1 /* Low level packing and unpacking of values for GDB, the GNU Debugger.
3 Copyright (C) 1986, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995,
4 1996, 1997, 1998, 1999, 2000, 2002, 2003, 2004, 2005, 2006, 2007, 2008,
5 2009, 2010, 2011 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/>. */
23 #include "arch-utils.h"
24 #include "gdb_string.h"
35 #include "gdb_assert.h"
41 #include "cli/cli-decode.h"
42 #include "exceptions.h"
43 #include "python/python.h"
45 #include "tracepoint.h"
47 /* Prototypes for exported functions. */
49 void _initialize_values (void);
51 /* Definition of a user function. */
52 struct internal_function
54 /* The name of the function. It is a bit odd to have this in the
55 function itself -- the user might use a differently-named
56 convenience variable to hold the function. */
60 internal_function_fn handler
;
62 /* User data for the handler. */
66 /* Defines an [OFFSET, OFFSET + LENGTH) range. */
70 /* Lowest offset in the range. */
73 /* Length of the range. */
77 typedef struct range range_s
;
81 /* Returns true if the ranges defined by [offset1, offset1+len1) and
82 [offset2, offset2+len2) overlap. */
85 ranges_overlap (int offset1
, int len1
,
86 int offset2
, int len2
)
90 l
= max (offset1
, offset2
);
91 h
= min (offset1
+ len1
, offset2
+ len2
);
95 /* Returns true if the first argument is strictly less than the
96 second, useful for VEC_lower_bound. We keep ranges sorted by
97 offset and coalesce overlapping and contiguous ranges, so this just
98 compares the starting offset. */
101 range_lessthan (const range_s
*r1
, const range_s
*r2
)
103 return r1
->offset
< r2
->offset
;
106 /* Returns true if RANGES contains any range that overlaps [OFFSET,
110 ranges_contain (VEC(range_s
) *ranges
, int offset
, int length
)
115 what
.offset
= offset
;
116 what
.length
= length
;
118 /* We keep ranges sorted by offset and coalesce overlapping and
119 contiguous ranges, so to check if a range list contains a given
120 range, we can do a binary search for the position the given range
121 would be inserted if we only considered the starting OFFSET of
122 ranges. We call that position I. Since we also have LENGTH to
123 care for (this is a range afterall), we need to check if the
124 _previous_ range overlaps the I range. E.g.,
128 |---| |---| |------| ... |--|
133 In the case above, the binary search would return `I=1', meaning,
134 this OFFSET should be inserted at position 1, and the current
135 position 1 should be pushed further (and before 2). But, `0'
138 Then we need to check if the I range overlaps the I range itself.
143 |---| |---| |-------| ... |--|
149 i
= VEC_lower_bound (range_s
, ranges
, &what
, range_lessthan
);
153 struct range
*bef
= VEC_index (range_s
, ranges
, i
- 1);
155 if (ranges_overlap (bef
->offset
, bef
->length
, offset
, length
))
159 if (i
< VEC_length (range_s
, ranges
))
161 struct range
*r
= VEC_index (range_s
, ranges
, i
);
163 if (ranges_overlap (r
->offset
, r
->length
, offset
, length
))
170 static struct cmd_list_element
*functionlist
;
174 /* Type of value; either not an lval, or one of the various
175 different possible kinds of lval. */
178 /* Is it modifiable? Only relevant if lval != not_lval. */
181 /* Location of value (if lval). */
184 /* If lval == lval_memory, this is the address in the inferior.
185 If lval == lval_register, this is the byte offset into the
186 registers structure. */
189 /* Pointer to internal variable. */
190 struct internalvar
*internalvar
;
192 /* If lval == lval_computed, this is a set of function pointers
193 to use to access and describe the value, and a closure pointer
197 /* Functions to call. */
198 const struct lval_funcs
*funcs
;
200 /* Closure for those functions to use. */
205 /* Describes offset of a value within lval of a structure in bytes.
206 If lval == lval_memory, this is an offset to the address. If
207 lval == lval_register, this is a further offset from
208 location.address within the registers structure. Note also the
209 member embedded_offset below. */
212 /* Only used for bitfields; number of bits contained in them. */
215 /* Only used for bitfields; position of start of field. For
216 gdbarch_bits_big_endian=0 targets, it is the position of the LSB. For
217 gdbarch_bits_big_endian=1 targets, it is the position of the MSB. */
220 /* Only used for bitfields; the containing value. This allows a
221 single read from the target when displaying multiple
223 struct value
*parent
;
225 /* Frame register value is relative to. This will be described in
226 the lval enum above as "lval_register". */
227 struct frame_id frame_id
;
229 /* Type of the value. */
232 /* If a value represents a C++ object, then the `type' field gives
233 the object's compile-time type. If the object actually belongs
234 to some class derived from `type', perhaps with other base
235 classes and additional members, then `type' is just a subobject
236 of the real thing, and the full object is probably larger than
237 `type' would suggest.
239 If `type' is a dynamic class (i.e. one with a vtable), then GDB
240 can actually determine the object's run-time type by looking at
241 the run-time type information in the vtable. When this
242 information is available, we may elect to read in the entire
243 object, for several reasons:
245 - When printing the value, the user would probably rather see the
246 full object, not just the limited portion apparent from the
249 - If `type' has virtual base classes, then even printing `type'
250 alone may require reaching outside the `type' portion of the
251 object to wherever the virtual base class has been stored.
253 When we store the entire object, `enclosing_type' is the run-time
254 type -- the complete object -- and `embedded_offset' is the
255 offset of `type' within that larger type, in bytes. The
256 value_contents() macro takes `embedded_offset' into account, so
257 most GDB code continues to see the `type' portion of the value,
258 just as the inferior would.
260 If `type' is a pointer to an object, then `enclosing_type' is a
261 pointer to the object's run-time type, and `pointed_to_offset' is
262 the offset in bytes from the full object to the pointed-to object
263 -- that is, the value `embedded_offset' would have if we followed
264 the pointer and fetched the complete object. (I don't really see
265 the point. Why not just determine the run-time type when you
266 indirect, and avoid the special case? The contents don't matter
267 until you indirect anyway.)
269 If we're not doing anything fancy, `enclosing_type' is equal to
270 `type', and `embedded_offset' is zero, so everything works
272 struct type
*enclosing_type
;
274 int pointed_to_offset
;
276 /* Values are stored in a chain, so that they can be deleted easily
277 over calls to the inferior. Values assigned to internal
278 variables, put into the value history or exposed to Python are
279 taken off this list. */
282 /* Register number if the value is from a register. */
285 /* If zero, contents of this value are in the contents field. If
286 nonzero, contents are in inferior. If the lval field is lval_memory,
287 the contents are in inferior memory at location.address plus offset.
288 The lval field may also be lval_register.
290 WARNING: This field is used by the code which handles watchpoints
291 (see breakpoint.c) to decide whether a particular value can be
292 watched by hardware watchpoints. If the lazy flag is set for
293 some member of a value chain, it is assumed that this member of
294 the chain doesn't need to be watched as part of watching the
295 value itself. This is how GDB avoids watching the entire struct
296 or array when the user wants to watch a single struct member or
297 array element. If you ever change the way lazy flag is set and
298 reset, be sure to consider this use as well! */
301 /* If nonzero, this is the value of a variable which does not
302 actually exist in the program. */
305 /* If value is a variable, is it initialized or not. */
308 /* If value is from the stack. If this is set, read_stack will be
309 used instead of read_memory to enable extra caching. */
312 /* Actual contents of the value. Target byte-order. NULL or not
313 valid if lazy is nonzero. */
316 /* Unavailable ranges in CONTENTS. We mark unavailable ranges,
317 rather than available, since the common and default case is for a
318 value to be available. This is filled in at value read time. */
319 VEC(range_s
) *unavailable
;
321 /* The number of references to this value. When a value is created,
322 the value chain holds a reference, so REFERENCE_COUNT is 1. If
323 release_value is called, this value is removed from the chain but
324 the caller of release_value now has a reference to this value.
325 The caller must arrange for a call to value_free later. */
330 value_bytes_available (const struct value
*value
, int offset
, int length
)
332 gdb_assert (!value
->lazy
);
334 return !ranges_contain (value
->unavailable
, offset
, length
);
338 value_entirely_available (struct value
*value
)
340 /* We can only tell whether the whole value is available when we try
343 value_fetch_lazy (value
);
345 if (VEC_empty (range_s
, value
->unavailable
))
351 mark_value_bytes_unavailable (struct value
*value
, int offset
, int length
)
356 /* Insert the range sorted. If there's overlap or the new range
357 would be contiguous with an existing range, merge. */
359 newr
.offset
= offset
;
360 newr
.length
= length
;
362 /* Do a binary search for the position the given range would be
363 inserted if we only considered the starting OFFSET of ranges.
364 Call that position I. Since we also have LENGTH to care for
365 (this is a range afterall), we need to check if the _previous_
366 range overlaps the I range. E.g., calling R the new range:
368 #1 - overlaps with previous
372 |---| |---| |------| ... |--|
377 In the case #1 above, the binary search would return `I=1',
378 meaning, this OFFSET should be inserted at position 1, and the
379 current position 1 should be pushed further (and become 2). But,
380 note that `0' overlaps with R, so we want to merge them.
382 A similar consideration needs to be taken if the new range would
383 be contiguous with the previous range:
385 #2 - contiguous with previous
389 |--| |---| |------| ... |--|
394 If there's no overlap with the previous range, as in:
396 #3 - not overlapping and not contiguous
400 |--| |---| |------| ... |--|
407 #4 - R is the range with lowest offset
411 |--| |---| |------| ... |--|
416 ... we just push the new range to I.
