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