2005-05-11 Daniel Jacobowitz <drow@mvista.com>
[deliverable/binutils-gdb.git] / gdb / valops.c
1 /* Perform non-arithmetic operations on values, for GDB.
2 Copyright 1986, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994,
3 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002
4 Free Software Foundation, Inc.
5
6 This file is part of GDB.
7
8 This program is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 2 of the License, or
11 (at your option) any later version.
12
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
17
18 You should have received a copy of the GNU General Public License
19 along with this program; if not, write to the Free Software
20 Foundation, Inc., 59 Temple Place - Suite 330,
21 Boston, MA 02111-1307, USA. */
22
23 #include "defs.h"
24 #include "symtab.h"
25 #include "gdbtypes.h"
26 #include "value.h"
27 #include "frame.h"
28 #include "inferior.h"
29 #include "gdbcore.h"
30 #include "target.h"
31 #include "demangle.h"
32 #include "language.h"
33 #include "gdbcmd.h"
34 #include "regcache.h"
35 #include "cp-abi.h"
36
37 #include <errno.h>
38 #include "gdb_string.h"
39 #include "gdb_assert.h"
40
41 /* Flag indicating HP compilers were used; needed to correctly handle some
42 value operations with HP aCC code/runtime. */
43 extern int hp_som_som_object_present;
44
45 extern int overload_debug;
46 /* Local functions. */
47
48 static int typecmp (int staticp, struct type *t1[], struct value *t2[]);
49
50 static CORE_ADDR find_function_addr (struct value *, struct type **);
51 static struct value *value_arg_coerce (struct value *, struct type *, int);
52
53
54 static CORE_ADDR value_push (CORE_ADDR, struct value *);
55
56 static struct value *search_struct_field (char *, struct value *, int,
57 struct type *, int);
58
59 static struct value *search_struct_method (char *, struct value **,
60 struct value **,
61 int, int *, struct type *);
62
63 static int check_field_in (struct type *, const char *);
64
65 static CORE_ADDR allocate_space_in_inferior (int);
66
67 static struct value *cast_into_complex (struct type *, struct value *);
68
69 static struct fn_field *find_method_list (struct value ** argp, char *method,
70 int offset,
71 struct type *type, int *num_fns,
72 struct type **basetype,
73 int *boffset);
74
75 void _initialize_valops (void);
76
77 /* Flag for whether we want to abandon failed expression evals by default. */
78
79 #if 0
80 static int auto_abandon = 0;
81 #endif
82
83 int overload_resolution = 0;
84
85 /* This boolean tells what gdb should do if a signal is received while in
86 a function called from gdb (call dummy). If set, gdb unwinds the stack
87 and restore the context to what as it was before the call.
88 The default is to stop in the frame where the signal was received. */
89
90 int unwind_on_signal_p = 0;
91 \f
92
93
94 /* Find the address of function name NAME in the inferior. */
95
96 struct value *
97 find_function_in_inferior (char *name)
98 {
99 register struct symbol *sym;
100 sym = lookup_symbol (name, 0, VAR_NAMESPACE, 0, NULL);
101 if (sym != NULL)
102 {
103 if (SYMBOL_CLASS (sym) != LOC_BLOCK)
104 {
105 error ("\"%s\" exists in this program but is not a function.",
106 name);
107 }
108 return value_of_variable (sym, NULL);
109 }
110 else
111 {
112 struct minimal_symbol *msymbol = lookup_minimal_symbol (name, NULL, NULL);
113 if (msymbol != NULL)
114 {
115 struct type *type;
116 CORE_ADDR maddr;
117 type = lookup_pointer_type (builtin_type_char);
118 type = lookup_function_type (type);
119 type = lookup_pointer_type (type);
120 maddr = SYMBOL_VALUE_ADDRESS (msymbol);
121 return value_from_pointer (type, maddr);
122 }
123 else
124 {
125 if (!target_has_execution)
126 error ("evaluation of this expression requires the target program to be active");
127 else
128 error ("evaluation of this expression requires the program to have a function \"%s\".", name);
129 }
130 }
131 }
132
133 /* Allocate NBYTES of space in the inferior using the inferior's malloc
134 and return a value that is a pointer to the allocated space. */
135
136 struct value *
137 value_allocate_space_in_inferior (int len)
138 {
139 struct value *blocklen;
140 struct value *val = find_function_in_inferior ("malloc");
141
142 blocklen = value_from_longest (builtin_type_int, (LONGEST) len);
143 val = call_function_by_hand (val, 1, &blocklen);
144 if (value_logical_not (val))
145 {
146 if (!target_has_execution)
147 error ("No memory available to program now: you need to start the target first");
148 else
149 error ("No memory available to program: call to malloc failed");
150 }
151 return val;
152 }
153
154 static CORE_ADDR
155 allocate_space_in_inferior (int len)
156 {
157 return value_as_long (value_allocate_space_in_inferior (len));
158 }
159
160 /* Cast value ARG2 to type TYPE and return as a value.
161 More general than a C cast: accepts any two types of the same length,
162 and if ARG2 is an lvalue it can be cast into anything at all. */
163 /* In C++, casts may change pointer or object representations. */
164
165 struct value *
166 value_cast (struct type *type, struct value *arg2)
167 {
168 register enum type_code code1;
169 register enum type_code code2;
170 register int scalar;
171 struct type *type2;
172
173 int convert_to_boolean = 0;
174
175 if (VALUE_TYPE (arg2) == type)
176 return arg2;
177
178 CHECK_TYPEDEF (type);
179 code1 = TYPE_CODE (type);
180 COERCE_REF (arg2);
181 type2 = check_typedef (VALUE_TYPE (arg2));
182
183 /* A cast to an undetermined-length array_type, such as (TYPE [])OBJECT,
184 is treated like a cast to (TYPE [N])OBJECT,
185 where N is sizeof(OBJECT)/sizeof(TYPE). */
186 if (code1 == TYPE_CODE_ARRAY)
187 {
188 struct type *element_type = TYPE_TARGET_TYPE (type);
189 unsigned element_length = TYPE_LENGTH (check_typedef (element_type));
190 if (element_length > 0
191 && TYPE_ARRAY_UPPER_BOUND_TYPE (type) == BOUND_CANNOT_BE_DETERMINED)
192 {
193 struct type *range_type = TYPE_INDEX_TYPE (type);
194 int val_length = TYPE_LENGTH (type2);
195 LONGEST low_bound, high_bound, new_length;
196 if (get_discrete_bounds (range_type, &low_bound, &high_bound) < 0)
197 low_bound = 0, high_bound = 0;
198 new_length = val_length / element_length;
199 if (val_length % element_length != 0)
200 warning ("array element type size does not divide object size in cast");
201 /* FIXME-type-allocation: need a way to free this type when we are
202 done with it. */
203 range_type = create_range_type ((struct type *) NULL,
204 TYPE_TARGET_TYPE (range_type),
205 low_bound,
206 new_length + low_bound - 1);
207 VALUE_TYPE (arg2) = create_array_type ((struct type *) NULL,
208 element_type, range_type);
209 return arg2;
210 }
211 }
212
213 if (current_language->c_style_arrays
214 && TYPE_CODE (type2) == TYPE_CODE_ARRAY)
215 arg2 = value_coerce_array (arg2);
216
217 if (TYPE_CODE (type2) == TYPE_CODE_FUNC)
218 arg2 = value_coerce_function (arg2);
219
220 type2 = check_typedef (VALUE_TYPE (arg2));
221 COERCE_VARYING_ARRAY (arg2, type2);
222 code2 = TYPE_CODE (type2);
223
224 if (code1 == TYPE_CODE_COMPLEX)
225 return cast_into_complex (type, arg2);
226 if (code1 == TYPE_CODE_BOOL)
227 {
228 code1 = TYPE_CODE_INT;
229 convert_to_boolean = 1;
230 }
231 if (code1 == TYPE_CODE_CHAR)
232 code1 = TYPE_CODE_INT;
233 if (code2 == TYPE_CODE_BOOL || code2 == TYPE_CODE_CHAR)
234 code2 = TYPE_CODE_INT;
235
236 scalar = (code2 == TYPE_CODE_INT || code2 == TYPE_CODE_FLT
237 || code2 == TYPE_CODE_ENUM || code2 == TYPE_CODE_RANGE);
238
239 if (code1 == TYPE_CODE_STRUCT
240 && code2 == TYPE_CODE_STRUCT
241 && TYPE_NAME (type) != 0)
242 {
243 /* Look in the type of the source to see if it contains the
244 type of the target as a superclass. If so, we'll need to
245 offset the object in addition to changing its type. */
246 struct value *v = search_struct_field (type_name_no_tag (type),
247 arg2, 0, type2, 1);
248 if (v)
249 {
250 VALUE_TYPE (v) = type;
251 return v;
252 }
253 }
254 if (code1 == TYPE_CODE_FLT && scalar)
255 return value_from_double (type, value_as_double (arg2));
256 else if ((code1 == TYPE_CODE_INT || code1 == TYPE_CODE_ENUM
257 || code1 == TYPE_CODE_RANGE)
258 && (scalar || code2 == TYPE_CODE_PTR))
259 {
260 LONGEST longest;
261
262 if (hp_som_som_object_present && /* if target compiled by HP aCC */
263 (code2 == TYPE_CODE_PTR))
264 {
265 unsigned int *ptr;
266 struct value *retvalp;
267
268 switch (TYPE_CODE (TYPE_TARGET_TYPE (type2)))
269 {
270 /* With HP aCC, pointers to data members have a bias */
271 case TYPE_CODE_MEMBER:
272 retvalp = value_from_longest (type, value_as_long (arg2));
273 /* force evaluation */
274 ptr = (unsigned int *) VALUE_CONTENTS (retvalp);
275 *ptr &= ~0x20000000; /* zap 29th bit to remove bias */
276 return retvalp;
277
278 /* While pointers to methods don't really point to a function */
279 case TYPE_CODE_METHOD:
280 error ("Pointers to methods not supported with HP aCC");
281
282 default:
283 break; /* fall out and go to normal handling */
284 }
285 }
286
287 /* When we cast pointers to integers, we mustn't use
288 POINTER_TO_ADDRESS to find the address the pointer
289 represents, as value_as_long would. GDB should evaluate
290 expressions just as the compiler would --- and the compiler
291 sees a cast as a simple reinterpretation of the pointer's
292 bits. */
293 if (code2 == TYPE_CODE_PTR)
294 longest = extract_unsigned_integer (VALUE_CONTENTS (arg2),
295 TYPE_LENGTH (type2));
296 else
297 longest = value_as_long (arg2);
298 return value_from_longest (type, convert_to_boolean ?
299 (LONGEST) (longest ? 1 : 0) : longest);
300 }
301 else if (code1 == TYPE_CODE_PTR && (code2 == TYPE_CODE_INT ||
302 code2 == TYPE_CODE_ENUM ||
303 code2 == TYPE_CODE_RANGE))
304 {
305 /* TYPE_LENGTH (type) is the length of a pointer, but we really
306 want the length of an address! -- we are really dealing with
307 addresses (i.e., gdb representations) not pointers (i.e.,
308 target representations) here.
309
310 This allows things like "print *(int *)0x01000234" to work
311 without printing a misleading message -- which would
312 otherwise occur when dealing with a target having two byte
313 pointers and four byte addresses. */
314
315 int addr_bit = TARGET_ADDR_BIT;
316
317 LONGEST longest = value_as_long (arg2);
318 if (addr_bit < sizeof (LONGEST) * HOST_CHAR_BIT)
319 {
320 if (longest >= ((LONGEST) 1 << addr_bit)
321 || longest <= -((LONGEST) 1 << addr_bit))
322 warning ("value truncated");
323 }
324 return value_from_longest (type, longest);
325 }
326 else if (TYPE_LENGTH (type) == TYPE_LENGTH (type2))
327 {
328 if (code1 == TYPE_CODE_PTR && code2 == TYPE_CODE_PTR)
329 {
330 struct type *t1 = check_typedef (TYPE_TARGET_TYPE (type));
331 struct type *t2 = check_typedef (TYPE_TARGET_TYPE (type2));
332 if (TYPE_CODE (t1) == TYPE_CODE_STRUCT
333 && TYPE_CODE (t2) == TYPE_CODE_STRUCT
334 && !value_logical_not (arg2))
335 {
336 struct value *v;
337
338 /* Look in the type of the source to see if it contains the
339 type of the target as a superclass. If so, we'll need to
340 offset the pointer rather than just change its type. */
341 if (TYPE_NAME (t1) != NULL)
342 {
343 v = search_struct_field (type_name_no_tag (t1),
344 value_ind (arg2), 0, t2, 1);
345 if (v)
346 {
347 v = value_addr (v);
348 VALUE_TYPE (v) = type;
349 return v;
350 }
351 }
352
353 /* Look in the type of the target to see if it contains the
354 type of the source as a superclass. If so, we'll need to
355 offset the pointer rather than just change its type.
356 FIXME: This fails silently with virtual inheritance. */
357 if (TYPE_NAME (t2) != NULL)
358 {
359 v = search_struct_field (type_name_no_tag (t2),
360 value_zero (t1, not_lval), 0, t1, 1);
361 if (v)
362 {
363 struct value *v2 = value_ind (arg2);
364 VALUE_ADDRESS (v2) -= VALUE_ADDRESS (v)
365 + VALUE_OFFSET (v);
366
367 /* JYG: adjust the new pointer value and
368 embedded offset. */
369 v2->aligner.contents[0] -= VALUE_EMBEDDED_OFFSET (v);
370 VALUE_EMBEDDED_OFFSET (v2) = 0;
371
372 v2 = value_addr (v2);
373 VALUE_TYPE (v2) = type;
374 return v2;
375 }
376 }
377 }
378 /* No superclass found, just fall through to change ptr type. */
379 }
380 VALUE_TYPE (arg2) = type;
381 arg2 = value_change_enclosing_type (arg2, type);
382 VALUE_POINTED_TO_OFFSET (arg2) = 0; /* pai: chk_val */
383 return arg2;
384 }
385 else if (chill_varying_type (type))
386 {
387 struct type *range1, *range2, *eltype1, *eltype2;
388 struct value *val;
389 int count1, count2;
390 LONGEST low_bound, high_bound;
391 char *valaddr, *valaddr_data;
392 /* For lint warning about eltype2 possibly uninitialized: */
393 eltype2 = NULL;
394 if (code2 == TYPE_CODE_BITSTRING)
395 error ("not implemented: converting bitstring to varying type");
396 if ((code2 != TYPE_CODE_ARRAY && code2 != TYPE_CODE_STRING)
397 || (eltype1 = check_typedef (TYPE_TARGET_TYPE (TYPE_FIELD_TYPE (type, 1))),
398 eltype2 = check_typedef (TYPE_TARGET_TYPE (type2)),
399 (TYPE_LENGTH (eltype1) != TYPE_LENGTH (eltype2)
400 /* || TYPE_CODE (eltype1) != TYPE_CODE (eltype2) */ )))
401 error ("Invalid conversion to varying type");
402 range1 = TYPE_FIELD_TYPE (TYPE_FIELD_TYPE (type, 1), 0);
403 range2 = TYPE_FIELD_TYPE (type2, 0);
404 if (get_discrete_bounds (range1, &low_bound, &high_bound) < 0)
405 count1 = -1;
406 else
407 count1 = high_bound - low_bound + 1;
408 if (get_discrete_bounds (range2, &low_bound, &high_bound) < 0)
409 count1 = -1, count2 = 0; /* To force error before */
410 else
411 count2 = high_bound - low_bound + 1;
412 if (count2 > count1)
413 error ("target varying type is too small");
414 val = allocate_value (type);
415 valaddr = VALUE_CONTENTS_RAW (val);
416 valaddr_data = valaddr + TYPE_FIELD_BITPOS (type, 1) / 8;
417 /* Set val's __var_length field to count2. */
418 store_signed_integer (valaddr, TYPE_LENGTH (TYPE_FIELD_TYPE (type, 0)),
419 count2);
420 /* Set the __var_data field to count2 elements copied from arg2. */
421 memcpy (valaddr_data, VALUE_CONTENTS (arg2),
422 count2 * TYPE_LENGTH (eltype2));
423 /* Zero the rest of the __var_data field of val. */
424 memset (valaddr_data + count2 * TYPE_LENGTH (eltype2), '\0',
425 (count1 - count2) * TYPE_LENGTH (eltype2));
426 return val;
427 }
428 else if (VALUE_LVAL (arg2) == lval_memory)
429 {
430 return value_at_lazy (type, VALUE_ADDRESS (arg2) + VALUE_OFFSET (arg2),
431 VALUE_BFD_SECTION (arg2));
432 }
433 else if (code1 == TYPE_CODE_VOID)
434 {
435 return value_zero (builtin_type_void, not_lval);
436 }
437 else
438 {
439 error ("Invalid cast.");
440 return 0;
441 }
442 }
443
444 /* Create a value of type TYPE that is zero, and return it. */
445
446 struct value *
447 value_zero (struct type *type, enum lval_type lv)
448 {
449 struct value *val = allocate_value (type);
450
451 memset (VALUE_CONTENTS (val), 0, TYPE_LENGTH (check_typedef (type)));
452 VALUE_LVAL (val) = lv;
453
454 return val;
455 }
456
457 /* Return a value with type TYPE located at ADDR.
