Rewrite xcoff*_ppc_relocate_section.
[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 (int) 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 (int) 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 /* FIXME (alloca): Not safe for very large data types. */
701 char *buffer = (char *) alloca (amount_to_copy
702 + sizeof (LONGEST)
703 + MAX_REGISTER_RAW_SIZE);
704
705 int regno;
706 struct frame_info *frame;
707
708 /* Figure out which frame this is in currently. */
709 for (frame = get_current_frame ();
710 frame && FRAME_FP (frame) != VALUE_FRAME (toval);
711 frame = get_prev_frame (frame))
712 ;
713
714 if (!frame)
715 error ("Value being assigned to is no longer active.");
716
717 amount_to_copy += (reg_size - amount_to_copy % reg_size);
718
719 /* Copy it out. */
720 for ((regno = VALUE_FRAME_REGNUM (toval) + reg_offset,
721 amount_copied = 0);
722 amount_copied < amount_to_copy;
723 amount_copied += reg_size, regno++)
724 {
725 get_saved_register (buffer + amount_copied,
726 (int *) NULL, (CORE_ADDR *) NULL,
727 frame, regno, (enum lval_type *) NULL);
728 }
729
730 /* Modify what needs to be modified. */
731 if (VALUE_BITSIZE (toval))
732 modify_field (buffer + byte_offset,
733 value_as_long (fromval),
734 VALUE_BITPOS (toval), VALUE_BITSIZE (toval));
735 else if (use_buffer)
736 memcpy (buffer + byte_offset, raw_buffer, use_buffer);
737 else
738 memcpy (buffer + byte_offset, VALUE_CONTENTS (fromval),
739 TYPE_LENGTH (type));
740
741 /* Copy it back. */
742 for ((regno = VALUE_FRAME_REGNUM (toval) + reg_offset,
743 amount_copied = 0);
744 amount_copied < amount_to_copy;
745 amount_copied += reg_size, regno++)
746 {
747 enum lval_type lval;
748 CORE_ADDR addr;
749 int optim;
750
751 /* Just find out where to put it. */
752 get_saved_register ((char *) NULL,
753 &optim, &addr, frame, regno, &lval);
754
755 if (optim)
756 error ("Attempt to assign to a value that was optimized out.");
757 if (lval == lval_memory)
758 write_memory (addr, buffer + amount_copied, reg_size);
759 else if (lval == lval_register)
760 write_register_bytes (addr, buffer + amount_copied, reg_size);
761 else
762 error ("Attempt to assign to an unmodifiable value.");
763 }
764
765 if (register_changed_hook)
766 register_changed_hook (-1);
767 }
768 break;
769
770
771 default:
772 error ("Left operand of assignment is not an lvalue.");
773 }
774
775 /* If the field does not entirely fill a LONGEST, then zero the sign bits.
776 If the field is signed, and is negative, then sign extend. */
777 if ((VALUE_BITSIZE (toval) > 0)
778 && (VALUE_BITSIZE (toval) < 8 * (int) sizeof (LONGEST)))
779 {
780 LONGEST fieldval = value_as_long (fromval);
781 LONGEST valmask = (((ULONGEST) 1) << VALUE_BITSIZE (toval)) - 1;
782
783 fieldval &= valmask;
784 if (!TYPE_UNSIGNED (type) && (fieldval & (valmask ^ (valmask >> 1))))
785 fieldval |= ~valmask;
786
787 fromval = value_from_longest (type, fieldval);
788 }
789
790 val = value_copy (toval);
791 memcpy (VALUE_CONTENTS_RAW (val), VALUE_CONTENTS (fromval),
792 TYPE_LENGTH (type));
793 VALUE_TYPE (val) = type;
794 val = value_change_enclosing_type (val, VALUE_ENCLOSING_TYPE (fromval));
795 VALUE_EMBEDDED_OFFSET (val) = VALUE_EMBEDDED_OFFSET (fromval);
796 VALUE_POINTED_TO_OFFSET (val) = VALUE_POINTED_TO_OFFSET (fromval);
797
798 return val;
799 }
800
801 /* Extend a value VAL to COUNT repetitions of its type. */
802
803 struct value *
804 value_repeat (struct value *arg1, int count)
805 {
806 struct value *val;
807
808 if (VALUE_LVAL (arg1) != lval_memory)
809 error ("Only values in memory can be extended with '@'.");
810 if (count < 1)
811 error ("Invalid number %d of repetitions.", count);
812
813 val = allocate_repeat_value (VALUE_ENCLOSING_TYPE (arg1), count);
814
815 read_memory (VALUE_ADDRESS (arg1) + VALUE_OFFSET (arg1),
816 VALUE_CONTENTS_ALL_RAW (val),
817 TYPE_LENGTH (VALUE_ENCLOSING_TYPE (val)));
818 VALUE_LVAL (val) = lval_memory;
819 VALUE_ADDRESS (val) = VALUE_ADDRESS (arg1) + VALUE_OFFSET (arg1);
820
821 return val;
822 }
823
824 struct value *
825 value_of_variable (struct symbol *var, struct block *b)
826 {
827 struct value *val;
828 struct frame_info *frame = NULL;
829
830 if (!b)
831 frame = NULL; /* Use selected frame. */
832 else if (symbol_read_needs_frame (var))
833 {
834 frame = block_innermost_frame (b);
835 if (!frame)
836 {
837 if (BLOCK_FUNCTION (b)
838 && SYMBOL_SOURCE_NAME (BLOCK_FUNCTION (b)))
839 error ("No frame is currently executing in block %s.",
840 SYMBOL_SOURCE_NAME (BLOCK_FUNCTION (b)));
841 else
842 error ("No frame is currently executing in specified block");
843 }
844 }
845
846 val = read_var_value (var, frame);
847 if (!val)
848 error ("Address of symbol \"%s\" is unknown.", SYMBOL_SOURCE_NAME (var));
849
850 return val;
851 }
852
853 /* Given a value which is an array, return a value which is a pointer to its
854 first element, regardless of whether or not the array has a nonzero lower
855 bound.
856
857 FIXME: A previous comment here indicated that this routine should be
858 substracting the array's lower bound. It's not clear to me that this
859 is correct. Given an array subscripting operation, it would certainly
860 work to do the adjustment here, essentially computing:
861
862 (&array[0] - (lowerbound * sizeof array[0])) + (index * sizeof array[0])
863
864 However I believe a more appropriate and logical place to account for
865 the lower bound is to do so in value_subscript, essentially computing:
866
867 (&array[0] + ((index - lowerbound) * sizeof array[0]))
868
869 As further evidence consider what would happen with operations other
870 than array subscripting, where the caller would get back a value that
871 had an address somewhere before the actual first element of the array,
872 and the information about the lower bound would be lost because of
873 the coercion to pointer type.
874 */
875
876 struct value *
877 value_coerce_array (struct value *arg1)
878 {
879 register struct type *type = check_typedef (VALUE_TYPE (arg1));
880
881 if (VALUE_LVAL (arg1) != lval_memory)
882 error ("Attempt to take address of value not located in memory.");
883
884 return value_from_pointer (lookup_pointer_type (TYPE_TARGET_TYPE (type)),
885 (VALUE_ADDRESS (arg1) + VALUE_OFFSET (arg1)));
886 }
887
888 /* Given a value which is a function, return a value which is a pointer
889 to it. */
890
891 struct value *
892 value_coerce_function (struct value *arg1)
893 {
894 struct value *retval;
895
896 if (VALUE_LVAL (arg1) != lval_memory)
897 error ("Attempt to take address of value not located in memory.");
898
899 retval = value_from_pointer (lookup_pointer_type (VALUE_TYPE (arg1)),
900 (VALUE_ADDRESS (arg1) + VALUE_OFFSET (arg1)));
901 VALUE_BFD_SECTION (retval) = VALUE_BFD_SECTION (arg1);
902 return retval;
903 }
904
905 /* Return a pointer value for the object for which ARG1 is the contents. */
906
907 struct value *
908 value_addr (struct value *arg1)
909 {
910 struct value *arg2;
911
912 struct type *type = check_typedef (VALUE_TYPE (arg1));
913 if (TYPE_CODE (type) == TYPE_CODE_REF)
914 {
915 /* Copy the value, but change the type from (T&) to (T*).
916 We keep the same location information, which is efficient,
917 and allows &(&X) to get the location containing the reference. */
918 arg2 = value_copy (arg1);
919 VALUE_TYPE (arg2) = lookup_pointer_type (TYPE_TARGET_TYPE (type));
920 return arg2;
921 }
922 if (TYPE_CODE (type) == TYPE_CODE_FUNC)
923 return value_coerce_function (arg1);
924
925 if (VALUE_LVAL (arg1) != lval_memory)
926 error ("Attempt to take address of value not located in memory.");
927
928 /* Get target memory address */
929 arg2 = value_from_pointer (lookup_pointer_type (VALUE_TYPE (arg1)),
930 (VALUE_ADDRESS (arg1)
931 + VALUE_OFFSET (arg1)
932 + VALUE_EMBEDDED_OFFSET (arg1)));
933
934 /* This may be a pointer to a base subobject; so remember the
935 full derived object's type ... */
936 arg2 = value_change_enclosing_type (arg2, lookup_pointer_type (VALUE_ENCLOSING_TYPE (arg1)));
937 /* ... and also the relative position of the subobject in the full object */
938 VALUE_POINTED_TO_OFFSET (arg2) = VALUE_EMBEDDED_OFFSET (arg1);
939 VALUE_BFD_SECTION (arg2) = VALUE_BFD_SECTION (arg1);
940 return arg2;
941 }
942
943 /* Given a value of a pointer type, apply the C unary * operator to it. */
944
945 struct value *
946 value_ind (struct value *arg1)
947 {
948 struct type *base_type;
949 struct value *arg2;
950
951 COERCE_ARRAY (arg1);
952
953 base_type = check_typedef (VALUE_TYPE (arg1));
954
955 if (TYPE_CODE (base_type) == TYPE_CODE_MEMBER)
956 error ("not implemented: member types in value_ind");
957
958 /* Allow * on an integer so we can cast it to whatever we want.
959 This returns an int, which seems like the most C-like thing
960 to do. "long long" variables are rare enough that
961 BUILTIN_TYPE_LONGEST would seem to be a mistake. */
962 if (TYPE_CODE (base_type) == TYPE_CODE_INT)
963 return value_at (builtin_type_int,
964 (CORE_ADDR) value_as_long (arg1),
965 VALUE_BFD_SECTION (arg1));
966 else if (TYPE_CODE (base_type) == TYPE_CODE_PTR)
967 {
968 struct type *enc_type;
969 /* We may be pointing to something embedded in a larger object */
970 /* Get the real type of the enclosing object */
971 enc_type = check_typedef (VALUE_ENCLOSING_TYPE (arg1));
972 enc_type = TYPE_TARGET_TYPE (enc_type);
973 /* Retrieve the enclosing object pointed to */
974 arg2 = value_at_lazy (enc_type,
975 value_as_address (arg1) - VALUE_POINTED_TO_OFFSET (arg1),
976 VALUE_BFD_SECTION (arg1));
977 /* Re-adjust type */
978 VALUE_TYPE (arg2) = TYPE_TARGET_TYPE (base_type);
979 /* Add embedding info */
980 arg2 = value_change_enclosing_type (arg2, enc_type);
981 VALUE_EMBEDDED_OFFSET (arg2) = VALUE_POINTED_TO_OFFSET (arg1);
982
983 /* We may be pointing to an object of some derived type */
984 arg2 = value_full_object (arg2, NULL, 0, 0, 0);
985 return arg2;
986 }
987
988 error ("Attempt to take contents of a non-pointer value.");
989 return 0; /* For lint -- never reached */
990 }
991 \f
992 /* Pushing small parts of stack frames. */
993
994 /* Push one word (the size of object that a register holds). */
995
996 CORE_ADDR
997 push_word (CORE_ADDR sp, ULONGEST word)
998 {
999 register int len = REGISTER_SIZE;
1000 char *buffer = alloca (MAX_REGISTER_RAW_SIZE);
1001
1002 store_unsigned_integer (buffer, len, word);
1003 if (INNER_THAN (1, 2))
1004 {
1005 /* stack grows downward */
1006 sp -= len;
1007 write_memory (sp, buffer, len);
1008 }
1009 else
1010 {
1011 /* stack grows upward */
1012 write_memory (sp, buffer, len);
1013 sp += len;
1014 }
1015
1016 return sp;
1017 }
1018
1019 /* Push LEN bytes with data at BUFFER. */
1020
1021 CORE_ADDR
1022 push_bytes (CORE_ADDR sp, char *buffer, int len)
1023 {
1024 if (INNER_THAN (1, 2))
1025 {
1026 /* stack grows downward */
1027 sp -= len;
1028 write_memory (sp, buffer, len);
1029 }
1030 else
1031 {
1032 /* stack grows upward */
1033 write_memory (sp, buffer, len);
1034 sp += len;
1035 }
1036
1037 return sp;
1038 }
1039
1040 #ifndef PARM_BOUNDARY
1041 #define PARM_BOUNDARY (0)
1042 #endif
1043
1044 /* Push onto the stack the specified value VALUE. Pad it correctly for
1045 it to be an argument to a function. */
1046
1047 static CORE_ADDR
1048 value_push (register CORE_ADDR sp, struct value *arg)
1049 {
1050 register int len = TYPE_LENGTH (VALUE_ENCLOSING_TYPE (arg));
1051 register int container_len = len;
1052 register int offset;
1053
1054 /* How big is the container we're going to put this value in? */
1055 if (PARM_BOUNDARY)
1056 container_len = ((len + PARM_BOUNDARY / TARGET_CHAR_BIT - 1)
1057 & ~(PARM_BOUNDARY / TARGET_CHAR_BIT - 1));
1058
1059 /* Are we going to put it at the high or low end of the container? */
1060 if (TARGET_BYTE_ORDER == BFD_ENDIAN_BIG)
1061 offset = container_len - len;
1062 else
1063 offset = 0;
1064
1065 if (INNER_THAN (1, 2))
1066 {
1067 /* stack grows downward */
1068 sp -= container_len;
1069 write_memory (sp + offset, VALUE_CONTENTS_ALL (arg), len);
1070 }
1071 else
1072 {
1073 /* stack grows upward */
1074 write_memory (sp + offset, VALUE_CONTENTS_ALL (arg), len);
1075 sp += container_len;
1076 }
1077
1078 return sp;
1079 }
1080
1081 CORE_ADDR
1082 default_push_arguments (int nargs, struct value **args, CORE_ADDR sp,
1083 int struct_return, CORE_ADDR struct_addr)
1084 {
1085 /* ASSERT ( !struct_return); */
1086 int i;
1087 for (i = nargs - 1; i >= 0; i--)
1088 sp = value_push (sp, args[i]);
1089 return sp;
1090 }
1091
1092
1093 /* Functions to use for the COERCE_FLOAT_TO_DOUBLE gdbarch method.
