1 /* Definitions for values of C expressions, for GDB.
2 Copyright 1986, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994,
3 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003
4 Free Software Foundation, Inc.
6 This file is part of GDB.
8 This program is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 2 of the License, or
11 (at your option) any later version.
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with this program; if not, write to the Free Software
20 Foundation, Inc., 59 Temple Place - Suite 330,
21 Boston, MA 02111-1307, USA. */
23 #if !defined (VALUE_H)
31 * The structure which defines the type of a value. It should never
32 * be possible for a program lval value to survive over a call to the inferior
33 * (ie to be put into the history list or an internal variable).
38 /* Type of value; either not an lval, or one of the various
39 different possible kinds of lval. */
41 /* Is it modifiable? Only relevant if lval != not_lval. */
43 /* Location of value (if lval). */
46 /* If lval == lval_memory, this is the address in the inferior.
47 If lval == lval_register, this is the byte offset into the
48 registers structure. */
50 /* Pointer to internal variable. */
51 struct internalvar
*internalvar
;
52 /* Number of register. Only used with
53 lval_reg_frame_relative. */
57 /* Describes offset of a value within lval of a structure in bytes.
58 If lval == lval_memory, this is an offset to the address.
59 If lval == lval_register, this is a further offset from
60 location.address within the registers structure.
61 Note also the member embedded_offset below. */
63 /* Only used for bitfields; number of bits contained in them. */
65 /* Only used for bitfields; position of start of field.
66 For BITS_BIG_ENDIAN=0 targets, it is the position of the LSB.
67 For BITS_BIG_ENDIAN=1 targets, it is the position of the MSB. */
69 /* Frame value is relative to. In practice, this address is only
70 used if the value is stored in several registers in other than
71 the current frame, and these registers have not all been saved
72 at the same place in memory. This will be described in the
73 lval enum above as "lval_reg_frame_relative". */
76 /* Type of the value. */
79 /* If a value represents a C++ object, then the `type' field gives
80 the object's compile-time type. If the object actually belongs
81 to some class derived from `type', perhaps with other base
82 classes and additional members, then `type' is just a subobject
83 of the real thing, and the full object is probably larger than
86 If `type' is a dynamic class (i.e. one with a vtable), then GDB
87 can actually determine the object's run-time type by looking at
88 the run-time type information in the vtable. When this
89 information is available, we may elect to read in the entire
90 object, for several reasons:
92 - When printing the value, the user would probably rather see
93 the full object, not just the limited portion apparent from
94 the compile-time type.
96 - If `type' has virtual base classes, then even printing
97 `type' alone may require reaching outside the `type'
98 portion of the object to wherever the virtual base class
101 When we store the entire object, `enclosing_type' is the
102 run-time type --- the complete object --- and `embedded_offset'
103 is the offset of `type' within that larger type, in bytes. The
104 VALUE_CONTENTS macro takes `embedded_offset' into account, so
105 most GDB code continues to see the `type' portion of the value,
106 just as the inferior would.
108 If `type' is a pointer to an object, then `enclosing_type' is a
109 pointer to the object's run-time type, and `pointed_to_offset'
110 is the offset in bytes from the full object to the pointed-to
111 object --- that is, the value `embedded_offset' would have if
112 we followed the pointer and fetched the complete object. (I
113 don't really see the point. Why not just determine the
114 run-time type when you indirect, and avoid the special case?
115 The contents don't matter until you indirect anyway.)
117 If we're not doing anything fancy, `enclosing_type' is equal to
118 `type', and `embedded_offset' is zero, so everything works
120 struct type
*enclosing_type
;
122 int pointed_to_offset
;
124 /* Values are stored in a chain, so that they can be deleted
125 easily over calls to the inferior. Values assigned to internal
126 variables or put into the value history are taken off this
130 /* Register number if the value is from a register. Is not kept
131 if you take a field of a structure that is stored in a
132 register. Shouldn't it be? */
134 /* If zero, contents of this value are in the contents field.
135 If nonzero, contents are in inferior memory at address
136 in the location.address field plus the offset field
137 (and the lval field should be lval_memory).
139 WARNING: This field is used by the code which handles
140 watchpoints (see breakpoint.c) to decide whether a particular
141 value can be watched by hardware watchpoints. If the lazy flag
142 is set for some member of a value chain, it is assumed that
143 this member of the chain doesn't need to be watched as part of
144 watching the value itself. This is how GDB avoids watching the
145 entire struct or array when the user wants to watch a single
146 struct member or array element. If you ever change the way
147 lazy flag is set and reset, be sure to consider this use as
150 /* If nonzero, this is the value of a variable which does not
151 actually exist in the program. */
153 /* The BFD section associated with this value. */
154 asection
*bfd_section
;
155 /* Actual contents of the value. For use of this value; setting
156 it uses the stuff above. Not valid if lazy is nonzero.
