* hppa-tdep.c (_initialize_hppa_tdep): Add declaration.
[binutils-gdb.git] / gdb / valops.c
blob5907d96116ca2bb2a6a85d6b0370190aa705a1e7
1 /* Perform non-arithmetic operations on values, for GDB.
3 Copyright (C) 1986, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995,
4 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007,
5 2008, 2009 Free Software Foundation, Inc.
7 This file is part of GDB.
9 This program is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 3 of the License, or
12 (at your option) any later version.
14 This program is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
19 You should have received a copy of the GNU General Public License
20 along with this program. If not, see <http://www.gnu.org/licenses/>. */
22 #include "defs.h"
23 #include "symtab.h"
24 #include "gdbtypes.h"
25 #include "value.h"
26 #include "frame.h"
27 #include "inferior.h"
28 #include "gdbcore.h"
29 #include "target.h"
30 #include "demangle.h"
31 #include "language.h"
32 #include "gdbcmd.h"
33 #include "regcache.h"
34 #include "cp-abi.h"
35 #include "block.h"
36 #include "infcall.h"
37 #include "dictionary.h"
38 #include "cp-support.h"
39 #include "dfp.h"
40 #include "user-regs.h"
42 #include <errno.h>
43 #include "gdb_string.h"
44 #include "gdb_assert.h"
45 #include "cp-support.h"
46 #include "observer.h"
47 #include "objfiles.h"
48 #include "symtab.h"
50 extern int overload_debug;
51 /* Local functions. */
53 static int typecmp (int staticp, int varargs, int nargs,
54 struct field t1[], struct value *t2[]);
56 static struct value *search_struct_field (char *, struct value *,
57 int, struct type *, int);
59 static struct value *search_struct_method (char *, struct value **,
60 struct value **,
61 int, int *, struct type *);
63 static int find_oload_champ_namespace (struct type **, int,
64 const char *, const char *,
65 struct symbol ***,
66 struct badness_vector **);
68 static
69 int find_oload_champ_namespace_loop (struct type **, int,
70 const char *, const char *,
71 int, struct symbol ***,
72 struct badness_vector **, int *);
74 static int find_oload_champ (struct type **, int, int, int,
75 struct fn_field *, struct symbol **,
76 struct badness_vector **);
78 static int oload_method_static (int, struct fn_field *, int);
80 enum oload_classification { STANDARD, NON_STANDARD, INCOMPATIBLE };
82 static enum
83 oload_classification classify_oload_match (struct badness_vector *,
84 int, int);
86 static struct value *value_struct_elt_for_reference (struct type *,
87 int, struct type *,
88 char *,
89 struct type *,
90 int, enum noside);
92 static struct value *value_namespace_elt (const struct type *,
93 char *, int , enum noside);
95 static struct value *value_maybe_namespace_elt (const struct type *,
96 char *, int,
97 enum noside);
99 static CORE_ADDR allocate_space_in_inferior (int);
101 static struct value *cast_into_complex (struct type *, struct value *);
103 static struct fn_field *find_method_list (struct value **, char *,
104 int, struct type *, int *,
105 struct type **, int *);
107 void _initialize_valops (void);
109 #if 0
110 /* Flag for whether we want to abandon failed expression evals by
111 default. */
113 static int auto_abandon = 0;
114 #endif
116 int overload_resolution = 0;
117 static void
118 show_overload_resolution (struct ui_file *file, int from_tty,
119 struct cmd_list_element *c,
120 const char *value)
122 fprintf_filtered (file, _("\
123 Overload resolution in evaluating C++ functions is %s.\n"),
124 value);
127 /* Find the address of function name NAME in the inferior. If OBJF_P
128 is non-NULL, *OBJF_P will be set to the OBJFILE where the function
129 is defined. */
131 struct value *
132 find_function_in_inferior (const char *name, struct objfile **objf_p)
134 struct symbol *sym;
135 sym = lookup_symbol (name, 0, VAR_DOMAIN, 0);
136 if (sym != NULL)
138 if (SYMBOL_CLASS (sym) != LOC_BLOCK)
140 error (_("\"%s\" exists in this program but is not a function."),
141 name);
144 if (objf_p)
145 *objf_p = SYMBOL_SYMTAB (sym)->objfile;
147 return value_of_variable (sym, NULL);
149 else
151 struct minimal_symbol *msymbol =
152 lookup_minimal_symbol (name, NULL, NULL);
153 if (msymbol != NULL)
155 struct objfile *objfile = msymbol_objfile (msymbol);
156 struct gdbarch *gdbarch = get_objfile_arch (objfile);
158 struct type *type;
159 CORE_ADDR maddr;
160 type = lookup_pointer_type (builtin_type (gdbarch)->builtin_char);
161 type = lookup_function_type (type);
162 type = lookup_pointer_type (type);
163 maddr = SYMBOL_VALUE_ADDRESS (msymbol);
165 if (objf_p)
166 *objf_p = objfile;
168 return value_from_pointer (type, maddr);
170 else
172 if (!target_has_execution)
173 error (_("evaluation of this expression requires the target program to be active"));
174 else
175 error (_("evaluation of this expression requires the program to have a function \"%s\"."), name);
180 /* Allocate NBYTES of space in the inferior using the inferior's
181 malloc and return a value that is a pointer to the allocated
182 space. */
184 struct value *
185 value_allocate_space_in_inferior (int len)
187 struct objfile *objf;
188 struct value *val = find_function_in_inferior ("malloc", &objf);
189 struct gdbarch *gdbarch = get_objfile_arch (objf);
190 struct value *blocklen;
192 blocklen = value_from_longest (builtin_type (gdbarch)->builtin_int, len);
193 val = call_function_by_hand (val, 1, &blocklen);
194 if (value_logical_not (val))
196 if (!target_has_execution)
197 error (_("No memory available to program now: you need to start the target first"));
198 else
199 error (_("No memory available to program: call to malloc failed"));
201 return val;
204 static CORE_ADDR
205 allocate_space_in_inferior (int len)
207 return value_as_long (value_allocate_space_in_inferior (len));
210 /* Cast struct value VAL to type TYPE and return as a value.
211 Both type and val must be of TYPE_CODE_STRUCT or TYPE_CODE_UNION
212 for this to work. Typedef to one of the codes is permitted.
213 Returns NULL if the cast is neither an upcast nor a downcast. */
215 static struct value *
216 value_cast_structs (struct type *type, struct value *v2)
218 struct type *t1;
219 struct type *t2;
220 struct value *v;
222 gdb_assert (type != NULL && v2 != NULL);
224 t1 = check_typedef (type);
225 t2 = check_typedef (value_type (v2));
227 /* Check preconditions. */
228 gdb_assert ((TYPE_CODE (t1) == TYPE_CODE_STRUCT
229 || TYPE_CODE (t1) == TYPE_CODE_UNION)
230 && !!"Precondition is that type is of STRUCT or UNION kind.");
231 gdb_assert ((TYPE_CODE (t2) == TYPE_CODE_STRUCT
232 || TYPE_CODE (t2) == TYPE_CODE_UNION)
233 && !!"Precondition is that value is of STRUCT or UNION kind");
235 /* Upcasting: look in the type of the source to see if it contains the
236 type of the target as a superclass. If so, we'll need to
237 offset the pointer rather than just change its type. */
238 if (TYPE_NAME (t1) != NULL)
240 v = search_struct_field (type_name_no_tag (t1),
241 v2, 0, t2, 1);
242 if (v)
243 return v;
246 /* Downcasting: look in the type of the target to see if it contains the
247 type of the source as a superclass. If so, we'll need to
248 offset the pointer rather than just change its type.
249 FIXME: This fails silently with virtual inheritance. */
250 if (TYPE_NAME (t2) != NULL)
252 v = search_struct_field (type_name_no_tag (t2),
253 value_zero (t1, not_lval), 0, t1, 1);
254 if (v)
256 /* Downcasting is possible (t1 is superclass of v2). */
257 CORE_ADDR addr2 = value_address (v2);
258 addr2 -= value_address (v) + value_embedded_offset (v);
259 return value_at (type, addr2);
263 return NULL;
266 /* Cast one pointer or reference type to another. Both TYPE and
267 the type of ARG2 should be pointer types, or else both should be
268 reference types. Returns the new pointer or reference. */
270 struct value *
271 value_cast_pointers (struct type *type, struct value *arg2)
273 struct type *type1 = check_typedef (type);
274 struct type *type2 = check_typedef (value_type (arg2));
275 struct type *t1 = check_typedef (TYPE_TARGET_TYPE (type));
276 struct type *t2 = check_typedef (TYPE_TARGET_TYPE (type2));
278 if (TYPE_CODE (t1) == TYPE_CODE_STRUCT
279 && TYPE_CODE (t2) == TYPE_CODE_STRUCT
280 && !value_logical_not (arg2))
282 struct value *v2;
284 if (TYPE_CODE (type2) == TYPE_CODE_REF)
285 v2 = coerce_ref (arg2);
286 else
287 v2 = value_ind (arg2);
288 gdb_assert (TYPE_CODE (check_typedef (value_type (v2))) == TYPE_CODE_STRUCT
289 && !!"Why did coercion fail?");
290 v2 = value_cast_structs (t1, v2);
291 /* At this point we have what we can have, un-dereference if needed. */
292 if (v2)
294 struct value *v = value_addr (v2);
295 deprecated_set_value_type (v, type);
296 return v;
300 /* No superclass found, just change the pointer type. */
301 arg2 = value_copy (arg2);
302 deprecated_set_value_type (arg2, type);
303 arg2 = value_change_enclosing_type (arg2, type);
304 set_value_pointed_to_offset (arg2, 0); /* pai: chk_val */
305 return arg2;
308 /* Cast value ARG2 to type TYPE and return as a value.
309 More general than a C cast: accepts any two types of the same length,
310 and if ARG2 is an lvalue it can be cast into anything at all. */
311 /* In C++, casts may change pointer or object representations. */
313 struct value *
314 value_cast (struct type *type, struct value *arg2)
316 enum type_code code1;
317 enum type_code code2;
318 int scalar;
319 struct type *type2;
321 int convert_to_boolean = 0;
323 if (value_type (arg2) == type)
324 return arg2;
326 code1 = TYPE_CODE (check_typedef (type));
328 /* Check if we are casting struct reference to struct reference. */
329 if (code1 == TYPE_CODE_REF)
331 /* We dereference type; then we recurse and finally
332 we generate value of the given reference. Nothing wrong with
333 that. */
334 struct type *t1 = check_typedef (type);
335 struct type *dereftype = check_typedef (TYPE_TARGET_TYPE (t1));
336 struct value *val = value_cast (dereftype, arg2);
337 return value_ref (val);
340 code2 = TYPE_CODE (check_typedef (value_type (arg2)));
342 if (code2 == TYPE_CODE_REF)
343 /* We deref the value and then do the cast. */
344 return value_cast (type, coerce_ref (arg2));
346 CHECK_TYPEDEF (type);
347 code1 = TYPE_CODE (type);
348 arg2 = coerce_ref (arg2);
349 type2 = check_typedef (value_type (arg2));
351 /* You can't cast to a reference type. See value_cast_pointers
352 instead. */
353 gdb_assert (code1 != TYPE_CODE_REF);
355 /* A cast to an undetermined-length array_type, such as
356 (TYPE [])OBJECT, is treated like a cast to (TYPE [N])OBJECT,
357 where N is sizeof(OBJECT)/sizeof(TYPE). */
358 if (code1 == TYPE_CODE_ARRAY)
360 struct type *element_type = TYPE_TARGET_TYPE (type);
361 unsigned element_length = TYPE_LENGTH (check_typedef (element_type));
362 if (element_length > 0 && TYPE_ARRAY_UPPER_BOUND_IS_UNDEFINED (type))
364 struct type *range_type = TYPE_INDEX_TYPE (type);
365 int val_length = TYPE_LENGTH (type2);
366 LONGEST low_bound, high_bound, new_length;
367 if (get_discrete_bounds (range_type, &low_bound, &high_bound) < 0)
368 low_bound = 0, high_bound = 0;
369 new_length = val_length / element_length;
370 if (val_length % element_length != 0)
371 warning (_("array element type size does not divide object size in cast"));
372 /* FIXME-type-allocation: need a way to free this type when
373 we are done with it. */
374 range_type = create_range_type ((struct type *) NULL,
375 TYPE_TARGET_TYPE (range_type),
376 low_bound,
377 new_length + low_bound - 1);
378 deprecated_set_value_type (arg2,
379 create_array_type ((struct type *) NULL,
380 element_type,
381 range_type));
382 return arg2;
386 if (current_language->c_style_arrays
387 && TYPE_CODE (type2) == TYPE_CODE_ARRAY)
388 arg2 = value_coerce_array (arg2);
390 if (TYPE_CODE (type2) == TYPE_CODE_FUNC)
391 arg2 = value_coerce_function (arg2);
393 type2 = check_typedef (value_type (arg2));
394 code2 = TYPE_CODE (type2);
396 if (code1 == TYPE_CODE_COMPLEX)
397 return cast_into_complex (type, arg2);
398 if (code1 == TYPE_CODE_BOOL)
400 code1 = TYPE_CODE_INT;
401 convert_to_boolean = 1;
403 if (code1 == TYPE_CODE_CHAR)
404 code1 = TYPE_CODE_INT;
405 if (code2 == TYPE_CODE_BOOL || code2 == TYPE_CODE_CHAR)
406 code2 = TYPE_CODE_INT;
408 scalar = (code2 == TYPE_CODE_INT || code2 == TYPE_CODE_FLT
409 || code2 == TYPE_CODE_DECFLOAT || code2 == TYPE_CODE_ENUM
410 || code2 == TYPE_CODE_RANGE);
412 if ((code1 == TYPE_CODE_STRUCT || code1 == TYPE_CODE_UNION)
413 && (code2 == TYPE_CODE_STRUCT || code2 == TYPE_CODE_UNION)
414 && TYPE_NAME (type) != 0)
416 struct value *v = value_cast_structs (type, arg2);
417 if (v)
418 return v;
421 if (code1 == TYPE_CODE_FLT && scalar)
422 return value_from_double (type, value_as_double (arg2));
423 else if (code1 == TYPE_CODE_DECFLOAT && scalar)
425 int dec_len = TYPE_LENGTH (type);
426 gdb_byte dec[16];
428 if (code2 == TYPE_CODE_FLT)
429 decimal_from_floating (arg2, dec, dec_len);
430 else if (code2 == TYPE_CODE_DECFLOAT)
431 decimal_convert (value_contents (arg2), TYPE_LENGTH (type2),
432 dec, dec_len);
433 else
434 /* The only option left is an integral type. */
435 decimal_from_integral (arg2, dec, dec_len);
437 return value_from_decfloat (type, dec);
439 else if ((code1 == TYPE_CODE_INT || code1 == TYPE_CODE_ENUM
440 || code1 == TYPE_CODE_RANGE)
441 && (scalar || code2 == TYPE_CODE_PTR
442 || code2 == TYPE_CODE_MEMBERPTR))
444 LONGEST longest;
446 /* When we cast pointers to integers, we mustn't use
447 gdbarch_pointer_to_address to find the address the pointer
448 represents, as value_as_long would. GDB should evaluate
449 expressions just as the compiler would --- and the compiler
450 sees a cast as a simple reinterpretation of the pointer's
451 bits. */
452 if (code2 == TYPE_CODE_PTR)
453 longest = extract_unsigned_integer (value_contents (arg2),
454 TYPE_LENGTH (type2));
455 else
456 longest = value_as_long (arg2);
457 return value_from_longest (type, convert_to_boolean ?
