* ax-gdb.c (gen_exp_binop_rest) [BINOP_SUBSCRIPT]: Error out if
[binutils-gdb.git] / gdb / valops.c
blobb94c411f062619311eae84be313fd4ee8429d84d
1 /* Perform non-arithmetic operations on values, for GDB.
3 Copyright (C) 1986, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995,
4 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007,
5 2008, 2009, 2010 Free Software Foundation, Inc.
7 This file is part of GDB.
9 This program is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 3 of the License, or
12 (at your option) any later version.
14 This program is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
19 You should have received a copy of the GNU General Public License
20 along with this program. If not, see <http://www.gnu.org/licenses/>. */
22 #include "defs.h"
23 #include "symtab.h"
24 #include "gdbtypes.h"
25 #include "value.h"
26 #include "frame.h"
27 #include "inferior.h"
28 #include "gdbcore.h"
29 #include "target.h"
30 #include "demangle.h"
31 #include "language.h"
32 #include "gdbcmd.h"
33 #include "regcache.h"
34 #include "cp-abi.h"
35 #include "block.h"
36 #include "infcall.h"
37 #include "dictionary.h"
38 #include "cp-support.h"
39 #include "dfp.h"
40 #include "user-regs.h"
42 #include <errno.h>
43 #include "gdb_string.h"
44 #include "gdb_assert.h"
45 #include "cp-support.h"
46 #include "observer.h"
47 #include "objfiles.h"
48 #include "symtab.h"
50 extern int overload_debug;
51 /* Local functions. */
53 static int typecmp (int staticp, int varargs, int nargs,
54 struct field t1[], struct value *t2[]);
56 static struct value *search_struct_field (const char *, struct value *,
57 int, struct type *, int);
59 static struct value *search_struct_method (const char *, struct value **,
60 struct value **,
61 int, int *, struct type *);
63 static int find_oload_champ_namespace (struct type **, int,
64 const char *, const char *,
65 struct symbol ***,
66 struct badness_vector **);
68 static
69 int find_oload_champ_namespace_loop (struct type **, int,
70 const char *, const char *,
71 int, struct symbol ***,
72 struct badness_vector **, int *);
74 static int find_oload_champ (struct type **, int, int, int,
75 struct fn_field *, struct symbol **,
76 struct badness_vector **);
78 static int oload_method_static (int, struct fn_field *, int);
80 enum oload_classification { STANDARD, NON_STANDARD, INCOMPATIBLE };
82 static enum
83 oload_classification classify_oload_match (struct badness_vector *,
84 int, int);
86 static struct value *value_struct_elt_for_reference (struct type *,
87 int, struct type *,
88 char *,
89 struct type *,
90 int, enum noside);
92 static struct value *value_namespace_elt (const struct type *,
93 char *, int , enum noside);
95 static struct value *value_maybe_namespace_elt (const struct type *,
96 char *, int,
97 enum noside);
99 static CORE_ADDR allocate_space_in_inferior (int);
101 static struct value *cast_into_complex (struct type *, struct value *);
103 static struct fn_field *find_method_list (struct value **, const char *,
104 int, struct type *, int *,
105 struct type **, int *);
107 void _initialize_valops (void);
109 #if 0
110 /* Flag for whether we want to abandon failed expression evals by
111 default. */
113 static int auto_abandon = 0;
114 #endif
116 int overload_resolution = 0;
117 static void
118 show_overload_resolution (struct ui_file *file, int from_tty,
119 struct cmd_list_element *c,
120 const char *value)
122 fprintf_filtered (file, _("\
123 Overload resolution in evaluating C++ functions is %s.\n"),
124 value);
127 /* Find the address of function name NAME in the inferior. If OBJF_P
128 is non-NULL, *OBJF_P will be set to the OBJFILE where the function
129 is defined. */
131 struct value *
132 find_function_in_inferior (const char *name, struct objfile **objf_p)
134 struct symbol *sym;
135 sym = lookup_symbol (name, 0, VAR_DOMAIN, 0);
136 if (sym != NULL)
138 if (SYMBOL_CLASS (sym) != LOC_BLOCK)
140 error (_("\"%s\" exists in this program but is not a function."),
141 name);
144 if (objf_p)
145 *objf_p = SYMBOL_SYMTAB (sym)->objfile;
147 return value_of_variable (sym, NULL);
149 else
151 struct minimal_symbol *msymbol =
152 lookup_minimal_symbol (name, NULL, NULL);
153 if (msymbol != NULL)
155 struct objfile *objfile = msymbol_objfile (msymbol);
156 struct gdbarch *gdbarch = get_objfile_arch (objfile);
158 struct type *type;
159 CORE_ADDR maddr;
160 type = lookup_pointer_type (builtin_type (gdbarch)->builtin_char);
161 type = lookup_function_type (type);
162 type = lookup_pointer_type (type);
163 maddr = SYMBOL_VALUE_ADDRESS (msymbol);
165 if (objf_p)
166 *objf_p = objfile;
168 return value_from_pointer (type, maddr);
170 else
172 if (!target_has_execution)
173 error (_("evaluation of this expression requires the target program to be active"));
174 else
175 error (_("evaluation of this expression requires the program to have a function \"%s\"."), name);
180 /* Allocate NBYTES of space in the inferior using the inferior's
181 malloc and return a value that is a pointer to the allocated
182 space. */
184 struct value *
185 value_allocate_space_in_inferior (int len)
187 struct objfile *objf;
188 struct value *val = find_function_in_inferior ("malloc", &objf);
189 struct gdbarch *gdbarch = get_objfile_arch (objf);
190 struct value *blocklen;
192 blocklen = value_from_longest (builtin_type (gdbarch)->builtin_int, len);
193 val = call_function_by_hand (val, 1, &blocklen);
194 if (value_logical_not (val))
196 if (!target_has_execution)
197 error (_("No memory available to program now: you need to start the target first"));
198 else
199 error (_("No memory available to program: call to malloc failed"));
201 return val;
204 static CORE_ADDR
205 allocate_space_in_inferior (int len)
207 return value_as_long (value_allocate_space_in_inferior (len));
210 /* Cast struct value VAL to type TYPE and return as a value.
211 Both type and val must be of TYPE_CODE_STRUCT or TYPE_CODE_UNION
212 for this to work. Typedef to one of the codes is permitted.
213 Returns NULL if the cast is neither an upcast nor a downcast. */
215 static struct value *
216 value_cast_structs (struct type *type, struct value *v2)
218 struct type *t1;
219 struct type *t2;
220 struct value *v;
222 gdb_assert (type != NULL && v2 != NULL);
224 t1 = check_typedef (type);
225 t2 = check_typedef (value_type (v2));
227 /* Check preconditions. */
228 gdb_assert ((TYPE_CODE (t1) == TYPE_CODE_STRUCT
229 || TYPE_CODE (t1) == TYPE_CODE_UNION)
230 && !!"Precondition is that type is of STRUCT or UNION kind.");
231 gdb_assert ((TYPE_CODE (t2) == TYPE_CODE_STRUCT
232 || TYPE_CODE (t2) == TYPE_CODE_UNION)
233 && !!"Precondition is that value is of STRUCT or UNION kind");
235 if (TYPE_NAME (t1) != NULL
236 && TYPE_NAME (t2) != NULL
237 && !strcmp (TYPE_NAME (t1), TYPE_NAME (t2)))
238 return NULL;
240 /* Upcasting: look in the type of the source to see if it contains the
241 type of the target as a superclass. If so, we'll need to
242 offset the pointer rather than just change its type. */
243 if (TYPE_NAME (t1) != NULL)
245 v = search_struct_field (type_name_no_tag (t1),
246 v2, 0, t2, 1);
247 if (v)
248 return v;
251 /* Downcasting: look in the type of the target to see if it contains the
252 type of the source as a superclass. If so, we'll need to
253 offset the pointer rather than just change its type. */
254 if (TYPE_NAME (t2) != NULL)
256 /* Try downcasting using the run-time type of the value. */
257 int full, top, using_enc;
258 struct type *real_type;
260 real_type = value_rtti_type (v2, &full, &top, &using_enc);
261 if (real_type)
263 v = value_full_object (v2, real_type, full, top, using_enc);
264 v = value_at_lazy (real_type, value_address (v));
266 /* We might be trying to cast to the outermost enclosing
267 type, in which case search_struct_field won't work. */
268 if (TYPE_NAME (real_type) != NULL
269 && !strcmp (TYPE_NAME (real_type), TYPE_NAME (t1)))
270 return v;
272 v = search_struct_field (type_name_no_tag (t2), v, 0, real_type, 1);
273 if (v)
274 return v;
277 /* Try downcasting using information from the destination type
278 T2. This wouldn't work properly for classes with virtual
279 bases, but those were handled above. */
280 v = search_struct_field (type_name_no_tag (t2),
281 value_zero (t1, not_lval), 0, t1, 1);
282 if (v)
284 /* Downcasting is possible (t1 is superclass of v2). */
285 CORE_ADDR addr2 = value_address (v2);
286 addr2 -= value_address (v) + value_embedded_offset (v);
287 return value_at (type, addr2);
291 return NULL;
294 /* Cast one pointer or reference type to another. Both TYPE and
295 the type of ARG2 should be pointer types, or else both should be
296 reference types. Returns the new pointer or reference. */
298 struct value *
299 value_cast_pointers (struct type *type, struct value *arg2)
301 struct type *type1 = check_typedef (type);
302 struct type *type2 = check_typedef (value_type (arg2));
303 struct type *t1 = check_typedef (TYPE_TARGET_TYPE (type));
304 struct type *t2 = check_typedef (TYPE_TARGET_TYPE (type2));
306 if (TYPE_CODE (t1) == TYPE_CODE_STRUCT
307 && TYPE_CODE (t2) == TYPE_CODE_STRUCT
308 && !value_logical_not (arg2))
310 struct value *v2;
312 if (TYPE_CODE (type2) == TYPE_CODE_REF)
313 v2 = coerce_ref (arg2);
314 else
315 v2 = value_ind (arg2);
316 gdb_assert (TYPE_CODE (check_typedef (value_type (v2))) == TYPE_CODE_STRUCT
317 && !!"Why did coercion fail?");
318 v2 = value_cast_structs (t1, v2);
319 /* At this point we have what we can have, un-dereference if needed. */
320 if (v2)
322 struct value *v = value_addr (v2);
323 deprecated_set_value_type (v, type);
324 return v;
328 /* No superclass found, just change the pointer type. */
329 arg2 = value_copy (arg2);
330 deprecated_set_value_type (arg2, type);
331 arg2 = value_change_enclosing_type (arg2, type);
332 set_value_pointed_to_offset (arg2, 0); /* pai: chk_val */
333 return arg2;
336 /* Cast value ARG2 to type TYPE and return as a value.
337 More general than a C cast: accepts any two types of the same length,
338 and if ARG2 is an lvalue it can be cast into anything at all. */
339 /* In C++, casts may change pointer or object representations. */
341 struct value *
342 value_cast (struct type *type, struct value *arg2)
344 enum type_code code1;
345 enum type_code code2;
346 int scalar;
347 struct type *type2;
349 int convert_to_boolean = 0;
351 if (value_type (arg2) == type)
352 return arg2;
354 code1 = TYPE_CODE (check_typedef (type));
356 /* Check if we are casting struct reference to struct reference. */
357 if (code1 == TYPE_CODE_REF)
359 /* We dereference type; then we recurse and finally
360 we generate value of the given reference. Nothing wrong with
361 that. */
362 struct type *t1 = check_typedef (type);
363 struct type *dereftype = check_typedef (TYPE_TARGET_TYPE (t1));
364 struct value *val = value_cast (dereftype, arg2);
365 return value_ref (val);
368 code2 = TYPE_CODE (check_typedef (value_type (arg2)));
370 if (code2 == TYPE_CODE_REF)
371 /* We deref the value and then do the cast. */
372 return value_cast (type, coerce_ref (arg2));
374 CHECK_TYPEDEF (type);
375 code1 = TYPE_CODE (type);
376 arg2 = coerce_ref (arg2);
377 type2 = check_typedef (value_type (arg2));
379 /* You can't cast to a reference type. See value_cast_pointers
380 instead. */
381 gdb_assert (code1 != TYPE_CODE_REF);
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)
388 struct type *element_type = TYPE_TARGET_TYPE (type);
389 unsigned element_length = TYPE_LENGTH (check_typedef (element_type));
390 if (element_length > 0 && TYPE_ARRAY_UPPER_BOUND_IS_UNDEFINED (type))
392 struct type *range_type = TYPE_INDEX_TYPE (type);
393 int val_length = TYPE_LENGTH (type2);
394 LONGEST low_bound, high_bound, new_length;
395 if (get_discrete_bounds (range_type, &low_bound, &high_bound) < 0)
396 low_bound = 0, high_bound = 0;
397 new_length = val_length / element_length;
398 if (val_length % element_length != 0)
399 warning (_("array element type size does not divide object size in cast"));
400 /* FIXME-type-allocation: need a way to free this type when
401 we are done with it. */
402 range_type = create_range_type ((struct type *) NULL,
403 TYPE_TARGET_TYPE (range_type),
404 low_bound,
405 new_length + low_bound - 1);
406 deprecated_set_value_type (arg2,
407 create_array_type ((struct type *) NULL,
408 element_type,
409 range_type));
410 return arg2;
414 if (current_language->c_style_arrays
415 && TYPE_CODE (type2) == TYPE_CODE_ARRAY)
416 arg2 = value_coerce_array (arg2);
418 if (TYPE_CODE (type2) == TYPE_CODE_FUNC)
419 arg2 = value_coerce_function (arg2);
421 type2 = check_typedef (value_type (arg2));
422 code2 = TYPE_CODE (type2);
424 if (code1 == TYPE_CODE_COMPLEX)
425 return cast_into_complex (type, arg2);
426 if (code1 == TYPE_CODE_BOOL)
428 code1 = TYPE_CODE_INT;
429 convert_to_boolean = 1;
431 if (code1 == TYPE_CODE_CHAR)
432 code1 = TYPE_CODE_INT;
433 if (code2 == TYPE_CODE_BOOL || code2 == TYPE_CODE_CHAR)
434 code2 = TYPE_CODE_INT;
436 scalar = (code2 == TYPE_CODE_INT || code2 == TYPE_CODE_FLT
437 || code2 == TYPE_CODE_DECFLOAT || code2 == TYPE_CODE_ENUM
438 || code2 == TYPE_CODE_RANGE);
440 if ((code1 == TYPE_CODE_STRUCT || code1 == TYPE_CODE_UNION)
441 && (code2 == TYPE_CODE_STRUCT || code2 == TYPE_CODE_UNION)
442 && TYPE_NAME (type) != 0)
444 struct value *v = value_cast_structs (type, arg2);
445 if (v)
446 return v;
449 if (code1 == TYPE_CODE_FLT && scalar)
450 return value_from_double (type, value_as_double (arg2));
451 else if (code1 == TYPE_CODE_DECFLOAT && scalar)
453 enum bfd_endian byte_order = gdbarch_byte_order (get_type_arch (type));
454 int dec_len = TYPE_LENGTH (type);
455 gdb_byte dec[16];
457 if (code2 == TYPE_CODE_FLT)
458 decimal_from_floating (arg2, dec, dec_len, byte_order);
459 else if (code2 == TYPE_CODE_DECFLOAT)
460 decimal_convert (value_contents (arg2), TYPE_LENGTH (type2),
461 byte_order, dec, dec_len, byte_order);
462 else
463 /* The only option left is an integral type. */
464 decimal_from_integral (arg2, dec, dec_len, byte_order);
466 return value_from_decfloat (type, dec);
468 else if ((code1 == TYPE_CODE_INT || code1 == TYPE_CODE_ENUM
469 || code1 == TYPE_CODE_RANGE)
470 && (scalar || code2 == TYPE_CODE_PTR
471 || code2 == TYPE_CODE_MEMBERPTR))
473 LONGEST longest;
475 /* When we cast pointers to integers, we mustn't use
476 gdbarch_pointer_to_address to find the address the pointer
477 represents, as value_as_long would. GDB should evaluate
478 expressions just as the compiler would --- and the compiler
479 sees a cast as a simple reinterpretation of the pointer's
480 bits. */
481 if (code2 == TYPE_CODE_PTR)
482 longest = extract_unsigned_integer
483 (value_contents (arg2), TYPE_LENGTH (type2),
484 gdbarch_byte_order (get_type_arch (type2)));
485 else
486 longest = value_as_long (arg2);
487 return value_from_longest (type, convert_to_boolean ?