1094
1095 How you should pass arguments to a function depends on whether it
1096 was defined in K&R style or prototype style. If you define a
1097 function using the K&R syntax that takes a `float' argument, then
1098 callers must pass that argument as a `double'. If you define the
1099 function using the prototype syntax, then you must pass the
1100 argument as a `float', with no promotion.
1101
1102 Unfortunately, on certain older platforms, the debug info doesn't
1103 indicate reliably how each function was defined. A function type's
1104 TYPE_FLAG_PROTOTYPED flag may be clear, even if the function was
1105 defined in prototype style. When calling a function whose
1106 TYPE_FLAG_PROTOTYPED flag is clear, GDB consults the
1107 COERCE_FLOAT_TO_DOUBLE gdbarch method to decide what to do.
1108
1109 For modern targets, it is proper to assume that, if the prototype
1110 flag is clear, that can be trusted: `float' arguments should be
1111 promoted to `double'. You should register the function
1112 `standard_coerce_float_to_double' to get this behavior.
1113
1114 For some older targets, if the prototype flag is clear, that
1115 doesn't tell us anything. So we guess that, if we don't have a
1116 type for the formal parameter (i.e., the first argument to
1117 COERCE_FLOAT_TO_DOUBLE is null), then we should promote it;
1118 otherwise, we should leave it alone. The function
1119 `default_coerce_float_to_double' provides this behavior; it is the
1120 default value, for compatibility with older configurations. */
1121 int
1122 default_coerce_float_to_double (struct type *formal, struct type *actual)
1123 {
1124 return formal == NULL;
1125 }
1126
1127
1128 int
1129 standard_coerce_float_to_double (struct type *formal, struct type *actual)
1130 {
1131 return 1;
1132 }
1133
1134
1135 /* Perform the standard coercions that are specified
1136 for arguments to be passed to C functions.
1137
1138 If PARAM_TYPE is non-NULL, it is the expected parameter type.
1139 IS_PROTOTYPED is non-zero if the function declaration is prototyped. */
1140
1141 static struct value *
1142 value_arg_coerce (struct value *arg, struct type *param_type,
1143 int is_prototyped)
1144 {
1145 register struct type *arg_type = check_typedef (VALUE_TYPE (arg));
1146 register struct type *type
1147 = param_type ? check_typedef (param_type) : arg_type;
1148
1149 switch (TYPE_CODE (type))
1150 {
1151 case TYPE_CODE_REF:
1152 if (TYPE_CODE (arg_type) != TYPE_CODE_REF
1153 && TYPE_CODE (arg_type) != TYPE_CODE_PTR)
1154 {
1155 arg = value_addr (arg);
1156 VALUE_TYPE (arg) = param_type;
1157 return arg;
1158 }
1159 break;
1160 case TYPE_CODE_INT:
1161 case TYPE_CODE_CHAR:
1162 case TYPE_CODE_BOOL:
1163 case TYPE_CODE_ENUM:
1164 /* If we don't have a prototype, coerce to integer type if necessary. */
1165 if (!is_prototyped)
1166 {
1167 if (TYPE_LENGTH (type) < TYPE_LENGTH (builtin_type_int))
1168 type = builtin_type_int;
1169 }
1170 /* Currently all target ABIs require at least the width of an integer
1171 type for an argument. We may have to conditionalize the following
1172 type coercion for future targets. */
1173 if (TYPE_LENGTH (type) < TYPE_LENGTH (builtin_type_int))
1174 type = builtin_type_int;
1175 break;
1176 case TYPE_CODE_FLT:
1177 /* FIXME: We should always convert floats to doubles in the
1178 non-prototyped case. As many debugging formats include
1179 no information about prototyping, we have to live with
1180 COERCE_FLOAT_TO_DOUBLE for now. */
1181 if (!is_prototyped && COERCE_FLOAT_TO_DOUBLE (param_type, arg_type))
1182 {
1183 if (TYPE_LENGTH (type) < TYPE_LENGTH (builtin_type_double))
1184 type = builtin_type_double;
1185 else if (TYPE_LENGTH (type) > TYPE_LENGTH (builtin_type_double))
1186 type = builtin_type_long_double;
1187 }
1188 break;
1189 case TYPE_CODE_FUNC:
1190 type = lookup_pointer_type (type);
1191 break;
1192 case TYPE_CODE_ARRAY:
1193 if (current_language->c_style_arrays)
1194 type = lookup_pointer_type (TYPE_TARGET_TYPE (type));
1195 break;
1196 case TYPE_CODE_UNDEF:
1197 case TYPE_CODE_PTR:
1198 case TYPE_CODE_STRUCT:
1199 case TYPE_CODE_UNION:
1200 case TYPE_CODE_VOID:
1201 case TYPE_CODE_SET:
1202 case TYPE_CODE_RANGE:
1203 case TYPE_CODE_STRING:
1204 case TYPE_CODE_BITSTRING:
1205 case TYPE_CODE_ERROR:
1206 case TYPE_CODE_MEMBER:
1207 case TYPE_CODE_METHOD:
1208 case TYPE_CODE_COMPLEX:
1209 default:
1210 break;
1211 }
1212
1213 return value_cast (type, arg);
1214 }
1215
1216 /* Determine a function's address and its return type from its value.
1217 Calls error() if the function is not valid for calling. */
1218
1219 static CORE_ADDR
1220 find_function_addr (struct value *function, struct type **retval_type)
1221 {
1222 register struct type *ftype = check_typedef (VALUE_TYPE (function));
1223 register enum type_code code = TYPE_CODE (ftype);
1224 struct type *value_type;
1225 CORE_ADDR funaddr;
1226
1227 /* If it's a member function, just look at the function
1228 part of it. */
1229
1230 /* Determine address to call. */
1231 if (code == TYPE_CODE_FUNC || code == TYPE_CODE_METHOD)
1232 {
1233 funaddr = VALUE_ADDRESS (function);
1234 value_type = TYPE_TARGET_TYPE (ftype);
1235 }
1236 else if (code == TYPE_CODE_PTR)
1237 {
1238 funaddr = value_as_address (function);
1239 ftype = check_typedef (TYPE_TARGET_TYPE (ftype));
1240 if (TYPE_CODE (ftype) == TYPE_CODE_FUNC
1241 || TYPE_CODE (ftype) == TYPE_CODE_METHOD)
1242 {
1243 funaddr = CONVERT_FROM_FUNC_PTR_ADDR (funaddr);
1244 value_type = TYPE_TARGET_TYPE (ftype);
1245 }
1246 else
1247 value_type = builtin_type_int;
1248 }
1249 else if (code == TYPE_CODE_INT)
1250 {
1251 /* Handle the case of functions lacking debugging info.
1252 Their values are characters since their addresses are char */
1253 if (TYPE_LENGTH (ftype) == 1)
1254 funaddr = value_as_address (value_addr (function));
1255 else
1256 /* Handle integer used as address of a function. */
1257 funaddr = (CORE_ADDR) value_as_long (function);
1258
1259 value_type = builtin_type_int;
1260 }
1261 else
1262 error ("Invalid data type for function to be called.");
1263
1264 *retval_type = value_type;
1265 return funaddr;
1266 }
1267
1268 /* All this stuff with a dummy frame may seem unnecessarily complicated
1269 (why not just save registers in GDB?). The purpose of pushing a dummy
1270 frame which looks just like a real frame is so that if you call a
1271 function and then hit a breakpoint (get a signal, etc), "backtrace"
1272 will look right. Whether the backtrace needs to actually show the
1273 stack at the time the inferior function was called is debatable, but
1274 it certainly needs to not display garbage. So if you are contemplating
1275 making dummy frames be different from normal frames, consider that. */
1276
1277 /* Perform a function call in the inferior.
1278 ARGS is a vector of values of arguments (NARGS of them).
1279 FUNCTION is a value, the function to be called.
1280 Returns a value representing what the function returned.
1281 May fail to return, if a breakpoint or signal is hit
1282 during the execution of the function.
1283
1284 ARGS is modified to contain coerced values. */
1285
1286 static struct value *
1287 hand_function_call (struct value *function, int nargs, struct value **args)
1288 {
1289 register CORE_ADDR sp;
1290 register int i;
1291 int rc;
1292 CORE_ADDR start_sp;
1293 /* CALL_DUMMY is an array of words (REGISTER_SIZE), but each word
1294 is in host byte order. Before calling FIX_CALL_DUMMY, we byteswap it
1295 and remove any extra bytes which might exist because ULONGEST is
1296 bigger than REGISTER_SIZE.
1297
1298 NOTE: This is pretty wierd, as the call dummy is actually a
1299 sequence of instructions. But CISC machines will have
1300 to pack the instructions into REGISTER_SIZE units (and
1301 so will RISC machines for which INSTRUCTION_SIZE is not
1302 REGISTER_SIZE).
1303
1304 NOTE: This is pretty stupid. CALL_DUMMY should be in strict
1305 target byte order. */
1306
1307 static ULONGEST *dummy;
1308 int sizeof_dummy1;
1309 char *dummy1;
1310 CORE_ADDR old_sp;
1311 struct type *value_type;
1312 unsigned char struct_return;
1313 CORE_ADDR struct_addr = 0;
1314 struct inferior_status *inf_status;
1315 struct cleanup *old_chain;
1316 CORE_ADDR funaddr;
1317 int using_gcc; /* Set to version of gcc in use, or zero if not gcc */
1318 CORE_ADDR real_pc;
1319 struct type *param_type = NULL;
1320 struct type *ftype = check_typedef (SYMBOL_TYPE (function));
1321 int n_method_args = 0;
1322
1323 dummy = alloca (SIZEOF_CALL_DUMMY_WORDS);
1324 sizeof_dummy1 = REGISTER_SIZE * SIZEOF_CALL_DUMMY_WORDS / sizeof (ULONGEST);
1325 dummy1 = alloca (sizeof_dummy1);
1326 memcpy (dummy, CALL_DUMMY_WORDS, SIZEOF_CALL_DUMMY_WORDS);
1327
1328 if (!target_has_execution)
1329 noprocess ();
1330
1331 inf_status = save_inferior_status (1);
1332 old_chain = make_cleanup_restore_inferior_status (inf_status);
1333
1334 /* PUSH_DUMMY_FRAME is responsible for saving the inferior registers
1335 (and POP_FRAME for restoring them). (At least on most machines)
1336 they are saved on the stack in the inferior. */
1337 PUSH_DUMMY_FRAME;
1338
1339 old_sp = sp = read_sp ();
1340
1341 if (INNER_THAN (1, 2))
1342 {
1343 /* Stack grows down */
1344 sp -= sizeof_dummy1;
1345 start_sp = sp;
1346 }
1347 else
1348 {
1349 /* Stack grows up */
1350 start_sp = sp;
1351 sp += sizeof_dummy1;
1352 }
1353
1354 funaddr = find_function_addr (function, &value_type);
1355 CHECK_TYPEDEF (value_type);
1356
1357 {
1358 struct block *b = block_for_pc (funaddr);
1359 /* If compiled without -g, assume GCC 2. */
1360 using_gcc = (b == NULL ? 2 : BLOCK_GCC_COMPILED (b));
1361 }
1362
1363 /* Are we returning a value using a structure return or a normal
1364 value return? */
1365
1366 struct_return = using_struct_return (function, funaddr, value_type,
1367 using_gcc);
1368
1369 /* Create a call sequence customized for this function
1370 and the number of arguments for it. */
1371 for (i = 0; i < (int) (SIZEOF_CALL_DUMMY_WORDS / sizeof (dummy[0])); i++)
1372 store_unsigned_integer (&dummy1[i * REGISTER_SIZE],
1373 REGISTER_SIZE,
1374 (ULONGEST) dummy[i]);
1375
1376 #ifdef GDB_TARGET_IS_HPPA
1377 real_pc = FIX_CALL_DUMMY (dummy1, start_sp, funaddr, nargs, args,
1378 value_type, using_gcc);
1379 #else
1380 FIX_CALL_DUMMY (dummy1, start_sp, funaddr, nargs, args,
1381 value_type, using_gcc);
1382 real_pc = start_sp;
1383 #endif
1384
1385 if (CALL_DUMMY_LOCATION == ON_STACK)
1386 {
1387 write_memory (start_sp, (char *) dummy1, sizeof_dummy1);
1388 if (USE_GENERIC_DUMMY_FRAMES)
1389 generic_save_call_dummy_addr (start_sp, start_sp + sizeof_dummy1);
1390 }
1391
1392 if (CALL_DUMMY_LOCATION == BEFORE_TEXT_END)
1393 {
1394 /* Convex Unix prohibits executing in the stack segment. */
1395 /* Hope there is empty room at the top of the text segment. */
1396 extern CORE_ADDR text_end;
1397 static int checked = 0;
1398 if (!checked)
1399 for (start_sp = text_end - sizeof_dummy1; start_sp < text_end; ++start_sp)
1400 if (read_memory_integer (start_sp, 1) != 0)
1401 error ("text segment full -- no place to put call");
1402 checked = 1;
1403 sp = old_sp;
1404 real_pc = text_end - sizeof_dummy1;
1405 write_memory (real_pc, (char *) dummy1, sizeof_dummy1);
1406 if (USE_GENERIC_DUMMY_FRAMES)
1407 generic_save_call_dummy_addr (real_pc, real_pc + sizeof_dummy1);
1408 }
1409
1410 if (CALL_DUMMY_LOCATION == AFTER_TEXT_END)
1411 {
1412 extern CORE_ADDR text_end;
1413 int errcode;
1414 sp = old_sp;
1415 real_pc = text_end;
1416 errcode = target_write_memory (real_pc, (char *) dummy1, sizeof_dummy1);
1417 if (errcode != 0)
1418 error ("Cannot write text segment -- call_function failed");
1419 if (USE_GENERIC_DUMMY_FRAMES)
1420 generic_save_call_dummy_addr (real_pc, real_pc + sizeof_dummy1);
1421 }
1422
1423 if (CALL_DUMMY_LOCATION == AT_ENTRY_POINT)
1424 {
1425 real_pc = funaddr;
1426 if (USE_GENERIC_DUMMY_FRAMES)
1427 /* NOTE: cagney/2002-04-13: The entry point is going to be
1428 modified with a single breakpoint. */
1429 generic_save_call_dummy_addr (CALL_DUMMY_ADDRESS (),
1430 CALL_DUMMY_ADDRESS () + 1);
1431 }
1432
1433 #ifdef lint
1434 sp = old_sp; /* It really is used, for some ifdef's... */
1435 #endif
1436
1437 if (TYPE_CODE (ftype) == TYPE_CODE_METHOD)
1438 {
1439 i = 0;
1440 while (TYPE_CODE (TYPE_ARG_TYPES (ftype)[i]) != TYPE_CODE_VOID)
1441 i++;
1442 n_method_args = i;
1443 if (nargs < i)
1444 error ("too few arguments in method call");
1445 }
1446 else if (nargs < TYPE_NFIELDS (ftype))
1447 error ("too few arguments in function call");
1448
1449 for (i = nargs - 1; i >= 0; i--)
1450 {
1451 /* Assume that methods are always prototyped, unless they are off the
1452 end (which we should only be allowing if there is a ``...'').
