2002-01-04 Daniel Jacobowitz <drow@mvista.com>
[deliverable/binutils-gdb.git] / gdb / valops.c
1 /* Perform non-arithmetic operations on values, for GDB.
2 Copyright 1986, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994,
3 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002
4 Free Software Foundation, Inc.
5
6 This file is part of GDB.
7
8 This program is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 2 of the License, or
11 (at your option) any later version.
12
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
17
18 You should have received a copy of the GNU General Public License
19 along with this program; if not, write to the Free Software
20 Foundation, Inc., 59 Temple Place - Suite 330,
21 Boston, MA 02111-1307, USA. */
22
23 #include "defs.h"
24 #include "symtab.h"
25 #include "gdbtypes.h"
26 #include "value.h"
27 #include "frame.h"
28 #include "inferior.h"
29 #include "gdbcore.h"
30 #include "target.h"
31 #include "demangle.h"
32 #include "language.h"
33 #include "gdbcmd.h"
34 #include "regcache.h"
35 #include "cp-abi.h"
36
37 #include <errno.h>
38 #include "gdb_string.h"
39
40 /* Flag indicating HP compilers were used; needed to correctly handle some
41 value operations with HP aCC code/runtime. */
42 extern int hp_som_som_object_present;
43
44 extern int overload_debug;
45 /* Local functions. */
46
47 static int typecmp (int staticp, struct type *t1[], struct value *t2[]);
48
49 static CORE_ADDR find_function_addr (struct value *, struct type **);
50 static struct value *value_arg_coerce (struct value *, struct type *, int);
51
52
53 static CORE_ADDR value_push (CORE_ADDR, struct value *);
54
55 static struct value *search_struct_field (char *, struct value *, int,
56 struct type *, int);
57
58 static struct value *search_struct_method (char *, struct value **,
59 struct value **,
60 int, int *, struct type *);
61
62 static int check_field_in (struct type *, const char *);
63
64 static CORE_ADDR allocate_space_in_inferior (int);
65
66 static struct value *cast_into_complex (struct type *, struct value *);
67
68 static struct fn_field *find_method_list (struct value ** argp, char *method,
69 int offset, int *static_memfuncp,
70 struct type *type, int *num_fns,
71 struct type **basetype,
72 int *boffset);
73
74 void _initialize_valops (void);
75
76 /* Flag for whether we want to abandon failed expression evals by default. */
77
78 #if 0
79 static int auto_abandon = 0;
80 #endif
81
82 int overload_resolution = 0;
83
84 /* This boolean tells what gdb should do if a signal is received while in
85 a function called from gdb (call dummy). If set, gdb unwinds the stack
86 and restore the context to what as it was before the call.
87 The default is to stop in the frame where the signal was received. */
88
89 int unwind_on_signal_p = 0;
90 \f
91
92
93 /* Find the address of function name NAME in the inferior. */
94
95 struct value *
96 find_function_in_inferior (char *name)
97 {
98 register struct symbol *sym;
99 sym = lookup_symbol (name, 0, VAR_NAMESPACE, 0, NULL);
100 if (sym != NULL)
101 {
102 if (SYMBOL_CLASS (sym) != LOC_BLOCK)
103 {
104 error ("\"%s\" exists in this program but is not a function.",
105 name);
106 }
107 return value_of_variable (sym, NULL);
108 }
109 else
110 {
111 struct minimal_symbol *msymbol = lookup_minimal_symbol (name, NULL, NULL);
112 if (msymbol != NULL)
113 {
114 struct type *type;
115 CORE_ADDR maddr;
116 type = lookup_pointer_type (builtin_type_char);
117 type = lookup_function_type (type);
118 type = lookup_pointer_type (type);
119 maddr = SYMBOL_VALUE_ADDRESS (msymbol);
120 return value_from_pointer (type, maddr);
121 }
122 else
123 {
124 if (!target_has_execution)
125 error ("evaluation of this expression requires the target program to be active");
126 else
127 error ("evaluation of this expression requires the program to have a function \"%s\".", name);
128 }
129 }
130 }
131
132 /* Allocate NBYTES of space in the inferior using the inferior's malloc
133 and return a value that is a pointer to the allocated space. */
134
135 struct value *
136 value_allocate_space_in_inferior (int len)
137 {
138 struct value *blocklen;
139 struct value *val = find_function_in_inferior ("malloc");
140
141 blocklen = value_from_longest (builtin_type_int, (LONGEST) len);
142 val = call_function_by_hand (val, 1, &blocklen);
143 if (value_logical_not (val))
144 {
145 if (!target_has_execution)
146 error ("No memory available to program now: you need to start the target first");
147 else
148 error ("No memory available to program: call to malloc failed");
149 }
150 return val;
151 }
152
153 static CORE_ADDR
154 allocate_space_in_inferior (int len)
155 {
156 return value_as_long (value_allocate_space_in_inferior (len));
157 }
158
159 /* Cast value ARG2 to type TYPE and return as a value.
160 More general than a C cast: accepts any two types of the same length,
161 and if ARG2 is an lvalue it can be cast into anything at all. */
162 /* In C++, casts may change pointer or object representations. */
163
164 struct value *
165 value_cast (struct type *type, struct value *arg2)
166 {
167 register enum type_code code1;
168 register enum type_code code2;
169 register int scalar;
170 struct type *type2;
171
172 int convert_to_boolean = 0;
173
174 if (VALUE_TYPE (arg2) == type)
175 return arg2;
176
177 CHECK_TYPEDEF (type);
178 code1 = TYPE_CODE (type);
179 COERCE_REF (arg2);
180 type2 = check_typedef (VALUE_TYPE (arg2));
181
182 /* A cast to an undetermined-length array_type, such as (TYPE [])OBJECT,
183 is treated like a cast to (TYPE [N])OBJECT,
184 where N is sizeof(OBJECT)/sizeof(TYPE). */
185 if (code1 == TYPE_CODE_ARRAY)
186 {
187 struct type *element_type = TYPE_TARGET_TYPE (type);
188 unsigned element_length = TYPE_LENGTH (check_typedef (element_type));
189 if (element_length > 0
190 && TYPE_ARRAY_UPPER_BOUND_TYPE (type) == BOUND_CANNOT_BE_DETERMINED)
191 {
192 struct type *range_type = TYPE_INDEX_TYPE (type);
193 int val_length = TYPE_LENGTH (type2);
194 LONGEST low_bound, high_bound, new_length;
195 if (get_discrete_bounds (range_type, &low_bound, &high_bound) < 0)
196 low_bound = 0, high_bound = 0;
197 new_length = val_length / element_length;
198 if (val_length % element_length != 0)
199 warning ("array element type size does not divide object size in cast");
200 /* FIXME-type-allocation: need a way to free this type when we are
201 done with it. */
202 range_type = create_range_type ((struct type *) NULL,
203 TYPE_TARGET_TYPE (range_type),
204 low_bound,
205 new_length + low_bound - 1);
206 VALUE_TYPE (arg2) = create_array_type ((struct type *) NULL,
207 element_type, range_type);
208 return arg2;
209 }
210 }
211
212 if (current_language->c_style_arrays
213 && TYPE_CODE (type2) == TYPE_CODE_ARRAY)
214 arg2 = value_coerce_array (arg2);
215
216 if (TYPE_CODE (type2) == TYPE_CODE_FUNC)
217 arg2 = value_coerce_function (arg2);
218
219 type2 = check_typedef (VALUE_TYPE (arg2));
220 COERCE_VARYING_ARRAY (arg2, type2);
221 code2 = TYPE_CODE (type2);
222
223 if (code1 == TYPE_CODE_COMPLEX)
224 return cast_into_complex (type, arg2);
225 if (code1 == TYPE_CODE_BOOL)
226 {
227 code1 = TYPE_CODE_INT;
228 convert_to_boolean = 1;
229 }
230 if (code1 == TYPE_CODE_CHAR)
231 code1 = TYPE_CODE_INT;
232 if (code2 == TYPE_CODE_BOOL || code2 == TYPE_CODE_CHAR)
233 code2 = TYPE_CODE_INT;
234
235 scalar = (code2 == TYPE_CODE_INT || code2 == TYPE_CODE_FLT
236 || code2 == TYPE_CODE_ENUM || code2 == TYPE_CODE_RANGE);
237
238 if (code1 == TYPE_CODE_STRUCT
239 && code2 == TYPE_CODE_STRUCT
240 && TYPE_NAME (type) != 0)
241 {
242 /* Look in the type of the source to see if it contains the
243 type of the target as a superclass. If so, we'll need to
244 offset the object in addition to changing its type. */
245 struct value *v = search_struct_field (type_name_no_tag (type),
246 arg2, 0, type2, 1);
247 if (v)
248 {
249 VALUE_TYPE (v) = type;
250 return v;
251 }
252 }
253 if (code1 == TYPE_CODE_FLT && scalar)
254 return value_from_double (type, value_as_double (arg2));
255 else if ((code1 == TYPE_CODE_INT || code1 == TYPE_CODE_ENUM
256 || code1 == TYPE_CODE_RANGE)
257 && (scalar || code2 == TYPE_CODE_PTR))
258 {
259 LONGEST longest;
260
261 if (hp_som_som_object_present && /* if target compiled by HP aCC */
262 (code2 == TYPE_CODE_PTR))
263 {
264 unsigned int *ptr;
265 struct value *retvalp;
266
267 switch (TYPE_CODE (TYPE_TARGET_TYPE (type2)))
268 {
269 /* With HP aCC, pointers to data members have a bias */
270 case TYPE_CODE_MEMBER:
271 retvalp = value_from_longest (type, value_as_long (arg2));
272 /* force evaluation */
273 ptr = (unsigned int *) VALUE_CONTENTS (retvalp);
274 *ptr &= ~0x20000000; /* zap 29th bit to remove bias */
275 return retvalp;
276
277 /* While pointers to methods don't really point to a function */
278 case TYPE_CODE_METHOD:
279 error ("Pointers to methods not supported with HP aCC");
280
281 default:
282 break; /* fall out and go to normal handling */
283 }
284 }
285
286 /* When we cast pointers to integers, we mustn't use
287 POINTER_TO_ADDRESS to find the address the pointer
288 represents, as value_as_long would. GDB should evaluate
289 expressions just as the compiler would --- and the compiler
290 sees a cast as a simple reinterpretation of the pointer's
291 bits. */
292 if (code2 == TYPE_CODE_PTR)
293 longest = extract_unsigned_integer (VALUE_CONTENTS (arg2),
294 TYPE_LENGTH (type2));
295 else
296 longest = value_as_long (arg2);
297 return value_from_longest (type, convert_to_boolean ?
298 (LONGEST) (longest ? 1 : 0) : longest);
299 }
300 else if (code1 == TYPE_CODE_PTR && (code2 == TYPE_CODE_INT ||
301 code2 == TYPE_CODE_ENUM ||
302 code2 == TYPE_CODE_RANGE))
303 {
304 /* TYPE_LENGTH (type) is the length of a pointer, but we really
305 want the length of an address! -- we are really dealing with
306 addresses (i.e., gdb representations) not pointers (i.e.,
307 target representations) here.
308
309 This allows things like "print *(int *)0x01000234" to work
310 without printing a misleading message -- which would
311 otherwise occur when dealing with a target having two byte
312 pointers and four byte addresses. */
313
314 int addr_bit = TARGET_ADDR_BIT;
315
316 LONGEST longest = value_as_long (arg2);
317 if (addr_bit < sizeof (LONGEST) * HOST_CHAR_BIT)
318 {
319 if (longest >= ((LONGEST) 1 << addr_bit)
320 || longest <= -((LONGEST) 1 << addr_bit))
321 warning ("value truncated");
322 }
323 return value_from_longest (type, longest);
324 }
325 else if (TYPE_LENGTH (type) == TYPE_LENGTH (type2))
326 {
327 if (code1 == TYPE_CODE_PTR && code2 == TYPE_CODE_PTR)
328 {
329 struct type *t1 = check_typedef (TYPE_TARGET_TYPE (type));
330 struct type *t2 = check_typedef (TYPE_TARGET_TYPE (type2));
331 if (TYPE_CODE (t1) == TYPE_CODE_STRUCT
332 && TYPE_CODE (t2) == TYPE_CODE_STRUCT
333 && !value_logical_not (arg2))
334 {
335 struct value *v;
336
337 /* Look in the type of the source to see if it contains the
338 type of the target as a superclass. If so, we'll need to
339 offset the pointer rather than just change its type. */
340 if (TYPE_NAME (t1) != NULL)
341 {
342 v = search_struct_field (type_name_no_tag (t1),
343 value_ind (arg2), 0, t2, 1);
344 if (v)
345 {
346 v = value_addr (v);
347 VALUE_TYPE (v) = type;
348 return v;
349 }
350 }
351
352 /* Look in the type of the target to see if it contains the
353 type of the source as a superclass. If so, we'll need to
354 offset the pointer rather than just change its type.
355 FIXME: This fails silently with virtual inheritance. */
356 if (TYPE_NAME (t2) != NULL)
357 {
358 v = search_struct_field (type_name_no_tag (t2),
359 value_zero (t1, not_lval), 0, t1, 1);
360 if (v)
361 {
362 struct value *v2 = value_ind (arg2);
363 VALUE_ADDRESS (v2) -= VALUE_ADDRESS (v)
364 + VALUE_OFFSET (v);
365
366 /* JYG: adjust the new pointer value and
367 embedded offset. */
368 v2->aligner.contents[0] -= VALUE_EMBEDDED_OFFSET (v);
369 VALUE_EMBEDDED_OFFSET (v2) = 0;
370
371 v2 = value_addr (v2);
372 VALUE_TYPE (v2) = type;
373 return v2;
374 }
375 }
376 }
377 /* No superclass found, just fall through to change ptr type. */
378 }
379 VALUE_TYPE (arg2) = type;
380 arg2 = value_change_enclosing_type (arg2, type);
381 VALUE_POINTED_TO_OFFSET (arg2) = 0; /* pai: chk_val */
382 return arg2;
383 }
384 else if (chill_varying_type (type))
385 {
386 struct type *range1, *range2, *eltype1, *eltype2;
387 struct value *val;
388 int count1, count2;
389 LONGEST low_bound, high_bound;
390 char *valaddr, *valaddr_data;
391 /* For lint warning about eltype2 possibly uninitialized: */
392 eltype2 = NULL;
393 if (code2 == TYPE_CODE_BITSTRING)
394 error ("not implemented: converting bitstring to varying type");
395 if ((code2 != TYPE_CODE_ARRAY && code2 != TYPE_CODE_STRING)
396 || (eltype1 = check_typedef (TYPE_TARGET_TYPE (TYPE_FIELD_TYPE (type, 1))),
397 eltype2 = check_typedef (TYPE_TARGET_TYPE (type2)),
398 (TYPE_LENGTH (eltype1) != TYPE_LENGTH (eltype2)
399 /* || TYPE_CODE (eltype1) != TYPE_CODE (eltype2) */ )))
400 error ("Invalid conversion to varying type");
401 range1 = TYPE_FIELD_TYPE (TYPE_FIELD_TYPE (type, 1), 0);
402 range2 = TYPE_FIELD_TYPE (type2, 0);
403 if (get_discrete_bounds (range1, &low_bound, &high_bound) < 0)
404 count1 = -1;
405 else
406 count1 = high_bound - low_bound + 1;
407 if (get_discrete_bounds (range2, &low_bound, &high_bound) < 0)
408 count1 = -1, count2 = 0; /* To force error before */
409 else
410 count2 = high_bound - low_bound + 1;
411 if (count2 > count1)
412 error ("target varying type is too small");
413 val = allocate_value (type);
414 valaddr = VALUE_CONTENTS_RAW (val);
415 valaddr_data = valaddr + TYPE_FIELD_BITPOS (type, 1) / 8;
416 /* Set val's __var_length field to count2. */
417 store_signed_integer (valaddr, TYPE_LENGTH (TYPE_FIELD_TYPE (type, 0)),
418 count2);
419 /* Set the __var_data field to count2 elements copied from arg2. */
420 memcpy (valaddr_data, VALUE_CONTENTS (arg2),
421 count2 * TYPE_LENGTH (eltype2));
422 /* Zero the rest of the __var_data field of val. */
423 memset (valaddr_data + count2 * TYPE_LENGTH (eltype2), '\0',
424 (count1 - count2) * TYPE_LENGTH (eltype2));
425 return val;
426 }
427 else if (VALUE_LVAL (arg2) == lval_memory)
428 {
429 return value_at_lazy (type, VALUE_ADDRESS (arg2) + VALUE_OFFSET (arg2),
430 VALUE_BFD_SECTION (arg2));
431 }
432 else if (code1 == TYPE_CODE_VOID)
433 {
434 return value_zero (builtin_type_void, not_lval);
435 }
436 else
437 {
438 error ("Invalid cast.");
439 return 0;
440 }
441 }
442
443 /* Create a value of type TYPE that is zero, and return it. */
444
445 struct value *
446 value_zero (struct type *type, enum lval_type lv)
447 {
448 struct value *val = allocate_value (type);
449
450 memset (VALUE_CONTENTS (val), 0, TYPE_LENGTH (check_typedef (type)));
451 VALUE_LVAL (val) = lv;
452
453 return val;
454 }
455
456 /* Return a value with type TYPE located at ADDR.