488 (LONGEST) (longest ? 1 : 0) : longest);
490 else if (code1 == TYPE_CODE_PTR && (code2 == TYPE_CODE_INT
491 || code2 == TYPE_CODE_ENUM
492 || code2 == TYPE_CODE_RANGE))
494 /* TYPE_LENGTH (type) is the length of a pointer, but we really
495 want the length of an address! -- we are really dealing with
496 addresses (i.e., gdb representations) not pointers (i.e.,
497 target representations) here.
499 This allows things like "print *(int *)0x01000234" to work
500 without printing a misleading message -- which would
501 otherwise occur when dealing with a target having two byte
502 pointers and four byte addresses. */
504 int addr_bit = gdbarch_addr_bit (get_type_arch (type2));
506 LONGEST longest = value_as_long (arg2);
507 if (addr_bit < sizeof (LONGEST) * HOST_CHAR_BIT)
509 if (longest >= ((LONGEST) 1 << addr_bit)
510 || longest <= -((LONGEST) 1 << addr_bit))
511 warning (_("value truncated"));
513 return value_from_longest (type, longest);
515 else if (code1 == TYPE_CODE_METHODPTR && code2 == TYPE_CODE_INT
516 && value_as_long (arg2) == 0)
518 struct value *result = allocate_value (type);
519 cplus_make_method_ptr (type, value_contents_writeable (result), 0, 0);
520 return result;
522 else if (code1 == TYPE_CODE_MEMBERPTR && code2 == TYPE_CODE_INT
523 && value_as_long (arg2) == 0)
525 /* The Itanium C++ ABI represents NULL pointers to members as
526 minus one, instead of biasing the normal case. */
527 return value_from_longest (type, -1);
529 else if (TYPE_LENGTH (type) == TYPE_LENGTH (type2))
531 if (code1 == TYPE_CODE_PTR && code2 == TYPE_CODE_PTR)
532 return value_cast_pointers (type, arg2);
534 arg2 = value_copy (arg2);
535 deprecated_set_value_type (arg2, type);
536 arg2 = value_change_enclosing_type (arg2, type);
537 set_value_pointed_to_offset (arg2, 0); /* pai: chk_val */
538 return arg2;
540 else if (VALUE_LVAL (arg2) == lval_memory)
541 return value_at_lazy (type, value_address (arg2));
542 else if (code1 == TYPE_CODE_VOID)
544 return value_zero (type, not_lval);
546 else
548 error (_("Invalid cast."));
549 return 0;
553 /* The C++ reinterpret_cast operator. */
555 struct value *
556 value_reinterpret_cast (struct type *type, struct value *arg)
558 struct value *result;
559 struct type *real_type = check_typedef (type);
560 struct type *arg_type, *dest_type;
561 int is_ref = 0;
562 enum type_code dest_code, arg_code;
564 /* Do reference, function, and array conversion. */
565 arg = coerce_array (arg);
567 /* Attempt to preserve the type the user asked for. */
568 dest_type = type;
570 /* If we are casting to a reference type, transform
571 reinterpret_cast<T&>(V) to *reinterpret_cast<T*>(&V). */
572 if (TYPE_CODE (real_type) == TYPE_CODE_REF)
574 is_ref = 1;
575 arg = value_addr (arg);
576 dest_type = lookup_pointer_type (TYPE_TARGET_TYPE (dest_type));
577 real_type = lookup_pointer_type (real_type);
580 arg_type = value_type (arg);
582 dest_code = TYPE_CODE (real_type);
583 arg_code = TYPE_CODE (arg_type);
585 /* We can convert pointer types, or any pointer type to int, or int
586 type to pointer. */
587 if ((dest_code == TYPE_CODE_PTR && arg_code == TYPE_CODE_INT)
588 || (dest_code == TYPE_CODE_INT && arg_code == TYPE_CODE_PTR)
589 || (dest_code == TYPE_CODE_METHODPTR && arg_code == TYPE_CODE_INT)
590 || (dest_code == TYPE_CODE_INT && arg_code == TYPE_CODE_METHODPTR)
591 || (dest_code == TYPE_CODE_MEMBERPTR && arg_code == TYPE_CODE_INT)
592 || (dest_code == TYPE_CODE_INT && arg_code == TYPE_CODE_MEMBERPTR)
593 || (dest_code == arg_code
594 && (dest_code == TYPE_CODE_PTR
595 || dest_code == TYPE_CODE_METHODPTR
596 || dest_code == TYPE_CODE_MEMBERPTR)))
597 result = value_cast (dest_type, arg);
598 else
599 error (_("Invalid reinterpret_cast"));
601 if (is_ref)
602 result = value_cast (type, value_ref (value_ind (result)));
604 return result;
607 /* A helper for value_dynamic_cast. This implements the first of two
608 runtime checks: we iterate over all the base classes of the value's
609 class which are equal to the desired class; if only one of these
610 holds the value, then it is the answer. */
612 static int
613 dynamic_cast_check_1 (struct type *desired_type,
614 const bfd_byte *contents,
615 CORE_ADDR address,
616 struct type *search_type,
617 CORE_ADDR arg_addr,
618 struct type *arg_type,
619 struct value **result)
621 int i, result_count = 0;
623 for (i = 0; i < TYPE_N_BASECLASSES (search_type) && result_count < 2; ++i)
625 int offset = baseclass_offset (search_type, i, contents, address);
626 if (offset == -1)
627 error (_("virtual baseclass botch"));
628 if (class_types_same_p (desired_type, TYPE_BASECLASS (search_type, i)))
630 if (address + offset >= arg_addr
631 && address + offset < arg_addr + TYPE_LENGTH (arg_type))
633 ++result_count;
634 if (!*result)
635 *result = value_at_lazy (TYPE_BASECLASS (search_type, i),
636 address + offset);
639 else
640 result_count += dynamic_cast_check_1 (desired_type,
641 contents + offset,
642 address + offset,
643 TYPE_BASECLASS (search_type, i),
644 arg_addr,
645 arg_type,
646 result);
649 return result_count;
652 /* A helper for value_dynamic_cast. This implements the second of two
653 runtime checks: we look for a unique public sibling class of the
654 argument's declared class. */
656 static int
657 dynamic_cast_check_2 (struct type *desired_type,
658 const bfd_byte *contents,
659 CORE_ADDR address,
660 struct type *search_type,
661 struct value **result)
663 int i, result_count = 0;
665 for (i = 0; i < TYPE_N_BASECLASSES (search_type) && result_count < 2; ++i)
667 int offset;
669 if (! BASETYPE_VIA_PUBLIC (search_type, i))
670 continue;
672 offset = baseclass_offset (search_type, i, contents, address);
673 if (offset == -1)
674 error (_("virtual baseclass botch"));
675 if (class_types_same_p (desired_type, TYPE_BASECLASS (search_type, i)))
677 ++result_count;
678 if (*result == NULL)
679 *result = value_at_lazy (TYPE_BASECLASS (search_type, i),
680 address + offset);
682 else
683 result_count += dynamic_cast_check_2 (desired_type,
684 contents + offset,
685 address + offset,
686 TYPE_BASECLASS (search_type, i),
687 result);
690 return result_count;
693 /* The C++ dynamic_cast operator. */
695 struct value *
696 value_dynamic_cast (struct type *type, struct value *arg)
698 int unambiguous = 0, full, top, using_enc;
699 struct type *resolved_type = check_typedef (type);
700 struct type *arg_type = check_typedef (value_type (arg));
701 struct type *class_type, *rtti_type;
702 struct value *result, *tem, *original_arg = arg;
703 CORE_ADDR addr;
704 int is_ref = TYPE_CODE (resolved_type) == TYPE_CODE_REF;
706 if (TYPE_CODE (resolved_type) != TYPE_CODE_PTR
707 && TYPE_CODE (resolved_type) != TYPE_CODE_REF)
708 error (_("Argument to dynamic_cast must be a pointer or reference type"));
709 if (TYPE_CODE (TYPE_TARGET_TYPE (resolved_type)) != TYPE_CODE_VOID
710 && TYPE_CODE (TYPE_TARGET_TYPE (resolved_type)) != TYPE_CODE_CLASS)
711 error (_("Argument to dynamic_cast must be pointer to class or `void *'"));
713 class_type = check_typedef (TYPE_TARGET_TYPE (resolved_type));
714 if (TYPE_CODE (resolved_type) == TYPE_CODE_PTR)
716 if (TYPE_CODE (arg_type) != TYPE_CODE_PTR
717 && ! (TYPE_CODE (arg_type) == TYPE_CODE_INT
718 && value_as_long (arg) == 0))
719 error (_("Argument to dynamic_cast does not have pointer type"));
720 if (TYPE_CODE (arg_type) == TYPE_CODE_PTR)
722 arg_type = check_typedef (TYPE_TARGET_TYPE (arg_type));
723 if (TYPE_CODE (arg_type) != TYPE_CODE_CLASS)
724 error (_("Argument to dynamic_cast does not have pointer to class type"));
727 /* Handle NULL pointers. */
728 if (value_as_long (arg) == 0)
729 return value_zero (type, not_lval);
731 arg = value_ind (arg);
733 else
735 if (TYPE_CODE (arg_type) != TYPE_CODE_CLASS)
736 error (_("Argument to dynamic_cast does not have class type"));
739 /* If the classes are the same, just return the argument. */
740 if (class_types_same_p (class_type, arg_type))
741 return value_cast (type, arg);
743 /* If the target type is a unique base class of the argument's
744 declared type, just cast it. */
745 if (is_ancestor (class_type, arg_type))
747 if (is_unique_ancestor (class_type, arg))
748 return value_cast (type, original_arg);
749 error (_("Ambiguous dynamic_cast"));
752 rtti_type = value_rtti_type (arg, &full, &top, &using_enc);
753 if (! rtti_type)
754 error (_("Couldn't determine value's most derived type for dynamic_cast"));
756 /* Compute the most derived object's address. */
757 addr = value_address (arg);
758 if (full)
760 /* Done. */
762 else if (using_enc)
763 addr += top;
764 else
765 addr += top + value_embedded_offset (arg);
767 /* dynamic_cast<void *> means to return a pointer to the
768 most-derived object. */
769 if (TYPE_CODE (resolved_type) == TYPE_CODE_PTR
770 && TYPE_CODE (TYPE_TARGET_TYPE (resolved_type)) == TYPE_CODE_VOID)
771 return value_at_lazy (type, addr);
773 tem = value_at (type, addr);
775 /* The first dynamic check specified in 5.2.7. */
776 if (is_public_ancestor (arg_type, TYPE_TARGET_TYPE (resolved_type)))
778 if (class_types_same_p (rtti_type, TYPE_TARGET_TYPE (resolved_type)))
779 return tem;
780 result = NULL;
781 if (dynamic_cast_check_1 (TYPE_TARGET_TYPE (resolved_type),
782 value_contents (tem), value_address (tem),
783 rtti_type, addr,
784 arg_type,
785 &result) == 1)
786 return value_cast (type,
787 is_ref ? value_ref (result) : value_addr (result));
790 /* The second dynamic check specified in 5.2.7. */
791 result = NULL;
792 if (is_public_ancestor (arg_type, rtti_type)
793 && dynamic_cast_check_2 (TYPE_TARGET_TYPE (resolved_type),
794 value_contents (tem), value_address (tem),
795 rtti_type, &result) == 1)
796 return value_cast (type,
797 is_ref ? value_ref (result) : value_addr (result));
799 if (TYPE_CODE (resolved_type) == TYPE_CODE_PTR)
800 return value_zero (type, not_lval);
802 error (_("dynamic_cast failed"));
805 /* Create a value of type TYPE that is zero, and return it. */
807 struct value *
808 value_zero (struct type *type, enum lval_type lv)
810 struct value *val = allocate_value (type);
811 VALUE_LVAL (val) = lv;
813 return val;
816 /* Create a value of numeric type TYPE that is one, and return it. */
818 struct value *
819 value_one (struct type *type, enum lval_type lv)
821 struct type *type1 = check_typedef (type);
822 struct value *val;
824 if (TYPE_CODE (type1) == TYPE_CODE_DECFLOAT)
826 enum bfd_endian byte_order = gdbarch_byte_order (get_type_arch (type));
827 gdb_byte v[16];
828 decimal_from_string (v, TYPE_LENGTH (type), byte_order, "1");
829 val = value_from_decfloat (type, v);
831 else if (TYPE_CODE (type1) == TYPE_CODE_FLT)
833 val = value_from_double (type, (DOUBLEST) 1);
835 else if (is_integral_type (type1))
837 val = value_from_longest (type, (LONGEST) 1);
839 else
841 error (_("Not a numeric type."));
844 VALUE_LVAL (val) = lv;
845 return val;
848 /* Helper function for value_at, value_at_lazy, and value_at_lazy_stack. */
850 static struct value *
851 get_value_at (struct type *type, CORE_ADDR addr, int lazy)
853 struct value *val;
855 if (TYPE_CODE (check_typedef (type)) == TYPE_CODE_VOID)
856 error (_("Attempt to dereference a generic pointer."));
858 if (lazy)
860 val = allocate_value_lazy (type);
862 else
864 val = allocate_value (type);
865 read_memory (addr, value_contents_all_raw (val), TYPE_LENGTH (type));
868 VALUE_LVAL (val) = lval_memory;
869 set_value_address (val, addr);
871 return val;
874 /* Return a value with type TYPE located at ADDR.
