2,
460 value_contents_raw (v), type);
461 return v;
462 }
463
464 /* The only option left is an integral type. */
465 if (TYPE_UNSIGNED (type2))
466 return value_from_ulongest (to_type, value_as_long (arg2));
467 else
468 return value_from_longest (to_type, value_as_long (arg2));
469 }
470 else if ((code1 == TYPE_CODE_INT || code1 == TYPE_CODE_ENUM
471 || code1 == TYPE_CODE_RANGE)
472 && (scalar || code2 == TYPE_CODE_PTR
473 || code2 == TYPE_CODE_MEMBERPTR))
474 {
475 LONGEST longest;
476
477 /* When we cast pointers to integers, we mustn't use
478 gdbarch_pointer_to_address to find the address the pointer
479 represents, as value_as_long would. GDB should evaluate
480 expressions just as the compiler would --- and the compiler
481 sees a cast as a simple reinterpretation of the pointer's
482 bits. */
483 if (code2 == TYPE_CODE_PTR)
484 longest = extract_unsigned_integer
485 (value_contents (arg2), TYPE_LENGTH (type2),
486 gdbarch_byte_order (get_type_arch (type2)));
487 else
488 longest = value_as_long (arg2);
489 return value_from_longest (to_type, convert_to_boolean ?
490 (LONGEST) (longest ? 1 : 0) : longest);
491 }
492 else if (code1 == TYPE_CODE_PTR && (code2 == TYPE_CODE_INT
493 || code2 == TYPE_CODE_ENUM
494 || code2 == TYPE_CODE_RANGE))
495 {
496 /* TYPE_LENGTH (type) is the length of a pointer, but we really
497 want the length of an address! -- we are really dealing with
498 addresses (i.e., gdb representations) not pointers (i.e.,
499 target representations) here.
500
501 This allows things like "print *(int *)0x01000234" to work
502 without printing a misleading message -- which would
503 otherwise occur when dealing with a target having two byte
504 pointers and four byte addresses. */
505
506 int addr_bit = gdbarch_addr_bit (get_type_arch (type2));
507 LONGEST longest = value_as_long (arg2);
508
509 if (addr_bit < sizeof (LONGEST) * HOST_CHAR_BIT)
510 {
511 if (longest >= ((LONGEST) 1 << addr_bit)
512 || longest <= -((LONGEST) 1 << addr_bit))
513 warning (_("value truncated"));
514 }
515 return value_from_longest (to_type, longest);
516 }
517 else if (code1 == TYPE_CODE_METHODPTR && code2 == TYPE_CODE_INT
518 && value_as_long (arg2) == 0)
519 {
520 struct value *result = allocate_value (to_type);
521
522 cplus_make_method_ptr (to_type, value_contents_writeable (result), 0, 0);
523 return result;
524 }
525 else if (code1 == TYPE_CODE_MEMBERPTR && code2 == TYPE_CODE_INT
526 && value_as_long (arg2) == 0)
527 {
528 /* The Itanium C++ ABI represents NULL pointers to members as
529 minus one, instead of biasing the normal case. */
530 return value_from_longest (to_type, -1);
531 }
532 else if (code1 == TYPE_CODE_ARRAY && TYPE_VECTOR (type)
533 && code2 == TYPE_CODE_ARRAY && TYPE_VECTOR (type2)
534 && TYPE_LENGTH (type) != TYPE_LENGTH (type2))
535 error (_("Cannot convert between vector values of different sizes"));
536 else if (code1 == TYPE_CODE_ARRAY && TYPE_VECTOR (type) && scalar
537 && TYPE_LENGTH (type) != TYPE_LENGTH (type2))
538 error (_("can only cast scalar to vector of same size"));
539 else if (code1 == TYPE_CODE_VOID)
540 {
541 return value_zero (to_type, not_lval);
542 }
543 else if (TYPE_LENGTH (type) == TYPE_LENGTH (type2))
544 {
545 if (code1 == TYPE_CODE_PTR && code2 == TYPE_CODE_PTR)
546 return value_cast_pointers (to_type, arg2, 0);
547
548 arg2 = value_copy (arg2);
549 deprecated_set_value_type (arg2, to_type);
550 set_value_enclosing_type (arg2, to_type);
551 set_value_pointed_to_offset (arg2, 0); /* pai: chk_val */
552 return arg2;
553 }
554 else if (VALUE_LVAL (arg2) == lval_memory)
555 return value_at_lazy (to_type, value_address (arg2));
556 else
557 {
558 error (_("Invalid cast."));
559 return 0;
560 }
561 }
562
563 /* The C++ reinterpret_cast operator. */
564
565 struct value *
566 value_reinterpret_cast (struct type *type, struct value *arg)
567 {
568 struct value *result;
569 struct type *real_type = check_typedef (type);
570 struct type *arg_type, *dest_type;
571 int is_ref = 0;
572 enum type_code dest_code, arg_code;
573
574 /* Do reference, function, and array conversion. */
575 arg = coerce_array (arg);
576
577 /* Attempt to preserve the type the user asked for. */
578 dest_type = type;
579
580 /* If we are casting to a reference type, transform
581 reinterpret_cast<T&[&]>(V) to *reinterpret_cast<T*>(&V). */
582 if (TYPE_IS_REFERENCE (real_type))
583 {
584 is_ref = 1;
585 arg = value_addr (arg);
586 dest_type = lookup_pointer_type (TYPE_TARGET_TYPE (dest_type));
587 real_type = lookup_pointer_type (real_type);
588 }
589
590 arg_type = value_type (arg);
591
592 dest_code = TYPE_CODE (real_type);
593 arg_code = TYPE_CODE (arg_type);
594
595 /* We can convert pointer types, or any pointer type to int, or int
596 type to pointer. */
597 if ((dest_code == TYPE_CODE_PTR && arg_code == TYPE_CODE_INT)
598 || (dest_code == TYPE_CODE_INT && arg_code == TYPE_CODE_PTR)
599 || (dest_code == TYPE_CODE_METHODPTR && arg_code == TYPE_CODE_INT)
600 || (dest_code == TYPE_CODE_INT && arg_code == TYPE_CODE_METHODPTR)
601 || (dest_code == TYPE_CODE_MEMBERPTR && arg_code == TYPE_CODE_INT)
602 || (dest_code == TYPE_CODE_INT && arg_code == TYPE_CODE_MEMBERPTR)
603 || (dest_code == arg_code
604 && (dest_code == TYPE_CODE_PTR
605 || dest_code == TYPE_CODE_METHODPTR
606 || dest_code == TYPE_CODE_MEMBERPTR)))
607 result = value_cast (dest_type, arg);
608 else
609 error (_("Invalid reinterpret_cast"));
610
611 if (is_ref)
612 result = value_cast (type, value_ref (value_ind (result),
613 TYPE_CODE (type)));
614
615 return result;
616 }
617
618 /* A helper for value_dynamic_cast. This implements the first of two
619 runtime checks: we iterate over all the base classes of the value's
620 class which are equal to the desired class; if only one of these
621 holds the value, then it is the answer. */
622
623 static int
624 dynamic_cast_check_1 (struct type *desired_type,
625 const gdb_byte *valaddr,
626 LONGEST embedded_offset,
627 CORE_ADDR address,
628 struct value *val,
629 struct type *search_type,
630 CORE_ADDR arg_addr,
631 struct type *arg_type,
632 struct value **result)
633 {
634 int i, result_count = 0;
635
636 for (i = 0; i < TYPE_N_BASECLASSES (search_type) && result_count < 2; ++i)
637 {
638 LONGEST offset = baseclass_offset (search_type, i, valaddr,
639 embedded_offset,
640 address, val);
641
642 if (class_types_same_p (desired_type, TYPE_BASECLASS (search_type, i)))
643 {
644 if (address + embedded_offset + offset >= arg_addr
645 && address + embedded_offset + offset < arg_addr + TYPE_LENGTH (arg_type))
646 {
647 ++result_count;
648 if (!*result)
649 *result = value_at_lazy (TYPE_BASECLASS (search_type, i),
650 address + embedded_offset + offset);
651 }
652 }
653 else
654 result_count += dynamic_cast_check_1 (desired_type,
655 valaddr,
656 embedded_offset + offset,
657 address, val,
658 TYPE_BASECLASS (search_type, i),
659 arg_addr,
660 arg_type,
661 result);
662 }
663
664 return result_count;
665 }
666
667 /* A helper for value_dynamic_cast. This implements the second of two
668 runtime checks: we look for a unique public sibling class of the
669 argument's declared class. */
670
671 static int
672 dynamic_cast_check_2 (struct type *desired_type,
673 const gdb_byte *valaddr,
674 LONGEST embedded_offset,
675 CORE_ADDR address,
676 struct value *val,
677 struct type *search_type,
678 struct value **result)
679 {
680 int i, result_count = 0;
681
682 for (i = 0; i < TYPE_N_BASECLASSES (search_type) && result_count < 2; ++i)
683 {
684 LONGEST offset;
685
686 if (! BASETYPE_VIA_PUBLIC (search_type, i))
687 continue;
688
689 offset = baseclass_offset (search_type, i, valaddr, embedded_offset,
690 address, val);
691 if (class_types_same_p (desired_type, TYPE_BASECLASS (search_type, i)))
692 {
693 ++result_count;
694 if (*result == NULL)
695 *result = value_at_lazy (TYPE_BASECLASS (search_type, i),
696 address + embedded_offset + offset);
697 }
698 else
699 result_count += dynamic_cast_check_2 (desired_type,
700 valaddr,
701 embedded_offset + offset,
702 address, val,
703 TYPE_BASECLASS (search_type, i),
704 result);
705 }
706
707 return result_count;
708 }
709
710 /* The C++ dynamic_cast operator. */
711
712 struct value *
713 value_dynamic_cast (struct type *type, struct value *arg)
714 {
715 int full, using_enc;
716 LONGEST top;
717 struct type *resolved_type = check_typedef (type);
718 struct type *arg_type = check_typedef (value_type (arg));
719 struct type *class_type, *rtti_type;
720 struct value *result, *tem, *original_arg = arg;
721 CORE_ADDR addr;
722 int is_ref = TYPE_IS_REFERENCE (resolved_type);
723
724 if (TYPE_CODE (resolved_type) != TYPE_CODE_PTR
725 && !TYPE_IS_REFERENCE (resolved_type))
726 error (_("Argument to dynamic_cast must be a pointer or reference type"));
727 if (TYPE_CODE (TYPE_TARGET_TYPE (resolved_type)) != TYPE_CODE_VOID
728 && TYPE_CODE (TYPE_TARGET_TYPE (resolved_type)) != TYPE_CODE_STRUCT)
729 error (_("Argument to dynamic_cast must be pointer to class or `void *'"));
730
731 class_type = check_typedef (TYPE_TARGET_TYPE (resolved_type));
732 if (TYPE_CODE (resolved_type) == TYPE_CODE_PTR)
733 {
734 if (TYPE_CODE (arg_type) != TYPE_CODE_PTR
735 && ! (TYPE_CODE (arg_type) == TYPE_CODE_INT
736 && value_as_long (arg) == 0))
737 error (_("Argument to dynamic_cast does not have pointer type"));
738 if (TYPE_CODE (arg_type) == TYPE_CODE_PTR)
739 {
740 arg_type = check_typedef (TYPE_TARGET_TYPE (arg_type));
741 if (TYPE_CODE (arg_type) != TYPE_CODE_STRUCT)
742 error (_("Argument to dynamic_cast does "
743 "not have pointer to class type"));
744 }
745
746 /* Handle NULL pointers. */
747 if (value_as_long (arg) == 0)
748 return value_zero (type, not_lval);
749
750 arg = value_ind (arg);
751 }
752 else
753 {
754 if (TYPE_CODE (arg_type) != TYPE_CODE_STRUCT)
755 error (_("Argument to dynamic_cast does not have class type"));
756 }
757
758 /* If the classes are the same, just return the argument. */
759 if (class_types_same_p (class_type, arg_type))
760 return value_cast (type, arg);
761
762 /* If the target type is a unique base class of the argument's
763 declared type, just cast it. */
764 if (is_ancestor (class_type, arg_type))
765 {
766 if (is_unique_ancestor (class_type, arg))
767 return value_cast (type, original_arg);
768 error (_("Ambiguous dynamic_cast"));
769 }
770
771 rtti_type = value_rtti_type (arg, &full, &top, &using_enc);
772 if (! rtti_type)
773 error (_("Couldn't determine value's most derived type for dynamic_cast"));
774
775 /* Compute the most derived object's address. */
776 addr = value_address (arg);
777 if (full)
778 {
779 /* Done. */
780 }
781 else if (using_enc)
782 addr += top;
783 else
784 addr += top + value_embedded_offset (arg);
785
786 /* dynamic_cast<void *> means to return a pointer to the
787 most-derived object. */
788 if (TYPE_CODE (resolved_type) == TYPE_CODE_PTR
789 && TYPE_CODE (TYPE_TARGET_TYPE (resolved_type)) == TYPE_CODE_VOID)
790 return value_at_lazy (type, addr);
791
792 tem = value_at (type, addr);
793 type = value_type (tem);
794
795 /* The first dynamic check specified in 5.2.7. */
796 if (is_public_ancestor (arg_type, TYPE_TARGET_TYPE (resolved_type)))
797 {
798 if (class_types_same_p (rtti_type, TYPE_TARGET_TYPE (resolved_type)))
799 return tem;
800 result = NULL;
801 if (dynamic_cast_check_1 (TYPE_TARGET_TYPE (resolved_type),
802 value_contents_for_printing (tem),
803 value_embedded_offset (tem),
804 value_address (tem), tem,
805 rtti_type, addr,
806 arg_type,
807 &result) == 1)
808 return value_cast (type,
809 is_ref
810 ? value_ref (result, TYPE_CODE (resolved_type))
811 : value_addr (result));
812 }
813
814 /* The second dynamic check specified in 5.2.7. */
815 result = NULL;
816 if (is_public_ancestor (arg_type, rtti_type)
817 && dynamic_cast_check_2 (TYPE_TARGET_TYPE (resolved_type),
818 value_contents_for_printing (tem),
819 value_embedded_offset (tem),
820 value_address (tem), tem,
821 rtti_type, &result) == 1)
822 return value_cast (type,
823 is_ref
824 ? value_ref (result, TYPE_CODE (resolved_type))
825 : value_addr (result));
826
827 if (TYPE_CODE (resolved_type) == TYPE_CODE_PTR)
828 return value_zero (type, not_lval);
829
830 error (_("dynamic_cast failed"));
831 }
832
833 /* Create a value of type TYPE that is zero, and return it. */
834
835 struct value *
836 value_zero (struct type *type, enum lval_type lv)
837 {
838 struct value *val = allocate_value (type);
839
840 VALUE_LVAL (val) = (lv == lval_computed ? not_lval : lv);
841 return val;
842 }
843
844 /* Create a not_lval value of numeric type TYPE that is one, and return it. */
845
846 struct value *
847 value_one (struct type *type)
848 {
849 struct type *type1 = check_typedef (type);
850 struct value *val;
851
852 if (is_integral_type (type1) || is_floating_type (type1))
853 {
854 val = value_from_longest (type, (LONGEST) 1);
855 }
856 else if (TYPE_CODE (type1) == TYPE_CODE_ARRAY && TYPE_VECTOR (type1))
857 {
858 struct type *eltype = check_typedef (TYPE_TARGET_TYPE (type1));
859 int i;
860 LONGEST low_bound, high_bound;
861 struct value *tmp;
862
863 if (!get_array_bounds (type1, &low_bound, &high_bound))
864 error (_("Could not determine the vector bounds"));
865
866 val = allocate_value (type);
867 for (i = 0; i < high_bound - low_bound + 1; i++)
868 {
869 tmp = value_one (eltype);
870 memcpy (value_contents_writeable (val) + i * TYPE_LENGTH (eltype),
871 value_contents_all (tmp), TYPE_LENGTH (eltype));
872 }
873 }
874 else
875 {
876 error (_("Not a numeric type."));
877 }
878
879 /* value_one result is never used for assignments to. */
880 gdb_assert (VALUE_LVAL (val) == not_lval);
881
882 return val;
883 }
884
885 /* Helper function for value_at, value_at_lazy, and value_at_lazy_stack.