457
458 Call value_at only if the data needs to be fetched immediately;
459 if we can be 'lazy' and defer the fetch, perhaps indefinately, call
460 value_at_lazy instead. value_at_lazy simply records the address of
461 the data and sets the lazy-evaluation-required flag. The lazy flag
462 is tested in the VALUE_CONTENTS macro, which is used if and when
463 the contents are actually required.
464
465 Note: value_at does *NOT* handle embedded offsets; perform such
466 adjustments before or after calling it. */
467
468 struct value *
469 value_at (struct type *type, CORE_ADDR addr, asection *sect)
470 {
471 struct value *val;
472
473 if (TYPE_CODE (check_typedef (type)) == TYPE_CODE_VOID)
474 error ("Attempt to dereference a generic pointer.");
475
476 val = allocate_value (type);
477
478 read_memory (addr, VALUE_CONTENTS_ALL_RAW (val), TYPE_LENGTH (type));
479
480 VALUE_LVAL (val) = lval_memory;
481 VALUE_ADDRESS (val) = addr;
482 VALUE_BFD_SECTION (val) = sect;
483
484 return val;
485 }
486
487 /* Return a lazy value with type TYPE located at ADDR (cf. value_at). */
488
489 struct value *
490 value_at_lazy (struct type *type, CORE_ADDR addr, asection *sect)
491 {
492 struct value *val;
493
494 if (TYPE_CODE (check_typedef (type)) == TYPE_CODE_VOID)
495 error ("Attempt to dereference a generic pointer.");
496
497 val = allocate_value (type);
498
499 VALUE_LVAL (val) = lval_memory;
500 VALUE_ADDRESS (val) = addr;
501 VALUE_LAZY (val) = 1;
502 VALUE_BFD_SECTION (val) = sect;
503
504 return val;
505 }
506
507 /* Called only from the VALUE_CONTENTS and VALUE_CONTENTS_ALL macros,
508 if the current data for a variable needs to be loaded into
509 VALUE_CONTENTS(VAL). Fetches the data from the user's process, and
510 clears the lazy flag to indicate that the data in the buffer is valid.
511
512 If the value is zero-length, we avoid calling read_memory, which would
513 abort. We mark the value as fetched anyway -- all 0 bytes of it.
514
515 This function returns a value because it is used in the VALUE_CONTENTS
516 macro as part of an expression, where a void would not work. The
517 value is ignored. */
518
519 int
520 value_fetch_lazy (struct value *val)
521 {
522 CORE_ADDR addr = VALUE_ADDRESS (val) + VALUE_OFFSET (val);
523 int length = TYPE_LENGTH (VALUE_ENCLOSING_TYPE (val));
524
525 struct type *type = VALUE_TYPE (val);
526 if (length)
527 read_memory (addr, VALUE_CONTENTS_ALL_RAW (val), length);
528
529 VALUE_LAZY (val) = 0;
530 return 0;
531 }
532
533
534 /* Store the contents of FROMVAL into the location of TOVAL.
535 Return a new value with the location of TOVAL and contents of FROMVAL. */
536
537 struct value *
538 value_assign (struct value *toval, struct value *fromval)
539 {
540 register struct type *type;
541 struct value *val;
542 char *raw_buffer = (char*) alloca (MAX_REGISTER_RAW_SIZE);
543 int use_buffer = 0;
544
545 if (!toval->modifiable)
546 error ("Left operand of assignment is not a modifiable lvalue.");
547
548 COERCE_REF (toval);
549
550 type = VALUE_TYPE (toval);
551 if (VALUE_LVAL (toval) != lval_internalvar)
552 fromval = value_cast (type, fromval);
553 else
554 COERCE_ARRAY (fromval);
555 CHECK_TYPEDEF (type);
556
557 /* If TOVAL is a special machine register requiring conversion
558 of program values to a special raw format,
559 convert FROMVAL's contents now, with result in `raw_buffer',
560 and set USE_BUFFER to the number of bytes to write. */
561
562 if (VALUE_REGNO (toval) >= 0)
563 {
564 int regno = VALUE_REGNO (toval);
565 if (REGISTER_CONVERTIBLE (regno))
566 {
567 struct type *fromtype = check_typedef (VALUE_TYPE (fromval));
568 REGISTER_CONVERT_TO_RAW (fromtype, regno,
569 VALUE_CONTENTS (fromval), raw_buffer);
570 use_buffer = REGISTER_RAW_SIZE (regno);
571 }
572 }
573
574 switch (VALUE_LVAL (toval))
575 {
576 case lval_internalvar:
577 set_internalvar (VALUE_INTERNALVAR (toval), fromval);
578 val = value_copy (VALUE_INTERNALVAR (toval)->value);
579 val = value_change_enclosing_type (val, VALUE_ENCLOSING_TYPE (fromval));
580 VALUE_EMBEDDED_OFFSET (val) = VALUE_EMBEDDED_OFFSET (fromval);
581 VALUE_POINTED_TO_OFFSET (val) = VALUE_POINTED_TO_OFFSET (fromval);
582 return val;
583
584 case lval_internalvar_component:
585 set_internalvar_component (VALUE_INTERNALVAR (toval),
586 VALUE_OFFSET (toval),
587 VALUE_BITPOS (toval),
588 VALUE_BITSIZE (toval),
589 fromval);
590 break;
591
592 case lval_memory:
593 {
594 char *dest_buffer;
595 CORE_ADDR changed_addr;
596 int changed_len;
597
598 if (VALUE_BITSIZE (toval))
599 {
600 char buffer[sizeof (LONGEST)];
601 /* We assume that the argument to read_memory is in units of
602 host chars. FIXME: Is that correct? */
603 changed_len = (VALUE_BITPOS (toval)
604 + VALUE_BITSIZE (toval)
605 + HOST_CHAR_BIT - 1)
606 / HOST_CHAR_BIT;
607
608 if (changed_len > (int) sizeof (LONGEST))
609 error ("Can't handle bitfields which don't fit in a %d bit word.",
610 sizeof (LONGEST) * HOST_CHAR_BIT);
611
612 read_memory (VALUE_ADDRESS (toval) + VALUE_OFFSET (toval),
613 buffer, changed_len);
614 modify_field (buffer, value_as_long (fromval),
615 VALUE_BITPOS (toval), VALUE_BITSIZE (toval));
616 changed_addr = VALUE_ADDRESS (toval) + VALUE_OFFSET (toval);
617 dest_buffer = buffer;
618 }
619 else if (use_buffer)
620 {
621 changed_addr = VALUE_ADDRESS (toval) + VALUE_OFFSET (toval);
622 changed_len = use_buffer;
623 dest_buffer = raw_buffer;
624 }
625 else
626 {
627 changed_addr = VALUE_ADDRESS (toval) + VALUE_OFFSET (toval);
628 changed_len = TYPE_LENGTH (type);
629 dest_buffer = VALUE_CONTENTS (fromval);
630 }
631
632 write_memory (changed_addr, dest_buffer, changed_len);
633 if (memory_changed_hook)
634 memory_changed_hook (changed_addr, changed_len);
635 }
636 break;
637
638 case lval_register:
639 if (VALUE_BITSIZE (toval))
640 {
641 char buffer[sizeof (LONGEST)];
642 int len =
643 REGISTER_RAW_SIZE (VALUE_REGNO (toval)) - VALUE_OFFSET (toval);
644
645 if (len > (int) sizeof (LONGEST))
646 error ("Can't handle bitfields in registers larger than %d bits.",
647 sizeof (LONGEST) * HOST_CHAR_BIT);
648
649 if (VALUE_BITPOS (toval) + VALUE_BITSIZE (toval)
650 > len * HOST_CHAR_BIT)
651 /* Getting this right would involve being very careful about
652 byte order. */
653 error ("Can't assign to bitfields that cross register "
654 "boundaries.");
655
656 read_register_bytes (VALUE_ADDRESS (toval) + VALUE_OFFSET (toval),
657 buffer, len);
658 modify_field (buffer, value_as_long (fromval),
659 VALUE_BITPOS (toval), VALUE_BITSIZE (toval));
660 write_register_bytes (VALUE_ADDRESS (toval) + VALUE_OFFSET (toval),
661 buffer, len);
662 }
663 else if (use_buffer)
664 write_register_bytes (VALUE_ADDRESS (toval) + VALUE_OFFSET (toval),
665 raw_buffer, use_buffer);
666 else
667 {
668 /* Do any conversion necessary when storing this type to more
669 than one register. */
670 #ifdef REGISTER_CONVERT_FROM_TYPE
671 memcpy (raw_buffer, VALUE_CONTENTS (fromval), TYPE_LENGTH (type));
672 REGISTER_CONVERT_FROM_TYPE (VALUE_REGNO (toval), type, raw_buffer);
673 write_register_bytes (VALUE_ADDRESS (toval) + VALUE_OFFSET (toval),
674 raw_buffer, TYPE_LENGTH (type));
675 #else
676 write_register_bytes (VALUE_ADDRESS (toval) + VALUE_OFFSET (toval),
677 VALUE_CONTENTS (fromval), TYPE_LENGTH (type));
678 #endif
679 }
680 /* Assigning to the stack pointer, frame pointer, and other
681 (architecture and calling convention specific) registers may
682 cause the frame cache to be out of date. We just do this
683 on all assignments to registers for simplicity; I doubt the slowdown
684 matters. */
685 reinit_frame_cache ();
686 break;
687
688 case lval_reg_frame_relative:
689 {
690 /* value is stored in a series of registers in the frame
691 specified by the structure. Copy that value out, modify
692 it, and copy it back in. */
693 int amount_to_copy = (VALUE_BITSIZE (toval) ? 1 : TYPE_LENGTH (type));
694 int reg_size = REGISTER_RAW_SIZE (VALUE_FRAME_REGNUM (toval));
695 int byte_offset = VALUE_OFFSET (toval) % reg_size;
696 int reg_offset = VALUE_OFFSET (toval) / reg_size;
697 int amount_copied;
698
699 /* Make the buffer large enough in all cases. */
700 char *buffer = (char *) alloca (amount_to_copy
701 + sizeof (LONGEST)
702 + MAX_REGISTER_RAW_SIZE);
703
704 int regno;
705 struct frame_info *frame;
706
707 /* Figure out which frame this is in currently. */
708 for (frame = get_current_frame ();
709 frame && FRAME_FP (frame) != VALUE_FRAME (toval);
710 frame = get_prev_frame (frame))
711 ;
712
713 if (!frame)
714 error ("Value being assigned to is no longer active.");
715
716 amount_to_copy += (reg_size - amount_to_copy % reg_size);
717
718 /* Copy it out. */
719 for ((regno = VALUE_FRAME_REGNUM (toval) + reg_offset,
720 amount_copied = 0);
721 amount_copied < amount_to_copy;
722 amount_copied += reg_size, regno++)
723 {
724 get_saved_register (buffer + amount_copied,
725 (int *) NULL, (CORE_ADDR *) NULL,
726 frame, regno, (enum lval_type *) NULL);
727 }
728
729 /* Modify what needs to be modified. */
730 if (VALUE_BITSIZE (toval))
731 modify_field (buffer + byte_offset,
732 value_as_long (fromval),
733 VALUE_BITPOS (toval), VALUE_BITSIZE (toval));
734 else if (use_buffer)
735 memcpy (buffer + byte_offset, raw_buffer, use_buffer);
736 else
737 memcpy (buffer + byte_offset, VALUE_CONTENTS (fromval),
738 TYPE_LENGTH (type));
739
740 /* Copy it back. */
741 for ((regno = VALUE_FRAME_REGNUM (toval) + reg_offset,
742 amount_copied = 0);
743 amount_copied < amount_to_copy;
744 amount_copied += reg_size, regno++)
745 {
746 enum lval_type lval;
747 CORE_ADDR addr;
748 int optim;
749
750 /* Just find out where to put it. */
751 get_saved_register ((char *) NULL,
752 &optim, &addr, frame, regno, &lval);
753
754 if (optim)
755 error ("Attempt to assign to a value that was optimized out.");
756 if (lval == lval_memory)
757 write_memory (addr, buffer + amount_copied, reg_size);
758 else if (lval == lval_register)
759 write_register_bytes (addr, buffer + amount_copied, reg_size);
760 else
761 error ("Attempt to assign to an unmodifiable value.");
762 }
763
764 if (register_changed_hook)
765 register_changed_hook (-1);
766 }
767 break;
768
769
770 default:
771 error ("Left operand of assignment is not an lvalue.");
772 }
773
774 /* If the field does not entirely fill a LONGEST, then zero the sign bits.
775 If the field is signed, and is negative, then sign extend. */
776 if ((VALUE_BITSIZE (toval) > 0)
777 && (VALUE_BITSIZE (toval) < 8 * (int) sizeof (LONGEST)))
778 {
779 LONGEST fieldval = value_as_long (fromval);
780 LONGEST valmask = (((ULONGEST) 1) << VALUE_BITSIZE (toval)) - 1;
781
782 fieldval &= valmask;
783 if (!TYPE_UNSIGNED (type) && (fieldval & (valmask ^ (valmask >> 1))))
784 fieldval |= ~valmask;
785
786 fromval = value_from_longest (type, fieldval);
787 }
788
789 val = value_copy (toval);
790 memcpy (VALUE_CONTENTS_RAW (val), VALUE_CONTENTS (fromval),
791 TYPE_LENGTH (type));
792 VALUE_TYPE (val) = type;
793 val = value_change_enclosing_type (val, VALUE_ENCLOSING_TYPE (fromval));
794 VALUE_EMBEDDED_OFFSET (val) = VALUE_EMBEDDED_OFFSET (fromval);
795 VALUE_POINTED_TO_OFFSET (val) = VALUE_POINTED_TO_OFFSET (fromval);
796
797 return val;
798 }
799
800 /* Extend a value VAL to COUNT repetitions of its type. */
801
802 struct value *
803 value_repeat (struct value *arg1, int count)
804 {
805 struct value *val;
806
807 if (VALUE_LVAL (arg1) != lval_memory)
808 error ("Only values in memory can be extended with '@'.");
809 if (count < 1)
810 error ("Invalid number %d of repetitions.", count);
811
812 val = allocate_repeat_value (VALUE_ENCLOSING_TYPE (arg1), count);
813
814 read_memory (VALUE_ADDRESS (arg1) + VALUE_OFFSET (arg1),
815 VALUE_CONTENTS_ALL_RAW (val),
816 TYPE_LENGTH (VALUE_ENCLOSING_TYPE (val)));
817 VALUE_LVAL (val) = lval_memory;
818 VALUE_ADDRESS (val) = VALUE_ADDRESS (arg1) + VALUE_OFFSET (arg1);
819
820 return val;
821 }
822
823 struct value *
824 value_of_variable (struct symbol *var, struct block *b)
825 {
826 struct value *val;
827 struct frame_info *frame = NULL;
828
829 if (!b)
830 frame = NULL; /* Use selected frame. */
831 else if (symbol_read_needs_frame (var))
832 {
833 frame = block_innermost_frame (b);
834 if (!frame)
835 {
836 if (BLOCK_FUNCTION (b)
837 && SYMBOL_SOURCE_NAME (BLOCK_FUNCTION (b)))
838 error ("No frame is currently executing in block %s.",
839 SYMBOL_SOURCE_NAME (BLOCK_FUNCTION (b)));
840 else
841 error ("No frame is currently executing in specified block");
842 }
843 }
844
845 val = read_var_value (var, frame);
846 if (!val)
847 error ("Address of symbol \"%s\" is unknown.", SYMBOL_SOURCE_NAME (var));
848
849 return val;
850 }
851
852 /* Given a value which is an array, return a value which is a pointer to its
853 first element, regardless of whether or not the array has a nonzero lower
854 bound.
855
856 FIXME: A previous comment here indicated that this routine should be
857 substracting the array's lower bound. It's not clear to me that this
858 is correct. Given an array subscripting operation, it would certainly
859 work to do the adjustment here, essentially computing:
860
861 (&array[0] - (lowerbound * sizeof array[0])) + (index * sizeof array[0])
862
863 However I believe a more appropriate and logical place to account for
864 the lower bound is to do so in value_subscript, essentially computing:
865
866 (&array[0] + ((index - lowerbound) * sizeof array[0]))
867
868 As further evidence consider what would happen with operations other
869 than array subscripting, where the caller would get back a value that
870 had an address somewhere before the actual first element of the array,
871 and the information about the lower bound would be lost because of
872 the coercion to pointer type.