458 (LONGEST) (longest ? 1 : 0) : longest);
460 else if (code1 == TYPE_CODE_PTR && (code2 == TYPE_CODE_INT
461 || code2 == TYPE_CODE_ENUM
462 || code2 == TYPE_CODE_RANGE))
464 /* TYPE_LENGTH (type) is the length of a pointer, but we really
465 want the length of an address! -- we are really dealing with
466 addresses (i.e., gdb representations) not pointers (i.e.,
467 target representations) here.
469 This allows things like "print *(int *)0x01000234" to work
470 without printing a misleading message -- which would
471 otherwise occur when dealing with a target having two byte
472 pointers and four byte addresses. */
474 int addr_bit = gdbarch_addr_bit (current_gdbarch);
476 LONGEST longest = value_as_long (arg2);
477 if (addr_bit < sizeof (LONGEST) * HOST_CHAR_BIT)
479 if (longest >= ((LONGEST) 1 << addr_bit)
480 || longest <= -((LONGEST) 1 << addr_bit))
481 warning (_("value truncated"));
483 return value_from_longest (type, longest);
485 else if (code1 == TYPE_CODE_METHODPTR && code2 == TYPE_CODE_INT
486 && value_as_long (arg2) == 0)
488 struct value *result = allocate_value (type);
489 cplus_make_method_ptr (type, value_contents_writeable (result), 0, 0);
490 return result;
492 else if (code1 == TYPE_CODE_MEMBERPTR && code2 == TYPE_CODE_INT
493 && value_as_long (arg2) == 0)
495 /* The Itanium C++ ABI represents NULL pointers to members as
496 minus one, instead of biasing the normal case. */
497 return value_from_longest (type, -1);
499 else if (TYPE_LENGTH (type) == TYPE_LENGTH (type2))
501 if (code1 == TYPE_CODE_PTR && code2 == TYPE_CODE_PTR)
502 return value_cast_pointers (type, arg2);
504 arg2 = value_copy (arg2);
505 deprecated_set_value_type (arg2, type);
506 arg2 = value_change_enclosing_type (arg2, type);
507 set_value_pointed_to_offset (arg2, 0); /* pai: chk_val */
508 return arg2;
510 else if (VALUE_LVAL (arg2) == lval_memory)
511 return value_at_lazy (type, value_address (arg2));
512 else if (code1 == TYPE_CODE_VOID)
514 return value_zero (builtin_type_void, not_lval);
516 else
518 error (_("Invalid cast."));
519 return 0;
523 /* Create a value of type TYPE that is zero, and return it. */
525 struct value *
526 value_zero (struct type *type, enum lval_type lv)
528 struct value *val = allocate_value (type);
529 VALUE_LVAL (val) = lv;
531 return val;
534 /* Create a value of numeric type TYPE that is one, and return it. */
536 struct value *
537 value_one (struct type *type, enum lval_type lv)
539 struct type *type1 = check_typedef (type);
540 struct value *val = NULL; /* avoid -Wall warning */
542 if (TYPE_CODE (type1) == TYPE_CODE_DECFLOAT)
544 struct value *int_one = value_from_longest (builtin_type_int32, 1);
545 struct value *val;
546 gdb_byte v[16];
548 decimal_from_integral (int_one, v, TYPE_LENGTH (builtin_type_int32));
549 val = value_from_decfloat (type, v);
551 else if (TYPE_CODE (type1) == TYPE_CODE_FLT)
553 val = value_from_double (type, (DOUBLEST) 1);
555 else if (is_integral_type (type1))
557 val = value_from_longest (type, (LONGEST) 1);
559 else
561 error (_("Not a numeric type."));
564 VALUE_LVAL (val) = lv;
565 return val;
568 /* Return a value with type TYPE located at ADDR.
570 Call value_at only if the data needs to be fetched immediately;
571 if we can be 'lazy' and defer the fetch, perhaps indefinately, call
572 value_at_lazy instead. value_at_lazy simply records the address of
573 the data and sets the lazy-evaluation-required flag. The lazy flag
574 is tested in the value_contents macro, which is used if and when
575 the contents are actually required.
577 Note: value_at does *NOT* handle embedded offsets; perform such
578 adjustments before or after calling it. */
580 struct value *
581 value_at (struct type *type, CORE_ADDR addr)
583 struct value *val;
585 if (TYPE_CODE (check_typedef (type)) == TYPE_CODE_VOID)
586 error (_("Attempt to dereference a generic pointer."));
588 val = allocate_value (type);
590 read_memory (addr, value_contents_all_raw (val), TYPE_LENGTH (type));
592 VALUE_LVAL (val) = lval_memory;
593 set_value_address (val, addr);
595 return val;
598 /* Return a lazy value with type TYPE located at ADDR (cf. value_at). */
600 struct value *
601 value_at_lazy (struct type *type, CORE_ADDR addr)
603 struct value *val;
605 if (TYPE_CODE (check_typedef (type)) == TYPE_CODE_VOID)
606 error (_("Attempt to dereference a generic pointer."));
608 val = allocate_value_lazy (type);
610 VALUE_LVAL (val) = lval_memory;
611 set_value_address (val, addr);
613 return val;
616 /* Called only from the value_contents and value_contents_all()
617 macros, if the current data for a variable needs to be loaded into
618 value_contents(VAL). Fetches the data from the user's process, and
619 clears the lazy flag to indicate that the data in the buffer is
620 valid.
622 If the value is zero-length, we avoid calling read_memory, which
623 would abort. We mark the value as fetched anyway -- all 0 bytes of
626 This function returns a value because it is used in the
627 value_contents macro as part of an expression, where a void would
628 not work. The value is ignored. */
631 value_fetch_lazy (struct value *val)
633 gdb_assert (value_lazy (val));
634 allocate_value_contents (val);
635 if (VALUE_LVAL (val) == lval_memory)
637 CORE_ADDR addr = value_address (val);
638 int length = TYPE_LENGTH (check_typedef (value_enclosing_type (val)));
640 if (length)
641 read_memory (addr, value_contents_all_raw (val), length);
643 else if (VALUE_LVAL (val) == lval_register)
645 struct frame_info *frame;
646 int regnum;
647 struct type *type = check_typedef (value_type (val));
648 struct value *new_val = val, *mark = value_mark ();
650 /* Offsets are not supported here; lazy register values must
651 refer to the entire register. */
652 gdb_assert (value_offset (val) == 0);
654 while (VALUE_LVAL (new_val) == lval_register && value_lazy (new_val))
656 frame = frame_find_by_id (VALUE_FRAME_ID (new_val));
657 regnum = VALUE_REGNUM (new_val);
659 gdb_assert (frame != NULL);
661 /* Convertible register routines are used for multi-register
662 values and for interpretation in different types
663 (e.g. float or int from a double register). Lazy
664 register values should have the register's natural type,
665 so they do not apply. */
666 gdb_assert (!gdbarch_convert_register_p (get_frame_arch (frame),
667 regnum, type));
669 new_val = get_frame_register_value (frame, regnum);
672 /* If it's still lazy (for instance, a saved register on the
673 stack), fetch it. */
674 if (value_lazy (new_val))
675 value_fetch_lazy (new_val);
677 /* If the register was not saved, mark it unavailable. */
678 if (value_optimized_out (new_val))
679 set_value_optimized_out (val, 1);
680 else
681 memcpy (value_contents_raw (val), value_contents (new_val),
682 TYPE_LENGTH (type));
684 if (frame_debug)
686 struct gdbarch *gdbarch;
687 frame = frame_find_by_id (VALUE_FRAME_ID (val));
688 regnum = VALUE_REGNUM (val);
689 gdbarch = get_frame_arch (frame);
691 fprintf_unfiltered (gdb_stdlog, "\
692 { value_fetch_lazy (frame=%d,regnum=%d(%s),...) ",
693 frame_relative_level (frame), regnum,
694 user_reg_map_regnum_to_name (gdbarch, regnum));
696 fprintf_unfiltered (gdb_stdlog, "->");
697 if (value_optimized_out (new_val))
698 fprintf_unfiltered (gdb_stdlog, " optimized out");
699 else
701 int i;
702 const gdb_byte *buf = value_contents (new_val);
704 if (VALUE_LVAL (new_val) == lval_register)
705 fprintf_unfiltered (gdb_stdlog, " register=%d",
706 VALUE_REGNUM (new_val));
707 else if (VALUE_LVAL (new_val) == lval_memory)
708 fprintf_unfiltered (gdb_stdlog, " address=0x%s",
709 paddr_nz (value_address (new_val)));
710 else
711 fprintf_unfiltered (gdb_stdlog, " computed");
713 fprintf_unfiltered (gdb_stdlog, " bytes=");
714 fprintf_unfiltered (gdb_stdlog, "[");
715 for (i = 0; i < register_size (gdbarch, regnum); i++)
716 fprintf_unfiltered (gdb_stdlog, "%02x", buf[i]);
717 fprintf_unfiltered (gdb_stdlog, "]");
720 fprintf_unfiltered (gdb_stdlog, " }\n");
723 /* Dispose of the intermediate values. This prevents
724 watchpoints from trying to watch the saved frame pointer. */
725 value_free_to_mark (mark);
727 else if (VALUE_LVAL (val) == lval_computed)
728 value_computed_funcs (val)->read (val);
729 else
730 internal_error (__FILE__, __LINE__, "Unexpected lazy value type.");
732 set_value_lazy (val, 0);
733 return 0;
737 /* Store the contents of FROMVAL into the location of TOVAL.
