2003-01-27 Andrew Cagney <ac131313@redhat.com>
[deliverable/binutils-gdb.git] / gdb / valops.c
1 /* Perform non-arithmetic operations on values, for GDB.
2 Copyright 1986, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994,
3 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003
4 Free Software Foundation, Inc.
5
6 This file is part of GDB.
7
8 This program is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 2 of the License, or
11 (at your option) any later version.
12
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
17
18 You should have received a copy of the GNU General Public License
19 along with this program; if not, write to the Free Software
20 Foundation, Inc., 59 Temple Place - Suite 330,
21 Boston, MA 02111-1307, USA. */
22
23 #include "defs.h"
24 #include "symtab.h"
25 #include "gdbtypes.h"
26 #include "value.h"
27 #include "frame.h"
28 #include "inferior.h"
29 #include "gdbcore.h"
30 #include "target.h"
31 #include "demangle.h"
32 #include "language.h"
33 #include "gdbcmd.h"
34 #include "regcache.h"
35 #include "cp-abi.h"
36
37 #include <errno.h>
38 #include "gdb_string.h"
39 #include "gdb_assert.h"
40
41 /* Flag indicating HP compilers were used; needed to correctly handle some
42 value operations with HP aCC code/runtime. */
43 extern int hp_som_som_object_present;
44
45 extern int overload_debug;
46 /* Local functions. */
47
48 static int typecmp (int staticp, int varargs, int nargs,
49 struct field t1[], struct value *t2[]);
50
51 static CORE_ADDR find_function_addr (struct value *, struct type **);
52 static struct value *value_arg_coerce (struct value *, struct type *, int);
53
54
55 static CORE_ADDR value_push (CORE_ADDR, struct value *);
56
57 static struct value *search_struct_field (char *, struct value *, int,
58 struct type *, int);
59
60 static struct value *search_struct_method (char *, struct value **,
61 struct value **,
62 int, int *, struct type *);
63
64 static int check_field_in (struct type *, const char *);
65
66 static CORE_ADDR allocate_space_in_inferior (int);
67
68 static struct value *cast_into_complex (struct type *, struct value *);
69
70 static struct fn_field *find_method_list (struct value ** argp, char *method,
71 int offset,
72 struct type *type, int *num_fns,
73 struct type **basetype,
74 int *boffset);
75
76 void _initialize_valops (void);
77
78 /* Flag for whether we want to abandon failed expression evals by default. */
79
80 #if 0
81 static int auto_abandon = 0;
82 #endif
83
84 int overload_resolution = 0;
85
86 /* This boolean tells what gdb should do if a signal is received while in
87 a function called from gdb (call dummy). If set, gdb unwinds the stack
88 and restore the context to what as it was before the call.
89 The default is to stop in the frame where the signal was received. */
90
91 int unwind_on_signal_p = 0;
92
93 /* How you should pass arguments to a function depends on whether it
94 was defined in K&R style or prototype style. If you define a
95 function using the K&R syntax that takes a `float' argument, then
96 callers must pass that argument as a `double'. If you define the
97 function using the prototype syntax, then you must pass the
98 argument as a `float', with no promotion.
99
100 Unfortunately, on certain older platforms, the debug info doesn't
101 indicate reliably how each function was defined. A function type's
102 TYPE_FLAG_PROTOTYPED flag may be clear, even if the function was
103 defined in prototype style. When calling a function whose
104 TYPE_FLAG_PROTOTYPED flag is clear, GDB consults this flag to decide
105 what to do.
106
107 For modern targets, it is proper to assume that, if the prototype
108 flag is clear, that can be trusted: `float' arguments should be
109 promoted to `double'. For some older targets, if the prototype
110 flag is clear, that doesn't tell us anything. The default is to
111 trust the debug information; the user can override this behavior
112 with "set coerce-float-to-double 0". */
113
114 static int coerce_float_to_double;
115 \f
116
117 /* Find the address of function name NAME in the inferior. */
118
119 struct value *
120 find_function_in_inferior (const char *name)
121 {
122 register struct symbol *sym;
123 sym = lookup_symbol (name, 0, VAR_NAMESPACE, 0, NULL);
124 if (sym != NULL)
125 {
126 if (SYMBOL_CLASS (sym) != LOC_BLOCK)
127 {
128 error ("\"%s\" exists in this program but is not a function.",
129 name);
130 }
131 return value_of_variable (sym, NULL);
132 }
133 else
134 {
135 struct minimal_symbol *msymbol = lookup_minimal_symbol (name, NULL, NULL);
136 if (msymbol != NULL)
137 {
138 struct type *type;
139 CORE_ADDR maddr;
140 type = lookup_pointer_type (builtin_type_char);
141 type = lookup_function_type (type);
142 type = lookup_pointer_type (type);
143 maddr = SYMBOL_VALUE_ADDRESS (msymbol);
144 return value_from_pointer (type, maddr);
145 }
146 else
147 {
148 if (!target_has_execution)
149 error ("evaluation of this expression requires the target program to be active");
150 else
151 error ("evaluation of this expression requires the program to have a function \"%s\".", name);
152 }
153 }
154 }
155
156 /* Allocate NBYTES of space in the inferior using the inferior's malloc
157 and return a value that is a pointer to the allocated space. */
158
159 struct value *
160 value_allocate_space_in_inferior (int len)
161 {
162 struct value *blocklen;
163 struct value *val = find_function_in_inferior (NAME_OF_MALLOC);
164
165 blocklen = value_from_longest (builtin_type_int, (LONGEST) len);
166 val = call_function_by_hand (val, 1, &blocklen);
167 if (value_logical_not (val))
168 {
169 if (!target_has_execution)
170 error ("No memory available to program now: you need to start the target first");
171 else
172 error ("No memory available to program: call to malloc failed");
173 }
174 return val;
175 }
176
177 static CORE_ADDR
178 allocate_space_in_inferior (int len)
179 {
180 return value_as_long (value_allocate_space_in_inferior (len));
181 }
182
183 /* Cast value ARG2 to type TYPE and return as a value.
184 More general than a C cast: accepts any two types of the same length,
185 and if ARG2 is an lvalue it can be cast into anything at all. */
186 /* In C++, casts may change pointer or object representations. */
187
188 struct value *
189 value_cast (struct type *type, struct value *arg2)
190 {
191 register enum type_code code1;
192 register enum type_code code2;
193 register int scalar;
194 struct type *type2;
195
196 int convert_to_boolean = 0;
197
198 if (VALUE_TYPE (arg2) == type)
199 return arg2;
200
201 CHECK_TYPEDEF (type);
202 code1 = TYPE_CODE (type);
203 COERCE_REF (arg2);
204 type2 = check_typedef (VALUE_TYPE (arg2));
205
206 /* A cast to an undetermined-length array_type, such as (TYPE [])OBJECT,
207 is treated like a cast to (TYPE [N])OBJECT,
208 where N is sizeof(OBJECT)/sizeof(TYPE). */
209 if (code1 == TYPE_CODE_ARRAY)
210 {
211 struct type *element_type = TYPE_TARGET_TYPE (type);
212 unsigned element_length = TYPE_LENGTH (check_typedef (element_type));
213 if (element_length > 0
214 && TYPE_ARRAY_UPPER_BOUND_TYPE (type) == BOUND_CANNOT_BE_DETERMINED)
215 {
216 struct type *range_type = TYPE_INDEX_TYPE (type);
217 int val_length = TYPE_LENGTH (type2);
218 LONGEST low_bound, high_bound, new_length;
219 if (get_discrete_bounds (range_type, &low_bound, &high_bound) < 0)
220 low_bound = 0, high_bound = 0;
221 new_length = val_length / element_length;
222 if (val_length % element_length != 0)
223 warning ("array element type size does not divide object size in cast");
224 /* FIXME-type-allocation: need a way to free this type when we are
225 done with it. */
226 range_type = create_range_type ((struct type *) NULL,
227 TYPE_TARGET_TYPE (range_type),
228 low_bound,
229 new_length + low_bound - 1);
230 VALUE_TYPE (arg2) = create_array_type ((struct type *) NULL,
231 element_type, range_type);
232 return arg2;
233 }
234 }
235
236 if (current_language->c_style_arrays
237 && TYPE_CODE (type2) == TYPE_CODE_ARRAY)
238 arg2 = value_coerce_array (arg2);
239
240 if (TYPE_CODE (type2) == TYPE_CODE_FUNC)
241 arg2 = value_coerce_function (arg2);
242
243 type2 = check_typedef (VALUE_TYPE (arg2));
244 COERCE_VARYING_ARRAY (arg2, type2);
245 code2 = TYPE_CODE (type2);
246
247 if (code1 == TYPE_CODE_COMPLEX)
248 return cast_into_complex (type, arg2);
249 if (code1 == TYPE_CODE_BOOL)
250 {
251 code1 = TYPE_CODE_INT;
252 convert_to_boolean = 1;
253 }
254 if (code1 == TYPE_CODE_CHAR)
255 code1 = TYPE_CODE_INT;
256 if (code2 == TYPE_CODE_BOOL || code2 == TYPE_CODE_CHAR)
257 code2 = TYPE_CODE_INT;
258
259 scalar = (code2 == TYPE_CODE_INT || code2 == TYPE_CODE_FLT
260 || code2 == TYPE_CODE_ENUM || code2 == TYPE_CODE_RANGE);
261
262 if (code1 == TYPE_CODE_STRUCT
263 && code2 == TYPE_CODE_STRUCT
264 && TYPE_NAME (type) != 0)
265 {
266 /* Look in the type of the source to see if it contains the
267 type of the target as a superclass. If so, we'll need to
268 offset the object in addition to changing its type. */
269 struct value *v = search_struct_field (type_name_no_tag (type),
270 arg2, 0, type2, 1);
271 if (v)
272 {
273 VALUE_TYPE (v) = type;
274 return v;
275 }
276 }
277 if (code1 == TYPE_CODE_FLT && scalar)
278 return value_from_double (type, value_as_double (arg2));
279 else if ((code1 == TYPE_CODE_INT || code1 == TYPE_CODE_ENUM
280 || code1 == TYPE_CODE_RANGE)
281 && (scalar || code2 == TYPE_CODE_PTR))
282 {
283 LONGEST longest;
284
285 if (hp_som_som_object_present && /* if target compiled by HP aCC */
286 (code2 == TYPE_CODE_PTR))
287 {
288 unsigned int *ptr;
289 struct value *retvalp;
290
291 switch (TYPE_CODE (TYPE_TARGET_TYPE (type2)))
292 {
293 /* With HP aCC, pointers to data members have a bias */
294 case TYPE_CODE_MEMBER:
295 retvalp = value_from_longest (type, value_as_long (arg2));
296 /* force evaluation */
297 ptr = (unsigned int *) VALUE_CONTENTS (retvalp);
298 *ptr &= ~0x20000000; /* zap 29th bit to remove bias */
299 return retvalp;
300
301 /* While pointers to methods don't really point to a function */
302 case TYPE_CODE_METHOD:
303 error ("Pointers to methods not supported with HP aCC");
304
305 default:
306 break; /* fall out and go to normal handling */
307 }
308 }
309
310 /* When we cast pointers to integers, we mustn't use
311 POINTER_TO_ADDRESS to find the address the pointer
312 represents, as value_as_long would. GDB should evaluate
313 expressions just as the compiler would --- and the compiler
314 sees a cast as a simple reinterpretation of the pointer's
315 bits. */
316 if (code2 == TYPE_CODE_PTR)
317 longest = extract_unsigned_integer (VALUE_CONTENTS (arg2),
318 TYPE_LENGTH (type2));
319 else
320 longest = value_as_long (arg2);
321 return value_from_longest (type, convert_to_boolean ?
322 (LONGEST) (longest ? 1 : 0) : longest);
323 }
324 else if (code1 == TYPE_CODE_PTR && (code2 == TYPE_CODE_INT ||
325 code2 == TYPE_CODE_ENUM ||
326 code2 == TYPE_CODE_RANGE))
327 {
328 /* TYPE_LENGTH (type) is the length of a pointer, but we really
329 want the length of an address! -- we are really dealing with
330 addresses (i.e., gdb representations) not pointers (i.e.,
331 target representations) here.
332
333 This allows things like "print *(int *)0x01000234" to work
334 without printing a misleading message -- which would
335 otherwise occur when dealing with a target having two byte
336 pointers and four byte addresses. */
337
338 int addr_bit = TARGET_ADDR_BIT;
339
340 LONGEST longest = value_as_long (arg2);
341 if (addr_bit < sizeof (LONGEST) * HOST_CHAR_BIT)
342 {
343 if (longest >= ((LONGEST) 1 << addr_bit)
344 || longest <= -((LONGEST) 1 << addr_bit))
345 warning ("value truncated");
346 }
347 return value_from_longest (type, longest);
348 }
349 else if (TYPE_LENGTH (type) == TYPE_LENGTH (type2))
350 {
351 if (code1 == TYPE_CODE_PTR && code2 == TYPE_CODE_PTR)
352 {
353 struct type *t1 = check_typedef (TYPE_TARGET_TYPE (type));
354 struct type *t2 = check_typedef (TYPE_TARGET_TYPE (type2));
355 if (TYPE_CODE (t1) == TYPE_CODE_STRUCT
356 && TYPE_CODE (t2) == TYPE_CODE_STRUCT
357 && !value_logical_not (arg2))
358 {
359 struct value *v;
360
361 /* Look in the type of the source to see if it contains the
362 type of the target as a superclass. If so, we'll need to
363 offset the pointer rather than just change its type. */
364 if (TYPE_NAME (t1) != NULL)
365 {
366 v = search_struct_field (type_name_no_tag (t1),
367 value_ind (arg2), 0, t2, 1);
368 if (v)
369 {
370 v = value_addr (v);
371 VALUE_TYPE (v) = type;
372 return v;
373 }
374 }
375
376 /* Look in the type of the target to see if it contains the
377 type of the source as a superclass. If so, we'll need to
378 offset the pointer rather than just change its type.
379 FIXME: This fails silently with virtual inheritance. */
380 if (TYPE_NAME (t2) != NULL)
381 {
382 v = search_struct_field (type_name_no_tag (t2),
383 value_zero (t1, not_lval), 0, t1, 1);
384 if (v)
385 {
386 CORE_ADDR addr2 = value_as_address (arg2);
387 addr2 -= (VALUE_ADDRESS (v)
388 + VALUE_OFFSET (v)
389 + VALUE_EMBEDDED_OFFSET (v));
390 return value_from_pointer (type, addr2);
391 }
392 }
393 }
394 /* No superclass found, just fall through to change ptr type. */
395 }
396 VALUE_TYPE (arg2) = type;
397 arg2 = value_change_enclosing_type (arg2, type);
398 VALUE_POINTED_TO_OFFSET (arg2) = 0; /* pai: chk_val */
399 return arg2;
400 }
401 else if (VALUE_LVAL (arg2) == lval_memory)
402 {
403 return value_at_lazy (type, VALUE_ADDRESS (arg2) + VALUE_OFFSET (arg2),
404 VALUE_BFD_SECTION (arg2));
405 }
406 else if (code1 == TYPE_CODE_VOID)
407 {
408 return value_zero (builtin_type_void, not_lval);
409 }
410 else
411 {
412 error ("Invalid cast.");
413 return 0;
414 }
415 }
416
417 /* Create a value of type TYPE that is zero, and return it. */
418
419 struct value *
420 value_zero (struct type *type, enum lval_type lv)
421 {
422 struct value *val = allocate_value (type);
423
424 memset (VALUE_CONTENTS (val), 0, TYPE_LENGTH (check_typedef (type)));
425 VALUE_LVAL (val) = lv;
426
427 return val;
428 }
429
430 /* Return a value with type TYPE located at ADDR.
431
432 Call value_at only if the data needs to be fetched immediately;
433 if we can be 'lazy' and defer the fetch, perhaps indefinately, call
434 value_at_lazy instead. value_at_lazy simply records the address of
435 the data and sets the lazy-evaluation-required flag. The lazy flag
436 is tested in the VALUE_CONTENTS macro, which is used if and when
437 the contents are actually required.
