]> git.ipfire.org Git - thirdparty/binutils-gdb.git/blob - gdb/valops.c
Copyright updates for 2007.
[thirdparty/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 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 2 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, write to the Free Software
21 Foundation, Inc., 51 Franklin Street, Fifth Floor,
22 Boston, MA 02110-1301, USA. */
23
24 #include "defs.h"
25 #include "symtab.h"
26 #include "gdbtypes.h"
27 #include "value.h"
28 #include "frame.h"
29 #include "inferior.h"
30 #include "gdbcore.h"
31 #include "target.h"
32 #include "demangle.h"
33 #include "language.h"
34 #include "gdbcmd.h"
35 #include "regcache.h"
36 #include "cp-abi.h"
37 #include "block.h"
38 #include "infcall.h"
39 #include "dictionary.h"
40 #include "cp-support.h"
41
42 #include <errno.h>
43 #include "gdb_string.h"
44 #include "gdb_assert.h"
45 #include "cp-support.h"
46 #include "observer.h"
47
48 extern int overload_debug;
49 /* Local functions. */
50
51 static int typecmp (int staticp, int varargs, int nargs,
52 struct field t1[], struct value *t2[]);
53
54 static struct value *search_struct_field (char *, struct value *, int,
55 struct type *, int);
56
57 static struct value *search_struct_method (char *, struct value **,
58 struct value **,
59 int, int *, struct type *);
60
61 static int find_oload_champ_namespace (struct type **arg_types, int nargs,
62 const char *func_name,
63 const char *qualified_name,
64 struct symbol ***oload_syms,
65 struct badness_vector **oload_champ_bv);
66
67 static
68 int find_oload_champ_namespace_loop (struct type **arg_types, int nargs,
69 const char *func_name,
70 const char *qualified_name,
71 int namespace_len,
72 struct symbol ***oload_syms,
73 struct badness_vector **oload_champ_bv,
74 int *oload_champ);
75
76 static int find_oload_champ (struct type **arg_types, int nargs, int method,
77 int num_fns,
78 struct fn_field *fns_ptr,
79 struct symbol **oload_syms,
80 struct badness_vector **oload_champ_bv);
81
82 static int oload_method_static (int method, struct fn_field *fns_ptr,
83 int index);
84
85 enum oload_classification { STANDARD, NON_STANDARD, INCOMPATIBLE };
86
87 static enum
88 oload_classification classify_oload_match (struct badness_vector
89 * oload_champ_bv,
90 int nargs,
91 int static_offset);
92
93 static int check_field_in (struct type *, const char *);
94
95 static struct value *value_struct_elt_for_reference (struct type *domain,
96 int offset,
97 struct type *curtype,
98 char *name,
99 struct type *intype,
100 int want_address,
101 enum noside noside);
102
103 static struct value *value_namespace_elt (const struct type *curtype,
104 char *name, int want_address,
105 enum noside noside);
106
107 static struct value *value_maybe_namespace_elt (const struct type *curtype,
108 char *name, int want_address,
109 enum noside noside);
110
111 static CORE_ADDR allocate_space_in_inferior (int);
112
113 static struct value *cast_into_complex (struct type *, struct value *);
114
115 static struct fn_field *find_method_list (struct value ** argp, char *method,
116 int offset,
117 struct type *type, int *num_fns,
118 struct type **basetype,
119 int *boffset);
120
121 void _initialize_valops (void);
122
123 /* Flag for whether we want to abandon failed expression evals by default. */
124
125 #if 0
126 static int auto_abandon = 0;
127 #endif
128
129 int overload_resolution = 0;
130 static void
131 show_overload_resolution (struct ui_file *file, int from_tty,
132 struct cmd_list_element *c, const char *value)
133 {
134 fprintf_filtered (file, _("\
135 Overload resolution in evaluating C++ functions is %s.\n"),
136 value);
137 }
138
139 /* Find the address of function name NAME in the inferior. */
140
141 struct value *
142 find_function_in_inferior (const char *name)
143 {
144 struct symbol *sym;
145 sym = lookup_symbol (name, 0, VAR_DOMAIN, 0, NULL);
146 if (sym != NULL)
147 {
148 if (SYMBOL_CLASS (sym) != LOC_BLOCK)
149 {
150 error (_("\"%s\" exists in this program but is not a function."),
151 name);
152 }
153 return value_of_variable (sym, NULL);
154 }
155 else
156 {
157 struct minimal_symbol *msymbol = lookup_minimal_symbol (name, NULL, NULL);
158 if (msymbol != NULL)
159 {
160 struct type *type;
161 CORE_ADDR maddr;
162 type = lookup_pointer_type (builtin_type_char);
163 type = lookup_function_type (type);
164 type = lookup_pointer_type (type);
165 maddr = SYMBOL_VALUE_ADDRESS (msymbol);
166 return value_from_pointer (type, maddr);
167 }
168 else
169 {
170 if (!target_has_execution)
171 error (_("evaluation of this expression requires the target program to be active"));
172 else
173 error (_("evaluation of this expression requires the program to have a function \"%s\"."), name);
174 }
175 }
176 }
177
178 /* Allocate NBYTES of space in the inferior using the inferior's malloc
179 and return a value that is a pointer to the allocated space. */
180
181 struct value *
182 value_allocate_space_in_inferior (int len)
183 {
184 struct value *blocklen;
185 struct value *val = find_function_in_inferior (NAME_OF_MALLOC);
186
187 blocklen = value_from_longest (builtin_type_int, (LONGEST) len);
188 val = call_function_by_hand (val, 1, &blocklen);
189 if (value_logical_not (val))
190 {
191 if (!target_has_execution)
192 error (_("No memory available to program now: you need to start the target first"));
193 else
194 error (_("No memory available to program: call to malloc failed"));
195 }
196 return val;
197 }
198
199 static CORE_ADDR
200 allocate_space_in_inferior (int len)
201 {
202 return value_as_long (value_allocate_space_in_inferior (len));
203 }
204
205 /* Cast one pointer or reference type to another. Both TYPE and
206 the type of ARG2 should be pointer types, or else both should be
207 reference types. Returns the new pointer or reference. */
208
209 struct value *
210 value_cast_pointers (struct type *type, struct value *arg2)
211 {
212 struct type *type2 = check_typedef (value_type (arg2));
213 struct type *t1 = check_typedef (TYPE_TARGET_TYPE (type));
214 struct type *t2 = check_typedef (TYPE_TARGET_TYPE (type2));
215
216 if (TYPE_CODE (t1) == TYPE_CODE_STRUCT
217 && TYPE_CODE (t2) == TYPE_CODE_STRUCT
218 && !value_logical_not (arg2))
219 {
220 struct value *v;
221
222 /* Look in the type of the source to see if it contains the
223 type of the target as a superclass. If so, we'll need to
224 offset the pointer rather than just change its type. */
225 if (TYPE_NAME (t1) != NULL)
226 {
227 struct value *v2;
228
229 if (TYPE_CODE (type2) == TYPE_CODE_REF)
230 v2 = coerce_ref (arg2);
231 else
232 v2 = value_ind (arg2);
233 v = search_struct_field (type_name_no_tag (t1),
234 v2, 0, t2, 1);
235 if (v)
236 {
237 v = value_addr (v);
238 deprecated_set_value_type (v, type);
239 return v;
240 }
241 }
242
243 /* Look in the type of the target to see if it contains the
244 type of the source as a superclass. If so, we'll need to
245 offset the pointer rather than just change its type.
246 FIXME: This fails silently with virtual inheritance. */
247 if (TYPE_NAME (t2) != NULL)
248 {
249 v = search_struct_field (type_name_no_tag (t2),
250 value_zero (t1, not_lval), 0, t1, 1);
251 if (v)
252 {
253 CORE_ADDR addr2 = value_as_address (arg2);
254 addr2 -= (VALUE_ADDRESS (v)
255 + value_offset (v)
256 + value_embedded_offset (v));
257 return value_from_pointer (type, addr2);
258 }
259 }
260 }
261
262 /* No superclass found, just change the pointer type. */
263 arg2 = value_copy (arg2);
264 deprecated_set_value_type (arg2, type);
265 arg2 = value_change_enclosing_type (arg2, type);
266 set_value_pointed_to_offset (arg2, 0); /* pai: chk_val */
267 return arg2;
268 }
269
270 /* Cast value ARG2 to type TYPE and return as a value.
271 More general than a C cast: accepts any two types of the same length,
272 and if ARG2 is an lvalue it can be cast into anything at all. */
273 /* In C++, casts may change pointer or object representations. */
274
275 struct value *
276 value_cast (struct type *type, struct value *arg2)
277 {
278 enum type_code code1;
279 enum type_code code2;
280 int scalar;
281 struct type *type2;
282
283 int convert_to_boolean = 0;
284
285 if (value_type (arg2) == type)
286 return arg2;
287
288 CHECK_TYPEDEF (type);
289 code1 = TYPE_CODE (type);
290 arg2 = coerce_ref (arg2);
291 type2 = check_typedef (value_type (arg2));
292
293 /* You can't cast to a reference type. See value_cast_pointers
294 instead. */
295 gdb_assert (code1 != TYPE_CODE_REF);
296
297 /* A cast to an undetermined-length array_type, such as (TYPE [])OBJECT,
298 is treated like a cast to (TYPE [N])OBJECT,
299 where N is sizeof(OBJECT)/sizeof(TYPE). */
300 if (code1 == TYPE_CODE_ARRAY)
301 {
302 struct type *element_type = TYPE_TARGET_TYPE (type);
303 unsigned element_length = TYPE_LENGTH (check_typedef (element_type));
304 if (element_length > 0
305 && TYPE_ARRAY_UPPER_BOUND_TYPE (type) == BOUND_CANNOT_BE_DETERMINED)
306 {
307 struct type *range_type = TYPE_INDEX_TYPE (type);
308 int val_length = TYPE_LENGTH (type2);
309 LONGEST low_bound, high_bound, new_length;
310 if (get_discrete_bounds (range_type, &low_bound, &high_bound) < 0)
311 low_bound = 0, high_bound = 0;
312 new_length = val_length / element_length;
313 if (val_length % element_length != 0)
314 warning (_("array element type size does not divide object size in cast"));
315 /* FIXME-type-allocation: need a way to free this type when we are
316 done with it. */
317 range_type = create_range_type ((struct type *) NULL,
318 TYPE_TARGET_TYPE (range_type),
319 low_bound,
320 new_length + low_bound - 1);
321 deprecated_set_value_type (arg2, create_array_type ((struct type *) NULL,
322 element_type, range_type));
323 return arg2;
324 }
325 }
326
327 if (current_language->c_style_arrays
328 && TYPE_CODE (type2) == TYPE_CODE_ARRAY)
329 arg2 = value_coerce_array (arg2);
330
331 if (TYPE_CODE (type2) == TYPE_CODE_FUNC)
332 arg2 = value_coerce_function (arg2);
333
334 type2 = check_typedef (value_type (arg2));
335 code2 = TYPE_CODE (type2);
336
337 if (code1 == TYPE_CODE_COMPLEX)
338 return cast_into_complex (type, arg2);
339 if (code1 == TYPE_CODE_BOOL)
340 {
341 code1 = TYPE_CODE_INT;
342 convert_to_boolean = 1;
343 }
344 if (code1 == TYPE_CODE_CHAR)
345 code1 = TYPE_CODE_INT;
346 if (code2 == TYPE_CODE_BOOL || code2 == TYPE_CODE_CHAR)
347 code2 = TYPE_CODE_INT;
348
349 scalar = (code2 == TYPE_CODE_INT || code2 == TYPE_CODE_FLT
350 || code2 == TYPE_CODE_ENUM || code2 == TYPE_CODE_RANGE);
351
352 if (code1 == TYPE_CODE_STRUCT
353 && code2 == TYPE_CODE_STRUCT
354 && TYPE_NAME (type) != 0)
355 {
356 /* Look in the type of the source to see if it contains the
357 type of the target as a superclass. If so, we'll need to
358 offset the object in addition to changing its type. */
359 struct value *v = search_struct_field (type_name_no_tag (type),
360 arg2, 0, type2, 1);
361 if (v)
362 {
363 deprecated_set_value_type (v, type);
364 return v;
365 }
366 }
367 if (code1 == TYPE_CODE_FLT && scalar)
368 return value_from_double (type, value_as_double (arg2));
369 else if ((code1 == TYPE_CODE_INT || code1 == TYPE_CODE_ENUM
370 || code1 == TYPE_CODE_RANGE)
371 && (scalar || code2 == TYPE_CODE_PTR
372 || code2 == TYPE_CODE_MEMBERPTR))
373 {
374 LONGEST longest;
375
376 /* If target compiled by HP aCC. */
377 if (deprecated_hp_som_som_object_present
378 && code2 == TYPE_CODE_MEMBERPTR)
379 {
380 unsigned int *ptr;
381 struct value *retvalp;
382
383 /* With HP aCC, pointers to data members have a bias. */
384 retvalp = value_from_longest (type, value_as_long (arg2));
385 /* force evaluation */
386 ptr = (unsigned int *) value_contents (retvalp);
387 *ptr &= ~0x20000000; /* zap 29th bit to remove bias */
388 return retvalp;
389 }
390
391 /* When we cast pointers to integers, we mustn't use
392 POINTER_TO_ADDRESS to find the address the pointer
393 represents, as value_as_long would. GDB should evaluate
394 expressions just as the compiler would --- and the compiler
395 sees a cast as a simple reinterpretation of the pointer's
396 bits. */
397 if (code2 == TYPE_CODE_PTR)
398 longest = extract_unsigned_integer (value_contents (arg2),
399 TYPE_LENGTH (type2));
400 else
401 longest = value_as_long (arg2);
402 return value_from_longest (type, convert_to_boolean ?
