1 /* Definitions for values of C expressions, for GDB.
3 Copyright 1986, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994,
4 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005
5 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 2 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, write to the Free Software
21 Foundation, Inc., 59 Temple Place - Suite 330,
22 Boston, MA 02111-1307, USA. */
24 #if !defined (VALUE_H)
28 #include "frame.h" /* For struct frame_id. */
37 /* The structure which defines the type of a value. It should never
38 be possible for a program lval value to survive over a call to the
39 inferior (i.e. to be put into the history list or an internal
44 /* Type of value; either not an lval, or one of the various
45 different possible kinds of lval. */
48 /* Is it modifiable? Only relevant if lval != not_lval. */
51 /* Location of value (if lval). */
54 /* If lval == lval_memory, this is the address in the inferior.
55 If lval == lval_register, this is the byte offset into the
56 registers structure. */
59 /* Pointer to internal variable. */
60 struct internalvar
*internalvar
;
63 /* Describes offset of a value within lval of a structure in bytes.
64 If lval == lval_memory, this is an offset to the address. If
65 lval == lval_register, this is a further offset from
66 location.address within the registers structure. Note also the
67 member embedded_offset below. */
70 /* Only used for bitfields; number of bits contained in them. */
73 /* Only used for bitfields; position of start of field. For
74 BITS_BIG_ENDIAN=0 targets, it is the position of the LSB. For
75 BITS_BIG_ENDIAN=1 targets, it is the position of the MSB. */
78 /* Frame register value is relative to. This will be described in
79 the lval enum above as "lval_register". */
80 struct frame_id frame_id
;
82 /* Type of the value. */
85 /* If a value represents a C++ object, then the `type' field gives
86 the object's compile-time type. If the object actually belongs
87 to some class derived from `type', perhaps with other base
88 classes and additional members, then `type' is just a subobject
89 of the real thing, and the full object is probably larger than
92 If `type' is a dynamic class (i.e. one with a vtable), then GDB
93 can actually determine the object's run-time type by looking at
94 the run-time type information in the vtable. When this
95 information is available, we may elect to read in the entire
96 object, for several reasons:
98 - When printing the value, the user would probably rather see the
99 full object, not just the limited portion apparent from the
102 - If `type' has virtual base classes, then even printing `type'
103 alone may require reaching outside the `type' portion of the
104 object to wherever the virtual base class has been stored.
106 When we store the entire object, `enclosing_type' is the run-time
107 type -- the complete object -- and `embedded_offset' is the
108 offset of `type' within that larger type, in bytes. The
109 value_contents() macro takes `embedded_offset' into account, so
110 most GDB code continues to see the `type' portion of the value,
111 just as the inferior would.
113 If `type' is a pointer to an object, then `enclosing_type' is a
114 pointer to the object's run-time type, and `pointed_to_offset' is
115 the offset in bytes from the full object to the pointed-to object
116 -- that is, the value `embedded_offset' would have if we followed
117 the pointer and fetched the complete object. (I don't really see
118 the point. Why not just determine the run-time type when you
119 indirect, and avoid the special case? The contents don't matter
120 until you indirect anyway.)
122 If we're not doing anything fancy, `enclosing_type' is equal to
123 `type', and `embedded_offset' is zero, so everything works
125 struct type
*enclosing_type
;
127 int pointed_to_offset
;
129 /* Values are stored in a chain, so that they can be deleted easily
130 over calls to the inferior. Values assigned to internal
131 variables or put into the value history are taken off this
135 /* Register number if the value is from a register. */
138 /* If zero, contents of this value are in the contents field. If
139 nonzero, contents are in inferior memory at address in the
140 location.address field plus the offset field (and the lval field
141 should be lval_memory).