438
439 Note: value_at does *NOT* handle embedded offsets; perform such
440 adjustments before or after calling it. */
441
442 struct value *
443 value_at (struct type *type, CORE_ADDR addr, asection *sect)
444 {
445 struct value *val;
446
447 if (TYPE_CODE (check_typedef (type)) == TYPE_CODE_VOID)
448 error ("Attempt to dereference a generic pointer.");
449
450 val = allocate_value (type);
451
452 read_memory (addr, VALUE_CONTENTS_ALL_RAW (val), TYPE_LENGTH (type));
453
454 VALUE_LVAL (val) = lval_memory;
455 VALUE_ADDRESS (val) = addr;
456 VALUE_BFD_SECTION (val) = sect;
457
458 return val;
459 }
460
461 /* Return a lazy value with type TYPE located at ADDR (cf. value_at). */
462
463 struct value *
464 value_at_lazy (struct type *type, CORE_ADDR addr, asection *sect)
465 {
466 struct value *val;
467
468 if (TYPE_CODE (check_typedef (type)) == TYPE_CODE_VOID)
469 error ("Attempt to dereference a generic pointer.");
470
471 val = allocate_value (type);
472
473 VALUE_LVAL (val) = lval_memory;
474 VALUE_ADDRESS (val) = addr;
475 VALUE_LAZY (val) = 1;
476 VALUE_BFD_SECTION (val) = sect;
477
478 return val;
479 }
480
481 /* Called only from the VALUE_CONTENTS and VALUE_CONTENTS_ALL macros,
482 if the current data for a variable needs to be loaded into
483 VALUE_CONTENTS(VAL). Fetches the data from the user's process, and
484 clears the lazy flag to indicate that the data in the buffer is valid.
485
486 If the value is zero-length, we avoid calling read_memory, which would
487 abort. We mark the value as fetched anyway -- all 0 bytes of it.
488
489 This function returns a value because it is used in the VALUE_CONTENTS
490 macro as part of an expression, where a void would not work. The
491 value is ignored. */
492
493 int
494 value_fetch_lazy (struct value *val)
495 {
496 CORE_ADDR addr = VALUE_ADDRESS (val) + VALUE_OFFSET (val);
497 int length = TYPE_LENGTH (VALUE_ENCLOSING_TYPE (val));
498
499 struct type *type = VALUE_TYPE (val);
500 if (length)
501 read_memory (addr, VALUE_CONTENTS_ALL_RAW (val), length);
502
503 VALUE_LAZY (val) = 0;
504 return 0;
505 }
506
507
508 /* Store the contents of FROMVAL into the location of TOVAL.
509 Return a new value with the location of TOVAL and contents of FROMVAL. */
510
511 struct value *
512 value_assign (struct value *toval, struct value *fromval)
513 {
514 register struct type *type;
515 struct value *val;
516 char *raw_buffer = (char*) alloca (MAX_REGISTER_RAW_SIZE);
517 int use_buffer = 0;
518
519 if (!toval->modifiable)
520 error ("Left operand of assignment is not a modifiable lvalue.");
521
522 COERCE_REF (toval);
523
524 type = VALUE_TYPE (toval);
525 if (VALUE_LVAL (toval) != lval_internalvar)
526 fromval = value_cast (type, fromval);
527 else
528 COERCE_ARRAY (fromval);
529 CHECK_TYPEDEF (type);
530
531 /* If TOVAL is a special machine register requiring conversion
532 of program values to a special raw format,
533 convert FROMVAL's contents now, with result in `raw_buffer',
534 and set USE_BUFFER to the number of bytes to write. */
535
536 if (VALUE_REGNO (toval) >= 0)
537 {
538 int regno = VALUE_REGNO (toval);
539 if (CONVERT_REGISTER_P (regno))
540 {
541 struct type *fromtype = check_typedef (VALUE_TYPE (fromval));
542 VALUE_TO_REGISTER (fromtype, regno, VALUE_CONTENTS (fromval), raw_buffer);
543 use_buffer = REGISTER_RAW_SIZE (regno);
544 }
545 }
546
547 switch (VALUE_LVAL (toval))
548 {
549 case lval_internalvar:
550 set_internalvar (VALUE_INTERNALVAR (toval), fromval);
551 val = value_copy (VALUE_INTERNALVAR (toval)->value);
552 val = value_change_enclosing_type (val, VALUE_ENCLOSING_TYPE (fromval));
553 VALUE_EMBEDDED_OFFSET (val) = VALUE_EMBEDDED_OFFSET (fromval);
554 VALUE_POINTED_TO_OFFSET (val) = VALUE_POINTED_TO_OFFSET (fromval);
555 return val;
556
557 case lval_internalvar_component:
558 set_internalvar_component (VALUE_INTERNALVAR (toval),
559 VALUE_OFFSET (toval),
560 VALUE_BITPOS (toval),
561 VALUE_BITSIZE (toval),
562 fromval);
563 break;
564
565 case lval_memory:
566 {
567 char *dest_buffer;
568 CORE_ADDR changed_addr;
569 int changed_len;
570
571 if (VALUE_BITSIZE (toval))
572 {
573 char buffer[sizeof (LONGEST)];
574 /* We assume that the argument to read_memory is in units of
575 host chars. FIXME: Is that correct? */
576 changed_len = (VALUE_BITPOS (toval)
577 + VALUE_BITSIZE (toval)
578 + HOST_CHAR_BIT - 1)
579 / HOST_CHAR_BIT;
580
581 if (changed_len > (int) sizeof (LONGEST))
582 error ("Can't handle bitfields which don't fit in a %d bit word.",
583 (int) sizeof (LONGEST) * HOST_CHAR_BIT);
584
585 read_memory (VALUE_ADDRESS (toval) + VALUE_OFFSET (toval),
586 buffer, changed_len);
587 modify_field (buffer, value_as_long (fromval),
588 VALUE_BITPOS (toval), VALUE_BITSIZE (toval));
589 changed_addr = VALUE_ADDRESS (toval) + VALUE_OFFSET (toval);
590 dest_buffer = buffer;
591 }
592 else if (use_buffer)
593 {
594 changed_addr = VALUE_ADDRESS (toval) + VALUE_OFFSET (toval);
595 changed_len = use_buffer;
596 dest_buffer = raw_buffer;
597 }
598 else
599 {
600 changed_addr = VALUE_ADDRESS (toval) + VALUE_OFFSET (toval);
601 changed_len = TYPE_LENGTH (type);
602 dest_buffer = VALUE_CONTENTS (fromval);
603 }
604
605 write_memory (changed_addr, dest_buffer, changed_len);
606 if (memory_changed_hook)
607 memory_changed_hook (changed_addr, changed_len);
608 target_changed_event ();
609 }
610 break;
611
612 case lval_reg_frame_relative:
613 case lval_register:
614 {
615 struct frame_id old_frame;
616 /* value is stored in a series of registers in the frame
617 specified by the structure. Copy that value out, modify
618 it, and copy it back in. */
619 int amount_copied;
620 int amount_to_copy;
621 char *buffer;
622 int value_reg;
623 int reg_offset;
624 int byte_offset;
625 int regno;
626 struct frame_info *frame;
627
628 /* Since modifying a register can trash the frame chain, we
629 save the old frame and then restore the new frame
630 afterwards. */
631 old_frame = get_frame_id (deprecated_selected_frame);
632
633 /* Figure out which frame this is in currently. */
634 if (VALUE_LVAL (toval) == lval_register)
635 {
636 frame = get_current_frame ();
637 value_reg = VALUE_REGNO (toval);
638 }
639 else
640 {
641 for (frame = get_current_frame ();
642 frame && get_frame_base (frame) != VALUE_FRAME (toval);
643 frame = get_prev_frame (frame))
644 ;
645 value_reg = VALUE_FRAME_REGNUM (toval);
646 }
647
648 if (!frame)
649 error ("Value being assigned to is no longer active.");
650
651 /* Locate the first register that falls in the value that
652 needs to be transfered. Compute the offset of the value in
653 that register. */
654 {
655 int offset;
656 for (reg_offset = value_reg, offset = 0;
657 offset + REGISTER_RAW_SIZE (reg_offset) <= VALUE_OFFSET (toval);
658 reg_offset++);
659 byte_offset = VALUE_OFFSET (toval) - offset;
660 }
661
662 /* Compute the number of register aligned values that need to
663 be copied. */
664 if (VALUE_BITSIZE (toval))
665 amount_to_copy = byte_offset + 1;
666 else
667 amount_to_copy = byte_offset + TYPE_LENGTH (type);
668
669 /* And a bounce buffer. Be slightly over generous. */
670 buffer = (char *) alloca (amount_to_copy
671 + MAX_REGISTER_RAW_SIZE);
672
673 /* Copy it in. */
674 for (regno = reg_offset, amount_copied = 0;
675 amount_copied < amount_to_copy;
676 amount_copied += REGISTER_RAW_SIZE (regno), regno++)
677 {
678 frame_register_read (frame, regno, buffer + amount_copied);
679 }
680
681 /* Modify what needs to be modified. */
682 if (VALUE_BITSIZE (toval))
683 {
684 modify_field (buffer + byte_offset,
685 value_as_long (fromval),
686 VALUE_BITPOS (toval), VALUE_BITSIZE (toval));
687 }
688 else if (use_buffer)
689 {
690 memcpy (buffer + VALUE_OFFSET (toval), raw_buffer, use_buffer);
691 }
692 else
693 {
694 memcpy (buffer + byte_offset, VALUE_CONTENTS (fromval),
695 TYPE_LENGTH (type));
696 /* Do any conversion necessary when storing this type to
697 more than one register. */
698 #ifdef REGISTER_CONVERT_FROM_TYPE
699 REGISTER_CONVERT_FROM_TYPE (value_reg, type,
700 (buffer + byte_offset));
701 #endif
702 }
703
704 /* Copy it out. */
705 for (regno = reg_offset, amount_copied = 0;
706 amount_copied < amount_to_copy;
707 amount_copied += REGISTER_RAW_SIZE (regno), regno++)
708 {
709 enum lval_type lval;
710 CORE_ADDR addr;
711 int optim;
712 int realnum;
713
714 /* Just find out where to put it. */
715 frame_register (frame, regno, &optim, &lval, &addr, &realnum,
716 NULL);
717
718 if (optim)
719 error ("Attempt to assign to a value that was optimized out.");
720 if (lval == lval_memory)
721 write_memory (addr, buffer + amount_copied,
722 REGISTER_RAW_SIZE (regno));
723 else if (lval == lval_register)
724 regcache_cooked_write (current_regcache, realnum,
725 (buffer + amount_copied));
726 else
727 error ("Attempt to assign to an unmodifiable value.");
728 }
729
730 if (register_changed_hook)
731 register_changed_hook (-1);
732 target_changed_event ();
733
734 /* Assigning to the stack pointer, frame pointer, and other
735 (architecture and calling convention specific) registers
736 may cause the frame cache to be out of date. We just do
737 this on all assignments to registers for simplicity; I
738 doubt the slowdown matters. */
739 reinit_frame_cache ();
740
741 /* Having destoroyed the frame cache, restore the selected
742 frame. */
743 /* FIXME: cagney/2002-11-02: There has to be a better way of
744 doing this. Instead of constantly saving/restoring the
745 frame. Why not create a get_selected_frame() function
746 that, having saved the selected frame's ID can
747 automatically re-find the previously selected frame
748 automatically. */
749 {
750 struct frame_info *fi = frame_find_by_id (old_frame);
751 if (fi != NULL)
752 select_frame (fi);
753 }
754 }
755 break;
756
757
758 default:
759 error ("Left operand of assignment is not an lvalue.");
760 }
761
762 /* If the field does not entirely fill a LONGEST, then zero the sign bits.
763 If the field is signed, and is negative, then sign extend. */
764 if ((VALUE_BITSIZE (toval) > 0)
765 && (VALUE_BITSIZE (toval) < 8 * (int) sizeof (LONGEST)))
766 {
767 LONGEST fieldval = value_as_long (fromval);
768 LONGEST valmask = (((ULONGEST) 1) << VALUE_BITSIZE (toval)) - 1;
769
770 fieldval &= valmask;
771 if (!TYPE_UNSIGNED (type) && (fieldval & (valmask ^ (valmask >> 1))))
772 fieldval |= ~valmask;
773
774 fromval = value_from_longest (type, fieldval);
775 }
776
777 val = value_copy (toval);
778 memcpy (VALUE_CONTENTS_RAW (val), VALUE_CONTENTS (fromval),
779 TYPE_LENGTH (type));
780 VALUE_TYPE (val) = type;
781 val = value_change_enclosing_type (val, VALUE_ENCLOSING_TYPE (fromval));
782 VALUE_EMBEDDED_OFFSET (val) = VALUE_EMBEDDED_OFFSET (fromval);
783 VALUE_POINTED_TO_OFFSET (val) = VALUE_POINTED_TO_OFFSET (fromval);
784
785 return val;
786 }
787
788 /* Extend a value VAL to COUNT repetitions of its type. */
789
790 struct value *
791 value_repeat (struct value *arg1, int count)
792 {
793 struct value *val;
794
795 if (VALUE_LVAL (arg1) != lval_memory)
796 error ("Only values in memory can be extended with '@'.");
797 if (count < 1)
798 error ("Invalid number %d of repetitions.", count);
799
800 val = allocate_repeat_value (VALUE_ENCLOSING_TYPE (arg1), count);
801
802 read_memory (VALUE_ADDRESS (arg1) + VALUE_OFFSET (arg1),
803 VALUE_CONTENTS_ALL_RAW (val),
804 TYPE_LENGTH (VALUE_ENCLOSING_TYPE (val)));
805 VALUE_LVAL (val) = lval_memory;
806 VALUE_ADDRESS (val) = VALUE_ADDRESS (arg1) + VALUE_OFFSET (arg1);
807
808 return val;
809 }
810
811 struct value *
812 value_of_variable (struct symbol *var, struct block *b)
813 {
814 struct value *val;
815 struct frame_info *frame = NULL;
816
817 if (!b)
818 frame = NULL; /* Use selected frame. */
819 else if (symbol_read_needs_frame (var))
820 {
821 frame = block_innermost_frame (b);
822 if (!frame)
823 {
824 if (BLOCK_FUNCTION (b)
825 && SYMBOL_SOURCE_NAME (BLOCK_FUNCTION (b)))
826 error ("No frame is currently executing in block %s.",
827 SYMBOL_SOURCE_NAME (BLOCK_FUNCTION (b)));
828 else
829 error ("No frame is currently executing in specified block");
830 }
831 }
832
833 val = read_var_value (var, frame);
834 if (!val)
835 error ("Address of symbol \"%s\" is unknown.", SYMBOL_SOURCE_NAME (var));
836
837 return val;
838 }
839
840 /* Given a value which is an array, return a value which is a pointer to its
841 first element, regardless of whether or not the array has a nonzero lower
842 bound.
843
844 FIXME: A previous comment here indicated that this routine should be
845 substracting the array's lower bound. It's not clear to me that this
846 is correct. Given an array subscripting operation, it would certainly
847 work to do the adjustment here, essentially computing:
848
849 (&array[0] - (lowerbound * sizeof array[0])) + (index * sizeof array[0])
850
851 However I believe a more appropriate and logical place to account for
852 the lower bound is to do so in value_subscript, essentially computing:
853
854 (&array[0] + ((index - lowerbound) * sizeof array[0]))
855
856 As further evidence consider what would happen with operations other
857 than array subscripting, where the caller would get back a value that
858 had an address somewhere before the actual first element of the array,
859 and the information about the lower bound would be lost because of
860 the coercion to pointer type.
861 */
862
863 struct value *
864 value_coerce_array (struct value *arg1)
865 {
866 register struct type *type = check_typedef (VALUE_TYPE (arg1));
867
868 if (VALUE_LVAL (arg1) != lval_memory)
869 error ("Attempt to take address of value not located in memory.");
870
871 return value_from_pointer (lookup_pointer_type (TYPE_TARGET_TYPE (type)),
872 (VALUE_ADDRESS (arg1) + VALUE_OFFSET (arg1)));
873 }
874
875 /* Given a value which is a function, return a value which is a pointer
876 to it. */
877
878 struct value *
879 value_coerce_function (struct value *arg1)
880 {
881 struct value *retval;
882
883 if (VALUE_LVAL (arg1) != lval_memory)
884 error ("Attempt to take address of value not located in memory.");
885
886 retval = value_from_pointer (lookup_pointer_type (VALUE_TYPE (arg1)),
887 (VALUE_ADDRESS (arg1) + VALUE_OFFSET (arg1)));
888 VALUE_BFD_SECTION (retval) = VALUE_BFD_SECTION (arg1);
889 return retval;
890 }
891
892 /* Return a pointer value for the object for which ARG1 is the contents. */
893
894 struct value *
895 value_addr (struct value *arg1)
896 {
897 struct value *arg2;
898
899 struct type *type = check_typedef (VALUE_TYPE (arg1));
900 if (TYPE_CODE (type) == TYPE_CODE_REF)
901 {
902 /* Copy the value, but change the type from (T&) to (T*).