403 (LONGEST) (longest ? 1 : 0) : longest);
404 }
405 else if (code1 == TYPE_CODE_PTR && (code2 == TYPE_CODE_INT ||
406 code2 == TYPE_CODE_ENUM ||
407 code2 == TYPE_CODE_RANGE))
408 {
409 /* TYPE_LENGTH (type) is the length of a pointer, but we really
410 want the length of an address! -- we are really dealing with
411 addresses (i.e., gdb representations) not pointers (i.e.,
412 target representations) here.
413
414 This allows things like "print *(int *)0x01000234" to work
415 without printing a misleading message -- which would
416 otherwise occur when dealing with a target having two byte
417 pointers and four byte addresses. */
418
419 int addr_bit = TARGET_ADDR_BIT;
420
421 LONGEST longest = value_as_long (arg2);
422 if (addr_bit < sizeof (LONGEST) * HOST_CHAR_BIT)
423 {
424 if (longest >= ((LONGEST) 1 << addr_bit)
425 || longest <= -((LONGEST) 1 << addr_bit))
426 warning (_("value truncated"));
427 }
428 return value_from_longest (type, longest);
429 }
430 else if (code1 == TYPE_CODE_METHODPTR && code2 == TYPE_CODE_INT
431 && value_as_long (arg2) == 0)
432 {
433 struct value *result = allocate_value (type);
434 cplus_make_method_ptr (value_contents_writeable (result), 0, 0);
435 return result;
436 }
437 else if (code1 == TYPE_CODE_MEMBERPTR && code2 == TYPE_CODE_INT
438 && value_as_long (arg2) == 0)
439 {
440 /* The Itanium C++ ABI represents NULL pointers to members as
441 minus one, instead of biasing the normal case. */
442 return value_from_longest (type, -1);
443 }
444 else if (TYPE_LENGTH (type) == TYPE_LENGTH (type2))
445 {
446 if (code1 == TYPE_CODE_PTR && code2 == TYPE_CODE_PTR)
447 return value_cast_pointers (type, arg2);
448
449 arg2 = value_copy (arg2);
450 deprecated_set_value_type (arg2, type);
451 arg2 = value_change_enclosing_type (arg2, type);
452 set_value_pointed_to_offset (arg2, 0); /* pai: chk_val */
453 return arg2;
454 }
455 else if (VALUE_LVAL (arg2) == lval_memory)
456 return value_at_lazy (type, VALUE_ADDRESS (arg2) + value_offset (arg2));
457 else if (code1 == TYPE_CODE_VOID)
458 {
459 return value_zero (builtin_type_void, not_lval);
460 }
461 else
462 {
463 error (_("Invalid cast."));
464 return 0;
465 }
466 }
467
468 /* Create a value of type TYPE that is zero, and return it. */
469
470 struct value *
471 value_zero (struct type *type, enum lval_type lv)
472 {
473 struct value *val = allocate_value (type);
474 VALUE_LVAL (val) = lv;
475
476 return val;
477 }
478
479 /* Return a value with type TYPE located at ADDR.
480
481 Call value_at only if the data needs to be fetched immediately;
482 if we can be 'lazy' and defer the fetch, perhaps indefinately, call
483 value_at_lazy instead. value_at_lazy simply records the address of
484 the data and sets the lazy-evaluation-required flag. The lazy flag
485 is tested in the value_contents macro, which is used if and when
486 the contents are actually required.
487
488 Note: value_at does *NOT* handle embedded offsets; perform such
489 adjustments before or after calling it. */
490
491 struct value *
492 value_at (struct type *type, CORE_ADDR addr)
493 {
494 struct value *val;
495
496 if (TYPE_CODE (check_typedef (type)) == TYPE_CODE_VOID)
497 error (_("Attempt to dereference a generic pointer."));
498
499 val = allocate_value (type);
500
501 read_memory (addr, value_contents_all_raw (val), TYPE_LENGTH (type));
502
503 VALUE_LVAL (val) = lval_memory;
504 VALUE_ADDRESS (val) = addr;
505
506 return val;
507 }
508
509 /* Return a lazy value with type TYPE located at ADDR (cf. value_at). */
510
511 struct value *
512 value_at_lazy (struct type *type, CORE_ADDR addr)
513 {
514 struct value *val;
515
516 if (TYPE_CODE (check_typedef (type)) == TYPE_CODE_VOID)
517 error (_("Attempt to dereference a generic pointer."));
518
519 val = allocate_value (type);
520
521 VALUE_LVAL (val) = lval_memory;
522 VALUE_ADDRESS (val) = addr;
523 set_value_lazy (val, 1);
524
525 return val;
526 }
527
528 /* Called only from the value_contents and value_contents_all()
529 macros, if the current data for a variable needs to be loaded into
530 value_contents(VAL). Fetches the data from the user's process, and
531 clears the lazy flag to indicate that the data in the buffer is
532 valid.
533
534 If the value is zero-length, we avoid calling read_memory, which would
535 abort. We mark the value as fetched anyway -- all 0 bytes of it.
536
537 This function returns a value because it is used in the value_contents
538 macro as part of an expression, where a void would not work. The
539 value is ignored. */
540
541 int
542 value_fetch_lazy (struct value *val)
543 {
544 CORE_ADDR addr = VALUE_ADDRESS (val) + value_offset (val);
545 int length = TYPE_LENGTH (value_enclosing_type (val));
546
547 struct type *type = value_type (val);
548 if (length)
549 read_memory (addr, value_contents_all_raw (val), length);
550
551 set_value_lazy (val, 0);
552 return 0;
553 }
554
555
556 /* Store the contents of FROMVAL into the location of TOVAL.
557 Return a new value with the location of TOVAL and contents of FROMVAL. */
558
559 struct value *
560 value_assign (struct value *toval, struct value *fromval)
561 {
562 struct type *type;
563 struct value *val;
564 struct frame_id old_frame;
565
566 if (!deprecated_value_modifiable (toval))
567 error (_("Left operand of assignment is not a modifiable lvalue."));
568
569 toval = coerce_ref (toval);
570
571 type = value_type (toval);
572 if (VALUE_LVAL (toval) != lval_internalvar)
573 fromval = value_cast (type, fromval);
574 else
575 fromval = coerce_array (fromval);
576 CHECK_TYPEDEF (type);
577
578 /* Since modifying a register can trash the frame chain, and modifying memory
579 can trash the frame cache, we save the old frame and then restore the new
580 frame afterwards. */
581 old_frame = get_frame_id (deprecated_selected_frame);
582
583 switch (VALUE_LVAL (toval))
584 {
585 case lval_internalvar:
586 set_internalvar (VALUE_INTERNALVAR (toval), fromval);
587 val = value_copy (VALUE_INTERNALVAR (toval)->value);
588 val = value_change_enclosing_type (val, value_enclosing_type (fromval));
589 set_value_embedded_offset (val, value_embedded_offset (fromval));
590 set_value_pointed_to_offset (val, value_pointed_to_offset (fromval));
591 return val;
592
593 case lval_internalvar_component:
594 set_internalvar_component (VALUE_INTERNALVAR (toval),
595 value_offset (toval),
596 value_bitpos (toval),
597 value_bitsize (toval),
598 fromval);
599 break;
600
601 case lval_memory:
602 {
603 const gdb_byte *dest_buffer;
604 CORE_ADDR changed_addr;
605 int changed_len;
606 gdb_byte buffer[sizeof (LONGEST)];
607
608 if (value_bitsize (toval))
609 {
610 /* We assume that the argument to read_memory is in units of
611 host chars. FIXME: Is that correct? */
612 changed_len = (value_bitpos (toval)
613 + value_bitsize (toval)
614 + HOST_CHAR_BIT - 1)
615 / HOST_CHAR_BIT;
616
617 if (changed_len > (int) sizeof (LONGEST))
618 error (_("Can't handle bitfields which don't fit in a %d bit word."),
619 (int) sizeof (LONGEST) * HOST_CHAR_BIT);
620
621 read_memory (VALUE_ADDRESS (toval) + value_offset (toval),
622 buffer, changed_len);
623 modify_field (buffer, value_as_long (fromval),
624 value_bitpos (toval), value_bitsize (toval));
625 changed_addr = VALUE_ADDRESS (toval) + value_offset (toval);
626 dest_buffer = buffer;
627 }
628 else
629 {
630 changed_addr = VALUE_ADDRESS (toval) + value_offset (toval);
631 changed_len = TYPE_LENGTH (type);
632 dest_buffer = value_contents (fromval);
633 }
634
635 write_memory (changed_addr, dest_buffer, changed_len);
636 if (deprecated_memory_changed_hook)
637 deprecated_memory_changed_hook (changed_addr, changed_len);
638 }
639 break;
640
641 case lval_register:
642 {
643 struct frame_info *frame;
644 int value_reg;
645
646 /* Figure out which frame this is in currently. */
647 frame = frame_find_by_id (VALUE_FRAME_ID (toval));
648 value_reg = VALUE_REGNUM (toval);
649
650 if (!frame)
651 error (_("Value being assigned to is no longer active."));
652
653 if (CONVERT_REGISTER_P (VALUE_REGNUM (toval), type))
654 {
655 /* If TOVAL is a special machine register requiring
656 conversion of program values to a special raw format. */
657 VALUE_TO_REGISTER (frame, VALUE_REGNUM (toval),
658 type, value_contents (fromval));
659 }
660 else
661 {
662 if (value_bitsize (toval))
663 {
664 int changed_len;
665 gdb_byte buffer[sizeof (LONGEST)];
666
667 changed_len = (value_bitpos (toval)
668 + value_bitsize (toval)
669 + HOST_CHAR_BIT - 1)
670 / HOST_CHAR_BIT;
671
672 if (changed_len > (int) sizeof (LONGEST))
673 error (_("Can't handle bitfields which don't fit in a %d bit word."),
674 (int) sizeof (LONGEST) * HOST_CHAR_BIT);
675
676 get_frame_register_bytes (frame, value_reg,
677 value_offset (toval),
678 changed_len, buffer);
679
680 modify_field (buffer, value_as_long (fromval),
681 value_bitpos (toval), value_bitsize (toval));
682
683 put_frame_register_bytes (frame, value_reg,
684 value_offset (toval),
685 changed_len, buffer);
686 }
687 else
688 {
689 put_frame_register_bytes (frame, value_reg,
690 value_offset (toval),
691 TYPE_LENGTH (type),
692 value_contents (fromval));
693 }
694 }
695
696 if (deprecated_register_changed_hook)
697 deprecated_register_changed_hook (-1);
698 observer_notify_target_changed (&current_target);
699 break;
700 }
701
702 default:
703 error (_("Left operand of assignment is not an lvalue."));
704 }
705
706 /* Assigning to the stack pointer, frame pointer, and other
707 (architecture and calling convention specific) registers may
708 cause the frame cache to be out of date. Assigning to memory
709 also can. We just do this on all assignments to registers or
710 memory, for simplicity's sake; I doubt the slowdown matters. */
711 switch (VALUE_LVAL (toval))
712 {
713 case lval_memory:
714 case lval_register:
715
716 reinit_frame_cache ();
717
718 /* Having destoroyed the frame cache, restore the selected frame. */
719
720 /* FIXME: cagney/2002-11-02: There has to be a better way of
721 doing this. Instead of constantly saving/restoring the
722 frame. Why not create a get_selected_frame() function that,
723 having saved the selected frame's ID can automatically
724 re-find the previously selected frame automatically. */
725
726 {
727 struct frame_info *fi = frame_find_by_id (old_frame);
728 if (fi != NULL)
729 select_frame (fi);
730 }
731
732 break;
733 default:
734 break;
735 }
736
737 /* If the field does not entirely fill a LONGEST, then zero the sign bits.