458
459 Call value_at only if the data needs to be fetched immediately;
460 if we can be 'lazy' and defer the fetch, perhaps indefinately, call
461 value_at_lazy instead. value_at_lazy simply records the address of
462 the data and sets the lazy-evaluation-required flag. The lazy flag
463 is tested in the VALUE_CONTENTS macro, which is used if and when
464 the contents are actually required.
465
466 Note: value_at does *NOT* handle embedded offsets; perform such
467 adjustments before or after calling it. */
468
469 struct value *
470 value_at (struct type *type, CORE_ADDR addr, asection *sect)
471 {
472 struct value *val;
473
474 if (TYPE_CODE (check_typedef (type)) == TYPE_CODE_VOID)
475 error ("Attempt to dereference a generic pointer.");
476
477 val = allocate_value (type);
478
479 read_memory (addr, VALUE_CONTENTS_ALL_RAW (val), TYPE_LENGTH (type));
480
481 VALUE_LVAL (val) = lval_memory;
482 VALUE_ADDRESS (val) = addr;
483 VALUE_BFD_SECTION (val) = sect;
484
485 return val;
486 }
487
488 /* Return a lazy value with type TYPE located at ADDR (cf. value_at). */
489
490 struct value *
491 value_at_lazy (struct type *type, CORE_ADDR addr, asection *sect)
492 {
493 struct value *val;
494
495 if (TYPE_CODE (check_typedef (type)) == TYPE_CODE_VOID)
496 error ("Attempt to dereference a generic pointer.");
497
498 val = allocate_value (type);
499
500 VALUE_LVAL (val) = lval_memory;
501 VALUE_ADDRESS (val) = addr;
502 VALUE_LAZY (val) = 1;
503 VALUE_BFD_SECTION (val) = sect;
504
505 return val;
506 }
507
508 /* Called only from the VALUE_CONTENTS and VALUE_CONTENTS_ALL macros,
509 if the current data for a variable needs to be loaded into
510 VALUE_CONTENTS(VAL). Fetches the data from the user's process, and
511 clears the lazy flag to indicate that the data in the buffer is valid.
512
513 If the value is zero-length, we avoid calling read_memory, which would
514 abort. We mark the value as fetched anyway -- all 0 bytes of it.
515
516 This function returns a value because it is used in the VALUE_CONTENTS
517 macro as part of an expression, where a void would not work. The
518 value is ignored. */
519
520 int
521 value_fetch_lazy (struct value *val)
522 {
523 CORE_ADDR addr = VALUE_ADDRESS (val) + VALUE_OFFSET (val);
524 int length = TYPE_LENGTH (VALUE_ENCLOSING_TYPE (val));
525
526 struct type *type = VALUE_TYPE (val);
527 if (length)
528 read_memory (addr, VALUE_CONTENTS_ALL_RAW (val), length);
529
530 VALUE_LAZY (val) = 0;
531 return 0;
532 }
533
534
535 /* Store the contents of FROMVAL into the location of TOVAL.
536 Return a new value with the location of TOVAL and contents of FROMVAL. */
537
538 struct value *
539 value_assign (struct value *toval, struct value *fromval)
540 {
541 register struct type *type;
542 struct value *val;
543 char *raw_buffer = (char*) alloca (MAX_REGISTER_RAW_SIZE);
544 int use_buffer = 0;
545
546 if (!toval->modifiable)
547 error ("Left operand of assignment is not a modifiable lvalue.");
548
549 COERCE_REF (toval);
550
551 type = VALUE_TYPE (toval);
552 if (VALUE_LVAL (toval) != lval_internalvar)
553 fromval = value_cast (type, fromval);
554 else
555 COERCE_ARRAY (fromval);
556 CHECK_TYPEDEF (type);
557
558 /* If TOVAL is a special machine register requiring conversion
559 of program values to a special raw format,
560 convert FROMVAL's contents now, with result in `raw_buffer',
561 and set USE_BUFFER to the number of bytes to write. */
562
563 if (VALUE_REGNO (toval) >= 0)
564 {
565 int regno = VALUE_REGNO (toval);
566 if (REGISTER_CONVERTIBLE (regno))
567 {
568 struct type *fromtype = check_typedef (VALUE_TYPE (fromval));
569 REGISTER_CONVERT_TO_RAW (fromtype, regno,
570 VALUE_CONTENTS (fromval), raw_buffer);
571 use_buffer = REGISTER_RAW_SIZE (regno);
572 }
573 }
574
575 switch (VALUE_LVAL (toval))
576 {
577 case lval_internalvar:
578 set_internalvar (VALUE_INTERNALVAR (toval), fromval);
579 val = value_copy (VALUE_INTERNALVAR (toval)->value);
580 val = value_change_enclosing_type (val, VALUE_ENCLOSING_TYPE (fromval));
581 VALUE_EMBEDDED_OFFSET (val) = VALUE_EMBEDDED_OFFSET (fromval);
582 VALUE_POINTED_TO_OFFSET (val) = VALUE_POINTED_TO_OFFSET (fromval);
583 return val;
584
585 case lval_internalvar_component:
586 set_internalvar_component (VALUE_INTERNALVAR (toval),
587 VALUE_OFFSET (toval),
588 VALUE_BITPOS (toval),
589 VALUE_BITSIZE (toval),
590 fromval);
591 break;
592
593 case lval_memory:
594 {
595 char *dest_buffer;
596 CORE_ADDR changed_addr;
597 int changed_len;
598
599 if (VALUE_BITSIZE (toval))
600 {
601 char buffer[sizeof (LONGEST)];
602 /* We assume that the argument to read_memory is in units of
603 host chars. FIXME: Is that correct? */
604 changed_len = (VALUE_BITPOS (toval)
605 + VALUE_BITSIZE (toval)
606 + HOST_CHAR_BIT - 1)
607 / HOST_CHAR_BIT;
608
609 if (changed_len > (int) sizeof (LONGEST))
610 error ("Can't handle bitfields which don't fit in a %d bit word.",
611 (int) sizeof (LONGEST) * HOST_CHAR_BIT);
612
613 read_memory (VALUE_ADDRESS (toval) + VALUE_OFFSET (toval),
614 buffer, changed_len);
615 modify_field (buffer, value_as_long (fromval),
616 VALUE_BITPOS (toval), VALUE_BITSIZE (toval));
617 changed_addr = VALUE_ADDRESS (toval) + VALUE_OFFSET (toval);
618 dest_buffer = buffer;
619 }
620 else if (use_buffer)
621 {
622 changed_addr = VALUE_ADDRESS (toval) + VALUE_OFFSET (toval);
623 changed_len = use_buffer;
624 dest_buffer = raw_buffer;
625 }
626 else
627 {
628 changed_addr = VALUE_ADDRESS (toval) + VALUE_OFFSET (toval);
629 changed_len = TYPE_LENGTH (type);
630 dest_buffer = VALUE_CONTENTS (fromval);
631 }
632
633 write_memory (changed_addr, dest_buffer, changed_len);
634 if (memory_changed_hook)
635 memory_changed_hook (changed_addr, changed_len);
636 }
637 break;
638
639 case lval_register:
640 if (VALUE_BITSIZE (toval))
641 {
642 char buffer[sizeof (LONGEST)];
643 int len =
644 REGISTER_RAW_SIZE (VALUE_REGNO (toval)) - VALUE_OFFSET (toval);
645
646 if (len > (int) sizeof (LONGEST))
647 error ("Can't handle bitfields in registers larger than %d bits.",
648 (int) sizeof (LONGEST) * HOST_CHAR_BIT);
649
650 if (VALUE_BITPOS (toval) + VALUE_BITSIZE (toval)
651 > len * HOST_CHAR_BIT)
652 /* Getting this right would involve being very careful about
653 byte order. */
654 error ("Can't assign to bitfields that cross register "
655 "boundaries.");
656
657 read_register_bytes (VALUE_ADDRESS (toval) + VALUE_OFFSET (toval),
658 buffer, len);
659 modify_field (buffer, value_as_long (fromval),
660 VALUE_BITPOS (toval), VALUE_BITSIZE (toval));
661 write_register_bytes (VALUE_ADDRESS (toval) + VALUE_OFFSET (toval),
662 buffer, len);
663 }
664 else if (use_buffer)
665 write_register_bytes (VALUE_ADDRESS (toval) + VALUE_OFFSET (toval),
666 raw_buffer, use_buffer);
667 else
668 {
669 /* Do any conversion necessary when storing this type to more
670 than one register. */
671 #ifdef REGISTER_CONVERT_FROM_TYPE
672 memcpy (raw_buffer, VALUE_CONTENTS (fromval), TYPE_LENGTH (type));
673 REGISTER_CONVERT_FROM_TYPE (VALUE_REGNO (toval), type, raw_buffer);
674 write_register_bytes (VALUE_ADDRESS (toval) + VALUE_OFFSET (toval),
675 raw_buffer, TYPE_LENGTH (type));
676 #else
677 write_register_bytes (VALUE_ADDRESS (toval) + VALUE_OFFSET (toval),
678 VALUE_CONTENTS (fromval), TYPE_LENGTH (type));
679 #endif
680 }
681 /* Assigning to the stack pointer, frame pointer, and other
682 (architecture and calling convention specific) registers may
683 cause the frame cache to be out of date. We just do this
684 on all assignments to registers for simplicity; I doubt the slowdown
685 matters. */
686 reinit_frame_cache ();
687 break;
688
689 case lval_reg_frame_relative:
690 {
691 /* value is stored in a series of registers in the frame
692 specified by the structure. Copy that value out, modify
693 it, and copy it back in. */
694 int amount_to_copy = (VALUE_BITSIZE (toval) ? 1 : TYPE_LENGTH (type));
695 int reg_size = REGISTER_RAW_SIZE (VALUE_FRAME_REGNUM (toval));
696 int byte_offset = VALUE_OFFSET (toval) % reg_size;
697 int reg_offset = VALUE_OFFSET (toval) / reg_size;
698 int amount_copied;
699
700 /* Make the buffer large enough in all cases. */
701 /* FIXME (alloca): Not safe for very large data types. */
702 char *buffer = (char *) alloca (amount_to_copy
703 + sizeof (LONGEST)
704 + MAX_REGISTER_RAW_SIZE);
705
706 int regno;
707 struct frame_info *frame;
708
709 /* Figure out which frame this is in currently. */
710 for (frame = get_current_frame ();
711 frame && FRAME_FP (frame) != VALUE_FRAME (toval);
712 frame = get_prev_frame (frame))
713 ;
714
715 if (!frame)
716 error ("Value being assigned to is no longer active.");
717
718 amount_to_copy += (reg_size - amount_to_copy % reg_size);
719
720 /* Copy it out. */
721 for ((regno = VALUE_FRAME_REGNUM (toval) + reg_offset,
722 amount_copied = 0);
723 amount_copied < amount_to_copy;
724 amount_copied += reg_size, regno++)
725 {
726 get_saved_register (buffer + amount_copied,
727 (int *) NULL, (CORE_ADDR *) NULL,
728 frame, regno, (enum lval_type *) NULL);
729 }
730
731 /* Modify what needs to be modified. */
732 if (VALUE_BITSIZE (toval))
733 modify_field (buffer + byte_offset,
734 value_as_long (fromval),
735 VALUE_BITPOS (toval), VALUE_BITSIZE (toval));
736 else if (use_buffer)
737 memcpy (buffer + byte_offset, raw_buffer, use_buffer);
738 else
739 memcpy (buffer + byte_offset, VALUE_CONTENTS (fromval),
740 TYPE_LENGTH (type));
741
742 /* Copy it back. */
743 for ((regno = VALUE_FRAME_REGNUM (toval) + reg_offset,
744 amount_copied = 0);
745 amount_copied < amount_to_copy;
746 amount_copied += reg_size, regno++)
747 {
748 enum lval_type lval;
749 CORE_ADDR addr;
750 int optim;
751
752 /* Just find out where to put it. */
753 get_saved_register ((char *) NULL,
754 &optim, &addr, frame, regno, &lval);
755
756 if (optim)
757 error ("Attempt to assign to a value that was optimized out.");
758 if (lval == lval_memory)
759 write_memory (addr, buffer + amount_copied, reg_size);
760 else if (lval == lval_register)
761 write_register_bytes (addr, buffer + amount_copied, reg_size);
762 else
763 error ("Attempt to assign to an unmodifiable value.");
764 }
765
766 if (register_changed_hook)
767 register_changed_hook (-1);
768 }
769 break;
770
771
772 default:
773 error ("Left operand of assignment is not an lvalue.");
774 }
775
776 /* If the field does not entirely fill a LONGEST, then zero the sign bits.
777 If the field is signed, and is negative, then sign extend. */
778 if ((VALUE_BITSIZE (toval) > 0)
779 && (VALUE_BITSIZE (toval) < 8 * (int) sizeof (LONGEST)))
780 {
781 LONGEST fieldval = value_as_long (fromval);
782 LONGEST valmask = (((ULONGEST) 1) << VALUE_BITSIZE (toval)) - 1;
783
784 fieldval &= valmask;
785 if (!TYPE_UNSIGNED (type) && (fieldval & (valmask ^ (valmask >> 1))))
786 fieldval |= ~valmask;
787
788 fromval = value_from_longest (type, fieldval);
789 }
790
791 val = value_copy (toval);
792 memcpy (VALUE_CONTENTS_RAW (val), VALUE_CONTENTS (fromval),
793 TYPE_LENGTH (type));
794 VALUE_TYPE (val) = type;
795 val = value_change_enclosing_type (val, VALUE_ENCLOSING_TYPE (fromval));
796 VALUE_EMBEDDED_OFFSET (val) = VALUE_EMBEDDED_OFFSET (fromval);
797 VALUE_POINTED_TO_OFFSET (val) = VALUE_POINTED_TO_OFFSET (fromval);
798
799 return val;
800 }
801
802 /* Extend a value VAL to COUNT repetitions of its type. */
803
804 struct value *
805 value_repeat (struct value *arg1, int count)
806 {
807 struct value *val;
808
809 if (VALUE_LVAL (arg1) != lval_memory)
810 error ("Only values in memory can be extended with '@'.");
811 if (count < 1)
812 error ("Invalid number %d of repetitions.", count);
813
814 val = allocate_repeat_value (VALUE_ENCLOSING_TYPE (arg1), count);
815
816 read_memory (VALUE_ADDRESS (arg1) + VALUE_OFFSET (arg1),
817 VALUE_CONTENTS_ALL_RAW (val),
818 TYPE_LENGTH (VALUE_ENCLOSING_TYPE (val)));
819 VALUE_LVAL (val) = lval_memory;
820 VALUE_ADDRESS (val) = VALUE_ADDRESS (arg1) + VALUE_OFFSET (arg1);
821
822 return val;
823 }
824
825 struct value *
826 value_of_variable (struct symbol *var, struct block *b)
827 {
828 struct value *val;
829 struct frame_info *frame = NULL;
830
831 if (!b)
832 frame = NULL; /* Use selected frame. */
833 else if (symbol_read_needs_frame (var))
834 {
835 frame = block_innermost_frame (b);
836 if (!frame)
837 {
838 if (BLOCK_FUNCTION (b)
839 && SYMBOL_SOURCE_NAME (BLOCK_FUNCTION (b)))
840 error ("No frame is currently executing in block %s.",
841 SYMBOL_SOURCE_NAME (BLOCK_FUNCTION (b)));
842 else
843 error ("No frame is currently executing in specified block");
844 }
845 }
846
847 val = read_var_value (var, frame);
848 if (!val)
849 error ("Address of symbol \"%s\" is unknown.", SYMBOL_SOURCE_NAME (var));
850
851 return val;
852 }
853
854 /* Given a value which is an array, return a value which is a pointer to its
855 first element, regardless of whether or not the array has a nonzero lower
856 bound.
857
858 FIXME: A previous comment here indicated that this routine should be
859 substracting the array's lower bound. It's not clear to me that this
860 is correct. Given an array subscripting operation, it would certainly
861 work to do the adjustment here, essentially computing:
862
863 (&array[0] - (lowerbound * sizeof array[0])) + (index * sizeof array[0])
864
865 However I believe a more appropriate and logical place to account for
866 the lower bound is to do so in value_subscript, essentially computing:
867
868 (&array[0] + ((index - lowerbound) * sizeof array[0]))
869
870 As further evidence consider what would happen with operations other
871 than array subscripting, where the caller would get back a value that
872 had an address somewhere before the actual first element of the array,
873 and the information about the lower bound would be lost because of
874 the coercion to pointer type.