903 We keep the same location information, which is efficient,
904 and allows &(&X) to get the location containing the reference. */
905 arg2 = value_copy (arg1);
906 VALUE_TYPE (arg2) = lookup_pointer_type (TYPE_TARGET_TYPE (type));
907 return arg2;
908 }
909 if (TYPE_CODE (type) == TYPE_CODE_FUNC)
910 return value_coerce_function (arg1);
911
912 if (VALUE_LVAL (arg1) != lval_memory)
913 error ("Attempt to take address of value not located in memory.");
914
915 /* Get target memory address */
916 arg2 = value_from_pointer (lookup_pointer_type (VALUE_TYPE (arg1)),
917 (VALUE_ADDRESS (arg1)
918 + VALUE_OFFSET (arg1)
919 + VALUE_EMBEDDED_OFFSET (arg1)));
920
921 /* This may be a pointer to a base subobject; so remember the
922 full derived object's type ... */
923 arg2 = value_change_enclosing_type (arg2, lookup_pointer_type (VALUE_ENCLOSING_TYPE (arg1)));
924 /* ... and also the relative position of the subobject in the full object */
925 VALUE_POINTED_TO_OFFSET (arg2) = VALUE_EMBEDDED_OFFSET (arg1);
926 VALUE_BFD_SECTION (arg2) = VALUE_BFD_SECTION (arg1);
927 return arg2;
928 }
929
930 /* Given a value of a pointer type, apply the C unary * operator to it. */
931
932 struct value *
933 value_ind (struct value *arg1)
934 {
935 struct type *base_type;
936 struct value *arg2;
937
938 COERCE_ARRAY (arg1);
939
940 base_type = check_typedef (VALUE_TYPE (arg1));
941
942 if (TYPE_CODE (base_type) == TYPE_CODE_MEMBER)
943 error ("not implemented: member types in value_ind");
944
945 /* Allow * on an integer so we can cast it to whatever we want.
946 This returns an int, which seems like the most C-like thing
947 to do. "long long" variables are rare enough that
948 BUILTIN_TYPE_LONGEST would seem to be a mistake. */
949 if (TYPE_CODE (base_type) == TYPE_CODE_INT)
950 return value_at_lazy (builtin_type_int,
951 (CORE_ADDR) value_as_long (arg1),
952 VALUE_BFD_SECTION (arg1));
953 else if (TYPE_CODE (base_type) == TYPE_CODE_PTR)
954 {
955 struct type *enc_type;
956 /* We may be pointing to something embedded in a larger object */
957 /* Get the real type of the enclosing object */
958 enc_type = check_typedef (VALUE_ENCLOSING_TYPE (arg1));
959 enc_type = TYPE_TARGET_TYPE (enc_type);
960 /* Retrieve the enclosing object pointed to */
961 arg2 = value_at_lazy (enc_type,
962 value_as_address (arg1) - VALUE_POINTED_TO_OFFSET (arg1),
963 VALUE_BFD_SECTION (arg1));
964 /* Re-adjust type */
965 VALUE_TYPE (arg2) = TYPE_TARGET_TYPE (base_type);
966 /* Add embedding info */
967 arg2 = value_change_enclosing_type (arg2, enc_type);
968 VALUE_EMBEDDED_OFFSET (arg2) = VALUE_POINTED_TO_OFFSET (arg1);
969
970 /* We may be pointing to an object of some derived type */
971 arg2 = value_full_object (arg2, NULL, 0, 0, 0);
972 return arg2;
973 }
974
975 error ("Attempt to take contents of a non-pointer value.");
976 return 0; /* For lint -- never reached */
977 }
978 \f
979 /* Pushing small parts of stack frames. */
980
981 /* Push one word (the size of object that a register holds). */
982
983 CORE_ADDR
984 push_word (CORE_ADDR sp, ULONGEST word)
985 {
986 register int len = REGISTER_SIZE;
987 char *buffer = alloca (MAX_REGISTER_RAW_SIZE);
988
989 store_unsigned_integer (buffer, len, word);
990 if (INNER_THAN (1, 2))
991 {
992 /* stack grows downward */
993 sp -= len;
994 write_memory (sp, buffer, len);
995 }
996 else
997 {
998 /* stack grows upward */
999 write_memory (sp, buffer, len);
1000 sp += len;
1001 }
1002
1003 return sp;
1004 }
1005
1006 /* Push LEN bytes with data at BUFFER. */
1007
1008 CORE_ADDR
1009 push_bytes (CORE_ADDR sp, char *buffer, int len)
1010 {
1011 if (INNER_THAN (1, 2))
1012 {
1013 /* stack grows downward */
1014 sp -= len;
1015 write_memory (sp, buffer, len);
1016 }
1017 else
1018 {
1019 /* stack grows upward */
1020 write_memory (sp, buffer, len);
1021 sp += len;
1022 }
1023
1024 return sp;
1025 }
1026
1027 #ifndef PARM_BOUNDARY
1028 #define PARM_BOUNDARY (0)
1029 #endif
1030
1031 /* Push onto the stack the specified value VALUE. Pad it correctly for
1032 it to be an argument to a function. */
1033
1034 static CORE_ADDR
1035 value_push (register CORE_ADDR sp, struct value *arg)
1036 {
1037 register int len = TYPE_LENGTH (VALUE_ENCLOSING_TYPE (arg));
1038 register int container_len = len;
1039 register int offset;
1040
1041 /* How big is the container we're going to put this value in? */
1042 if (PARM_BOUNDARY)
1043 container_len = ((len + PARM_BOUNDARY / TARGET_CHAR_BIT - 1)
1044 & ~(PARM_BOUNDARY / TARGET_CHAR_BIT - 1));
1045
1046 /* Are we going to put it at the high or low end of the container? */
1047 if (TARGET_BYTE_ORDER == BFD_ENDIAN_BIG)
1048 offset = container_len - len;
1049 else
1050 offset = 0;
1051
1052 if (INNER_THAN (1, 2))
1053 {
1054 /* stack grows downward */
1055 sp -= container_len;
1056 write_memory (sp + offset, VALUE_CONTENTS_ALL (arg), len);
1057 }
1058 else
1059 {
1060 /* stack grows upward */
1061 write_memory (sp + offset, VALUE_CONTENTS_ALL (arg), len);
1062 sp += container_len;
1063 }
1064
1065 return sp;
1066 }
1067
1068 CORE_ADDR
1069 default_push_arguments (int nargs, struct value **args, CORE_ADDR sp,
1070 int struct_return, CORE_ADDR struct_addr)
1071 {
1072 /* ASSERT ( !struct_return); */
1073 int i;
1074 for (i = nargs - 1; i >= 0; i--)
1075 sp = value_push (sp, args[i]);
1076 return sp;
1077 }
1078
1079 /* Perform the standard coercions that are specified
1080 for arguments to be passed to C functions.
1081
1082 If PARAM_TYPE is non-NULL, it is the expected parameter type.
1083 IS_PROTOTYPED is non-zero if the function declaration is prototyped. */
1084
1085 static struct value *
1086 value_arg_coerce (struct value *arg, struct type *param_type,
1087 int is_prototyped)
1088 {
1089 register struct type *arg_type = check_typedef (VALUE_TYPE (arg));
1090 register struct type *type
1091 = param_type ? check_typedef (param_type) : arg_type;
1092
1093 switch (TYPE_CODE (type))
1094 {
1095 case TYPE_CODE_REF:
1096 if (TYPE_CODE (arg_type) != TYPE_CODE_REF
1097 && TYPE_CODE (arg_type) != TYPE_CODE_PTR)
1098 {
1099 arg = value_addr (arg);
1100 VALUE_TYPE (arg) = param_type;
1101 return arg;
1102 }
1103 break;
1104 case TYPE_CODE_INT:
1105 case TYPE_CODE_CHAR:
1106 case TYPE_CODE_BOOL:
1107 case TYPE_CODE_ENUM:
1108 /* If we don't have a prototype, coerce to integer type if necessary. */
1109 if (!is_prototyped)
1110 {
1111 if (TYPE_LENGTH (type) < TYPE_LENGTH (builtin_type_int))
1112 type = builtin_type_int;
1113 }
1114 /* Currently all target ABIs require at least the width of an integer
1115 type for an argument. We may have to conditionalize the following
1116 type coercion for future targets. */
1117 if (TYPE_LENGTH (type) < TYPE_LENGTH (builtin_type_int))
1118 type = builtin_type_int;
1119 break;
1120 case TYPE_CODE_FLT:
1121 if (!is_prototyped && coerce_float_to_double)
1122 {
1123 if (TYPE_LENGTH (type) < TYPE_LENGTH (builtin_type_double))
1124 type = builtin_type_double;
1125 else if (TYPE_LENGTH (type) > TYPE_LENGTH (builtin_type_double))
1126 type = builtin_type_long_double;
1127 }
1128 break;
1129 case TYPE_CODE_FUNC:
1130 type = lookup_pointer_type (type);
1131 break;
1132 case TYPE_CODE_ARRAY:
1133 /* Arrays are coerced to pointers to their first element, unless
1134 they are vectors, in which case we want to leave them alone,
1135 because they are passed by value. */
1136 if (current_language->c_style_arrays)
1137 if (!TYPE_VECTOR (type))
1138 type = lookup_pointer_type (TYPE_TARGET_TYPE (type));
1139 break;
1140 case TYPE_CODE_UNDEF:
1141 case TYPE_CODE_PTR:
1142 case TYPE_CODE_STRUCT:
1143 case TYPE_CODE_UNION:
1144 case TYPE_CODE_VOID:
1145 case TYPE_CODE_SET:
1146 case TYPE_CODE_RANGE:
1147 case TYPE_CODE_STRING:
1148 case TYPE_CODE_BITSTRING:
1149 case TYPE_CODE_ERROR:
1150 case TYPE_CODE_MEMBER:
1151 case TYPE_CODE_METHOD:
1152 case TYPE_CODE_COMPLEX:
1153 default:
1154 break;
1155 }
1156
1157 return value_cast (type, arg);
1158 }
1159
1160 /* Determine a function's address and its return type from its value.
1161 Calls error() if the function is not valid for calling. */
1162
1163 static CORE_ADDR
1164 find_function_addr (struct value *function, struct type **retval_type)
1165 {
1166 register struct type *ftype = check_typedef (VALUE_TYPE (function));
1167 register enum type_code code = TYPE_CODE (ftype);
1168 struct type *value_type;
1169 CORE_ADDR funaddr;
1170
1171 /* If it's a member function, just look at the function
1172 part of it. */
1173
1174 /* Determine address to call. */
1175 if (code == TYPE_CODE_FUNC || code == TYPE_CODE_METHOD)
1176 {
1177 funaddr = VALUE_ADDRESS (function);
1178 value_type = TYPE_TARGET_TYPE (ftype);
1179 }
1180 else if (code == TYPE_CODE_PTR)
1181 {
1182 funaddr = value_as_address (function);
1183 ftype = check_typedef (TYPE_TARGET_TYPE (ftype));
1184 if (TYPE_CODE (ftype) == TYPE_CODE_FUNC
1185 || TYPE_CODE (ftype) == TYPE_CODE_METHOD)
1186 {
1187 funaddr = CONVERT_FROM_FUNC_PTR_ADDR (funaddr);
1188 value_type = TYPE_TARGET_TYPE (ftype);
1189 }
1190 else
1191 value_type = builtin_type_int;
1192 }
1193 else if (code == TYPE_CODE_INT)
1194 {
1195 /* Handle the case of functions lacking debugging info.
1196 Their values are characters since their addresses are char */
1197 if (TYPE_LENGTH (ftype) == 1)
1198 funaddr = value_as_address (value_addr (function));
1199 else
1200 /* Handle integer used as address of a function. */
1201 funaddr = (CORE_ADDR) value_as_long (function);
1202
1203 value_type = builtin_type_int;
1204 }
1205 else
1206 error ("Invalid data type for function to be called.");
1207
1208 *retval_type = value_type;
1209 return funaddr;
1210 }
1211
1212 /* All this stuff with a dummy frame may seem unnecessarily complicated
1213 (why not just save registers in GDB?). The purpose of pushing a dummy
1214 frame which looks just like a real frame is so that if you call a
1215 function and then hit a breakpoint (get a signal, etc), "backtrace"
1216 will look right. Whether the backtrace needs to actually show the
1217 stack at the time the inferior function was called is debatable, but
1218 it certainly needs to not display garbage. So if you are contemplating
1219 making dummy frames be different from normal frames, consider that. */
1220
1221 /* Perform a function call in the inferior.
1222 ARGS is a vector of values of arguments (NARGS of them).
1223 FUNCTION is a value, the function to be called.
1224 Returns a value representing what the function returned.
1225 May fail to return, if a breakpoint or signal is hit
1226 during the execution of the function.
1227
1228 ARGS is modified to contain coerced values. */
1229
1230 static struct value *
1231 hand_function_call (struct value *function, int nargs, struct value **args)
1232 {
1233 register CORE_ADDR sp;
1234 register int i;
1235 int rc;
1236 CORE_ADDR start_sp;
1237 /* CALL_DUMMY is an array of words (REGISTER_SIZE), but each word
1238 is in host byte order. Before calling FIX_CALL_DUMMY, we byteswap it
1239 and remove any extra bytes which might exist because ULONGEST is
1240 bigger than REGISTER_SIZE.
1241
1242 NOTE: This is pretty wierd, as the call dummy is actually a
1243 sequence of instructions. But CISC machines will have
1244 to pack the instructions into REGISTER_SIZE units (and
1245 so will RISC machines for which INSTRUCTION_SIZE is not
1246 REGISTER_SIZE).
1247
1248 NOTE: This is pretty stupid. CALL_DUMMY should be in strict
1249 target byte order. */
1250
1251 static ULONGEST *dummy;
1252 int sizeof_dummy1;
1253 char *dummy1;
1254 CORE_ADDR old_sp;
1255 struct type *value_type;
1256 unsigned char struct_return;
1257 CORE_ADDR struct_addr = 0;
1258 struct regcache *retbuf;
1259 struct cleanup *retbuf_cleanup;
1260 struct inferior_status *inf_status;
1261 struct cleanup *inf_status_cleanup;
1262 CORE_ADDR funaddr;
1263 int using_gcc; /* Set to version of gcc in use, or zero if not gcc */
1264 CORE_ADDR real_pc;
1265 struct type *param_type = NULL;
1266 struct type *ftype = check_typedef (SYMBOL_TYPE (function));
1267 int n_method_args = 0;
1268
1269 dummy = alloca (SIZEOF_CALL_DUMMY_WORDS);
1270 sizeof_dummy1 = REGISTER_SIZE * SIZEOF_CALL_DUMMY_WORDS / sizeof (ULONGEST);
1271 dummy1 = alloca (sizeof_dummy1);
1272 memcpy (dummy, CALL_DUMMY_WORDS, SIZEOF_CALL_DUMMY_WORDS);
1273
1274 if (!target_has_execution)
1275 noprocess ();
1276
1277 /* Create a cleanup chain that contains the retbuf (buffer
1278 containing the register values). This chain is create BEFORE the
1279 inf_status chain so that the inferior status can cleaned up
1280 (restored or discarded) without having the retbuf freed. */
1281 retbuf = regcache_xmalloc (current_gdbarch);
1282 retbuf_cleanup = make_cleanup_regcache_xfree (retbuf);
1283
1284 /* A cleanup for the inferior status. Create this AFTER the retbuf
1285 so that this can be discarded or applied without interfering with
1286 the regbuf. */
1287 inf_status = save_inferior_status (1);
1288 inf_status_cleanup = make_cleanup_restore_inferior_status (inf_status);
1289
1290 /* PUSH_DUMMY_FRAME is responsible for saving the inferior registers
1291 (and POP_FRAME for restoring them). (At least on most machines)
1292 they are saved on the stack in the inferior. */
1293 PUSH_DUMMY_FRAME;
1294
1295 old_sp = read_sp ();
1296
1297 /* Ensure that the initial SP is correctly aligned. */
1298 if (gdbarch_frame_align_p (current_gdbarch))
1299 {
1300 /* NOTE: cagney/2002-09-18:
1301
1302 On a RISC architecture, a void parameterless generic dummy
1303 frame (i.e., no parameters, no result) typically does not
1304 need to push anything the stack and hence can leave SP and
1305 FP. Similarly, a framelss (possibly leaf) function does not
1306 push anything on the stack and, hence, that too can leave FP
1307 and SP unchanged. As a consequence, a sequence of void
1308 parameterless generic dummy frame calls to frameless
1309 functions will create a sequence of effectively identical
1310 frames (SP, FP and TOS and PC the same). This, not
1311 suprisingly, results in what appears to be a stack in an
1312 infinite loop --- when GDB tries to find a generic dummy
1313 frame on the internal dummy frame stack, it will always find
1314 the first one.