738 Return a new value with the location of TOVAL and contents of FROMVAL. */
740 struct value *
741 value_assign (struct value *toval, struct value *fromval)
743 struct type *type;
744 struct value *val;
745 struct frame_id old_frame;
747 if (!deprecated_value_modifiable (toval))
748 error (_("Left operand of assignment is not a modifiable lvalue."));
750 toval = coerce_ref (toval);
752 type = value_type (toval);
753 if (VALUE_LVAL (toval) != lval_internalvar)
755 toval = value_coerce_to_target (toval);
756 fromval = value_cast (type, fromval);
758 else
760 /* Coerce arrays and functions to pointers, except for arrays
761 which only live in GDB's storage. */
762 if (!value_must_coerce_to_target (fromval))
763 fromval = coerce_array (fromval);
766 CHECK_TYPEDEF (type);
768 /* Since modifying a register can trash the frame chain, and
769 modifying memory can trash the frame cache, we save the old frame
770 and then restore the new frame afterwards. */
771 old_frame = get_frame_id (deprecated_safe_get_selected_frame ());
773 switch (VALUE_LVAL (toval))
775 case lval_internalvar:
776 set_internalvar (VALUE_INTERNALVAR (toval), fromval);
777 val = value_copy (fromval);
778 val = value_change_enclosing_type (val,
779 value_enclosing_type (fromval));
780 set_value_embedded_offset (val, value_embedded_offset (fromval));
781 set_value_pointed_to_offset (val,
782 value_pointed_to_offset (fromval));
783 return val;
785 case lval_internalvar_component:
786 set_internalvar_component (VALUE_INTERNALVAR (toval),
787 value_offset (toval),
788 value_bitpos (toval),
789 value_bitsize (toval),
790 fromval);
791 break;
793 case lval_memory:
795 const gdb_byte *dest_buffer;
796 CORE_ADDR changed_addr;
797 int changed_len;
798 gdb_byte buffer[sizeof (LONGEST)];
800 if (value_bitsize (toval))
802 /* We assume that the argument to read_memory is in units
803 of host chars. FIXME: Is that correct? */
804 changed_len = (value_bitpos (toval)
805 + value_bitsize (toval)
806 + HOST_CHAR_BIT - 1)
807 / HOST_CHAR_BIT;
809 if (changed_len > (int) sizeof (LONGEST))
810 error (_("Can't handle bitfields which don't fit in a %d bit word."),
811 (int) sizeof (LONGEST) * HOST_CHAR_BIT);
813 read_memory (value_address (toval), buffer, changed_len);
814 modify_field (buffer, value_as_long (fromval),
815 value_bitpos (toval), value_bitsize (toval));
816 changed_addr = value_address (toval);
817 dest_buffer = buffer;
819 else
821 changed_addr = value_address (toval);
822 changed_len = TYPE_LENGTH (type);
823 dest_buffer = value_contents (fromval);
826 write_memory (changed_addr, dest_buffer, changed_len);
827 if (deprecated_memory_changed_hook)
828 deprecated_memory_changed_hook (changed_addr, changed_len);
830 break;
832 case lval_register:
834 struct frame_info *frame;
835 int value_reg;
837 /* Figure out which frame this is in currently. */
838 frame = frame_find_by_id (VALUE_FRAME_ID (toval));
839 value_reg = VALUE_REGNUM (toval);
841 if (!frame)
842 error (_("Value being assigned to is no longer active."));
844 if (gdbarch_convert_register_p
845 (current_gdbarch, VALUE_REGNUM (toval), type))
847 /* If TOVAL is a special machine register requiring
848 conversion of program values to a special raw
849 format. */
850 gdbarch_value_to_register (current_gdbarch, frame,
851 VALUE_REGNUM (toval), type,
852 value_contents (fromval));
854 else
856 if (value_bitsize (toval))
858 int changed_len;
859 gdb_byte buffer[sizeof (LONGEST)];
861 changed_len = (value_bitpos (toval)
862 + value_bitsize (toval)
863 + HOST_CHAR_BIT - 1)
864 / HOST_CHAR_BIT;
866 if (changed_len > (int) sizeof (LONGEST))
867 error (_("Can't handle bitfields which don't fit in a %d bit word."),
868 (int) sizeof (LONGEST) * HOST_CHAR_BIT);
870 get_frame_register_bytes (frame, value_reg,
871 value_offset (toval),
872 changed_len, buffer);
874 modify_field (buffer, value_as_long (fromval),
875 value_bitpos (toval),
876 value_bitsize (toval));
878 put_frame_register_bytes (frame, value_reg,
879 value_offset (toval),
880 changed_len, buffer);
882 else
884 put_frame_register_bytes (frame, value_reg,
885 value_offset (toval),
886 TYPE_LENGTH (type),
887 value_contents (fromval));
891 if (deprecated_register_changed_hook)
892 deprecated_register_changed_hook (-1);
893 observer_notify_target_changed (&current_target);
894 break;
897 case lval_computed:
899 struct lval_funcs *funcs = value_computed_funcs (toval);
901 funcs->write (toval, fromval);
903 break;
905 default:
906 error (_("Left operand of assignment is not an lvalue."));
909 /* Assigning to the stack pointer, frame pointer, and other
910 (architecture and calling convention specific) registers may
911 cause the frame cache to be out of date. Assigning to memory
912 also can. We just do this on all assignments to registers or
913 memory, for simplicity's sake; I doubt the slowdown matters. */
914 switch (VALUE_LVAL (toval))
916 case lval_memory:
917 case lval_register:
919 reinit_frame_cache ();
921 /* Having destroyed the frame cache, restore the selected
922 frame. */
924 /* FIXME: cagney/2002-11-02: There has to be a better way of
925 doing this. Instead of constantly saving/restoring the
926 frame. Why not create a get_selected_frame() function that,
927 having saved the selected frame's ID can automatically
928 re-find the previously selected frame automatically. */
931 struct frame_info *fi = frame_find_by_id (old_frame);
932 if (fi != NULL)
933 select_frame (fi);
936 break;
937 default:
938 break;
941 /* If the field does not entirely fill a LONGEST, then zero the sign
942 bits. If the field is signed, and is negative, then sign
943 extend. */
944 if ((value_bitsize (toval) > 0)
945 && (value_bitsize (toval) < 8 * (int) sizeof (LONGEST)))
947 LONGEST fieldval = value_as_long (fromval);
948 LONGEST valmask = (((ULONGEST) 1) << value_bitsize (toval)) - 1;
950 fieldval &= valmask;
951 if (!TYPE_UNSIGNED (type)
952 && (fieldval & (valmask ^ (valmask >> 1))))
953 fieldval |= ~valmask;
955 fromval = value_from_longest (type, fieldval);
958 val = value_copy (toval);
959 memcpy (value_contents_raw (val), value_contents (fromval),
960 TYPE_LENGTH (type));
961 deprecated_set_value_type (val, type);
962 val = value_change_enclosing_type (val,
963 value_enclosing_type (fromval));
964 set_value_embedded_offset (val, value_embedded_offset (fromval));
965 set_value_pointed_to_offset (val, value_pointed_to_offset (fromval));
967 return val;
970 /* Extend a value VAL to COUNT repetitions of its type. */
972 struct value *
973 value_repeat (struct value *arg1, int count)
975 struct value *val;
977 if (VALUE_LVAL (arg1) != lval_memory)
978 error (_("Only values in memory can be extended with '@'."));
979 if (count < 1)
980 error (_("Invalid number %d of repetitions."), count);
982 val = allocate_repeat_value (value_enclosing_type (arg1), count);
984 read_memory (value_address (arg1),
985 value_contents_all_raw (val),
986 TYPE_LENGTH (value_enclosing_type (val)));
987 VALUE_LVAL (val) = lval_memory;
988 set_value_address (val, value_address (arg1));
990 return val;
993 struct value *
994 value_of_variable (struct symbol *var, struct block *b)
996 struct value *val;
997 struct frame_info *frame;
999 if (!symbol_read_needs_frame (var))
1000 frame = NULL;
1001 else if (!b)
1002 frame = get_selected_frame (_("No frame selected."));
1003 else
1005 frame = block_innermost_frame (b);
1006 if (!frame)
1008 if (BLOCK_FUNCTION (b)
1009 && SYMBOL_PRINT_NAME (BLOCK_FUNCTION (b)))
1010 error (_("No frame is currently executing in block %s."),
1011 SYMBOL_PRINT_NAME (BLOCK_FUNCTION (b)));
1012 else
1013 error (_("No frame is currently executing in specified block"));
1017 val = read_var_value (var, frame);
1018 if (!val)
1019 error (_("Address of symbol \"%s\" is unknown."), SYMBOL_PRINT_NAME (var));
1021 return val;
1024 struct value *
1025 address_of_variable (struct symbol *var, struct block *b)
1027 struct type *type = SYMBOL_TYPE (var);
1028 struct value *val;
1030 /* Evaluate it first; if the result is a memory address, we're fine.
1031 Lazy evaluation pays off here. */
1033 val = value_of_variable (var, b);
1035 if ((VALUE_LVAL (val) == lval_memory && value_lazy (val))
1036 || TYPE_CODE (type) == TYPE_CODE_FUNC)
1038 CORE_ADDR addr = value_address (val);
1039 return value_from_pointer (lookup_pointer_type (type), addr);
1042 /* Not a memory address; check what the problem was. */
1043 switch (VALUE_LVAL (val))
1045 case lval_register:
1047 struct frame_info *frame;
1048 const char *regname;
1050 frame = frame_find_by_id (VALUE_FRAME_ID (val));
1051 gdb_assert (frame);
1053 regname = gdbarch_register_name (get_frame_arch (frame),
1054 VALUE_REGNUM (val));
1055 gdb_assert (regname && *regname);
1057 error (_("Address requested for identifier "
1058 "\"%s\" which is in register $%s"),
1059 SYMBOL_PRINT_NAME (var), regname);
1060 break;
1063 default:
1064 error (_("Can't take address of \"%s\" which isn't an lvalue."),
1065 SYMBOL_PRINT_NAME (var));
1066 break;
1069 return val;
1072 /* Return one if VAL does not live in target memory, but should in order
1073 to operate on it. Otherwise return zero. */
1076 value_must_coerce_to_target (struct value *val)
1078 struct type *valtype;
1080 /* The only lval kinds which do not live in target memory. */
1081 if (VALUE_LVAL (val) != not_lval
1082 && VALUE_LVAL (val) != lval_internalvar)
1083 return 0;
1085 valtype = check_typedef (value_type (val));
1087 switch (TYPE_CODE (valtype))
1089 case TYPE_CODE_ARRAY:
1090 case TYPE_CODE_STRING:
1091 return 1;
1092 default:
1093 return 0;
1097 /* Make sure that VAL lives in target memory if it's supposed to. For instance,
1098 strings are constructed as character arrays in GDB's storage, and this
1099 function copies them to the target. */
1101 struct value *
1102 value_coerce_to_target (struct value *val)
1104 LONGEST length;
1105 CORE_ADDR addr;
1107 if (!value_must_coerce_to_target (val))
1108 return val;
1110 length = TYPE_LENGTH (check_typedef (value_type (val)));
1111 addr = allocate_space_in_inferior (length);
1112 write_memory (addr, value_contents (val), length);
1113 return value_at_lazy (value_type (val), addr);
1116 /* Given a value which is an array, return a value which is a pointer
1117 to its first element, regardless of whether or not the array has a
1118 nonzero lower bound.
1120 FIXME: A previous comment here indicated that this routine should
1121 be substracting the array's lower bound. It's not clear to me that
1122 this is correct. Given an array subscripting operation, it would
1123 certainly work to do the adjustment here, essentially computing:
1125 (&array[0] - (lowerbound * sizeof array[0])) + (index * sizeof array[0])
1127 However I believe a more appropriate and logical place to account
1128 for the lower bound is to do so in value_subscript, essentially
1129 computing:
1131 (&array[0] + ((index - lowerbound) * sizeof array[0]))
1133 As further evidence consider what would happen with operations
1134 other than array subscripting, where the caller would get back a
1135 value that had an address somewhere before the actual first element
1136 of the array, and the information about the lower bound would be
1137 lost because of the coercion to pointer type.
1140 struct value *
1141 value_coerce_array (struct value *arg1)
1143 struct type *type = check_typedef (value_type (arg1));
1145 /* If the user tries to do something requiring a pointer with an
1146 array that has not yet been pushed to the target, then this would
1147 be a good time to do so. */
1148 arg1 = value_coerce_to_target (arg1);
1150 if (VALUE_LVAL (arg1) != lval_memory)
1151 error (_("Attempt to take address of value not located in memory."));
1153 return value_from_pointer (lookup_pointer_type (TYPE_TARGET_TYPE (type)),
1154 value_address (arg1));
1157 /* Given a value which is a function, return a value which is a pointer
1158 to it. */
1160 struct value *
1161 value_coerce_function (struct value *arg1)
1163 struct value *retval;
1165 if (VALUE_LVAL (arg1) != lval_memory)
1166 error (_("Attempt to take address of value not located in memory."));
1168 retval = value_from_pointer (lookup_pointer_type (value_type (arg1)),
1169 value_address (arg1));
1170 return retval;
1173 /* Return a pointer value for the object for which ARG1 is the
1174 contents. */
1176 struct value *
1177 value_addr (struct value *arg1)
1179 struct value *arg2;
1181 struct type *type = check_typedef (value_type (arg1));
1182 if (TYPE_CODE (type) == TYPE_CODE_REF)
1184 /* Copy the value, but change the type from (T&) to (T*). We
1185 keep the same location information, which is efficient, and
1186 allows &(&X) to get the location containing the reference. */
1187 arg2 = value_copy (arg1);
1188 deprecated_set_value_type (arg2,
1189 lookup_pointer_type (TYPE_TARGET_TYPE (type)));
1190 return arg2;
1192 if (TYPE_CODE (type) == TYPE_CODE_FUNC)
1193 return value_coerce_function (arg1);
1195 /* If this is an array that has not yet been pushed to the target,
1196 then this would be a good time to force it to memory. */
1197 arg1 = value_coerce_to_target (arg1);
1199 if (VALUE_LVAL (arg1) != lval_memory)
1200 error (_("Attempt to take address of value not located in memory."));
1202 /* Get target memory address */
1203 arg2 = value_from_pointer (lookup_pointer_type (value_type (arg1)),
1204 (value_address (arg1)
1205 + value_embedded_offset (arg1)));
1207 /* This may be a pointer to a base subobject; so remember the
1208 full derived object's type ... */
1209 arg2 = value_change_enclosing_type (arg2, lookup_pointer_type (value_enclosing_type (arg1)));
1210 /* ... and also the relative position of the subobject in the full
1211 object. */
1212 set_value_pointed_to_offset (arg2, value_embedded_offset (arg1));
1213 return arg2;
1216 /* Return a reference value for the object for which ARG1 is the
1217 contents. */
1219 struct value *
1220 value_ref (struct value *arg1)
1222 struct value *arg2;
1224 struct type *type = check_typedef (value_type (arg1));
1225 if (TYPE_CODE (type) == TYPE_CODE_REF)
1226 return arg1;
1228 arg2 = value_addr (arg1);
1229 deprecated_set_value_type (arg2, lookup_reference_type (type));
1230 return arg2;
1233 /* Given a value of a pointer type, apply the C unary * operator to
1234 it. */
1236 struct value *
1237 value_ind (struct value *arg1)
1239 struct type *base_type;
1240 struct value *arg2;
1242 arg1 = coerce_array (arg1);
1244 base_type = check_typedef (value_type (arg1));
1246 if (TYPE_CODE (base_type) == TYPE_CODE_PTR)
1248 struct type *enc_type;
1249 /* We may be pointing to something embedded in a larger object.