876 Call value_at only if the data needs to be fetched immediately;
877 if we can be 'lazy' and defer the fetch, perhaps indefinately, call
878 value_at_lazy instead. value_at_lazy simply records the address of
879 the data and sets the lazy-evaluation-required flag. The lazy flag
880 is tested in the value_contents macro, which is used if and when
881 the contents are actually required.
883 Note: value_at does *NOT* handle embedded offsets; perform such
884 adjustments before or after calling it. */
886 struct value *
887 value_at (struct type *type, CORE_ADDR addr)
889 return get_value_at (type, addr, 0);
892 /* Return a lazy value with type TYPE located at ADDR (cf. value_at). */
894 struct value *
895 value_at_lazy (struct type *type, CORE_ADDR addr)
897 return get_value_at (type, addr, 1);
900 /* Called only from the value_contents and value_contents_all()
901 macros, if the current data for a variable needs to be loaded into
902 value_contents(VAL). Fetches the data from the user's process, and
903 clears the lazy flag to indicate that the data in the buffer is
904 valid.
906 If the value is zero-length, we avoid calling read_memory, which
907 would abort. We mark the value as fetched anyway -- all 0 bytes of
910 This function returns a value because it is used in the
911 value_contents macro as part of an expression, where a void would
912 not work. The value is ignored. */
915 value_fetch_lazy (struct value *val)
917 gdb_assert (value_lazy (val));
918 allocate_value_contents (val);
919 if (value_bitsize (val))
921 /* To read a lazy bitfield, read the entire enclosing value. This
922 prevents reading the same block of (possibly volatile) memory once
923 per bitfield. It would be even better to read only the containing
924 word, but we have no way to record that just specific bits of a
925 value have been fetched. */
926 struct type *type = check_typedef (value_type (val));
927 enum bfd_endian byte_order = gdbarch_byte_order (get_type_arch (type));
928 struct value *parent = value_parent (val);
929 LONGEST offset = value_offset (val);
930 LONGEST num = unpack_bits_as_long (value_type (val),
931 value_contents (parent) + offset,
932 value_bitpos (val),
933 value_bitsize (val));
934 int length = TYPE_LENGTH (type);
935 store_signed_integer (value_contents_raw (val), length, byte_order, num);
937 else if (VALUE_LVAL (val) == lval_memory)
939 CORE_ADDR addr = value_address (val);
940 int length = TYPE_LENGTH (check_typedef (value_enclosing_type (val)));
942 if (length)
944 if (value_stack (val))
945 read_stack (addr, value_contents_all_raw (val), length);
946 else
947 read_memory (addr, value_contents_all_raw (val), length);
950 else if (VALUE_LVAL (val) == lval_register)
952 struct frame_info *frame;
953 int regnum;
954 struct type *type = check_typedef (value_type (val));
955 struct value *new_val = val, *mark = value_mark ();
957 /* Offsets are not supported here; lazy register values must
958 refer to the entire register. */
959 gdb_assert (value_offset (val) == 0);
961 while (VALUE_LVAL (new_val) == lval_register && value_lazy (new_val))
963 frame = frame_find_by_id (VALUE_FRAME_ID (new_val));
964 regnum = VALUE_REGNUM (new_val);
966 gdb_assert (frame != NULL);
968 /* Convertible register routines are used for multi-register
969 values and for interpretation in different types
970 (e.g. float or int from a double register). Lazy
971 register values should have the register's natural type,
972 so they do not apply. */
973 gdb_assert (!gdbarch_convert_register_p (get_frame_arch (frame),
974 regnum, type));
976 new_val = get_frame_register_value (frame, regnum);
979 /* If it's still lazy (for instance, a saved register on the
980 stack), fetch it. */
981 if (value_lazy (new_val))
982 value_fetch_lazy (new_val);
984 /* If the register was not saved, mark it unavailable. */
985 if (value_optimized_out (new_val))
986 set_value_optimized_out (val, 1);
987 else
988 memcpy (value_contents_raw (val), value_contents (new_val),
989 TYPE_LENGTH (type));
991 if (frame_debug)
993 struct gdbarch *gdbarch;
994 frame = frame_find_by_id (VALUE_FRAME_ID (val));
995 regnum = VALUE_REGNUM (val);
996 gdbarch = get_frame_arch (frame);
998 fprintf_unfiltered (gdb_stdlog, "\
999 { value_fetch_lazy (frame=%d,regnum=%d(%s),...) ",
1000 frame_relative_level (frame), regnum,
1001 user_reg_map_regnum_to_name (gdbarch, regnum));
1003 fprintf_unfiltered (gdb_stdlog, "->");
1004 if (value_optimized_out (new_val))
1005 fprintf_unfiltered (gdb_stdlog, " optimized out");
1006 else
1008 int i;
1009 const gdb_byte *buf = value_contents (new_val);
1011 if (VALUE_LVAL (new_val) == lval_register)
1012 fprintf_unfiltered (gdb_stdlog, " register=%d",
1013 VALUE_REGNUM (new_val));
1014 else if (VALUE_LVAL (new_val) == lval_memory)
1015 fprintf_unfiltered (gdb_stdlog, " address=%s",
1016 paddress (gdbarch,
1017 value_address (new_val)));
1018 else
1019 fprintf_unfiltered (gdb_stdlog, " computed");
1021 fprintf_unfiltered (gdb_stdlog, " bytes=");
1022 fprintf_unfiltered (gdb_stdlog, "[");
1023 for (i = 0; i < register_size (gdbarch, regnum); i++)
1024 fprintf_unfiltered (gdb_stdlog, "%02x", buf[i]);
1025 fprintf_unfiltered (gdb_stdlog, "]");
1028 fprintf_unfiltered (gdb_stdlog, " }\n");
1031 /* Dispose of the intermediate values. This prevents
1032 watchpoints from trying to watch the saved frame pointer. */
1033 value_free_to_mark (mark);
1035 else if (VALUE_LVAL (val) == lval_computed)
1036 value_computed_funcs (val)->read (val);
1037 else
1038 internal_error (__FILE__, __LINE__, "Unexpected lazy value type.");
1040 set_value_lazy (val, 0);
1041 return 0;
1045 /* Store the contents of FROMVAL into the location of TOVAL.
1046 Return a new value with the location of TOVAL and contents of FROMVAL. */
1048 struct value *
1049 value_assign (struct value *toval, struct value *fromval)
1051 struct type *type;
1052 struct value *val;
1053 struct frame_id old_frame;
1055 if (!deprecated_value_modifiable (toval))
1056 error (_("Left operand of assignment is not a modifiable lvalue."));
1058 toval = coerce_ref (toval);
1060 type = value_type (toval);
1061 if (VALUE_LVAL (toval) != lval_internalvar)
1063 toval = value_coerce_to_target (toval);
1064 fromval = value_cast (type, fromval);
1066 else
1068 /* Coerce arrays and functions to pointers, except for arrays
1069 which only live in GDB's storage. */
1070 if (!value_must_coerce_to_target (fromval))
1071 fromval = coerce_array (fromval);
1074 CHECK_TYPEDEF (type);
1076 /* Since modifying a register can trash the frame chain, and
1077 modifying memory can trash the frame cache, we save the old frame
1078 and then restore the new frame afterwards. */
1079 old_frame = get_frame_id (deprecated_safe_get_selected_frame ());
1081 switch (VALUE_LVAL (toval))
1083 case lval_internalvar:
1084 set_internalvar (VALUE_INTERNALVAR (toval), fromval);
1085 val = value_copy (fromval);
1086 val = value_change_enclosing_type (val,
1087 value_enclosing_type (fromval));
1088 set_value_embedded_offset (val, value_embedded_offset (fromval));
1089 set_value_pointed_to_offset (val,
1090 value_pointed_to_offset (fromval));
1091 return val;
1093 case lval_internalvar_component:
1094 set_internalvar_component (VALUE_INTERNALVAR (toval),
1095 value_offset (toval),
1096 value_bitpos (toval),
1097 value_bitsize (toval),
1098 fromval);
1099 break;
1101 case lval_memory:
1103 const gdb_byte *dest_buffer;
1104 CORE_ADDR changed_addr;
1105 int changed_len;
1106 gdb_byte buffer[sizeof (LONGEST)];
1108 if (value_bitsize (toval))
1110 struct value *parent = value_parent (toval);
1111 changed_addr = value_address (parent) + value_offset (toval);
1113 changed_len = (value_bitpos (toval)
1114 + value_bitsize (toval)
1115 + HOST_CHAR_BIT - 1)
1116 / HOST_CHAR_BIT;
1118 /* If we can read-modify-write exactly the size of the
1119 containing type (e.g. short or int) then do so. This
1120 is safer for volatile bitfields mapped to hardware
1121 registers. */
1122 if (changed_len < TYPE_LENGTH (type)
1123 && TYPE_LENGTH (type) <= (int) sizeof (LONGEST)
1124 && ((LONGEST) changed_addr % TYPE_LENGTH (type)) == 0)
1125 changed_len = TYPE_LENGTH (type);
1127 if (changed_len > (int) sizeof (LONGEST))
1128 error (_("Can't handle bitfields which don't fit in a %d bit word."),
1129 (int) sizeof (LONGEST) * HOST_CHAR_BIT);
1131 read_memory (changed_addr, buffer, changed_len);
1132 modify_field (type, buffer, value_as_long (fromval),
1133 value_bitpos (toval), value_bitsize (toval));
1134 dest_buffer = buffer;
1136 else
1138 changed_addr = value_address (toval);
1139 changed_len = TYPE_LENGTH (type);
1140 dest_buffer = value_contents (fromval);
1143 write_memory (changed_addr, dest_buffer, changed_len);
1144 observer_notify_memory_changed (changed_addr, changed_len,
1145 dest_buffer);
1147 break;
1149 case lval_register:
1151 struct frame_info *frame;
1152 struct gdbarch *gdbarch;
1153 int value_reg;
1155 /* Figure out which frame this is in currently. */
1156 frame = frame_find_by_id (VALUE_FRAME_ID (toval));
1157 value_reg = VALUE_REGNUM (toval);
1159 if (!frame)
1160 error (_("Value being assigned to is no longer active."));
1162 gdbarch = get_frame_arch (frame);
1163 if (gdbarch_convert_register_p (gdbarch, VALUE_REGNUM (toval), type))
1165 /* If TOVAL is a special machine register requiring
1166 conversion of program values to a special raw
1167 format. */
1168 gdbarch_value_to_register (gdbarch, frame,
1169 VALUE_REGNUM (toval), type,
1170 value_contents (fromval));
1172 else
1174 if (value_bitsize (toval))
1176 struct value *parent = value_parent (toval);
1177 int offset = value_offset (parent) + value_offset (toval);
1178 int changed_len;
1179 gdb_byte buffer[sizeof (LONGEST)];
1181 changed_len = (value_bitpos (toval)
1182 + value_bitsize (toval)
1183 + HOST_CHAR_BIT - 1)
1184 / HOST_CHAR_BIT;
1186 if (changed_len > (int) sizeof (LONGEST))
1187 error (_("Can't handle bitfields which don't fit in a %d bit word."),
1188 (int) sizeof (LONGEST) * HOST_CHAR_BIT);
1190 get_frame_register_bytes (frame, value_reg, offset,
1191 changed_len, buffer);
1193 modify_field (type, buffer, value_as_long (fromval),
1194 value_bitpos (toval), value_bitsize (toval));
1196 put_frame_register_bytes (frame, value_reg, offset,
1197 changed_len, buffer);
1199 else
1201 put_frame_register_bytes (frame, value_reg,
1202 value_offset (toval),
1203 TYPE_LENGTH (type),
1204 value_contents (fromval));
1208 if (deprecated_register_changed_hook)
1209 deprecated_register_changed_hook (-1);
1210 observer_notify_target_changed (&current_target);
1211 break;
1214 case lval_computed:
1216 struct lval_funcs *funcs = value_computed_funcs (toval);
1218 funcs->write (toval, fromval);
1220 break;
1222 default:
1223 error (_("Left operand of assignment is not an lvalue."));
1226 /* Assigning to the stack pointer, frame pointer, and other
1227 (architecture and calling convention specific) registers may
1228 cause the frame cache to be out of date. Assigning to memory
1229 also can. We just do this on all assignments to registers or
1230 memory, for simplicity's sake; I doubt the slowdown matters. */
1231 switch (VALUE_LVAL (toval))
1233 case lval_memory:
1234 case lval_register:
1236 reinit_frame_cache ();
1238 /* Having destroyed the frame cache, restore the selected
1239 frame. */
1241 /* FIXME: cagney/2002-11-02: There has to be a better way of
1242 doing this. Instead of constantly saving/restoring the
1243 frame. Why not create a get_selected_frame() function that,
1244 having saved the selected frame's ID can automatically
1245 re-find the previously selected frame automatically. */
1248 struct frame_info *fi = frame_find_by_id (old_frame);
1249 if (fi != NULL)
1250 select_frame (fi);
1253 break;
1254 default:
1255 break;
1258 /* If the field does not entirely fill a LONGEST, then zero the sign
1259 bits. If the field is signed, and is negative, then sign
1260 extend. */
1261 if ((value_bitsize (toval) > 0)
1262 && (value_bitsize (toval) < 8 * (int) sizeof (LONGEST)))
1264 LONGEST fieldval = value_as_long (fromval);
1265 LONGEST valmask = (((ULONGEST) 1) << value_bitsize (toval)) - 1;
1267 fieldval &= valmask;
1268 if (!TYPE_UNSIGNED (type)
1269 && (fieldval & (valmask ^ (valmask >> 1))))
1270 fieldval |= ~valmask;
1272 fromval = value_from_longest (type, fieldval);
1275 val = value_copy (toval);
1276 memcpy (value_contents_raw (val), value_contents (fromval),
1277 TYPE_LENGTH (type));
1278 deprecated_set_value_type (val, type);
1279 val = value_change_enclosing_type (val,
1280 value_enclosing_type (fromval));
1281 set_value_embedded_offset (val, value_embedded_offset (fromval));
1282 set_value_pointed_to_offset (val, value_pointed_to_offset (fromval));
1284 return val;
1287 /* Extend a value VAL to COUNT repetitions of its type. */
1289 struct value *
1290 value_repeat (struct value *arg1, int count)
1292 struct value *val;
1294 if (VALUE_LVAL (arg1) != lval_memory)
1295 error (_("Only values in memory can be extended with '@'."));
1296 if (count < 1)
1297 error (_("Invalid number %d of repetitions."), count);
1299 val = allocate_repeat_value (value_enclosing_type (arg1), count);
1301 read_memory (value_address (arg1),
1302 value_contents_all_raw (val),
1303 TYPE_LENGTH (value_enclosing_type (val)));
1304 VALUE_LVAL (val) = lval_memory;
1305 set_value_address (val, value_address (arg1));
1307 return val;
1310 struct value *
1311 value_of_variable (struct symbol *var, struct block *b)
1313 struct value *val;
1314 struct frame_info *frame;
1316 if (!symbol_read_needs_frame (var))
1317 frame = NULL;
1318 else if (!b)
1319 frame = get_selected_frame (_("No frame selected."));
1320 else
1322 frame = block_innermost_frame (b);
1323 if (!frame)
1325 if (BLOCK_FUNCTION (b) && !block_inlined_p (b)
1326 && SYMBOL_PRINT_NAME (BLOCK_FUNCTION (b)))
1327 error (_("No frame is currently executing in block %s."),
1328 SYMBOL_PRINT_NAME (BLOCK_FUNCTION (b)));
1329 else
1330 error (_("No frame is currently executing in specified block"));
1334 val = read_var_value (var, frame);
1335 if (!val)
1336 error (_("Address of symbol \"%s\" is unknown."), SYMBOL_PRINT_NAME (var));
1338 return val;
1341 struct value *
1342 address_of_variable (struct symbol *var, struct block *b)
1344 struct type *type = SYMBOL_TYPE (var);
1345 struct value *val;
1347 /* Evaluate it first; if the result is a memory address, we're fine.
