1 /* Low level packing and unpacking of values for GDB, the GNU Debugger.
3 Copyright (C) 1986-2014 Free Software Foundation, Inc.
5 This file is part of GDB.
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 3 of the License, or
10 (at your option) any later version.
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with this program. If not, see <http://www.gnu.org/licenses/>. */
21 #include "arch-utils.h"
37 #include "cli/cli-decode.h"
38 #include "exceptions.h"
39 #include "extension.h"
41 #include "tracepoint.h"
43 #include "user-regs.h"
45 /* Prototypes for exported functions. */
47 void _initialize_values (void);
49 /* Definition of a user function. */
50 struct internal_function
52 /* The name of the function. It is a bit odd to have this in the
53 function itself -- the user might use a differently-named
54 convenience variable to hold the function. */
58 internal_function_fn handler
;
60 /* User data for the handler. */
64 /* Defines an [OFFSET, OFFSET + LENGTH) range. */
68 /* Lowest offset in the range. */
71 /* Length of the range. */
75 typedef struct range range_s
;
79 /* Returns true if the ranges defined by [offset1, offset1+len1) and
80 [offset2, offset2+len2) overlap. */
83 ranges_overlap (int offset1
, int len1
,
84 int offset2
, int len2
)
88 l
= max (offset1
, offset2
);
89 h
= min (offset1
+ len1
, offset2
+ len2
);
93 /* Returns true if the first argument is strictly less than the
94 second, useful for VEC_lower_bound. We keep ranges sorted by
95 offset and coalesce overlapping and contiguous ranges, so this just
96 compares the starting offset. */
99 range_lessthan (const range_s
*r1
, const range_s
*r2
)
101 return r1
->offset
< r2
->offset
;
104 /* Returns true if RANGES contains any range that overlaps [OFFSET,
108 ranges_contain (VEC(range_s
) *ranges
, int offset
, int length
)
113 what
.offset
= offset
;
114 what
.length
= length
;
116 /* We keep ranges sorted by offset and coalesce overlapping and
117 contiguous ranges, so to check if a range list contains a given
118 range, we can do a binary search for the position the given range
119 would be inserted if we only considered the starting OFFSET of
120 ranges. We call that position I. Since we also have LENGTH to
121 care for (this is a range afterall), we need to check if the
122 _previous_ range overlaps the I range. E.g.,
126 |---| |---| |------| ... |--|
131 In the case above, the binary search would return `I=1', meaning,
132 this OFFSET should be inserted at position 1, and the current
133 position 1 should be pushed further (and before 2). But, `0'
136 Then we need to check if the I range overlaps the I range itself.
141 |---| |---| |-------| ... |--|
147 i
= VEC_lower_bound (range_s
, ranges
, &what
, range_lessthan
);
151 struct range
*bef
= VEC_index (range_s
, ranges
, i
- 1);
153 if (ranges_overlap (bef
->offset
, bef
->length
, offset
, length
))
157 if (i
< VEC_length (range_s
, ranges
))
159 struct range
*r
= VEC_index (range_s
, ranges
, i
);
161 if (ranges_overlap (r
->offset
, r
->length
, offset
, length
))
168 static struct cmd_list_element
*functionlist
;
170 /* Note that the fields in this structure are arranged to save a bit
175 /* Type of value; either not an lval, or one of the various
176 different possible kinds of lval. */
179 /* Is it modifiable? Only relevant if lval != not_lval. */
180 unsigned int modifiable
: 1;
182 /* If zero, contents of this value are in the contents field. If
183 nonzero, contents are in inferior. If the lval field is lval_memory,
184 the contents are in inferior memory at location.address plus offset.
185 The lval field may also be lval_register.
187 WARNING: This field is used by the code which handles watchpoints
188 (see breakpoint.c) to decide whether a particular value can be
189 watched by hardware watchpoints. If the lazy flag is set for
190 some member of a value chain, it is assumed that this member of
191 the chain doesn't need to be watched as part of watching the
192 value itself. This is how GDB avoids watching the entire struct
193 or array when the user wants to watch a single struct member or
194 array element. If you ever change the way lazy flag is set and
195 reset, be sure to consider this use as well! */
196 unsigned int lazy
: 1;
198 /* If value is a variable, is it initialized or not. */
199 unsigned int initialized
: 1;
201 /* If value is from the stack. If this is set, read_stack will be
202 used instead of read_memory to enable extra caching. */
203 unsigned int stack
: 1;
205 /* If the value has been released. */
206 unsigned int released
: 1;
208 /* Register number if the value is from a register. */
211 /* Location of value (if lval). */
214 /* If lval == lval_memory, this is the address in the inferior.
215 If lval == lval_register, this is the byte offset into the
216 registers structure. */
219 /* Pointer to internal variable. */
220 struct internalvar
*internalvar
;
222 /* Pointer to xmethod worker. */
223 struct xmethod_worker
*xm_worker
;
225 /* If lval == lval_computed, this is a set of function pointers
226 to use to access and describe the value, and a closure pointer
230 /* Functions to call. */
231 const struct lval_funcs
*funcs
;
233 /* Closure for those functions to use. */
238 /* Describes offset of a value within lval of a structure in bytes.
239 If lval == lval_memory, this is an offset to the address. If
240 lval == lval_register, this is a further offset from
241 location.address within the registers structure. Note also the
242 member embedded_offset below. */
245 /* Only used for bitfields; number of bits contained in them. */
248 /* Only used for bitfields; position of start of field. For
249 gdbarch_bits_big_endian=0 targets, it is the position of the LSB. For
250 gdbarch_bits_big_endian=1 targets, it is the position of the MSB. */
253 /* The number of references to this value. When a value is created,
254 the value chain holds a reference, so REFERENCE_COUNT is 1. If
255 release_value is called, this value is removed from the chain but
256 the caller of release_value now has a reference to this value.
257 The caller must arrange for a call to value_free later. */
260 /* Only used for bitfields; the containing value. This allows a
261 single read from the target when displaying multiple
263 struct value
*parent
;
265 /* Frame register value is relative to. This will be described in
266 the lval enum above as "lval_register". */
267 struct frame_id frame_id
;
269 /* Type of the value. */
272 /* If a value represents a C++ object, then the `type' field gives
273 the object's compile-time type. If the object actually belongs
274 to some class derived from `type', perhaps with other base
275 classes and additional members, then `type' is just a subobject
276 of the real thing, and the full object is probably larger than
277 `type' would suggest.
279 If `type' is a dynamic class (i.e. one with a vtable), then GDB
280 can actually determine the object's run-time type by looking at
281 the run-time type information in the vtable. When this
282 information is available, we may elect to read in the entire
283 object, for several reasons:
285 - When printing the value, the user would probably rather see the
286 full object, not just the limited portion apparent from the
289 - If `type' has virtual base classes, then even printing `type'
290 alone may require reaching outside the `type' portion of the
291 object to wherever the virtual base class has been stored.
293 When we store the entire object, `enclosing_type' is the run-time
294 type -- the complete object -- and `embedded_offset' is the
295 offset of `type' within that larger type, in bytes. The
296 value_contents() macro takes `embedded_offset' into account, so
297 most GDB code continues to see the `type' portion of the value,
298 just as the inferior would.
300 If `type' is a pointer to an object, then `enclosing_type' is a
301 pointer to the object's run-time type, and `pointed_to_offset' is
302 the offset in bytes from the full object to the pointed-to object
303 -- that is, the value `embedded_offset' would have if we followed
304 the pointer and fetched the complete object. (I don't really see
305 the point. Why not just determine the run-time type when you
306 indirect, and avoid the special case? The contents don't matter
307 until you indirect anyway.)
309 If we're not doing anything fancy, `enclosing_type' is equal to
310 `type', and `embedded_offset' is zero, so everything works
312 struct type
*enclosing_type
;
314 int pointed_to_offset
;
316 /* Values are stored in a chain, so that they can be deleted easily
317 over calls to the inferior. Values assigned to internal
318 variables, put into the value history or exposed to Python are
319 taken off this list. */
322 /* Actual contents of the value. Target byte-order. NULL or not
323 valid if lazy is nonzero. */
326 /* Unavailable ranges in CONTENTS. We mark unavailable ranges,
327 rather than available, since the common and default case is for a
328 value to be available. This is filled in at value read time.
329 The unavailable ranges are tracked in bits. Note that a contents
330 bit that has been optimized out doesn't really exist in the
331 program, so it can't be marked unavailable either. */
332 VEC(range_s
) *unavailable
;
334 /* Likewise, but for optimized out contents (a chunk of the value of
335 a variable that does not actually exist in the program). If LVAL
336 is lval_register, this is a register ($pc, $sp, etc., never a
337 program variable) that has not been saved in the frame. Not
338 saved registers and optimized-out program variables values are
339 treated pretty much the same, except not-saved registers have a
340 different string representation and related error strings. */
341 VEC(range_s
) *optimized_out
;
345 value_bits_available (const struct value
*value
, int offset
, int length
)
347 gdb_assert (!value
->lazy
);
349 return !ranges_contain (value
->unavailable
, offset
, length
);
353 value_bytes_available (const struct value
*value
, int offset
, int length
)
355 return value_bits_available (value
,
356 offset
* TARGET_CHAR_BIT
,
357 length
* TARGET_CHAR_BIT
);
361 value_bits_any_optimized_out (const struct value
*value
, int bit_offset
, int bit_length
)
363 gdb_assert (!value
->lazy
);
365 return ranges_contain (value
->optimized_out
, bit_offset
, bit_length
);
369 value_entirely_available (struct value
*value
)
371 /* We can only tell whether the whole value is available when we try
374 value_fetch_lazy (value
);
376 if (VEC_empty (range_s
, value
->unavailable
))
381 /* Returns true if VALUE is entirely covered by RANGES. If the value
382 is lazy, it'll be read now. Note that RANGE is a pointer to
383 pointer because reading the value might change *RANGE. */
386 value_entirely_covered_by_range_vector (struct value
*value
,
387 VEC(range_s
) **ranges
)
389 /* We can only tell whether the whole value is optimized out /
390 unavailable when we try to read it. */
392 value_fetch_lazy (value
);
394 if (VEC_length (range_s
, *ranges
) == 1)
396 struct range
*t
= VEC_index (range_s
, *ranges
, 0);
399 && t
->length
== (TARGET_CHAR_BIT
400 * TYPE_LENGTH (value_enclosing_type (value
))))
408 value_entirely_unavailable (struct value
*value
)
410 return value_entirely_covered_by_range_vector (value
, &value
->unavailable
);
414 value_entirely_optimized_out (struct value
*value
)
416 return value_entirely_covered_by_range_vector (value
, &value
->optimized_out
);
419 /* Insert into the vector pointed to by VECTORP the bit range starting of
420 OFFSET bits, and extending for the next LENGTH bits. */
423 insert_into_bit_range_vector (VEC(range_s
) **vectorp
, int offset
, int length
)
428 /* Insert the range sorted. If there's overlap or the new range
429 would be contiguous with an existing range, merge. */
431 newr
.offset
= offset
;
432 newr
.length
= length
;
434 /* Do a binary search for the position the given range would be
435 inserted if we only considered the starting OFFSET of ranges.
436 Call that position I. Since we also have LENGTH to care for
437 (this is a range afterall), we need to check if the _previous_
438 range overlaps the I range. E.g., calling R the new range:
440 #1 - overlaps with previous
444 |---| |---| |------| ... |--|
449 In the case #1 above, the binary search would return `I=1',
450 meaning, this OFFSET should be inserted at position 1, and the
451 current position 1 should be pushed further (and become 2). But,
452 note that `0' overlaps with R, so we want to merge them.
454 A similar consideration needs to be taken if the new range would
455 be contiguous with the previous range:
457 #2 - contiguous with previous
461 |--| |---| |------| ... |--|
466 If there's no overlap with the previous range, as in:
468 #3 - not overlapping and not contiguous
472 |--| |---| |------| ... |--|
479 #4 - R is the range with lowest offset
483 |--| |---| |------| ... |--|
488 ... we just push the new range to I.