1453 FIXME. */
1454 if (TYPE_CODE (ftype) == TYPE_CODE_METHOD)
1455 {
1456 if (i < n_method_args)
1457 args[i] = value_arg_coerce (args[i], TYPE_ARG_TYPES (ftype)[i], 1);
1458 else
1459 args[i] = value_arg_coerce (args[i], NULL, 0);
1460 }
1461
1462 /* If we're off the end of the known arguments, do the standard
1463 promotions. FIXME: if we had a prototype, this should only
1464 be allowed if ... were present. */
1465 if (i >= TYPE_NFIELDS (ftype))
1466 args[i] = value_arg_coerce (args[i], NULL, 0);
1467
1468 else
1469 {
1470 param_type = TYPE_FIELD_TYPE (ftype, i);
1471 args[i] = value_arg_coerce (args[i], param_type, TYPE_PROTOTYPED (ftype));
1472 }
1473
1474 /*elz: this code is to handle the case in which the function to be called
1475 has a pointer to function as parameter and the corresponding actual argument
1476 is the address of a function and not a pointer to function variable.
1477 In aCC compiled code, the calls through pointers to functions (in the body
1478 of the function called by hand) are made via $$dyncall_external which
1479 requires some registers setting, this is taken care of if we call
1480 via a function pointer variable, but not via a function address.
1481 In cc this is not a problem. */
1482
1483 if (using_gcc == 0)
1484 if (param_type)
1485 /* if this parameter is a pointer to function */
1486 if (TYPE_CODE (param_type) == TYPE_CODE_PTR)
1487 if (TYPE_CODE (param_type->target_type) == TYPE_CODE_FUNC)
1488 /* elz: FIXME here should go the test about the compiler used
1489 to compile the target. We want to issue the error
1490 message only if the compiler used was HP's aCC.
1491 If we used HP's cc, then there is no problem and no need
1492 to return at this point */
1493 if (using_gcc == 0) /* && compiler == aCC */
1494 /* go see if the actual parameter is a variable of type
1495 pointer to function or just a function */
1496 if (args[i]->lval == not_lval)
1497 {
1498 char *arg_name;
1499 if (find_pc_partial_function ((CORE_ADDR) args[i]->aligner.contents[0], &arg_name, NULL, NULL))
1500 error ("\
1501 You cannot use function <%s> as argument. \n\
1502 You must use a pointer to function type variable. Command ignored.", arg_name);
1503 }
1504 }
1505
1506 if (REG_STRUCT_HAS_ADDR_P ())
1507 {
1508 /* This is a machine like the sparc, where we may need to pass a
1509 pointer to the structure, not the structure itself. */
1510 for (i = nargs - 1; i >= 0; i--)
1511 {
1512 struct type *arg_type = check_typedef (VALUE_TYPE (args[i]));
1513 if ((TYPE_CODE (arg_type) == TYPE_CODE_STRUCT
1514 || TYPE_CODE (arg_type) == TYPE_CODE_UNION
1515 || TYPE_CODE (arg_type) == TYPE_CODE_ARRAY
1516 || TYPE_CODE (arg_type) == TYPE_CODE_STRING
1517 || TYPE_CODE (arg_type) == TYPE_CODE_BITSTRING
1518 || TYPE_CODE (arg_type) == TYPE_CODE_SET
1519 || (TYPE_CODE (arg_type) == TYPE_CODE_FLT
1520 && TYPE_LENGTH (arg_type) > 8)
1521 )
1522 && REG_STRUCT_HAS_ADDR (using_gcc, arg_type))
1523 {
1524 CORE_ADDR addr;
1525 int len; /* = TYPE_LENGTH (arg_type); */
1526 int aligned_len;
1527 arg_type = check_typedef (VALUE_ENCLOSING_TYPE (args[i]));
1528 len = TYPE_LENGTH (arg_type);
1529
1530 if (STACK_ALIGN_P ())
1531 /* MVS 11/22/96: I think at least some of this
1532 stack_align code is really broken. Better to let
1533 PUSH_ARGUMENTS adjust the stack in a target-defined
1534 manner. */
1535 aligned_len = STACK_ALIGN (len);
1536 else
1537 aligned_len = len;
1538 if (INNER_THAN (1, 2))
1539 {
1540 /* stack grows downward */
1541 sp -= aligned_len;
1542 /* ... so the address of the thing we push is the
1543 stack pointer after we push it. */
1544 addr = sp;
1545 }
1546 else
1547 {
1548 /* The stack grows up, so the address of the thing
1549 we push is the stack pointer before we push it. */
1550 addr = sp;
1551 sp += aligned_len;
1552 }
1553 /* Push the structure. */
1554 write_memory (addr, VALUE_CONTENTS_ALL (args[i]), len);
1555 /* The value we're going to pass is the address of the
1556 thing we just pushed. */
1557 /*args[i] = value_from_longest (lookup_pointer_type (value_type),
1558 (LONGEST) addr); */
1559 args[i] = value_from_pointer (lookup_pointer_type (arg_type),
1560 addr);
1561 }
1562 }
1563 }
1564
1565
1566 /* Reserve space for the return structure to be written on the
1567 stack, if necessary */
1568
1569 if (struct_return)
1570 {
1571 int len = TYPE_LENGTH (value_type);
1572 if (STACK_ALIGN_P ())
1573 /* MVS 11/22/96: I think at least some of this stack_align
1574 code is really broken. Better to let PUSH_ARGUMENTS adjust
1575 the stack in a target-defined manner. */
1576 len = STACK_ALIGN (len);
1577 if (INNER_THAN (1, 2))
1578 {
1579 /* stack grows downward */
1580 sp -= len;
1581 struct_addr = sp;
1582 }
1583 else
1584 {
1585 /* stack grows upward */
1586 struct_addr = sp;
1587 sp += len;
1588 }
1589 }
1590
1591 /* elz: on HPPA no need for this extra alignment, maybe it is needed
1592 on other architectures. This is because all the alignment is
1593 taken care of in the above code (ifdef REG_STRUCT_HAS_ADDR) and
1594 in hppa_push_arguments */
1595 if (EXTRA_STACK_ALIGNMENT_NEEDED)
1596 {
1597 /* MVS 11/22/96: I think at least some of this stack_align code
1598 is really broken. Better to let PUSH_ARGUMENTS adjust the
1599 stack in a target-defined manner. */
1600 if (STACK_ALIGN_P () && INNER_THAN (1, 2))
1601 {
1602 /* If stack grows down, we must leave a hole at the top. */
1603 int len = 0;
1604
1605 for (i = nargs - 1; i >= 0; i--)
1606 len += TYPE_LENGTH (VALUE_ENCLOSING_TYPE (args[i]));
1607 if (CALL_DUMMY_STACK_ADJUST_P)
1608 len += CALL_DUMMY_STACK_ADJUST;
1609 sp -= STACK_ALIGN (len) - len;
1610 }
1611 }
1612
1613 sp = PUSH_ARGUMENTS (nargs, args, sp, struct_return, struct_addr);
1614
1615 if (PUSH_RETURN_ADDRESS_P ())
1616 /* for targets that use no CALL_DUMMY */
1617 /* There are a number of targets now which actually don't write
1618 any CALL_DUMMY instructions into the target, but instead just
1619 save the machine state, push the arguments, and jump directly
1620 to the callee function. Since this doesn't actually involve
1621 executing a JSR/BSR instruction, the return address must be set
1622 up by hand, either by pushing onto the stack or copying into a
1623 return-address register as appropriate. Formerly this has been
1624 done in PUSH_ARGUMENTS, but that's overloading its
1625 functionality a bit, so I'm making it explicit to do it here. */
1626 sp = PUSH_RETURN_ADDRESS (real_pc, sp);
1627
1628 if (STACK_ALIGN_P () && !INNER_THAN (1, 2))
1629 {
1630 /* If stack grows up, we must leave a hole at the bottom, note
1631 that sp already has been advanced for the arguments! */
1632 if (CALL_DUMMY_STACK_ADJUST_P)
1633 sp += CALL_DUMMY_STACK_ADJUST;
1634 sp = STACK_ALIGN (sp);
1635 }
1636
1637 /* XXX This seems wrong. For stacks that grow down we shouldn't do
1638 anything here! */
1639 /* MVS 11/22/96: I think at least some of this stack_align code is
1640 really broken. Better to let PUSH_ARGUMENTS adjust the stack in
1641 a target-defined manner. */
1642 if (CALL_DUMMY_STACK_ADJUST_P)
1643 if (INNER_THAN (1, 2))
1644 {
1645 /* stack grows downward */
1646 sp -= CALL_DUMMY_STACK_ADJUST;
1647 }
1648
1649 /* Store the address at which the structure is supposed to be
1650 written. Note that this (and the code which reserved the space
1651 above) assumes that gcc was used to compile this function. Since
1652 it doesn't cost us anything but space and if the function is pcc
1653 it will ignore this value, we will make that assumption.
1654
1655 Also note that on some machines (like the sparc) pcc uses a
1656 convention like gcc's. */
1657
1658 if (struct_return)
1659 STORE_STRUCT_RETURN (struct_addr, sp);
1660
1661 /* Write the stack pointer. This is here because the statements above
1662 might fool with it. On SPARC, this write also stores the register
1663 window into the right place in the new stack frame, which otherwise
1664 wouldn't happen. (See store_inferior_registers in sparc-nat.c.) */
1665 write_sp (sp);
1666
1667 if (SAVE_DUMMY_FRAME_TOS_P ())
1668 SAVE_DUMMY_FRAME_TOS (sp);
1669
1670 {
1671 char *retbuf = (char*) alloca (REGISTER_BYTES);
1672 char *name;
1673 struct symbol *symbol;
1674
1675 name = NULL;
1676 symbol = find_pc_function (funaddr);
1677 if (symbol)
1678 {
1679 name = SYMBOL_SOURCE_NAME (symbol);
1680 }
1681 else
1682 {
1683 /* Try the minimal symbols. */
1684 struct minimal_symbol *msymbol = lookup_minimal_symbol_by_pc (funaddr);
1685
1686 if (msymbol)
1687 {
1688 name = SYMBOL_SOURCE_NAME (msymbol);
1689 }
1690 }
1691 if (name == NULL)
1692 {
1693 char format[80];
1694 sprintf (format, "at %s", local_hex_format ());
1695 name = alloca (80);
1696 /* FIXME-32x64: assumes funaddr fits in a long. */
1697 sprintf (name, format, (unsigned long) funaddr);
1698 }
1699
1700 /* Execute the stack dummy routine, calling FUNCTION.
1701 When it is done, discard the empty frame
1702 after storing the contents of all regs into retbuf. */
1703 rc = run_stack_dummy (real_pc + CALL_DUMMY_START_OFFSET, retbuf);
1704
1705 if (rc == 1)
1706 {
1707 /* We stopped inside the FUNCTION because of a random signal.