886 The type of the created value may differ from the passed type TYPE.
887 Make sure to retrieve the returned values's new type after this call
888 e.g. in case the type is a variable length array. */
889
890 static struct value *
891 get_value_at (struct type *type, CORE_ADDR addr, int lazy)
892 {
893 struct value *val;
894
895 if (TYPE_CODE (check_typedef (type)) == TYPE_CODE_VOID)
896 error (_("Attempt to dereference a generic pointer."));
897
898 val = value_from_contents_and_address (type, NULL, addr);
899
900 if (!lazy)
901 value_fetch_lazy (val);
902
903 return val;
904 }
905
906 /* Return a value with type TYPE located at ADDR.
907
908 Call value_at only if the data needs to be fetched immediately;
909 if we can be 'lazy' and defer the fetch, perhaps indefinately, call
910 value_at_lazy instead. value_at_lazy simply records the address of
911 the data and sets the lazy-evaluation-required flag. The lazy flag
912 is tested in the value_contents macro, which is used if and when
913 the contents are actually required. The type of the created value
914 may differ from the passed type TYPE. Make sure to retrieve the
915 returned values's new type after this call e.g. in case the type
916 is a variable length array.
917
918 Note: value_at does *NOT* handle embedded offsets; perform such
919 adjustments before or after calling it. */
920
921 struct value *
922 value_at (struct type *type, CORE_ADDR addr)
923 {
924 return get_value_at (type, addr, 0);
925 }
926
927 /* Return a lazy value with type TYPE located at ADDR (cf. value_at).
928 The type of the created value may differ from the passed type TYPE.
929 Make sure to retrieve the returned values's new type after this call
930 e.g. in case the type is a variable length array. */
931
932 struct value *
933 value_at_lazy (struct type *type, CORE_ADDR addr)
934 {
935 return get_value_at (type, addr, 1);
936 }
937
938 void
939 read_value_memory (struct value *val, LONGEST bit_offset,
940 int stack, CORE_ADDR memaddr,
941 gdb_byte *buffer, size_t length)
942 {
943 ULONGEST xfered_total = 0;
944 struct gdbarch *arch = get_value_arch (val);
945 int unit_size = gdbarch_addressable_memory_unit_size (arch);
946 enum target_object object;
947
948 object = stack ? TARGET_OBJECT_STACK_MEMORY : TARGET_OBJECT_MEMORY;
949
950 while (xfered_total < length)
951 {
952 enum target_xfer_status status;
953 ULONGEST xfered_partial;
954
955 status = target_xfer_partial (current_top_target (),
956 object, NULL,
957 buffer + xfered_total * unit_size, NULL,
958 memaddr + xfered_total,
959 length - xfered_total,
960 &xfered_partial);
961
962 if (status == TARGET_XFER_OK)
963 /* nothing */;
964 else if (status == TARGET_XFER_UNAVAILABLE)
965 mark_value_bits_unavailable (val, (xfered_total * HOST_CHAR_BIT
966 + bit_offset),
967 xfered_partial * HOST_CHAR_BIT);
968 else if (status == TARGET_XFER_EOF)
969 memory_error (TARGET_XFER_E_IO, memaddr + xfered_total);
970 else
971 memory_error (status, memaddr + xfered_total);
972
973 xfered_total += xfered_partial;
974 QUIT;
975 }
976 }
977
978 /* Store the contents of FROMVAL into the location of TOVAL.
979 Return a new value with the location of TOVAL and contents of FROMVAL. */
980
981 struct value *
982 value_assign (struct value *toval, struct value *fromval)
983 {
984 struct type *type;
985 struct value *val;
986 struct frame_id old_frame;
987
988 if (!deprecated_value_modifiable (toval))
989 error (_("Left operand of assignment is not a modifiable lvalue."));
990
991 toval = coerce_ref (toval);
992
993 type = value_type (toval);
994 if (VALUE_LVAL (toval) != lval_internalvar)
995 fromval = value_cast (type, fromval);
996 else
997 {
998 /* Coerce arrays and functions to pointers, except for arrays
999 which only live in GDB's storage. */
1000 if (!value_must_coerce_to_target (fromval))
1001 fromval = coerce_array (fromval);
1002 }
1003
1004 type = check_typedef (type);
1005
1006 /* Since modifying a register can trash the frame chain, and
1007 modifying memory can trash the frame cache, we save the old frame
1008 and then restore the new frame afterwards. */
1009 old_frame = get_frame_id (deprecated_safe_get_selected_frame ());
1010
1011 switch (VALUE_LVAL (toval))
1012 {
1013 case lval_internalvar:
1014 set_internalvar (VALUE_INTERNALVAR (toval), fromval);
1015 return value_of_internalvar (get_type_arch (type),
1016 VALUE_INTERNALVAR (toval));
1017
1018 case lval_internalvar_component:
1019 {
1020 LONGEST offset = value_offset (toval);
1021
1022 /* Are we dealing with a bitfield?
1023
1024 It is important to mention that `value_parent (toval)' is
1025 non-NULL iff `value_bitsize (toval)' is non-zero. */
1026 if (value_bitsize (toval))
1027 {
1028 /* VALUE_INTERNALVAR below refers to the parent value, while
1029 the offset is relative to this parent value. */
1030 gdb_assert (value_parent (value_parent (toval)) == NULL);
1031 offset += value_offset (value_parent (toval));
1032 }
1033
1034 set_internalvar_component (VALUE_INTERNALVAR (toval),
1035 offset,
1036 value_bitpos (toval),
1037 value_bitsize (toval),
1038 fromval);
1039 }
1040 break;
1041
1042 case lval_memory:
1043 {
1044 const gdb_byte *dest_buffer;
1045 CORE_ADDR changed_addr;
1046 int changed_len;
1047 gdb_byte buffer[sizeof (LONGEST)];
1048
1049 if (value_bitsize (toval))
1050 {
1051 struct value *parent = value_parent (toval);
1052
1053 changed_addr = value_address (parent) + value_offset (toval);
1054 changed_len = (value_bitpos (toval)
1055 + value_bitsize (toval)
1056 + HOST_CHAR_BIT - 1)
1057 / HOST_CHAR_BIT;
1058
1059 /* If we can read-modify-write exactly the size of the
1060 containing type (e.g. short or int) then do so. This
1061 is safer for volatile bitfields mapped to hardware
1062 registers. */
1063 if (changed_len < TYPE_LENGTH (type)
1064 && TYPE_LENGTH (type) <= (int) sizeof (LONGEST)
1065 && ((LONGEST) changed_addr % TYPE_LENGTH (type)) == 0)
1066 changed_len = TYPE_LENGTH (type);
1067
1068 if (changed_len > (int) sizeof (LONGEST))
1069 error (_("Can't handle bitfields which "
1070 "don't fit in a %d bit word."),
1071 (int) sizeof (LONGEST) * HOST_CHAR_BIT);
1072
1073 read_memory (changed_addr, buffer, changed_len);
1074 modify_field (type, buffer, value_as_long (fromval),
1075 value_bitpos (toval), value_bitsize (toval));
1076 dest_buffer = buffer;
1077 }
1078 else
1079 {
1080 changed_addr = value_address (toval);
1081 changed_len = type_length_units (type);
1082 dest_buffer = value_contents (fromval);
1083 }
1084
1085 write_memory_with_notification (changed_addr, dest_buffer, changed_len);
1086 }
1087 break;
1088
1089 case lval_register:
1090 {
1091 struct frame_info *frame;
1092 struct gdbarch *gdbarch;
1093 int value_reg;
1094
1095 /* Figure out which frame this is in currently.
1096
1097 We use VALUE_FRAME_ID for obtaining the value's frame id instead of
1098 VALUE_NEXT_FRAME_ID due to requiring a frame which may be passed to
1099 put_frame_register_bytes() below. That function will (eventually)
1100 perform the necessary unwind operation by first obtaining the next
1101 frame. */
1102 frame = frame_find_by_id (VALUE_FRAME_ID (toval));
1103
1104 value_reg = VALUE_REGNUM (toval);
1105
1106 if (!frame)
1107 error (_("Value being assigned to is no longer active."));
1108
1109 gdbarch = get_frame_arch (frame);
1110
1111 if (value_bitsize (toval))
1112 {
1113 struct value *parent = value_parent (toval);
1114 LONGEST offset = value_offset (parent) + value_offset (toval);
1115 int changed_len;
1116 gdb_byte buffer[sizeof (LONGEST)];
1117 int optim, unavail;
1118
1119 changed_len = (value_bitpos (toval)
1120 + value_bitsize (toval)
1121 + HOST_CHAR_BIT - 1)
1122 / HOST_CHAR_BIT;
1123
1124 if (changed_len > (int) sizeof (LONGEST))
1125 error (_("Can't handle bitfields which "
1126 "don't fit in a %d bit word."),
1127 (int) sizeof (LONGEST) * HOST_CHAR_BIT);
1128
1129 if (!get_frame_register_bytes (frame, value_reg, offset,
1130 changed_len, buffer,
1131 &optim, &unavail))
1132 {
1133 if (optim)
1134 throw_error (OPTIMIZED_OUT_ERROR,
1135 _("value has been optimized out"));
1136 if (unavail)
1137 throw_error (NOT_AVAILABLE_ERROR,
1138 _("value is not available"));
1139 }
1140
1141 modify_field (type, buffer, value_as_long (fromval),
1142 value_bitpos (toval), value_bitsize (toval));
1143
1144 put_frame_register_bytes (frame, value_reg, offset,
1145 changed_len, buffer);
1146 }
1147 else
1148 {
1149 if (gdbarch_convert_register_p (gdbarch, VALUE_REGNUM (toval),
1150 type))
1151 {
1152 /* If TOVAL is a special machine register requiring
1153 conversion of program values to a special raw
1154 format. */
1155 gdbarch_value_to_register (gdbarch, frame,
1156 VALUE_REGNUM (toval), type,
1157 value_contents (fromval));
1158 }
1159 else
1160 {
1161 put_frame_register_bytes (frame, value_reg,
1162 value_offset (toval),
1163 TYPE_LENGTH (type),
1164 value_contents (fromval));
1165 }
1166 }
1167
1168 gdb::observers::register_changed.notify (frame, value_reg);
1169 break;
1170 }
1171
1172 case lval_computed:
1173 {
1174 const struct lval_funcs *funcs = value_computed_funcs (toval);
1175
1176 if (funcs->write != NULL)
1177 {
1178 funcs->write (toval, fromval);
1179 break;
1180 }
1181 }
1182 /* Fall through. */
1183
1184 default:
1185 error (_("Left operand of assignment is not an lvalue."));
1186 }
1187
1188 /* Assigning to the stack pointer, frame pointer, and other
1189 (architecture and calling convention specific) registers may
1190 cause the frame cache and regcache to be out of date. Assigning to memory
1191 also can. We just do this on all assignments to registers or
1192 memory, for simplicity's sake; I doubt the slowdown matters. */
1193 switch (VALUE_LVAL (toval))
1194 {
1195 case lval_memory:
1196 case lval_register:
1197 case lval_computed:
1198
1199 gdb::observers::target_changed.notify (current_top_target ());
1200
1201 /* Having destroyed the frame cache, restore the selected
1202 frame. */
1203
1204 /* FIXME: cagney/2002-11-02: There has to be a better way of
1205 doing this. Instead of constantly saving/restoring the
1206 frame. Why not create a get_selected_frame() function that,
1207 having saved the selected frame's ID can automatically
1208 re-find the previously selected frame automatically. */
1209
1210 {
1211 struct frame_info *fi = frame_find_by_id (old_frame);
1212
1213 if (fi != NULL)
1214 select_frame (fi);
1215 }
1216
1217 break;
1218 default:
1219 break;
1220 }
1221
1222 /* If the field does not entirely fill a LONGEST, then zero the sign
1223 bits. If the field is signed, and is negative, then sign
1224 extend. */
1225 if ((value_bitsize (toval) > 0)
1226 && (value_bitsize (toval) < 8 * (int) sizeof (LONGEST)))
1227 {
1228 LONGEST fieldval = value_as_long (fromval);
1229 LONGEST valmask = (((ULONGEST) 1) << value_bitsize (toval)) - 1;
1230
1231 fieldval &= valmask;
1232 if (!TYPE_UNSIGNED (type)
1233 && (fieldval & (valmask ^ (valmask >> 1))))
1234 fieldval |= ~valmask;
1235
1236 fromval = value_from_longest (type, fieldval);
1237 }
1238
1239 /* The return value is a copy of TOVAL so it shares its location
1240 information, but its contents are updated from FROMVAL. This
1241 implies the returned value is not lazy, even if TOVAL was. */
1242 val = value_copy (toval);
1243 set_value_lazy (val, 0);
1244 memcpy (value_contents_raw (val), value_contents (fromval),
1245 TYPE_LENGTH (type));
1246
1247 /* We copy over the enclosing type and pointed-to offset from FROMVAL
1248 in the case of pointer types. For object types, the enclosing type
1249 and embedded offset must *not* be copied: the target object refered
1250 to by TOVAL retains its original dynamic type after assignment. */
1251 if (TYPE_CODE (type) == TYPE_CODE_PTR)
1252 {
1253 set_value_enclosing_type (val, value_enclosing_type (fromval));
1254 set_value_pointed_to_offset (val, value_pointed_to_offset (fromval));
1255 }
1256
1257 return val;
1258 }
1259
1260 /* Extend a value VAL to COUNT repetitions of its type. */
1261
1262 struct value *
1263 value_repeat (struct value *arg1, int count)
1264 {
1265 struct value *val;
1266
1267 if (VALUE_LVAL (arg1) != lval_memory)
1268 error (_("Only values in memory can be extended with '@'."));
1269 if (count < 1)
1270 error (_("Invalid number %d of repetitions."), count);
1271
1272 val = allocate_repeat_value (value_enclosing_type (arg1), count);
1273
1274 VALUE_LVAL (val) = lval_memory;
1275 set_value_address (val, value_address (arg1));
1276
1277 read_value_memory (val, 0, value_stack (val), value_address (val),
1278 value_contents_all_raw (val),
1279 type_length_units (value_enclosing_type (val)));
1280
1281 return val;
1282 }
1283
1284 struct value *
1285 value_of_variable (struct symbol *var, const struct block *b)
1286 {
1287 struct frame_info *frame = NULL;
1288
1289 if (symbol_read_needs_frame (var))
1290 frame = get_selected_frame (_("No frame selected."));
1291
1292 return read_var_value (var, b, frame);
1293 }
1294
1295 struct value *
1296 address_of_variable (struct symbol *var, const struct block *b)
1297 {
1298 struct type *type = SYMBOL_TYPE (var);
1299 struct value *val;
1300
1301 /* Evaluate it first; if the result is a memory address, we're fine.