873 */
874
875 struct value *
876 value_coerce_array (struct value *arg1)
877 {
878 register struct type *type = check_typedef (VALUE_TYPE (arg1));
879
880 if (VALUE_LVAL (arg1) != lval_memory)
881 error ("Attempt to take address of value not located in memory.");
882
883 return value_from_pointer (lookup_pointer_type (TYPE_TARGET_TYPE (type)),
884 (VALUE_ADDRESS (arg1) + VALUE_OFFSET (arg1)));
885 }
886
887 /* Given a value which is a function, return a value which is a pointer
888 to it. */
889
890 struct value *
891 value_coerce_function (struct value *arg1)
892 {
893 struct value *retval;
894
895 if (VALUE_LVAL (arg1) != lval_memory)
896 error ("Attempt to take address of value not located in memory.");
897
898 retval = value_from_pointer (lookup_pointer_type (VALUE_TYPE (arg1)),
899 (VALUE_ADDRESS (arg1) + VALUE_OFFSET (arg1)));
900 VALUE_BFD_SECTION (retval) = VALUE_BFD_SECTION (arg1);
901 return retval;
902 }
903
904 /* Return a pointer value for the object for which ARG1 is the contents. */
905
906 struct value *
907 value_addr (struct value *arg1)
908 {
909 struct value *arg2;
910
911 struct type *type = check_typedef (VALUE_TYPE (arg1));
912 if (TYPE_CODE (type) == TYPE_CODE_REF)
913 {
914 /* Copy the value, but change the type from (T&) to (T*).
915 We keep the same location information, which is efficient,
916 and allows &(&X) to get the location containing the reference. */
917 arg2 = value_copy (arg1);
918 VALUE_TYPE (arg2) = lookup_pointer_type (TYPE_TARGET_TYPE (type));
919 return arg2;
920 }
921 if (TYPE_CODE (type) == TYPE_CODE_FUNC)
922 return value_coerce_function (arg1);
923
924 if (VALUE_LVAL (arg1) != lval_memory)
925 error ("Attempt to take address of value not located in memory.");
926
927 /* Get target memory address */
928 arg2 = value_from_pointer (lookup_pointer_type (VALUE_TYPE (arg1)),
929 (VALUE_ADDRESS (arg1)
930 + VALUE_OFFSET (arg1)
931 + VALUE_EMBEDDED_OFFSET (arg1)));
932
933 /* This may be a pointer to a base subobject; so remember the
934 full derived object's type ... */
935 arg2 = value_change_enclosing_type (arg2, lookup_pointer_type (VALUE_ENCLOSING_TYPE (arg1)));
936 /* ... and also the relative position of the subobject in the full object */
937 VALUE_POINTED_TO_OFFSET (arg2) = VALUE_EMBEDDED_OFFSET (arg1);
938 VALUE_BFD_SECTION (arg2) = VALUE_BFD_SECTION (arg1);
939 return arg2;
940 }
941
942 /* Given a value of a pointer type, apply the C unary * operator to it. */
943
944 struct value *
945 value_ind (struct value *arg1)
946 {
947 struct type *base_type;
948 struct value *arg2;
949
950 COERCE_ARRAY (arg1);
951
952 base_type = check_typedef (VALUE_TYPE (arg1));
953
954 if (TYPE_CODE (base_type) == TYPE_CODE_MEMBER)
955 error ("not implemented: member types in value_ind");
956
957 /* Allow * on an integer so we can cast it to whatever we want.
958 This returns an int, which seems like the most C-like thing
959 to do. "long long" variables are rare enough that
960 BUILTIN_TYPE_LONGEST would seem to be a mistake. */
961 if (TYPE_CODE (base_type) == TYPE_CODE_INT)
962 return value_at (builtin_type_int,
963 (CORE_ADDR) value_as_long (arg1),
964 VALUE_BFD_SECTION (arg1));
965 else if (TYPE_CODE (base_type) == TYPE_CODE_PTR)
966 {
967 struct type *enc_type;
968 /* We may be pointing to something embedded in a larger object */
969 /* Get the real type of the enclosing object */
970 enc_type = check_typedef (VALUE_ENCLOSING_TYPE (arg1));
971 enc_type = TYPE_TARGET_TYPE (enc_type);
972 /* Retrieve the enclosing object pointed to */
973 arg2 = value_at_lazy (enc_type,
974 value_as_address (arg1) - VALUE_POINTED_TO_OFFSET (arg1),
975 VALUE_BFD_SECTION (arg1));
976 /* Re-adjust type */
977 VALUE_TYPE (arg2) = TYPE_TARGET_TYPE (base_type);
978 /* Add embedding info */
979 arg2 = value_change_enclosing_type (arg2, enc_type);
980 VALUE_EMBEDDED_OFFSET (arg2) = VALUE_POINTED_TO_OFFSET (arg1);
981
982 /* We may be pointing to an object of some derived type */
983 arg2 = value_full_object (arg2, NULL, 0, 0, 0);
984 return arg2;
985 }
986
987 error ("Attempt to take contents of a non-pointer value.");
988 return 0; /* For lint -- never reached */
989 }
990 \f
991 /* Pushing small parts of stack frames. */
992
993 /* Push one word (the size of object that a register holds). */
994
995 CORE_ADDR
996 push_word (CORE_ADDR sp, ULONGEST word)
997 {
998 register int len = REGISTER_SIZE;
999 char *buffer = alloca (MAX_REGISTER_RAW_SIZE);
1000
1001 store_unsigned_integer (buffer, len, word);
1002 if (INNER_THAN (1, 2))
1003 {
1004 /* stack grows downward */
1005 sp -= len;
1006 write_memory (sp, buffer, len);
1007 }
1008 else
1009 {
1010 /* stack grows upward */
1011 write_memory (sp, buffer, len);
1012 sp += len;
1013 }
1014
1015 return sp;
1016 }
1017
1018 /* Push LEN bytes with data at BUFFER. */
1019
1020 CORE_ADDR
1021 push_bytes (CORE_ADDR sp, char *buffer, int len)
1022 {
1023 if (INNER_THAN (1, 2))
1024 {
1025 /* stack grows downward */
1026 sp -= len;
1027 write_memory (sp, buffer, len);
1028 }
1029 else
1030 {
1031 /* stack grows upward */
1032 write_memory (sp, buffer, len);
1033 sp += len;
1034 }
1035
1036 return sp;
1037 }
1038
1039 #ifndef PARM_BOUNDARY
1040 #define PARM_BOUNDARY (0)
1041 #endif
1042
1043 /* Push onto the stack the specified value VALUE. Pad it correctly for
1044 it to be an argument to a function. */
1045
1046 static CORE_ADDR
1047 value_push (register CORE_ADDR sp, struct value *arg)
1048 {
1049 register int len = TYPE_LENGTH (VALUE_ENCLOSING_TYPE (arg));
1050 register int container_len = len;
1051 register int offset;
1052
1053 /* How big is the container we're going to put this value in? */
1054 if (PARM_BOUNDARY)
1055 container_len = ((len + PARM_BOUNDARY / TARGET_CHAR_BIT - 1)
1056 & ~(PARM_BOUNDARY / TARGET_CHAR_BIT - 1));
1057
1058 /* Are we going to put it at the high or low end of the container? */
1059 if (TARGET_BYTE_ORDER == BIG_ENDIAN)
1060 offset = container_len - len;
1061 else
1062 offset = 0;
1063
1064 if (INNER_THAN (1, 2))
1065 {
1066 /* stack grows downward */
1067 sp -= container_len;
1068 write_memory (sp + offset, VALUE_CONTENTS_ALL (arg), len);
1069 }
1070 else
1071 {
1072 /* stack grows upward */
1073 write_memory (sp + offset, VALUE_CONTENTS_ALL (arg), len);
1074 sp += container_len;
1075 }
1076
1077 return sp;
1078 }
1079
1080 #ifndef PUSH_ARGUMENTS
1081 #define PUSH_ARGUMENTS default_push_arguments
1082 #endif
1083
1084 CORE_ADDR
1085 default_push_arguments (int nargs, struct value **args, CORE_ADDR sp,
1086 int struct_return, CORE_ADDR struct_addr)
1087 {
1088 /* ASSERT ( !struct_return); */
1089 int i;
1090 for (i = nargs - 1; i >= 0; i--)
1091 sp = value_push (sp, args[i]);
1092 return sp;
1093 }
1094
1095
1096 /* Functions to use for the COERCE_FLOAT_TO_DOUBLE gdbarch method.
1097
1098 How you should pass arguments to a function depends on whether it
1099 was defined in K&R style or prototype style. If you define a
1100 function using the K&R syntax that takes a `float' argument, then
1101 callers must pass that argument as a `double'. If you define the
1102 function using the prototype syntax, then you must pass the
1103 argument as a `float', with no promotion.
1104
1105 Unfortunately, on certain older platforms, the debug info doesn't
1106 indicate reliably how each function was defined. A function type's
1107 TYPE_FLAG_PROTOTYPED flag may be clear, even if the function was
1108 defined in prototype style. When calling a function whose
1109 TYPE_FLAG_PROTOTYPED flag is clear, GDB consults the
1110 COERCE_FLOAT_TO_DOUBLE gdbarch method to decide what to do.
1111
1112 For modern targets, it is proper to assume that, if the prototype
1113 flag is clear, that can be trusted: `float' arguments should be
1114 promoted to `double'. You should register the function
1115 `standard_coerce_float_to_double' to get this behavior.
1116
1117 For some older targets, if the prototype flag is clear, that
1118 doesn't tell us anything. So we guess that, if we don't have a
1119 type for the formal parameter (i.e., the first argument to
1120 COERCE_FLOAT_TO_DOUBLE is null), then we should promote it;
1121 otherwise, we should leave it alone. The function
1122 `default_coerce_float_to_double' provides this behavior; it is the
1123 default value, for compatibility with older configurations. */
1124 int
1125 default_coerce_float_to_double (struct type *formal, struct type *actual)
1126 {
1127 return formal == NULL;
1128 }
1129
1130
1131 int
1132 standard_coerce_float_to_double (struct type *formal, struct type *actual)
1133 {
1134 return 1;
1135 }
1136
1137
1138 /* Perform the standard coercions that are specified
1139 for arguments to be passed to C functions.
1140
1141 If PARAM_TYPE is non-NULL, it is the expected parameter type.
1142 IS_PROTOTYPED is non-zero if the function declaration is prototyped. */
1143
1144 static struct value *
1145 value_arg_coerce (struct value *arg, struct type *param_type, int is_prototyped)
1146 {
1147 register struct type *arg_type = check_typedef (VALUE_TYPE (arg));
1148 register struct type *type
1149 = param_type ? check_typedef (param_type) : arg_type;
1150
1151 switch (TYPE_CODE (type))
1152 {
1153 case TYPE_CODE_REF:
1154 if (TYPE_CODE (arg_type) != TYPE_CODE_REF)
1155 {
1156 arg = value_addr (arg);
1157 VALUE_TYPE (arg) = param_type;
1158 return arg;
1159 }
1160 break;
1161 case TYPE_CODE_INT:
1162 case TYPE_CODE_CHAR:
1163 case TYPE_CODE_BOOL:
1164 case TYPE_CODE_ENUM:
1165 /* If we don't have a prototype, coerce to integer type if necessary. */
1166 if (!is_prototyped)
1167 {
1168 if (TYPE_LENGTH (type) < TYPE_LENGTH (builtin_type_int))
1169 type = builtin_type_int;
1170 }
1171 /* Currently all target ABIs require at least the width of an integer
1172 type for an argument. We may have to conditionalize the following
1173 type coercion for future targets. */
1174 if (TYPE_LENGTH (type) < TYPE_LENGTH (builtin_type_int))
1175 type = builtin_type_int;
1176 break;
1177 case TYPE_CODE_FLT:
1178 /* FIXME: We should always convert floats to doubles in the
1179 non-prototyped case. As many debugging formats include
1180 no information about prototyping, we have to live with
1181 COERCE_FLOAT_TO_DOUBLE for now. */
1182 if (!is_prototyped && COERCE_FLOAT_TO_DOUBLE (param_type, arg_type))
1183 {
1184 if (TYPE_LENGTH (type) < TYPE_LENGTH (builtin_type_double))
1185 type = builtin_type_double;
1186 else if (TYPE_LENGTH (type) > TYPE_LENGTH (builtin_type_double))
1187 type = builtin_type_long_double;
1188 }
1189 break;
1190 case TYPE_CODE_FUNC:
1191 type = lookup_pointer_type (type);
1192 break;
1193 case TYPE_CODE_ARRAY:
1194 if (current_language->c_style_arrays)
1195 type = lookup_pointer_type (TYPE_TARGET_TYPE (type));
1196 break;
1197 case TYPE_CODE_UNDEF:
1198 case TYPE_CODE_PTR:
1199 case TYPE_CODE_STRUCT:
1200 case TYPE_CODE_UNION:
1201 case TYPE_CODE_VOID:
1202 case TYPE_CODE_SET:
1203 case TYPE_CODE_RANGE:
1204 case TYPE_CODE_STRING:
1205 case TYPE_CODE_BITSTRING:
1206 case TYPE_CODE_ERROR:
1207 case TYPE_CODE_MEMBER:
1208 case TYPE_CODE_METHOD:
1209 case TYPE_CODE_COMPLEX:
1210 default:
1211 break;
1212 }
1213
1214 return value_cast (type, arg);
1215 }
1216
1217 /* Determine a function's address and its return type from its value.
1218 Calls error() if the function is not valid for calling. */
1219
1220 static CORE_ADDR
1221 find_function_addr (struct value *function, struct type **retval_type)
1222 {
1223 register struct type *ftype = check_typedef (VALUE_TYPE (function));
1224 register enum type_code code = TYPE_CODE (ftype);
1225 struct type *value_type;
1226 CORE_ADDR funaddr;
1227
1228 /* If it's a member function, just look at the function
1229 part of it. */
1230
1231 /* Determine address to call. */
1232 if (code == TYPE_CODE_FUNC || code == TYPE_CODE_METHOD)
1233 {
1234 funaddr = VALUE_ADDRESS (function);
1235 value_type = TYPE_TARGET_TYPE (ftype);
1236 }
1237 else if (code == TYPE_CODE_PTR)
1238 {
1239 funaddr = value_as_address (function);
1240 ftype = check_typedef (TYPE_TARGET_TYPE (ftype));
1241 if (TYPE_CODE (ftype) == TYPE_CODE_FUNC
1242 || TYPE_CODE (ftype) == TYPE_CODE_METHOD)
1243 {
1244 funaddr = CONVERT_FROM_FUNC_PTR_ADDR (funaddr);
1245 value_type = TYPE_TARGET_TYPE (ftype);
1246 }
1247 else
1248 value_type = builtin_type_int;
1249 }
1250 else if (code == TYPE_CODE_INT)
1251 {
1252 /* Handle the case of functions lacking debugging info.
1253 Their values are characters since their addresses are char */
1254 if (TYPE_LENGTH (ftype) == 1)
1255 funaddr = value_as_address (value_addr (function));
1256 else
1257 /* Handle integer used as address of a function. */
1258 funaddr = (CORE_ADDR) value_as_long (function);
1259
1260 value_type = builtin_type_int;
1261 }
1262 else
1263 error ("Invalid data type for function to be called.");
1264
1265 *retval_type = value_type;
1266 return funaddr;
1267 }
1268
1269 /* All this stuff with a dummy frame may seem unnecessarily complicated
1270 (why not just save registers in GDB?). The purpose of pushing a dummy
1271 frame which looks just like a real frame is so that if you call a
1272 function and then hit a breakpoint (get a signal, etc), "backtrace"
1273 will look right. Whether the backtrace needs to actually show the
1274 stack at the time the inferior function was called is debatable, but
1275 it certainly needs to not display garbage. So if you are contemplating
1276 making dummy frames be different from normal frames, consider that. */
1277
1278 /* Perform a function call in the inferior.
1279 ARGS is a vector of values of arguments (NARGS of them).
1280 FUNCTION is a value, the function to be called.
1281 Returns a value representing what the function returned.
1282 May fail to return, if a breakpoint or signal is hit
1283 during the execution of the function.
1284
1285 ARGS is modified to contain coerced values. */
1286
1287 static struct value *
1288 hand_function_call (struct value *function, int nargs, struct value **args)
1289 {
1290 register CORE_ADDR sp;
1291 register int i;
1292 int rc;
1293 CORE_ADDR start_sp;
1294 /* CALL_DUMMY is an array of words (REGISTER_SIZE), but each word
1295 is in host byte order. Before calling FIX_CALL_DUMMY, we byteswap it
1296 and remove any extra bytes which might exist because ULONGEST is
1297 bigger than REGISTER_SIZE.