490 All the 4 cases above need to consider that the new range may
491 also overlap several of the ranges that follow, or that R may be
492 contiguous with the following range, and merge. E.g.,
494 #5 - overlapping following ranges
497 |------------------------|
498 |--| |---| |------| ... |--|
507 |--| |---| |------| ... |--|
514 i
= VEC_lower_bound (range_s
, *vectorp
, &newr
, range_lessthan
);
517 struct range
*bef
= VEC_index (range_s
, *vectorp
, i
- 1);
519 if (ranges_overlap (bef
->offset
, bef
->length
, offset
, length
))
522 ULONGEST l
= min (bef
->offset
, offset
);
523 ULONGEST h
= max (bef
->offset
+ bef
->length
, offset
+ length
);
529 else if (offset
== bef
->offset
+ bef
->length
)
532 bef
->length
+= length
;
538 VEC_safe_insert (range_s
, *vectorp
, i
, &newr
);
544 VEC_safe_insert (range_s
, *vectorp
, i
, &newr
);
547 /* Check whether the ranges following the one we've just added or
548 touched can be folded in (#5 above). */
549 if (i
+ 1 < VEC_length (range_s
, *vectorp
))
556 /* Get the range we just touched. */
557 t
= VEC_index (range_s
, *vectorp
, i
);
561 for (; VEC_iterate (range_s
, *vectorp
, i
, r
); i
++)
562 if (r
->offset
<= t
->offset
+ t
->length
)
566 l
= min (t
->offset
, r
->offset
);
567 h
= max (t
->offset
+ t
->length
, r
->offset
+ r
->length
);
576 /* If we couldn't merge this one, we won't be able to
577 merge following ones either, since the ranges are
578 always sorted by OFFSET. */
583 VEC_block_remove (range_s
, *vectorp
, next
, removed
);
588 mark_value_bits_unavailable (struct value
*value
, int offset
, int length
)
590 insert_into_bit_range_vector (&value
->unavailable
, offset
, length
);
594 mark_value_bytes_unavailable (struct value
*value
, int offset
, int length
)
596 mark_value_bits_unavailable (value
,
597 offset
* TARGET_CHAR_BIT
,
598 length
* TARGET_CHAR_BIT
);
601 /* Find the first range in RANGES that overlaps the range defined by
602 OFFSET and LENGTH, starting at element POS in the RANGES vector,
603 Returns the index into RANGES where such overlapping range was
604 found, or -1 if none was found. */
607 find_first_range_overlap (VEC(range_s
) *ranges
, int pos
,
608 int offset
, int length
)
613 for (i
= pos
; VEC_iterate (range_s
, ranges
, i
, r
); i
++)
614 if (ranges_overlap (r
->offset
, r
->length
, offset
, length
))
620 /* Compare LENGTH_BITS of memory at PTR1 + OFFSET1_BITS with the memory at
621 PTR2 + OFFSET2_BITS. Return 0 if the memory is the same, otherwise
624 It must always be the case that:
625 OFFSET1_BITS % TARGET_CHAR_BIT == OFFSET2_BITS % TARGET_CHAR_BIT
627 It is assumed that memory can be accessed from:
628 PTR + (OFFSET_BITS / TARGET_CHAR_BIT)
630 PTR + ((OFFSET_BITS + LENGTH_BITS + TARGET_CHAR_BIT - 1)
631 / TARGET_CHAR_BIT) */
633 memcmp_with_bit_offsets (const gdb_byte
*ptr1
, size_t offset1_bits
,
634 const gdb_byte
*ptr2
, size_t offset2_bits
,
637 gdb_assert (offset1_bits
% TARGET_CHAR_BIT
638 == offset2_bits
% TARGET_CHAR_BIT
);
640 if (offset1_bits
% TARGET_CHAR_BIT
!= 0)
643 gdb_byte mask
, b1
, b2
;
645 /* The offset from the base pointers PTR1 and PTR2 is not a complete
646 number of bytes. A number of bits up to either the next exact
647 byte boundary, or LENGTH_BITS (which ever is sooner) will be
649 bits
= TARGET_CHAR_BIT
- offset1_bits
% TARGET_CHAR_BIT
;
650 gdb_assert (bits
< sizeof (mask
) * TARGET_CHAR_BIT
);
651 mask
= (1 << bits
) - 1;
653 if (length_bits
< bits
)
655 mask
&= ~(gdb_byte
) ((1 << (bits
- length_bits
)) - 1);
659 /* Now load the two bytes and mask off the bits we care about. */
660 b1
= *(ptr1
+ offset1_bits
/ TARGET_CHAR_BIT
) & mask
;
661 b2
= *(ptr2
+ offset2_bits
/ TARGET_CHAR_BIT
) & mask
;
666 /* Now update the length and offsets to take account of the bits
667 we've just compared. */
669 offset1_bits
+= bits
;
670 offset2_bits
+= bits
;
673 if (length_bits
% TARGET_CHAR_BIT
!= 0)
677 gdb_byte mask
, b1
, b2
;
679 /* The length is not an exact number of bytes. After the previous
680 IF.. block then the offsets are byte aligned, or the
681 length is zero (in which case this code is not reached). Compare
682 a number of bits at the end of the region, starting from an exact
684 bits
= length_bits
% TARGET_CHAR_BIT
;
685 o1
= offset1_bits
+ length_bits
- bits
;
686 o2
= offset2_bits
+ length_bits
- bits
;
688 gdb_assert (bits
< sizeof (mask
) * TARGET_CHAR_BIT
);
689 mask
= ((1 << bits
) - 1) << (TARGET_CHAR_BIT
- bits
);
691 gdb_assert (o1
% TARGET_CHAR_BIT
== 0);
692 gdb_assert (o2
% TARGET_CHAR_BIT
== 0);
694 b1
= *(ptr1
+ o1
/ TARGET_CHAR_BIT
) & mask
;
695 b2
= *(ptr2
+ o2
/ TARGET_CHAR_BIT
) & mask
;
705 /* We've now taken care of any stray "bits" at the start, or end of
706 the region to compare, the remainder can be covered with a simple
708 gdb_assert (offset1_bits
% TARGET_CHAR_BIT
== 0);
709 gdb_assert (offset2_bits
% TARGET_CHAR_BIT
== 0);
710 gdb_assert (length_bits
% TARGET_CHAR_BIT
== 0);
712 return memcmp (ptr1
+ offset1_bits
/ TARGET_CHAR_BIT
,
713 ptr2
+ offset2_bits
/ TARGET_CHAR_BIT
,
714 length_bits
/ TARGET_CHAR_BIT
);
717 /* Length is zero, regions match. */
721 /* Helper struct for find_first_range_overlap_and_match and
722 value_contents_bits_eq. Keep track of which slot of a given ranges
723 vector have we last looked at. */
725 struct ranges_and_idx
728 VEC(range_s
) *ranges
;
730 /* The range we've last found in RANGES. Given ranges are sorted,
731 we can start the next lookup here. */
735 /* Helper function for value_contents_bits_eq. Compare LENGTH bits of
736 RP1's ranges starting at OFFSET1 bits with LENGTH bits of RP2's
737 ranges starting at OFFSET2 bits. Return true if the ranges match
738 and fill in *L and *H with the overlapping window relative to
739 (both) OFFSET1 or OFFSET2. */
742 find_first_range_overlap_and_match (struct ranges_and_idx
*rp1
,
743 struct ranges_and_idx
*rp2
,
744 int offset1
, int offset2
,
745 int length
, ULONGEST
*l
, ULONGEST
*h
)
747 rp1
->idx
= find_first_range_overlap (rp1
->ranges
, rp1
->idx
,
749 rp2
->idx
= find_first_range_overlap (rp2
->ranges
, rp2
->idx
,
752 if (rp1
->idx
== -1 && rp2
->idx
== -1)
758 else if (rp1
->idx
== -1 || rp2
->idx
== -1)
766 r1
= VEC_index (range_s
, rp1
->ranges
, rp1
->idx
);
767 r2
= VEC_index (range_s
, rp2
->ranges
, rp2
->idx
);
769 /* Get the unavailable windows intersected by the incoming
770 ranges. The first and last ranges that overlap the argument
771 range may be wider than said incoming arguments ranges. */
772 l1
= max (offset1
, r1
->offset
);
773 h1
= min (offset1
+ length
, r1
->offset
+ r1
->length
);
775 l2
= max (offset2
, r2
->offset
);
776 h2
= min (offset2
+ length
, offset2
+ r2
->length
);
778 /* Make them relative to the respective start offsets, so we can
779 compare them for equality. */
786 /* Different ranges, no match. */
787 if (l1
!= l2
|| h1
!= h2
)
796 /* Helper function for value_contents_eq. The only difference is that
797 this function is bit rather than byte based.
799 Compare LENGTH bits of VAL1's contents starting at OFFSET1 bits
800 with LENGTH bits of VAL2's contents starting at OFFSET2 bits.
801 Return true if the available bits match. */
804 value_contents_bits_eq (const struct value
*val1
, int offset1
,
805 const struct value
*val2
, int offset2
,
808 /* Each array element corresponds to a ranges source (unavailable,
809 optimized out). '1' is for VAL1, '2' for VAL2. */
810 struct ranges_and_idx rp1
[2], rp2
[2];
812 /* See function description in value.h. */
813 gdb_assert (!val1
->lazy
&& !val2
->lazy
);
815 /* We shouldn't be trying to compare past the end of the values. */
816 gdb_assert (offset1
+ length
817 <= TYPE_LENGTH (val1
->enclosing_type
) * TARGET_CHAR_BIT
);
818 gdb_assert (offset2
+ length
819 <= TYPE_LENGTH (val2
->enclosing_type
) * TARGET_CHAR_BIT
);
821 memset (&rp1
, 0, sizeof (rp1
));
822 memset (&rp2
, 0, sizeof (rp2
));
823 rp1
[0].ranges
= val1
->unavailable
;
824 rp2
[0].ranges
= val2
->unavailable
;
825 rp1
[1].ranges
= val1
->optimized_out
;
826 rp2
[1].ranges
= val2
->optimized_out
;
833 for (i
= 0; i
< 2; i
++)
835 ULONGEST l_tmp
, h_tmp
;
837 /* The contents only match equal if the invalid/unavailable
838 contents ranges match as well. */
839 if (!find_first_range_overlap_and_match (&rp1
[i
], &rp2
[i
],
840 offset1
, offset2
, length
,
844 /* We're interested in the lowest/first range found. */
845 if (i
== 0 || l_tmp
< l
)
852 /* Compare the available/valid contents. */
853 if (memcmp_with_bit_offsets (val1
->contents
, offset1
,
854 val2
->contents
, offset2
, l
) != 0)
866 value_contents_eq (const struct value
*val1
, int offset1
,
867 const struct value
*val2
, int offset2
,
870 return value_contents_bits_eq (val1
, offset1
* TARGET_CHAR_BIT
,
871 val2
, offset2
* TARGET_CHAR_BIT
,
872 length
* TARGET_CHAR_BIT
);
875 /* Prototypes for local functions. */
877 static void show_values (char *, int);
879 static void show_convenience (char *, int);
882 /* The value-history records all the values printed
883 by print commands during this session. Each chunk
884 records 60 consecutive values. The first chunk on
885 the chain records the most recent values.
886 The total number of values is in value_history_count. */
888 #define VALUE_HISTORY_CHUNK 60
890 struct value_history_chunk
892 struct value_history_chunk
*next
;
893 struct value
*values
[VALUE_HISTORY_CHUNK
];
896 /* Chain of chunks now in use. */
898 static struct value_history_chunk
*value_history_chain
;
900 static int value_history_count
; /* Abs number of last entry stored. */
903 /* List of all value objects currently allocated
904 (except for those released by calls to release_value)
905 This is so they can be freed after each command. */
907 static struct value
*all_values
;
909 /* Allocate a lazy value for type TYPE. Its actual content is
910 "lazily" allocated too: the content field of the return value is
911 NULL; it will be allocated when it is fetched from the target. */
914 allocate_value_lazy (struct type
*type
)
918 /* Call check_typedef on our type to make sure that, if TYPE
919 is a TYPE_CODE_TYPEDEF, its length is set to the length
920 of the target type instead of zero. However, we do not
921 replace the typedef type by the target type, because we want
922 to keep the typedef in order to be able to set the VAL's type
923 description correctly. */
924 check_typedef (type
);
926 val
= (struct value
*) xzalloc (sizeof (struct value
));
927 val
->contents
= NULL
;
928 val
->next
= all_values
;
931 val
->enclosing_type
= type
;
932 VALUE_LVAL (val
) = not_lval
;
933 val
->location
.address
= 0;
934 VALUE_FRAME_ID (val
) = null_frame_id
;
938 VALUE_REGNUM (val
) = -1;
940 val
->embedded_offset
= 0;
941 val
->pointed_to_offset
= 0;
943 val
->initialized
= 1; /* Default to initialized. */
945 /* Values start out on the all_values chain. */
946 val
->reference_count
= 1;
951 /* Allocate the contents of VAL if it has not been allocated yet. */
954 allocate_value_contents (struct value
*val
)
957 val
->contents
= (gdb_byte
*) xzalloc (TYPE_LENGTH (val
->enclosing_type
));
960 /* Allocate a value and its contents for type TYPE. */
963 allocate_value (struct type
*type
)
965 struct value
*val
= allocate_value_lazy (type
);
967 allocate_value_contents (val
);
972 /* Allocate a value that has the correct length
973 for COUNT repetitions of type TYPE. */
976 allocate_repeat_value (struct type
*type
, int count
)
978 int low_bound
= current_language
->string_lower_bound
; /* ??? */
979 /* FIXME-type-allocation: need a way to free this type when we are
981 struct type
*array_type
982 = lookup_array_range_type (type
, low_bound
, count
+ low_bound
- 1);
984 return allocate_value (array_type
);
988 allocate_computed_value (struct type
*type
,
989 const struct lval_funcs
*funcs
,
992 struct value
*v
= allocate_value_lazy (type
);
994 VALUE_LVAL (v
) = lval_computed
;
995 v
->location
.computed
.funcs
= funcs
;
996 v
->location
.computed
.closure
= closure
;
1001 /* Allocate NOT_LVAL value for type TYPE being OPTIMIZED_OUT. */
1004 allocate_optimized_out_value (struct type
*type
)
1006 struct value
*retval
= allocate_value_lazy (type
);
1008 mark_value_bytes_optimized_out (retval
, 0, TYPE_LENGTH (type
));
1009 set_value_lazy (retval
, 0);
1013 /* Accessor methods. */
1016 value_next (struct value
*value
)
1022 value_type (const struct value
*value
)
1027 deprecated_set_value_type (struct value
*value
, struct type
*type
)
1033 value_offset (const struct value
*value
)
1035 return value
->offset
;
1038 set_value_offset (struct value
*value
, int offset
)
1040 value
->offset
= offset
;
1044 value_bitpos (const struct value
*value
)
1046 return value
->bitpos
;
1049 set_value_bitpos (struct value
*value
, int bit
)
1051 value
->bitpos
= bit
;
1055 value_bitsize (const struct value
*value
)
1057 return value
->bitsize
;
1060 set_value_bitsize (struct value
*value
, int bit
)
1062 value
->bitsize
= bit
;
1066 value_parent (struct value
*value
)
1068 return value
->parent
;
1074 set_value_parent (struct value
*value
, struct value
*parent
)
1076 struct value
*old
= value
->parent
;
1078 value
->parent
= parent
;
1080 value_incref (parent
);
1085 value_contents_raw (struct value
*value
)
1087 allocate_value_contents (value
);
1088 return value
->contents
+ value
->embedded_offset
;
1092 value_contents_all_raw (struct value
*value
)
1094 allocate_value_contents (value
);
1095 return value
->contents
;
1099 value_enclosing_type (struct value
*value
)
1101 return value
->enclosing_type
;
1104 /* Look at value.h for description. */
1107 value_actual_type (struct value
*value
, int resolve_simple_types
,
1108 int *real_type_found
)