1708 Further execution of the FUNCTION is not allowed. */
1709
1710 if (unwind_on_signal_p)
1711 {
1712 /* The user wants the context restored. */
1713
1714 /* We must get back to the frame we were before the dummy call. */
1715 POP_FRAME;
1716
1717 /* FIXME: Insert a bunch of wrap_here; name can be very long if it's
1718 a C++ name with arguments and stuff. */
1719 error ("\
1720 The program being debugged was signaled while in a function called from GDB.\n\
1721 GDB has restored the context to what it was before the call.\n\
1722 To change this behavior use \"set unwindonsignal off\"\n\
1723 Evaluation of the expression containing the function (%s) will be abandoned.",
1724 name);
1725 }
1726 else
1727 {
1728 /* The user wants to stay in the frame where we stopped (default).*/
1729
1730 /* If we did the cleanups, we would print a spurious error
1731 message (Unable to restore previously selected frame),
1732 would write the registers from the inf_status (which is
1733 wrong), and would do other wrong things. */
1734 discard_cleanups (old_chain);
1735 discard_inferior_status (inf_status);
1736
1737 /* FIXME: Insert a bunch of wrap_here; name can be very long if it's
1738 a C++ name with arguments and stuff. */
1739 error ("\
1740 The program being debugged was signaled while in a function called from GDB.\n\
1741 GDB remains in the frame where the signal was received.\n\
1742 To change this behavior use \"set unwindonsignal on\"\n\
1743 Evaluation of the expression containing the function (%s) will be abandoned.",
1744 name);
1745 }
1746 }
1747
1748 if (rc == 2)
1749 {
1750 /* We hit a breakpoint inside the FUNCTION. */
1751
1752 /* If we did the cleanups, we would print a spurious error
1753 message (Unable to restore previously selected frame),
1754 would write the registers from the inf_status (which is
1755 wrong), and would do other wrong things. */
1756 discard_cleanups (old_chain);
1757 discard_inferior_status (inf_status);
1758
1759 /* The following error message used to say "The expression
1760 which contained the function call has been discarded." It
1761 is a hard concept to explain in a few words. Ideally, GDB
1762 would be able to resume evaluation of the expression when
1763 the function finally is done executing. Perhaps someday
1764 this will be implemented (it would not be easy). */
1765
1766 /* FIXME: Insert a bunch of wrap_here; name can be very long if it's
1767 a C++ name with arguments and stuff. */
1768 error ("\
1769 The program being debugged stopped while in a function called from GDB.\n\
1770 When the function (%s) is done executing, GDB will silently\n\
1771 stop (instead of continuing to evaluate the expression containing\n\
1772 the function call).", name);
1773 }
1774
1775 /* If we get here the called FUNCTION run to completion. */
1776 do_cleanups (old_chain);
1777
1778 /* Figure out the value returned by the function. */
1779 /* elz: I defined this new macro for the hppa architecture only.
1780 this gives us a way to get the value returned by the function from the stack,
1781 at the same address we told the function to put it.
1782 We cannot assume on the pa that r28 still contains the address of the returned
1783 structure. Usually this will be overwritten by the callee.
1784 I don't know about other architectures, so I defined this macro
1785 */
1786
1787 #ifdef VALUE_RETURNED_FROM_STACK
1788 if (struct_return)
1789 return (struct value *) VALUE_RETURNED_FROM_STACK (value_type, struct_addr);
1790 #endif
1791
1792 return value_being_returned (value_type, retbuf, struct_return);
1793 }
1794 }
1795
1796 struct value *
1797 call_function_by_hand (struct value *function, int nargs, struct value **args)
1798 {
1799 if (CALL_DUMMY_P)
1800 {
1801 return hand_function_call (function, nargs, args);
1802 }
1803 else
1804 {
1805 error ("Cannot invoke functions on this machine.");
1806 }
1807 }
1808 \f
1809
1810
1811 /* Create a value for an array by allocating space in the inferior, copying
1812 the data into that space, and then setting up an array value.
1813
1814 The array bounds are set from LOWBOUND and HIGHBOUND, and the array is
1815 populated from the values passed in ELEMVEC.
1816
1817 The element type of the array is inherited from the type of the
1818 first element, and all elements must have the same size (though we
1819 don't currently enforce any restriction on their types). */
1820
1821 struct value *
1822 value_array (int lowbound, int highbound, struct value **elemvec)
1823 {
1824 int nelem;
1825 int idx;
1826 unsigned int typelength;
1827 struct value *val;
1828 struct type *rangetype;
1829 struct type *arraytype;
1830 CORE_ADDR addr;
1831
1832 /* Validate that the bounds are reasonable and that each of the elements
1833 have the same size. */
1834
1835 nelem = highbound - lowbound + 1;
1836 if (nelem <= 0)
1837 {
1838 error ("bad array bounds (%d, %d)", lowbound, highbound);
1839 }
1840 typelength = TYPE_LENGTH (VALUE_ENCLOSING_TYPE (elemvec[0]));
1841 for (idx = 1; idx < nelem; idx++)
1842 {
1843 if (TYPE_LENGTH (VALUE_ENCLOSING_TYPE (elemvec[idx])) != typelength)
1844 {
1845 error ("array elements must all be the same size");
1846 }
1847 }
1848
1849 rangetype = create_range_type ((struct type *) NULL, builtin_type_int,
1850 lowbound, highbound);
1851 arraytype = create_array_type ((struct type *) NULL,
1852 VALUE_ENCLOSING_TYPE (elemvec[0]), rangetype);
1853
1854 if (!current_language->c_style_arrays)
1855 {
1856 val = allocate_value (arraytype);
1857 for (idx = 0; idx < nelem; idx++)
1858 {
1859 memcpy (VALUE_CONTENTS_ALL_RAW (val) + (idx * typelength),
1860 VALUE_CONTENTS_ALL (elemvec[idx]),
1861 typelength);
1862 }
1863 VALUE_BFD_SECTION (val) = VALUE_BFD_SECTION (elemvec[0]);
1864 return val;
1865 }
1866
1867 /* Allocate space to store the array in the inferior, and then initialize
1868 it by copying in each element. FIXME: Is it worth it to create a
1869 local buffer in which to collect each value and then write all the
1870 bytes in one operation? */
1871
1872 addr = allocate_space_in_inferior (nelem * typelength);
1873 for (idx = 0; idx < nelem; idx++)
1874 {
1875 write_memory (addr + (idx * typelength), VALUE_CONTENTS_ALL (elemvec[idx]),
1876 typelength);
1877 }
1878
1879 /* Create the array type and set up an array value to be evaluated lazily. */
1880
1881 val = value_at_lazy (arraytype, addr, VALUE_BFD_SECTION (elemvec[0]));
1882 return (val);
1883 }
1884
1885 /* Create a value for a string constant by allocating space in the inferior,
1886 copying the data into that space, and returning the address with type
1887 TYPE_CODE_STRING. PTR points to the string constant data; LEN is number
1888 of characters.
1889 Note that string types are like array of char types with a lower bound of
1890 zero and an upper bound of LEN - 1. Also note that the string may contain
1891 embedded null bytes. */
1892
1893 struct value *
1894 value_string (char *ptr, int len)
1895 {
1896 struct value *val;
1897 int lowbound = current_language->string_lower_bound;
1898 struct type *rangetype = create_range_type ((struct type *) NULL,
1899 builtin_type_int,
1900 lowbound, len + lowbound - 1);
1901 struct type *stringtype
1902 = create_string_type ((struct type *) NULL, rangetype);
1903 CORE_ADDR addr;
1904
1905 if (current_language->c_style_arrays == 0)
1906 {
1907 val = allocate_value (stringtype);
1908 memcpy (VALUE_CONTENTS_RAW (val), ptr, len);
1909 return val;
1910 }
1911
1912
1913 /* Allocate space to store the string in the inferior, and then
1914 copy LEN bytes from PTR in gdb to that address in the inferior. */
1915
1916 addr = allocate_space_in_inferior (len);
1917 write_memory (addr, ptr, len);
1918
1919 val = value_at_lazy (stringtype, addr, NULL);
1920 return (val);
1921 }
1922
1923 struct value *
1924 value_bitstring (char *ptr, int len)
1925 {
1926 struct value *val;
1927 struct type *domain_type = create_range_type (NULL, builtin_type_int,
1928 0, len - 1);
1929 struct type *type = create_set_type ((struct type *) NULL, domain_type);
1930 TYPE_CODE (type) = TYPE_CODE_BITSTRING;
1931 val = allocate_value (type);
1932 memcpy (VALUE_CONTENTS_RAW (val), ptr, TYPE_LENGTH (type));
1933 return val;
1934 }
1935 \f
1936 /* See if we can pass arguments in T2 to a function which takes arguments
1937 of types T1. Both t1 and t2 are NULL-terminated vectors. If some
1938 arguments need coercion of some sort, then the coerced values are written
1939 into T2. Return value is 0 if the arguments could be matched, or the
1940 position at which they differ if not.
1941
1942 STATICP is nonzero if the T1 argument list came from a
1943 static member function.
1944
1945 For non-static member functions, we ignore the first argument,
1946 which is the type of the instance variable. This is because we want
1947 to handle calls with objects from derived classes. This is not
1948 entirely correct: we should actually check to make sure that a
1949 requested operation is type secure, shouldn't we? FIXME. */
1950
1951 static int
1952 typecmp (int staticp, struct type *t1[], struct value *t2[])
1953 {
1954 int i;
1955
1956 if (t2 == 0)
1957 return 1;
1958 if (staticp && t1 == 0)
1959 return t2[1] != 0;
1960 if (t1 == 0)
1961 return 1;
1962 if (TYPE_CODE (t1[0]) == TYPE_CODE_VOID)
1963 return 0;
1964 if (t1[!staticp] == 0)
1965 return 0;
1966 for (i = !staticp; t1[i] && TYPE_CODE (t1[i]) != TYPE_CODE_VOID; i++)
1967 {
1968 struct type *tt1, *tt2;
1969 if (!t2[i])
1970 return i + 1;
1971 tt1 = check_typedef (t1[i]);
1972 tt2 = check_typedef (VALUE_TYPE (t2[i]));
1973 if (TYPE_CODE (tt1) == TYPE_CODE_REF
1974 /* We should be doing hairy argument matching, as below. */
1975 && (TYPE_CODE (check_typedef (TYPE_TARGET_TYPE (tt1))) == TYPE_CODE (tt2)))
1976 {
1977 if (TYPE_CODE (tt2) == TYPE_CODE_ARRAY)
1978 t2[i] = value_coerce_array (t2[i]);
1979 else
1980 t2[i] = value_addr (t2[i]);
1981 continue;
1982 }
1983
1984 /* djb - 20000715 - Until the new type structure is in the
1985 place, and we can attempt things like implicit conversions,
1986 we need to do this so you can take something like a map<const
1987 char *>, and properly access map["hello"], because the
1988 argument to [] will be a reference to a pointer to a char,
1989 and the argument will be a pointer to a char. */
1990 while ( TYPE_CODE(tt1) == TYPE_CODE_REF ||
1991 TYPE_CODE (tt1) == TYPE_CODE_PTR)
1992 {
1993 tt1 = check_typedef( TYPE_TARGET_TYPE(tt1) );
1994 }
1995 while ( TYPE_CODE(tt2) == TYPE_CODE_ARRAY ||
1996 TYPE_CODE(tt2) == TYPE_CODE_PTR ||
1997 TYPE_CODE(tt2) == TYPE_CODE_REF)
1998 {
1999 tt2 = check_typedef( TYPE_TARGET_TYPE(tt2) );
2000 }
2001 if (TYPE_CODE (tt1) == TYPE_CODE (tt2))
2002 continue;
2003 /* Array to pointer is a `trivial conversion' according to the ARM. */
2004
2005 /* We should be doing much hairier argument matching (see section 13.2
2006 of the ARM), but as a quick kludge, just check for the same type
2007 code. */
2008 if (TYPE_CODE (t1[i]) != TYPE_CODE (VALUE_TYPE (t2[i])))
2009 return i + 1;
2010 }
2011 if (!t1[i])
2012 return 0;
2013 return t2[i] ? i + 1 : 0;
2014 }
2015
2016 /* Helper function used by value_struct_elt to recurse through baseclasses.
2017 Look for a field NAME in ARG1. Adjust the address of ARG1 by OFFSET bytes,
2018 and search in it assuming it has (class) type TYPE.
2019 If found, return value, else return NULL.
2020
2021 If LOOKING_FOR_BASECLASS, then instead of looking for struct fields,
2022 look for a baseclass named NAME. */
2023
2024 static struct value *
2025 search_struct_field (char *name, struct value *arg1, int offset,
2026 register struct type *type, int looking_for_baseclass)
2027 {
2028 int i;
2029 int nbases = TYPE_N_BASECLASSES (type);
2030
2031 CHECK_TYPEDEF (type);
2032
2033 if (!looking_for_baseclass)
2034 for (i = TYPE_NFIELDS (type) - 1; i >= nbases; i--)
2035 {
2036 char *t_field_name = TYPE_FIELD_NAME (type, i);
2037
2038 if (t_field_name && (strcmp_iw (t_field_name, name) == 0))
2039 {
2040 struct value *v;
2041 if (TYPE_FIELD_STATIC (type, i))
2042 v = value_static_field (type, i);
2043 else
2044 v = value_primitive_field (arg1, offset, i, type);
2045 if (v == 0)
2046 error ("there is no field named %s", name);
2047 return v;
2048 }
2049
2050 if (t_field_name
2051 && (t_field_name[0] == '\0'
2052 || (TYPE_CODE (type) == TYPE_CODE_UNION
2053 && (strcmp_iw (t_field_name, "else") == 0))))
2054 {
2055 struct type *field_type = TYPE_FIELD_TYPE (type, i);
2056 if (TYPE_CODE (field_type) == TYPE_CODE_UNION
2057 || TYPE_CODE (field_type) == TYPE_CODE_STRUCT)
2058 {
2059 /* Look for a match through the fields of an anonymous union,
2060 or anonymous struct. C++ provides anonymous unions.
2061
2062 In the GNU Chill implementation of variant record types,
2063 each <alternative field> has an (anonymous) union type,
2064 each member of the union represents a <variant alternative>.
