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c906108c 1/* Low level packing and unpacking of values for GDB, the GNU Debugger.
1bac305b 2
b811d2c2 3 Copyright (C) 1986-2020 Free Software Foundation, Inc.
c906108c 4
c5aa993b 5 This file is part of GDB.
c906108c 6
c5aa993b
JM
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
a9762ec7 9 the Free Software Foundation; either version 3 of the License, or
c5aa993b 10 (at your option) any later version.
c906108c 11
c5aa993b
JM
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.
c906108c 16
c5aa993b 17 You should have received a copy of the GNU General Public License
a9762ec7 18 along with this program. If not, see <http://www.gnu.org/licenses/>. */
c906108c
SS
19
20#include "defs.h"
e17c207e 21#include "arch-utils.h"
c906108c
SS
22#include "symtab.h"
23#include "gdbtypes.h"
24#include "value.h"
25#include "gdbcore.h"
c906108c
SS
26#include "command.h"
27#include "gdbcmd.h"
28#include "target.h"
29#include "language.h"
c906108c 30#include "demangle.h"
36160dc4 31#include "regcache.h"
fe898f56 32#include "block.h"
70100014 33#include "target-float.h"
bccdca4a 34#include "objfiles.h"
79a45b7d 35#include "valprint.h"
bc3b79fd 36#include "cli/cli-decode.h"
6dddc817 37#include "extension.h"
3bd0f5ef 38#include <ctype.h>
0914bcdb 39#include "tracepoint.h"
be335936 40#include "cp-abi.h"
a58e2656 41#include "user-regs.h"
325fac50 42#include <algorithm>
eb3ff9a5 43#include "completer.h"
268a13a5
TT
44#include "gdbsupport/selftest.h"
45#include "gdbsupport/array-view.h"
7f6aba03 46#include "cli/cli-style.h"
0914bcdb 47
bc3b79fd
TJB
48/* Definition of a user function. */
49struct internal_function
50{
51 /* The name of the function. It is a bit odd to have this in the
52 function itself -- the user might use a differently-named
53 convenience variable to hold the function. */
54 char *name;
55
56 /* The handler. */
57 internal_function_fn handler;
58
59 /* User data for the handler. */
60 void *cookie;
61};
62
4e07d55f
PA
63/* Defines an [OFFSET, OFFSET + LENGTH) range. */
64
65struct range
66{
67 /* Lowest offset in the range. */
6b850546 68 LONGEST offset;
4e07d55f
PA
69
70 /* Length of the range. */
6b850546 71 LONGEST length;
4e07d55f 72
0c7e6dd8
TT
73 /* Returns true if THIS is strictly less than OTHER, useful for
74 searching. We keep ranges sorted by offset and coalesce
75 overlapping and contiguous ranges, so this just compares the
76 starting offset. */
4e07d55f 77
0c7e6dd8
TT
78 bool operator< (const range &other) const
79 {
80 return offset < other.offset;
81 }
d5f4488f
SM
82
83 /* Returns true if THIS is equal to OTHER. */
84 bool operator== (const range &other) const
85 {
86 return offset == other.offset && length == other.length;
87 }
0c7e6dd8 88};
4e07d55f
PA
89
90/* Returns true if the ranges defined by [offset1, offset1+len1) and
91 [offset2, offset2+len2) overlap. */
92
93static int
6b850546
DT
94ranges_overlap (LONGEST offset1, LONGEST len1,
95 LONGEST offset2, LONGEST len2)
4e07d55f
PA
96{
97 ULONGEST h, l;
98
325fac50
PA
99 l = std::max (offset1, offset2);
100 h = std::min (offset1 + len1, offset2 + len2);
4e07d55f
PA
101 return (l < h);
102}
103
4e07d55f
PA
104/* Returns true if RANGES contains any range that overlaps [OFFSET,
105 OFFSET+LENGTH). */
106
107static int
0c7e6dd8
TT
108ranges_contain (const std::vector<range> &ranges, LONGEST offset,
109 LONGEST length)
4e07d55f 110{
0c7e6dd8 111 range what;
4e07d55f
PA
112
113 what.offset = offset;
114 what.length = length;
115
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.,
123
dda83cd7
SM
124 R
125 |---|
4e07d55f
PA
126 |---| |---| |------| ... |--|
127 0 1 2 N
128
129 I=1
130
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'
134 overlaps with R.
