1 /* Definitions for values of C expressions, 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 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 #if !defined (VALUE_H)
26 #include "frame.h" /* For struct frame_id. */
35 struct value_print_options
;
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 /* Needed if another module needs to maintain its own list of values. */
46 void value_prepend_to_list (struct value
**head
, struct value
*val
);
47 void value_remove_from_list (struct value
**head
, struct value
*val
);
49 /* Values are stored in a chain, so that they can be deleted easily
50 over calls to the inferior. Values assigned to internal variables,
51 put into the value history or exposed to Python are taken off this
54 struct value
*value_next (struct value
*);
56 /* Type of the value. */
58 extern struct type
*value_type (struct value
*);
60 /* This is being used to change the type of an existing value, that
61 code should instead be creating a new value with the changed type
62 (but possibly shared content). */
64 extern void deprecated_set_value_type (struct value
*value
,
67 /* Only used for bitfields; number of bits contained in them. */
69 extern int value_bitsize (struct value
*);
70 extern void set_value_bitsize (struct value
*, int bit
);
72 /* Only used for bitfields; position of start of field. For
73 gdbarch_bits_big_endian=0 targets, it is the position of the LSB. For
74 gdbarch_bits_big_endian=1 targets, it is the position of the MSB. */
76 extern int value_bitpos (struct value
*);
77 extern void set_value_bitpos (struct value
*, int bit
);
79 /* Describes offset of a value within lval of a structure in bytes.
80 If lval == lval_memory, this is an offset to the address. If lval
81 == lval_register, this is a further offset from location.address
82 within the registers structure. Note also the member
83 embedded_offset below. */
85 extern int value_offset (struct value
*);
86 extern void set_value_offset (struct value
*, int offset
);
88 /* The comment from "struct value" reads: ``Is it modifiable? Only
89 relevant if lval != not_lval.''. Shouldn't the value instead be
90 not_lval and be done with it? */
92 extern int deprecated_value_modifiable (struct value
*value
);
93 extern void deprecated_set_value_modifiable (struct value
*value
,
96 /* If a value represents a C++ object, then the `type' field gives the
97 object's compile-time type. If the object actually belongs to some
98 class derived from `type', perhaps with other base classes and
99 additional members, then `type' is just a subobject of the real
100 thing, and the full object is probably larger than `type' would
103 If `type' is a dynamic class (i.e. one with a vtable), then GDB can
104 actually determine the object's run-time type by looking at the
105 run-time type information in the vtable. When this information is
106 available, we may elect to read in the entire object, for several
109 - When printing the value, the user would probably rather see the
110 full object, not just the limited portion apparent from the
113 - If `type' has virtual base classes, then even printing `type'
114 alone may require reaching outside the `type' portion of the
115 object to wherever the virtual base class has been stored.
117 When we store the entire object, `enclosing_type' is the run-time
118 type -- the complete object -- and `embedded_offset' is the offset
119 of `type' within that larger type, in bytes. The value_contents()
120 macro takes `embedded_offset' into account, so most GDB code
121 continues to see the `type' portion of the value, just as the
124 If `type' is a pointer to an object, then `enclosing_type' is a
125 pointer to the object's run-time type, and `pointed_to_offset' is
126 the offset in bytes from the full object to the pointed-to object
127 -- that is, the value `embedded_offset' would have if we followed
128 the pointer and fetched the complete object. (I don't really see
129 the point. Why not just determine the run-time type when you
130 indirect, and avoid the special case? The contents don't matter
131 until you indirect anyway.)
133 If we're not doing anything fancy, `enclosing_type' is equal to
134 `type', and `embedded_offset' is zero, so everything works
137 extern struct type
*value_enclosing_type (struct value
*);
138 extern struct value
*value_change_enclosing_type (struct value
*val
,
139 struct type
*new_type
);
140 extern int value_pointed_to_offset (struct value
*value
);
141 extern void set_value_pointed_to_offset (struct value
*value
, int val
);
142 extern int value_embedded_offset (struct value
*value
);
143 extern void set_value_embedded_offset (struct value
*value
, int val
);
145 /* If zero, contents of this value are in the contents field. If
146 nonzero, contents are in inferior. If the lval field is lval_memory,
147 the contents are in inferior memory at location.address plus offset.
