* spu-tdep.c: Update for unwinder changes.
[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 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
41 #include <errno.h>
42 #include "gdb_string.h"
43 #include "gdb_assert.h"
44 #include "cp-support.h"
45 #include "observer.h"
46
47 extern int overload_debug;
48 /* Local functions. */
49
50 static int typecmp (int staticp, int varargs, int nargs,
51 struct field t1[], struct value *t2[]);
52
53 static struct value *search_struct_field (char *, struct value *,
54 int, struct type *, int);
55
56 static struct value *search_struct_method (char *, struct value **,
57 struct value **,
58 int, int *, struct type *);
59
60 static int find_oload_champ_namespace (struct type **, int,
61 const char *, const char *,
62 struct symbol ***,
63 struct badness_vector **);
64
65 static
66 int find_oload_champ_namespace_loop (struct type **, int,
67 const char *, const char *,
68 int, struct symbol ***,
69 struct badness_vector **, int *);
70
71 static int find_oload_champ (struct type **, int, int, int,
72 struct fn_field *, struct symbol **,
73 struct badness_vector **);
74
75 static int oload_method_static (int, struct fn_field *, int);
76
77 enum oload_classification { STANDARD, NON_STANDARD, INCOMPATIBLE };
78
79 static enum
80 oload_classification classify_oload_match (struct badness_vector *,
81 int, int);
82
83 static struct value *value_struct_elt_for_reference (struct type *,
84 int, struct type *,
85 char *,
86 struct type *,
87 int, enum noside);
88
89 static struct value *value_namespace_elt (const struct type *,
90 char *, int , enum noside);
91
92 static struct value *value_maybe_namespace_elt (const struct type *,
93 char *, int,
94 enum noside);
95
96 static CORE_ADDR allocate_space_in_inferior (int);
97
98 static struct value *cast_into_complex (struct type *, struct value *);
99
100 static struct fn_field *find_method_list (struct value **, char *,
101 int, struct type *, int *,
102 struct type **, int *);
103
104 void _initialize_valops (void);
105
106 #if 0
107 /* Flag for whether we want to abandon failed expression evals by
108 default. */
109
110 static int auto_abandon = 0;
111 #endif
112
113 int overload_resolution = 0;
114 static void
115 show_overload_resolution (struct ui_file *file, int from_tty,
116 struct cmd_list_element *c,
117 const char *value)
118 {
119 fprintf_filtered (file, _("\
120 Overload resolution in evaluating C++ functions is %s.\n"),
121 value);
122 }
123
124 /* Find the address of function name NAME in the inferior. */
125
126 struct value *
127 find_function_in_inferior (const char *name)
128 {
129 struct symbol *sym;
130 sym = lookup_symbol (name, 0, VAR_DOMAIN, 0, NULL);
131 if (sym != NULL)
132 {
133 if (SYMBOL_CLASS (sym) != LOC_BLOCK)
134 {
135 error (_("\"%s\" exists in this program but is not a function."),
136 name);
137 }
138 return value_of_variable (sym, NULL);
139 }
140 else
141 {
142 struct minimal_symbol *msymbol =
143 lookup_minimal_symbol (name, NULL, NULL);
144 if (msymbol != NULL)
145 {
146 struct type *type;
147 CORE_ADDR maddr;
148 type = lookup_pointer_type (builtin_type_char);
149 type = lookup_function_type (type);
150 type = lookup_pointer_type (type);
151 maddr = SYMBOL_VALUE_ADDRESS (msymbol);
152 return value_from_pointer (type, maddr);
153 }
154 else
155 {
156 if (!target_has_execution)
157 error (_("evaluation of this expression requires the target program to be active"));
158 else
159 error (_("evaluation of this expression requires the program to have a function \"%s\"."), name);
160 }
161 }
162 }
163
164 /* Allocate NBYTES of space in the inferior using the inferior's
165 malloc and return a value that is a pointer to the allocated
166 space. */
167
168 struct value *
169 value_allocate_space_in_inferior (int len)
170 {
171 struct value *blocklen;
172 struct value *val =
173 find_function_in_inferior (gdbarch_name_of_malloc (current_gdbarch));
174
175 blocklen = value_from_longest (builtin_type_int, (LONGEST) len);
176 val = call_function_by_hand (val, 1, &blocklen);
177 if (value_logical_not (val))
178 {
179 if (!target_has_execution)
180 error (_("No memory available to program now: you need to start the target first"));
181 else
182 error (_("No memory available to program: call to malloc failed"));
183 }
184 return val;
185 }
186
187 static CORE_ADDR
188 allocate_space_in_inferior (int len)
189 {
190 return value_as_long (value_allocate_space_in_inferior (len));
191 }
192
193 /* Cast struct value VAL to type TYPE and return as a value.
194 Both type and val must be of TYPE_CODE_STRUCT or TYPE_CODE_UNION
195 for this to work. Typedef to one of the codes is permitted. */
196
197 static struct value *
198 value_cast_structs (struct type *type, struct value *v2)
199 {
200 struct type *t1;
201 struct type *t2;
202 struct value *v;
203
204 gdb_assert (type != NULL && v2 != NULL);
205
206 t1 = check_typedef (type);
207 t2 = check_typedef (value_type (v2));
208
209 /* Check preconditions. */
210 gdb_assert ((TYPE_CODE (t1) == TYPE_CODE_STRUCT
211 || TYPE_CODE (t1) == TYPE_CODE_UNION)
212 && !!"Precondition is that type is of STRUCT or UNION kind.");
213 gdb_assert ((TYPE_CODE (t2) == TYPE_CODE_STRUCT
214 || TYPE_CODE (t2) == TYPE_CODE_UNION)
215 && !!"Precondition is that value is of STRUCT or UNION kind");
216
217 /* Upcasting: look in the type of the source to see if it contains the
218 type of the target as a superclass. If so, we'll need to
219 offset the pointer rather than just change its type. */
220 if (TYPE_NAME (t1) != NULL)
221 {
222 v = search_struct_field (type_name_no_tag (t1),
223 v2, 0, t2, 1);
224 if (v)
225 return v;
226 }
227
228 /* Downcasting: look in the type of the target to see if it contains the
229 type of the source as a superclass. If so, we'll need to
230 offset the pointer rather than just change its type.
231 FIXME: This fails silently with virtual inheritance. */
232 if (TYPE_NAME (t2) != NULL)
233 {
234 v = search_struct_field (type_name_no_tag (t2),
235 value_zero (t1, not_lval), 0, t1, 1);
236 if (v)
237 {
238 /* Downcasting is possible (t1 is superclass of v2). */
239 CORE_ADDR addr2 = VALUE_ADDRESS (v2);
240 addr2 -= (VALUE_ADDRESS (v)
241 + value_offset (v)
242 + value_embedded_offset (v));
243 return value_at (type, addr2);
244 }
245 }
246 return v2;
247 }
248
249 /* Cast one pointer or reference type to another. Both TYPE and
250 the type of ARG2 should be pointer types, or else both should be
251 reference types. Returns the new pointer or reference. */
252
253 struct value *
254 value_cast_pointers (struct type *type, struct value *arg2)
255 {
256 struct type *type1 = check_typedef (type);
257 struct type *type2 = check_typedef (value_type (arg2));
258 struct type *t1 = check_typedef (TYPE_TARGET_TYPE (type));
259 struct type *t2 = check_typedef (TYPE_TARGET_TYPE (type2));
260
261 if (TYPE_CODE (t1) == TYPE_CODE_STRUCT
262 && TYPE_CODE (t2) == TYPE_CODE_STRUCT
263 && !value_logical_not (arg2))
264 {
265 struct value *v2;
266
267 if (TYPE_CODE (type2) == TYPE_CODE_REF)
268 v2 = coerce_ref (arg2);
269 else
270 v2 = value_ind (arg2);
271 gdb_assert (TYPE_CODE (value_type (v2)) == TYPE_CODE_STRUCT
272 && !!"Why did coercion fail?");
273 v2 = value_cast_structs (t1, v2);
274 /* At this point we have what we can have, un-dereference if needed. */
275 if (v2)
276 {
277 struct value *v = value_addr (v2);
278 deprecated_set_value_type (v, type);
279 return v;
280 }
281 }
282
283 /* No superclass found, just change the pointer type. */
284 arg2 = value_copy (arg2);
285 deprecated_set_value_type (arg2, type);
286 arg2 = value_change_enclosing_type (arg2, type);
287 set_value_pointed_to_offset (arg2, 0); /* pai: chk_val */
288 return arg2;
289 }
290
291 /* Cast value ARG2 to type TYPE and return as a value.
292 More general than a C cast: accepts any two types of the same length,
293 and if ARG2 is an lvalue it can be cast into anything at all. */
294 /* In C++, casts may change pointer or object representations. */
295
296 struct value *
297 value_cast (struct type *type, struct value *arg2)
298 {
299 enum type_code code1;
300 enum type_code code2;
301 int scalar;
302 struct type *type2;
303
304 int convert_to_boolean = 0;
305
306 if (value_type (arg2) == type)
307 return arg2;
308
309 code1 = TYPE_CODE (check_typedef (type));
310
311 /* Check if we are casting struct reference to struct reference. */
312 if (code1 == TYPE_CODE_REF)
313 {
314 /* We dereference type; then we recurse and finally
315 we generate value of the given reference. Nothing wrong with
316 that. */
317 struct type *t1 = check_typedef (type);
318 struct type *dereftype = check_typedef (TYPE_TARGET_TYPE (t1));
319 struct value *val = value_cast (dereftype, arg2);
320 return value_ref (val);
321 }
322
323 code2 = TYPE_CODE (check_typedef (value_type (arg2)));
324
325 if (code2 == TYPE_CODE_REF)
326 /* We deref the value and then do the cast. */
327 return value_cast (type, coerce_ref (arg2));
328
329 CHECK_TYPEDEF (type);
330 code1 = TYPE_CODE (type);
331 arg2 = coerce_ref (arg2);
332 type2 = check_typedef (value_type (arg2));
333
334 /* You can't cast to a reference type. See value_cast_pointers
335 instead. */
336 gdb_assert (code1 != TYPE_CODE_REF);
337
338 /* A cast to an undetermined-length array_type, such as
339 (TYPE [])OBJECT, is treated like a cast to (TYPE [N])OBJECT,
340 where N is sizeof(OBJECT)/sizeof(TYPE). */
341 if (code1 == TYPE_CODE_ARRAY)
342 {
343 struct type *element_type = TYPE_TARGET_TYPE (type);
344 unsigned element_length = TYPE_LENGTH (check_typedef (element_type));
345 if (element_length > 0
346 && TYPE_ARRAY_UPPER_BOUND_TYPE (type) == BOUND_CANNOT_BE_DETERMINED)
347 {
348 struct type *range_type = TYPE_INDEX_TYPE (type);
349 int val_length = TYPE_LENGTH (type2);
350 LONGEST low_bound, high_bound, new_length;
351 if (get_discrete_bounds (range_type, &low_bound, &high_bound) < 0)
352 low_bound = 0, high_bound = 0;
353 new_length = val_length / element_length;
354 if (val_length % element_length != 0)
355 warning (_("array element type size does not divide object size in cast"));
356 /* FIXME-type-allocation: need a way to free this type when
357 we are done with it. */
358 range_type = create_range_type ((struct type *) NULL,
359 TYPE_TARGET_TYPE (range_type),
360 low_bound,
361 new_length + low_bound - 1);
362 deprecated_set_value_type (arg2,
363 create_array_type ((struct type *) NULL,
364 element_type,
365 range_type));
366 return arg2;
367 }
368 }
369
370 if (current_language->c_style_arrays
371 && TYPE_CODE (type2) == TYPE_CODE_ARRAY)
372 arg2 = value_coerce_array (arg2);
373
374 if (TYPE_CODE (type2) == TYPE_CODE_FUNC)
375 arg2 = value_coerce_function (arg2);
376
377 type2 = check_typedef (value_type (arg2));
378 code2 = TYPE_CODE (type2);
379
380 if (code1 == TYPE_CODE_COMPLEX)
381 return cast_into_complex (type, arg2);
382 if (code1 == TYPE_CODE_BOOL)
383 {
384 code1 = TYPE_CODE_INT;
385 convert_to_boolean = 1;
386 }
387 if (code1 == TYPE_CODE_CHAR)
388 code1 = TYPE_CODE_INT;
389 if (code2 == TYPE_CODE_BOOL || code2 == TYPE_CODE_CHAR)
390 code2 = TYPE_CODE_INT;
391
392 scalar = (code2 == TYPE_CODE_INT || code2 == TYPE_CODE_FLT
393 || code2 == TYPE_CODE_DECFLOAT || code2 == TYPE_CODE_ENUM
394 || code2 == TYPE_CODE_RANGE);
395
396 if ((code1 == TYPE_CODE_STRUCT || code1 == TYPE_CODE_UNION)
397 && (code2 == TYPE_CODE_STRUCT || code2 == TYPE_CODE_UNION)
398 && TYPE_NAME (type) != 0)
399 return value_cast_structs (type, arg2);
400 if (code1 == TYPE_CODE_FLT && scalar)
401 return value_from_double (type, value_as_double (arg2));
402 else if (code1 == TYPE_CODE_DECFLOAT && scalar)
403 {
404 int dec_len = TYPE_LENGTH (type);
405 gdb_byte dec[16];
406
407 if (code2 == TYPE_CODE_FLT)
408 decimal_from_floating (arg2, dec, dec_len);
409 else if (code2 == TYPE_CODE_DECFLOAT)
410 decimal_convert (value_contents (arg2), TYPE_LENGTH (type2),
411 dec, dec_len);
412 else
413 /* The only option left is an integral type. */
414 decimal_from_integral (arg2, dec, dec_len);
415
416 return value_from_decfloat (type, dec);
417 }
418 else if ((code1 == TYPE_CODE_INT || code1 == TYPE_CODE_ENUM
419 || code1 == TYPE_CODE_RANGE)
420 && (scalar || code2 == TYPE_CODE_PTR
421 || code2 == TYPE_CODE_MEMBERPTR))
422 {
423 LONGEST longest;
424
425 /* When we cast pointers to integers, we mustn't use
426 gdbarch_pointer_to_address to find the address the pointer
427 represents, as value_as_long would. GDB should evaluate
428 expressions just as the compiler would --- and the compiler
429 sees a cast as a simple reinterpretation of the pointer's
430 bits. */
431 if (code2 == TYPE_CODE_PTR)
432 longest = extract_unsigned_integer (value_contents (arg2),
433 TYPE_LENGTH (type2));
434 else
435 longest = value_as_long (arg2);
436 return value_from_longest (type, convert_to_boolean ?