1250 Get the real type of the enclosing object. */
1251 enc_type = check_typedef (value_enclosing_type (arg1));
1252 enc_type = TYPE_TARGET_TYPE (enc_type);
1254 if (TYPE_CODE (check_typedef (enc_type)) == TYPE_CODE_FUNC
1255 || TYPE_CODE (check_typedef (enc_type)) == TYPE_CODE_METHOD)
1256 /* For functions, go through find_function_addr, which knows
1257 how to handle function descriptors. */
1258 arg2 = value_at_lazy (enc_type,
1259 find_function_addr (arg1, NULL));
1260 else
1261 /* Retrieve the enclosing object pointed to */
1262 arg2 = value_at_lazy (enc_type,
1263 (value_as_address (arg1)
1264 - value_pointed_to_offset (arg1)));
1266 /* Re-adjust type. */
1267 deprecated_set_value_type (arg2, TYPE_TARGET_TYPE (base_type));
1268 /* Add embedding info. */
1269 arg2 = value_change_enclosing_type (arg2, enc_type);
1270 set_value_embedded_offset (arg2, value_pointed_to_offset (arg1));
1272 /* We may be pointing to an object of some derived type. */
1273 arg2 = value_full_object (arg2, NULL, 0, 0, 0);
1274 return arg2;
1277 error (_("Attempt to take contents of a non-pointer value."));
1278 return 0; /* For lint -- never reached. */
1281 /* Create a value for an array by allocating space in GDB, copying
1282 copying the data into that space, and then setting up an array
1283 value.
1285 The array bounds are set from LOWBOUND and HIGHBOUND, and the array
1286 is populated from the values passed in ELEMVEC.
1288 The element type of the array is inherited from the type of the
1289 first element, and all elements must have the same size (though we
1290 don't currently enforce any restriction on their types). */
1292 struct value *
1293 value_array (int lowbound, int highbound, struct value **elemvec)
1295 int nelem;
1296 int idx;
1297 unsigned int typelength;
1298 struct value *val;
1299 struct type *rangetype;
1300 struct type *arraytype;
1301 CORE_ADDR addr;
1303 /* Validate that the bounds are reasonable and that each of the
1304 elements have the same size. */
1306 nelem = highbound - lowbound + 1;
1307 if (nelem <= 0)
1309 error (_("bad array bounds (%d, %d)"), lowbound, highbound);
1311 typelength = TYPE_LENGTH (value_enclosing_type (elemvec[0]));
1312 for (idx = 1; idx < nelem; idx++)
1314 if (TYPE_LENGTH (value_enclosing_type (elemvec[idx])) != typelength)
1316 error (_("array elements must all be the same size"));
1320 rangetype = create_range_type ((struct type *) NULL,
1321 builtin_type_int32,
1322 lowbound, highbound);
1323 arraytype = create_array_type ((struct type *) NULL,
1324 value_enclosing_type (elemvec[0]),
1325 rangetype);
1327 if (!current_language->c_style_arrays)
1329 val = allocate_value (arraytype);
1330 for (idx = 0; idx < nelem; idx++)
1332 memcpy (value_contents_all_raw (val) + (idx * typelength),
1333 value_contents_all (elemvec[idx]),
1334 typelength);
1336 return val;
1339 /* Allocate space to store the array, and then initialize it by
1340 copying in each element. */
1342 val = allocate_value (arraytype);
1343 for (idx = 0; idx < nelem; idx++)
1344 memcpy (value_contents_writeable (val) + (idx * typelength),
1345 value_contents_all (elemvec[idx]),
1346 typelength);
1347 return val;
1350 struct value *
1351 value_typed_string (char *ptr, int len, struct type *char_type)
1353 struct value *val;
1354 int lowbound = current_language->string_lower_bound;
1355 int highbound = len / TYPE_LENGTH (char_type);
1356 struct type *rangetype = create_range_type ((struct type *) NULL,
1357 builtin_type_int32,
1358 lowbound,
1359 highbound + lowbound - 1);
1360 struct type *stringtype
1361 = create_array_type ((struct type *) NULL, char_type, rangetype);
1363 val = allocate_value (stringtype);
1364 memcpy (value_contents_raw (val), ptr, len);
1365 return val;
1368 /* Create a value for a string constant by allocating space in the
1369 inferior, copying the data into that space, and returning the
1370 address with type TYPE_CODE_STRING. PTR points to the string
1371 constant data; LEN is number of characters.
1373 Note that string types are like array of char types with a lower
1374 bound of zero and an upper bound of LEN - 1. Also note that the
1375 string may contain embedded null bytes. */
1377 struct value *
1378 value_string (char *ptr, int len)
1380 struct value *val;
1381 int lowbound = current_language->string_lower_bound;
1382 struct type *rangetype = create_range_type ((struct type *) NULL,
1383 builtin_type_int32,
1384 lowbound,
1385 len + lowbound - 1);
1386 struct type *stringtype
1387 = create_string_type ((struct type *) NULL, rangetype);
1388 CORE_ADDR addr;
1390 if (current_language->c_style_arrays == 0)
1392 val = allocate_value (stringtype);
1393 memcpy (value_contents_raw (val), ptr, len);
1394 return val;
1398 /* Allocate space to store the string in the inferior, and then copy
1399 LEN bytes from PTR in gdb to that address in the inferior. */
1401 addr = allocate_space_in_inferior (len);
1402 write_memory (addr, (gdb_byte *) ptr, len);
1404 val = value_at_lazy (stringtype, addr);
1405 return (val);
1408 struct value *
1409 value_bitstring (char *ptr, int len)
1411 struct value *val;
1412 struct type *domain_type = create_range_type (NULL,
1413 builtin_type_int32,
1414 0, len - 1);
1415 struct type *type = create_set_type ((struct type *) NULL,
1416 domain_type);
1417 TYPE_CODE (type) = TYPE_CODE_BITSTRING;
1418 val = allocate_value (type);
1419 memcpy (value_contents_raw (val), ptr, TYPE_LENGTH (type));
1420 return val;
1423 /* See if we can pass arguments in T2 to a function which takes
1424 arguments of types T1. T1 is a list of NARGS arguments, and T2 is
1425 a NULL-terminated vector. If some arguments need coercion of some
1426 sort, then the coerced values are written into T2. Return value is
1427 0 if the arguments could be matched, or the position at which they
1428 differ if not.
1430 STATICP is nonzero if the T1 argument list came from a static
1431 member function. T2 will still include the ``this'' pointer, but
1432 it will be skipped.
1434 For non-static member functions, we ignore the first argument,
1435 which is the type of the instance variable. This is because we
1436 want to handle calls with objects from derived classes. This is
1437 not entirely correct: we should actually check to make sure that a
1438 requested operation is type secure, shouldn't we? FIXME. */
1440 static int
1441 typecmp (int staticp, int varargs, int nargs,
1442 struct field t1[], struct value *t2[])
1444 int i;
1446 if (t2 == 0)
1447 internal_error (__FILE__, __LINE__,
1448 _("typecmp: no argument list"));
1450 /* Skip ``this'' argument if applicable. T2 will always include
1451 THIS. */
1452 if (staticp)
1453 t2 ++;
1455 for (i = 0;
1456 (i < nargs) && TYPE_CODE (t1[i].type) != TYPE_CODE_VOID;
1457 i++)
1459 struct type *tt1, *tt2;
1461 if (!t2[i])
1462 return i + 1;
1464 tt1 = check_typedef (t1[i].type);
1465 tt2 = check_typedef (value_type (t2[i]));
1467 if (TYPE_CODE (tt1) == TYPE_CODE_REF
1468 /* We should be doing hairy argument matching, as below. */
1469 && (TYPE_CODE (check_typedef (TYPE_TARGET_TYPE (tt1))) == TYPE_CODE (tt2)))
1471 if (TYPE_CODE (tt2) == TYPE_CODE_ARRAY)
1472 t2[i] = value_coerce_array (t2[i]);
1473 else
1474 t2[i] = value_ref (t2[i]);
1475 continue;
1478 /* djb - 20000715 - Until the new type structure is in the
1479 place, and we can attempt things like implicit conversions,
1480 we need to do this so you can take something like a map<const
1481 char *>, and properly access map["hello"], because the
1482 argument to [] will be a reference to a pointer to a char,
1483 and the argument will be a pointer to a char. */
1484 while (TYPE_CODE(tt1) == TYPE_CODE_REF
1485 || TYPE_CODE (tt1) == TYPE_CODE_PTR)
1487 tt1 = check_typedef( TYPE_TARGET_TYPE(tt1) );
1489 while (TYPE_CODE(tt2) == TYPE_CODE_ARRAY
1490 || TYPE_CODE(tt2) == TYPE_CODE_PTR
1491 || TYPE_CODE(tt2) == TYPE_CODE_REF)
1493 tt2 = check_typedef (TYPE_TARGET_TYPE(tt2));
1495 if (TYPE_CODE (tt1) == TYPE_CODE (tt2))
1496 continue;
1497 /* Array to pointer is a `trivial conversion' according to the
1498 ARM. */
1500 /* We should be doing much hairier argument matching (see
1501 section 13.2 of the ARM), but as a quick kludge, just check
1502 for the same type code. */
1503 if (TYPE_CODE (t1[i].type) != TYPE_CODE (value_type (t2[i])))
1504 return i + 1;
1506 if (varargs || t2[i] == NULL)
1507 return 0;
1508 return i + 1;
1511 /* Helper function used by value_struct_elt to recurse through
1512 baseclasses. Look for a field NAME in ARG1. Adjust the address of
1513 ARG1 by OFFSET bytes, and search in it assuming it has (class) type
1514 TYPE. If found, return value, else return NULL.
1516 If LOOKING_FOR_BASECLASS, then instead of looking for struct
1517 fields, look for a baseclass named NAME. */
1519 static struct value *
1520 search_struct_field (char *name, struct value *arg1, int offset,
1521 struct type *type, int looking_for_baseclass)
1523 int i;
1524 int nbases = TYPE_N_BASECLASSES (type);
1526 CHECK_TYPEDEF (type);
1528 if (!looking_for_baseclass)
1529 for (i = TYPE_NFIELDS (type) - 1; i >= nbases; i--)
1531 char *t_field_name = TYPE_FIELD_NAME (type, i);
1533 if (t_field_name && (strcmp_iw (t_field_name, name) == 0))
1535 struct value *v;
1536 if (field_is_static (&TYPE_FIELD (type, i)))
1538 v = value_static_field (type, i);
1539 if (v == 0)
1540 error (_("field %s is nonexistent or has been optimised out"),
1541 name);
1543 else
1545 v = value_primitive_field (arg1, offset, i, type);
1546 if (v == 0)
1547 error (_("there is no field named %s"), name);
1549 return v;
1552 if (t_field_name
1553 && (t_field_name[0] == '\0'
1554 || (TYPE_CODE (type) == TYPE_CODE_UNION
1555 && (strcmp_iw (t_field_name, "else") == 0))))
1557 struct type *field_type = TYPE_FIELD_TYPE (type, i);
1558 if (TYPE_CODE (field_type) == TYPE_CODE_UNION
1559 || TYPE_CODE (field_type) == TYPE_CODE_STRUCT)
1561 /* Look for a match through the fields of an anonymous
1562 union, or anonymous struct. C++ provides anonymous
1563 unions.