1302 Lazy evaluation pays off here. */
1303
1304 val = value_of_variable (var, b);
1305 type = value_type (val);
1306
1307 if ((VALUE_LVAL (val) == lval_memory && value_lazy (val))
1308 || TYPE_CODE (type) == TYPE_CODE_FUNC)
1309 {
1310 CORE_ADDR addr = value_address (val);
1311
1312 return value_from_pointer (lookup_pointer_type (type), addr);
1313 }
1314
1315 /* Not a memory address; check what the problem was. */
1316 switch (VALUE_LVAL (val))
1317 {
1318 case lval_register:
1319 {
1320 struct frame_info *frame;
1321 const char *regname;
1322
1323 frame = frame_find_by_id (VALUE_NEXT_FRAME_ID (val));
1324 gdb_assert (frame);
1325
1326 regname = gdbarch_register_name (get_frame_arch (frame),
1327 VALUE_REGNUM (val));
1328 gdb_assert (regname && *regname);
1329
1330 error (_("Address requested for identifier "
1331 "\"%s\" which is in register $%s"),
1332 SYMBOL_PRINT_NAME (var), regname);
1333 break;
1334 }
1335
1336 default:
1337 error (_("Can't take address of \"%s\" which isn't an lvalue."),
1338 SYMBOL_PRINT_NAME (var));
1339 break;
1340 }
1341
1342 return val;
1343 }
1344
1345 /* Return one if VAL does not live in target memory, but should in order
1346 to operate on it. Otherwise return zero. */
1347
1348 int
1349 value_must_coerce_to_target (struct value *val)
1350 {
1351 struct type *valtype;
1352
1353 /* The only lval kinds which do not live in target memory. */
1354 if (VALUE_LVAL (val) != not_lval
1355 && VALUE_LVAL (val) != lval_internalvar
1356 && VALUE_LVAL (val) != lval_xcallable)
1357 return 0;
1358
1359 valtype = check_typedef (value_type (val));
1360
1361 switch (TYPE_CODE (valtype))
1362 {
1363 case TYPE_CODE_ARRAY:
1364 return TYPE_VECTOR (valtype) ? 0 : 1;
1365 case TYPE_CODE_STRING:
1366 return 1;
1367 default:
1368 return 0;
1369 }
1370 }
1371
1372 /* Make sure that VAL lives in target memory if it's supposed to. For
1373 instance, strings are constructed as character arrays in GDB's
1374 storage, and this function copies them to the target. */
1375
1376 struct value *
1377 value_coerce_to_target (struct value *val)
1378 {
1379 LONGEST length;
1380 CORE_ADDR addr;
1381
1382 if (!value_must_coerce_to_target (val))
1383 return val;
1384
1385 length = TYPE_LENGTH (check_typedef (value_type (val)));
1386 addr = allocate_space_in_inferior (length);
1387 write_memory (addr, value_contents (val), length);
1388 return value_at_lazy (value_type (val), addr);
1389 }
1390
1391 /* Given a value which is an array, return a value which is a pointer
1392 to its first element, regardless of whether or not the array has a
1393 nonzero lower bound.
1394
1395 FIXME: A previous comment here indicated that this routine should
1396 be substracting the array's lower bound. It's not clear to me that
1397 this is correct. Given an array subscripting operation, it would
1398 certainly work to do the adjustment here, essentially computing:
1399
1400 (&array[0] - (lowerbound * sizeof array[0])) + (index * sizeof array[0])
1401
1402 However I believe a more appropriate and logical place to account
1403 for the lower bound is to do so in value_subscript, essentially
1404 computing:
1405
1406 (&array[0] + ((index - lowerbound) * sizeof array[0]))
1407
1408 As further evidence consider what would happen with operations
1409 other than array subscripting, where the caller would get back a
1410 value that had an address somewhere before the actual first element
1411 of the array, and the information about the lower bound would be
1412 lost because of the coercion to pointer type. */
1413
1414 struct value *
1415 value_coerce_array (struct value *arg1)
1416 {
1417 struct type *type = check_typedef (value_type (arg1));
1418
1419 /* If the user tries to do something requiring a pointer with an
1420 array that has not yet been pushed to the target, then this would
1421 be a good time to do so. */
1422 arg1 = value_coerce_to_target (arg1);
1423
1424 if (VALUE_LVAL (arg1) != lval_memory)
1425 error (_("Attempt to take address of value not located in memory."));
1426
1427 return value_from_pointer (lookup_pointer_type (TYPE_TARGET_TYPE (type)),
1428 value_address (arg1));
1429 }
1430
1431 /* Given a value which is a function, return a value which is a pointer
1432 to it. */
1433
1434 struct value *
1435 value_coerce_function (struct value *arg1)
1436 {
1437 struct value *retval;
1438
1439 if (VALUE_LVAL (arg1) != lval_memory)
1440 error (_("Attempt to take address of value not located in memory."));
1441
1442 retval = value_from_pointer (lookup_pointer_type (value_type (arg1)),
1443 value_address (arg1));
1444 return retval;
1445 }
1446
1447 /* Return a pointer value for the object for which ARG1 is the
1448 contents. */
1449
1450 struct value *
1451 value_addr (struct value *arg1)
1452 {
1453 struct value *arg2;
1454 struct type *type = check_typedef (value_type (arg1));
1455
1456 if (TYPE_IS_REFERENCE (type))
1457 {
1458 if (value_bits_synthetic_pointer (arg1, value_embedded_offset (arg1),
1459 TARGET_CHAR_BIT * TYPE_LENGTH (type)))
1460 arg1 = coerce_ref (arg1);
1461 else
1462 {
1463 /* Copy the value, but change the type from (T&) to (T*). We
1464 keep the same location information, which is efficient, and
1465 allows &(&X) to get the location containing the reference.
1466 Do the same to its enclosing type for consistency. */
1467 struct type *type_ptr
1468 = lookup_pointer_type (TYPE_TARGET_TYPE (type));
1469 struct type *enclosing_type
1470 = check_typedef (value_enclosing_type (arg1));
1471 struct type *enclosing_type_ptr
1472 = lookup_pointer_type (TYPE_TARGET_TYPE (enclosing_type));
1473
1474 arg2 = value_copy (arg1);
1475 deprecated_set_value_type (arg2, type_ptr);
1476 set_value_enclosing_type (arg2, enclosing_type_ptr);
1477
1478 return arg2;
1479 }
1480 }
1481 if (TYPE_CODE (type) == TYPE_CODE_FUNC)
1482 return value_coerce_function (arg1);
1483
1484 /* If this is an array that has not yet been pushed to the target,
1485 then this would be a good time to force it to memory. */
1486 arg1 = value_coerce_to_target (arg1);
1487
1488 if (VALUE_LVAL (arg1) != lval_memory)
1489 error (_("Attempt to take address of value not located in memory."));
1490
1491 /* Get target memory address. */
1492 arg2 = value_from_pointer (lookup_pointer_type (value_type (arg1)),
1493 (value_address (arg1)
1494 + value_embedded_offset (arg1)));
1495
1496 /* This may be a pointer to a base subobject; so remember the
1497 full derived object's type ... */
1498 set_value_enclosing_type (arg2,
1499 lookup_pointer_type (value_enclosing_type (arg1)));
1500 /* ... and also the relative position of the subobject in the full
1501 object. */
1502 set_value_pointed_to_offset (arg2, value_embedded_offset (arg1));
1503 return arg2;
1504 }
1505
1506 /* Return a reference value for the object for which ARG1 is the
1507 contents. */
1508
1509 struct value *
1510 value_ref (struct value *arg1, enum type_code refcode)
1511 {
1512 struct value *arg2;
1513 struct type *type = check_typedef (value_type (arg1));
1514
1515 gdb_assert (refcode == TYPE_CODE_REF || refcode == TYPE_CODE_RVALUE_REF);
1516
1517 if ((TYPE_CODE (type) == TYPE_CODE_REF
1518 || TYPE_CODE (type) == TYPE_CODE_RVALUE_REF)
1519 && TYPE_CODE (type) == refcode)
1520 return arg1;
1521
1522 arg2 = value_addr (arg1);
1523 deprecated_set_value_type (arg2, lookup_reference_type (type, refcode));
1524 return arg2;
1525 }
1526
1527 /* Given a value of a pointer type, apply the C unary * operator to
1528 it. */
1529
1530 struct value *
1531 value_ind (struct value *arg1)
1532 {
1533 struct type *base_type;
1534 struct value *arg2;
1535
1536 arg1 = coerce_array (arg1);
1537
1538 base_type = check_typedef (value_type (arg1));
1539
1540 if (VALUE_LVAL (arg1) == lval_computed)
1541 {
1542 const struct lval_funcs *funcs = value_computed_funcs (arg1);
1543
1544 if (funcs->indirect)
1545 {
1546 struct value *result = funcs->indirect (arg1);
1547
1548 if (result)
1549 return result;
1550 }
1551 }
1552
1553 if (TYPE_CODE (base_type) == TYPE_CODE_PTR)
1554 {
1555 struct type *enc_type;
1556
1557 /* We may be pointing to something embedded in a larger object.
1558 Get the real type of the enclosing object. */
1559 enc_type = check_typedef (value_enclosing_type (arg1));
1560 enc_type = TYPE_TARGET_TYPE (enc_type);
1561
1562 if (TYPE_CODE (check_typedef (enc_type)) == TYPE_CODE_FUNC
1563 || TYPE_CODE (check_typedef (enc_type)) == TYPE_CODE_METHOD)
1564 /* For functions, go through find_function_addr, which knows
1565 how to handle function descriptors. */
1566 arg2 = value_at_lazy (enc_type,
1567 find_function_addr (arg1, NULL));
1568 else
1569 /* Retrieve the enclosing object pointed to. */
1570 arg2 = value_at_lazy (enc_type,
1571 (value_as_address (arg1)
1572 - value_pointed_to_offset (arg1)));
1573
1574 enc_type = value_type (arg2);
1575 return readjust_indirect_value_type (arg2, enc_type, base_type, arg1);
1576 }
1577
1578 error (_("Attempt to take contents of a non-pointer value."));
1579 }
1580 \f
1581 /* Create a value for an array by allocating space in GDB, copying the
1582 data into that space, and then setting up an array value.
1583
1584 The array bounds are set from LOWBOUND and HIGHBOUND, and the array
1585 is populated from the values passed in ELEMVEC.
1586
1587 The element type of the array is inherited from the type of the
1588 first element, and all elements must have the same size (though we
1589 don't currently enforce any restriction on their types). */
1590
1591 struct value *
1592 value_array (int lowbound, int highbound, struct value **elemvec)
1593 {
1594 int nelem;
1595 int idx;
1596 ULONGEST typelength;
1597 struct value *val;
1598 struct type *arraytype;
1599
1600 /* Validate that the bounds are reasonable and that each of the
1601 elements have the same size. */
1602
1603 nelem = highbound - lowbound + 1;
1604 if (nelem <= 0)
1605 {
1606 error (_("bad array bounds (%d, %d)"), lowbound, highbound);
1607 }
1608 typelength = type_length_units (value_enclosing_type (elemvec[0]));
1609 for (idx = 1; idx < nelem; idx++)
1610 {
1611 if (type_length_units (value_enclosing_type (elemvec[idx]))
1612 != typelength)
1613 {
1614 error (_("array elements must all be the same size"));
1615 }
1616 }
1617
1618 arraytype = lookup_array_range_type (value_enclosing_type (elemvec[0]),
1619 lowbound, highbound);
1620
1621 if (!current_language->c_style_arrays)
1622 {
1623 val = allocate_value (arraytype);
1624 for (idx = 0; idx < nelem; idx++)
1625 value_contents_copy (val, idx * typelength, elemvec[idx], 0,
1626 typelength);
1627 return val;
1628 }
1629
1630 /* Allocate space to store the array, and then initialize it by
1631 copying in each element. */
1632
1633 val = allocate_value (arraytype);
1634 for (idx = 0; idx < nelem; idx++)
1635 value_contents_copy (val, idx * typelength, elemvec[idx], 0, typelength);
1636 return val;
1637 }
1638
1639 struct value *
1640 value_cstring (const char *ptr, ssize_t len, struct type *char_type)
1641 {
1642 struct value *val;
1643 int lowbound = current_language->string_lower_bound;
1644 ssize_t highbound = len / TYPE_LENGTH (char_type);
1645 struct type *stringtype
1646 = lookup_array_range_type (char_type, lowbound, highbound + lowbound - 1);
1647
1648 val = allocate_value (stringtype);
1649 memcpy (value_contents_raw (val), ptr, len);
1650 return val;
1651 }
1652
1653 /* Create a value for a string constant by allocating space in the
1654 inferior, copying the data into that space, and returning the
1655 address with type TYPE_CODE_STRING. PTR points to the string
1656 constant data; LEN is number of characters.
1657
1658 Note that string types are like array of char types with a lower
1659 bound of zero and an upper bound of LEN - 1. Also note that the
1660 string may contain embedded null bytes. */
1661
1662 struct value *
1663 value_string (const char *ptr, ssize_t len, struct type *char_type)
1664 {
1665 struct value *val;
1666 int lowbound = current_language->string_lower_bound;
1667 ssize_t highbound = len / TYPE_LENGTH (char_type);
1668 struct type *stringtype
1669 = lookup_string_range_type (char_type, lowbound, highbound + lowbound - 1);
1670
1671 val = allocate_value (stringtype);
1672 memcpy (value_contents_raw (val), ptr, len);
1673 return val;
1674 }
1675
1676 \f
1677 /* See if we can pass arguments in T2 to a function which takes
1678 arguments of types T1. T1 is a list of NARGS arguments, and T2 is
1679 a NULL-terminated vector. If some arguments need coercion of some
1680 sort, then the coerced values are written into T2. Return value is
1681 0 if the arguments could be matched, or the position at which they
1682 differ if not.
1683
1684 STATICP is nonzero if the T1 argument list came from a static
1685 member function. T2 will still include the ``this'' pointer, but
1686 it will be skipped.
1687
1688 For non-static member functions, we ignore the first argument,
1689 which is the type of the instance variable. This is because we
1690 want to handle calls with objects from derived classes. This is
1691 not entirely correct: we should actually check to make sure that a
1692 requested operation is type secure, shouldn't we? FIXME. */
1693
1694 static int
1695 typecmp (int staticp, int varargs, int nargs,
1696 struct field t1[], struct value *t2[])
1697 {
1698 int i;
1699
1700 if (t2 == 0)
1701 internal_error (__FILE__, __LINE__,
1702 _("typecmp: no argument list"));
1703
1704 /* Skip ``this'' argument if applicable. T2 will always include
1705 THIS. */
1706 if (staticp)
1707 t2 ++;
1708
1709 for (i = 0;
1710 (i < nargs) && TYPE_CODE (t1[i].type) != TYPE_CODE_VOID;
1711 i++)
1712 {
1713 struct type *tt1, *tt2;
1714
1715 if (!t2[i])
1716 return i + 1;
1717
1718 tt1 = check_typedef (t1[i].type);
1719 tt2 = check_typedef (value_type (t2[i]));
1720
1721 if (TYPE_IS_REFERENCE (tt1)
1722 /* We should be doing hairy argument matching, as below. */
1723 && (TYPE_CODE (check_typedef (TYPE_TARGET_TYPE (tt1)))
1724 == TYPE_CODE (tt2)))
1725 {
1726 if (TYPE_CODE (tt2) == TYPE_CODE_ARRAY)
1727 t2[i] = value_coerce_array (t2[i]);
1728 else
1729 t2[i] = value_ref (t2[i], TYPE_CODE (tt1));
1730 continue;
1731 }
1732
1733 /* djb - 20000715 - Until the new type structure is in the
1734 place, and we can attempt things like implicit conversions,
1735 we need to do this so you can take something like a map<const
1736 char *>, and properly access map["hello"], because the
1737 argument to [] will be a reference to a pointer to a char,
1738 and the argument will be a pointer to a char. */
1739 while (TYPE_IS_REFERENCE (tt1) || TYPE_CODE (tt1) == TYPE_CODE_PTR)
1740 {
1741 tt1 = check_typedef( TYPE_TARGET_TYPE(tt1) );
1742 }
1743 while (TYPE_CODE(tt2) == TYPE_CODE_ARRAY
1744 || TYPE_CODE(tt2) == TYPE_CODE_PTR
1745 || TYPE_IS_REFERENCE (tt2))
1746 {
1747 tt2 = check_typedef (TYPE_TARGET_TYPE(tt2));
1748 }
1749 if (TYPE_CODE (tt1) == TYPE_CODE (tt2))
1750 continue;
1751 /* Array to pointer is a `trivial conversion' according to the
1752 ARM. */
1753
1754 /* We should be doing much hairier argument matching (see
1755 section 13.2 of the ARM), but as a quick kludge, just check
1756 for the same type code. */
1757 if (TYPE_CODE (t1[i].type) != TYPE_CODE (value_type (t2[i])))
1758 return i + 1;
1759 }
1760 if (varargs || t2[i] == NULL)
1761 return 0;
1762 return i + 1;
1763 }
1764
1765 /* Helper class for do_search_struct_field that updates *RESULT_PTR
1766 and *LAST_BOFFSET, and possibly throws an exception if the field
1767 search has yielded ambiguous results. */
1768
1769 static void
1770 update_search_result (struct value **result_ptr, struct value *v,
1771 LONGEST *last_boffset, LONGEST boffset,
1772 const char *name, struct type *type)
1773 {
1774 if (v != NULL)
1775 {
1776 if (*result_ptr != NULL
1777 /* The result is not ambiguous if all the classes that are
1778 found occupy the same space. */
1779 && *last_boffset != boffset)
1780 error (_("base class '%s' is ambiguous in type '%s'"),
1781 name, TYPE_SAFE_NAME (type));
1782 *result_ptr = v;
1783 *last_boffset = boffset;
1784 }
1785 }
1786
1787 /* A helper for search_struct_field. This does all the work; most
1788 arguments are as passed to search_struct_field. The result is
1789 stored in *RESULT_PTR, which must be initialized to NULL.