437 (LONGEST) (longest ? 1 : 0) : longest);
438 }
439 else if (code1 == TYPE_CODE_PTR && (code2 == TYPE_CODE_INT
440 || code2 == TYPE_CODE_ENUM
441 || code2 == TYPE_CODE_RANGE))
442 {
443 /* TYPE_LENGTH (type) is the length of a pointer, but we really
444 want the length of an address! -- we are really dealing with
445 addresses (i.e., gdb representations) not pointers (i.e.,
446 target representations) here.
447
448 This allows things like "print *(int *)0x01000234" to work
449 without printing a misleading message -- which would
450 otherwise occur when dealing with a target having two byte
451 pointers and four byte addresses. */
452
453 int addr_bit = gdbarch_addr_bit (current_gdbarch);
454
455 LONGEST longest = value_as_long (arg2);
456 if (addr_bit < sizeof (LONGEST) * HOST_CHAR_BIT)
457 {
458 if (longest >= ((LONGEST) 1 << addr_bit)
459 || longest <= -((LONGEST) 1 << addr_bit))
460 warning (_("value truncated"));
461 }
462 return value_from_longest (type, longest);
463 }
464 else if (code1 == TYPE_CODE_METHODPTR && code2 == TYPE_CODE_INT
465 && value_as_long (arg2) == 0)
466 {
467 struct value *result = allocate_value (type);
468 cplus_make_method_ptr (value_contents_writeable (result), 0, 0);
469 return result;
470 }
471 else if (code1 == TYPE_CODE_MEMBERPTR && code2 == TYPE_CODE_INT
472 && value_as_long (arg2) == 0)
473 {
474 /* The Itanium C++ ABI represents NULL pointers to members as
475 minus one, instead of biasing the normal case. */
476 return value_from_longest (type, -1);
477 }
478 else if (TYPE_LENGTH (type) == TYPE_LENGTH (type2))
479 {
480 if (code1 == TYPE_CODE_PTR && code2 == TYPE_CODE_PTR)
481 return value_cast_pointers (type, arg2);
482
483 arg2 = value_copy (arg2);
484 deprecated_set_value_type (arg2, type);
485 arg2 = value_change_enclosing_type (arg2, type);
486 set_value_pointed_to_offset (arg2, 0); /* pai: chk_val */
487 return arg2;
488 }
489 else if (VALUE_LVAL (arg2) == lval_memory)
490 return value_at_lazy (type,
491 VALUE_ADDRESS (arg2) + value_offset (arg2));
492 else if (code1 == TYPE_CODE_VOID)
493 {
494 return value_zero (builtin_type_void, not_lval);
495 }
496 else
497 {
498 error (_("Invalid cast."));
499 return 0;
500 }
501 }
502
503 /* Create a value of type TYPE that is zero, and return it. */
504
505 struct value *
506 value_zero (struct type *type, enum lval_type lv)
507 {
508 struct value *val = allocate_value (type);
509 VALUE_LVAL (val) = lv;
510
511 return val;
512 }
513
514 /* Create a value of numeric type TYPE that is one, and return it. */
515
516 struct value *
517 value_one (struct type *type, enum lval_type lv)
518 {
519 struct type *type1 = check_typedef (type);
520 struct value *val = NULL; /* avoid -Wall warning */
521
522 if (TYPE_CODE (type1) == TYPE_CODE_DECFLOAT)
523 {
524 struct value *int_one = value_from_longest (builtin_type_int, 1);
525 struct value *val;
526 gdb_byte v[16];
527
528 decimal_from_integral (int_one, v, TYPE_LENGTH (builtin_type_int));
529 val = value_from_decfloat (type, v);
530 }
531 else if (TYPE_CODE (type1) == TYPE_CODE_FLT)
532 {
533 val = value_from_double (type, (DOUBLEST) 1);
534 }
535 else if (is_integral_type (type1))
536 {
537 val = value_from_longest (type, (LONGEST) 1);
538 }
539 else
540 {
541 error (_("Not a numeric type."));
542 }
543
544 VALUE_LVAL (val) = lv;
545 return val;
546 }
547
548 /* Return a value with type TYPE located at ADDR.
549
550 Call value_at only if the data needs to be fetched immediately;
551 if we can be 'lazy' and defer the fetch, perhaps indefinately, call
552 value_at_lazy instead. value_at_lazy simply records the address of
553 the data and sets the lazy-evaluation-required flag. The lazy flag
554 is tested in the value_contents macro, which is used if and when
555 the contents are actually required.
556
557 Note: value_at does *NOT* handle embedded offsets; perform such
558 adjustments before or after calling it. */
559
560 struct value *
561 value_at (struct type *type, CORE_ADDR addr)
562 {
563 struct value *val;
564
565 if (TYPE_CODE (check_typedef (type)) == TYPE_CODE_VOID)
566 error (_("Attempt to dereference a generic pointer."));
567
568 val = allocate_value (type);
569
570 read_memory (addr, value_contents_all_raw (val), TYPE_LENGTH (type));
571
572 VALUE_LVAL (val) = lval_memory;
573 VALUE_ADDRESS (val) = addr;
574
575 return val;
576 }
577
578 /* Return a lazy value with type TYPE located at ADDR (cf. value_at). */
579
580 struct value *
581 value_at_lazy (struct type *type, CORE_ADDR addr)
582 {
583 struct value *val;
584
585 if (TYPE_CODE (check_typedef (type)) == TYPE_CODE_VOID)
586 error (_("Attempt to dereference a generic pointer."));
587
588 val = allocate_value (type);
589
590 VALUE_LVAL (val) = lval_memory;
591 VALUE_ADDRESS (val) = addr;
592 set_value_lazy (val, 1);
593
594 return val;
595 }
596
597 /* Called only from the value_contents and value_contents_all()
598 macros, if the current data for a variable needs to be loaded into
599 value_contents(VAL). Fetches the data from the user's process, and
600 clears the lazy flag to indicate that the data in the buffer is
601 valid.
602
603 If the value is zero-length, we avoid calling read_memory, which
604 would abort. We mark the value as fetched anyway -- all 0 bytes of
605 it.
606
607 This function returns a value because it is used in the
608 value_contents macro as part of an expression, where a void would
609 not work. The value is ignored. */
610
611 int
612 value_fetch_lazy (struct value *val)
613 {
614 if (VALUE_LVAL (val) == lval_memory)
615 {
616 CORE_ADDR addr = VALUE_ADDRESS (val) + value_offset (val);
617 int length = TYPE_LENGTH (value_enclosing_type (val));
618
619 struct type *type = value_type (val);
620 if (length)
621 read_memory (addr, value_contents_all_raw (val), length);
622 }
623 else if (VALUE_LVAL (val) == lval_register)
624 {
625 struct frame_info *frame;
626 int regnum;
627 struct type *type = check_typedef (value_type (val));
628 struct value *new_val = val, *mark = value_mark ();
629
630 /* Offsets are not supported here; lazy register values must
631 refer to the entire register. */
632 gdb_assert (value_offset (val) == 0);
633
634 while (VALUE_LVAL (new_val) == lval_register && value_lazy (new_val))
635 {
636 frame = frame_find_by_id (VALUE_FRAME_ID (new_val));
637 regnum = VALUE_REGNUM (new_val);
638
639 gdb_assert (frame != NULL);
640
641 /* Convertible register routines are used for multi-register
642 values and for interpretation in different types
643 (e.g. float or int from a double register). Lazy
644 register values should have the register's natural type,
645 so they do not apply. */
646 gdb_assert (!gdbarch_convert_register_p (get_frame_arch (frame),
647 regnum, type));
648
649 new_val = get_frame_register_value (frame, regnum);
650 }
651
652 /* If it's still lazy (for instance, a saved register on the
653 stack), fetch it. */
654 if (value_lazy (new_val))
655 value_fetch_lazy (new_val);
656
657 /* If the register was not saved, mark it unavailable. */
658 if (value_optimized_out (new_val))
659 set_value_optimized_out (val, 1);
660 else
661 memcpy (value_contents_raw (val), value_contents (new_val),
662 TYPE_LENGTH (type));
663
664 if (frame_debug)
665 {
666 frame = frame_find_by_id (VALUE_FRAME_ID (val));
667 regnum = VALUE_REGNUM (val);
668
669 fprintf_unfiltered (gdb_stdlog, "\
670 { value_fetch_lazy (frame=%d,regnum=%d(%s),...) ",
671 frame_relative_level (frame), regnum,
672 frame_map_regnum_to_name (frame, regnum));
673
674 fprintf_unfiltered (gdb_stdlog, "->");
675 if (value_optimized_out (new_val))
676 fprintf_unfiltered (gdb_stdlog, " optimized out");
677 else
678 {
679 int i;
680 const gdb_byte *buf = value_contents (new_val);
681
682 if (VALUE_LVAL (new_val) == lval_register)
683 fprintf_unfiltered (gdb_stdlog, " register=%d",
684 VALUE_REGNUM (new_val));
685 else if (VALUE_LVAL (new_val) == lval_memory)
686 fprintf_unfiltered (gdb_stdlog, " address=0x%s",
687 paddr_nz (VALUE_ADDRESS (new_val)));
688 else
689 fprintf_unfiltered (gdb_stdlog, " computed");
690
691 fprintf_unfiltered (gdb_stdlog, " bytes=");
692 fprintf_unfiltered (gdb_stdlog, "[");
693 for (i = 0;
694 i < register_size (get_frame_arch (frame), regnum);
695 i++)
696 fprintf_unfiltered (gdb_stdlog, "%02x", buf[i]);
697 fprintf_unfiltered (gdb_stdlog, "]");
698 }
699
700 fprintf_unfiltered (gdb_stdlog, " }\n");
701 }
702
703 /* Dispose of the intermediate values. This prevents
704 watchpoints from trying to watch the saved frame pointer. */
705 value_free_to_mark (mark);
706 }
707 else
708 internal_error (__FILE__, __LINE__, "Unexpected lazy value type.");
709
710 set_value_lazy (val, 0);
711 return 0;
712 }
713
714
715 /* Store the contents of FROMVAL into the location of TOVAL.
