1 /* Definitions for values of C expressions, for GDB.
2 Copyright 1986, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995,
3 1996, 1997, 1998, 1999, 2000, 2001
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)
29 * The structure which defines the type of a value. It should never
30 * be possible for a program lval value to survive over a call to the inferior
31 * (ie to be put into the history list or an internal variable).
36 /* Type of value; either not an lval, or one of the various
37 different possible kinds of lval. */
39 /* Is it modifiable? Only relevant if lval != not_lval. */
41 /* Location of value (if lval). */
44 /* If lval == lval_memory, this is the address in the inferior.
45 If lval == lval_register, this is the byte offset into the
46 registers structure. */
48 /* Pointer to internal variable. */
49 struct internalvar
*internalvar
;
50 /* Number of register. Only used with
51 lval_reg_frame_relative. */
55 /* Describes offset of a value within lval of a structure in bytes.
56 If lval == lval_memory, this is an offset to the address.
57 If lval == lval_register, this is a further offset from
58 location.address within the registers structure.
59 Note also the member embedded_offset below. */
61 /* Only used for bitfields; number of bits contained in them. */
63 /* Only used for bitfields; position of start of field.
64 For BITS_BIG_ENDIAN=0 targets, it is the position of the LSB.
65 For BITS_BIG_ENDIAN=1 targets, it is the position of the MSB. */
67 /* Frame value is relative to. In practice, this address is only
68 used if the value is stored in several registers in other than
69 the current frame, and these registers have not all been saved
70 at the same place in memory. This will be described in the
71 lval enum above as "lval_reg_frame_relative". */
74 /* Type of the value. */
77 /* If a value represents a C++ object, then the `type' field gives
78 the object's compile-time type. If the object actually belongs
79 to some class derived from `type', perhaps with other base
80 classes and additional members, then `type' is just a subobject
81 of the real thing, and the full object is probably larger than
84 If `type' is a dynamic class (i.e. one with a vtable), then GDB
85 can actually determine the object's run-time type by looking at
86 the run-time type information in the vtable. When this
87 information is available, we may elect to read in the entire
88 object, for several reasons:
90 - When printing the value, the user would probably rather see
91 the full object, not just the limited portion apparent from
92 the compile-time type.
94 - If `type' has virtual base classes, then even printing
95 `type' alone may require reaching outside the `type'
96 portion of the object to wherever the virtual base class
99 When we store the entire object, `enclosing_type' is the
100 run-time type --- the complete object --- and `embedded_offset'
101 is the offset of `type' within that larger type, in bytes. The
102 VALUE_CONTENTS macro takes `embedded_offset' into account, so
103 most GDB code continues to see the `type' portion of the value,
104 just as the inferior would.
106 If `type' is a pointer to an object, then `enclosing_type' is a
107 pointer to the object's run-time type, and `pointed_to_offset'
108 is the offset in bytes from the full object to the pointed-to
109 object --- that is, the value `embedded_offset' would have if
110 we followed the pointer and fetched the complete object. (I
111 don't really see the point. Why not just determine the
112 run-time type when you indirect, and avoid the special case?
113 The contents don't matter until you indirect anyway.)
115 If we're not doing anything fancy, `enclosing_type' is equal to
116 `type', and `embedded_offset' is zero, so everything works
118 struct type
*enclosing_type
;
120 int pointed_to_offset
;
122 /* Values are stored in a chain, so that they can be deleted
123 easily over calls to the inferior. Values assigned to internal
124 variables or put into the value history are taken off this
128 /* ??? When is this used? */
136 /* Register number if the value is from a register. Is not kept
137 if you take a field of a structure that is stored in a
138 register. Shouldn't it be? */
140 /* If zero, contents of this value are in the contents field.
141 If nonzero, contents are in inferior memory at address
142 in the location.address field plus the offset field
143 (and the lval field should be lval_memory).