418 All the 4 cases above need to consider that the new range may
419 also overlap several of the ranges that follow, or that R may be
420 contiguous with the following range, and merge. E.g.,
422 #5 - overlapping following ranges
425 |------------------------|
426 |--| |---| |------| ... |--|
435 |--| |---| |------| ... |--|
442 i
= VEC_lower_bound (range_s
, value
->unavailable
, &newr
, range_lessthan
);
445 struct range
*bef
= VEC_index (range_s
, value
->unavailable
, i
- 1);
447 if (ranges_overlap (bef
->offset
, bef
->length
, offset
, length
))
450 ULONGEST l
= min (bef
->offset
, offset
);
451 ULONGEST h
= max (bef
->offset
+ bef
->length
, offset
+ length
);
457 else if (offset
== bef
->offset
+ bef
->length
)
460 bef
->length
+= length
;
466 VEC_safe_insert (range_s
, value
->unavailable
, i
, &newr
);
472 VEC_safe_insert (range_s
, value
->unavailable
, i
, &newr
);
475 /* Check whether the ranges following the one we've just added or
476 touched can be folded in (#5 above). */
477 if (i
+ 1 < VEC_length (range_s
, value
->unavailable
))
484 /* Get the range we just touched. */
485 t
= VEC_index (range_s
, value
->unavailable
, i
);
489 for (; VEC_iterate (range_s
, value
->unavailable
, i
, r
); i
++)
490 if (r
->offset
<= t
->offset
+ t
->length
)
494 l
= min (t
->offset
, r
->offset
);
495 h
= max (t
->offset
+ t
->length
, r
->offset
+ r
->length
);
504 /* If we couldn't merge this one, we won't be able to
505 merge following ones either, since the ranges are
506 always sorted by OFFSET. */
511 VEC_block_remove (range_s
, value
->unavailable
, next
, removed
);
515 /* Find the first range in RANGES that overlaps the range defined by
516 OFFSET and LENGTH, starting at element POS in the RANGES vector,
517 Returns the index into RANGES where such overlapping range was
518 found, or -1 if none was found. */
521 find_first_range_overlap (VEC(range_s
) *ranges
, int pos
,
522 int offset
, int length
)
527 for (i
= pos
; VEC_iterate (range_s
, ranges
, i
, r
); i
++)
528 if (ranges_overlap (r
->offset
, r
->length
, offset
, length
))
535 value_available_contents_eq (const struct value
*val1
, int offset1
,
536 const struct value
*val2
, int offset2
,
539 int idx1
= 0, idx2
= 0;
541 /* This routine is used by printing routines, where we should
542 already have read the value. Note that we only know whether a
543 value chunk is available if we've tried to read it. */
544 gdb_assert (!val1
->lazy
&& !val2
->lazy
);
552 idx1
= find_first_range_overlap (val1
->unavailable
, idx1
,
554 idx2
= find_first_range_overlap (val2
->unavailable
, idx2
,
557 /* The usual case is for both values to be completely available. */
558 if (idx1
== -1 && idx2
== -1)
559 return (memcmp (val1
->contents
+ offset1
,
560 val2
->contents
+ offset2
,
562 /* The contents only match equal if the available set matches as
564 else if (idx1
== -1 || idx2
== -1)
567 gdb_assert (idx1
!= -1 && idx2
!= -1);
569 r1
= VEC_index (range_s
, val1
->unavailable
, idx1
);
570 r2
= VEC_index (range_s
, val2
->unavailable
, idx2
);
572 /* Get the unavailable windows intersected by the incoming
573 ranges. The first and last ranges that overlap the argument
574 range may be wider than said incoming arguments ranges. */
575 l1
= max (offset1
, r1
->offset
);
576 h1
= min (offset1
+ length
, r1
->offset
+ r1
->length
);
578 l2
= max (offset2
, r2
->offset
);
579 h2
= min (offset2
+ length
, r2
->offset
+ r2
->length
);
581 /* Make them relative to the respective start offsets, so we can
582 compare them for equality. */
589 /* Different availability, no match. */
590 if (l1
!= l2
|| h1
!= h2
)
593 /* Compare the _available_ contents. */
594 if (memcmp (val1
->contents
+ offset1
,
595 val2
->contents
+ offset2
,
607 /* Prototypes for local functions. */
609 static void show_values (char *, int);
611 static void show_convenience (char *, int);
614 /* The value-history records all the values printed
615 by print commands during this session. Each chunk
616 records 60 consecutive values. The first chunk on
617 the chain records the most recent values.
618 The total number of values is in value_history_count. */
620 #define VALUE_HISTORY_CHUNK 60
622 struct value_history_chunk
624 struct value_history_chunk
*next
;
625 struct value
*values
[VALUE_HISTORY_CHUNK
];
628 /* Chain of chunks now in use. */
630 static struct value_history_chunk
*value_history_chain
;
632 static int value_history_count
; /* Abs number of last entry stored. */
635 /* List of all value objects currently allocated
636 (except for those released by calls to release_value)
637 This is so they can be freed after each command. */
639 static struct value
*all_values
;
641 /* Allocate a lazy value for type TYPE. Its actual content is
642 "lazily" allocated too: the content field of the return value is
643 NULL; it will be allocated when it is fetched from the target. */
646 allocate_value_lazy (struct type
*type
)
650 /* Call check_typedef on our type to make sure that, if TYPE
651 is a TYPE_CODE_TYPEDEF, its length is set to the length
652 of the target type instead of zero. However, we do not
653 replace the typedef type by the target type, because we want
654 to keep the typedef in order to be able to set the VAL's type
655 description correctly. */
656 check_typedef (type
);
658 val
= (struct value
*) xzalloc (sizeof (struct value
));
659 val
->contents
= NULL
;
660 val
->next
= all_values
;
663 val
->enclosing_type
= type
;
664 VALUE_LVAL (val
) = not_lval
;
665 val
->location
.address
= 0;
666 VALUE_FRAME_ID (val
) = null_frame_id
;
670 VALUE_REGNUM (val
) = -1;
672 val
->optimized_out
= 0;
673 val
->embedded_offset
= 0;
674 val
->pointed_to_offset
= 0;
676 val
->initialized
= 1; /* Default to initialized. */
678 /* Values start out on the all_values chain. */
679 val
->reference_count
= 1;
684 /* Allocate the contents of VAL if it has not been allocated yet. */
687 allocate_value_contents (struct value
*val
)
690 val
->contents
= (gdb_byte
*) xzalloc (TYPE_LENGTH (val
->enclosing_type
));
693 /* Allocate a value and its contents for type TYPE. */
696 allocate_value (struct type
*type
)
698 struct value
*val
= allocate_value_lazy (type
);
700 allocate_value_contents (val
);
705 /* Allocate a value that has the correct length
706 for COUNT repetitions of type TYPE. */
709 allocate_repeat_value (struct type
*type
, int count
)
711 int low_bound
= current_language
->string_lower_bound
; /* ??? */
712 /* FIXME-type-allocation: need a way to free this type when we are
714 struct type
*array_type
715 = lookup_array_range_type (type
, low_bound
, count
+ low_bound
- 1);
717 return allocate_value (array_type
);
721 allocate_computed_value (struct type
*type
,
722 const struct lval_funcs
*funcs
,
725 struct value
*v
= allocate_value_lazy (type
);
727 VALUE_LVAL (v
) = lval_computed
;
728 v
->location
.computed
.funcs
= funcs
;
729 v
->location
.computed
.closure
= closure
;
734 /* Allocate NOT_LVAL value for type TYPE being OPTIMIZED_OUT. */
737 allocate_optimized_out_value (struct type
*type
)
739 struct value
*retval
= allocate_value_lazy (type
);
741 set_value_optimized_out (retval
, 1);
746 /* Accessor methods. */
749 value_next (struct value
*value
)
755 value_type (const struct value
*value
)
760 deprecated_set_value_type (struct value
*value
, struct type
*type
)
766 value_offset (const struct value
*value
)
768 return value
->offset
;
771 set_value_offset (struct value
*value
, int offset
)
773 value
->offset
= offset
;
777 value_bitpos (const struct value
*value
)
779 return value
->bitpos
;
782 set_value_bitpos (struct value
*value
, int bit
)
788 value_bitsize (const struct value
*value
)
790 return value
->bitsize
;
793 set_value_bitsize (struct value
*value
, int bit
)
795 value
->bitsize
= bit
;
799 value_parent (struct value
*value
)
801 return value
->parent
;
805 value_contents_raw (struct value
*value
)
807 allocate_value_contents (value
);
808 return value
->contents
+ value
->embedded_offset
;
812 value_contents_all_raw (struct value
*value
)
814 allocate_value_contents (value
);
815 return value
->contents
;
819 value_enclosing_type (struct value
*value
)
821 return value
->enclosing_type
;
825 require_not_optimized_out (const struct value
*value
)
827 if (value
->optimized_out
)
828 error (_("value has been optimized out"));
832 require_available (const struct value
*value
)
834 if (!VEC_empty (range_s
, value
->unavailable
))
835 throw_error (NOT_AVAILABLE_ERROR
, _("value is not available"));
839 value_contents_for_printing (struct value
*value
)
842 value_fetch_lazy (value
);
843 return value
->contents
;
847 value_contents_for_printing_const (const struct value
*value
)
849 gdb_assert (!value
->lazy
);
850 return value
->contents
;
854 value_contents_all (struct value
*value
)
856 const gdb_byte
*result
= value_contents_for_printing (value
);
857 require_not_optimized_out (value
);
858 require_available (value
);
862 /* Copy LENGTH bytes of SRC value's (all) contents
863 (value_contents_all) starting at SRC_OFFSET, into DST value's (all)
864 contents, starting at DST_OFFSET. If unavailable contents are
865 being copied from SRC, the corresponding DST contents are marked
866 unavailable accordingly. Neither DST nor SRC may be lazy
869 It is assumed the contents of DST in the [DST_OFFSET,
870 DST_OFFSET+LENGTH) range are wholly available. */
873 value_contents_copy_raw (struct value
*dst
, int dst_offset
,
874 struct value
*src
, int src_offset
, int length
)
879 /* A lazy DST would make that this copy operation useless, since as
880 soon as DST's contents were un-lazied (by a later value_contents
881 call, say), the contents would be overwritten. A lazy SRC would
882 mean we'd be copying garbage. */
883 gdb_assert (!dst
->lazy
&& !src
->lazy
);
885 /* The overwritten DST range gets unavailability ORed in, not
886 replaced. Make sure to remember to implement replacing if it
887 turns out actually necessary. */
888 gdb_assert (value_bytes_available (dst
, dst_offset
, length
));
891 memcpy (value_contents_all_raw (dst
) + dst_offset
,
892 value_contents_all_raw (src
) + src_offset
,
895 /* Copy the meta-data, adjusted. */
896 for (i
= 0; VEC_iterate (range_s
, src
->unavailable
, i
, r
); i
++)
900 l
= max (r
->offset
, src_offset
);
901 h
= min (r
->offset
+ r
->length
, src_offset
+ length
);
904 mark_value_bytes_unavailable (dst
,
905 dst_offset
+ (l
- src_offset
),
910 /* Copy LENGTH bytes of SRC value's (all) contents
911 (value_contents_all) starting at SRC_OFFSET byte, into DST value's
912 (all) contents, starting at DST_OFFSET. If unavailable contents
913 are being copied from SRC, the corresponding DST contents are
914 marked unavailable accordingly. DST must not be lazy. If SRC is
915 lazy, it will be fetched now. If SRC is not valid (is optimized
916 out), an error is thrown.