716 Return a new value with the location of TOVAL and contents of FROMVAL. */
717
718 struct value *
719 value_assign (struct value *toval, struct value *fromval)
720 {
721 struct type *type;
722 struct value *val;
723 struct frame_id old_frame;
724
725 if (!deprecated_value_modifiable (toval))
726 error (_("Left operand of assignment is not a modifiable lvalue."));
727
728 toval = coerce_ref (toval);
729
730 type = value_type (toval);
731 if (VALUE_LVAL (toval) != lval_internalvar)
732 {
733 toval = value_coerce_to_target (toval);
734 fromval = value_cast (type, fromval);
735 }
736 else
737 {
738 /* Coerce arrays and functions to pointers, except for arrays
739 which only live in GDB's storage. */
740 if (!value_must_coerce_to_target (fromval))
741 fromval = coerce_array (fromval);
742 }
743
744 CHECK_TYPEDEF (type);
745
746 /* Since modifying a register can trash the frame chain, and
747 modifying memory can trash the frame cache, we save the old frame
748 and then restore the new frame afterwards. */
749 old_frame = get_frame_id (deprecated_safe_get_selected_frame ());
750
751 switch (VALUE_LVAL (toval))
752 {
753 case lval_internalvar:
754 set_internalvar (VALUE_INTERNALVAR (toval), fromval);
755 val = value_copy (VALUE_INTERNALVAR (toval)->value);
756 val = value_change_enclosing_type (val,
757 value_enclosing_type (fromval));
758 set_value_embedded_offset (val, value_embedded_offset (fromval));
759 set_value_pointed_to_offset (val,
760 value_pointed_to_offset (fromval));
761 return val;
762
763 case lval_internalvar_component:
764 set_internalvar_component (VALUE_INTERNALVAR (toval),
765 value_offset (toval),
766 value_bitpos (toval),
767 value_bitsize (toval),
768 fromval);
769 break;
770
771 case lval_memory:
772 {
773 const gdb_byte *dest_buffer;
774 CORE_ADDR changed_addr;
775 int changed_len;
776 gdb_byte buffer[sizeof (LONGEST)];
777
778 if (value_bitsize (toval))
779 {
780 /* We assume that the argument to read_memory is in units
781 of host chars. FIXME: Is that correct? */
782 changed_len = (value_bitpos (toval)
783 + value_bitsize (toval)
784 + HOST_CHAR_BIT - 1)
785 / HOST_CHAR_BIT;
786
787 if (changed_len > (int) sizeof (LONGEST))
788 error (_("Can't handle bitfields which don't fit in a %d bit word."),
789 (int) sizeof (LONGEST) * HOST_CHAR_BIT);
790
791 read_memory (VALUE_ADDRESS (toval) + value_offset (toval),
792 buffer, changed_len);
793 modify_field (buffer, value_as_long (fromval),
794 value_bitpos (toval), value_bitsize (toval));
795 changed_addr = VALUE_ADDRESS (toval) + value_offset (toval);
796 dest_buffer = buffer;
797 }
798 else
799 {
800 changed_addr = VALUE_ADDRESS (toval) + value_offset (toval);
801 changed_len = TYPE_LENGTH (type);
802 dest_buffer = value_contents (fromval);
803 }
804
805 write_memory (changed_addr, dest_buffer, changed_len);
806 if (deprecated_memory_changed_hook)
807 deprecated_memory_changed_hook (changed_addr, changed_len);
808 }
809 break;
810
811 case lval_register:
812 {
813 struct frame_info *frame;
814 int value_reg;
815
816 /* Figure out which frame this is in currently. */
817 frame = frame_find_by_id (VALUE_FRAME_ID (toval));
818 value_reg = VALUE_REGNUM (toval);
819
820 if (!frame)
821 error (_("Value being assigned to is no longer active."));
822
823 if (gdbarch_convert_register_p
824 (current_gdbarch, VALUE_REGNUM (toval), type))
825 {
826 /* If TOVAL is a special machine register requiring
827 conversion of program values to a special raw
828 format. */
829 gdbarch_value_to_register (current_gdbarch, frame,
830 VALUE_REGNUM (toval), type,
831 value_contents (fromval));
832 }
833 else
834 {
835 if (value_bitsize (toval))
836 {
837 int changed_len;
838 gdb_byte buffer[sizeof (LONGEST)];
839
840 changed_len = (value_bitpos (toval)
841 + value_bitsize (toval)
842 + HOST_CHAR_BIT - 1)
843 / HOST_CHAR_BIT;
844
845 if (changed_len > (int) sizeof (LONGEST))
846 error (_("Can't handle bitfields which don't fit in a %d bit word."),
847 (int) sizeof (LONGEST) * HOST_CHAR_BIT);
848
849 get_frame_register_bytes (frame, value_reg,
850 value_offset (toval),
851 changed_len, buffer);
852
853 modify_field (buffer, value_as_long (fromval),
854 value_bitpos (toval),
855 value_bitsize (toval));
856
857 put_frame_register_bytes (frame, value_reg,
858 value_offset (toval),
859 changed_len, buffer);
860 }
861 else
862 {
863 put_frame_register_bytes (frame, value_reg,
864 value_offset (toval),
865 TYPE_LENGTH (type),
866 value_contents (fromval));
867 }
868 }
869
870 if (deprecated_register_changed_hook)
871 deprecated_register_changed_hook (-1);
872 observer_notify_target_changed (&current_target);
873 break;
874 }
875
876 default:
877 error (_("Left operand of assignment is not an lvalue."));
878 }
879
880 /* Assigning to the stack pointer, frame pointer, and other
881 (architecture and calling convention specific) registers may
882 cause the frame cache to be out of date. Assigning to memory
883 also can. We just do this on all assignments to registers or
884 memory, for simplicity's sake; I doubt the slowdown matters. */
885 switch (VALUE_LVAL (toval))
886 {
887 case lval_memory:
888 case lval_register:
889
890 reinit_frame_cache ();
891
892 /* Having destroyed the frame cache, restore the selected
893 frame. */
894
895 /* FIXME: cagney/2002-11-02: There has to be a better way of
896 doing this. Instead of constantly saving/restoring the
897 frame. Why not create a get_selected_frame() function that,
898 having saved the selected frame's ID can automatically
899 re-find the previously selected frame automatically. */
900
901 {
902 struct frame_info *fi = frame_find_by_id (old_frame);
903 if (fi != NULL)
904 select_frame (fi);
905 }
906
907 break;
908 default:
909 break;
910 }
911
912 /* If the field does not entirely fill a LONGEST, then zero the sign
913 bits. If the field is signed, and is negative, then sign
914 extend. */
915 if ((value_bitsize (toval) > 0)
916 && (value_bitsize (toval) < 8 * (int) sizeof (LONGEST)))
917 {
918 LONGEST fieldval = value_as_long (fromval);
919 LONGEST valmask = (((ULONGEST) 1) << value_bitsize (toval)) - 1;
920
921 fieldval &= valmask;
922 if (!TYPE_UNSIGNED (type)
923 && (fieldval & (valmask ^ (valmask >> 1))))
924 fieldval |= ~valmask;
925
926 fromval = value_from_longest (type, fieldval);
927 }
928
929 val = value_copy (toval);
930 memcpy (value_contents_raw (val), value_contents (fromval),
931 TYPE_LENGTH (type));
932 deprecated_set_value_type (val, type);
933 val = value_change_enclosing_type (val,
934 value_enclosing_type (fromval));
935 set_value_embedded_offset (val, value_embedded_offset (fromval));
936 set_value_pointed_to_offset (val, value_pointed_to_offset (fromval));
937
938 return val;
939 }
940
941 /* Extend a value VAL to COUNT repetitions of its type. */
942
943 struct value *
944 value_repeat (struct value *arg1, int count)
945 {
946 struct value *val;
947
948 if (VALUE_LVAL (arg1) != lval_memory)
949 error (_("Only values in memory can be extended with '@'."));
950 if (count < 1)
951 error (_("Invalid number %d of repetitions."), count);
952
953 val = allocate_repeat_value (value_enclosing_type (arg1), count);
954
955 read_memory (VALUE_ADDRESS (arg1) + value_offset (arg1),
956 value_contents_all_raw (val),
957 TYPE_LENGTH (value_enclosing_type (val)));
958 VALUE_LVAL (val) = lval_memory;
959 VALUE_ADDRESS (val) = VALUE_ADDRESS (arg1) + value_offset (arg1);
960
961 return val;
962 }
963
964 struct value *
965 value_of_variable (struct symbol *var, struct block *b)
966 {
967 struct value *val;
968 struct frame_info *frame = NULL;
969
970 if (!b)
971 frame = NULL; /* Use selected frame. */
972 else if (symbol_read_needs_frame (var))
973 {
974 frame = block_innermost_frame (b);
975 if (!frame)
976 {
977 if (BLOCK_FUNCTION (b)
978 && SYMBOL_PRINT_NAME (BLOCK_FUNCTION (b)))
979 error (_("No frame is currently executing in block %s."),
980 SYMBOL_PRINT_NAME (BLOCK_FUNCTION (b)));
981 else
982 error (_("No frame is currently executing in specified block"));
983 }
984 }
985
986 val = read_var_value (var, frame);
987 if (!val)
988 error (_("Address of symbol \"%s\" is unknown."), SYMBOL_PRINT_NAME (var));
989
990 return val;
991 }
992
993 /* Return one if VAL does not live in target memory, but should in order
994 to operate on it. Otherwise return zero. */
995
996 int
997 value_must_coerce_to_target (struct value *val)
998 {
999 struct type *valtype;
1000
1001 /* The only lval kinds which do not live in target memory. */
1002 if (VALUE_LVAL (val) != not_lval
1003 && VALUE_LVAL (val) != lval_internalvar)
1004 return 0;
1005
1006 valtype = check_typedef (value_type (val));
1007
1008 switch (TYPE_CODE (valtype))
1009 {
1010 case TYPE_CODE_ARRAY:
1011 case TYPE_CODE_STRING:
1012 return 1;
1013 default:
1014 return 0;
1015 }
1016 }
1017
1018 /* Make sure that VAL lives in target memory if it's supposed to. For instance,
1019 strings are constructed as character arrays in GDB's storage, and this
1020 function copies them to the target. */
1021
1022 struct value *
1023 value_coerce_to_target (struct value *val)
1024 {
1025 LONGEST length;
1026 CORE_ADDR addr;
1027
1028 if (!value_must_coerce_to_target (val))
1029 return val;
1030
1031 length = TYPE_LENGTH (check_typedef (value_type (val)));
1032 addr = allocate_space_in_inferior (length);
1033 write_memory (addr, value_contents (val), length);
1034 return value_at_lazy (value_type (val), addr);
1035 }
1036
1037 /* Given a value which is an array, return a value which is a pointer
1038 to its first element, regardless of whether or not the array has a
1039 nonzero lower bound.
1040
1041 FIXME: A previous comment here indicated that this routine should
1042 be substracting the array's lower bound. It's not clear to me that
1043 this is correct. Given an array subscripting operation, it would
1044 certainly work to do the adjustment here, essentially computing:
1045
1046 (&array[0] - (lowerbound * sizeof array[0])) + (index * sizeof array[0])
1047
1048 However I believe a more appropriate and logical place to account
1049 for the lower bound is to do so in value_subscript, essentially
1050 computing:
1051
1052 (&array[0] + ((index - lowerbound) * sizeof array[0]))
1053
1054 As further evidence consider what would happen with operations
1055 other than array subscripting, where the caller would get back a
1056 value that had an address somewhere before the actual first element
1057 of the array, and the information about the lower bound would be
1058 lost because of the coercion to pointer type.
1059 */
1060
1061 struct value *
1062 value_coerce_array (struct value *arg1)
1063 {
1064 struct type *type = check_typedef (value_type (arg1));
1065
1066 /* If the user tries to do something requiring a pointer with an
1067 array that has not yet been pushed to the target, then this would
1068 be a good time to do so. */
1069 arg1 = value_coerce_to_target (arg1);
1070
1071 if (VALUE_LVAL (arg1) != lval_memory)
1072 error (_("Attempt to take address of value not located in memory."));
1073
1074 return value_from_pointer (lookup_pointer_type (TYPE_TARGET_TYPE (type)),
1075 (VALUE_ADDRESS (arg1) + value_offset (arg1)));
1076 }
1077
1078 /* Given a value which is a function, return a value which is a pointer
1079 to it. */
1080
1081 struct value *
1082 value_coerce_function (struct value *arg1)
1083 {
1084 struct value *retval;
1085
1086 if (VALUE_LVAL (arg1) != lval_memory)
1087 error (_("Attempt to take address of value not located in memory."));
1088
1089 retval = value_from_pointer (lookup_pointer_type (value_type (arg1)),
1090 (VALUE_ADDRESS (arg1) + value_offset (arg1)));
1091 return retval;
1092 }
1093
1094 /* Return a pointer value for the object for which ARG1 is the
1095 contents. */
1096
1097 struct value *
1098 value_addr (struct value *arg1)
1099 {
1100 struct value *arg2;
1101
1102 struct type *type = check_typedef (value_type (arg1));
1103 if (TYPE_CODE (type) == TYPE_CODE_REF)
1104 {
1105 /* Copy the value, but change the type from (T&) to (T*). We
1106 keep the same location information, which is efficient, and
1107 allows &(&X) to get the location containing the reference. */
1108 arg2 = value_copy (arg1);
1109 deprecated_set_value_type (arg2,
1110 lookup_pointer_type (TYPE_TARGET_TYPE (type)));
1111 return arg2;
1112 }
1113 if (TYPE_CODE (type) == TYPE_CODE_FUNC)
1114 return value_coerce_function (arg1);
1115
1116 /* If this is an array that has not yet been pushed to the target,
1117 then this would be a good time to force it to memory. */
1118 arg1 = value_coerce_to_target (arg1);
1119
1120 if (VALUE_LVAL (arg1) != lval_memory)
1121 error (_("Attempt to take address of value not located in memory."));
1122
1123 /* Get target memory address */
1124 arg2 = value_from_pointer (lookup_pointer_type (value_type (arg1)),
1125 (VALUE_ADDRESS (arg1)
1126 + value_offset (arg1)
1127 + value_embedded_offset (arg1)));
1128
1129 /* This may be a pointer to a base subobject; so remember the
1130 full derived object's type ... */
1131 arg2 = value_change_enclosing_type (arg2, lookup_pointer_type (value_enclosing_type (arg1)));
1132 /* ... and also the relative position of the subobject in the full
1133 object. */
1134 set_value_pointed_to_offset (arg2, value_embedded_offset (arg1));
1135 return arg2;
1136 }
1137
1138 /* Return a reference value for the object for which ARG1 is the
1139 contents. */
1140
1141 struct value *
1142 value_ref (struct value *arg1)
1143 {
1144 struct value *arg2;
1145
1146 struct type *type = check_typedef (value_type (arg1));
1147 if (TYPE_CODE (type) == TYPE_CODE_REF)
1148 return arg1;
1149
1150 arg2 = value_addr (arg1);
1151 deprecated_set_value_type (arg2, lookup_reference_type (type));
1152 return arg2;
1153 }
1154
1155 /* Given a value of a pointer type, apply the C unary * operator to
1156 it. */
1157
1158 struct value *
1159 value_ind (struct value *arg1)
1160 {
1161 struct type *base_type;
1162 struct value *arg2;
1163
1164 arg1 = coerce_array (arg1);
1165
1166 base_type = check_typedef (value_type (arg1));
1167
1168 /* Allow * on an integer so we can cast it to whatever we want.
1169 This returns an int, which seems like the most C-like thing to
1170 do. "long long" variables are rare enough that
1171 BUILTIN_TYPE_LONGEST would seem to be a mistake. */
1172 if (TYPE_CODE (base_type) == TYPE_CODE_INT)
1173 return value_at_lazy (builtin_type_int,
1174 (CORE_ADDR) value_as_address (arg1));
1175 else if (TYPE_CODE (base_type) == TYPE_CODE_PTR)
1176 {
1177 struct type *enc_type;
1178 /* We may be pointing to something embedded in a larger object.