1348 Lazy evaluation pays off here. */
1350 val = value_of_variable (var, b);
1352 if ((VALUE_LVAL (val) == lval_memory && value_lazy (val))
1353 || TYPE_CODE (type) == TYPE_CODE_FUNC)
1355 CORE_ADDR addr = value_address (val);
1356 return value_from_pointer (lookup_pointer_type (type), addr);
1359 /* Not a memory address; check what the problem was. */
1360 switch (VALUE_LVAL (val))
1362 case lval_register:
1364 struct frame_info *frame;
1365 const char *regname;
1367 frame = frame_find_by_id (VALUE_FRAME_ID (val));
1368 gdb_assert (frame);
1370 regname = gdbarch_register_name (get_frame_arch (frame),
1371 VALUE_REGNUM (val));
1372 gdb_assert (regname && *regname);
1374 error (_("Address requested for identifier "
1375 "\"%s\" which is in register $%s"),
1376 SYMBOL_PRINT_NAME (var), regname);
1377 break;
1380 default:
1381 error (_("Can't take address of \"%s\" which isn't an lvalue."),
1382 SYMBOL_PRINT_NAME (var));
1383 break;
1386 return val;
1389 /* Return one if VAL does not live in target memory, but should in order
1390 to operate on it. Otherwise return zero. */
1393 value_must_coerce_to_target (struct value *val)
1395 struct type *valtype;
1397 /* The only lval kinds which do not live in target memory. */
1398 if (VALUE_LVAL (val) != not_lval
1399 && VALUE_LVAL (val) != lval_internalvar)
1400 return 0;
1402 valtype = check_typedef (value_type (val));
1404 switch (TYPE_CODE (valtype))
1406 case TYPE_CODE_ARRAY:
1407 case TYPE_CODE_STRING:
1408 return 1;
1409 default:
1410 return 0;
1414 /* Make sure that VAL lives in target memory if it's supposed to. For instance,
1415 strings are constructed as character arrays in GDB's storage, and this
1416 function copies them to the target. */
1418 struct value *
1419 value_coerce_to_target (struct value *val)
1421 LONGEST length;
1422 CORE_ADDR addr;
1424 if (!value_must_coerce_to_target (val))
1425 return val;
1427 length = TYPE_LENGTH (check_typedef (value_type (val)));
1428 addr = allocate_space_in_inferior (length);
1429 write_memory (addr, value_contents (val), length);
1430 return value_at_lazy (value_type (val), addr);
1433 /* Given a value which is an array, return a value which is a pointer
1434 to its first element, regardless of whether or not the array has a
1435 nonzero lower bound.
1437 FIXME: A previous comment here indicated that this routine should
1438 be substracting the array's lower bound. It's not clear to me that
1439 this is correct. Given an array subscripting operation, it would
1440 certainly work to do the adjustment here, essentially computing:
1442 (&array[0] - (lowerbound * sizeof array[0])) + (index * sizeof array[0])
1444 However I believe a more appropriate and logical place to account
1445 for the lower bound is to do so in value_subscript, essentially
1446 computing:
1448 (&array[0] + ((index - lowerbound) * sizeof array[0]))
1450 As further evidence consider what would happen with operations
1451 other than array subscripting, where the caller would get back a
1452 value that had an address somewhere before the actual first element
1453 of the array, and the information about the lower bound would be
1454 lost because of the coercion to pointer type.
1457 struct value *
1458 value_coerce_array (struct value *arg1)
1460 struct type *type = check_typedef (value_type (arg1));
1462 /* If the user tries to do something requiring a pointer with an
1463 array that has not yet been pushed to the target, then this would
1464 be a good time to do so. */
1465 arg1 = value_coerce_to_target (arg1);
1467 if (VALUE_LVAL (arg1) != lval_memory)
1468 error (_("Attempt to take address of value not located in memory."));
1470 return value_from_pointer (lookup_pointer_type (TYPE_TARGET_TYPE (type)),
1471 value_address (arg1));
1474 /* Given a value which is a function, return a value which is a pointer
1475 to it. */
1477 struct value *
1478 value_coerce_function (struct value *arg1)
1480 struct value *retval;
1482 if (VALUE_LVAL (arg1) != lval_memory)
1483 error (_("Attempt to take address of value not located in memory."));
1485 retval = value_from_pointer (lookup_pointer_type (value_type (arg1)),
1486 value_address (arg1));
1487 return retval;
1490 /* Return a pointer value for the object for which ARG1 is the
1491 contents. */
1493 struct value *
1494 value_addr (struct value *arg1)
1496 struct value *arg2;
1498 struct type *type = check_typedef (value_type (arg1));
1499 if (TYPE_CODE (type) == TYPE_CODE_REF)
1501 /* Copy the value, but change the type from (T&) to (T*). We
1502 keep the same location information, which is efficient, and
1503 allows &(&X) to get the location containing the reference. */
1504 arg2 = value_copy (arg1);
1505 deprecated_set_value_type (arg2,
1506 lookup_pointer_type (TYPE_TARGET_TYPE (type)));
1507 return arg2;
1509 if (TYPE_CODE (type) == TYPE_CODE_FUNC)
1510 return value_coerce_function (arg1);
1512 /* If this is an array that has not yet been pushed to the target,
1513 then this would be a good time to force it to memory. */
1514 arg1 = value_coerce_to_target (arg1);
1516 if (VALUE_LVAL (arg1) != lval_memory)
1517 error (_("Attempt to take address of value not located in memory."));
1519 /* Get target memory address */
1520 arg2 = value_from_pointer (lookup_pointer_type (value_type (arg1)),
1521 (value_address (arg1)
1522 + value_embedded_offset (arg1)));
1524 /* This may be a pointer to a base subobject; so remember the
1525 full derived object's type ... */
1526 arg2 = value_change_enclosing_type (arg2, lookup_pointer_type (value_enclosing_type (arg1)));
1527 /* ... and also the relative position of the subobject in the full
1528 object. */
1529 set_value_pointed_to_offset (arg2, value_embedded_offset (arg1));
1530 return arg2;
1533 /* Return a reference value for the object for which ARG1 is the
1534 contents. */
1536 struct value *
1537 value_ref (struct value *arg1)
1539 struct value *arg2;
1541 struct type *type = check_typedef (value_type (arg1));
1542 if (TYPE_CODE (type) == TYPE_CODE_REF)
1543 return arg1;
1545 arg2 = value_addr (arg1);
1546 deprecated_set_value_type (arg2, lookup_reference_type (type));
1547 return arg2;
1550 /* Given a value of a pointer type, apply the C unary * operator to
1551 it. */
1553 struct value *
1554 value_ind (struct value *arg1)
1556 struct type *base_type;
1557 struct value *arg2;
1559 arg1 = coerce_array (arg1);
1561 base_type = check_typedef (value_type (arg1));
1563 if (TYPE_CODE (base_type) == TYPE_CODE_PTR)
1565 struct type *enc_type;
1566 /* We may be pointing to something embedded in a larger object.
1567 Get the real type of the enclosing object. */
1568 enc_type = check_typedef (value_enclosing_type (arg1));
1569 enc_type = TYPE_TARGET_TYPE (enc_type);
1571 if (TYPE_CODE (check_typedef (enc_type)) == TYPE_CODE_FUNC
1572 || TYPE_CODE (check_typedef (enc_type)) == TYPE_CODE_METHOD)
1573 /* For functions, go through find_function_addr, which knows
1574 how to handle function descriptors. */
1575 arg2 = value_at_lazy (enc_type,
1576 find_function_addr (arg1, NULL));
1577 else
1578 /* Retrieve the enclosing object pointed to */
1579 arg2 = value_at_lazy (enc_type,
1580 (value_as_address (arg1)
1581 - value_pointed_to_offset (arg1)));
1583 /* Re-adjust type. */
1584 deprecated_set_value_type (arg2, TYPE_TARGET_TYPE (base_type));
1585 /* Add embedding info. */
1586 arg2 = value_change_enclosing_type (arg2, enc_type);
1587 set_value_embedded_offset (arg2, value_pointed_to_offset (arg1));
1589 /* We may be pointing to an object of some derived type. */
1590 arg2 = value_full_object (arg2, NULL, 0, 0, 0);
1591 return arg2;
1594 error (_("Attempt to take contents of a non-pointer value."));
1595 return 0; /* For lint -- never reached. */
1598 /* Create a value for an array by allocating space in GDB, copying
1599 copying the data into that space, and then setting up an array
1600 value.
1602 The array bounds are set from LOWBOUND and HIGHBOUND, and the array
1603 is populated from the values passed in ELEMVEC.
1605 The element type of the array is inherited from the type of the
1606 first element, and all elements must have the same size (though we
1607 don't currently enforce any restriction on their types). */
1609 struct value *
1610 value_array (int lowbound, int highbound, struct value **elemvec)
1612 int nelem;
1613 int idx;
1614 unsigned int typelength;
1615 struct value *val;
1616 struct type *arraytype;
1617 CORE_ADDR addr;
1619 /* Validate that the bounds are reasonable and that each of the
1620 elements have the same size. */
1622 nelem = highbound - lowbound + 1;
1623 if (nelem <= 0)
1625 error (_("bad array bounds (%d, %d)"), lowbound, highbound);
1627 typelength = TYPE_LENGTH (value_enclosing_type (elemvec[0]));
1628 for (idx = 1; idx < nelem; idx++)
1630 if (TYPE_LENGTH (value_enclosing_type (elemvec[idx])) != typelength)
1632 error (_("array elements must all be the same size"));
1636 arraytype = lookup_array_range_type (value_enclosing_type (elemvec[0]),
1637 lowbound, highbound);
1639 if (!current_language->c_style_arrays)
1641 val = allocate_value (arraytype);
1642 for (idx = 0; idx < nelem; idx++)
1644 memcpy (value_contents_all_raw (val) + (idx * typelength),
1645 value_contents_all (elemvec[idx]),
1646 typelength);
1648 return val;
1651 /* Allocate space to store the array, and then initialize it by
1652 copying in each element. */
1654 val = allocate_value (arraytype);
1655 for (idx = 0; idx < nelem; idx++)
1656 memcpy (value_contents_writeable (val) + (idx * typelength),
1657 value_contents_all (elemvec[idx]),
1658 typelength);
1659 return val;
1662 struct value *
1663 value_cstring (char *ptr, int len, struct type *char_type)
1665 struct value *val;
1666 int lowbound = current_language->string_lower_bound;
1667 int highbound = len / TYPE_LENGTH (char_type);
1668 struct type *stringtype
1669 = lookup_array_range_type (char_type, lowbound, highbound + lowbound - 1);
1671 val = allocate_value (stringtype);
1672 memcpy (value_contents_raw (val), ptr, len);
1673 return val;
1676 /* Create a value for a string constant by allocating space in the
1677 inferior, copying the data into that space, and returning the
1678 address with type TYPE_CODE_STRING. PTR points to the string
1679 constant data; LEN is number of characters.
1681 Note that string types are like array of char types with a lower
1682 bound of zero and an upper bound of LEN - 1. Also note that the
1683 string may contain embedded null bytes. */
1685 struct value *
1686 value_string (char *ptr, int len, struct type *char_type)
1688 struct value *val;
1689 int lowbound = current_language->string_lower_bound;
1690 int highbound = len / TYPE_LENGTH (char_type);
1691 struct type *stringtype
1692 = lookup_string_range_type (char_type, lowbound, highbound + lowbound - 1);
1694 val = allocate_value (stringtype);
1695 memcpy (value_contents_raw (val), ptr, len);
1696 return val;
1699 struct value *
1700 value_bitstring (char *ptr, int len, struct type *index_type)
1702 struct value *val;
1703 struct type *domain_type
1704 = create_range_type (NULL, index_type, 0, len - 1);
1705 struct type *type = create_set_type (NULL, domain_type);
1706 TYPE_CODE (type) = TYPE_CODE_BITSTRING;
1707 val = allocate_value (type);
1708 memcpy (value_contents_raw (val), ptr, TYPE_LENGTH (type));
1709 return val;
1712 /* See if we can pass arguments in T2 to a function which takes
1713 arguments of types T1. T1 is a list of NARGS arguments, and T2 is
1714 a NULL-terminated vector. If some arguments need coercion of some
1715 sort, then the coerced values are written into T2. Return value is
1716 0 if the arguments could be matched, or the position at which they
1717 differ if not.
1719 STATICP is nonzero if the T1 argument list came from a static
1720 member function. T2 will still include the ``this'' pointer, but
1721 it will be skipped.