738 If the field is signed, and is negative, then sign extend. */
739 if ((value_bitsize (toval) > 0)
740 && (value_bitsize (toval) < 8 * (int) sizeof (LONGEST)))
741 {
742 LONGEST fieldval = value_as_long (fromval);
743 LONGEST valmask = (((ULONGEST) 1) << value_bitsize (toval)) - 1;
744
745 fieldval &= valmask;
746 if (!TYPE_UNSIGNED (type) && (fieldval & (valmask ^ (valmask >> 1))))
747 fieldval |= ~valmask;
748
749 fromval = value_from_longest (type, fieldval);
750 }
751
752 val = value_copy (toval);
753 memcpy (value_contents_raw (val), value_contents (fromval),
754 TYPE_LENGTH (type));
755 deprecated_set_value_type (val, type);
756 val = value_change_enclosing_type (val, value_enclosing_type (fromval));
757 set_value_embedded_offset (val, value_embedded_offset (fromval));
758 set_value_pointed_to_offset (val, value_pointed_to_offset (fromval));
759
760 return val;
761 }
762
763 /* Extend a value VAL to COUNT repetitions of its type. */
764
765 struct value *
766 value_repeat (struct value *arg1, int count)
767 {
768 struct value *val;
769
770 if (VALUE_LVAL (arg1) != lval_memory)
771 error (_("Only values in memory can be extended with '@'."));
772 if (count < 1)
773 error (_("Invalid number %d of repetitions."), count);
774
775 val = allocate_repeat_value (value_enclosing_type (arg1), count);
776
777 read_memory (VALUE_ADDRESS (arg1) + value_offset (arg1),
778 value_contents_all_raw (val),
779 TYPE_LENGTH (value_enclosing_type (val)));
780 VALUE_LVAL (val) = lval_memory;
781 VALUE_ADDRESS (val) = VALUE_ADDRESS (arg1) + value_offset (arg1);
782
783 return val;
784 }
785
786 struct value *
787 value_of_variable (struct symbol *var, struct block *b)
788 {
789 struct value *val;
790 struct frame_info *frame = NULL;
791
792 if (!b)
793 frame = NULL; /* Use selected frame. */
794 else if (symbol_read_needs_frame (var))
795 {
796 frame = block_innermost_frame (b);
797 if (!frame)
798 {
799 if (BLOCK_FUNCTION (b)
800 && SYMBOL_PRINT_NAME (BLOCK_FUNCTION (b)))
801 error (_("No frame is currently executing in block %s."),
802 SYMBOL_PRINT_NAME (BLOCK_FUNCTION (b)));
803 else
804 error (_("No frame is currently executing in specified block"));
805 }
806 }
807
808 val = read_var_value (var, frame);
809 if (!val)
810 error (_("Address of symbol \"%s\" is unknown."), SYMBOL_PRINT_NAME (var));
811
812 return val;
813 }
814
815 /* Given a value which is an array, return a value which is a pointer to its
816 first element, regardless of whether or not the array has a nonzero lower
817 bound.
818
819 FIXME: A previous comment here indicated that this routine should be
820 substracting the array's lower bound. It's not clear to me that this
821 is correct. Given an array subscripting operation, it would certainly
822 work to do the adjustment here, essentially computing:
823
824 (&array[0] - (lowerbound * sizeof array[0])) + (index * sizeof array[0])
825
826 However I believe a more appropriate and logical place to account for
827 the lower bound is to do so in value_subscript, essentially computing:
828
829 (&array[0] + ((index - lowerbound) * sizeof array[0]))
830
831 As further evidence consider what would happen with operations other
832 than array subscripting, where the caller would get back a value that
833 had an address somewhere before the actual first element of the array,
834 and the information about the lower bound would be lost because of
835 the coercion to pointer type.
836 */
837
838 struct value *
839 value_coerce_array (struct value *arg1)
840 {
841 struct type *type = check_typedef (value_type (arg1));
842
843 if (VALUE_LVAL (arg1) != lval_memory)
844 error (_("Attempt to take address of value not located in memory."));
845
846 return value_from_pointer (lookup_pointer_type (TYPE_TARGET_TYPE (type)),
847 (VALUE_ADDRESS (arg1) + value_offset (arg1)));
848 }
849
850 /* Given a value which is a function, return a value which is a pointer
851 to it. */
852
853 struct value *
854 value_coerce_function (struct value *arg1)
855 {
856 struct value *retval;
857
858 if (VALUE_LVAL (arg1) != lval_memory)
859 error (_("Attempt to take address of value not located in memory."));
860
861 retval = value_from_pointer (lookup_pointer_type (value_type (arg1)),
862 (VALUE_ADDRESS (arg1) + value_offset (arg1)));
863 return retval;
864 }
865
866 /* Return a pointer value for the object for which ARG1 is the contents. */
867
868 struct value *
869 value_addr (struct value *arg1)
870 {
871 struct value *arg2;
872
873 struct type *type = check_typedef (value_type (arg1));
874 if (TYPE_CODE (type) == TYPE_CODE_REF)
875 {
876 /* Copy the value, but change the type from (T&) to (T*).
877 We keep the same location information, which is efficient,
878 and allows &(&X) to get the location containing the reference. */
879 arg2 = value_copy (arg1);
880 deprecated_set_value_type (arg2, lookup_pointer_type (TYPE_TARGET_TYPE (type)));
881 return arg2;
882 }
883 if (TYPE_CODE (type) == TYPE_CODE_FUNC)
884 return value_coerce_function (arg1);
885
886 if (VALUE_LVAL (arg1) != lval_memory)
887 error (_("Attempt to take address of value not located in memory."));
888
889 /* Get target memory address */
890 arg2 = value_from_pointer (lookup_pointer_type (value_type (arg1)),
891 (VALUE_ADDRESS (arg1)
892 + value_offset (arg1)
893 + value_embedded_offset (arg1)));
894
895 /* This may be a pointer to a base subobject; so remember the
896 full derived object's type ... */
897 arg2 = value_change_enclosing_type (arg2, lookup_pointer_type (value_enclosing_type (arg1)));
898 /* ... and also the relative position of the subobject in the full object */
899 set_value_pointed_to_offset (arg2, value_embedded_offset (arg1));
900 return arg2;
901 }
902
903 /* Return a reference value for the object for which ARG1 is the contents. */
904
905 struct value *
906 value_ref (struct value *arg1)
907 {
908 struct value *arg2;
909
910 struct type *type = check_typedef (value_type (arg1));
911 if (TYPE_CODE (type) == TYPE_CODE_REF)
912 return arg1;
913
914 arg2 = value_addr (arg1);
915 deprecated_set_value_type (arg2, lookup_reference_type (type));
916 return arg2;
917 }
918
919 /* Given a value of a pointer type, apply the C unary * operator to it. */
920
921 struct value *
922 value_ind (struct value *arg1)
923 {
924 struct type *base_type;
925 struct value *arg2;
926
927 arg1 = coerce_array (arg1);
928
929 base_type = check_typedef (value_type (arg1));
930
931 /* Allow * on an integer so we can cast it to whatever we want.
932 This returns an int, which seems like the most C-like thing
933 to do. "long long" variables are rare enough that
934 BUILTIN_TYPE_LONGEST would seem to be a mistake. */
935 if (TYPE_CODE (base_type) == TYPE_CODE_INT)
936 return value_at_lazy (builtin_type_int,
937 (CORE_ADDR) value_as_long (arg1));
938 else if (TYPE_CODE (base_type) == TYPE_CODE_PTR)
939 {
940 struct type *enc_type;
941 /* We may be pointing to something embedded in a larger object */
942 /* Get the real type of the enclosing object */
943 enc_type = check_typedef (value_enclosing_type (arg1));
944 enc_type = TYPE_TARGET_TYPE (enc_type);
945
946 if (TYPE_CODE (check_typedef (enc_type)) == TYPE_CODE_FUNC
947 || TYPE_CODE (check_typedef (enc_type)) == TYPE_CODE_METHOD)
948 /* For functions, go through find_function_addr, which knows
949 how to handle function descriptors. */
950 arg2 = value_at_lazy (enc_type, find_function_addr (arg1, NULL));
951 else
952 /* Retrieve the enclosing object pointed to */
953 arg2 = value_at_lazy (enc_type, (value_as_address (arg1)
954 - value_pointed_to_offset (arg1)));
955
956 /* Re-adjust type */
957 deprecated_set_value_type (arg2, TYPE_TARGET_TYPE (base_type));
958 /* Add embedding info */
959 arg2 = value_change_enclosing_type (arg2, enc_type);
960 set_value_embedded_offset (arg2, value_pointed_to_offset (arg1));
961
962 /* We may be pointing to an object of some derived type */
963 arg2 = value_full_object (arg2, NULL, 0, 0, 0);
964 return arg2;
965 }
966
967 error (_("Attempt to take contents of a non-pointer value."));
968 return 0; /* For lint -- never reached */
969 }
970 \f
971 /* Create a value for an array by allocating space in the inferior, copying
972 the data into that space, and then setting up an array value.
973
974 The array bounds are set from LOWBOUND and HIGHBOUND, and the array is
975 populated from the values passed in ELEMVEC.
976
977 The element type of the array is inherited from the type of the
978 first element, and all elements must have the same size (though we
979 don't currently enforce any restriction on their types). */
980
981 struct value *
982 value_array (int lowbound, int highbound, struct value **elemvec)
983 {
984 int nelem;
985 int idx;
986 unsigned int typelength;
987 struct value *val;
988 struct type *rangetype;
989 struct type *arraytype;
990 CORE_ADDR addr;
991
992 /* Validate that the bounds are reasonable and that each of the elements
993 have the same size. */
994
995 nelem = highbound - lowbound + 1;
996 if (nelem <= 0)
997 {
998 error (_("bad array bounds (%d, %d)"), lowbound, highbound);
999 }
1000 typelength = TYPE_LENGTH (value_enclosing_type (elemvec[0]));
1001 for (idx = 1; idx < nelem; idx++)
1002 {
1003 if (TYPE_LENGTH (value_enclosing_type (elemvec[idx])) != typelength)
1004 {
1005 error (_("array elements must all be the same size"));
1006 }
1007 }
1008
1009 rangetype = create_range_type ((struct type *) NULL, builtin_type_int,
1010 lowbound, highbound);
1011 arraytype = create_array_type ((struct type *) NULL,
1012 value_enclosing_type (elemvec[0]), rangetype);
1013
1014 if (!current_language->c_style_arrays)
1015 {
1016 val = allocate_value (arraytype);
1017 for (idx = 0; idx < nelem; idx++)
1018 {
1019 memcpy (value_contents_all_raw (val) + (idx * typelength),
1020 value_contents_all (elemvec[idx]),
1021 typelength);
1022 }
1023 return val;
1024 }
1025
1026 /* Allocate space to store the array in the inferior, and then initialize
1027 it by copying in each element. FIXME: Is it worth it to create a
1028 local buffer in which to collect each value and then write all the
1029 bytes in one operation? */
1030
1031 addr = allocate_space_in_inferior (nelem * typelength);
1032 for (idx = 0; idx < nelem; idx++)
1033 {
1034 write_memory (addr + (idx * typelength),
1035 value_contents_all (elemvec[idx]),
1036 typelength);
1037 }
1038
1039 /* Create the array type and set up an array value to be evaluated lazily. */
1040
1041 val = value_at_lazy (arraytype, addr);
1042 return (val);
1043 }
1044
1045 /* Create a value for a string constant by allocating space in the inferior,
1046 copying the data into that space, and returning the address with type
1047 TYPE_CODE_STRING. PTR points to the string constant data; LEN is number
1048 of characters.
1049 Note that string types are like array of char types with a lower bound of
1050 zero and an upper bound of LEN - 1. Also note that the string may contain
1051 embedded null bytes. */
1052
1053 struct value *
1054 value_string (char *ptr, int len)
1055 {
1056 struct value *val;
1057 int lowbound = current_language->string_lower_bound;
1058 struct type *rangetype = create_range_type ((struct type *) NULL,
1059 builtin_type_int,
1060 lowbound, len + lowbound - 1);
1061 struct type *stringtype
1062 = create_string_type ((struct type *) NULL, rangetype);
1063 CORE_ADDR addr;
1064
1065 if (current_language->c_style_arrays == 0)
1066 {
1067 val = allocate_value (stringtype);
1068 memcpy (value_contents_raw (val), ptr, len);
1069 return val;
1070 }
1071
1072
1073 /* Allocate space to store the string in the inferior, and then
1074 copy LEN bytes from PTR in gdb to that address in the inferior. */
1075
1076 addr = allocate_space_in_inferior (len);
1077 write_memory (addr, (gdb_byte *) ptr, len);
1078
1079 val = value_at_lazy (stringtype, addr);
1080 return (val);
1081 }
1082
1083 struct value *
1084 value_bitstring (char *ptr, int len)
1085 {
1086 struct value *val;
1087 struct type *domain_type = create_range_type (NULL, builtin_type_int,
1088 0, len - 1);
1089 struct type *type = create_set_type ((struct type *) NULL, domain_type);
1090 TYPE_CODE (type) = TYPE_CODE_BITSTRING;
1091 val = allocate_value (type);
1092 memcpy (value_contents_raw (val), ptr, TYPE_LENGTH (type));
1093 return val;
1094 }
1095 \f
1096 /* See if we can pass arguments in T2 to a function which takes arguments
1097 of types T1. T1 is a list of NARGS arguments, and T2 is a NULL-terminated
1098 vector. If some arguments need coercion of some sort, then the coerced
1099 values are written into T2. Return value is 0 if the arguments could be
1100 matched, or the position at which they differ if not.
1101
1102 STATICP is nonzero if the T1 argument list came from a
1103 static member function. T2 will still include the ``this'' pointer,
1104 but it will be skipped.