1110 struct value_print_options opts
;
1111 struct type
*result
;
1113 get_user_print_options (&opts
);
1115 if (real_type_found
)
1116 *real_type_found
= 0;
1117 result
= value_type (value
);
1118 if (opts
.objectprint
)
1120 /* If result's target type is TYPE_CODE_STRUCT, proceed to
1121 fetch its rtti type. */
1122 if ((TYPE_CODE (result
) == TYPE_CODE_PTR
1123 || TYPE_CODE (result
) == TYPE_CODE_REF
)
1124 && TYPE_CODE (check_typedef (TYPE_TARGET_TYPE (result
)))
1125 == TYPE_CODE_STRUCT
)
1127 struct type
*real_type
;
1129 real_type
= value_rtti_indirect_type (value
, NULL
, NULL
, NULL
);
1132 if (real_type_found
)
1133 *real_type_found
= 1;
1137 else if (resolve_simple_types
)
1139 if (real_type_found
)
1140 *real_type_found
= 1;
1141 result
= value_enclosing_type (value
);
1149 error_value_optimized_out (void)
1151 error (_("value has been optimized out"));
1155 require_not_optimized_out (const struct value
*value
)
1157 if (!VEC_empty (range_s
, value
->optimized_out
))
1159 if (value
->lval
== lval_register
)
1160 error (_("register has not been saved in frame"));
1162 error_value_optimized_out ();
1167 require_available (const struct value
*value
)
1169 if (!VEC_empty (range_s
, value
->unavailable
))
1170 throw_error (NOT_AVAILABLE_ERROR
, _("value is not available"));
1174 value_contents_for_printing (struct value
*value
)
1177 value_fetch_lazy (value
);
1178 return value
->contents
;
1182 value_contents_for_printing_const (const struct value
*value
)
1184 gdb_assert (!value
->lazy
);
1185 return value
->contents
;
1189 value_contents_all (struct value
*value
)
1191 const gdb_byte
*result
= value_contents_for_printing (value
);
1192 require_not_optimized_out (value
);
1193 require_available (value
);
1197 /* Copy ranges in SRC_RANGE that overlap [SRC_BIT_OFFSET,
1198 SRC_BIT_OFFSET+BIT_LENGTH) ranges into *DST_RANGE, adjusted. */
1201 ranges_copy_adjusted (VEC (range_s
) **dst_range
, int dst_bit_offset
,
1202 VEC (range_s
) *src_range
, int src_bit_offset
,
1208 for (i
= 0; VEC_iterate (range_s
, src_range
, i
, r
); i
++)
1212 l
= max (r
->offset
, src_bit_offset
);
1213 h
= min (r
->offset
+ r
->length
, src_bit_offset
+ bit_length
);
1216 insert_into_bit_range_vector (dst_range
,
1217 dst_bit_offset
+ (l
- src_bit_offset
),
1222 /* Copy LENGTH bytes of SRC value's (all) contents
1223 (value_contents_all) starting at SRC_OFFSET, into DST value's (all)
1224 contents, starting at DST_OFFSET. If unavailable contents are
1225 being copied from SRC, the corresponding DST contents are marked
1226 unavailable accordingly. Neither DST nor SRC may be lazy
1229 It is assumed the contents of DST in the [DST_OFFSET,
1230 DST_OFFSET+LENGTH) range are wholly available. */
1233 value_contents_copy_raw (struct value
*dst
, int dst_offset
,
1234 struct value
*src
, int src_offset
, int length
)
1238 int src_bit_offset
, dst_bit_offset
, bit_length
;
1240 /* A lazy DST would make that this copy operation useless, since as
1241 soon as DST's contents were un-lazied (by a later value_contents
1242 call, say), the contents would be overwritten. A lazy SRC would
1243 mean we'd be copying garbage. */
1244 gdb_assert (!dst
->lazy
&& !src
->lazy
);
1246 /* The overwritten DST range gets unavailability ORed in, not
1247 replaced. Make sure to remember to implement replacing if it
1248 turns out actually necessary. */
1249 gdb_assert (value_bytes_available (dst
, dst_offset
, length
));
1250 gdb_assert (!value_bits_any_optimized_out (dst
,
1251 TARGET_CHAR_BIT
* dst_offset
,
1252 TARGET_CHAR_BIT
* length
));
1254 /* Copy the data. */
1255 memcpy (value_contents_all_raw (dst
) + dst_offset
,
1256 value_contents_all_raw (src
) + src_offset
,
1259 /* Copy the meta-data, adjusted. */
1260 src_bit_offset
= src_offset
* TARGET_CHAR_BIT
;
1261 dst_bit_offset
= dst_offset
* TARGET_CHAR_BIT
;
1262 bit_length
= length
* TARGET_CHAR_BIT
;
1264 ranges_copy_adjusted (&dst
->unavailable
, dst_bit_offset
,
1265 src
->unavailable
, src_bit_offset
,
1268 ranges_copy_adjusted (&dst
->optimized_out
, dst_bit_offset
,
1269 src
->optimized_out
, src_bit_offset
,
1273 /* Copy LENGTH bytes of SRC value's (all) contents
1274 (value_contents_all) starting at SRC_OFFSET byte, into DST value's
1275 (all) contents, starting at DST_OFFSET. If unavailable contents
1276 are being copied from SRC, the corresponding DST contents are
1277 marked unavailable accordingly. DST must not be lazy. If SRC is
1278 lazy, it will be fetched now.
1280 It is assumed the contents of DST in the [DST_OFFSET,
1281 DST_OFFSET+LENGTH) range are wholly available. */
1284 value_contents_copy (struct value
*dst
, int dst_offset
,
1285 struct value
*src
, int src_offset
, int length
)
1288 value_fetch_lazy (src
);
1290 value_contents_copy_raw (dst
, dst_offset
, src
, src_offset
, length
);
1294 value_lazy (struct value
*value
)
1300 set_value_lazy (struct value
*value
, int val
)
1306 value_stack (struct value
*value
)
1308 return value
->stack
;
1312 set_value_stack (struct value
*value
, int val
)
1318 value_contents (struct value
*value
)
1320 const gdb_byte
*result
= value_contents_writeable (value
);
1321 require_not_optimized_out (value
);
1322 require_available (value
);
1327 value_contents_writeable (struct value
*value
)
1330 value_fetch_lazy (value
);
1331 return value_contents_raw (value
);
1335 value_optimized_out (struct value
*value
)
1337 /* We can only know if a value is optimized out once we have tried to
1339 if (VEC_empty (range_s
, value
->optimized_out
) && value
->lazy
)
1340 value_fetch_lazy (value
);
1342 return !VEC_empty (range_s
, value
->optimized_out
);
1345 /* Mark contents of VALUE as optimized out, starting at OFFSET bytes, and
1346 the following LENGTH bytes. */
1349 mark_value_bytes_optimized_out (struct value
*value
, int offset
, int length
)
1351 mark_value_bits_optimized_out (value
,
1352 offset
* TARGET_CHAR_BIT
,
1353 length
* TARGET_CHAR_BIT
);
1359 mark_value_bits_optimized_out (struct value
*value
, int offset
, int length
)
1361 insert_into_bit_range_vector (&value
->optimized_out
, offset
, length
);
1365 value_bits_synthetic_pointer (const struct value
*value
,
1366 int offset
, int length
)
1368 if (value
->lval
!= lval_computed
1369 || !value
->location
.computed
.funcs
->check_synthetic_pointer
)
1371 return value
->location
.computed
.funcs
->check_synthetic_pointer (value
,
1377 value_embedded_offset (struct value
*value
)
1379 return value
->embedded_offset
;
1383 set_value_embedded_offset (struct value
*value
, int val
)
1385 value
->embedded_offset
= val
;
1389 value_pointed_to_offset (struct value
*value
)
1391 return value
->pointed_to_offset
;
1395 set_value_pointed_to_offset (struct value
*value
, int val
)
1397 value
->pointed_to_offset
= val
;
1400 const struct lval_funcs
*
1401 value_computed_funcs (const struct value
*v
)
1403 gdb_assert (value_lval_const (v
) == lval_computed
);
1405 return v
->location
.computed
.funcs
;
1409 value_computed_closure (const struct value
*v
)
1411 gdb_assert (v
->lval
== lval_computed
);
1413 return v
->location
.computed
.closure
;
1417 deprecated_value_lval_hack (struct value
*value
)
1419 return &value
->lval
;
1423 value_lval_const (const struct value
*value
)
1429 value_address (const struct value
*value
)
1431 if (value
->lval
== lval_internalvar
1432 || value
->lval
== lval_internalvar_component
1433 || value
->lval
== lval_xcallable
)
1435 if (value
->parent
!= NULL
)
1436 return value_address (value
->parent
) + value
->offset
;
1438 return value
->location
.address
+ value
->offset
;
1442 value_raw_address (struct value
*value
)
1444 if (value
->lval
== lval_internalvar
1445 || value
->lval
== lval_internalvar_component
1446 || value
->lval
== lval_xcallable
)
1448 return value
->location
.address
;
1452 set_value_address (struct value
*value
, CORE_ADDR addr
)
1454 gdb_assert (value
->lval
!= lval_internalvar
1455 && value
->lval
!= lval_internalvar_component
1456 && value
->lval
!= lval_xcallable
);
1457 value
->location
.address
= addr
;
1460 struct internalvar
**
1461 deprecated_value_internalvar_hack (struct value
*value
)
1463 return &value
->location
.internalvar
;
1467 deprecated_value_frame_id_hack (struct value
*value
)
1469 return &value
->frame_id
;
1473 deprecated_value_regnum_hack (struct value
*value
)
1475 return &value
->regnum
;
1479 deprecated_value_modifiable (struct value
*value
)
1481 return value
->modifiable
;
1484 /* Return a mark in the value chain. All values allocated after the
1485 mark is obtained (except for those released) are subject to being freed
1486 if a subsequent value_free_to_mark is passed the mark. */
1493 /* Take a reference to VAL. VAL will not be deallocated until all
1494 references are released. */
1497 value_incref (struct value
*val
)
1499 val
->reference_count
++;
1502 /* Release a reference to VAL, which was acquired with value_incref.
1503 This function is also called to deallocate values from the value
1507 value_free (struct value
*val
)
1511 gdb_assert (val
->reference_count
> 0);
1512 val
->reference_count
--;
1513 if (val
->reference_count
> 0)
1516 /* If there's an associated parent value, drop our reference to
1518 if (val
->parent
!= NULL
)
1519 value_free (val
->parent
);
1521 if (VALUE_LVAL (val
) == lval_computed
)
1523 const struct lval_funcs
*funcs
= val
->location
.computed
.funcs
;
1525 if (funcs
->free_closure
)
1526 funcs
->free_closure (val
);
1528 else if (VALUE_LVAL (val
) == lval_xcallable
)
1529 free_xmethod_worker (val
->location
.xm_worker
);
1531 xfree (val
->contents
);
1532 VEC_free (range_s
, val
->unavailable
);
1537 /* Free all values allocated since MARK was obtained by value_mark
1538 (except for those released). */
1540 value_free_to_mark (struct value
*mark
)
1545 for (val
= all_values
; val
&& val
!= mark
; val
= next
)
1554 /* Free all the values that have been allocated (except for those released).
1555 Call after each command, successful or not.
1556 In practice this is called before each command, which is sufficient. */
1559 free_all_values (void)
1564 for (val
= all_values
; val
; val
= next
)
1574 /* Frees all the elements in a chain of values. */
1577 free_value_chain (struct value
*v
)
1583 next
= value_next (v
);
1588 /* Remove VAL from the chain all_values
1589 so it will not be freed automatically. */
1592 release_value (struct value
*val
)
1596 if (all_values
== val
)
1598 all_values
= val
->next
;
1604 for (v
= all_values
; v
; v
= v
->next
)
1608 v
->next
= val
->next
;
1616 /* If the value is not already released, release it.
1617 If the value is already released, increment its reference count.
1618 That is, this function ensures that the value is released from the
1619 value chain and that the caller owns a reference to it. */
1622 release_value_or_incref (struct value
*val
)
1627 release_value (val
);
1630 /* Release all values up to mark */
1632 value_release_to_mark (struct value
*mark
)
1637 for (val
= next
= all_values
; next
; next
= next
->next
)
1639 if (next
->next
== mark
)
1641 all_values
= next
->next
;
1651 /* Return a copy of the value ARG.
1652 It contains the same contents, for same memory address,
1653 but it's a different block of storage. */
1656 value_copy (struct value
*arg
)
1658 struct type
*encl_type
= value_enclosing_type (arg
);
1661 if (value_lazy (arg
))
1662 val
= allocate_value_lazy (encl_type
);
1664 val
= allocate_value (encl_type
);
1665 val
->type
= arg
->type
;
1666 VALUE_LVAL (val
) = VALUE_LVAL (arg
);
1667 val
->location
= arg
->location
;
1668 val
->offset
= arg
->offset
;
1669 val
->bitpos
= arg
->bitpos
;
1670 val
->bitsize
= arg
->bitsize
;
1671 VALUE_FRAME_ID (val
) = VALUE_FRAME_ID (arg
);
1672 VALUE_REGNUM (val
) = VALUE_REGNUM (arg
);
1673 val
->lazy
= arg
->lazy
;
1674 val
->embedded_offset
= value_embedded_offset (arg
);
1675 val
->pointed_to_offset
= arg
->pointed_to_offset
;
1676 val
->modifiable
= arg
->modifiable
;
1677 if (!value_lazy (val
))
1679 memcpy (value_contents_all_raw (val
), value_contents_all_raw (arg
),
1680 TYPE_LENGTH (value_enclosing_type (arg
)));
1683 val
->unavailable
= VEC_copy (range_s
, arg
->unavailable
);
1684 val
->optimized_out
= VEC_copy (range_s
, arg
->optimized_out
);
1685 set_value_parent (val
, arg
->parent
);
1686 if (VALUE_LVAL (val
) == lval_computed
)
1688 const struct lval_funcs
*funcs
= val
->location
.computed
.funcs
;
1690 if (funcs
->copy_closure
)
1691 val
->location
.computed
.closure
= funcs
->copy_closure (val
);
1696 /* Return a version of ARG that is non-lvalue. */
1699 value_non_lval (struct value
*arg
)
1701 if (VALUE_LVAL (arg
) != not_lval
)
1703 struct type
*enc_type
= value_enclosing_type (arg
);
1704 struct value
*val
= allocate_value (enc_type
);
1706 memcpy (value_contents_all_raw (val
), value_contents_all (arg
),
1707 TYPE_LENGTH (enc_type
));
1708 val
->type
= arg
->type
;
1709 set_value_embedded_offset (val
, value_embedded_offset (arg
));
1710 set_value_pointed_to_offset (val
, value_pointed_to_offset (arg
));
1717 set_value_component_location (struct value
*component
,
1718 const struct value
*whole
)
1720 gdb_assert (whole
->lval
!= lval_xcallable
);
1722 if (whole
->lval
== lval_internalvar
)
1723 VALUE_LVAL (component
) = lval_internalvar_component
;
1725 VALUE_LVAL (component
) = whole
->lval
;
1727 component
->location
= whole
->location
;
1728 if (whole
->lval
== lval_computed
)
1730 const struct lval_funcs
*funcs
= whole
->location
.computed
.funcs
;
1732 if (funcs
->copy_closure
)
1733 component
->location
.computed
.closure
= funcs
->copy_closure (whole
);
1738 /* Access to the value history. */
1740 /* Record a new value in the value history.