918 It is assumed the contents of DST in the [DST_OFFSET,
919 DST_OFFSET+LENGTH) range are wholly available. */
922 value_contents_copy (struct value
*dst
, int dst_offset
,
923 struct value
*src
, int src_offset
, int length
)
925 require_not_optimized_out (src
);
928 value_fetch_lazy (src
);
930 value_contents_copy_raw (dst
, dst_offset
, src
, src_offset
, length
);
934 value_lazy (struct value
*value
)
940 set_value_lazy (struct value
*value
, int val
)
946 value_stack (struct value
*value
)
952 set_value_stack (struct value
*value
, int val
)
958 value_contents (struct value
*value
)
960 const gdb_byte
*result
= value_contents_writeable (value
);
961 require_not_optimized_out (value
);
962 require_available (value
);
967 value_contents_writeable (struct value
*value
)
970 value_fetch_lazy (value
);
971 return value_contents_raw (value
);
974 /* Return non-zero if VAL1 and VAL2 have the same contents. Note that
975 this function is different from value_equal; in C the operator ==
976 can return 0 even if the two values being compared are equal. */
979 value_contents_equal (struct value
*val1
, struct value
*val2
)
985 type1
= check_typedef (value_type (val1
));
986 type2
= check_typedef (value_type (val2
));
987 len
= TYPE_LENGTH (type1
);
988 if (len
!= TYPE_LENGTH (type2
))
991 return (memcmp (value_contents (val1
), value_contents (val2
), len
) == 0);
995 value_optimized_out (struct value
*value
)
997 return value
->optimized_out
;
1001 set_value_optimized_out (struct value
*value
, int val
)
1003 value
->optimized_out
= val
;
1007 value_entirely_optimized_out (const struct value
*value
)
1009 if (!value
->optimized_out
)
1011 if (value
->lval
!= lval_computed
1012 || !value
->location
.computed
.funcs
->check_any_valid
)
1014 return !value
->location
.computed
.funcs
->check_any_valid (value
);
1018 value_bits_valid (const struct value
*value
, int offset
, int length
)
1020 if (!value
->optimized_out
)
1022 if (value
->lval
!= lval_computed
1023 || !value
->location
.computed
.funcs
->check_validity
)
1025 return value
->location
.computed
.funcs
->check_validity (value
, offset
,
1030 value_bits_synthetic_pointer (const struct value
*value
,
1031 int offset
, int length
)
1033 if (value
->lval
!= lval_computed
1034 || !value
->location
.computed
.funcs
->check_synthetic_pointer
)
1036 return value
->location
.computed
.funcs
->check_synthetic_pointer (value
,
1042 value_embedded_offset (struct value
*value
)
1044 return value
->embedded_offset
;
1048 set_value_embedded_offset (struct value
*value
, int val
)
1050 value
->embedded_offset
= val
;
1054 value_pointed_to_offset (struct value
*value
)
1056 return value
->pointed_to_offset
;
1060 set_value_pointed_to_offset (struct value
*value
, int val
)
1062 value
->pointed_to_offset
= val
;
1065 const struct lval_funcs
*
1066 value_computed_funcs (const struct value
*v
)
1068 gdb_assert (value_lval_const (v
) == lval_computed
);
1070 return v
->location
.computed
.funcs
;
1074 value_computed_closure (const struct value
*v
)
1076 gdb_assert (v
->lval
== lval_computed
);
1078 return v
->location
.computed
.closure
;
1082 deprecated_value_lval_hack (struct value
*value
)
1084 return &value
->lval
;
1088 value_lval_const (const struct value
*value
)
1094 value_address (const struct value
*value
)
1096 if (value
->lval
== lval_internalvar
1097 || value
->lval
== lval_internalvar_component
)
1099 return value
->location
.address
+ value
->offset
;
1103 value_raw_address (struct value
*value
)
1105 if (value
->lval
== lval_internalvar
1106 || value
->lval
== lval_internalvar_component
)
1108 return value
->location
.address
;
1112 set_value_address (struct value
*value
, CORE_ADDR addr
)
1114 gdb_assert (value
->lval
!= lval_internalvar
1115 && value
->lval
!= lval_internalvar_component
);
1116 value
->location
.address
= addr
;
1119 struct internalvar
**
1120 deprecated_value_internalvar_hack (struct value
*value
)
1122 return &value
->location
.internalvar
;
1126 deprecated_value_frame_id_hack (struct value
*value
)
1128 return &value
->frame_id
;
1132 deprecated_value_regnum_hack (struct value
*value
)
1134 return &value
->regnum
;
1138 deprecated_value_modifiable (struct value
*value
)
1140 return value
->modifiable
;
1143 deprecated_set_value_modifiable (struct value
*value
, int modifiable
)
1145 value
->modifiable
= modifiable
;
1148 /* Return a mark in the value chain. All values allocated after the
1149 mark is obtained (except for those released) are subject to being freed
1150 if a subsequent value_free_to_mark is passed the mark. */
1157 /* Take a reference to VAL. VAL will not be deallocated until all
1158 references are released. */
1161 value_incref (struct value
*val
)
1163 val
->reference_count
++;
1166 /* Release a reference to VAL, which was acquired with value_incref.
1167 This function is also called to deallocate values from the value
1171 value_free (struct value
*val
)
1175 gdb_assert (val
->reference_count
> 0);
1176 val
->reference_count
--;
1177 if (val
->reference_count
> 0)
1180 /* If there's an associated parent value, drop our reference to
1182 if (val
->parent
!= NULL
)
1183 value_free (val
->parent
);
1185 if (VALUE_LVAL (val
) == lval_computed
)
1187 const struct lval_funcs
*funcs
= val
->location
.computed
.funcs
;
1189 if (funcs
->free_closure
)
1190 funcs
->free_closure (val
);
1193 xfree (val
->contents
);
1194 VEC_free (range_s
, val
->unavailable
);
1199 /* Free all values allocated since MARK was obtained by value_mark
1200 (except for those released). */
1202 value_free_to_mark (struct value
*mark
)
1207 for (val
= all_values
; val
&& val
!= mark
; val
= next
)
1215 /* Free all the values that have been allocated (except for those released).
1216 Call after each command, successful or not.
1217 In practice this is called before each command, which is sufficient. */
1220 free_all_values (void)
1225 for (val
= all_values
; val
; val
= next
)
1234 /* Frees all the elements in a chain of values. */
1237 free_value_chain (struct value
*v
)
1243 next
= value_next (v
);
1248 /* Remove VAL from the chain all_values
1249 so it will not be freed automatically. */
1252 release_value (struct value
*val
)
1256 if (all_values
== val
)
1258 all_values
= val
->next
;
1263 for (v
= all_values
; v
; v
= v
->next
)
1267 v
->next
= val
->next
;
1274 /* Release all values up to mark */
1276 value_release_to_mark (struct value
*mark
)
1281 for (val
= next
= all_values
; next
; next
= next
->next
)
1282 if (next
->next
== mark
)
1284 all_values
= next
->next
;
1292 /* Return a copy of the value ARG.
1293 It contains the same contents, for same memory address,
1294 but it's a different block of storage. */
1297 value_copy (struct value
*arg
)
1299 struct type
*encl_type
= value_enclosing_type (arg
);
1302 if (value_lazy (arg
))
1303 val
= allocate_value_lazy (encl_type
);
1305 val
= allocate_value (encl_type
);
1306 val
->type
= arg
->type
;
1307 VALUE_LVAL (val
) = VALUE_LVAL (arg
);
1308 val
->location
= arg
->location
;
1309 val
->offset
= arg
->offset
;
1310 val
->bitpos
= arg
->bitpos
;
1311 val
->bitsize
= arg
->bitsize
;
1312 VALUE_FRAME_ID (val
) = VALUE_FRAME_ID (arg
);
1313 VALUE_REGNUM (val
) = VALUE_REGNUM (arg
);
1314 val
->lazy
= arg
->lazy
;
1315 val
->optimized_out
= arg
->optimized_out
;
1316 val
->embedded_offset
= value_embedded_offset (arg
);
1317 val
->pointed_to_offset
= arg
->pointed_to_offset
;
1318 val
->modifiable
= arg
->modifiable
;
1319 if (!value_lazy (val
))
1321 memcpy (value_contents_all_raw (val
), value_contents_all_raw (arg
),
1322 TYPE_LENGTH (value_enclosing_type (arg
)));
1325 val
->unavailable
= VEC_copy (range_s
, arg
->unavailable
);
1326 val
->parent
= arg
->parent
;
1328 value_incref (val
->parent
);
1329 if (VALUE_LVAL (val
) == lval_computed
)
1331 const struct lval_funcs
*funcs
= val
->location
.computed
.funcs
;
1333 if (funcs
->copy_closure
)
1334 val
->location
.computed
.closure
= funcs
->copy_closure (val
);
1339 /* Return a version of ARG that is non-lvalue. */
1342 value_non_lval (struct value
*arg
)
1344 if (VALUE_LVAL (arg
) != not_lval
)
1346 struct type
*enc_type
= value_enclosing_type (arg
);
1347 struct value
*val
= allocate_value (enc_type
);
1349 memcpy (value_contents_all_raw (val
), value_contents_all (arg
),
1350 TYPE_LENGTH (enc_type
));
1351 val
->type
= arg
->type
;
1352 set_value_embedded_offset (val
, value_embedded_offset (arg
));
1353 set_value_pointed_to_offset (val
, value_pointed_to_offset (arg
));
1360 set_value_component_location (struct value
*component
,
1361 const struct value
*whole
)
1363 if (whole
->lval
== lval_internalvar
)
1364 VALUE_LVAL (component
) = lval_internalvar_component
;
1366 VALUE_LVAL (component
) = whole
->lval
;
1368 component
->location
= whole
->location
;
1369 if (whole
->lval
== lval_computed
)
1371 const struct lval_funcs
*funcs
= whole
->location
.computed
.funcs
;
1373 if (funcs
->copy_closure
)
1374 component
->location
.computed
.closure
= funcs
->copy_closure (whole
);
1379 /* Access to the value history. */
1381 /* Record a new value in the value history.
1382 Returns the absolute history index of the entry.
1383 Result of -1 indicates the value was not saved; otherwise it is the
1384 value history index of this new item. */
1387 record_latest_value (struct value
*val
)
1391 /* We don't want this value to have anything to do with the inferior anymore.
1392 In particular, "set $1 = 50" should not affect the variable from which
1393 the value was taken, and fast watchpoints should be able to assume that
1394 a value on the value history never changes. */
1395 if (value_lazy (val
))
1396 value_fetch_lazy (val
);
1397 /* We preserve VALUE_LVAL so that the user can find out where it was fetched
1398 from. This is a bit dubious, because then *&$1 does not just return $1
1399 but the current contents of that location. c'est la vie... */
1400 val
->modifiable
= 0;
1401 release_value (val
);
1403 /* Here we treat value_history_count as origin-zero
1404 and applying to the value being stored now. */
1406 i
= value_history_count
% VALUE_HISTORY_CHUNK
;
1409 struct value_history_chunk
*new
1410 = (struct value_history_chunk
*)
1412 xmalloc (sizeof (struct value_history_chunk
));
1413 memset (new->values
, 0, sizeof new->values
);
1414 new->next
= value_history_chain
;
1415 value_history_chain
= new;
1418 value_history_chain
->values
[i
] = val
;
1420 /* Now we regard value_history_count as origin-one
1421 and applying to the value just stored. */
1423 return ++value_history_count
;
1426 /* Return a copy of the value in the history with sequence number NUM. */
1429 access_value_history (int num
)
1431 struct value_history_chunk
*chunk
;
1436 absnum
+= value_history_count
;
1441 error (_("The history is empty."));
1443 error (_("There is only one value in the history."));
1445 error (_("History does not go back to $$%d."), -num
);
1447 if (absnum
> value_history_count
)
1448 error (_("History has not yet reached $%d."), absnum
);
1452 /* Now absnum is always absolute and origin zero. */
1454 chunk
= value_history_chain
;
1455 for (i
= (value_history_count
- 1) / VALUE_HISTORY_CHUNK
1456 - absnum
/ VALUE_HISTORY_CHUNK
;
1458 chunk
= chunk
->next
;
1460 return value_copy (chunk
->values
[absnum
% VALUE_HISTORY_CHUNK
]);
1464 show_values (char *num_exp
, int from_tty
)
1472 /* "show values +" should print from the stored position.