143 WARNING: This field is used by the code which handles watchpoints
144 (see breakpoint.c) to decide whether a particular value can be
145 watched by hardware watchpoints. If the lazy flag is set for
146 some member of a value chain, it is assumed that this member of
147 the chain doesn't need to be watched as part of watching the
148 value itself. This is how GDB avoids watching the entire struct
149 or array when the user wants to watch a single struct member or
150 array element. If you ever change the way lazy flag is set and
151 reset, be sure to consider this use as well! */
154 /* If nonzero, this is the value of a variable which does not
155 actually exist in the program. */
158 /* Actual contents of the value. For use of this value; setting it
159 uses the stuff above. Not valid if lazy is nonzero. Target
160 byte-order. We force it to be aligned properly for any possible
161 value. Note that a value therefore extends beyond what is
165 bfd_byte contents
[1];
166 DOUBLEST force_doublest_align
;
167 LONGEST force_longest_align
;
168 CORE_ADDR force_core_addr_align
;
169 void *force_pointer_align
;
171 /* Do not add any new members here -- contents above will trash
176 extern struct type
*value_type (struct value
*);
177 /* This is being used to change the type of an existing value, that
178 code should instead be creating a new value with the changed type
179 (but possibly shared content). */
180 extern void deprecated_set_value_type (struct value
*value
,
182 extern int value_bitsize (struct value
*);
183 extern int value_bitpos (struct value
*);
184 extern int value_offset (struct value
*);
186 /* The comment from "struct value" reads: ``Is it modifiable? Only
187 relevant if lval != not_lval.''. Shouldn't the value instead be
188 not_lval and be done with it? */
189 extern int deprecated_value_modifiable (struct value
*value
);
190 extern void deprecated_set_value_modifiable (struct value
*value
,
193 extern struct type
*value_enclosing_type (struct value
*);
194 extern int value_lazy (struct value
*);
195 extern void set_value_lazy (struct value
*value
, int val
);
197 /* value_contents() and value_contents_raw() both return the address
198 of the gdb buffer used to hold a copy of the contents of the lval.
199 value_contents() is used when the contents of the buffer are needed
200 -- it uses value_fetch_lazy() to load the buffer from the process
201 being debugged if it hasn't already been loaded
202 (value_contents_writeable() is used when a writeable but fetched
203 buffer is required).. value_contents_raw() is used when data is
204 being stored into the buffer, or when it is certain that the
205 contents of the buffer are valid.
207 Note: The contents pointer is adjusted by the offset required to
208 get to the real subobject, if the value happens to represent
209 something embedded in a larger run-time object. */
211 extern bfd_byte
*value_contents_raw (struct value
*);
212 extern const bfd_byte
*value_contents (struct value
*);
213 extern bfd_byte
*value_contents_writeable (struct value
*);
215 /* The ALL variants of the above two macros do not adjust the returned
216 pointer by the embedded_offset value. */
218 extern bfd_byte
*value_contents_all_raw (struct value
*);
219 extern const bfd_byte
*value_contents_all (struct value
*);
221 extern int value_fetch_lazy (struct value
*val
);
223 extern int value_optimized_out (struct value
*value
);
224 extern void set_value_optimized_out (struct value
*value
, int val
);
225 extern int value_embedded_offset (struct value
*value
);
226 extern void set_value_embedded_offset (struct value
*value
, int val
);
227 extern int value_pointed_to_offset (struct value
*value
);
228 extern void set_value_pointed_to_offset (struct value
*value
, int val
);
230 /* While the following fields are per- VALUE .CONTENT .PIECE (i.e., a
231 single value might have multiple LVALs), this hacked interface is
232 limited to just the first PIECE. Expect further change. */
233 extern enum lval_type
*deprecated_value_lval_hack (struct value
*);
234 #define VALUE_LVAL(val) (*deprecated_value_lval_hack (val))
235 extern CORE_ADDR
*deprecated_value_address_hack (struct value
*);
236 #define VALUE_ADDRESS(val) (*deprecated_value_address_hack (val))
237 extern struct internalvar
**deprecated_value_internalvar_hack (struct value
*);
238 #define VALUE_INTERNALVAR(val) (*deprecated_value_internalvar_hack (val))
239 extern struct frame_id
*deprecated_value_frame_id_hack (struct value
*);
240 #define VALUE_FRAME_ID(val) (*deprecated_value_frame_id_hack (val))
241 extern short *deprecated_value_regnum_hack (struct value
*);
242 #define VALUE_REGNUM(val) (*deprecated_value_regnum_hack (val))
244 /* Convert a REF to the object referenced. */
246 extern struct value
*coerce_ref (struct value
*value
);
248 /* If ARG is an array, convert it to a pointer.