2065 Each <variant alternative> is represented as a struct,
2066 with a member for each <variant field>. */
2067
2068 struct value *v;
2069 int new_offset = offset;
2070
2071 /* This is pretty gross. In G++, the offset in an anonymous
2072 union is relative to the beginning of the enclosing struct.
2073 In the GNU Chill implementation of variant records,
2074 the bitpos is zero in an anonymous union field, so we
2075 have to add the offset of the union here. */
2076 if (TYPE_CODE (field_type) == TYPE_CODE_STRUCT
2077 || (TYPE_NFIELDS (field_type) > 0
2078 && TYPE_FIELD_BITPOS (field_type, 0) == 0))
2079 new_offset += TYPE_FIELD_BITPOS (type, i) / 8;
2080
2081 v = search_struct_field (name, arg1, new_offset, field_type,
2082 looking_for_baseclass);
2083 if (v)
2084 return v;
2085 }
2086 }
2087 }
2088
2089 for (i = 0; i < nbases; i++)
2090 {
2091 struct value *v;
2092 struct type *basetype = check_typedef (TYPE_BASECLASS (type, i));
2093 /* If we are looking for baseclasses, this is what we get when we
2094 hit them. But it could happen that the base part's member name
2095 is not yet filled in. */
2096 int found_baseclass = (looking_for_baseclass
2097 && TYPE_BASECLASS_NAME (type, i) != NULL
2098 && (strcmp_iw (name, TYPE_BASECLASS_NAME (type, i)) == 0));
2099
2100 if (BASETYPE_VIA_VIRTUAL (type, i))
2101 {
2102 int boffset;
2103 struct value *v2 = allocate_value (basetype);
2104
2105 boffset = baseclass_offset (type, i,
2106 VALUE_CONTENTS (arg1) + offset,
2107 VALUE_ADDRESS (arg1)
2108 + VALUE_OFFSET (arg1) + offset);
2109 if (boffset == -1)
2110 error ("virtual baseclass botch");
2111
2112 /* The virtual base class pointer might have been clobbered by the
2113 user program. Make sure that it still points to a valid memory
2114 location. */
2115
2116 boffset += offset;
2117 if (boffset < 0 || boffset >= TYPE_LENGTH (type))
2118 {
2119 CORE_ADDR base_addr;
2120
2121 base_addr = VALUE_ADDRESS (arg1) + VALUE_OFFSET (arg1) + boffset;
2122 if (target_read_memory (base_addr, VALUE_CONTENTS_RAW (v2),
2123 TYPE_LENGTH (basetype)) != 0)
2124 error ("virtual baseclass botch");
2125 VALUE_LVAL (v2) = lval_memory;
2126 VALUE_ADDRESS (v2) = base_addr;
2127 }
2128 else
2129 {
2130 VALUE_LVAL (v2) = VALUE_LVAL (arg1);
2131 VALUE_ADDRESS (v2) = VALUE_ADDRESS (arg1);
2132 VALUE_OFFSET (v2) = VALUE_OFFSET (arg1) + boffset;
2133 if (VALUE_LAZY (arg1))
2134 VALUE_LAZY (v2) = 1;
2135 else
2136 memcpy (VALUE_CONTENTS_RAW (v2),
2137 VALUE_CONTENTS_RAW (arg1) + boffset,
2138 TYPE_LENGTH (basetype));
2139 }
2140
2141 if (found_baseclass)
2142 return v2;
2143 v = search_struct_field (name, v2, 0, TYPE_BASECLASS (type, i),
2144 looking_for_baseclass);
2145 }
2146 else if (found_baseclass)
2147 v = value_primitive_field (arg1, offset, i, type);
2148 else
2149 v = search_struct_field (name, arg1,
2150 offset + TYPE_BASECLASS_BITPOS (type, i) / 8,
2151 basetype, looking_for_baseclass);
2152 if (v)
2153 return v;
2154 }
2155 return NULL;
2156 }
2157
2158
2159 /* Return the offset (in bytes) of the virtual base of type BASETYPE
2160 * in an object pointed to by VALADDR (on the host), assumed to be of
2161 * type TYPE. OFFSET is number of bytes beyond start of ARG to start
2162 * looking (in case VALADDR is the contents of an enclosing object).
2163 *
2164 * This routine recurses on the primary base of the derived class because
2165 * the virtual base entries of the primary base appear before the other
2166 * virtual base entries.
2167 *
2168 * If the virtual base is not found, a negative integer is returned.
2169 * The magnitude of the negative integer is the number of entries in
2170 * the virtual table to skip over (entries corresponding to various
2171 * ancestral classes in the chain of primary bases).
2172 *
2173 * Important: This assumes the HP / Taligent C++ runtime
2174 * conventions. Use baseclass_offset() instead to deal with g++
2175 * conventions. */
2176
2177 void
2178 find_rt_vbase_offset (struct type *type, struct type *basetype, char *valaddr,
2179 int offset, int *boffset_p, int *skip_p)
2180 {
2181 int boffset; /* offset of virtual base */
2182 int index; /* displacement to use in virtual table */
2183 int skip;
2184
2185 struct value *vp;
2186 CORE_ADDR vtbl; /* the virtual table pointer */
2187 struct type *pbc; /* the primary base class */
2188
2189 /* Look for the virtual base recursively in the primary base, first.
2190 * This is because the derived class object and its primary base
2191 * subobject share the primary virtual table. */
2192
2193 boffset = 0;
2194 pbc = TYPE_PRIMARY_BASE (type);
2195 if (pbc)
2196 {
2197 find_rt_vbase_offset (pbc, basetype, valaddr, offset, &boffset, &skip);
2198 if (skip < 0)
2199 {
2200 *boffset_p = boffset;
2201 *skip_p = -1;
2202 return;
2203 }
2204 }
2205 else
2206 skip = 0;
2207
2208
2209 /* Find the index of the virtual base according to HP/Taligent
2210 runtime spec. (Depth-first, left-to-right.) */
2211 index = virtual_base_index_skip_primaries (basetype, type);
2212
2213 if (index < 0)
2214 {
2215 *skip_p = skip + virtual_base_list_length_skip_primaries (type);
2216 *boffset_p = 0;
2217 return;
2218 }
2219
2220 /* pai: FIXME -- 32x64 possible problem */
2221 /* First word (4 bytes) in object layout is the vtable pointer */
2222 vtbl = *(CORE_ADDR *) (valaddr + offset);
2223
2224 /* Before the constructor is invoked, things are usually zero'd out. */
2225 if (vtbl == 0)
2226 error ("Couldn't find virtual table -- object may not be constructed yet.");
2227
2228
2229 /* Find virtual base's offset -- jump over entries for primary base
2230 * ancestors, then use the index computed above. But also adjust by
2231 * HP_ACC_VBASE_START for the vtable slots before the start of the
2232 * virtual base entries. Offset is negative -- virtual base entries
2233 * appear _before_ the address point of the virtual table. */
2234
2235 /* pai: FIXME -- 32x64 problem, if word = 8 bytes, change multiplier
2236 & use long type */
2237
2238 /* epstein : FIXME -- added param for overlay section. May not be correct */
2239 vp = value_at (builtin_type_int, vtbl + 4 * (-skip - index - HP_ACC_VBASE_START), NULL);
2240 boffset = value_as_long (vp);
2241 *skip_p = -1;
2242 *boffset_p = boffset;
2243 return;
2244 }
2245
2246
2247 /* Helper function used by value_struct_elt to recurse through baseclasses.
2248 Look for a field NAME in ARG1. Adjust the address of ARG1 by OFFSET bytes,
2249 and search in it assuming it has (class) type TYPE.
2250 If found, return value, else if name matched and args not return (value)-1,
2251 else return NULL. */
2252
2253 static struct value *
2254 search_struct_method (char *name, struct value **arg1p,
2255 struct value **args, int offset,
2256 int *static_memfuncp, register struct type *type)
2257 {
2258 int i;
2259 struct value *v;
2260 int name_matched = 0;
2261 char dem_opname[64];
2262
2263 CHECK_TYPEDEF (type);
2264 for (i = TYPE_NFN_FIELDS (type) - 1; i >= 0; i--)
2265 {
2266 char *t_field_name = TYPE_FN_FIELDLIST_NAME (type, i);
2267 /* FIXME! May need to check for ARM demangling here */
2268 if (strncmp (t_field_name, "__", 2) == 0 ||
2269 strncmp (t_field_name, "op", 2) == 0 ||
2270 strncmp (t_field_name, "type", 4) == 0)
2271 {
2272 if (cplus_demangle_opname (t_field_name, dem_opname, DMGL_ANSI))
2273 t_field_name = dem_opname;
2274 else if (cplus_demangle_opname (t_field_name, dem_opname, 0))
2275 t_field_name = dem_opname;
2276 }
2277 if (t_field_name && (strcmp_iw (t_field_name, name) == 0))
2278 {
2279 int j = TYPE_FN_FIELDLIST_LENGTH (type, i) - 1;
2280 struct fn_field *f = TYPE_FN_FIELDLIST1 (type, i);
2281 name_matched = 1;
2282
2283 if (j > 0 && args == 0)
2284 error ("cannot resolve overloaded method `%s': no arguments supplied", name);
2285 else if (j == 0 && args == 0)
2286 {
2287 if (TYPE_FN_FIELD_STUB (f, j))
2288 check_stub_method (type, i, j);
2289 v = value_fn_field (arg1p, f, j, type, offset);
2290 if (v != NULL)
2291 return v;
2292 }
2293 else
2294 while (j >= 0)
2295 {
2296 if (TYPE_FN_FIELD_STUB (f, j))
2297 check_stub_method (type, i, j);
2298 if (!typecmp (TYPE_FN_FIELD_STATIC_P (f, j),
2299 TYPE_FN_FIELD_ARGS (f, j), args))
2300 {
2301 if (TYPE_FN_FIELD_VIRTUAL_P (f, j))
2302 return value_virtual_fn_field (arg1p, f, j, type, offset);
2303 if (TYPE_FN_FIELD_STATIC_P (f, j) && static_memfuncp)
2304 *static_memfuncp = 1;
2305 v = value_fn_field (arg1p, f, j, type, offset);
2306 if (v != NULL)
2307 return v;
2308 }
2309 j--;
2310 }
2311 }
2312 }
2313
2314 for (i = TYPE_N_BASECLASSES (type) - 1; i >= 0; i--)
2315 {
2316 int base_offset;
2317
2318 if (BASETYPE_VIA_VIRTUAL (type, i))
2319 {
2320 if (TYPE_HAS_VTABLE (type))
2321 {
2322 /* HP aCC compiled type, search for virtual base offset
2323 according to HP/Taligent runtime spec. */
2324 int skip;
2325 find_rt_vbase_offset (type, TYPE_BASECLASS (type, i),
2326 VALUE_CONTENTS_ALL (*arg1p),
2327 offset + VALUE_EMBEDDED_OFFSET (*arg1p),
2328 &base_offset, &skip);
2329 if (skip >= 0)
2330 error ("Virtual base class offset not found in vtable");
2331 }
2332 else
2333 {
2334 struct type *baseclass = check_typedef (TYPE_BASECLASS (type, i));
2335 char *base_valaddr;
2336
2337 /* The virtual base class pointer might have been clobbered by the
2338 user program. Make sure that it still points to a valid memory
2339 location. */
2340
2341 if (offset < 0 || offset >= TYPE_LENGTH (type))
2342 {
2343 base_valaddr = (char *) alloca (TYPE_LENGTH (baseclass));
2344 if (target_read_memory (VALUE_ADDRESS (*arg1p)
2345 + VALUE_OFFSET (*arg1p) + offset,
2346 base_valaddr,
2347 TYPE_LENGTH (baseclass)) != 0)
2348 error ("virtual baseclass botch");
2349 }
2350 else
2351 base_valaddr = VALUE_CONTENTS (*arg1p) + offset;
2352
2353 base_offset =
2354 baseclass_offset (type, i, base_valaddr,
2355 VALUE_ADDRESS (*arg1p)
2356 + VALUE_OFFSET (*arg1p) + offset);
2357 if (base_offset == -1)
2358 error ("virtual baseclass botch");
2359 }
2360 }
2361 else
2362 {
2363 base_offset = TYPE_BASECLASS_BITPOS (type, i) / 8;
2364 }
2365 v = search_struct_method (name, arg1p, args, base_offset + offset,
2366 static_memfuncp, TYPE_BASECLASS (type, i));
2367 if (v == (struct value *) - 1)
2368 {
2369 name_matched = 1;
2370 }
2371 else if (v)
2372 {
2373 /* FIXME-bothner: Why is this commented out? Why is it here? */
2374 /* *arg1p = arg1_tmp; */
2375 return v;
2376 }
2377 }
2378 if (name_matched)
2379 return (struct value *) - 1;
2380 else
2381 return NULL;
2382 }
2383
2384 /* Given *ARGP, a value of type (pointer to a)* structure/union,
2385 extract the component named NAME from the ultimate target structure/union
2386 and return it as a value with its appropriate type.
2387 ERR is used in the error message if *ARGP's type is wrong.
2388
2389 C++: ARGS is a list of argument types to aid in the selection of
2390 an appropriate method. Also, handle derived types.
2391
2392 STATIC_MEMFUNCP, if non-NULL, points to a caller-supplied location
2393 where the truthvalue of whether the function that was resolved was
2394 a static member function or not is stored.