135
136 Then we need to check if the I range overlaps the I range itself.
137 E.g.,
138
dda83cd7
SM
139 R
140 |---|
4e07d55f
PA
141 |---| |---| |-------| ... |--|
142 0 1 2 N
143
144 I=1
145 */
146
4e07d55f 147
0c7e6dd8
TT
148 auto i = std::lower_bound (ranges.begin (), ranges.end (), what);
149
150 if (i > ranges.begin ())
4e07d55f 151 {
0c7e6dd8 152 const struct range &bef = *(i - 1);
4e07d55f 153
0c7e6dd8 154 if (ranges_overlap (bef.offset, bef.length, offset, length))
4e07d55f
PA
155 return 1;
156 }
157
0c7e6dd8 158 if (i < ranges.end ())
4e07d55f 159 {
0c7e6dd8 160 const struct range &r = *i;
4e07d55f 161
0c7e6dd8 162 if (ranges_overlap (r.offset, r.length, offset, length))
4e07d55f
PA
163 return 1;
164 }
165
166 return 0;
167}
168
bc3b79fd
TJB
169static struct cmd_list_element *functionlist;
170
87784a47
TT
171/* Note that the fields in this structure are arranged to save a bit
172 of memory. */
173
91294c83
AC
174struct value
175{
466ce3ae
TT
176 explicit value (struct type *type_)
177 : modifiable (1),
178 lazy (1),
179 initialized (1),
180 stack (0),
181 type (type_),
182 enclosing_type (type_)
183 {
466ce3ae
TT
184 }
185
186 ~value ()
187 {
466ce3ae
TT
188 if (VALUE_LVAL (this) == lval_computed)
189 {
190 const struct lval_funcs *funcs = location.computed.funcs;
191
192 if (funcs->free_closure)
193 funcs->free_closure (this);
194 }
195 else if (VALUE_LVAL (this) == lval_xcallable)
196 delete location.xm_worker;
466ce3ae
TT
197 }
198
199 DISABLE_COPY_AND_ASSIGN (value);
200
91294c83
AC
201 /* Type of value; either not an lval, or one of the various
202 different possible kinds of lval. */
466ce3ae 203 enum lval_type lval = not_lval;
91294c83
AC
204
205 /* Is it modifiable? Only relevant if lval != not_lval. */
87784a47
TT
206 unsigned int modifiable : 1;
207
208 /* If zero, contents of this value are in the contents field. If
209 nonzero, contents are in inferior. If the lval field is lval_memory,
210 the contents are in inferior memory at location.address plus offset.
211 The lval field may also be lval_register.
212
213 WARNING: This field is used by the code which handles watchpoints
214 (see breakpoint.c) to decide whether a particular value can be
215 watched by hardware watchpoints. If the lazy flag is set for
216 some member of a value chain, it is assumed that this member of
217 the chain doesn't need to be watched as part of watching the
218 value itself. This is how GDB avoids watching the entire struct
219 or array when the user wants to watch a single struct member or
220 array element. If you ever change the way lazy flag is set and
221 reset, be sure to consider this use as well! */
222 unsigned int lazy : 1;
223
87784a47
TT
224 /* If value is a variable, is it initialized or not. */
225 unsigned int initialized : 1;
226
227 /* If value is from the stack. If this is set, read_stack will be
228 used instead of read_memory to enable extra caching. */
229 unsigned int stack : 1;
91294c83
AC
230
231 /* Location of value (if lval). */
232 union
233 {
7dc54575 234 /* If lval == lval_memory, this is the address in the inferior */
91294c83
AC
235 CORE_ADDR address;
236
7dc54575
YQ
237 /*If lval == lval_register, the value is from a register. */
238 struct
239 {
240 /* Register number. */
241 int regnum;
242 /* Frame ID of "next" frame to which a register value is relative.