249 If ARG is an enum, convert it to an integer.
250 If ARG is a function, convert it to a function pointer.
252 References are dereferenced. */
254 extern struct value
*coerce_array (struct value
*value
);
255 extern struct value
*coerce_number (struct value
*value
);
257 /* If ARG is an enum, convert it to an integer. */
259 extern struct value
*coerce_enum (struct value
*value
);
261 /* Internal variables (variables for convenience of use of debugger)
262 are recorded as a chain of these structures. */
266 struct internalvar
*next
;
271 /* Pointer to member function. Depends on compiler implementation. */
273 #define METHOD_PTR_IS_VIRTUAL(ADDR) ((ADDR) & 0x80000000)
274 #define METHOD_PTR_FROM_VOFFSET(OFFSET) (0x80000000 + (OFFSET))
275 #define METHOD_PTR_TO_VOFFSET(ADDR) (~0x80000000 & (ADDR))
279 #include "gdbtypes.h"
280 #include "expression.h"
285 extern void print_address_demangle (CORE_ADDR
, struct ui_file
*, int);
287 extern LONGEST
value_as_long (struct value
*val
);
288 extern DOUBLEST
value_as_double (struct value
*val
);
289 extern CORE_ADDR
value_as_address (struct value
*val
);
291 extern LONGEST
unpack_long (struct type
*type
, const char *valaddr
);
292 extern DOUBLEST
unpack_double (struct type
*type
, const char *valaddr
,
294 extern CORE_ADDR
unpack_pointer (struct type
*type
, const char *valaddr
);
295 extern LONGEST
unpack_field_as_long (struct type
*type
, const char *valaddr
,
298 extern struct value
*value_from_longest (struct type
*type
, LONGEST num
);
299 extern struct value
*value_from_pointer (struct type
*type
, CORE_ADDR addr
);
300 extern struct value
*value_from_double (struct type
*type
, DOUBLEST num
);
301 extern struct value
*value_from_string (char *string
);
303 extern struct value
*value_at (struct type
*type
, CORE_ADDR addr
);
304 extern struct value
*value_at_lazy (struct type
*type
, CORE_ADDR addr
);
306 extern struct value
*value_from_register (struct type
*type
, int regnum
,
307 struct frame_info
*frame
);
309 extern struct value
*value_of_variable (struct symbol
*var
, struct block
*b
);
311 extern struct value
*value_of_register (int regnum
, struct frame_info
*frame
);
313 extern int symbol_read_needs_frame (struct symbol
*);
315 extern struct value
*read_var_value (struct symbol
*var
,
316 struct frame_info
*frame
);
318 extern struct value
*locate_var_value (struct symbol
*var
,
319 struct frame_info
*frame
);
321 extern struct value
*allocate_value (struct type
*type
);
323 extern struct value
*allocate_repeat_value (struct type
*type
, int count
);
325 extern struct value
*value_change_enclosing_type (struct value
*val
,
326 struct type
*new_type
);
328 extern struct value
*value_mark (void);
330 extern void value_free_to_mark (struct value
*mark
);
332 extern struct value
*value_string (char *ptr
, int len
);
333 extern struct value
*value_bitstring (char *ptr
, int len
);
335 extern struct value
*value_array (int lowbound
, int highbound
,
336 struct value
**elemvec
);
338 extern struct value
*value_concat (struct value
*arg1
, struct value
*arg2
);
340 extern struct value
*value_binop (struct value
*arg1
, struct value
*arg2
,
343 extern struct value
*value_add (struct value
*arg1
, struct value
*arg2
);
345 extern struct value
*value_sub (struct value
*arg1
, struct value
*arg2
);
347 extern struct value
*value_coerce_array (struct value
*arg1
);
349 extern struct value
*value_coerce_function (struct value
*arg1
);
351 extern struct value
*value_ind (struct value
*arg1
);
353 extern struct value
*value_addr (struct value
*arg1
);
355 extern struct value
*value_assign (struct value
*toval
,
356 struct value
*fromval
);
358 extern struct value
*value_neg (struct value
*arg1
);
360 extern struct value
*value_complement (struct value
*arg1
);
362 extern struct value
*value_struct_elt (struct value
**argp
,
364 char *name
, int *static_memfuncp
,
367 extern struct value
*value_aggregate_elt (struct type
*curtype
,
368 char *name
, enum noside noside
);
370 extern struct value
*value_static_field (struct type
*type
, int fieldno
);
372 extern struct fn_field
*value_find_oload_method_list (struct value
**, char *,
374 struct type
**, int *);
376 extern int find_overload_match (struct type
**arg_types
, int nargs
,
377 char *name
, int method
, int lax
,
378 struct value
**objp
, struct symbol
*fsym
,
379 struct value
**valp
, struct symbol
**symp
,
382 extern struct value
*value_field (struct value
*arg1
, int fieldno
);
384 extern struct value
*value_primitive_field (struct value
*arg1
, int offset
,
386 struct type
*arg_type
);
389 extern struct type
*value_rtti_target_type (struct value
*, int *, int *,
392 extern struct value
*value_full_object (struct value
*, struct type
*, int,
395 extern struct value
*value_cast (struct type
*type
, struct value