1105
1106 For non-static member functions, we ignore the first argument,
1107 which is the type of the instance variable. This is because we want
1108 to handle calls with objects from derived classes. This is not
1109 entirely correct: we should actually check to make sure that a
1110 requested operation is type secure, shouldn't we? FIXME. */
1111
1112 static int
1113 typecmp (int staticp, int varargs, int nargs,
1114 struct field t1[], struct value *t2[])
1115 {
1116 int i;
1117
1118 if (t2 == 0)
1119 internal_error (__FILE__, __LINE__, _("typecmp: no argument list"));
1120
1121 /* Skip ``this'' argument if applicable. T2 will always include THIS. */
1122 if (staticp)
1123 t2 ++;
1124
1125 for (i = 0;
1126 (i < nargs) && TYPE_CODE (t1[i].type) != TYPE_CODE_VOID;
1127 i++)
1128 {
1129 struct type *tt1, *tt2;
1130
1131 if (!t2[i])
1132 return i + 1;
1133
1134 tt1 = check_typedef (t1[i].type);
1135 tt2 = check_typedef (value_type (t2[i]));
1136
1137 if (TYPE_CODE (tt1) == TYPE_CODE_REF
1138 /* We should be doing hairy argument matching, as below. */
1139 && (TYPE_CODE (check_typedef (TYPE_TARGET_TYPE (tt1))) == TYPE_CODE (tt2)))
1140 {
1141 if (TYPE_CODE (tt2) == TYPE_CODE_ARRAY)
1142 t2[i] = value_coerce_array (t2[i]);
1143 else
1144 t2[i] = value_ref (t2[i]);
1145 continue;
1146 }
1147
1148 /* djb - 20000715 - Until the new type structure is in the
1149 place, and we can attempt things like implicit conversions,
1150 we need to do this so you can take something like a map<const
1151 char *>, and properly access map["hello"], because the
1152 argument to [] will be a reference to a pointer to a char,
1153 and the argument will be a pointer to a char. */
1154 while ( TYPE_CODE(tt1) == TYPE_CODE_REF ||
1155 TYPE_CODE (tt1) == TYPE_CODE_PTR)
1156 {
1157 tt1 = check_typedef( TYPE_TARGET_TYPE(tt1) );
1158 }
1159 while ( TYPE_CODE(tt2) == TYPE_CODE_ARRAY ||
1160 TYPE_CODE(tt2) == TYPE_CODE_PTR ||
1161 TYPE_CODE(tt2) == TYPE_CODE_REF)
1162 {
1163 tt2 = check_typedef( TYPE_TARGET_TYPE(tt2) );
1164 }
1165 if (TYPE_CODE (tt1) == TYPE_CODE (tt2))
1166 continue;
1167 /* Array to pointer is a `trivial conversion' according to the ARM. */
1168
1169 /* We should be doing much hairier argument matching (see section 13.2
1170 of the ARM), but as a quick kludge, just check for the same type
1171 code. */
1172 if (TYPE_CODE (t1[i].type) != TYPE_CODE (value_type (t2[i])))
1173 return i + 1;
1174 }
1175 if (varargs || t2[i] == NULL)
1176 return 0;
1177 return i + 1;
1178 }
1179
1180 /* Helper function used by value_struct_elt to recurse through baseclasses.
1181 Look for a field NAME in ARG1. Adjust the address of ARG1 by OFFSET bytes,
1182 and search in it assuming it has (class) type TYPE.
1183 If found, return value, else return NULL.
1184
1185 If LOOKING_FOR_BASECLASS, then instead of looking for struct fields,
1186 look for a baseclass named NAME. */
1187
1188 static struct value *
1189 search_struct_field (char *name, struct value *arg1, int offset,
1190 struct type *type, int looking_for_baseclass)
1191 {
1192 int i;
1193 int nbases = TYPE_N_BASECLASSES (type);
1194
1195 CHECK_TYPEDEF (type);
1196
1197 if (!looking_for_baseclass)
1198 for (i = TYPE_NFIELDS (type) - 1; i >= nbases; i--)
1199 {
1200 char *t_field_name = TYPE_FIELD_NAME (type, i);
1201
1202 if (t_field_name && (strcmp_iw (t_field_name, name) == 0))
1203 {
1204 struct value *v;
1205 if (TYPE_FIELD_STATIC (type, i))
1206 {
1207 v = value_static_field (type, i);
1208 if (v == 0)
1209 error (_("field %s is nonexistent or has been optimised out"),
1210 name);
1211 }
1212 else
1213 {
1214 v = value_primitive_field (arg1, offset, i, type);
1215 if (v == 0)
1216 error (_("there is no field named %s"), name);
1217 }
1218 return v;
1219 }
1220
1221 if (t_field_name
1222 && (t_field_name[0] == '\0'
1223 || (TYPE_CODE (type) == TYPE_CODE_UNION
1224 && (strcmp_iw (t_field_name, "else") == 0))))
1225 {
1226 struct type *field_type = TYPE_FIELD_TYPE (type, i);
1227 if (TYPE_CODE (field_type) == TYPE_CODE_UNION
1228 || TYPE_CODE (field_type) == TYPE_CODE_STRUCT)
1229 {
1230 /* Look for a match through the fields of an anonymous union,
1231 or anonymous struct. C++ provides anonymous unions.
1232
1233 In the GNU Chill (now deleted from GDB)
1234 implementation of variant record types, each
1235 <alternative field> has an (anonymous) union type,
1236 each member of the union represents a <variant
1237 alternative>. Each <variant alternative> is
1238 represented as a struct, with a member for each
1239 <variant field>. */
1240
1241 struct value *v;
1242 int new_offset = offset;
1243
1244 /* This is pretty gross. In G++, the offset in an
1245 anonymous union is relative to the beginning of the
1246 enclosing struct. In the GNU Chill (now deleted
1247 from GDB) implementation of variant records, the
1248 bitpos is zero in an anonymous union field, so we
1249 have to add the offset of the union here. */
1250 if (TYPE_CODE (field_type) == TYPE_CODE_STRUCT
1251 || (TYPE_NFIELDS (field_type) > 0
1252 && TYPE_FIELD_BITPOS (field_type, 0) == 0))
1253 new_offset += TYPE_FIELD_BITPOS (type, i) / 8;
1254
1255 v = search_struct_field (name, arg1, new_offset, field_type,
1256 looking_for_baseclass);
1257 if (v)
1258 return v;
1259 }
1260 }
1261 }
1262
1263 for (i = 0; i < nbases; i++)
1264 {
1265 struct value *v;
1266 struct type *basetype = check_typedef (TYPE_BASECLASS (type, i));
1267 /* If we are looking for baseclasses, this is what we get when we
1268 hit them. But it could happen that the base part's member name
1269 is not yet filled in. */
1270 int found_baseclass = (looking_for_baseclass
1271 && TYPE_BASECLASS_NAME (type, i) != NULL
1272 && (strcmp_iw (name, TYPE_BASECLASS_NAME (type, i)) == 0));
1273
1274 if (BASETYPE_VIA_VIRTUAL (type, i))
1275 {
1276 int boffset;
1277 struct value *v2 = allocate_value (basetype);
1278
1279 boffset = baseclass_offset (type, i,
1280 value_contents (arg1) + offset,
1281 VALUE_ADDRESS (arg1)
1282 + value_offset (arg1) + offset);
1283 if (boffset == -1)
1284 error (_("virtual baseclass botch"));
1285
1286 /* The virtual base class pointer might have been clobbered by the
1287 user program. Make sure that it still points to a valid memory
1288 location. */
1289
1290 boffset += offset;
1291 if (boffset < 0 || boffset >= TYPE_LENGTH (type))
1292 {
1293 CORE_ADDR base_addr;
1294
1295 base_addr = VALUE_ADDRESS (arg1) + value_offset (arg1) + boffset;
1296 if (target_read_memory (base_addr, value_contents_raw (v2),
1297 TYPE_LENGTH (basetype)) != 0)
1298 error (_("virtual baseclass botch"));
1299 VALUE_LVAL (v2) = lval_memory;
1300 VALUE_ADDRESS (v2) = base_addr;
1301 }
1302 else
1303 {
1304 VALUE_LVAL (v2) = VALUE_LVAL (arg1);
1305 VALUE_ADDRESS (v2) = VALUE_ADDRESS (arg1);
1306 VALUE_FRAME_ID (v2) = VALUE_FRAME_ID (arg1);
1307 set_value_offset (v2, value_offset (arg1) + boffset);
1308 if (value_lazy (arg1))
1309 set_value_lazy (v2, 1);
1310 else
1311 memcpy (value_contents_raw (v2),
1312 value_contents_raw (arg1) + boffset,
1313 TYPE_LENGTH (basetype));
1314 }
1315
1316 if (found_baseclass)
1317 return v2;
1318 v = search_struct_field (name, v2, 0, TYPE_BASECLASS (type, i),
1319 looking_for_baseclass);
1320 }
1321 else if (found_baseclass)
1322 v = value_primitive_field (arg1, offset, i, type);
1323 else
1324 v = search_struct_field (name, arg1,
1325 offset + TYPE_BASECLASS_BITPOS (type, i) / 8,
1326 basetype, looking_for_baseclass);
1327 if (v)
1328 return v;
1329 }
1330 return NULL;
1331 }
1332
1333
1334 /* Return the offset (in bytes) of the virtual base of type BASETYPE
1335 * in an object pointed to by VALADDR (on the host), assumed to be of
1336 * type TYPE. OFFSET is number of bytes beyond start of ARG to start
1337 * looking (in case VALADDR is the contents of an enclosing object).
1338 *
1339 * This routine recurses on the primary base of the derived class because
1340 * the virtual base entries of the primary base appear before the other
1341 * virtual base entries.
1342 *
1343 * If the virtual base is not found, a negative integer is returned.
1344 * The magnitude of the negative integer is the number of entries in
1345 * the virtual table to skip over (entries corresponding to various
1346 * ancestral classes in the chain of primary bases).
1347 *
1348 * Important: This assumes the HP / Taligent C++ runtime
1349 * conventions. Use baseclass_offset() instead to deal with g++
1350 * conventions. */
1351
1352 void
1353 find_rt_vbase_offset (struct type *type, struct type *basetype,
1354 const gdb_byte *valaddr, int offset, int *boffset_p,
1355 int *skip_p)
1356 {
1357 int boffset; /* offset of virtual base */
1358 int index; /* displacement to use in virtual table */
1359 int skip;
1360
1361 struct value *vp;
1362 CORE_ADDR vtbl; /* the virtual table pointer */
1363 struct type *pbc; /* the primary base class */
1364
1365 /* Look for the virtual base recursively in the primary base, first.
1366 * This is because the derived class object and its primary base
1367 * subobject share the primary virtual table. */
1368
1369 boffset = 0;
1370 pbc = TYPE_PRIMARY_BASE (type);
1371 if (pbc)
1372 {
1373 find_rt_vbase_offset (pbc, basetype, valaddr, offset, &boffset, &skip);
1374 if (skip < 0)
1375 {
1376 *boffset_p = boffset;
1377 *skip_p = -1;
1378 return;
1379 }
1380 }
1381 else
1382 skip = 0;
1383
1384
1385 /* Find the index of the virtual base according to HP/Taligent
1386 runtime spec. (Depth-first, left-to-right.) */
1387 index = virtual_base_index_skip_primaries (basetype, type);
1388
1389 if (index < 0)
1390 {
1391 *skip_p = skip + virtual_base_list_length_skip_primaries (type);
1392 *boffset_p = 0;
1393 return;
1394 }
1395
1396 /* pai: FIXME -- 32x64 possible problem */
1397 /* First word (4 bytes) in object layout is the vtable pointer */
1398 vtbl = *(CORE_ADDR *) (valaddr + offset);
1399
1400 /* Before the constructor is invoked, things are usually zero'd out. */
1401 if (vtbl == 0)
1402 error (_("Couldn't find virtual table -- object may not be constructed yet."));
1403
1404
1405 /* Find virtual base's offset -- jump over entries for primary base
1406 * ancestors, then use the index computed above. But also adjust by
1407 * HP_ACC_VBASE_START for the vtable slots before the start of the
1408 * virtual base entries. Offset is negative -- virtual base entries
1409 * appear _before_ the address point of the virtual table. */
1410
1411 /* pai: FIXME -- 32x64 problem, if word = 8 bytes, change multiplier
1412 & use long type */
1413
1414 /* epstein : FIXME -- added param for overlay section. May not be correct */
1415 vp = value_at (builtin_type_int, vtbl + 4 * (-skip - index - HP_ACC_VBASE_START));
1416 boffset = value_as_long (vp);
1417 *skip_p = -1;
1418 *boffset_p = boffset;
1419 return;
1420 }
1421
1422
1423 /* Helper function used by value_struct_elt to recurse through baseclasses.
1424 Look for a field NAME in ARG1. Adjust the address of ARG1 by OFFSET bytes,
1425 and search in it assuming it has (class) type TYPE.