1473 "show values <exp>" should print around value number <exp>. */
1474 if (num_exp
[0] != '+' || num_exp
[1] != '\0')
1475 num
= parse_and_eval_long (num_exp
) - 5;
1479 /* "show values" means print the last 10 values. */
1480 num
= value_history_count
- 9;
1486 for (i
= num
; i
< num
+ 10 && i
<= value_history_count
; i
++)
1488 struct value_print_options opts
;
1490 val
= access_value_history (i
);
1491 printf_filtered (("$%d = "), i
);
1492 get_user_print_options (&opts
);
1493 value_print (val
, gdb_stdout
, &opts
);
1494 printf_filtered (("\n"));
1497 /* The next "show values +" should start after what we just printed. */
1500 /* Hitting just return after this command should do the same thing as
1501 "show values +". If num_exp is null, this is unnecessary, since
1502 "show values +" is not useful after "show values". */
1503 if (from_tty
&& num_exp
)
1510 /* Internal variables. These are variables within the debugger
1511 that hold values assigned by debugger commands.
1512 The user refers to them with a '$' prefix
1513 that does not appear in the variable names stored internally. */
1517 struct internalvar
*next
;
1520 /* We support various different kinds of content of an internal variable.
1521 enum internalvar_kind specifies the kind, and union internalvar_data
1522 provides the data associated with this particular kind. */
1524 enum internalvar_kind
1526 /* The internal variable is empty. */
1529 /* The value of the internal variable is provided directly as
1530 a GDB value object. */
1533 /* A fresh value is computed via a call-back routine on every
1534 access to the internal variable. */
1535 INTERNALVAR_MAKE_VALUE
,
1537 /* The internal variable holds a GDB internal convenience function. */
1538 INTERNALVAR_FUNCTION
,
1540 /* The variable holds an integer value. */
1541 INTERNALVAR_INTEGER
,
1543 /* The variable holds a GDB-provided string. */
1548 union internalvar_data
1550 /* A value object used with INTERNALVAR_VALUE. */
1551 struct value
*value
;
1553 /* The call-back routine used with INTERNALVAR_MAKE_VALUE. */
1554 internalvar_make_value make_value
;
1556 /* The internal function used with INTERNALVAR_FUNCTION. */
1559 struct internal_function
*function
;
1560 /* True if this is the canonical name for the function. */
1564 /* An integer value used with INTERNALVAR_INTEGER. */
1567 /* If type is non-NULL, it will be used as the type to generate
1568 a value for this internal variable. If type is NULL, a default
1569 integer type for the architecture is used. */
1574 /* A string value used with INTERNALVAR_STRING. */
1579 static struct internalvar
*internalvars
;
1581 /* If the variable does not already exist create it and give it the
1582 value given. If no value is given then the default is zero. */
1584 init_if_undefined_command (char* args
, int from_tty
)
1586 struct internalvar
* intvar
;
1588 /* Parse the expression - this is taken from set_command(). */
1589 struct expression
*expr
= parse_expression (args
);
1590 register struct cleanup
*old_chain
=
1591 make_cleanup (free_current_contents
, &expr
);
1593 /* Validate the expression.
1594 Was the expression an assignment?
1595 Or even an expression at all? */
1596 if (expr
->nelts
== 0 || expr
->elts
[0].opcode
!= BINOP_ASSIGN
)
1597 error (_("Init-if-undefined requires an assignment expression."));
1599 /* Extract the variable from the parsed expression.
1600 In the case of an assign the lvalue will be in elts[1] and elts[2]. */
1601 if (expr
->elts
[1].opcode
!= OP_INTERNALVAR
)
1602 error (_("The first parameter to init-if-undefined "
1603 "should be a GDB variable."));
1604 intvar
= expr
->elts
[2].internalvar
;
1606 /* Only evaluate the expression if the lvalue is void.
1607 This may still fail if the expresssion is invalid. */
1608 if (intvar
->kind
== INTERNALVAR_VOID
)
1609 evaluate_expression (expr
);
1611 do_cleanups (old_chain
);
1615 /* Look up an internal variable with name NAME. NAME should not
1616 normally include a dollar sign.
1618 If the specified internal variable does not exist,
1619 the return value is NULL. */
1621 struct internalvar
*
1622 lookup_only_internalvar (const char *name
)
1624 struct internalvar
*var
;
1626 for (var
= internalvars
; var
; var
= var
->next
)
1627 if (strcmp (var
->name
, name
) == 0)
1634 /* Create an internal variable with name NAME and with a void value.
1635 NAME should not normally include a dollar sign. */
1637 struct internalvar
*
1638 create_internalvar (const char *name
)
1640 struct internalvar
*var
;
1642 var
= (struct internalvar
*) xmalloc (sizeof (struct internalvar
));
1643 var
->name
= concat (name
, (char *)NULL
);
1644 var
->kind
= INTERNALVAR_VOID
;
1645 var
->next
= internalvars
;
1650 /* Create an internal variable with name NAME and register FUN as the
1651 function that value_of_internalvar uses to create a value whenever
1652 this variable is referenced. NAME should not normally include a
1655 struct internalvar
*
1656 create_internalvar_type_lazy (char *name
, internalvar_make_value fun
)
1658 struct internalvar
*var
= create_internalvar (name
);
1660 var
->kind
= INTERNALVAR_MAKE_VALUE
;
1661 var
->u
.make_value
= fun
;
1665 /* Look up an internal variable with name NAME. NAME should not
1666 normally include a dollar sign.
1668 If the specified internal variable does not exist,
1669 one is created, with a void value. */
1671 struct internalvar
*
1672 lookup_internalvar (const char *name
)
1674 struct internalvar
*var
;
1676 var
= lookup_only_internalvar (name
);
1680 return create_internalvar (name
);
1683 /* Return current value of internal variable VAR. For variables that
1684 are not inherently typed, use a value type appropriate for GDBARCH. */
1687 value_of_internalvar (struct gdbarch
*gdbarch
, struct internalvar
*var
)
1690 struct trace_state_variable
*tsv
;
1692 /* If there is a trace state variable of the same name, assume that
1693 is what we really want to see. */
1694 tsv
= find_trace_state_variable (var
->name
);
1697 tsv
->value_known
= target_get_trace_state_variable_value (tsv
->number
,
1699 if (tsv
->value_known
)
1700 val
= value_from_longest (builtin_type (gdbarch
)->builtin_int64
,
1703 val
= allocate_value (builtin_type (gdbarch
)->builtin_void
);
1709 case INTERNALVAR_VOID
:
1710 val
= allocate_value (builtin_type (gdbarch
)->builtin_void
);
1713 case INTERNALVAR_FUNCTION
:
1714 val
= allocate_value (builtin_type (gdbarch
)->internal_fn
);
1717 case INTERNALVAR_INTEGER
:
1718 if (!var
->u
.integer
.type
)
1719 val
= value_from_longest (builtin_type (gdbarch
)->builtin_int
,
1720 var
->u
.integer
.val
);
1722 val
= value_from_longest (var
->u
.integer
.type
, var
->u
.integer
.val
);
1725 case INTERNALVAR_STRING
:
1726 val
= value_cstring (var
->u
.string
, strlen (var
->u
.string
),
1727 builtin_type (gdbarch
)->builtin_char
);
1730 case INTERNALVAR_VALUE
:
1731 val
= value_copy (var
->u
.value
);
1732 if (value_lazy (val
))
1733 value_fetch_lazy (val
);
1736 case INTERNALVAR_MAKE_VALUE
:
1737 val
= (*var
->u
.make_value
) (gdbarch
, var
);
1741 internal_error (__FILE__
, __LINE__
, _("bad kind"));
1744 /* Change the VALUE_LVAL to lval_internalvar so that future operations
1745 on this value go back to affect the original internal variable.
1747 Do not do this for INTERNALVAR_MAKE_VALUE variables, as those have
1748 no underlying modifyable state in the internal variable.
1750 Likewise, if the variable's value is a computed lvalue, we want
1751 references to it to produce another computed lvalue, where
1752 references and assignments actually operate through the
1753 computed value's functions.