*arg2
);
397 extern struct value
*value_zero (struct type
*type
, enum lval_type lv
);
399 extern struct value
*value_repeat (struct value
*arg1
, int count
);
401 extern struct value
*value_subscript (struct value
*array
, struct value
*idx
);
403 extern struct value
*register_value_being_returned (struct type
*valtype
,
404 struct regcache
*retbuf
);
406 extern struct value
*value_in (struct value
*element
, struct value
*set
);
408 extern int value_bit_index (struct type
*type
, const bfd_byte
*addr
,
411 extern int using_struct_return (struct type
*value_type
, int gcc_p
);
413 extern struct value
*evaluate_expression (struct expression
*exp
);
415 extern struct value
*evaluate_type (struct expression
*exp
);
417 extern struct value
*evaluate_subexp_with_coercion (struct expression
*,
420 extern struct value
*parse_and_eval (char *exp
);
422 extern struct value
*parse_to_comma_and_eval (char **expp
);
424 extern struct type
*parse_and_eval_type (char *p
, int length
);
426 extern CORE_ADDR
parse_and_eval_address (char *exp
);
428 extern CORE_ADDR
parse_and_eval_address_1 (char **expptr
);
430 extern LONGEST
parse_and_eval_long (char *exp
);
432 extern struct value
*access_value_history (int num
);
434 extern struct value
*value_of_internalvar (struct internalvar
*var
);
436 extern void set_internalvar (struct internalvar
*var
, struct value
*val
);
438 extern void set_internalvar_component (struct internalvar
*var
,
440 int bitpos
, int bitsize
,
441 struct value
*newvalue
);
443 extern struct internalvar
*lookup_internalvar (char *name
);
445 extern int value_equal (struct value
*arg1
, struct value
*arg2
);
447 extern int value_less (struct value
*arg1
, struct value
*arg2
);
449 extern int value_logical_not (struct value
*arg1
);
453 extern struct value
*value_of_this (int complain
);
455 extern struct value
*value_x_binop (struct value
*arg1
, struct value
*arg2
,
457 enum exp_opcode otherop
,
460 extern struct value
*value_x_unop (struct value
*arg1
, enum exp_opcode op
,
463 extern struct value
*value_fn_field (struct value
**arg1p
, struct fn_field
*f
,
464 int j
, struct type
*type
, int offset
);
466 extern int binop_user_defined_p (enum exp_opcode op
, struct value
*arg1
,
469 extern int unop_user_defined_p (enum exp_opcode op
, struct value
*arg1
);
471 extern int destructor_name_p (const char *name
, const struct type
*type
);
473 #define value_free(val) xfree (val)
475 extern void free_all_values (void);
477 extern void release_value (struct value
*val
);
479 extern int record_latest_value (struct value
*val
);
481 extern void modify_field (char *addr
, LONGEST fieldval
, int bitpos
,
484 extern void type_print (struct type
*type
, char *varstring
,
485 struct ui_file
*stream
, int show
);
487 extern char *baseclass_addr (struct type
*type
, int index
, char *valaddr
,
488 struct value
**valuep
, int *errp
);
490 extern void print_longest (struct ui_file
*stream
, int format
,
491 int use_local
, LONGEST val
);
493 extern void print_floating (const bfd_byte
*valaddr
, struct type
*type
,
494 struct ui_file
*stream
);
496 extern int value_print (struct value
*val
, struct ui_file
*stream
, int format
,
497 enum val_prettyprint pretty
);
499 extern void value_print_array_elements (struct value
*val
,
500 struct ui_file
*stream
, int format
,
501 enum val_prettyprint pretty
);
503 extern struct value
*value_release_to_mark (struct value
*mark
);
505 extern int val_print (struct type
*type
, const bfd_byte
*valaddr
,
506 int embedded_offset
, CORE_ADDR address
,
507 struct ui_file
*stream
, int format
,
508 int deref_ref
, int recurse
,
509 enum val_prettyprint pretty
);
511 extern int val_print_string (CORE_ADDR addr
, int len
, int width
,
512 struct ui_file
*stream
);
514 extern void print_variable_value (struct symbol
*var
,
515 struct frame_info
*frame
,
516 struct ui_file
*stream
);
518 extern int check_field (struct value
*, const char *);
520 extern void typedef_print (struct type
*type
, struct symbol
*news
,
521 struct ui_file
*stream
);
523 extern char *internalvar_name (struct internalvar
*var
);
525 extern void clear_value_history (void);
527 extern void clear_internalvars (void);
531 extern struct value
*value_copy (struct value
*);
535 extern struct value
*varying_to_slice (struct value
*);
537 extern struct value
*value_slice (struct value
*, int, int);
539 extern struct value
*value_literal_complex (struct value
*, struct value
*,
542 extern void find_rt_vbase_offset (struct type
*, struct type
*,
543 const bfd_byte
*, int, int *, int *);
545 extern struct value
*find_function_in_inferior (const char *);
547 extern struct value
*value_allocate_space_in_inferior (int);
549 extern struct value
*value_of_local (const char *name
, int complain
);
551 #endif /* !defined (VALUE_H) */