2395
2396 ERR is an error message to be printed in case the field is not found. */
2397
2398 struct value *
2399 value_struct_elt (struct value **argp, struct value **args,
2400 char *name, int *static_memfuncp, char *err)
2401 {
2402 register struct type *t;
2403 struct value *v;
2404
2405 COERCE_ARRAY (*argp);
2406
2407 t = check_typedef (VALUE_TYPE (*argp));
2408
2409 /* Follow pointers until we get to a non-pointer. */
2410
2411 while (TYPE_CODE (t) == TYPE_CODE_PTR || TYPE_CODE (t) == TYPE_CODE_REF)
2412 {
2413 *argp = value_ind (*argp);
2414 /* Don't coerce fn pointer to fn and then back again! */
2415 if (TYPE_CODE (VALUE_TYPE (*argp)) != TYPE_CODE_FUNC)
2416 COERCE_ARRAY (*argp);
2417 t = check_typedef (VALUE_TYPE (*argp));
2418 }
2419
2420 if (TYPE_CODE (t) == TYPE_CODE_MEMBER)
2421 error ("not implemented: member type in value_struct_elt");
2422
2423 if (TYPE_CODE (t) != TYPE_CODE_STRUCT
2424 && TYPE_CODE (t) != TYPE_CODE_UNION)
2425 error ("Attempt to extract a component of a value that is not a %s.", err);
2426
2427 /* Assume it's not, unless we see that it is. */
2428 if (static_memfuncp)
2429 *static_memfuncp = 0;
2430
2431 if (!args)
2432 {
2433 /* if there are no arguments ...do this... */
2434
2435 /* Try as a field first, because if we succeed, there
2436 is less work to be done. */
2437 v = search_struct_field (name, *argp, 0, t, 0);
2438 if (v)
2439 return v;
2440
2441 /* C++: If it was not found as a data field, then try to
2442 return it as a pointer to a method. */
2443
2444 if (destructor_name_p (name, t))
2445 error ("Cannot get value of destructor");
2446
2447 v = search_struct_method (name, argp, args, 0, static_memfuncp, t);
2448
2449 if (v == (struct value *) - 1)
2450 error ("Cannot take address of a method");
2451 else if (v == 0)
2452 {
2453 if (TYPE_NFN_FIELDS (t))
2454 error ("There is no member or method named %s.", name);
2455 else
2456 error ("There is no member named %s.", name);
2457 }
2458 return v;
2459 }
2460
2461 if (destructor_name_p (name, t))
2462 {
2463 if (!args[1])
2464 {
2465 /* Destructors are a special case. */
2466 int m_index, f_index;
2467
2468 v = NULL;
2469 if (get_destructor_fn_field (t, &m_index, &f_index))
2470 {
2471 v = value_fn_field (NULL, TYPE_FN_FIELDLIST1 (t, m_index),
2472 f_index, NULL, 0);
2473 }
2474 if (v == NULL)
2475 error ("could not find destructor function named %s.", name);
2476 else
2477 return v;
2478 }
2479 else
2480 {
2481 error ("destructor should not have any argument");
2482 }
2483 }
2484 else
2485 v = search_struct_method (name, argp, args, 0, static_memfuncp, t);
2486
2487 if (v == (struct value *) - 1)
2488 {
2489 error ("One of the arguments you tried to pass to %s could not be converted to what the function wants.", name);
2490 }
2491 else if (v == 0)
2492 {
2493 /* See if user tried to invoke data as function. If so,
2494 hand it back. If it's not callable (i.e., a pointer to function),
2495 gdb should give an error. */
2496 v = search_struct_field (name, *argp, 0, t, 0);
2497 }
2498
2499 if (!v)
2500 error ("Structure has no component named %s.", name);
2501 return v;
2502 }
2503
2504 /* Search through the methods of an object (and its bases)
2505 * to find a specified method. Return the pointer to the
2506 * fn_field list of overloaded instances.
2507 * Helper function for value_find_oload_list.
2508 * ARGP is a pointer to a pointer to a value (the object)
2509 * METHOD is a string containing the method name
2510 * OFFSET is the offset within the value
2511 * STATIC_MEMFUNCP is set if the method is static
2512 * TYPE is the assumed type of the object
2513 * NUM_FNS is the number of overloaded instances
2514 * BASETYPE is set to the actual type of the subobject where the method is found
2515 * BOFFSET is the offset of the base subobject where the method is found */
2516
2517 static struct fn_field *
2518 find_method_list (struct value **argp, char *method, int offset,
2519 int *static_memfuncp, struct type *type, int *num_fns,
2520 struct type **basetype, int *boffset)
2521 {
2522 int i;
2523 struct fn_field *f;
2524 CHECK_TYPEDEF (type);
2525
2526 *num_fns = 0;
2527
2528 /* First check in object itself */
2529 for (i = TYPE_NFN_FIELDS (type) - 1; i >= 0; i--)
2530 {
2531 /* pai: FIXME What about operators and type conversions? */
2532 char *fn_field_name = TYPE_FN_FIELDLIST_NAME (type, i);
2533 if (fn_field_name && (strcmp_iw (fn_field_name, method) == 0))
2534 {
2535 *num_fns = TYPE_FN_FIELDLIST_LENGTH (type, i);
2536 *basetype = type;
2537 *boffset = offset;
2538 return TYPE_FN_FIELDLIST1 (type, i);
2539 }
2540 }
2541
2542 /* Not found in object, check in base subobjects */
2543 for (i = TYPE_N_BASECLASSES (type) - 1; i >= 0; i--)
2544 {
2545 int base_offset;
2546 if (BASETYPE_VIA_VIRTUAL (type, i))
2547 {
2548 if (TYPE_HAS_VTABLE (type))
2549 {
2550 /* HP aCC compiled type, search for virtual base offset
2551 * according to HP/Taligent runtime spec. */
2552 int skip;
2553 find_rt_vbase_offset (type, TYPE_BASECLASS (type, i),
2554 VALUE_CONTENTS_ALL (*argp),
2555 offset + VALUE_EMBEDDED_OFFSET (*argp),
2556 &base_offset, &skip);
2557 if (skip >= 0)
2558 error ("Virtual base class offset not found in vtable");
2559 }
2560 else
2561 {
2562 /* probably g++ runtime model */
2563 base_offset = VALUE_OFFSET (*argp) + offset;
2564 base_offset =
2565 baseclass_offset (type, i,
2566 VALUE_CONTENTS (*argp) + base_offset,
2567 VALUE_ADDRESS (*argp) + base_offset);
2568 if (base_offset == -1)
2569 error ("virtual baseclass botch");
2570 }
2571 }
2572 else
2573 /* non-virtual base, simply use bit position from debug info */
2574 {
2575 base_offset = TYPE_BASECLASS_BITPOS (type, i) / 8;
2576 }
2577 f = find_method_list (argp, method, base_offset + offset,
2578 static_memfuncp, TYPE_BASECLASS (type, i), num_fns, basetype, boffset);
2579 if (f)
2580 return f;
2581 }
2582 return NULL;
2583 }
2584
2585 /* Return the list of overloaded methods of a specified name.
2586 * ARGP is a pointer to a pointer to a value (the object)
2587 * METHOD is the method name
2588 * OFFSET is the offset within the value contents
2589 * STATIC_MEMFUNCP is set if the method is static
2590 * NUM_FNS is the number of overloaded instances
2591 * BASETYPE is set to the type of the base subobject that defines the method
2592 * BOFFSET is the offset of the base subobject which defines the method */
2593
2594 struct fn_field *
2595 value_find_oload_method_list (struct value **argp, char *method, int offset,
2596 int *static_memfuncp, int *num_fns,
2597 struct type **basetype, int *boffset)
2598 {
2599 struct type *t;
2600
2601 t = check_typedef (VALUE_TYPE (*argp));
2602
2603 /* code snarfed from value_struct_elt */
2604 while (TYPE_CODE (t) == TYPE_CODE_PTR || TYPE_CODE (t) == TYPE_CODE_REF)
2605 {
2606 *argp = value_ind (*argp);
2607 /* Don't coerce fn pointer to fn and then back again! */
2608 if (TYPE_CODE (VALUE_TYPE (*argp)) != TYPE_CODE_FUNC)
2609 COERCE_ARRAY (*argp);
2610 t = check_typedef (VALUE_TYPE (*argp));
2611 }
2612
2613 if (TYPE_CODE (t) == TYPE_CODE_MEMBER)
2614 error ("Not implemented: member type in value_find_oload_lis");
2615
2616 if (TYPE_CODE (t) != TYPE_CODE_STRUCT
2617 && TYPE_CODE (t) != TYPE_CODE_UNION)
2618 error ("Attempt to extract a component of a value that is not a struct or union");
2619
2620 /* Assume it's not static, unless we see that it is. */
2621 if (static_memfuncp)
2622 *static_memfuncp = 0;
2623
2624 return find_method_list (argp, method, 0, static_memfuncp, t, num_fns, basetype, boffset);
2625
2626 }
2627
2628 /* Given an array of argument types (ARGTYPES) (which includes an
2629 entry for "this" in the case of C++ methods), the number of
2630 arguments NARGS, the NAME of a function whether it's a method or
2631 not (METHOD), and the degree of laxness (LAX) in conforming to
2632 overload resolution rules in ANSI C++, find the best function that
2633 matches on the argument types according to the overload resolution
2634 rules.
2635
2636 In the case of class methods, the parameter OBJ is an object value
2637 in which to search for overloaded methods.
2638
2639 In the case of non-method functions, the parameter FSYM is a symbol
2640 corresponding to one of the overloaded functions.
2641
2642 Return value is an integer: 0 -> good match, 10 -> debugger applied
2643 non-standard coercions, 100 -> incompatible.
2644
2645 If a method is being searched for, VALP will hold the value.
2646 If a non-method is being searched for, SYMP will hold the symbol for it.
2647
2648 If a method is being searched for, and it is a static method,
2649 then STATICP will point to a non-zero value.
2650
2651 Note: This function does *not* check the value of
2652 overload_resolution. Caller must check it to see whether overload
2653 resolution is permitted.
2654 */
2655
2656 int
2657 find_overload_match (struct type **arg_types, int nargs, char *name, int method,
2658 int lax, struct value **objp, struct symbol *fsym,
2659 struct value **valp, struct symbol **symp, int *staticp)
2660 {
2661 int nparms;
2662 struct type **parm_types;
2663 int champ_nparms = 0;
2664 struct value *obj = (objp ? *objp : NULL);
2665
2666 short oload_champ = -1; /* Index of best overloaded function */
2667 short oload_ambiguous = 0; /* Current ambiguity state for overload resolution */
2668 /* 0 => no ambiguity, 1 => two good funcs, 2 => incomparable funcs */
2669 short oload_ambig_champ = -1; /* 2nd contender for best match */
2670 short oload_non_standard = 0; /* did we have to use non-standard conversions? */
2671 short oload_incompatible = 0; /* are args supplied incompatible with any function? */
2672
2673 struct badness_vector *bv; /* A measure of how good an overloaded instance is */
2674 struct badness_vector *oload_champ_bv = NULL; /* The measure for the current best match */
2675
2676 struct value *temp = obj;
2677 struct fn_field *fns_ptr = NULL; /* For methods, the list of overloaded methods */
2678 struct symbol **oload_syms = NULL; /* For non-methods, the list of overloaded function symbols */
2679 int num_fns = 0; /* Number of overloaded instances being considered */
2680 struct type *basetype = NULL;
2681 int boffset;
2682 register int jj;
2683 register int ix;
2684
2685 char *obj_type_name = NULL;
2686 char *func_name = NULL;
2687
2688 /* Get the list of overloaded methods or functions */
2689 if (method)
2690 {
2691 int i;
2692 int len;
2693 struct type *domain;
2694 obj_type_name = TYPE_NAME (VALUE_TYPE (obj));
2695 /* Hack: evaluate_subexp_standard often passes in a pointer
2696 value rather than the object itself, so try again */
2697 if ((!obj_type_name || !*obj_type_name) &&
2698 (TYPE_CODE (VALUE_TYPE (obj)) == TYPE_CODE_PTR))
2699 obj_type_name = TYPE_NAME (TYPE_TARGET_TYPE (VALUE_TYPE (obj)));
2700
2701 fns_ptr = value_find_oload_method_list (&temp, name, 0,
2702 staticp,
2703 &num_fns,
2704 &basetype, &boffset);
2705 if (!fns_ptr || !num_fns)
2706 error ("Couldn't find method %s%s%s",
2707 obj_type_name,
2708 (obj_type_name && *obj_type_name) ? "::" : "",
2709 name);
2710 domain = TYPE_DOMAIN_TYPE (fns_ptr[0].type);
2711 len = TYPE_NFN_FIELDS (domain);
2712 /* NOTE: dan/2000-03-10: This stuff is for STABS, which won't
2713 give us the info we need directly in the types. We have to
2714 use the method stub conversion to get it. Be aware that this
2715 is by no means perfect, and if you use STABS, please move to
2716 DWARF-2, or something like it, because trying to improve
2717 overloading using STABS is really a waste of time. */
2718 for (i = 0; i < len; i++)
2719 {
2720 int j;
2721 struct fn_field *f = TYPE_FN_FIELDLIST1 (domain, i);
2722 int len2 = TYPE_FN_FIELDLIST_LENGTH (domain, i);
2723
2724 for (j = 0; j < len2; j++)
2725 {
2726 if (TYPE_FN_FIELD_STUB (f, j) && (!strcmp_iw (TYPE_FN_FIELDLIST_NAME (domain,i),name)))
2727 check_stub_method (domain, i, j);
2728 }
2729 }
2730 }
2731 else
2732 {
2733 int i = -1;
2734 func_name = cplus_demangle (SYMBOL_NAME (fsym), DMGL_NO_OPTS);
2735
2736 /* If the name is NULL this must be a C-style function.
