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
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
;
62 /* Number of register. Only used with lval_reg_frame_relative. */
66 /* Describes offset of a value within lval of a structure in bytes.
67 If lval == lval_memory, this is an offset to the address.
68 If lval == lval_register, this is a further offset from
69 location.address within the registers structure.
70 Note also the member embedded_offset below. */
73 /* Only used for bitfields; number of bits contained in them. */
76 /* Only used for bitfields; position of start of field.
77 For BITS_BIG_ENDIAN=0 targets, it is the position of the LSB.
78 For BITS_BIG_ENDIAN=1 targets, it is the position of the MSB. */
81 /* Frame value is relative to. In practice, this ID is only used if
82 the value is stored in several registers in other than the
83 current frame, and these registers have not all been saved at the
84 same place in memory. This will be described in the lval enum
85 above as "lval_reg_frame_relative". */
86 struct frame_id frame_id
;
88 /* Type of the value. */
91 /* If a value represents a C++ object, then the `type' field gives
92 the object's compile-time type. If the object actually belongs
93 to some class derived from `type', perhaps with other base
94 classes and additional members, then `type' is just a subobject
95 of the real thing, and the full object is probably larger than
98 If `type' is a dynamic class (i.e. one with a vtable), then GDB
99 can actually determine the object's run-time type by looking at
100 the run-time type information in the vtable. When this
101 information is available, we may elect to read in the entire
102 object, for several reasons:
104 - When printing the value, the user would probably rather see the
105 full object, not just the limited portion apparent from the
108 - If `type' has virtual base classes, then even printing `type'
109 alone may require reaching outside the `type' portion of the
110 object to wherever the virtual base class has been stored.
112 When we store the entire object, `enclosing_type' is the run-time
113 type -- the complete object -- and `embedded_offset' is the
114 offset of `type' within that larger type, in bytes. The
115 VALUE_CONTENTS macro takes `embedded_offset' into account, so
116 most GDB code continues to see the `type' portion of the value,
117 just as the inferior would.
119 If `type' is a pointer to an object, then `enclosing_type' is a
120 pointer to the object's run-time type, and `pointed_to_offset' is
121 the offset in bytes from the full object to the pointed-to object
122 -- that is, the value `embedded_offset' would have if we
123 followed the pointer and fetched the complete object. (I don't
124 really see the point. Why not just determine the run-time type
125 when you indirect, and avoid the special case? The contents
126 don't matter until you indirect anyway.)
128 If we're not doing anything fancy, `enclosing_type' is equal to
129 `type', and `embedded_offset' is zero, so everything works
131 struct type
*enclosing_type
;
133 int pointed_to_offset
;
135 /* Values are stored in a chain, so that they can be deleted
136 easily over calls to the inferior. Values assigned to internal
137 variables or put into the value history are taken off this
141 /* Register number if the value is from a register. */
144 /* If zero, contents of this value are in the contents field. If
145 nonzero, contents are in inferior memory at address in the
146 location.address field plus the offset field (and the lval
147 field should be lval_memory).
149 WARNING: This field is used by the code which handles
150 watchpoints (see breakpoint.c) to decide whether a particular
151 value can be watched by hardware watchpoints. If the lazy flag
152 is set for some member of a value chain, it is assumed that
153 this member of the chain doesn't need to be watched as part of
154 watching the value itself. This is how GDB avoids watching the
155 entire struct or array when the user wants to watch a single
156 struct member or array element. If you ever change the way
157 lazy flag is set and reset, be sure to consider this use as
161 /* If nonzero, this is the value of a variable which does not
162 actually exist in the program. */
165 /* The BFD section associated with this value. */
166 asection
*bfd_section
;
168 /* Actual contents of the value. For use of this value; setting
169 it uses the stuff above. Not valid if lazy is nonzero.
170 Target byte-order. We force it to be aligned properly for any
171 possible value. Note that a value therefore extends beyond
172 what is declared here. */
176 DOUBLEST force_doublest_align
;
177 LONGEST force_longest_align
;
178 CORE_ADDR force_core_addr_align
;
179 void *force_pointer_align
;
181 /* Do not add any new members here -- contents above will trash them. */
184 #define VALUE_TYPE(val) (val)->type
185 #define VALUE_ENCLOSING_TYPE(val) (val)->enclosing_type
186 #define VALUE_LAZY(val) (val)->lazy
188 /* VALUE_CONTENTS and VALUE_CONTENTS_RAW both return the address of
189 the gdb buffer used to hold a copy of the contents of the lval.