1298
1299 NOTE: This is pretty wierd, as the call dummy is actually a
1300 sequence of instructions. But CISC machines will have
1301 to pack the instructions into REGISTER_SIZE units (and
1302 so will RISC machines for which INSTRUCTION_SIZE is not
1303 REGISTER_SIZE).
1304
1305 NOTE: This is pretty stupid. CALL_DUMMY should be in strict
1306 target byte order. */
1307
1308 static ULONGEST *dummy;
1309 int sizeof_dummy1;
1310 char *dummy1;
1311 CORE_ADDR old_sp;
1312 struct type *value_type;
1313 unsigned char struct_return;
1314 CORE_ADDR struct_addr = 0;
1315 struct inferior_status *inf_status;
1316 struct cleanup *old_chain;
1317 CORE_ADDR funaddr;
1318 int using_gcc; /* Set to version of gcc in use, or zero if not gcc */
1319 CORE_ADDR real_pc;
1320 struct type *param_type = NULL;
1321 struct type *ftype = check_typedef (SYMBOL_TYPE (function));
1322 int n_method_args = 0;
1323
1324 dummy = alloca (SIZEOF_CALL_DUMMY_WORDS);
1325 sizeof_dummy1 = REGISTER_SIZE * SIZEOF_CALL_DUMMY_WORDS / sizeof (ULONGEST);
1326 dummy1 = alloca (sizeof_dummy1);
1327 memcpy (dummy, CALL_DUMMY_WORDS, SIZEOF_CALL_DUMMY_WORDS);
1328
1329 if (!target_has_execution)
1330 noprocess ();
1331
1332 inf_status = save_inferior_status (1);
1333 old_chain = make_cleanup_restore_inferior_status (inf_status);
1334
1335 /* PUSH_DUMMY_FRAME is responsible for saving the inferior registers
1336 (and POP_FRAME for restoring them). (At least on most machines)
1337 they are saved on the stack in the inferior. */
1338 PUSH_DUMMY_FRAME;
1339
1340 old_sp = sp = read_sp ();
1341
1342 if (INNER_THAN (1, 2))
1343 {
1344 /* Stack grows down */
1345 sp -= sizeof_dummy1;
1346 start_sp = sp;
1347 }
1348 else
1349 {
1350 /* Stack grows up */
1351 start_sp = sp;
1352 sp += sizeof_dummy1;
1353 }
1354
1355 funaddr = find_function_addr (function, &value_type);
1356 CHECK_TYPEDEF (value_type);
1357
1358 {
1359 struct block *b = block_for_pc (funaddr);
1360 /* If compiled without -g, assume GCC 2. */
1361 using_gcc = (b == NULL ? 2 : BLOCK_GCC_COMPILED (b));
1362 }
1363
1364 /* Are we returning a value using a structure return or a normal
1365 value return? */
1366
1367 struct_return = using_struct_return (function, funaddr, value_type,
1368 using_gcc);
1369
1370 /* Create a call sequence customized for this function
1371 and the number of arguments for it. */
1372 for (i = 0; i < (int) (SIZEOF_CALL_DUMMY_WORDS / sizeof (dummy[0])); i++)
1373 store_unsigned_integer (&dummy1[i * REGISTER_SIZE],
1374 REGISTER_SIZE,
1375 (ULONGEST) dummy[i]);
1376
1377 #ifdef GDB_TARGET_IS_HPPA
1378 real_pc = FIX_CALL_DUMMY (dummy1, start_sp, funaddr, nargs, args,
1379 value_type, using_gcc);
1380 #else
1381 FIX_CALL_DUMMY (dummy1, start_sp, funaddr, nargs, args,
1382 value_type, using_gcc);
1383 real_pc = start_sp;
1384 #endif
1385
1386 if (CALL_DUMMY_LOCATION == ON_STACK)
1387 {
1388 write_memory (start_sp, (char *) dummy1, sizeof_dummy1);
1389 }
1390
1391 if (CALL_DUMMY_LOCATION == BEFORE_TEXT_END)
1392 {
1393 /* Convex Unix prohibits executing in the stack segment. */
1394 /* Hope there is empty room at the top of the text segment. */
1395 extern CORE_ADDR text_end;
1396 static int checked = 0;
1397 if (!checked)
1398 for (start_sp = text_end - sizeof_dummy1; start_sp < text_end; ++start_sp)
1399 if (read_memory_integer (start_sp, 1) != 0)
1400 error ("text segment full -- no place to put call");
1401 checked = 1;
1402 sp = old_sp;
1403 real_pc = text_end - sizeof_dummy1;
1404 write_memory (real_pc, (char *) dummy1, sizeof_dummy1);
1405 }
1406
1407 if (CALL_DUMMY_LOCATION == AFTER_TEXT_END)
1408 {
1409 extern CORE_ADDR text_end;
1410 int errcode;
1411 sp = old_sp;
1412 real_pc = text_end;
1413 errcode = target_write_memory (real_pc, (char *) dummy1, sizeof_dummy1);
1414 if (errcode != 0)
1415 error ("Cannot write text segment -- call_function failed");
1416 }
1417
1418 if (CALL_DUMMY_LOCATION == AT_ENTRY_POINT)
1419 {
1420 real_pc = funaddr;
1421 }
1422
1423 #ifdef lint
1424 sp = old_sp; /* It really is used, for some ifdef's... */
1425 #endif
1426
1427 if (TYPE_CODE (ftype) == TYPE_CODE_METHOD)
1428 {
1429 i = 0;
1430 while (TYPE_CODE (TYPE_ARG_TYPES (ftype)[i]) != TYPE_CODE_VOID)
1431 i++;
1432 n_method_args = i;
1433 if (nargs < i)
1434 error ("too few arguments in method call");
1435 }
1436 else if (nargs < TYPE_NFIELDS (ftype))
1437 error ("too few arguments in function call");
1438
1439 for (i = nargs - 1; i >= 0; i--)
1440 {
1441 /* Assume that methods are always prototyped, unless they are off the
1442 end (which we should only be allowing if there is a ``...'').
1443 FIXME. */
1444 if (TYPE_CODE (ftype) == TYPE_CODE_METHOD)
1445 {
1446 if (i < n_method_args)
1447 args[i] = value_arg_coerce (args[i], TYPE_ARG_TYPES (ftype)[i], 1);
1448 else
1449 args[i] = value_arg_coerce (args[i], NULL, 0);
1450 }
1451
1452 /* If we're off the end of the known arguments, do the standard
1453 promotions. FIXME: if we had a prototype, this should only
1454 be allowed if ... were present. */
1455 if (i >= TYPE_NFIELDS (ftype))
1456 args[i] = value_arg_coerce (args[i], NULL, 0);
1457
1458 else
1459 {
1460 param_type = TYPE_FIELD_TYPE (ftype, i);
1461 args[i] = value_arg_coerce (args[i], param_type, TYPE_PROTOTYPED (ftype));
1462 }
1463
1464 /*elz: this code is to handle the case in which the function to be called
1465 has a pointer to function as parameter and the corresponding actual argument
1466 is the address of a function and not a pointer to function variable.
1467 In aCC compiled code, the calls through pointers to functions (in the body
1468 of the function called by hand) are made via $$dyncall_external which
1469 requires some registers setting, this is taken care of if we call
1470 via a function pointer variable, but not via a function address.
1471 In cc this is not a problem. */
1472
1473 if (using_gcc == 0)
1474 if (param_type)
1475 /* if this parameter is a pointer to function */
1476 if (TYPE_CODE (param_type) == TYPE_CODE_PTR)
1477 if (TYPE_CODE (param_type->target_type) == TYPE_CODE_FUNC)
1478 /* elz: FIXME here should go the test about the compiler used
1479 to compile the target. We want to issue the error
1480 message only if the compiler used was HP's aCC.
1481 If we used HP's cc, then there is no problem and no need
1482 to return at this point */
1483 if (using_gcc == 0) /* && compiler == aCC */
1484 /* go see if the actual parameter is a variable of type
1485 pointer to function or just a function */
1486 if (args[i]->lval == not_lval)
1487 {
1488 char *arg_name;
1489 if (find_pc_partial_function ((CORE_ADDR) args[i]->aligner.contents[0], &arg_name, NULL, NULL))
1490 error ("\
1491 You cannot use function <%s> as argument. \n\
1492 You must use a pointer to function type variable. Command ignored.", arg_name);
1493 }
1494 }
1495
1496 if (REG_STRUCT_HAS_ADDR_P ())
1497 {
1498 /* This is a machine like the sparc, where we may need to pass a
1499 pointer to the structure, not the structure itself. */
1500 for (i = nargs - 1; i >= 0; i--)
1501 {
1502 struct type *arg_type = check_typedef (VALUE_TYPE (args[i]));
1503 if ((TYPE_CODE (arg_type) == TYPE_CODE_STRUCT
1504 || TYPE_CODE (arg_type) == TYPE_CODE_UNION
1505 || TYPE_CODE (arg_type) == TYPE_CODE_ARRAY
1506 || TYPE_CODE (arg_type) == TYPE_CODE_STRING
1507 || TYPE_CODE (arg_type) == TYPE_CODE_BITSTRING
1508 || TYPE_CODE (arg_type) == TYPE_CODE_SET
1509 || (TYPE_CODE (arg_type) == TYPE_CODE_FLT
1510 && TYPE_LENGTH (arg_type) > 8)
1511 )
1512 && REG_STRUCT_HAS_ADDR (using_gcc, arg_type))
1513 {
1514 CORE_ADDR addr;
1515 int len; /* = TYPE_LENGTH (arg_type); */
1516 int aligned_len;
1517 arg_type = check_typedef (VALUE_ENCLOSING_TYPE (args[i]));
1518 len = TYPE_LENGTH (arg_type);
1519
1520 if (STACK_ALIGN_P ())
1521 /* MVS 11/22/96: I think at least some of this
1522 stack_align code is really broken. Better to let
1523 PUSH_ARGUMENTS adjust the stack in a target-defined
1524 manner. */
1525 aligned_len = STACK_ALIGN (len);
1526 else
1527 aligned_len = len;
1528 if (INNER_THAN (1, 2))
1529 {
1530 /* stack grows downward */
1531 sp -= aligned_len;
1532 /* ... so the address of the thing we push is the
1533 stack pointer after we push it. */
1534 addr = sp;
1535 }
1536 else
1537 {
1538 /* The stack grows up, so the address of the thing
1539 we push is the stack pointer before we push it. */
1540 addr = sp;
1541 sp += aligned_len;
1542 }
1543 /* Push the structure. */
1544 write_memory (addr, VALUE_CONTENTS_ALL (args[i]), len);
1545 /* The value we're going to pass is the address of the
1546 thing we just pushed. */
1547 /*args[i] = value_from_longest (lookup_pointer_type (value_type),
1548 (LONGEST) addr); */
1549 args[i] = value_from_pointer (lookup_pointer_type (arg_type),
1550 addr);
1551 }
1552 }
1553 }
1554
1555
1556 /* Reserve space for the return structure to be written on the
1557 stack, if necessary */
1558
1559 if (struct_return)
1560 {
1561 int len = TYPE_LENGTH (value_type);
1562 if (STACK_ALIGN_P ())
1563 /* MVS 11/22/96: I think at least some of this stack_align
1564 code is really broken. Better to let PUSH_ARGUMENTS adjust
1565 the stack in a target-defined manner. */
1566 len = STACK_ALIGN (len);
1567 if (INNER_THAN (1, 2))
1568 {
1569 /* stack grows downward */
1570 sp -= len;
1571 struct_addr = sp;
1572 }
1573 else
1574 {
1575 /* stack grows upward */
1576 struct_addr = sp;
1577 sp += len;
1578 }
1579 }
1580
1581 /* elz: on HPPA no need for this extra alignment, maybe it is needed
1582 on other architectures. This is because all the alignment is
1583 taken care of in the above code (ifdef REG_STRUCT_HAS_ADDR) and
1584 in hppa_push_arguments */
1585 if (EXTRA_STACK_ALIGNMENT_NEEDED)
1586 {
1587 /* MVS 11/22/96: I think at least some of this stack_align code
1588 is really broken. Better to let PUSH_ARGUMENTS adjust the
1589 stack in a target-defined manner. */
1590 if (STACK_ALIGN_P () && INNER_THAN (1, 2))
1591 {
1592 /* If stack grows down, we must leave a hole at the top. */
1593 int len = 0;
1594
1595 for (i = nargs - 1; i >= 0; i--)
1596 len += TYPE_LENGTH (VALUE_ENCLOSING_TYPE (args[i]));
1597 if (CALL_DUMMY_STACK_ADJUST_P)
1598 len += CALL_DUMMY_STACK_ADJUST;
1599 sp -= STACK_ALIGN (len) - len;
1600 }
1601 }
1602
1603 sp = PUSH_ARGUMENTS (nargs, args, sp, struct_return, struct_addr);
1604
1605 if (PUSH_RETURN_ADDRESS_P ())
1606 /* for targets that use no CALL_DUMMY */
1607 /* There are a number of targets now which actually don't write
1608 any CALL_DUMMY instructions into the target, but instead just
1609 save the machine state, push the arguments, and jump directly
1610 to the callee function. Since this doesn't actually involve
1611 executing a JSR/BSR instruction, the return address must be set
1612 up by hand, either by pushing onto the stack or copying into a
1613 return-address register as appropriate. Formerly this has been
1614 done in PUSH_ARGUMENTS, but that's overloading its
1615 functionality a bit, so I'm making it explicit to do it here. */
1616 sp = PUSH_RETURN_ADDRESS (real_pc, sp);
1617
1618 if (STACK_ALIGN_P () && !INNER_THAN (1, 2))
1619 {
1620 /* If stack grows up, we must leave a hole at the bottom, note
1621 that sp already has been advanced for the arguments! */
1622 if (CALL_DUMMY_STACK_ADJUST_P)
1623 sp += CALL_DUMMY_STACK_ADJUST;
1624 sp = STACK_ALIGN (sp);
1625 }
1626
1627 /* XXX This seems wrong. For stacks that grow down we shouldn't do
1628 anything here! */
1629 /* MVS 11/22/96: I think at least some of this stack_align code is
1630 really broken. Better to let PUSH_ARGUMENTS adjust the stack in
1631 a target-defined manner. */
1632 if (CALL_DUMMY_STACK_ADJUST_P)
1633 if (INNER_THAN (1, 2))
1634 {
1635 /* stack grows downward */
1636 sp -= CALL_DUMMY_STACK_ADJUST;
1637 }
1638
1639 /* Store the address at which the structure is supposed to be
1640 written. Note that this (and the code which reserved the space
1641 above) assumes that gcc was used to compile this function. Since
1642 it doesn't cost us anything but space and if the function is pcc
1643 it will ignore this value, we will make that assumption.
1644
1645 Also note that on some machines (like the sparc) pcc uses a
1646 convention like gcc's. */
1647
1648 if (struct_return)
1649 STORE_STRUCT_RETURN (struct_addr, sp);
1650
1651 /* Write the stack pointer. This is here because the statements above
1652 might fool with it. On SPARC, this write also stores the register
1653 window into the right place in the new stack frame, which otherwise
1654 wouldn't happen. (See store_inferior_registers in sparc-nat.c.) */
1655 write_sp (sp);
1656
1657 if (SAVE_DUMMY_FRAME_TOS_P ())
1658 SAVE_DUMMY_FRAME_TOS (sp);
1659
1660 {
1661 char *retbuf = (char*) alloca (REGISTER_BYTES);
1662 char *name;
1663 struct symbol *symbol;
1664
1665 name = NULL;
1666 symbol = find_pc_function (funaddr);
1667 if (symbol)
1668 {
1669 name = SYMBOL_SOURCE_NAME (symbol);
1670 }
1671 else
1672 {
1673 /* Try the minimal symbols. */
1674 struct minimal_symbol *msymbol = lookup_minimal_symbol_by_pc (funaddr);
1675
1676 if (msymbol)
1677 {
1678 name = SYMBOL_SOURCE_NAME (msymbol);
1679 }
1680 }
1681 if (name == NULL)
1682 {
1683 char format[80];
1684 sprintf (format, "at %s", local_hex_format ());
1685 name = alloca (80);
1686 /* FIXME-32x64: assumes funaddr fits in a long. */
1687 sprintf (name, format, (unsigned long) funaddr);
1688 }
1689
1690 /* Execute the stack dummy routine, calling FUNCTION.
1691 When it is done, discard the empty frame
1692 after storing the contents of all regs into retbuf. */
1693 rc = run_stack_dummy (real_pc + CALL_DUMMY_START_OFFSET, retbuf);
1694
1695 if (rc == 1)
1696 {
1697 /* We stopped inside the FUNCTION because of a random signal.