1790 OUTERMOST_TYPE is the type of the initial type passed to
1791 search_struct_field; this is used for error reporting when the
1792 lookup is ambiguous. */
1793
1794 static void
1795 do_search_struct_field (const char *name, struct value *arg1, LONGEST offset,
1796 struct type *type, int looking_for_baseclass,
1797 struct value **result_ptr,
1798 LONGEST *last_boffset,
1799 struct type *outermost_type)
1800 {
1801 int i;
1802 int nbases;
1803
1804 type = check_typedef (type);
1805 nbases = TYPE_N_BASECLASSES (type);
1806
1807 if (!looking_for_baseclass)
1808 for (i = TYPE_NFIELDS (type) - 1; i >= nbases; i--)
1809 {
1810 const char *t_field_name = TYPE_FIELD_NAME (type, i);
1811
1812 if (t_field_name && (strcmp_iw (t_field_name, name) == 0))
1813 {
1814 struct value *v;
1815
1816 if (field_is_static (&TYPE_FIELD (type, i)))
1817 v = value_static_field (type, i);
1818 else
1819 v = value_primitive_field (arg1, offset, i, type);
1820 *result_ptr = v;
1821 return;
1822 }
1823
1824 if (t_field_name
1825 && t_field_name[0] == '\0')
1826 {
1827 struct type *field_type = TYPE_FIELD_TYPE (type, i);
1828
1829 if (TYPE_CODE (field_type) == TYPE_CODE_UNION
1830 || TYPE_CODE (field_type) == TYPE_CODE_STRUCT)
1831 {
1832 /* Look for a match through the fields of an anonymous
1833 union, or anonymous struct. C++ provides anonymous
1834 unions.
1835
1836 In the GNU Chill (now deleted from GDB)
1837 implementation of variant record types, each
1838 <alternative field> has an (anonymous) union type,
1839 each member of the union represents a <variant
1840 alternative>. Each <variant alternative> is
1841 represented as a struct, with a member for each
1842 <variant field>. */
1843
1844 struct value *v = NULL;
1845 LONGEST new_offset = offset;
1846
1847 /* This is pretty gross. In G++, the offset in an
1848 anonymous union is relative to the beginning of the
1849 enclosing struct. In the GNU Chill (now deleted
1850 from GDB) implementation of variant records, the
1851 bitpos is zero in an anonymous union field, so we
1852 have to add the offset of the union here. */
1853 if (TYPE_CODE (field_type) == TYPE_CODE_STRUCT
1854 || (TYPE_NFIELDS (field_type) > 0
1855 && TYPE_FIELD_BITPOS (field_type, 0) == 0))
1856 new_offset += TYPE_FIELD_BITPOS (type, i) / 8;
1857
1858 do_search_struct_field (name, arg1, new_offset,
1859 field_type,
1860 looking_for_baseclass, &v,
1861 last_boffset,
1862 outermost_type);
1863 if (v)
1864 {
1865 *result_ptr = v;
1866 return;
1867 }
1868 }
1869 }
1870 }
1871
1872 for (i = 0; i < nbases; i++)
1873 {
1874 struct value *v = NULL;
1875 struct type *basetype = check_typedef (TYPE_BASECLASS (type, i));
1876 /* If we are looking for baseclasses, this is what we get when
1877 we hit them. But it could happen that the base part's member
1878 name is not yet filled in. */
1879 int found_baseclass = (looking_for_baseclass
1880 && TYPE_BASECLASS_NAME (type, i) != NULL
1881 && (strcmp_iw (name,
1882 TYPE_BASECLASS_NAME (type,
1883 i)) == 0));
1884 LONGEST boffset = value_embedded_offset (arg1) + offset;
1885
1886 if (BASETYPE_VIA_VIRTUAL (type, i))
1887 {
1888 struct value *v2;
1889
1890 boffset = baseclass_offset (type, i,
1891 value_contents_for_printing (arg1),
1892 value_embedded_offset (arg1) + offset,
1893 value_address (arg1),
1894 arg1);
1895
1896 /* The virtual base class pointer might have been clobbered
1897 by the user program. Make sure that it still points to a
1898 valid memory location. */
1899
1900 boffset += value_embedded_offset (arg1) + offset;
1901 if (boffset < 0
1902 || boffset >= TYPE_LENGTH (value_enclosing_type (arg1)))
1903 {
1904 CORE_ADDR base_addr;
1905
1906 base_addr = value_address (arg1) + boffset;
1907 v2 = value_at_lazy (basetype, base_addr);
1908 if (target_read_memory (base_addr,
1909 value_contents_raw (v2),
1910 TYPE_LENGTH (value_type (v2))) != 0)
1911 error (_("virtual baseclass botch"));
1912 }
1913 else
1914 {
1915 v2 = value_copy (arg1);
1916 deprecated_set_value_type (v2, basetype);
1917 set_value_embedded_offset (v2, boffset);
1918 }
1919
1920 if (found_baseclass)
1921 v = v2;
1922 else
1923 {
1924 do_search_struct_field (name, v2, 0,
1925 TYPE_BASECLASS (type, i),
1926 looking_for_baseclass,
1927 result_ptr, last_boffset,
1928 outermost_type);
1929 }
1930 }
1931 else if (found_baseclass)
1932 v = value_primitive_field (arg1, offset, i, type);
1933 else
1934 {
1935 do_search_struct_field (name, arg1,
1936 offset + TYPE_BASECLASS_BITPOS (type,
1937 i) / 8,
1938 basetype, looking_for_baseclass,
1939 result_ptr, last_boffset,
1940 outermost_type);
1941 }
1942
1943 update_search_result (result_ptr, v, last_boffset,
1944 boffset, name, outermost_type);
1945 }
1946 }
1947
1948 /* Helper function used by value_struct_elt to recurse through
1949 baseclasses. Look for a field NAME in ARG1. Search in it assuming
1950 it has (class) type TYPE. If found, return value, else return NULL.
1951
1952 If LOOKING_FOR_BASECLASS, then instead of looking for struct
1953 fields, look for a baseclass named NAME. */
1954
1955 static struct value *
1956 search_struct_field (const char *name, struct value *arg1,
1957 struct type *type, int looking_for_baseclass)
1958 {
1959 struct value *result = NULL;
1960 LONGEST boffset = 0;
1961
1962 do_search_struct_field (name, arg1, 0, type, looking_for_baseclass,
1963 &result, &boffset, type);
1964 return result;
1965 }
1966
1967 /* Helper function used by value_struct_elt to recurse through
1968 baseclasses. Look for a field NAME in ARG1. Adjust the address of
1969 ARG1 by OFFSET bytes, and search in it assuming it has (class) type
1970 TYPE.
1971
1972 If found, return value, else if name matched and args not return
1973 (value) -1, else return NULL. */
1974
1975 static struct value *
1976 search_struct_method (const char *name, struct value **arg1p,
1977 struct value **args, LONGEST offset,
1978 int *static_memfuncp, struct type *type)
1979 {
1980 int i;
1981 struct value *v;
1982 int name_matched = 0;
1983
1984 type = check_typedef (type);
1985 for (i = TYPE_NFN_FIELDS (type) - 1; i >= 0; i--)
1986 {
1987 const char *t_field_name = TYPE_FN_FIELDLIST_NAME (type, i);
1988
1989 if (t_field_name && (strcmp_iw (t_field_name, name) == 0))
1990 {
1991 int j = TYPE_FN_FIELDLIST_LENGTH (type, i) - 1;
1992 struct fn_field *f = TYPE_FN_FIELDLIST1 (type, i);
1993
1994 name_matched = 1;
1995 check_stub_method_group (type, i);
1996 if (j > 0 && args == 0)
1997 error (_("cannot resolve overloaded method "
1998 "`%s': no arguments supplied"), name);
1999 else if (j == 0 && args == 0)
2000 {
2001 v = value_fn_field (arg1p, f, j, type, offset);
2002 if (v != NULL)
2003 return v;
2004 }
2005 else
2006 while (j >= 0)
2007 {
2008 if (!typecmp (TYPE_FN_FIELD_STATIC_P (f, j),
2009 TYPE_VARARGS (TYPE_FN_FIELD_TYPE (f, j)),
2010 TYPE_NFIELDS (TYPE_FN_FIELD_TYPE (f, j)),
2011 TYPE_FN_FIELD_ARGS (f, j), args))
2012 {
2013 if (TYPE_FN_FIELD_VIRTUAL_P (f, j))
2014 return value_virtual_fn_field (arg1p, f, j,
2015 type, offset);
2016 if (TYPE_FN_FIELD_STATIC_P (f, j)
2017 && static_memfuncp)
2018 *static_memfuncp = 1;
2019 v = value_fn_field (arg1p, f, j, type, offset);
2020 if (v != NULL)
2021 return v;
2022 }
2023 j--;
2024 }
2025 }
2026 }
2027
2028 for (i = TYPE_N_BASECLASSES (type) - 1; i >= 0; i--)
2029 {
2030 LONGEST base_offset;
2031 LONGEST this_offset;
2032
2033 if (BASETYPE_VIA_VIRTUAL (type, i))
2034 {
2035 struct type *baseclass = check_typedef (TYPE_BASECLASS (type, i));
2036 struct value *base_val;
2037 const gdb_byte *base_valaddr;
2038
2039 /* The virtual base class pointer might have been
2040 clobbered by the user program. Make sure that it
2041 still points to a valid memory location. */
2042
2043 if (offset < 0 || offset >= TYPE_LENGTH (type))
2044 {
2045 CORE_ADDR address;
2046
2047 gdb::byte_vector tmp (TYPE_LENGTH (baseclass));
2048 address = value_address (*arg1p);
2049
2050 if (target_read_memory (address + offset,
2051 tmp.data (), TYPE_LENGTH (baseclass)) != 0)
2052 error (_("virtual baseclass botch"));
2053
2054 base_val = value_from_contents_and_address (baseclass,
2055 tmp.data (),
2056 address + offset);
2057 base_valaddr = value_contents_for_printing (base_val);
2058 this_offset = 0;
2059 }
2060 else
2061 {
2062 base_val = *arg1p;
2063 base_valaddr = value_contents_for_printing (*arg1p);
2064 this_offset = offset;
2065 }
2066
2067 base_offset = baseclass_offset (type, i, base_valaddr,
2068 this_offset, value_address (base_val),
2069 base_val);
2070 }
2071 else
2072 {
2073 base_offset = TYPE_BASECLASS_BITPOS (type, i) / 8;
2074 }
2075 v = search_struct_method (name, arg1p, args, base_offset + offset,
2076 static_memfuncp, TYPE_BASECLASS (type, i));
2077 if (v == (struct value *) - 1)
2078 {
2079 name_matched = 1;
2080 }
2081 else if (v)
2082 {
2083 /* FIXME-bothner: Why is this commented out? Why is it here? */
2084 /* *arg1p = arg1_tmp; */
2085 return v;
2086 }
2087 }
2088 if (name_matched)
2089 return (struct value *) - 1;
2090 else
2091 return NULL;
2092 }
2093
2094 /* Given *ARGP, a value of type (pointer to a)* structure/union,
2095 extract the component named NAME from the ultimate target
2096 structure/union and return it as a value with its appropriate type.
2097 ERR is used in the error message if *ARGP's type is wrong.
2098
2099 C++: ARGS is a list of argument types to aid in the selection of
2100 an appropriate method. Also, handle derived types.
2101
2102 STATIC_MEMFUNCP, if non-NULL, points to a caller-supplied location
2103 where the truthvalue of whether the function that was resolved was
2104 a static member function or not is stored.
2105
2106 ERR is an error message to be printed in case the field is not
2107 found. */
2108
2109 struct value *
2110 value_struct_elt (struct value **argp, struct value **args,
2111 const char *name, int *static_memfuncp, const char *err)
2112 {
2113 struct type *t;
2114 struct value *v;
2115
2116 *argp = coerce_array (*argp);
2117
2118 t = check_typedef (value_type (*argp));
2119
2120 /* Follow pointers until we get to a non-pointer. */
2121
2122 while (TYPE_CODE (t) == TYPE_CODE_PTR || TYPE_IS_REFERENCE (t))
2123 {
2124 *argp = value_ind (*argp);
2125 /* Don't coerce fn pointer to fn and then back again! */
2126 if (TYPE_CODE (check_typedef (value_type (*argp))) != TYPE_CODE_FUNC)
2127 *argp = coerce_array (*argp);
2128 t = check_typedef (value_type (*argp));
2129 }
2130
2131 if (TYPE_CODE (t) != TYPE_CODE_STRUCT
2132 && TYPE_CODE (t) != TYPE_CODE_UNION)
2133 error (_("Attempt to extract a component of a value that is not a %s."),
2134 err);
2135
2136 /* Assume it's not, unless we see that it is. */
2137 if (static_memfuncp)
2138 *static_memfuncp = 0;
2139
2140 if (!args)
2141 {
2142 /* if there are no arguments ...do this... */
2143
2144 /* Try as a field first, because if we succeed, there is less
2145 work to be done. */
2146 v = search_struct_field (name, *argp, t, 0);
2147 if (v)
2148 return v;
2149
2150 /* C++: If it was not found as a data field, then try to
2151 return it as a pointer to a method. */
2152 v = search_struct_method (name, argp, args, 0,
2153 static_memfuncp, t);
2154
2155 if (v == (struct value *) - 1)
2156 error (_("Cannot take address of method %s."), name);
2157 else if (v == 0)
2158 {
2159 if (TYPE_NFN_FIELDS (t))
2160 error (_("There is no member or method named %s."), name);
2161 else
2162 error (_("There is no member named %s."), name);
2163 }
2164 return v;
2165 }
2166
2167 v = search_struct_method (name, argp, args, 0,
2168 static_memfuncp, t);
2169
2170 if (v == (struct value *) - 1)
2171 {
2172 error (_("One of the arguments you tried to pass to %s could not "
2173 "be converted to what the function wants."), name);
2174 }
2175 else if (v == 0)
2176 {
2177 /* See if user tried to invoke data as function. If so, hand it
2178 back. If it's not callable (i.e., a pointer to function),
2179 gdb should give an error. */
2180 v = search_struct_field (name, *argp, t, 0);
2181 /* If we found an ordinary field, then it is not a method call.
2182 So, treat it as if it were a static member function. */
2183 if (v && static_memfuncp)
2184 *static_memfuncp = 1;
2185 }
2186
2187 if (!v)
2188 throw_error (NOT_FOUND_ERROR,
2189 _("Structure has no component named %s."), name);
2190 return v;
2191 }
2192
2193 /* Given *ARGP, a value of type structure or union, or a pointer/reference
2194 to a structure or union, extract and return its component (field) of
2195 type FTYPE at the specified BITPOS.