148 The lval field may also be lval_register.
150 WARNING: This field is used by the code which handles watchpoints
151 (see breakpoint.c) to decide whether a particular value can be
152 watched by hardware watchpoints. If the lazy flag is set for some
153 member of a value chain, it is assumed that this member of the
154 chain doesn't need to be watched as part of watching the value
155 itself. This is how GDB avoids watching the entire struct or array
156 when the user wants to watch a single struct member or array
157 element. If you ever change the way lazy flag is set and reset, be
158 sure to consider this use as well! */
160 extern int value_lazy (struct value
*);
161 extern void set_value_lazy (struct value
*value
, int val
);
163 /* value_contents() and value_contents_raw() both return the address
164 of the gdb buffer used to hold a copy of the contents of the lval.
165 value_contents() is used when the contents of the buffer are needed
166 -- it uses value_fetch_lazy() to load the buffer from the process
167 being debugged if it hasn't already been loaded
168 (value_contents_writeable() is used when a writeable but fetched
169 buffer is required).. value_contents_raw() is used when data is
170 being stored into the buffer, or when it is certain that the
171 contents of the buffer are valid.
173 Note: The contents pointer is adjusted by the offset required to
174 get to the real subobject, if the value happens to represent
175 something embedded in a larger run-time object. */
177 extern gdb_byte
*value_contents_raw (struct value
*);
179 /* Actual contents of the value. For use of this value; setting it
180 uses the stuff above. Not valid if lazy is nonzero. Target
181 byte-order. We force it to be aligned properly for any possible
182 value. Note that a value therefore extends beyond what is
185 extern const gdb_byte
*value_contents (struct value
*);
186 extern gdb_byte
*value_contents_writeable (struct value
*);
188 /* The ALL variants of the above two macros do not adjust the returned
189 pointer by the embedded_offset value. */
191 extern gdb_byte
*value_contents_all_raw (struct value
*);
192 extern const gdb_byte
*value_contents_all (struct value
*);
194 extern int value_fetch_lazy (struct value
*val
);
195 extern int value_contents_equal (struct value
*val1
, struct value
*val2
);
197 /* If nonzero, this is the value of a variable which does not actually
198 exist in the program. */
199 extern int value_optimized_out (struct value
*value
);
200 extern void set_value_optimized_out (struct value
*value
, int val
);
202 /* Set or return field indicating whether a variable is initialized or
203 not, based on debugging information supplied by the compiler.
204 1 = initialized; 0 = uninitialized. */
205 extern int value_initialized (struct value
*);
206 extern void set_value_initialized (struct value
*, int);
208 /* While the following fields are per- VALUE .CONTENT .PIECE (i.e., a
209 single value might have multiple LVALs), this hacked interface is
210 limited to just the first PIECE. Expect further change. */
211 /* Type of value; either not an lval, or one of the various different
212 possible kinds of lval. */
213 extern enum lval_type
*deprecated_value_lval_hack (struct value
*);
214 #define VALUE_LVAL(val) (*deprecated_value_lval_hack (val))
216 /* If lval == lval_memory, this is the address in the inferior. If
217 lval == lval_register, this is the byte offset into the registers
219 extern CORE_ADDR
*deprecated_value_address_hack (struct value
*);
220 #define VALUE_ADDRESS(val) (*deprecated_value_address_hack (val))
222 /* Pointer to internal variable. */
223 extern struct internalvar
**deprecated_value_internalvar_hack (struct value
*);
224 #define VALUE_INTERNALVAR(val) (*deprecated_value_internalvar_hack (val))
226 /* Frame register value is relative to. This will be described in the
227 lval enum above as "lval_register". */
228 extern struct frame_id
*deprecated_value_frame_id_hack (struct value
*);
229 #define VALUE_FRAME_ID(val) (*deprecated_value_frame_id_hack (val))
231 /* Register number if the value is from a register. */
232 extern short *deprecated_value_regnum_hack (struct value
*);
233 #define VALUE_REGNUM(val) (*deprecated_value_regnum_hack (val))
235 /* Convert a REF to the object referenced. */
237 extern struct value
*coerce_ref (struct value
*value
);
239 /* If ARG is an array, convert it to a pointer.