145 WARNING: This field is used by the code which handles
146 watchpoints (see breakpoint.c) to decide whether a particular
147 value can be watched by hardware watchpoints. If the lazy flag
148 is set for some member of a value chain, it is assumed that
149 this member of the chain doesn't need to be watched as part of
150 watching the value itself. This is how GDB avoids watching the
151 entire struct or array when the user wants to watch a single
152 struct member or array element. If you ever change the way
153 lazy flag is set and reset, be sure to consider this use as
156 /* If nonzero, this is the value of a variable which does not
157 actually exist in the program. */
159 /* The BFD section associated with this value. */
160 asection
*bfd_section
;
161 /* Actual contents of the value. For use of this value; setting
162 it uses the stuff above. Not valid if lazy is nonzero.
163 Target byte-order. We force it to be aligned properly for any
164 possible value. Note that a value therefore extends beyond
165 what is declared here. */
169 double force_double_align
;
170 LONGEST force_longlong_align
;
174 /* Do not add any new members here -- contents above will trash them */
177 typedef struct value
*value_ptr
;
179 #define VALUE_TYPE(val) (val)->type
180 #define VALUE_ENCLOSING_TYPE(val) (val)->enclosing_type
181 #define VALUE_LAZY(val) (val)->lazy
182 /* VALUE_CONTENTS and VALUE_CONTENTS_RAW both return the address of
183 the gdb buffer used to hold a copy of the contents of the lval.
184 VALUE_CONTENTS is used when the contents of the buffer are needed --
185 it uses value_fetch_lazy() to load the buffer from the process being
186 debugged if it hasn't already been loaded. VALUE_CONTENTS_RAW is
187 used when data is being stored into the buffer, or when it is
188 certain that the contents of the buffer are valid.
189 Note: The contents pointer is adjusted by the offset required to
190 get to the real subobject, if the value happens to represent
191 something embedded in a larger run-time object. */
193 #define VALUE_CONTENTS_RAW(val) ((char *) (val)->aligner.contents + (val)->embedded_offset)
194 #define VALUE_CONTENTS(val) ((void)(VALUE_LAZY(val) && value_fetch_lazy(val)),\
195 VALUE_CONTENTS_RAW(val))
197 /* The ALL variants of the above two macros do not adjust the returned
198 pointer by the embedded_offset value. */
200 #define VALUE_CONTENTS_ALL_RAW(val) ((char *) (val)->aligner.contents)
201 #define VALUE_CONTENTS_ALL(val) ((void) (VALUE_LAZY(val) && value_fetch_lazy(val)),\
202 VALUE_CONTENTS_ALL_RAW(val))
205 extern int value_fetch_lazy (value_ptr val
);
207 #define VALUE_LVAL(val) (val)->lval
208 #define VALUE_ADDRESS(val) (val)->location.address
209 #define VALUE_INTERNALVAR(val) (val)->location.internalvar
210 #define VALUE_FRAME_REGNUM(val) ((val)->location.regnum)
211 #define VALUE_FRAME(val) ((val)->frame_addr)
212 #define VALUE_OFFSET(val) (val)->offset
213 #define VALUE_BITSIZE(val) (val)->bitsize
214 #define VALUE_BITPOS(val) (val)->bitpos
215 #define VALUE_NEXT(val) (val)->next
216 #define VALUE_REGNO(val) (val)->regno
217 #define VALUE_OPTIMIZED_OUT(val) ((val)->optimized_out)
218 #define VALUE_EMBEDDED_OFFSET(val) ((val)->embedded_offset)
219 #define VALUE_POINTED_TO_OFFSET(val) ((val)->pointed_to_offset)
220 #define VALUE_BFD_SECTION(val) ((val)->bfd_section)
222 /* Convert a REF to the object referenced. */
224 #define COERCE_REF(arg) \
225 do { struct type *value_type_arg_tmp = check_typedef (VALUE_TYPE (arg));\
226 if (TYPE_CODE (value_type_arg_tmp) == TYPE_CODE_REF) \
227 arg = value_at_lazy (TYPE_TARGET_TYPE (value_type_arg_tmp), \
228 unpack_pointer (VALUE_TYPE (arg), \
229 VALUE_CONTENTS (arg)), \
230 VALUE_BFD_SECTION (arg)); \
233 /* If ARG is an array, convert it to a pointer.