1426 If found, return value, else if name matched and args not return (value)-1,
1427 else return NULL. */
1428
1429 static struct value *
1430 search_struct_method (char *name, struct value **arg1p,
1431 struct value **args, int offset,
1432 int *static_memfuncp, struct type *type)
1433 {
1434 int i;
1435 struct value *v;
1436 int name_matched = 0;
1437 char dem_opname[64];
1438
1439 CHECK_TYPEDEF (type);
1440 for (i = TYPE_NFN_FIELDS (type) - 1; i >= 0; i--)
1441 {
1442 char *t_field_name = TYPE_FN_FIELDLIST_NAME (type, i);
1443 /* FIXME! May need to check for ARM demangling here */
1444 if (strncmp (t_field_name, "__", 2) == 0 ||
1445 strncmp (t_field_name, "op", 2) == 0 ||
1446 strncmp (t_field_name, "type", 4) == 0)
1447 {
1448 if (cplus_demangle_opname (t_field_name, dem_opname, DMGL_ANSI))
1449 t_field_name = dem_opname;
1450 else if (cplus_demangle_opname (t_field_name, dem_opname, 0))
1451 t_field_name = dem_opname;
1452 }
1453 if (t_field_name && (strcmp_iw (t_field_name, name) == 0))
1454 {
1455 int j = TYPE_FN_FIELDLIST_LENGTH (type, i) - 1;
1456 struct fn_field *f = TYPE_FN_FIELDLIST1 (type, i);
1457 name_matched = 1;
1458
1459 check_stub_method_group (type, i);
1460 if (j > 0 && args == 0)
1461 error (_("cannot resolve overloaded method `%s': no arguments supplied"), name);
1462 else if (j == 0 && args == 0)
1463 {
1464 v = value_fn_field (arg1p, f, j, type, offset);
1465 if (v != NULL)
1466 return v;
1467 }
1468 else
1469 while (j >= 0)
1470 {
1471 if (!typecmp (TYPE_FN_FIELD_STATIC_P (f, j),
1472 TYPE_VARARGS (TYPE_FN_FIELD_TYPE (f, j)),
1473 TYPE_NFIELDS (TYPE_FN_FIELD_TYPE (f, j)),
1474 TYPE_FN_FIELD_ARGS (f, j), args))
1475 {
1476 if (TYPE_FN_FIELD_VIRTUAL_P (f, j))
1477 return value_virtual_fn_field (arg1p, f, j, type, offset);
1478 if (TYPE_FN_FIELD_STATIC_P (f, j) && static_memfuncp)
1479 *static_memfuncp = 1;
1480 v = value_fn_field (arg1p, f, j, type, offset);
1481 if (v != NULL)
1482 return v;
1483 }
1484 j--;
1485 }
1486 }
1487 }
1488
1489 for (i = TYPE_N_BASECLASSES (type) - 1; i >= 0; i--)
1490 {
1491 int base_offset;
1492
1493 if (BASETYPE_VIA_VIRTUAL (type, i))
1494 {
1495 if (TYPE_HAS_VTABLE (type))
1496 {
1497 /* HP aCC compiled type, search for virtual base offset
1498 according to HP/Taligent runtime spec. */
1499 int skip;
1500 find_rt_vbase_offset (type, TYPE_BASECLASS (type, i),
1501 value_contents_all (*arg1p),
1502 offset + value_embedded_offset (*arg1p),
1503 &base_offset, &skip);
1504 if (skip >= 0)
1505 error (_("Virtual base class offset not found in vtable"));
1506 }
1507 else
1508 {
1509 struct type *baseclass = check_typedef (TYPE_BASECLASS (type, i));
1510 const gdb_byte *base_valaddr;
1511
1512 /* The virtual base class pointer might have been clobbered by the
1513 user program. Make sure that it still points to a valid memory
1514 location. */
1515
1516 if (offset < 0 || offset >= TYPE_LENGTH (type))
1517 {
1518 gdb_byte *tmp = alloca (TYPE_LENGTH (baseclass));
1519 if (target_read_memory (VALUE_ADDRESS (*arg1p)
1520 + value_offset (*arg1p) + offset,
1521 tmp, TYPE_LENGTH (baseclass)) != 0)
1522 error (_("virtual baseclass botch"));
1523 base_valaddr = tmp;
1524 }
1525 else
1526 base_valaddr = value_contents (*arg1p) + offset;
1527
1528 base_offset =
1529 baseclass_offset (type, i, base_valaddr,
1530 VALUE_ADDRESS (*arg1p)
1531 + value_offset (*arg1p) + offset);
1532 if (base_offset == -1)
1533 error (_("virtual baseclass botch"));
1534 }
1535 }
1536 else
1537 {
1538 base_offset = TYPE_BASECLASS_BITPOS (type, i) / 8;
1539 }
1540 v = search_struct_method (name, arg1p, args, base_offset + offset,
1541 static_memfuncp, TYPE_BASECLASS (type, i));
1542 if (v == (struct value *) - 1)
1543 {
1544 name_matched = 1;
1545 }
1546 else if (v)
1547 {
1548 /* FIXME-bothner: Why is this commented out? Why is it here? */
1549 /* *arg1p = arg1_tmp; */
1550 return v;
1551 }
1552 }
1553 if (name_matched)
1554 return (struct value *) - 1;
1555 else
1556 return NULL;
1557 }
1558
1559 /* Given *ARGP, a value of type (pointer to a)* structure/union,
1560 extract the component named NAME from the ultimate target structure/union
1561 and return it as a value with its appropriate type.
1562 ERR is used in the error message if *ARGP's type is wrong.
1563
1564 C++: ARGS is a list of argument types to aid in the selection of
1565 an appropriate method. Also, handle derived types.
1566
1567 STATIC_MEMFUNCP, if non-NULL, points to a caller-supplied location
1568 where the truthvalue of whether the function that was resolved was
1569 a static member function or not is stored.
1570
1571 ERR is an error message to be printed in case the field is not found. */
1572
1573 struct value *
1574 value_struct_elt (struct value **argp, struct value **args,
1575 char *name, int *static_memfuncp, char *err)
1576 {
1577 struct type *t;
1578 struct value *v;
1579
1580 *argp = coerce_array (*argp);
1581
1582 t = check_typedef (value_type (*argp));
1583
1584 /* Follow pointers until we get to a non-pointer. */
1585
1586 while (TYPE_CODE (t) == TYPE_CODE_PTR || TYPE_CODE (t) == TYPE_CODE_REF)
1587 {
1588 *argp = value_ind (*argp);
1589 /* Don't coerce fn pointer to fn and then back again! */
1590 if (TYPE_CODE (value_type (*argp)) != TYPE_CODE_FUNC)
1591 *argp = coerce_array (*argp);
1592 t = check_typedef (value_type (*argp));
1593 }
1594
1595 if (TYPE_CODE (t) != TYPE_CODE_STRUCT
1596 && TYPE_CODE (t) != TYPE_CODE_UNION)
1597 error (_("Attempt to extract a component of a value that is not a %s."), err);
1598
1599 /* Assume it's not, unless we see that it is. */
1600 if (static_memfuncp)
1601 *static_memfuncp = 0;
1602
1603 if (!args)
1604 {
1605 /* if there are no arguments ...do this... */
1606
1607 /* Try as a field first, because if we succeed, there
1608 is less work to be done. */
1609 v = search_struct_field (name, *argp, 0, t, 0);
1610 if (v)
1611 return v;
1612
1613 /* C++: If it was not found as a data field, then try to
1614 return it as a pointer to a method. */
1615
1616 if (destructor_name_p (name, t))
1617 error (_("Cannot get value of destructor"));
1618
1619 v = search_struct_method (name, argp, args, 0, static_memfuncp, t);
1620
1621 if (v == (struct value *) - 1)
1622 error (_("Cannot take address of method %s."), name);
1623 else if (v == 0)
1624 {
1625 if (TYPE_NFN_FIELDS (t))
1626 error (_("There is no member or method named %s."), name);
1627 else
1628 error (_("There is no member named %s."), name);
1629 }
1630 return v;
1631 }
1632
1633 if (destructor_name_p (name, t))
1634 {
1635 if (!args[1])
1636 {
1637 /* Destructors are a special case. */
1638 int m_index, f_index;
1639
1640 v = NULL;
1641 if (get_destructor_fn_field (t, &m_index, &f_index))
1642 {
1643 v = value_fn_field (NULL, TYPE_FN_FIELDLIST1 (t, m_index),
1644 f_index, NULL, 0);
1645 }
1646 if (v == NULL)
1647 error (_("could not find destructor function named %s."), name);
1648 else
1649 return v;
1650 }
1651 else
1652 {
1653 error (_("destructor should not have any argument"));
1654 }
1655 }
1656 else
1657 v = search_struct_method (name, argp, args, 0, static_memfuncp, t);
1658
1659 if (v == (struct value *) - 1)
1660 {
1661 error (_("One of the arguments you tried to pass to %s could not be converted to what the function wants."), name);
1662 }
1663 else if (v == 0)
1664 {
1665 /* See if user tried to invoke data as function. If so,
1666 hand it back. If it's not callable (i.e., a pointer to function),
1667 gdb should give an error. */
1668 v = search_struct_field (name, *argp, 0, t, 0);
1669 }
1670
1671 if (!v)
1672 error (_("Structure has no component named %s."), name);
1673 return v;
1674 }
1675
1676 /* Search through the methods of an object (and its bases)
1677 * to find a specified method. Return the pointer to the
1678 * fn_field list of overloaded instances.
1679 * Helper function for value_find_oload_list.
1680 * ARGP is a pointer to a pointer to a value (the object)
1681 * METHOD is a string containing the method name
1682 * OFFSET is the offset within the value
1683 * TYPE is the assumed type of the object
1684 * NUM_FNS is the number of overloaded instances
1685 * BASETYPE is set to the actual type of the subobject where the method is found
1686 * BOFFSET is the offset of the base subobject where the method is found */
1687
1688 static struct fn_field *
1689 find_method_list (struct value **argp, char *method, int offset,
1690 struct type *type, int *num_fns,
1691 struct type **basetype, int *boffset)
1692 {
1693 int i;
1694 struct fn_field *f;
1695 CHECK_TYPEDEF (type);
1696
1697 *num_fns = 0;
1698
1699 /* First check in object itself */
1700 for (i = TYPE_NFN_FIELDS (type) - 1; i >= 0; i--)
1701 {
1702 /* pai: FIXME What about operators and type conversions? */
1703 char *fn_field_name = TYPE_FN_FIELDLIST_NAME (type, i);
1704 if (fn_field_name && (strcmp_iw (fn_field_name, method) == 0))
1705 {
1706 int len = TYPE_FN_FIELDLIST_LENGTH (type, i);
1707 struct fn_field *f = TYPE_FN_FIELDLIST1 (type, i);
1708
1709 *num_fns = len;
1710 *basetype = type;
1711 *boffset = offset;
1712
1713 /* Resolve any stub methods. */
1714 check_stub_method_group (type, i);
1715
1716 return f;
1717 }
1718 }
1719
1720 /* Not found in object, check in base subobjects */
1721 for (i = TYPE_N_BASECLASSES (type) - 1; i >= 0; i--)
1722 {
1723 int base_offset;
1724 if (BASETYPE_VIA_VIRTUAL (type, i))
1725 {
1726 if (TYPE_HAS_VTABLE (type))
1727 {
1728 /* HP aCC compiled type, search for virtual base offset
1729 * according to HP/Taligent runtime spec. */
1730 int skip;
1731 find_rt_vbase_offset (type, TYPE_BASECLASS (type, i),
1732 value_contents_all (*argp),
1733 offset + value_embedded_offset (*argp),
1734 &base_offset, &skip);
1735 if (skip >= 0)
1736 error (_("Virtual base class offset not found in vtable"));
1737 }
1738 else
1739 {
1740 /* probably g++ runtime model */
1741 base_offset = value_offset (*argp) + offset;
1742 base_offset =
1743 baseclass_offset (type, i,
1744 value_contents (*argp) + base_offset,
1745 VALUE_ADDRESS (*argp) + base_offset);
1746 if (base_offset == -1)
1747 error (_("virtual baseclass botch"));
1748 }
1749 }
1750 else
1751 /* non-virtual base, simply use bit position from debug info */
1752 {
1753 base_offset = TYPE_BASECLASS_BITPOS (type, i) / 8;
1754 }
1755 f = find_method_list (argp, method, base_offset + offset,
1756 TYPE_BASECLASS (type, i), num_fns, basetype,
1757 boffset);
1758 if (f)
1759 return f;
1760 }
1761 return NULL;
1762 }
1763
1764 /* Return the list of overloaded methods of a specified name.
1765 * ARGP is a pointer to a pointer to a value (the object)
1766 * METHOD is the method name
1767 * OFFSET is the offset within the value contents
1768 * NUM_FNS is the number of overloaded instances
1769 * BASETYPE is set to the type of the base subobject that defines the method
1770 * BOFFSET is the offset of the base subobject which defines the method */
1771
1772 struct fn_field *
1773 value_find_oload_method_list (struct value **argp, char *method, int offset,
1774 int *num_fns, struct type **basetype,
1775 int *boffset)
1776 {
1777 struct type *t;
1778
1779 t = check_typedef (value_type (*argp));
1780
1781 /* code snarfed from value_struct_elt */
1782 while (TYPE_CODE (t) == TYPE_CODE_PTR || TYPE_CODE (t) == TYPE_CODE_REF)
1783 {
1784 *argp = value_ind (*argp);
1785 /* Don't coerce fn pointer to fn and then back again! */
1786 if (TYPE_CODE (value_type (*argp)) != TYPE_CODE_FUNC)
1787 *argp = coerce_array (*argp);
1788 t = check_typedef (value_type (*argp));
1789 }
1790
1791 if (TYPE_CODE (t) != TYPE_CODE_STRUCT
1792 && TYPE_CODE (t) != TYPE_CODE_UNION)
1793 error (_("Attempt to extract a component of a value that is not a struct or union"));
1794
1795 return find_method_list (argp, method, 0, t, num_fns, basetype, boffset);
1796 }
1797
1798 /* Given an array of argument types (ARGTYPES) (which includes an
1799 entry for "this" in the case of C++ methods), the number of
1800 arguments NARGS, the NAME of a function whether it's a method or
1801 not (METHOD), and the degree of laxness (LAX) in conforming to
1802 overload resolution rules in ANSI C++, find the best function that
1803 matches on the argument types according to the overload resolution
1804 rules.
1805
1806 In the case of class methods, the parameter OBJ is an object value
1807 in which to search for overloaded methods.
1808
1809 In the case of non-method functions, the parameter FSYM is a symbol
1810 corresponding to one of the overloaded functions.
1811
1812 Return value is an integer: 0 -> good match, 10 -> debugger applied
1813 non-standard coercions, 100 -> incompatible.