1698 Further execution of the FUNCTION is not allowed. */
1699
1700 if (unwind_on_signal_p)
1701 {
1702 /* The user wants the context restored. */
1703
1704 /* We must get back to the frame we were before the dummy call. */
1705 POP_FRAME;
1706
1707 /* FIXME: Insert a bunch of wrap_here; name can be very long if it's
1708 a C++ name with arguments and stuff. */
1709 error ("\
1710 The program being debugged was signaled while in a function called from GDB.\n\
1711 GDB has restored the context to what it was before the call.\n\
1712 To change this behavior use \"set unwindonsignal off\"\n\
1713 Evaluation of the expression containing the function (%s) will be abandoned.",
1714 name);
1715 }
1716 else
1717 {
1718 /* The user wants to stay in the frame where we stopped (default).*/
1719
1720 /* If we did the cleanups, we would print a spurious error
1721 message (Unable to restore previously selected frame),
1722 would write the registers from the inf_status (which is
1723 wrong), and would do other wrong things. */
1724 discard_cleanups (old_chain);
1725 discard_inferior_status (inf_status);
1726
1727 /* FIXME: Insert a bunch of wrap_here; name can be very long if it's
1728 a C++ name with arguments and stuff. */
1729 error ("\
1730 The program being debugged was signaled while in a function called from GDB.\n\
1731 GDB remains in the frame where the signal was received.\n\
1732 To change this behavior use \"set unwindonsignal on\"\n\
1733 Evaluation of the expression containing the function (%s) will be abandoned.",
1734 name);
1735 }
1736 }
1737
1738 if (rc == 2)
1739 {
1740 /* We hit a breakpoint inside the FUNCTION. */
1741
1742 /* If we did the cleanups, we would print a spurious error
1743 message (Unable to restore previously selected frame),
1744 would write the registers from the inf_status (which is
1745 wrong), and would do other wrong things. */
1746 discard_cleanups (old_chain);
1747 discard_inferior_status (inf_status);
1748
1749 /* The following error message used to say "The expression
1750 which contained the function call has been discarded." It
1751 is a hard concept to explain in a few words. Ideally, GDB
1752 would be able to resume evaluation of the expression when
1753 the function finally is done executing. Perhaps someday
1754 this will be implemented (it would not be easy). */
1755
1756 /* FIXME: Insert a bunch of wrap_here; name can be very long if it's
1757 a C++ name with arguments and stuff. */
1758 error ("\
1759 The program being debugged stopped while in a function called from GDB.\n\
1760 When the function (%s) is done executing, GDB will silently\n\
1761 stop (instead of continuing to evaluate the expression containing\n\
1762 the function call).", name);
1763 }
1764
1765 /* If we get here the called FUNCTION run to completion. */
1766 do_cleanups (old_chain);
1767
1768 /* Figure out the value returned by the function. */
1769 /* elz: I defined this new macro for the hppa architecture only.
1770 this gives us a way to get the value returned by the function from the stack,
1771 at the same address we told the function to put it.
1772 We cannot assume on the pa that r28 still contains the address of the returned
1773 structure. Usually this will be overwritten by the callee.
1774 I don't know about other architectures, so I defined this macro
1775 */
1776
1777 #ifdef VALUE_RETURNED_FROM_STACK
1778 if (struct_return)
1779 return (struct value *) VALUE_RETURNED_FROM_STACK (value_type, struct_addr);
1780 #endif
1781
1782 return value_being_returned (value_type, retbuf, struct_return);
1783 }
1784 }
1785
1786 struct value *
1787 call_function_by_hand (struct value *function, int nargs, struct value **args)
1788 {
1789 if (CALL_DUMMY_P)
1790 {
1791 return hand_function_call (function, nargs, args);
1792 }
1793 else
1794 {
1795 error ("Cannot invoke functions on this machine.");
1796 }
1797 }
1798 \f
1799
1800
1801 /* Create a value for an array by allocating space in the inferior, copying
1802 the data into that space, and then setting up an array value.
1803
1804 The array bounds are set from LOWBOUND and HIGHBOUND, and the array is
1805 populated from the values passed in ELEMVEC.
1806
1807 The element type of the array is inherited from the type of the
1808 first element, and all elements must have the same size (though we
1809 don't currently enforce any restriction on their types). */
1810
1811 struct value *
1812 value_array (int lowbound, int highbound, struct value **elemvec)
1813 {
1814 int nelem;
1815 int idx;
1816 unsigned int typelength;
1817 struct value *val;
1818 struct type *rangetype;
1819 struct type *arraytype;
1820 CORE_ADDR addr;
1821
1822 /* Validate that the bounds are reasonable and that each of the elements
1823 have the same size. */
1824
1825 nelem = highbound - lowbound + 1;
1826 if (nelem <= 0)
1827 {
1828 error ("bad array bounds (%d, %d)", lowbound, highbound);
1829 }
1830 typelength = TYPE_LENGTH (VALUE_ENCLOSING_TYPE (elemvec[0]));
1831 for (idx = 1; idx < nelem; idx++)
1832 {
1833 if (TYPE_LENGTH (VALUE_ENCLOSING_TYPE (elemvec[idx])) != typelength)
1834 {
1835 error ("array elements must all be the same size");
1836 }
1837 }
1838
1839 rangetype = create_range_type ((struct type *) NULL, builtin_type_int,
1840 lowbound, highbound);
1841 arraytype = create_array_type ((struct type *) NULL,
1842 VALUE_ENCLOSING_TYPE (elemvec[0]), rangetype);
1843
1844 if (!current_language->c_style_arrays)
1845 {
1846 val = allocate_value (arraytype);
1847 for (idx = 0; idx < nelem; idx++)
1848 {
1849 memcpy (VALUE_CONTENTS_ALL_RAW (val) + (idx * typelength),
1850 VALUE_CONTENTS_ALL (elemvec[idx]),
1851 typelength);
1852 }
1853 VALUE_BFD_SECTION (val) = VALUE_BFD_SECTION (elemvec[0]);
1854 return val;
1855 }
1856
1857 /* Allocate space to store the array in the inferior, and then initialize
1858 it by copying in each element. FIXME: Is it worth it to create a
1859 local buffer in which to collect each value and then write all the
1860 bytes in one operation? */
1861
1862 addr = allocate_space_in_inferior (nelem * typelength);
1863 for (idx = 0; idx < nelem; idx++)
1864 {
1865 write_memory (addr + (idx * typelength), VALUE_CONTENTS_ALL (elemvec[idx]),
1866 typelength);
1867 }
1868
1869 /* Create the array type and set up an array value to be evaluated lazily. */
1870
1871 val = value_at_lazy (arraytype, addr, VALUE_BFD_SECTION (elemvec[0]));
1872 return (val);
1873 }
1874
1875 /* Create a value for a string constant by allocating space in the inferior,
1876 copying the data into that space, and returning the address with type
1877 TYPE_CODE_STRING. PTR points to the string constant data; LEN is number
1878 of characters.
1879 Note that string types are like array of char types with a lower bound of
1880 zero and an upper bound of LEN - 1. Also note that the string may contain
1881 embedded null bytes. */
1882
1883 struct value *
1884 value_string (char *ptr, int len)
1885 {
1886 struct value *val;
1887 int lowbound = current_language->string_lower_bound;
1888 struct type *rangetype = create_range_type ((struct type *) NULL,
1889 builtin_type_int,
1890 lowbound, len + lowbound - 1);
1891 struct type *stringtype
1892 = create_string_type ((struct type *) NULL, rangetype);
1893 CORE_ADDR addr;
1894
1895 if (current_language->c_style_arrays == 0)
1896 {
1897 val = allocate_value (stringtype);
1898 memcpy (VALUE_CONTENTS_RAW (val), ptr, len);
1899 return val;
1900 }
1901
1902
1903 /* Allocate space to store the string in the inferior, and then
1904 copy LEN bytes from PTR in gdb to that address in the inferior. */
1905
1906 addr = allocate_space_in_inferior (len);
1907 write_memory (addr, ptr, len);
1908
1909 val = value_at_lazy (stringtype, addr, NULL);
1910 return (val);
1911 }
1912
1913 struct value *
1914 value_bitstring (char *ptr, int len)
1915 {
1916 struct value *val;
1917 struct type *domain_type = create_range_type (NULL, builtin_type_int,
1918 0, len - 1);
1919 struct type *type = create_set_type ((struct type *) NULL, domain_type);
1920 TYPE_CODE (type) = TYPE_CODE_BITSTRING;
1921 val = allocate_value (type);
1922 memcpy (VALUE_CONTENTS_RAW (val), ptr, TYPE_LENGTH (type));
1923 return val;
1924 }
1925 \f
1926 /* See if we can pass arguments in T2 to a function which takes arguments
1927 of types T1. Both t1 and t2 are NULL-terminated vectors. If some
1928 arguments need coercion of some sort, then the coerced values are written
1929 into T2. Return value is 0 if the arguments could be matched, or the
1930 position at which they differ if not.
1931
1932 STATICP is nonzero if the T1 argument list came from a
1933 static member function.
1934
1935 For non-static member functions, we ignore the first argument,
1936 which is the type of the instance variable. This is because we want
1937 to handle calls with objects from derived classes. This is not
1938 entirely correct: we should actually check to make sure that a
1939 requested operation is type secure, shouldn't we? FIXME. */
1940
1941 static int
1942 typecmp (int staticp, struct type *t1[], struct value *t2[])
1943 {
1944 int i;
1945
1946 if (t2 == 0)
1947 return 1;
1948 if (staticp && t1 == 0)
1949 return t2[1] != 0;
1950 if (t1 == 0)
1951 return 1;
1952 if (TYPE_CODE (t1[0]) == TYPE_CODE_VOID)
1953 return 0;
1954 if (t1[!staticp] == 0)
1955 return 0;
1956 for (i = !staticp; t1[i] && TYPE_CODE (t1[i]) != TYPE_CODE_VOID; i++)
1957 {
1958 struct type *tt1, *tt2;
1959 if (!t2[i])
1960 return i + 1;
1961 tt1 = check_typedef (t1[i]);
1962 tt2 = check_typedef (VALUE_TYPE (t2[i]));
1963 if (TYPE_CODE (tt1) == TYPE_CODE_REF
1964 /* We should be doing hairy argument matching, as below. */
1965 && (TYPE_CODE (check_typedef (TYPE_TARGET_TYPE (tt1))) == TYPE_CODE (tt2)))
1966 {
1967 if (TYPE_CODE (tt2) == TYPE_CODE_ARRAY)
1968 t2[i] = value_coerce_array (t2[i]);
1969 else
1970 t2[i] = value_addr (t2[i]);
1971 continue;
1972 }
1973
1974 /* djb - 20000715 - Until the new type structure is in the
1975 place, and we can attempt things like implicit conversions,
1976 we need to do this so you can take something like a map<const
1977 char *>, and properly access map["hello"], because the
1978 argument to [] will be a reference to a pointer to a char,
1979 and the argument will be a pointer to a char. */
1980 while ( TYPE_CODE(tt1) == TYPE_CODE_REF ||
1981 TYPE_CODE (tt1) == TYPE_CODE_PTR)
1982 {
1983 tt1 = check_typedef( TYPE_TARGET_TYPE(tt1) );
1984 }
1985 while ( TYPE_CODE(tt2) == TYPE_CODE_ARRAY ||
1986 TYPE_CODE(tt2) == TYPE_CODE_PTR ||
1987 TYPE_CODE(tt2) == TYPE_CODE_REF)
1988 {
1989 tt2 = check_typedef( TYPE_TARGET_TYPE(tt2) );
1990 }
1991 if (TYPE_CODE (tt1) == TYPE_CODE (tt2))
1992 continue;
1993 /* Array to pointer is a `trivial conversion' according to the ARM. */
1994
1995 /* We should be doing much hairier argument matching (see section 13.2
1996 of the ARM), but as a quick kludge, just check for the same type
1997 code. */
1998 if (TYPE_CODE (t1[i]) != TYPE_CODE (VALUE_TYPE (t2[i])))
1999 return i + 1;
2000 }
2001 if (!t1[i])
2002 return 0;
2003 return t2[i] ? i + 1 : 0;
2004 }
2005
2006 /* Helper function used by value_struct_elt to recurse through baseclasses.
2007 Look for a field NAME in ARG1. Adjust the address of ARG1 by OFFSET bytes,
2008 and search in it assuming it has (class) type TYPE.
2009 If found, return value, else return NULL.
2010
2011 If LOOKING_FOR_BASECLASS, then instead of looking for struct fields,
2012 look for a baseclass named NAME. */
2013
2014 static struct value *
2015 search_struct_field (char *name, struct value *arg1, int offset,
2016 register struct type *type, int looking_for_baseclass)
2017 {
2018 int i;
2019 int nbases = TYPE_N_BASECLASSES (type);
2020
2021 CHECK_TYPEDEF (type);
2022
2023 if (!looking_for_baseclass)
2024 for (i = TYPE_NFIELDS (type) - 1; i >= nbases; i--)
2025 {
2026 char *t_field_name = TYPE_FIELD_NAME (type, i);
2027
2028 if (t_field_name && (strcmp_iw (t_field_name, name) == 0))
2029 {
2030 struct value *v;
2031 if (TYPE_FIELD_STATIC (type, i))
2032 v = value_static_field (type, i);
2033 else
2034 v = value_primitive_field (arg1, offset, i, type);
2035 if (v == 0)
2036 error ("there is no field named %s", name);
2037 return v;
2038 }
2039
2040 if (t_field_name
2041 && (t_field_name[0] == '\0'
2042 || (TYPE_CODE (type) == TYPE_CODE_UNION
2043 && (strcmp_iw (t_field_name, "else") == 0))))
2044 {
2045 struct type *field_type = TYPE_FIELD_TYPE (type, i);
2046 if (TYPE_CODE (field_type) == TYPE_CODE_UNION
2047 || TYPE_CODE (field_type) == TYPE_CODE_STRUCT)
2048 {
2049 /* Look for a match through the fields of an anonymous union,
2050 or anonymous struct. C++ provides anonymous unions.
2051
2052 In the GNU Chill implementation of variant record types,
2053 each <alternative field> has an (anonymous) union type,
2054 each member of the union represents a <variant alternative>.
2055 Each <variant alternative> is represented as a struct,
2056 with a member for each <variant field>. */
2057
2058 struct value *v;
2059 int new_offset = offset;
2060
2061 /* This is pretty gross. In G++, the offset in an anonymous
2062 union is relative to the beginning of the enclosing struct.
2063 In the GNU Chill implementation of variant records,
2064 the bitpos is zero in an anonymous union field, so we
2065 have to add the offset of the union here. */
2066 if (TYPE_CODE (field_type) == TYPE_CODE_STRUCT
2067 || (TYPE_NFIELDS (field_type) > 0
2068 && TYPE_FIELD_BITPOS (field_type, 0) == 0))
2069 new_offset += TYPE_FIELD_BITPOS (type, i) / 8;
2070
2071 v = search_struct_field (name, arg1, new_offset, field_type,
2072 looking_for_baseclass);
2073 if (v)
2074 return v;
2075 }
2076 }
2077 }
2078
2079 for (i = 0; i < nbases; i++)
2080 {
2081 struct value *v;
2082 struct type *basetype = check_typedef (TYPE_BASECLASS (type, i));
2083 /* If we are looking for baseclasses, this is what we get when we
2084 hit them. But it could happen that the base part's member name
2085 is not yet filled in. */
2086 int found_baseclass = (looking_for_baseclass
2087 && TYPE_BASECLASS_NAME (type, i) != NULL
2088 && (strcmp_iw (name, TYPE_BASECLASS_NAME (type, i)) == 0));
2089
2090 if (BASETYPE_VIA_VIRTUAL (type, i))
2091 {
2092 int boffset;
2093 struct value *v2 = allocate_value (basetype);
2094
2095 boffset = baseclass_offset (type, i,
2096 VALUE_CONTENTS (arg1) + offset,
2097 VALUE_ADDRESS (arg1)
2098 + VALUE_OFFSET (arg1) + offset);
2099 if (boffset == -1)
2100 error ("virtual baseclass botch");
2101
2102 /* The virtual base class pointer might have been clobbered by the
2103 user program. Make sure that it still points to a valid memory
2104 location. */
2105
2106 boffset += offset;
2107 if (boffset < 0 || boffset >= TYPE_LENGTH (type))
2108 {
2109 CORE_ADDR base_addr;
2110
2111 base_addr = VALUE_ADDRESS (arg1) + VALUE_OFFSET (arg1) + boffset;
2112 if (target_read_memory (base_addr, VALUE_CONTENTS_RAW (v2),
2113 TYPE_LENGTH (basetype)) != 0)
2114 error ("virtual baseclass botch");
2115 VALUE_LVAL (v2) = lval_memory;
2116 VALUE_ADDRESS (v2) = base_addr;
2117 }
2118 else
2119 {
2120 VALUE_LVAL (v2) = VALUE_LVAL (arg1);
2121 VALUE_ADDRESS (v2) = VALUE_ADDRESS (arg1);
2122 VALUE_OFFSET (v2) = VALUE_OFFSET (arg1) + boffset;
2123 if (VALUE_LAZY (arg1))
2124 VALUE_LAZY (v2) = 1;
2125 else
2126 memcpy (VALUE_CONTENTS_RAW (v2),
2127 VALUE_CONTENTS_RAW (arg1) + boffset,
2128 TYPE_LENGTH (basetype));
2129 }
2130
2131 if (found_baseclass)
2132 return v2;
2133 v = search_struct_field (name, v2, 0, TYPE_BASECLASS (type, i),
2134 looking_for_baseclass);
2135 }
2136 else if (found_baseclass)
2137 v = value_primitive_field (arg1, offset, i, type);
2138 else
2139 v = search_struct_field (name, arg1,
2140 offset + TYPE_BASECLASS_BITPOS (type, i) / 8,
2141 basetype, looking_for_baseclass);
2142 if (v)
2143 return v;
2144 }
2145 return NULL;
2146 }
2147
2148
2149 /* Return the offset (in bytes) of the virtual base of type BASETYPE
2150 * in an object pointed to by VALADDR (on the host), assumed to be of
2151 * type TYPE. OFFSET is number of bytes beyond start of ARG to start
2152 * looking (in case VALADDR is the contents of an enclosing object).