234 If ARG is an enum, convert it to an integer.
235 If ARG is a function, convert it to a function pointer.
237 References are dereferenced. */
239 #define COERCE_ARRAY(arg) \
240 do { COERCE_REF(arg); \
241 if (current_language->c_style_arrays \
242 && TYPE_CODE (VALUE_TYPE (arg)) == TYPE_CODE_ARRAY) \
243 arg = value_coerce_array (arg); \
244 if (TYPE_CODE (VALUE_TYPE (arg)) == TYPE_CODE_FUNC) \
245 arg = value_coerce_function (arg); \
248 #define COERCE_NUMBER(arg) \
249 do { COERCE_ARRAY(arg); COERCE_ENUM(arg); } while (0)
251 #define COERCE_VARYING_ARRAY(arg, real_arg_type) \
252 { if (chill_varying_type (real_arg_type)) \
253 arg = varying_to_slice (arg), real_arg_type = VALUE_TYPE (arg); }
255 /* If ARG is an enum, convert it to an integer. */
257 #define COERCE_ENUM(arg) { \
258 if (TYPE_CODE (check_typedef (VALUE_TYPE (arg))) == TYPE_CODE_ENUM) \
259 arg = value_cast (builtin_type_unsigned_int, arg); \
262 /* Internal variables (variables for convenience of use of debugger)
263 are recorded as a chain of these structures. */
267 struct internalvar
*next
;
272 /* Pointer to member function. Depends on compiler implementation. */
274 #define METHOD_PTR_IS_VIRTUAL(ADDR) ((ADDR) & 0x80000000)
275 #define METHOD_PTR_FROM_VOFFSET(OFFSET) (0x80000000 + (OFFSET))
276 #define METHOD_PTR_TO_VOFFSET(ADDR) (~0x80000000 & (ADDR))
280 #include "gdbtypes.h"
281 #include "expression.h"
286 extern void print_address_demangle (CORE_ADDR
, struct ui_file
*, int);
288 extern LONGEST
value_as_long (value_ptr val
);
290 extern DOUBLEST
value_as_double (value_ptr val
);
292 extern CORE_ADDR
value_as_pointer (value_ptr val
);
294 extern LONGEST
unpack_long (struct type
*type
, char *valaddr
);
296 extern DOUBLEST
unpack_double (struct type
*type
, char *valaddr
, int *invp
);
298 extern CORE_ADDR
unpack_pointer (struct type
*type
, char *valaddr
);
300 extern LONGEST
unpack_field_as_long (struct type
*type
, char *valaddr
,
303 extern value_ptr
value_from_longest (struct type
*type
, LONGEST num
);
305 extern value_ptr
value_from_pointer (struct type
*type
, CORE_ADDR addr
);
307 extern value_ptr
value_from_double (struct type
*type
, DOUBLEST num
);
309 extern value_ptr
value_from_string (char *string
);
311 extern value_ptr
value_at (struct type
*type
, CORE_ADDR addr
,
314 extern value_ptr
value_at_lazy (struct type
*type
, CORE_ADDR addr
,
317 extern value_ptr
value_from_register (struct type
*type
, int regnum
,
318 struct frame_info
*frame
);
320 extern value_ptr
value_of_variable (struct symbol
*var
, struct block
*b
);
322 extern value_ptr
value_of_register (int regnum
);
324 extern int symbol_read_needs_frame (struct symbol
*);
326 extern value_ptr
read_var_value (struct symbol
*var
,
327 struct frame_info
*frame
);
329 extern value_ptr
locate_var_value (struct symbol
*var
,
330 struct frame_info
*frame
);
332 extern value_ptr
allocate_value (struct type
*type
);
334 extern value_ptr
allocate_repeat_value (struct type
*type
, int count
);
336 extern value_ptr
value_change_enclosing_type (value_ptr val
, struct type
*new_type
);
338 extern value_ptr
value_mark (void);
340 extern void value_free_to_mark (value_ptr mark
);
342 extern value_ptr
value_string (char *ptr
, int len
);