1814
1815 If a method is being searched for, VALP will hold the value.
1816 If a non-method is being searched for, SYMP will hold the symbol for it.
1817
1818 If a method is being searched for, and it is a static method,
1819 then STATICP will point to a non-zero value.
1820
1821 Note: This function does *not* check the value of
1822 overload_resolution. Caller must check it to see whether overload
1823 resolution is permitted.
1824 */
1825
1826 int
1827 find_overload_match (struct type **arg_types, int nargs, char *name, int method,
1828 int lax, struct value **objp, struct symbol *fsym,
1829 struct value **valp, struct symbol **symp, int *staticp)
1830 {
1831 struct value *obj = (objp ? *objp : NULL);
1832
1833 int oload_champ; /* Index of best overloaded function */
1834
1835 struct badness_vector *oload_champ_bv = NULL; /* The measure for the current best match */
1836
1837 struct value *temp = obj;
1838 struct fn_field *fns_ptr = NULL; /* For methods, the list of overloaded methods */
1839 struct symbol **oload_syms = NULL; /* For non-methods, the list of overloaded function symbols */
1840 int num_fns = 0; /* Number of overloaded instances being considered */
1841 struct type *basetype = NULL;
1842 int boffset;
1843 int ix;
1844 int static_offset;
1845 struct cleanup *old_cleanups = NULL;
1846
1847 const char *obj_type_name = NULL;
1848 char *func_name = NULL;
1849 enum oload_classification match_quality;
1850
1851 /* Get the list of overloaded methods or functions */
1852 if (method)
1853 {
1854 obj_type_name = TYPE_NAME (value_type (obj));
1855 /* Hack: evaluate_subexp_standard often passes in a pointer
1856 value rather than the object itself, so try again */
1857 if ((!obj_type_name || !*obj_type_name) &&
1858 (TYPE_CODE (value_type (obj)) == TYPE_CODE_PTR))
1859 obj_type_name = TYPE_NAME (TYPE_TARGET_TYPE (value_type (obj)));
1860
1861 fns_ptr = value_find_oload_method_list (&temp, name, 0,
1862 &num_fns,
1863 &basetype, &boffset);
1864 if (!fns_ptr || !num_fns)
1865 error (_("Couldn't find method %s%s%s"),
1866 obj_type_name,
1867 (obj_type_name && *obj_type_name) ? "::" : "",
1868 name);
1869 /* If we are dealing with stub method types, they should have
1870 been resolved by find_method_list via value_find_oload_method_list
1871 above. */
1872 gdb_assert (TYPE_DOMAIN_TYPE (fns_ptr[0].type) != NULL);
1873 oload_champ = find_oload_champ (arg_types, nargs, method, num_fns,
1874 fns_ptr, oload_syms, &oload_champ_bv);
1875 }
1876 else
1877 {
1878 const char *qualified_name = SYMBOL_CPLUS_DEMANGLED_NAME (fsym);
1879
1880 /* If we have a C++ name, try to extract just the function
1881 part. */
1882 if (qualified_name)
1883 func_name = cp_func_name (qualified_name);
1884
1885 /* If there was no C++ name, this must be a C-style function.
1886 Just return the same symbol. Do the same if cp_func_name
1887 fails for some reason. */
1888 if (func_name == NULL)
1889 {
1890 *symp = fsym;
1891 return 0;
1892 }
1893
1894 old_cleanups = make_cleanup (xfree, func_name);
1895 make_cleanup (xfree, oload_syms);
1896 make_cleanup (xfree, oload_champ_bv);
1897
1898 oload_champ = find_oload_champ_namespace (arg_types, nargs,
1899 func_name,
1900 qualified_name,
1901 &oload_syms,
1902 &oload_champ_bv);
1903 }
1904
1905 /* Check how bad the best match is. */
1906
1907 match_quality
1908 = classify_oload_match (oload_champ_bv, nargs,
1909 oload_method_static (method, fns_ptr,
1910 oload_champ));
1911
1912 if (match_quality == INCOMPATIBLE)
1913 {
1914 if (method)
1915 error (_("Cannot resolve method %s%s%s to any overloaded instance"),
1916 obj_type_name,
1917 (obj_type_name && *obj_type_name) ? "::" : "",
1918 name);
1919 else
1920 error (_("Cannot resolve function %s to any overloaded instance"),
1921 func_name);
1922 }
1923 else if (match_quality == NON_STANDARD)
1924 {
1925 if (method)
1926 warning (_("Using non-standard conversion to match method %s%s%s to supplied arguments"),
1927 obj_type_name,
1928 (obj_type_name && *obj_type_name) ? "::" : "",
1929 name);
1930 else
1931 warning (_("Using non-standard conversion to match function %s to supplied arguments"),
1932 func_name);
1933 }
1934
1935 if (method)
1936 {
1937 if (staticp != NULL)
1938 *staticp = oload_method_static (method, fns_ptr, oload_champ);
1939 if (TYPE_FN_FIELD_VIRTUAL_P (fns_ptr, oload_champ))
1940 *valp = value_virtual_fn_field (&temp, fns_ptr, oload_champ, basetype, boffset);
1941 else
1942 *valp = value_fn_field (&temp, fns_ptr, oload_champ, basetype, boffset);
1943 }
1944 else
1945 {
1946 *symp = oload_syms[oload_champ];
1947 }
1948
1949 if (objp)
1950 {
1951 if (TYPE_CODE (value_type (temp)) != TYPE_CODE_PTR
1952 && TYPE_CODE (value_type (*objp)) == TYPE_CODE_PTR)
1953 {
1954 temp = value_addr (temp);
1955 }
1956 *objp = temp;
1957 }
1958 if (old_cleanups != NULL)
1959 do_cleanups (old_cleanups);
1960
1961 switch (match_quality)
1962 {
1963 case INCOMPATIBLE:
1964 return 100;
1965 case NON_STANDARD:
1966 return 10;
1967 default: /* STANDARD */
1968 return 0;
1969 }
1970 }
1971
1972 /* Find the best overload match, searching for FUNC_NAME in namespaces
1973 contained in QUALIFIED_NAME until it either finds a good match or
1974 runs out of namespaces. It stores the overloaded functions in
1975 *OLOAD_SYMS, and the badness vector in *OLOAD_CHAMP_BV. The
1976 calling function is responsible for freeing *OLOAD_SYMS and
1977 *OLOAD_CHAMP_BV. */
1978
1979 static int
1980 find_oload_champ_namespace (struct type **arg_types, int nargs,
1981 const char *func_name,
1982 const char *qualified_name,
1983 struct symbol ***oload_syms,
1984 struct badness_vector **oload_champ_bv)
1985 {
1986 int oload_champ;
1987
1988 find_oload_champ_namespace_loop (arg_types, nargs,
1989 func_name,
1990 qualified_name, 0,
1991 oload_syms, oload_champ_bv,
1992 &oload_champ);
1993
1994 return oload_champ;
1995 }
1996
1997 /* Helper function for find_oload_champ_namespace; NAMESPACE_LEN is
1998 how deep we've looked for namespaces, and the champ is stored in
1999 OLOAD_CHAMP. The return value is 1 if the champ is a good one, 0
2000 if it isn't.
2001
2002 It is the caller's responsibility to free *OLOAD_SYMS and
2003 *OLOAD_CHAMP_BV. */
2004
2005 static int
2006 find_oload_champ_namespace_loop (struct type **arg_types, int nargs,
2007 const char *func_name,
2008 const char *qualified_name,
2009 int namespace_len,
2010 struct symbol ***oload_syms,
2011 struct badness_vector **oload_champ_bv,
2012 int *oload_champ)
2013 {
2014 int next_namespace_len = namespace_len;
2015 int searched_deeper = 0;
2016 int num_fns = 0;
2017 struct cleanup *old_cleanups;
2018 int new_oload_champ;
2019 struct symbol **new_oload_syms;
2020 struct badness_vector *new_oload_champ_bv;
2021 char *new_namespace;
2022
2023 if (next_namespace_len != 0)
2024 {
2025 gdb_assert (qualified_name[next_namespace_len] == ':');
2026 next_namespace_len += 2;
2027 }
2028 next_namespace_len
2029 += cp_find_first_component (qualified_name + next_namespace_len);
2030
2031 /* Initialize these to values that can safely be xfree'd. */
2032 *oload_syms = NULL;
2033 *oload_champ_bv = NULL;
2034
2035 /* First, see if we have a deeper namespace we can search in. If we
2036 get a good match there, use it. */
2037
2038 if (qualified_name[next_namespace_len] == ':')
2039 {
2040 searched_deeper = 1;
2041
2042 if (find_oload_champ_namespace_loop (arg_types, nargs,
2043 func_name, qualified_name,
2044 next_namespace_len,
2045 oload_syms, oload_champ_bv,
2046 oload_champ))
2047 {
2048 return 1;
2049 }
2050 };
2051
2052 /* If we reach here, either we're in the deepest namespace or we
2053 didn't find a good match in a deeper namespace. But, in the
2054 latter case, we still have a bad match in a deeper namespace;
2055 note that we might not find any match at all in the current
2056 namespace. (There's always a match in the deepest namespace,
2057 because this overload mechanism only gets called if there's a
2058 function symbol to start off with.) */
2059
2060 old_cleanups = make_cleanup (xfree, *oload_syms);
2061 old_cleanups = make_cleanup (xfree, *oload_champ_bv);
2062 new_namespace = alloca (namespace_len + 1);
2063 strncpy (new_namespace, qualified_name, namespace_len);
2064 new_namespace[namespace_len] = '\0';
2065 new_oload_syms = make_symbol_overload_list (func_name,
2066 new_namespace);
2067 while (new_oload_syms[num_fns])
2068 ++num_fns;
2069
2070 new_oload_champ = find_oload_champ (arg_types, nargs, 0, num_fns,
2071 NULL, new_oload_syms,
2072 &new_oload_champ_bv);
2073
2074 /* Case 1: We found a good match. Free earlier matches (if any),
2075 and return it. Case 2: We didn't find a good match, but we're
2076 not the deepest function. Then go with the bad match that the
2077 deeper function found. Case 3: We found a bad match, and we're
2078 the deepest function. Then return what we found, even though
2079 it's a bad match. */
2080
2081 if (new_oload_champ != -1
2082 && classify_oload_match (new_oload_champ_bv, nargs, 0) == STANDARD)
2083 {
2084 *oload_syms = new_oload_syms;
2085 *oload_champ = new_oload_champ;
2086 *oload_champ_bv = new_oload_champ_bv;
2087 do_cleanups (old_cleanups);
2088 return 1;
2089 }
2090 else if (searched_deeper)
2091 {
2092 xfree (new_oload_syms);
2093 xfree (new_oload_champ_bv);
2094 discard_cleanups (old_cleanups);
2095 return 0;
2096 }
2097 else
2098 {
2099 gdb_assert (new_oload_champ != -1);
2100 *oload_syms = new_oload_syms;
2101 *oload_champ = new_oload_champ;
2102 *oload_champ_bv = new_oload_champ_bv;
2103 discard_cleanups (old_cleanups);
2104 return 0;
2105 }
2106 }
2107
2108 /* Look for a function to take NARGS args of types ARG_TYPES. Find
2109 the best match from among the overloaded methods or functions
2110 (depending on METHOD) given by FNS_PTR or OLOAD_SYMS, respectively.
2111 The number of methods/functions in the list is given by NUM_FNS.
2112 Return the index of the best match; store an indication of the
2113 quality of the match in OLOAD_CHAMP_BV.