1565 In the GNU Chill (now deleted from GDB)
1566 implementation of variant record types, each
1567 <alternative field> has an (anonymous) union type,
1568 each member of the union represents a <variant
1569 alternative>. Each <variant alternative> is
1570 represented as a struct, with a member for each
1571 <variant field>. */
1573 struct value *v;
1574 int new_offset = offset;
1576 /* This is pretty gross. In G++, the offset in an
1577 anonymous union is relative to the beginning of the
1578 enclosing struct. In the GNU Chill (now deleted
1579 from GDB) implementation of variant records, the
1580 bitpos is zero in an anonymous union field, so we
1581 have to add the offset of the union here. */
1582 if (TYPE_CODE (field_type) == TYPE_CODE_STRUCT
1583 || (TYPE_NFIELDS (field_type) > 0
1584 && TYPE_FIELD_BITPOS (field_type, 0) == 0))
1585 new_offset += TYPE_FIELD_BITPOS (type, i) / 8;
1587 v = search_struct_field (name, arg1, new_offset,
1588 field_type,
1589 looking_for_baseclass);
1590 if (v)
1591 return v;
1596 for (i = 0; i < nbases; i++)
1598 struct value *v;
1599 struct type *basetype = check_typedef (TYPE_BASECLASS (type, i));
1600 /* If we are looking for baseclasses, this is what we get when
1601 we hit them. But it could happen that the base part's member
1602 name is not yet filled in. */
1603 int found_baseclass = (looking_for_baseclass
1604 && TYPE_BASECLASS_NAME (type, i) != NULL
1605 && (strcmp_iw (name,
1606 TYPE_BASECLASS_NAME (type,
1607 i)) == 0));
1609 if (BASETYPE_VIA_VIRTUAL (type, i))
1611 int boffset;
1612 struct value *v2;
1614 boffset = baseclass_offset (type, i,
1615 value_contents (arg1) + offset,
1616 value_address (arg1) + offset);
1617 if (boffset == -1)
1618 error (_("virtual baseclass botch"));
1620 /* The virtual base class pointer might have been clobbered
1621 by the user program. Make sure that it still points to a
1622 valid memory location. */
1624 boffset += offset;
1625 if (boffset < 0 || boffset >= TYPE_LENGTH (type))
1627 CORE_ADDR base_addr;
1629 v2 = allocate_value (basetype);
1630 base_addr = value_address (arg1) + boffset;
1631 if (target_read_memory (base_addr,
1632 value_contents_raw (v2),
1633 TYPE_LENGTH (basetype)) != 0)
1634 error (_("virtual baseclass botch"));
1635 VALUE_LVAL (v2) = lval_memory;
1636 set_value_address (v2, base_addr);
1638 else
1640 if (VALUE_LVAL (arg1) == lval_memory && value_lazy (arg1))
1641 v2 = allocate_value_lazy (basetype);
1642 else
1644 v2 = allocate_value (basetype);
1645 memcpy (value_contents_raw (v2),
1646 value_contents_raw (arg1) + boffset,
1647 TYPE_LENGTH (basetype));
1649 set_value_component_location (v2, arg1);
1650 VALUE_FRAME_ID (v2) = VALUE_FRAME_ID (arg1);
1651 set_value_offset (v2, value_offset (arg1) + boffset);
1654 if (found_baseclass)
1655 return v2;
1656 v = search_struct_field (name, v2, 0,
1657 TYPE_BASECLASS (type, i),
1658 looking_for_baseclass);
1660 else if (found_baseclass)
1661 v = value_primitive_field (arg1, offset, i, type);
1662 else
1663 v = search_struct_field (name, arg1,
1664 offset + TYPE_BASECLASS_BITPOS (type,
1665 i) / 8,
1666 basetype, looking_for_baseclass);
1667 if (v)
1668 return v;
1670 return NULL;
1673 /* Helper function used by value_struct_elt to recurse through
1674 baseclasses. Look for a field NAME in ARG1. Adjust the address of
1675 ARG1 by OFFSET bytes, and search in it assuming it has (class) type
1676 TYPE.
1678 If found, return value, else if name matched and args not return
1679 (value) -1, else return NULL. */
1681 static struct value *
1682 search_struct_method (char *name, struct value **arg1p,
1683 struct value **args, int offset,
1684 int *static_memfuncp, struct type *type)
1686 int i;
1687 struct value *v;
1688 int name_matched = 0;
1689 char dem_opname[64];
1691 CHECK_TYPEDEF (type);
1692 for (i = TYPE_NFN_FIELDS (type) - 1; i >= 0; i--)
1694 char *t_field_name = TYPE_FN_FIELDLIST_NAME (type, i);
1695 /* FIXME! May need to check for ARM demangling here */
1696 if (strncmp (t_field_name, "__", 2) == 0 ||
1697 strncmp (t_field_name, "op", 2) == 0 ||
1698 strncmp (t_field_name, "type", 4) == 0)
1700 if (cplus_demangle_opname (t_field_name, dem_opname, DMGL_ANSI))
1701 t_field_name = dem_opname;
1702 else if (cplus_demangle_opname (t_field_name, dem_opname, 0))
1703 t_field_name = dem_opname;
1705 if (t_field_name && (strcmp_iw (t_field_name, name) == 0))
1707 int j = TYPE_FN_FIELDLIST_LENGTH (type, i) - 1;
1708 struct fn_field *f = TYPE_FN_FIELDLIST1 (type, i);
1709 name_matched = 1;
1711 check_stub_method_group (type, i);
1712 if (j > 0 && args == 0)
1713 error (_("cannot resolve overloaded method `%s': no arguments supplied"), name);
1714 else if (j == 0 && args == 0)
1716 v = value_fn_field (arg1p, f, j, type, offset);
1717 if (v != NULL)
1718 return v;
1720 else
1721 while (j >= 0)
1723 if (!typecmp (TYPE_FN_FIELD_STATIC_P (f, j),
1724 TYPE_VARARGS (TYPE_FN_FIELD_TYPE (f, j)),
1725 TYPE_NFIELDS (TYPE_FN_FIELD_TYPE (f, j)),
1726 TYPE_FN_FIELD_ARGS (f, j), args))
1728 if (TYPE_FN_FIELD_VIRTUAL_P (f, j))
1729 return value_virtual_fn_field (arg1p, f, j,
1730 type, offset);
1731 if (TYPE_FN_FIELD_STATIC_P (f, j)
1732 && static_memfuncp)
1733 *static_memfuncp = 1;
1734 v = value_fn_field (arg1p, f, j, type, offset);
1735 if (v != NULL)
1736 return v;
1738 j--;
1743 for (i = TYPE_N_BASECLASSES (type) - 1; i >= 0; i--)
1745 int base_offset;
1747 if (BASETYPE_VIA_VIRTUAL (type, i))
1749 struct type *baseclass = check_typedef (TYPE_BASECLASS (type, i));
1750 const gdb_byte *base_valaddr;
1752 /* The virtual base class pointer might have been
1753 clobbered by the user program. Make sure that it
1754 still points to a valid memory location. */
1756 if (offset < 0 || offset >= TYPE_LENGTH (type))
1758 gdb_byte *tmp = alloca (TYPE_LENGTH (baseclass));
1759 if (target_read_memory (value_address (*arg1p) + offset,
1760 tmp, TYPE_LENGTH (baseclass)) != 0)
1761 error (_("virtual baseclass botch"));
1762 base_valaddr = tmp;
1764 else
1765 base_valaddr = value_contents (*arg1p) + offset;
1767 base_offset = baseclass_offset (type, i, base_valaddr,
1768 value_address (*arg1p) + offset);
1769 if (base_offset == -1)
1770 error (_("virtual baseclass botch"));
1772 else
1774 base_offset = TYPE_BASECLASS_BITPOS (type, i) / 8;
1776 v = search_struct_method (name, arg1p, args, base_offset + offset,
1777 static_memfuncp, TYPE_BASECLASS (type, i));
1778 if (v == (struct value *) - 1)
1780 name_matched = 1;
1782 else if (v)
1784 /* FIXME-bothner: Why is this commented out? Why is it here? */
1785 /* *arg1p = arg1_tmp; */
1786 return v;
1789 if (name_matched)
1790 return (struct value *) - 1;
1791 else
1792 return NULL;
1795 /* Given *ARGP, a value of type (pointer to a)* structure/union,
1796 extract the component named NAME from the ultimate target
1797 structure/union and return it as a value with its appropriate type.
1798 ERR is used in the error message if *ARGP's type is wrong.
1800 C++: ARGS is a list of argument types to aid in the selection of
1801 an appropriate method. Also, handle derived types.
1803 STATIC_MEMFUNCP, if non-NULL, points to a caller-supplied location
1804 where the truthvalue of whether the function that was resolved was
1805 a static member function or not is stored.
1807 ERR is an error message to be printed in case the field is not
1808 found. */
1810 struct value *
1811 value_struct_elt (struct value **argp, struct value **args,
1812 char *name, int *static_memfuncp, char *err)
1814 struct type *t;
1815 struct value *v;
1817 *argp = coerce_array (*argp);
1819 t = check_typedef (value_type (*argp));
1821 /* Follow pointers until we get to a non-pointer. */
1823 while (TYPE_CODE (t) == TYPE_CODE_PTR || TYPE_CODE (t) == TYPE_CODE_REF)
1825 *argp = value_ind (*argp);
1826 /* Don't coerce fn pointer to fn and then back again! */
1827 if (TYPE_CODE (value_type (*argp)) != TYPE_CODE_FUNC)
1828 *argp = coerce_array (*argp);
1829 t = check_typedef (value_type (*argp));
1832 if (TYPE_CODE (t) != TYPE_CODE_STRUCT
1833 && TYPE_CODE (t) != TYPE_CODE_UNION)
1834 error (_("Attempt to extract a component of a value that is not a %s."), err);
1836 /* Assume it's not, unless we see that it is. */
1837 if (static_memfuncp)
1838 *static_memfuncp = 0;
1840 if (!args)
1842 /* if there are no arguments ...do this... */
1844 /* Try as a field first, because if we succeed, there is less
1845 work to be done. */
1846 v = search_struct_field (name, *argp, 0, t, 0);
1847 if (v)
1848 return v;
1850 /* C++: If it was not found as a data field, then try to
1851 return it as a pointer to a method. */
1853 if (destructor_name_p (name, t))
1854 error (_("Cannot get value of destructor"));
1856 v = search_struct_method (name, argp, args, 0,
1857 static_memfuncp, t);
1859 if (v == (struct value *) - 1)
1860 error (_("Cannot take address of method %s."), name);
1861 else if (v == 0)
1863 if (TYPE_NFN_FIELDS (t))
1864 error (_("There is no member or method named %s."), name);
1865 else
1866 error (_("There is no member named %s."), name);
1868 return v;
1871 if (destructor_name_p (name, t))
1873 if (!args[1])
1875 /* Destructors are a special case. */
1876 int m_index, f_index;
1878 v = NULL;
1879 if (get_destructor_fn_field (t, &m_index, &f_index))
1881 v = value_fn_field (NULL,
1882 TYPE_FN_FIELDLIST1 (t, m_index),
1883 f_index, NULL, 0);
1885 if (v == NULL)
1886 error (_("could not find destructor function named %s."),
1887 name);
1888 else
1889 return v;
1891 else
1893 error (_("destructor should not have any argument"));
1896 else
1897 v = search_struct_method (name, argp, args, 0,
1898 static_memfuncp, t);
1900 if (v == (struct value *) - 1)
1902 error (_("One of the arguments you tried to pass to %s could not be converted to what the function wants."), name);
1904 else if (v == 0)
1906 /* See if user tried to invoke data as function. If so, hand it
1907 back. If it's not callable (i.e., a pointer to function),
1908 gdb should give an error. */
1909 v = search_struct_field (name, *argp, 0, t, 0);
1910 /* If we found an ordinary field, then it is not a method call.
1911 So, treat it as if it were a static member function. */
1912 if (v && static_memfuncp)
1913 *static_memfuncp = 1;
1916 if (!v)
1917 error (_("Structure has no component named %s."), name);
1918 return v;
1921 /* Search through the methods of an object (and its bases) to find a
1922 specified method. Return the pointer to the fn_field list of
1923 overloaded instances.
1925 Helper function for value_find_oload_list.
1926 ARGP is a pointer to a pointer to a value (the object).
1927 METHOD is a string containing the method name.
1928 OFFSET is the offset within the value.
1929 TYPE is the assumed type of the object.
1930 NUM_FNS is the number of overloaded instances.
1931 BASETYPE is set to the actual type of the subobject where the
1932 method is found.
1933 BOFFSET is the offset of the base subobject where the method is found.
1936 static struct fn_field *
1937 find_method_list (struct value **argp, char *method,
1938 int offset, struct type *type, int *num_fns,
1939 struct type **basetype, int *boffset)
1941 int i;
1942 struct fn_field *f;
1943 CHECK_TYPEDEF (type);
1945 *num_fns = 0;
1947 /* First check in object itself. */
1948 for (i = TYPE_NFN_FIELDS (type) - 1; i >= 0; i--)
1950 /* pai: FIXME What about operators and type conversions? */
1951 char *fn_field_name = TYPE_FN_FIELDLIST_NAME (type, i);
1952 if (fn_field_name && (strcmp_iw (fn_field_name, method) == 0))
1954 int len = TYPE_FN_FIELDLIST_LENGTH (type, i);
1955 struct fn_field *f = TYPE_FN_FIELDLIST1 (type, i);
1957 *num_fns = len;
1958 *basetype = type;
1959 *boffset = offset;
1961 /* Resolve any stub methods. */
1962 check_stub_method_group (type, i);
1964 return f;
1968 /* Not found in object, check in base subobjects. */
1969 for (i = TYPE_N_BASECLASSES (type) - 1; i >= 0; i--)
1971 int base_offset;
1972 if (BASETYPE_VIA_VIRTUAL (type, i))
1974 base_offset = value_offset (*argp) + offset;
1975 base_offset = baseclass_offset (type, i,
1976 value_contents (*argp) + base_offset,
1977 value_address (*argp) + base_offset);
1978 if (base_offset == -1)
1979 error (_("virtual baseclass botch"));
1981 else /* Non-virtual base, simply use bit position from debug
1982 info. */
1984 base_offset = TYPE_BASECLASS_BITPOS (type, i) / 8;
1986 f = find_method_list (argp, method, base_offset + offset,
1987 TYPE_BASECLASS (type, i), num_fns,
1988 basetype, boffset);
1989 if (f)
1990 return f;
1992 return NULL;
1995 /* Return the list of overloaded methods of a specified name.