1315
1316 To avoid this problem, the code below always grows the stack.
1317 That way, two dummy frames can never be identical. It does
1318 burn a few bytes of stack but that is a small price to pay
1319 :-). */
1320 sp = gdbarch_frame_align (current_gdbarch, old_sp);
1321 if (sp == old_sp)
1322 {
1323 if (INNER_THAN (1, 2))
1324 /* Stack grows down. */
1325 sp = gdbarch_frame_align (current_gdbarch, old_sp - 1);
1326 else
1327 /* Stack grows up. */
1328 sp = gdbarch_frame_align (current_gdbarch, old_sp + 1);
1329 }
1330 gdb_assert ((INNER_THAN (1, 2) && sp <= old_sp)
1331 || (INNER_THAN (2, 1) && sp >= old_sp));
1332 }
1333 else
1334 /* FIXME: cagney/2002-09-18: Hey, you loose! Who knows how badly
1335 aligned the SP is! Further, per comment above, if the generic
1336 dummy frame ends up empty (because nothing is pushed) GDB won't
1337 be able to correctly perform back traces. If a target is
1338 having trouble with backtraces, first thing to do is add
1339 FRAME_ALIGN() to its architecture vector. After that, try
1340 adding SAVE_DUMMY_FRAME_TOS() and modifying FRAME_CHAIN so that
1341 when the next outer frame is a generic dummy, it returns the
1342 current frame's base. */
1343 sp = old_sp;
1344
1345 if (INNER_THAN (1, 2))
1346 {
1347 /* Stack grows down */
1348 sp -= sizeof_dummy1;
1349 start_sp = sp;
1350 }
1351 else
1352 {
1353 /* Stack grows up */
1354 start_sp = sp;
1355 sp += sizeof_dummy1;
1356 }
1357
1358 /* NOTE: cagney/2002-09-10: Don't bother re-adjusting the stack
1359 after allocating space for the call dummy. A target can specify
1360 a SIZEOF_DUMMY1 (via SIZEOF_CALL_DUMMY_WORDS) such that all local
1361 alignment requirements are met. */
1362
1363 funaddr = find_function_addr (function, &value_type);
1364 CHECK_TYPEDEF (value_type);
1365
1366 {
1367 struct block *b = block_for_pc (funaddr);
1368 /* If compiled without -g, assume GCC 2. */
1369 using_gcc = (b == NULL ? 2 : BLOCK_GCC_COMPILED (b));
1370 }
1371
1372 /* Are we returning a value using a structure return or a normal
1373 value return? */
1374
1375 struct_return = using_struct_return (function, funaddr, value_type,
1376 using_gcc);
1377
1378 /* Create a call sequence customized for this function
1379 and the number of arguments for it. */
1380 for (i = 0; i < (int) (SIZEOF_CALL_DUMMY_WORDS / sizeof (dummy[0])); i++)
1381 store_unsigned_integer (&dummy1[i * REGISTER_SIZE],
1382 REGISTER_SIZE,
1383 (ULONGEST) dummy[i]);
1384
1385 #ifdef GDB_TARGET_IS_HPPA
1386 real_pc = FIX_CALL_DUMMY (dummy1, start_sp, funaddr, nargs, args,
1387 value_type, using_gcc);
1388 #else
1389 FIX_CALL_DUMMY (dummy1, start_sp, funaddr, nargs, args,
1390 value_type, using_gcc);
1391 real_pc = start_sp;
1392 #endif
1393
1394 if (CALL_DUMMY_LOCATION == ON_STACK)
1395 {
1396 write_memory (start_sp, (char *) dummy1, sizeof_dummy1);
1397 if (DEPRECATED_USE_GENERIC_DUMMY_FRAMES)
1398 generic_save_call_dummy_addr (start_sp, start_sp + sizeof_dummy1);
1399 }
1400
1401 if (CALL_DUMMY_LOCATION == AT_ENTRY_POINT)
1402 {
1403 real_pc = funaddr;
1404 if (DEPRECATED_USE_GENERIC_DUMMY_FRAMES)
1405 /* NOTE: cagney/2002-04-13: The entry point is going to be
1406 modified with a single breakpoint. */
1407 generic_save_call_dummy_addr (CALL_DUMMY_ADDRESS (),
1408 CALL_DUMMY_ADDRESS () + 1);
1409 }
1410
1411 #ifdef lint
1412 sp = old_sp; /* It really is used, for some ifdef's... */
1413 #endif
1414
1415 if (nargs < TYPE_NFIELDS (ftype))
1416 error ("too few arguments in function call");
1417
1418 for (i = nargs - 1; i >= 0; i--)
1419 {
1420 int prototyped;
1421
1422 /* FIXME drow/2002-05-31: Should just always mark methods as
1423 prototyped. Can we respect TYPE_VARARGS? Probably not. */
1424 if (TYPE_CODE (ftype) == TYPE_CODE_METHOD)
1425 prototyped = 1;
1426 else
1427 prototyped = TYPE_PROTOTYPED (ftype);
1428
1429 if (i < TYPE_NFIELDS (ftype))
1430 args[i] = value_arg_coerce (args[i], TYPE_FIELD_TYPE (ftype, i),
1431 prototyped);
1432 else
1433 args[i] = value_arg_coerce (args[i], NULL, 0);
1434
1435 /*elz: this code is to handle the case in which the function to be called
1436 has a pointer to function as parameter and the corresponding actual argument
1437 is the address of a function and not a pointer to function variable.
1438 In aCC compiled code, the calls through pointers to functions (in the body
1439 of the function called by hand) are made via $$dyncall_external which
1440 requires some registers setting, this is taken care of if we call
1441 via a function pointer variable, but not via a function address.
1442 In cc this is not a problem. */
1443
1444 if (using_gcc == 0)
1445 if (param_type && TYPE_CODE (ftype) != TYPE_CODE_METHOD)
1446 /* if this parameter is a pointer to function */
1447 if (TYPE_CODE (param_type) == TYPE_CODE_PTR)
1448 if (TYPE_CODE (TYPE_TARGET_TYPE (param_type)) == TYPE_CODE_FUNC)
1449 /* elz: FIXME here should go the test about the compiler used
1450 to compile the target. We want to issue the error
1451 message only if the compiler used was HP's aCC.
1452 If we used HP's cc, then there is no problem and no need
1453 to return at this point */
1454 if (using_gcc == 0) /* && compiler == aCC */
1455 /* go see if the actual parameter is a variable of type
1456 pointer to function or just a function */
1457 if (args[i]->lval == not_lval)
1458 {
1459 char *arg_name;
1460 if (find_pc_partial_function ((CORE_ADDR) args[i]->aligner.contents[0], &arg_name, NULL, NULL))
1461 error ("\
1462 You cannot use function <%s> as argument. \n\
1463 You must use a pointer to function type variable. Command ignored.", arg_name);
1464 }
1465 }
1466
1467 if (REG_STRUCT_HAS_ADDR_P ())
1468 {
1469 /* This is a machine like the sparc, where we may need to pass a
1470 pointer to the structure, not the structure itself. */
1471 for (i = nargs - 1; i >= 0; i--)
1472 {
1473 struct type *arg_type = check_typedef (VALUE_TYPE (args[i]));
1474 if ((TYPE_CODE (arg_type) == TYPE_CODE_STRUCT
1475 || TYPE_CODE (arg_type) == TYPE_CODE_UNION
1476 || TYPE_CODE (arg_type) == TYPE_CODE_ARRAY
1477 || TYPE_CODE (arg_type) == TYPE_CODE_STRING
1478 || TYPE_CODE (arg_type) == TYPE_CODE_BITSTRING
1479 || TYPE_CODE (arg_type) == TYPE_CODE_SET
1480 || (TYPE_CODE (arg_type) == TYPE_CODE_FLT
1481 && TYPE_LENGTH (arg_type) > 8)
1482 )
1483 && REG_STRUCT_HAS_ADDR (using_gcc, arg_type))
1484 {
1485 CORE_ADDR addr;
1486 int len; /* = TYPE_LENGTH (arg_type); */
1487 int aligned_len;
1488 arg_type = check_typedef (VALUE_ENCLOSING_TYPE (args[i]));
1489 len = TYPE_LENGTH (arg_type);
1490
1491 if (STACK_ALIGN_P ())
1492 /* MVS 11/22/96: I think at least some of this
1493 stack_align code is really broken. Better to let
1494 PUSH_ARGUMENTS adjust the stack in a target-defined
1495 manner. */
1496 aligned_len = STACK_ALIGN (len);
1497 else
1498 aligned_len = len;
1499 if (INNER_THAN (1, 2))
1500 {
1501 /* stack grows downward */
1502 sp -= aligned_len;
1503 /* ... so the address of the thing we push is the
1504 stack pointer after we push it. */
1505 addr = sp;
1506 }
1507 else
1508 {
1509 /* The stack grows up, so the address of the thing
1510 we push is the stack pointer before we push it. */
1511 addr = sp;
1512 sp += aligned_len;
1513 }
1514 /* Push the structure. */
1515 write_memory (addr, VALUE_CONTENTS_ALL (args[i]), len);
1516 /* The value we're going to pass is the address of the
1517 thing we just pushed. */
1518 /*args[i] = value_from_longest (lookup_pointer_type (value_type),
1519 (LONGEST) addr); */
1520 args[i] = value_from_pointer (lookup_pointer_type (arg_type),
1521 addr);
1522 }
1523 }
1524 }
1525
1526
1527 /* Reserve space for the return structure to be written on the
1528 stack, if necessary. Make certain that the value is correctly
1529 aligned. */
1530
1531 if (struct_return)
1532 {
1533 int len = TYPE_LENGTH (value_type);
1534 if (STACK_ALIGN_P ())
1535 /* MVS 11/22/96: I think at least some of this stack_align
1536 code is really broken. Better to let PUSH_ARGUMENTS adjust
1537 the stack in a target-defined manner. */
1538 len = STACK_ALIGN (len);
1539 if (INNER_THAN (1, 2))
1540 {
1541 /* Stack grows downward. Align STRUCT_ADDR and SP after
1542 making space for the return value. */
1543 sp -= len;
1544 if (gdbarch_frame_align_p (current_gdbarch))
1545 sp = gdbarch_frame_align (current_gdbarch, sp);
1546 struct_addr = sp;
1547 }
1548 else
1549 {
1550 /* Stack grows upward. Align the frame, allocate space, and
1551 then again, re-align the frame??? */
1552 if (gdbarch_frame_align_p (current_gdbarch))
1553 sp = gdbarch_frame_align (current_gdbarch, sp);
1554 struct_addr = sp;
1555 sp += len;
1556 if (gdbarch_frame_align_p (current_gdbarch))
1557 sp = gdbarch_frame_align (current_gdbarch, sp);
1558 }
1559 }
1560
1561 /* elz: on HPPA no need for this extra alignment, maybe it is needed
1562 on other architectures. This is because all the alignment is
1563 taken care of in the above code (ifdef REG_STRUCT_HAS_ADDR) and
1564 in hppa_push_arguments */
1565 if (EXTRA_STACK_ALIGNMENT_NEEDED)
1566 {
1567 /* MVS 11/22/96: I think at least some of this stack_align code
1568 is really broken. Better to let PUSH_ARGUMENTS adjust the
1569 stack in a target-defined manner. */
1570 if (STACK_ALIGN_P () && INNER_THAN (1, 2))
1571 {
1572 /* If stack grows down, we must leave a hole at the top. */
1573 int len = 0;
1574
1575 for (i = nargs - 1; i >= 0; i--)
1576 len += TYPE_LENGTH (VALUE_ENCLOSING_TYPE (args[i]));
1577 if (CALL_DUMMY_STACK_ADJUST_P)
1578 len += CALL_DUMMY_STACK_ADJUST;
1579 sp -= STACK_ALIGN (len) - len;
1580 }
1581 }
1582
1583 sp = PUSH_ARGUMENTS (nargs, args, sp, struct_return, struct_addr);
1584
1585 if (PUSH_RETURN_ADDRESS_P ())
1586 /* for targets that use no CALL_DUMMY */
1587 /* There are a number of targets now which actually don't write
1588 any CALL_DUMMY instructions into the target, but instead just
1589 save the machine state, push the arguments, and jump directly
1590 to the callee function. Since this doesn't actually involve
1591 executing a JSR/BSR instruction, the return address must be set
1592 up by hand, either by pushing onto the stack or copying into a
1593 return-address register as appropriate. Formerly this has been
1594 done in PUSH_ARGUMENTS, but that's overloading its
1595 functionality a bit, so I'm making it explicit to do it here. */
1596 sp = PUSH_RETURN_ADDRESS (real_pc, sp);
1597
1598 if (STACK_ALIGN_P () && !INNER_THAN (1, 2))
1599 {
1600 /* If stack grows up, we must leave a hole at the bottom, note
1601 that sp already has been advanced for the arguments! */
1602 if (CALL_DUMMY_STACK_ADJUST_P)
1603 sp += CALL_DUMMY_STACK_ADJUST;
1604 sp = STACK_ALIGN (sp);
1605 }
1606
1607 /* XXX This seems wrong. For stacks that grow down we shouldn't do
1608 anything here! */
1609 /* MVS 11/22/96: I think at least some of this stack_align code is
1610 really broken. Better to let PUSH_ARGUMENTS adjust the stack in
1611 a target-defined manner. */
1612 if (CALL_DUMMY_STACK_ADJUST_P)
1613 if (INNER_THAN (1, 2))
1614 {
1615 /* stack grows downward */
1616 sp -= CALL_DUMMY_STACK_ADJUST;
1617 }
1618
1619 /* Store the address at which the structure is supposed to be
1620 written. Note that this (and the code which reserved the space
1621 above) assumes that gcc was used to compile this function. Since
1622 it doesn't cost us anything but space and if the function is pcc
1623 it will ignore this value, we will make that assumption.
1624
1625 Also note that on some machines (like the sparc) pcc uses a
1626 convention like gcc's. */
1627
1628 if (struct_return)
1629 STORE_STRUCT_RETURN (struct_addr, sp);
1630
1631 /* Write the stack pointer. This is here because the statements above
1632 might fool with it. On SPARC, this write also stores the register
1633 window into the right place in the new stack frame, which otherwise
1634 wouldn't happen. (See store_inferior_registers in sparc-nat.c.) */
1635 write_sp (sp);
1636
1637 if (SAVE_DUMMY_FRAME_TOS_P ())
1638 SAVE_DUMMY_FRAME_TOS (sp);
1639
1640 {
1641 char *name;
1642 struct symbol *symbol;
1643
1644 name = NULL;
1645 symbol = find_pc_function (funaddr);
1646 if (symbol)
1647 {
1648 name = SYMBOL_SOURCE_NAME (symbol);
1649 }
1650 else
1651 {
1652 /* Try the minimal symbols. */
1653 struct minimal_symbol *msymbol = lookup_minimal_symbol_by_pc (funaddr);
1654
1655 if (msymbol)
1656 {
1657 name = SYMBOL_SOURCE_NAME (msymbol);
1658 }
1659 }
1660 if (name == NULL)
1661 {
1662 char format[80];
1663 sprintf (format, "at %s", local_hex_format ());
1664 name = alloca (80);
1665 /* FIXME-32x64: assumes funaddr fits in a long. */
1666 sprintf (name, format, (unsigned long) funaddr);
1667 }
1668
1669 /* Execute the stack dummy routine, calling FUNCTION.
1670 When it is done, discard the empty frame
1671 after storing the contents of all regs into retbuf. */
1672 rc = run_stack_dummy (real_pc + CALL_DUMMY_START_OFFSET, retbuf);
1673
1674 if (rc == 1)
1675 {
1676 /* We stopped inside the FUNCTION because of a random signal.
1677 Further execution of the FUNCTION is not allowed. */
1678
1679 if (unwind_on_signal_p)
1680 {
1681 /* The user wants the context restored. */
1682
1683 /* We must get back to the frame we were before the dummy
1684 call. */
1685 frame_pop (get_current_frame ());
1686
1687 /* FIXME: Insert a bunch of wrap_here; name can be very long if it's
1688 a C++ name with arguments and stuff. */
1689 error ("\
1690 The program being debugged was signaled while in a function called from GDB.\n\
1691 GDB has restored the context to what it was before the call.\n\
1692 To change this behavior use \"set unwindonsignal off\"\n\
1693 Evaluation of the expression containing the function (%s) will be abandoned.",
1694 name);
1695 }
1696 else
1697 {
1698 /* The user wants to stay in the frame where we stopped (default).*/
1699
1700 /* If we restored the inferior status (via the cleanup),
1701 we would print a spurious error message (Unable to
1702 restore previously selected frame), would write the
1703 registers from the inf_status (which is wrong), and
1704 would do other wrong things. */
1705 discard_cleanups (inf_status_cleanup);
1706 discard_inferior_status (inf_status);
1707
1708 /* FIXME: Insert a bunch of wrap_here; name can be very long if it's
1709 a C++ name with arguments and stuff. */
1710 error ("\
1711 The program being debugged was signaled while in a function called from GDB.\n\
1712 GDB remains in the frame where the signal was received.\n\
1713 To change this behavior use \"set unwindonsignal on\"\n\
1714 Evaluation of the expression containing the function (%s) will be abandoned.",
1715 name);
1716 }
1717 }
1718
1719 if (rc == 2)
1720 {
1721 /* We hit a breakpoint inside the FUNCTION. */
1722
1723 /* If we restored the inferior status (via the cleanup), we
1724 would print a spurious error message (Unable to restore
1725 previously selected frame), would write the registers from
1726 the inf_status (which is wrong), and would do other wrong
1727 things. */
1728 discard_cleanups (inf_status_cleanup);
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
1749 /* Restore the inferior status, via its cleanup. At this stage,
1750 leave the RETBUF alone. */
1751 do_cleanups (inf_status_cleanup);
1752
1753 /* Figure out the value returned by the function. */
1754 /* elz: I defined this new macro for the hppa architecture only.