1179 Get the real type of the enclosing object. */
1180 enc_type = check_typedef (value_enclosing_type (arg1));
1181 enc_type = TYPE_TARGET_TYPE (enc_type);
1182
1183 if (TYPE_CODE (check_typedef (enc_type)) == TYPE_CODE_FUNC
1184 || TYPE_CODE (check_typedef (enc_type)) == TYPE_CODE_METHOD)
1185 /* For functions, go through find_function_addr, which knows
1186 how to handle function descriptors. */
1187 arg2 = value_at_lazy (enc_type,
1188 find_function_addr (arg1, NULL));
1189 else
1190 /* Retrieve the enclosing object pointed to */
1191 arg2 = value_at_lazy (enc_type,
1192 (value_as_address (arg1)
1193 - value_pointed_to_offset (arg1)));
1194
1195 /* Re-adjust type. */
1196 deprecated_set_value_type (arg2, TYPE_TARGET_TYPE (base_type));
1197 /* Add embedding info. */
1198 arg2 = value_change_enclosing_type (arg2, enc_type);
1199 set_value_embedded_offset (arg2, value_pointed_to_offset (arg1));
1200
1201 /* We may be pointing to an object of some derived type. */
1202 arg2 = value_full_object (arg2, NULL, 0, 0, 0);
1203 return arg2;
1204 }
1205
1206 error (_("Attempt to take contents of a non-pointer value."));
1207 return 0; /* For lint -- never reached. */
1208 }
1209 \f
1210 /* Create a value for an array by allocating space in GDB, copying
1211 copying the data into that space, and then setting up an array
1212 value.
1213
1214 The array bounds are set from LOWBOUND and HIGHBOUND, and the array
1215 is populated from the values passed in ELEMVEC.
1216
1217 The element type of the array is inherited from the type of the
1218 first element, and all elements must have the same size (though we
1219 don't currently enforce any restriction on their types). */
1220
1221 struct value *
1222 value_array (int lowbound, int highbound, struct value **elemvec)
1223 {
1224 int nelem;
1225 int idx;
1226 unsigned int typelength;
1227 struct value *val;
1228 struct type *rangetype;
1229 struct type *arraytype;
1230 CORE_ADDR addr;
1231
1232 /* Validate that the bounds are reasonable and that each of the
1233 elements have the same size. */
1234
1235 nelem = highbound - lowbound + 1;
1236 if (nelem <= 0)
1237 {
1238 error (_("bad array bounds (%d, %d)"), lowbound, highbound);
1239 }
1240 typelength = TYPE_LENGTH (value_enclosing_type (elemvec[0]));
1241 for (idx = 1; idx < nelem; idx++)
1242 {
1243 if (TYPE_LENGTH (value_enclosing_type (elemvec[idx])) != typelength)
1244 {
1245 error (_("array elements must all be the same size"));
1246 }
1247 }
1248
1249 rangetype = create_range_type ((struct type *) NULL,
1250 builtin_type_int,
1251 lowbound, highbound);
1252 arraytype = create_array_type ((struct type *) NULL,
1253 value_enclosing_type (elemvec[0]),
1254 rangetype);
1255
1256 if (!current_language->c_style_arrays)
1257 {
1258 val = allocate_value (arraytype);
1259 for (idx = 0; idx < nelem; idx++)
1260 {
1261 memcpy (value_contents_all_raw (val) + (idx * typelength),
1262 value_contents_all (elemvec[idx]),
1263 typelength);
1264 }
1265 return val;
1266 }
1267
1268 /* Allocate space to store the array, and then initialize it by
1269 copying in each element. */
1270
1271 val = allocate_value (arraytype);
1272 for (idx = 0; idx < nelem; idx++)
1273 memcpy (value_contents_writeable (val) + (idx * typelength),
1274 value_contents_all (elemvec[idx]),
1275 typelength);
1276 return val;
1277 }
1278
1279 /* Create a value for a string constant by allocating space in the
1280 inferior, copying the data into that space, and returning the
1281 address with type TYPE_CODE_STRING. PTR points to the string
1282 constant data; LEN is number of characters.
1283
1284 Note that string types are like array of char types with a lower
1285 bound of zero and an upper bound of LEN - 1. Also note that the
1286 string may contain embedded null bytes. */
1287
1288 struct value *
1289 value_string (char *ptr, int len)
1290 {
1291 struct value *val;
1292 int lowbound = current_language->string_lower_bound;
1293 struct type *rangetype = create_range_type ((struct type *) NULL,
1294 builtin_type_int,
1295 lowbound,
1296 len + lowbound - 1);
1297 struct type *stringtype
1298 = create_string_type ((struct type *) NULL, rangetype);
1299 CORE_ADDR addr;
1300
1301 if (current_language->c_style_arrays == 0)
1302 {
1303 val = allocate_value (stringtype);
1304 memcpy (value_contents_raw (val), ptr, len);
1305 return val;
1306 }
1307
1308
1309 /* Allocate space to store the string in the inferior, and then copy
1310 LEN bytes from PTR in gdb to that address in the inferior. */
1311
1312 addr = allocate_space_in_inferior (len);
1313 write_memory (addr, (gdb_byte *) ptr, len);
1314
1315 val = value_at_lazy (stringtype, addr);
1316 return (val);
1317 }
1318
1319 struct value *
1320 value_bitstring (char *ptr, int len)
1321 {
1322 struct value *val;
1323 struct type *domain_type = create_range_type (NULL,
1324 builtin_type_int,
1325 0, len - 1);
1326 struct type *type = create_set_type ((struct type *) NULL,
1327 domain_type);
1328 TYPE_CODE (type) = TYPE_CODE_BITSTRING;
1329 val = allocate_value (type);
1330 memcpy (value_contents_raw (val), ptr, TYPE_LENGTH (type));
1331 return val;
1332 }
1333 \f
1334 /* See if we can pass arguments in T2 to a function which takes
1335 arguments of types T1. T1 is a list of NARGS arguments, and T2 is
1336 a NULL-terminated vector. If some arguments need coercion of some
1337 sort, then the coerced values are written into T2. Return value is
1338 0 if the arguments could be matched, or the position at which they
1339 differ if not.
1340
1341 STATICP is nonzero if the T1 argument list came from a static
1342 member function. T2 will still include the ``this'' pointer, but
1343 it will be skipped.
1344
1345 For non-static member functions, we ignore the first argument,
1346 which is the type of the instance variable. This is because we
1347 want to handle calls with objects from derived classes. This is
1348 not entirely correct: we should actually check to make sure that a
1349 requested operation is type secure, shouldn't we? FIXME. */
1350
1351 static int
1352 typecmp (int staticp, int varargs, int nargs,
1353 struct field t1[], struct value *t2[])
1354 {
1355 int i;
1356
1357 if (t2 == 0)
1358 internal_error (__FILE__, __LINE__,
1359 _("typecmp: no argument list"));
1360
1361 /* Skip ``this'' argument if applicable. T2 will always include
1362 THIS. */
1363 if (staticp)
1364 t2 ++;
1365
1366 for (i = 0;
1367 (i < nargs) && TYPE_CODE (t1[i].type) != TYPE_CODE_VOID;
1368 i++)
1369 {
1370 struct type *tt1, *tt2;
1371
1372 if (!t2[i])
1373 return i + 1;
1374
1375 tt1 = check_typedef (t1[i].type);
1376 tt2 = check_typedef (value_type (t2[i]));
1377
1378 if (TYPE_CODE (tt1) == TYPE_CODE_REF
1379 /* We should be doing hairy argument matching, as below. */
1380 && (TYPE_CODE (check_typedef (TYPE_TARGET_TYPE (tt1))) == TYPE_CODE (tt2)))
1381 {
1382 if (TYPE_CODE (tt2) == TYPE_CODE_ARRAY)
1383 t2[i] = value_coerce_array (t2[i]);
1384 else
1385 t2[i] = value_ref (t2[i]);
1386 continue;
1387 }
1388
1389 /* djb - 20000715 - Until the new type structure is in the
1390 place, and we can attempt things like implicit conversions,
1391 we need to do this so you can take something like a map<const
1392 char *>, and properly access map["hello"], because the
1393 argument to [] will be a reference to a pointer to a char,
1394 and the argument will be a pointer to a char. */
1395 while (TYPE_CODE(tt1) == TYPE_CODE_REF
1396 || TYPE_CODE (tt1) == TYPE_CODE_PTR)
1397 {
1398 tt1 = check_typedef( TYPE_TARGET_TYPE(tt1) );
1399 }
1400 while (TYPE_CODE(tt2) == TYPE_CODE_ARRAY
1401 || TYPE_CODE(tt2) == TYPE_CODE_PTR
1402 || TYPE_CODE(tt2) == TYPE_CODE_REF)
1403 {
1404 tt2 = check_typedef (TYPE_TARGET_TYPE(tt2));
1405 }
1406 if (TYPE_CODE (tt1) == TYPE_CODE (tt2))
1407 continue;
1408 /* Array to pointer is a `trivial conversion' according to the
1409 ARM. */
1410
1411 /* We should be doing much hairier argument matching (see
1412 section 13.2 of the ARM), but as a quick kludge, just check
1413 for the same type code. */
1414 if (TYPE_CODE (t1[i].type) != TYPE_CODE (value_type (t2[i])))
1415 return i + 1;
1416 }
1417 if (varargs || t2[i] == NULL)
1418 return 0;
1419 return i + 1;
1420 }
1421
1422 /* Helper function used by value_struct_elt to recurse through
1423 baseclasses. Look for a field NAME in ARG1. Adjust the address of
1424 ARG1 by OFFSET bytes, and search in it assuming it has (class) type
1425 TYPE. If found, return value, else return NULL.
1426
1427 If LOOKING_FOR_BASECLASS, then instead of looking for struct
1428 fields, look for a baseclass named NAME. */
1429
1430 static struct value *
1431 search_struct_field (char *name, struct value *arg1, int offset,
1432 struct type *type, int looking_for_baseclass)
1433 {
1434 int i;
1435 int nbases = TYPE_N_BASECLASSES (type);
1436
1437 CHECK_TYPEDEF (type);
1438
1439 if (!looking_for_baseclass)
1440 for (i = TYPE_NFIELDS (type) - 1; i >= nbases; i--)
1441 {
1442 char *t_field_name = TYPE_FIELD_NAME (type, i);
1443
1444 if (t_field_name && (strcmp_iw (t_field_name, name) == 0))
1445 {
1446 struct value *v;
1447 if (TYPE_FIELD_STATIC (type, i))
1448 {
1449 v = value_static_field (type, i);
1450 if (v == 0)
1451 error (_("field %s is nonexistent or has been optimised out"),
1452 name);
1453 }
1454 else
1455 {
1456 v = value_primitive_field (arg1, offset, i, type);
1457 if (v == 0)
1458 error (_("there is no field named %s"), name);
1459 }
1460 return v;
1461 }
1462
1463 if (t_field_name
1464 && (t_field_name[0] == '\0'
1465 || (TYPE_CODE (type) == TYPE_CODE_UNION
1466 && (strcmp_iw (t_field_name, "else") == 0))))
1467 {
1468 struct type *field_type = TYPE_FIELD_TYPE (type, i);
1469 if (TYPE_CODE (field_type) == TYPE_CODE_UNION
1470 || TYPE_CODE (field_type) == TYPE_CODE_STRUCT)
1471 {
1472 /* Look for a match through the fields of an anonymous
1473 union, or anonymous struct. C++ provides anonymous
1474 unions.
1475
1476 In the GNU Chill (now deleted from GDB)
1477 implementation of variant record types, each
1478 <alternative field> has an (anonymous) union type,
1479 each member of the union represents a <variant
1480 alternative>. Each <variant alternative> is
1481 represented as a struct, with a member for each
1482 <variant field>. */
1483
1484 struct value *v;
1485 int new_offset = offset;
1486
1487 /* This is pretty gross. In G++, the offset in an
1488 anonymous union is relative to the beginning of the
1489 enclosing struct. In the GNU Chill (now deleted
1490 from GDB) implementation of variant records, the
1491 bitpos is zero in an anonymous union field, so we
1492 have to add the offset of the union here. */
1493 if (TYPE_CODE (field_type) == TYPE_CODE_STRUCT
1494 || (TYPE_NFIELDS (field_type) > 0
1495 && TYPE_FIELD_BITPOS (field_type, 0) == 0))
1496 new_offset += TYPE_FIELD_BITPOS (type, i) / 8;
1497
1498 v = search_struct_field (name, arg1, new_offset,
1499 field_type,
1500 looking_for_baseclass);
1501 if (v)
1502 return v;
1503 }
1504 }
1505 }
1506
1507 for (i = 0; i < nbases; i++)
1508 {
1509 struct value *v;
1510 struct type *basetype = check_typedef (TYPE_BASECLASS (type, i));
1511 /* If we are looking for baseclasses, this is what we get when
1512 we hit them. But it could happen that the base part's member
1513 name is not yet filled in. */
1514 int found_baseclass = (looking_for_baseclass
1515 && TYPE_BASECLASS_NAME (type, i) != NULL
1516 && (strcmp_iw (name,
1517 TYPE_BASECLASS_NAME (type,
1518 i)) == 0));
1519
1520 if (BASETYPE_VIA_VIRTUAL (type, i))
1521 {
1522 int boffset;
1523 struct value *v2 = allocate_value (basetype);
1524
1525 boffset = baseclass_offset (type, i,
1526 value_contents (arg1) + offset,
1527 VALUE_ADDRESS (arg1)
1528 + value_offset (arg1) + offset);
1529 if (boffset == -1)
1530 error (_("virtual baseclass botch"));
1531
1532 /* The virtual base class pointer might have been clobbered
1533 by the user program. Make sure that it still points to a
1534 valid memory location. */
1535
1536 boffset += offset;
1537 if (boffset < 0 || boffset >= TYPE_LENGTH (type))
1538 {
1539 CORE_ADDR base_addr;
1540
1541 base_addr =
1542 VALUE_ADDRESS (arg1) + value_offset (arg1) + boffset;
1543 if (target_read_memory (base_addr,
1544 value_contents_raw (v2),
1545 TYPE_LENGTH (basetype)) != 0)
1546 error (_("virtual baseclass botch"));
1547 VALUE_LVAL (v2) = lval_memory;
1548 VALUE_ADDRESS (v2) = base_addr;
1549 }
1550 else
1551 {
1552 VALUE_LVAL (v2) = VALUE_LVAL (arg1);
1553 VALUE_ADDRESS (v2) = VALUE_ADDRESS (arg1);
1554 VALUE_FRAME_ID (v2) = VALUE_FRAME_ID (arg1);
1555 set_value_offset (v2, value_offset (arg1) + boffset);
1556 if (VALUE_LVAL (arg1) == lval_memory && value_lazy (arg1))
1557 set_value_lazy (v2, 1);
1558 else
1559 memcpy (value_contents_raw (v2),
1560 value_contents_raw (arg1) + boffset,
1561 TYPE_LENGTH (basetype));
1562 }
1563
1564 if (found_baseclass)
1565 return v2;
1566 v = search_struct_field (name, v2, 0,
1567 TYPE_BASECLASS (type, i),
1568 looking_for_baseclass);
1569 }
1570 else if (found_baseclass)
1571 v = value_primitive_field (arg1, offset, i, type);
1572 else
1573 v = search_struct_field (name, arg1,
1574 offset + TYPE_BASECLASS_BITPOS (type,
1575 i) / 8,
1576 basetype, looking_for_baseclass);
1577 if (v)
1578 return v;
1579 }
1580 return NULL;