243 If the register value is found relative to frame F, then the
244 frame id of F->next will be stored in next_frame_id. */
245 struct frame_id next_frame_id;
246 } reg;
247
91294c83
AC
248 /* Pointer to internal variable. */
249 struct internalvar *internalvar;
5f5233d4 250
e81e7f5e
SC
251 /* Pointer to xmethod worker. */
252 struct xmethod_worker *xm_worker;
253
5f5233d4
PA
254 /* If lval == lval_computed, this is a set of function pointers
255 to use to access and describe the value, and a closure pointer
256 for them to use. */
257 struct
258 {
c8f2448a
JK
259 /* Functions to call. */
260 const struct lval_funcs *funcs;
261
262 /* Closure for those functions to use. */
263 void *closure;
5f5233d4 264 } computed;
41a883c8 265 } location {};
91294c83 266
3723fda8 267 /* Describes offset of a value within lval of a structure in target
7dc54575
YQ
268 addressable memory units. Note also the member embedded_offset
269 below. */
466ce3ae 270 LONGEST offset = 0;
91294c83
AC
271
272 /* Only used for bitfields; number of bits contained in them. */
466ce3ae 273 LONGEST bitsize = 0;
91294c83
AC
274
275 /* Only used for bitfields; position of start of field. For
d5a22e77
TT
276 little-endian targets, it is the position of the LSB. For
277 big-endian targets, it is the position of the MSB. */
466ce3ae 278 LONGEST bitpos = 0;
91294c83 279
87784a47
TT
280 /* The number of references to this value. When a value is created,
281 the value chain holds a reference, so REFERENCE_COUNT is 1. If
282 release_value is called, this value is removed from the chain but
283 the caller of release_value now has a reference to this value.
284 The caller must arrange for a call to value_free later. */
466ce3ae 285 int reference_count = 1;
87784a47 286
4ea48cc1
DJ
287 /* Only used for bitfields; the containing value. This allows a
288 single read from the target when displaying multiple
289 bitfields. */
2c8331b9 290 value_ref_ptr parent;
4ea48cc1 291
91294c83
AC
292 /* Type of the value. */
293 struct type *type;
294
295 /* If a value represents a C++ object, then the `type' field gives
296 the object's compile-time type. If the object actually belongs
297 to some class derived from `type', perhaps with other base
298 classes and additional members, then `type' is just a subobject
299 of the real thing, and the full object is probably larger than
300 `type' would suggest.
301
302 If `type' is a dynamic class (i.e. one with a vtable), then GDB
303 can actually determine the object's run-time type by looking at
304 the run-time type information in the vtable. When this
305 information is available, we may elect to read in the entire
306 object, for several reasons:
307
308 - When printing the value, the user would probably rather see the
309 full object, not just the limited portion apparent from the
310 compile-time type.
311
312 - If `type' has virtual base classes, then even printing `type'
313 alone may require reaching outside the `type' portion of the
314 object to wherever the virtual base class has been stored.
315
316 When we store the entire object, `enclosing_type' is the run-time
317 type -- the complete object -- and `embedded_offset' is the
3723fda8
SM
318 offset of `type' within that larger type, in target addressable memory
319 units. The value_contents() macro takes `embedded_offset' into account,
320 so most GDB code continues to see the `type' portion of the value, just
321 as the inferior would.
91294c83
AC
322
323 If `type' is a pointer to an object, then `enclosing_type' is a
324 pointer to the object's run-time type, and `pointed_to_offset' is
3723fda8
SM
325 the offset in target addressable memory units from the full object
326 to the pointed-to object -- that is, the value `embedded_offset' would
327 have if we followed the pointer and fetched the complete object.
328 (I don't really see the point. Why not just determine the
329 run-time type when you indirect, and avoid the special case? The
330 contents don't matter until you indirect anyway.)
91294c83
AC
331
332 If we're not doing anything fancy, `enclosing_type' is equal to
333 `type', and `embedded_offset' is zero, so everything works
334 normally. */
335 struct type *enclosing_type;
466ce3ae
TT
336 LONGEST embedded_offset = 0;
337 LONGEST pointed_to_offset = 0;
91294c83 338
3e3d7139
JG
339 /* Actual contents of the value. Target byte-order. NULL or not
340 valid if lazy is nonzero. */
14c88955 341 gdb::unique_xmalloc_ptr<gdb_byte> contents;
828d3400 342
4e07d55f
PA
343 /* Unavailable ranges in CONTENTS. We mark unavailable ranges,
344 rather than available, since the common and default case is for a
9a0dc9e3
PA
345 value to be available. This is filled in at value read time.