1741 Returns the absolute history index of the entry. */
1744 record_latest_value (struct value
*val
)
1748 /* We don't want this value to have anything to do with the inferior anymore.
1749 In particular, "set $1 = 50" should not affect the variable from which
1750 the value was taken, and fast watchpoints should be able to assume that
1751 a value on the value history never changes. */
1752 if (value_lazy (val
))
1753 value_fetch_lazy (val
);
1754 /* We preserve VALUE_LVAL so that the user can find out where it was fetched
1755 from. This is a bit dubious, because then *&$1 does not just return $1
1756 but the current contents of that location. c'est la vie... */
1757 val
->modifiable
= 0;
1759 /* The value may have already been released, in which case we're adding a
1760 new reference for its entry in the history. That is why we call
1761 release_value_or_incref here instead of release_value. */
1762 release_value_or_incref (val
);
1764 /* Here we treat value_history_count as origin-zero
1765 and applying to the value being stored now. */
1767 i
= value_history_count
% VALUE_HISTORY_CHUNK
;
1770 struct value_history_chunk
*new
1771 = (struct value_history_chunk
*)
1773 xmalloc (sizeof (struct value_history_chunk
));
1774 memset (new->values
, 0, sizeof new->values
);
1775 new->next
= value_history_chain
;
1776 value_history_chain
= new;
1779 value_history_chain
->values
[i
] = val
;
1781 /* Now we regard value_history_count as origin-one
1782 and applying to the value just stored. */
1784 return ++value_history_count
;
1787 /* Return a copy of the value in the history with sequence number NUM. */
1790 access_value_history (int num
)
1792 struct value_history_chunk
*chunk
;
1797 absnum
+= value_history_count
;
1802 error (_("The history is empty."));
1804 error (_("There is only one value in the history."));
1806 error (_("History does not go back to $$%d."), -num
);
1808 if (absnum
> value_history_count
)
1809 error (_("History has not yet reached $%d."), absnum
);
1813 /* Now absnum is always absolute and origin zero. */
1815 chunk
= value_history_chain
;
1816 for (i
= (value_history_count
- 1) / VALUE_HISTORY_CHUNK
1817 - absnum
/ VALUE_HISTORY_CHUNK
;
1819 chunk
= chunk
->next
;
1821 return value_copy (chunk
->values
[absnum
% VALUE_HISTORY_CHUNK
]);
1825 show_values (char *num_exp
, int from_tty
)
1833 /* "show values +" should print from the stored position.
1834 "show values <exp>" should print around value number <exp>. */
1835 if (num_exp
[0] != '+' || num_exp
[1] != '\0')
1836 num
= parse_and_eval_long (num_exp
) - 5;
1840 /* "show values" means print the last 10 values. */
1841 num
= value_history_count
- 9;
1847 for (i
= num
; i
< num
+ 10 && i
<= value_history_count
; i
++)
1849 struct value_print_options opts
;
1851 val
= access_value_history (i
);
1852 printf_filtered (("$%d = "), i
);
1853 get_user_print_options (&opts
);
1854 value_print (val
, gdb_stdout
, &opts
);
1855 printf_filtered (("\n"));
1858 /* The next "show values +" should start after what we just printed. */
1861 /* Hitting just return after this command should do the same thing as
1862 "show values +". If num_exp is null, this is unnecessary, since
1863 "show values +" is not useful after "show values". */
1864 if (from_tty
&& num_exp
)
1871 /* Internal variables. These are variables within the debugger
1872 that hold values assigned by debugger commands.
1873 The user refers to them with a '$' prefix
1874 that does not appear in the variable names stored internally. */
1878 struct internalvar
*next
;
1881 /* We support various different kinds of content of an internal variable.
1882 enum internalvar_kind specifies the kind, and union internalvar_data
1883 provides the data associated with this particular kind. */
1885 enum internalvar_kind
1887 /* The internal variable is empty. */
1890 /* The value of the internal variable is provided directly as
1891 a GDB value object. */
1894 /* A fresh value is computed via a call-back routine on every
1895 access to the internal variable. */
1896 INTERNALVAR_MAKE_VALUE
,
1898 /* The internal variable holds a GDB internal convenience function. */
1899 INTERNALVAR_FUNCTION
,
1901 /* The variable holds an integer value. */
1902 INTERNALVAR_INTEGER
,
1904 /* The variable holds a GDB-provided string. */
1909 union internalvar_data
1911 /* A value object used with INTERNALVAR_VALUE. */
1912 struct value
*value
;
1914 /* The call-back routine used with INTERNALVAR_MAKE_VALUE. */
1917 /* The functions to call. */
1918 const struct internalvar_funcs
*functions
;
1920 /* The function's user-data. */
1924 /* The internal function used with INTERNALVAR_FUNCTION. */
1927 struct internal_function
*function
;
1928 /* True if this is the canonical name for the function. */
1932 /* An integer value used with INTERNALVAR_INTEGER. */
1935 /* If type is non-NULL, it will be used as the type to generate
1936 a value for this internal variable. If type is NULL, a default
1937 integer type for the architecture is used. */
1942 /* A string value used with INTERNALVAR_STRING. */
1947 static struct internalvar
*internalvars
;
1949 /* If the variable does not already exist create it and give it the
1950 value given. If no value is given then the default is zero. */
1952 init_if_undefined_command (char* args
, int from_tty
)
1954 struct internalvar
* intvar
;
1956 /* Parse the expression - this is taken from set_command(). */
1957 struct expression
*expr
= parse_expression (args
);
1958 register struct cleanup
*old_chain
=
1959 make_cleanup (free_current_contents
, &expr
);
1961 /* Validate the expression.
1962 Was the expression an assignment?
1963 Or even an expression at all? */
1964 if (expr
->nelts
== 0 || expr
->elts
[0].opcode
!= BINOP_ASSIGN
)
1965 error (_("Init-if-undefined requires an assignment expression."));
1967 /* Extract the variable from the parsed expression.
1968 In the case of an assign the lvalue will be in elts[1] and elts[2]. */
1969 if (expr
->elts
[1].opcode
!= OP_INTERNALVAR
)
1970 error (_("The first parameter to init-if-undefined "
1971 "should be a GDB variable."));
1972 intvar
= expr
->elts
[2].internalvar
;
1974 /* Only evaluate the expression if the lvalue is void.
1975 This may still fail if the expresssion is invalid. */
1976 if (intvar
->kind
== INTERNALVAR_VOID
)
1977 evaluate_expression (expr
);
1979 do_cleanups (old_chain
);
1983 /* Look up an internal variable with name NAME. NAME should not
1984 normally include a dollar sign.
1986 If the specified internal variable does not exist,
1987 the return value is NULL. */
1989 struct internalvar
*
1990 lookup_only_internalvar (const char *name
)
1992 struct internalvar
*var
;
1994 for (var
= internalvars
; var
; var
= var
->next
)
1995 if (strcmp (var
->name
, name
) == 0)
2001 /* Complete NAME by comparing it to the names of internal variables.
2002 Returns a vector of newly allocated strings, or NULL if no matches
2006 complete_internalvar (const char *name
)
2008 VEC (char_ptr
) *result
= NULL
;
2009 struct internalvar
*var
;
2012 len
= strlen (name
);
2014 for (var
= internalvars
; var
; var
= var
->next
)
2015 if (strncmp (var
->name
, name
, len
) == 0)
2017 char *r
= xstrdup (var
->name
);
2019 VEC_safe_push (char_ptr
, result
, r
);
2025 /* Create an internal variable with name NAME and with a void value.
2026 NAME should not normally include a dollar sign. */
2028 struct internalvar
*
2029 create_internalvar (const char *name
)
2031 struct internalvar
*var
;
2033 var
= (struct internalvar
*) xmalloc (sizeof (struct internalvar
));
2034 var
->name
= concat (name
, (char *)NULL
);
2035 var
->kind
= INTERNALVAR_VOID
;
2036 var
->next
= internalvars
;
2041 /* Create an internal variable with name NAME and register FUN as the
2042 function that value_of_internalvar uses to create a value whenever
2043 this variable is referenced. NAME should not normally include a
2044 dollar sign. DATA is passed uninterpreted to FUN when it is
2045 called. CLEANUP, if not NULL, is called when the internal variable
2046 is destroyed. It is passed DATA as its only argument. */
2048 struct internalvar
*
2049 create_internalvar_type_lazy (const char *name
,
2050 const struct internalvar_funcs
*funcs
,
2053 struct internalvar
*var
= create_internalvar (name
);
2055 var
->kind
= INTERNALVAR_MAKE_VALUE
;
2056 var
->u
.make_value
.functions
= funcs
;
2057 var
->u
.make_value
.data
= data
;
2061 /* See documentation in value.h. */
2064 compile_internalvar_to_ax (struct internalvar
*var
,
2065 struct agent_expr
*expr
,
2066 struct axs_value
*value
)
2068 if (var
->kind
!= INTERNALVAR_MAKE_VALUE
2069 || var
->u
.make_value
.functions
->compile_to_ax
== NULL
)
2072 var
->u
.make_value
.functions
->compile_to_ax (var
, expr
, value
,
2073 var
->u
.make_value
.data
);
2077 /* Look up an internal variable with name NAME. NAME should not
2078 normally include a dollar sign.
2080 If the specified internal variable does not exist,
2081 one is created, with a void value. */
2083 struct internalvar
*
2084 lookup_internalvar (const char *name
)
2086 struct internalvar
*var
;
2088 var
= lookup_only_internalvar (name
);
2092 return create_internalvar (name
);
2095 /* Return current value of internal variable VAR. For variables that
2096 are not inherently typed, use a value type appropriate for GDBARCH. */
2099 value_of_internalvar (struct gdbarch
*gdbarch
, struct internalvar
*var
)
2102 struct trace_state_variable
*tsv
;
2104 /* If there is a trace state variable of the same name, assume that
2105 is what we really want to see. */
2106 tsv
= find_trace_state_variable (var
->name
);
2109 tsv
->value_known
= target_get_trace_state_variable_value (tsv
->number
,
2111 if (tsv
->value_known
)
2112 val
= value_from_longest (builtin_type (gdbarch
)->builtin_int64
,
2115 val
= allocate_value (builtin_type (gdbarch
)->builtin_void
);
2121 case INTERNALVAR_VOID
:
2122 val
= allocate_value (builtin_type (gdbarch
)->builtin_void
);
2125 case INTERNALVAR_FUNCTION
:
2126 val
= allocate_value (builtin_type (gdbarch
)->internal_fn
);
2129 case INTERNALVAR_INTEGER
:
2130 if (!var
->u
.integer
.type
)
2131 val
= value_from_longest (builtin_type (gdbarch
)->builtin_int
,
2132 var
->u
.integer
.val
);
2134 val
= value_from_longest (var
->u
.integer
.type
, var
->u
.integer
.val
);
2137 case INTERNALVAR_STRING
:
2138 val
= value_cstring (var
->u
.string
, strlen (var
->u
.string
),
2139 builtin_type (gdbarch
)->builtin_char
);
2142 case INTERNALVAR_VALUE
:
2143 val
= value_copy (var
->u
.value
);
2144 if (value_lazy (val
))
2145 value_fetch_lazy (val
);
2148 case INTERNALVAR_MAKE_VALUE
:
2149 val
= (*var
->u
.make_value
.functions
->make_value
) (gdbarch
, var
,
2150 var
->u
.make_value
.data
);
2154 internal_error (__FILE__
, __LINE__
, _("bad kind"));
2157 /* Change the VALUE_LVAL to lval_internalvar so that future operations
2158 on this value go back to affect the original internal variable.
2160 Do not do this for INTERNALVAR_MAKE_VALUE variables, as those have
2161 no underlying modifyable state in the internal variable.
2163 Likewise, if the variable's value is a computed lvalue, we want
2164 references to it to produce another computed lvalue, where
2165 references and assignments actually operate through the
2166 computed value's functions.