1581 }
1582
1583 /* Helper function used by value_struct_elt to recurse through
1584 baseclasses. Look for a field NAME in ARG1. Adjust the address of
1585 ARG1 by OFFSET bytes, and search in it assuming it has (class) type
1586 TYPE.
1587
1588 If found, return value, else if name matched and args not return
1589 (value) -1, else return NULL. */
1590
1591 static struct value *
1592 search_struct_method (char *name, struct value **arg1p,
1593 struct value **args, int offset,
1594 int *static_memfuncp, struct type *type)
1595 {
1596 int i;
1597 struct value *v;
1598 int name_matched = 0;
1599 char dem_opname[64];
1600
1601 CHECK_TYPEDEF (type);
1602 for (i = TYPE_NFN_FIELDS (type) - 1; i >= 0; i--)
1603 {
1604 char *t_field_name = TYPE_FN_FIELDLIST_NAME (type, i);
1605 /* FIXME! May need to check for ARM demangling here */
1606 if (strncmp (t_field_name, "__", 2) == 0 ||
1607 strncmp (t_field_name, "op", 2) == 0 ||
1608 strncmp (t_field_name, "type", 4) == 0)
1609 {
1610 if (cplus_demangle_opname (t_field_name, dem_opname, DMGL_ANSI))
1611 t_field_name = dem_opname;
1612 else if (cplus_demangle_opname (t_field_name, dem_opname, 0))
1613 t_field_name = dem_opname;
1614 }
1615 if (t_field_name && (strcmp_iw (t_field_name, name) == 0))
1616 {
1617 int j = TYPE_FN_FIELDLIST_LENGTH (type, i) - 1;
1618 struct fn_field *f = TYPE_FN_FIELDLIST1 (type, i);
1619 name_matched = 1;
1620
1621 check_stub_method_group (type, i);
1622 if (j > 0 && args == 0)
1623 error (_("cannot resolve overloaded method `%s': no arguments supplied"), name);
1624 else if (j == 0 && args == 0)
1625 {
1626 v = value_fn_field (arg1p, f, j, type, offset);
1627 if (v != NULL)
1628 return v;
1629 }
1630 else
1631 while (j >= 0)
1632 {
1633 if (!typecmp (TYPE_FN_FIELD_STATIC_P (f, j),
1634 TYPE_VARARGS (TYPE_FN_FIELD_TYPE (f, j)),
1635 TYPE_NFIELDS (TYPE_FN_FIELD_TYPE (f, j)),
1636 TYPE_FN_FIELD_ARGS (f, j), args))
1637 {
1638 if (TYPE_FN_FIELD_VIRTUAL_P (f, j))
1639 return value_virtual_fn_field (arg1p, f, j,
1640 type, offset);
1641 if (TYPE_FN_FIELD_STATIC_P (f, j)
1642 && static_memfuncp)
1643 *static_memfuncp = 1;
1644 v = value_fn_field (arg1p, f, j, type, offset);
1645 if (v != NULL)
1646 return v;
1647 }
1648 j--;
1649 }
1650 }
1651 }
1652
1653 for (i = TYPE_N_BASECLASSES (type) - 1; i >= 0; i--)
1654 {
1655 int base_offset;
1656
1657 if (BASETYPE_VIA_VIRTUAL (type, i))
1658 {
1659 struct type *baseclass = check_typedef (TYPE_BASECLASS (type, i));
1660 const gdb_byte *base_valaddr;
1661
1662 /* The virtual base class pointer might have been
1663 clobbered by the user program. Make sure that it
1664 still points to a valid memory location. */
1665
1666 if (offset < 0 || offset >= TYPE_LENGTH (type))
1667 {
1668 gdb_byte *tmp = alloca (TYPE_LENGTH (baseclass));
1669 if (target_read_memory (VALUE_ADDRESS (*arg1p)
1670 + value_offset (*arg1p) + offset,
1671 tmp, TYPE_LENGTH (baseclass)) != 0)
1672 error (_("virtual baseclass botch"));
1673 base_valaddr = tmp;
1674 }
1675 else
1676 base_valaddr = value_contents (*arg1p) + offset;
1677
1678 base_offset = baseclass_offset (type, i, base_valaddr,
1679 VALUE_ADDRESS (*arg1p)
1680 + value_offset (*arg1p) + offset);
1681 if (base_offset == -1)
1682 error (_("virtual baseclass botch"));
1683 }
1684 else
1685 {
1686 base_offset = TYPE_BASECLASS_BITPOS (type, i) / 8;
1687 }
1688 v = search_struct_method (name, arg1p, args, base_offset + offset,
1689 static_memfuncp, TYPE_BASECLASS (type, i));
1690 if (v == (struct value *) - 1)
1691 {
1692 name_matched = 1;
1693 }
1694 else if (v)
1695 {
1696 /* FIXME-bothner: Why is this commented out? Why is it here? */
1697 /* *arg1p = arg1_tmp; */
1698 return v;
1699 }
1700 }
1701 if (name_matched)
1702 return (struct value *) - 1;
1703 else
1704 return NULL;
1705 }
1706
1707 /* Given *ARGP, a value of type (pointer to a)* structure/union,
1708 extract the component named NAME from the ultimate target
1709 structure/union and return it as a value with its appropriate type.
1710 ERR is used in the error message if *ARGP's type is wrong.
1711
1712 C++: ARGS is a list of argument types to aid in the selection of
1713 an appropriate method. Also, handle derived types.
1714
1715 STATIC_MEMFUNCP, if non-NULL, points to a caller-supplied location
1716 where the truthvalue of whether the function that was resolved was
1717 a static member function or not is stored.
1718
1719 ERR is an error message to be printed in case the field is not
1720 found. */
1721
1722 struct value *
1723 value_struct_elt (struct value **argp, struct value **args,
1724 char *name, int *static_memfuncp, char *err)
1725 {
1726 struct type *t;
1727 struct value *v;
1728
1729 *argp = coerce_array (*argp);
1730
1731 t = check_typedef (value_type (*argp));
1732
1733 /* Follow pointers until we get to a non-pointer. */
1734
1735 while (TYPE_CODE (t) == TYPE_CODE_PTR || TYPE_CODE (t) == TYPE_CODE_REF)
1736 {
1737 *argp = value_ind (*argp);
1738 /* Don't coerce fn pointer to fn and then back again! */
1739 if (TYPE_CODE (value_type (*argp)) != TYPE_CODE_FUNC)
1740 *argp = coerce_array (*argp);
1741 t = check_typedef (value_type (*argp));
1742 }
1743
1744 if (TYPE_CODE (t) != TYPE_CODE_STRUCT
1745 && TYPE_CODE (t) != TYPE_CODE_UNION)
1746 error (_("Attempt to extract a component of a value that is not a %s."), err);
1747
1748 /* Assume it's not, unless we see that it is. */
1749 if (static_memfuncp)
1750 *static_memfuncp = 0;
1751
1752 if (!args)
1753 {
1754 /* if there are no arguments ...do this... */
1755
1756 /* Try as a field first, because if we succeed, there is less
1757 work to be done. */
1758 v = search_struct_field (name, *argp, 0, t, 0);
1759 if (v)
1760 return v;
1761
1762 /* C++: If it was not found as a data field, then try to
1763 return it as a pointer to a method. */
1764
1765 if (destructor_name_p (name, t))
1766 error (_("Cannot get value of destructor"));
1767
1768 v = search_struct_method (name, argp, args, 0,
1769 static_memfuncp, t);
1770
1771 if (v == (struct value *) - 1)
1772 error (_("Cannot take address of method %s."), name);
1773 else if (v == 0)
1774 {
1775 if (TYPE_NFN_FIELDS (t))
1776 error (_("There is no member or method named %s."), name);
1777 else
1778 error (_("There is no member named %s."), name);
1779 }
1780 return v;
1781 }
1782
1783 if (destructor_name_p (name, t))
1784 {
1785 if (!args[1])
1786 {
1787 /* Destructors are a special case. */
1788 int m_index, f_index;
1789
1790 v = NULL;
1791 if (get_destructor_fn_field (t, &m_index, &f_index))
1792 {
1793 v = value_fn_field (NULL,
1794 TYPE_FN_FIELDLIST1 (t, m_index),
1795 f_index, NULL, 0);
1796 }
1797 if (v == NULL)
1798 error (_("could not find destructor function named %s."),
1799 name);
1800 else
1801 return v;
1802 }
1803 else
1804 {
1805 error (_("destructor should not have any argument"));
1806 }
1807 }
1808 else
1809 v = search_struct_method (name, argp, args, 0,
1810 static_memfuncp, t);
1811
1812 if (v == (struct value *) - 1)
1813 {
1814 error (_("One of the arguments you tried to pass to %s could not be converted to what the function wants."), name);
1815 }
1816 else if (v == 0)
1817 {
1818 /* See if user tried to invoke data as function. If so, hand it
1819 back. If it's not callable (i.e., a pointer to function),
1820 gdb should give an error. */
1821 v = search_struct_field (name, *argp, 0, t, 0);
1822 }
1823
1824 if (!v)
1825 error (_("Structure has no component named %s."), name);
1826 return v;
1827 }
1828
1829 /* Search through the methods of an object (and its bases) to find a
1830 specified method. Return the pointer to the fn_field list of
1831 overloaded instances.
1832
1833 Helper function for value_find_oload_list.
1834 ARGP is a pointer to a pointer to a value (the object).
1835 METHOD is a string containing the method name.
1836 OFFSET is the offset within the value.
1837 TYPE is the assumed type of the object.
1838 NUM_FNS is the number of overloaded instances.
1839 BASETYPE is set to the actual type of the subobject where the
1840 method is found.
1841 BOFFSET is the offset of the base subobject where the method is found.
1842 */
1843
1844 static struct fn_field *
1845 find_method_list (struct value **argp, char *method,
1846 int offset, struct type *type, int *num_fns,
1847 struct type **basetype, int *boffset)
1848 {
1849 int i;
1850 struct fn_field *f;
1851 CHECK_TYPEDEF (type);
1852
1853 *num_fns = 0;
1854
1855 /* First check in object itself. */
1856 for (i = TYPE_NFN_FIELDS (type) - 1; i >= 0; i--)
1857 {
1858 /* pai: FIXME What about operators and type conversions? */
1859 char *fn_field_name = TYPE_FN_FIELDLIST_NAME (type, i);
1860 if (fn_field_name && (strcmp_iw (fn_field_name, method) == 0))
1861 {
1862 int len = TYPE_FN_FIELDLIST_LENGTH (type, i);
1863 struct fn_field *f = TYPE_FN_FIELDLIST1 (type, i);
1864
1865 *num_fns = len;
1866 *basetype = type;
1867 *boffset = offset;
1868
1869 /* Resolve any stub methods. */
1870 check_stub_method_group (type, i);
1871
1872 return f;
1873 }
1874 }
1875
1876 /* Not found in object, check in base subobjects. */
1877 for (i = TYPE_N_BASECLASSES (type) - 1; i >= 0; i--)
1878 {
1879 int base_offset;
1880 if (BASETYPE_VIA_VIRTUAL (type, i))
1881 {
1882 base_offset = value_offset (*argp) + offset;
1883 base_offset = baseclass_offset (type, i,
1884 value_contents (*argp) + base_offset,
1885 VALUE_ADDRESS (*argp) + base_offset);
1886 if (base_offset == -1)
1887 error (_("virtual baseclass botch"));
1888 }
1889 else /* Non-virtual base, simply use bit position from debug
1890 info. */
1891 {
1892 base_offset = TYPE_BASECLASS_BITPOS (type, i) / 8;
1893 }
1894 f = find_method_list (argp, method, base_offset + offset,
1895 TYPE_BASECLASS (type, i), num_fns,
1896 basetype, boffset);
1897 if (f)
1898 return f;
1899 }
1900 return NULL;
1901 }
1902
1903 /* Return the list of overloaded methods of a specified name.
1904
1905 ARGP is a pointer to a pointer to a value (the object).
1906 METHOD is the method name.
1907 OFFSET is the offset within the value contents.
1908 NUM_FNS is the number of overloaded instances.
1909 BASETYPE is set to the type of the base subobject that defines the
1910 method.