157 Target byte-order. We force it to be aligned properly for any
158 possible value. Note that a value therefore extends beyond
159 what is declared here. */
163 DOUBLEST force_doublest_align
;
164 LONGEST force_longest_align
;
165 CORE_ADDR force_core_addr_align
;
166 void *force_pointer_align
;
169 /* Do not add any new members here -- contents above will trash them */
172 #define VALUE_TYPE(val) (val)->type
173 #define VALUE_ENCLOSING_TYPE(val) (val)->enclosing_type
174 #define VALUE_LAZY(val) (val)->lazy
175 /* VALUE_CONTENTS and VALUE_CONTENTS_RAW both return the address of
176 the gdb buffer used to hold a copy of the contents of the lval.
177 VALUE_CONTENTS is used when the contents of the buffer are needed --
178 it uses value_fetch_lazy() to load the buffer from the process being
179 debugged if it hasn't already been loaded. VALUE_CONTENTS_RAW is
180 used when data is being stored into the buffer, or when it is
181 certain that the contents of the buffer are valid.
182 Note: The contents pointer is adjusted by the offset required to
183 get to the real subobject, if the value happens to represent
184 something embedded in a larger run-time object. */
186 #define VALUE_CONTENTS_RAW(val) ((char *) (val)->aligner.contents + (val)->embedded_offset)
187 #define VALUE_CONTENTS(val) ((void)(VALUE_LAZY(val) && value_fetch_lazy(val)),\
188 VALUE_CONTENTS_RAW(val))
190 /* The ALL variants of the above two macros do not adjust the returned
191 pointer by the embedded_offset value. */
193 #define VALUE_CONTENTS_ALL_RAW(val) ((char *) (val)->aligner.contents)
194 #define VALUE_CONTENTS_ALL(val) ((void) (VALUE_LAZY(val) && value_fetch_lazy(val)),\
195 VALUE_CONTENTS_ALL_RAW(val))
198 extern int value_fetch_lazy (struct value
*val
);
200 #define VALUE_LVAL(val) (val)->lval
201 #define VALUE_ADDRESS(val) (val)->location.address
202 #define VALUE_INTERNALVAR(val) (val)->location.internalvar
203 #define VALUE_FRAME_REGNUM(val) ((val)->location.regnum)
204 #define VALUE_FRAME(val) ((val)->frame_addr)
205 #define VALUE_OFFSET(val) (val)->offset
206 #define VALUE_BITSIZE(val) (val)->bitsize
207 #define VALUE_BITPOS(val) (val)->bitpos
208 #define VALUE_NEXT(val) (val)->next
209 #define VALUE_REGNO(val) (val)->regno
210 #define VALUE_OPTIMIZED_OUT(val) ((val)->optimized_out)
211 #define VALUE_EMBEDDED_OFFSET(val) ((val)->embedded_offset)
212 #define VALUE_POINTED_TO_OFFSET(val) ((val)->pointed_to_offset)
213 #define VALUE_BFD_SECTION(val) ((val)->bfd_section)
215 /* Convert a REF to the object referenced. */
217 #define COERCE_REF(arg) \
218 do { struct type *value_type_arg_tmp = check_typedef (VALUE_TYPE (arg));\
219 if (TYPE_CODE (value_type_arg_tmp) == TYPE_CODE_REF) \
220 arg = value_at_lazy (TYPE_TARGET_TYPE (value_type_arg_tmp), \
221 unpack_pointer (VALUE_TYPE (arg), \
222 VALUE_CONTENTS (arg)), \
223 VALUE_BFD_SECTION (arg)); \
226 /* If ARG is an array, convert it to a pointer.