875 */
876
877 struct value *
878 value_coerce_array (struct value *arg1)
879 {
880 register struct type *type = check_typedef (VALUE_TYPE (arg1));
881
882 if (VALUE_LVAL (arg1) != lval_memory)
883 error ("Attempt to take address of value not located in memory.");
884
885 return value_from_pointer (lookup_pointer_type (TYPE_TARGET_TYPE (type)),
886 (VALUE_ADDRESS (arg1) + VALUE_OFFSET (arg1)));
887 }
888
889 /* Given a value which is a function, return a value which is a pointer
890 to it. */
891
892 struct value *
893 value_coerce_function (struct value *arg1)
894 {
895 struct value *retval;
896
897 if (VALUE_LVAL (arg1) != lval_memory)
898 error ("Attempt to take address of value not located in memory.");
899
900 retval = value_from_pointer (lookup_pointer_type (VALUE_TYPE (arg1)),
901 (VALUE_ADDRESS (arg1) + VALUE_OFFSET (arg1)));
902 VALUE_BFD_SECTION (retval) = VALUE_BFD_SECTION (arg1);
903 return retval;
904 }
905
906 /* Return a pointer value for the object for which ARG1 is the contents. */
907
908 struct value *
909 value_addr (struct value *arg1)
910 {
911 struct value *arg2;
912
913 struct type *type = check_typedef (VALUE_TYPE (arg1));
914 if (TYPE_CODE (type) == TYPE_CODE_REF)
915 {
916 /* Copy the value, but change the type from (T&) to (T*).
917 We keep the same location information, which is efficient,
918 and allows &(&X) to get the location containing the reference. */
919 arg2 = value_copy (arg1);
920 VALUE_TYPE (arg2) = lookup_pointer_type (TYPE_TARGET_TYPE (type));
921 return arg2;
922 }
923 if (TYPE_CODE (type) == TYPE_CODE_FUNC)
924 return value_coerce_function (arg1);
925
926 if (VALUE_LVAL (arg1) != lval_memory)
927 error ("Attempt to take address of value not located in memory.");
928
929 /* Get target memory address */
930 arg2 = value_from_pointer (lookup_pointer_type (VALUE_TYPE (arg1)),
931 (VALUE_ADDRESS (arg1)
932 + VALUE_OFFSET (arg1)
933 + VALUE_EMBEDDED_OFFSET (arg1)));
934
935 /* This may be a pointer to a base subobject; so remember the
936 full derived object's type ... */
937 arg2 = value_change_enclosing_type (arg2, lookup_pointer_type (VALUE_ENCLOSING_TYPE (arg1)));
938 /* ... and also the relative position of the subobject in the full object */
939 VALUE_POINTED_TO_OFFSET (arg2) = VALUE_EMBEDDED_OFFSET (arg1);
940 VALUE_BFD_SECTION (arg2) = VALUE_BFD_SECTION (arg1);
941 return arg2;
942 }
943
944 /* Given a value of a pointer type, apply the C unary * operator to it. */
945
946 struct value *
947 value_ind (struct value *arg1)
948 {
949 struct type *base_type;
950 struct value *arg2;
951
952 COERCE_ARRAY (arg1);
953
954 base_type = check_typedef (VALUE_TYPE (arg1));
955
956 if (TYPE_CODE (base_type) == TYPE_CODE_MEMBER)
957 error ("not implemented: member types in value_ind");
958
959 /* Allow * on an integer so we can cast it to whatever we want.
960 This returns an int, which seems like the most C-like thing
961 to do. "long long" variables are rare enough that
962 BUILTIN_TYPE_LONGEST would seem to be a mistake. */
963 if (TYPE_CODE (base_type) == TYPE_CODE_INT)
964 return value_at (builtin_type_int,
965 (CORE_ADDR) value_as_long (arg1),
966 VALUE_BFD_SECTION (arg1));
967 else if (TYPE_CODE (base_type) == TYPE_CODE_PTR)
968 {
969 struct type *enc_type;
970 /* We may be pointing to something embedded in a larger object */
971 /* Get the real type of the enclosing object */
972 enc_type = check_typedef (VALUE_ENCLOSING_TYPE (arg1));
973 enc_type = TYPE_TARGET_TYPE (enc_type);
974 /* Retrieve the enclosing object pointed to */
975 arg2 = value_at_lazy (enc_type,
976 value_as_address (arg1) - VALUE_POINTED_TO_OFFSET (arg1),
977 VALUE_BFD_SECTION (arg1));
978 /* Re-adjust type */
979 VALUE_TYPE (arg2) = TYPE_TARGET_TYPE (base_type);
980 /* Add embedding info */
981 arg2 = value_change_enclosing_type (arg2, enc_type);
982 VALUE_EMBEDDED_OFFSET (arg2) = VALUE_POINTED_TO_OFFSET (arg1);
983
984 /* We may be pointing to an object of some derived type */
985 arg2 = value_full_object (arg2, NULL, 0, 0, 0);
986 return arg2;
987 }
988
989 error ("Attempt to take contents of a non-pointer value.");
990 return 0; /* For lint -- never reached */
991 }
992 \f
993 /* Pushing small parts of stack frames. */
994
995 /* Push one word (the size of object that a register holds). */
996
997 CORE_ADDR
998 push_word (CORE_ADDR sp, ULONGEST word)
999 {
1000 register int len = REGISTER_SIZE;
1001 char *buffer = alloca (MAX_REGISTER_RAW_SIZE);
1002
1003 store_unsigned_integer (buffer, len, word);
1004 if (INNER_THAN (1, 2))
1005 {
1006 /* stack grows downward */
1007 sp -= len;
1008 write_memory (sp, buffer, len);
1009 }
1010 else
1011 {
1012 /* stack grows upward */
1013 write_memory (sp, buffer, len);
1014 sp += len;
1015 }
1016
1017 return sp;
1018 }
1019
1020 /* Push LEN bytes with data at BUFFER. */
1021
1022 CORE_ADDR
1023 push_bytes (CORE_ADDR sp, char *buffer, int len)
1024 {
1025 if (INNER_THAN (1, 2))
1026 {
1027 /* stack grows downward */
1028 sp -= len;
1029 write_memory (sp, buffer, len);
1030 }
1031 else
1032 {
1033 /* stack grows upward */
1034 write_memory (sp, buffer, len);
1035 sp += len;
1036 }
1037
1038 return sp;
1039 }
1040
1041 #ifndef PARM_BOUNDARY
1042 #define PARM_BOUNDARY (0)
1043 #endif
1044
1045 /* Push onto the stack the specified value VALUE. Pad it correctly for
1046 it to be an argument to a function. */
1047
1048 static CORE_ADDR
1049 value_push (register CORE_ADDR sp, struct value *arg)
1050 {
1051 register int len = TYPE_LENGTH (VALUE_ENCLOSING_TYPE (arg));
1052 register int container_len = len;
1053 register int offset;
1054
1055 /* How big is the container we're going to put this value in? */
1056 if (PARM_BOUNDARY)
1057 container_len = ((len + PARM_BOUNDARY / TARGET_CHAR_BIT - 1)
1058 & ~(PARM_BOUNDARY / TARGET_CHAR_BIT - 1));
1059
1060 /* Are we going to put it at the high or low end of the container? */
1061 if (TARGET_BYTE_ORDER == BFD_ENDIAN_BIG)
1062 offset = container_len - len;
1063 else
1064 offset = 0;
1065
1066 if (INNER_THAN (1, 2))
1067 {
1068 /* stack grows downward */
1069 sp -= container_len;
1070 write_memory (sp + offset, VALUE_CONTENTS_ALL (arg), len);
1071 }
1072 else
1073 {
1074 /* stack grows upward */
1075 write_memory (sp + offset, VALUE_CONTENTS_ALL (arg), len);
1076 sp += container_len;
1077 }
1078
1079 return sp;
1080 }
1081
1082 CORE_ADDR
1083 default_push_arguments (int nargs, struct value **args, CORE_ADDR sp,
1084 int struct_return, CORE_ADDR struct_addr)
1085 {
1086 /* ASSERT ( !struct_return); */
1087 int i;
1088 for (i = nargs - 1; i >= 0; i--)
1089 sp = value_push (sp, args[i]);
1090 return sp;
1091 }
1092
1093
1094 /* Functions to use for the COERCE_FLOAT_TO_DOUBLE gdbarch method.
1095
1096 How you should pass arguments to a function depends on whether it
1097 was defined in K&R style or prototype style. If you define a
1098 function using the K&R syntax that takes a `float' argument, then
1099 callers must pass that argument as a `double'. If you define the
1100 function using the prototype syntax, then you must pass the
1101 argument as a `float', with no promotion.
1102
1103 Unfortunately, on certain older platforms, the debug info doesn't
1104 indicate reliably how each function was defined. A function type's
1105 TYPE_FLAG_PROTOTYPED flag may be clear, even if the function was
1106 defined in prototype style. When calling a function whose
1107 TYPE_FLAG_PROTOTYPED flag is clear, GDB consults the
1108 COERCE_FLOAT_TO_DOUBLE gdbarch method to decide what to do.
1109
1110 For modern targets, it is proper to assume that, if the prototype
1111 flag is clear, that can be trusted: `float' arguments should be
1112 promoted to `double'. You should register the function
1113 `standard_coerce_float_to_double' to get this behavior.
1114
1115 For some older targets, if the prototype flag is clear, that
1116 doesn't tell us anything. So we guess that, if we don't have a
1117 type for the formal parameter (i.e., the first argument to
1118 COERCE_FLOAT_TO_DOUBLE is null), then we should promote it;
1119 otherwise, we should leave it alone. The function
1120 `default_coerce_float_to_double' provides this behavior; it is the
1121 default value, for compatibility with older configurations. */
1122 int
1123 default_coerce_float_to_double (struct type *formal, struct type *actual)
1124 {
1125 return formal == NULL;
1126 }
1127
1128
1129 int
1130 standard_coerce_float_to_double (struct type *formal, struct type *actual)
1131 {
1132 return 1;
1133 }
1134
1135
1136 /* Perform the standard coercions that are specified
1137 for arguments to be passed to C functions.
1138
1139 If PARAM_TYPE is non-NULL, it is the expected parameter type.
1140 IS_PROTOTYPED is non-zero if the function declaration is prototyped. */
1141
1142 static struct value *
1143 value_arg_coerce (struct value *arg, struct type *param_type,
1144 int is_prototyped)
1145 {
1146 register struct type *arg_type = check_typedef (VALUE_TYPE (arg));
1147 register struct type *type
1148 = param_type ? check_typedef (param_type) : arg_type;
1149
1150 switch (TYPE_CODE (type))
1151 {
1152 case TYPE_CODE_REF:
1153 if (TYPE_CODE (arg_type) != TYPE_CODE_REF
1154 && TYPE_CODE (arg_type) != TYPE_CODE_PTR)
1155 {
1156 arg = value_addr (arg);
1157 VALUE_TYPE (arg) = param_type;
1158 return arg;
1159 }
1160 break;
1161 case TYPE_CODE_INT:
1162 case TYPE_CODE_CHAR:
1163 case TYPE_CODE_BOOL:
1164 case TYPE_CODE_ENUM:
1165 /* If we don't have a prototype, coerce to integer type if necessary. */
1166 if (!is_prototyped)
1167 {
1168 if (TYPE_LENGTH (type) < TYPE_LENGTH (builtin_type_int))
1169 type = builtin_type_int;
1170 }
1171 /* Currently all target ABIs require at least the width of an integer
1172 type for an argument. We may have to conditionalize the following
1173 type coercion for future targets. */
1174 if (TYPE_LENGTH (type) < TYPE_LENGTH (builtin_type_int))
1175 type = builtin_type_int;
1176 break;
1177 case TYPE_CODE_FLT:
1178 /* FIXME: We should always convert floats to doubles in the
1179 non-prototyped case. As many debugging formats include
1180 no information about prototyping, we have to live with
1181 COERCE_FLOAT_TO_DOUBLE for now. */
1182 if (!is_prototyped && COERCE_FLOAT_TO_DOUBLE (param_type, arg_type))
1183 {
1184 if (TYPE_LENGTH (type) < TYPE_LENGTH (builtin_type_double))
1185 type = builtin_type_double;
1186 else if (TYPE_LENGTH (type) > TYPE_LENGTH (builtin_type_double))
1187 type = builtin_type_long_double;
1188 }
1189 break;
1190 case TYPE_CODE_FUNC:
1191 type = lookup_pointer_type (type);
1192 break;
1193 case TYPE_CODE_ARRAY:
1194 /* Arrays are coerced to pointers to their first element, unless
1195 they are vectors, in which case we want to leave them alone,
1196 because they are passed by value. */
1197 if (current_language->c_style_arrays)
1198 if (!TYPE_VECTOR (type))
1199 type = lookup_pointer_type (TYPE_TARGET_TYPE (type));
1200 break;
1201 case TYPE_CODE_UNDEF:
1202 case TYPE_CODE_PTR:
1203 case TYPE_CODE_STRUCT:
1204 case TYPE_CODE_UNION:
1205 case TYPE_CODE_VOID:
1206 case TYPE_CODE_SET:
1207 case TYPE_CODE_RANGE:
1208 case TYPE_CODE_STRING:
1209 case TYPE_CODE_BITSTRING:
1210 case TYPE_CODE_ERROR:
1211 case TYPE_CODE_MEMBER:
1212 case TYPE_CODE_METHOD:
1213 case TYPE_CODE_COMPLEX:
1214 default:
1215 break;
1216 }
1217
1218 return value_cast (type, arg);
1219 }
1220
1221 /* Determine a function's address and its return type from its value.
1222 Calls error() if the function is not valid for calling. */
1223
1224 static CORE_ADDR
1225 find_function_addr (struct value *function, struct type **retval_type)
1226 {
1227 register struct type *ftype = check_typedef (VALUE_TYPE (function));
1228 register enum type_code code = TYPE_CODE (ftype);
1229 struct type *value_type;
1230 CORE_ADDR funaddr;
1231
1232 /* If it's a member function, just look at the function
1233 part of it. */
1234
1235 /* Determine address to call. */
1236 if (code == TYPE_CODE_FUNC || code == TYPE_CODE_METHOD)
1237 {
1238 funaddr = VALUE_ADDRESS (function);
1239 value_type = TYPE_TARGET_TYPE (ftype);
1240 }
1241 else if (code == TYPE_CODE_PTR)
1242 {
1243 funaddr = value_as_address (function);
1244 ftype = check_typedef (TYPE_TARGET_TYPE (ftype));
1245 if (TYPE_CODE (ftype) == TYPE_CODE_FUNC
1246 || TYPE_CODE (ftype) == TYPE_CODE_METHOD)
1247 {
1248 funaddr = CONVERT_FROM_FUNC_PTR_ADDR (funaddr);
1249 value_type = TYPE_TARGET_TYPE (ftype);
1250 }
1251 else
1252 value_type = builtin_type_int;
1253 }
1254 else if (code == TYPE_CODE_INT)
1255 {
1256 /* Handle the case of functions lacking debugging info.
1257 Their values are characters since their addresses are char */
1258 if (TYPE_LENGTH (ftype) == 1)
1259 funaddr = value_as_address (value_addr (function));
1260 else
1261 /* Handle integer used as address of a function. */
1262 funaddr = (CORE_ADDR) value_as_long (function);
1263
1264 value_type = builtin_type_int;
1265 }
1266 else
1267 error ("Invalid data type for function to be called.");
1268
1269 *retval_type = value_type;
1270 return funaddr;
1271 }
1272
1273 /* All this stuff with a dummy frame may seem unnecessarily complicated
1274 (why not just save registers in GDB?). The purpose of pushing a dummy
1275 frame which looks just like a real frame is so that if you call a
1276 function and then hit a breakpoint (get a signal, etc), "backtrace"
1277 will look right. Whether the backtrace needs to actually show the
1278 stack at the time the inferior function was called is debatable, but
1279 it certainly needs to not display garbage. So if you are contemplating
1280 making dummy frames be different from normal frames, consider that. */
1281
1282 /* Perform a function call in the inferior.
1283 ARGS is a vector of values of arguments (NARGS of them).
1284 FUNCTION is a value, the function to be called.
1285 Returns a value representing what the function returned.
1286 May fail to return, if a breakpoint or signal is hit
1287 during the execution of the function.
1288
1289 ARGS is modified to contain coerced values. */
1290
1291 static struct value *
1292 hand_function_call (struct value *function, int nargs, struct value **args)
1293 {
1294 register CORE_ADDR sp;
1295 register int i;
1296 int rc;
1297 CORE_ADDR start_sp;
1298 /* CALL_DUMMY is an array of words (REGISTER_SIZE), but each word
1299 is in host byte order. Before calling FIX_CALL_DUMMY, we byteswap it
1300 and remove any extra bytes which might exist because ULONGEST is
1301 bigger than REGISTER_SIZE.