1997 ARGP is a pointer to a pointer to a value (the object).
1998 METHOD is the method name.
1999 OFFSET is the offset within the value contents.
2000 NUM_FNS is the number of overloaded instances.
2001 BASETYPE is set to the type of the base subobject that defines the
2002 method.
2003 BOFFSET is the offset of the base subobject which defines the method.
2006 struct fn_field *
2007 value_find_oload_method_list (struct value **argp, char *method,
2008 int offset, int *num_fns,
2009 struct type **basetype, int *boffset)
2011 struct type *t;
2013 t = check_typedef (value_type (*argp));
2015 /* Code snarfed from value_struct_elt. */
2016 while (TYPE_CODE (t) == TYPE_CODE_PTR || TYPE_CODE (t) == TYPE_CODE_REF)
2018 *argp = value_ind (*argp);
2019 /* Don't coerce fn pointer to fn and then back again! */
2020 if (TYPE_CODE (value_type (*argp)) != TYPE_CODE_FUNC)
2021 *argp = coerce_array (*argp);
2022 t = check_typedef (value_type (*argp));
2025 if (TYPE_CODE (t) != TYPE_CODE_STRUCT
2026 && TYPE_CODE (t) != TYPE_CODE_UNION)
2027 error (_("Attempt to extract a component of a value that is not a struct or union"));
2029 return find_method_list (argp, method, 0, t, num_fns,
2030 basetype, boffset);
2033 /* Given an array of argument types (ARGTYPES) (which includes an
2034 entry for "this" in the case of C++ methods), the number of
2035 arguments NARGS, the NAME of a function whether it's a method or
2036 not (METHOD), and the degree of laxness (LAX) in conforming to
2037 overload resolution rules in ANSI C++, find the best function that
2038 matches on the argument types according to the overload resolution
2039 rules.
2041 In the case of class methods, the parameter OBJ is an object value
2042 in which to search for overloaded methods.
2044 In the case of non-method functions, the parameter FSYM is a symbol
2045 corresponding to one of the overloaded functions.
2047 Return value is an integer: 0 -> good match, 10 -> debugger applied
2048 non-standard coercions, 100 -> incompatible.
2050 If a method is being searched for, VALP will hold the value.
2051 If a non-method is being searched for, SYMP will hold the symbol
2052 for it.
2054 If a method is being searched for, and it is a static method,
2055 then STATICP will point to a non-zero value.
2057 Note: This function does *not* check the value of
2058 overload_resolution. Caller must check it to see whether overload
2059 resolution is permitted.
2063 find_overload_match (struct type **arg_types, int nargs,
2064 char *name, int method, int lax,
2065 struct value **objp, struct symbol *fsym,
2066 struct value **valp, struct symbol **symp,
2067 int *staticp)
2069 struct value *obj = (objp ? *objp : NULL);
2070 /* Index of best overloaded function. */
2071 int oload_champ;
2072 /* The measure for the current best match. */
2073 struct badness_vector *oload_champ_bv = NULL;
2074 struct value *temp = obj;
2075 /* For methods, the list of overloaded methods. */
2076 struct fn_field *fns_ptr = NULL;
2077 /* For non-methods, the list of overloaded function symbols. */
2078 struct symbol **oload_syms = NULL;
2079 /* Number of overloaded instances being considered. */
2080 int num_fns = 0;
2081 struct type *basetype = NULL;
2082 int boffset;
2083 int ix;
2084 int static_offset;
2085 struct cleanup *old_cleanups = NULL;
2087 const char *obj_type_name = NULL;
2088 char *func_name = NULL;
2089 enum oload_classification match_quality;
2091 /* Get the list of overloaded methods or functions. */
2092 if (method)
2094 gdb_assert (obj);
2095 obj_type_name = TYPE_NAME (value_type (obj));
2096 /* Hack: evaluate_subexp_standard often passes in a pointer
2097 value rather than the object itself, so try again. */
2098 if ((!obj_type_name || !*obj_type_name)
2099 && (TYPE_CODE (value_type (obj)) == TYPE_CODE_PTR))
2100 obj_type_name = TYPE_NAME (TYPE_TARGET_TYPE (value_type (obj)));
2102 fns_ptr = value_find_oload_method_list (&temp, name,
2103 0, &num_fns,
2104 &basetype, &boffset);
2105 if (!fns_ptr || !num_fns)
2106 error (_("Couldn't find method %s%s%s"),
2107 obj_type_name,
2108 (obj_type_name && *obj_type_name) ? "::" : "",
2109 name);
2110 /* If we are dealing with stub method types, they should have
2111 been resolved by find_method_list via
2112 value_find_oload_method_list above. */
2113 gdb_assert (TYPE_DOMAIN_TYPE (fns_ptr[0].type) != NULL);
2114 oload_champ = find_oload_champ (arg_types, nargs, method,
2115 num_fns, fns_ptr,
2116 oload_syms, &oload_champ_bv);
2118 else
2120 const char *qualified_name = SYMBOL_CPLUS_DEMANGLED_NAME (fsym);
2122 /* If we have a C++ name, try to extract just the function
2123 part. */
2124 if (qualified_name)
2125 func_name = cp_func_name (qualified_name);
2127 /* If there was no C++ name, this must be a C-style function.
2128 Just return the same symbol. Do the same if cp_func_name
2129 fails for some reason. */
2130 if (func_name == NULL)
2132 *symp = fsym;
2133 return 0;
2136 old_cleanups = make_cleanup (xfree, func_name);
2137 make_cleanup (xfree, oload_syms);
2138 make_cleanup (xfree, oload_champ_bv);
2140 oload_champ = find_oload_champ_namespace (arg_types, nargs,
2141 func_name,
2142 qualified_name,
2143 &oload_syms,
2144 &oload_champ_bv);
2147 /* Check how bad the best match is. */
2149 match_quality =
2150 classify_oload_match (oload_champ_bv, nargs,
2151 oload_method_static (method, fns_ptr,
2152 oload_champ));
2154 if (match_quality == INCOMPATIBLE)
2156 if (method)
2157 error (_("Cannot resolve method %s%s%s to any overloaded instance"),
2158 obj_type_name,
2159 (obj_type_name && *obj_type_name) ? "::" : "",
2160 name);
2161 else
2162 error (_("Cannot resolve function %s to any overloaded instance"),
2163 func_name);
2165 else if (match_quality == NON_STANDARD)
2167 if (method)
2168 warning (_("Using non-standard conversion to match method %s%s%s to supplied arguments"),
2169 obj_type_name,
2170 (obj_type_name && *obj_type_name) ? "::" : "",
2171 name);
2172 else
2173 warning (_("Using non-standard conversion to match function %s to supplied arguments"),
2174 func_name);
2177 if (method)
2179 if (staticp != NULL)
2180 *staticp = oload_method_static (method, fns_ptr, oload_champ);
2181 if (TYPE_FN_FIELD_VIRTUAL_P (fns_ptr, oload_champ))
2182 *valp = value_virtual_fn_field (&temp, fns_ptr, oload_champ,
2183 basetype, boffset);
2184 else
2185 *valp = value_fn_field (&temp, fns_ptr, oload_champ,
2186 basetype, boffset);
2188 else
2190 *symp = oload_syms[oload_champ];
2193 if (objp)
2195 struct type *temp_type = check_typedef (value_type (temp));
2196 struct type *obj_type = check_typedef (value_type (*objp));
2197 if (TYPE_CODE (temp_type) != TYPE_CODE_PTR
2198 && (TYPE_CODE (obj_type) == TYPE_CODE_PTR
2199 || TYPE_CODE (obj_type) == TYPE_CODE_REF))
2201 temp = value_addr (temp);
2203 *objp = temp;
2205 if (old_cleanups != NULL)
2206 do_cleanups (old_cleanups);
2208 switch (match_quality)
2210 case INCOMPATIBLE:
2211 return 100;
2212 case NON_STANDARD:
2213 return 10;
2214 default: /* STANDARD */
2215 return 0;
2219 /* Find the best overload match, searching for FUNC_NAME in namespaces
2220 contained in QUALIFIED_NAME until it either finds a good match or
2221 runs out of namespaces. It stores the overloaded functions in
2222 *OLOAD_SYMS, and the badness vector in *OLOAD_CHAMP_BV. The
2223 calling function is responsible for freeing *OLOAD_SYMS and
2224 *OLOAD_CHAMP_BV. */
2226 static int
2227 find_oload_champ_namespace (struct type **arg_types, int nargs,
2228 const char *func_name,
2229 const char *qualified_name,
2230 struct symbol ***oload_syms,
2231 struct badness_vector **oload_champ_bv)
2233 int oload_champ;
2235 find_oload_champ_namespace_loop (arg_types, nargs,
2236 func_name,
2237 qualified_name, 0,
2238 oload_syms, oload_champ_bv,
2239 &oload_champ);
2241 return oload_champ;
2244 /* Helper function for find_oload_champ_namespace; NAMESPACE_LEN is
2245 how deep we've looked for namespaces, and the champ is stored in
2246 OLOAD_CHAMP. The return value is 1 if the champ is a good one, 0
2247 if it isn't.
2249 It is the caller's responsibility to free *OLOAD_SYMS and
2250 *OLOAD_CHAMP_BV. */
2252 static int
2253 find_oload_champ_namespace_loop (struct type **arg_types, int nargs,
2254 const char *func_name,
2255 const char *qualified_name,
2256 int namespace_len,
2257 struct symbol ***oload_syms,
2258 struct badness_vector **oload_champ_bv,
2259 int *oload_champ)
2261 int next_namespace_len = namespace_len;
2262 int searched_deeper = 0;
2263 int num_fns = 0;
2264 struct cleanup *old_cleanups;
2265 int new_oload_champ;
2266 struct symbol **new_oload_syms;
2267 struct badness_vector *new_oload_champ_bv;
2268 char *new_namespace;
2270 if (next_namespace_len != 0)
2272 gdb_assert (qualified_name[next_namespace_len] == ':');
2273 next_namespace_len += 2;
2275 next_namespace_len +=
2276 cp_find_first_component (qualified_name + next_namespace_len);
2278 /* Initialize these to values that can safely be xfree'd. */
2279 *oload_syms = NULL;
2280 *oload_champ_bv = NULL;
2282 /* First, see if we have a deeper namespace we can search in.
2283 If we get a good match there, use it. */
2285 if (qualified_name[next_namespace_len] == ':')
2287 searched_deeper = 1;
2289 if (find_oload_champ_namespace_loop (arg_types, nargs,
2290 func_name, qualified_name,
2291 next_namespace_len,
2292 oload_syms, oload_champ_bv,
2293 oload_champ))
2295 return 1;
2299 /* If we reach here, either we're in the deepest namespace or we
2300 didn't find a good match in a deeper namespace. But, in the
2301 latter case, we still have a bad match in a deeper namespace;
2302 note that we might not find any match at all in the current
2303 namespace. (There's always a match in the deepest namespace,
2304 because this overload mechanism only gets called if there's a
2305 function symbol to start off with.) */
2307 old_cleanups = make_cleanup (xfree, *oload_syms);
2308 old_cleanups = make_cleanup (xfree, *oload_champ_bv);
2309 new_namespace = alloca (namespace_len + 1);
2310 strncpy (new_namespace, qualified_name, namespace_len);
2311 new_namespace[namespace_len] = '\0';
2312 new_oload_syms = make_symbol_overload_list (func_name,
2313 new_namespace);
2314 while (new_oload_syms[num_fns])
2315 ++num_fns;
2317 new_oload_champ = find_oload_champ (arg_types, nargs, 0, num_fns,
2318 NULL, new_oload_syms,
2319 &new_oload_champ_bv);
2321 /* Case 1: We found a good match. Free earlier matches (if any),
2322 and return it. Case 2: We didn't find a good match, but we're
2323 not the deepest function. Then go with the bad match that the
2324 deeper function found. Case 3: We found a bad match, and we're
2325 the deepest function. Then return what we found, even though
2326 it's a bad match. */
2328 if (new_oload_champ != -1
2329 && classify_oload_match (new_oload_champ_bv, nargs, 0) == STANDARD)
2331 *oload_syms = new_oload_syms;
2332 *oload_champ = new_oload_champ;
2333 *oload_champ_bv = new_oload_champ_bv;
2334 do_cleanups (old_cleanups);
2335 return 1;
2337 else if (searched_deeper)
2339 xfree (new_oload_syms);
2340 xfree (new_oload_champ_bv);
2341 discard_cleanups (old_cleanups);
2342 return 0;
2344 else
2346 gdb_assert (new_oload_champ != -1);
2347 *oload_syms = new_oload_syms;
2348 *oload_champ = new_oload_champ;
2349 *oload_champ_bv = new_oload_champ_bv;
2350 discard_cleanups (old_cleanups);
2351 return 0;
2355 /* Look for a function to take NARGS args of types ARG_TYPES. Find
2356 the best match from among the overloaded methods or functions
2357 (depending on METHOD) given by FNS_PTR or OLOAD_SYMS, respectively.