1723 For non-static member functions, we ignore the first argument,
1724 which is the type of the instance variable. This is because we
1725 want to handle calls with objects from derived classes. This is
1726 not entirely correct: we should actually check to make sure that a
1727 requested operation is type secure, shouldn't we? FIXME. */
1729 static int
1730 typecmp (int staticp, int varargs, int nargs,
1731 struct field t1[], struct value *t2[])
1733 int i;
1735 if (t2 == 0)
1736 internal_error (__FILE__, __LINE__,
1737 _("typecmp: no argument list"));
1739 /* Skip ``this'' argument if applicable. T2 will always include
1740 THIS. */
1741 if (staticp)
1742 t2 ++;
1744 for (i = 0;
1745 (i < nargs) && TYPE_CODE (t1[i].type) != TYPE_CODE_VOID;
1746 i++)
1748 struct type *tt1, *tt2;
1750 if (!t2[i])
1751 return i + 1;
1753 tt1 = check_typedef (t1[i].type);
1754 tt2 = check_typedef (value_type (t2[i]));
1756 if (TYPE_CODE (tt1) == TYPE_CODE_REF
1757 /* We should be doing hairy argument matching, as below. */
1758 && (TYPE_CODE (check_typedef (TYPE_TARGET_TYPE (tt1))) == TYPE_CODE (tt2)))
1760 if (TYPE_CODE (tt2) == TYPE_CODE_ARRAY)
1761 t2[i] = value_coerce_array (t2[i]);
1762 else
1763 t2[i] = value_ref (t2[i]);
1764 continue;
1767 /* djb - 20000715 - Until the new type structure is in the
1768 place, and we can attempt things like implicit conversions,
1769 we need to do this so you can take something like a map<const
1770 char *>, and properly access map["hello"], because the
1771 argument to [] will be a reference to a pointer to a char,
1772 and the argument will be a pointer to a char. */
1773 while (TYPE_CODE(tt1) == TYPE_CODE_REF
1774 || TYPE_CODE (tt1) == TYPE_CODE_PTR)
1776 tt1 = check_typedef( TYPE_TARGET_TYPE(tt1) );
1778 while (TYPE_CODE(tt2) == TYPE_CODE_ARRAY
1779 || TYPE_CODE(tt2) == TYPE_CODE_PTR
1780 || TYPE_CODE(tt2) == TYPE_CODE_REF)
1782 tt2 = check_typedef (TYPE_TARGET_TYPE(tt2));
1784 if (TYPE_CODE (tt1) == TYPE_CODE (tt2))
1785 continue;
1786 /* Array to pointer is a `trivial conversion' according to the
1787 ARM. */
1789 /* We should be doing much hairier argument matching (see
1790 section 13.2 of the ARM), but as a quick kludge, just check
1791 for the same type code. */
1792 if (TYPE_CODE (t1[i].type) != TYPE_CODE (value_type (t2[i])))
1793 return i + 1;
1795 if (varargs || t2[i] == NULL)
1796 return 0;
1797 return i + 1;
1800 /* Helper function used by value_struct_elt to recurse through
1801 baseclasses. Look for a field NAME in ARG1. Adjust the address of
1802 ARG1 by OFFSET bytes, and search in it assuming it has (class) type
1803 TYPE. If found, return value, else return NULL.
1805 If LOOKING_FOR_BASECLASS, then instead of looking for struct
1806 fields, look for a baseclass named NAME. */
1808 static struct value *
1809 search_struct_field (const char *name, struct value *arg1, int offset,
1810 struct type *type, int looking_for_baseclass)
1812 int i;
1813 int nbases;
1815 CHECK_TYPEDEF (type);
1816 nbases = TYPE_N_BASECLASSES (type);
1818 if (!looking_for_baseclass)
1819 for (i = TYPE_NFIELDS (type) - 1; i >= nbases; i--)
1821 char *t_field_name = TYPE_FIELD_NAME (type, i);
1823 if (t_field_name && (strcmp_iw (t_field_name, name) == 0))
1825 struct value *v;
1826 if (field_is_static (&TYPE_FIELD (type, i)))
1828 v = value_static_field (type, i);
1829 if (v == 0)
1830 error (_("field %s is nonexistent or has been optimised out"),
1831 name);
1833 else
1835 v = value_primitive_field (arg1, offset, i, type);
1836 if (v == 0)
1837 error (_("there is no field named %s"), name);
1839 return v;
1842 if (t_field_name
1843 && (t_field_name[0] == '\0'
1844 || (TYPE_CODE (type) == TYPE_CODE_UNION
1845 && (strcmp_iw (t_field_name, "else") == 0))))
1847 struct type *field_type = TYPE_FIELD_TYPE (type, i);
1848 if (TYPE_CODE (field_type) == TYPE_CODE_UNION
1849 || TYPE_CODE (field_type) == TYPE_CODE_STRUCT)
1851 /* Look for a match through the fields of an anonymous
1852 union, or anonymous struct. C++ provides anonymous
1853 unions.
1855 In the GNU Chill (now deleted from GDB)
1856 implementation of variant record types, each
1857 <alternative field> has an (anonymous) union type,
1858 each member of the union represents a <variant
1859 alternative>. Each <variant alternative> is
1860 represented as a struct, with a member for each
1861 <variant field>. */
1863 struct value *v;
1864 int new_offset = offset;
1866 /* This is pretty gross. In G++, the offset in an
1867 anonymous union is relative to the beginning of the
1868 enclosing struct. In the GNU Chill (now deleted
1869 from GDB) implementation of variant records, the
1870 bitpos is zero in an anonymous union field, so we
1871 have to add the offset of the union here. */
1872 if (TYPE_CODE (field_type) == TYPE_CODE_STRUCT
1873 || (TYPE_NFIELDS (field_type) > 0
1874 && TYPE_FIELD_BITPOS (field_type, 0) == 0))
1875 new_offset += TYPE_FIELD_BITPOS (type, i) / 8;
1877 v = search_struct_field (name, arg1, new_offset,
1878 field_type,
1879 looking_for_baseclass);
1880 if (v)
1881 return v;
1886 for (i = 0; i < nbases; i++)
1888 struct value *v;
1889 struct type *basetype = check_typedef (TYPE_BASECLASS (type, i));
1890 /* If we are looking for baseclasses, this is what we get when
1891 we hit them. But it could happen that the base part's member
1892 name is not yet filled in. */
1893 int found_baseclass = (looking_for_baseclass
1894 && TYPE_BASECLASS_NAME (type, i) != NULL
1895 && (strcmp_iw (name,
1896 TYPE_BASECLASS_NAME (type,
1897 i)) == 0));
1899 if (BASETYPE_VIA_VIRTUAL (type, i))
1901 int boffset;
1902 struct value *v2;
1904 boffset = baseclass_offset (type, i,
1905 value_contents (arg1) + offset,
1906 value_address (arg1)
1907 + value_embedded_offset (arg1)
1908 + offset);
1909 if (boffset == -1)
1910 error (_("virtual baseclass botch"));
1912 /* The virtual base class pointer might have been clobbered
1913 by the user program. Make sure that it still points to a
1914 valid memory location. */
1916 boffset += value_embedded_offset (arg1) + offset;
1917 if (boffset < 0
1918 || boffset >= TYPE_LENGTH (value_enclosing_type (arg1)))
1920 CORE_ADDR base_addr;
1922 v2 = allocate_value (basetype);
1923 base_addr = value_address (arg1) + boffset;
1924 if (target_read_memory (base_addr,
1925 value_contents_raw (v2),
1926 TYPE_LENGTH (basetype)) != 0)
1927 error (_("virtual baseclass botch"));
1928 VALUE_LVAL (v2) = lval_memory;
1929 set_value_address (v2, base_addr);
1931 else
1933 v2 = value_copy (arg1);
1934 deprecated_set_value_type (v2, basetype);
1935 set_value_embedded_offset (v2, boffset);
1938 if (found_baseclass)
1939 return v2;
1940 v = search_struct_field (name, v2, 0,
1941 TYPE_BASECLASS (type, i),
1942 looking_for_baseclass);
1944 else if (found_baseclass)
1945 v = value_primitive_field (arg1, offset, i, type);
1946 else
1947 v = search_struct_field (name, arg1,
1948 offset + TYPE_BASECLASS_BITPOS (type,
1949 i) / 8,
1950 basetype, looking_for_baseclass);
1951 if (v)
1952 return v;
1954 return NULL;
1957 /* Helper function used by value_struct_elt to recurse through
1958 baseclasses. Look for a field NAME in ARG1. Adjust the address of
1959 ARG1 by OFFSET bytes, and search in it assuming it has (class) type
1960 TYPE.
1962 If found, return value, else if name matched and args not return
1963 (value) -1, else return NULL. */
1965 static struct value *
1966 search_struct_method (const char *name, struct value **arg1p,
1967 struct value **args, int offset,
1968 int *static_memfuncp, struct type *type)
1970 int i;
1971 struct value *v;
1972 int name_matched = 0;
1973 char dem_opname[64];
1975 CHECK_TYPEDEF (type);
1976 for (i = TYPE_NFN_FIELDS (type) - 1; i >= 0; i--)
1978 char *t_field_name = TYPE_FN_FIELDLIST_NAME (type, i);
1979 /* FIXME! May need to check for ARM demangling here */
1980 if (strncmp (t_field_name, "__", 2) == 0 ||
1981 strncmp (t_field_name, "op", 2) == 0 ||
1982 strncmp (t_field_name, "type", 4) == 0)
1984 if (cplus_demangle_opname (t_field_name, dem_opname, DMGL_ANSI))
1985 t_field_name = dem_opname;
1986 else if (cplus_demangle_opname (t_field_name, dem_opname, 0))
1987 t_field_name = dem_opname;
1989 if (t_field_name && (strcmp_iw (t_field_name, name) == 0))
1991 int j = TYPE_FN_FIELDLIST_LENGTH (type, i) - 1;
1992 struct fn_field *f = TYPE_FN_FIELDLIST1 (type, i);
1993 name_matched = 1;
1995 check_stub_method_group (type, i);
1996 if (j > 0 && args == 0)
1997 error (_("cannot resolve overloaded method `%s': no arguments supplied"), name);
1998 else if (j == 0 && args == 0)
2000 v = value_fn_field (arg1p, f, j, type, offset);
2001 if (v != NULL)
2002 return v;
2004 else
2005 while (j >= 0)
2007 if (!typecmp (TYPE_FN_FIELD_STATIC_P (f, j),
2008 TYPE_VARARGS (TYPE_FN_FIELD_TYPE (f, j)),
2009 TYPE_NFIELDS (TYPE_FN_FIELD_TYPE (f, j)),
2010 TYPE_FN_FIELD_ARGS (f, j), args))
2012 if (TYPE_FN_FIELD_VIRTUAL_P (f, j))
2013 return value_virtual_fn_field (arg1p, f, j,
2014 type, offset);
2015 if (TYPE_FN_FIELD_STATIC_P (f, j)
2016 && static_memfuncp)
2017 *static_memfuncp = 1;
2018 v = value_fn_field (arg1p, f, j, type, offset);
2019 if (v != NULL)
2020 return v;
2022 j--;
2027 for (i = TYPE_N_BASECLASSES (type) - 1; i >= 0; i--)
2029 int base_offset;
2031 if (BASETYPE_VIA_VIRTUAL (type, i))
2033 struct type *baseclass = check_typedef (TYPE_BASECLASS (type, i));
2034 const gdb_byte *base_valaddr;
2036 /* The virtual base class pointer might have been
2037 clobbered by the user program. Make sure that it
2038 still points to a valid memory location. */
2040 if (offset < 0 || offset >= TYPE_LENGTH (type))
2042 gdb_byte *tmp = alloca (TYPE_LENGTH (baseclass));
2043 if (target_read_memory (value_address (*arg1p) + offset,
2044 tmp, TYPE_LENGTH (baseclass)) != 0)
2045 error (_("virtual baseclass botch"));
2046 base_valaddr = tmp;
2048 else
2049 base_valaddr = value_contents (*arg1p) + offset;
2051 base_offset = baseclass_offset (type, i, base_valaddr,
2052 value_address (*arg1p) + offset);
2053 if (base_offset == -1)
2054 error (_("virtual baseclass botch"));
2056 else
2058 base_offset = TYPE_BASECLASS_BITPOS (type, i) / 8;
2060 v = search_struct_method (name, arg1p, args, base_offset + offset,
2061 static_memfuncp, TYPE_BASECLASS (type, i));
2062 if (v == (struct value *) - 1)
2064 name_matched = 1;
2066 else if (v)
2068 /* FIXME-bothner: Why is this commented out? Why is it here? */
2069 /* *arg1p = arg1_tmp; */
2070 return v;
2073 if (name_matched)
2074 return (struct value *) - 1;
2075 else
2076 return NULL;
2079 /* Given *ARGP, a value of type (pointer to a)* structure/union,
2080 extract the component named NAME from the ultimate target
2081 structure/union and return it as a value with its appropriate type.
2082 ERR is used in the error message if *ARGP's type is wrong.
2084 C++: ARGS is a list of argument types to aid in the selection of
2085 an appropriate method. Also, handle derived types.
2087 STATIC_MEMFUNCP, if non-NULL, points to a caller-supplied location
2088 where the truthvalue of whether the function that was resolved was
2089 a static member function or not is stored.
2091 ERR is an error message to be printed in case the field is not
2092 found. */
2094 struct value *
2095 value_struct_elt (struct value **argp, struct value **args,
2096 const char *name, int *static_memfuncp, const char *err)
2098 struct type *t;
2099 struct value *v;
2101 *argp = coerce_array (*argp);
2103 t = check_typedef (value_type (*argp));
2105 /* Follow pointers until we get to a non-pointer. */
2107 while (TYPE_CODE (t) == TYPE_CODE_PTR || TYPE_CODE (t) == TYPE_CODE_REF)
2109 *argp = value_ind (*argp);
2110 /* Don't coerce fn pointer to fn and then back again! */
2111 if (TYPE_CODE (value_type (*argp)) != TYPE_CODE_FUNC)
2112 *argp = coerce_array (*argp);
2113 t = check_typedef (value_type (*argp));
2116 if (TYPE_CODE (t) != TYPE_CODE_STRUCT
2117 && TYPE_CODE (t) != TYPE_CODE_UNION)
2118 error (_("Attempt to extract a component of a value that is not a %s."), err);
2120 /* Assume it's not, unless we see that it is. */
2121 if (static_memfuncp)
2122 *static_memfuncp = 0;
2124 if (!args)
2126 /* if there are no arguments ...do this... */
2128 /* Try as a field first, because if we succeed, there is less
2129 work to be done. */
2130 v = search_struct_field (name, *argp, 0, t, 0);
2131 if (v)
2132 return v;
2134 /* C++: If it was not found as a data field, then try to
2135 return it as a pointer to a method. */
2136 v = search_struct_method (name, argp, args, 0,
2137 static_memfuncp, t);
2139 if (v == (struct value *) - 1)
2140 error (_("Cannot take address of method %s."), name);
2141 else if (v == 0)
2143 if (TYPE_NFN_FIELDS (t))
2144 error (_("There is no member or method named %s."), name);
2145 else
2146 error (_("There is no member named %s."), name);
2148 return v;
2151 v = search_struct_method (name, argp, args, 0,
2152 static_memfuncp, t);
2154 if (v == (struct value *) - 1)
2156 error (_("One of the arguments you tried to pass to %s could not be converted to what the function wants."), name);
2158 else if (v == 0)
2160 /* See if user tried to invoke data as function. If so, hand it
2161 back. If it's not callable (i.e., a pointer to function),
2162 gdb should give an error. */
2163 v = search_struct_field (name, *argp, 0, t, 0);
2164 /* If we found an ordinary field, then it is not a method call.