1302
1303 NOTE: This is pretty wierd, as the call dummy is actually a
1304 sequence of instructions. But CISC machines will have
1305 to pack the instructions into REGISTER_SIZE units (and
1306 so will RISC machines for which INSTRUCTION_SIZE is not
1307 REGISTER_SIZE).
1308
1309 NOTE: This is pretty stupid. CALL_DUMMY should be in strict
1310 target byte order. */
1311
1312 static ULONGEST *dummy;
1313 int sizeof_dummy1;
1314 char *dummy1;
1315 CORE_ADDR old_sp;
1316 struct type *value_type;
1317 unsigned char struct_return;
1318 CORE_ADDR struct_addr = 0;
1319 struct inferior_status *inf_status;
1320 struct cleanup *old_chain;
1321 CORE_ADDR funaddr;
1322 int using_gcc; /* Set to version of gcc in use, or zero if not gcc */
1323 CORE_ADDR real_pc;
1324 struct type *param_type = NULL;
1325 struct type *ftype = check_typedef (SYMBOL_TYPE (function));
1326 int n_method_args = 0;
1327
1328 dummy = alloca (SIZEOF_CALL_DUMMY_WORDS);
1329 sizeof_dummy1 = REGISTER_SIZE * SIZEOF_CALL_DUMMY_WORDS / sizeof (ULONGEST);
1330 dummy1 = alloca (sizeof_dummy1);
1331 memcpy (dummy, CALL_DUMMY_WORDS, SIZEOF_CALL_DUMMY_WORDS);
1332
1333 if (!target_has_execution)
1334 noprocess ();
1335
1336 inf_status = save_inferior_status (1);
1337 old_chain = make_cleanup_restore_inferior_status (inf_status);
1338
1339 /* PUSH_DUMMY_FRAME is responsible for saving the inferior registers
1340 (and POP_FRAME for restoring them). (At least on most machines)
1341 they are saved on the stack in the inferior. */
1342 PUSH_DUMMY_FRAME;
1343
1344 old_sp = sp = read_sp ();
1345
1346 if (INNER_THAN (1, 2))
1347 {
1348 /* Stack grows down */
1349 sp -= sizeof_dummy1;
1350 start_sp = sp;
1351 }
1352 else
1353 {
1354 /* Stack grows up */
1355 start_sp = sp;
1356 sp += sizeof_dummy1;
1357 }
1358
1359 funaddr = find_function_addr (function, &value_type);
1360 CHECK_TYPEDEF (value_type);
1361
1362 {
1363 struct block *b = block_for_pc (funaddr);
1364 /* If compiled without -g, assume GCC 2. */
1365 using_gcc = (b == NULL ? 2 : BLOCK_GCC_COMPILED (b));
1366 }
1367
1368 /* Are we returning a value using a structure return or a normal
1369 value return? */
1370
1371 struct_return = using_struct_return (function, funaddr, value_type,
1372 using_gcc);
1373
1374 /* Create a call sequence customized for this function
1375 and the number of arguments for it. */
1376 for (i = 0; i < (int) (SIZEOF_CALL_DUMMY_WORDS / sizeof (dummy[0])); i++)
1377 store_unsigned_integer (&dummy1[i * REGISTER_SIZE],
1378 REGISTER_SIZE,
1379 (ULONGEST) dummy[i]);
1380
1381 #ifdef GDB_TARGET_IS_HPPA
1382 real_pc = FIX_CALL_DUMMY (dummy1, start_sp, funaddr, nargs, args,
1383 value_type, using_gcc);
1384 #else
1385 FIX_CALL_DUMMY (dummy1, start_sp, funaddr, nargs, args,
1386 value_type, using_gcc);
1387 real_pc = start_sp;
1388 #endif
1389
1390 if (CALL_DUMMY_LOCATION == ON_STACK)
1391 {
1392 write_memory (start_sp, (char *) dummy1, sizeof_dummy1);
1393 if (USE_GENERIC_DUMMY_FRAMES)
1394 generic_save_call_dummy_addr (start_sp, start_sp + sizeof_dummy1);
1395 }
1396
1397 if (CALL_DUMMY_LOCATION == BEFORE_TEXT_END)
1398 {
1399 /* Convex Unix prohibits executing in the stack segment. */
1400 /* Hope there is empty room at the top of the text segment. */
1401 extern CORE_ADDR text_end;
1402 static int checked = 0;
1403 if (!checked)
1404 for (start_sp = text_end - sizeof_dummy1; start_sp < text_end; ++start_sp)
1405 if (read_memory_integer (start_sp, 1) != 0)
1406 error ("text segment full -- no place to put call");
1407 checked = 1;
1408 sp = old_sp;
1409 real_pc = text_end - sizeof_dummy1;
1410 write_memory (real_pc, (char *) dummy1, sizeof_dummy1);
1411 if (USE_GENERIC_DUMMY_FRAMES)
1412 generic_save_call_dummy_addr (real_pc, real_pc + sizeof_dummy1);
1413 }
1414
1415 if (CALL_DUMMY_LOCATION == AFTER_TEXT_END)
1416 {
1417 extern CORE_ADDR text_end;
1418 int errcode;
1419 sp = old_sp;
1420 real_pc = text_end;
1421 errcode = target_write_memory (real_pc, (char *) dummy1, sizeof_dummy1);
1422 if (errcode != 0)
1423 error ("Cannot write text segment -- call_function failed");
1424 if (USE_GENERIC_DUMMY_FRAMES)
1425 generic_save_call_dummy_addr (real_pc, real_pc + sizeof_dummy1);
1426 }
1427
1428 if (CALL_DUMMY_LOCATION == AT_ENTRY_POINT)
1429 {
1430 real_pc = funaddr;
1431 if (USE_GENERIC_DUMMY_FRAMES)
1432 /* NOTE: cagney/2002-04-13: The entry point is going to be
1433 modified with a single breakpoint. */
1434 generic_save_call_dummy_addr (CALL_DUMMY_ADDRESS (),
1435 CALL_DUMMY_ADDRESS () + 1);
1436 }
1437
1438 #ifdef lint
1439 sp = old_sp; /* It really is used, for some ifdef's... */
1440 #endif
1441
1442 if (TYPE_CODE (ftype) == TYPE_CODE_METHOD)
1443 {
1444 i = 0;
1445 while (TYPE_CODE (TYPE_ARG_TYPES (ftype)[i]) != TYPE_CODE_VOID)
1446 i++;
1447 n_method_args = i;
1448 if (nargs < i)
1449 error ("too few arguments in method call");
1450 }
1451 else if (nargs < TYPE_NFIELDS (ftype))
1452 error ("too few arguments in function call");
1453
1454 for (i = nargs - 1; i >= 0; i--)
1455 {
1456 /* Assume that methods are always prototyped, unless they are off the
1457 end (which we should only be allowing if there is a ``...'').
1458 FIXME. */
1459 if (TYPE_CODE (ftype) == TYPE_CODE_METHOD)
1460 {
1461 if (i < n_method_args)
1462 args[i] = value_arg_coerce (args[i], TYPE_ARG_TYPES (ftype)[i], 1);
1463 else
1464 args[i] = value_arg_coerce (args[i], NULL, 0);
1465 }
1466
1467 /* If we're off the end of the known arguments, do the standard
1468 promotions. FIXME: if we had a prototype, this should only
1469 be allowed if ... were present. */
1470 if (i >= TYPE_NFIELDS (ftype))
1471 args[i] = value_arg_coerce (args[i], NULL, 0);
1472
1473 else
1474 {
1475 param_type = TYPE_FIELD_TYPE (ftype, i);
1476 args[i] = value_arg_coerce (args[i], param_type, TYPE_PROTOTYPED (ftype));
1477 }
1478
1479 /*elz: this code is to handle the case in which the function to be called
1480 has a pointer to function as parameter and the corresponding actual argument
1481 is the address of a function and not a pointer to function variable.
1482 In aCC compiled code, the calls through pointers to functions (in the body
1483 of the function called by hand) are made via $$dyncall_external which
1484 requires some registers setting, this is taken care of if we call
1485 via a function pointer variable, but not via a function address.
1486 In cc this is not a problem. */
1487
1488 if (using_gcc == 0)
1489 if (param_type)
1490 /* if this parameter is a pointer to function */
1491 if (TYPE_CODE (param_type) == TYPE_CODE_PTR)
1492 if (TYPE_CODE (param_type->target_type) == TYPE_CODE_FUNC)
1493 /* elz: FIXME here should go the test about the compiler used
1494 to compile the target. We want to issue the error
1495 message only if the compiler used was HP's aCC.
1496 If we used HP's cc, then there is no problem and no need
1497 to return at this point */
1498 if (using_gcc == 0) /* && compiler == aCC */
1499 /* go see if the actual parameter is a variable of type
1500 pointer to function or just a function */
1501 if (args[i]->lval == not_lval)
1502 {
1503 char *arg_name;
1504 if (find_pc_partial_function ((CORE_ADDR) args[i]->aligner.contents[0], &arg_name, NULL, NULL))
1505 error ("\
1506 You cannot use function <%s> as argument. \n\
1507 You must use a pointer to function type variable. Command ignored.", arg_name);
1508 }
1509 }
1510
1511 if (REG_STRUCT_HAS_ADDR_P ())
1512 {
1513 /* This is a machine like the sparc, where we may need to pass a
1514 pointer to the structure, not the structure itself. */
1515 for (i = nargs - 1; i >= 0; i--)
1516 {
1517 struct type *arg_type = check_typedef (VALUE_TYPE (args[i]));
1518 if ((TYPE_CODE (arg_type) == TYPE_CODE_STRUCT
1519 || TYPE_CODE (arg_type) == TYPE_CODE_UNION
1520 || TYPE_CODE (arg_type) == TYPE_CODE_ARRAY
1521 || TYPE_CODE (arg_type) == TYPE_CODE_STRING
1522 || TYPE_CODE (arg_type) == TYPE_CODE_BITSTRING
1523 || TYPE_CODE (arg_type) == TYPE_CODE_SET
1524 || (TYPE_CODE (arg_type) == TYPE_CODE_FLT
1525 && TYPE_LENGTH (arg_type) > 8)
1526 )
1527 && REG_STRUCT_HAS_ADDR (using_gcc, arg_type))
1528 {
1529 CORE_ADDR addr;
1530 int len; /* = TYPE_LENGTH (arg_type); */
1531 int aligned_len;
1532 arg_type = check_typedef (VALUE_ENCLOSING_TYPE (args[i]));
1533 len = TYPE_LENGTH (arg_type);
1534
1535 if (STACK_ALIGN_P ())
1536 /* MVS 11/22/96: I think at least some of this
1537 stack_align code is really broken. Better to let
1538 PUSH_ARGUMENTS adjust the stack in a target-defined
1539 manner. */
1540 aligned_len = STACK_ALIGN (len);
1541 else
1542 aligned_len = len;
1543 if (INNER_THAN (1, 2))
1544 {
1545 /* stack grows downward */
1546 sp -= aligned_len;
1547 /* ... so the address of the thing we push is the
1548 stack pointer after we push it. */
1549 addr = sp;
1550 }
1551 else
1552 {
1553 /* The stack grows up, so the address of the thing
1554 we push is the stack pointer before we push it. */
1555 addr = sp;
1556 sp += aligned_len;
1557 }
1558 /* Push the structure. */
1559 write_memory (addr, VALUE_CONTENTS_ALL (args[i]), len);
1560 /* The value we're going to pass is the address of the
1561 thing we just pushed. */
1562 /*args[i] = value_from_longest (lookup_pointer_type (value_type),
1563 (LONGEST) addr); */
1564 args[i] = value_from_pointer (lookup_pointer_type (arg_type),
1565 addr);
1566 }
1567 }
1568 }
1569
1570
1571 /* Reserve space for the return structure to be written on the
1572 stack, if necessary */
1573
1574 if (struct_return)
1575 {
1576 int len = TYPE_LENGTH (value_type);
1577 if (STACK_ALIGN_P ())
1578 /* MVS 11/22/96: I think at least some of this stack_align
1579 code is really broken. Better to let PUSH_ARGUMENTS adjust
1580 the stack in a target-defined manner. */
1581 len = STACK_ALIGN (len);
1582 if (INNER_THAN (1, 2))
1583 {
1584 /* stack grows downward */
1585 sp -= len;
1586 struct_addr = sp;
1587 }
1588 else
1589 {
1590 /* stack grows upward */
1591 struct_addr = sp;
1592 sp += len;
1593 }
1594 }
1595
1596 /* elz: on HPPA no need for this extra alignment, maybe it is needed
1597 on other architectures. This is because all the alignment is
1598 taken care of in the above code (ifdef REG_STRUCT_HAS_ADDR) and
1599 in hppa_push_arguments */
1600 if (EXTRA_STACK_ALIGNMENT_NEEDED)
1601 {
1602 /* MVS 11/22/96: I think at least some of this stack_align code
1603 is really broken. Better to let PUSH_ARGUMENTS adjust the
1604 stack in a target-defined manner. */
1605 if (STACK_ALIGN_P () && INNER_THAN (1, 2))
1606 {
1607 /* If stack grows down, we must leave a hole at the top. */
1608 int len = 0;
1609
1610 for (i = nargs - 1; i >= 0; i--)
1611 len += TYPE_LENGTH (VALUE_ENCLOSING_TYPE (args[i]));
1612 if (CALL_DUMMY_STACK_ADJUST_P)
1613 len += CALL_DUMMY_STACK_ADJUST;
1614 sp -= STACK_ALIGN (len) - len;
1615 }
1616 }
1617
1618 sp = PUSH_ARGUMENTS (nargs, args, sp, struct_return, struct_addr);
1619
1620 if (PUSH_RETURN_ADDRESS_P ())
1621 /* for targets that use no CALL_DUMMY */
1622 /* There are a number of targets now which actually don't write
1623 any CALL_DUMMY instructions into the target, but instead just
1624 save the machine state, push the arguments, and jump directly
1625 to the callee function. Since this doesn't actually involve
1626 executing a JSR/BSR instruction, the return address must be set
1627 up by hand, either by pushing onto the stack or copying into a
1628 return-address register as appropriate. Formerly this has been
1629 done in PUSH_ARGUMENTS, but that's overloading its
1630 functionality a bit, so I'm making it explicit to do it here. */
1631 sp = PUSH_RETURN_ADDRESS (real_pc, sp);
1632
1633 if (STACK_ALIGN_P () && !INNER_THAN (1, 2))
1634 {
1635 /* If stack grows up, we must leave a hole at the bottom, note
1636 that sp already has been advanced for the arguments! */
1637 if (CALL_DUMMY_STACK_ADJUST_P)
1638 sp += CALL_DUMMY_STACK_ADJUST;
1639 sp = STACK_ALIGN (sp);
1640 }
1641
1642 /* XXX This seems wrong. For stacks that grow down we shouldn't do
1643 anything here! */
1644 /* MVS 11/22/96: I think at least some of this stack_align code is
1645 really broken. Better to let PUSH_ARGUMENTS adjust the stack in
1646 a target-defined manner. */
1647 if (CALL_DUMMY_STACK_ADJUST_P)
1648 if (INNER_THAN (1, 2))
1649 {
1650 /* stack grows downward */
1651 sp -= CALL_DUMMY_STACK_ADJUST;
1652 }
1653
1654 /* Store the address at which the structure is supposed to be
1655 written. Note that this (and the code which reserved the space
1656 above) assumes that gcc was used to compile this function. Since
1657 it doesn't cost us anything but space and if the function is pcc
1658 it will ignore this value, we will make that assumption.
1659
1660 Also note that on some machines (like the sparc) pcc uses a
1661 convention like gcc's. */
1662
1663 if (struct_return)
1664 STORE_STRUCT_RETURN (struct_addr, sp);
1665
1666 /* Write the stack pointer. This is here because the statements above
1667 might fool with it. On SPARC, this write also stores the register
1668 window into the right place in the new stack frame, which otherwise
1669 wouldn't happen. (See store_inferior_registers in sparc-nat.c.) */
1670 write_sp (sp);
1671
1672 if (SAVE_DUMMY_FRAME_TOS_P ())
1673 SAVE_DUMMY_FRAME_TOS (sp);
1674
1675 {
1676 char *retbuf = (char*) alloca (REGISTER_BYTES);
1677 char *name;
1678 struct symbol *symbol;
1679
1680 name = NULL;
1681 symbol = find_pc_function (funaddr);
1682 if (symbol)
1683 {
1684 name = SYMBOL_SOURCE_NAME (symbol);
1685 }
1686 else
1687 {
1688 /* Try the minimal symbols. */
1689 struct minimal_symbol *msymbol = lookup_minimal_symbol_by_pc (funaddr);
1690
1691 if (msymbol)
1692 {
1693 name = SYMBOL_SOURCE_NAME (msymbol);
1694 }
1695 }
1696 if (name == NULL)
1697 {
1698 char format[80];
1699 sprintf (format, "at %s", local_hex_format ());
1700 name = alloca (80);
1701 /* FIXME-32x64: assumes funaddr fits in a long. */
1702 sprintf (name, format, (unsigned long) funaddr);
1703 }
1704
1705 /* Execute the stack dummy routine, calling FUNCTION.