2153 *
2154 * This routine recurses on the primary base of the derived class because
2155 * the virtual base entries of the primary base appear before the other
2156 * virtual base entries.
2157 *
2158 * If the virtual base is not found, a negative integer is returned.
2159 * The magnitude of the negative integer is the number of entries in
2160 * the virtual table to skip over (entries corresponding to various
2161 * ancestral classes in the chain of primary bases).
2162 *
2163 * Important: This assumes the HP / Taligent C++ runtime
2164 * conventions. Use baseclass_offset() instead to deal with g++
2165 * conventions. */
2166
2167 void
2168 find_rt_vbase_offset (struct type *type, struct type *basetype, char *valaddr,
2169 int offset, int *boffset_p, int *skip_p)
2170 {
2171 int boffset; /* offset of virtual base */
2172 int index; /* displacement to use in virtual table */
2173 int skip;
2174
2175 struct value *vp;
2176 CORE_ADDR vtbl; /* the virtual table pointer */
2177 struct type *pbc; /* the primary base class */
2178
2179 /* Look for the virtual base recursively in the primary base, first.
2180 * This is because the derived class object and its primary base
2181 * subobject share the primary virtual table. */
2182
2183 boffset = 0;
2184 pbc = TYPE_PRIMARY_BASE (type);
2185 if (pbc)
2186 {
2187 find_rt_vbase_offset (pbc, basetype, valaddr, offset, &boffset, &skip);
2188 if (skip < 0)
2189 {
2190 *boffset_p = boffset;
2191 *skip_p = -1;
2192 return;
2193 }
2194 }
2195 else
2196 skip = 0;
2197
2198
2199 /* Find the index of the virtual base according to HP/Taligent
2200 runtime spec. (Depth-first, left-to-right.) */
2201 index = virtual_base_index_skip_primaries (basetype, type);
2202
2203 if (index < 0)
2204 {
2205 *skip_p = skip + virtual_base_list_length_skip_primaries (type);
2206 *boffset_p = 0;
2207 return;
2208 }
2209
2210 /* pai: FIXME -- 32x64 possible problem */
2211 /* First word (4 bytes) in object layout is the vtable pointer */
2212 vtbl = *(CORE_ADDR *) (valaddr + offset);
2213
2214 /* Before the constructor is invoked, things are usually zero'd out. */
2215 if (vtbl == 0)
2216 error ("Couldn't find virtual table -- object may not be constructed yet.");
2217
2218
2219 /* Find virtual base's offset -- jump over entries for primary base
2220 * ancestors, then use the index computed above. But also adjust by
2221 * HP_ACC_VBASE_START for the vtable slots before the start of the
2222 * virtual base entries. Offset is negative -- virtual base entries
2223 * appear _before_ the address point of the virtual table. */
2224
2225 /* pai: FIXME -- 32x64 problem, if word = 8 bytes, change multiplier
2226 & use long type */
2227
2228 /* epstein : FIXME -- added param for overlay section. May not be correct */
2229 vp = value_at (builtin_type_int, vtbl + 4 * (-skip - index - HP_ACC_VBASE_START), NULL);
2230 boffset = value_as_long (vp);
2231 *skip_p = -1;
2232 *boffset_p = boffset;
2233 return;
2234 }
2235
2236
2237 /* Helper function used by value_struct_elt to recurse through baseclasses.
2238 Look for a field NAME in ARG1. Adjust the address of ARG1 by OFFSET bytes,
2239 and search in it assuming it has (class) type TYPE.
2240 If found, return value, else if name matched and args not return (value)-1,
2241 else return NULL. */
2242
2243 static struct value *
2244 search_struct_method (char *name, struct value **arg1p,
2245 struct value **args, int offset,
2246 int *static_memfuncp, register struct type *type)
2247 {
2248 int i;
2249 struct value *v;
2250 int name_matched = 0;
2251 char dem_opname[64];
2252
2253 CHECK_TYPEDEF (type);
2254 for (i = TYPE_NFN_FIELDS (type) - 1; i >= 0; i--)
2255 {
2256 char *t_field_name = TYPE_FN_FIELDLIST_NAME (type, i);
2257 /* FIXME! May need to check for ARM demangling here */
2258 if (strncmp (t_field_name, "__", 2) == 0 ||
2259 strncmp (t_field_name, "op", 2) == 0 ||
2260 strncmp (t_field_name, "type", 4) == 0)
2261 {
2262 if (cplus_demangle_opname (t_field_name, dem_opname, DMGL_ANSI))
2263 t_field_name = dem_opname;
2264 else if (cplus_demangle_opname (t_field_name, dem_opname, 0))
2265 t_field_name = dem_opname;
2266 }
2267 if (t_field_name && (strcmp_iw (t_field_name, name) == 0))
2268 {
2269 int j = TYPE_FN_FIELDLIST_LENGTH (type, i) - 1;
2270 struct fn_field *f = TYPE_FN_FIELDLIST1 (type, i);
2271 name_matched = 1;
2272
2273 if (j > 0 && args == 0)
2274 error ("cannot resolve overloaded method `%s': no arguments supplied", name);
2275 while (j >= 0)
2276 {
2277 if (TYPE_FN_FIELD_STUB (f, j))
2278 check_stub_method (type, i, j);
2279 if (!typecmp (TYPE_FN_FIELD_STATIC_P (f, j),
2280 TYPE_FN_FIELD_ARGS (f, j), args))
2281 {
2282 if (TYPE_FN_FIELD_VIRTUAL_P (f, j))
2283 return value_virtual_fn_field (arg1p, f, j, type, offset);
2284 if (TYPE_FN_FIELD_STATIC_P (f, j) && static_memfuncp)
2285 *static_memfuncp = 1;
2286 v = value_fn_field (arg1p, f, j, type, offset);
2287 if (v != NULL)
2288 return v;
2289 }
2290 j--;
2291 }
2292 }
2293 }
2294
2295 for (i = TYPE_N_BASECLASSES (type) - 1; i >= 0; i--)
2296 {
2297 int base_offset;
2298
2299 if (BASETYPE_VIA_VIRTUAL (type, i))
2300 {
2301 if (TYPE_HAS_VTABLE (type))
2302 {
2303 /* HP aCC compiled type, search for virtual base offset
2304 according to HP/Taligent runtime spec. */
2305 int skip;
2306 find_rt_vbase_offset (type, TYPE_BASECLASS (type, i),
2307 VALUE_CONTENTS_ALL (*arg1p),
2308 offset + VALUE_EMBEDDED_OFFSET (*arg1p),
2309 &base_offset, &skip);
2310 if (skip >= 0)
2311 error ("Virtual base class offset not found in vtable");
2312 }
2313 else
2314 {
2315 struct type *baseclass = check_typedef (TYPE_BASECLASS (type, i));
2316 char *base_valaddr;
2317
2318 /* The virtual base class pointer might have been clobbered by the
2319 user program. Make sure that it still points to a valid memory
2320 location. */
2321
2322 if (offset < 0 || offset >= TYPE_LENGTH (type))
2323 {
2324 base_valaddr = (char *) alloca (TYPE_LENGTH (baseclass));
2325 if (target_read_memory (VALUE_ADDRESS (*arg1p)
2326 + VALUE_OFFSET (*arg1p) + offset,
2327 base_valaddr,
2328 TYPE_LENGTH (baseclass)) != 0)
2329 error ("virtual baseclass botch");
2330 }
2331 else
2332 base_valaddr = VALUE_CONTENTS (*arg1p) + offset;
2333
2334 base_offset =
2335 baseclass_offset (type, i, base_valaddr,
2336 VALUE_ADDRESS (*arg1p)
2337 + VALUE_OFFSET (*arg1p) + offset);
2338 if (base_offset == -1)
2339 error ("virtual baseclass botch");
2340 }
2341 }
2342 else
2343 {
2344 base_offset = TYPE_BASECLASS_BITPOS (type, i) / 8;
2345 }
2346 v = search_struct_method (name, arg1p, args, base_offset + offset,
2347 static_memfuncp, TYPE_BASECLASS (type, i));
2348 if (v == (struct value *) - 1)
2349 {
2350 name_matched = 1;
2351 }
2352 else if (v)
2353 {
2354 /* FIXME-bothner: Why is this commented out? Why is it here? */
2355 /* *arg1p = arg1_tmp; */
2356 return v;
2357 }
2358 }
2359 if (name_matched)
2360 return (struct value *) - 1;
2361 else
2362 return NULL;
2363 }
2364
2365 /* Given *ARGP, a value of type (pointer to a)* structure/union,
2366 extract the component named NAME from the ultimate target structure/union
2367 and return it as a value with its appropriate type.
2368 ERR is used in the error message if *ARGP's type is wrong.
2369
2370 C++: ARGS is a list of argument types to aid in the selection of
2371 an appropriate method. Also, handle derived types.
2372
2373 STATIC_MEMFUNCP, if non-NULL, points to a caller-supplied location
2374 where the truthvalue of whether the function that was resolved was
2375 a static member function or not is stored.
2376
2377 ERR is an error message to be printed in case the field is not found. */
2378
2379 struct value *
2380 value_struct_elt (struct value **argp, struct value **args,
2381 char *name, int *static_memfuncp, char *err)
2382 {
2383 register struct type *t;
2384 struct value *v;
2385
2386 COERCE_ARRAY (*argp);
2387
2388 t = check_typedef (VALUE_TYPE (*argp));
2389
2390 /* Follow pointers until we get to a non-pointer. */
2391
2392 while (TYPE_CODE (t) == TYPE_CODE_PTR || TYPE_CODE (t) == TYPE_CODE_REF)
2393 {
2394 *argp = value_ind (*argp);
2395 /* Don't coerce fn pointer to fn and then back again! */
2396 if (TYPE_CODE (VALUE_TYPE (*argp)) != TYPE_CODE_FUNC)
2397 COERCE_ARRAY (*argp);
2398 t = check_typedef (VALUE_TYPE (*argp));
2399 }
2400
2401 if (TYPE_CODE (t) == TYPE_CODE_MEMBER)
2402 error ("not implemented: member type in value_struct_elt");
2403
2404 if (TYPE_CODE (t) != TYPE_CODE_STRUCT
2405 && TYPE_CODE (t) != TYPE_CODE_UNION)
2406 error ("Attempt to extract a component of a value that is not a %s.", err);
2407
2408 /* Assume it's not, unless we see that it is. */
2409 if (static_memfuncp)
2410 *static_memfuncp = 0;
2411
2412 if (!args)
2413 {
2414 /* if there are no arguments ...do this... */
2415
2416 /* Try as a field first, because if we succeed, there
2417 is less work to be done. */
2418 v = search_struct_field (name, *argp, 0, t, 0);
2419 if (v)
2420 return v;
2421
2422 /* C++: If it was not found as a data field, then try to
2423 return it as a pointer to a method. */
2424
2425 if (destructor_name_p (name, t))
2426 error ("Cannot get value of destructor");
2427
2428 v = search_struct_method (name, argp, args, 0, static_memfuncp, t);
2429
2430 if (v == (struct value *) - 1)
2431 error ("Cannot take address of a method");
2432 else if (v == 0)
2433 {
2434 if (TYPE_NFN_FIELDS (t))
2435 error ("There is no member or method named %s.", name);
2436 else
2437 error ("There is no member named %s.", name);
2438 }
2439 return v;
2440 }
2441
2442 if (destructor_name_p (name, t))
2443 {
2444 if (!args[1])
2445 {
2446 /* Destructors are a special case. */
2447 int m_index, f_index;
2448
2449 v = NULL;
2450 if (get_destructor_fn_field (t, &m_index, &f_index))
2451 {
2452 v = value_fn_field (NULL, TYPE_FN_FIELDLIST1 (t, m_index),
2453 f_index, NULL, 0);
2454 }
2455 if (v == NULL)
2456 error ("could not find destructor function named %s.", name);
2457 else
2458 return v;
2459 }
2460 else
2461 {
2462 error ("destructor should not have any argument");
2463 }
2464 }
2465 else
2466 v = search_struct_method (name, argp, args, 0, static_memfuncp, t);
2467
2468 if (v == (struct value *) - 1)
2469 {
2470 error ("One of the arguments you tried to pass to %s could not be converted to what the function wants.", name);
2471 }
2472 else if (v == 0)
2473 {
2474 /* See if user tried to invoke data as function. If so,
2475 hand it back. If it's not callable (i.e., a pointer to function),
2476 gdb should give an error. */
2477 v = search_struct_field (name, *argp, 0, t, 0);
2478 }
2479
2480 if (!v)
2481 error ("Structure has no component named %s.", name);
2482 return v;
2483 }
2484
2485 /* Search through the methods of an object (and its bases)
2486 * to find a specified method. Return the pointer to the
2487 * fn_field list of overloaded instances.
2488 * Helper function for value_find_oload_list.
2489 * ARGP is a pointer to a pointer to a value (the object)
2490 * METHOD is a string containing the method name
2491 * OFFSET is the offset within the value
2492 * STATIC_MEMFUNCP is set if the method is static
2493 * TYPE is the assumed type of the object
2494 * NUM_FNS is the number of overloaded instances
2495 * BASETYPE is set to the actual type of the subobject where the method is found
2496 * BOFFSET is the offset of the base subobject where the method is found */
2497
2498 static struct fn_field *
2499 find_method_list (struct value **argp, char *method, int offset,
2500 int *static_memfuncp, struct type *type, int *num_fns,
2501 struct type **basetype, int *boffset)
2502 {
2503 int i;
2504 struct fn_field *f;
2505 CHECK_TYPEDEF (type);
2506
2507 *num_fns = 0;
2508
2509 /* First check in object itself */
2510 for (i = TYPE_NFN_FIELDS (type) - 1; i >= 0; i--)
2511 {
2512 /* pai: FIXME What about operators and type conversions? */
2513 char *fn_field_name = TYPE_FN_FIELDLIST_NAME (type, i);
2514 if (fn_field_name && (strcmp_iw (fn_field_name, method) == 0))
2515 {
2516 *num_fns = TYPE_FN_FIELDLIST_LENGTH (type, i);
2517 *basetype = type;
2518 *boffset = offset;
2519 return TYPE_FN_FIELDLIST1 (type, i);
2520 }
2521 }
2522
2523 /* Not found in object, check in base subobjects */
2524 for (i = TYPE_N_BASECLASSES (type) - 1; i >= 0; i--)
2525 {
2526 int base_offset;
2527 if (BASETYPE_VIA_VIRTUAL (type, i))
2528 {
2529 if (TYPE_HAS_VTABLE (type))
2530 {
2531 /* HP aCC compiled type, search for virtual base offset
2532 * according to HP/Taligent runtime spec. */
2533 int skip;
2534 find_rt_vbase_offset (type, TYPE_BASECLASS (type, i),
2535 VALUE_CONTENTS_ALL (*argp),
2536 offset + VALUE_EMBEDDED_OFFSET (*argp),
2537 &base_offset, &skip);
2538 if (skip >= 0)
2539 error ("Virtual base class offset not found in vtable");
2540 }
2541 else
2542 {
2543 /* probably g++ runtime model */
2544 base_offset = VALUE_OFFSET (*argp) + offset;
2545 base_offset =
2546 baseclass_offset (type, i,
2547 VALUE_CONTENTS (*argp) + base_offset,
2548 VALUE_ADDRESS (*argp) + base_offset);
2549 if (base_offset == -1)
2550 error ("virtual baseclass botch");
2551 }
2552 }
2553 else
2554 /* non-virtual base, simply use bit position from debug info */
2555 {
2556 base_offset = TYPE_BASECLASS_BITPOS (type, i) / 8;
2557 }
2558 f = find_method_list (argp, method, base_offset + offset,
2559 static_memfuncp, TYPE_BASECLASS (type, i), num_fns, basetype, boffset);
2560 if (f)
2561 return f;
2562 }
2563 return NULL;
2564 }
2565
2566 /* Return the list of overloaded methods of a specified name.