2114
2115 It is the caller's responsibility to free *OLOAD_CHAMP_BV. */
2116
2117 static int
2118 find_oload_champ (struct type **arg_types, int nargs, int method,
2119 int num_fns, struct fn_field *fns_ptr,
2120 struct symbol **oload_syms,
2121 struct badness_vector **oload_champ_bv)
2122 {
2123 int ix;
2124 struct badness_vector *bv; /* A measure of how good an overloaded instance is */
2125 int oload_champ = -1; /* Index of best overloaded function */
2126 int oload_ambiguous = 0; /* Current ambiguity state for overload resolution */
2127 /* 0 => no ambiguity, 1 => two good funcs, 2 => incomparable funcs */
2128
2129 *oload_champ_bv = NULL;
2130
2131 /* Consider each candidate in turn */
2132 for (ix = 0; ix < num_fns; ix++)
2133 {
2134 int jj;
2135 int static_offset = oload_method_static (method, fns_ptr, ix);
2136 int nparms;
2137 struct type **parm_types;
2138
2139 if (method)
2140 {
2141 nparms = TYPE_NFIELDS (TYPE_FN_FIELD_TYPE (fns_ptr, ix));
2142 }
2143 else
2144 {
2145 /* If it's not a method, this is the proper place */
2146 nparms=TYPE_NFIELDS(SYMBOL_TYPE(oload_syms[ix]));
2147 }
2148
2149 /* Prepare array of parameter types */
2150 parm_types = (struct type **) xmalloc (nparms * (sizeof (struct type *)));
2151 for (jj = 0; jj < nparms; jj++)
2152 parm_types[jj] = (method
2153 ? (TYPE_FN_FIELD_ARGS (fns_ptr, ix)[jj].type)
2154 : TYPE_FIELD_TYPE (SYMBOL_TYPE (oload_syms[ix]), jj));
2155
2156 /* Compare parameter types to supplied argument types. Skip THIS for
2157 static methods. */
2158 bv = rank_function (parm_types, nparms, arg_types + static_offset,
2159 nargs - static_offset);
2160
2161 if (!*oload_champ_bv)
2162 {
2163 *oload_champ_bv = bv;
2164 oload_champ = 0;
2165 }
2166 else
2167 /* See whether current candidate is better or worse than previous best */
2168 switch (compare_badness (bv, *oload_champ_bv))
2169 {
2170 case 0:
2171 oload_ambiguous = 1; /* top two contenders are equally good */
2172 break;
2173 case 1:
2174 oload_ambiguous = 2; /* incomparable top contenders */
2175 break;
2176 case 2:
2177 *oload_champ_bv = bv; /* new champion, record details */
2178 oload_ambiguous = 0;
2179 oload_champ = ix;
2180 break;
2181 case 3:
2182 default:
2183 break;
2184 }
2185 xfree (parm_types);
2186 if (overload_debug)
2187 {
2188 if (method)
2189 fprintf_filtered (gdb_stderr,"Overloaded method instance %s, # of parms %d\n", fns_ptr[ix].physname, nparms);
2190 else
2191 fprintf_filtered (gdb_stderr,"Overloaded function instance %s # of parms %d\n", SYMBOL_DEMANGLED_NAME (oload_syms[ix]), nparms);
2192 for (jj = 0; jj < nargs - static_offset; jj++)
2193 fprintf_filtered (gdb_stderr,"...Badness @ %d : %d\n", jj, bv->rank[jj]);
2194 fprintf_filtered (gdb_stderr,"Overload resolution champion is %d, ambiguous? %d\n", oload_champ, oload_ambiguous);
2195 }
2196 }
2197
2198 return oload_champ;
2199 }
2200
2201 /* Return 1 if we're looking at a static method, 0 if we're looking at
2202 a non-static method or a function that isn't a method. */
2203
2204 static int
2205 oload_method_static (int method, struct fn_field *fns_ptr, int index)
2206 {
2207 if (method && TYPE_FN_FIELD_STATIC_P (fns_ptr, index))
2208 return 1;
2209 else
2210 return 0;
2211 }
2212
2213 /* Check how good an overload match OLOAD_CHAMP_BV represents. */
2214
2215 static enum oload_classification
2216 classify_oload_match (struct badness_vector *oload_champ_bv,
2217 int nargs,
2218 int static_offset)
2219 {
2220 int ix;
2221
2222 for (ix = 1; ix <= nargs - static_offset; ix++)
2223 {
2224 if (oload_champ_bv->rank[ix] >= 100)
2225 return INCOMPATIBLE; /* truly mismatched types */
2226 else if (oload_champ_bv->rank[ix] >= 10)
2227 return NON_STANDARD; /* non-standard type conversions needed */
2228 }
2229
2230 return STANDARD; /* Only standard conversions needed. */
2231 }
2232
2233 /* C++: return 1 is NAME is a legitimate name for the destructor
2234 of type TYPE. If TYPE does not have a destructor, or
2235 if NAME is inappropriate for TYPE, an error is signaled. */
2236 int
2237 destructor_name_p (const char *name, const struct type *type)
2238 {
2239 /* destructors are a special case. */
2240
2241 if (name[0] == '~')
2242 {
2243 char *dname = type_name_no_tag (type);
2244 char *cp = strchr (dname, '<');
2245 unsigned int len;
2246
2247 /* Do not compare the template part for template classes. */
2248 if (cp == NULL)
2249 len = strlen (dname);
2250 else
2251 len = cp - dname;
2252 if (strlen (name + 1) != len || strncmp (dname, name + 1, len) != 0)
2253 error (_("name of destructor must equal name of class"));
2254 else
2255 return 1;
2256 }
2257 return 0;
2258 }
2259
2260 /* Helper function for check_field: Given TYPE, a structure/union,
2261 return 1 if the component named NAME from the ultimate
2262 target structure/union is defined, otherwise, return 0. */
2263
2264 static int
2265 check_field_in (struct type *type, const char *name)
2266 {
2267 int i;
2268
2269 for (i = TYPE_NFIELDS (type) - 1; i >= TYPE_N_BASECLASSES (type); i--)
2270 {
2271 char *t_field_name = TYPE_FIELD_NAME (type, i);
2272 if (t_field_name && (strcmp_iw (t_field_name, name) == 0))
2273 return 1;
2274 }
2275
2276 /* C++: If it was not found as a data field, then try to
2277 return it as a pointer to a method. */
2278
2279 /* Destructors are a special case. */
2280 if (destructor_name_p (name, type))
2281 {
2282 int m_index, f_index;
2283
2284 return get_destructor_fn_field (type, &m_index, &f_index);
2285 }
2286
2287 for (i = TYPE_NFN_FIELDS (type) - 1; i >= 0; --i)
2288 {
2289 if (strcmp_iw (TYPE_FN_FIELDLIST_NAME (type, i), name) == 0)
2290 return 1;
2291 }
2292
2293 for (i = TYPE_N_BASECLASSES (type) - 1; i >= 0; i--)
2294 if (check_field_in (TYPE_BASECLASS (type, i), name))
2295 return 1;
2296
2297 return 0;
2298 }
2299
2300
2301 /* C++: Given ARG1, a value of type (pointer to a)* structure/union,
2302 return 1 if the component named NAME from the ultimate
2303 target structure/union is defined, otherwise, return 0. */
2304
2305 int
2306 check_field (struct value *arg1, const char *name)
2307 {
2308 struct type *t;
2309
2310 arg1 = coerce_array (arg1);
2311
2312 t = value_type (arg1);
2313
2314 /* Follow pointers until we get to a non-pointer. */
2315
2316 for (;;)
2317 {
2318 CHECK_TYPEDEF (t);
2319 if (TYPE_CODE (t) != TYPE_CODE_PTR && TYPE_CODE (t) != TYPE_CODE_REF)
2320 break;
2321 t = TYPE_TARGET_TYPE (t);
2322 }
2323
2324 if (TYPE_CODE (t) != TYPE_CODE_STRUCT
2325 && TYPE_CODE (t) != TYPE_CODE_UNION)
2326 error (_("Internal error: `this' is not an aggregate"));
2327
2328 return check_field_in (t, name);
2329 }
2330
2331 /* C++: Given an aggregate type CURTYPE, and a member name NAME,
2332 return the appropriate member (or the address of the member, if
2333 WANT_ADDRESS). This function is used to resolve user expressions
2334 of the form "DOMAIN::NAME". For more details on what happens, see
2335 the comment before value_struct_elt_for_reference. */
2336
2337 struct value *
2338 value_aggregate_elt (struct type *curtype,
2339 char *name, int want_address,
2340 enum noside noside)
2341 {
2342 switch (TYPE_CODE (curtype))
2343 {
2344 case TYPE_CODE_STRUCT:
2345 case TYPE_CODE_UNION:
2346 return value_struct_elt_for_reference (curtype, 0, curtype, name, NULL,
2347 want_address, noside);
2348 case TYPE_CODE_NAMESPACE:
2349 return value_namespace_elt (curtype, name, want_address, noside);
2350 default:
2351 internal_error (__FILE__, __LINE__,
2352 _("non-aggregate type in value_aggregate_elt"));
2353 }
2354 }
2355
2356 /* C++: Given an aggregate type CURTYPE, and a member name NAME,
2357 return the address of this member as a "pointer to member"
2358 type. If INTYPE is non-null, then it will be the type
2359 of the member we are looking for. This will help us resolve
2360 "pointers to member functions". This function is used
2361 to resolve user expressions of the form "DOMAIN::NAME". */
2362
2363 static struct value *
2364 value_struct_elt_for_reference (struct type *domain, int offset,
2365 struct type *curtype, char *name,
2366 struct type *intype, int want_address,
2367 enum noside noside)
2368 {
2369 struct type *t = curtype;
2370 int i;
2371 struct value *v, *result;
2372
2373 if (TYPE_CODE (t) != TYPE_CODE_STRUCT
2374 && TYPE_CODE (t) != TYPE_CODE_UNION)
2375 error (_("Internal error: non-aggregate type to value_struct_elt_for_reference"));
2376
2377 for (i = TYPE_NFIELDS (t) - 1; i >= TYPE_N_BASECLASSES (t); i--)
2378 {
2379 char *t_field_name = TYPE_FIELD_NAME (t, i);
2380
2381 if (t_field_name && strcmp (t_field_name, name) == 0)
2382 {
2383 if (TYPE_FIELD_STATIC (t, i))
2384 {
2385 v = value_static_field (t, i);
2386 if (v == NULL)
2387 error (_("static field %s has been optimized out"),
2388 name);
2389 if (want_address)
2390 v = value_addr (v);
2391 return v;
2392 }
2393 if (TYPE_FIELD_PACKED (t, i))
2394 error (_("pointers to bitfield members not allowed"));
2395
2396 if (want_address)
2397 return value_from_longest
2398 (lookup_memberptr_type (TYPE_FIELD_TYPE (t, i), domain),
2399 offset + (LONGEST) (TYPE_FIELD_BITPOS (t, i) >> 3));
2400 else if (noside == EVAL_AVOID_SIDE_EFFECTS)
2401 return allocate_value (TYPE_FIELD_TYPE (t, i));
2402 else
2403 error (_("Cannot reference non-static field \"%s\""), name);
2404 }
2405 }
2406
2407 /* C++: If it was not found as a data field, then try to
2408 return it as a pointer to a method. */
2409
2410 /* Destructors are a special case. */
2411 if (destructor_name_p (name, t))
2412 {
2413 error (_("member pointers to destructors not implemented yet"));
2414 }
2415
2416 /* Perform all necessary dereferencing. */
2417 while (intype && TYPE_CODE (intype) == TYPE_CODE_PTR)
2418 intype = TYPE_TARGET_TYPE (intype);
2419
2420 for (i = TYPE_NFN_FIELDS (t) - 1; i >= 0; --i)
2421 {
2422 char *t_field_name = TYPE_FN_FIELDLIST_NAME (t, i);
2423 char dem_opname[64];
2424
2425 if (strncmp (t_field_name, "__", 2) == 0 ||
2426 strncmp (t_field_name, "op", 2) == 0 ||
2427 strncmp (t_field_name, "type", 4) == 0)
2428 {
2429 if (cplus_demangle_opname (t_field_name, dem_opname, DMGL_ANSI))
2430 t_field_name = dem_opname;
2431 else if (cplus_demangle_opname (t_field_name, dem_opname, 0))
2432 t_field_name = dem_opname;
2433 }
2434 if (t_field_name && strcmp (t_field_name, name) == 0)
2435 {
2436 int j = TYPE_FN_FIELDLIST_LENGTH (t, i);
2437 struct fn_field *f = TYPE_FN_FIELDLIST1 (t, i);
2438
2439 check_stub_method_group (t, i);
2440
2441 if (intype == 0 && j > 1)
2442 error (_("non-unique member `%s' requires type instantiation"), name);
2443 if (intype)
2444 {
2445 while (j--)
2446 if (TYPE_FN_FIELD_TYPE (f, j) == intype)
2447 break;
2448 if (j < 0)
2449 error (_("no member function matches that type instantiation"));
2450 }
2451 else
2452 j = 0;
2453
2454 if (TYPE_FN_FIELD_STATIC_P (f, j))
2455 {
2456 struct symbol *s = lookup_symbol (TYPE_FN_FIELD_PHYSNAME (f, j),
2457 0, VAR_DOMAIN, 0, NULL);
2458 if (s == NULL)
2459 return NULL;
2460
2461 if (want_address)
2462 return value_addr (read_var_value (s, 0));
2463 else
2464 return read_var_value (s, 0);
2465 }
2466
2467 if (TYPE_FN_FIELD_VIRTUAL_P (f, j))
2468 {
2469 if (want_address)
2470 {
2471 result = allocate_value
2472 (lookup_methodptr_type (TYPE_FN_FIELD_TYPE (f, j)));
2473 cplus_make_method_ptr (value_contents_writeable (result),
2474 TYPE_FN_FIELD_VOFFSET (f, j), 1);
2475 }
2476 else if (noside == EVAL_AVOID_SIDE_EFFECTS)
2477 return allocate_value (TYPE_FN_FIELD_TYPE (f, j));
2478 else
2479 error (_("Cannot reference virtual member function \"%s\""),
2480 name);
2481 }
2482 else
2483 {
2484 struct symbol *s = lookup_symbol (TYPE_FN_FIELD_PHYSNAME (f, j),
2485 0, VAR_DOMAIN, 0, NULL);
2486 if (s == NULL)
2487 return NULL;
2488
2489 v = read_var_value (s, 0);
2490 if (!want_address)
2491 result = v;
2492 else
2493 {
2494 result = allocate_value (lookup_methodptr_type (TYPE_FN_FIELD_TYPE (f, j)));
2495 cplus_make_method_ptr (value_contents_writeable (result),
2496 VALUE_ADDRESS (v), 0);
2497 }
2498 }
2499 return result;
2500 }
2501 }
2502 for (i = TYPE_N_BASECLASSES (t) - 1; i >= 0; i--)
2503 {
2504 struct value *v;
2505 int base_offset;
2506
2507 if (BASETYPE_VIA_VIRTUAL (t, i))
2508 base_offset = 0;
2509 else
2510 base_offset = TYPE_BASECLASS_BITPOS (t, i) / 8;
2511 v = value_struct_elt_for_reference (domain,
2512 offset + base_offset,
2513 TYPE_BASECLASS (t, i),
2514 name,
2515 intype, want_address,
2516 noside);
2517 if (v)
2518 return v;
2519 }
2520
2521 /* As a last chance, pretend that CURTYPE is a namespace, and look
2522 it up that way; this (frequently) works for types nested inside
2523 classes. */
2524
2525 return value_maybe_namespace_elt (curtype, name, want_address, noside);
2526 }
2527
2528 /* C++: Return the member NAME of the namespace given by the type
2529 CURTYPE. */
2530
2531 static struct value *
2532 value_namespace_elt (const struct type *curtype,
2533 char *name, int want_address,
2534 enum noside noside)
2535 {
2536 struct value *retval = value_maybe_namespace_elt (curtype, name,
2537 want_address, noside);
2538
2539 if (retval == NULL)
2540 error (_("No symbol \"%s\" in namespace \"%s\"."), name,
2541 TYPE_TAG_NAME (curtype));
2542
2543 return retval;
2544 }
2545
2546 /* A helper function used by value_namespace_elt and
2547 value_struct_elt_for_reference. It looks up NAME inside the
2548 context CURTYPE; this works if CURTYPE is a namespace or if CURTYPE
2549 is a class and NAME refers to a type in CURTYPE itself (as opposed
2550 to, say, some base class of CURTYPE). */
2551
2552 static struct value *
2553 value_maybe_namespace_elt (const struct type *curtype,
2554 char *name, int want_address,
2555 enum noside noside)
2556 {
2557 const char *namespace_name = TYPE_TAG_NAME (curtype);
2558 struct symbol *sym;
2559 struct value *result;
2560
2561 sym = cp_lookup_symbol_namespace (namespace_name, name, NULL,
2562 get_selected_block (0), VAR_DOMAIN,
2563 NULL);
2564
2565 if (sym == NULL)
2566 return NULL;
2567 else if ((noside == EVAL_AVOID_SIDE_EFFECTS)
2568 && (SYMBOL_CLASS (sym) == LOC_TYPEDEF))
2569 result = allocate_value (SYMBOL_TYPE (sym));
2570 else
2571 result = value_of_variable (sym, get_selected_block (0));
2572
2573 if (result && want_address)
2574 result = value_addr (result);
2575
2576 return result;
2577 }
2578
2579 /* Given a pointer value V, find the real (RTTI) type
2580 of the object it points to.