2196 Throw an exception on error. */
2197
2198 struct value *
2199 value_struct_elt_bitpos (struct value **argp, int bitpos, struct type *ftype,
2200 const char *err)
2201 {
2202 struct type *t;
2203 int i;
2204
2205 *argp = coerce_array (*argp);
2206
2207 t = check_typedef (value_type (*argp));
2208
2209 while (TYPE_CODE (t) == TYPE_CODE_PTR || TYPE_IS_REFERENCE (t))
2210 {
2211 *argp = value_ind (*argp);
2212 if (TYPE_CODE (check_typedef (value_type (*argp))) != TYPE_CODE_FUNC)
2213 *argp = coerce_array (*argp);
2214 t = check_typedef (value_type (*argp));
2215 }
2216
2217 if (TYPE_CODE (t) != TYPE_CODE_STRUCT
2218 && TYPE_CODE (t) != TYPE_CODE_UNION)
2219 error (_("Attempt to extract a component of a value that is not a %s."),
2220 err);
2221
2222 for (i = TYPE_N_BASECLASSES (t); i < TYPE_NFIELDS (t); i++)
2223 {
2224 if (!field_is_static (&TYPE_FIELD (t, i))
2225 && bitpos == TYPE_FIELD_BITPOS (t, i)
2226 && types_equal (ftype, TYPE_FIELD_TYPE (t, i)))
2227 return value_primitive_field (*argp, 0, i, t);
2228 }
2229
2230 error (_("No field with matching bitpos and type."));
2231
2232 /* Never hit. */
2233 return NULL;
2234 }
2235
2236 /* See value.h. */
2237
2238 int
2239 value_union_variant (struct type *union_type, const gdb_byte *contents)
2240 {
2241 gdb_assert (TYPE_CODE (union_type) == TYPE_CODE_UNION
2242 && TYPE_FLAG_DISCRIMINATED_UNION (union_type));
2243
2244 struct dynamic_prop *discriminant_prop
2245 = get_dyn_prop (DYN_PROP_DISCRIMINATED, union_type);
2246 gdb_assert (discriminant_prop != nullptr);
2247
2248 struct discriminant_info *info
2249 = (struct discriminant_info *) discriminant_prop->data.baton;
2250 gdb_assert (info != nullptr);
2251
2252 /* If this is a univariant union, just return the sole field. */
2253 if (TYPE_NFIELDS (union_type) == 1)
2254 return 0;
2255 /* This should only happen for univariants, which we already dealt
2256 with. */
2257 gdb_assert (info->discriminant_index != -1);
2258
2259 /* Compute the discriminant. Note that unpack_field_as_long handles
2260 sign extension when necessary, as does the DWARF reader -- so
2261 signed discriminants will be handled correctly despite the use of
2262 an unsigned type here. */
2263 ULONGEST discriminant = unpack_field_as_long (union_type, contents,
2264 info->discriminant_index);
2265
2266 for (int i = 0; i < TYPE_NFIELDS (union_type); ++i)
2267 {
2268 if (i != info->default_index
2269 && i != info->discriminant_index
2270 && discriminant == info->discriminants[i])
2271 return i;
2272 }
2273
2274 if (info->default_index == -1)
2275 error (_("Could not find variant corresponding to discriminant %s"),
2276 pulongest (discriminant));
2277 return info->default_index;
2278 }
2279
2280 /* Search through the methods of an object (and its bases) to find a
2281 specified method. Return a reference to the fn_field list METHODS of
2282 overloaded instances defined in the source language. If available
2283 and matching, a vector of matching xmethods defined in extension
2284 languages are also returned in XMETHODS.
2285
2286 Helper function for value_find_oload_list.
2287 ARGP is a pointer to a pointer to a value (the object).
2288 METHOD is a string containing the method name.
2289 OFFSET is the offset within the value.
2290 TYPE is the assumed type of the object.
2291 METHODS is a pointer to the matching overloaded instances defined
2292 in the source language. Since this is a recursive function,
2293 *METHODS should be set to NULL when calling this function.
2294 NUM_FNS is the number of overloaded instances. *NUM_FNS should be set to
2295 0 when calling this function.
2296 XMETHODS is the vector of matching xmethod workers. *XMETHODS
2297 should also be set to NULL when calling this function.
2298 BASETYPE is set to the actual type of the subobject where the
2299 method is found.
2300 BOFFSET is the offset of the base subobject where the method is found. */
2301
2302 static void
2303 find_method_list (struct value **argp, const char *method,
2304 LONGEST offset, struct type *type,
2305 gdb::array_view<fn_field> *methods,
2306 std::vector<xmethod_worker_up> *xmethods,
2307 struct type **basetype, LONGEST *boffset)
2308 {
2309 int i;
2310 struct fn_field *f = NULL;
2311
2312 gdb_assert (methods != NULL && xmethods != NULL);
2313 type = check_typedef (type);
2314
2315 /* First check in object itself.
2316 This function is called recursively to search through base classes.
2317 If there is a source method match found at some stage, then we need not
2318 look for source methods in consequent recursive calls. */
2319 if (methods->empty ())
2320 {
2321 for (i = TYPE_NFN_FIELDS (type) - 1; i >= 0; i--)
2322 {
2323 /* pai: FIXME What about operators and type conversions? */
2324 const char *fn_field_name = TYPE_FN_FIELDLIST_NAME (type, i);
2325
2326 if (fn_field_name && (strcmp_iw (fn_field_name, method) == 0))
2327 {
2328 int len = TYPE_FN_FIELDLIST_LENGTH (type, i);
2329 f = TYPE_FN_FIELDLIST1 (type, i);
2330 *methods = gdb::make_array_view (f, len);
2331
2332 *basetype = type;
2333 *boffset = offset;
2334
2335 /* Resolve any stub methods. */
2336 check_stub_method_group (type, i);
2337
2338 break;
2339 }
2340 }
2341 }
2342
2343 /* Unlike source methods, xmethods can be accumulated over successive
2344 recursive calls. In other words, an xmethod named 'm' in a class
2345 will not hide an xmethod named 'm' in its base class(es). We want
2346 it to be this way because xmethods are after all convenience functions
2347 and hence there is no point restricting them with something like method
2348 hiding. Moreover, if hiding is done for xmethods as well, then we will
2349 have to provide a mechanism to un-hide (like the 'using' construct). */
2350 get_matching_xmethod_workers (type, method, xmethods);
2351
2352 /* If source methods are not found in current class, look for them in the
2353 base classes. We also have to go through the base classes to gather
2354 extension methods. */
2355 for (i = TYPE_N_BASECLASSES (type) - 1; i >= 0; i--)
2356 {
2357 LONGEST base_offset;
2358
2359 if (BASETYPE_VIA_VIRTUAL (type, i))
2360 {
2361 base_offset = baseclass_offset (type, i,
2362 value_contents_for_printing (*argp),
2363 value_offset (*argp) + offset,
2364 value_address (*argp), *argp);
2365 }
2366 else /* Non-virtual base, simply use bit position from debug
2367 info. */
2368 {
2369 base_offset = TYPE_BASECLASS_BITPOS (type, i) / 8;
2370 }
2371
2372 find_method_list (argp, method, base_offset + offset,
2373 TYPE_BASECLASS (type, i), methods,
2374 xmethods, basetype, boffset);
2375 }
2376 }
2377
2378 /* Return the list of overloaded methods of a specified name. The methods
2379 could be those GDB finds in the binary, or xmethod. Methods found in
2380 the binary are returned in METHODS, and xmethods are returned in
2381 XMETHODS.
2382
2383 ARGP is a pointer to a pointer to a value (the object).
2384 METHOD is the method name.
2385 OFFSET is the offset within the value contents.
2386 METHODS is the list of matching overloaded instances defined in
2387 the source language.
2388 XMETHODS is the vector of matching xmethod workers defined in
2389 extension languages.
2390 BASETYPE is set to the type of the base subobject that defines the
2391 method.
2392 BOFFSET is the offset of the base subobject which defines the method. */
2393
2394 static void
2395 value_find_oload_method_list (struct value **argp, const char *method,
2396 LONGEST offset,
2397 gdb::array_view<fn_field> *methods,
2398 std::vector<xmethod_worker_up> *xmethods,
2399 struct type **basetype, LONGEST *boffset)
2400 {
2401 struct type *t;
2402
2403 t = check_typedef (value_type (*argp));
2404
2405 /* Code snarfed from value_struct_elt. */
2406 while (TYPE_CODE (t) == TYPE_CODE_PTR || TYPE_IS_REFERENCE (t))
2407 {
2408 *argp = value_ind (*argp);
2409 /* Don't coerce fn pointer to fn and then back again! */
2410 if (TYPE_CODE (check_typedef (value_type (*argp))) != TYPE_CODE_FUNC)
2411 *argp = coerce_array (*argp);
2412 t = check_typedef (value_type (*argp));
2413 }
2414
2415 if (TYPE_CODE (t) != TYPE_CODE_STRUCT
2416 && TYPE_CODE (t) != TYPE_CODE_UNION)
2417 error (_("Attempt to extract a component of a "
2418 "value that is not a struct or union"));
2419
2420 gdb_assert (methods != NULL && xmethods != NULL);
2421
2422 /* Clear the lists. */
2423 *methods = {};
2424 xmethods->clear ();
2425
2426 find_method_list (argp, method, 0, t, methods, xmethods,
2427 basetype, boffset);
2428 }
2429
2430 /* Given an array of arguments (ARGS) (which includes an entry for
2431 "this" in the case of C++ methods), the NAME of a function, and
2432 whether it's a method or not (METHOD), find the best function that
2433 matches on the argument types according to the overload resolution
2434 rules.
2435
2436 METHOD can be one of three values:
2437 NON_METHOD for non-member functions.
2438 METHOD: for member functions.
2439 BOTH: used for overload resolution of operators where the
2440 candidates are expected to be either member or non member
2441 functions. In this case the first argument ARGTYPES
2442 (representing 'this') is expected to be a reference to the
2443 target object, and will be dereferenced when attempting the
2444 non-member search.
2445
2446 In the case of class methods, the parameter OBJ is an object value
2447 in which to search for overloaded methods.
2448
2449 In the case of non-method functions, the parameter FSYM is a symbol
2450 corresponding to one of the overloaded functions.
2451
2452 Return value is an integer: 0 -> good match, 10 -> debugger applied
2453 non-standard coercions, 100 -> incompatible.
2454
2455 If a method is being searched for, VALP will hold the value.
2456 If a non-method is being searched for, SYMP will hold the symbol
2457 for it.
2458
2459 If a method is being searched for, and it is a static method,
2460 then STATICP will point to a non-zero value.
2461
2462 If NO_ADL argument dependent lookup is disabled. This is used to prevent
2463 ADL overload candidates when performing overload resolution for a fully
2464 qualified name.
2465
2466 If NOSIDE is EVAL_AVOID_SIDE_EFFECTS, then OBJP's memory cannot be
2467 read while picking the best overload match (it may be all zeroes and thus
2468 not have a vtable pointer), in which case skip virtual function lookup.
2469 This is ok as typically EVAL_AVOID_SIDE_EFFECTS is only used to determine
2470 the result type.
2471
2472 Note: This function does *not* check the value of
2473 overload_resolution. Caller must check it to see whether overload
2474 resolution is permitted. */
2475
2476 int
2477 find_overload_match (gdb::array_view<value *> args,
2478 const char *name, enum oload_search_type method,
2479 struct value **objp, struct symbol *fsym,
2480 struct value **valp, struct symbol **symp,
2481 int *staticp, const int no_adl,
2482 const enum noside noside)
2483 {
2484 struct value *obj = (objp ? *objp : NULL);
2485 struct type *obj_type = obj ? value_type (obj) : NULL;
2486 /* Index of best overloaded function. */
2487 int func_oload_champ = -1;
2488 int method_oload_champ = -1;
2489 int src_method_oload_champ = -1;
2490 int ext_method_oload_champ = -1;
2491
2492 /* The measure for the current best match. */
2493 badness_vector method_badness;
2494 badness_vector func_badness;
2495 badness_vector ext_method_badness;
2496 badness_vector src_method_badness;
2497
2498 struct value *temp = obj;
2499 /* For methods, the list of overloaded methods. */
2500 gdb::array_view<fn_field> methods;
2501 /* For non-methods, the list of overloaded function symbols. */
2502 std::vector<symbol *> functions;
2503 /* For xmethods, the vector of xmethod workers. */
2504 std::vector<xmethod_worker_up> xmethods;
2505 struct type *basetype = NULL;
2506 LONGEST boffset;
2507
2508 const char *obj_type_name = NULL;
2509 const char *func_name = NULL;
2510 gdb::unique_xmalloc_ptr<char> temp_func;
2511 enum oload_classification match_quality;
2512 enum oload_classification method_match_quality = INCOMPATIBLE;
2513 enum oload_classification src_method_match_quality = INCOMPATIBLE;
2514 enum oload_classification ext_method_match_quality = INCOMPATIBLE;
2515 enum oload_classification func_match_quality = INCOMPATIBLE;
2516
2517 /* Get the list of overloaded methods or functions. */
2518 if (method == METHOD || method == BOTH)
2519 {
2520 gdb_assert (obj);
2521
2522 /* OBJ may be a pointer value rather than the object itself. */
2523 obj = coerce_ref (obj);
2524 while (TYPE_CODE (check_typedef (value_type (obj))) == TYPE_CODE_PTR)
2525 obj = coerce_ref (value_ind (obj));
2526 obj_type_name = TYPE_NAME (value_type (obj));
2527
2528 /* First check whether this is a data member, e.g. a pointer to
2529 a function. */
2530 if (TYPE_CODE (check_typedef (value_type (obj))) == TYPE_CODE_STRUCT)
2531 {
2532 *valp = search_struct_field (name, obj,
2533 check_typedef (value_type (obj)), 0);
2534 if (*valp)
2535 {
2536 *staticp = 1;
2537 return 0;
2538 }
2539 }
2540
2541 /* Retrieve the list of methods with the name NAME. */
2542 value_find_oload_method_list (&temp, name, 0, &methods,
2543 &xmethods, &basetype, &boffset);
2544 /* If this is a method only search, and no methods were found
2545 the search has failed. */
2546 if (method == METHOD && methods.empty () && xmethods.empty ())
2547 error (_("Couldn't find method %s%s%s"),
2548 obj_type_name,
2549 (obj_type_name && *obj_type_name) ? "::" : "",
2550 name);
2551 /* If we are dealing with stub method types, they should have
2552 been resolved by find_method_list via
2553 value_find_oload_method_list above. */
2554 if (!methods.empty ())
2555 {
2556 gdb_assert (TYPE_SELF_TYPE (methods[0].type) != NULL);
2557
2558 src_method_oload_champ
2559 = find_oload_champ (args,
2560 methods.size (),
2561 methods.data (), NULL, NULL,
2562 &src_method_badness);
2563
2564 src_method_match_quality = classify_oload_match
2565 (src_method_badness, args.size (),
2566 oload_method_static_p (methods.data (), src_method_oload_champ));
2567 }
2568
2569 if (!xmethods.empty ())
2570 {
2571 ext_method_oload_champ
2572 = find_oload_champ (args,
2573 xmethods.size (),
2574 NULL, xmethods.data (), NULL,
2575 &ext_method_badness);
2576 ext_method_match_quality = classify_oload_match (ext_method_badness,
2577 args.size (), 0);
2578 }
2579
2580 if (src_method_oload_champ >= 0 && ext_method_oload_champ >= 0)
2581 {
2582 switch (compare_badness (ext_method_badness, src_method_badness))
2583 {
2584 case 0: /* Src method and xmethod are equally good. */
2585 /* If src method and xmethod are equally good, then
2586 xmethod should be the winner. Hence, fall through to the
2587 case where a xmethod is better than the source
2588 method, except when the xmethod match quality is
2589 non-standard. */
2590 /* FALLTHROUGH */
2591 case 1: /* Src method and ext method are incompatible. */
2592 /* If ext method match is not standard, then let source method
2593 win. Otherwise, fallthrough to let xmethod win. */
2594 if (ext_method_match_quality != STANDARD)
2595 {
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 }
2602 /* FALLTHROUGH */
2603 case 2: /* Ext method is champion. */
2604 method_oload_champ = ext_method_oload_champ;
2605 method_badness = ext_method_badness;
2606 src_method_oload_champ = -1;
2607 method_match_quality = ext_method_match_quality;
2608 break;
2609 case 3: /* Src method is champion. */
2610 method_oload_champ = src_method_oload_champ;
2611 method_badness = src_method_badness;
2612 ext_method_oload_champ = -1;
2613 method_match_quality = src_method_match_quality;
2614 break;
2615 default:
2616 gdb_assert_not_reached ("Unexpected overload comparison "
2617 "result");
2618 break;
2619 }
2620 }
2621 else if (src_method_oload_champ >= 0)
2622 {
2623 method_oload_champ = src_method_oload_champ;
2624 method_badness = src_method_badness;
2625 method_match_quality = src_method_match_quality;
2626 }
2627 else if (ext_method_oload_champ >= 0)
2628 {
2629 method_oload_champ = ext_method_oload_champ;
2630 method_badness = ext_method_badness;
2631 method_match_quality = ext_method_match_quality;
2632 }
2633 }
2634
2635 if (method == NON_METHOD || method == BOTH)
2636 {
2637 const char *qualified_name = NULL;
2638
2639 /* If the overload match is being search for both as a method
2640 and non member function, the first argument must now be
2641 dereferenced. */
2642 if (method == BOTH)
2643 args[0] = value_ind (args[0]);
2644
2645 if (fsym)
2646 {
2647 qualified_name = SYMBOL_NATURAL_NAME (fsym);
2648
2649 /* If we have a function with a C++ name, try to extract just
2650 the function part. Do not try this for non-functions (e.g.