1706 When it is done, discard the empty frame
1707 after storing the contents of all regs into retbuf. */
1708 rc = run_stack_dummy (real_pc + CALL_DUMMY_START_OFFSET, retbuf);
1709
1710 if (rc == 1)
1711 {
1712 /* We stopped inside the FUNCTION because of a random signal.
1713 Further execution of the FUNCTION is not allowed. */
1714
1715 if (unwind_on_signal_p)
1716 {
1717 /* The user wants the context restored. */
1718
1719 /* We must get back to the frame we were before the dummy call. */
1720 POP_FRAME;
1721
1722 /* FIXME: Insert a bunch of wrap_here; name can be very long if it's
1723 a C++ name with arguments and stuff. */
1724 error ("\
1725 The program being debugged was signaled while in a function called from GDB.\n\
1726 GDB has restored the context to what it was before the call.\n\
1727 To change this behavior use \"set unwindonsignal off\"\n\
1728 Evaluation of the expression containing the function (%s) will be abandoned.",
1729 name);
1730 }
1731 else
1732 {
1733 /* The user wants to stay in the frame where we stopped (default).*/
1734
1735 /* If we did the cleanups, we would print a spurious error
1736 message (Unable to restore previously selected frame),
1737 would write the registers from the inf_status (which is
1738 wrong), and would do other wrong things. */
1739 discard_cleanups (old_chain);
1740 discard_inferior_status (inf_status);
1741
1742 /* FIXME: Insert a bunch of wrap_here; name can be very long if it's
1743 a C++ name with arguments and stuff. */
1744 error ("\
1745 The program being debugged was signaled while in a function called from GDB.\n\
1746 GDB remains in the frame where the signal was received.\n\
1747 To change this behavior use \"set unwindonsignal on\"\n\
1748 Evaluation of the expression containing the function (%s) will be abandoned.",
1749 name);
1750 }
1751 }
1752
1753 if (rc == 2)
1754 {
1755 /* We hit a breakpoint inside the FUNCTION. */
1756
1757 /* If we did the cleanups, we would print a spurious error
1758 message (Unable to restore previously selected frame),
1759 would write the registers from the inf_status (which is
1760 wrong), and would do other wrong things. */
1761 discard_cleanups (old_chain);
1762 discard_inferior_status (inf_status);
1763
1764 /* The following error message used to say "The expression
1765 which contained the function call has been discarded." It
1766 is a hard concept to explain in a few words. Ideally, GDB
1767 would be able to resume evaluation of the expression when
1768 the function finally is done executing. Perhaps someday
1769 this will be implemented (it would not be easy). */
1770
1771 /* FIXME: Insert a bunch of wrap_here; name can be very long if it's
1772 a C++ name with arguments and stuff. */
1773 error ("\
1774 The program being debugged stopped while in a function called from GDB.\n\
1775 When the function (%s) is done executing, GDB will silently\n\
1776 stop (instead of continuing to evaluate the expression containing\n\
1777 the function call).", name);
1778 }
1779
1780 /* If we get here the called FUNCTION run to completion. */
1781 do_cleanups (old_chain);
1782
1783 /* Figure out the value returned by the function. */
1784 /* elz: I defined this new macro for the hppa architecture only.
1785 this gives us a way to get the value returned by the function from the stack,
1786 at the same address we told the function to put it.
1787 We cannot assume on the pa that r28 still contains the address of the returned
1788 structure. Usually this will be overwritten by the callee.
1789 I don't know about other architectures, so I defined this macro
1790 */
1791
1792 #ifdef VALUE_RETURNED_FROM_STACK
1793 if (struct_return)
1794 return (struct value *) VALUE_RETURNED_FROM_STACK (value_type, struct_addr);
1795 #endif
1796
1797 return value_being_returned (value_type, retbuf, struct_return);
1798 }
1799 }
1800
1801 struct value *
1802 call_function_by_hand (struct value *function, int nargs, struct value **args)
1803 {
1804 if (CALL_DUMMY_P)
1805 {
1806 return hand_function_call (function, nargs, args);
1807 }
1808 else
1809 {
1810 error ("Cannot invoke functions on this machine.");
1811 }
1812 }
1813 \f
1814
1815
1816 /* Create a value for an array by allocating space in the inferior, copying
1817 the data into that space, and then setting up an array value.
1818
1819 The array bounds are set from LOWBOUND and HIGHBOUND, and the array is
1820 populated from the values passed in ELEMVEC.
1821
1822 The element type of the array is inherited from the type of the
1823 first element, and all elements must have the same size (though we
1824 don't currently enforce any restriction on their types). */
1825
1826 struct value *
1827 value_array (int lowbound, int highbound, struct value **elemvec)
1828 {
1829 int nelem;
1830 int idx;
1831 unsigned int typelength;
1832 struct value *val;
1833 struct type *rangetype;
1834 struct type *arraytype;
1835 CORE_ADDR addr;
1836
1837 /* Validate that the bounds are reasonable and that each of the elements
1838 have the same size. */
1839
1840 nelem = highbound - lowbound + 1;
1841 if (nelem <= 0)
1842 {
1843 error ("bad array bounds (%d, %d)", lowbound, highbound);
1844 }
1845 typelength = TYPE_LENGTH (VALUE_ENCLOSING_TYPE (elemvec[0]));
1846 for (idx = 1; idx < nelem; idx++)
1847 {
1848 if (TYPE_LENGTH (VALUE_ENCLOSING_TYPE (elemvec[idx])) != typelength)
1849 {
1850 error ("array elements must all be the same size");
1851 }
1852 }
1853
1854 rangetype = create_range_type ((struct type *) NULL, builtin_type_int,
1855 lowbound, highbound);
1856 arraytype = create_array_type ((struct type *) NULL,
1857 VALUE_ENCLOSING_TYPE (elemvec[0]), rangetype);
1858
1859 if (!current_language->c_style_arrays)
1860 {
1861 val = allocate_value (arraytype);
1862 for (idx = 0; idx < nelem; idx++)
1863 {
1864 memcpy (VALUE_CONTENTS_ALL_RAW (val) + (idx * typelength),
1865 VALUE_CONTENTS_ALL (elemvec[idx]),
1866 typelength);
1867 }
1868 VALUE_BFD_SECTION (val) = VALUE_BFD_SECTION (elemvec[0]);
1869 return val;
1870 }
1871
1872 /* Allocate space to store the array in the inferior, and then initialize
1873 it by copying in each element. FIXME: Is it worth it to create a
1874 local buffer in which to collect each value and then write all the
1875 bytes in one operation? */
1876
1877 addr = allocate_space_in_inferior (nelem * typelength);
1878 for (idx = 0; idx < nelem; idx++)
1879 {
1880 write_memory (addr + (idx * typelength), VALUE_CONTENTS_ALL (elemvec[idx]),
1881 typelength);
1882 }
1883
1884 /* Create the array type and set up an array value to be evaluated lazily. */
1885
1886 val = value_at_lazy (arraytype, addr, VALUE_BFD_SECTION (elemvec[0]));
1887 return (val);
1888 }
1889
1890 /* Create a value for a string constant by allocating space in the inferior,
1891 copying the data into that space, and returning the address with type
1892 TYPE_CODE_STRING. PTR points to the string constant data; LEN is number
1893 of characters.
1894 Note that string types are like array of char types with a lower bound of
1895 zero and an upper bound of LEN - 1. Also note that the string may contain
1896 embedded null bytes. */
1897
1898 struct value *
1899 value_string (char *ptr, int len)
1900 {
1901 struct value *val;
1902 int lowbound = current_language->string_lower_bound;
1903 struct type *rangetype = create_range_type ((struct type *) NULL,
1904 builtin_type_int,
1905 lowbound, len + lowbound - 1);
1906 struct type *stringtype
1907 = create_string_type ((struct type *) NULL, rangetype);
1908 CORE_ADDR addr;
1909
1910 if (current_language->c_style_arrays == 0)
1911 {
1912 val = allocate_value (stringtype);
1913 memcpy (VALUE_CONTENTS_RAW (val), ptr, len);
1914 return val;
1915 }
1916
1917
1918 /* Allocate space to store the string in the inferior, and then
1919 copy LEN bytes from PTR in gdb to that address in the inferior. */
1920
1921 addr = allocate_space_in_inferior (len);
1922 write_memory (addr, ptr, len);
1923
1924 val = value_at_lazy (stringtype, addr, NULL);
1925 return (val);
1926 }
1927
1928 struct value *
1929 value_bitstring (char *ptr, int len)
1930 {
1931 struct value *val;
1932 struct type *domain_type = create_range_type (NULL, builtin_type_int,
1933 0, len - 1);
1934 struct type *type = create_set_type ((struct type *) NULL, domain_type);
1935 TYPE_CODE (type) = TYPE_CODE_BITSTRING;
1936 val = allocate_value (type);
1937 memcpy (VALUE_CONTENTS_RAW (val), ptr, TYPE_LENGTH (type));
1938 return val;
1939 }
1940 \f
1941 /* See if we can pass arguments in T2 to a function which takes arguments
1942 of types T1. Both t1 and t2 are NULL-terminated vectors. If some
1943 arguments need coercion of some sort, then the coerced values are written
1944 into T2. Return value is 0 if the arguments could be matched, or the
1945 position at which they differ if not.
1946
1947 STATICP is nonzero if the T1 argument list came from a
1948 static member function.
1949
1950 For non-static member functions, we ignore the first argument,
1951 which is the type of the instance variable. This is because we want
1952 to handle calls with objects from derived classes. This is not
1953 entirely correct: we should actually check to make sure that a
1954 requested operation is type secure, shouldn't we? FIXME. */
1955
1956 static int
1957 typecmp (int staticp, struct type *t1[], struct value *t2[])
1958 {
1959 int i;
1960
1961 if (t2 == 0)
1962 return 1;
1963 if (staticp && t1 == 0)
1964 return t2[1] != 0;
1965 if (t1 == 0)
1966 return 1;
1967 if (t1[!staticp] == 0)
1968 return 0;
1969 if (TYPE_CODE (t1[0]) == TYPE_CODE_VOID)
1970 return 0;
1971 /* Skip ``this'' argument if applicable. T2 will always include THIS. */
1972 if (staticp)
1973 t2++;
1974 for (i = !staticp; t1[i] && TYPE_CODE (t1[i]) != TYPE_CODE_VOID; i++)
1975 {
1976 struct type *tt1, *tt2;
1977 if (!t2[i])
1978 return i + 1;
1979 tt1 = check_typedef (t1[i]);
1980 tt2 = check_typedef (VALUE_TYPE (t2[i]));
1981 if (TYPE_CODE (tt1) == TYPE_CODE_REF
1982 /* We should be doing hairy argument matching, as below. */
1983 && (TYPE_CODE (check_typedef (TYPE_TARGET_TYPE (tt1))) == TYPE_CODE (tt2)))
1984 {
1985 if (TYPE_CODE (tt2) == TYPE_CODE_ARRAY)
1986 t2[i] = value_coerce_array (t2[i]);
1987 else
1988 t2[i] = value_addr (t2[i]);
1989 continue;
1990 }
1991
1992 /* djb - 20000715 - Until the new type structure is in the
1993 place, and we can attempt things like implicit conversions,
1994 we need to do this so you can take something like a map<const
1995 char *>, and properly access map["hello"], because the
1996 argument to [] will be a reference to a pointer to a char,
1997 and the argument will be a pointer to a char. */
1998 while ( TYPE_CODE(tt1) == TYPE_CODE_REF ||
1999 TYPE_CODE (tt1) == TYPE_CODE_PTR)
2000 {
2001 tt1 = check_typedef( TYPE_TARGET_TYPE(tt1) );
2002 }
2003 while ( TYPE_CODE(tt2) == TYPE_CODE_ARRAY ||
2004 TYPE_CODE(tt2) == TYPE_CODE_PTR ||
2005 TYPE_CODE(tt2) == TYPE_CODE_REF)
2006 {
2007 tt2 = check_typedef( TYPE_TARGET_TYPE(tt2) );
2008 }
2009 if (TYPE_CODE (tt1) == TYPE_CODE (tt2))
2010 continue;
2011 /* Array to pointer is a `trivial conversion' according to the ARM. */
2012
2013 /* We should be doing much hairier argument matching (see section 13.2
2014 of the ARM), but as a quick kludge, just check for the same type
2015 code. */
2016 if (TYPE_CODE (t1[i]) != TYPE_CODE (VALUE_TYPE (t2[i])))
2017 return i + 1;
2018 }
2019 if (!t1[i])
2020 return 0;
2021 return t2[i] ? i + 1 : 0;
2022 }
2023
2024 /* Helper function used by value_struct_elt to recurse through baseclasses.
2025 Look for a field NAME in ARG1. Adjust the address of ARG1 by OFFSET bytes,
2026 and search in it assuming it has (class) type TYPE.
2027 If found, return value, else return NULL.
2028
2029 If LOOKING_FOR_BASECLASS, then instead of looking for struct fields,
2030 look for a baseclass named NAME. */
2031
2032 static struct value *
2033 search_struct_field (char *name, struct value *arg1, int offset,
2034 register struct type *type, int looking_for_baseclass)
2035 {
2036 int i;
2037 int nbases = TYPE_N_BASECLASSES (type);
2038
2039 CHECK_TYPEDEF (type);
2040
2041 if (!looking_for_baseclass)
2042 for (i = TYPE_NFIELDS (type) - 1; i >= nbases; i--)
2043 {
2044 char *t_field_name = TYPE_FIELD_NAME (type, i);
2045
2046 if (t_field_name && (strcmp_iw (t_field_name, name) == 0))
2047 {
2048 struct value *v;
2049 if (TYPE_FIELD_STATIC (type, i))
2050 v = value_static_field (type, i);
2051 else
2052 v = value_primitive_field (arg1, offset, i, type);
2053 if (v == 0)
2054 error ("there is no field named %s", name);
2055 return v;
2056 }
2057
2058 if (t_field_name
2059 && (t_field_name[0] == '\0'
2060 || (TYPE_CODE (type) == TYPE_CODE_UNION
2061 && (strcmp_iw (t_field_name, "else") == 0))))
2062 {
2063 struct type *field_type = TYPE_FIELD_TYPE (type, i);
2064 if (TYPE_CODE (field_type) == TYPE_CODE_UNION
2065 || TYPE_CODE (field_type) == TYPE_CODE_STRUCT)
2066 {
2067 /* Look for a match through the fields of an anonymous union,
2068 or anonymous struct. C++ provides anonymous unions.
2069
2070 In the GNU Chill implementation of variant record types,
2071 each <alternative field> has an (anonymous) union type,
2072 each member of the union represents a <variant alternative>.
2073 Each <variant alternative> is represented as a struct,
2074 with a member for each <variant field>. */
2075
2076 struct value *v;
2077 int new_offset = offset;
2078
2079 /* This is pretty gross. In G++, the offset in an anonymous
2080 union is relative to the beginning of the enclosing struct.