2168 This means that internal variables with computed values
2169 behave a little differently from other internal variables:
2170 assignments to them don't just replace the previous value
2171 altogether. At the moment, this seems like the behavior we
2174 if (var
->kind
!= INTERNALVAR_MAKE_VALUE
2175 && val
->lval
!= lval_computed
)
2177 VALUE_LVAL (val
) = lval_internalvar
;
2178 VALUE_INTERNALVAR (val
) = var
;
2185 get_internalvar_integer (struct internalvar
*var
, LONGEST
*result
)
2187 if (var
->kind
== INTERNALVAR_INTEGER
)
2189 *result
= var
->u
.integer
.val
;
2193 if (var
->kind
== INTERNALVAR_VALUE
)
2195 struct type
*type
= check_typedef (value_type (var
->u
.value
));
2197 if (TYPE_CODE (type
) == TYPE_CODE_INT
)
2199 *result
= value_as_long (var
->u
.value
);
2208 get_internalvar_function (struct internalvar
*var
,
2209 struct internal_function
**result
)
2213 case INTERNALVAR_FUNCTION
:
2214 *result
= var
->u
.fn
.function
;
2223 set_internalvar_component (struct internalvar
*var
, int offset
, int bitpos
,
2224 int bitsize
, struct value
*newval
)
2230 case INTERNALVAR_VALUE
:
2231 addr
= value_contents_writeable (var
->u
.value
);
2234 modify_field (value_type (var
->u
.value
), addr
+ offset
,
2235 value_as_long (newval
), bitpos
, bitsize
);
2237 memcpy (addr
+ offset
, value_contents (newval
),
2238 TYPE_LENGTH (value_type (newval
)));
2242 /* We can never get a component of any other kind. */
2243 internal_error (__FILE__
, __LINE__
, _("set_internalvar_component"));
2248 set_internalvar (struct internalvar
*var
, struct value
*val
)
2250 enum internalvar_kind new_kind
;
2251 union internalvar_data new_data
= { 0 };
2253 if (var
->kind
== INTERNALVAR_FUNCTION
&& var
->u
.fn
.canonical
)
2254 error (_("Cannot overwrite convenience function %s"), var
->name
);
2256 /* Prepare new contents. */
2257 switch (TYPE_CODE (check_typedef (value_type (val
))))
2259 case TYPE_CODE_VOID
:
2260 new_kind
= INTERNALVAR_VOID
;
2263 case TYPE_CODE_INTERNAL_FUNCTION
:
2264 gdb_assert (VALUE_LVAL (val
) == lval_internalvar
);
2265 new_kind
= INTERNALVAR_FUNCTION
;
2266 get_internalvar_function (VALUE_INTERNALVAR (val
),
2267 &new_data
.fn
.function
);
2268 /* Copies created here are never canonical. */
2272 new_kind
= INTERNALVAR_VALUE
;
2273 new_data
.value
= value_copy (val
);
2274 new_data
.value
->modifiable
= 1;
2276 /* Force the value to be fetched from the target now, to avoid problems
2277 later when this internalvar is referenced and the target is gone or
2279 if (value_lazy (new_data
.value
))
2280 value_fetch_lazy (new_data
.value
);
2282 /* Release the value from the value chain to prevent it from being
2283 deleted by free_all_values. From here on this function should not
2284 call error () until new_data is installed into the var->u to avoid
2286 release_value (new_data
.value
);
2290 /* Clean up old contents. */
2291 clear_internalvar (var
);
2294 var
->kind
= new_kind
;
2296 /* End code which must not call error(). */
2300 set_internalvar_integer (struct internalvar
*var
, LONGEST l
)
2302 /* Clean up old contents. */
2303 clear_internalvar (var
);
2305 var
->kind
= INTERNALVAR_INTEGER
;
2306 var
->u
.integer
.type
= NULL
;
2307 var
->u
.integer
.val
= l
;
2311 set_internalvar_string (struct internalvar
*var
, const char *string
)
2313 /* Clean up old contents. */
2314 clear_internalvar (var
);
2316 var
->kind
= INTERNALVAR_STRING
;
2317 var
->u
.string
= xstrdup (string
);
2321 set_internalvar_function (struct internalvar
*var
, struct internal_function
*f
)
2323 /* Clean up old contents. */
2324 clear_internalvar (var
);
2326 var
->kind
= INTERNALVAR_FUNCTION
;
2327 var
->u
.fn
.function
= f
;
2328 var
->u
.fn
.canonical
= 1;
2329 /* Variables installed here are always the canonical version. */
2333 clear_internalvar (struct internalvar
*var
)
2335 /* Clean up old contents. */
2338 case INTERNALVAR_VALUE
:
2339 value_free (var
->u
.value
);
2342 case INTERNALVAR_STRING
:
2343 xfree (var
->u
.string
);
2346 case INTERNALVAR_MAKE_VALUE
:
2347 if (var
->u
.make_value
.functions
->destroy
!= NULL
)
2348 var
->u
.make_value
.functions
->destroy (var
->u
.make_value
.data
);
2355 /* Reset to void kind. */
2356 var
->kind
= INTERNALVAR_VOID
;
2360 internalvar_name (struct internalvar
*var
)
2365 static struct internal_function
*
2366 create_internal_function (const char *name
,
2367 internal_function_fn handler
, void *cookie
)
2369 struct internal_function
*ifn
= XNEW (struct internal_function
);
2371 ifn
->name
= xstrdup (name
);
2372 ifn
->handler
= handler
;
2373 ifn
->cookie
= cookie
;
2378 value_internal_function_name (struct value
*val
)
2380 struct internal_function
*ifn
;
2383 gdb_assert (VALUE_LVAL (val
) == lval_internalvar
);
2384 result
= get_internalvar_function (VALUE_INTERNALVAR (val
), &ifn
);
2385 gdb_assert (result
);
2391 call_internal_function (struct gdbarch
*gdbarch
,
2392 const struct language_defn
*language
,
2393 struct value
*func
, int argc
, struct value
**argv
)
2395 struct internal_function
*ifn
;
2398 gdb_assert (VALUE_LVAL (func
) == lval_internalvar
);
2399 result
= get_internalvar_function (VALUE_INTERNALVAR (func
), &ifn
);
2400 gdb_assert (result
);
2402 return (*ifn
->handler
) (gdbarch
, language
, ifn
->cookie
, argc
, argv
);
2405 /* The 'function' command. This does nothing -- it is just a
2406 placeholder to let "help function NAME" work. This is also used as
2407 the implementation of the sub-command that is created when
2408 registering an internal function. */
2410 function_command (char *command
, int from_tty
)
2415 /* Clean up if an internal function's command is destroyed. */
2417 function_destroyer (struct cmd_list_element
*self
, void *ignore
)
2419 xfree ((char *) self
->name
);
2420 xfree ((char *) self
->doc
);
2423 /* Add a new internal function. NAME is the name of the function; DOC
2424 is a documentation string describing the function. HANDLER is
2425 called when the function is invoked. COOKIE is an arbitrary
2426 pointer which is passed to HANDLER and is intended for "user
2429 add_internal_function (const char *name
, const char *doc
,
2430 internal_function_fn handler
, void *cookie
)
2432 struct cmd_list_element
*cmd
;
2433 struct internal_function
*ifn
;
2434 struct internalvar
*var
= lookup_internalvar (name
);
2436 ifn
= create_internal_function (name
, handler
, cookie
);
2437 set_internalvar_function (var
, ifn
);
2439 cmd
= add_cmd (xstrdup (name
), no_class
, function_command
, (char *) doc
,
2441 cmd
->destroyer
= function_destroyer
;
2444 /* Update VALUE before discarding OBJFILE. COPIED_TYPES is used to
2445 prevent cycles / duplicates. */
2448 preserve_one_value (struct value
*value
, struct objfile
*objfile
,
2449 htab_t copied_types
)
2451 if (TYPE_OBJFILE (value
->type
) == objfile
)
2452 value
->type
= copy_type_recursive (objfile
, value
->type
, copied_types
);
2454 if (TYPE_OBJFILE (value
->enclosing_type
) == objfile
)
2455 value
->enclosing_type
= copy_type_recursive (objfile
,
2456 value
->enclosing_type
,
2460 /* Likewise for internal variable VAR. */
2463 preserve_one_internalvar (struct internalvar
*var
, struct objfile
*objfile
,
2464 htab_t copied_types
)
2468 case INTERNALVAR_INTEGER
:
2469 if (var
->u
.integer
.type
&& TYPE_OBJFILE (var
->u
.integer
.type
) == objfile
)
2471 = copy_type_recursive (objfile
, var
->u
.integer
.type
, copied_types
);
2474 case INTERNALVAR_VALUE
:
2475 preserve_one_value (var
->u
.value
, objfile
, copied_types
);
2480 /* Update the internal variables and value history when OBJFILE is
2481 discarded; we must copy the types out of the objfile. New global types
2482 will be created for every convenience variable which currently points to
2483 this objfile's types, and the convenience variables will be adjusted to
2484 use the new global types. */
2487 preserve_values (struct objfile
*objfile
)
2489 htab_t copied_types
;
2490 struct value_history_chunk
*cur
;
2491 struct internalvar
*var
;
2494 /* Create the hash table. We allocate on the objfile's obstack, since
2495 it is soon to be deleted. */
2496 copied_types
= create_copied_types_hash (objfile
);
2498 for (cur
= value_history_chain
; cur
; cur
= cur
->next
)
2499 for (i
= 0; i
< VALUE_HISTORY_CHUNK
; i
++)
2501 preserve_one_value (cur
->values
[i
], objfile
, copied_types
);
2503 for (var
= internalvars
; var
; var
= var
->next
)
2504 preserve_one_internalvar (var
, objfile
, copied_types
);
2506 preserve_ext_lang_values (objfile
, copied_types
);
2508 htab_delete (copied_types
);
2512 show_convenience (char *ignore
, int from_tty
)
2514 struct gdbarch
*gdbarch
= get_current_arch ();
2515 struct internalvar
*var
;
2517 struct value_print_options opts
;
2519 get_user_print_options (&opts
);
2520 for (var
= internalvars
; var
; var
= var
->next
)
2522 volatile struct gdb_exception ex
;
2528 printf_filtered (("$%s = "), var
->name
);
2530 TRY_CATCH (ex
, RETURN_MASK_ERROR
)
2534 val
= value_of_internalvar (gdbarch
, var
);
2535 value_print (val
, gdb_stdout
, &opts
);
2538 fprintf_filtered (gdb_stdout
, _("<error: %s>"), ex
.message
);
2539 printf_filtered (("\n"));
2543 /* This text does not mention convenience functions on purpose.
2544 The user can't create them except via Python, and if Python support
2545 is installed this message will never be printed ($_streq will
2547 printf_unfiltered (_("No debugger convenience variables now defined.\n"
2548 "Convenience variables have "
2549 "names starting with \"$\";\n"
2550 "use \"set\" as in \"set "
2551 "$foo = 5\" to define them.\n"));
2555 /* Return the TYPE_CODE_XMETHOD value corresponding to WORKER. */
2558 value_of_xmethod (struct xmethod_worker
*worker
)
2560 if (worker
->value
== NULL
)
2564 v
= allocate_value (builtin_type (target_gdbarch ())->xmethod
);
2565 v
->lval
= lval_xcallable
;
2566 v
->location
.xm_worker
= worker
;
2571 return worker
->value
;
2574 /* Call the xmethod corresponding to the TYPE_CODE_XMETHOD value METHOD. */
2577 call_xmethod (struct value
*method
, int argc
, struct value
**argv
)
2579 gdb_assert (TYPE_CODE (value_type (method
)) == TYPE_CODE_XMETHOD
2580 && method
->lval
== lval_xcallable
&& argc
> 0);
2582 return invoke_xmethod (method
->location
.xm_worker
,
2583 argv
[0], argv
+ 1, argc
- 1);
2586 /* Extract a value as a C number (either long or double).
2587 Knows how to convert fixed values to double, or
2588 floating values to long.
2589 Does not deallocate the value. */
2592 value_as_long (struct value
*val
)
2594 /* This coerces arrays and functions, which is necessary (e.g.
2595 in disassemble_command). It also dereferences references, which
2596 I suspect is the most logical thing to do. */
2597 val
= coerce_array (val
);
2598 return unpack_long (value_type (val
), value_contents (val
));
2602 value_as_double (struct value
*val
)
2607 foo
= unpack_double (value_type (val
), value_contents (val
), &inv
);
2609 error (_("Invalid floating value found in program."));
2613 /* Extract a value as a C pointer. Does not deallocate the value.
2614 Note that val's type may not actually be a pointer; value_as_long
2615 handles all the cases. */
2617 value_as_address (struct value
*val
)
2619 struct gdbarch
*gdbarch
= get_type_arch (value_type (val
));
2621 /* Assume a CORE_ADDR can fit in a LONGEST (for now). Not sure
2622 whether we want this to be true eventually. */
2624 /* gdbarch_addr_bits_remove is wrong if we are being called for a
2625 non-address (e.g. argument to "signal", "info break", etc.), or
2626 for pointers to char, in which the low bits *are* significant. */
2627 return gdbarch_addr_bits_remove (gdbarch
, value_as_long (val
));
2630 /* There are several targets (IA-64, PowerPC, and others) which
2631 don't represent pointers to functions as simply the address of
2632 the function's entry point. For example, on the IA-64, a
2633 function pointer points to a two-word descriptor, generated by
2634 the linker, which contains the function's entry point, and the
2635 value the IA-64 "global pointer" register should have --- to
2636 support position-independent code. The linker generates
2637 descriptors only for those functions whose addresses are taken.
2639 On such targets, it's difficult for GDB to convert an arbitrary
2640 function address into a function pointer; it has to either find
2641 an existing descriptor for that function, or call malloc and
2642 build its own. On some targets, it is impossible for GDB to
2643 build a descriptor at all: the descriptor must contain a jump
2644 instruction; data memory cannot be executed; and code memory
2647 Upon entry to this function, if VAL is a value of type `function'
2648 (that is, TYPE_CODE (VALUE_TYPE (val)) == TYPE_CODE_FUNC), then
2649 value_address (val) is the address of the function. This is what
2650 you'll get if you evaluate an expression like `main'. The call
2651 to COERCE_ARRAY below actually does all the usual unary
2652 conversions, which includes converting values of type `function'
2653 to `pointer to function'. This is the challenging conversion
2654 discussed above. Then, `unpack_long' will convert that pointer
2655 back into an address.
2657 So, suppose the user types `disassemble foo' on an architecture
2658 with a strange function pointer representation, on which GDB
2659 cannot build its own descriptors, and suppose further that `foo'
2660 has no linker-built descriptor. The address->pointer conversion
2661 will signal an error and prevent the command from running, even
2662 though the next step would have been to convert the pointer
2663 directly back into the same address.
2665 The following shortcut avoids this whole mess. If VAL is a
2666 function, just return its address directly. */
2667 if (TYPE_CODE (value_type (val
)) == TYPE_CODE_FUNC
2668 || TYPE_CODE (value_type (val
)) == TYPE_CODE_METHOD
)
2669 return value_address (val
);
2671 val
= coerce_array (val
);
2673 /* Some architectures (e.g. Harvard), map instruction and data
2674 addresses onto a single large unified address space. For
2675 instance: An architecture may consider a large integer in the
2676 range 0x10000000 .. 0x1000ffff to already represent a data
2677 addresses (hence not need a pointer to address conversion) while
2678 a small integer would still need to be converted integer to
2679 pointer to address. Just assume such architectures handle all
2680 integer conversions in a single function. */
2684 I think INTEGER_TO_ADDRESS is a good idea as proposed --- but we
2685 must admonish GDB hackers to make sure its behavior matches the
2686 compiler's, whenever possible.