2165 So, treat it as if it were a static member function. */
2166 if (v && static_memfuncp)
2167 *static_memfuncp = 1;
2170 if (!v)
2171 error (_("Structure has no component named %s."), name);
2172 return v;
2175 /* Search through the methods of an object (and its bases) to find a
2176 specified method. Return the pointer to the fn_field list of
2177 overloaded instances.
2179 Helper function for value_find_oload_list.
2180 ARGP is a pointer to a pointer to a value (the object).
2181 METHOD is a string containing the method name.
2182 OFFSET is the offset within the value.
2183 TYPE is the assumed type of the object.
2184 NUM_FNS is the number of overloaded instances.
2185 BASETYPE is set to the actual type of the subobject where the
2186 method is found.
2187 BOFFSET is the offset of the base subobject where the method is found.
2190 static struct fn_field *
2191 find_method_list (struct value **argp, const char *method,
2192 int offset, struct type *type, int *num_fns,
2193 struct type **basetype, int *boffset)
2195 int i;
2196 struct fn_field *f;
2197 CHECK_TYPEDEF (type);
2199 *num_fns = 0;
2201 /* First check in object itself. */
2202 for (i = TYPE_NFN_FIELDS (type) - 1; i >= 0; i--)
2204 /* pai: FIXME What about operators and type conversions? */
2205 char *fn_field_name = TYPE_FN_FIELDLIST_NAME (type, i);
2206 if (fn_field_name && (strcmp_iw (fn_field_name, method) == 0))
2208 int len = TYPE_FN_FIELDLIST_LENGTH (type, i);
2209 struct fn_field *f = TYPE_FN_FIELDLIST1 (type, i);
2211 *num_fns = len;
2212 *basetype = type;
2213 *boffset = offset;
2215 /* Resolve any stub methods. */
2216 check_stub_method_group (type, i);
2218 return f;
2222 /* Not found in object, check in base subobjects. */
2223 for (i = TYPE_N_BASECLASSES (type) - 1; i >= 0; i--)
2225 int base_offset;
2226 if (BASETYPE_VIA_VIRTUAL (type, i))
2228 base_offset = value_offset (*argp) + offset;
2229 base_offset = baseclass_offset (type, i,
2230 value_contents (*argp) + base_offset,
2231 value_address (*argp) + base_offset);
2232 if (base_offset == -1)
2233 error (_("virtual baseclass botch"));
2235 else /* Non-virtual base, simply use bit position from debug
2236 info. */
2238 base_offset = TYPE_BASECLASS_BITPOS (type, i) / 8;
2240 f = find_method_list (argp, method, base_offset + offset,
2241 TYPE_BASECLASS (type, i), num_fns,
2242 basetype, boffset);
2243 if (f)
2244 return f;
2246 return NULL;
2249 /* Return the list of overloaded methods of a specified name.
2251 ARGP is a pointer to a pointer to a value (the object).
2252 METHOD is the method name.
2253 OFFSET is the offset within the value contents.
2254 NUM_FNS is the number of overloaded instances.
2255 BASETYPE is set to the type of the base subobject that defines the
2256 method.
2257 BOFFSET is the offset of the base subobject which defines the method.
2260 struct fn_field *
2261 value_find_oload_method_list (struct value **argp, const char *method,
2262 int offset, int *num_fns,
2263 struct type **basetype, int *boffset)
2265 struct type *t;
2267 t = check_typedef (value_type (*argp));
2269 /* Code snarfed from value_struct_elt. */
2270 while (TYPE_CODE (t) == TYPE_CODE_PTR || TYPE_CODE (t) == TYPE_CODE_REF)
2272 *argp = value_ind (*argp);
2273 /* Don't coerce fn pointer to fn and then back again! */
2274 if (TYPE_CODE (value_type (*argp)) != TYPE_CODE_FUNC)
2275 *argp = coerce_array (*argp);
2276 t = check_typedef (value_type (*argp));
2279 if (TYPE_CODE (t) != TYPE_CODE_STRUCT
2280 && TYPE_CODE (t) != TYPE_CODE_UNION)
2281 error (_("Attempt to extract a component of a value that is not a struct or union"));
2283 return find_method_list (argp, method, 0, t, num_fns,
2284 basetype, boffset);
2287 /* Given an array of argument types (ARGTYPES) (which includes an
2288 entry for "this" in the case of C++ methods), the number of
2289 arguments NARGS, the NAME of a function whether it's a method or
2290 not (METHOD), and the degree of laxness (LAX) in conforming to
2291 overload resolution rules in ANSI C++, find the best function that
2292 matches on the argument types according to the overload resolution
2293 rules.
2295 In the case of class methods, the parameter OBJ is an object value
2296 in which to search for overloaded methods.
2298 In the case of non-method functions, the parameter FSYM is a symbol
2299 corresponding to one of the overloaded functions.
2301 Return value is an integer: 0 -> good match, 10 -> debugger applied
2302 non-standard coercions, 100 -> incompatible.
2304 If a method is being searched for, VALP will hold the value.
2305 If a non-method is being searched for, SYMP will hold the symbol
2306 for it.
2308 If a method is being searched for, and it is a static method,
2309 then STATICP will point to a non-zero value.
2311 Note: This function does *not* check the value of
2312 overload_resolution. Caller must check it to see whether overload
2313 resolution is permitted.
2317 find_overload_match (struct type **arg_types, int nargs,
2318 const char *name, int method, int lax,
2319 struct value **objp, struct symbol *fsym,
2320 struct value **valp, struct symbol **symp,
2321 int *staticp)
2323 struct value *obj = (objp ? *objp : NULL);
2324 /* Index of best overloaded function. */
2325 int oload_champ;
2326 /* The measure for the current best match. */
2327 struct badness_vector *oload_champ_bv = NULL;
2328 struct value *temp = obj;
2329 /* For methods, the list of overloaded methods. */
2330 struct fn_field *fns_ptr = NULL;
2331 /* For non-methods, the list of overloaded function symbols. */
2332 struct symbol **oload_syms = NULL;
2333 /* Number of overloaded instances being considered. */
2334 int num_fns = 0;
2335 struct type *basetype = NULL;
2336 int boffset;
2337 int ix;
2338 int static_offset;
2339 struct cleanup *old_cleanups = NULL;
2341 const char *obj_type_name = NULL;
2342 char *func_name = NULL;
2343 enum oload_classification match_quality;
2345 /* Get the list of overloaded methods or functions. */
2346 if (method)
2348 gdb_assert (obj);
2349 obj_type_name = TYPE_NAME (value_type (obj));
2350 /* Hack: evaluate_subexp_standard often passes in a pointer
2351 value rather than the object itself, so try again. */
2352 if ((!obj_type_name || !*obj_type_name)
2353 && (TYPE_CODE (value_type (obj)) == TYPE_CODE_PTR))
2354 obj_type_name = TYPE_NAME (TYPE_TARGET_TYPE (value_type (obj)));
2356 fns_ptr = value_find_oload_method_list (&temp, name,
2357 0, &num_fns,
2358 &basetype, &boffset);
2359 if (!fns_ptr || !num_fns)
2360 error (_("Couldn't find method %s%s%s"),
2361 obj_type_name,
2362 (obj_type_name && *obj_type_name) ? "::" : "",
2363 name);
2364 /* If we are dealing with stub method types, they should have
2365 been resolved by find_method_list via
2366 value_find_oload_method_list above. */
2367 gdb_assert (TYPE_DOMAIN_TYPE (fns_ptr[0].type) != NULL);
2368 oload_champ = find_oload_champ (arg_types, nargs, method,
2369 num_fns, fns_ptr,
2370 oload_syms, &oload_champ_bv);
2372 else
2374 const char *qualified_name = SYMBOL_CPLUS_DEMANGLED_NAME (fsym);
2376 /* If we have a C++ name, try to extract just the function
2377 part. */
2378 if (qualified_name)
2379 func_name = cp_func_name (qualified_name);
2381 /* If there was no C++ name, this must be a C-style function.
2382 Just return the same symbol. Do the same if cp_func_name
2383 fails for some reason. */
2384 if (func_name == NULL)
2386 *symp = fsym;
2387 return 0;
2390 old_cleanups = make_cleanup (xfree, func_name);
2391 make_cleanup (xfree, oload_syms);
2392 make_cleanup (xfree, oload_champ_bv);
2394 oload_champ = find_oload_champ_namespace (arg_types, nargs,
2395 func_name,
2396 qualified_name,
2397 &oload_syms,
2398 &oload_champ_bv);
2401 /* Check how bad the best match is. */
2403 match_quality =
2404 classify_oload_match (oload_champ_bv, nargs,
2405 oload_method_static (method, fns_ptr,
2406 oload_champ));
2408 if (match_quality == INCOMPATIBLE)
2410 if (method)
2411 error (_("Cannot resolve method %s%s%s to any overloaded instance"),
2412 obj_type_name,
2413 (obj_type_name && *obj_type_name) ? "::" : "",
2414 name);
2415 else
2416 error (_("Cannot resolve function %s to any overloaded instance"),
2417 func_name);
2419 else if (match_quality == NON_STANDARD)
2421 if (method)
2422 warning (_("Using non-standard conversion to match method %s%s%s to supplied arguments"),
2423 obj_type_name,
2424 (obj_type_name && *obj_type_name) ? "::" : "",
2425 name);
2426 else
2427 warning (_("Using non-standard conversion to match function %s to supplied arguments"),
2428 func_name);
2431 if (method)
2433 if (staticp != NULL)
2434 *staticp = oload_method_static (method, fns_ptr, oload_champ);
2435 if (TYPE_FN_FIELD_VIRTUAL_P (fns_ptr, oload_champ))
2436 *valp = value_virtual_fn_field (&temp, fns_ptr, oload_champ,
2437 basetype, boffset);
2438 else
2439 *valp = value_fn_field (&temp, fns_ptr, oload_champ,
2440 basetype, boffset);
2442 else
2444 *symp = oload_syms[oload_champ];
2447 if (objp)
2449 struct type *temp_type = check_typedef (value_type (temp));
2450 struct type *obj_type = check_typedef (value_type (*objp));
2451 if (TYPE_CODE (temp_type) != TYPE_CODE_PTR
2452 && (TYPE_CODE (obj_type) == TYPE_CODE_PTR
2453 || TYPE_CODE (obj_type) == TYPE_CODE_REF))
2455 temp = value_addr (temp);
2457 *objp = temp;
2459 if (old_cleanups != NULL)
2460 do_cleanups (old_cleanups);
2462 switch (match_quality)
2464 case INCOMPATIBLE:
2465 return 100;
2466 case NON_STANDARD:
2467 return 10;
2468 default: /* STANDARD */
2469 return 0;
2473 /* Find the best overload match, searching for FUNC_NAME in namespaces
2474 contained in QUALIFIED_NAME until it either finds a good match or
2475 runs out of namespaces. It stores the overloaded functions in
2476 *OLOAD_SYMS, and the badness vector in *OLOAD_CHAMP_BV. The
2477 calling function is responsible for freeing *OLOAD_SYMS and
2478 *OLOAD_CHAMP_BV. */
2480 static int
2481 find_oload_champ_namespace (struct type **arg_types, int nargs,
2482 const char *func_name,
2483 const char *qualified_name,
2484 struct symbol ***oload_syms,
2485 struct badness_vector **oload_champ_bv)
2487 int oload_champ;
2489 find_oload_champ_namespace_loop (arg_types, nargs,
2490 func_name,
2491 qualified_name, 0,
2492 oload_syms, oload_champ_bv,
2493 &oload_champ);
2495 return oload_champ;
2498 /* Helper function for find_oload_champ_namespace; NAMESPACE_LEN is
2499 how deep we've looked for namespaces, and the champ is stored in
2500 OLOAD_CHAMP. The return value is 1 if the champ is a good one, 0
2501 if it isn't.
2503 It is the caller's responsibility to free *OLOAD_SYMS and
2504 *OLOAD_CHAMP_BV. */
2506 static int
2507 find_oload_champ_namespace_loop (struct type **arg_types, int nargs,
2508 const char *func_name,
2509 const char *qualified_name,
2510 int namespace_len,
2511 struct symbol ***oload_syms,
2512 struct badness_vector **oload_champ_bv,
2513 int *oload_champ)
2515 int next_namespace_len = namespace_len;
2516 int searched_deeper = 0;
2517 int num_fns = 0;
2518 struct cleanup *old_cleanups;
2519 int new_oload_champ;
2520 struct symbol **new_oload_syms;
2521 struct badness_vector *new_oload_champ_bv;
2522 char *new_namespace;
2524 if (next_namespace_len != 0)
2526 gdb_assert (qualified_name[next_namespace_len] == ':');
2527 next_namespace_len += 2;
2529 next_namespace_len +=
2530 cp_find_first_component (qualified_name + next_namespace_len);
2532 /* Initialize these to values that can safely be xfree'd. */
2533 *oload_syms = NULL;
2534 *oload_champ_bv = NULL;
2536 /* First, see if we have a deeper namespace we can search in.
2537 If we get a good match there, use it. */
2539 if (qualified_name[next_namespace_len] == ':')
2541 searched_deeper = 1;
2543 if (find_oload_champ_namespace_loop (arg_types, nargs,
2544 func_name, qualified_name,
2545 next_namespace_len,
2546 oload_syms, oload_champ_bv,
2547 oload_champ))
2549 return 1;
2553 /* If we reach here, either we're in the deepest namespace or we
2554 didn't find a good match in a deeper namespace. But, in the
2555 latter case, we still have a bad match in a deeper namespace;
2556 note that we might not find any match at all in the current
2557 namespace. (There's always a match in the deepest namespace,
2558 because this overload mechanism only gets called if there's a
2559 function symbol to start off with.) */
2561 old_cleanups = make_cleanup (xfree, *oload_syms);
2562 old_cleanups = make_cleanup (xfree, *oload_champ_bv);
2563 new_namespace = alloca (namespace_len + 1);
2564 strncpy (new_namespace, qualified_name, namespace_len);
2565 new_namespace[namespace_len] = '\0';
2566 new_oload_syms = make_symbol_overload_list (func_name,
2567 new_namespace);
2568 while (new_oload_syms[num_fns])
2569 ++num_fns;
2571 new_oload_champ = find_oload_champ (arg_types, nargs, 0, num_fns,
2572 NULL, new_oload_syms,
2573 &new_oload_champ_bv);
2575 /* Case 1: We found a good match. Free earlier matches (if any),
2576 and return it. Case 2: We didn't find a good match, but we're
2577 not the deepest function. Then go with the bad match that the
2578 deeper function found. Case 3: We found a bad match, and we're
2579 the deepest function. Then return what we found, even though
2580 it's a bad match. */
2582 if (new_oload_champ != -1
2583 && classify_oload_match (new_oload_champ_bv, nargs, 0) == STANDARD)
2585 *oload_syms = new_oload_syms;
2586 *oload_champ = new_oload_champ;
2587 *oload_champ_bv = new_oload_champ_bv;
2588 do_cleanups (old_cleanups);
2589 return 1;
2591 else if (searched_deeper)
2593 xfree (new_oload_syms);
2594 xfree (new_oload_champ_bv);
2595 discard_cleanups (old_cleanups);
2596 return 0;
2598 else
2600 gdb_assert (new_oload_champ != -1);
2601 *oload_syms = new_oload_syms;
2602 *oload_champ = new_oload_champ;
2603 *oload_champ_bv = new_oload_champ_bv;
2604 discard_cleanups (old_cleanups);
2605 return 0;
2609 /* Look for a function to take NARGS args of types ARG_TYPES. Find
2610 the best match from among the overloaded methods or functions
2611 (depending on METHOD) given by FNS_PTR or OLOAD_SYMS, respectively.