2567 * ARGP is a pointer to a pointer to a value (the object)
2568 * METHOD is the method name
2569 * OFFSET is the offset within the value contents
2570 * STATIC_MEMFUNCP is set if the method is static
2571 * NUM_FNS is the number of overloaded instances
2572 * BASETYPE is set to the type of the base subobject that defines the method
2573 * BOFFSET is the offset of the base subobject which defines the method */
2574
2575 struct fn_field *
2576 value_find_oload_method_list (struct value **argp, char *method, int offset,
2577 int *static_memfuncp, int *num_fns,
2578 struct type **basetype, int *boffset)
2579 {
2580 struct type *t;
2581
2582 t = check_typedef (VALUE_TYPE (*argp));
2583
2584 /* code snarfed from value_struct_elt */
2585 while (TYPE_CODE (t) == TYPE_CODE_PTR || TYPE_CODE (t) == TYPE_CODE_REF)
2586 {
2587 *argp = value_ind (*argp);
2588 /* Don't coerce fn pointer to fn and then back again! */
2589 if (TYPE_CODE (VALUE_TYPE (*argp)) != TYPE_CODE_FUNC)
2590 COERCE_ARRAY (*argp);
2591 t = check_typedef (VALUE_TYPE (*argp));
2592 }
2593
2594 if (TYPE_CODE (t) == TYPE_CODE_MEMBER)
2595 error ("Not implemented: member type in value_find_oload_lis");
2596
2597 if (TYPE_CODE (t) != TYPE_CODE_STRUCT
2598 && TYPE_CODE (t) != TYPE_CODE_UNION)
2599 error ("Attempt to extract a component of a value that is not a struct or union");
2600
2601 /* Assume it's not static, unless we see that it is. */
2602 if (static_memfuncp)
2603 *static_memfuncp = 0;
2604
2605 return find_method_list (argp, method, 0, static_memfuncp, t, num_fns, basetype, boffset);
2606
2607 }
2608
2609 /* Given an array of argument types (ARGTYPES) (which includes an
2610 entry for "this" in the case of C++ methods), the number of
2611 arguments NARGS, the NAME of a function whether it's a method or
2612 not (METHOD), and the degree of laxness (LAX) in conforming to
2613 overload resolution rules in ANSI C++, find the best function that
2614 matches on the argument types according to the overload resolution
2615 rules.
2616
2617 In the case of class methods, the parameter OBJ is an object value
2618 in which to search for overloaded methods.
2619
2620 In the case of non-method functions, the parameter FSYM is a symbol
2621 corresponding to one of the overloaded functions.
2622
2623 Return value is an integer: 0 -> good match, 10 -> debugger applied
2624 non-standard coercions, 100 -> incompatible.
2625
2626 If a method is being searched for, VALP will hold the value.
2627 If a non-method is being searched for, SYMP will hold the symbol for it.
2628
2629 If a method is being searched for, and it is a static method,
2630 then STATICP will point to a non-zero value.
2631
2632 Note: This function does *not* check the value of
2633 overload_resolution. Caller must check it to see whether overload
2634 resolution is permitted.
2635 */
2636
2637 int
2638 find_overload_match (struct type **arg_types, int nargs, char *name, int method,
2639 int lax, struct value **objp, struct symbol *fsym,
2640 struct value **valp, struct symbol **symp, int *staticp)
2641 {
2642 int nparms;
2643 struct type **parm_types;
2644 int champ_nparms = 0;
2645 struct value *obj = (objp ? *objp : NULL);
2646
2647 short oload_champ = -1; /* Index of best overloaded function */
2648 short oload_ambiguous = 0; /* Current ambiguity state for overload resolution */
2649 /* 0 => no ambiguity, 1 => two good funcs, 2 => incomparable funcs */
2650 short oload_ambig_champ = -1; /* 2nd contender for best match */
2651 short oload_non_standard = 0; /* did we have to use non-standard conversions? */
2652 short oload_incompatible = 0; /* are args supplied incompatible with any function? */
2653
2654 struct badness_vector *bv; /* A measure of how good an overloaded instance is */
2655 struct badness_vector *oload_champ_bv = NULL; /* The measure for the current best match */
2656
2657 struct value *temp = obj;
2658 struct fn_field *fns_ptr = NULL; /* For methods, the list of overloaded methods */
2659 struct symbol **oload_syms = NULL; /* For non-methods, the list of overloaded function symbols */
2660 int num_fns = 0; /* Number of overloaded instances being considered */
2661 struct type *basetype = NULL;
2662 int boffset;
2663 register int jj;
2664 register int ix;
2665
2666 char *obj_type_name = NULL;
2667 char *func_name = NULL;
2668
2669 /* Get the list of overloaded methods or functions */
2670 if (method)
2671 {
2672 int i;
2673 int len;
2674 struct type *domain;
2675 obj_type_name = TYPE_NAME (VALUE_TYPE (obj));
2676 /* Hack: evaluate_subexp_standard often passes in a pointer
2677 value rather than the object itself, so try again */
2678 if ((!obj_type_name || !*obj_type_name) &&
2679 (TYPE_CODE (VALUE_TYPE (obj)) == TYPE_CODE_PTR))
2680 obj_type_name = TYPE_NAME (TYPE_TARGET_TYPE (VALUE_TYPE (obj)));
2681
2682 fns_ptr = value_find_oload_method_list (&temp, name, 0,
2683 staticp,
2684 &num_fns,
2685 &basetype, &boffset);
2686 if (!fns_ptr || !num_fns)
2687 error ("Couldn't find method %s%s%s",
2688 obj_type_name,
2689 (obj_type_name && *obj_type_name) ? "::" : "",
2690 name);
2691 domain = TYPE_DOMAIN_TYPE (fns_ptr[0].type);
2692 len = TYPE_NFN_FIELDS (domain);
2693 /* NOTE: dan/2000-03-10: This stuff is for STABS, which won't
2694 give us the info we need directly in the types. We have to
2695 use the method stub conversion to get it. Be aware that this
2696 is by no means perfect, and if you use STABS, please move to
2697 DWARF-2, or something like it, because trying to improve
2698 overloading using STABS is really a waste of time. */
2699 for (i = 0; i < len; i++)
2700 {
2701 int j;
2702 struct fn_field *f = TYPE_FN_FIELDLIST1 (domain, i);
2703 int len2 = TYPE_FN_FIELDLIST_LENGTH (domain, i);
2704
2705 for (j = 0; j < len2; j++)
2706 {
2707 if (TYPE_FN_FIELD_STUB (f, j) && (!strcmp_iw (TYPE_FN_FIELDLIST_NAME (domain,i),name)))
2708 check_stub_method (domain, i, j);
2709 }
2710 }
2711 }
2712 else
2713 {
2714 int i = -1;
2715 func_name = cplus_demangle (SYMBOL_NAME (fsym), DMGL_NO_OPTS);
2716
2717 /* If the name is NULL this must be a C-style function.
2718 Just return the same symbol. */
2719 if (!func_name)
2720 {
2721 *symp = fsym;
2722 return 0;
2723 }
2724
2725 oload_syms = make_symbol_overload_list (fsym);
2726 while (oload_syms[++i])
2727 num_fns++;
2728 if (!num_fns)
2729 error ("Couldn't find function %s", func_name);
2730 }
2731
2732 oload_champ_bv = NULL;
2733
2734 /* Consider each candidate in turn */
2735 for (ix = 0; ix < num_fns; ix++)
2736 {
2737 if (method)
2738 {
2739 /* For static member functions, we won't have a this pointer, but nothing
2740 else seems to handle them right now, so we just pretend ourselves */
2741 nparms=0;
2742
2743 if (TYPE_FN_FIELD_ARGS(fns_ptr,ix))
2744 {
2745 while (TYPE_CODE(TYPE_FN_FIELD_ARGS(fns_ptr,ix)[nparms]) != TYPE_CODE_VOID)
2746 nparms++;
2747 }
2748 }
2749 else
2750 {
2751 /* If it's not a method, this is the proper place */
2752 nparms=TYPE_NFIELDS(SYMBOL_TYPE(oload_syms[ix]));
2753 }
2754
2755 /* Prepare array of parameter types */
2756 parm_types = (struct type **) xmalloc (nparms * (sizeof (struct type *)));
2757 for (jj = 0; jj < nparms; jj++)
2758 parm_types[jj] = (method
2759 ? (TYPE_FN_FIELD_ARGS (fns_ptr, ix)[jj])
2760 : TYPE_FIELD_TYPE (SYMBOL_TYPE (oload_syms[ix]), jj));
2761
2762 /* Compare parameter types to supplied argument types */
2763 bv = rank_function (parm_types, nparms, arg_types, nargs);
2764
2765 if (!oload_champ_bv)
2766 {
2767 oload_champ_bv = bv;
2768 oload_champ = 0;
2769 champ_nparms = nparms;
2770 }
2771 else
2772 /* See whether current candidate is better or worse than previous best */
2773 switch (compare_badness (bv, oload_champ_bv))
2774 {
2775 case 0:
2776 oload_ambiguous = 1; /* top two contenders are equally good */
2777 oload_ambig_champ = ix;
2778 break;
2779 case 1:
2780 oload_ambiguous = 2; /* incomparable top contenders */
2781 oload_ambig_champ = ix;
2782 break;
2783 case 2:
2784 oload_champ_bv = bv; /* new champion, record details */
2785 oload_ambiguous = 0;
2786 oload_champ = ix;
2787 oload_ambig_champ = -1;
2788 champ_nparms = nparms;
2789 break;
2790 case 3:
2791 default:
2792 break;
2793 }
2794 xfree (parm_types);
2795 if (overload_debug)
2796 {
2797 if (method)
2798 fprintf_filtered (gdb_stderr,"Overloaded method instance %s, # of parms %d\n", fns_ptr[ix].physname, nparms);
2799 else
2800 fprintf_filtered (gdb_stderr,"Overloaded function instance %s # of parms %d\n", SYMBOL_DEMANGLED_NAME (oload_syms[ix]), nparms);
2801 for (jj = 0; jj < nargs; jj++)
2802 fprintf_filtered (gdb_stderr,"...Badness @ %d : %d\n", jj, bv->rank[jj]);
2803 fprintf_filtered (gdb_stderr,"Overload resolution champion is %d, ambiguous? %d\n", oload_champ, oload_ambiguous);
2804 }
2805 } /* end loop over all candidates */
2806 /* NOTE: dan/2000-03-10: Seems to be a better idea to just pick one
2807 if they have the exact same goodness. This is because there is no
2808 way to differentiate based on return type, which we need to in
2809 cases like overloads of .begin() <It's both const and non-const> */
2810 #if 0
2811 if (oload_ambiguous)
2812 {
2813 if (method)
2814 error ("Cannot resolve overloaded method %s%s%s to unique instance; disambiguate by specifying function signature",
2815 obj_type_name,
2816 (obj_type_name && *obj_type_name) ? "::" : "",
2817 name);
2818 else
2819 error ("Cannot resolve overloaded function %s to unique instance; disambiguate by specifying function signature",
2820 func_name);
2821 }
2822 #endif
2823
2824 /* Check how bad the best match is */
2825 for (ix = 1; ix <= nargs; ix++)
2826 {
2827 if (oload_champ_bv->rank[ix] >= 100)
2828 oload_incompatible = 1; /* truly mismatched types */
2829
2830 else if (oload_champ_bv->rank[ix] >= 10)
2831 oload_non_standard = 1; /* non-standard type conversions needed */
2832 }
2833 if (oload_incompatible)
2834 {
2835 if (method)
2836 error ("Cannot resolve method %s%s%s to any overloaded instance",
2837 obj_type_name,
2838 (obj_type_name && *obj_type_name) ? "::" : "",
2839 name);
2840 else
2841 error ("Cannot resolve function %s to any overloaded instance",
2842 func_name);
2843 }
2844 else if (oload_non_standard)
2845 {
2846 if (method)
2847 warning ("Using non-standard conversion to match method %s%s%s to supplied arguments",
2848 obj_type_name,
2849 (obj_type_name && *obj_type_name) ? "::" : "",
2850 name);
2851 else
2852 warning ("Using non-standard conversion to match function %s to supplied arguments",
2853 func_name);
2854 }
2855
2856 if (method)
2857 {
2858 if (TYPE_FN_FIELD_VIRTUAL_P (fns_ptr, oload_champ))
2859 *valp = value_virtual_fn_field (&temp, fns_ptr, oload_champ, basetype, boffset);
2860 else
2861 *valp = value_fn_field (&temp, fns_ptr, oload_champ, basetype, boffset);
2862 }
2863 else
2864 {
2865 *symp = oload_syms[oload_champ];
2866 xfree (func_name);
2867 }
2868
2869 if (objp)
2870 {
2871 if (TYPE_CODE (VALUE_TYPE (temp)) != TYPE_CODE_PTR
2872 && TYPE_CODE (VALUE_TYPE (*objp)) == TYPE_CODE_PTR)
2873 {
2874 temp = value_addr (temp);
2875 }
2876 *objp = temp;
2877 }
2878 return oload_incompatible ? 100 : (oload_non_standard ? 10 : 0);
2879 }
2880
2881 /* C++: return 1 is NAME is a legitimate name for the destructor
2882 of type TYPE. If TYPE does not have a destructor, or
2883 if NAME is inappropriate for TYPE, an error is signaled. */
2884 int
2885 destructor_name_p (const char *name, const struct type *type)
2886 {
2887 /* destructors are a special case. */
2888
2889 if (name[0] == '~')
2890 {
2891 char *dname = type_name_no_tag (type);
2892 char *cp = strchr (dname, '<');
2893 unsigned int len;
2894
2895 /* Do not compare the template part for template classes. */
2896 if (cp == NULL)
2897 len = strlen (dname);
2898 else
2899 len = cp - dname;
2900 if (strlen (name + 1) != len || !STREQN (dname, name + 1, len))
2901 error ("name of destructor must equal name of class");
2902 else
2903 return 1;
2904 }
2905 return 0;
2906 }
2907
2908 /* Helper function for check_field: Given TYPE, a structure/union,
2909 return 1 if the component named NAME from the ultimate
2910 target structure/union is defined, otherwise, return 0. */
2911
2912 static int
2913 check_field_in (register struct type *type, const char *name)
2914 {
2915 register int i;
2916
2917 for (i = TYPE_NFIELDS (type) - 1; i >= TYPE_N_BASECLASSES (type); i--)
2918 {
2919 char *t_field_name = TYPE_FIELD_NAME (type, i);
2920 if (t_field_name && (strcmp_iw (t_field_name, name) == 0))
2921 return 1;
2922 }
2923
2924 /* C++: If it was not found as a data field, then try to
2925 return it as a pointer to a method. */
2926
2927 /* Destructors are a special case. */
2928 if (destructor_name_p (name, type))
2929 {
2930 int m_index, f_index;
2931
2932 return get_destructor_fn_field (type, &m_index, &f_index);
2933 }
2934
2935 for (i = TYPE_NFN_FIELDS (type) - 1; i >= 0; --i)
2936 {
2937 if (strcmp_iw (TYPE_FN_FIELDLIST_NAME (type, i), name) == 0)
2938 return 1;
2939 }
2940
2941 for (i = TYPE_N_BASECLASSES (type) - 1; i >= 0; i--)
2942 if (check_field_in (TYPE_BASECLASS (type, i), name))
2943 return 1;
2944
2945 return 0;
2946 }
2947
2948
2949 /* C++: Given ARG1, a value of type (pointer to a)* structure/union,
2950 return 1 if the component named NAME from the ultimate
2951 target structure/union is defined, otherwise, return 0. */
2952
2953 int
2954 check_field (struct value *arg1, const char *name)
2955 {
2956 register struct type *t;
2957
2958 COERCE_ARRAY (arg1);
2959
2960 t = VALUE_TYPE (arg1);
2961
2962 /* Follow pointers until we get to a non-pointer. */
2963
2964 for (;;)
2965 {
2966 CHECK_TYPEDEF (t);
2967 if (TYPE_CODE (t) != TYPE_CODE_PTR && TYPE_CODE (t) != TYPE_CODE_REF)
2968 break;
2969 t = TYPE_TARGET_TYPE (t);
2970 }
2971
2972 if (TYPE_CODE (t) == TYPE_CODE_MEMBER)
2973 error ("not implemented: member type in check_field");
2974
2975 if (TYPE_CODE (t) != TYPE_CODE_STRUCT
2976 && TYPE_CODE (t) != TYPE_CODE_UNION)
2977 error ("Internal error: `this' is not an aggregate");
2978
2979 return check_field_in (t, name);
2980 }
2981
2982 /* C++: Given an aggregate type CURTYPE, and a member name NAME,
2983 return the address of this member as a "pointer to member"
2984 type. If INTYPE is non-null, then it will be the type
2985 of the member we are looking for. This will help us resolve
2986 "pointers to member functions". This function is used
2987 to resolve user expressions of the form "DOMAIN::NAME". */
2988
2989 struct value *
2990 value_struct_elt_for_reference (struct type *domain, int offset,
2991 struct type *curtype, char *name,
2992 struct type *intype)
2993 {
2994 register struct type *t = curtype;
2995 register int i;
2996 struct value *v;
2997
2998 if (TYPE_CODE (t) != TYPE_CODE_STRUCT
2999 && TYPE_CODE (t) != TYPE_CODE_UNION)
3000 error ("Internal error: non-aggregate type to value_struct_elt_for_reference");
3001
3002 for (i = TYPE_NFIELDS (t) - 1; i >= TYPE_N_BASECLASSES (t); i--)
3003 {
3004 char *t_field_name = TYPE_FIELD_NAME (t, i);
3005
3006 if (t_field_name && STREQ (t_field_name, name))
3007 {
3008 if (TYPE_FIELD_STATIC (t, i))
3009 {
3010 v = value_static_field (t, i);
3011 if (v == NULL)
3012 error ("Internal error: could not find static variable %s",
3013 name);
3014 return v;
3015 }
3016 if (TYPE_FIELD_PACKED (t, i))
3017 error ("pointers to bitfield members not allowed");
3018
3019 return value_from_longest
3020 (lookup_reference_type (lookup_member_type (TYPE_FIELD_TYPE (t, i),
3021 domain)),
3022 offset + (LONGEST) (TYPE_FIELD_BITPOS (t, i) >> 3));
3023 }
3024 }
3025
3026 /* C++: If it was not found as a data field, then try to
3027 return it as a pointer to a method. */
3028
3029 /* Destructors are a special case. */
3030 if (destructor_name_p (name, t))
3031 {
3032 error ("member pointers to destructors not implemented yet");
3033 }
3034
3035 /* Perform all necessary dereferencing. */
3036 while (intype && TYPE_CODE (intype) == TYPE_CODE_PTR)
3037 intype = TYPE_TARGET_TYPE (intype);
3038
3039 for (i = TYPE_NFN_FIELDS (t) - 1; i >= 0; --i)
3040 {
3041 char *t_field_name = TYPE_FN_FIELDLIST_NAME (t, i);
3042 char dem_opname[64];
3043
3044 if (strncmp (t_field_name, "__", 2) == 0 ||
3045 strncmp (t_field_name, "op", 2) == 0 ||
3046 strncmp (t_field_name, "type", 4) == 0)
3047 {
3048 if (cplus_demangle_opname (t_field_name, dem_opname, DMGL_ANSI))
3049 t_field_name = dem_opname;
3050 else if (cplus_demangle_opname (t_field_name, dem_opname, 0))
3051 t_field_name = dem_opname;
3052 }
3053 if (t_field_name && STREQ (t_field_name, name))
3054 {
3055 int j = TYPE_FN_FIELDLIST_LENGTH (t, i);
3056 struct fn_field *f = TYPE_FN_FIELDLIST1 (t, i);
3057
3058 if (intype == 0 && j > 1)
3059 error ("non-unique member `%s' requires type instantiation", name);
3060 if (intype)
3061 {
3062 while (j--)
3063 if (TYPE_FN_FIELD_TYPE (f, j) == intype)
3064 break;
3065 if (j < 0)
3066 error ("no member function matches that type instantiation");
3067 }
3068 else
3069 j = 0;
3070
3071 if (TYPE_FN_FIELD_STUB (f, j))
3072 check_stub_method (t, i, j);
3073 if (TYPE_FN_FIELD_VIRTUAL_P (f, j))
3074 {
3075 return value_from_longest
3076 (lookup_reference_type
3077 (lookup_member_type (TYPE_FN_FIELD_TYPE (f, j),
3078 domain)),
3079 (LONGEST) METHOD_PTR_FROM_VOFFSET (TYPE_FN_FIELD_VOFFSET (f, j)));
3080 }
3081 else
3082 {
3083 struct symbol *s = lookup_symbol (TYPE_FN_FIELD_PHYSNAME (f, j),
3084 0, VAR_NAMESPACE, 0, NULL);
3085 if (s == NULL)
3086 {
3087 v = 0;
3088 }
3089 else
3090 {
3091 v = read_var_value (s, 0);
3092 #if 0
3093 VALUE_TYPE (v) = lookup_reference_type
3094 (lookup_member_type (TYPE_FN_FIELD_TYPE (f, j),
3095 domain));
3096 #endif
3097 }
3098 return v;
3099 }
3100 }
3101 }
3102 for (i = TYPE_N_BASECLASSES (t) - 1; i >= 0; i--)
3103 {
3104 struct value *v;
3105 int base_offset;
3106
3107 if (BASETYPE_VIA_VIRTUAL (t, i))
3108 base_offset = 0;
3109 else
3110 base_offset = TYPE_BASECLASS_BITPOS (t, i) / 8;
3111 v = value_struct_elt_for_reference (domain,
3112 offset + base_offset,
3113 TYPE_BASECLASS (t, i),
3114 name,
3115 intype);
3116 if (v)
3117 return v;
3118 }
3119 return 0;
3120 }
3121
3122
3123 /* Given a pointer value V, find the real (RTTI) type
3124 of the object it points to.