343 extern value_ptr
value_bitstring (char *ptr
, int len
);
345 extern value_ptr
value_array (int lowbound
, int highbound
,
346 value_ptr
* elemvec
);
348 extern value_ptr
value_concat (value_ptr arg1
, value_ptr arg2
);
350 extern value_ptr
value_binop (value_ptr arg1
, value_ptr arg2
,
353 extern value_ptr
value_add (value_ptr arg1
, value_ptr arg2
);
355 extern value_ptr
value_sub (value_ptr arg1
, value_ptr arg2
);
357 extern value_ptr
value_coerce_array (value_ptr arg1
);
359 extern value_ptr
value_coerce_function (value_ptr arg1
);
361 extern value_ptr
value_ind (value_ptr arg1
);
363 extern value_ptr
value_addr (value_ptr arg1
);
365 extern value_ptr
value_assign (value_ptr toval
, value_ptr fromval
);
367 extern value_ptr
value_neg (value_ptr arg1
);
369 extern value_ptr
value_complement (value_ptr arg1
);
371 extern value_ptr
value_struct_elt (value_ptr
* argp
, value_ptr
* args
,
373 int *static_memfuncp
, char *err
);
375 extern value_ptr
value_struct_elt_for_reference (struct type
*domain
,
377 struct type
*curtype
,
379 struct type
*intype
);
381 extern value_ptr
value_static_field (struct type
*type
, int fieldno
);
383 extern struct fn_field
*value_find_oload_method_list (value_ptr
*, char *,
385 struct type
**, int *);
387 extern int find_overload_match (struct type
**arg_types
, int nargs
,
388 char *name
, int method
, int lax
,
389 value_ptr obj
, struct symbol
*fsym
,
390 value_ptr
* valp
, struct symbol
**symp
,
393 extern value_ptr
value_field (value_ptr arg1
, int fieldno
);
395 extern value_ptr
value_primitive_field (value_ptr arg1
, int offset
,
396 int fieldno
, struct type
*arg_type
);
399 extern struct type
*value_rtti_target_type (value_ptr
, int *, int *, int *);
401 extern value_ptr
value_full_object (value_ptr
, struct type
*, int, int, int);
403 extern value_ptr
value_cast (struct type
*type
, value_ptr arg2
);
405 extern value_ptr
value_zero (struct type
*type
, enum lval_type lv
);
407 extern value_ptr
value_repeat (value_ptr arg1
, int count
);
409 extern value_ptr
value_subscript (value_ptr array
, value_ptr idx
);
411 extern value_ptr
value_from_vtable_info (value_ptr arg
, struct type
*type
);
413 extern value_ptr
value_being_returned (struct type
*valtype
,
414 char *retbuf
, int struct_return
);
416 extern value_ptr
value_in (value_ptr element
, value_ptr set
);
418 extern int value_bit_index (struct type
*type
, char *addr
, int index
);
420 extern int using_struct_return (value_ptr function
, CORE_ADDR funcaddr
,
421 struct type
*value_type
, int gcc_p
);
423 extern void set_return_value (value_ptr val
);
425 extern value_ptr
evaluate_expression (struct expression
*exp
);
427 extern value_ptr
evaluate_type (struct expression
*exp
);
429 extern value_ptr
evaluate_subexp_with_coercion (struct expression
*,
432 extern value_ptr
parse_and_eval (char *exp
);
434 extern value_ptr
parse_to_comma_and_eval (char **expp
);
436 extern struct type
*parse_and_eval_type (char *p
, int length
);
438 extern CORE_ADDR
parse_and_eval_address (char *exp
);
440 extern CORE_ADDR
parse_and_eval_address_1 (char **expptr
);
442 extern LONGEST
parse_and_eval_long (char *exp
);
444 extern value_ptr
access_value_history (int num
);
446 extern value_ptr