2081 In the GNU Chill implementation of variant records,
2082 the bitpos is zero in an anonymous union field, so we
2083 have to add the offset of the union here. */
2084 if (TYPE_CODE (field_type) == TYPE_CODE_STRUCT
2085 || (TYPE_NFIELDS (field_type) > 0
2086 && TYPE_FIELD_BITPOS (field_type, 0) == 0))
2087 new_offset += TYPE_FIELD_BITPOS (type, i) / 8;
2088
2089 v = search_struct_field (name, arg1, new_offset, field_type,
2090 looking_for_baseclass);
2091 if (v)
2092 return v;
2093 }
2094 }
2095 }
2096
2097 for (i = 0; i < nbases; i++)
2098 {
2099 struct value *v;
2100 struct type *basetype = check_typedef (TYPE_BASECLASS (type, i));
2101 /* If we are looking for baseclasses, this is what we get when we
2102 hit them. But it could happen that the base part's member name
2103 is not yet filled in. */
2104 int found_baseclass = (looking_for_baseclass
2105 && TYPE_BASECLASS_NAME (type, i) != NULL
2106 && (strcmp_iw (name, TYPE_BASECLASS_NAME (type, i)) == 0));
2107
2108 if (BASETYPE_VIA_VIRTUAL (type, i))
2109 {
2110 int boffset;
2111 struct value *v2 = allocate_value (basetype);
2112
2113 boffset = baseclass_offset (type, i,
2114 VALUE_CONTENTS (arg1) + offset,
2115 VALUE_ADDRESS (arg1)
2116 + VALUE_OFFSET (arg1) + offset);
2117 if (boffset == -1)
2118 error ("virtual baseclass botch");
2119
2120 /* The virtual base class pointer might have been clobbered by the
2121 user program. Make sure that it still points to a valid memory
2122 location. */
2123
2124 boffset += offset;
2125 if (boffset < 0 || boffset >= TYPE_LENGTH (type))
2126 {
2127 CORE_ADDR base_addr;
2128
2129 base_addr = VALUE_ADDRESS (arg1) + VALUE_OFFSET (arg1) + boffset;
2130 if (target_read_memory (base_addr, VALUE_CONTENTS_RAW (v2),
2131 TYPE_LENGTH (basetype)) != 0)
2132 error ("virtual baseclass botch");
2133 VALUE_LVAL (v2) = lval_memory;
2134 VALUE_ADDRESS (v2) = base_addr;
2135 }
2136 else
2137 {
2138 VALUE_LVAL (v2) = VALUE_LVAL (arg1);
2139 VALUE_ADDRESS (v2) = VALUE_ADDRESS (arg1);
2140 VALUE_OFFSET (v2) = VALUE_OFFSET (arg1) + boffset;
2141 if (VALUE_LAZY (arg1))
2142 VALUE_LAZY (v2) = 1;
2143 else
2144 memcpy (VALUE_CONTENTS_RAW (v2),
2145 VALUE_CONTENTS_RAW (arg1) + boffset,
2146 TYPE_LENGTH (basetype));
2147 }
2148
2149 if (found_baseclass)
2150 return v2;
2151 v = search_struct_field (name, v2, 0, TYPE_BASECLASS (type, i),
2152 looking_for_baseclass);
2153 }
2154 else if (found_baseclass)
2155 v = value_primitive_field (arg1, offset, i, type);
2156 else
2157 v = search_struct_field (name, arg1,
2158 offset + TYPE_BASECLASS_BITPOS (type, i) / 8,
2159 basetype, looking_for_baseclass);
2160 if (v)
2161 return v;
2162 }
2163 return NULL;
2164 }
2165
2166
2167 /* Return the offset (in bytes) of the virtual base of type BASETYPE
2168 * in an object pointed to by VALADDR (on the host), assumed to be of
2169 * type TYPE. OFFSET is number of bytes beyond start of ARG to start
2170 * looking (in case VALADDR is the contents of an enclosing object).
2171 *
2172 * This routine recurses on the primary base of the derived class because
2173 * the virtual base entries of the primary base appear before the other
2174 * virtual base entries.
2175 *
2176 * If the virtual base is not found, a negative integer is returned.
2177 * The magnitude of the negative integer is the number of entries in
2178 * the virtual table to skip over (entries corresponding to various
2179 * ancestral classes in the chain of primary bases).
2180 *
2181 * Important: This assumes the HP / Taligent C++ runtime
2182 * conventions. Use baseclass_offset() instead to deal with g++
2183 * conventions. */
2184
2185 void
2186 find_rt_vbase_offset (struct type *type, struct type *basetype, char *valaddr,
2187 int offset, int *boffset_p, int *skip_p)
2188 {
2189 int boffset; /* offset of virtual base */
2190 int index; /* displacement to use in virtual table */
2191 int skip;
2192
2193 struct value *vp;
2194 CORE_ADDR vtbl; /* the virtual table pointer */
2195 struct type *pbc; /* the primary base class */
2196
2197 /* Look for the virtual base recursively in the primary base, first.
2198 * This is because the derived class object and its primary base
2199 * subobject share the primary virtual table. */
2200
2201 boffset = 0;
2202 pbc = TYPE_PRIMARY_BASE (type);
2203 if (pbc)
2204 {
2205 find_rt_vbase_offset (pbc, basetype, valaddr, offset, &boffset, &skip);
2206 if (skip < 0)
2207 {
2208 *boffset_p = boffset;
2209 *skip_p = -1;
2210 return;
2211 }
2212 }
2213 else
2214 skip = 0;
2215
2216
2217 /* Find the index of the virtual base according to HP/Taligent
2218 runtime spec. (Depth-first, left-to-right.) */
2219 index = virtual_base_index_skip_primaries (basetype, type);
2220
2221 if (index < 0)
2222 {
2223 *skip_p = skip + virtual_base_list_length_skip_primaries (type);
2224 *boffset_p = 0;
2225 return;
2226 }
2227
2228 /* pai: FIXME -- 32x64 possible problem */
2229 /* First word (4 bytes) in object layout is the vtable pointer */
2230 vtbl = *(CORE_ADDR *) (valaddr + offset);
2231
2232 /* Before the constructor is invoked, things are usually zero'd out. */
2233 if (vtbl == 0)
2234 error ("Couldn't find virtual table -- object may not be constructed yet.");
2235
2236
2237 /* Find virtual base's offset -- jump over entries for primary base
2238 * ancestors, then use the index computed above. But also adjust by
2239 * HP_ACC_VBASE_START for the vtable slots before the start of the
2240 * virtual base entries. Offset is negative -- virtual base entries
2241 * appear _before_ the address point of the virtual table. */
2242
2243 /* pai: FIXME -- 32x64 problem, if word = 8 bytes, change multiplier
2244 & use long type */
2245
2246 /* epstein : FIXME -- added param for overlay section. May not be correct */
2247 vp = value_at (builtin_type_int, vtbl + 4 * (-skip - index - HP_ACC_VBASE_START), NULL);
2248 boffset = value_as_long (vp);
2249 *skip_p = -1;
2250 *boffset_p = boffset;
2251 return;
2252 }
2253
2254
2255 /* Helper function used by value_struct_elt to recurse through baseclasses.
2256 Look for a field NAME in ARG1. Adjust the address of ARG1 by OFFSET bytes,
2257 and search in it assuming it has (class) type TYPE.
2258 If found, return value, else if name matched and args not return (value)-1,
2259 else return NULL. */
2260
2261 static struct value *
2262 search_struct_method (char *name, struct value **arg1p,
2263 struct value **args, int offset,
2264 int *static_memfuncp, register struct type *type)
2265 {
2266 int i;
2267 struct value *v;
2268 int name_matched = 0;
2269 char dem_opname[64];
2270
2271 CHECK_TYPEDEF (type);
2272 for (i = TYPE_NFN_FIELDS (type) - 1; i >= 0; i--)
2273 {
2274 char *t_field_name = TYPE_FN_FIELDLIST_NAME (type, i);
2275 /* FIXME! May need to check for ARM demangling here */
2276 if (strncmp (t_field_name, "__", 2) == 0 ||
2277 strncmp (t_field_name, "op", 2) == 0 ||
2278 strncmp (t_field_name, "type", 4) == 0)
2279 {
2280 if (cplus_demangle_opname (t_field_name, dem_opname, DMGL_ANSI))
2281 t_field_name = dem_opname;
2282 else if (cplus_demangle_opname (t_field_name, dem_opname, 0))
2283 t_field_name = dem_opname;
2284 }
2285 if (t_field_name && (strcmp_iw (t_field_name, name) == 0))
2286 {
2287 int j = TYPE_FN_FIELDLIST_LENGTH (type, i) - 1;
2288 struct fn_field *f = TYPE_FN_FIELDLIST1 (type, i);
2289 name_matched = 1;
2290
2291 if (j > 0 && args == 0)
2292 error ("cannot resolve overloaded method `%s': no arguments supplied", name);
2293 else if (j == 0 && args == 0)
2294 {
2295 if (TYPE_FN_FIELD_STUB (f, j))
2296 check_stub_method (type, i, j);
2297 v = value_fn_field (arg1p, f, j, type, offset);
2298 if (v != NULL)
2299 return v;
2300 }
2301 else
2302 while (j >= 0)
2303 {
2304 if (TYPE_FN_FIELD_STUB (f, j))
2305 check_stub_method (type, i, j);
2306 if (!typecmp (TYPE_FN_FIELD_STATIC_P (f, j),
2307 TYPE_FN_FIELD_ARGS (f, j), args))
2308 {
2309 if (TYPE_FN_FIELD_VIRTUAL_P (f, j))
2310 return value_virtual_fn_field (arg1p, f, j, type, offset);
2311 if (TYPE_FN_FIELD_STATIC_P (f, j) && static_memfuncp)
2312 *static_memfuncp = 1;
2313 v = value_fn_field (arg1p, f, j, type, offset);
2314 if (v != NULL)
2315 return v;
2316 }
2317 j--;
2318 }
2319 }
2320 }
2321
2322 for (i = TYPE_N_BASECLASSES (type) - 1; i >= 0; i--)
2323 {
2324 int base_offset;
2325
2326 if (BASETYPE_VIA_VIRTUAL (type, i))
2327 {
2328 if (TYPE_HAS_VTABLE (type))
2329 {
2330 /* HP aCC compiled type, search for virtual base offset
2331 according to HP/Taligent runtime spec. */
2332 int skip;
2333 find_rt_vbase_offset (type, TYPE_BASECLASS (type, i),
2334 VALUE_CONTENTS_ALL (*arg1p),
2335 offset + VALUE_EMBEDDED_OFFSET (*arg1p),
2336 &base_offset, &skip);
2337 if (skip >= 0)
2338 error ("Virtual base class offset not found in vtable");
2339 }
2340 else
2341 {
2342 struct type *baseclass = check_typedef (TYPE_BASECLASS (type, i));
2343 char *base_valaddr;
2344
2345 /* The virtual base class pointer might have been clobbered by the
2346 user program. Make sure that it still points to a valid memory
2347 location. */
2348
2349 if (offset < 0 || offset >= TYPE_LENGTH (type))
2350 {
2351 base_valaddr = (char *) alloca (TYPE_LENGTH (baseclass));
2352 if (target_read_memory (VALUE_ADDRESS (*arg1p)
2353 + VALUE_OFFSET (*arg1p) + offset,
2354 base_valaddr,
2355 TYPE_LENGTH (baseclass)) != 0)
2356 error ("virtual baseclass botch");
2357 }
2358 else
2359 base_valaddr = VALUE_CONTENTS (*arg1p) + offset;
2360
2361 base_offset =
2362 baseclass_offset (type, i, base_valaddr,
2363 VALUE_ADDRESS (*arg1p)
2364 + VALUE_OFFSET (*arg1p) + offset);
2365 if (base_offset == -1)
2366 error ("virtual baseclass botch");
2367 }
2368 }
2369 else
2370 {
2371 base_offset = TYPE_BASECLASS_BITPOS (type, i) / 8;
2372 }
2373 v = search_struct_method (name, arg1p, args, base_offset + offset,
2374 static_memfuncp, TYPE_BASECLASS (type, i));
2375 if (v == (struct value *) - 1)
2376 {
2377 name_matched = 1;
2378 }
2379 else if (v)
2380 {
2381 /* FIXME-bothner: Why is this commented out? Why is it here? */
2382 /* *arg1p = arg1_tmp; */
2383 return v;
2384 }
2385 }
2386 if (name_matched)
2387 return (struct value *) - 1;
2388 else
2389 return NULL;
2390 }
2391
2392 /* Given *ARGP, a value of type (pointer to a)* structure/union,
2393 extract the component named NAME from the ultimate target structure/union
2394 and return it as a value with its appropriate type.
2395 ERR is used in the error message if *ARGP's type is wrong.
2396
2397 C++: ARGS is a list of argument types to aid in the selection of
2398 an appropriate method. Also, handle derived types.
2399
2400 STATIC_MEMFUNCP, if non-NULL, points to a caller-supplied location
2401 where the truthvalue of whether the function that was resolved was
2402 a static member function or not is stored.
2403
2404 ERR is an error message to be printed in case the field is not found. */
2405
2406 struct value *
2407 value_struct_elt (struct value **argp, struct value **args,
2408 char *name, int *static_memfuncp, char *err)
2409 {
2410 register struct type *t;
2411 struct value *v;
2412
2413 COERCE_ARRAY (*argp);
2414
2415 t = check_typedef (VALUE_TYPE (*argp));
2416
2417 /* Follow pointers until we get to a non-pointer. */
2418
2419 while (TYPE_CODE (t) == TYPE_CODE_PTR || TYPE_CODE (t) == TYPE_CODE_REF)
2420 {
2421 *argp = value_ind (*argp);
2422 /* Don't coerce fn pointer to fn and then back again! */
2423 if (TYPE_CODE (VALUE_TYPE (*argp)) != TYPE_CODE_FUNC)
2424 COERCE_ARRAY (*argp);
2425 t = check_typedef (VALUE_TYPE (*argp));
2426 }
2427
2428 if (TYPE_CODE (t) == TYPE_CODE_MEMBER)
2429 error ("not implemented: member type in value_struct_elt");
2430
2431 if (TYPE_CODE (t) != TYPE_CODE_STRUCT
2432 && TYPE_CODE (t) != TYPE_CODE_UNION)
2433 error ("Attempt to extract a component of a value that is not a %s.", err);
2434
2435 /* Assume it's not, unless we see that it is. */
2436 if (static_memfuncp)
2437 *static_memfuncp = 0;
2438
2439 if (!args)
2440 {
2441 /* if there are no arguments ...do this... */
2442
2443 /* Try as a field first, because if we succeed, there
2444 is less work to be done. */
2445 v = search_struct_field (name, *argp, 0, t, 0);
2446 if (v)
2447 return v;
2448
2449 /* C++: If it was not found as a data field, then try to
2450 return it as a pointer to a method. */
2451
2452 if (destructor_name_p (name, t))
2453 error ("Cannot get value of destructor");
2454
2455 v = search_struct_method (name, argp, args, 0, static_memfuncp, t);
2456
2457 if (v == (struct value *) - 1)
2458 error ("Cannot take address of a method");
2459 else if (v == 0)
2460 {
2461 if (TYPE_NFN_FIELDS (t))
2462 error ("There is no member or method named %s.", name);
2463 else
2464 error ("There is no member named %s.", name);
2465 }
2466 return v;
2467 }
2468
2469 if (destructor_name_p (name, t))
2470 {
2471 if (!args[1])
2472 {
2473 /* Destructors are a special case. */
2474 int m_index, f_index;
2475
2476 v = NULL;
2477 if (get_destructor_fn_field (t, &m_index, &f_index))
2478 {
2479 v = value_fn_field (NULL, TYPE_FN_FIELDLIST1 (t, m_index),
2480 f_index, NULL, 0);
2481 }
2482 if (v == NULL)
2483 error ("could not find destructor function named %s.", name);
2484 else
2485 return v;
2486 }
2487 else
2488 {
2489 error ("destructor should not have any argument");
2490 }
2491 }
2492 else
2493 v = search_struct_method (name, argp, args, 0, static_memfuncp, t);
2494
2495 if (v == (struct value *) - 1)
2496 {
2497 error ("One of the arguments you tried to pass to %s could not be converted to what the function wants.", name);
2498 }
2499 else if (v == 0)
2500 {
2501 /* See if user tried to invoke data as function. If so,
2502 hand it back. If it's not callable (i.e., a pointer to function),
2503 gdb should give an error. */
2504 v = search_struct_field (name, *argp, 0, t, 0);
2505 }
2506
2507 if (!v)
2508 error ("Structure has no component named %s.", name);
2509 return v;
2510 }
2511
2512 /* Search through the methods of an object (and its bases)
2513 * to find a specified method. Return the pointer to the
2514 * fn_field list of overloaded instances.
2515 * Helper function for value_find_oload_list.