346 The unavailable ranges are tracked in bits. Note that a contents
347 bit that has been optimized out doesn't really exist in the
348 program, so it can't be marked unavailable either. */
0c7e6dd8 349 std::vector<range> unavailable;
9a0dc9e3
PA
350
351 /* Likewise, but for optimized out contents (a chunk of the value of
352 a variable that does not actually exist in the program). If LVAL
353 is lval_register, this is a register ($pc, $sp, etc., never a
354 program variable) that has not been saved in the frame. Not
355 saved registers and optimized-out program variables values are
356 treated pretty much the same, except not-saved registers have a
357 different string representation and related error strings. */
0c7e6dd8 358 std::vector<range> optimized_out;
91294c83
AC
359};
360
e512cdbd
SM
361/* See value.h. */
362
363struct gdbarch *
364get_value_arch (const struct value *value)
365{
366 return get_type_arch (value_type (value));
367}
368
4e07d55f 369int
6b850546 370value_bits_available (const struct value *value, LONGEST offset, LONGEST length)
4e07d55f
PA
371{
372 gdb_assert (!value->lazy);
373
374 return !ranges_contain (value->unavailable, offset, length);
375}
376
bdf22206 377int
6b850546
DT
378value_bytes_available (const struct value *value,
379 LONGEST offset, LONGEST length)
bdf22206
AB
380{
381 return value_bits_available (value,
382 offset * TARGET_CHAR_BIT,
383 length * TARGET_CHAR_BIT);
384}
385
9a0dc9e3
PA
386int
387value_bits_any_optimized_out (const struct value *value, int bit_offset, int bit_length)
388{
389 gdb_assert (!value->lazy);
390
391 return ranges_contain (value->optimized_out, bit_offset, bit_length);
392}
393
ec0a52e1
PA
394int
395value_entirely_available (struct value *value)
396{
397 /* We can only tell whether the whole value is available when we try
398 to read it. */
399 if (value->lazy)
400 value_fetch_lazy (value);
401
0c7e6dd8 402 if (value->unavailable.empty ())
ec0a52e1
PA
403 return 1;
404 return 0;
405}
406
9a0dc9e3
PA
407/* Returns true if VALUE is entirely covered by RANGES. If the value
408 is lazy, it'll be read now. Note that RANGE is a pointer to
409 pointer because reading the value might change *RANGE. */
410
411static int
412value_entirely_covered_by_range_vector (struct value *value,
0c7e6dd8 413 const std::vector<range> &ranges)
6211c335 414{
9a0dc9e3
PA
415 /* We can only tell whether the whole value is optimized out /
416 unavailable when we try to read it. */
6211c335
YQ
417 if (value->lazy)
418 value_fetch_lazy (value);
419
0c7e6dd8 420 if (ranges.size () == 1)
6211c335 421 {
0c7e6dd8 422 const struct range &t = ranges[0];
6211c335 423
0c7e6dd8
TT
424 if (t.offset == 0
425 && t.length == (TARGET_CHAR_BIT
426 * TYPE_LENGTH (value_enclosing_type (value))))
6211c335
YQ
427 return 1;
428 }
429
430 return 0;
431}
432
9a0dc9e3
PA
433int
434value_entirely_unavailable (struct value *value)
435{
0c7e6dd8 436 return value_entirely_covered_by_range_vector (value, value->unavailable);
9a0dc9e3
PA
437}
438
439int
440value_entirely_optimized_out (struct value *value)
441{
0c7e6dd8 442 return value_entirely_covered_by_range_vector (value, value->optimized_out);
9a0dc9e3
PA
443}
444
445/* Insert into the vector pointed to by VECTORP the bit range starting of
446 OFFSET bits, and extending for the next LENGTH bits. */
447
448static void
0c7e6dd8 449insert_into_bit_range_vector (std::vector<range> *vectorp,
6b850546 450 LONGEST offset, LONGEST length)
4e07d55f 451{
0c7e6dd8 452 range newr;
4e07d55f
PA
453
454 /* Insert the range sorted. If there's overlap or the new range
455 would be contiguous with an existing range, merge. */
456
457 newr.offset = offset;
458 newr.length = length;
459
460 /* Do a binary search for the position the given range would be
461 inserted if we only considered the starting OFFSET of ranges.