1755 this gives us a way to get the value returned by the function
1756 from the stack, at the same address we told the function to put
1757 it. We cannot assume on the pa that r28 still contains the
1758 address of the returned structure. Usually this will be
1759 overwritten by the callee. I don't know about other
1760 architectures, so I defined this macro */
1761 #ifdef VALUE_RETURNED_FROM_STACK
1762 if (struct_return)
1763 {
1764 do_cleanups (retbuf_cleanup);
1765 return VALUE_RETURNED_FROM_STACK (value_type, struct_addr);
1766 }
1767 #endif
1768 /* NOTE: cagney/2002-09-10: Only when the stack has been correctly
1769 aligned (using frame_align()) do we can trust STRUCT_ADDR and
1770 fetch the return value direct from the stack. This lack of
1771 trust comes about because legacy targets have a nasty habit of
1772 silently, and local to PUSH_ARGUMENTS(), moving STRUCT_ADDR.
1773 For such targets, just hope that value_being_returned() can
1774 find the adjusted value. */
1775 if (struct_return && gdbarch_frame_align_p (current_gdbarch))
1776 {
1777 struct value *retval = value_at (value_type, struct_addr, NULL);
1778 do_cleanups (retbuf_cleanup);
1779 return retval;
1780 }
1781 else
1782 {
1783 struct value *retval = value_being_returned (value_type, retbuf,
1784 struct_return);
1785 do_cleanups (retbuf_cleanup);
1786 return retval;
1787 }
1788 }
1789 }
1790
1791 struct value *
1792 call_function_by_hand (struct value *function, int nargs, struct value **args)
1793 {
1794 if (CALL_DUMMY_P)
1795 {
1796 return hand_function_call (function, nargs, args);
1797 }
1798 else
1799 {
1800 error ("Cannot invoke functions on this machine.");
1801 }
1802 }
1803 \f
1804
1805
1806 /* Create a value for an array by allocating space in the inferior, copying
1807 the data into that space, and then setting up an array value.
1808
1809 The array bounds are set from LOWBOUND and HIGHBOUND, and the array is
1810 populated from the values passed in ELEMVEC.
1811
1812 The element type of the array is inherited from the type of the
1813 first element, and all elements must have the same size (though we
1814 don't currently enforce any restriction on their types). */
1815
1816 struct value *
1817 value_array (int lowbound, int highbound, struct value **elemvec)
1818 {
1819 int nelem;
1820 int idx;
1821 unsigned int typelength;
1822 struct value *val;
1823 struct type *rangetype;
1824 struct type *arraytype;
1825 CORE_ADDR addr;
1826
1827 /* Validate that the bounds are reasonable and that each of the elements
1828 have the same size. */
1829
1830 nelem = highbound - lowbound + 1;
1831 if (nelem <= 0)
1832 {
1833 error ("bad array bounds (%d, %d)", lowbound, highbound);
1834 }
1835 typelength = TYPE_LENGTH (VALUE_ENCLOSING_TYPE (elemvec[0]));
1836 for (idx = 1; idx < nelem; idx++)
1837 {
1838 if (TYPE_LENGTH (VALUE_ENCLOSING_TYPE (elemvec[idx])) != typelength)
1839 {
1840 error ("array elements must all be the same size");
1841 }
1842 }
1843
1844 rangetype = create_range_type ((struct type *) NULL, builtin_type_int,
1845 lowbound, highbound);
1846 arraytype = create_array_type ((struct type *) NULL,
1847 VALUE_ENCLOSING_TYPE (elemvec[0]), rangetype);
1848
1849 if (!current_language->c_style_arrays)
1850 {
1851 val = allocate_value (arraytype);
1852 for (idx = 0; idx < nelem; idx++)
1853 {
1854 memcpy (VALUE_CONTENTS_ALL_RAW (val) + (idx * typelength),
1855 VALUE_CONTENTS_ALL (elemvec[idx]),
1856 typelength);
1857 }
1858 VALUE_BFD_SECTION (val) = VALUE_BFD_SECTION (elemvec[0]);
1859 return val;
1860 }
1861
1862 /* Allocate space to store the array in the inferior, and then initialize
1863 it by copying in each element. FIXME: Is it worth it to create a
1864 local buffer in which to collect each value and then write all the
1865 bytes in one operation? */
1866
1867 addr = allocate_space_in_inferior (nelem * typelength);
1868 for (idx = 0; idx < nelem; idx++)
1869 {
1870 write_memory (addr + (idx * typelength), VALUE_CONTENTS_ALL (elemvec[idx]),
1871 typelength);
1872 }
1873
1874 /* Create the array type and set up an array value to be evaluated lazily. */
1875
1876 val = value_at_lazy (arraytype, addr, VALUE_BFD_SECTION (elemvec[0]));
1877 return (val);
1878 }
1879
1880 /* Create a value for a string constant by allocating space in the inferior,
1881 copying the data into that space, and returning the address with type
1882 TYPE_CODE_STRING. PTR points to the string constant data; LEN is number
1883 of characters.
1884 Note that string types are like array of char types with a lower bound of
1885 zero and an upper bound of LEN - 1. Also note that the string may contain
1886 embedded null bytes. */
1887
1888 struct value *
1889 value_string (char *ptr, int len)
1890 {
1891 struct value *val;
1892 int lowbound = current_language->string_lower_bound;
1893 struct type *rangetype = create_range_type ((struct type *) NULL,
1894 builtin_type_int,
1895 lowbound, len + lowbound - 1);
1896 struct type *stringtype
1897 = create_string_type ((struct type *) NULL, rangetype);
1898 CORE_ADDR addr;
1899
1900 if (current_language->c_style_arrays == 0)
1901 {
1902 val = allocate_value (stringtype);
1903 memcpy (VALUE_CONTENTS_RAW (val), ptr, len);
1904 return val;
1905 }
1906
1907
1908 /* Allocate space to store the string in the inferior, and then
1909 copy LEN bytes from PTR in gdb to that address in the inferior. */
1910
1911 addr = allocate_space_in_inferior (len);
1912 write_memory (addr, ptr, len);
1913
1914 val = value_at_lazy (stringtype, addr, NULL);
1915 return (val);
1916 }
1917
1918 struct value *
1919 value_bitstring (char *ptr, int len)
1920 {
1921 struct value *val;
1922 struct type *domain_type = create_range_type (NULL, builtin_type_int,
1923 0, len - 1);
1924 struct type *type = create_set_type ((struct type *) NULL, domain_type);
1925 TYPE_CODE (type) = TYPE_CODE_BITSTRING;
1926 val = allocate_value (type);
1927 memcpy (VALUE_CONTENTS_RAW (val), ptr, TYPE_LENGTH (type));
1928 return val;
1929 }
1930 \f
1931 /* See if we can pass arguments in T2 to a function which takes arguments
1932 of types T1. T1 is a list of NARGS arguments, and T2 is a NULL-terminated
1933 vector. If some arguments need coercion of some sort, then the coerced
1934 values are written into T2. Return value is 0 if the arguments could be
1935 matched, or the position at which they differ if not.
1936
1937 STATICP is nonzero if the T1 argument list came from a
1938 static member function. T2 will still include the ``this'' pointer,
1939 but it will be skipped.
1940
1941 For non-static member functions, we ignore the first argument,
1942 which is the type of the instance variable. This is because we want
1943 to handle calls with objects from derived classes. This is not
1944 entirely correct: we should actually check to make sure that a
1945 requested operation is type secure, shouldn't we? FIXME. */
1946
1947 static int
1948 typecmp (int staticp, int varargs, int nargs,
1949 struct field t1[], struct value *t2[])
1950 {
1951 int i;
1952
1953 if (t2 == 0)
1954 internal_error (__FILE__, __LINE__, "typecmp: no argument list");
1955
1956 /* Skip ``this'' argument if applicable. T2 will always include THIS. */
1957 if (staticp)
1958 t2 ++;
1959
1960 for (i = 0;
1961 (i < nargs) && TYPE_CODE (t1[i].type) != TYPE_CODE_VOID;
1962 i++)
1963 {
1964 struct type *tt1, *tt2;
1965
1966 if (!t2[i])
1967 return i + 1;
1968
1969 tt1 = check_typedef (t1[i].type);
1970 tt2 = check_typedef (VALUE_TYPE (t2[i]));
1971
1972 if (TYPE_CODE (tt1) == TYPE_CODE_REF
1973 /* We should be doing hairy argument matching, as below. */
1974 && (TYPE_CODE (check_typedef (TYPE_TARGET_TYPE (tt1))) == TYPE_CODE (tt2)))
1975 {
1976 if (TYPE_CODE (tt2) == TYPE_CODE_ARRAY)
1977 t2[i] = value_coerce_array (t2[i]);
1978 else
1979 t2[i] = value_addr (t2[i]);
1980 continue;
1981 }
1982
1983 /* djb - 20000715 - Until the new type structure is in the
1984 place, and we can attempt things like implicit conversions,
1985 we need to do this so you can take something like a map<const
1986 char *>, and properly access map["hello"], because the
1987 argument to [] will be a reference to a pointer to a char,
1988 and the argument will be a pointer to a char. */
1989 while ( TYPE_CODE(tt1) == TYPE_CODE_REF ||
1990 TYPE_CODE (tt1) == TYPE_CODE_PTR)
1991 {
1992 tt1 = check_typedef( TYPE_TARGET_TYPE(tt1) );
1993 }
1994 while ( TYPE_CODE(tt2) == TYPE_CODE_ARRAY ||
1995 TYPE_CODE(tt2) == TYPE_CODE_PTR ||
1996 TYPE_CODE(tt2) == TYPE_CODE_REF)
1997 {
1998 tt2 = check_typedef( TYPE_TARGET_TYPE(tt2) );
1999 }
2000 if (TYPE_CODE (tt1) == TYPE_CODE (tt2))
2001 continue;
2002 /* Array to pointer is a `trivial conversion' according to the ARM. */
2003
2004 /* We should be doing much hairier argument matching (see section 13.2
2005 of the ARM), but as a quick kludge, just check for the same type
2006 code. */
2007 if (TYPE_CODE (t1[i].type) != TYPE_CODE (VALUE_TYPE (t2[i])))
2008 return i + 1;
2009 }
2010 if (varargs || t2[i] == NULL)
2011 return 0;
2012 return i + 1;
2013 }
2014
2015 /* Helper function used by value_struct_elt to recurse through baseclasses.
2016 Look for a field NAME in ARG1. Adjust the address of ARG1 by OFFSET bytes,
2017 and search in it assuming it has (class) type TYPE.
2018 If found, return value, else return NULL.
2019
2020 If LOOKING_FOR_BASECLASS, then instead of looking for struct fields,
2021 look for a baseclass named NAME. */
2022
2023 static struct value *
2024 search_struct_field (char *name, struct value *arg1, int offset,
2025 register struct type *type, int looking_for_baseclass)
2026 {
2027 int i;
2028 int nbases = TYPE_N_BASECLASSES (type);
2029
2030 CHECK_TYPEDEF (type);
2031
2032 if (!looking_for_baseclass)
2033 for (i = TYPE_NFIELDS (type) - 1; i >= nbases; i--)
2034 {
2035 char *t_field_name = TYPE_FIELD_NAME (type, i);
2036
2037 if (t_field_name && (strcmp_iw (t_field_name, name) == 0))
2038 {
2039 struct value *v;
2040 if (TYPE_FIELD_STATIC (type, i))
2041 {
2042 v = value_static_field (type, i);
2043 if (v == 0)
2044 error ("field %s is nonexistent or has been optimised out",
2045 name);
2046 }
2047 else
2048 {
2049 v = value_primitive_field (arg1, offset, i, type);
2050 if (v == 0)
2051 error ("there is no field named %s", name);
2052 }
2053 return v;
2054 }
2055
2056 if (t_field_name
2057 && (t_field_name[0] == '\0'
2058 || (TYPE_CODE (type) == TYPE_CODE_UNION
2059 && (strcmp_iw (t_field_name, "else") == 0))))
2060 {
2061 struct type *field_type = TYPE_FIELD_TYPE (type, i);
2062 if (TYPE_CODE (field_type) == TYPE_CODE_UNION
2063 || TYPE_CODE (field_type) == TYPE_CODE_STRUCT)
2064 {
2065 /* Look for a match through the fields of an anonymous union,
2066 or anonymous struct. C++ provides anonymous unions.
2067
2068 In the GNU Chill (now deleted from GDB)
2069 implementation of variant record types, each
2070 <alternative field> has an (anonymous) union type,
2071 each member of the union represents a <variant
2072 alternative>. Each <variant alternative> is
2073 represented as a struct, with a member for each
2074 <variant field>. */
2075
2076 struct value *v;
2077 int new_offset = offset;
2078
2079 /* This is pretty gross. In G++, the offset in an
2080 anonymous union is relative to the beginning of the
2081 enclosing struct. In the GNU Chill (now deleted
2082 from GDB) implementation of variant records, the
2083 bitpos is zero in an anonymous union field, so we
2084 have to add the offset of the union here. */
2085 if (TYPE_CODE (field_type) == TYPE_CODE_STRUCT
2086 || (TYPE_NFIELDS (field_type) > 0
2087 && TYPE_FIELD_BITPOS (field_type, 0) == 0))
2088 new_offset += TYPE_FIELD_BITPOS (type, i) / 8;
2089
2090 v = search_struct_field (name, arg1, new_offset, field_type,
2091 looking_for_baseclass);
2092 if (v)
2093 return v;
2094 }
2095 }
2096 }
2097
2098 for (i = 0; i < nbases; i++)
2099 {
2100 struct value *v;
2101 struct type *basetype = check_typedef (TYPE_BASECLASS (type, i));
2102 /* If we are looking for baseclasses, this is what we get when we
2103 hit them. But it could happen that the base part's member name
2104 is not yet filled in. */
2105 int found_baseclass = (looking_for_baseclass
2106 && TYPE_BASECLASS_NAME (type, i) != NULL
2107 && (strcmp_iw (name, TYPE_BASECLASS_NAME (type, i)) == 0));
2108
2109 if (BASETYPE_VIA_VIRTUAL (type, i))
2110 {
2111 int boffset;
2112 struct value *v2 = allocate_value (basetype);
2113
2114 boffset = baseclass_offset (type, i,
2115 VALUE_CONTENTS (arg1) + offset,
2116 VALUE_ADDRESS (arg1)
2117 + VALUE_OFFSET (arg1) + offset);
2118 if (boffset == -1)
2119 error ("virtual baseclass botch");
2120
2121 /* The virtual base class pointer might have been clobbered by the
2122 user program. Make sure that it still points to a valid memory
2123 location. */
2124
2125 boffset += offset;
2126 if (boffset < 0 || boffset >= TYPE_LENGTH (type))
2127 {
2128 CORE_ADDR base_addr;
2129
2130 base_addr = VALUE_ADDRESS (arg1) + VALUE_OFFSET (arg1) + boffset;
2131 if (target_read_memory (base_addr, VALUE_CONTENTS_RAW (v2),
2132 TYPE_LENGTH (basetype)) != 0)
2133 error ("virtual baseclass botch");
2134 VALUE_LVAL (v2) = lval_memory;
2135 VALUE_ADDRESS (v2) = base_addr;
2136 }
2137 else
2138 {
2139 VALUE_LVAL (v2) = VALUE_LVAL (arg1);
2140 VALUE_ADDRESS (v2) = VALUE_ADDRESS (arg1);
2141 VALUE_OFFSET (v2) = VALUE_OFFSET (arg1) + boffset;
2142 if (VALUE_LAZY (arg1))
2143 VALUE_LAZY (v2) = 1;
2144 else
2145 memcpy (VALUE_CONTENTS_RAW (v2),
2146 VALUE_CONTENTS_RAW (arg1) + boffset,
2147 TYPE_LENGTH (basetype));
2148 }
2149
2150 if (found_baseclass)
2151 return v2;
2152 v = search_struct_field (name, v2, 0, TYPE_BASECLASS (type, i),
2153 looking_for_baseclass);
2154 }
2155 else if (found_baseclass)
2156 v = value_primitive_field (arg1, offset, i, type);
2157 else
2158 v = search_struct_field (name, arg1,
2159 offset + TYPE_BASECLASS_BITPOS (type, i) / 8,
2160 basetype, looking_for_baseclass);
2161 if (v)
2162 return v;
2163 }
2164 return NULL;
2165 }
2166
2167
2168 /* Return the offset (in bytes) of the virtual base of type BASETYPE
2169 * in an object pointed to by VALADDR (on the host), assumed to be of
2170 * type TYPE. OFFSET is number of bytes beyond start of ARG to start
2171 * looking (in case VALADDR is the contents of an enclosing object).