1755 This means that internal variables with computed values
1756 behave a little differently from other internal variables:
1757 assignments to them don't just replace the previous value
1758 altogether. At the moment, this seems like the behavior we
1761 if (var
->kind
!= INTERNALVAR_MAKE_VALUE
1762 && val
->lval
!= lval_computed
)
1764 VALUE_LVAL (val
) = lval_internalvar
;
1765 VALUE_INTERNALVAR (val
) = var
;
1772 get_internalvar_integer (struct internalvar
*var
, LONGEST
*result
)
1774 if (var
->kind
== INTERNALVAR_INTEGER
)
1776 *result
= var
->u
.integer
.val
;
1780 if (var
->kind
== INTERNALVAR_VALUE
)
1782 struct type
*type
= check_typedef (value_type (var
->u
.value
));
1784 if (TYPE_CODE (type
) == TYPE_CODE_INT
)
1786 *result
= value_as_long (var
->u
.value
);
1795 get_internalvar_function (struct internalvar
*var
,
1796 struct internal_function
**result
)
1800 case INTERNALVAR_FUNCTION
:
1801 *result
= var
->u
.fn
.function
;
1810 set_internalvar_component (struct internalvar
*var
, int offset
, int bitpos
,
1811 int bitsize
, struct value
*newval
)
1817 case INTERNALVAR_VALUE
:
1818 addr
= value_contents_writeable (var
->u
.value
);
1821 modify_field (value_type (var
->u
.value
), addr
+ offset
,
1822 value_as_long (newval
), bitpos
, bitsize
);
1824 memcpy (addr
+ offset
, value_contents (newval
),
1825 TYPE_LENGTH (value_type (newval
)));
1829 /* We can never get a component of any other kind. */
1830 internal_error (__FILE__
, __LINE__
, _("set_internalvar_component"));
1835 set_internalvar (struct internalvar
*var
, struct value
*val
)
1837 enum internalvar_kind new_kind
;
1838 union internalvar_data new_data
= { 0 };
1840 if (var
->kind
== INTERNALVAR_FUNCTION
&& var
->u
.fn
.canonical
)
1841 error (_("Cannot overwrite convenience function %s"), var
->name
);
1843 /* Prepare new contents. */
1844 switch (TYPE_CODE (check_typedef (value_type (val
))))
1846 case TYPE_CODE_VOID
:
1847 new_kind
= INTERNALVAR_VOID
;
1850 case TYPE_CODE_INTERNAL_FUNCTION
:
1851 gdb_assert (VALUE_LVAL (val
) == lval_internalvar
);
1852 new_kind
= INTERNALVAR_FUNCTION
;
1853 get_internalvar_function (VALUE_INTERNALVAR (val
),
1854 &new_data
.fn
.function
);
1855 /* Copies created here are never canonical. */
1859 new_kind
= INTERNALVAR_VALUE
;
1860 new_data
.value
= value_copy (val
);
1861 new_data
.value
->modifiable
= 1;
1863 /* Force the value to be fetched from the target now, to avoid problems
1864 later when this internalvar is referenced and the target is gone or
1866 if (value_lazy (new_data
.value
))
1867 value_fetch_lazy (new_data
.value
);
1869 /* Release the value from the value chain to prevent it from being
1870 deleted by free_all_values. From here on this function should not
1871 call error () until new_data is installed into the var->u to avoid
1873 release_value (new_data
.value
);
1877 /* Clean up old contents. */
1878 clear_internalvar (var
);
1881 var
->kind
= new_kind
;
1883 /* End code which must not call error(). */
1887 set_internalvar_integer (struct internalvar
*var
, LONGEST l
)
1889 /* Clean up old contents. */
1890 clear_internalvar (var
);
1892 var
->kind
= INTERNALVAR_INTEGER
;
1893 var
->u
.integer
.type
= NULL
;
1894 var
->u
.integer
.val
= l
;
1898 set_internalvar_string (struct internalvar
*var
, const char *string
)
1900 /* Clean up old contents. */
1901 clear_internalvar (var
);
1903 var
->kind
= INTERNALVAR_STRING
;
1904 var
->u
.string
= xstrdup (string
);
1908 set_internalvar_function (struct internalvar
*var
, struct internal_function
*f
)
1910 /* Clean up old contents. */
1911 clear_internalvar (var
);
1913 var
->kind
= INTERNALVAR_FUNCTION
;
1914 var
->u
.fn
.function
= f
;
1915 var
->u
.fn
.canonical
= 1;
1916 /* Variables installed here are always the canonical version. */
1920 clear_internalvar (struct internalvar
*var
)
1922 /* Clean up old contents. */
1925 case INTERNALVAR_VALUE
:
1926 value_free (var
->u
.value
);
1929 case INTERNALVAR_STRING
:
1930 xfree (var
->u
.string
);
1937 /* Reset to void kind. */
1938 var
->kind
= INTERNALVAR_VOID
;
1942 internalvar_name (struct internalvar
*var
)
1947 static struct internal_function
*
1948 create_internal_function (const char *name
,
1949 internal_function_fn handler
, void *cookie
)
1951 struct internal_function
*ifn
= XNEW (struct internal_function
);
1953 ifn
->name
= xstrdup (name
);
1954 ifn
->handler
= handler
;
1955 ifn
->cookie
= cookie
;
1960 value_internal_function_name (struct value
*val
)
1962 struct internal_function
*ifn
;
1965 gdb_assert (VALUE_LVAL (val
) == lval_internalvar
);
1966 result
= get_internalvar_function (VALUE_INTERNALVAR (val
), &ifn
);
1967 gdb_assert (result
);
1973 call_internal_function (struct gdbarch
*gdbarch
,
1974 const struct language_defn
*language
,
1975 struct value
*func
, int argc
, struct value
**argv
)
1977 struct internal_function
*ifn
;
1980 gdb_assert (VALUE_LVAL (func
) == lval_internalvar
);
1981 result
= get_internalvar_function (VALUE_INTERNALVAR (func
), &ifn
);
1982 gdb_assert (result
);
1984 return (*ifn
->handler
) (gdbarch
, language
, ifn
->cookie
, argc
, argv
);
1987 /* The 'function' command. This does nothing -- it is just a
1988 placeholder to let "help function NAME" work. This is also used as
1989 the implementation of the sub-command that is created when
1990 registering an internal function. */
1992 function_command (char *command
, int from_tty
)
1997 /* Clean up if an internal function's command is destroyed. */
1999 function_destroyer (struct cmd_list_element
*self
, void *ignore
)
2005 /* Add a new internal function. NAME is the name of the function; DOC
2006 is a documentation string describing the function. HANDLER is
2007 called when the function is invoked. COOKIE is an arbitrary
2008 pointer which is passed to HANDLER and is intended for "user
2011 add_internal_function (const char *name
, const char *doc
,
2012 internal_function_fn handler
, void *cookie
)
2014 struct cmd_list_element
*cmd
;
2015 struct internal_function
*ifn
;
2016 struct internalvar
*var
= lookup_internalvar (name
);
2018 ifn
= create_internal_function (name
, handler
, cookie
);
2019 set_internalvar_function (var
, ifn
);
2021 cmd
= add_cmd (xstrdup (name
), no_class
, function_command
, (char *) doc
,
2023 cmd
->destroyer
= function_destroyer
;
2026 /* Update VALUE before discarding OBJFILE. COPIED_TYPES is used to
2027 prevent cycles / duplicates. */
2030 preserve_one_value (struct value
*value
, struct objfile
*objfile
,
2031 htab_t copied_types
)
2033 if (TYPE_OBJFILE (value
->type
) == objfile
)
2034 value
->type
= copy_type_recursive (objfile
, value
->type
, copied_types
);
2036 if (TYPE_OBJFILE (value
->enclosing_type
) == objfile
)
2037 value
->enclosing_type
= copy_type_recursive (objfile
,
2038 value
->enclosing_type
,
2042 /* Likewise for internal variable VAR. */
2045 preserve_one_internalvar (struct internalvar
*var
, struct objfile
*objfile
,
2046 htab_t copied_types
)
2050 case INTERNALVAR_INTEGER
:
2051 if (var
->u
.integer
.type
&& TYPE_OBJFILE (var
->u
.integer
.type
) == objfile
)
2053 = copy_type_recursive (objfile
, var
->u
.integer
.type
, copied_types
);
2056 case INTERNALVAR_VALUE
:
2057 preserve_one_value (var
->u
.value
, objfile
, copied_types
);
2062 /* Update the internal variables and value history when OBJFILE is
2063 discarded; we must copy the types out of the objfile. New global types
2064 will be created for every convenience variable which currently points to
2065 this objfile's types, and the convenience variables will be adjusted to
2066 use the new global types. */
2069 preserve_values (struct objfile
*objfile
)
2071 htab_t copied_types
;
2072 struct value_history_chunk
*cur
;
2073 struct internalvar
*var
;
2076 /* Create the hash table. We allocate on the objfile's obstack, since
2077 it is soon to be deleted. */
2078 copied_types
= create_copied_types_hash (objfile
);
2080 for (cur
= value_history_chain
; cur
; cur
= cur
->next
)
2081 for (i
= 0; i
< VALUE_HISTORY_CHUNK
; i
++)
2083 preserve_one_value (cur
->values
[i
], objfile
, copied_types
);
2085 for (var
= internalvars
; var
; var
= var
->next
)
2086 preserve_one_internalvar (var
, objfile
, copied_types
);
2088 preserve_python_values (objfile
, copied_types
);
2090 htab_delete (copied_types
);
2094 show_convenience (char *ignore
, int from_tty
)
2096 struct gdbarch
*gdbarch
= get_current_arch ();
2097 struct internalvar
*var
;
2099 struct value_print_options opts
;
2101 get_user_print_options (&opts
);
2102 for (var
= internalvars
; var
; var
= var
->next
)
2104 volatile struct gdb_exception ex
;
2110 printf_filtered (("$%s = "), var
->name
);
2112 TRY_CATCH (ex
, RETURN_MASK_ERROR
)
2116 val
= value_of_internalvar (gdbarch
, var
);
2117 value_print (val
, gdb_stdout
, &opts
);
2120 fprintf_filtered (gdb_stdout
, _("<error: %s>"), ex
.message
);
2121 printf_filtered (("\n"));
2124 printf_unfiltered (_("No debugger convenience variables now defined.\n"
2125 "Convenience variables have "
2126 "names starting with \"$\";\n"
2127 "use \"set\" as in \"set "
2128 "$foo = 5\" to define them.\n"));
2131 /* Extract a value as a C number (either long or double).
2132 Knows how to convert fixed values to double, or
2133 floating values to long.
2134 Does not deallocate the value. */
2137 value_as_long (struct value
*val
)
2139 /* This coerces arrays and functions, which is necessary (e.g.
2140 in disassemble_command). It also dereferences references, which
2141 I suspect is the most logical thing to do. */
2142 val
= coerce_array (val
);
2143 return unpack_long (value_type (val
), value_contents (val
));
2147 value_as_double (struct value
*val
)
2152 foo
= unpack_double (value_type (val
), value_contents (val
), &inv
);
2154 error (_("Invalid floating value found in program."));
2158 /* Extract a value as a C pointer. Does not deallocate the value.
2159 Note that val's type may not actually be a pointer; value_as_long
2160 handles all the cases. */
2162 value_as_address (struct value
*val
)
2164 struct gdbarch
*gdbarch
= get_type_arch (value_type (val
));
2166 /* Assume a CORE_ADDR can fit in a LONGEST (for now). Not sure
2167 whether we want this to be true eventually. */
2169 /* gdbarch_addr_bits_remove is wrong if we are being called for a
2170 non-address (e.g. argument to "signal", "info break", etc.), or
2171 for pointers to char, in which the low bits *are* significant. */
2172 return gdbarch_addr_bits_remove (gdbarch
, value_as_long (val
));
2175 /* There are several targets (IA-64, PowerPC, and others) which
2176 don't represent pointers to functions as simply the address of
2177 the function's entry point. For example, on the IA-64, a
2178 function pointer points to a two-word descriptor, generated by
2179 the linker, which contains the function's entry point, and the
2180 value the IA-64 "global pointer" register should have --- to
2181 support position-independent code. The linker generates
2182 descriptors only for those functions whose addresses are taken.
2184 On such targets, it's difficult for GDB to convert an arbitrary
2185 function address into a function pointer; it has to either find
2186 an existing descriptor for that function, or call malloc and
2187 build its own. On some targets, it is impossible for GDB to
2188 build a descriptor at all: the descriptor must contain a jump
2189 instruction; data memory cannot be executed; and code memory
2192 Upon entry to this function, if VAL is a value of type `function'
2193 (that is, TYPE_CODE (VALUE_TYPE (val)) == TYPE_CODE_FUNC), then
2194 value_address (val) is the address of the function. This is what
2195 you'll get if you evaluate an expression like `main'. The call
2196 to COERCE_ARRAY below actually does all the usual unary
2197 conversions, which includes converting values of type `function'
2198 to `pointer to function'. This is the challenging conversion
2199 discussed above. Then, `unpack_long' will convert that pointer
2200 back into an address.