2516 * ARGP is a pointer to a pointer to a value (the object)
2517 * METHOD is a string containing the method name
2518 * OFFSET is the offset within the value
2519 * STATIC_MEMFUNCP is set if the method is static
2520 * TYPE is the assumed type of the object
2521 * NUM_FNS is the number of overloaded instances
2522 * BASETYPE is set to the actual type of the subobject where the method is found
2523 * BOFFSET is the offset of the base subobject where the method is found */
2524
2525 static struct fn_field *
2526 find_method_list (struct value **argp, char *method, int offset,
2527 struct type *type, int *num_fns,
2528 struct type **basetype, int *boffset)
2529 {
2530 int i;
2531 struct fn_field *f;
2532 CHECK_TYPEDEF (type);
2533
2534 *num_fns = 0;
2535
2536 /* First check in object itself */
2537 for (i = TYPE_NFN_FIELDS (type) - 1; i >= 0; i--)
2538 {
2539 /* pai: FIXME What about operators and type conversions? */
2540 char *fn_field_name = TYPE_FN_FIELDLIST_NAME (type, i);
2541 if (fn_field_name && (strcmp_iw (fn_field_name, method) == 0))
2542 {
2543 /* Resolve any stub methods. */
2544 int len = TYPE_FN_FIELDLIST_LENGTH (type, i);
2545 struct fn_field *f = TYPE_FN_FIELDLIST1 (type, i);
2546 int j;
2547
2548 *num_fns = len;
2549 *basetype = type;
2550 *boffset = offset;
2551
2552 for (j = 0; j < len; j++)
2553 {
2554 if (TYPE_FN_FIELD_STUB (f, j))
2555 check_stub_method (type, i, j);
2556 }
2557
2558 return f;
2559 }
2560 }
2561
2562 /* Not found in object, check in base subobjects */
2563 for (i = TYPE_N_BASECLASSES (type) - 1; i >= 0; i--)
2564 {
2565 int base_offset;
2566 if (BASETYPE_VIA_VIRTUAL (type, i))
2567 {
2568 if (TYPE_HAS_VTABLE (type))
2569 {
2570 /* HP aCC compiled type, search for virtual base offset
2571 * according to HP/Taligent runtime spec. */
2572 int skip;
2573 find_rt_vbase_offset (type, TYPE_BASECLASS (type, i),
2574 VALUE_CONTENTS_ALL (*argp),
2575 offset + VALUE_EMBEDDED_OFFSET (*argp),
2576 &base_offset, &skip);
2577 if (skip >= 0)
2578 error ("Virtual base class offset not found in vtable");
2579 }
2580 else
2581 {
2582 /* probably g++ runtime model */
2583 base_offset = VALUE_OFFSET (*argp) + offset;
2584 base_offset =
2585 baseclass_offset (type, i,
2586 VALUE_CONTENTS (*argp) + base_offset,
2587 VALUE_ADDRESS (*argp) + base_offset);
2588 if (base_offset == -1)
2589 error ("virtual baseclass botch");
2590 }
2591 }
2592 else
2593 /* non-virtual base, simply use bit position from debug info */
2594 {
2595 base_offset = TYPE_BASECLASS_BITPOS (type, i) / 8;
2596 }
2597 f = find_method_list (argp, method, base_offset + offset,
2598 TYPE_BASECLASS (type, i), num_fns, basetype,
2599 boffset);
2600 if (f)
2601 return f;
2602 }
2603 return NULL;
2604 }
2605
2606 /* Return the list of overloaded methods of a specified name.
2607 * ARGP is a pointer to a pointer to a value (the object)
2608 * METHOD is the method name
2609 * OFFSET is the offset within the value contents
2610 * STATIC_MEMFUNCP is set if the method is static
2611 * NUM_FNS is the number of overloaded instances
2612 * BASETYPE is set to the type of the base subobject that defines the method
2613 * BOFFSET is the offset of the base subobject which defines the method */
2614
2615 struct fn_field *
2616 value_find_oload_method_list (struct value **argp, char *method, int offset,
2617 int *num_fns, struct type **basetype,
2618 int *boffset)
2619 {
2620 struct type *t;
2621
2622 t = check_typedef (VALUE_TYPE (*argp));
2623
2624 /* code snarfed from value_struct_elt */
2625 while (TYPE_CODE (t) == TYPE_CODE_PTR || TYPE_CODE (t) == TYPE_CODE_REF)
2626 {
2627 *argp = value_ind (*argp);
2628 /* Don't coerce fn pointer to fn and then back again! */
2629 if (TYPE_CODE (VALUE_TYPE (*argp)) != TYPE_CODE_FUNC)
2630 COERCE_ARRAY (*argp);
2631 t = check_typedef (VALUE_TYPE (*argp));
2632 }
2633
2634 if (TYPE_CODE (t) == TYPE_CODE_MEMBER)
2635 error ("Not implemented: member type in value_find_oload_lis");
2636
2637 if (TYPE_CODE (t) != TYPE_CODE_STRUCT
2638 && TYPE_CODE (t) != TYPE_CODE_UNION)
2639 error ("Attempt to extract a component of a value that is not a struct or union");
2640
2641 return find_method_list (argp, method, 0, t, num_fns, basetype, boffset);
2642 }
2643
2644 /* Given an array of argument types (ARGTYPES) (which includes an
2645 entry for "this" in the case of C++ methods), the number of
2646 arguments NARGS, the NAME of a function whether it's a method or
2647 not (METHOD), and the degree of laxness (LAX) in conforming to
2648 overload resolution rules in ANSI C++, find the best function that
2649 matches on the argument types according to the overload resolution
2650 rules.
2651
2652 In the case of class methods, the parameter OBJ is an object value
2653 in which to search for overloaded methods.
2654
2655 In the case of non-method functions, the parameter FSYM is a symbol
2656 corresponding to one of the overloaded functions.
2657
2658 Return value is an integer: 0 -> good match, 10 -> debugger applied
2659 non-standard coercions, 100 -> incompatible.
2660
2661 If a method is being searched for, VALP will hold the value.
2662 If a non-method is being searched for, SYMP will hold the symbol for it.
2663
2664 If a method is being searched for, and it is a static method,
2665 then STATICP will point to a non-zero value.
2666
2667 Note: This function does *not* check the value of
2668 overload_resolution. Caller must check it to see whether overload
2669 resolution is permitted.
2670 */
2671
2672 int
2673 find_overload_match (struct type **arg_types, int nargs, char *name, int method,
2674 int lax, struct value **objp, struct symbol *fsym,
2675 struct value **valp, struct symbol **symp, int *staticp)
2676 {
2677 int nparms;
2678 struct type **parm_types;
2679 int champ_nparms = 0;
2680 struct value *obj = (objp ? *objp : NULL);
2681
2682 short oload_champ = -1; /* Index of best overloaded function */
2683 short oload_ambiguous = 0; /* Current ambiguity state for overload resolution */
2684 /* 0 => no ambiguity, 1 => two good funcs, 2 => incomparable funcs */
2685 short oload_ambig_champ = -1; /* 2nd contender for best match */
2686 short oload_non_standard = 0; /* did we have to use non-standard conversions? */
2687 short oload_incompatible = 0; /* are args supplied incompatible with any function? */
2688
2689 struct badness_vector *bv; /* A measure of how good an overloaded instance is */
2690 struct badness_vector *oload_champ_bv = NULL; /* The measure for the current best match */
2691
2692 struct value *temp = obj;
2693 struct fn_field *fns_ptr = NULL; /* For methods, the list of overloaded methods */
2694 struct symbol **oload_syms = NULL; /* For non-methods, the list of overloaded function symbols */
2695 int num_fns = 0; /* Number of overloaded instances being considered */
2696 struct type *basetype = NULL;
2697 int boffset;
2698 register int jj;
2699 register int ix;
2700 int static_offset;
2701
2702 char *obj_type_name = NULL;
2703 char *func_name = NULL;
2704
2705 /* Get the list of overloaded methods or functions */
2706 if (method)
2707 {
2708 obj_type_name = TYPE_NAME (VALUE_TYPE (obj));
2709 /* Hack: evaluate_subexp_standard often passes in a pointer
2710 value rather than the object itself, so try again */
2711 if ((!obj_type_name || !*obj_type_name) &&
2712 (TYPE_CODE (VALUE_TYPE (obj)) == TYPE_CODE_PTR))
2713 obj_type_name = TYPE_NAME (TYPE_TARGET_TYPE (VALUE_TYPE (obj)));
2714
2715 fns_ptr = value_find_oload_method_list (&temp, name, 0,
2716 &num_fns,
2717 &basetype, &boffset);
2718 if (!fns_ptr || !num_fns)
2719 error ("Couldn't find method %s%s%s",
2720 obj_type_name,
2721 (obj_type_name && *obj_type_name) ? "::" : "",
2722 name);
2723 /* If we are dealing with stub method types, they should have
2724 been resolved by find_method_list via value_find_oload_method_list
2725 above. */
2726 gdb_assert (TYPE_DOMAIN_TYPE (fns_ptr[0].type) != NULL);
2727 }
2728 else
2729 {
2730 int i = -1;
2731 func_name = cplus_demangle (SYMBOL_NAME (fsym), DMGL_NO_OPTS);
2732
2733 /* If the name is NULL this must be a C-style function.
2734 Just return the same symbol. */
2735 if (!func_name)
2736 {
2737 *symp = fsym;
2738 return 0;
2739 }
2740
2741 oload_syms = make_symbol_overload_list (fsym);
2742 while (oload_syms[++i])
2743 num_fns++;
2744 if (!num_fns)
2745 error ("Couldn't find function %s", func_name);
2746 }
2747
2748 oload_champ_bv = NULL;
2749
2750 /* Consider each candidate in turn */
2751 for (ix = 0; ix < num_fns; ix++)
2752 {
2753 static_offset = 0;
2754 if (method)
2755 {
2756 if (TYPE_FN_FIELD_STATIC_P (fns_ptr, ix))
2757 static_offset = 1;
2758 nparms=0;
2759
2760 if (TYPE_FN_FIELD_ARGS(fns_ptr,ix))
2761 {
2762 while (TYPE_CODE(TYPE_FN_FIELD_ARGS(fns_ptr,ix)[nparms]) != TYPE_CODE_VOID)
2763 nparms++;
2764 }
2765 }
2766 else
2767 {
2768 /* If it's not a method, this is the proper place */
2769 nparms=TYPE_NFIELDS(SYMBOL_TYPE(oload_syms[ix]));
2770 }
2771
2772 /* Prepare array of parameter types */
2773 parm_types = (struct type **) xmalloc (nparms * (sizeof (struct type *)));
2774 for (jj = 0; jj < nparms; jj++)
2775 parm_types[jj] = (method
2776 ? (TYPE_FN_FIELD_ARGS (fns_ptr, ix)[jj])
2777 : TYPE_FIELD_TYPE (SYMBOL_TYPE (oload_syms[ix]), jj));
2778
2779 /* Compare parameter types to supplied argument types. Skip THIS for
2780 static methods. */
2781 bv = rank_function (parm_types, nparms, arg_types + static_offset,
2782 nargs - static_offset);
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 - static_offset; 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 static_offset = 0;
2845 if (method && TYPE_FN_FIELD_STATIC_P (fns_ptr, oload_champ))
2846 static_offset = 1;
2847 for (ix = 1; ix <= nargs - static_offset; ix++)
2848 {
2849 if (oload_champ_bv->rank[ix] >= 100)
2850 oload_incompatible = 1; /* truly mismatched types */
2851
2852 else if (oload_champ_bv->rank[ix] >= 10)
2853 oload_non_standard = 1; /* non-standard type conversions needed */
2854 }
2855 if (oload_incompatible)
2856 {
2857 if (method)
2858 error ("Cannot resolve method %s%s%s to any overloaded instance",
2859 obj_type_name,
2860 (obj_type_name && *obj_type_name) ? "::" : "",
2861 name);
2862 else
2863 error ("Cannot resolve function %s to any overloaded instance",
2864 func_name);
2865 }
2866 else if (oload_non_standard)
2867 {
2868 if (method)
2869 warning ("Using non-standard conversion to match method %s%s%s to supplied arguments",
2870 obj_type_name,
2871 (obj_type_name && *obj_type_name) ? "::" : "",
2872 name);
2873 else
2874 warning ("Using non-standard conversion to match function %s to supplied arguments",
2875 func_name);
2876 }
2877
2878 if (method)
2879 {
2880 if (staticp && TYPE_FN_FIELD_STATIC_P (fns_ptr, oload_champ))
2881 *staticp = 1;
2882 else if (staticp)
2883 *staticp = 0;
2884 if (TYPE_FN_FIELD_VIRTUAL_P (fns_ptr, oload_champ))
2885 *valp = value_virtual_fn_field (&temp, fns_ptr, oload_champ, basetype, boffset);
2886 else
2887 *valp = value_fn_field (&temp, fns_ptr, oload_champ, basetype, boffset);
2888 }
2889 else
2890 {
2891 *symp = oload_syms[oload_champ];
2892 xfree (func_name);
2893 }
2894
2895 if (objp)
2896 {
2897 if (TYPE_CODE (VALUE_TYPE (temp)) != TYPE_CODE_PTR
2898 && TYPE_CODE (VALUE_TYPE (*objp)) == TYPE_CODE_PTR)
2899 {
2900 temp = value_addr (temp);
2901 }
2902 *objp = temp;
2903 }
2904 return oload_incompatible ? 100 : (oload_non_standard ? 10 : 0);
2905 }
2906
2907 /* C++: return 1 is NAME is a legitimate name for the destructor
2908 of type TYPE. If TYPE does not have a destructor, or
2909 if NAME is inappropriate for TYPE, an error is signaled. */
2910 int
2911 destructor_name_p (const char *name, const struct type *type)
2912 {
2913 /* destructors are a special case. */
2914
2915 if (name[0] == '~')
2916 {
2917 char *dname = type_name_no_tag (type);
2918 char *cp = strchr (dname, '<');
2919 unsigned int len;
2920
2921 /* Do not compare the template part for template classes. */
2922 if (cp == NULL)
2923 len = strlen (dname);
2924 else
2925 len = cp - dname;
2926 if (strlen (name + 1) != len || !STREQN (dname, name + 1, len))
2927 error ("name of destructor must equal name of class");
2928 else
2929 return 1;
2930 }
2931 return 0;
2932 }
2933
2934 /* Helper function for check_field: Given TYPE, a structure/union,
2935 return 1 if the component named NAME from the ultimate
2936 target structure/union is defined, otherwise, return 0. */
2937
2938 static int
2939 check_field_in (register struct type *type, const char *name)
2940 {
2941 register int i;
2942
2943 for (i = TYPE_NFIELDS (type) - 1; i >= TYPE_N_BASECLASSES (type); i--)
2944 {
2945 char *t_field_name = TYPE_FIELD_NAME (type, i);
2946 if (t_field_name && (strcmp_iw (t_field_name, name) == 0))
2947 return 1;
2948 }
2949
2950 /* C++: If it was not found as a data field, then try to
2951 return it as a pointer to a method. */
2952
2953 /* Destructors are a special case. */
2954 if (destructor_name_p (name, type))
2955 {
2956 int m_index, f_index;
2957
2958 return get_destructor_fn_field (type, &m_index, &f_index);
2959 }
2960
2961 for (i = TYPE_NFN_FIELDS (type) - 1; i >= 0; --i)
2962 {
2963 if (strcmp_iw (TYPE_FN_FIELDLIST_NAME (type, i), name) == 0)
2964 return 1;
2965 }
2966
2967 for (i = TYPE_N_BASECLASSES (type) - 1; i >= 0; i--)
2968 if (check_field_in (TYPE_BASECLASS (type, i), name))
2969 return 1;
2970
2971 return 0;
2972 }
2973
2974
2975 /* C++: Given ARG1, a value of type (pointer to a)* structure/union,
2976 return 1 if the component named NAME from the ultimate
2977 target structure/union is defined, otherwise, return 0. */
2978
2979 int
2980 check_field (struct value *arg1, const char *name)
2981 {
2982 register struct type *t;
2983
2984 COERCE_ARRAY (arg1);
2985
2986 t = VALUE_TYPE (arg1);
2987
2988 /* Follow pointers until we get to a non-pointer. */
2989
2990 for (;;)
2991 {
2992 CHECK_TYPEDEF (t);
2993 if (TYPE_CODE (t) != TYPE_CODE_PTR && TYPE_CODE (t) != TYPE_CODE_REF)
2994 break;
2995 t = TYPE_TARGET_TYPE (t);
2996 }
2997
2998 if (TYPE_CODE (t) == TYPE_CODE_MEMBER)
2999 error ("not implemented: member type in check_field");
3000
3001 if (TYPE_CODE (t) != TYPE_CODE_STRUCT
3002 && TYPE_CODE (t) != TYPE_CODE_UNION)
3003 error ("Internal error: `this' is not an aggregate");
3004
3005 return check_field_in (t, name);
3006 }
3007
3008 /* C++: Given an aggregate type CURTYPE, and a member name NAME,
3009 return the address of this member as a "pointer to member"
3010 type. If INTYPE is non-null, then it will be the type
3011 of the member we are looking for. This will help us resolve
3012 "pointers to member functions". This function is used
3013 to resolve user expressions of the form "DOMAIN::NAME". */
3014
3015 struct value *
3016 value_struct_elt_for_reference (struct type *domain, int offset,
3017 struct type *curtype, char *name,
3018 struct type *intype)
3019 {
3020 register struct type *t = curtype;
3021 register int i;
3022 struct value *v;
3023
3024 if (TYPE_CODE (t) != TYPE_CODE_STRUCT
3025 && TYPE_CODE (t) != TYPE_CODE_UNION)
3026 error ("Internal error: non-aggregate type to value_struct_elt_for_reference");
3027
3028 for (i = TYPE_NFIELDS (t) - 1; i >= TYPE_N_BASECLASSES (t); i--)
3029 {
3030 char *t_field_name = TYPE_FIELD_NAME (t, i);
3031
3032 if (t_field_name && STREQ (t_field_name, name))
3033 {
3034 if (TYPE_FIELD_STATIC (t, i))
3035 {
3036 v = value_static_field (t, i);
3037 if (v == NULL)
3038 error ("Internal error: could not find static variable %s",
3039 name);
3040 return v;
3041 }
3042 if (TYPE_FIELD_PACKED (t, i))
3043 error ("pointers to bitfield members not allowed");
3044
3045 return value_from_longest
3046 (lookup_reference_type (lookup_member_type (TYPE_FIELD_TYPE (t, i),
3047 domain)),
3048 offset + (LONGEST) (TYPE_FIELD_BITPOS (t, i) >> 3));
3049 }
3050 }
3051
3052 /* C++: If it was not found as a data field, then try to
3053 return it as a pointer to a method. */
3054
3055 /* Destructors are a special case. */
3056 if (destructor_name_p (name, t))
3057 {
3058 error ("member pointers to destructors not implemented yet");
3059 }
3060
3061 /* Perform all necessary dereferencing. */
3062 while (intype && TYPE_CODE (intype) == TYPE_CODE_PTR)
3063 intype = TYPE_TARGET_TYPE (intype);
3064
3065 for (i = TYPE_NFN_FIELDS (t) - 1; i >= 0; --i)
3066 {
3067 char *t_field_name = TYPE_FN_FIELDLIST_NAME (t, i);
3068 char dem_opname[64];
3069
3070 if (strncmp (t_field_name, "__", 2) == 0 ||
3071 strncmp (t_field_name, "op", 2) == 0 ||
3072 strncmp (t_field_name, "type", 4) == 0)
3073 {
3074 if (cplus_demangle_opname (t_field_name, dem_opname, DMGL_ANSI))
3075 t_field_name = dem_opname;
3076 else if (cplus_demangle_opname (t_field_name, dem_opname, 0))
3077 t_field_name = dem_opname;
3078 }
3079 if (t_field_name && STREQ (t_field_name, name))
3080 {
3081 int j = TYPE_FN_FIELDLIST_LENGTH (t, i);
3082 struct fn_field *f = TYPE_FN_FIELDLIST1 (t, i);
3083
3084 if (intype == 0 && j > 1)
3085 error ("non-unique member `%s' requires type instantiation", name);
3086 if (intype)
3087 {
3088 while (j--)
3089 if (TYPE_FN_FIELD_TYPE (f, j) == intype)
3090 break;
3091 if (j < 0)
3092 error ("no member function matches that type instantiation");
3093 }
3094 else
3095 j = 0;
3096
3097 if (TYPE_FN_FIELD_STUB (f, j))
3098 check_stub_method (t, i, j);
3099 if (TYPE_FN_FIELD_VIRTUAL_P (f, j))
3100 {
3101 return value_from_longest
3102 (lookup_reference_type
3103 (lookup_member_type (TYPE_FN_FIELD_TYPE (f, j),
3104 domain)),
3105 (LONGEST) METHOD_PTR_FROM_VOFFSET (TYPE_FN_FIELD_VOFFSET (f, j)));
3106 }
3107 else
3108 {
3109 struct symbol *s = lookup_symbol (TYPE_FN_FIELD_PHYSNAME (f, j),
3110 0, VAR_NAMESPACE, 0, NULL);
3111 if (s == NULL)
3112 {
3113 v = 0;
3114 }
3115 else
3116 {
3117 v = read_var_value (s, 0);
3118 #if 0
3119 VALUE_TYPE (v) = lookup_reference_type
3120 (lookup_member_type (TYPE_FN_FIELD_TYPE (f, j),
3121 domain));
3122 #endif
3123 }
3124 return v;
3125 }
3126 }
3127 }
3128 for (i = TYPE_N_BASECLASSES (t) - 1; i >= 0; i--)
3129 {
3130 struct value *v;
3131 int base_offset;
3132
3133 if (BASETYPE_VIA_VIRTUAL (t, i))
3134 base_offset = 0;
3135 else
3136 base_offset = TYPE_BASECLASS_BITPOS (t, i) / 8;
3137 v = value_struct_elt_for_reference (domain,
3138 offset + base_offset,
3139 TYPE_BASECLASS (t, i),
3140 name,
3141 intype);
3142 if (v)
3143 return v;
3144 }
3145 return 0;
3146 }
3147
3148
3149 /* Given a pointer value V, find the real (RTTI) type
3150 of the object it points to.