2581 Other parameters FULL, TOP, USING_ENC as with value_rtti_type()
2582 and refer to the values computed for the object pointed to. */
2583
2584 struct type *
2585 value_rtti_target_type (struct value *v, int *full, int *top, int *using_enc)
2586 {
2587 struct value *target;
2588
2589 target = value_ind (v);
2590
2591 return value_rtti_type (target, full, top, using_enc);
2592 }
2593
2594 /* Given a value pointed to by ARGP, check its real run-time type, and
2595 if that is different from the enclosing type, create a new value
2596 using the real run-time type as the enclosing type (and of the same
2597 type as ARGP) and return it, with the embedded offset adjusted to
2598 be the correct offset to the enclosed object
2599 RTYPE is the type, and XFULL, XTOP, and XUSING_ENC are the other
2600 parameters, computed by value_rtti_type(). If these are available,
2601 they can be supplied and a second call to value_rtti_type() is avoided.
2602 (Pass RTYPE == NULL if they're not available */
2603
2604 struct value *
2605 value_full_object (struct value *argp, struct type *rtype, int xfull, int xtop,
2606 int xusing_enc)
2607 {
2608 struct type *real_type;
2609 int full = 0;
2610 int top = -1;
2611 int using_enc = 0;
2612 struct value *new_val;
2613
2614 if (rtype)
2615 {
2616 real_type = rtype;
2617 full = xfull;
2618 top = xtop;
2619 using_enc = xusing_enc;
2620 }
2621 else
2622 real_type = value_rtti_type (argp, &full, &top, &using_enc);
2623
2624 /* If no RTTI data, or if object is already complete, do nothing */
2625 if (!real_type || real_type == value_enclosing_type (argp))
2626 return argp;
2627
2628 /* If we have the full object, but for some reason the enclosing
2629 type is wrong, set it *//* pai: FIXME -- sounds iffy */
2630 if (full)
2631 {
2632 argp = value_change_enclosing_type (argp, real_type);
2633 return argp;
2634 }
2635
2636 /* Check if object is in memory */
2637 if (VALUE_LVAL (argp) != lval_memory)
2638 {
2639 warning (_("Couldn't retrieve complete object of RTTI type %s; object may be in register(s)."), TYPE_NAME (real_type));
2640
2641 return argp;
2642 }
2643
2644 /* All other cases -- retrieve the complete object */
2645 /* Go back by the computed top_offset from the beginning of the object,
2646 adjusting for the embedded offset of argp if that's what value_rtti_type
2647 used for its computation. */
2648 new_val = value_at_lazy (real_type, VALUE_ADDRESS (argp) - top +
2649 (using_enc ? 0 : value_embedded_offset (argp)));
2650 deprecated_set_value_type (new_val, value_type (argp));
2651 set_value_embedded_offset (new_val, (using_enc
2652 ? top + value_embedded_offset (argp)
2653 : top));
2654 return new_val;
2655 }
2656
2657
2658
2659
2660 /* Return the value of the local variable, if one exists.
2661 Flag COMPLAIN signals an error if the request is made in an
2662 inappropriate context. */
2663
2664 struct value *
2665 value_of_local (const char *name, int complain)
2666 {
2667 struct symbol *func, *sym;
2668 struct block *b;
2669 struct value * ret;
2670
2671 if (deprecated_selected_frame == 0)
2672 {
2673 if (complain)
2674 error (_("no frame selected"));
2675 else
2676 return 0;
2677 }
2678
2679 func = get_frame_function (deprecated_selected_frame);
2680 if (!func)
2681 {
2682 if (complain)
2683 error (_("no `%s' in nameless context"), name);
2684 else
2685 return 0;
2686 }
2687
2688 b = SYMBOL_BLOCK_VALUE (func);
2689 if (dict_empty (BLOCK_DICT (b)))
2690 {
2691 if (complain)
2692 error (_("no args, no `%s'"), name);
2693 else
2694 return 0;
2695 }
2696
2697 /* Calling lookup_block_symbol is necessary to get the LOC_REGISTER
2698 symbol instead of the LOC_ARG one (if both exist). */
2699 sym = lookup_block_symbol (b, name, NULL, VAR_DOMAIN);
2700 if (sym == NULL)
2701 {
2702 if (complain)
2703 error (_("current stack frame does not contain a variable named `%s'"), name);
2704 else
2705 return NULL;
2706 }
2707
2708 ret = read_var_value (sym, deprecated_selected_frame);
2709 if (ret == 0 && complain)
2710 error (_("`%s' argument unreadable"), name);
2711 return ret;
2712 }
2713
2714 /* C++/Objective-C: return the value of the class instance variable,
2715 if one exists. Flag COMPLAIN signals an error if the request is
2716 made in an inappropriate context. */
2717
2718 struct value *
2719 value_of_this (int complain)
2720 {
2721 if (current_language->la_language == language_objc)
2722 return value_of_local ("self", complain);
2723 else
2724 return value_of_local ("this", complain);
2725 }
2726
2727 /* Create a slice (sub-string, sub-array) of ARRAY, that is LENGTH elements
2728 long, starting at LOWBOUND. The result has the same lower bound as
2729 the original ARRAY. */
2730
2731 struct value *
2732 value_slice (struct value *array, int lowbound, int length)
2733 {
2734 struct type *slice_range_type, *slice_type, *range_type;
2735 LONGEST lowerbound, upperbound;
2736 struct value *slice;
2737 struct type *array_type;
2738 array_type = check_typedef (value_type (array));
2739 if (TYPE_CODE (array_type) != TYPE_CODE_ARRAY
2740 && TYPE_CODE (array_type) != TYPE_CODE_STRING
2741 && TYPE_CODE (array_type) != TYPE_CODE_BITSTRING)
2742 error (_("cannot take slice of non-array"));
2743 range_type = TYPE_INDEX_TYPE (array_type);
2744 if (get_discrete_bounds (range_type, &lowerbound, &upperbound) < 0)
2745 error (_("slice from bad array or bitstring"));
2746 if (lowbound < lowerbound || length < 0
2747 || lowbound + length - 1 > upperbound)
2748 error (_("slice out of range"));
2749 /* FIXME-type-allocation: need a way to free this type when we are
2750 done with it. */
2751 slice_range_type = create_range_type ((struct type *) NULL,
2752 TYPE_TARGET_TYPE (range_type),
2753 lowbound, lowbound + length - 1);
2754 if (TYPE_CODE (array_type) == TYPE_CODE_BITSTRING)
2755 {
2756 int i;
2757 slice_type = create_set_type ((struct type *) NULL, slice_range_type);
2758 TYPE_CODE (slice_type) = TYPE_CODE_BITSTRING;
2759 slice = value_zero (slice_type, not_lval);
2760 for (i = 0; i < length; i++)
2761 {
2762 int element = value_bit_index (array_type,
2763 value_contents (array),
2764 lowbound + i);
2765 if (element < 0)
2766 error (_("internal error accessing bitstring"));
2767 else if (element > 0)
2768 {
2769 int j = i % TARGET_CHAR_BIT;
2770 if (BITS_BIG_ENDIAN)
2771 j = TARGET_CHAR_BIT - 1 - j;
2772 value_contents_raw (slice)[i / TARGET_CHAR_BIT] |= (1 << j);
2773 }
2774 }
2775 /* We should set the address, bitssize, and bitspos, so the clice
2776 can be used on the LHS, but that may require extensions to
2777 value_assign. For now, just leave as a non_lval. FIXME. */
2778 }
2779 else
2780 {
2781 struct type *element_type = TYPE_TARGET_TYPE (array_type);
2782 LONGEST offset
2783 = (lowbound - lowerbound) * TYPE_LENGTH (check_typedef (element_type));
2784 slice_type = create_array_type ((struct type *) NULL, element_type,
2785 slice_range_type);
2786 TYPE_CODE (slice_type) = TYPE_CODE (array_type);
2787 slice = allocate_value (slice_type);
2788 if (value_lazy (array))
2789 set_value_lazy (slice, 1);
2790 else
2791 memcpy (value_contents_writeable (slice),
2792 value_contents (array) + offset,
2793 TYPE_LENGTH (slice_type));
2794 if (VALUE_LVAL (array) == lval_internalvar)
2795 VALUE_LVAL (slice) = lval_internalvar_component;
2796 else
2797 VALUE_LVAL (slice) = VALUE_LVAL (array);
2798 VALUE_ADDRESS (slice) = VALUE_ADDRESS (array);
2799 VALUE_FRAME_ID (slice) = VALUE_FRAME_ID (array);
2800 set_value_offset (slice, value_offset (array) + offset);
2801 }
2802 return slice;
2803 }
2804
2805 /* Create a value for a FORTRAN complex number. Currently most of
2806 the time values are coerced to COMPLEX*16 (i.e. a complex number
2807 composed of 2 doubles. This really should be a smarter routine
2808 that figures out precision inteligently as opposed to assuming
2809 doubles. FIXME: fmb */
2810
2811 struct value *
2812 value_literal_complex (struct value *arg1, struct value *arg2, struct type *type)
2813 {
2814 struct value *val;
2815 struct type *real_type = TYPE_TARGET_TYPE (type);
2816
2817 val = allocate_value (type);
2818 arg1 = value_cast (real_type, arg1);
2819 arg2 = value_cast (real_type, arg2);
2820
2821 memcpy (value_contents_raw (val),
2822 value_contents (arg1), TYPE_LENGTH (real_type));
2823 memcpy (value_contents_raw (val) + TYPE_LENGTH (real_type),
2824 value_contents (arg2), TYPE_LENGTH (real_type));
2825 return val;
2826 }
2827
2828 /* Cast a value into the appropriate complex data type. */
2829
2830 static struct value *
2831 cast_into_complex (struct type *type, struct value *val)
2832 {
2833 struct type *real_type = TYPE_TARGET_TYPE (type);
2834 if (TYPE_CODE (value_type (val)) == TYPE_CODE_COMPLEX)
2835 {
2836 struct type *val_real_type = TYPE_TARGET_TYPE (value_type (val));
2837 struct value *re_val = allocate_value (val_real_type);
2838 struct value *im_val = allocate_value (val_real_type);
2839
2840 memcpy (value_contents_raw (re_val),
2841 value_contents (val), TYPE_LENGTH (val_real_type));
2842 memcpy (value_contents_raw (im_val),
2843 value_contents (val) + TYPE_LENGTH (val_real_type),
2844 TYPE_LENGTH (val_real_type));
2845
2846 return value_literal_complex (re_val, im_val, type);
2847 }
2848 else if (TYPE_CODE (value_type (val)) == TYPE_CODE_FLT
2849 || TYPE_CODE (value_type (val)) == TYPE_CODE_INT)
2850 return value_literal_complex (val, value_zero (real_type, not_lval), type);
2851 else
2852 error (_("cannot cast non-number to complex"));
2853 }
2854
2855 void
2856 _initialize_valops (void)
2857 {
2858 add_setshow_boolean_cmd ("overload-resolution", class_support,
2859 &overload_resolution, _("\
2860 Set overload resolution in evaluating C++ functions."), _("\
2861 Show overload resolution in evaluating C++ functions."), NULL,
2862 NULL,
2863 show_overload_resolution,
2864 &setlist, &showlist);
2865 overload_resolution = 1;
2866 }