2202 So, suppose the user types `disassemble foo' on an architecture
2203 with a strange function pointer representation, on which GDB
2204 cannot build its own descriptors, and suppose further that `foo'
2205 has no linker-built descriptor. The address->pointer conversion
2206 will signal an error and prevent the command from running, even
2207 though the next step would have been to convert the pointer
2208 directly back into the same address.
2210 The following shortcut avoids this whole mess. If VAL is a
2211 function, just return its address directly. */
2212 if (TYPE_CODE (value_type (val
)) == TYPE_CODE_FUNC
2213 || TYPE_CODE (value_type (val
)) == TYPE_CODE_METHOD
)
2214 return value_address (val
);
2216 val
= coerce_array (val
);
2218 /* Some architectures (e.g. Harvard), map instruction and data
2219 addresses onto a single large unified address space. For
2220 instance: An architecture may consider a large integer in the
2221 range 0x10000000 .. 0x1000ffff to already represent a data
2222 addresses (hence not need a pointer to address conversion) while
2223 a small integer would still need to be converted integer to
2224 pointer to address. Just assume such architectures handle all
2225 integer conversions in a single function. */
2229 I think INTEGER_TO_ADDRESS is a good idea as proposed --- but we
2230 must admonish GDB hackers to make sure its behavior matches the
2231 compiler's, whenever possible.
2233 In general, I think GDB should evaluate expressions the same way
2234 the compiler does. When the user copies an expression out of
2235 their source code and hands it to a `print' command, they should
2236 get the same value the compiler would have computed. Any
2237 deviation from this rule can cause major confusion and annoyance,
2238 and needs to be justified carefully. In other words, GDB doesn't
2239 really have the freedom to do these conversions in clever and
2242 AndrewC pointed out that users aren't complaining about how GDB
2243 casts integers to pointers; they are complaining that they can't
2244 take an address from a disassembly listing and give it to `x/i'.
2245 This is certainly important.
2247 Adding an architecture method like integer_to_address() certainly
2248 makes it possible for GDB to "get it right" in all circumstances
2249 --- the target has complete control over how things get done, so
2250 people can Do The Right Thing for their target without breaking
2251 anyone else. The standard doesn't specify how integers get
2252 converted to pointers; usually, the ABI doesn't either, but
2253 ABI-specific code is a more reasonable place to handle it. */
2255 if (TYPE_CODE (value_type (val
)) != TYPE_CODE_PTR
2256 && TYPE_CODE (value_type (val
)) != TYPE_CODE_REF
2257 && gdbarch_integer_to_address_p (gdbarch
))
2258 return gdbarch_integer_to_address (gdbarch
, value_type (val
),
2259 value_contents (val
));
2261 return unpack_long (value_type (val
), value_contents (val
));
2265 /* Unpack raw data (copied from debugee, target byte order) at VALADDR
2266 as a long, or as a double, assuming the raw data is described
2267 by type TYPE. Knows how to convert different sizes of values
2268 and can convert between fixed and floating point. We don't assume
2269 any alignment for the raw data. Return value is in host byte order.
2271 If you want functions and arrays to be coerced to pointers, and
2272 references to be dereferenced, call value_as_long() instead.
2274 C++: It is assumed that the front-end has taken care of
2275 all matters concerning pointers to members. A pointer
2276 to member which reaches here is considered to be equivalent
2277 to an INT (or some size). After all, it is only an offset. */
2280 unpack_long (struct type
*type
, const gdb_byte
*valaddr
)
2282 enum bfd_endian byte_order
= gdbarch_byte_order (get_type_arch (type
));
2283 enum type_code code
= TYPE_CODE (type
);
2284 int len
= TYPE_LENGTH (type
);
2285 int nosign
= TYPE_UNSIGNED (type
);
2289 case TYPE_CODE_TYPEDEF
:
2290 return unpack_long (check_typedef (type
), valaddr
);
2291 case TYPE_CODE_ENUM
:
2292 case TYPE_CODE_FLAGS
:
2293 case TYPE_CODE_BOOL
:
2295 case TYPE_CODE_CHAR
:
2296 case TYPE_CODE_RANGE
:
2297 case TYPE_CODE_MEMBERPTR
:
2299 return extract_unsigned_integer (valaddr
, len
, byte_order
);
2301 return extract_signed_integer (valaddr
, len
, byte_order
);
2304 return extract_typed_floating (valaddr
, type
);
2306 case TYPE_CODE_DECFLOAT
:
2307 /* libdecnumber has a function to convert from decimal to integer, but
2308 it doesn't work when the decimal number has a fractional part. */
2309 return decimal_to_doublest (valaddr
, len
, byte_order
);
2313 /* Assume a CORE_ADDR can fit in a LONGEST (for now). Not sure
2314 whether we want this to be true eventually. */
2315 return extract_typed_address (valaddr
, type
);
2318 error (_("Value can't be converted to integer."));
2320 return 0; /* Placate lint. */
2323 /* Return a double value from the specified type and address.
2324 INVP points to an int which is set to 0 for valid value,
2325 1 for invalid value (bad float format). In either case,
2326 the returned double is OK to use. Argument is in target
2327 format, result is in host format. */
2330 unpack_double (struct type
*type
, const gdb_byte
*valaddr
, int *invp
)
2332 enum bfd_endian byte_order
= gdbarch_byte_order (get_type_arch (type
));
2333 enum type_code code
;
2337 *invp
= 0; /* Assume valid. */
2338 CHECK_TYPEDEF (type
);
2339 code
= TYPE_CODE (type
);
2340 len
= TYPE_LENGTH (type
);
2341 nosign
= TYPE_UNSIGNED (type
);
2342 if (code
== TYPE_CODE_FLT
)
2344 /* NOTE: cagney/2002-02-19: There was a test here to see if the
2345 floating-point value was valid (using the macro
2346 INVALID_FLOAT). That test/macro have been removed.
2348 It turns out that only the VAX defined this macro and then
2349 only in a non-portable way. Fixing the portability problem
2350 wouldn't help since the VAX floating-point code is also badly
2351 bit-rotten. The target needs to add definitions for the
2352 methods gdbarch_float_format and gdbarch_double_format - these
2353 exactly describe the target floating-point format. The
2354 problem here is that the corresponding floatformat_vax_f and
2355 floatformat_vax_d values these methods should be set to are
2356 also not defined either. Oops!
2358 Hopefully someone will add both the missing floatformat
2359 definitions and the new cases for floatformat_is_valid (). */
2361 if (!floatformat_is_valid (floatformat_from_type (type
), valaddr
))
2367 return extract_typed_floating (valaddr
, type
);
2369 else if (code
== TYPE_CODE_DECFLOAT
)
2370 return decimal_to_doublest (valaddr
, len
, byte_order
);
2373 /* Unsigned -- be sure we compensate for signed LONGEST. */
2374 return (ULONGEST
) unpack_long (type
, valaddr
);
2378 /* Signed -- we are OK with unpack_long. */
2379 return unpack_long (type
, valaddr
);
2383 /* Unpack raw data (copied from debugee, target byte order) at VALADDR
2384 as a CORE_ADDR, assuming the raw data is described by type TYPE.
2385 We don't assume any alignment for the raw data. Return value is in
2388 If you want functions and arrays to be coerced to pointers, and
2389 references to be dereferenced, call value_as_address() instead.
2391 C++: It is assumed that the front-end has taken care of
2392 all matters concerning pointers to members. A pointer
2393 to member which reaches here is considered to be equivalent
2394 to an INT (or some size). After all, it is only an offset. */
2397 unpack_pointer (struct type
*type
, const gdb_byte
*valaddr
)
2399 /* Assume a CORE_ADDR can fit in a LONGEST (for now). Not sure
2400 whether we want this to be true eventually. */
2401 return unpack_long (type
, valaddr
);
2405 /* Get the value of the FIELDNO'th field (which must be static) of
2406 TYPE. Return NULL if the field doesn't exist or has been
2410 value_static_field (struct type
*type
, int fieldno
)
2412 struct value
*retval
;
2414 switch (TYPE_FIELD_LOC_KIND (type
, fieldno
))
2416 case FIELD_LOC_KIND_PHYSADDR
:
2417 retval
= value_at_lazy (TYPE_FIELD_TYPE (type
, fieldno
),
2418 TYPE_FIELD_STATIC_PHYSADDR (type
, fieldno
));
2420 case FIELD_LOC_KIND_PHYSNAME
:
2422 const char *phys_name
= TYPE_FIELD_STATIC_PHYSNAME (type
, fieldno
);
2423 /* TYPE_FIELD_NAME (type, fieldno); */
2424 struct symbol
*sym
= lookup_symbol (phys_name
, 0, VAR_DOMAIN
, 0);
2428 /* With some compilers, e.g. HP aCC, static data members are
2429 reported as non-debuggable symbols. */
2430 struct minimal_symbol
*msym
= lookup_minimal_symbol (phys_name
,
2437 retval
= value_at_lazy (TYPE_FIELD_TYPE (type
, fieldno
),
2438 SYMBOL_VALUE_ADDRESS (msym
));
2442 retval
= value_of_variable (sym
, NULL
);
2446 gdb_assert_not_reached ("unexpected field location kind");
2452 /* Change the enclosing type of a value object VAL to NEW_ENCL_TYPE.
2453 You have to be careful here, since the size of the data area for the value
2454 is set by the length of the enclosing type. So if NEW_ENCL_TYPE is bigger
2455 than the old enclosing type, you have to allocate more space for the
2459 set_value_enclosing_type (struct value
*val
, struct type
*new_encl_type
)
2461 if (TYPE_LENGTH (new_encl_type
) > TYPE_LENGTH (value_enclosing_type (val
)))
2463 (gdb_byte
*) xrealloc (val
->contents
, TYPE_LENGTH (new_encl_type
));
2465 val
->enclosing_type
= new_encl_type
;
2468 /* Given a value ARG1 (offset by OFFSET bytes)
2469 of a struct or union type ARG_TYPE,
2470 extract and return the value of one of its (non-static) fields.
2471 FIELDNO says which field. */
2474 value_primitive_field (struct value
*arg1
, int offset
,
2475 int fieldno
, struct type
*arg_type
)
2480 CHECK_TYPEDEF (arg_type
);
2481 type
= TYPE_FIELD_TYPE (arg_type
, fieldno
);
2483 /* Call check_typedef on our type to make sure that, if TYPE
2484 is a TYPE_CODE_TYPEDEF, its length is set to the length
2485 of the target type instead of zero. However, we do not
2486 replace the typedef type by the target type, because we want
2487 to keep the typedef in order to be able to print the type
2488 description correctly. */
2489 check_typedef (type
);
2491 if (value_optimized_out (arg1
))
2492 v
= allocate_optimized_out_value (type
);
2493 else if (TYPE_FIELD_BITSIZE (arg_type
, fieldno
))
2495 /* Handle packed fields.
2497 Create a new value for the bitfield, with bitpos and bitsize
2498 set. If possible, arrange offset and bitpos so that we can
2499 do a single aligned read of the size of the containing type.