190 VALUE_CONTENTS is used when the contents of the buffer are needed
191 -- it uses value_fetch_lazy() to load the buffer from the process
192 being debugged if it hasn't already been loaded.
193 VALUE_CONTENTS_RAW is used when data is being stored into the
194 buffer, or when it is certain that the contents of the buffer are
197 Note: The contents pointer is adjusted by the offset required to
198 get to the real subobject, if the value happens to represent
199 something embedded in a larger run-time object. */
201 #define VALUE_CONTENTS_RAW(val) \
202 ((char *) (val)->aligner.contents + (val)->embedded_offset)
203 #define VALUE_CONTENTS(val) \
204 ((void)(VALUE_LAZY(val) && value_fetch_lazy(val)), VALUE_CONTENTS_RAW(val))
206 /* The ALL variants of the above two macros do not adjust the returned
207 pointer by the embedded_offset value. */
209 #define VALUE_CONTENTS_ALL_RAW(val) ((char *) (val)->aligner.contents)
210 #define VALUE_CONTENTS_ALL(val) \
211 ((void) (VALUE_LAZY(val) && value_fetch_lazy(val)), \
212 VALUE_CONTENTS_ALL_RAW(val))
214 extern int value_fetch_lazy (struct value
*val
);
216 #define VALUE_LVAL(val) (val)->lval
217 #define VALUE_ADDRESS(val) (val)->location.address
218 #define VALUE_INTERNALVAR(val) (val)->location.internalvar
219 #define VALUE_FRAME_REGNUM(val) ((val)->location.regnum)
220 #define VALUE_FRAME_ID(val) ((val)->frame_id)
221 #define VALUE_OFFSET(val) (val)->offset
222 #define VALUE_BITSIZE(val) (val)->bitsize
223 #define VALUE_BITPOS(val) (val)->bitpos
224 #define VALUE_NEXT(val) (val)->next
225 #define VALUE_REGNO(val) (val)->regno
226 #define VALUE_OPTIMIZED_OUT(val) ((val)->optimized_out)
227 #define VALUE_EMBEDDED_OFFSET(val) ((val)->embedded_offset)
228 #define VALUE_POINTED_TO_OFFSET(val) ((val)->pointed_to_offset)
229 #define VALUE_BFD_SECTION(val) ((val)->bfd_section)
231 /* Convert a REF to the object referenced. */
233 #define COERCE_REF(arg) \
235 struct type *value_type_arg_tmp = check_typedef (VALUE_TYPE (arg)); \
236 if (TYPE_CODE (value_type_arg_tmp) == TYPE_CODE_REF) \
237 arg = value_at_lazy (TYPE_TARGET_TYPE (value_type_arg_tmp), \
238 unpack_pointer (VALUE_TYPE (arg), \
239 VALUE_CONTENTS (arg)), \
240 VALUE_BFD_SECTION (arg)); \
243 /* If ARG is an array, convert it to a pointer.
244 If ARG is an enum, convert it to an integer.
245 If ARG is a function, convert it to a function pointer.
247 References are dereferenced. */
249 #define COERCE_ARRAY(arg) \
252 if (current_language->c_style_arrays \
253 && TYPE_CODE (VALUE_TYPE (arg)) == TYPE_CODE_ARRAY) \
254 arg = value_coerce_array (arg); \
255 if (TYPE_CODE (VALUE_TYPE (arg)) == TYPE_CODE_FUNC) \
256 arg = value_coerce_function (arg); \
259 #define COERCE_NUMBER(arg) \
260 do { COERCE_ARRAY(arg); COERCE_ENUM(arg); } while (0)
262 /* If ARG is an enum, convert it to an integer. */
264 #define COERCE_ENUM(arg) \
266 if (TYPE_CODE (check_typedef (VALUE_TYPE (arg))) == TYPE_CODE_ENUM) \
267 arg = value_cast (builtin_type_unsigned_int, arg); \
270 /* Internal variables (variables for convenience of use of debugger)
271 are recorded as a chain of these structures. */
275 struct internalvar
*next
;
280 /* Pointer to member function. Depends on compiler implementation. */
282 #define METHOD_PTR_IS_VIRTUAL(ADDR) ((ADDR) & 0x80000000)
283 #define METHOD_PTR_FROM_VOFFSET(OFFSET) (0x80000000 + (OFFSET))
284 #define METHOD_PTR_TO_VOFFSET(ADDR) (~0x80000000 & (ADDR))
288 #include "gdbtypes.h"
289 #include "expression.h"
294 extern void print_address_demangle (CORE_ADDR
, struct ui_file
*, int);
296 extern LONGEST
value_as_long (struct value
*val
);
297 extern DOUBLEST
value_as_double (struct value
*val
);
298 extern CORE_ADDR
value_as_address (struct value
*val
);
300 extern LONGEST
unpack_long (struct type
*type
, const char *valaddr
);
301 extern DOUBLEST
unpack_double (struct type
*type
, const char *valaddr
,
303 extern CORE_ADDR
unpack_pointer (struct type
*type
, const char *valaddr
);
304 extern LONGEST