2358 The number of methods/functions in the list is given by NUM_FNS.
2359 Return the index of the best match; store an indication of the
2360 quality of the match in OLOAD_CHAMP_BV.
2362 It is the caller's responsibility to free *OLOAD_CHAMP_BV. */
2364 static int
2365 find_oload_champ (struct type **arg_types, int nargs, int method,
2366 int num_fns, struct fn_field *fns_ptr,
2367 struct symbol **oload_syms,
2368 struct badness_vector **oload_champ_bv)
2370 int ix;
2371 /* A measure of how good an overloaded instance is. */
2372 struct badness_vector *bv;
2373 /* Index of best overloaded function. */
2374 int oload_champ = -1;
2375 /* Current ambiguity state for overload resolution. */
2376 int oload_ambiguous = 0;
2377 /* 0 => no ambiguity, 1 => two good funcs, 2 => incomparable funcs. */
2379 *oload_champ_bv = NULL;
2381 /* Consider each candidate in turn. */
2382 for (ix = 0; ix < num_fns; ix++)
2384 int jj;
2385 int static_offset = oload_method_static (method, fns_ptr, ix);
2386 int nparms;
2387 struct type **parm_types;
2389 if (method)
2391 nparms = TYPE_NFIELDS (TYPE_FN_FIELD_TYPE (fns_ptr, ix));
2393 else
2395 /* If it's not a method, this is the proper place. */
2396 nparms = TYPE_NFIELDS (SYMBOL_TYPE (oload_syms[ix]));
2399 /* Prepare array of parameter types. */
2400 parm_types = (struct type **)
2401 xmalloc (nparms * (sizeof (struct type *)));
2402 for (jj = 0; jj < nparms; jj++)
2403 parm_types[jj] = (method
2404 ? (TYPE_FN_FIELD_ARGS (fns_ptr, ix)[jj].type)
2405 : TYPE_FIELD_TYPE (SYMBOL_TYPE (oload_syms[ix]),
2406 jj));
2408 /* Compare parameter types to supplied argument types. Skip
2409 THIS for static methods. */
2410 bv = rank_function (parm_types, nparms,
2411 arg_types + static_offset,
2412 nargs - static_offset);
2414 if (!*oload_champ_bv)
2416 *oload_champ_bv = bv;
2417 oload_champ = 0;
2419 else /* See whether current candidate is better or worse than
2420 previous best. */
2421 switch (compare_badness (bv, *oload_champ_bv))
2423 case 0: /* Top two contenders are equally good. */
2424 oload_ambiguous = 1;
2425 break;
2426 case 1: /* Incomparable top contenders. */
2427 oload_ambiguous = 2;
2428 break;
2429 case 2: /* New champion, record details. */
2430 *oload_champ_bv = bv;
2431 oload_ambiguous = 0;
2432 oload_champ = ix;
2433 break;
2434 case 3:
2435 default:
2436 break;
2438 xfree (parm_types);
2439 if (overload_debug)
2441 if (method)
2442 fprintf_filtered (gdb_stderr,
2443 "Overloaded method instance %s, # of parms %d\n",
2444 fns_ptr[ix].physname, nparms);
2445 else
2446 fprintf_filtered (gdb_stderr,
2447 "Overloaded function instance %s # of parms %d\n",
2448 SYMBOL_DEMANGLED_NAME (oload_syms[ix]),
2449 nparms);
2450 for (jj = 0; jj < nargs - static_offset; jj++)
2451 fprintf_filtered (gdb_stderr,
2452 "...Badness @ %d : %d\n",
2453 jj, bv->rank[jj]);
2454 fprintf_filtered (gdb_stderr,
2455 "Overload resolution champion is %d, ambiguous? %d\n",
2456 oload_champ, oload_ambiguous);
2460 return oload_champ;
2463 /* Return 1 if we're looking at a static method, 0 if we're looking at
2464 a non-static method or a function that isn't a method. */
2466 static int
2467 oload_method_static (int method, struct fn_field *fns_ptr, int index)
2469 if (method && TYPE_FN_FIELD_STATIC_P (fns_ptr, index))
2470 return 1;
2471 else
2472 return 0;
2475 /* Check how good an overload match OLOAD_CHAMP_BV represents. */
2477 static enum oload_classification
2478 classify_oload_match (struct badness_vector *oload_champ_bv,
2479 int nargs,
2480 int static_offset)
2482 int ix;
2484 for (ix = 1; ix <= nargs - static_offset; ix++)
2486 if (oload_champ_bv->rank[ix] >= 100)
2487 return INCOMPATIBLE; /* Truly mismatched types. */
2488 else if (oload_champ_bv->rank[ix] >= 10)
2489 return NON_STANDARD; /* Non-standard type conversions
2490 needed. */
2493 return STANDARD; /* Only standard conversions needed. */
2496 /* C++: return 1 is NAME is a legitimate name for the destructor of
2497 type TYPE. If TYPE does not have a destructor, or if NAME is
2498 inappropriate for TYPE, an error is signaled. */
2500 destructor_name_p (const char *name, const struct type *type)
2502 /* Destructors are a special case. */
2504 if (name[0] == '~')
2506 char *dname = type_name_no_tag (type);
2507 char *cp = strchr (dname, '<');
2508 unsigned int len;
2510 /* Do not compare the template part for template classes. */
2511 if (cp == NULL)
2512 len = strlen (dname);
2513 else
2514 len = cp - dname;
2515 if (strlen (name + 1) != len || strncmp (dname, name + 1, len) != 0)
2516 error (_("name of destructor must equal name of class"));
2517 else
2518 return 1;
2520 return 0;
2523 /* Given TYPE, a structure/union,
2524 return 1 if the component named NAME from the ultimate target
2525 structure/union is defined, otherwise, return 0. */
2528 check_field (struct type *type, const char *name)
2530 int i;
2532 for (i = TYPE_NFIELDS (type) - 1; i >= TYPE_N_BASECLASSES (type); i--)
2534 char *t_field_name = TYPE_FIELD_NAME (type, i);
2535 if (t_field_name && (strcmp_iw (t_field_name, name) == 0))
2536 return 1;
2539 /* C++: If it was not found as a data field, then try to return it
2540 as a pointer to a method. */
2542 /* Destructors are a special case. */
2543 if (destructor_name_p (name, type))
2545 int m_index, f_index;
2547 return get_destructor_fn_field (type, &m_index, &f_index);
2550 for (i = TYPE_NFN_FIELDS (type) - 1; i >= 0; --i)
2552 if (strcmp_iw (TYPE_FN_FIELDLIST_NAME (type, i), name) == 0)
2553 return 1;
2556 for (i = TYPE_N_BASECLASSES (type) - 1; i >= 0; i--)
2557 if (check_field (TYPE_BASECLASS (type, i), name))
2558 return 1;
2560 return 0;
2563 /* C++: Given an aggregate type CURTYPE, and a member name NAME,
2564 return the appropriate member (or the address of the member, if
2565 WANT_ADDRESS). This function is used to resolve user expressions
2566 of the form "DOMAIN::NAME". For more details on what happens, see
2567 the comment before value_struct_elt_for_reference. */
2569 struct value *
2570 value_aggregate_elt (struct type *curtype,
2571 char *name, int want_address,
2572 enum noside noside)
2574 switch (TYPE_CODE (curtype))
2576 case TYPE_CODE_STRUCT:
2577 case TYPE_CODE_UNION:
2578 return value_struct_elt_for_reference (curtype, 0, curtype,
2579 name, NULL,
2580 want_address, noside);
2581 case TYPE_CODE_NAMESPACE:
2582 return value_namespace_elt (curtype, name,
2583 want_address, noside);
2584 default:
2585 internal_error (__FILE__, __LINE__,
2586 _("non-aggregate type in value_aggregate_elt"));
2590 /* C++: Given an aggregate type CURTYPE, and a member name NAME,
2591 return the address of this member as a "pointer to member" type.
2592 If INTYPE is non-null, then it will be the type of the member we
2593 are looking for. This will help us resolve "pointers to member
2594 functions". This function is used to resolve user expressions of
2595 the form "DOMAIN::NAME". */
2597 static struct value *
2598 value_struct_elt_for_reference (struct type *domain, int offset,
2599 struct type *curtype, char *name,
2600 struct type *intype,
2601 int want_address,
2602 enum noside noside)
2604 struct type *t = curtype;
2605 int i;
2606 struct value *v, *result;
2608 if (TYPE_CODE (t) != TYPE_CODE_STRUCT
2609 && TYPE_CODE (t) != TYPE_CODE_UNION)
2610 error (_("Internal error: non-aggregate type to value_struct_elt_for_reference"));
2612 for (i = TYPE_NFIELDS (t) - 1; i >= TYPE_N_BASECLASSES (t); i--)
2614 char *t_field_name = TYPE_FIELD_NAME (t, i);
2616 if (t_field_name && strcmp (t_field_name, name) == 0)
2618 if (field_is_static (&TYPE_FIELD (t, i)))
2620 v = value_static_field (t, i);
2621 if (v == NULL)
2622 error (_("static field %s has been optimized out"),
2623 name);
2624 if (want_address)
2625 v = value_addr (v);
2626 return v;
2628 if (TYPE_FIELD_PACKED (t, i))
2629 error (_("pointers to bitfield members not allowed"));
2631 if (want_address)
2632 return value_from_longest
2633 (lookup_memberptr_type (TYPE_FIELD_TYPE (t, i), domain),
2634 offset + (LONGEST) (TYPE_FIELD_BITPOS (t, i) >> 3));
2635 else if (noside == EVAL_AVOID_SIDE_EFFECTS)
2636 return allocate_value (TYPE_FIELD_TYPE (t, i));
2637 else
2638 error (_("Cannot reference non-static field \"%s\""), name);
2642 /* C++: If it was not found as a data field, then try to return it
2643 as a pointer to a method. */
2645 /* Destructors are a special case. */
2646 if (destructor_name_p (name, t))
2648 error (_("member pointers to destructors not implemented yet"));
2651 /* Perform all necessary dereferencing. */
2652 while (intype && TYPE_CODE (intype) == TYPE_CODE_PTR)
2653 intype = TYPE_TARGET_TYPE (intype);
2655 for (i = TYPE_NFN_FIELDS (t) - 1; i >= 0; --i)
2657 char *t_field_name = TYPE_FN_FIELDLIST_NAME (t, i);
2658 char dem_opname[64];
2660 if (strncmp (t_field_name, "__", 2) == 0
2661 || strncmp (t_field_name, "op", 2) == 0
2662 || strncmp (t_field_name, "type", 4) == 0)
2664 if (cplus_demangle_opname (t_field_name,
2665 dem_opname, DMGL_ANSI))
2666 t_field_name = dem_opname;
2667 else if (cplus_demangle_opname (t_field_name,
2668 dem_opname, 0))
2669 t_field_name = dem_opname;
2671 if (t_field_name && strcmp (t_field_name, name) == 0)
2673 int j = TYPE_FN_FIELDLIST_LENGTH (t, i);
2674 struct fn_field *f = TYPE_FN_FIELDLIST1 (t, i);
2676 check_stub_method_group (t, i);
2678 if (intype == 0 && j > 1)
2679 error (_("non-unique member `%s' requires type instantiation"), name);
2680 if (intype)
2682 while (j--)
2683 if (TYPE_FN_FIELD_TYPE (f, j) == intype)
2684 break;
2685 if (j < 0)
2686 error (_("no member function matches that type instantiation"));
2688 else
2689 j = 0;
2691 if (TYPE_FN_FIELD_STATIC_P (f, j))
2693 struct symbol *s =
2694 lookup_symbol (TYPE_FN_FIELD_PHYSNAME (f, j),
2695 0, VAR_DOMAIN, 0);
2696 if (s == NULL)
2697 return NULL;
2699 if (want_address)
2700 return value_addr (read_var_value (s, 0));
2701 else
2702 return read_var_value (s, 0);
2705 if (TYPE_FN_FIELD_VIRTUAL_P (f, j))
2707 if (want_address)
2709 result = allocate_value
2710 (lookup_methodptr_type (TYPE_FN_FIELD_TYPE (f, j)));
2711 cplus_make_method_ptr (value_type (result),
2712 value_contents_writeable (result),
2713 TYPE_FN_FIELD_VOFFSET (f, j), 1);
2715 else if (noside == EVAL_AVOID_SIDE_EFFECTS)
2716 return allocate_value (TYPE_FN_FIELD_TYPE (f, j));
2717 else
2718 error (_("Cannot reference virtual member function \"%s\""),
2719 name);
2721 else
2723 struct symbol *s =
2724 lookup_symbol (TYPE_FN_FIELD_PHYSNAME (f, j),
2725 0, VAR_DOMAIN, 0);
2726 if (s == NULL)
2727 return NULL;
2729 v = read_var_value (s, 0);
2730 if (!want_address)
2731 result = v;
2732 else
2734 result = allocate_value (lookup_methodptr_type (TYPE_FN_FIELD_TYPE (f, j)));
2735 cplus_make_method_ptr (value_type (result),
2736 value_contents_writeable (result),
2737 value_address (v), 0);
2740 return result;
2743 for (i = TYPE_N_BASECLASSES (t) - 1; i >= 0; i--)
2745 struct value *v;
2746 int base_offset;
2748 if (BASETYPE_VIA_VIRTUAL (t, i))
2749 base_offset = 0;
2750 else
2751 base_offset = TYPE_BASECLASS_BITPOS (t, i) / 8;
2752 v = value_struct_elt_for_reference (domain,
2753 offset + base_offset,
2754 TYPE_BASECLASS (t, i),
2755 name, intype,
2756 want_address, noside);
2757 if (v)
2758 return v;
2761 /* As a last chance, pretend that CURTYPE is a namespace, and look
2762 it up that way; this (frequently) works for types nested inside
2763 classes. */
2765 return value_maybe_namespace_elt (curtype, name,
2766 want_address, noside);
2769 /* C++: Return the member NAME of the namespace given by the type
2770 CURTYPE. */
2772 static struct value *
2773 value_namespace_elt (const struct type *curtype,
2774 char *name, int want_address,
2775 enum noside noside)
2777 struct value *retval = value_maybe_namespace_elt (curtype, name,
2778 want_address,
2779 noside);
2781 if (retval == NULL)
2782 error (_("No symbol \"%s\" in namespace \"%s\"."),
2783 name, TYPE_TAG_NAME (curtype));
2785 return retval;
2788 /* A helper function used by value_namespace_elt and
2789 value_struct_elt_for_reference. It looks up NAME inside the
2790 context CURTYPE; this works if CURTYPE is a namespace or if CURTYPE
2791 is a class and NAME refers to a type in CURTYPE itself (as opposed
2792 to, say, some base class of CURTYPE). */
2794 static struct value *
2795 value_maybe_namespace_elt (const struct type *curtype,
2796 char *name, int want_address,
2797 enum noside noside)
2799 const char *namespace_name = TYPE_TAG_NAME (curtype);
2800 struct symbol *sym;
2801 struct value *result;
2803 sym = cp_lookup_symbol_namespace (namespace_name, name, NULL,
2804 get_selected_block (0),
2805 VAR_DOMAIN);
2807 if (sym == NULL)
2808 return NULL;
2809 else if ((noside == EVAL_AVOID_SIDE_EFFECTS)
2810 && (SYMBOL_CLASS (sym) == LOC_TYPEDEF))
2811 result = allocate_value (SYMBOL_TYPE (sym));
2812 else
2813 result = value_of_variable (sym, get_selected_block (0));
2815 if (result && want_address)
2816 result = value_addr (result);
2818 return result;
2821 /* Given a pointer value V, find the real (RTTI) type of the object it
2822 points to.