2500 Otherwise, adjust offset to the byte containing the first
2501 bit. Assume that the address, offset, and embedded offset
2502 are sufficiently aligned. */
2504 int bitpos
= TYPE_FIELD_BITPOS (arg_type
, fieldno
);
2505 int container_bitsize
= TYPE_LENGTH (type
) * 8;
2507 v
= allocate_value_lazy (type
);
2508 v
->bitsize
= TYPE_FIELD_BITSIZE (arg_type
, fieldno
);
2509 if ((bitpos
% container_bitsize
) + v
->bitsize
<= container_bitsize
2510 && TYPE_LENGTH (type
) <= (int) sizeof (LONGEST
))
2511 v
->bitpos
= bitpos
% container_bitsize
;
2513 v
->bitpos
= bitpos
% 8;
2514 v
->offset
= (value_embedded_offset (arg1
)
2516 + (bitpos
- v
->bitpos
) / 8);
2518 value_incref (v
->parent
);
2519 if (!value_lazy (arg1
))
2520 value_fetch_lazy (v
);
2522 else if (fieldno
< TYPE_N_BASECLASSES (arg_type
))
2524 /* This field is actually a base subobject, so preserve the
2525 entire object's contents for later references to virtual
2528 /* Lazy register values with offsets are not supported. */
2529 if (VALUE_LVAL (arg1
) == lval_register
&& value_lazy (arg1
))
2530 value_fetch_lazy (arg1
);
2532 if (value_lazy (arg1
))
2533 v
= allocate_value_lazy (value_enclosing_type (arg1
));
2536 v
= allocate_value (value_enclosing_type (arg1
));
2537 value_contents_copy_raw (v
, 0, arg1
, 0,
2538 TYPE_LENGTH (value_enclosing_type (arg1
)));
2541 v
->offset
= value_offset (arg1
);
2542 v
->embedded_offset
= (offset
+ value_embedded_offset (arg1
)
2543 + TYPE_FIELD_BITPOS (arg_type
, fieldno
) / 8);
2547 /* Plain old data member */
2548 offset
+= TYPE_FIELD_BITPOS (arg_type
, fieldno
) / 8;
2550 /* Lazy register values with offsets are not supported. */
2551 if (VALUE_LVAL (arg1
) == lval_register
&& value_lazy (arg1
))
2552 value_fetch_lazy (arg1
);
2554 if (value_lazy (arg1
))
2555 v
= allocate_value_lazy (type
);
2558 v
= allocate_value (type
);
2559 value_contents_copy_raw (v
, value_embedded_offset (v
),
2560 arg1
, value_embedded_offset (arg1
) + offset
,
2561 TYPE_LENGTH (type
));
2563 v
->offset
= (value_offset (arg1
) + offset
2564 + value_embedded_offset (arg1
));
2566 set_value_component_location (v
, arg1
);
2567 VALUE_REGNUM (v
) = VALUE_REGNUM (arg1
);
2568 VALUE_FRAME_ID (v
) = VALUE_FRAME_ID (arg1
);
2572 /* Given a value ARG1 of a struct or union type,
2573 extract and return the value of one of its (non-static) fields.
2574 FIELDNO says which field. */
2577 value_field (struct value
*arg1
, int fieldno
)
2579 return value_primitive_field (arg1
, 0, fieldno
, value_type (arg1
));
2582 /* Return a non-virtual function as a value.
2583 F is the list of member functions which contains the desired method.
2584 J is an index into F which provides the desired method.
2586 We only use the symbol for its address, so be happy with either a
2587 full symbol or a minimal symbol. */
2590 value_fn_field (struct value
**arg1p
, struct fn_field
*f
,
2591 int j
, struct type
*type
,
2595 struct type
*ftype
= TYPE_FN_FIELD_TYPE (f
, j
);
2596 const char *physname
= TYPE_FN_FIELD_PHYSNAME (f
, j
);
2598 struct minimal_symbol
*msym
;
2600 sym
= lookup_symbol (physname
, 0, VAR_DOMAIN
, 0);
2607 gdb_assert (sym
== NULL
);
2608 msym
= lookup_minimal_symbol (physname
, NULL
, NULL
);
2613 v
= allocate_value (ftype
);
2616 set_value_address (v
, BLOCK_START (SYMBOL_BLOCK_VALUE (sym
)));
2620 /* The minimal symbol might point to a function descriptor;
2621 resolve it to the actual code address instead. */
2622 struct objfile
*objfile
= msymbol_objfile (msym
);
2623 struct gdbarch
*gdbarch
= get_objfile_arch (objfile
);
2625 set_value_address (v
,
2626 gdbarch_convert_from_func_ptr_addr
2627 (gdbarch
, SYMBOL_VALUE_ADDRESS (msym
), ¤t_target
));
2632 if (type
!= value_type (*arg1p
))
2633 *arg1p
= value_ind (value_cast (lookup_pointer_type (type
),
2634 value_addr (*arg1p
)));
2636 /* Move the `this' pointer according to the offset.
2637 VALUE_OFFSET (*arg1p) += offset; */
2645 /* Helper function for both unpack_value_bits_as_long and
2646 unpack_bits_as_long. See those functions for more details on the
2647 interface; the only difference is that this function accepts either
2648 a NULL or a non-NULL ORIGINAL_VALUE. */
2651 unpack_value_bits_as_long_1 (struct type
*field_type
, const gdb_byte
*valaddr
,
2652 int embedded_offset
, int bitpos
, int bitsize
,
2653 const struct value
*original_value
,
2656 enum bfd_endian byte_order
= gdbarch_byte_order (get_type_arch (field_type
));
2663 /* Read the minimum number of bytes required; there may not be
2664 enough bytes to read an entire ULONGEST. */
2665 CHECK_TYPEDEF (field_type
);
2667 bytes_read
= ((bitpos
% 8) + bitsize
+ 7) / 8;
2669 bytes_read
= TYPE_LENGTH (field_type
);
2671 read_offset
= bitpos
/ 8;
2673 if (original_value
!= NULL
2674 && !value_bytes_available (original_value
, embedded_offset
+ read_offset
,
2678 val
= extract_unsigned_integer (valaddr
+ embedded_offset
+ read_offset
,
2679 bytes_read
, byte_order
);
2681 /* Extract bits. See comment above. */
2683 if (gdbarch_bits_big_endian (get_type_arch (field_type
)))
2684 lsbcount
= (bytes_read
* 8 - bitpos
% 8 - bitsize
);
2686 lsbcount
= (bitpos
% 8);
2689 /* If the field does not entirely fill a LONGEST, then zero the sign bits.
2690 If the field is signed, and is negative, then sign extend. */
2692 if ((bitsize
> 0) && (bitsize
< 8 * (int) sizeof (val
)))
2694 valmask
= (((ULONGEST
) 1) << bitsize
) - 1;
2696 if (!TYPE_UNSIGNED (field_type
))
2698 if (val
& (valmask
^ (valmask
>> 1)))
2709 /* Unpack a bitfield of the specified FIELD_TYPE, from the object at
2710 VALADDR + EMBEDDED_OFFSET, and store the result in *RESULT.
2711 VALADDR points to the contents of ORIGINAL_VALUE, which must not be
2712 NULL. The bitfield starts at BITPOS bits and contains BITSIZE
2715 Returns false if the value contents are unavailable, otherwise
2716 returns true, indicating a valid value has been stored in *RESULT.
2718 Extracting bits depends on endianness of the machine. Compute the
2719 number of least significant bits to discard. For big endian machines,
2720 we compute the total number of bits in the anonymous object, subtract
2721 off the bit count from the MSB of the object to the MSB of the
2722 bitfield, then the size of the bitfield, which leaves the LSB discard
2723 count. For little endian machines, the discard count is simply the
2724 number of bits from the LSB of the anonymous object to the LSB of the
2727 If the field is signed, we also do sign extension. */
2730 unpack_value_bits_as_long (struct type
*field_type
, const gdb_byte
*valaddr
,
2731 int embedded_offset
, int bitpos
, int bitsize
,
2732 const struct value
*original_value
,
2735 gdb_assert (original_value
!= NULL
);
2737 return unpack_value_bits_as_long_1 (field_type
, valaddr
, embedded_offset
,
2738 bitpos
, bitsize
, original_value
, result
);
2742 /* Unpack a field FIELDNO of the specified TYPE, from the object at
2743 VALADDR + EMBEDDED_OFFSET. VALADDR points to the contents of
2744 ORIGINAL_VALUE. See unpack_value_bits_as_long for more
2748 unpack_value_field_as_long_1 (struct type
*type
, const gdb_byte
*valaddr
,
2749 int embedded_offset
, int fieldno
,
2750 const struct value
*val
, LONGEST
*result
)
2752 int bitpos
= TYPE_FIELD_BITPOS (type
, fieldno
);
2753 int bitsize
= TYPE_FIELD_BITSIZE (type
, fieldno
);
2754 struct type
*field_type
= TYPE_FIELD_TYPE (type
, fieldno
);
2756 return unpack_value_bits_as_long_1 (field_type
, valaddr
, embedded_offset
,
2757 bitpos
, bitsize
, val
,
2761 /* Unpack a field FIELDNO of the specified TYPE, from the object at
2762 VALADDR + EMBEDDED_OFFSET. VALADDR points to the contents of
2763 ORIGINAL_VALUE, which must not be NULL. See
2764 unpack_value_bits_as_long for more details. */
2767 unpack_value_field_as_long (struct type
*type
, const gdb_byte
*valaddr
,
2768 int embedded_offset
, int fieldno
,
2769 const struct value
*val
, LONGEST
*result
)
2771 gdb_assert (val
!= NULL
);
2773 return unpack_value_field_as_long_1 (type
, valaddr
, embedded_offset
,
2774 fieldno
, val
, result
);
2777 /* Unpack a field FIELDNO of the specified TYPE, from the anonymous
2778 object at VALADDR. See unpack_value_bits_as_long for more details.
2779 This function differs from unpack_value_field_as_long in that it
2780 operates without a struct value object. */
2783 unpack_field_as_long (struct type
*type
, const gdb_byte
*valaddr
, int fieldno
)
2787 unpack_value_field_as_long_1 (type
, valaddr
, 0, fieldno
, NULL
, &result
);
2791 /* Return a new value with type TYPE, which is FIELDNO field of the
2792 object at VALADDR + EMBEDDEDOFFSET. VALADDR points to the contents
2793 of VAL. If the VAL's contents required to extract the bitfield
2794 from are unavailable, the new value is correspondingly marked as
2798 value_field_bitfield (struct type
*type
, int fieldno
,
2799 const gdb_byte
*valaddr
,
2800 int embedded_offset
, const struct value
*val
)
2804 if (!unpack_value_field_as_long (type
, valaddr
, embedded_offset
, fieldno
,
2807 struct type
*field_type
= TYPE_FIELD_TYPE (type
, fieldno
);
2808 struct value
*retval
= allocate_value (field_type
);
2809 mark_value_bytes_unavailable (retval
, 0, TYPE_LENGTH (field_type
));
2814 return value_from_longest (TYPE_FIELD_TYPE (type
, fieldno
), l
);
2818 /* Modify the value of a bitfield. ADDR points to a block of memory in
2819 target byte order; the bitfield starts in the byte pointed to. FIELDVAL
2820 is the desired value of the field, in host byte order. BITPOS and BITSIZE
2821 indicate which bits (in target bit order) comprise the bitfield.