2737 Just return the same symbol. */
2738 if (!func_name)
2739 {
2740 *symp = fsym;
2741 return 0;
2742 }
2743
2744 oload_syms = make_symbol_overload_list (fsym);
2745 while (oload_syms[++i])
2746 num_fns++;
2747 if (!num_fns)
2748 error ("Couldn't find function %s", func_name);
2749 }
2750
2751 oload_champ_bv = NULL;
2752
2753 /* Consider each candidate in turn */
2754 for (ix = 0; ix < num_fns; ix++)
2755 {
2756 if (method)
2757 {
2758 /* For static member functions, we won't have a this pointer, but nothing
2759 else seems to handle them right now, so we just pretend ourselves */
2760 nparms=0;
2761
2762 if (TYPE_FN_FIELD_ARGS(fns_ptr,ix))
2763 {
2764 while (TYPE_CODE(TYPE_FN_FIELD_ARGS(fns_ptr,ix)[nparms]) != TYPE_CODE_VOID)
2765 nparms++;
2766 }
2767 }
2768 else
2769 {
2770 /* If it's not a method, this is the proper place */
2771 nparms=TYPE_NFIELDS(SYMBOL_TYPE(oload_syms[ix]));
2772 }
2773
2774 /* Prepare array of parameter types */
2775 parm_types = (struct type **) xmalloc (nparms * (sizeof (struct type *)));
2776 for (jj = 0; jj < nparms; jj++)
2777 parm_types[jj] = (method
2778 ? (TYPE_FN_FIELD_ARGS (fns_ptr, ix)[jj])
2779 : TYPE_FIELD_TYPE (SYMBOL_TYPE (oload_syms[ix]), jj));
2780
2781 /* Compare parameter types to supplied argument types */
2782 bv = rank_function (parm_types, nparms, arg_types, nargs);
2783
2784 if (!oload_champ_bv)
2785 {
2786 oload_champ_bv = bv;
2787 oload_champ = 0;
2788 champ_nparms = nparms;
2789 }
2790 else
2791 /* See whether current candidate is better or worse than previous best */
2792 switch (compare_badness (bv, oload_champ_bv))
2793 {
2794 case 0:
2795 oload_ambiguous = 1; /* top two contenders are equally good */
2796 oload_ambig_champ = ix;
2797 break;
2798 case 1:
2799 oload_ambiguous = 2; /* incomparable top contenders */
2800 oload_ambig_champ = ix;
2801 break;
2802 case 2:
2803 oload_champ_bv = bv; /* new champion, record details */
2804 oload_ambiguous = 0;
2805 oload_champ = ix;
2806 oload_ambig_champ = -1;
2807 champ_nparms = nparms;
2808 break;
2809 case 3:
2810 default:
2811 break;
2812 }
2813 xfree (parm_types);
2814 if (overload_debug)
2815 {
2816 if (method)
2817 fprintf_filtered (gdb_stderr,"Overloaded method instance %s, # of parms %d\n", fns_ptr[ix].physname, nparms);
2818 else
2819 fprintf_filtered (gdb_stderr,"Overloaded function instance %s # of parms %d\n", SYMBOL_DEMANGLED_NAME (oload_syms[ix]), nparms);
2820 for (jj = 0; jj < nargs; jj++)
2821 fprintf_filtered (gdb_stderr,"...Badness @ %d : %d\n", jj, bv->rank[jj]);
2822 fprintf_filtered (gdb_stderr,"Overload resolution champion is %d, ambiguous? %d\n", oload_champ, oload_ambiguous);
2823 }
2824 } /* end loop over all candidates */
2825 /* NOTE: dan/2000-03-10: Seems to be a better idea to just pick one
2826 if they have the exact same goodness. This is because there is no
2827 way to differentiate based on return type, which we need to in
2828 cases like overloads of .begin() <It's both const and non-const> */
2829 #if 0
2830 if (oload_ambiguous)
2831 {
2832 if (method)
2833 error ("Cannot resolve overloaded method %s%s%s to unique instance; disambiguate by specifying function signature",
2834 obj_type_name,
2835 (obj_type_name && *obj_type_name) ? "::" : "",
2836 name);
2837 else
2838 error ("Cannot resolve overloaded function %s to unique instance; disambiguate by specifying function signature",
2839 func_name);
2840 }
2841 #endif
2842
2843 /* Check how bad the best match is */
2844 for (ix = 1; ix <= nargs; ix++)
2845 {
2846 if (oload_champ_bv->rank[ix] >= 100)
2847 oload_incompatible = 1; /* truly mismatched types */
2848
2849 else if (oload_champ_bv->rank[ix] >= 10)
2850 oload_non_standard = 1; /* non-standard type conversions needed */
2851 }
2852 if (oload_incompatible)
2853 {
2854 if (method)
2855 error ("Cannot resolve method %s%s%s to any overloaded instance",
2856 obj_type_name,
2857 (obj_type_name && *obj_type_name) ? "::" : "",
2858 name);
2859 else
2860 error ("Cannot resolve function %s to any overloaded instance",
2861 func_name);
2862 }
2863 else if (oload_non_standard)
2864 {
2865 if (method)
2866 warning ("Using non-standard conversion to match method %s%s%s to supplied arguments",
2867 obj_type_name,
2868 (obj_type_name && *obj_type_name) ? "::" : "",
2869 name);
2870 else
2871 warning ("Using non-standard conversion to match function %s to supplied arguments",
2872 func_name);
2873 }
2874
2875 if (method)
2876 {
2877 if (TYPE_FN_FIELD_VIRTUAL_P (fns_ptr, oload_champ))
2878 *valp = value_virtual_fn_field (&temp, fns_ptr, oload_champ, basetype, boffset);
2879 else
2880 *valp = value_fn_field (&temp, fns_ptr, oload_champ, basetype, boffset);
2881 }
2882 else
2883 {
2884 *symp = oload_syms[oload_champ];
2885 xfree (func_name);
2886 }
2887
2888 if (objp)
2889 {
2890 if (TYPE_CODE (VALUE_TYPE (temp)) != TYPE_CODE_PTR
2891 && TYPE_CODE (VALUE_TYPE (*objp)) == TYPE_CODE_PTR)
2892 {
2893 temp = value_addr (temp);
2894 }
2895 *objp = temp;
2896 }
2897 return oload_incompatible ? 100 : (oload_non_standard ? 10 : 0);
2898 }
2899
2900 /* C++: return 1 is NAME is a legitimate name for the destructor
2901 of type TYPE. If TYPE does not have a destructor, or
2902 if NAME is inappropriate for TYPE, an error is signaled. */
2903 int
2904 destructor_name_p (const char *name, const struct type *type)
2905 {
2906 /* destructors are a special case. */
2907
2908 if (name[0] == '~')
2909 {
2910 char *dname = type_name_no_tag (type);
2911 char *cp = strchr (dname, '<');
2912 unsigned int len;
2913
2914 /* Do not compare the template part for template classes. */
2915 if (cp == NULL)
2916 len = strlen (dname);
2917 else
2918 len = cp - dname;
2919 if (strlen (name + 1) != len || !STREQN (dname, name + 1, len))
2920 error ("name of destructor must equal name of class");
2921 else
2922 return 1;
2923 }
2924 return 0;
2925 }
2926
2927 /* Helper function for check_field: Given TYPE, a structure/union,
2928 return 1 if the component named NAME from the ultimate
2929 target structure/union is defined, otherwise, return 0. */
2930
2931 static int
2932 check_field_in (register struct type *type, const char *name)
2933 {
2934 register int i;
2935
2936 for (i = TYPE_NFIELDS (type) - 1; i >= TYPE_N_BASECLASSES (type); i--)
2937 {
2938 char *t_field_name = TYPE_FIELD_NAME (type, i);
2939 if (t_field_name && (strcmp_iw (t_field_name, name) == 0))
2940 return 1;
2941 }
2942
2943 /* C++: If it was not found as a data field, then try to
2944 return it as a pointer to a method. */
2945
2946 /* Destructors are a special case. */
2947 if (destructor_name_p (name, type))
2948 {
2949 int m_index, f_index;
2950
2951 return get_destructor_fn_field (type, &m_index, &f_index);
2952 }
2953
2954 for (i = TYPE_NFN_FIELDS (type) - 1; i >= 0; --i)
2955 {
2956 if (strcmp_iw (TYPE_FN_FIELDLIST_NAME (type, i), name) == 0)
2957 return 1;
2958 }
2959
2960 for (i = TYPE_N_BASECLASSES (type) - 1; i >= 0; i--)
2961 if (check_field_in (TYPE_BASECLASS (type, i), name))
2962 return 1;
2963
2964 return 0;
2965 }
2966
2967
2968 /* C++: Given ARG1, a value of type (pointer to a)* structure/union,
2969 return 1 if the component named NAME from the ultimate
2970 target structure/union is defined, otherwise, return 0. */
2971
2972 int
2973 check_field (struct value *arg1, const char *name)
2974 {
2975 register struct type *t;
2976
2977 COERCE_ARRAY (arg1);
2978
2979 t = VALUE_TYPE (arg1);
2980
2981 /* Follow pointers until we get to a non-pointer. */
2982
2983 for (;;)
2984 {
2985 CHECK_TYPEDEF (t);
2986 if (TYPE_CODE (t) != TYPE_CODE_PTR && TYPE_CODE (t) != TYPE_CODE_REF)
2987 break;
2988 t = TYPE_TARGET_TYPE (t);
2989 }
2990
2991 if (TYPE_CODE (t) == TYPE_CODE_MEMBER)
2992 error ("not implemented: member type in check_field");
2993
2994 if (TYPE_CODE (t) != TYPE_CODE_STRUCT
2995 && TYPE_CODE (t) != TYPE_CODE_UNION)
2996 error ("Internal error: `this' is not an aggregate");
2997
2998 return check_field_in (t, name);
2999 }
3000
3001 /* C++: Given an aggregate type CURTYPE, and a member name NAME,
3002 return the address of this member as a "pointer to member"
3003 type. If INTYPE is non-null, then it will be the type
3004 of the member we are looking for. This will help us resolve
3005 "pointers to member functions". This function is used
3006 to resolve user expressions of the form "DOMAIN::NAME". */
3007
3008 struct value *
3009 value_struct_elt_for_reference (struct type *domain, int offset,
3010 struct type *curtype, char *name,
3011 struct type *intype)
3012 {
3013 register struct type *t = curtype;
3014 register int i;
3015 struct value *v;
3016
3017 if (TYPE_CODE (t) != TYPE_CODE_STRUCT
3018 && TYPE_CODE (t) != TYPE_CODE_UNION)
3019 error ("Internal error: non-aggregate type to value_struct_elt_for_reference");
3020
3021 for (i = TYPE_NFIELDS (t) - 1; i >= TYPE_N_BASECLASSES (t); i--)
3022 {
3023 char *t_field_name = TYPE_FIELD_NAME (t, i);
3024
3025 if (t_field_name && STREQ (t_field_name, name))
3026 {
3027 if (TYPE_FIELD_STATIC (t, i))
3028 {
3029 v = value_static_field (t, i);
3030 if (v == NULL)
3031 error ("Internal error: could not find static variable %s",
3032 name);
3033 return v;
3034 }
3035 if (TYPE_FIELD_PACKED (t, i))
3036 error ("pointers to bitfield members not allowed");
3037
3038 return value_from_longest
3039 (lookup_reference_type (lookup_member_type (TYPE_FIELD_TYPE (t, i),
3040 domain)),
3041 offset + (LONGEST) (TYPE_FIELD_BITPOS (t, i) >> 3));
3042 }
3043 }
3044
3045 /* C++: If it was not found as a data field, then try to
3046 return it as a pointer to a method. */
3047
3048 /* Destructors are a special case. */
3049 if (destructor_name_p (name, t))
3050 {
3051 error ("member pointers to destructors not implemented yet");
3052 }
3053
3054 /* Perform all necessary dereferencing. */
3055 while (intype && TYPE_CODE (intype) == TYPE_CODE_PTR)
3056 intype = TYPE_TARGET_TYPE (intype);
3057
3058 for (i = TYPE_NFN_FIELDS (t) - 1; i >= 0; --i)
3059 {
3060 char *t_field_name = TYPE_FN_FIELDLIST_NAME (t, i);
3061 char dem_opname[64];
3062
3063 if (strncmp (t_field_name, "__", 2) == 0 ||
3064 strncmp (t_field_name, "op", 2) == 0 ||
3065 strncmp (t_field_name, "type", 4) == 0)
3066 {
3067 if (cplus_demangle_opname (t_field_name, dem_opname, DMGL_ANSI))
3068 t_field_name = dem_opname;
3069 else if (cplus_demangle_opname (t_field_name, dem_opname, 0))
3070 t_field_name = dem_opname;
3071 }
3072 if (t_field_name && STREQ (t_field_name, name))
3073 {
3074 int j = TYPE_FN_FIELDLIST_LENGTH (t, i);
3075 struct fn_field *f = TYPE_FN_FIELDLIST1 (t, i);
3076
3077 if (intype == 0 && j > 1)
3078 error ("non-unique member `%s' requires type instantiation", name);
3079 if (intype)
3080 {
3081 while (j--)
3082 if (TYPE_FN_FIELD_TYPE (f, j) == intype)
3083 break;
3084 if (j < 0)
3085 error ("no member function matches that type instantiation");
3086 }
3087 else
3088 j = 0;
3089
3090 if (TYPE_FN_FIELD_STUB (f, j))
3091 check_stub_method (t, i, j);
3092 if (TYPE_FN_FIELD_VIRTUAL_P (f, j))
3093 {
3094 return value_from_longest
3095 (lookup_reference_type
3096 (lookup_member_type (TYPE_FN_FIELD_TYPE (f, j),
3097 domain)),
3098 (LONGEST) METHOD_PTR_FROM_VOFFSET (TYPE_FN_FIELD_VOFFSET (f, j)));
3099 }
3100 else
3101 {
3102 struct symbol *s = lookup_symbol (TYPE_FN_FIELD_PHYSNAME (f, j),
3103 0, VAR_NAMESPACE, 0, NULL);
3104 if (s == NULL)
3105 {
3106 v = 0;
3107 }
3108 else
3109 {
3110 v = read_var_value (s, 0);
3111 #if 0
3112 VALUE_TYPE (v) = lookup_reference_type
3113 (lookup_member_type (TYPE_FN_FIELD_TYPE (f, j),
3114 domain));
3115 #endif
3116 }
3117 return v;
3118 }
3119 }
3120 }
3121 for (i = TYPE_N_BASECLASSES (t) - 1; i >= 0; i--)
3122 {
3123 struct value *v;
3124 int base_offset;
3125
3126 if (BASETYPE_VIA_VIRTUAL (t, i))
3127 base_offset = 0;
3128 else
3129 base_offset = TYPE_BASECLASS_BITPOS (t, i) / 8;
3130 v = value_struct_elt_for_reference (domain,
3131 offset + base_offset,
3132 TYPE_BASECLASS (t, i),
3133 name,
3134 intype);
3135 if (v)
3136 return v;
3137 }
3138 return 0;
3139 }
3140
3141
3142 /* Given a pointer value V, find the real (RTTI) type
3143 of the object it points to.