3151 Other parameters FULL, TOP, USING_ENC as with value_rtti_type()
3152 and refer to the values computed for the object pointed to. */
3153
3154 struct type *
3155 value_rtti_target_type (struct value *v, int *full, int *top, int *using_enc)
3156 {
3157 struct value *target;
3158
3159 target = value_ind (v);
3160
3161 return value_rtti_type (target, full, top, using_enc);
3162 }
3163
3164 /* Given a value pointed to by ARGP, check its real run-time type, and
3165 if that is different from the enclosing type, create a new value
3166 using the real run-time type as the enclosing type (and of the same
3167 type as ARGP) and return it, with the embedded offset adjusted to
3168 be the correct offset to the enclosed object
3169 RTYPE is the type, and XFULL, XTOP, and XUSING_ENC are the other
3170 parameters, computed by value_rtti_type(). If these are available,
3171 they can be supplied and a second call to value_rtti_type() is avoided.
3172 (Pass RTYPE == NULL if they're not available */
3173
3174 struct value *
3175 value_full_object (struct value *argp, struct type *rtype, int xfull, int xtop,
3176 int xusing_enc)
3177 {
3178 struct type *real_type;
3179 int full = 0;
3180 int top = -1;
3181 int using_enc = 0;
3182 struct value *new_val;
3183
3184 if (rtype)
3185 {
3186 real_type = rtype;
3187 full = xfull;
3188 top = xtop;
3189 using_enc = xusing_enc;
3190 }
3191 else
3192 real_type = value_rtti_type (argp, &full, &top, &using_enc);
3193
3194 /* If no RTTI data, or if object is already complete, do nothing */
3195 if (!real_type || real_type == VALUE_ENCLOSING_TYPE (argp))
3196 return argp;
3197
3198 /* If we have the full object, but for some reason the enclosing
3199 type is wrong, set it *//* pai: FIXME -- sounds iffy */
3200 if (full)
3201 {
3202 argp = value_change_enclosing_type (argp, real_type);
3203 return argp;
3204 }
3205
3206 /* Check if object is in memory */
3207 if (VALUE_LVAL (argp) != lval_memory)
3208 {
3209 warning ("Couldn't retrieve complete object of RTTI type %s; object may be in register(s).", TYPE_NAME (real_type));
3210
3211 return argp;
3212 }
3213
3214 /* All other cases -- retrieve the complete object */
3215 /* Go back by the computed top_offset from the beginning of the object,
3216 adjusting for the embedded offset of argp if that's what value_rtti_type
3217 used for its computation. */
3218 new_val = value_at_lazy (real_type, VALUE_ADDRESS (argp) - top +
3219 (using_enc ? 0 : VALUE_EMBEDDED_OFFSET (argp)),
3220 VALUE_BFD_SECTION (argp));
3221 VALUE_TYPE (new_val) = VALUE_TYPE (argp);
3222 VALUE_EMBEDDED_OFFSET (new_val) = using_enc ? top + VALUE_EMBEDDED_OFFSET (argp) : top;
3223 return new_val;
3224 }
3225
3226
3227
3228
3229 /* C++: return the value of the class instance variable, if one exists.
3230 Flag COMPLAIN signals an error if the request is made in an
3231 inappropriate context. */
3232
3233 struct value *
3234 value_of_this (int complain)
3235 {
3236 struct symbol *func, *sym;
3237 struct block *b;
3238 int i;
3239 static const char funny_this[] = "this";
3240 struct value *this;
3241
3242 if (selected_frame == 0)
3243 {
3244 if (complain)
3245 error ("no frame selected");
3246 else
3247 return 0;
3248 }
3249
3250 func = get_frame_function (selected_frame);
3251 if (!func)
3252 {
3253 if (complain)
3254 error ("no `this' in nameless context");
3255 else
3256 return 0;
3257 }
3258
3259 b = SYMBOL_BLOCK_VALUE (func);
3260 i = BLOCK_NSYMS (b);
3261 if (i <= 0)
3262 {
3263 if (complain)
3264 error ("no args, no `this'");
3265 else
3266 return 0;
3267 }
3268
3269 /* Calling lookup_block_symbol is necessary to get the LOC_REGISTER
3270 symbol instead of the LOC_ARG one (if both exist). */
3271 sym = lookup_block_symbol (b, funny_this, NULL, VAR_NAMESPACE);
3272 if (sym == NULL)
3273 {
3274 if (complain)
3275 error ("current stack frame not in method");
3276 else
3277 return NULL;
3278 }
3279
3280 this = read_var_value (sym, selected_frame);
3281 if (this == 0 && complain)
3282 error ("`this' argument at unknown address");
3283 return this;
3284 }
3285
3286 /* Create a slice (sub-string, sub-array) of ARRAY, that is LENGTH elements
3287 long, starting at LOWBOUND. The result has the same lower bound as
3288 the original ARRAY. */
3289
3290 struct value *
3291 value_slice (struct value *array, int lowbound, int length)
3292 {
3293 struct type *slice_range_type, *slice_type, *range_type;
3294 LONGEST lowerbound, upperbound, offset;
3295 struct value *slice;
3296 struct type *array_type;
3297 array_type = check_typedef (VALUE_TYPE (array));
3298 COERCE_VARYING_ARRAY (array, array_type);
3299 if (TYPE_CODE (array_type) != TYPE_CODE_ARRAY
3300 && TYPE_CODE (array_type) != TYPE_CODE_STRING
3301 && TYPE_CODE (array_type) != TYPE_CODE_BITSTRING)
3302 error ("cannot take slice of non-array");
3303 range_type = TYPE_INDEX_TYPE (array_type);
3304 if (get_discrete_bounds (range_type, &lowerbound, &upperbound) < 0)
3305 error ("slice from bad array or bitstring");
3306 if (lowbound < lowerbound || length < 0
3307 || lowbound + length - 1 > upperbound
3308 /* Chill allows zero-length strings but not arrays. */
3309 || (current_language->la_language == language_chill
3310 && length == 0 && TYPE_CODE (array_type) == TYPE_CODE_ARRAY))
3311 error ("slice out of range");
3312 /* FIXME-type-allocation: need a way to free this type when we are
3313 done with it. */
3314 slice_range_type = create_range_type ((struct type *) NULL,
3315 TYPE_TARGET_TYPE (range_type),
3316 lowbound, lowbound + length - 1);
3317 if (TYPE_CODE (array_type) == TYPE_CODE_BITSTRING)
3318 {
3319 int i;
3320 slice_type = create_set_type ((struct type *) NULL, slice_range_type);
3321 TYPE_CODE (slice_type) = TYPE_CODE_BITSTRING;
3322 slice = value_zero (slice_type, not_lval);
3323 for (i = 0; i < length; i++)
3324 {
3325 int element = value_bit_index (array_type,
3326 VALUE_CONTENTS (array),
3327 lowbound + i);
3328 if (element < 0)
3329 error ("internal error accessing bitstring");
3330 else if (element > 0)
3331 {
3332 int j = i % TARGET_CHAR_BIT;
3333 if (BITS_BIG_ENDIAN)
3334 j = TARGET_CHAR_BIT - 1 - j;
3335 VALUE_CONTENTS_RAW (slice)[i / TARGET_CHAR_BIT] |= (1 << j);
3336 }
3337 }
3338 /* We should set the address, bitssize, and bitspos, so the clice
3339 can be used on the LHS, but that may require extensions to
3340 value_assign. For now, just leave as a non_lval. FIXME. */
3341 }
3342 else
3343 {
3344 struct type *element_type = TYPE_TARGET_TYPE (array_type);
3345 offset
3346 = (lowbound - lowerbound) * TYPE_LENGTH (check_typedef (element_type));
3347 slice_type = create_array_type ((struct type *) NULL, element_type,
3348 slice_range_type);
3349 TYPE_CODE (slice_type) = TYPE_CODE (array_type);
3350 slice = allocate_value (slice_type);
3351 if (VALUE_LAZY (array))
3352 VALUE_LAZY (slice) = 1;
3353 else
3354 memcpy (VALUE_CONTENTS (slice), VALUE_CONTENTS (array) + offset,
3355 TYPE_LENGTH (slice_type));
3356 if (VALUE_LVAL (array) == lval_internalvar)
3357 VALUE_LVAL (slice) = lval_internalvar_component;
3358 else
3359 VALUE_LVAL (slice) = VALUE_LVAL (array);
3360 VALUE_ADDRESS (slice) = VALUE_ADDRESS (array);
3361 VALUE_OFFSET (slice) = VALUE_OFFSET (array) + offset;
3362 }
3363 return slice;
3364 }
3365
3366 /* Assuming chill_varying_type (VARRAY) is true, return an equivalent
3367 value as a fixed-length array. */
3368
3369 struct value *
3370 varying_to_slice (struct value *varray)
3371 {
3372 struct type *vtype = check_typedef (VALUE_TYPE (varray));
3373 LONGEST length = unpack_long (TYPE_FIELD_TYPE (vtype, 0),
3374 VALUE_CONTENTS (varray)
3375 + TYPE_FIELD_BITPOS (vtype, 0) / 8);
3376 return value_slice (value_primitive_field (varray, 0, 1, vtype), 0, length);
3377 }
3378
3379 /* Create a value for a FORTRAN complex number. Currently most of
3380 the time values are coerced to COMPLEX*16 (i.e. a complex number
3381 composed of 2 doubles. This really should be a smarter routine
3382 that figures out precision inteligently as opposed to assuming
3383 doubles. FIXME: fmb */
3384
3385 struct value *
3386 value_literal_complex (struct value *arg1, struct value *arg2, struct type *type)
3387 {
3388 struct value *val;
3389 struct type *real_type = TYPE_TARGET_TYPE (type);
3390
3391 val = allocate_value (type);
3392 arg1 = value_cast (real_type, arg1);
3393 arg2 = value_cast (real_type, arg2);
3394
3395 memcpy (VALUE_CONTENTS_RAW (val),
3396 VALUE_CONTENTS (arg1), TYPE_LENGTH (real_type));
3397 memcpy (VALUE_CONTENTS_RAW (val) + TYPE_LENGTH (real_type),
3398 VALUE_CONTENTS (arg2), TYPE_LENGTH (real_type));
3399 return val;
3400 }
3401
3402 /* Cast a value into the appropriate complex data type. */
3403
3404 static struct value *
3405 cast_into_complex (struct type *type, struct value *val)
3406 {
3407 struct type *real_type = TYPE_TARGET_TYPE (type);
3408 if (TYPE_CODE (VALUE_TYPE (val)) == TYPE_CODE_COMPLEX)
3409 {
3410 struct type *val_real_type = TYPE_TARGET_TYPE (VALUE_TYPE (val));
3411 struct value *re_val = allocate_value (val_real_type);
3412 struct value *im_val = allocate_value (val_real_type);
3413
3414 memcpy (VALUE_CONTENTS_RAW (re_val),
3415 VALUE_CONTENTS (val), TYPE_LENGTH (val_real_type));
3416 memcpy (VALUE_CONTENTS_RAW (im_val),
3417 VALUE_CONTENTS (val) + TYPE_LENGTH (val_real_type),
3418 TYPE_LENGTH (val_real_type));
3419
3420 return value_literal_complex (re_val, im_val, type);
3421 }
3422 else if (TYPE_CODE (VALUE_TYPE (val)) == TYPE_CODE_FLT
3423 || TYPE_CODE (VALUE_TYPE (val)) == TYPE_CODE_INT)
3424 return value_literal_complex (val, value_zero (real_type, not_lval), type);
3425 else
3426 error ("cannot cast non-number to complex");
3427 }
3428
3429 void
3430 _initialize_valops (void)
3431 {
3432 #if 0
3433 add_show_from_set
3434 (add_set_cmd ("abandon", class_support, var_boolean, (char *) &auto_abandon,
3435 "Set automatic abandonment of expressions upon failure.",
3436 &setlist),
3437 &showlist);
3438 #endif
3439
3440 add_show_from_set
3441 (add_set_cmd ("overload-resolution", class_support, var_boolean, (char *) &overload_resolution,
3442 "Set overload resolution in evaluating C++ functions.",
3443 &setlist),
3444 &showlist);
3445 overload_resolution = 1;
3446
3447 add_show_from_set (
3448 add_set_cmd ("unwindonsignal", no_class, var_boolean,
3449 (char *) &unwind_on_signal_p,
3450 "Set unwinding of stack if a signal is received while in a call dummy.\n\
3451 The unwindonsignal lets the user determine what gdb should do if a signal\n\
3452 is received while in a function called from gdb (call dummy). If set, gdb\n\
3453 unwinds the stack and restore the context to what as it was before the call.\n\
3454 The default is to stop in the frame where the signal was received.", &setlist),
3455 &showlist);
3456 }
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