2612 The number of methods/functions in the list is given by NUM_FNS.
2613 Return the index of the best match; store an indication of the
2614 quality of the match in OLOAD_CHAMP_BV.
2616 It is the caller's responsibility to free *OLOAD_CHAMP_BV. */
2618 static int
2619 find_oload_champ (struct type **arg_types, int nargs, int method,
2620 int num_fns, struct fn_field *fns_ptr,
2621 struct symbol **oload_syms,
2622 struct badness_vector **oload_champ_bv)
2624 int ix;
2625 /* A measure of how good an overloaded instance is. */
2626 struct badness_vector *bv;
2627 /* Index of best overloaded function. */
2628 int oload_champ = -1;
2629 /* Current ambiguity state for overload resolution. */
2630 int oload_ambiguous = 0;
2631 /* 0 => no ambiguity, 1 => two good funcs, 2 => incomparable funcs. */
2633 *oload_champ_bv = NULL;
2635 /* Consider each candidate in turn. */
2636 for (ix = 0; ix < num_fns; ix++)
2638 int jj;
2639 int static_offset = oload_method_static (method, fns_ptr, ix);
2640 int nparms;
2641 struct type **parm_types;
2643 if (method)
2645 nparms = TYPE_NFIELDS (TYPE_FN_FIELD_TYPE (fns_ptr, ix));
2647 else
2649 /* If it's not a method, this is the proper place. */
2650 nparms = TYPE_NFIELDS (SYMBOL_TYPE (oload_syms[ix]));
2653 /* Prepare array of parameter types. */
2654 parm_types = (struct type **)
2655 xmalloc (nparms * (sizeof (struct type *)));
2656 for (jj = 0; jj < nparms; jj++)
2657 parm_types[jj] = (method
2658 ? (TYPE_FN_FIELD_ARGS (fns_ptr, ix)[jj].type)
2659 : TYPE_FIELD_TYPE (SYMBOL_TYPE (oload_syms[ix]),
2660 jj));
2662 /* Compare parameter types to supplied argument types. Skip
2663 THIS for static methods. */
2664 bv = rank_function (parm_types, nparms,
2665 arg_types + static_offset,
2666 nargs - static_offset);
2668 if (!*oload_champ_bv)
2670 *oload_champ_bv = bv;
2671 oload_champ = 0;
2673 else /* See whether current candidate is better or worse than
2674 previous best. */
2675 switch (compare_badness (bv, *oload_champ_bv))
2677 case 0: /* Top two contenders are equally good. */
2678 oload_ambiguous = 1;
2679 break;
2680 case 1: /* Incomparable top contenders. */
2681 oload_ambiguous = 2;
2682 break;
2683 case 2: /* New champion, record details. */
2684 *oload_champ_bv = bv;
2685 oload_ambiguous = 0;
2686 oload_champ = ix;
2687 break;
2688 case 3:
2689 default:
2690 break;
2692 xfree (parm_types);
2693 if (overload_debug)
2695 if (method)
2696 fprintf_filtered (gdb_stderr,
2697 "Overloaded method instance %s, # of parms %d\n",
2698 fns_ptr[ix].physname, nparms);
2699 else
2700 fprintf_filtered (gdb_stderr,
2701 "Overloaded function instance %s # of parms %d\n",
2702 SYMBOL_DEMANGLED_NAME (oload_syms[ix]),
2703 nparms);
2704 for (jj = 0; jj < nargs - static_offset; jj++)
2705 fprintf_filtered (gdb_stderr,
2706 "...Badness @ %d : %d\n",
2707 jj, bv->rank[jj]);
2708 fprintf_filtered (gdb_stderr,
2709 "Overload resolution champion is %d, ambiguous? %d\n",
2710 oload_champ, oload_ambiguous);
2714 return oload_champ;
2717 /* Return 1 if we're looking at a static method, 0 if we're looking at
2718 a non-static method or a function that isn't a method. */
2720 static int
2721 oload_method_static (int method, struct fn_field *fns_ptr, int index)
2723 if (method && TYPE_FN_FIELD_STATIC_P (fns_ptr, index))
2724 return 1;
2725 else
2726 return 0;
2729 /* Check how good an overload match OLOAD_CHAMP_BV represents. */
2731 static enum oload_classification
2732 classify_oload_match (struct badness_vector *oload_champ_bv,
2733 int nargs,
2734 int static_offset)
2736 int ix;
2738 for (ix = 1; ix <= nargs - static_offset; ix++)
2740 if (oload_champ_bv->rank[ix] >= 100)
2741 return INCOMPATIBLE; /* Truly mismatched types. */
2742 else if (oload_champ_bv->rank[ix] >= 10)
2743 return NON_STANDARD; /* Non-standard type conversions
2744 needed. */
2747 return STANDARD; /* Only standard conversions needed. */
2750 /* C++: return 1 is NAME is a legitimate name for the destructor of
2751 type TYPE. If TYPE does not have a destructor, or if NAME is
2752 inappropriate for TYPE, an error is signaled. */
2754 destructor_name_p (const char *name, const struct type *type)
2756 if (name[0] == '~')
2758 char *dname = type_name_no_tag (type);
2759 char *cp = strchr (dname, '<');
2760 unsigned int len;
2762 /* Do not compare the template part for template classes. */
2763 if (cp == NULL)
2764 len = strlen (dname);
2765 else
2766 len = cp - dname;
2767 if (strlen (name + 1) != len || strncmp (dname, name + 1, len) != 0)
2768 error (_("name of destructor must equal name of class"));
2769 else
2770 return 1;
2772 return 0;
2775 /* Given TYPE, a structure/union,
2776 return 1 if the component named NAME from the ultimate target
2777 structure/union is defined, otherwise, return 0. */
2780 check_field (struct type *type, const char *name)
2782 int i;
2784 /* The type may be a stub. */
2785 CHECK_TYPEDEF (type);
2787 for (i = TYPE_NFIELDS (type) - 1; i >= TYPE_N_BASECLASSES (type); i--)
2789 char *t_field_name = TYPE_FIELD_NAME (type, i);
2790 if (t_field_name && (strcmp_iw (t_field_name, name) == 0))
2791 return 1;
2794 /* C++: If it was not found as a data field, then try to return it
2795 as a pointer to a method. */
2797 for (i = TYPE_NFN_FIELDS (type) - 1; i >= 0; --i)
2799 if (strcmp_iw (TYPE_FN_FIELDLIST_NAME (type, i), name) == 0)
2800 return 1;
2803 for (i = TYPE_N_BASECLASSES (type) - 1; i >= 0; i--)
2804 if (check_field (TYPE_BASECLASS (type, i), name))
2805 return 1;
2807 return 0;
2810 /* C++: Given an aggregate type CURTYPE, and a member name NAME,
2811 return the appropriate member (or the address of the member, if
2812 WANT_ADDRESS). This function is used to resolve user expressions
2813 of the form "DOMAIN::NAME". For more details on what happens, see
2814 the comment before value_struct_elt_for_reference. */
2816 struct value *
2817 value_aggregate_elt (struct type *curtype, char *name,
2818 struct type *expect_type, int want_address,
2819 enum noside noside)
2821 switch (TYPE_CODE (curtype))
2823 case TYPE_CODE_STRUCT:
2824 case TYPE_CODE_UNION:
2825 return value_struct_elt_for_reference (curtype, 0, curtype,
2826 name, expect_type,
2827 want_address, noside);
2828 case TYPE_CODE_NAMESPACE:
2829 return value_namespace_elt (curtype, name,
2830 want_address, noside);
2831 default:
2832 internal_error (__FILE__, __LINE__,
2833 _("non-aggregate type in value_aggregate_elt"));
2837 /* Compares the two method/function types T1 and T2 for "equality"
2838 with respect to the the methods' parameters. If the types of the
2839 two parameter lists are the same, returns 1; 0 otherwise. This
2840 comparison may ignore any artificial parameters in T1 if
2841 SKIP_ARTIFICIAL is non-zero. This function will ALWAYS skip
2842 the first artificial parameter in T1, assumed to be a 'this' pointer.
2844 The type T2 is expected to have come from make_params (in eval.c). */
2846 static int
2847 compare_parameters (struct type *t1, struct type *t2, int skip_artificial)
2849 int start = 0;
2851 if (TYPE_FIELD_ARTIFICIAL (t1, 0))
2852 ++start;
2854 /* If skipping artificial fields, find the first real field
2855 in T1. */
2856 if (skip_artificial)
2858 while (start < TYPE_NFIELDS (t1)
2859 && TYPE_FIELD_ARTIFICIAL (t1, start))
2860 ++start;
2863 /* Now compare parameters */
2865 /* Special case: a method taking void. T1 will contain no
2866 non-artificial fields, and T2 will contain TYPE_CODE_VOID. */
2867 if ((TYPE_NFIELDS (t1) - start) == 0 && TYPE_NFIELDS (t2) == 1
2868 && TYPE_CODE (TYPE_FIELD_TYPE (t2, 0)) == TYPE_CODE_VOID)
2869 return 1;
2871 if ((TYPE_NFIELDS (t1) - start) == TYPE_NFIELDS (t2))
2873 int i;
2874 for (i = 0; i < TYPE_NFIELDS (t2); ++i)
2876 if (rank_one_type (TYPE_FIELD_TYPE (t1, start + i),
2877 TYPE_FIELD_TYPE (t2, i))
2878 != 0)
2879 return 0;
2882 return 1;
2885 return 0;
2888 /* C++: Given an aggregate type CURTYPE, and a member name NAME,
2889 return the address of this member as a "pointer to member" type.