2688 In general, I think GDB should evaluate expressions the same way
2689 the compiler does. When the user copies an expression out of
2690 their source code and hands it to a `print' command, they should
2691 get the same value the compiler would have computed. Any
2692 deviation from this rule can cause major confusion and annoyance,
2693 and needs to be justified carefully. In other words, GDB doesn't
2694 really have the freedom to do these conversions in clever and
2697 AndrewC pointed out that users aren't complaining about how GDB
2698 casts integers to pointers; they are complaining that they can't
2699 take an address from a disassembly listing and give it to `x/i'.
2700 This is certainly important.
2702 Adding an architecture method like integer_to_address() certainly
2703 makes it possible for GDB to "get it right" in all circumstances
2704 --- the target has complete control over how things get done, so
2705 people can Do The Right Thing for their target without breaking
2706 anyone else. The standard doesn't specify how integers get
2707 converted to pointers; usually, the ABI doesn't either, but
2708 ABI-specific code is a more reasonable place to handle it. */
2710 if (TYPE_CODE (value_type (val
)) != TYPE_CODE_PTR
2711 && TYPE_CODE (value_type (val
)) != TYPE_CODE_REF
2712 && gdbarch_integer_to_address_p (gdbarch
))
2713 return gdbarch_integer_to_address (gdbarch
, value_type (val
),
2714 value_contents (val
));
2716 return unpack_long (value_type (val
), value_contents (val
));
2720 /* Unpack raw data (copied from debugee, target byte order) at VALADDR
2721 as a long, or as a double, assuming the raw data is described
2722 by type TYPE. Knows how to convert different sizes of values
2723 and can convert between fixed and floating point. We don't assume
2724 any alignment for the raw data. Return value is in host byte order.
2726 If you want functions and arrays to be coerced to pointers, and
2727 references to be dereferenced, call value_as_long() instead.
2729 C++: It is assumed that the front-end has taken care of
2730 all matters concerning pointers to members. A pointer
2731 to member which reaches here is considered to be equivalent
2732 to an INT (or some size). After all, it is only an offset. */
2735 unpack_long (struct type
*type
, const gdb_byte
*valaddr
)
2737 enum bfd_endian byte_order
= gdbarch_byte_order (get_type_arch (type
));
2738 enum type_code code
= TYPE_CODE (type
);
2739 int len
= TYPE_LENGTH (type
);
2740 int nosign
= TYPE_UNSIGNED (type
);
2744 case TYPE_CODE_TYPEDEF
:
2745 return unpack_long (check_typedef (type
), valaddr
);
2746 case TYPE_CODE_ENUM
:
2747 case TYPE_CODE_FLAGS
:
2748 case TYPE_CODE_BOOL
:
2750 case TYPE_CODE_CHAR
:
2751 case TYPE_CODE_RANGE
:
2752 case TYPE_CODE_MEMBERPTR
:
2754 return extract_unsigned_integer (valaddr
, len
, byte_order
);
2756 return extract_signed_integer (valaddr
, len
, byte_order
);
2759 return extract_typed_floating (valaddr
, type
);
2761 case TYPE_CODE_DECFLOAT
:
2762 /* libdecnumber has a function to convert from decimal to integer, but
2763 it doesn't work when the decimal number has a fractional part. */
2764 return decimal_to_doublest (valaddr
, len
, byte_order
);
2768 /* Assume a CORE_ADDR can fit in a LONGEST (for now). Not sure
2769 whether we want this to be true eventually. */
2770 return extract_typed_address (valaddr
, type
);
2773 error (_("Value can't be converted to integer."));
2775 return 0; /* Placate lint. */
2778 /* Return a double value from the specified type and address.
2779 INVP points to an int which is set to 0 for valid value,
2780 1 for invalid value (bad float format). In either case,
2781 the returned double is OK to use. Argument is in target
2782 format, result is in host format. */
2785 unpack_double (struct type
*type
, const gdb_byte
*valaddr
, int *invp
)
2787 enum bfd_endian byte_order
= gdbarch_byte_order (get_type_arch (type
));
2788 enum type_code code
;
2792 *invp
= 0; /* Assume valid. */
2793 CHECK_TYPEDEF (type
);
2794 code
= TYPE_CODE (type
);
2795 len
= TYPE_LENGTH (type
);
2796 nosign
= TYPE_UNSIGNED (type
);
2797 if (code
== TYPE_CODE_FLT
)
2799 /* NOTE: cagney/2002-02-19: There was a test here to see if the
2800 floating-point value was valid (using the macro
2801 INVALID_FLOAT). That test/macro have been removed.
2803 It turns out that only the VAX defined this macro and then
2804 only in a non-portable way. Fixing the portability problem
2805 wouldn't help since the VAX floating-point code is also badly
2806 bit-rotten. The target needs to add definitions for the
2807 methods gdbarch_float_format and gdbarch_double_format - these
2808 exactly describe the target floating-point format. The
2809 problem here is that the corresponding floatformat_vax_f and
2810 floatformat_vax_d values these methods should be set to are
2811 also not defined either. Oops!
2813 Hopefully someone will add both the missing floatformat
2814 definitions and the new cases for floatformat_is_valid (). */
2816 if (!floatformat_is_valid (floatformat_from_type (type
), valaddr
))
2822 return extract_typed_floating (valaddr
, type
);
2824 else if (code
== TYPE_CODE_DECFLOAT
)
2825 return decimal_to_doublest (valaddr
, len
, byte_order
);
2828 /* Unsigned -- be sure we compensate for signed LONGEST. */
2829 return (ULONGEST
) unpack_long (type
, valaddr
);
2833 /* Signed -- we are OK with unpack_long. */
2834 return unpack_long (type
, valaddr
);
2838 /* Unpack raw data (copied from debugee, target byte order) at VALADDR
2839 as a CORE_ADDR, assuming the raw data is described by type TYPE.
2840 We don't assume any alignment for the raw data. Return value is in
2843 If you want functions and arrays to be coerced to pointers, and
2844 references to be dereferenced, call value_as_address() instead.
2846 C++: It is assumed that the front-end has taken care of
2847 all matters concerning pointers to members. A pointer
2848 to member which reaches here is considered to be equivalent
2849 to an INT (or some size). After all, it is only an offset. */
2852 unpack_pointer (struct type
*type
, const gdb_byte
*valaddr
)
2854 /* Assume a CORE_ADDR can fit in a LONGEST (for now). Not sure
2855 whether we want this to be true eventually. */
2856 return unpack_long (type
, valaddr
);
2860 /* Get the value of the FIELDNO'th field (which must be static) of
2864 value_static_field (struct type
*type
, int fieldno
)
2866 struct value
*retval
;
2868 switch (TYPE_FIELD_LOC_KIND (type
, fieldno
))
2870 case FIELD_LOC_KIND_PHYSADDR
:
2871 retval
= value_at_lazy (TYPE_FIELD_TYPE (type
, fieldno
),
2872 TYPE_FIELD_STATIC_PHYSADDR (type
, fieldno
));
2874 case FIELD_LOC_KIND_PHYSNAME
:
2876 const char *phys_name
= TYPE_FIELD_STATIC_PHYSNAME (type
, fieldno
);
2877 /* TYPE_FIELD_NAME (type, fieldno); */
2878 struct symbol
*sym
= lookup_symbol (phys_name
, 0, VAR_DOMAIN
, 0);
2882 /* With some compilers, e.g. HP aCC, static data members are
2883 reported as non-debuggable symbols. */
2884 struct bound_minimal_symbol msym
2885 = lookup_minimal_symbol (phys_name
, NULL
, NULL
);
2888 return allocate_optimized_out_value (type
);
2891 retval
= value_at_lazy (TYPE_FIELD_TYPE (type
, fieldno
),
2892 BMSYMBOL_VALUE_ADDRESS (msym
));
2896 retval
= value_of_variable (sym
, NULL
);
2900 gdb_assert_not_reached ("unexpected field location kind");
2906 /* Change the enclosing type of a value object VAL to NEW_ENCL_TYPE.
2907 You have to be careful here, since the size of the data area for the value
2908 is set by the length of the enclosing type. So if NEW_ENCL_TYPE is bigger
2909 than the old enclosing type, you have to allocate more space for the
2913 set_value_enclosing_type (struct value
*val
, struct type
*new_encl_type
)
2915 if (TYPE_LENGTH (new_encl_type
) > TYPE_LENGTH (value_enclosing_type (val
)))
2917 (gdb_byte
*) xrealloc (val
->contents
, TYPE_LENGTH (new_encl_type
));
2919 val
->enclosing_type
= new_encl_type
;
2922 /* Given a value ARG1 (offset by OFFSET bytes)
2923 of a struct or union type ARG_TYPE,
2924 extract and return the value of one of its (non-static) fields.
2925 FIELDNO says which field. */
2928 value_primitive_field (struct value
*arg1
, int offset
,
2929 int fieldno
, struct type
*arg_type
)
2934 CHECK_TYPEDEF (arg_type
);
2935 type
= TYPE_FIELD_TYPE (arg_type
, fieldno
);
2937 /* Call check_typedef on our type to make sure that, if TYPE
2938 is a TYPE_CODE_TYPEDEF, its length is set to the length
2939 of the target type instead of zero. However, we do not
2940 replace the typedef type by the target type, because we want
2941 to keep the typedef in order to be able to print the type
2942 description correctly. */
2943 check_typedef (type
);
2945 if (TYPE_FIELD_BITSIZE (arg_type
, fieldno
))
2947 /* Handle packed fields.
2949 Create a new value for the bitfield, with bitpos and bitsize
2950 set. If possible, arrange offset and bitpos so that we can
2951 do a single aligned read of the size of the containing type.
2952 Otherwise, adjust offset to the byte containing the first
2953 bit. Assume that the address, offset, and embedded offset
2954 are sufficiently aligned. */
2956 int bitpos
= TYPE_FIELD_BITPOS (arg_type
, fieldno
);
2957 int container_bitsize
= TYPE_LENGTH (type
) * 8;
2959 v
= allocate_value_lazy (type
);
2960 v
->bitsize
= TYPE_FIELD_BITSIZE (arg_type
, fieldno
);
2961 if ((bitpos
% container_bitsize
) + v
->bitsize
<= container_bitsize
2962 && TYPE_LENGTH (type
) <= (int) sizeof (LONGEST
))
2963 v
->bitpos
= bitpos
% container_bitsize
;
2965 v
->bitpos
= bitpos
% 8;
2966 v
->offset
= (value_embedded_offset (arg1
)
2968 + (bitpos
- v
->bitpos
) / 8);
2969 set_value_parent (v
, arg1
);
2970 if (!value_lazy (arg1
))
2971 value_fetch_lazy (v
);
2973 else if (fieldno
< TYPE_N_BASECLASSES (arg_type
))
2975 /* This field is actually a base subobject, so preserve the
2976 entire object's contents for later references to virtual
2980 /* Lazy register values with offsets are not supported. */
2981 if (VALUE_LVAL (arg1
) == lval_register
&& value_lazy (arg1
))
2982 value_fetch_lazy (arg1
);
2984 /* We special case virtual inheritance here because this
2985 requires access to the contents, which we would rather avoid
2986 for references to ordinary fields of unavailable values. */
2987 if (BASETYPE_VIA_VIRTUAL (arg_type
, fieldno
))
2988 boffset
= baseclass_offset (arg_type
, fieldno
,
2989 value_contents (arg1
),
2990 value_embedded_offset (arg1
),
2991 value_address (arg1
),
2994 boffset
= TYPE_FIELD_BITPOS (arg_type
, fieldno
) / 8;
2996 if (value_lazy (arg1
))
2997 v
= allocate_value_lazy (value_enclosing_type (arg1
));
3000 v
= allocate_value (value_enclosing_type (arg1
));
3001 value_contents_copy_raw (v
, 0, arg1
, 0,
3002 TYPE_LENGTH (value_enclosing_type (arg1
)));
3005 v
->offset
= value_offset (arg1
);
3006 v
->embedded_offset
= offset
+ value_embedded_offset (arg1
) + boffset
;
3010 /* Plain old data member */
3011 offset
+= TYPE_FIELD_BITPOS (arg_type
, fieldno
) / 8;
3013 /* Lazy register values with offsets are not supported. */
3014 if (VALUE_LVAL (arg1
) == lval_register
&& value_lazy (arg1
))
3015 value_fetch_lazy (arg1
);
3017 if (value_lazy (arg1
))
3018 v
= allocate_value_lazy (type
);
3021 v
= allocate_value (type
);
3022 value_contents_copy_raw (v
, value_embedded_offset (v
),
3023 arg1
, value_embedded_offset (arg1
) + offset
,
3024 TYPE_LENGTH (type
));
3026 v
->offset
= (value_offset (arg1
) + offset
3027 + value_embedded_offset (arg1
));
3029 set_value_component_location (v
, arg1
);
3030 VALUE_REGNUM (v
) = VALUE_REGNUM (arg1
);
3031 VALUE_FRAME_ID (v
) = VALUE_FRAME_ID (arg1
);
3035 /* Given a value ARG1 of a struct or union type,
3036 extract and return the value of one of its (non-static) fields.
3037 FIELDNO says which field. */
3040 value_field (struct value
*arg1
, int fieldno
)
3042 return value_primitive_field (arg1
, 0, fieldno
, value_type (arg1
));
3045 /* Return a non-virtual function as a value.
3046 F is the list of member functions which contains the desired method.
3047 J is an index into F which provides the desired method.
3049 We only use the symbol for its address, so be happy with either a
3050 full symbol or a minimal symbol. */
3053 value_fn_field (struct value
**arg1p
, struct fn_field
*f
,
3054 int j
, struct type
*type
,
3058 struct type
*ftype
= TYPE_FN_FIELD_TYPE (f
, j
);
3059 const char *physname
= TYPE_FN_FIELD_PHYSNAME (f
, j
);
3061 struct bound_minimal_symbol msym
;
3063 sym
= lookup_symbol (physname
, 0, VAR_DOMAIN
, 0);
3066 memset (&msym
, 0, sizeof (msym
));
3070 gdb_assert (sym
== NULL
);
3071 msym
= lookup_bound_minimal_symbol (physname
);
3072 if (msym
.minsym
== NULL
)
3076 v
= allocate_value (ftype
);
3079 set_value_address (v
, BLOCK_START (SYMBOL_BLOCK_VALUE (sym
)));
3083 /* The minimal symbol might point to a function descriptor;
3084 resolve it to the actual code address instead. */
3085 struct objfile
*objfile
= msym
.objfile
;
3086 struct gdbarch
*gdbarch
= get_objfile_arch (objfile
);
3088 set_value_address (v
,
3089 gdbarch_convert_from_func_ptr_addr
3090 (gdbarch
, BMSYMBOL_VALUE_ADDRESS (msym
), ¤t_target
));
3095 if (type
!= value_type (*arg1p
))
3096 *arg1p
= value_ind (value_cast (lookup_pointer_type (type
),
3097 value_addr (*arg1p
)));
3099 /* Move the `this' pointer according to the offset.