value_of_internalvar (struct internalvar
*var
);
448 extern void set_internalvar (struct internalvar
*var
, value_ptr val
);
450 extern void set_internalvar_component (struct internalvar
*var
,
452 int bitpos
, int bitsize
,
455 extern struct internalvar
*lookup_internalvar (char *name
);
457 extern int value_equal (value_ptr arg1
, value_ptr arg2
);
459 extern int value_less (value_ptr arg1
, value_ptr arg2
);
461 extern int value_logical_not (value_ptr arg1
);
465 extern value_ptr
value_of_this (int complain
);
467 extern value_ptr
value_x_binop (value_ptr arg1
, value_ptr arg2
,
469 enum exp_opcode otherop
, enum noside noside
);
471 extern value_ptr
value_x_unop (value_ptr arg1
, enum exp_opcode op
,
474 extern value_ptr
value_fn_field (value_ptr
* arg1p
, struct fn_field
*f
,
475 int j
, struct type
*type
, int offset
);
477 extern int binop_user_defined_p (enum exp_opcode op
,
478 value_ptr arg1
, value_ptr arg2
);
480 extern int unop_user_defined_p (enum exp_opcode op
, value_ptr 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 (value_ptr val
);
490 extern int record_latest_value (value_ptr val
);
493 modify_field (char *addr
, LONGEST fieldval
, int bitpos
, int bitsize
);
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
,
499 char *valaddr
, value_ptr
* 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 (value_ptr val
, struct ui_file
*stream
, int format
,
508 enum val_prettyprint pretty
);
510 extern void value_print_array_elements (value_ptr val
,
511 struct ui_file
*stream
,
513 enum val_prettyprint pretty
);
515 extern value_ptr
value_release_to_mark (value_ptr mark
);
517 extern int val_print (struct type
* type
, char *valaddr
,
518 int embedded_offset
, CORE_ADDR address
,
519 struct ui_file
* stream
, int format
,
520 int deref_ref
, int recurse
,
521 enum val_prettyprint pretty
);
523 extern int val_print_string (CORE_ADDR addr
, int len
, int width
, struct ui_file
*stream
);
525 extern void print_variable_value (struct symbol
* var
,
526 struct frame_info
* frame
,
527 struct ui_file
*stream
);
529 extern int check_field (value_ptr
, const char *);
531 extern void typedef_print (struct type
* type
, struct symbol
* news
,
532 struct ui_file
* stream
);
534 extern char *internalvar_name (struct internalvar
*var
);
536 extern void clear_value_history (void);
538 extern void clear_internalvars (void);
542 extern value_ptr
value_copy (value_ptr
);
544 extern int baseclass_offset (struct type
*, int, char *, CORE_ADDR
);
548 extern value_ptr
varying_to_slice (value_ptr
);
550 extern value_ptr
value_slice (value_ptr
, int, int);
552 extern value_ptr
call_function_by_hand (value_ptr
, int, value_ptr
*);
554 extern int default_coerce_float_to_double (struct type
*, struct type
*);
556 extern int standard_coerce_float_to_double (struct type
*, struct type
*);
558 extern value_ptr
value_literal_complex (value_ptr
, value_ptr
, struct type
*);
560 extern void find_rt_vbase_offset (struct type
*, struct type
*, char *, int,
563 extern value_ptr
find_function_in_inferior (char *);
565 extern value_ptr
value_allocate_space_in_inferior (int);
567 extern CORE_ADDR
default_push_arguments (int nargs
, value_ptr
* args
,
570 CORE_ADDR struct_addr
);
572 #endif /* !defined (VALUE_H) */