2651 function pointers). */
2652 if (qualified_name
2653 && TYPE_CODE (check_typedef (SYMBOL_TYPE (fsym)))
2654 == TYPE_CODE_FUNC)
2655 {
2656 temp_func = cp_func_name (qualified_name);
2657
2658 /* If cp_func_name did not remove anything, the name of the
2659 symbol did not include scope or argument types - it was
2660 probably a C-style function. */
2661 if (temp_func != nullptr)
2662 {
2663 if (strcmp (temp_func.get (), qualified_name) == 0)
2664 func_name = NULL;
2665 else
2666 func_name = temp_func.get ();
2667 }
2668 }
2669 }
2670 else
2671 {
2672 func_name = name;
2673 qualified_name = name;
2674 }
2675
2676 /* If there was no C++ name, this must be a C-style function or
2677 not a function at all. Just return the same symbol. Do the
2678 same if cp_func_name fails for some reason. */
2679 if (func_name == NULL)
2680 {
2681 *symp = fsym;
2682 return 0;
2683 }
2684
2685 func_oload_champ = find_oload_champ_namespace (args,
2686 func_name,
2687 qualified_name,
2688 &functions,
2689 &func_badness,
2690 no_adl);
2691
2692 if (func_oload_champ >= 0)
2693 func_match_quality = classify_oload_match (func_badness,
2694 args.size (), 0);
2695 }
2696
2697 /* Did we find a match ? */
2698 if (method_oload_champ == -1 && func_oload_champ == -1)
2699 throw_error (NOT_FOUND_ERROR,
2700 _("No symbol \"%s\" in current context."),
2701 name);
2702
2703 /* If we have found both a method match and a function
2704 match, find out which one is better, and calculate match
2705 quality. */
2706 if (method_oload_champ >= 0 && func_oload_champ >= 0)
2707 {
2708 switch (compare_badness (func_badness, method_badness))
2709 {
2710 case 0: /* Top two contenders are equally good. */
2711 /* FIXME: GDB does not support the general ambiguous case.
2712 All candidates should be collected and presented the
2713 user. */
2714 error (_("Ambiguous overload resolution"));
2715 break;
2716 case 1: /* Incomparable top contenders. */
2717 /* This is an error incompatible candidates
2718 should not have been proposed. */
2719 error (_("Internal error: incompatible "
2720 "overload candidates proposed"));
2721 break;
2722 case 2: /* Function champion. */
2723 method_oload_champ = -1;
2724 match_quality = func_match_quality;
2725 break;
2726 case 3: /* Method champion. */
2727 func_oload_champ = -1;
2728 match_quality = method_match_quality;
2729 break;
2730 default:
2731 error (_("Internal error: unexpected overload comparison result"));
2732 break;
2733 }
2734 }
2735 else
2736 {
2737 /* We have either a method match or a function match. */
2738 if (method_oload_champ >= 0)
2739 match_quality = method_match_quality;
2740 else
2741 match_quality = func_match_quality;
2742 }
2743
2744 if (match_quality == INCOMPATIBLE)
2745 {
2746 if (method == METHOD)
2747 error (_("Cannot resolve method %s%s%s to any overloaded instance"),
2748 obj_type_name,
2749 (obj_type_name && *obj_type_name) ? "::" : "",
2750 name);
2751 else
2752 error (_("Cannot resolve function %s to any overloaded instance"),
2753 func_name);
2754 }
2755 else if (match_quality == NON_STANDARD)
2756 {
2757 if (method == METHOD)
2758 warning (_("Using non-standard conversion to match "
2759 "method %s%s%s to supplied arguments"),
2760 obj_type_name,
2761 (obj_type_name && *obj_type_name) ? "::" : "",
2762 name);
2763 else
2764 warning (_("Using non-standard conversion to match "
2765 "function %s to supplied arguments"),
2766 func_name);
2767 }
2768
2769 if (staticp != NULL)
2770 *staticp = oload_method_static_p (methods.data (), method_oload_champ);
2771
2772 if (method_oload_champ >= 0)
2773 {
2774 if (src_method_oload_champ >= 0)
2775 {
2776 if (TYPE_FN_FIELD_VIRTUAL_P (methods, method_oload_champ)
2777 && noside != EVAL_AVOID_SIDE_EFFECTS)
2778 {
2779 *valp = value_virtual_fn_field (&temp, methods.data (),
2780 method_oload_champ, basetype,
2781 boffset);
2782 }
2783 else
2784 *valp = value_fn_field (&temp, methods.data (),
2785 method_oload_champ, basetype, boffset);
2786 }
2787 else
2788 *valp = value_from_xmethod
2789 (std::move (xmethods[ext_method_oload_champ]));
2790 }
2791 else
2792 *symp = functions[func_oload_champ];
2793
2794 if (objp)
2795 {
2796 struct type *temp_type = check_typedef (value_type (temp));
2797 struct type *objtype = check_typedef (obj_type);
2798
2799 if (TYPE_CODE (temp_type) != TYPE_CODE_PTR
2800 && (TYPE_CODE (objtype) == TYPE_CODE_PTR
2801 || TYPE_IS_REFERENCE (objtype)))
2802 {
2803 temp = value_addr (temp);
2804 }
2805 *objp = temp;
2806 }
2807
2808 switch (match_quality)
2809 {
2810 case INCOMPATIBLE:
2811 return 100;
2812 case NON_STANDARD:
2813 return 10;
2814 default: /* STANDARD */
2815 return 0;
2816 }
2817 }
2818
2819 /* Find the best overload match, searching for FUNC_NAME in namespaces
2820 contained in QUALIFIED_NAME until it either finds a good match or
2821 runs out of namespaces. It stores the overloaded functions in
2822 *OLOAD_SYMS, and the badness vector in *OLOAD_CHAMP_BV. If NO_ADL,
2823 argument dependent lookup is not performned. */
2824
2825 static int
2826 find_oload_champ_namespace (gdb::array_view<value *> args,
2827 const char *func_name,
2828 const char *qualified_name,
2829 std::vector<symbol *> *oload_syms,
2830 badness_vector *oload_champ_bv,
2831 const int no_adl)
2832 {
2833 int oload_champ;
2834
2835 find_oload_champ_namespace_loop (args,
2836 func_name,
2837 qualified_name, 0,
2838 oload_syms, oload_champ_bv,
2839 &oload_champ,
2840 no_adl);
2841
2842 return oload_champ;
2843 }
2844
2845 /* Helper function for find_oload_champ_namespace; NAMESPACE_LEN is
2846 how deep we've looked for namespaces, and the champ is stored in
2847 OLOAD_CHAMP. The return value is 1 if the champ is a good one, 0
2848 if it isn't. Other arguments are the same as in
2849 find_oload_champ_namespace. */
2850
2851 static int
2852 find_oload_champ_namespace_loop (gdb::array_view<value *> args,
2853 const char *func_name,
2854 const char *qualified_name,
2855 int namespace_len,
2856 std::vector<symbol *> *oload_syms,
2857 badness_vector *oload_champ_bv,
2858 int *oload_champ,
2859 const int no_adl)
2860 {
2861 int next_namespace_len = namespace_len;
2862 int searched_deeper = 0;
2863 int new_oload_champ;
2864 char *new_namespace;
2865
2866 if (next_namespace_len != 0)
2867 {
2868 gdb_assert (qualified_name[next_namespace_len] == ':');
2869 next_namespace_len += 2;
2870 }
2871 next_namespace_len +=
2872 cp_find_first_component (qualified_name + next_namespace_len);
2873
2874 /* First, see if we have a deeper namespace we can search in.
2875 If we get a good match there, use it. */
2876
2877 if (qualified_name[next_namespace_len] == ':')
2878 {
2879 searched_deeper = 1;
2880
2881 if (find_oload_champ_namespace_loop (args,
2882 func_name, qualified_name,
2883 next_namespace_len,
2884 oload_syms, oload_champ_bv,
2885 oload_champ, no_adl))
2886 {
2887 return 1;
2888 }
2889 };
2890
2891 /* If we reach here, either we're in the deepest namespace or we
2892 didn't find a good match in a deeper namespace. But, in the
2893 latter case, we still have a bad match in a deeper namespace;
2894 note that we might not find any match at all in the current
2895 namespace. (There's always a match in the deepest namespace,
2896 because this overload mechanism only gets called if there's a
2897 function symbol to start off with.) */
2898
2899 new_namespace = (char *) alloca (namespace_len + 1);
2900 strncpy (new_namespace, qualified_name, namespace_len);
2901 new_namespace[namespace_len] = '\0';
2902
2903 std::vector<symbol *> new_oload_syms
2904 = make_symbol_overload_list (func_name, new_namespace);
2905
2906 /* If we have reached the deepest level perform argument
2907 determined lookup. */
2908 if (!searched_deeper && !no_adl)
2909 {
2910 int ix;
2911 struct type **arg_types;
2912
2913 /* Prepare list of argument types for overload resolution. */
2914 arg_types = (struct type **)
2915 alloca (args.size () * (sizeof (struct type *)));
2916 for (ix = 0; ix < args.size (); ix++)
2917 arg_types[ix] = value_type (args[ix]);
2918 add_symbol_overload_list_adl ({arg_types, args.size ()}, func_name,
2919 &new_oload_syms);
2920 }
2921
2922 badness_vector new_oload_champ_bv;
2923 new_oload_champ = find_oload_champ (args,
2924 new_oload_syms.size (),
2925 NULL, NULL, new_oload_syms.data (),
2926 &new_oload_champ_bv);
2927
2928 /* Case 1: We found a good match. Free earlier matches (if any),
2929 and return it. Case 2: We didn't find a good match, but we're
2930 not the deepest function. Then go with the bad match that the
2931 deeper function found. Case 3: We found a bad match, and we're
2932 the deepest function. Then return what we found, even though
2933 it's a bad match. */
2934
2935 if (new_oload_champ != -1
2936 && classify_oload_match (new_oload_champ_bv, args.size (), 0) == STANDARD)
2937 {
2938 *oload_syms = std::move (new_oload_syms);
2939 *oload_champ = new_oload_champ;
2940 *oload_champ_bv = std::move (new_oload_champ_bv);
2941 return 1;
2942 }
2943 else if (searched_deeper)
2944 {
2945 return 0;
2946 }
2947 else
2948 {
2949 *oload_syms = std::move (new_oload_syms);
2950 *oload_champ = new_oload_champ;
2951 *oload_champ_bv = std::move (new_oload_champ_bv);
2952 return 0;
2953 }
2954 }
2955
2956 /* Look for a function to take ARGS. Find the best match from among
2957 the overloaded methods or functions given by METHODS or FUNCTIONS
2958 or XMETHODS, respectively. One, and only one of METHODS, FUNCTIONS
2959 and XMETHODS can be non-NULL.
2960
2961 NUM_FNS is the length of the array pointed at by METHODS, FUNCTIONS
2962 or XMETHODS, whichever is non-NULL.