2172 *
2173 * This routine recurses on the primary base of the derived class because
2174 * the virtual base entries of the primary base appear before the other
2175 * virtual base entries.
2176 *
2177 * If the virtual base is not found, a negative integer is returned.
2178 * The magnitude of the negative integer is the number of entries in
2179 * the virtual table to skip over (entries corresponding to various
2180 * ancestral classes in the chain of primary bases).
2181 *
2182 * Important: This assumes the HP / Taligent C++ runtime
2183 * conventions. Use baseclass_offset() instead to deal with g++
2184 * conventions. */
2185
2186 void
2187 find_rt_vbase_offset (struct type *type, struct type *basetype, char *valaddr,
2188 int offset, int *boffset_p, int *skip_p)
2189 {
2190 int boffset; /* offset of virtual base */
2191 int index; /* displacement to use in virtual table */
2192 int skip;
2193
2194 struct value *vp;
2195 CORE_ADDR vtbl; /* the virtual table pointer */
2196 struct type *pbc; /* the primary base class */
2197
2198 /* Look for the virtual base recursively in the primary base, first.
2199 * This is because the derived class object and its primary base
2200 * subobject share the primary virtual table. */
2201
2202 boffset = 0;
2203 pbc = TYPE_PRIMARY_BASE (type);
2204 if (pbc)
2205 {
2206 find_rt_vbase_offset (pbc, basetype, valaddr, offset, &boffset, &skip);
2207 if (skip < 0)
2208 {
2209 *boffset_p = boffset;
2210 *skip_p = -1;
2211 return;
2212 }
2213 }
2214 else
2215 skip = 0;
2216
2217
2218 /* Find the index of the virtual base according to HP/Taligent
2219 runtime spec. (Depth-first, left-to-right.) */
2220 index = virtual_base_index_skip_primaries (basetype, type);
2221
2222 if (index < 0)
2223 {
2224 *skip_p = skip + virtual_base_list_length_skip_primaries (type);
2225 *boffset_p = 0;
2226 return;
2227 }
2228
2229 /* pai: FIXME -- 32x64 possible problem */
2230 /* First word (4 bytes) in object layout is the vtable pointer */
2231 vtbl = *(CORE_ADDR *) (valaddr + offset);
2232
2233 /* Before the constructor is invoked, things are usually zero'd out. */
2234 if (vtbl == 0)
2235 error ("Couldn't find virtual table -- object may not be constructed yet.");
2236
2237
2238 /* Find virtual base's offset -- jump over entries for primary base
2239 * ancestors, then use the index computed above. But also adjust by
2240 * HP_ACC_VBASE_START for the vtable slots before the start of the
2241 * virtual base entries. Offset is negative -- virtual base entries
2242 * appear _before_ the address point of the virtual table. */
2243
2244 /* pai: FIXME -- 32x64 problem, if word = 8 bytes, change multiplier
2245 & use long type */
2246
2247 /* epstein : FIXME -- added param for overlay section. May not be correct */
2248 vp = value_at (builtin_type_int, vtbl + 4 * (-skip - index - HP_ACC_VBASE_START), NULL);
2249 boffset = value_as_long (vp);
2250 *skip_p = -1;
2251 *boffset_p = boffset;
2252 return;
2253 }
2254
2255
2256 /* Helper function used by value_struct_elt to recurse through baseclasses.
2257 Look for a field NAME in ARG1. Adjust the address of ARG1 by OFFSET bytes,
2258 and search in it assuming it has (class) type TYPE.
2259 If found, return value, else if name matched and args not return (value)-1,
2260 else return NULL. */
2261
2262 static struct value *
2263 search_struct_method (char *name, struct value **arg1p,
2264 struct value **args, int offset,
2265 int *static_memfuncp, register struct type *type)
2266 {
2267 int i;
2268 struct value *v;
2269 int name_matched = 0;
2270 char dem_opname[64];
2271
2272 CHECK_TYPEDEF (type);
2273 for (i = TYPE_NFN_FIELDS (type) - 1; i >= 0; i--)
2274 {
2275 char *t_field_name = TYPE_FN_FIELDLIST_NAME (type, i);
2276 /* FIXME! May need to check for ARM demangling here */
2277 if (strncmp (t_field_name, "__", 2) == 0 ||
2278 strncmp (t_field_name, "op", 2) == 0 ||
2279 strncmp (t_field_name, "type", 4) == 0)
2280 {
2281 if (cplus_demangle_opname (t_field_name, dem_opname, DMGL_ANSI))
2282 t_field_name = dem_opname;
2283 else if (cplus_demangle_opname (t_field_name, dem_opname, 0))
2284 t_field_name = dem_opname;
2285 }
2286 if (t_field_name && (strcmp_iw (t_field_name, name) == 0))
2287 {
2288 int j = TYPE_FN_FIELDLIST_LENGTH (type, i) - 1;
2289 struct fn_field *f = TYPE_FN_FIELDLIST1 (type, i);
2290 name_matched = 1;
2291
2292 check_stub_method_group (type, i);
2293 if (j > 0 && args == 0)
2294 error ("cannot resolve overloaded method `%s': no arguments supplied", name);
2295 else if (j == 0 && args == 0)
2296 {
2297 v = value_fn_field (arg1p, f, j, type, offset);
2298 if (v != NULL)
2299 return v;
2300 }
2301 else
2302 while (j >= 0)
2303 {
2304 if (!typecmp (TYPE_FN_FIELD_STATIC_P (f, j),
2305 TYPE_VARARGS (TYPE_FN_FIELD_TYPE (f, j)),
2306 TYPE_NFIELDS (TYPE_FN_FIELD_TYPE (f, j)),
2307 TYPE_FN_FIELD_ARGS (f, j), args))
2308 {
2309 if (TYPE_FN_FIELD_VIRTUAL_P (f, j))
2310 return value_virtual_fn_field (arg1p, f, j, type, offset);
2311 if (TYPE_FN_FIELD_STATIC_P (f, j) && static_memfuncp)
2312 *static_memfuncp = 1;
2313 v = value_fn_field (arg1p, f, j, type, offset);
2314 if (v != NULL)
2315 return v;
2316 }
2317 j--;
2318 }
2319 }
2320 }
2321
2322 for (i = TYPE_N_BASECLASSES (type) - 1; i >= 0; i--)
2323 {
2324 int base_offset;
2325
2326 if (BASETYPE_VIA_VIRTUAL (type, i))
2327 {
2328 if (TYPE_HAS_VTABLE (type))
2329 {
2330 /* HP aCC compiled type, search for virtual base offset
2331 according to HP/Taligent runtime spec. */
2332 int skip;
2333 find_rt_vbase_offset (type, TYPE_BASECLASS (type, i),
2334 VALUE_CONTENTS_ALL (*arg1p),
2335 offset + VALUE_EMBEDDED_OFFSET (*arg1p),
2336 &base_offset, &skip);
2337 if (skip >= 0)
2338 error ("Virtual base class offset not found in vtable");
2339 }
2340 else
2341 {
2342 struct type *baseclass = check_typedef (TYPE_BASECLASS (type, i));
2343 char *base_valaddr;
2344
2345 /* The virtual base class pointer might have been clobbered by the
2346 user program. Make sure that it still points to a valid memory
2347 location. */
2348
2349 if (offset < 0 || offset >= TYPE_LENGTH (type))
2350 {
2351 base_valaddr = (char *) alloca (TYPE_LENGTH (baseclass));
2352 if (target_read_memory (VALUE_ADDRESS (*arg1p)
2353 + VALUE_OFFSET (*arg1p) + offset,
2354 base_valaddr,
2355 TYPE_LENGTH (baseclass)) != 0)
2356 error ("virtual baseclass botch");
2357 }
2358 else
2359 base_valaddr = VALUE_CONTENTS (*arg1p) + offset;
2360
2361 base_offset =
2362 baseclass_offset (type, i, base_valaddr,
2363 VALUE_ADDRESS (*arg1p)
2364 + VALUE_OFFSET (*arg1p) + offset);
2365 if (base_offset == -1)
2366 error ("virtual baseclass botch");
2367 }
2368 }
2369 else
2370 {
2371 base_offset = TYPE_BASECLASS_BITPOS (type, i) / 8;
2372 }
2373 v = search_struct_method (name, arg1p, args, base_offset + offset,
2374 static_memfuncp, TYPE_BASECLASS (type, i));
2375 if (v == (struct value *) - 1)
2376 {
2377 name_matched = 1;
2378 }
2379 else if (v)
2380 {
2381 /* FIXME-bothner: Why is this commented out? Why is it here? */
2382 /* *arg1p = arg1_tmp; */
2383 return v;
2384 }
2385 }
2386 if (name_matched)
2387 return (struct value *) - 1;
2388 else
2389 return NULL;
2390 }
2391
2392 /* Given *ARGP, a value of type (pointer to a)* structure/union,
2393 extract the component named NAME from the ultimate target structure/union
2394 and return it as a value with its appropriate type.
2395 ERR is used in the error message if *ARGP's type is wrong.
2396
2397 C++: ARGS is a list of argument types to aid in the selection of
2398 an appropriate method. Also, handle derived types.
2399
2400 STATIC_MEMFUNCP, if non-NULL, points to a caller-supplied location
2401 where the truthvalue of whether the function that was resolved was
2402 a static member function or not is stored.
2403
2404 ERR is an error message to be printed in case the field is not found. */
2405
2406 struct value *
2407 value_struct_elt (struct value **argp, struct value **args,
2408 char *name, int *static_memfuncp, char *err)
2409 {
2410 register struct type *t;
2411 struct value *v;
2412
2413 COERCE_ARRAY (*argp);
2414
2415 t = check_typedef (VALUE_TYPE (*argp));
2416
2417 /* Follow pointers until we get to a non-pointer. */
2418
2419 while (TYPE_CODE (t) == TYPE_CODE_PTR || TYPE_CODE (t) == TYPE_CODE_REF)
2420 {
2421 *argp = value_ind (*argp);
2422 /* Don't coerce fn pointer to fn and then back again! */
2423 if (TYPE_CODE (VALUE_TYPE (*argp)) != TYPE_CODE_FUNC)
2424 COERCE_ARRAY (*argp);
2425 t = check_typedef (VALUE_TYPE (*argp));
2426 }
2427
2428 if (TYPE_CODE (t) == TYPE_CODE_MEMBER)
2429 error ("not implemented: member type in value_struct_elt");
2430
2431 if (TYPE_CODE (t) != TYPE_CODE_STRUCT
2432 && TYPE_CODE (t) != TYPE_CODE_UNION)
2433 error ("Attempt to extract a component of a value that is not a %s.", err);
2434
2435 /* Assume it's not, unless we see that it is. */
2436 if (static_memfuncp)
2437 *static_memfuncp = 0;
2438
2439 if (!args)
2440 {
2441 /* if there are no arguments ...do this... */
2442
2443 /* Try as a field first, because if we succeed, there
2444 is less work to be done. */
2445 v = search_struct_field (name, *argp, 0, t, 0);
2446 if (v)
2447 return v;
2448
2449 /* C++: If it was not found as a data field, then try to
2450 return it as a pointer to a method. */
2451
2452 if (destructor_name_p (name, t))
2453 error ("Cannot get value of destructor");
2454
2455 v = search_struct_method (name, argp, args, 0, static_memfuncp, t);
2456
2457 if (v == (struct value *) - 1)
2458 error ("Cannot take address of a method");
2459 else if (v == 0)
2460 {
2461 if (TYPE_NFN_FIELDS (t))
2462 error ("There is no member or method named %s.", name);
2463 else
2464 error ("There is no member named %s.", name);
2465 }
2466 return v;
2467 }
2468
2469 if (destructor_name_p (name, t))
2470 {
2471 if (!args[1])
2472 {
2473 /* Destructors are a special case. */
2474 int m_index, f_index;
2475
2476 v = NULL;
2477 if (get_destructor_fn_field (t, &m_index, &f_index))
2478 {
2479 v = value_fn_field (NULL, TYPE_FN_FIELDLIST1 (t, m_index),
2480 f_index, NULL, 0);
2481 }
2482 if (v == NULL)
2483 error ("could not find destructor function named %s.", name);
2484 else
2485 return v;
2486 }
2487 else
2488 {
2489 error ("destructor should not have any argument");
2490 }
2491 }
2492 else
2493 v = search_struct_method (name, argp, args, 0, static_memfuncp, t);
2494
2495 if (v == (struct value *) - 1)
2496 {
2497 error ("One of the arguments you tried to pass to %s could not be converted to what the function wants.", name);
2498 }
2499 else if (v == 0)
2500 {
2501 /* See if user tried to invoke data as function. If so,
2502 hand it back. If it's not callable (i.e., a pointer to function),
2503 gdb should give an error. */
2504 v = search_struct_field (name, *argp, 0, t, 0);
2505 }
2506
2507 if (!v)
2508 error ("Structure has no component named %s.", name);
2509 return v;
2510 }
2511
2512 /* Search through the methods of an object (and its bases)
2513 * to find a specified method. Return the pointer to the
2514 * fn_field list of overloaded instances.
2515 * Helper function for value_find_oload_list.
2516 * ARGP is a pointer to a pointer to a value (the object)
2517 * METHOD is a string containing the method name
2518 * OFFSET is the offset within the value
2519 * TYPE is the assumed type of the object
2520 * NUM_FNS is the number of overloaded instances
2521 * BASETYPE is set to the actual type of the subobject where the method is found
2522 * BOFFSET is the offset of the base subobject where the method is found */
2523
2524 static struct fn_field *
2525 find_method_list (struct value **argp, char *method, int offset,
2526 struct type *type, int *num_fns,
2527 struct type **basetype, int *boffset)
2528 {
2529 int i;
2530 struct fn_field *f;
2531 CHECK_TYPEDEF (type);
2532
2533 *num_fns = 0;
2534
2535 /* First check in object itself */
2536 for (i = TYPE_NFN_FIELDS (type) - 1; i >= 0; i--)
2537 {
2538 /* pai: FIXME What about operators and type conversions? */
2539 char *fn_field_name = TYPE_FN_FIELDLIST_NAME (type, i);
2540 if (fn_field_name && (strcmp_iw (fn_field_name, method) == 0))
2541 {
2542 int len = TYPE_FN_FIELDLIST_LENGTH (type, i);
2543 struct fn_field *f = TYPE_FN_FIELDLIST1 (type, i);
2544
2545 *num_fns = len;
2546 *basetype = type;
2547 *boffset = offset;
2548
2549 /* Resolve any stub methods. */
2550 check_stub_method_group (type, i);
2551
2552 return f;
2553 }
2554 }
2555
2556 /* Not found in object, check in base subobjects */
2557 for (i = TYPE_N_BASECLASSES (type) - 1; i >= 0; i--)
2558 {
2559 int base_offset;
2560 if (BASETYPE_VIA_VIRTUAL (type, i))
2561 {
2562 if (TYPE_HAS_VTABLE (type))
2563 {
2564 /* HP aCC compiled type, search for virtual base offset
2565 * according to HP/Taligent runtime spec. */
2566 int skip;
2567 find_rt_vbase_offset (type, TYPE_BASECLASS (type, i),
2568 VALUE_CONTENTS_ALL (*argp),
2569 offset + VALUE_EMBEDDED_OFFSET (*argp),
2570 &base_offset, &skip);
2571 if (skip >= 0)
2572 error ("Virtual base class offset not found in vtable");
2573 }
2574 else
2575 {
2576 /* probably g++ runtime model */
2577 base_offset = VALUE_OFFSET (*argp) + offset;
2578 base_offset =
2579 baseclass_offset (type, i,
2580 VALUE_CONTENTS (*argp) + base_offset,
2581 VALUE_ADDRESS (*argp) + base_offset);
2582 if (base_offset == -1)
2583 error ("virtual baseclass botch");
2584 }
2585 }
2586 else
2587 /* non-virtual base, simply use bit position from debug info */
2588 {
2589 base_offset = TYPE_BASECLASS_BITPOS (type, i) / 8;
2590 }
2591 f = find_method_list (argp, method, base_offset + offset,
2592 TYPE_BASECLASS (type, i), num_fns, basetype,
2593 boffset);
2594 if (f)
2595 return f;
2596 }
2597 return NULL;
2598 }
2599
2600 /* Return the list of overloaded methods of a specified name.