3100 VALUE_OFFSET (*arg1p) += offset; */
3108 /* Helper function for both unpack_value_bits_as_long and
3109 unpack_bits_as_long. See those functions for more details on the
3110 interface; the only difference is that this function accepts either
3111 a NULL or a non-NULL ORIGINAL_VALUE. */
3114 unpack_value_bits_as_long_1 (struct type
*field_type
, const gdb_byte
*valaddr
,
3115 int embedded_offset
, int bitpos
, int bitsize
,
3116 const struct value
*original_value
,
3119 enum bfd_endian byte_order
= gdbarch_byte_order (get_type_arch (field_type
));
3126 /* Read the minimum number of bytes required; there may not be
3127 enough bytes to read an entire ULONGEST. */
3128 CHECK_TYPEDEF (field_type
);
3130 bytes_read
= ((bitpos
% 8) + bitsize
+ 7) / 8;
3132 bytes_read
= TYPE_LENGTH (field_type
);
3134 read_offset
= bitpos
/ 8;
3136 if (original_value
!= NULL
3137 && !value_bits_available (original_value
, embedded_offset
+ bitpos
,
3141 val
= extract_unsigned_integer (valaddr
+ embedded_offset
+ read_offset
,
3142 bytes_read
, byte_order
);
3144 /* Extract bits. See comment above. */
3146 if (gdbarch_bits_big_endian (get_type_arch (field_type
)))
3147 lsbcount
= (bytes_read
* 8 - bitpos
% 8 - bitsize
);
3149 lsbcount
= (bitpos
% 8);
3152 /* If the field does not entirely fill a LONGEST, then zero the sign bits.
3153 If the field is signed, and is negative, then sign extend. */
3155 if ((bitsize
> 0) && (bitsize
< 8 * (int) sizeof (val
)))
3157 valmask
= (((ULONGEST
) 1) << bitsize
) - 1;
3159 if (!TYPE_UNSIGNED (field_type
))
3161 if (val
& (valmask
^ (valmask
>> 1)))
3172 /* Unpack a bitfield of the specified FIELD_TYPE, from the object at
3173 VALADDR + EMBEDDED_OFFSET, and store the result in *RESULT.
3174 VALADDR points to the contents of ORIGINAL_VALUE, which must not be
3175 NULL. The bitfield starts at BITPOS bits and contains BITSIZE
3178 Returns false if the value contents are unavailable, otherwise
3179 returns true, indicating a valid value has been stored in *RESULT.
3181 Extracting bits depends on endianness of the machine. Compute the
3182 number of least significant bits to discard. For big endian machines,
3183 we compute the total number of bits in the anonymous object, subtract
3184 off the bit count from the MSB of the object to the MSB of the
3185 bitfield, then the size of the bitfield, which leaves the LSB discard
3186 count. For little endian machines, the discard count is simply the
3187 number of bits from the LSB of the anonymous object to the LSB of the
3190 If the field is signed, we also do sign extension. */
3193 unpack_value_bits_as_long (struct type
*field_type
, const gdb_byte
*valaddr
,
3194 int embedded_offset
, int bitpos
, int bitsize
,
3195 const struct value
*original_value
,
3198 gdb_assert (original_value
!= NULL
);
3200 return unpack_value_bits_as_long_1 (field_type
, valaddr
, embedded_offset
,
3201 bitpos
, bitsize
, original_value
, result
);
3205 /* Unpack a field FIELDNO of the specified TYPE, from the object at
3206 VALADDR + EMBEDDED_OFFSET. VALADDR points to the contents of
3207 ORIGINAL_VALUE. See unpack_value_bits_as_long for more
3211 unpack_value_field_as_long_1 (struct type
*type
, const gdb_byte
*valaddr
,
3212 int embedded_offset
, int fieldno
,
3213 const struct value
*val
, LONGEST
*result
)
3215 int bitpos
= TYPE_FIELD_BITPOS (type
, fieldno
);
3216 int bitsize
= TYPE_FIELD_BITSIZE (type
, fieldno
);
3217 struct type
*field_type
= TYPE_FIELD_TYPE (type
, fieldno
);
3219 return unpack_value_bits_as_long_1 (field_type
, valaddr
, embedded_offset
,
3220 bitpos
, bitsize
, val
,
3224 /* Unpack a field FIELDNO of the specified TYPE, from the object at
3225 VALADDR + EMBEDDED_OFFSET. VALADDR points to the contents of
3226 ORIGINAL_VALUE, which must not be NULL. See
3227 unpack_value_bits_as_long for more details. */
3230 unpack_value_field_as_long (struct type
*type
, const gdb_byte
*valaddr
,
3231 int embedded_offset
, int fieldno
,
3232 const struct value
*val
, LONGEST
*result
)
3234 gdb_assert (val
!= NULL
);
3236 return unpack_value_field_as_long_1 (type
, valaddr
, embedded_offset
,
3237 fieldno
, val
, result
);
3240 /* Unpack a field FIELDNO of the specified TYPE, from the anonymous
3241 object at VALADDR. See unpack_value_bits_as_long for more details.
3242 This function differs from unpack_value_field_as_long in that it
3243 operates without a struct value object. */
3246 unpack_field_as_long (struct type
*type
, const gdb_byte
*valaddr
, int fieldno
)
3250 unpack_value_field_as_long_1 (type
, valaddr
, 0, fieldno
, NULL
, &result
);
3254 /* Return a new value with type TYPE, which is FIELDNO field of the
3255 object at VALADDR + EMBEDDEDOFFSET. VALADDR points to the contents
3256 of VAL. If the VAL's contents required to extract the bitfield
3257 from are unavailable, the new value is correspondingly marked as
3261 value_field_bitfield (struct type
*type
, int fieldno
,
3262 const gdb_byte
*valaddr
,
3263 int embedded_offset
, const struct value
*val
)
3267 if (!unpack_value_field_as_long (type
, valaddr
, embedded_offset
, fieldno
,
3270 struct type
*field_type
= TYPE_FIELD_TYPE (type
, fieldno
);
3271 struct value
*retval
= allocate_value (field_type
);
3272 mark_value_bytes_unavailable (retval
, 0, TYPE_LENGTH (field_type
));
3277 return value_from_longest (TYPE_FIELD_TYPE (type
, fieldno
), l
);
3281 /* Modify the value of a bitfield. ADDR points to a block of memory in
3282 target byte order; the bitfield starts in the byte pointed to. FIELDVAL
3283 is the desired value of the field, in host byte order. BITPOS and BITSIZE
3284 indicate which bits (in target bit order) comprise the bitfield.
3285 Requires 0 < BITSIZE <= lbits, 0 <= BITPOS % 8 + BITSIZE <= lbits, and
3286 0 <= BITPOS, where lbits is the size of a LONGEST in bits. */
3289 modify_field (struct type
*type
, gdb_byte
*addr
,
3290 LONGEST fieldval
, int bitpos
, int bitsize
)
3292 enum bfd_endian byte_order
= gdbarch_byte_order (get_type_arch (type
));
3294 ULONGEST mask
= (ULONGEST
) -1 >> (8 * sizeof (ULONGEST
) - bitsize
);
3297 /* Normalize BITPOS. */
3301 /* If a negative fieldval fits in the field in question, chop
3302 off the sign extension bits. */
3303 if ((~fieldval
& ~(mask
>> 1)) == 0)
3306 /* Warn if value is too big to fit in the field in question. */
3307 if (0 != (fieldval
& ~mask
))
3309 /* FIXME: would like to include fieldval in the message, but
3310 we don't have a sprintf_longest. */
3311 warning (_("Value does not fit in %d bits."), bitsize
);
3313 /* Truncate it, otherwise adjoining fields may be corrupted. */
3317 /* Ensure no bytes outside of the modified ones get accessed as it may cause
3318 false valgrind reports. */
3320 bytesize
= (bitpos
+ bitsize
+ 7) / 8;
3321 oword
= extract_unsigned_integer (addr
, bytesize
, byte_order
);
3323 /* Shifting for bit field depends on endianness of the target machine. */
3324 if (gdbarch_bits_big_endian (get_type_arch (type
)))
3325 bitpos
= bytesize
* 8 - bitpos
- bitsize
;
3327 oword
&= ~(mask
<< bitpos
);
3328 oword
|= fieldval
<< bitpos
;
3330 store_unsigned_integer (addr
, bytesize
, byte_order
, oword
);
3333 /* Pack NUM into BUF using a target format of TYPE. */
3336 pack_long (gdb_byte
*buf
, struct type
*type
, LONGEST num
)
3338 enum bfd_endian byte_order
= gdbarch_byte_order (get_type_arch (type
));
3341 type
= check_typedef (type
);
3342 len
= TYPE_LENGTH (type
);
3344 switch (TYPE_CODE (type
))
3347 case TYPE_CODE_CHAR
:
3348 case TYPE_CODE_ENUM
:
3349 case TYPE_CODE_FLAGS
:
3350 case TYPE_CODE_BOOL
:
3351 case TYPE_CODE_RANGE
:
3352 case TYPE_CODE_MEMBERPTR
:
3353 store_signed_integer (buf
, len
, byte_order
, num
);
3358 store_typed_address (buf
, type
, (CORE_ADDR
) num
);
3362 error (_("Unexpected type (%d) encountered for integer constant."),
3368 /* Pack NUM into BUF using a target format of TYPE. */
3371 pack_unsigned_long (gdb_byte
*buf
, struct type
*type
, ULONGEST num
)
3374 enum bfd_endian byte_order
;
3376 type
= check_typedef (type
);
3377 len
= TYPE_LENGTH (type
);
3378 byte_order
= gdbarch_byte_order (get_type_arch (type
));
3380 switch (TYPE_CODE (type
))
3383 case TYPE_CODE_CHAR
:
3384 case TYPE_CODE_ENUM
:
3385 case TYPE_CODE_FLAGS
:
3386 case TYPE_CODE_BOOL
:
3387 case TYPE_CODE_RANGE
:
3388 case TYPE_CODE_MEMBERPTR
:
3389 store_unsigned_integer (buf
, len
, byte_order
, num
);
3394 store_typed_address (buf
, type
, (CORE_ADDR
) num
);
3398 error (_("Unexpected type (%d) encountered "
3399 "for unsigned integer constant."),
3405 /* Convert C numbers into newly allocated values. */
3408 value_from_longest (struct type
*type
, LONGEST num
)
3410 struct value
*val
= allocate_value (type
);
3412 pack_long (value_contents_raw (val
), type
, num
);
3417 /* Convert C unsigned numbers into newly allocated values. */
3420 value_from_ulongest (struct type
*type
, ULONGEST num
)
3422 struct value
*val
= allocate_value (type
);
3424 pack_unsigned_long (value_contents_raw (val
), type
, num
);
3430 /* Create a value representing a pointer of type TYPE to the address
3434 value_from_pointer (struct type
*type
, CORE_ADDR addr
)
3436 struct value
*val
= allocate_value (type
);
3438 store_typed_address (value_contents_raw (val
),
3439 check_typedef (type
), addr
);
3444 /* Create a value of type TYPE whose contents come from VALADDR, if it
3445 is non-null, and whose memory address (in the inferior) is
3446 ADDRESS. The type of the created value may differ from the passed
3447 type TYPE. Make sure to retrieve values new type after this call.
3448 Note that TYPE is not passed through resolve_dynamic_type; this is
3449 a special API intended for use only by Ada. */
3452 value_from_contents_and_address_unresolved (struct type
*type
,
3453 const gdb_byte
*valaddr
,
3458 if (valaddr
== NULL
)
3459 v
= allocate_value_lazy (type
);
3461 v
= value_from_contents (type
, valaddr
);
3462 set_value_address (v
, address
);
3463 VALUE_LVAL (v
) = lval_memory
;
3467 /* Create a value of type TYPE whose contents come from VALADDR, if it
3468 is non-null, and whose memory address (in the inferior) is
3469 ADDRESS. The type of the created value may differ from the passed
3470 type TYPE. Make sure to retrieve values new type after this call. */
3473 value_from_contents_and_address (struct type
*type
,
3474 const gdb_byte
*valaddr
,
3477 struct type
*resolved_type
= resolve_dynamic_type (type
, address
);
3480 if (valaddr
== NULL
)
3481 v
= allocate_value_lazy (resolved_type
);
3483 v
= value_from_contents (resolved_type
, valaddr
);
3484 if (TYPE_DATA_LOCATION (resolved_type
) != NULL
3485 && TYPE_DATA_LOCATION_KIND (resolved_type
) == PROP_CONST
)
3486 address
= TYPE_DATA_LOCATION_ADDR (resolved_type
);
3487 set_value_address (v
, address
);
3488 VALUE_LVAL (v
) = lval_memory
;
3492 /* Create a value of type TYPE holding the contents CONTENTS.