240 If ARG is a function, convert it to a function pointer.
242 References are dereferenced. */
244 extern struct value
*coerce_array (struct value
*value
);
246 /* Internal variables (variables for convenience of use of debugger)
247 are recorded as a chain of these structures. */
251 struct internalvar
*next
;
260 #include "gdbtypes.h"
261 #include "expression.h"
266 extern void print_address_demangle (CORE_ADDR
, struct ui_file
*, int);
268 extern LONGEST
value_as_long (struct value
*val
);
269 extern DOUBLEST
value_as_double (struct value
*val
);
270 extern CORE_ADDR
value_as_address (struct value
*val
);
272 extern LONGEST
unpack_long (struct type
*type
, const gdb_byte
*valaddr
);
273 extern DOUBLEST
unpack_double (struct type
*type
, const gdb_byte
*valaddr
,
275 extern CORE_ADDR
unpack_pointer (struct type
*type
, const gdb_byte
*valaddr
);
276 extern LONGEST
unpack_field_as_long (struct type
*type
,
277 const gdb_byte
*valaddr
,
280 extern void pack_long (gdb_byte
*buf
, struct type
*type
, LONGEST num
);
282 extern struct value
*value_from_longest (struct type
*type
, LONGEST num
);
283 extern struct value
*value_from_pointer (struct type
*type
, CORE_ADDR addr
);
284 extern struct value
*value_from_double (struct type
*type
, DOUBLEST num
);
285 extern struct value
*value_from_decfloat (struct type
*type
,
286 const gdb_byte
*decbytes
);
287 extern struct value
*value_from_string (char *string
);
289 extern struct value
*value_at (struct type
*type
, CORE_ADDR addr
);
290 extern struct value
*value_at_lazy (struct type
*type
, CORE_ADDR addr
);
292 extern struct value
*value_from_contents_and_address (struct type
*,
296 extern struct value
*default_value_from_register (struct type
*type
,
298 struct frame_info
*frame
);
300 extern struct value
*value_from_register (struct type
*type
, int regnum
,
301 struct frame_info
*frame
);
303 extern CORE_ADDR
address_from_register (struct type
*type
, int regnum
,
304 struct frame_info
*frame
);
306 extern struct value
*value_of_variable (struct symbol
*var
, struct block
*b
);
308 extern struct value
*value_of_register (int regnum
, struct frame_info
*frame
);
310 struct value
*value_of_register_lazy (struct frame_info
*frame
, int regnum
);
312 extern int symbol_read_needs_frame (struct symbol
*);
314 extern struct value
*read_var_value (struct symbol
*var
,
315 struct frame_info
*frame
);
317 extern struct value
*locate_var_value (struct symbol
*var
,
318 struct frame_info
*frame
);
320 extern struct value
*allocate_value (struct type
*type
);
322 extern struct value
*allocate_repeat_value (struct type
*type
, int count
);
324 extern struct value
*value_mark (void);
326 extern void value_free_to_mark (struct value
*mark
);
328 extern struct value
*value_string (char *ptr
, int len
);
329 extern struct value
*value_bitstring (char *ptr
, int len
);
331 extern struct value
*value_array (int lowbound
, int highbound
,
332 struct value
**elemvec
);
334 extern struct value
*value_concat (struct value
*arg1
, struct value
*arg2
);
336 extern struct value
*value_binop (struct value
*arg1
, struct value
*arg2
,
339 extern struct value
*value_ptradd (struct value
*arg1
, struct value
*arg2
);
341 extern struct value
*value_ptrsub (struct value
*arg1
, struct value
*arg2
);
343 extern LONGEST
value_ptrdiff (struct value
*arg1
, struct value
*arg2
);
345 extern int value_must_coerce_to_target (struct value
*arg1
);
347 extern struct value
*value_coerce_to_target (struct value
*arg1
);
349 extern struct value
*value_coerce_array (struct value
*arg1
);
351 extern struct value
*value_coerce_function (struct value
*arg1
);
353 extern struct value
*value_ind (struct value