2963
2964 Return the index of the best match; store an indication of the
2965 quality of the match in OLOAD_CHAMP_BV. */
2966
2967 static int
2968 find_oload_champ (gdb::array_view<value *> args,
2969 size_t num_fns,
2970 fn_field *methods,
2971 xmethod_worker_up *xmethods,
2972 symbol **functions,
2973 badness_vector *oload_champ_bv)
2974 {
2975 /* A measure of how good an overloaded instance is. */
2976 badness_vector bv;
2977 /* Index of best overloaded function. */
2978 int oload_champ = -1;
2979 /* Current ambiguity state for overload resolution. */
2980 int oload_ambiguous = 0;
2981 /* 0 => no ambiguity, 1 => two good funcs, 2 => incomparable funcs. */
2982
2983 /* A champion can be found among methods alone, or among functions
2984 alone, or in xmethods alone, but not in more than one of these
2985 groups. */
2986 gdb_assert ((methods != NULL) + (functions != NULL) + (xmethods != NULL)
2987 == 1);
2988
2989 /* Consider each candidate in turn. */
2990 for (size_t ix = 0; ix < num_fns; ix++)
2991 {
2992 int jj;
2993 int static_offset = 0;
2994 std::vector<type *> parm_types;
2995
2996 if (xmethods != NULL)
2997 parm_types = xmethods[ix]->get_arg_types ();
2998 else
2999 {
3000 size_t nparms;
3001
3002 if (methods != NULL)
3003 {
3004 nparms = TYPE_NFIELDS (TYPE_FN_FIELD_TYPE (methods, ix));
3005 static_offset = oload_method_static_p (methods, ix);
3006 }
3007 else
3008 nparms = TYPE_NFIELDS (SYMBOL_TYPE (functions[ix]));
3009
3010 parm_types.reserve (nparms);
3011 for (jj = 0; jj < nparms; jj++)
3012 {
3013 type *t = (methods != NULL
3014 ? (TYPE_FN_FIELD_ARGS (methods, ix)[jj].type)
3015 : TYPE_FIELD_TYPE (SYMBOL_TYPE (functions[ix]),
3016 jj));
3017 parm_types.push_back (t);
3018 }
3019 }
3020
3021 /* Compare parameter types to supplied argument types. Skip
3022 THIS for static methods. */
3023 bv = rank_function (parm_types,
3024 args.slice (static_offset));
3025
3026 if (oload_champ_bv->empty ())
3027 {
3028 *oload_champ_bv = std::move (bv);
3029 oload_champ = 0;
3030 }
3031 else /* See whether current candidate is better or worse than
3032 previous best. */
3033 switch (compare_badness (bv, *oload_champ_bv))
3034 {
3035 case 0: /* Top two contenders are equally good. */
3036 oload_ambiguous = 1;
3037 break;
3038 case 1: /* Incomparable top contenders. */
3039 oload_ambiguous = 2;
3040 break;
3041 case 2: /* New champion, record details. */
3042 *oload_champ_bv = std::move (bv);
3043 oload_ambiguous = 0;
3044 oload_champ = ix;
3045 break;
3046 case 3:
3047 default:
3048 break;
3049 }
3050 if (overload_debug)
3051 {
3052 if (methods != NULL)
3053 fprintf_filtered (gdb_stderr,
3054 "Overloaded method instance %s, # of parms %d\n",
3055 methods[ix].physname, (int) parm_types.size ());
3056 else if (xmethods != NULL)
3057 fprintf_filtered (gdb_stderr,
3058 "Xmethod worker, # of parms %d\n",
3059 (int) parm_types.size ());
3060 else
3061 fprintf_filtered (gdb_stderr,
3062 "Overloaded function instance "
3063 "%s # of parms %d\n",
3064 SYMBOL_DEMANGLED_NAME (functions[ix]),
3065 (int) parm_types.size ());
3066 for (jj = 0; jj < args.size () - static_offset; jj++)
3067 fprintf_filtered (gdb_stderr,
3068 "...Badness @ %d : %d\n",
3069 jj, bv[jj].rank);
3070 fprintf_filtered (gdb_stderr, "Overload resolution "
3071 "champion is %d, ambiguous? %d\n",
3072 oload_champ, oload_ambiguous);
3073 }
3074 }
3075
3076 return oload_champ;
3077 }
3078
3079 /* Return 1 if we're looking at a static method, 0 if we're looking at
3080 a non-static method or a function that isn't a method. */
3081
3082 static int
3083 oload_method_static_p (struct fn_field *fns_ptr, int index)
3084 {
3085 if (fns_ptr && index >= 0 && TYPE_FN_FIELD_STATIC_P (fns_ptr, index))
3086 return 1;
3087 else
3088 return 0;
3089 }
3090
3091 /* Check how good an overload match OLOAD_CHAMP_BV represents. */
3092
3093 static enum oload_classification
3094 classify_oload_match (const badness_vector &oload_champ_bv,
3095 int nargs,
3096 int static_offset)
3097 {
3098 int ix;
3099 enum oload_classification worst = STANDARD;
3100
3101 for (ix = 1; ix <= nargs - static_offset; ix++)
3102 {
3103 /* If this conversion is as bad as INCOMPATIBLE_TYPE_BADNESS
3104 or worse return INCOMPATIBLE. */
3105 if (compare_ranks (oload_champ_bv[ix],
3106 INCOMPATIBLE_TYPE_BADNESS) <= 0)
3107 return INCOMPATIBLE; /* Truly mismatched types. */
3108 /* Otherwise If this conversion is as bad as
3109 NS_POINTER_CONVERSION_BADNESS or worse return NON_STANDARD. */
3110 else if (compare_ranks (oload_champ_bv[ix],
3111 NS_POINTER_CONVERSION_BADNESS) <= 0)
3112 worst = NON_STANDARD; /* Non-standard type conversions
3113 needed. */
3114 }
3115
3116 /* If no INCOMPATIBLE classification was found, return the worst one
3117 that was found (if any). */
3118 return worst;
3119 }
3120
3121 /* C++: return 1 is NAME is a legitimate name for the destructor of
3122 type TYPE. If TYPE does not have a destructor, or if NAME is
3123 inappropriate for TYPE, an error is signaled. Parameter TYPE should not yet
3124 have CHECK_TYPEDEF applied, this function will apply it itself. */
3125
3126 int
3127 destructor_name_p (const char *name, struct type *type)
3128 {
3129 if (name[0] == '~')
3130 {
3131 const char *dname = type_name_or_error (type);
3132 const char *cp = strchr (dname, '<');
3133 unsigned int len;
3134
3135 /* Do not compare the template part for template classes. */
3136 if (cp == NULL)
3137 len = strlen (dname);
3138 else
3139 len = cp - dname;
3140 if (strlen (name + 1) != len || strncmp (dname, name + 1, len) != 0)
3141 error (_("name of destructor must equal name of class"));
3142 else
3143 return 1;
3144 }
3145 return 0;
3146 }
3147
3148 /* Find an enum constant named NAME in TYPE. TYPE must be an "enum
3149 class". If the name is found, return a value representing it;
3150 otherwise throw an exception. */
3151
3152 static struct value *
3153 enum_constant_from_type (struct type *type, const char *name)
3154 {
3155 int i;
3156 int name_len = strlen (name);
3157
3158 gdb_assert (TYPE_CODE (type) == TYPE_CODE_ENUM
3159 && TYPE_DECLARED_CLASS (type));
3160
3161 for (i = TYPE_N_BASECLASSES (type); i < TYPE_NFIELDS (type); ++i)
3162 {
3163 const char *fname = TYPE_FIELD_NAME (type, i);
3164 int len;
3165
3166 if (TYPE_FIELD_LOC_KIND (type, i) != FIELD_LOC_KIND_ENUMVAL
3167 || fname == NULL)
3168 continue;
3169
3170 /* Look for the trailing "::NAME", since enum class constant
3171 names are qualified here. */
3172 len = strlen (fname);
3173 if (len + 2 >= name_len
3174 && fname[len - name_len - 2] == ':'
3175 && fname[len - name_len - 1] == ':'
3176 && strcmp (&fname[len - name_len], name) == 0)
3177 return value_from_longest (type, TYPE_FIELD_ENUMVAL (type, i));
3178 }
3179
3180 error (_("no constant named \"%s\" in enum \"%s\""),
3181 name, TYPE_NAME (type));
3182 }
3183
3184 /* C++: Given an aggregate type CURTYPE, and a member name NAME,
3185 return the appropriate member (or the address of the member, if
3186 WANT_ADDRESS). This function is used to resolve user expressions
3187 of the form "DOMAIN::NAME". For more details on what happens, see
3188 the comment before value_struct_elt_for_reference. */
3189
3190 struct value *
3191 value_aggregate_elt (struct type *curtype, const char *name,
3192 struct type *expect_type, int want_address,
3193 enum noside noside)
3194 {
3195 switch (TYPE_CODE (curtype))
3196 {
3197 case TYPE_CODE_STRUCT:
3198 case TYPE_CODE_UNION:
3199 return value_struct_elt_for_reference (curtype, 0, curtype,
3200 name, expect_type,
3201 want_address, noside);
3202 case TYPE_CODE_NAMESPACE:
3203 return value_namespace_elt (curtype, name,
3204 want_address, noside);
3205
3206 case TYPE_CODE_ENUM:
3207 return enum_constant_from_type (curtype, name);
3208
3209 default:
3210 internal_error (__FILE__, __LINE__,
3211 _("non-aggregate type in value_aggregate_elt"));
3212 }
3213 }
3214
3215 /* Compares the two method/function types T1 and T2 for "equality"
3216 with respect to the methods' parameters. If the types of the
3217 two parameter lists are the same, returns 1; 0 otherwise. This
3218 comparison may ignore any artificial parameters in T1 if
3219 SKIP_ARTIFICIAL is non-zero. This function will ALWAYS skip
3220 the first artificial parameter in T1, assumed to be a 'this' pointer.
3221
3222 The type T2 is expected to have come from make_params (in eval.c). */
3223
3224 static int
3225 compare_parameters (struct type *t1, struct type *t2, int skip_artificial)
3226 {
3227 int start = 0;
3228
3229 if (TYPE_NFIELDS (t1) > 0 && TYPE_FIELD_ARTIFICIAL (t1, 0))
3230 ++start;
3231
3232 /* If skipping artificial fields, find the first real field
3233 in T1. */
3234 if (skip_artificial)
3235 {
3236 while (start < TYPE_NFIELDS (t1)
3237 && TYPE_FIELD_ARTIFICIAL (t1, start))
3238 ++start;
3239 }
3240
3241 /* Now compare parameters. */
3242
3243 /* Special case: a method taking void. T1 will contain no
3244 non-artificial fields, and T2 will contain TYPE_CODE_VOID. */
3245 if ((TYPE_NFIELDS (t1) - start) == 0 && TYPE_NFIELDS (t2) == 1
3246 && TYPE_CODE (TYPE_FIELD_TYPE (t2, 0)) == TYPE_CODE_VOID)
3247 return 1;
3248
3249 if ((TYPE_NFIELDS (t1) - start) == TYPE_NFIELDS (t2))
3250 {
3251 int i;
3252
3253 for (i = 0; i < TYPE_NFIELDS (t2); ++i)
3254 {
3255 if (compare_ranks (rank_one_type (TYPE_FIELD_TYPE (t1, start + i),
3256 TYPE_FIELD_TYPE (t2, i), NULL),
3257 EXACT_MATCH_BADNESS) != 0)
3258 return 0;
3259 }
3260
3261 return 1;
3262 }
3263
3264 return 0;
3265 }
3266
3267 /* C++: Given an aggregate type VT, and a class type CLS, search
3268 recursively for CLS using value V; If found, store the offset
3269 which is either fetched from the virtual base pointer if CLS
3270 is virtual or accumulated offset of its parent classes if
3271 CLS is non-virtual in *BOFFS, set ISVIRT to indicate if CLS
3272 is virtual, and return true. If not found, return false. */
3273
3274 static bool
3275 get_baseclass_offset (struct type *vt, struct type *cls,
3276 struct value *v, int *boffs, bool *isvirt)
3277 {
3278 for (int i = 0; i < TYPE_N_BASECLASSES (vt); i++)
3279 {
3280 struct type *t = TYPE_FIELD_TYPE (vt, i);
3281 if (types_equal (t, cls))
3282 {
3283 if (BASETYPE_VIA_VIRTUAL (vt, i))
3284 {
3285 const gdb_byte *adr = value_contents_for_printing (v);
3286 *boffs = baseclass_offset (vt, i, adr, value_offset (v),
3287 value_as_long (v), v);
3288 *isvirt = true;
3289 }
3290 else
3291 *isvirt = false;
3292 return true;
3293 }
3294
3295 if (get_baseclass_offset (check_typedef (t), cls, v, boffs, isvirt))
3296 {
3297 if (*isvirt == false) /* Add non-virtual base offset. */
3298 {
3299 const gdb_byte *adr = value_contents_for_printing (v);
3300 *boffs += baseclass_offset (vt, i, adr, value_offset (v),
3301 value_as_long (v), v);
3302 }
3303 return true;
3304 }
3305 }
3306
3307 return false;
3308 }
3309
3310 /* C++: Given an aggregate type CURTYPE, and a member name NAME,
3311 return the address of this member as a "pointer to member" type.
3312 If INTYPE is non-null, then it will be the type of the member we
3313 are looking for. This will help us resolve "pointers to member
3314 functions". This function is used to resolve user expressions of
3315 the form "DOMAIN::NAME". */
3316
3317 static struct value *
3318 value_struct_elt_for_reference (struct type *domain, int offset,
3319 struct type *curtype, const char *name,
3320 struct type *intype,
3321 int want_address,
3322 enum noside noside)
3323 {
3324 struct type *t = check_typedef (curtype);
3325 int i;
3326 struct value *result;
3327
3328 if (TYPE_CODE (t) != TYPE_CODE_STRUCT
3329 && TYPE_CODE (t) != TYPE_CODE_UNION)
3330 error (_("Internal error: non-aggregate type "
3331 "to value_struct_elt_for_reference"));
3332
3333 for (i = TYPE_NFIELDS (t) - 1; i >= TYPE_N_BASECLASSES (t); i--)
3334 {
3335 const char *t_field_name = TYPE_FIELD_NAME (t, i);
3336
3337 if (t_field_name && strcmp (t_field_name, name) == 0)
3338 {
3339 if (field_is_static (&TYPE_FIELD (t, i)))
3340 {
3341 struct value *v = value_static_field (t, i);
3342 if (want_address)
3343 v = value_addr (v);
3344 return v;
3345 }
3346 if (TYPE_FIELD_PACKED (t, i))
3347 error (_("pointers to bitfield members not allowed"));
3348
3349 if (want_address)
3350 return value_from_longest
3351 (lookup_memberptr_type (TYPE_FIELD_TYPE (t, i), domain),
3352 offset + (LONGEST) (TYPE_FIELD_BITPOS (t, i) >> 3));
3353 else if (noside != EVAL_NORMAL)
3354 return allocate_value (TYPE_FIELD_TYPE (t, i));
3355 else
3356 {
3357 /* Try to evaluate NAME as a qualified name with implicit
3358 this pointer. In this case, attempt to return the
3359 equivalent to `this->*(&TYPE::NAME)'. */
3360 struct value *v = value_of_this_silent (current_language);
3361 if (v != NULL)
3362 {
3363 struct value *ptr, *this_v = v;
3364 long mem_offset;
3365 struct type *type, *tmp;
3366
3367 ptr = value_aggregate_elt (domain, name, NULL, 1, noside);
3368 type = check_typedef (value_type (ptr));
3369 gdb_assert (type != NULL
3370 && TYPE_CODE (type) == TYPE_CODE_MEMBERPTR);
3371 tmp = lookup_pointer_type (TYPE_SELF_TYPE (type));
3372 v = value_cast_pointers (tmp, v, 1);
3373 mem_offset = value_as_long (ptr);
3374 if (domain != curtype)
3375 {
3376 /* Find class offset of type CURTYPE from either its
3377 parent type DOMAIN or the type of implied this. */
3378 int boff = 0;
3379 bool isvirt = false;
3380 if (get_baseclass_offset (domain, curtype, v, &boff,
3381 &isvirt))
3382 mem_offset += boff;
3383 else
3384 {
3385 struct type *p = check_typedef (value_type (this_v));
3386 p = check_typedef (TYPE_TARGET_TYPE (p));
3387 if (get_baseclass_offset (p, curtype, this_v,
3388 &boff, &isvirt))
3389 mem_offset += boff;
3390 }
3391 }
3392 tmp = lookup_pointer_type (TYPE_TARGET_TYPE (type));
3393 result = value_from_pointer (tmp,
3394 value_as_long (v) + mem_offset);
3395 return value_ind (result);
3396 }
3397
3398 error (_("Cannot reference non-static field \"%s\""), name);
3399 }
3400 }
3401 }
3402
3403 /* C++: If it was not found as a data field, then try to return it
3404 as a pointer to a method. */
3405
3406 /* Perform all necessary dereferencing. */
3407 while (intype && TYPE_CODE (intype) == TYPE_CODE_PTR)
3408 intype = TYPE_TARGET_TYPE (intype);
3409
3410 for (i = TYPE_NFN_FIELDS (t) - 1; i >= 0; --i)
3411 {
3412 const char *t_field_name = TYPE_FN_FIELDLIST_NAME (t, i);
3413
3414 if (t_field_name && strcmp (t_field_name, name) == 0)
3415 {
3416 int j;
3417 int len = TYPE_FN_FIELDLIST_LENGTH (t, i);
3418 struct fn_field *f = TYPE_FN_FIELDLIST1 (t, i);
3419
3420 check_stub_method_group (t, i);
3421
3422 if (intype)
3423 {
3424 for (j = 0; j < len; ++j)
3425 {
3426 if (TYPE_CONST (intype) != TYPE_FN_FIELD_CONST (f, j))
3427 continue;
3428 if (TYPE_VOLATILE (intype) != TYPE_FN_FIELD_VOLATILE (f, j))
3429 continue;
3430
3431 if (compare_parameters (TYPE_FN_FIELD_TYPE (f, j), intype, 0)
3432 || compare_parameters (TYPE_FN_FIELD_TYPE (f, j),
3433 intype, 1))
3434 break;
3435 }
3436
3437 if (j == len)
3438 error (_("no member function matches "
3439 "that type instantiation"));
3440 }
3441 else
3442 {
3443 int ii;
3444
3445 j = -1;
3446 for (ii = 0; ii < len; ++ii)
3447 {
3448 /* Skip artificial methods. This is necessary if,
3449 for example, the user wants to "print
3450 subclass::subclass" with only one user-defined
3451 constructor. There is no ambiguity in this case.