1911 BOFFSET is the offset of the base subobject which defines the method.
1912 */
1913
1914 struct fn_field *
1915 value_find_oload_method_list (struct value **argp, char *method,
1916 int offset, int *num_fns,
1917 struct type **basetype, int *boffset)
1918 {
1919 struct type *t;
1920
1921 t = check_typedef (value_type (*argp));
1922
1923 /* Code snarfed from value_struct_elt. */
1924 while (TYPE_CODE (t) == TYPE_CODE_PTR || TYPE_CODE (t) == TYPE_CODE_REF)
1925 {
1926 *argp = value_ind (*argp);
1927 /* Don't coerce fn pointer to fn and then back again! */
1928 if (TYPE_CODE (value_type (*argp)) != TYPE_CODE_FUNC)
1929 *argp = coerce_array (*argp);
1930 t = check_typedef (value_type (*argp));
1931 }
1932
1933 if (TYPE_CODE (t) != TYPE_CODE_STRUCT
1934 && TYPE_CODE (t) != TYPE_CODE_UNION)
1935 error (_("Attempt to extract a component of a value that is not a struct or union"));
1936
1937 return find_method_list (argp, method, 0, t, num_fns,
1938 basetype, boffset);
1939 }
1940
1941 /* Given an array of argument types (ARGTYPES) (which includes an
1942 entry for "this" in the case of C++ methods), the number of
1943 arguments NARGS, the NAME of a function whether it's a method or
1944 not (METHOD), and the degree of laxness (LAX) in conforming to
1945 overload resolution rules in ANSI C++, find the best function that
1946 matches on the argument types according to the overload resolution
1947 rules.
1948
1949 In the case of class methods, the parameter OBJ is an object value
1950 in which to search for overloaded methods.
1951
1952 In the case of non-method functions, the parameter FSYM is a symbol
1953 corresponding to one of the overloaded functions.
1954
1955 Return value is an integer: 0 -> good match, 10 -> debugger applied
1956 non-standard coercions, 100 -> incompatible.
1957
1958 If a method is being searched for, VALP will hold the value.
1959 If a non-method is being searched for, SYMP will hold the symbol
1960 for it.
1961
1962 If a method is being searched for, and it is a static method,
1963 then STATICP will point to a non-zero value.
1964
1965 Note: This function does *not* check the value of
1966 overload_resolution. Caller must check it to see whether overload
1967 resolution is permitted.
1968 */
1969
1970 int
1971 find_overload_match (struct type **arg_types, int nargs,
1972 char *name, int method, int lax,
1973 struct value **objp, struct symbol *fsym,
1974 struct value **valp, struct symbol **symp,
1975 int *staticp)
1976 {
1977 struct value *obj = (objp ? *objp : NULL);
1978 /* Index of best overloaded function. */
1979 int oload_champ;
1980 /* The measure for the current best match. */
1981 struct badness_vector *oload_champ_bv = NULL;
1982 struct value *temp = obj;
1983 /* For methods, the list of overloaded methods. */
1984 struct fn_field *fns_ptr = NULL;
1985 /* For non-methods, the list of overloaded function symbols. */
1986 struct symbol **oload_syms = NULL;
1987 /* Number of overloaded instances being considered. */
1988 int num_fns = 0;
1989 struct type *basetype = NULL;
1990 int boffset;
1991 int ix;
1992 int static_offset;
1993 struct cleanup *old_cleanups = NULL;
1994
1995 const char *obj_type_name = NULL;
1996 char *func_name = NULL;
1997 enum oload_classification match_quality;
1998
1999 /* Get the list of overloaded methods or functions. */
2000 if (method)
2001 {
2002 gdb_assert (obj);
2003 obj_type_name = TYPE_NAME (value_type (obj));
2004 /* Hack: evaluate_subexp_standard often passes in a pointer
2005 value rather than the object itself, so try again. */
2006 if ((!obj_type_name || !*obj_type_name)
2007 && (TYPE_CODE (value_type (obj)) == TYPE_CODE_PTR))
2008 obj_type_name = TYPE_NAME (TYPE_TARGET_TYPE (value_type (obj)));
2009
2010 fns_ptr = value_find_oload_method_list (&temp, name,
2011 0, &num_fns,
2012 &basetype, &boffset);
2013 if (!fns_ptr || !num_fns)
2014 error (_("Couldn't find method %s%s%s"),
2015 obj_type_name,
2016 (obj_type_name && *obj_type_name) ? "::" : "",
2017 name);
2018 /* If we are dealing with stub method types, they should have
2019 been resolved by find_method_list via
2020 value_find_oload_method_list above. */
2021 gdb_assert (TYPE_DOMAIN_TYPE (fns_ptr[0].type) != NULL);
2022 oload_champ = find_oload_champ (arg_types, nargs, method,
2023 num_fns, fns_ptr,
2024 oload_syms, &oload_champ_bv);
2025 }
2026 else
2027 {
2028 const char *qualified_name = SYMBOL_CPLUS_DEMANGLED_NAME (fsym);
2029
2030 /* If we have a C++ name, try to extract just the function
2031 part. */
2032 if (qualified_name)
2033 func_name = cp_func_name (qualified_name);
2034
2035 /* If there was no C++ name, this must be a C-style function.
2036 Just return the same symbol. Do the same if cp_func_name
2037 fails for some reason. */
2038 if (func_name == NULL)
2039 {
2040 *symp = fsym;
2041 return 0;
2042 }
2043
2044 old_cleanups = make_cleanup (xfree, func_name);
2045 make_cleanup (xfree, oload_syms);
2046 make_cleanup (xfree, oload_champ_bv);
2047
2048 oload_champ = find_oload_champ_namespace (arg_types, nargs,
2049 func_name,
2050 qualified_name,
2051 &oload_syms,
2052 &oload_champ_bv);
2053 }
2054
2055 /* Check how bad the best match is. */
2056
2057 match_quality =
2058 classify_oload_match (oload_champ_bv, nargs,
2059 oload_method_static (method, fns_ptr,
2060 oload_champ));
2061
2062 if (match_quality == INCOMPATIBLE)
2063 {
2064 if (method)
2065 error (_("Cannot resolve method %s%s%s to any overloaded instance"),
2066 obj_type_name,
2067 (obj_type_name && *obj_type_name) ? "::" : "",
2068 name);
2069 else
2070 error (_("Cannot resolve function %s to any overloaded instance"),
2071 func_name);
2072 }
2073 else if (match_quality == NON_STANDARD)
2074 {
2075 if (method)
2076 warning (_("Using non-standard conversion to match method %s%s%s to supplied arguments"),
2077 obj_type_name,
2078 (obj_type_name && *obj_type_name) ? "::" : "",
2079 name);
2080 else
2081 warning (_("Using non-standard conversion to match function %s to supplied arguments"),
2082 func_name);
2083 }
2084
2085 if (method)
2086 {
2087 if (staticp != NULL)
2088 *staticp = oload_method_static (method, fns_ptr, oload_champ);
2089 if (TYPE_FN_FIELD_VIRTUAL_P (fns_ptr, oload_champ))
2090 *valp = value_virtual_fn_field (&temp, fns_ptr, oload_champ,
2091 basetype, boffset);
2092 else
2093 *valp = value_fn_field (&temp, fns_ptr, oload_champ,
2094 basetype, boffset);
2095 }
2096 else
2097 {
2098 *symp = oload_syms[oload_champ];
2099 }
2100
2101 if (objp)
2102 {
2103 if (TYPE_CODE (value_type (temp)) != TYPE_CODE_PTR
2104 && TYPE_CODE (value_type (*objp)) == TYPE_CODE_PTR)
2105 {
2106 temp = value_addr (temp);
2107 }
2108 *objp = temp;
2109 }
2110 if (old_cleanups != NULL)
2111 do_cleanups (old_cleanups);
2112
2113 switch (match_quality)
2114 {
2115 case INCOMPATIBLE:
2116 return 100;
2117 case NON_STANDARD:
2118 return 10;
2119 default: /* STANDARD */
2120 return 0;
2121 }
2122 }
2123
2124 /* Find the best overload match, searching for FUNC_NAME in namespaces
2125 contained in QUALIFIED_NAME until it either finds a good match or
2126 runs out of namespaces. It stores the overloaded functions in
2127 *OLOAD_SYMS, and the badness vector in *OLOAD_CHAMP_BV. The
2128 calling function is responsible for freeing *OLOAD_SYMS and
2129 *OLOAD_CHAMP_BV. */
2130
2131 static int
2132 find_oload_champ_namespace (struct type **arg_types, int nargs,
2133 const char *func_name,
2134 const char *qualified_name,
2135 struct symbol ***oload_syms,
2136 struct badness_vector **oload_champ_bv)
2137 {
2138 int oload_champ;
2139
2140 find_oload_champ_namespace_loop (arg_types, nargs,
2141 func_name,
2142 qualified_name, 0,
2143 oload_syms, oload_champ_bv,
2144 &oload_champ);
2145
2146 return oload_champ;
2147 }
2148
2149 /* Helper function for find_oload_champ_namespace; NAMESPACE_LEN is
2150 how deep we've looked for namespaces, and the champ is stored in
2151 OLOAD_CHAMP. The return value is 1 if the champ is a good one, 0
2152 if it isn't.
2153
2154 It is the caller's responsibility to free *OLOAD_SYMS and
2155 *OLOAD_CHAMP_BV. */
2156
2157 static int
2158 find_oload_champ_namespace_loop (struct type **arg_types, int nargs,
2159 const char *func_name,
2160 const char *qualified_name,
2161 int namespace_len,
2162 struct symbol ***oload_syms,
2163 struct badness_vector **oload_champ_bv,
2164 int *oload_champ)
2165 {
2166 int next_namespace_len = namespace_len;
2167 int searched_deeper = 0;
2168 int num_fns = 0;
2169 struct cleanup *old_cleanups;
2170 int new_oload_champ;
2171 struct symbol **new_oload_syms;
2172 struct badness_vector *new_oload_champ_bv;
2173 char *new_namespace;
2174
2175 if (next_namespace_len != 0)
2176 {
2177 gdb_assert (qualified_name[next_namespace_len] == ':');
2178 next_namespace_len += 2;
2179 }
2180 next_namespace_len +=
2181 cp_find_first_component (qualified_name + next_namespace_len);
2182
2183 /* Initialize these to values that can safely be xfree'd. */
2184 *oload_syms = NULL;
2185 *oload_champ_bv = NULL;
2186
2187 /* First, see if we have a deeper namespace we can search in.
2188 If we get a good match there, use it. */
2189
2190 if (qualified_name[next_namespace_len] == ':')
2191 {
2192 searched_deeper = 1;
2193
2194 if (find_oload_champ_namespace_loop (arg_types, nargs,
2195 func_name, qualified_name,
2196 next_namespace_len,
2197 oload_syms, oload_champ_bv,
2198 oload_champ))
2199 {
2200 return 1;
2201 }
2202 };
2203
2204 /* If we reach here, either we're in the deepest namespace or we
2205 didn't find a good match in a deeper namespace. But, in the
2206 latter case, we still have a bad match in a deeper namespace;
2207 note that we might not find any match at all in the current
2208 namespace. (There's always a match in the deepest namespace,
2209 because this overload mechanism only gets called if there's a
2210 function symbol to start off with.) */
2211
2212 old_cleanups = make_cleanup (xfree, *oload_syms);
2213 old_cleanups = make_cleanup (xfree, *oload_champ_bv);
2214 new_namespace = alloca (namespace_len + 1);
2215 strncpy (new_namespace, qualified_name, namespace_len);
2216 new_namespace[namespace_len] = '\0';
2217 new_oload_syms = make_symbol_overload_list (func_name,
2218 new_namespace);
2219 while (new_oload_syms[num_fns])
2220 ++num_fns;
2221
2222 new_oload_champ = find_oload_champ (arg_types, nargs, 0, num_fns,
2223 NULL, new_oload_syms,
2224 &new_oload_champ_bv);
2225
2226 /* Case 1: We found a good match. Free earlier matches (if any),
2227 and return it. Case 2: We didn't find a good match, but we're
2228 not the deepest function. Then go with the bad match that the
2229 deeper function found. Case 3: We found a bad match, and we're
2230 the deepest function. Then return what we found, even though
2231 it's a bad match. */
2232
2233 if (new_oload_champ != -1
2234 && classify_oload_match (new_oload_champ_bv, nargs, 0) == STANDARD)
2235 {
2236 *oload_syms = new_oload_syms;
2237 *oload_champ = new_oload_champ;
2238 *oload_champ_bv = new_oload_champ_bv;
2239 do_cleanups (old_cleanups);
2240 return 1;
2241 }
2242 else if (searched_deeper)
2243 {
2244 xfree (new_oload_syms);
2245 xfree (new_oload_champ_bv);
2246 discard_cleanups (old_cleanups);
2247 return 0;
2248 }
2249 else
2250 {
2251 gdb_assert (new_oload_champ != -1);
2252 *oload_syms = new_oload_syms;
2253 *oload_champ = new_oload_champ;
2254 *oload_champ_bv = new_oload_champ_bv;
2255 discard_cleanups (old_cleanups);
2256 return 0;
2257 }
2258 }
2259
2260 /* Look for a function to take NARGS args of types ARG_TYPES. Find
2261 the best match from among the overloaded methods or functions
2262 (depending on METHOD) given by FNS_PTR or OLOAD_SYMS, respectively.
2263 The number of methods/functions in the list is given by NUM_FNS.
2264 Return the index of the best match; store an indication of the
2265 quality of the match in OLOAD_CHAMP_BV.