2824 Other parameters FULL, TOP, USING_ENC as with value_rtti_type()
2825 and refer to the values computed for the object pointed to. */
2827 struct type *
2828 value_rtti_target_type (struct value *v, int *full,
2829 int *top, int *using_enc)
2831 struct value *target;
2833 target = value_ind (v);
2835 return value_rtti_type (target, full, top, using_enc);
2838 /* Given a value pointed to by ARGP, check its real run-time type, and
2839 if that is different from the enclosing type, create a new value
2840 using the real run-time type as the enclosing type (and of the same
2841 type as ARGP) and return it, with the embedded offset adjusted to
2842 be the correct offset to the enclosed object. RTYPE is the type,
2843 and XFULL, XTOP, and XUSING_ENC are the other parameters, computed
2844 by value_rtti_type(). If these are available, they can be supplied
2845 and a second call to value_rtti_type() is avoided. (Pass RTYPE ==
2846 NULL if they're not available. */
2848 struct value *
2849 value_full_object (struct value *argp,
2850 struct type *rtype,
2851 int xfull, int xtop,
2852 int xusing_enc)
2854 struct type *real_type;
2855 int full = 0;
2856 int top = -1;
2857 int using_enc = 0;
2858 struct value *new_val;
2860 if (rtype)
2862 real_type = rtype;
2863 full = xfull;
2864 top = xtop;
2865 using_enc = xusing_enc;
2867 else
2868 real_type = value_rtti_type (argp, &full, &top, &using_enc);
2870 /* If no RTTI data, or if object is already complete, do nothing. */
2871 if (!real_type || real_type == value_enclosing_type (argp))
2872 return argp;
2874 /* If we have the full object, but for some reason the enclosing
2875 type is wrong, set it. */
2876 /* pai: FIXME -- sounds iffy */
2877 if (full)
2879 argp = value_change_enclosing_type (argp, real_type);
2880 return argp;
2883 /* Check if object is in memory */
2884 if (VALUE_LVAL (argp) != lval_memory)
2886 warning (_("Couldn't retrieve complete object of RTTI type %s; object may be in register(s)."),
2887 TYPE_NAME (real_type));
2889 return argp;
2892 /* All other cases -- retrieve the complete object. */
2893 /* Go back by the computed top_offset from the beginning of the
2894 object, adjusting for the embedded offset of argp if that's what
2895 value_rtti_type used for its computation. */
2896 new_val = value_at_lazy (real_type, value_address (argp) - top +
2897 (using_enc ? 0 : value_embedded_offset (argp)));
2898 deprecated_set_value_type (new_val, value_type (argp));
2899 set_value_embedded_offset (new_val, (using_enc
2900 ? top + value_embedded_offset (argp)
2901 : top));
2902 return new_val;
2906 /* Return the value of the local variable, if one exists.
2907 Flag COMPLAIN signals an error if the request is made in an
2908 inappropriate context. */
2910 struct value *
2911 value_of_local (const char *name, int complain)
2913 struct symbol *func, *sym;
2914 struct block *b;
2915 struct value * ret;
2916 struct frame_info *frame;
2918 if (complain)
2919 frame = get_selected_frame (_("no frame selected"));
2920 else
2922 frame = deprecated_safe_get_selected_frame ();
2923 if (frame == 0)
2924 return 0;
2927 func = get_frame_function (frame);
2928 if (!func)
2930 if (complain)
2931 error (_("no `%s' in nameless context"), name);
2932 else
2933 return 0;
2936 b = SYMBOL_BLOCK_VALUE (func);
2937 if (dict_empty (BLOCK_DICT (b)))
2939 if (complain)
2940 error (_("no args, no `%s'"), name);
2941 else
2942 return 0;
2945 /* Calling lookup_block_symbol is necessary to get the LOC_REGISTER
2946 symbol instead of the LOC_ARG one (if both exist). */
2947 sym = lookup_block_symbol (b, name, NULL, VAR_DOMAIN);
2948 if (sym == NULL)
2950 if (complain)
2951 error (_("current stack frame does not contain a variable named `%s'"),
2952 name);
2953 else
2954 return NULL;
2957 ret = read_var_value (sym, frame);
2958 if (ret == 0 && complain)
2959 error (_("`%s' argument unreadable"), name);
2960 return ret;
2963 /* C++/Objective-C: return the value of the class instance variable,
2964 if one exists. Flag COMPLAIN signals an error if the request is
2965 made in an inappropriate context. */
2967 struct value *
2968 value_of_this (int complain)
2970 if (!current_language->la_name_of_this)
2971 return 0;
2972 return value_of_local (current_language->la_name_of_this, complain);
2975 /* Create a slice (sub-string, sub-array) of ARRAY, that is LENGTH
2976 elements long, starting at LOWBOUND. The result has the same lower
2977 bound as the original ARRAY. */
2979 struct value *
2980 value_slice (struct value *array, int lowbound, int length)
2982 struct type *slice_range_type, *slice_type, *range_type;
2983 LONGEST lowerbound, upperbound;
2984 struct value *slice;
2985 struct type *array_type;
2987 array_type = check_typedef (value_type (array));
2988 if (TYPE_CODE (array_type) != TYPE_CODE_ARRAY
2989 && TYPE_CODE (array_type) != TYPE_CODE_STRING
2990 && TYPE_CODE (array_type) != TYPE_CODE_BITSTRING)
2991 error (_("cannot take slice of non-array"));
2993 range_type = TYPE_INDEX_TYPE (array_type);
2994 if (get_discrete_bounds (range_type, &lowerbound, &upperbound) < 0)
2995 error (_("slice from bad array or bitstring"));
2997 if (lowbound < lowerbound || length < 0
2998 || lowbound + length - 1 > upperbound)
2999 error (_("slice out of range"));
3001 /* FIXME-type-allocation: need a way to free this type when we are
3002 done with it. */
3003 slice_range_type = create_range_type ((struct type *) NULL,
3004 TYPE_TARGET_TYPE (range_type),
3005 lowbound,
3006 lowbound + length - 1);
3007 if (TYPE_CODE (array_type) == TYPE_CODE_BITSTRING)
3009 int i;
3011 slice_type = create_set_type ((struct type *) NULL,
3012 slice_range_type);
3013 TYPE_CODE (slice_type) = TYPE_CODE_BITSTRING;
3014 slice = value_zero (slice_type, not_lval);
3016 for (i = 0; i < length; i++)
3018 int element = value_bit_index (array_type,
3019 value_contents (array),
3020 lowbound + i);
3021 if (element < 0)
3022 error (_("internal error accessing bitstring"));
3023 else if (element > 0)
3025 int j = i % TARGET_CHAR_BIT;
3026 if (gdbarch_bits_big_endian (current_gdbarch))
3027 j = TARGET_CHAR_BIT - 1 - j;
3028 value_contents_raw (slice)[i / TARGET_CHAR_BIT] |= (1 << j);
3031 /* We should set the address, bitssize, and bitspos, so the
3032 slice can be used on the LHS, but that may require extensions
3033 to value_assign. For now, just leave as a non_lval.
3034 FIXME. */
3036 else
3038 struct type *element_type = TYPE_TARGET_TYPE (array_type);
3039 LONGEST offset =
3040 (lowbound - lowerbound) * TYPE_LENGTH (check_typedef (element_type));
3042 slice_type = create_array_type ((struct type *) NULL,
3043 element_type,
3044 slice_range_type);
3045 TYPE_CODE (slice_type) = TYPE_CODE (array_type);
3047 if (VALUE_LVAL (array) == lval_memory && value_lazy (array))
3048 slice = allocate_value_lazy (slice_type);
3049 else
3051 slice = allocate_value (slice_type);
3052 memcpy (value_contents_writeable (slice),
3053 value_contents (array) + offset,
3054 TYPE_LENGTH (slice_type));
3057 set_value_component_location (slice, array);
3058 VALUE_FRAME_ID (slice) = VALUE_FRAME_ID (array);
3059 set_value_offset (slice, value_offset (array) + offset);
3061 return slice;
3064 /* Create a value for a FORTRAN complex number. Currently most of the
3065 time values are coerced to COMPLEX*16 (i.e. a complex number
3066 composed of 2 doubles. This really should be a smarter routine
3067 that figures out precision inteligently as opposed to assuming
3068 doubles. FIXME: fmb */
3070 struct value *
3071 value_literal_complex (struct value *arg1,
3072 struct value *arg2,
3073 struct type *type)
3075 struct value *val;
3076 struct type *real_type = TYPE_TARGET_TYPE (type);
3078 val = allocate_value (type);
3079 arg1 = value_cast (real_type, arg1);
3080 arg2 = value_cast (real_type, arg2);
3082 memcpy (value_contents_raw (val),
3083 value_contents (arg1), TYPE_LENGTH (real_type));
3084 memcpy (value_contents_raw (val) + TYPE_LENGTH (real_type),
3085 value_contents (arg2), TYPE_LENGTH (real_type));
3086 return val;
3089 /* Cast a value into the appropriate complex data type. */
3091 static struct value *
3092 cast_into_complex (struct type *type, struct value *val)
3094 struct type *real_type = TYPE_TARGET_TYPE (type);
3096 if (TYPE_CODE (value_type (val)) == TYPE_CODE_COMPLEX)
3098 struct type *val_real_type = TYPE_TARGET_TYPE (value_type (val));
3099 struct value *re_val = allocate_value (val_real_type);
3100 struct value *im_val = allocate_value (val_real_type);
3102 memcpy (value_contents_raw (re_val),
3103 value_contents (val), TYPE_LENGTH (val_real_type));
3104 memcpy (value_contents_raw (im_val),
3105 value_contents (val) + TYPE_LENGTH (val_real_type),
3106 TYPE_LENGTH (val_real_type));
3108 return value_literal_complex (re_val, im_val, type);
3110 else if (TYPE_CODE (value_type (val)) == TYPE_CODE_FLT
3111 || TYPE_CODE (value_type (val)) == TYPE_CODE_INT)
3112 return value_literal_complex (val,
3113 value_zero (real_type, not_lval),
3114 type);
3115 else
3116 error (_("cannot cast non-number to complex"));
3119 void
3120 _initialize_valops (void)
3122 add_setshow_boolean_cmd ("overload-resolution", class_support,
3123 &overload_resolution, _("\
3124 Set overload resolution in evaluating C++ functions."), _("\
3125 Show overload resolution in evaluating C++ functions."),
3126 NULL, NULL,
3127 show_overload_resolution,
3128 &setlist, &showlist);
3129 overload_resolution = 1;