3493 The new value is `not_lval'. */
3496 value_from_contents (struct type
*type
, const gdb_byte
*contents
)
3498 struct value
*result
;
3500 result
= allocate_value (type
);
3501 memcpy (value_contents_raw (result
), contents
, TYPE_LENGTH (type
));
3506 value_from_double (struct type
*type
, DOUBLEST num
)
3508 struct value
*val
= allocate_value (type
);
3509 struct type
*base_type
= check_typedef (type
);
3510 enum type_code code
= TYPE_CODE (base_type
);
3512 if (code
== TYPE_CODE_FLT
)
3514 store_typed_floating (value_contents_raw (val
), base_type
, num
);
3517 error (_("Unexpected type encountered for floating constant."));
3523 value_from_decfloat (struct type
*type
, const gdb_byte
*dec
)
3525 struct value
*val
= allocate_value (type
);
3527 memcpy (value_contents_raw (val
), dec
, TYPE_LENGTH (type
));
3531 /* Extract a value from the history file. Input will be of the form
3532 $digits or $$digits. See block comment above 'write_dollar_variable'
3536 value_from_history_ref (const char *h
, const char **endp
)
3548 /* Find length of numeral string. */
3549 for (; isdigit (h
[len
]); len
++)
3552 /* Make sure numeral string is not part of an identifier. */
3553 if (h
[len
] == '_' || isalpha (h
[len
]))
3556 /* Now collect the index value. */
3561 /* For some bizarre reason, "$$" is equivalent to "$$1",
3562 rather than to "$$0" as it ought to be! */
3570 index
= -strtol (&h
[2], &local_end
, 10);
3578 /* "$" is equivalent to "$0". */
3586 index
= strtol (&h
[1], &local_end
, 10);
3591 return access_value_history (index
);
3595 coerce_ref_if_computed (const struct value
*arg
)
3597 const struct lval_funcs
*funcs
;
3599 if (TYPE_CODE (check_typedef (value_type (arg
))) != TYPE_CODE_REF
)
3602 if (value_lval_const (arg
) != lval_computed
)
3605 funcs
= value_computed_funcs (arg
);
3606 if (funcs
->coerce_ref
== NULL
)
3609 return funcs
->coerce_ref (arg
);
3612 /* Look at value.h for description. */
3615 readjust_indirect_value_type (struct value
*value
, struct type
*enc_type
,
3616 struct type
*original_type
,
3617 struct value
*original_value
)
3619 /* Re-adjust type. */
3620 deprecated_set_value_type (value
, TYPE_TARGET_TYPE (original_type
));
3622 /* Add embedding info. */
3623 set_value_enclosing_type (value
, enc_type
);
3624 set_value_embedded_offset (value
, value_pointed_to_offset (original_value
));
3626 /* We may be pointing to an object of some derived type. */
3627 return value_full_object (value
, NULL
, 0, 0, 0);
3631 coerce_ref (struct value
*arg
)
3633 struct type
*value_type_arg_tmp
= check_typedef (value_type (arg
));
3634 struct value
*retval
;
3635 struct type
*enc_type
;
3637 retval
= coerce_ref_if_computed (arg
);
3641 if (TYPE_CODE (value_type_arg_tmp
) != TYPE_CODE_REF
)
3644 enc_type
= check_typedef (value_enclosing_type (arg
));
3645 enc_type
= TYPE_TARGET_TYPE (enc_type
);
3647 retval
= value_at_lazy (enc_type
,
3648 unpack_pointer (value_type (arg
),
3649 value_contents (arg
)));
3650 enc_type
= value_type (retval
);
3651 return readjust_indirect_value_type (retval
, enc_type
,
3652 value_type_arg_tmp
, arg
);
3656 coerce_array (struct value
*arg
)
3660 arg
= coerce_ref (arg
);
3661 type
= check_typedef (value_type (arg
));
3663 switch (TYPE_CODE (type
))
3665 case TYPE_CODE_ARRAY
:
3666 if (!TYPE_VECTOR (type
) && current_language
->c_style_arrays
)
3667 arg
= value_coerce_array (arg
);
3669 case TYPE_CODE_FUNC
:
3670 arg
= value_coerce_function (arg
);
3677 /* Return the return value convention that will be used for the
3680 enum return_value_convention
3681 struct_return_convention (struct gdbarch
*gdbarch
,
3682 struct value
*function
, struct type
*value_type
)
3684 enum type_code code
= TYPE_CODE (value_type
);
3686 if (code
== TYPE_CODE_ERROR
)
3687 error (_("Function return type unknown."));
3689 /* Probe the architecture for the return-value convention. */
3690 return gdbarch_return_value (gdbarch
, function
, value_type
,
3694 /* Return true if the function returning the specified type is using
3695 the convention of returning structures in memory (passing in the
3696 address as a hidden first parameter). */
3699 using_struct_return (struct gdbarch
*gdbarch
,
3700 struct value
*function
, struct type
*value_type
)
3702 if (TYPE_CODE (value_type
) == TYPE_CODE_VOID
)
3703 /* A void return value is never in memory. See also corresponding
3704 code in "print_return_value". */
3707 return (struct_return_convention (gdbarch
, function
, value_type
)
3708 != RETURN_VALUE_REGISTER_CONVENTION
);
3711 /* Set the initialized field in a value struct. */
3714 set_value_initialized (struct value
*val
, int status
)
3716 val
->initialized
= status
;
3719 /* Return the initialized field in a value struct. */
3722 value_initialized (struct value
*val
)
3724 return val
->initialized
;
3727 /* Called only from the value_contents and value_contents_all()
3728 macros, if the current data for a variable needs to be loaded into
3729 value_contents(VAL). Fetches the data from the user's process, and
3730 clears the lazy flag to indicate that the data in the buffer is
3733 If the value is zero-length, we avoid calling read_memory, which
3734 would abort. We mark the value as fetched anyway -- all 0 bytes of
3737 This function returns a value because it is used in the
3738 value_contents macro as part of an expression, where a void would
3739 not work. The value is ignored. */
3742 value_fetch_lazy (struct value
*val
)
3744 gdb_assert (value_lazy (val
));
3745 allocate_value_contents (val
);
3746 /* A value is either lazy, or fully fetched. The
3747 availability/validity is only established as we try to fetch a
3749 gdb_assert (VEC_empty (range_s
, val
->optimized_out
));
3750 gdb_assert (VEC_empty (range_s
, val
->unavailable
));
3751 if (value_bitsize (val
))
3753 /* To read a lazy bitfield, read the entire enclosing value. This
3754 prevents reading the same block of (possibly volatile) memory once
3755 per bitfield. It would be even better to read only the containing
3756 word, but we have no way to record that just specific bits of a
3757 value have been fetched. */
3758 struct type
*type
= check_typedef (value_type (val
));
3759 enum bfd_endian byte_order
= gdbarch_byte_order (get_type_arch (type
));
3760 struct value
*parent
= value_parent (val
);
3761 LONGEST offset
= value_offset (val
);
3764 if (value_lazy (parent
))
3765 value_fetch_lazy (parent
);
3767 if (value_bits_any_optimized_out (parent
,
3768 TARGET_CHAR_BIT
* offset
+ value_bitpos (val
),
3769 value_bitsize (val
)))
3770 mark_value_bytes_optimized_out (val
, value_embedded_offset (val
),
3771 TYPE_LENGTH (type
));
3772 else if (!unpack_value_bits_as_long (value_type (val
),
3773 value_contents_for_printing (parent
),
3776 value_bitsize (val
), parent
, &num
))
3777 mark_value_bytes_unavailable (val
,
3778 value_embedded_offset (val
),
3779 TYPE_LENGTH (type
));
3781 store_signed_integer (value_contents_raw (val
), TYPE_LENGTH (type
),
3784 else if (VALUE_LVAL (val
) == lval_memory
)
3786 CORE_ADDR addr
= value_address (val
);
3787 struct type
*type
= check_typedef (value_enclosing_type (val
));
3789 if (TYPE_LENGTH (type
))
3790 read_value_memory (val
, 0, value_stack (val
),
3791 addr
, value_contents_all_raw (val
),
3792 TYPE_LENGTH (type
));
3794 else if (VALUE_LVAL (val
) == lval_register
)
3796 struct frame_info
*frame
;
3798 struct type
*type
= check_typedef (value_type (val
));
3799 struct value
*new_val
= val
, *mark
= value_mark ();
3801 /* Offsets are not supported here; lazy register values must
3802 refer to the entire register. */
3803 gdb_assert (value_offset (val
) == 0);
3805 while (VALUE_LVAL (new_val
) == lval_register
&& value_lazy (new_val
))
3807 struct frame_id frame_id
= VALUE_FRAME_ID (new_val
);
3809 frame
= frame_find_by_id (frame_id
);
3810 regnum
= VALUE_REGNUM (new_val
);
3812 gdb_assert (frame
!= NULL
);
3814 /* Convertible register routines are used for multi-register
3815 values and for interpretation in different types
3816 (e.g. float or int from a double register). Lazy
3817 register values should have the register's natural type,
3818 so they do not apply. */
3819 gdb_assert (!gdbarch_convert_register_p (get_frame_arch (frame
),
3822 new_val
= get_frame_register_value (frame
, regnum
);
3824 /* If we get another lazy lval_register value, it means the
3825 register is found by reading it from the next frame.
3826 get_frame_register_value should never return a value with
3827 the frame id pointing to FRAME. If it does, it means we
3828 either have two consecutive frames with the same frame id
3829 in the frame chain, or some code is trying to unwind
3830 behind get_prev_frame's back (e.g., a frame unwind
3831 sniffer trying to unwind), bypassing its validations. In
3832 any case, it should always be an internal error to end up
3833 in this situation. */
3834 if (VALUE_LVAL (new_val
) == lval_register
3835 && value_lazy (new_val
)
3836 && frame_id_eq (VALUE_FRAME_ID (new_val
), frame_id
))
3837 internal_error (__FILE__
, __LINE__
,
3838 _("infinite loop while fetching a register"));
3841 /* If it's still lazy (for instance, a saved register on the
3842 stack), fetch it. */
3843 if (value_lazy (new_val
))
3844 value_fetch_lazy (new_val
);
3846 /* Copy the contents and the unavailability/optimized-out
3847 meta-data from NEW_VAL to VAL. */
3848 set_value_lazy (val
, 0);
3849 value_contents_copy (val
, value_embedded_offset (val
),
3850 new_val
, value_embedded_offset (new_val
),
3851 TYPE_LENGTH (type
));
3855 struct gdbarch
*gdbarch
;
3856 frame
= frame_find_by_id (VALUE_FRAME_ID (val
));
3857 regnum
= VALUE_REGNUM (val
);
3858 gdbarch
= get_frame_arch (frame
);
3860 fprintf_unfiltered (gdb_stdlog
,
3861 "{ value_fetch_lazy "
3862 "(frame=%d,regnum=%d(%s),...) ",
3863 frame_relative_level (frame
), regnum
,
3864 user_reg_map_regnum_to_name (gdbarch
, regnum
));
3866 fprintf_unfiltered (gdb_stdlog
, "->");
3867 if (value_optimized_out (new_val
))
3869 fprintf_unfiltered (gdb_stdlog
, " ");
3870 val_print_optimized_out (new_val
, gdb_stdlog
);
3875 const gdb_byte
*buf
= value_contents (new_val
);
3877 if (VALUE_LVAL (new_val
) == lval_register
)
3878 fprintf_unfiltered (gdb_stdlog
, " register=%d",
3879 VALUE_REGNUM (new_val
));
3880 else if (VALUE_LVAL (new_val
) == lval_memory
)
3881 fprintf_unfiltered (gdb_stdlog
, " address=%s",
3883 value_address (new_val
)));
3885 fprintf_unfiltered (gdb_stdlog
, " computed");
3887 fprintf_unfiltered (gdb_stdlog
, " bytes=");
3888 fprintf_unfiltered (gdb_stdlog
, "[");
3889 for (i
= 0; i
< register_size (gdbarch
, regnum
); i
++)
3890 fprintf_unfiltered (gdb_stdlog
, "%02x", buf
[i
]);
3891 fprintf_unfiltered (gdb_stdlog
, "]");
3894 fprintf_unfiltered (gdb_stdlog
, " }\n");
3897 /* Dispose of the intermediate values. This prevents
3898 watchpoints from trying to watch the saved frame pointer. */
3899 value_free_to_mark (mark
);
3901 else if (VALUE_LVAL (val
) == lval_computed
3902 && value_computed_funcs (val
)->read
!= NULL
)
3903 value_computed_funcs (val
)->read (val
);
3905 internal_error (__FILE__
, __LINE__
, _("Unexpected lazy value type."));
3907 set_value_lazy (val
, 0);
3911 /* Implementation of the convenience function $_isvoid. */
3913 static struct value
*
3914 isvoid_internal_fn (struct gdbarch
*gdbarch
,
3915 const struct language_defn
*language
,
3916 void *cookie
, int argc
, struct value
**argv
)
3921 error (_("You must provide one argument for $_isvoid."));
3923 ret
= TYPE_CODE (value_type (argv
[0])) == TYPE_CODE_VOID
;
3925 return value_from_longest (builtin_type (gdbarch
)->builtin_int
, ret
);
3929 _initialize_values (void)
3931 add_cmd ("convenience", no_class
, show_convenience
, _("\
3932 Debugger convenience (\"$foo\") variables and functions.\n\
3933 Convenience variables are created when you assign them values;\n\
3934 thus, \"set $foo=1\" gives \"$foo\" the value 1. Values may be any type.\n\
3936 A few convenience variables are given values automatically:\n\
3937 \"$_\"holds the last address examined with \"x\" or \"info lines\",\n\
3938 \"$__\" holds the contents of the last address examined with \"x\"."
3941 Convenience functions are defined via the Python API."
3944 add_alias_cmd ("conv", "convenience", no_class
, 1, &showlist
);
3946 add_cmd ("values", no_set_class
, show_values
, _("\
3947 Elements of value history around item number IDX (or last ten)."),
3950 add_com ("init-if-undefined", class_vars
, init_if_undefined_command
, _("\
3951 Initialize a convenience variable if necessary.\n\
3952 init-if-undefined VARIABLE = EXPRESSION\n\
3953 Set an internal VARIABLE to the result of the EXPRESSION if it does not\n\
3954 exist or does not contain a value. The EXPRESSION is not evaluated if the\n\
3955 VARIABLE is already initialized."));
3957 add_prefix_cmd ("function", no_class
, function_command
, _("\
3958 Placeholder command for showing help on convenience functions."),
3959 &functionlist
, "function ", 0, &cmdlist
);
3961 add_internal_function ("_isvoid", _("\
3962 Check whether an expression is void.\n\
3963 Usage: $_isvoid (expression)\n\
3964 Return 1 if the expression is void, zero otherwise."),
3965 isvoid_internal_fn
, NULL
);