unpack_field_as_long (struct type
*type
, const char *valaddr
,
307 extern struct value
*value_from_longest (struct type
*type
, LONGEST num
);
308 extern struct value
*value_from_pointer (struct type
*type
, CORE_ADDR addr
);
309 extern struct value
*value_from_double (struct type
*type
, DOUBLEST num
);
310 extern struct value
*value_from_string (char *string
);
312 extern struct value
*value_at (struct type
*type
, CORE_ADDR addr
,
314 extern struct value
*value_at_lazy (struct type
*type
, CORE_ADDR addr
,
317 extern struct value
*value_from_register (struct type
*type
, int regnum
,
318 struct frame_info
*frame
);
320 extern struct value
*value_of_variable (struct symbol
*var
, struct block
*b
);
322 extern struct value
*value_of_register (int regnum
,
323 struct frame_info
*frame
);
325 extern int symbol_read_needs_frame (struct symbol
*);
327 extern struct value
*read_var_value (struct symbol
*var
,
328 struct frame_info
*frame
);
330 extern struct value
*locate_var_value (struct symbol
*var
,
331 struct frame_info
*frame
);
333 extern struct value
*allocate_value (struct type
*type
);
335 extern struct value
*allocate_repeat_value (struct type
*type
, int count
);
337 extern struct value
*value_change_enclosing_type (struct value
*val
,
338 struct type
*new_type
);
340 extern struct value
*value_mark (void);
342 extern void value_free_to_mark (struct value
*mark
);
344 extern struct value
*value_string (char *ptr
, int len
);
345 extern struct value
*value_bitstring (char *ptr
, int len
);
347 extern struct value
*value_array (int lowbound
, int highbound
,
348 struct value
** elemvec
);
350 extern struct value
*value_concat (struct value
*arg1
, struct value
*arg2
);
352 extern struct value
*value_binop (struct value
*arg1
, struct value
*arg2
,
355 extern struct value
*value_add (struct value
*arg1
, struct value
*arg2
);
357 extern struct value
*value_sub (struct value
*arg1
, struct value
*arg2
);
359 extern struct value
*value_coerce_array (struct value
*arg1
);
361 extern struct value
*value_coerce_function (struct value
*arg1
);
363 extern struct value
*value_ind (struct value
*arg1
);
365 extern struct value
*value_addr (struct value
*arg1
);
367 extern struct value
*value_assign (struct value
*toval
, struct value
*fromval
);
369 extern struct value
*value_neg (struct value
*arg1
);
371 extern struct value
*value_complement (struct value
*arg1
);
373 extern struct value
*value_struct_elt (struct value
**argp
,
375 char *name
, int *static_memfuncp
,
378 extern struct value
*value_aggregate_elt (struct type
*curtype
,
382 extern struct value
*value_static_field (struct type
*type
, int fieldno
);
384 extern struct fn_field
*value_find_oload_method_list (struct value
**, char *,
386 struct type
**, int *);
388 extern int find_overload_match (struct type
**arg_types
, int nargs
,
389 char *name
, int method
, int lax
,
390 struct value
**objp
, struct symbol
*fsym
,
391 struct value
**valp
, struct symbol
**symp
,
394 extern struct value
*value_field (struct value
*arg1
, int fieldno
);
396 extern struct value
*value_primitive_field (struct value
*arg1
, int offset
,
398 struct type
*arg_type
);
401 extern struct type
*value_rtti_target_type (struct value
*, int *, int *,
404 extern struct value
*value_full_object (struct value
*, struct type
*, int,
407 extern struct value
*value_cast (struct type
*type
, struct value
*arg2
);
409 extern struct value
*value_zero (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
*register_value_being_returned (struct type
*valtype
,
416 struct regcache
*retbuf
);
418 extern struct value
*value_in (struct value
*element
, struct value
*set
);
420 extern int value_bit_index (struct type
*type
, char *addr
, int index
);
422 extern int using_struct_return (struct type
*value_type
, int gcc_p
);
424 extern struct value
*evaluate_expression (struct expression
*exp
);
426 extern struct value
*evaluate_type (struct expression
*exp
);
428 extern struct value