2822 Requires 0 < BITSIZE <= lbits, 0 <= BITPOS % 8 + BITSIZE <= lbits, and
2823 0 <= BITPOS, where lbits is the size of a LONGEST in bits. */
2826 modify_field (struct type
*type
, gdb_byte
*addr
,
2827 LONGEST fieldval
, int bitpos
, int bitsize
)
2829 enum bfd_endian byte_order
= gdbarch_byte_order (get_type_arch (type
));
2831 ULONGEST mask
= (ULONGEST
) -1 >> (8 * sizeof (ULONGEST
) - bitsize
);
2834 /* Normalize BITPOS. */
2838 /* If a negative fieldval fits in the field in question, chop
2839 off the sign extension bits. */
2840 if ((~fieldval
& ~(mask
>> 1)) == 0)
2843 /* Warn if value is too big to fit in the field in question. */
2844 if (0 != (fieldval
& ~mask
))
2846 /* FIXME: would like to include fieldval in the message, but
2847 we don't have a sprintf_longest. */
2848 warning (_("Value does not fit in %d bits."), bitsize
);
2850 /* Truncate it, otherwise adjoining fields may be corrupted. */
2854 /* Ensure no bytes outside of the modified ones get accessed as it may cause
2855 false valgrind reports. */
2857 bytesize
= (bitpos
+ bitsize
+ 7) / 8;
2858 oword
= extract_unsigned_integer (addr
, bytesize
, byte_order
);
2860 /* Shifting for bit field depends on endianness of the target machine. */
2861 if (gdbarch_bits_big_endian (get_type_arch (type
)))
2862 bitpos
= bytesize
* 8 - bitpos
- bitsize
;
2864 oword
&= ~(mask
<< bitpos
);
2865 oword
|= fieldval
<< bitpos
;
2867 store_unsigned_integer (addr
, bytesize
, byte_order
, oword
);
2870 /* Pack NUM into BUF using a target format of TYPE. */
2873 pack_long (gdb_byte
*buf
, struct type
*type
, LONGEST num
)
2875 enum bfd_endian byte_order
= gdbarch_byte_order (get_type_arch (type
));
2878 type
= check_typedef (type
);
2879 len
= TYPE_LENGTH (type
);
2881 switch (TYPE_CODE (type
))
2884 case TYPE_CODE_CHAR
:
2885 case TYPE_CODE_ENUM
:
2886 case TYPE_CODE_FLAGS
:
2887 case TYPE_CODE_BOOL
:
2888 case TYPE_CODE_RANGE
:
2889 case TYPE_CODE_MEMBERPTR
:
2890 store_signed_integer (buf
, len
, byte_order
, num
);
2895 store_typed_address (buf
, type
, (CORE_ADDR
) num
);
2899 error (_("Unexpected type (%d) encountered for integer constant."),
2905 /* Pack NUM into BUF using a target format of TYPE. */
2908 pack_unsigned_long (gdb_byte
*buf
, struct type
*type
, ULONGEST num
)
2911 enum bfd_endian byte_order
;
2913 type
= check_typedef (type
);
2914 len
= TYPE_LENGTH (type
);
2915 byte_order
= gdbarch_byte_order (get_type_arch (type
));
2917 switch (TYPE_CODE (type
))
2920 case TYPE_CODE_CHAR
:
2921 case TYPE_CODE_ENUM
:
2922 case TYPE_CODE_FLAGS
:
2923 case TYPE_CODE_BOOL
:
2924 case TYPE_CODE_RANGE
:
2925 case TYPE_CODE_MEMBERPTR
:
2926 store_unsigned_integer (buf
, len
, byte_order
, num
);
2931 store_typed_address (buf
, type
, (CORE_ADDR
) num
);
2935 error (_("Unexpected type (%d) encountered "
2936 "for unsigned integer constant."),
2942 /* Convert C numbers into newly allocated values. */
2945 value_from_longest (struct type
*type
, LONGEST num
)
2947 struct value
*val
= allocate_value (type
);
2949 pack_long (value_contents_raw (val
), type
, num
);
2954 /* Convert C unsigned numbers into newly allocated values. */
2957 value_from_ulongest (struct type
*type
, ULONGEST num
)
2959 struct value
*val
= allocate_value (type
);
2961 pack_unsigned_long (value_contents_raw (val
), type
, num
);
2967 /* Create a value representing a pointer of type TYPE to the address
2970 value_from_pointer (struct type
*type
, CORE_ADDR addr
)
2972 struct value
*val
= allocate_value (type
);
2974 store_typed_address (value_contents_raw (val
), check_typedef (type
), addr
);
2979 /* Create a value of type TYPE whose contents come from VALADDR, if it
2980 is non-null, and whose memory address (in the inferior) is
2984 value_from_contents_and_address (struct type
*type
,
2985 const gdb_byte
*valaddr
,
2990 if (valaddr
== NULL
)
2991 v
= allocate_value_lazy (type
);
2994 v
= allocate_value (type
);
2995 memcpy (value_contents_raw (v
), valaddr
, TYPE_LENGTH (type
));
2997 set_value_address (v
, address
);
2998 VALUE_LVAL (v
) = lval_memory
;
3002 /* Create a value of type TYPE holding the contents CONTENTS.
3003 The new value is `not_lval'. */
3006 value_from_contents (struct type
*type
, const gdb_byte
*contents
)
3008 struct value
*result
;
3010 result
= allocate_value (type
);
3011 memcpy (value_contents_raw (result
), contents
, TYPE_LENGTH (type
));
3016 value_from_double (struct type
*type
, DOUBLEST num
)
3018 struct value
*val
= allocate_value (type
);
3019 struct type
*base_type
= check_typedef (type
);
3020 enum type_code code
= TYPE_CODE (base_type
);
3022 if (code
== TYPE_CODE_FLT
)
3024 store_typed_floating (value_contents_raw (val
), base_type
, num
);
3027 error (_("Unexpected type encountered for floating constant."));
3033 value_from_decfloat (struct type
*type
, const gdb_byte
*dec
)
3035 struct value
*val
= allocate_value (type
);
3037 memcpy (value_contents_raw (val
), dec
, TYPE_LENGTH (type
));
3041 /* Extract a value from the history file. Input will be of the form
3042 $digits or $$digits. See block comment above 'write_dollar_variable'
3046 value_from_history_ref (char *h
, char **endp
)
3058 /* Find length of numeral string. */
3059 for (; isdigit (h
[len
]); len
++)
3062 /* Make sure numeral string is not part of an identifier. */
3063 if (h
[len
] == '_' || isalpha (h
[len
]))
3066 /* Now collect the index value. */
3071 /* For some bizarre reason, "$$" is equivalent to "$$1",
3072 rather than to "$$0" as it ought to be! */
3077 index
= -strtol (&h
[2], endp
, 10);
3083 /* "$" is equivalent to "$0". */
3088 index
= strtol (&h
[1], endp
, 10);
3091 return access_value_history (index
);
3095 coerce_ref_if_computed (const struct value
*arg
)
3097 const struct lval_funcs
*funcs
;
3099 if (TYPE_CODE (check_typedef (value_type (arg
))) != TYPE_CODE_REF
)
3102 if (value_lval_const (arg
) != lval_computed
)
3105 funcs
= value_computed_funcs (arg
);
3106 if (funcs
->coerce_ref
== NULL
)
3109 return funcs
->coerce_ref (arg
);
3113 coerce_ref (struct value
*arg
)
3115 struct type
*value_type_arg_tmp
= check_typedef (value_type (arg
));
3116 struct value
*retval
;
3118 retval
= coerce_ref_if_computed (arg
);
3122 if (TYPE_CODE (value_type_arg_tmp
) != TYPE_CODE_REF
)
3125 return value_at_lazy (TYPE_TARGET_TYPE (value_type_arg_tmp
),
3126 unpack_pointer (value_type (arg
),
3127 value_contents (arg
)));
3131 coerce_array (struct value
*arg
)
3135 arg
= coerce_ref (arg
);
3136 type
= check_typedef (value_type (arg
));
3138 switch (TYPE_CODE (type
))
3140 case TYPE_CODE_ARRAY
:
3141 if (!TYPE_VECTOR (type
) && current_language
->c_style_arrays
)
3142 arg
= value_coerce_array (arg
);
3144 case TYPE_CODE_FUNC
:
3145 arg
= value_coerce_function (arg
);
3152 /* Return true if the function returning the specified type is using
3153 the convention of returning structures in memory (passing in the
3154 address as a hidden first parameter). */
3157 using_struct_return (struct gdbarch
*gdbarch
,
3158 struct type
*func_type
, struct type
*value_type
)
3160 enum type_code code
= TYPE_CODE (value_type
);
3162 if (code
== TYPE_CODE_ERROR
)
3163 error (_("Function return type unknown."));
3165 if (code
== TYPE_CODE_VOID
)
3166 /* A void return value is never in memory. See also corresponding
3167 code in "print_return_value". */
3170 /* Probe the architecture for the return-value convention. */
3171 return (gdbarch_return_value (gdbarch
, func_type
, value_type
,
3173 != RETURN_VALUE_REGISTER_CONVENTION
);
3176 /* Set the initialized field in a value struct. */
3179 set_value_initialized (struct value
*val
, int status
)
3181 val
->initialized
= status
;
3184 /* Return the initialized field in a value struct. */
3187 value_initialized (struct value
*val
)
3189 return val
->initialized
;
3193 _initialize_values (void)
3195 add_cmd ("convenience", no_class
, show_convenience
, _("\
3196 Debugger convenience (\"$foo\") variables.\n\
3197 These variables are created when you assign them values;\n\
3198 thus, \"print $foo=1\" gives \"$foo\" the value 1. Values may be any type.\n\
3200 A few convenience variables are given values automatically:\n\
3201 \"$_\"holds the last address examined with \"x\" or \"info lines\",\n\
3202 \"$__\" holds the contents of the last address examined with \"x\"."),
3205 add_cmd ("values", no_set_class
, show_values
, _("\
3206 Elements of value history around item number IDX (or last ten)."),
3209 add_com ("init-if-undefined", class_vars
, init_if_undefined_command
, _("\
3210 Initialize a convenience variable if necessary.\n\
3211 init-if-undefined VARIABLE = EXPRESSION\n\
3212 Set an internal VARIABLE to the result of the EXPRESSION if it does not\n\
3213 exist or does not contain a value. The EXPRESSION is not evaluated if the\n\
3214 VARIABLE is already initialized."));
3216 add_prefix_cmd ("function", no_class
, function_command
, _("\
3217 Placeholder command for showing help on convenience functions."),
3218 &functionlist
, "function ", 0, &cmdlist
);