2266
2267 It is the caller's responsibility to free *OLOAD_CHAMP_BV. */
2268
2269 static int
2270 find_oload_champ (struct type **arg_types, int nargs, int method,
2271 int num_fns, struct fn_field *fns_ptr,
2272 struct symbol **oload_syms,
2273 struct badness_vector **oload_champ_bv)
2274 {
2275 int ix;
2276 /* A measure of how good an overloaded instance is. */
2277 struct badness_vector *bv;
2278 /* Index of best overloaded function. */
2279 int oload_champ = -1;
2280 /* Current ambiguity state for overload resolution. */
2281 int oload_ambiguous = 0;
2282 /* 0 => no ambiguity, 1 => two good funcs, 2 => incomparable funcs. */
2283
2284 *oload_champ_bv = NULL;
2285
2286 /* Consider each candidate in turn. */
2287 for (ix = 0; ix < num_fns; ix++)
2288 {
2289 int jj;
2290 int static_offset = oload_method_static (method, fns_ptr, ix);
2291 int nparms;
2292 struct type **parm_types;
2293
2294 if (method)
2295 {
2296 nparms = TYPE_NFIELDS (TYPE_FN_FIELD_TYPE (fns_ptr, ix));
2297 }
2298 else
2299 {
2300 /* If it's not a method, this is the proper place. */
2301 nparms = TYPE_NFIELDS (SYMBOL_TYPE (oload_syms[ix]));
2302 }
2303
2304 /* Prepare array of parameter types. */
2305 parm_types = (struct type **)
2306 xmalloc (nparms * (sizeof (struct type *)));
2307 for (jj = 0; jj < nparms; jj++)
2308 parm_types[jj] = (method
2309 ? (TYPE_FN_FIELD_ARGS (fns_ptr, ix)[jj].type)
2310 : TYPE_FIELD_TYPE (SYMBOL_TYPE (oload_syms[ix]),
2311 jj));
2312
2313 /* Compare parameter types to supplied argument types. Skip
2314 THIS for static methods. */
2315 bv = rank_function (parm_types, nparms,
2316 arg_types + static_offset,
2317 nargs - static_offset);
2318
2319 if (!*oload_champ_bv)
2320 {
2321 *oload_champ_bv = bv;
2322 oload_champ = 0;
2323 }
2324 else /* See whether current candidate is better or worse than
2325 previous best. */
2326 switch (compare_badness (bv, *oload_champ_bv))
2327 {
2328 case 0: /* Top two contenders are equally good. */
2329 oload_ambiguous = 1;
2330 break;
2331 case 1: /* Incomparable top contenders. */
2332 oload_ambiguous = 2;
2333 break;
2334 case 2: /* New champion, record details. */
2335 *oload_champ_bv = bv;
2336 oload_ambiguous = 0;
2337 oload_champ = ix;
2338 break;
2339 case 3:
2340 default:
2341 break;
2342 }
2343 xfree (parm_types);
2344 if (overload_debug)
2345 {
2346 if (method)
2347 fprintf_filtered (gdb_stderr,
2348 "Overloaded method instance %s, # of parms %d\n",
2349 fns_ptr[ix].physname, nparms);
2350 else
2351 fprintf_filtered (gdb_stderr,
2352 "Overloaded function instance %s # of parms %d\n",
2353 SYMBOL_DEMANGLED_NAME (oload_syms[ix]),
2354 nparms);
2355 for (jj = 0; jj < nargs - static_offset; jj++)
2356 fprintf_filtered (gdb_stderr,
2357 "...Badness @ %d : %d\n",
2358 jj, bv->rank[jj]);
2359 fprintf_filtered (gdb_stderr,
2360 "Overload resolution champion is %d, ambiguous? %d\n",
2361 oload_champ, oload_ambiguous);
2362 }
2363 }
2364
2365 return oload_champ;
2366 }
2367
2368 /* Return 1 if we're looking at a static method, 0 if we're looking at
2369 a non-static method or a function that isn't a method. */
2370
2371 static int
2372 oload_method_static (int method, struct fn_field *fns_ptr, int index)
2373 {
2374 if (method && TYPE_FN_FIELD_STATIC_P (fns_ptr, index))
2375 return 1;
2376 else
2377 return 0;
2378 }
2379
2380 /* Check how good an overload match OLOAD_CHAMP_BV represents. */
2381
2382 static enum oload_classification
2383 classify_oload_match (struct badness_vector *oload_champ_bv,
2384 int nargs,
2385 int static_offset)
2386 {
2387 int ix;
2388
2389 for (ix = 1; ix <= nargs - static_offset; ix++)
2390 {
2391 if (oload_champ_bv->rank[ix] >= 100)
2392 return INCOMPATIBLE; /* Truly mismatched types. */
2393 else if (oload_champ_bv->rank[ix] >= 10)
2394 return NON_STANDARD; /* Non-standard type conversions
2395 needed. */
2396 }
2397
2398 return STANDARD; /* Only standard conversions needed. */
2399 }
2400
2401 /* C++: return 1 is NAME is a legitimate name for the destructor of
2402 type TYPE. If TYPE does not have a destructor, or if NAME is
2403 inappropriate for TYPE, an error is signaled. */
2404 int
2405 destructor_name_p (const char *name, const struct type *type)
2406 {
2407 /* Destructors are a special case. */
2408
2409 if (name[0] == '~')
2410 {
2411 char *dname = type_name_no_tag (type);
2412 char *cp = strchr (dname, '<');
2413 unsigned int len;
2414
2415 /* Do not compare the template part for template classes. */
2416 if (cp == NULL)
2417 len = strlen (dname);
2418 else
2419 len = cp - dname;
2420 if (strlen (name + 1) != len || strncmp (dname, name + 1, len) != 0)
2421 error (_("name of destructor must equal name of class"));
2422 else
2423 return 1;
2424 }
2425 return 0;
2426 }
2427
2428 /* Given TYPE, a structure/union,
2429 return 1 if the component named NAME from the ultimate target
2430 structure/union is defined, otherwise, return 0. */
2431
2432 int
2433 check_field (struct type *type, const char *name)
2434 {
2435 int i;
2436
2437 for (i = TYPE_NFIELDS (type) - 1; i >= TYPE_N_BASECLASSES (type); i--)
2438 {
2439 char *t_field_name = TYPE_FIELD_NAME (type, i);
2440 if (t_field_name && (strcmp_iw (t_field_name, name) == 0))
2441 return 1;
2442 }
2443
2444 /* C++: If it was not found as a data field, then try to return it
2445 as a pointer to a method. */
2446
2447 /* Destructors are a special case. */
2448 if (destructor_name_p (name, type))
2449 {
2450 int m_index, f_index;
2451
2452 return get_destructor_fn_field (type, &m_index, &f_index);
2453 }
2454
2455 for (i = TYPE_NFN_FIELDS (type) - 1; i >= 0; --i)
2456 {
2457 if (strcmp_iw (TYPE_FN_FIELDLIST_NAME (type, i), name) == 0)
2458 return 1;
2459 }
2460
2461 for (i = TYPE_N_BASECLASSES (type) - 1; i >= 0; i--)
2462 if (check_field (TYPE_BASECLASS (type, i), name))
2463 return 1;
2464
2465 return 0;
2466 }
2467
2468 /* C++: Given an aggregate type CURTYPE, and a member name NAME,
2469 return the appropriate member (or the address of the member, if
2470 WANT_ADDRESS). This function is used to resolve user expressions
2471 of the form "DOMAIN::NAME". For more details on what happens, see
2472 the comment before value_struct_elt_for_reference. */
2473
2474 struct value *
2475 value_aggregate_elt (struct type *curtype,
2476 char *name, int want_address,
2477 enum noside noside)
2478 {
2479 switch (TYPE_CODE (curtype))
2480 {
2481 case TYPE_CODE_STRUCT:
2482 case TYPE_CODE_UNION:
2483 return value_struct_elt_for_reference (curtype, 0, curtype,
2484 name, NULL,
2485 want_address, noside);
2486 case TYPE_CODE_NAMESPACE:
2487 return value_namespace_elt (curtype, name,
2488 want_address, noside);
2489 default:
2490 internal_error (__FILE__, __LINE__,
2491 _("non-aggregate type in value_aggregate_elt"));
2492 }
2493 }
2494
2495 /* C++: Given an aggregate type CURTYPE, and a member name NAME,
2496 return the address of this member as a "pointer to member" type.
2497 If INTYPE is non-null, then it will be the type of the member we
2498 are looking for. This will help us resolve "pointers to member
2499 functions". This function is used to resolve user expressions of
2500 the form "DOMAIN::NAME". */
2501
2502 static struct value *
2503 value_struct_elt_for_reference (struct type *domain, int offset,
2504 struct type *curtype, char *name,
2505 struct type *intype,
2506 int want_address,
2507 enum noside noside)
2508 {
2509 struct type *t = curtype;
2510 int i;
2511 struct value *v, *result;
2512
2513 if (TYPE_CODE (t) != TYPE_CODE_STRUCT
2514 && TYPE_CODE (t) != TYPE_CODE_UNION)
2515 error (_("Internal error: non-aggregate type to value_struct_elt_for_reference"));
2516
2517 for (i = TYPE_NFIELDS (t) - 1; i >= TYPE_N_BASECLASSES (t); i--)
2518 {
2519 char *t_field_name = TYPE_FIELD_NAME (t, i);
2520
2521 if (t_field_name && strcmp (t_field_name, name) == 0)
2522 {
2523 if (TYPE_FIELD_STATIC (t, i))
2524 {
2525 v = value_static_field (t, i);
2526 if (v == NULL)
2527 error (_("static field %s has been optimized out"),
2528 name);
2529 if (want_address)
2530 v = value_addr (v);
2531 return v;
2532 }
2533 if (TYPE_FIELD_PACKED (t, i))
2534 error (_("pointers to bitfield members not allowed"));
2535
2536 if (want_address)
2537 return value_from_longest
2538 (lookup_memberptr_type (TYPE_FIELD_TYPE (t, i), domain),
2539 offset + (LONGEST) (TYPE_FIELD_BITPOS (t, i) >> 3));
2540 else if (noside == EVAL_AVOID_SIDE_EFFECTS)
2541 return allocate_value (TYPE_FIELD_TYPE (t, i));
2542 else
2543 error (_("Cannot reference non-static field \"%s\""), name);
2544 }
2545 }
2546
2547 /* C++: If it was not found as a data field, then try to return it
2548 as a pointer to a method. */
2549
2550 /* Destructors are a special case. */
2551 if (destructor_name_p (name, t))
2552 {
2553 error (_("member pointers to destructors not implemented yet"));
2554 }
2555
2556 /* Perform all necessary dereferencing. */
2557 while (intype && TYPE_CODE (intype) == TYPE_CODE_PTR)
2558 intype = TYPE_TARGET_TYPE (intype);
2559
2560 for (i = TYPE_NFN_FIELDS (t) - 1; i >= 0; --i)
2561 {
2562 char *t_field_name = TYPE_FN_FIELDLIST_NAME (t, i);
2563 char dem_opname[64];
2564
2565 if (strncmp (t_field_name, "__", 2) == 0
2566 || strncmp (t_field_name, "op", 2) == 0
2567 || strncmp (t_field_name, "type", 4) == 0)
2568 {
2569 if (cplus_demangle_opname (t_field_name,
2570 dem_opname, DMGL_ANSI))
2571 t_field_name = dem_opname;
2572 else if (cplus_demangle_opname (t_field_name,
2573 dem_opname, 0))
2574 t_field_name = dem_opname;
2575 }
2576 if (t_field_name && strcmp (t_field_name, name) == 0)
2577 {
2578 int j = TYPE_FN_FIELDLIST_LENGTH (t, i);
2579 struct fn_field *f = TYPE_FN_FIELDLIST1 (t, i);
2580
2581 check_stub_method_group (t, i);
2582
2583 if (intype == 0 && j > 1)
2584 error (_("non-unique member `%s' requires type instantiation"), name);
2585 if (intype)
2586 {
2587 while (j--)
2588 if (TYPE_FN_FIELD_TYPE (f, j) == intype)
2589 break;
2590 if (j < 0)
2591 error (_("no member function matches that type instantiation"));
2592 }
2593 else
2594 j = 0;
2595
2596 if (TYPE_FN_FIELD_STATIC_P (f, j))
2597 {
2598 struct symbol *s =
2599 lookup_symbol (TYPE_FN_FIELD_PHYSNAME (f, j),
2600 0, VAR_DOMAIN, 0, NULL);
2601 if (s == NULL)
2602 return NULL;
2603
2604 if (want_address)
2605 return value_addr (read_var_value (s, 0));
2606 else
2607 return read_var_value (s, 0);
2608 }
2609
2610 if (TYPE_FN_FIELD_VIRTUAL_P (f, j))
2611 {
2612 if (want_address)
2613 {
2614 result = allocate_value
2615 (lookup_methodptr_type (TYPE_FN_FIELD_TYPE (f, j)));
2616 cplus_make_method_ptr (value_contents_writeable (result),
2617 TYPE_FN_FIELD_VOFFSET (f, j), 1);
2618 }
2619 else if (noside == EVAL_AVOID_SIDE_EFFECTS)
2620 return allocate_value (TYPE_FN_FIELD_TYPE (f, j));
2621 else
2622 error (_("Cannot reference virtual member function \"%s\""),
2623 name);
2624 }
2625 else
2626 {
2627 struct symbol *s =
2628 lookup_symbol (TYPE_FN_FIELD_PHYSNAME (f, j),
2629 0, VAR_DOMAIN, 0, NULL);
2630 if (s == NULL)
2631 return NULL;
2632
2633 v = read_var_value (s, 0);
2634 if (!want_address)
2635 result = v;
2636 else
2637 {
2638 result = allocate_value (lookup_methodptr_type (TYPE_FN_FIELD_TYPE (f, j)));
2639 cplus_make_method_ptr (value_contents_writeable (result),
2640 VALUE_ADDRESS (v), 0);
2641 }
2642 }
2643 return result;
2644 }
2645 }
2646 for (i = TYPE_N_BASECLASSES (t) - 1; i >= 0; i--)
2647 {
2648 struct value *v;
2649 int base_offset;
2650
2651 if (BASETYPE_VIA_VIRTUAL (t, i))
2652 base_offset = 0;
2653 else
2654 base_offset = TYPE_BASECLASS_BITPOS (t, i) / 8;
2655 v = value_struct_elt_for_reference (domain,
2656 offset + base_offset,
2657 TYPE_BASECLASS (t, i),
2658 name, intype,
2659 want_address, noside);
2660 if (v)
2661 return v;
2662 }
2663
2664 /* As a last chance, pretend that CURTYPE is a namespace, and look
2665 it up that way; this (frequently) works for types nested inside
2666 classes. */
2667
2668 return value_maybe_namespace_elt (curtype, name,
2669 want_address, noside);
2670 }
2671
2672 /* C++: Return the member NAME of the namespace given by the type
2673 CURTYPE. */
2674
2675 static struct value *
2676 value_namespace_elt (const struct type *curtype,
2677 char *name, int want_address,
2678 enum noside noside)
2679 {
2680 struct value *retval = value_maybe_namespace_elt (curtype, name,
2681 want_address,
2682 noside);
2683
2684 if (retval == NULL)
2685 error (_("No symbol \"%s\" in namespace \"%s\"."),
2686 name, TYPE_TAG_NAME (curtype));
2687
2688 return retval;
2689 }
2690
2691 /* A helper function used by value_namespace_elt and
2692 value_struct_elt_for_reference. It looks up NAME inside the
2693 context CURTYPE; this works if CURTYPE is a namespace or if CURTYPE
2694 is a class and NAME refers to a type in CURTYPE itself (as opposed
2695 to, say, some base class of CURTYPE). */
2696
2697 static struct value *
2698 value_maybe_namespace_elt (const struct type *curtype,
2699 char *name, int want_address,
2700 enum noside noside)
2701 {
2702 const char *namespace_name = TYPE_TAG_NAME (curtype);
2703 struct symbol *sym;
2704 struct value *result;
2705
2706 sym = cp_lookup_symbol_namespace (namespace_name, name, NULL,
2707 get_selected_block (0),
2708 VAR_DOMAIN, NULL);
2709
2710 if (sym == NULL)
2711 return NULL;
2712 else if ((noside == EVAL_AVOID_SIDE_EFFECTS)
2713 && (SYMBOL_CLASS (sym) == LOC_TYPEDEF))
2714 result = allocate_value (SYMBOL_TYPE (sym));
2715 else
2716 result = value_of_variable (sym, get_selected_block (0));
2717
2718 if (result && want_address)
2719 result = value_addr (result);
2720
2721 return result;
2722 }
2723
2724 /* Given a pointer value V, find the real (RTTI) type of the object it
2725 points to.