*arg1
);
355 extern struct value
*value_addr (struct value
*arg1
);
357 extern struct value
*value_ref (struct value
*arg1
);
359 extern struct value
*value_assign (struct value
*toval
,
360 struct value
*fromval
);
362 extern struct value
*value_pos (struct value
*arg1
);
364 extern struct value
*value_neg (struct value
*arg1
);
366 extern struct value
*value_complement (struct value
*arg1
);
368 extern struct value
*value_struct_elt (struct value
**argp
,
370 char *name
, int *static_memfuncp
,
373 extern struct value
*value_aggregate_elt (struct type
*curtype
,
378 extern struct value
*value_static_field (struct type
*type
, int fieldno
);
380 extern struct fn_field
*value_find_oload_method_list (struct value
**, char *,
382 struct type
**, int *);
384 extern int find_overload_match (struct type
**arg_types
, int nargs
,
385 char *name
, int method
, int lax
,
386 struct value
**objp
, struct symbol
*fsym
,
387 struct value
**valp
, struct symbol
**symp
,
390 extern struct value
*value_field (struct value
*arg1
, int fieldno
);
392 extern struct value
*value_primitive_field (struct value
*arg1
, int offset
,
394 struct type
*arg_type
);
397 extern struct type
*value_rtti_target_type (struct value
*, int *, int *,
400 extern struct value
*value_full_object (struct value
*, struct type
*, int,
403 extern struct value
*value_cast_pointers (struct type
*, struct value
*);
405 extern struct value
*value_cast (struct type
*type
, struct value
*arg2
);
407 extern struct value
*value_zero (struct type
*type
, enum lval_type lv
);
409 extern struct value
*value_one (struct type
*type
, enum lval_type lv
);
411 extern struct value
*value_repeat (struct value
*arg1
, int count
);
413 extern struct value
*value_subscript (struct value
*array
, struct value
*idx
);
415 extern struct value
*value_bitstring_subscript (struct type
*type
,
416 struct value
*bitstring
,
419 extern struct value
*register_value_being_returned (struct type
*valtype
,
420 struct regcache
*retbuf
);
422 extern int value_in (struct value
*element
, struct value
*set
);
424 extern int value_bit_index (struct type
*type
, const gdb_byte
*addr
,
427 extern int using_struct_return (struct type
*func_type
,
428 struct type
*value_type
);
430 extern struct value
*evaluate_expression (struct expression
*exp
);
432 extern struct value
*evaluate_type (struct expression
*exp
);
434 extern struct value
*evaluate_subexpression_type (struct expression
*exp
,
437 extern char *extract_field_op (struct expression
*exp
, int *subexp
);
439 extern struct value
*evaluate_subexp_with_coercion (struct expression
*,
442 extern struct value
*parse_and_eval (char *exp
);
444 extern struct value
*parse_to_comma_and_eval (char **expp
);
446 extern struct type
*parse_and_eval_type (char *p
, int length
);
448 extern CORE_ADDR
parse_and_eval_address (char *exp
);
450 extern CORE_ADDR
parse_and_eval_address_1 (char **expptr
);
452 extern LONGEST
parse_and_eval_long (char *exp
);
454 extern void unop_promote (const struct language_defn
*language
,
455 struct gdbarch
*gdbarch
,
456 struct value
**arg1
);
458 extern void binop_promote (const struct language_defn
*language
,
459 struct gdbarch
*gdbarch
,
460 struct value
**arg1
, struct value
**arg2
);
462 extern struct value
*access_value_history (int num
);
464 extern struct value
*value_of_internalvar (struct internalvar
*var
);
466 extern void set_internalvar (struct internalvar
*var
, struct value
*val
);
468 extern void set_internalvar_component (struct internalvar
*var
,
470 int bitpos
, int bitsize
,
471 struct value
*newvalue
);
473 extern struct internalvar
*lookup_only_internalvar (char *name
);
475 extern struct internalvar