462 Call that position I. Since we also have LENGTH to care for
463 (this is a range afterall), we need to check if the _previous_
464 range overlaps the I range. E.g., calling R the new range:
465
466 #1 - overlaps with previous
467
468 R
469 |-...-|
470 |---| |---| |------| ... |--|
471 0 1 2 N
472
473 I=1
474
475 In the case #1 above, the binary search would return `I=1',
476 meaning, this OFFSET should be inserted at position 1, and the
477 current position 1 should be pushed further (and become 2). But,
478 note that `0' overlaps with R, so we want to merge them.
479
480 A similar consideration needs to be taken if the new range would
481 be contiguous with the previous range:
482
483 #2 - contiguous with previous
484
485 R
486 |-...-|
487 |--| |---| |------| ... |--|
488 0 1 2 N
489
490 I=1
491
492 If there's no overlap with the previous range, as in:
493
494 #3 - not overlapping and not contiguous
495
496 R
497 |-...-|
498 |--| |---| |------| ... |--|
499 0 1 2 N
500
501 I=1
502
503 or if I is 0:
504
505 #4 - R is the range with lowest offset
506
507 R
508 |-...-|
dda83cd7
SM
509 |--| |---| |------| ... |--|
510 0 1 2 N
4e07d55f
PA
511
512 I=0
513
514 ... we just push the new range to I.
515
516 All the 4 cases above need to consider that the new range may
517 also overlap several of the ranges that follow, or that R may be
518 contiguous with the following range, and merge. E.g.,
519
520 #5 - overlapping following ranges
521
522 R
523 |------------------------|
dda83cd7
SM
524 |--| |---| |------| ... |--|
525 0 1 2 N
4e07d55f
PA
526
527 I=0
528
529 or:
530
531 R
532 |-------|
533 |--| |---| |------| ... |--|
534 0 1 2 N
535
536 I=1
537
538 */
539
0c7e6dd8
TT
540 auto i = std::lower_bound (vectorp->begin (), vectorp->end (), newr);
541 if (i > vectorp->begin ())
4e07d55f 542 {
0c7e6dd8 543 struct range &bef = *(i - 1);
4e07d55f 544
0c7e6dd8 545 if (ranges_overlap (bef.offset, bef.length, offset, length))
4e07d55f
PA
546 {
547 /* #1 */
0c7e6dd8
TT
548 ULONGEST l = std::min (bef.offset, offset);
549 ULONGEST h = std::max (bef.offset + bef.length, offset + length);
4e07d55f 550
0c7e6dd8
TT
551 bef.offset = l;
552 bef.length = h - l;
4e07d55f
PA
553 i--;
554 }
0c7e6dd8 555 else if (offset == bef.offset + bef.length)
4e07d55f
PA
556 {
557 /* #2 */
0c7e6dd8 558 bef.length += length;
4e07d55f
PA
559 i--;
560 }
561 else
562 {
563 /* #3 */
0c7e6dd8 564 i = vectorp->insert (i, newr);
4e07d55f
PA
565 }
566 }
567 else
568 {
569 /* #4 */
0c7e6dd8 570 i = vectorp->insert (i, newr);
4e07d55f
PA
571 }
572
573 /* Check whether the ranges following the one we've just added or
574 touched can be folded in (#5 above). */
0c7e6dd8 575 if (i != vectorp->end () && i + 1 < vectorp->end ())
4e07d55f 576 {
4e07d55f 577 int removed = 0;
0c7e6dd8 578 auto next = i + 1;
4e07d55f
PA
579
580 /* Get the range we just touched. */
0c7e6dd8 581 struct range &t = *i;
4e07d55f
PA
582 removed = 0;
583
584 i = next;
0c7e6dd8
TT
585 for (; i < vectorp->end (); i++)
586 {
587 struct range &r = *i;
588 if (r.offset <= t.offset + t.length)
589 {
590 ULONGEST l, h;
591
592 l = std::min (t.offset, r.offset);
593 h = std::max (t.offset + t.length, r.offset + r.length);
594
595 t.offset = l;
596 t.length = h - l;
597
598 removed++;
599 }
600 else
601 {
602 /* If we couldn't merge this one, we won't be able to
603 merge following ones either, since the ranges are
604 always sorted by OFFSET. */
605 break;
606 }
607 }
4e07d55f
PA
608
609 if (removed != 0)