3125 Other parameters FULL, TOP, USING_ENC as with value_rtti_type()
3126 and refer to the values computed for the object pointed to. */
3127
3128 struct type *
3129 value_rtti_target_type (struct value *v, int *full, int *top, int *using_enc)
3130 {
3131 struct value *target;
3132
3133 target = value_ind (v);
3134
3135 return value_rtti_type (target, full, top, using_enc);
3136 }
3137
3138 /* Given a value pointed to by ARGP, check its real run-time type, and
3139 if that is different from the enclosing type, create a new value
3140 using the real run-time type as the enclosing type (and of the same
3141 type as ARGP) and return it, with the embedded offset adjusted to
3142 be the correct offset to the enclosed object
3143 RTYPE is the type, and XFULL, XTOP, and XUSING_ENC are the other
3144 parameters, computed by value_rtti_type(). If these are available,
3145 they can be supplied and a second call to value_rtti_type() is avoided.
3146 (Pass RTYPE == NULL if they're not available */
3147
3148 struct value *
3149 value_full_object (struct value *argp, struct type *rtype, int xfull, int xtop,
3150 int xusing_enc)
3151 {
3152 struct type *real_type;
3153 int full = 0;
3154 int top = -1;
3155 int using_enc = 0;
3156 struct value *new_val;
3157
3158 if (rtype)
3159 {
3160 real_type = rtype;
3161 full = xfull;
3162 top = xtop;
3163 using_enc = xusing_enc;
3164 }
3165 else
3166 real_type = value_rtti_type (argp, &full, &top, &using_enc);
3167
3168 /* If no RTTI data, or if object is already complete, do nothing */
3169 if (!real_type || real_type == VALUE_ENCLOSING_TYPE (argp))
3170 return argp;
3171
3172 /* If we have the full object, but for some reason the enclosing
3173 type is wrong, set it *//* pai: FIXME -- sounds iffy */
3174 if (full)
3175 {
3176 argp = value_change_enclosing_type (argp, real_type);
3177 return argp;
3178 }
3179
3180 /* Check if object is in memory */
3181 if (VALUE_LVAL (argp) != lval_memory)
3182 {
3183 warning ("Couldn't retrieve complete object of RTTI type %s; object may be in register(s).", TYPE_NAME (real_type));
3184
3185 return argp;
3186 }
3187
3188 /* All other cases -- retrieve the complete object */
3189 /* Go back by the computed top_offset from the beginning of the object,
3190 adjusting for the embedded offset of argp if that's what value_rtti_type
3191 used for its computation. */
3192 new_val = value_at_lazy (real_type, VALUE_ADDRESS (argp) - top +
3193 (using_enc ? 0 : VALUE_EMBEDDED_OFFSET (argp)),
3194 VALUE_BFD_SECTION (argp));
3195 VALUE_TYPE (new_val) = VALUE_TYPE (argp);
3196 VALUE_EMBEDDED_OFFSET (new_val) = using_enc ? top + VALUE_EMBEDDED_OFFSET (argp) : top;
3197 return new_val;
3198 }
3199
3200
3201
3202
3203 /* C++: return the value of the class instance variable, if one exists.
3204 Flag COMPLAIN signals an error if the request is made in an
3205 inappropriate context. */
3206
3207 struct value *
3208 value_of_this (int complain)
3209 {
3210 struct symbol *func, *sym;
3211 struct block *b;
3212 int i;
3213 static const char funny_this[] = "this";
3214 struct value *this;
3215
3216 if (selected_frame == 0)
3217 {
3218 if (complain)
3219 error ("no frame selected");
3220 else
3221 return 0;
3222 }
3223
3224 func = get_frame_function (selected_frame);
3225 if (!func)
3226 {
3227 if (complain)
3228 error ("no `this' in nameless context");
3229 else
3230 return 0;
3231 }
3232
3233 b = SYMBOL_BLOCK_VALUE (func);
3234 i = BLOCK_NSYMS (b);
3235 if (i <= 0)
3236 {
3237 if (complain)
3238 error ("no args, no `this'");
3239 else
3240 return 0;
3241 }
3242
3243 /* Calling lookup_block_symbol is necessary to get the LOC_REGISTER
3244 symbol instead of the LOC_ARG one (if both exist). */
3245 sym = lookup_block_symbol (b, funny_this, VAR_NAMESPACE);
3246 if (sym == NULL)
3247 {
3248 if (complain)
3249 error ("current stack frame not in method");
3250 else
3251 return NULL;
3252 }
3253
3254 this = read_var_value (sym, selected_frame);
3255 if (this == 0 && complain)
3256 error ("`this' argument at unknown address");
3257 return this;
3258 }
3259
3260 /* Create a slice (sub-string, sub-array) of ARRAY, that is LENGTH elements
3261 long, starting at LOWBOUND. The result has the same lower bound as
3262 the original ARRAY. */
3263
3264 struct value *
3265 value_slice (struct value *array, int lowbound, int length)
3266 {
3267 struct type *slice_range_type, *slice_type, *range_type;
3268 LONGEST lowerbound, upperbound, offset;
3269 struct value *slice;
3270 struct type *array_type;
3271 array_type = check_typedef (VALUE_TYPE (array));
3272 COERCE_VARYING_ARRAY (array, array_type);
3273 if (TYPE_CODE (array_type) != TYPE_CODE_ARRAY
3274 && TYPE_CODE (array_type) != TYPE_CODE_STRING
3275 && TYPE_CODE (array_type) != TYPE_CODE_BITSTRING)
3276 error ("cannot take slice of non-array");
3277 range_type = TYPE_INDEX_TYPE (array_type);
3278 if (get_discrete_bounds (range_type, &lowerbound, &upperbound) < 0)
3279 error ("slice from bad array or bitstring");
3280 if (lowbound < lowerbound || length < 0
3281 || lowbound + length - 1 > upperbound
3282 /* Chill allows zero-length strings but not arrays. */
3283 || (current_language->la_language == language_chill
3284 && length == 0 && TYPE_CODE (array_type) == TYPE_CODE_ARRAY))
3285 error ("slice out of range");
3286 /* FIXME-type-allocation: need a way to free this type when we are
3287 done with it. */
3288 slice_range_type = create_range_type ((struct type *) NULL,
3289 TYPE_TARGET_TYPE (range_type),
3290 lowbound, lowbound + length - 1);
3291 if (TYPE_CODE (array_type) == TYPE_CODE_BITSTRING)
3292 {
3293 int i;
3294 slice_type = create_set_type ((struct type *) NULL, slice_range_type);
3295 TYPE_CODE (slice_type) = TYPE_CODE_BITSTRING;
3296 slice = value_zero (slice_type, not_lval);
3297 for (i = 0; i < length; i++)
3298 {
3299 int element = value_bit_index (array_type,
3300 VALUE_CONTENTS (array),
3301 lowbound + i);
3302 if (element < 0)
3303 error ("internal error accessing bitstring");
3304 else if (element > 0)
3305 {
3306 int j = i % TARGET_CHAR_BIT;
3307 if (BITS_BIG_ENDIAN)
3308 j = TARGET_CHAR_BIT - 1 - j;
3309 VALUE_CONTENTS_RAW (slice)[i / TARGET_CHAR_BIT] |= (1 << j);
3310 }
3311 }
3312 /* We should set the address, bitssize, and bitspos, so the clice
3313 can be used on the LHS, but that may require extensions to
3314 value_assign. For now, just leave as a non_lval. FIXME. */
3315 }
3316 else
3317 {
3318 struct type *element_type = TYPE_TARGET_TYPE (array_type);
3319 offset
3320 = (lowbound - lowerbound) * TYPE_LENGTH (check_typedef (element_type));
3321 slice_type = create_array_type ((struct type *) NULL, element_type,
3322 slice_range_type);
3323 TYPE_CODE (slice_type) = TYPE_CODE (array_type);
3324 slice = allocate_value (slice_type);
3325 if (VALUE_LAZY (array))
3326 VALUE_LAZY (slice) = 1;
3327 else
3328 memcpy (VALUE_CONTENTS (slice), VALUE_CONTENTS (array) + offset,
3329 TYPE_LENGTH (slice_type));
3330 if (VALUE_LVAL (array) == lval_internalvar)
3331 VALUE_LVAL (slice) = lval_internalvar_component;
3332 else
3333 VALUE_LVAL (slice) = VALUE_LVAL (array);
3334 VALUE_ADDRESS (slice) = VALUE_ADDRESS (array);
3335 VALUE_OFFSET (slice) = VALUE_OFFSET (array) + offset;
3336 }
3337 return slice;
3338 }
3339
3340 /* Assuming chill_varying_type (VARRAY) is true, return an equivalent
3341 value as a fixed-length array. */
3342
3343 struct value *
3344 varying_to_slice (struct value *varray)
3345 {
3346 struct type *vtype = check_typedef (VALUE_TYPE (varray));
3347 LONGEST length = unpack_long (TYPE_FIELD_TYPE (vtype, 0),
3348 VALUE_CONTENTS (varray)
3349 + TYPE_FIELD_BITPOS (vtype, 0) / 8);
3350 return value_slice (value_primitive_field (varray, 0, 1, vtype), 0, length);
3351 }
3352
3353 /* Create a value for a FORTRAN complex number. Currently most of
3354 the time values are coerced to COMPLEX*16 (i.e. a complex number
3355 composed of 2 doubles. This really should be a smarter routine
3356 that figures out precision inteligently as opposed to assuming
3357 doubles. FIXME: fmb */
3358
3359 struct value *
3360 value_literal_complex (struct value *arg1, struct value *arg2, struct type *type)
3361 {
3362 struct value *val;
3363 struct type *real_type = TYPE_TARGET_TYPE (type);
3364
3365 val = allocate_value (type);
3366 arg1 = value_cast (real_type, arg1);
3367 arg2 = value_cast (real_type, arg2);
3368
3369 memcpy (VALUE_CONTENTS_RAW (val),
3370 VALUE_CONTENTS (arg1), TYPE_LENGTH (real_type));
3371 memcpy (VALUE_CONTENTS_RAW (val) + TYPE_LENGTH (real_type),
3372 VALUE_CONTENTS (arg2), TYPE_LENGTH (real_type));
3373 return val;
3374 }
3375
3376 /* Cast a value into the appropriate complex data type. */
3377
3378 static struct value *
3379 cast_into_complex (struct type *type, struct value *val)
3380 {
3381 struct type *real_type = TYPE_TARGET_TYPE (type);
3382 if (TYPE_CODE (VALUE_TYPE (val)) == TYPE_CODE_COMPLEX)
3383 {
3384 struct type *val_real_type = TYPE_TARGET_TYPE (VALUE_TYPE (val));
3385 struct value *re_val = allocate_value (val_real_type);
3386 struct value *im_val = allocate_value (val_real_type);
3387
3388 memcpy (VALUE_CONTENTS_RAW (re_val),
3389 VALUE_CONTENTS (val), TYPE_LENGTH (val_real_type));
3390 memcpy (VALUE_CONTENTS_RAW (im_val),
3391 VALUE_CONTENTS (val) + TYPE_LENGTH (val_real_type),
3392 TYPE_LENGTH (val_real_type));
3393
3394 return value_literal_complex (re_val, im_val, type);
3395 }
3396 else if (TYPE_CODE (VALUE_TYPE (val)) == TYPE_CODE_FLT
3397 || TYPE_CODE (VALUE_TYPE (val)) == TYPE_CODE_INT)
3398 return value_literal_complex (val, value_zero (real_type, not_lval), type);
3399 else
3400 error ("cannot cast non-number to complex");
3401 }
3402
3403 void
3404 _initialize_valops (void)
3405 {
3406 #if 0
3407 add_show_from_set
3408 (add_set_cmd ("abandon", class_support, var_boolean, (char *) &auto_abandon,
3409 "Set automatic abandonment of expressions upon failure.",
3410 &setlist),
3411 &showlist);
3412 #endif
3413
3414 add_show_from_set
3415 (add_set_cmd ("overload-resolution", class_support, var_boolean, (char *) &overload_resolution,
3416 "Set overload resolution in evaluating C++ functions.",
3417 &setlist),
3418 &showlist);
3419 overload_resolution = 1;
3420
3421 add_show_from_set (
3422 add_set_cmd ("unwindonsignal", no_class, var_boolean,
3423 (char *) &unwind_on_signal_p,
3424 "Set unwinding of stack if a signal is received while in a call dummy.\n\
3425 The unwindonsignal lets the user determine what gdb should do if a signal\n\
3426 is received while in a function called from gdb (call dummy). If set, gdb\n\
3427 unwinds the stack and restore the context to what as it was before the call.\n\
3428 The default is to stop in the frame where the signal was received.", &setlist),
3429 &showlist);
3430 }
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