*create_internalvar (char *name
);
477 extern struct internalvar
*lookup_internalvar (char *name
);
479 extern int value_equal (struct value
*arg1
, struct value
*arg2
);
481 extern int value_less (struct value
*arg1
, struct value
*arg2
);
483 extern int value_logical_not (struct value
*arg1
);
487 extern struct value
*value_of_this (int complain
);
489 extern struct value
*value_x_binop (struct value
*arg1
, struct value
*arg2
,
491 enum exp_opcode otherop
,
494 extern struct value
*value_x_unop (struct value
*arg1
, enum exp_opcode op
,
497 extern struct value
*value_fn_field (struct value
**arg1p
, struct fn_field
*f
,
498 int j
, struct type
*type
, int offset
);
500 extern int binop_user_defined_p (enum exp_opcode op
, struct value
*arg1
,
503 extern int unop_user_defined_p (enum exp_opcode op
, struct value
*arg1
);
505 extern int destructor_name_p (const char *name
, const struct type
*type
);
507 #define value_free(val) xfree (val)
509 extern void free_all_values (void);
511 extern void release_value (struct value
*val
);
513 extern int record_latest_value (struct value
*val
);
515 extern void modify_field (gdb_byte
*addr
, LONGEST fieldval
, int bitpos
,
518 extern void type_print (struct type
*type
, char *varstring
,
519 struct ui_file
*stream
, int show
);
521 extern gdb_byte
*baseclass_addr (struct type
*type
, int index
,
523 struct value
**valuep
, int *errp
);
525 extern void print_longest (struct ui_file
*stream
, int format
,
526 int use_local
, LONGEST val
);
528 extern void print_floating (const gdb_byte
*valaddr
, struct type
*type
,
529 struct ui_file
*stream
);
531 extern void print_decimal_floating (const gdb_byte
*valaddr
, struct type
*type
,
532 struct ui_file
*stream
);
534 extern int value_print (struct value
*val
, struct ui_file
*stream
,
535 const struct value_print_options
*options
);
537 extern void value_print_array_elements (struct value
*val
,
538 struct ui_file
*stream
, int format
,
539 enum val_prettyprint pretty
);
541 extern struct value
*value_release_to_mark (struct value
*mark
);
543 extern int val_print (struct type
*type
, const gdb_byte
*valaddr
,
544 int embedded_offset
, CORE_ADDR address
,
545 struct ui_file
*stream
, int recurse
,
546 const struct value_print_options
*options
,
547 const struct language_defn
*language
);
549 extern int common_val_print (struct value
*val
,
550 struct ui_file
*stream
, int recurse
,
551 const struct value_print_options
*options
,
552 const struct language_defn
*language
);
554 extern int val_print_string (CORE_ADDR addr
, int len
, int width
,
555 struct ui_file
*stream
,
556 const struct value_print_options
*options
);
558 extern void print_variable_value (struct symbol
*var
,
559 struct frame_info
*frame
,
560 struct ui_file
*stream
);
562 extern int check_field (struct type
*, const char *);
564 extern void typedef_print (struct type
*type
, struct symbol
*news
,
565 struct ui_file
*stream
);
567 extern char *internalvar_name (struct internalvar
*var
);
569 extern void preserve_values (struct objfile
*);
573 extern struct value
*value_copy (struct value
*);
577 extern struct value
*varying_to_slice (struct value
*);
579 extern struct value
*value_slice (struct value
*, int, int);
581 extern struct value
*value_literal_complex (struct value
*, struct value
*,
584 extern struct value
*find_function_in_inferior (const char *,
587 extern struct value
*value_allocate_space_in_inferior (int);
589 extern struct value
*value_of_local (const char *name
, int complain
);
591 extern struct value
* value_subscripted_rvalue (struct value
*array
, struct value
*idx
, int lowerbound
);
592 #endif /* !defined (VALUE_H) */