0c7e6dd8 610 vectorp->erase (next, next + removed);
4e07d55f
PA
611 }
612}
613
9a0dc9e3 614void
6b850546
DT
615mark_value_bits_unavailable (struct value *value,
616 LONGEST offset, LONGEST length)
9a0dc9e3
PA
617{
618 insert_into_bit_range_vector (&value->unavailable, offset, length);
619}
620
bdf22206 621void
6b850546
DT
622mark_value_bytes_unavailable (struct value *value,
623 LONGEST offset, LONGEST length)
bdf22206
AB
624{
625 mark_value_bits_unavailable (value,
626 offset * TARGET_CHAR_BIT,
627 length * TARGET_CHAR_BIT);
628}
629
c8c1c22f
PA
630/* Find the first range in RANGES that overlaps the range defined by
631 OFFSET and LENGTH, starting at element POS in the RANGES vector,
632 Returns the index into RANGES where such overlapping range was
633 found, or -1 if none was found. */
634
635static int
0c7e6dd8 636find_first_range_overlap (const std::vector<range> *ranges, int pos,
6b850546 637 LONGEST offset, LONGEST length)
c8c1c22f 638{
c8c1c22f
PA
639 int i;
640
0c7e6dd8
TT
641 for (i = pos; i < ranges->size (); i++)
642 {
643 const range &r = (*ranges)[i];
644 if (ranges_overlap (r.offset, r.length, offset, length))
645 return i;
646 }
c8c1c22f
PA
647
648 return -1;
649}
650
bdf22206
AB
651/* Compare LENGTH_BITS of memory at PTR1 + OFFSET1_BITS with the memory at
652 PTR2 + OFFSET2_BITS. Return 0 if the memory is the same, otherwise
653 return non-zero.
654
655 It must always be the case that:
656 OFFSET1_BITS % TARGET_CHAR_BIT == OFFSET2_BITS % TARGET_CHAR_BIT
657
658 It is assumed that memory can be accessed from:
659 PTR + (OFFSET_BITS / TARGET_CHAR_BIT)
660 to:
661 PTR + ((OFFSET_BITS + LENGTH_BITS + TARGET_CHAR_BIT - 1)
dda83cd7 662 / TARGET_CHAR_BIT) */
bdf22206
AB
663static int
664memcmp_with_bit_offsets (const gdb_byte *ptr1, size_t offset1_bits,
665 const gdb_byte *ptr2, size_t offset2_bits,
666 size_t length_bits)
667{
668 gdb_assert (offset1_bits % TARGET_CHAR_BIT
669 == offset2_bits % TARGET_CHAR_BIT);
670
671 if (offset1_bits % TARGET_CHAR_BIT != 0)
672 {
673 size_t bits;
674 gdb_byte mask, b1, b2;
675
676 /* The offset from the base pointers PTR1 and PTR2 is not a complete
677 number of bytes. A number of bits up to either the next exact
678 byte boundary, or LENGTH_BITS (which ever is sooner) will be
679 compared. */
680 bits = TARGET_CHAR_BIT - offset1_bits % TARGET_CHAR_BIT;
681 gdb_assert (bits < sizeof (mask) * TARGET_CHAR_BIT);
682 mask = (1 << bits) - 1;
683
684 if (length_bits < bits)
685 {
686 mask &= ~(gdb_byte) ((1 << (bits - length_bits)) - 1);
687 bits = length_bits;
688 }
689
690 /* Now load the two bytes and mask off the bits we care about. */
691 b1 = *(ptr1 + offset1_bits / TARGET_CHAR_BIT) & mask;
692 b2 = *(ptr2 + offset2_bits / TARGET_CHAR_BIT) & mask;
693
694 if (b1 != b2)
695 return 1;
696
697 /* Now update the length and offsets to take account of the bits
698 we've just compared. */
699 length_bits -= bits;
700 offset1_bits += bits;
701 offset2_bits += bits;
702 }
703
704 if (length_bits % TARGET_CHAR_BIT != 0)
705 {
706 size_t bits;
707 size_t o1, o2;
708 gdb_byte mask, b1, b2;
709
710 /* The length is not an exact number of bytes. After the previous
711 IF.. block then the offsets are byte aligned, or the
712 length is zero (in which case this code is not reached). Compare
713 a number of bits at the end of the region, starting from an exact
714 byte boundary. */
715 bits = length_bits % TARGET_CHAR_BIT;
716 o1 = offset1_bits + length_bits - bits;
717 o2 = offset2_bits + length_bits - bits;