3452 We are careful here to allow artificial methods
3453 if they are the unique result. */
3454 if (TYPE_FN_FIELD_ARTIFICIAL (f, ii))
3455 {
3456 if (j == -1)
3457 j = ii;
3458 continue;
3459 }
3460
3461 /* Desired method is ambiguous if more than one
3462 method is defined. */
3463 if (j != -1 && !TYPE_FN_FIELD_ARTIFICIAL (f, j))
3464 error (_("non-unique member `%s' requires "
3465 "type instantiation"), name);
3466
3467 j = ii;
3468 }
3469
3470 if (j == -1)
3471 error (_("no matching member function"));
3472 }
3473
3474 if (TYPE_FN_FIELD_STATIC_P (f, j))
3475 {
3476 struct symbol *s =
3477 lookup_symbol (TYPE_FN_FIELD_PHYSNAME (f, j),
3478 0, VAR_DOMAIN, 0).symbol;
3479
3480 if (s == NULL)
3481 return NULL;
3482
3483 if (want_address)
3484 return value_addr (read_var_value (s, 0, 0));
3485 else
3486 return read_var_value (s, 0, 0);
3487 }
3488
3489 if (TYPE_FN_FIELD_VIRTUAL_P (f, j))
3490 {
3491 if (want_address)
3492 {
3493 result = allocate_value
3494 (lookup_methodptr_type (TYPE_FN_FIELD_TYPE (f, j)));
3495 cplus_make_method_ptr (value_type (result),
3496 value_contents_writeable (result),
3497 TYPE_FN_FIELD_VOFFSET (f, j), 1);
3498 }
3499 else if (noside == EVAL_AVOID_SIDE_EFFECTS)
3500 return allocate_value (TYPE_FN_FIELD_TYPE (f, j));
3501 else
3502 error (_("Cannot reference virtual member function \"%s\""),
3503 name);
3504 }
3505 else
3506 {
3507 struct symbol *s =
3508 lookup_symbol (TYPE_FN_FIELD_PHYSNAME (f, j),
3509 0, VAR_DOMAIN, 0).symbol;
3510
3511 if (s == NULL)
3512 return NULL;
3513
3514 struct value *v = read_var_value (s, 0, 0);
3515 if (!want_address)
3516 result = v;
3517 else
3518 {
3519 result = allocate_value (lookup_methodptr_type (TYPE_FN_FIELD_TYPE (f, j)));
3520 cplus_make_method_ptr (value_type (result),
3521 value_contents_writeable (result),
3522 value_address (v), 0);
3523 }
3524 }
3525 return result;
3526 }
3527 }
3528 for (i = TYPE_N_BASECLASSES (t) - 1; i >= 0; i--)
3529 {
3530 struct value *v;
3531 int base_offset;
3532
3533 if (BASETYPE_VIA_VIRTUAL (t, i))
3534 base_offset = 0;
3535 else
3536 base_offset = TYPE_BASECLASS_BITPOS (t, i) / 8;
3537 v = value_struct_elt_for_reference (domain,
3538 offset + base_offset,
3539 TYPE_BASECLASS (t, i),
3540 name, intype,
3541 want_address, noside);
3542 if (v)
3543 return v;
3544 }
3545
3546 /* As a last chance, pretend that CURTYPE is a namespace, and look
3547 it up that way; this (frequently) works for types nested inside
3548 classes. */
3549
3550 return value_maybe_namespace_elt (curtype, name,
3551 want_address, noside);
3552 }
3553
3554 /* C++: Return the member NAME of the namespace given by the type
3555 CURTYPE. */
3556
3557 static struct value *
3558 value_namespace_elt (const struct type *curtype,
3559 const char *name, int want_address,
3560 enum noside noside)
3561 {
3562 struct value *retval = value_maybe_namespace_elt (curtype, name,
3563 want_address,
3564 noside);
3565
3566 if (retval == NULL)
3567 error (_("No symbol \"%s\" in namespace \"%s\"."),
3568 name, TYPE_NAME (curtype));
3569
3570 return retval;
3571 }
3572
3573 /* A helper function used by value_namespace_elt and
3574 value_struct_elt_for_reference. It looks up NAME inside the
3575 context CURTYPE; this works if CURTYPE is a namespace or if CURTYPE
3576 is a class and NAME refers to a type in CURTYPE itself (as opposed
3577 to, say, some base class of CURTYPE). */
3578
3579 static struct value *
3580 value_maybe_namespace_elt (const struct type *curtype,
3581 const char *name, int want_address,
3582 enum noside noside)
3583 {
3584 const char *namespace_name = TYPE_NAME (curtype);
3585 struct block_symbol sym;
3586 struct value *result;
3587
3588 sym = cp_lookup_symbol_namespace (namespace_name, name,
3589 get_selected_block (0), VAR_DOMAIN);
3590
3591 if (sym.symbol == NULL)
3592 return NULL;
3593 else if ((noside == EVAL_AVOID_SIDE_EFFECTS)
3594 && (SYMBOL_CLASS (sym.symbol) == LOC_TYPEDEF))
3595 result = allocate_value (SYMBOL_TYPE (sym.symbol));
3596 else
3597 result = value_of_variable (sym.symbol, sym.block);
3598
3599 if (want_address)
3600 result = value_addr (result);
3601
3602 return result;
3603 }
3604
3605 /* Given a pointer or a reference value V, find its real (RTTI) type.
3606
3607 Other parameters FULL, TOP, USING_ENC as with value_rtti_type()
3608 and refer to the values computed for the object pointed to. */
3609
3610 struct type *
3611 value_rtti_indirect_type (struct value *v, int *full,
3612 LONGEST *top, int *using_enc)
3613 {
3614 struct value *target = NULL;
3615 struct type *type, *real_type, *target_type;
3616
3617 type = value_type (v);
3618 type = check_typedef (type);
3619 if (TYPE_IS_REFERENCE (type))
3620 target = coerce_ref (v);
3621 else if (TYPE_CODE (type) == TYPE_CODE_PTR)
3622 {
3623
3624 TRY
3625 {
3626 target = value_ind (v);
3627 }
3628 CATCH (except, RETURN_MASK_ERROR)
3629 {
3630 if (except.error == MEMORY_ERROR)
3631 {
3632 /* value_ind threw a memory error. The pointer is NULL or
3633 contains an uninitialized value: we can't determine any
3634 type. */
3635 return NULL;
3636 }
3637 throw_exception (except);
3638 }
3639 END_CATCH
3640 }
3641 else
3642 return NULL;
3643
3644 real_type = value_rtti_type (target, full, top, using_enc);
3645
3646 if (real_type)
3647 {
3648 /* Copy qualifiers to the referenced object. */
3649 target_type = value_type (target);
3650 real_type = make_cv_type (TYPE_CONST (target_type),
3651 TYPE_VOLATILE (target_type), real_type, NULL);
3652 if (TYPE_IS_REFERENCE (type))
3653 real_type = lookup_reference_type (real_type, TYPE_CODE (type));
3654 else if (TYPE_CODE (type) == TYPE_CODE_PTR)
3655 real_type = lookup_pointer_type (real_type);
3656 else
3657 internal_error (__FILE__, __LINE__, _("Unexpected value type."));
3658
3659 /* Copy qualifiers to the pointer/reference. */
3660 real_type = make_cv_type (TYPE_CONST (type), TYPE_VOLATILE (type),
3661 real_type, NULL);
3662 }
3663
3664 return real_type;
3665 }
3666
3667 /* Given a value pointed to by ARGP, check its real run-time type, and
3668 if that is different from the enclosing type, create a new value
3669 using the real run-time type as the enclosing type (and of the same
3670 type as ARGP) and return it, with the embedded offset adjusted to
3671 be the correct offset to the enclosed object. RTYPE is the type,
3672 and XFULL, XTOP, and XUSING_ENC are the other parameters, computed
3673 by value_rtti_type(). If these are available, they can be supplied
3674 and a second call to value_rtti_type() is avoided. (Pass RTYPE ==
3675 NULL if they're not available. */
3676
3677 struct value *
3678 value_full_object (struct value *argp,
3679 struct type *rtype,
3680 int xfull, int xtop,
3681 int xusing_enc)
3682 {
3683 struct type *real_type;
3684 int full = 0;
3685 LONGEST top = -1;
3686 int using_enc = 0;
3687 struct value *new_val;
3688
3689 if (rtype)
3690 {
3691 real_type = rtype;
3692 full = xfull;
3693 top = xtop;
3694 using_enc = xusing_enc;
3695 }
3696 else
3697 real_type = value_rtti_type (argp, &full, &top, &using_enc);
3698
3699 /* If no RTTI data, or if object is already complete, do nothing. */
3700 if (!real_type || real_type == value_enclosing_type (argp))
3701 return argp;
3702
3703 /* In a destructor we might see a real type that is a superclass of
3704 the object's type. In this case it is better to leave the object
3705 as-is. */
3706 if (full
3707 && TYPE_LENGTH (real_type) < TYPE_LENGTH (value_enclosing_type (argp)))
3708 return argp;
3709
3710 /* If we have the full object, but for some reason the enclosing
3711 type is wrong, set it. */
3712 /* pai: FIXME -- sounds iffy */
3713 if (full)
3714 {
3715 argp = value_copy (argp);
3716 set_value_enclosing_type (argp, real_type);
3717 return argp;
3718 }
3719
3720 /* Check if object is in memory. */
3721 if (VALUE_LVAL (argp) != lval_memory)
3722 {
3723 warning (_("Couldn't retrieve complete object of RTTI "
3724 "type %s; object may be in register(s)."),
3725 TYPE_NAME (real_type));
3726
3727 return argp;
3728 }
3729
3730 /* All other cases -- retrieve the complete object. */
3731 /* Go back by the computed top_offset from the beginning of the
3732 object, adjusting for the embedded offset of argp if that's what
3733 value_rtti_type used for its computation. */
3734 new_val = value_at_lazy (real_type, value_address (argp) - top +
3735 (using_enc ? 0 : value_embedded_offset (argp)));
3736 deprecated_set_value_type (new_val, value_type (argp));
3737 set_value_embedded_offset (new_val, (using_enc
3738 ? top + value_embedded_offset (argp)
3739 : top));
3740 return new_val;
3741 }
3742
3743
3744 /* Return the value of the local variable, if one exists. Throw error
3745 otherwise, such as if the request is made in an inappropriate context. */
3746
3747 struct value *
3748 value_of_this (const struct language_defn *lang)
3749 {
3750 struct block_symbol sym;
3751 const struct block *b;
3752 struct frame_info *frame;
3753
3754 if (!lang->la_name_of_this)
3755 error (_("no `this' in current language"));
3756
3757 frame = get_selected_frame (_("no frame selected"));
3758
3759 b = get_frame_block (frame, NULL);
3760
3761 sym = lookup_language_this (lang, b);
3762 if (sym.symbol == NULL)
3763 error (_("current stack frame does not contain a variable named `%s'"),
3764 lang->la_name_of_this);
3765
3766 return read_var_value (sym.symbol, sym.block, frame);
3767 }
3768
3769 /* Return the value of the local variable, if one exists. Return NULL
3770 otherwise. Never throw error. */
3771
3772 struct value *
3773 value_of_this_silent (const struct language_defn *lang)
3774 {
3775 struct value *ret = NULL;
3776
3777 TRY
3778 {
3779 ret = value_of_this (lang);
3780 }
3781 CATCH (except, RETURN_MASK_ERROR)
3782 {
3783 }
3784 END_CATCH
3785
3786 return ret;
3787 }
3788
3789 /* Create a slice (sub-string, sub-array) of ARRAY, that is LENGTH
3790 elements long, starting at LOWBOUND. The result has the same lower
3791 bound as the original ARRAY. */
3792
3793 struct value *
3794 value_slice (struct value *array, int lowbound, int length)
3795 {
3796 struct type *slice_range_type, *slice_type, *range_type;
3797 LONGEST lowerbound, upperbound;
3798 struct value *slice;
3799 struct type *array_type;
3800
3801 array_type = check_typedef (value_type (array));
3802 if (TYPE_CODE (array_type) != TYPE_CODE_ARRAY
3803 && TYPE_CODE (array_type) != TYPE_CODE_STRING)
3804 error (_("cannot take slice of non-array"));
3805
3806 range_type = TYPE_INDEX_TYPE (array_type);
3807 if (get_discrete_bounds (range_type, &lowerbound, &upperbound) < 0)
3808 error (_("slice from bad array or bitstring"));
3809
3810 if (lowbound < lowerbound || length < 0
3811 || lowbound + length - 1 > upperbound)
3812 error (_("slice out of range"));
3813
3814 /* FIXME-type-allocation: need a way to free this type when we are
3815 done with it. */
3816 slice_range_type = create_static_range_type ((struct type *) NULL,
3817 TYPE_TARGET_TYPE (range_type),
3818 lowbound,
3819 lowbound + length - 1);
3820
3821 {
3822 struct type *element_type = TYPE_TARGET_TYPE (array_type);
3823 LONGEST offset
3824 = (lowbound - lowerbound) * TYPE_LENGTH (check_typedef (element_type));
3825
3826 slice_type = create_array_type ((struct type *) NULL,
3827 element_type,
3828 slice_range_type);
3829 TYPE_CODE (slice_type) = TYPE_CODE (array_type);
3830
3831 if (VALUE_LVAL (array) == lval_memory && value_lazy (array))
3832 slice = allocate_value_lazy (slice_type);
3833 else
3834 {
3835 slice = allocate_value (slice_type);
3836 value_contents_copy (slice, 0, array, offset,
3837 type_length_units (slice_type));
3838 }
3839
3840 set_value_component_location (slice, array);
3841 set_value_offset (slice, value_offset (array) + offset);
3842 }
3843
3844 return slice;
3845 }
3846
3847 /* Create a value for a FORTRAN complex number. Currently most of the
3848 time values are coerced to COMPLEX*16 (i.e. a complex number
3849 composed of 2 doubles. This really should be a smarter routine
3850 that figures out precision inteligently as opposed to assuming
3851 doubles. FIXME: fmb */
3852
3853 struct value *
3854 value_literal_complex (struct value *arg1,
3855 struct value *arg2,
3856 struct type *type)
3857 {
3858 struct value *val;
3859 struct type *real_type = TYPE_TARGET_TYPE (type);
3860
3861 val = allocate_value (type);
3862 arg1 = value_cast (real_type, arg1);
3863 arg2 = value_cast (real_type, arg2);
3864
3865 memcpy (value_contents_raw (val),
3866 value_contents (arg1), TYPE_LENGTH (real_type));
3867 memcpy (value_contents_raw (val) + TYPE_LENGTH (real_type),
3868 value_contents (arg2), TYPE_LENGTH (real_type));
3869 return val;
3870 }
3871
3872 /* Cast a value into the appropriate complex data type. */
3873
3874 static struct value *
3875 cast_into_complex (struct type *type, struct value *val)
3876 {
3877 struct type *real_type = TYPE_TARGET_TYPE (type);
3878
3879 if (TYPE_CODE (value_type (val)) == TYPE_CODE_COMPLEX)
3880 {
3881 struct type *val_real_type = TYPE_TARGET_TYPE (value_type (val));
3882 struct value *re_val = allocate_value (val_real_type);
3883 struct value *im_val = allocate_value (val_real_type);
3884
3885 memcpy (value_contents_raw (re_val),
3886 value_contents (val), TYPE_LENGTH (val_real_type));
3887 memcpy (value_contents_raw (im_val),
3888 value_contents (val) + TYPE_LENGTH (val_real_type),
3889 TYPE_LENGTH (val_real_type));
3890
3891 return value_literal_complex (re_val, im_val, type);
3892 }
3893 else if (TYPE_CODE (value_type (val)) == TYPE_CODE_FLT
3894 || TYPE_CODE (value_type (val)) == TYPE_CODE_INT)
3895 return value_literal_complex (val,
3896 value_zero (real_type, not_lval),
3897 type);
3898 else
3899 error (_("cannot cast non-number to complex"));
3900 }
3901
3902 void
3903 _initialize_valops (void)
3904 {
3905 add_setshow_boolean_cmd ("overload-resolution", class_support,
3906 &overload_resolution, _("\
3907 Set overload resolution in evaluating C++ functions."), _("\
3908 Show overload resolution in evaluating C++ functions."),
3909 NULL, NULL,
3910 show_overload_resolution,
3911 &setlist, &showlist);
3912 overload_resolution = 1;
3913 }
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