2726
2727 Other parameters FULL, TOP, USING_ENC as with value_rtti_type()
2728 and refer to the values computed for the object pointed to. */
2729
2730 struct type *
2731 value_rtti_target_type (struct value *v, int *full,
2732 int *top, int *using_enc)
2733 {
2734 struct value *target;
2735
2736 target = value_ind (v);
2737
2738 return value_rtti_type (target, full, top, using_enc);
2739 }
2740
2741 /* Given a value pointed to by ARGP, check its real run-time type, and
2742 if that is different from the enclosing type, create a new value
2743 using the real run-time type as the enclosing type (and of the same
2744 type as ARGP) and return it, with the embedded offset adjusted to
2745 be the correct offset to the enclosed object. RTYPE is the type,
2746 and XFULL, XTOP, and XUSING_ENC are the other parameters, computed
2747 by value_rtti_type(). If these are available, they can be supplied
2748 and a second call to value_rtti_type() is avoided. (Pass RTYPE ==
2749 NULL if they're not available. */
2750
2751 struct value *
2752 value_full_object (struct value *argp,
2753 struct type *rtype,
2754 int xfull, int xtop,
2755 int xusing_enc)
2756 {
2757 struct type *real_type;
2758 int full = 0;
2759 int top = -1;
2760 int using_enc = 0;
2761 struct value *new_val;
2762
2763 if (rtype)
2764 {
2765 real_type = rtype;
2766 full = xfull;
2767 top = xtop;
2768 using_enc = xusing_enc;
2769 }
2770 else
2771 real_type = value_rtti_type (argp, &full, &top, &using_enc);
2772
2773 /* If no RTTI data, or if object is already complete, do nothing. */
2774 if (!real_type || real_type == value_enclosing_type (argp))
2775 return argp;
2776
2777 /* If we have the full object, but for some reason the enclosing
2778 type is wrong, set it. */
2779 /* pai: FIXME -- sounds iffy */
2780 if (full)
2781 {
2782 argp = value_change_enclosing_type (argp, real_type);
2783 return argp;
2784 }
2785
2786 /* Check if object is in memory */
2787 if (VALUE_LVAL (argp) != lval_memory)
2788 {
2789 warning (_("Couldn't retrieve complete object of RTTI type %s; object may be in register(s)."),
2790 TYPE_NAME (real_type));
2791
2792 return argp;
2793 }
2794
2795 /* All other cases -- retrieve the complete object. */
2796 /* Go back by the computed top_offset from the beginning of the
2797 object, adjusting for the embedded offset of argp if that's what
2798 value_rtti_type used for its computation. */
2799 new_val = value_at_lazy (real_type, VALUE_ADDRESS (argp) - top +
2800 (using_enc ? 0 : value_embedded_offset (argp)));
2801 deprecated_set_value_type (new_val, value_type (argp));
2802 set_value_embedded_offset (new_val, (using_enc
2803 ? top + value_embedded_offset (argp)
2804 : top));
2805 return new_val;
2806 }
2807
2808
2809 /* Return the value of the local variable, if one exists.
2810 Flag COMPLAIN signals an error if the request is made in an
2811 inappropriate context. */
2812
2813 struct value *
2814 value_of_local (const char *name, int complain)
2815 {
2816 struct symbol *func, *sym;
2817 struct block *b;
2818 struct value * ret;
2819 struct frame_info *frame;
2820
2821 if (complain)
2822 frame = get_selected_frame (_("no frame selected"));
2823 else
2824 {
2825 frame = deprecated_safe_get_selected_frame ();
2826 if (frame == 0)
2827 return 0;
2828 }
2829
2830 func = get_frame_function (frame);
2831 if (!func)
2832 {
2833 if (complain)
2834 error (_("no `%s' in nameless context"), name);
2835 else
2836 return 0;
2837 }
2838
2839 b = SYMBOL_BLOCK_VALUE (func);
2840 if (dict_empty (BLOCK_DICT (b)))
2841 {
2842 if (complain)
2843 error (_("no args, no `%s'"), name);
2844 else
2845 return 0;
2846 }
2847
2848 /* Calling lookup_block_symbol is necessary to get the LOC_REGISTER
2849 symbol instead of the LOC_ARG one (if both exist). */
2850 sym = lookup_block_symbol (b, name, NULL, VAR_DOMAIN);
2851 if (sym == NULL)
2852 {
2853 if (complain)
2854 error (_("current stack frame does not contain a variable named `%s'"),
2855 name);
2856 else
2857 return NULL;
2858 }
2859
2860 ret = read_var_value (sym, frame);
2861 if (ret == 0 && complain)
2862 error (_("`%s' argument unreadable"), name);
2863 return ret;
2864 }
2865
2866 /* C++/Objective-C: return the value of the class instance variable,
2867 if one exists. Flag COMPLAIN signals an error if the request is
2868 made in an inappropriate context. */
2869
2870 struct value *
2871 value_of_this (int complain)
2872 {
2873 if (!current_language->la_name_of_this)
2874 return 0;
2875 return value_of_local (current_language->la_name_of_this, complain);
2876 }
2877
2878 /* Create a slice (sub-string, sub-array) of ARRAY, that is LENGTH
2879 elements long, starting at LOWBOUND. The result has the same lower
2880 bound as the original ARRAY. */
2881
2882 struct value *
2883 value_slice (struct value *array, int lowbound, int length)
2884 {
2885 struct type *slice_range_type, *slice_type, *range_type;
2886 LONGEST lowerbound, upperbound;
2887 struct value *slice;
2888 struct type *array_type;
2889
2890 array_type = check_typedef (value_type (array));
2891 if (TYPE_CODE (array_type) != TYPE_CODE_ARRAY
2892 && TYPE_CODE (array_type) != TYPE_CODE_STRING
2893 && TYPE_CODE (array_type) != TYPE_CODE_BITSTRING)
2894 error (_("cannot take slice of non-array"));
2895
2896 range_type = TYPE_INDEX_TYPE (array_type);
2897 if (get_discrete_bounds (range_type, &lowerbound, &upperbound) < 0)
2898 error (_("slice from bad array or bitstring"));
2899
2900 if (lowbound < lowerbound || length < 0
2901 || lowbound + length - 1 > upperbound)
2902 error (_("slice out of range"));
2903
2904 /* FIXME-type-allocation: need a way to free this type when we are
2905 done with it. */
2906 slice_range_type = create_range_type ((struct type *) NULL,
2907 TYPE_TARGET_TYPE (range_type),
2908 lowbound,
2909 lowbound + length - 1);
2910 if (TYPE_CODE (array_type) == TYPE_CODE_BITSTRING)
2911 {
2912 int i;
2913
2914 slice_type = create_set_type ((struct type *) NULL,
2915 slice_range_type);
2916 TYPE_CODE (slice_type) = TYPE_CODE_BITSTRING;
2917 slice = value_zero (slice_type, not_lval);
2918
2919 for (i = 0; i < length; i++)
2920 {
2921 int element = value_bit_index (array_type,
2922 value_contents (array),
2923 lowbound + i);
2924 if (element < 0)
2925 error (_("internal error accessing bitstring"));
2926 else if (element > 0)
2927 {
2928 int j = i % TARGET_CHAR_BIT;
2929 if (gdbarch_bits_big_endian (current_gdbarch))
2930 j = TARGET_CHAR_BIT - 1 - j;
2931 value_contents_raw (slice)[i / TARGET_CHAR_BIT] |= (1 << j);
2932 }
2933 }
2934 /* We should set the address, bitssize, and bitspos, so the
2935 slice can be used on the LHS, but that may require extensions
2936 to value_assign. For now, just leave as a non_lval.
2937 FIXME. */
2938 }
2939 else
2940 {
2941 struct type *element_type = TYPE_TARGET_TYPE (array_type);
2942 LONGEST offset =
2943 (lowbound - lowerbound) * TYPE_LENGTH (check_typedef (element_type));
2944
2945 slice_type = create_array_type ((struct type *) NULL,
2946 element_type,
2947 slice_range_type);
2948 TYPE_CODE (slice_type) = TYPE_CODE (array_type);
2949
2950 slice = allocate_value (slice_type);
2951 if (VALUE_LVAL (array) == lval_memory && value_lazy (array))
2952 set_value_lazy (slice, 1);
2953 else
2954 memcpy (value_contents_writeable (slice),
2955 value_contents (array) + offset,
2956 TYPE_LENGTH (slice_type));
2957
2958 if (VALUE_LVAL (array) == lval_internalvar)
2959 VALUE_LVAL (slice) = lval_internalvar_component;
2960 else
2961 VALUE_LVAL (slice) = VALUE_LVAL (array);
2962
2963 VALUE_ADDRESS (slice) = VALUE_ADDRESS (array);
2964 VALUE_FRAME_ID (slice) = VALUE_FRAME_ID (array);
2965 set_value_offset (slice, value_offset (array) + offset);
2966 }
2967 return slice;
2968 }
2969
2970 /* Create a value for a FORTRAN complex number. Currently most of the
2971 time values are coerced to COMPLEX*16 (i.e. a complex number
2972 composed of 2 doubles. This really should be a smarter routine
2973 that figures out precision inteligently as opposed to assuming
2974 doubles. FIXME: fmb */
2975
2976 struct value *
2977 value_literal_complex (struct value *arg1,
2978 struct value *arg2,
2979 struct type *type)
2980 {
2981 struct value *val;
2982 struct type *real_type = TYPE_TARGET_TYPE (type);
2983
2984 val = allocate_value (type);
2985 arg1 = value_cast (real_type, arg1);
2986 arg2 = value_cast (real_type, arg2);
2987
2988 memcpy (value_contents_raw (val),
2989 value_contents (arg1), TYPE_LENGTH (real_type));
2990 memcpy (value_contents_raw (val) + TYPE_LENGTH (real_type),
2991 value_contents (arg2), TYPE_LENGTH (real_type));
2992 return val;
2993 }
2994
2995 /* Cast a value into the appropriate complex data type. */
2996
2997 static struct value *
2998 cast_into_complex (struct type *type, struct value *val)
2999 {
3000 struct type *real_type = TYPE_TARGET_TYPE (type);
3001
3002 if (TYPE_CODE (value_type (val)) == TYPE_CODE_COMPLEX)
3003 {
3004 struct type *val_real_type = TYPE_TARGET_TYPE (value_type (val));
3005 struct value *re_val = allocate_value (val_real_type);
3006 struct value *im_val = allocate_value (val_real_type);
3007
3008 memcpy (value_contents_raw (re_val),
3009 value_contents (val), TYPE_LENGTH (val_real_type));
3010 memcpy (value_contents_raw (im_val),
3011 value_contents (val) + TYPE_LENGTH (val_real_type),
3012 TYPE_LENGTH (val_real_type));
3013
3014 return value_literal_complex (re_val, im_val, type);
3015 }
3016 else if (TYPE_CODE (value_type (val)) == TYPE_CODE_FLT
3017 || TYPE_CODE (value_type (val)) == TYPE_CODE_INT)
3018 return value_literal_complex (val,
3019 value_zero (real_type, not_lval),
3020 type);
3021 else
3022 error (_("cannot cast non-number to complex"));
3023 }
3024
3025 void
3026 _initialize_valops (void)
3027 {
3028 add_setshow_boolean_cmd ("overload-resolution", class_support,
3029 &overload_resolution, _("\
3030 Set overload resolution in evaluating C++ functions."), _("\
3031 Show overload resolution in evaluating C++ functions."),
3032 NULL, NULL,
3033 show_overload_resolution,
3034 &setlist, &showlist);
3035 overload_resolution = 1;
3036 }
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