227 If ARG is an enum, convert it to an integer.
228 If ARG is a function, convert it to a function pointer.
230 References are dereferenced. */
232 #define COERCE_ARRAY(arg) \
233 do { COERCE_REF(arg); \
234 if (current_language->c_style_arrays \
235 && TYPE_CODE (VALUE_TYPE (arg)) == TYPE_CODE_ARRAY) \
236 arg = value_coerce_array (arg); \
237 if (TYPE_CODE (VALUE_TYPE (arg)) == TYPE_CODE_FUNC) \
238 arg = value_coerce_function (arg); \
241 #define COERCE_NUMBER(arg) \
242 do { COERCE_ARRAY(arg); COERCE_ENUM(arg); } while (0)
244 /* NOTE: cagney/2002-12-17: This macro was handling a chill language
245 problem but that language has gone away. */
246 #define COERCE_VARYING_ARRAY(arg, real_arg_type)
248 /* If ARG is an enum, convert it to an integer. */
250 #define COERCE_ENUM(arg) { \
251 if (TYPE_CODE (check_typedef (VALUE_TYPE (arg))) == TYPE_CODE_ENUM) \
252 arg = value_cast (builtin_type_unsigned_int, arg); \
255 /* Internal variables (variables for convenience of use of debugger)
256 are recorded as a chain of these structures. */
260 struct internalvar
*next
;
265 /* Pointer to member function. Depends on compiler implementation. */
267 #define METHOD_PTR_IS_VIRTUAL(ADDR) ((ADDR) & 0x80000000)
268 #define METHOD_PTR_FROM_VOFFSET(OFFSET) (0x80000000 + (OFFSET))
269 #define METHOD_PTR_TO_VOFFSET(ADDR) (~0x80000000 & (ADDR))
273 #include "gdbtypes.h"
274 #include "expression.h"
279 extern void print_address_demangle (CORE_ADDR
, struct ui_file
*, int);
281 extern LONGEST
value_as_long (struct value
*val
);
283 extern DOUBLEST
value_as_double (struct value
*val
);
285 extern CORE_ADDR
value_as_address (struct value
*val
);
287 extern LONGEST
unpack_long (struct type
*type
, const char *valaddr
);
289 extern DOUBLEST
unpack_double (struct type
*type
, const char *valaddr
,
292 extern CORE_ADDR
unpack_pointer (struct type
*type
, const char *valaddr
);
294 extern LONGEST
unpack_field_as_long (struct type
*type
, const char *valaddr
,
297 extern struct value
*value_from_longest (struct type
*type
, LONGEST num
);
299 extern struct value
*value_from_pointer (struct type
*type
, CORE_ADDR addr
);
301 extern struct value
*value_from_double (struct type
*type
, DOUBLEST num
);
303 extern struct value
*value_from_string (char *string
);
305 extern struct value
*value_at (struct type
*type
, CORE_ADDR addr
,
308 extern struct value
*value_at_lazy (struct type
*type
, CORE_ADDR addr
,
311 extern struct value
*value_from_register (struct type
*type
, int regnum
,
312 struct frame_info
*frame
);
314 extern struct value
*value_of_variable (struct symbol
*var
, struct block
*b
);
316 extern struct value
*value_of_register (int regnum
,
317 struct frame_info
*frame
);
319 extern int symbol_read_needs_frame (struct symbol
*);
321 extern struct value
*read_var_value (struct symbol
*var
,
322 struct frame_info
*frame
);
324 extern struct value
*locate_var_value (struct symbol
*var
,
325 struct frame_info
*frame
);
327 extern struct value
*allocate_value (struct type
*type
);
329 extern struct value
*allocate_repeat_value (struct type
*type
, int count
);
331 extern struct value
*value_change_enclosing_type (struct value
*val
,
332 struct type
*new_type
);
334 extern struct value
*value_mark (void);
336 extern void value_free_to_mark (struct value
*mark
);
338 extern struct value
*value_string (char *ptr
, int len
);
339 extern struct value
*value_bitstring (char *ptr
, int len
);
341 extern struct value
*value_array (int lowbound
, int highbound
,
342 struct value
** elemvec
);
344 extern struct value
*value_concat (struct value
*arg1
, struct value
*arg2
);
346 extern struct value
*value_binop (struct value
*arg1
, struct value
*arg2
,
349 extern struct value
*value_add (struct value
*arg1
, struct value
*arg2
);
351 extern struct value
*value_sub (struct value
*arg1
, struct value
*arg2
);
353 extern struct value
*value_coerce_array (struct value
*arg1
);
355 extern struct value
*value_coerce_function (struct value
*arg1
);
357 extern struct value
*value_ind (struct value
*arg1
);
359 extern struct value
*value_addr (struct value
*arg1
);
361 extern struct value
*value_assign (struct value
*toval
, struct value
*fromval
);
363 extern struct value
*value_neg (struct value
*arg1
);
365 extern struct value
*value_complement (struct value
*arg1
);
367 extern struct value
*value_struct_elt (struct value
**argp
,
369 char *name
, int *static_memfuncp
,
372 extern struct value
*value_struct_elt_for_reference (struct type
*domain
,
374 struct type
*curtype
,
376 struct type
*intype
);
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 (struct type
*type
, struct value
*arg2
);
405 extern struct value
*value_zero (struct type
*type
, enum lval_type lv
);
407 extern struct value
*value_repeat (struct value
*arg1
, int count
);
409 extern struct value
*value_subscript (struct value
*array
, struct value
*idx
);
411 extern struct value
*value_being_returned (struct type
*valtype
,
412 struct regcache
*retbuf
,
415 extern struct value
*value_in (struct value
*element
, struct value
*set
);
417 extern int value_bit_index (struct type
*type
, char *addr
, int index
);
419 extern int using_struct_return (struct value
*function
, CORE_ADDR funcaddr
,
420 struct type
*value_type
, int gcc_p
);
422 extern void set_return_value (struct value
*val
);
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
*call_function_by_hand (struct value
*, int,
552 extern struct value
*value_literal_complex (struct value
*, struct value
*,
555 extern void find_rt_vbase_offset (struct type
*, struct type
*, char *, int,
558 extern struct value
*find_function_in_inferior (const char *);
560 extern struct value
*value_allocate_space_in_inferior (int);
562 extern CORE_ADDR
default_push_arguments (int nargs
, struct value
** args
,
563 CORE_ADDR sp
, int struct_return
,
564 CORE_ADDR struct_addr
);
566 extern struct value
*value_of_local (const char *name
, int complain
);
568 #endif /* !defined (VALUE_H) */