*evaluate_subexp_with_coercion (struct expression
*,
431 extern struct value
*parse_and_eval (char *exp
);
433 extern struct value
*parse_to_comma_and_eval (char **expp
);
435 extern struct type
*parse_and_eval_type (char *p
, int length
);
437 extern CORE_ADDR
parse_and_eval_address (char *exp
);
439 extern CORE_ADDR
parse_and_eval_address_1 (char **expptr
);
441 extern LONGEST
parse_and_eval_long (char *exp
);
443 extern struct value
*access_value_history (int num
);
445 extern struct value
*value_of_internalvar (struct internalvar
*var
);
447 extern void set_internalvar (struct internalvar
*var
, struct value
*val
);
449 extern void set_internalvar_component (struct internalvar
*var
,
451 int bitpos
, int bitsize
,
452 struct value
*newvalue
);
454 extern struct internalvar
*lookup_internalvar (char *name
);
456 extern int value_equal (struct value
*arg1
, struct value
*arg2
);
458 extern int value_less (struct value
*arg1
, struct value
*arg2
);
460 extern int value_logical_not (struct value
*arg1
);
464 extern struct value
*value_of_this (int complain
);
466 extern struct value
*value_x_binop (struct value
*arg1
, struct value
*arg2
,
468 enum exp_opcode otherop
,
471 extern struct value
*value_x_unop (struct value
*arg1
, enum exp_opcode op
,
474 extern struct value
*value_fn_field (struct value
** arg1p
, struct fn_field
*f
,
475 int j
, struct type
*type
, int offset
);
477 extern int binop_user_defined_p (enum exp_opcode op
, struct value
*arg1
,
480 extern int unop_user_defined_p (enum exp_opcode op
, struct value
*arg1
);
482 extern int destructor_name_p (const char *name
, const struct type
*type
);
484 #define value_free(val) xfree (val)
486 extern void free_all_values (void);
488 extern void release_value (struct value
*val
);
490 extern int record_latest_value (struct value
*val
);
492 extern void modify_field (char *addr
, LONGEST fieldval
, int bitpos
,
495 extern void type_print (struct type
* type
, char *varstring
,
496 struct ui_file
* stream
, int show
);
498 extern char *baseclass_addr (struct type
*type
, int index
, char *valaddr
,
499 struct value
**valuep
, int *errp
);
501 extern void print_longest (struct ui_file
* stream
, int format
,
502 int use_local
, LONGEST val
);
504 extern void print_floating (char *valaddr
, struct type
* type
,
505 struct ui_file
* stream
);
507 extern int value_print (struct value
*val
, struct ui_file
*stream
, int format
,
508 enum val_prettyprint pretty
);
510 extern void value_print_array_elements (struct value
*val
,
511 struct ui_file
*stream
, int format
,
512 enum val_prettyprint pretty
);
514 extern struct value
*value_release_to_mark (struct value
*mark
);
516 extern int val_print (struct type
* type
, char *valaddr
,
517 int embedded_offset
, CORE_ADDR address
,
518 struct ui_file
* stream
, int format
,
519 int deref_ref
, int recurse
,
520 enum val_prettyprint pretty
);
522 extern int val_print_string (CORE_ADDR addr
, int len
, int width
, struct ui_file
*stream
);
524 extern void print_variable_value (struct symbol
* var
,
525 struct frame_info
* frame
,
526 struct ui_file
*stream
);
528 extern int check_field (struct value
*, const char *);
530 extern void typedef_print (struct type
* type
, struct symbol
* news
,
531 struct ui_file
* stream
);
533 extern char *internalvar_name (struct internalvar
*var
);
535 extern void clear_value_history (void);
537 extern void clear_internalvars (void);
541 extern struct value
*value_copy (struct value
*);
545 extern struct value
*varying_to_slice (struct value
*);
547 extern struct value
*value_slice (struct value
*, int, int);
549 extern struct value
*value_literal_complex (struct value
*, struct value
*,
552 extern void find_rt_vbase_offset (struct type
*, struct type
*, char *, int,
555 extern struct value
*find_function_in_inferior (const char *);
557 extern struct value
*value_allocate_space_in_inferior (int);
559 extern struct value
*value_of_local (const char *name
, int complain
);
561 #endif /* !defined (VALUE_H) */