2890 If INTYPE is non-null, then it will be the type of the member we
2891 are looking for. This will help us resolve "pointers to member
2892 functions". This function is used to resolve user expressions of
2893 the form "DOMAIN::NAME". */
2895 static struct value *
2896 value_struct_elt_for_reference (struct type *domain, int offset,
2897 struct type *curtype, char *name,
2898 struct type *intype,
2899 int want_address,
2900 enum noside noside)
2902 struct type *t = curtype;
2903 int i;
2904 struct value *v, *result;
2906 if (TYPE_CODE (t) != TYPE_CODE_STRUCT
2907 && TYPE_CODE (t) != TYPE_CODE_UNION)
2908 error (_("Internal error: non-aggregate type to value_struct_elt_for_reference"));
2910 for (i = TYPE_NFIELDS (t) - 1; i >= TYPE_N_BASECLASSES (t); i--)
2912 char *t_field_name = TYPE_FIELD_NAME (t, i);
2914 if (t_field_name && strcmp (t_field_name, name) == 0)
2916 if (field_is_static (&TYPE_FIELD (t, i)))
2918 v = value_static_field (t, i);
2919 if (v == NULL)
2920 error (_("static field %s has been optimized out"),
2921 name);
2922 if (want_address)
2923 v = value_addr (v);
2924 return v;
2926 if (TYPE_FIELD_PACKED (t, i))
2927 error (_("pointers to bitfield members not allowed"));
2929 if (want_address)
2930 return value_from_longest
2931 (lookup_memberptr_type (TYPE_FIELD_TYPE (t, i), domain),
2932 offset + (LONGEST) (TYPE_FIELD_BITPOS (t, i) >> 3));
2933 else if (noside == EVAL_AVOID_SIDE_EFFECTS)
2934 return allocate_value (TYPE_FIELD_TYPE (t, i));
2935 else
2936 error (_("Cannot reference non-static field \"%s\""), name);
2940 /* C++: If it was not found as a data field, then try to return it
2941 as a pointer to a method. */
2943 /* Perform all necessary dereferencing. */
2944 while (intype && TYPE_CODE (intype) == TYPE_CODE_PTR)
2945 intype = TYPE_TARGET_TYPE (intype);
2947 for (i = TYPE_NFN_FIELDS (t) - 1; i >= 0; --i)
2949 char *t_field_name = TYPE_FN_FIELDLIST_NAME (t, i);
2950 char dem_opname[64];
2952 if (strncmp (t_field_name, "__", 2) == 0
2953 || strncmp (t_field_name, "op", 2) == 0
2954 || strncmp (t_field_name, "type", 4) == 0)
2956 if (cplus_demangle_opname (t_field_name,
2957 dem_opname, DMGL_ANSI))
2958 t_field_name = dem_opname;
2959 else if (cplus_demangle_opname (t_field_name,
2960 dem_opname, 0))
2961 t_field_name = dem_opname;
2963 if (t_field_name && strcmp (t_field_name, name) == 0)
2965 int j;
2966 int len = TYPE_FN_FIELDLIST_LENGTH (t, i);
2967 struct fn_field *f = TYPE_FN_FIELDLIST1 (t, i);
2969 check_stub_method_group (t, i);
2971 if (intype)
2973 for (j = 0; j < len; ++j)
2975 if (compare_parameters (TYPE_FN_FIELD_TYPE (f, j), intype, 0)
2976 || compare_parameters (TYPE_FN_FIELD_TYPE (f, j), intype, 1))
2977 break;
2980 if (j == len)
2981 error (_("no member function matches that type instantiation"));
2983 else
2985 int ii;
2987 j = -1;
2988 for (ii = 0; ii < TYPE_FN_FIELDLIST_LENGTH (t, i);
2989 ++ii)
2991 /* Skip artificial methods. This is necessary if,
2992 for example, the user wants to "print
2993 subclass::subclass" with only one user-defined
2994 constructor. There is no ambiguity in this
2995 case. */
2996 if (TYPE_FN_FIELD_ARTIFICIAL (f, ii))
2997 continue;
2999 /* Desired method is ambiguous if more than one
3000 method is defined. */
3001 if (j != -1)
3002 error (_("non-unique member `%s' requires type instantiation"), name);
3004 j = ii;
3008 if (TYPE_FN_FIELD_STATIC_P (f, j))
3010 struct symbol *s =
3011 lookup_symbol (TYPE_FN_FIELD_PHYSNAME (f, j),
3012 0, VAR_DOMAIN, 0);
3013 if (s == NULL)
3014 return NULL;
3016 if (want_address)
3017 return value_addr (read_var_value (s, 0));
3018 else
3019 return read_var_value (s, 0);
3022 if (TYPE_FN_FIELD_VIRTUAL_P (f, j))
3024 if (want_address)
3026 result = allocate_value
3027 (lookup_methodptr_type (TYPE_FN_FIELD_TYPE (f, j)));
3028 cplus_make_method_ptr (value_type (result),
3029 value_contents_writeable (result),
3030 TYPE_FN_FIELD_VOFFSET (f, j), 1);
3032 else if (noside == EVAL_AVOID_SIDE_EFFECTS)
3033 return allocate_value (TYPE_FN_FIELD_TYPE (f, j));
3034 else
3035 error (_("Cannot reference virtual member function \"%s\""),
3036 name);
3038 else
3040 struct symbol *s =
3041 lookup_symbol (TYPE_FN_FIELD_PHYSNAME (f, j),
3042 0, VAR_DOMAIN, 0);
3043 if (s == NULL)
3044 return NULL;
3046 v = read_var_value (s, 0);
3047 if (!want_address)
3048 result = v;
3049 else
3051 result = allocate_value (lookup_methodptr_type (TYPE_FN_FIELD_TYPE (f, j)));
3052 cplus_make_method_ptr (value_type (result),
3053 value_contents_writeable (result),
3054 value_address (v), 0);
3057 return result;
3060 for (i = TYPE_N_BASECLASSES (t) - 1; i >= 0; i--)
3062 struct value *v;
3063 int base_offset;
3065 if (BASETYPE_VIA_VIRTUAL (t, i))
3066 base_offset = 0;
3067 else
3068 base_offset = TYPE_BASECLASS_BITPOS (t, i) / 8;
3069 v = value_struct_elt_for_reference (domain,
3070 offset + base_offset,
3071 TYPE_BASECLASS (t, i),
3072 name, intype,
3073 want_address, noside);
3074 if (v)
3075 return v;
3078 /* As a last chance, pretend that CURTYPE is a namespace, and look
3079 it up that way; this (frequently) works for types nested inside
3080 classes. */
3082 return value_maybe_namespace_elt (curtype, name,
3083 want_address, noside);
3086 /* C++: Return the member NAME of the namespace given by the type
3087 CURTYPE. */
3089 static struct value *
3090 value_namespace_elt (const struct type *curtype,
3091 char *name, int want_address,
3092 enum noside noside)
3094 struct value *retval = value_maybe_namespace_elt (curtype, name,
3095 want_address,
3096 noside);
3098 if (retval == NULL)
3099 error (_("No symbol \"%s\" in namespace \"%s\"."),
3100 name, TYPE_TAG_NAME (curtype));
3102 return retval;
3105 /* A helper function used by value_namespace_elt and
3106 value_struct_elt_for_reference. It looks up NAME inside the
3107 context CURTYPE; this works if CURTYPE is a namespace or if CURTYPE
3108 is a class and NAME refers to a type in CURTYPE itself (as opposed
3109 to, say, some base class of CURTYPE). */
3111 static struct value *
3112 value_maybe_namespace_elt (const struct type *curtype,
3113 char *name, int want_address,
3114 enum noside noside)
3116 const char *namespace_name = TYPE_TAG_NAME (curtype);
3117 struct symbol *sym;
3118 struct value *result;
3120 sym = cp_lookup_symbol_namespace (namespace_name, name, NULL,
3121 get_selected_block (0),
3122 VAR_DOMAIN, 1);
3124 if (sym == NULL)
3125 return NULL;
3126 else if ((noside == EVAL_AVOID_SIDE_EFFECTS)
3127 && (SYMBOL_CLASS (sym) == LOC_TYPEDEF))
3128 result = allocate_value (SYMBOL_TYPE (sym));
3129 else
3130 result = value_of_variable (sym, get_selected_block (0));
3132 if (result && want_address)
3133 result = value_addr (result);
3135 return result;
3138 /* Given a pointer value V, find the real (RTTI) type of the object it
3139 points to.
3141 Other parameters FULL, TOP, USING_ENC as with value_rtti_type()
3142 and refer to the values computed for the object pointed to. */
3144 struct type *
3145 value_rtti_target_type (struct value *v, int *full,
3146 int *top, int *using_enc)
3148 struct value *target;
3150 target = value_ind (v);
3152 return value_rtti_type (target, full, top, using_enc);
3155 /* Given a value pointed to by ARGP, check its real run-time type, and
3156 if that is different from the enclosing type, create a new value
3157 using the real run-time type as the enclosing type (and of the same
3158 type as ARGP) and return it, with the embedded offset adjusted to
3159 be the correct offset to the enclosed object. RTYPE is the type,
3160 and XFULL, XTOP, and XUSING_ENC are the other parameters, computed
3161 by value_rtti_type(). If these are available, they can be supplied
3162 and a second call to value_rtti_type() is avoided. (Pass RTYPE ==
3163 NULL if they're not available. */
3165 struct value *
3166 value_full_object (struct value *argp,
3167 struct type *rtype,
3168 int xfull, int xtop,
3169 int xusing_enc)
3171 struct type *real_type;
3172 int full = 0;
3173 int top = -1;
3174 int using_enc = 0;
3175 struct value *new_val;
3177 if (rtype)
3179 real_type = rtype;
3180 full = xfull;
3181 top = xtop;
3182 using_enc = xusing_enc;
3184 else
3185 real_type = value_rtti_type (argp, &full, &top, &using_enc);
3187 /* If no RTTI data, or if object is already complete, do nothing. */
3188 if (!real_type || real_type == value_enclosing_type (argp))
3189 return argp;
3191 /* If we have the full object, but for some reason the enclosing
3192 type is wrong, set it. */
3193 /* pai: FIXME -- sounds iffy */
3194 if (full)
3196 argp = value_change_enclosing_type (argp, real_type);
3197 return argp;
3200 /* Check if object is in memory */
3201 if (VALUE_LVAL (argp) != lval_memory)
3203 warning (_("Couldn't retrieve complete object of RTTI type %s; object may be in register(s)."),
3204 TYPE_NAME (real_type));
3206 return argp;
3209 /* All other cases -- retrieve the complete object. */
3210 /* Go back by the computed top_offset from the beginning of the
3211 object, adjusting for the embedded offset of argp if that's what
3212 value_rtti_type used for its computation. */
3213 new_val = value_at_lazy (real_type, value_address (argp) - top +
3214 (using_enc ? 0 : value_embedded_offset (argp)));
3215 deprecated_set_value_type (new_val, value_type (argp));
3216 set_value_embedded_offset (new_val, (using_enc
3217 ? top + value_embedded_offset (argp)
3218 : top));
3219 return new_val;
3223 /* Return the value of the local variable, if one exists.
3224 Flag COMPLAIN signals an error if the request is made in an
3225 inappropriate context. */
3227 struct value *
3228 value_of_local (const char *name, int complain)
3230 struct symbol *func, *sym;
3231 struct block *b;
3232 struct value * ret;
3233 struct frame_info *frame;
3235 if (complain)
3236 frame = get_selected_frame (_("no frame selected"));
3237 else
3239 frame = deprecated_safe_get_selected_frame ();
3240 if (frame == 0)
3241 return 0;
3244 func = get_frame_function (frame);
3245 if (!func)
3247 if (complain)
3248 error (_("no `%s' in nameless context"), name);
3249 else
3250 return 0;
3253 b = SYMBOL_BLOCK_VALUE (func);
3254 if (dict_empty (BLOCK_DICT (b)))
3256 if (complain)
3257 error (_("no args, no `%s'"), name);
3258 else
3259 return 0;
3262 /* Calling lookup_block_symbol is necessary to get the LOC_REGISTER
3263 symbol instead of the LOC_ARG one (if both exist). */
3264 sym = lookup_block_symbol (b, name, NULL, VAR_DOMAIN);
3265 if (sym == NULL)
3267 if (complain)
3268 error (_("current stack frame does not contain a variable named `%s'"),
3269 name);
3270 else
3271 return NULL;
3274 ret = read_var_value (sym, frame);
3275 if (ret == 0 && complain)
3276 error (_("`%s' argument unreadable"), name);
3277 return ret;
3280 /* C++/Objective-C: return the value of the class instance variable,
3281 if one exists. Flag COMPLAIN signals an error if the request is
3282 made in an inappropriate context. */
3284 struct value *
3285 value_of_this (int complain)
3287 if (!current_language->la_name_of_this)
3288 return 0;
3289 return value_of_local (current_language->la_name_of_this, complain);
3292 /* Create a slice (sub-string, sub-array) of ARRAY, that is LENGTH
3293 elements long, starting at LOWBOUND. The result has the same lower
3294 bound as the original ARRAY. */
3296 struct value *
3297 value_slice (struct value *array, int lowbound, int length)
3299 struct type *slice_range_type, *slice_type, *range_type;
3300 LONGEST lowerbound, upperbound;
3301 struct value *slice;
3302 struct type *array_type;
3304 array_type = check_typedef (value_type (array));
3305 if (TYPE_CODE (array_type) != TYPE_CODE_ARRAY
3306 && TYPE_CODE (array_type) != TYPE_CODE_STRING
3307 && TYPE_CODE (array_type) != TYPE_CODE_BITSTRING)
3308 error (_("cannot take slice of non-array"));
3310 range_type = TYPE_INDEX_TYPE (array_type);
3311 if (get_discrete_bounds (range_type, &lowerbound, &upperbound) < 0)
3312 error (_("slice from bad array or bitstring"));
3314 if (lowbound < lowerbound || length < 0
3315 || lowbound + length - 1 > upperbound)
3316 error (_("slice out of range"));
3318 /* FIXME-type-allocation: need a way to free this type when we are
3319 done with it. */
3320 slice_range_type = create_range_type ((struct type *) NULL,
3321 TYPE_TARGET_TYPE (range_type),
3322 lowbound,
3323 lowbound + length - 1);
3324 if (TYPE_CODE (array_type) == TYPE_CODE_BITSTRING)
3326 int i;
3328 slice_type = create_set_type ((struct type *) NULL,
3329 slice_range_type);
3330 TYPE_CODE (slice_type) = TYPE_CODE_BITSTRING;
3331 slice = value_zero (slice_type, not_lval);
3333 for (i = 0; i < length; i++)
3335 int element = value_bit_index (array_type,
3336 value_contents (array),
3337 lowbound + i);
3338 if (element < 0)
3339 error (_("internal error accessing bitstring"));
3340 else if (element > 0)
3342 int j = i % TARGET_CHAR_BIT;
3343 if (gdbarch_bits_big_endian (get_type_arch (array_type)))
3344 j = TARGET_CHAR_BIT - 1 - j;
3345 value_contents_raw (slice)[i / TARGET_CHAR_BIT] |= (1 << j);
3348 /* We should set the address, bitssize, and bitspos, so the
3349 slice can be used on the LHS, but that may require extensions
3350 to value_assign. For now, just leave as a non_lval.
3351 FIXME. */
3353 else
3355 struct type *element_type = TYPE_TARGET_TYPE (array_type);
3356 LONGEST offset =
3357 (lowbound - lowerbound) * TYPE_LENGTH (check_typedef (element_type));
3359 slice_type = create_array_type ((struct type *) NULL,
3360 element_type,
3361 slice_range_type);
3362 TYPE_CODE (slice_type) = TYPE_CODE (array_type);
3364 if (VALUE_LVAL (array) == lval_memory && value_lazy (array))
3365 slice = allocate_value_lazy (slice_type);
3366 else
3368 slice = allocate_value (slice_type);
3369 memcpy (value_contents_writeable (slice),
3370 value_contents (array) + offset,
3371 TYPE_LENGTH (slice_type));
3374 set_value_component_location (slice, array);
3375 VALUE_FRAME_ID (slice) = VALUE_FRAME_ID (array);
3376 set_value_offset (slice, value_offset (array) + offset);
3378 return slice;
3381 /* Create a value for a FORTRAN complex number. Currently most of the
3382 time values are coerced to COMPLEX*16 (i.e. a complex number
3383 composed of 2 doubles. This really should be a smarter routine
3384 that figures out precision inteligently as opposed to assuming
3385 doubles. FIXME: fmb */
3387 struct value *
3388 value_literal_complex (struct value *arg1,
3389 struct value *arg2,
3390 struct type *type)
3392 struct value *val;
3393 struct type *real_type = TYPE_TARGET_TYPE (type);
3395 val = allocate_value (type);
3396 arg1 = value_cast (real_type, arg1);
3397 arg2 = value_cast (real_type, arg2);
3399 memcpy (value_contents_raw (val),
3400 value_contents (arg1), TYPE_LENGTH (real_type));
3401 memcpy (value_contents_raw (val) + TYPE_LENGTH (real_type),
3402 value_contents (arg2), TYPE_LENGTH (real_type));
3403 return val;
3406 /* Cast a value into the appropriate complex data type. */
3408 static struct value *
3409 cast_into_complex (struct type *type, struct value *val)
3411 struct type *real_type = TYPE_TARGET_TYPE (type);
3413 if (TYPE_CODE (value_type (val)) == TYPE_CODE_COMPLEX)
3415 struct type *val_real_type = TYPE_TARGET_TYPE (value_type (val));
3416 struct value *re_val = allocate_value (val_real_type);
3417 struct value *im_val = allocate_value (val_real_type);
3419 memcpy (value_contents_raw (re_val),
3420 value_contents (val), TYPE_LENGTH (val_real_type));
3421 memcpy (value_contents_raw (im_val),
3422 value_contents (val) + TYPE_LENGTH (val_real_type),
3423 TYPE_LENGTH (val_real_type));
3425 return value_literal_complex (re_val, im_val, type);
3427 else if (TYPE_CODE (value_type (val)) == TYPE_CODE_FLT
3428 || TYPE_CODE (value_type (val)) == TYPE_CODE_INT)
3429 return value_literal_complex (val,
3430 value_zero (real_type, not_lval),
3431 type);
3432 else
3433 error (_("cannot cast non-number to complex"));
3436 void
3437 _initialize_valops (void)
3439 add_setshow_boolean_cmd ("overload-resolution", class_support,
3440 &overload_resolution, _("\
3441 Set overload resolution in evaluating C++ functions."), _("\
3442 Show overload resolution in evaluating C++ functions."),
3443 NULL, NULL,
3444 show_overload_resolution,
3445 &setlist, &showlist);
3446 overload_resolution = 1;