2601 * ARGP is a pointer to a pointer to a value (the object)
2602 * METHOD is the method name
2603 * OFFSET is the offset within the value contents
2604 * NUM_FNS is the number of overloaded instances
2605 * BASETYPE is set to the type of the base subobject that defines the method
2606 * BOFFSET is the offset of the base subobject which defines the method */
2607
2608 struct fn_field *
2609 value_find_oload_method_list (struct value **argp, char *method, int offset,
2610 int *num_fns, struct type **basetype,
2611 int *boffset)
2612 {
2613 struct type *t;
2614
2615 t = check_typedef (VALUE_TYPE (*argp));
2616
2617 /* code snarfed from value_struct_elt */
2618 while (TYPE_CODE (t) == TYPE_CODE_PTR || TYPE_CODE (t) == TYPE_CODE_REF)
2619 {
2620 *argp = value_ind (*argp);
2621 /* Don't coerce fn pointer to fn and then back again! */
2622 if (TYPE_CODE (VALUE_TYPE (*argp)) != TYPE_CODE_FUNC)
2623 COERCE_ARRAY (*argp);
2624 t = check_typedef (VALUE_TYPE (*argp));
2625 }
2626
2627 if (TYPE_CODE (t) == TYPE_CODE_MEMBER)
2628 error ("Not implemented: member type in value_find_oload_lis");
2629
2630 if (TYPE_CODE (t) != TYPE_CODE_STRUCT
2631 && TYPE_CODE (t) != TYPE_CODE_UNION)
2632 error ("Attempt to extract a component of a value that is not a struct or union");
2633
2634 return find_method_list (argp, method, 0, t, num_fns, basetype, boffset);
2635 }
2636
2637 /* Given an array of argument types (ARGTYPES) (which includes an
2638 entry for "this" in the case of C++ methods), the number of
2639 arguments NARGS, the NAME of a function whether it's a method or
2640 not (METHOD), and the degree of laxness (LAX) in conforming to
2641 overload resolution rules in ANSI C++, find the best function that
2642 matches on the argument types according to the overload resolution
2643 rules.
2644
2645 In the case of class methods, the parameter OBJ is an object value
2646 in which to search for overloaded methods.
2647
2648 In the case of non-method functions, the parameter FSYM is a symbol
2649 corresponding to one of the overloaded functions.
2650
2651 Return value is an integer: 0 -> good match, 10 -> debugger applied
2652 non-standard coercions, 100 -> incompatible.
2653
2654 If a method is being searched for, VALP will hold the value.
2655 If a non-method is being searched for, SYMP will hold the symbol for it.
2656
2657 If a method is being searched for, and it is a static method,
2658 then STATICP will point to a non-zero value.
2659
2660 Note: This function does *not* check the value of
2661 overload_resolution. Caller must check it to see whether overload
2662 resolution is permitted.
2663 */
2664
2665 int
2666 find_overload_match (struct type **arg_types, int nargs, char *name, int method,
2667 int lax, struct value **objp, struct symbol *fsym,
2668 struct value **valp, struct symbol **symp, int *staticp)
2669 {
2670 int nparms;
2671 struct type **parm_types;
2672 int champ_nparms = 0;
2673 struct value *obj = (objp ? *objp : NULL);
2674
2675 short oload_champ = -1; /* Index of best overloaded function */
2676 short oload_ambiguous = 0; /* Current ambiguity state for overload resolution */
2677 /* 0 => no ambiguity, 1 => two good funcs, 2 => incomparable funcs */
2678 short oload_ambig_champ = -1; /* 2nd contender for best match */
2679 short oload_non_standard = 0; /* did we have to use non-standard conversions? */
2680 short oload_incompatible = 0; /* are args supplied incompatible with any function? */
2681
2682 struct badness_vector *bv; /* A measure of how good an overloaded instance is */
2683 struct badness_vector *oload_champ_bv = NULL; /* The measure for the current best match */
2684
2685 struct value *temp = obj;
2686 struct fn_field *fns_ptr = NULL; /* For methods, the list of overloaded methods */
2687 struct symbol **oload_syms = NULL; /* For non-methods, the list of overloaded function symbols */
2688 int num_fns = 0; /* Number of overloaded instances being considered */
2689 struct type *basetype = NULL;
2690 int boffset;
2691 register int jj;
2692 register int ix;
2693 int static_offset;
2694 struct cleanup *cleanups = NULL;
2695
2696 char *obj_type_name = NULL;
2697 char *func_name = NULL;
2698
2699 /* Get the list of overloaded methods or functions */
2700 if (method)
2701 {
2702 obj_type_name = TYPE_NAME (VALUE_TYPE (obj));
2703 /* Hack: evaluate_subexp_standard often passes in a pointer
2704 value rather than the object itself, so try again */
2705 if ((!obj_type_name || !*obj_type_name) &&
2706 (TYPE_CODE (VALUE_TYPE (obj)) == TYPE_CODE_PTR))
2707 obj_type_name = TYPE_NAME (TYPE_TARGET_TYPE (VALUE_TYPE (obj)));
2708
2709 fns_ptr = value_find_oload_method_list (&temp, name, 0,
2710 &num_fns,
2711 &basetype, &boffset);
2712 if (!fns_ptr || !num_fns)
2713 error ("Couldn't find method %s%s%s",
2714 obj_type_name,
2715 (obj_type_name && *obj_type_name) ? "::" : "",
2716 name);
2717 /* If we are dealing with stub method types, they should have
2718 been resolved by find_method_list via value_find_oload_method_list
2719 above. */
2720 gdb_assert (TYPE_DOMAIN_TYPE (fns_ptr[0].type) != NULL);
2721 }
2722 else
2723 {
2724 int i = -1;
2725 func_name = cplus_demangle (SYMBOL_NAME (fsym), DMGL_NO_OPTS);
2726
2727 /* If the name is NULL this must be a C-style function.
2728 Just return the same symbol. */
2729 if (!func_name)
2730 {
2731 *symp = fsym;
2732 return 0;
2733 }
2734
2735 oload_syms = make_symbol_overload_list (fsym);
2736 cleanups = make_cleanup (xfree, oload_syms);
2737 while (oload_syms[++i])
2738 num_fns++;
2739 if (!num_fns)
2740 error ("Couldn't find function %s", func_name);
2741 }
2742
2743 oload_champ_bv = NULL;
2744
2745 /* Consider each candidate in turn */
2746 for (ix = 0; ix < num_fns; ix++)
2747 {
2748 static_offset = 0;
2749 if (method)
2750 {
2751 if (TYPE_FN_FIELD_STATIC_P (fns_ptr, ix))
2752 static_offset = 1;
2753 nparms = TYPE_NFIELDS (TYPE_FN_FIELD_TYPE (fns_ptr, ix));
2754 }
2755 else
2756 {
2757 /* If it's not a method, this is the proper place */
2758 nparms=TYPE_NFIELDS(SYMBOL_TYPE(oload_syms[ix]));
2759 }
2760
2761 /* Prepare array of parameter types */
2762 parm_types = (struct type **) xmalloc (nparms * (sizeof (struct type *)));
2763 for (jj = 0; jj < nparms; jj++)
2764 parm_types[jj] = (method
2765 ? (TYPE_FN_FIELD_ARGS (fns_ptr, ix)[jj].type)
2766 : TYPE_FIELD_TYPE (SYMBOL_TYPE (oload_syms[ix]), jj));
2767
2768 /* Compare parameter types to supplied argument types. Skip THIS for
2769 static methods. */
2770 bv = rank_function (parm_types, nparms, arg_types + static_offset,
2771 nargs - static_offset);
2772
2773 if (!oload_champ_bv)
2774 {
2775 oload_champ_bv = bv;
2776 oload_champ = 0;
2777 champ_nparms = nparms;
2778 }
2779 else
2780 /* See whether current candidate is better or worse than previous best */
2781 switch (compare_badness (bv, oload_champ_bv))
2782 {
2783 case 0:
2784 oload_ambiguous = 1; /* top two contenders are equally good */
2785 oload_ambig_champ = ix;
2786 break;
2787 case 1:
2788 oload_ambiguous = 2; /* incomparable top contenders */
2789 oload_ambig_champ = ix;
2790 break;
2791 case 2:
2792 oload_champ_bv = bv; /* new champion, record details */
2793 oload_ambiguous = 0;
2794 oload_champ = ix;
2795 oload_ambig_champ = -1;
2796 champ_nparms = nparms;
2797 break;
2798 case 3:
2799 default:
2800 break;
2801 }
2802 xfree (parm_types);
2803 if (overload_debug)
2804 {
2805 if (method)
2806 fprintf_filtered (gdb_stderr,"Overloaded method instance %s, # of parms %d\n", fns_ptr[ix].physname, nparms);
2807 else
2808 fprintf_filtered (gdb_stderr,"Overloaded function instance %s # of parms %d\n", SYMBOL_DEMANGLED_NAME (oload_syms[ix]), nparms);
2809 for (jj = 0; jj < nargs - static_offset; jj++)
2810 fprintf_filtered (gdb_stderr,"...Badness @ %d : %d\n", jj, bv->rank[jj]);
2811 fprintf_filtered (gdb_stderr,"Overload resolution champion is %d, ambiguous? %d\n", oload_champ, oload_ambiguous);
2812 }
2813 } /* end loop over all candidates */
2814 /* NOTE: dan/2000-03-10: Seems to be a better idea to just pick one
2815 if they have the exact same goodness. This is because there is no
2816 way to differentiate based on return type, which we need to in
2817 cases like overloads of .begin() <It's both const and non-const> */
2818 #if 0
2819 if (oload_ambiguous)
2820 {
2821 if (method)
2822 error ("Cannot resolve overloaded method %s%s%s to unique instance; disambiguate by specifying function signature",
2823 obj_type_name,
2824 (obj_type_name && *obj_type_name) ? "::" : "",
2825 name);
2826 else
2827 error ("Cannot resolve overloaded function %s to unique instance; disambiguate by specifying function signature",
2828 func_name);
2829 }
2830 #endif
2831
2832 /* Check how bad the best match is. */
2833 static_offset = 0;
2834 if (method && TYPE_FN_FIELD_STATIC_P (fns_ptr, oload_champ))
2835 static_offset = 1;
2836 for (ix = 1; ix <= nargs - static_offset; ix++)
2837 {
2838 if (oload_champ_bv->rank[ix] >= 100)
2839 oload_incompatible = 1; /* truly mismatched types */
2840
2841 else if (oload_champ_bv->rank[ix] >= 10)
2842 oload_non_standard = 1; /* non-standard type conversions needed */
2843 }
2844 if (oload_incompatible)
2845 {
2846 if (method)
2847 error ("Cannot resolve method %s%s%s to any overloaded instance",
2848 obj_type_name,
2849 (obj_type_name && *obj_type_name) ? "::" : "",
2850 name);
2851 else
2852 error ("Cannot resolve function %s to any overloaded instance",
2853 func_name);
2854 }
2855 else if (oload_non_standard)
2856 {
2857 if (method)
2858 warning ("Using non-standard conversion to match method %s%s%s to supplied arguments",
2859 obj_type_name,
2860 (obj_type_name && *obj_type_name) ? "::" : "",
2861 name);
2862 else
2863 warning ("Using non-standard conversion to match function %s to supplied arguments",
2864 func_name);
2865 }
2866
2867 if (method)
2868 {
2869 if (staticp && TYPE_FN_FIELD_STATIC_P (fns_ptr, oload_champ))
2870 *staticp = 1;
2871 else if (staticp)
2872 *staticp = 0;
2873 if (TYPE_FN_FIELD_VIRTUAL_P (fns_ptr, oload_champ))
2874 *valp = value_virtual_fn_field (&temp, fns_ptr, oload_champ, basetype, boffset);
2875 else
2876 *valp = value_fn_field (&temp, fns_ptr, oload_champ, basetype, boffset);
2877 }
2878 else
2879 {
2880 *symp = oload_syms[oload_champ];
2881 xfree (func_name);
2882 }
2883
2884 if (objp)
2885 {
2886 if (TYPE_CODE (VALUE_TYPE (temp)) != TYPE_CODE_PTR
2887 && TYPE_CODE (VALUE_TYPE (*objp)) == TYPE_CODE_PTR)
2888 {
2889 temp = value_addr (temp);
2890 }
2891 *objp = temp;
2892 }
2893 if (cleanups != NULL)
2894 do_cleanups (cleanups);
2895
2896 return oload_incompatible ? 100 : (oload_non_standard ? 10 : 0);
2897 }
2898
2899 /* C++: return 1 is NAME is a legitimate name for the destructor
2900 of type TYPE. If TYPE does not have a destructor, or
2901 if NAME is inappropriate for TYPE, an error is signaled. */
2902 int
2903 destructor_name_p (const char *name, const struct type *type)
2904 {
2905 /* destructors are a special case. */
2906
2907 if (name[0] == '~')
2908 {
2909 char *dname = type_name_no_tag (type);
2910 char *cp = strchr (dname, '<');
2911 unsigned int len;
2912
2913 /* Do not compare the template part for template classes. */
2914 if (cp == NULL)
2915 len = strlen (dname);
2916 else
2917 len = cp - dname;
2918 if (strlen (name + 1) != len || !STREQN (dname, name + 1, len))
2919 error ("name of destructor must equal name of class");
2920 else
2921 return 1;
2922 }
2923 return 0;
2924 }
2925
2926 /* Helper function for check_field: Given TYPE, a structure/union,
2927 return 1 if the component named NAME from the ultimate
2928 target structure/union is defined, otherwise, return 0. */
2929
2930 static int
2931 check_field_in (register struct type *type, const char *name)
2932 {
2933 register int i;
2934
2935 for (i = TYPE_NFIELDS (type) - 1; i >= TYPE_N_BASECLASSES (type); i--)
2936 {
2937 char *t_field_name = TYPE_FIELD_NAME (type, i);
2938 if (t_field_name && (strcmp_iw (t_field_name, name) == 0))
2939 return 1;
2940 }
2941
2942 /* C++: If it was not found as a data field, then try to
2943 return it as a pointer to a method. */
2944
2945 /* Destructors are a special case. */
2946 if (destructor_name_p (name, type))
2947 {
2948 int m_index, f_index;
2949
2950 return get_destructor_fn_field (type, &m_index, &f_index);
2951 }
2952
2953 for (i = TYPE_NFN_FIELDS (type) - 1; i >= 0; --i)
2954 {
2955 if (strcmp_iw (TYPE_FN_FIELDLIST_NAME (type, i), name) == 0)
2956 return 1;
2957 }
2958
2959 for (i = TYPE_N_BASECLASSES (type) - 1; i >= 0; i--)
2960 if (check_field_in (TYPE_BASECLASS (type, i), name))
2961 return 1;
2962
2963 return 0;
2964 }
2965
2966
2967 /* C++: Given ARG1, a value of type (pointer to a)* structure/union,
2968 return 1 if the component named NAME from the ultimate
2969 target structure/union is defined, otherwise, return 0. */
2970
2971 int
2972 check_field (struct value *arg1, const char *name)
2973 {
2974 register struct type *t;
2975
2976 COERCE_ARRAY (arg1);
2977
2978 t = VALUE_TYPE (arg1);
2979
2980 /* Follow pointers until we get to a non-pointer. */
2981
2982 for (;;)
2983 {
2984 CHECK_TYPEDEF (t);
2985 if (TYPE_CODE (t) != TYPE_CODE_PTR && TYPE_CODE (t) != TYPE_CODE_REF)
2986 break;
2987 t = TYPE_TARGET_TYPE (t);
2988 }
2989
2990 if (TYPE_CODE (t) == TYPE_CODE_MEMBER)
2991 error ("not implemented: member type in check_field");
2992
2993 if (TYPE_CODE (t) != TYPE_CODE_STRUCT
2994 && TYPE_CODE (t) != TYPE_CODE_UNION)
2995 error ("Internal error: `this' is not an aggregate");
2996
2997 return check_field_in (t, name);
2998 }
2999
3000 /* C++: Given an aggregate type CURTYPE, and a member name NAME,
3001 return the address of this member as a "pointer to member"
3002 type. If INTYPE is non-null, then it will be the type
3003 of the member we are looking for. This will help us resolve
3004 "pointers to member functions". This function is used
3005 to resolve user expressions of the form "DOMAIN::NAME". */
3006
3007 struct value *
3008 value_struct_elt_for_reference (struct type *domain, int offset,
3009 struct type *curtype, char *name,
3010 struct type *intype)
3011 {
3012 register struct type *t = curtype;
3013 register int i;
3014 struct value *v;
3015
3016 if (TYPE_CODE (t) != TYPE_CODE_STRUCT
3017 && TYPE_CODE (t) != TYPE_CODE_UNION)
3018 error ("Internal error: non-aggregate type to value_struct_elt_for_reference");
3019
3020 for (i = TYPE_NFIELDS (t) - 1; i >= TYPE_N_BASECLASSES (t); i--)
3021 {
3022 char *t_field_name = TYPE_FIELD_NAME (t, i);
3023
3024 if (t_field_name && STREQ (t_field_name, name))
3025 {
3026 if (TYPE_FIELD_STATIC (t, i))
3027 {
3028 v = value_static_field (t, i);
3029 if (v == NULL)
3030 error ("static field %s has been optimized out",
3031 name);
3032 return v;
3033 }
3034 if (TYPE_FIELD_PACKED (t, i))
3035 error ("pointers to bitfield members not allowed");
3036
3037 return value_from_longest
3038 (lookup_reference_type (lookup_member_type (TYPE_FIELD_TYPE (t, i),
3039 domain)),
3040 offset + (LONGEST) (TYPE_FIELD_BITPOS (t, i) >> 3));
3041 }
3042 }
3043
3044 /* C++: If it was not found as a data field, then try to
3045 return it as a pointer to a method. */
3046
3047 /* Destructors are a special case. */
3048 if (destructor_name_p (name, t))
3049 {
3050 error ("member pointers to destructors not implemented yet");
3051 }
3052
3053 /* Perform all necessary dereferencing. */
3054 while (intype && TYPE_CODE (intype) == TYPE_CODE_PTR)
3055 intype = TYPE_TARGET_TYPE (intype);
3056
3057 for (i = TYPE_NFN_FIELDS (t) - 1; i >= 0; --i)
3058 {
3059 char *t_field_name = TYPE_FN_FIELDLIST_NAME (t, i);
3060 char dem_opname[64];
3061
3062 if (strncmp (t_field_name, "__", 2) == 0 ||
3063 strncmp (t_field_name, "op", 2) == 0 ||
3064 strncmp (t_field_name, "type", 4) == 0)
3065 {
3066 if (cplus_demangle_opname (t_field_name, dem_opname, DMGL_ANSI))
3067 t_field_name = dem_opname;
3068 else if (cplus_demangle_opname (t_field_name, dem_opname, 0))
3069 t_field_name = dem_opname;
3070 }
3071 if (t_field_name && STREQ (t_field_name, name))
3072 {
3073 int j = TYPE_FN_FIELDLIST_LENGTH (t, i);
3074 struct fn_field *f = TYPE_FN_FIELDLIST1 (t, i);
3075
3076 check_stub_method_group (t, i);
3077
3078 if (intype == 0 && j > 1)
3079 error ("non-unique member `%s' requires type instantiation", name);
3080 if (intype)
3081 {
3082 while (j--)
3083 if (TYPE_FN_FIELD_TYPE (f, j) == intype)
3084 break;
3085 if (j < 0)
3086 error ("no member function matches that type instantiation");
3087 }
3088 else
3089 j = 0;
3090
3091 if (TYPE_FN_FIELD_VIRTUAL_P (f, j))
3092 {
3093 return value_from_longest
3094 (lookup_reference_type
3095 (lookup_member_type (TYPE_FN_FIELD_TYPE (f, j),
3096 domain)),
3097 (LONGEST) METHOD_PTR_FROM_VOFFSET (TYPE_FN_FIELD_VOFFSET (f, j)));
3098 }
3099 else
3100 {
3101 struct symbol *s = lookup_symbol (TYPE_FN_FIELD_PHYSNAME (f, j),
3102 0, VAR_NAMESPACE, 0, NULL);
3103 if (s == NULL)
3104 {
3105 v = 0;
3106 }
3107 else
3108 {
3109 v = read_var_value (s, 0);
3110 #if 0
3111 VALUE_TYPE (v) = lookup_reference_type
3112 (lookup_member_type (TYPE_FN_FIELD_TYPE (f, j),
3113 domain));
3114 #endif
3115 }
3116 return v;
3117 }
3118 }
3119 }
3120 for (i = TYPE_N_BASECLASSES (t) - 1; i >= 0; i--)
3121 {
3122 struct value *v;
3123 int base_offset;
3124
3125 if (BASETYPE_VIA_VIRTUAL (t, i))
3126 base_offset = 0;
3127 else
3128 base_offset = TYPE_BASECLASS_BITPOS (t, i) / 8;
3129 v = value_struct_elt_for_reference (domain,
3130 offset + base_offset,
3131 TYPE_BASECLASS (t, i),
3132 name,
3133 intype);
3134 if (v)
3135 return v;
3136 }
3137 return 0;
3138 }
3139
3140
3141 /* Given a pointer value V, find the real (RTTI) type
3142 of the object it points to.