718
719 gdb_assert (bits < sizeof (mask) * TARGET_CHAR_BIT);
720 mask = ((1 << bits) - 1) << (TARGET_CHAR_BIT - bits);
721
722 gdb_assert (o1 % TARGET_CHAR_BIT == 0);
723 gdb_assert (o2 % TARGET_CHAR_BIT == 0);
724
725 b1 = *(ptr1 + o1 / TARGET_CHAR_BIT) & mask;
726 b2 = *(ptr2 + o2 / TARGET_CHAR_BIT) & mask;
727
728 if (b1 != b2)
729 return 1;
730
731 length_bits -= bits;
732 }
733
734 if (length_bits > 0)
735 {
736 /* We've now taken care of any stray "bits" at the start, or end of
737 the region to compare, the remainder can be covered with a simple
738 memcmp. */
739 gdb_assert (offset1_bits % TARGET_CHAR_BIT == 0);
740 gdb_assert (offset2_bits % TARGET_CHAR_BIT == 0);
741 gdb_assert (length_bits % TARGET_CHAR_BIT == 0);
742
743 return memcmp (ptr1 + offset1_bits / TARGET_CHAR_BIT,
744 ptr2 + offset2_bits / TARGET_CHAR_BIT,
745 length_bits / TARGET_CHAR_BIT);
746 }
747
748 /* Length is zero, regions match. */
749 return 0;
750}
751
9a0dc9e3
PA
752/* Helper struct for find_first_range_overlap_and_match and
753 value_contents_bits_eq. Keep track of which slot of a given ranges
754 vector have we last looked at. */
bdf22206 755
9a0dc9e3
PA
756struct ranges_and_idx
757{
758 /* The ranges. */
0c7e6dd8 759 const std::vector<range> *ranges;
9a0dc9e3
PA
760
761 /* The range we've last found in RANGES. Given ranges are sorted,
762 we can start the next lookup here. */
763 int idx;
764};
765
766/* Helper function for value_contents_bits_eq. Compare LENGTH bits of
767 RP1's ranges starting at OFFSET1 bits with LENGTH bits of RP2's
768 ranges starting at OFFSET2 bits. Return true if the ranges match
769 and fill in *L and *H with the overlapping window relative to
770 (both) OFFSET1 or OFFSET2. */
bdf22206
AB
771
772static int
9a0dc9e3
PA
773find_first_range_overlap_and_match (struct ranges_and_idx *rp1,
774 struct ranges_and_idx *rp2,
6b850546
DT
775 LONGEST offset1, LONGEST offset2,
776 LONGEST length, ULONGEST *l, ULONGEST *h)
c8c1c22f 777{
9a0dc9e3
PA
778 rp1->idx = find_first_range_overlap (rp1->ranges, rp1->idx,
779 offset1, length);
780 rp2->idx = find_first_range_overlap (rp2->ranges, rp2->idx,
781 offset2, length);
c8c1c22f 782
9a0dc9e3
PA
783 if (rp1->idx == -1 && rp2->idx == -1)
784 {
785 *l = length;
786 *h = length;
787 return 1;
788 }
789 else if (rp1->idx == -1 || rp2->idx == -1)
790 return 0;
791 else
c8c1c22f 792 {
0c7e6dd8 793 const range *r1, *r2;
c8c1c22f
PA
794 ULONGEST l1, h1;
795 ULONGEST l2, h2;
796
0c7e6dd8
TT
797 r1 = &(*rp1->ranges)[rp1->idx];
798 r2 = &(*rp2->ranges)[rp2->idx];
c8c1c22f
PA
799
800 /* Get the unavailable windows intersected by the incoming
801 ranges. The first and last ranges that overlap the argument
802 range may be wider than said incoming arguments ranges. */
325fac50
PA
803 l1 = std::max (offset1, r1->offset);
804 h1 = std::min (offset1 + length, r1->offset + r1->length);
c8c1c22f 805
325fac50
PA
806 l2 = std::max (offset2, r2->offset);
807 h2 = std::min (offset2 + length, offset2 + r2->length);
c8c1c22f
PA
808
809 /* Make them relative to the respective start offsets, so we can
810 compare them for equality. */
811 l1 -= offset1;
812 h1 -= offset1;
813
814 l2 -= offset2;
815 h2 -= offset2;
816
9a0dc9e3 817 /* Different ranges, no match. */
c8c1c22f
PA
818 if (l1 != l2 || h1 != h2)
819 return 0;
820
9a0dc9e3
PA
821 *h = h1;
822 *l = l1;
823 return 1;
824 }
825}
826
827/* Helper function for value_contents_eq. The only difference is that
828 this function is bit rather than byte based.
