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