3143 Other parameters FULL, TOP, USING_ENC as with value_rtti_type()
3144 and refer to the values computed for the object pointed to. */
3145
3146 struct type *
3147 value_rtti_target_type (struct value *v, int *full, int *top, int *using_enc)
3148 {
3149 struct value *target;
3150
3151 target = value_ind (v);
3152
3153 return value_rtti_type (target, full, top, using_enc);
3154 }
3155
3156 /* Given a value pointed to by ARGP, check its real run-time type, and
3157 if that is different from the enclosing type, create a new value
3158 using the real run-time type as the enclosing type (and of the same
3159 type as ARGP) and return it, with the embedded offset adjusted to
3160 be the correct offset to the enclosed object
3161 RTYPE is the type, and XFULL, XTOP, and XUSING_ENC are the other
3162 parameters, computed by value_rtti_type(). If these are available,
3163 they can be supplied and a second call to value_rtti_type() is avoided.
3164 (Pass RTYPE == NULL if they're not available */
3165
3166 struct value *
3167 value_full_object (struct value *argp, struct type *rtype, int xfull, int xtop,
3168 int xusing_enc)
3169 {
3170 struct type *real_type;
3171 int full = 0;
3172 int top = -1;
3173 int using_enc = 0;
3174 struct value *new_val;
3175
3176 if (rtype)
3177 {
3178 real_type = rtype;
3179 full = xfull;
3180 top = xtop;
3181 using_enc = xusing_enc;
3182 }
3183 else
3184 real_type = value_rtti_type (argp, &full, &top, &using_enc);
3185
3186 /* If no RTTI data, or if object is already complete, do nothing */
3187 if (!real_type || real_type == VALUE_ENCLOSING_TYPE (argp))
3188 return argp;
3189
3190 /* If we have the full object, but for some reason the enclosing
3191 type is wrong, set it *//* pai: FIXME -- sounds iffy */
3192 if (full)
3193 {
3194 argp = value_change_enclosing_type (argp, real_type);
3195 return argp;
3196 }
3197
3198 /* Check if object is in memory */
3199 if (VALUE_LVAL (argp) != lval_memory)
3200 {
3201 warning ("Couldn't retrieve complete object of RTTI type %s; object may be in register(s).", TYPE_NAME (real_type));
3202
3203 return argp;
3204 }
3205
3206 /* All other cases -- retrieve the complete object */
3207 /* Go back by the computed top_offset from the beginning of the object,
3208 adjusting for the embedded offset of argp if that's what value_rtti_type
3209 used for its computation. */
3210 new_val = value_at_lazy (real_type, VALUE_ADDRESS (argp) - top +
3211 (using_enc ? 0 : VALUE_EMBEDDED_OFFSET (argp)),
3212 VALUE_BFD_SECTION (argp));
3213 VALUE_TYPE (new_val) = VALUE_TYPE (argp);
3214 VALUE_EMBEDDED_OFFSET (new_val) = using_enc ? top + VALUE_EMBEDDED_OFFSET (argp) : top;
3215 return new_val;
3216 }
3217
3218
3219
3220
3221 /* Return the value of the local variable, if one exists.
3222 Flag COMPLAIN signals an error if the request is made in an
3223 inappropriate context. */
3224
3225 struct value *
3226 value_of_local (const char *name, int complain)
3227 {
3228 struct symbol *func, *sym;
3229 struct block *b;
3230 int i;
3231 struct value * ret;
3232
3233 if (deprecated_selected_frame == 0)
3234 {
3235 if (complain)
3236 error ("no frame selected");
3237 else
3238 return 0;
3239 }
3240
3241 func = get_frame_function (deprecated_selected_frame);
3242 if (!func)
3243 {
3244 if (complain)
3245 error ("no `%s' in nameless context", name);
3246 else
3247 return 0;
3248 }
3249
3250 b = SYMBOL_BLOCK_VALUE (func);
3251 i = BLOCK_NSYMS (b);
3252 if (i <= 0)
3253 {
3254 if (complain)
3255 error ("no args, no `%s'", name);
3256 else
3257 return 0;
3258 }
3259
3260 /* Calling lookup_block_symbol is necessary to get the LOC_REGISTER
3261 symbol instead of the LOC_ARG one (if both exist). */
3262 sym = lookup_block_symbol (b, name, NULL, VAR_NAMESPACE);
3263 if (sym == NULL)
3264 {
3265 if (complain)
3266 error ("current stack frame does not contain a variable named `%s'", name);
3267 else
3268 return NULL;
3269 }
3270
3271 ret = read_var_value (sym, deprecated_selected_frame);
3272 if (ret == 0 && complain)
3273 error ("`%s' argument unreadable", name);
3274 return ret;
3275 }
3276
3277 /* C++/Objective-C: return the value of the class instance variable,
3278 if one exists. Flag COMPLAIN signals an error if the request is
3279 made in an inappropriate context. */
3280
3281 struct value *
3282 value_of_this (int complain)
3283 {
3284 if (current_language->la_language == language_objc)
3285 return value_of_local ("self", complain);
3286 else
3287 return value_of_local ("this", complain);
3288 }
3289
3290 /* Create a slice (sub-string, sub-array) of ARRAY, that is LENGTH elements
3291 long, starting at LOWBOUND. The result has the same lower bound as
3292 the original ARRAY. */
3293
3294 struct value *
3295 value_slice (struct value *array, int lowbound, int length)
3296 {
3297 struct type *slice_range_type, *slice_type, *range_type;
3298 LONGEST lowerbound, upperbound;
3299 struct value *slice;
3300 struct type *array_type;
3301 array_type = check_typedef (VALUE_TYPE (array));
3302 COERCE_VARYING_ARRAY (array, array_type);
3303 if (TYPE_CODE (array_type) != TYPE_CODE_ARRAY
3304 && TYPE_CODE (array_type) != TYPE_CODE_STRING
3305 && TYPE_CODE (array_type) != TYPE_CODE_BITSTRING)
3306 error ("cannot take slice of non-array");
3307 range_type = TYPE_INDEX_TYPE (array_type);
3308 if (get_discrete_bounds (range_type, &lowerbound, &upperbound) < 0)
3309 error ("slice from bad array or bitstring");
3310 if (lowbound < lowerbound || length < 0
3311 || lowbound + length - 1 > upperbound)
3312 error ("slice out of range");
3313 /* FIXME-type-allocation: need a way to free this type when we are
3314 done with it. */
3315 slice_range_type = create_range_type ((struct type *) NULL,
3316 TYPE_TARGET_TYPE (range_type),
3317 lowbound, lowbound + length - 1);
3318 if (TYPE_CODE (array_type) == TYPE_CODE_BITSTRING)
3319 {
3320 int i;
3321 slice_type = create_set_type ((struct type *) NULL, slice_range_type);
3322 TYPE_CODE (slice_type) = TYPE_CODE_BITSTRING;
3323 slice = value_zero (slice_type, not_lval);
3324 for (i = 0; i < length; i++)
3325 {
3326 int element = value_bit_index (array_type,
3327 VALUE_CONTENTS (array),
3328 lowbound + i);
3329 if (element < 0)
3330 error ("internal error accessing bitstring");
3331 else if (element > 0)
3332 {
3333 int j = i % TARGET_CHAR_BIT;
3334 if (BITS_BIG_ENDIAN)
3335 j = TARGET_CHAR_BIT - 1 - j;
3336 VALUE_CONTENTS_RAW (slice)[i / TARGET_CHAR_BIT] |= (1 << j);
3337 }
3338 }
3339 /* We should set the address, bitssize, and bitspos, so the clice
3340 can be used on the LHS, but that may require extensions to
3341 value_assign. For now, just leave as a non_lval. FIXME. */
3342 }
3343 else
3344 {
3345 struct type *element_type = TYPE_TARGET_TYPE (array_type);
3346 LONGEST offset
3347 = (lowbound - lowerbound) * TYPE_LENGTH (check_typedef (element_type));
3348 slice_type = create_array_type ((struct type *) NULL, element_type,
3349 slice_range_type);
3350 TYPE_CODE (slice_type) = TYPE_CODE (array_type);
3351 slice = allocate_value (slice_type);
3352 if (VALUE_LAZY (array))
3353 VALUE_LAZY (slice) = 1;
3354 else
3355 memcpy (VALUE_CONTENTS (slice), VALUE_CONTENTS (array) + offset,
3356 TYPE_LENGTH (slice_type));
3357 if (VALUE_LVAL (array) == lval_internalvar)
3358 VALUE_LVAL (slice) = lval_internalvar_component;
3359 else
3360 VALUE_LVAL (slice) = VALUE_LVAL (array);
3361 VALUE_ADDRESS (slice) = VALUE_ADDRESS (array);
3362 VALUE_OFFSET (slice) = VALUE_OFFSET (array) + offset;
3363 }
3364 return slice;
3365 }
3366
3367 /* Create a value for a FORTRAN complex number. Currently most of
3368 the time values are coerced to COMPLEX*16 (i.e. a complex number
3369 composed of 2 doubles. This really should be a smarter routine
3370 that figures out precision inteligently as opposed to assuming
3371 doubles. FIXME: fmb */
3372
3373 struct value *
3374 value_literal_complex (struct value *arg1, struct value *arg2, struct type *type)
3375 {
3376 struct value *val;
3377 struct type *real_type = TYPE_TARGET_TYPE (type);
3378
3379 val = allocate_value (type);
3380 arg1 = value_cast (real_type, arg1);
3381 arg2 = value_cast (real_type, arg2);
3382
3383 memcpy (VALUE_CONTENTS_RAW (val),
3384 VALUE_CONTENTS (arg1), TYPE_LENGTH (real_type));
3385 memcpy (VALUE_CONTENTS_RAW (val) + TYPE_LENGTH (real_type),
3386 VALUE_CONTENTS (arg2), TYPE_LENGTH (real_type));
3387 return val;
3388 }
3389
3390 /* Cast a value into the appropriate complex data type. */
3391
3392 static struct value *
3393 cast_into_complex (struct type *type, struct value *val)
3394 {
3395 struct type *real_type = TYPE_TARGET_TYPE (type);
3396 if (TYPE_CODE (VALUE_TYPE (val)) == TYPE_CODE_COMPLEX)
3397 {
3398 struct type *val_real_type = TYPE_TARGET_TYPE (VALUE_TYPE (val));
3399 struct value *re_val = allocate_value (val_real_type);
3400 struct value *im_val = allocate_value (val_real_type);
3401
3402 memcpy (VALUE_CONTENTS_RAW (re_val),
3403 VALUE_CONTENTS (val), TYPE_LENGTH (val_real_type));
3404 memcpy (VALUE_CONTENTS_RAW (im_val),
3405 VALUE_CONTENTS (val) + TYPE_LENGTH (val_real_type),
3406 TYPE_LENGTH (val_real_type));
3407
3408 return value_literal_complex (re_val, im_val, type);
3409 }
3410 else if (TYPE_CODE (VALUE_TYPE (val)) == TYPE_CODE_FLT
3411 || TYPE_CODE (VALUE_TYPE (val)) == TYPE_CODE_INT)
3412 return value_literal_complex (val, value_zero (real_type, not_lval), type);
3413 else
3414 error ("cannot cast non-number to complex");
3415 }
3416
3417 void
3418 _initialize_valops (void)
3419 {
3420 #if 0
3421 add_show_from_set
3422 (add_set_cmd ("abandon", class_support, var_boolean, (char *) &auto_abandon,
3423 "Set automatic abandonment of expressions upon failure.",
3424 &setlist),
3425 &showlist);
3426 #endif
3427
3428 add_show_from_set
3429 (add_set_cmd ("overload-resolution", class_support, var_boolean, (char *) &overload_resolution,
3430 "Set overload resolution in evaluating C++ functions.",
3431 &setlist),
3432 &showlist);
3433 overload_resolution = 1;
3434
3435 add_show_from_set (
3436 add_set_cmd ("unwindonsignal", no_class, var_boolean,
3437 (char *) &unwind_on_signal_p,
3438 "Set unwinding of stack if a signal is received while in a call dummy.\n\
3439 The unwindonsignal lets the user determine what gdb should do if a signal\n\
3440 is received while in a function called from gdb (call dummy). If set, gdb\n\
3441 unwinds the stack and restore the context to what as it was before the call.\n\
3442 The default is to stop in the frame where the signal was received.", &setlist),
3443 &showlist);
3444
3445 add_show_from_set
3446 (add_set_cmd ("coerce-float-to-double", class_obscure, var_boolean,
3447 (char *) &coerce_float_to_double,
3448 "Set coercion of floats to doubles when calling functions\n"
3449 "Variables of type float should generally be converted to doubles before\n"
3450 "calling an unprototyped function, and left alone when calling a prototyped\n"
3451 "function. However, some older debug info formats do not provide enough\n"
3452 "information to determine that a function is prototyped. If this flag is\n"
3453 "set, GDB will perform the conversion for a function it considers\n"
3454 "unprototyped.\n"
3455 "The default is to perform the conversion.\n",
3456 &setlist),
3457 &showlist);
3458 coerce_float_to_double = 1;
3459 }
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