3144 Other parameters FULL, TOP, USING_ENC as with value_rtti_type()
3145 and refer to the values computed for the object pointed to. */
3146
3147 struct type *
3148 value_rtti_target_type (struct value *v, int *full, int *top, int *using_enc)
3149 {
3150 struct value *target;
3151
3152 target = value_ind (v);
3153
3154 return value_rtti_type (target, full, top, using_enc);
3155 }
3156
3157 /* Given a value pointed to by ARGP, check its real run-time type, and
3158 if that is different from the enclosing type, create a new value
3159 using the real run-time type as the enclosing type (and of the same
3160 type as ARGP) and return it, with the embedded offset adjusted to
3161 be the correct offset to the enclosed object
3162 RTYPE is the type, and XFULL, XTOP, and XUSING_ENC are the other
3163 parameters, computed by value_rtti_type(). If these are available,
3164 they can be supplied and a second call to value_rtti_type() is avoided.
3165 (Pass RTYPE == NULL if they're not available */
3166
3167 struct value *
3168 value_full_object (struct value *argp, struct type *rtype, int xfull, int xtop,
3169 int xusing_enc)
3170 {
3171 struct type *real_type;
3172 int full = 0;
3173 int top = -1;
3174 int using_enc = 0;
3175 struct value *new_val;
3176
3177 if (rtype)
3178 {
3179 real_type = rtype;
3180 full = xfull;
3181 top = xtop;
3182 using_enc = xusing_enc;
3183 }
3184 else
3185 real_type = value_rtti_type (argp, &full, &top, &using_enc);
3186
3187 /* If no RTTI data, or if object is already complete, do nothing */
3188 if (!real_type || real_type == VALUE_ENCLOSING_TYPE (argp))
3189 return argp;
3190
3191 /* If we have the full object, but for some reason the enclosing
3192 type is wrong, set it *//* pai: FIXME -- sounds iffy */
3193 if (full)
3194 {
3195 argp = value_change_enclosing_type (argp, real_type);
3196 return argp;
3197 }
3198
3199 /* Check if object is in memory */
3200 if (VALUE_LVAL (argp) != lval_memory)
3201 {
3202 warning ("Couldn't retrieve complete object of RTTI type %s; object may be in register(s).", TYPE_NAME (real_type));
3203
3204 return argp;
3205 }
3206
3207 /* All other cases -- retrieve the complete object */
3208 /* Go back by the computed top_offset from the beginning of the object,
3209 adjusting for the embedded offset of argp if that's what value_rtti_type
3210 used for its computation. */
3211 new_val = value_at_lazy (real_type, VALUE_ADDRESS (argp) - top +
3212 (using_enc ? 0 : VALUE_EMBEDDED_OFFSET (argp)),
3213 VALUE_BFD_SECTION (argp));
3214 VALUE_TYPE (new_val) = VALUE_TYPE (argp);
3215 VALUE_EMBEDDED_OFFSET (new_val) = using_enc ? top + VALUE_EMBEDDED_OFFSET (argp) : top;
3216 return new_val;
3217 }
3218
3219
3220
3221
3222 /* C++: return the value of the class instance variable, if one exists.
3223 Flag COMPLAIN signals an error if the request is made in an
3224 inappropriate context. */
3225
3226 struct value *
3227 value_of_this (int complain)
3228 {
3229 struct symbol *func, *sym;
3230 struct block *b;
3231 int i;
3232 static const char funny_this[] = "this";
3233 struct value *this;
3234
3235 if (selected_frame == 0)
3236 {
3237 if (complain)
3238 error ("no frame selected");
3239 else
3240 return 0;
3241 }
3242
3243 func = get_frame_function (selected_frame);
3244 if (!func)
3245 {
3246 if (complain)
3247 error ("no `this' in nameless context");
3248 else
3249 return 0;
3250 }
3251
3252 b = SYMBOL_BLOCK_VALUE (func);
3253 i = BLOCK_NSYMS (b);
3254 if (i <= 0)
3255 {
3256 if (complain)
3257 error ("no args, no `this'");
3258 else
3259 return 0;
3260 }
3261
3262 /* Calling lookup_block_symbol is necessary to get the LOC_REGISTER
3263 symbol instead of the LOC_ARG one (if both exist). */
3264 sym = lookup_block_symbol (b, funny_this, NULL, VAR_NAMESPACE);
3265 if (sym == NULL)
3266 {
3267 if (complain)
3268 error ("current stack frame not in method");
3269 else
3270 return NULL;
3271 }
3272
3273 this = read_var_value (sym, selected_frame);
3274 if (this == 0 && complain)
3275 error ("`this' argument at unknown address");
3276 return this;
3277 }
3278
3279 /* Create a slice (sub-string, sub-array) of ARRAY, that is LENGTH elements
3280 long, starting at LOWBOUND. The result has the same lower bound as
3281 the original ARRAY. */
3282
3283 struct value *
3284 value_slice (struct value *array, int lowbound, int length)
3285 {
3286 struct type *slice_range_type, *slice_type, *range_type;
3287 LONGEST lowerbound, upperbound, offset;
3288 struct value *slice;
3289 struct type *array_type;
3290 array_type = check_typedef (VALUE_TYPE (array));
3291 COERCE_VARYING_ARRAY (array, array_type);
3292 if (TYPE_CODE (array_type) != TYPE_CODE_ARRAY
3293 && TYPE_CODE (array_type) != TYPE_CODE_STRING
3294 && TYPE_CODE (array_type) != TYPE_CODE_BITSTRING)
3295 error ("cannot take slice of non-array");
3296 range_type = TYPE_INDEX_TYPE (array_type);
3297 if (get_discrete_bounds (range_type, &lowerbound, &upperbound) < 0)
3298 error ("slice from bad array or bitstring");
3299 if (lowbound < lowerbound || length < 0
3300 || lowbound + length - 1 > upperbound
3301 /* Chill allows zero-length strings but not arrays. */
3302 || (current_language->la_language == language_chill
3303 && length == 0 && TYPE_CODE (array_type) == TYPE_CODE_ARRAY))
3304 error ("slice out of range");
3305 /* FIXME-type-allocation: need a way to free this type when we are
3306 done with it. */
3307 slice_range_type = create_range_type ((struct type *) NULL,
3308 TYPE_TARGET_TYPE (range_type),
3309 lowbound, lowbound + length - 1);
3310 if (TYPE_CODE (array_type) == TYPE_CODE_BITSTRING)
3311 {
3312 int i;
3313 slice_type = create_set_type ((struct type *) NULL, slice_range_type);
3314 TYPE_CODE (slice_type) = TYPE_CODE_BITSTRING;
3315 slice = value_zero (slice_type, not_lval);
3316 for (i = 0; i < length; i++)
3317 {
3318 int element = value_bit_index (array_type,
3319 VALUE_CONTENTS (array),
3320 lowbound + i);
3321 if (element < 0)
3322 error ("internal error accessing bitstring");
3323 else if (element > 0)
3324 {
3325 int j = i % TARGET_CHAR_BIT;
3326 if (BITS_BIG_ENDIAN)
3327 j = TARGET_CHAR_BIT - 1 - j;
3328 VALUE_CONTENTS_RAW (slice)[i / TARGET_CHAR_BIT] |= (1 << j);
3329 }
3330 }
3331 /* We should set the address, bitssize, and bitspos, so the clice
3332 can be used on the LHS, but that may require extensions to
3333 value_assign. For now, just leave as a non_lval. FIXME. */
3334 }
3335 else
3336 {
3337 struct type *element_type = TYPE_TARGET_TYPE (array_type);
3338 offset
3339 = (lowbound - lowerbound) * TYPE_LENGTH (check_typedef (element_type));
3340 slice_type = create_array_type ((struct type *) NULL, element_type,
3341 slice_range_type);
3342 TYPE_CODE (slice_type) = TYPE_CODE (array_type);
3343 slice = allocate_value (slice_type);
3344 if (VALUE_LAZY (array))
3345 VALUE_LAZY (slice) = 1;
3346 else
3347 memcpy (VALUE_CONTENTS (slice), VALUE_CONTENTS (array) + offset,
3348 TYPE_LENGTH (slice_type));
3349 if (VALUE_LVAL (array) == lval_internalvar)
3350 VALUE_LVAL (slice) = lval_internalvar_component;
3351 else
3352 VALUE_LVAL (slice) = VALUE_LVAL (array);
3353 VALUE_ADDRESS (slice) = VALUE_ADDRESS (array);
3354 VALUE_OFFSET (slice) = VALUE_OFFSET (array) + offset;
3355 }
3356 return slice;
3357 }
3358
3359 /* Assuming chill_varying_type (VARRAY) is true, return an equivalent
3360 value as a fixed-length array. */
3361
3362 struct value *
3363 varying_to_slice (struct value *varray)
3364 {
3365 struct type *vtype = check_typedef (VALUE_TYPE (varray));
3366 LONGEST length = unpack_long (TYPE_FIELD_TYPE (vtype, 0),
3367 VALUE_CONTENTS (varray)
3368 + TYPE_FIELD_BITPOS (vtype, 0) / 8);
3369 return value_slice (value_primitive_field (varray, 0, 1, vtype), 0, length);
3370 }
3371
3372 /* Create a value for a FORTRAN complex number. Currently most of
3373 the time values are coerced to COMPLEX*16 (i.e. a complex number
3374 composed of 2 doubles. This really should be a smarter routine
3375 that figures out precision inteligently as opposed to assuming
3376 doubles. FIXME: fmb */
3377
3378 struct value *
3379 value_literal_complex (struct value *arg1, struct value *arg2, struct type *type)
3380 {
3381 struct value *val;
3382 struct type *real_type = TYPE_TARGET_TYPE (type);
3383
3384 val = allocate_value (type);
3385 arg1 = value_cast (real_type, arg1);
3386 arg2 = value_cast (real_type, arg2);
3387
3388 memcpy (VALUE_CONTENTS_RAW (val),
3389 VALUE_CONTENTS (arg1), TYPE_LENGTH (real_type));
3390 memcpy (VALUE_CONTENTS_RAW (val) + TYPE_LENGTH (real_type),
3391 VALUE_CONTENTS (arg2), TYPE_LENGTH (real_type));
3392 return val;
3393 }
3394
3395 /* Cast a value into the appropriate complex data type. */
3396
3397 static struct value *
3398 cast_into_complex (struct type *type, struct value *val)
3399 {
3400 struct type *real_type = TYPE_TARGET_TYPE (type);
3401 if (TYPE_CODE (VALUE_TYPE (val)) == TYPE_CODE_COMPLEX)
3402 {
3403 struct type *val_real_type = TYPE_TARGET_TYPE (VALUE_TYPE (val));
3404 struct value *re_val = allocate_value (val_real_type);
3405 struct value *im_val = allocate_value (val_real_type);
3406
3407 memcpy (VALUE_CONTENTS_RAW (re_val),
3408 VALUE_CONTENTS (val), TYPE_LENGTH (val_real_type));
3409 memcpy (VALUE_CONTENTS_RAW (im_val),
3410 VALUE_CONTENTS (val) + TYPE_LENGTH (val_real_type),
3411 TYPE_LENGTH (val_real_type));
3412
3413 return value_literal_complex (re_val, im_val, type);
3414 }
3415 else if (TYPE_CODE (VALUE_TYPE (val)) == TYPE_CODE_FLT
3416 || TYPE_CODE (VALUE_TYPE (val)) == TYPE_CODE_INT)
3417 return value_literal_complex (val, value_zero (real_type, not_lval), type);
3418 else
3419 error ("cannot cast non-number to complex");
3420 }
3421
3422 void
3423 _initialize_valops (void)
3424 {
3425 #if 0
3426 add_show_from_set
3427 (add_set_cmd ("abandon", class_support, var_boolean, (char *) &auto_abandon,
3428 "Set automatic abandonment of expressions upon failure.",
3429 &setlist),
3430 &showlist);
3431 #endif
3432
3433 add_show_from_set
3434 (add_set_cmd ("overload-resolution", class_support, var_boolean, (char *) &overload_resolution,
3435 "Set overload resolution in evaluating C++ functions.",
3436 &setlist),
3437 &showlist);
3438 overload_resolution = 1;
3439
3440 add_show_from_set (
3441 add_set_cmd ("unwindonsignal", no_class, var_boolean,
3442 (char *) &unwind_on_signal_p,
3443 "Set unwinding of stack if a signal is received while in a call dummy.\n\
3444 The unwindonsignal lets the user determine what gdb should do if a signal\n\
3445 is received while in a function called from gdb (call dummy). If set, gdb\n\
3446 unwinds the stack and restore the context to what as it was before the call.\n\
3447 The default is to stop in the frame where the signal was received.", &setlist),
3448 &showlist);
3449 }
This page took 0.115378 seconds and 4 git commands to generate.