829
830 Compare LENGTH bits of VAL1's contents starting at OFFSET1 bits
831 with LENGTH bits of VAL2's contents starting at OFFSET2 bits.
832 Return true if the available bits match. */
833
98ead37e 834static bool
9a0dc9e3
PA
835value_contents_bits_eq (const struct value *val1, int offset1,
836 const struct value *val2, int offset2,
837 int length)
838{
839 /* Each array element corresponds to a ranges source (unavailable,
840 optimized out). '1' is for VAL1, '2' for VAL2. */
841 struct ranges_and_idx rp1[2], rp2[2];
842
843 /* See function description in value.h. */
844 gdb_assert (!val1->lazy && !val2->lazy);
845
846 /* We shouldn't be trying to compare past the end of the values. */
847 gdb_assert (offset1 + length
848 <= TYPE_LENGTH (val1->enclosing_type) * TARGET_CHAR_BIT);
849 gdb_assert (offset2 + length
850 <= TYPE_LENGTH (val2->enclosing_type) * TARGET_CHAR_BIT);
851
852 memset (&rp1, 0, sizeof (rp1));
853 memset (&rp2, 0, sizeof (rp2));
0c7e6dd8
TT
854 rp1[0].ranges = &val1->unavailable;
855 rp2[0].ranges = &val2->unavailable;
856 rp1[1].ranges = &val1->optimized_out;
857 rp2[1].ranges = &val2->optimized_out;
9a0dc9e3
PA
858
859 while (length > 0)
860 {
000339af 861 ULONGEST l = 0, h = 0; /* init for gcc -Wall */
9a0dc9e3
PA
862 int i;
863
864 for (i = 0; i < 2; i++)
865 {
866 ULONGEST l_tmp, h_tmp;
867
868 /* The contents only match equal if the invalid/unavailable
869 contents ranges match as well. */
870 if (!find_first_range_overlap_and_match (&rp1[i], &rp2[i],
871 offset1, offset2, length,
872 &l_tmp, &h_tmp))
98ead37e 873 return false;
9a0dc9e3
PA
874
875 /* We're interested in the lowest/first range found. */
876 if (i == 0 || l_tmp < l)
877 {
878 l = l_tmp;
879 h = h_tmp;
880 }
881 }
882
883 /* Compare the available/valid contents. */
14c88955
TT
884 if (memcmp_with_bit_offsets (val1->contents.get (), offset1,
885 val2->contents.get (), offset2, l) != 0)
98ead37e 886 return false;
c8c1c22f 887
9a0dc9e3
PA
888 length -= h;
889 offset1 += h;
890 offset2 += h;
c8c1c22f
PA
891 }
892
98ead37e 893 return true;
c8c1c22f
PA
894}
895
98ead37e 896bool
6b850546
DT
897value_contents_eq (const struct value *val1, LONGEST offset1,
898 const struct value *val2, LONGEST offset2,
899 LONGEST length)
bdf22206 900{
9a0dc9e3
PA
901 return value_contents_bits_eq (val1, offset1 * TARGET_CHAR_BIT,
902 val2, offset2 * TARGET_CHAR_BIT,
903 length * TARGET_CHAR_BIT);
bdf22206
AB
904}
905
c906108c 906
4d0266a0
TT
907/* The value-history records all the values printed by print commands
908 during this session. */
c906108c 909
4d0266a0 910static std::vector<value_ref_ptr> value_history;
bc3b79fd 911
c906108c
SS
912\f
913/* List of all value objects currently allocated
914 (except for those released by calls to release_value)
915 This is so they can be freed after each command. */
916
062d818d 917static std::vector<value_ref_ptr> all_values;
c906108c 918
3e3d7139
JG
919/* Allocate a lazy value for type TYPE. Its actual content is
920 "lazily" allocated too: the content field of the return value is
921 NULL; it will be allocated when it is fetched from the target. */
c906108c 922
f23631e4 923struct value *
3e3d7139 924allocate_value_lazy (struct type *type)
c906108c 925{
f23631e4 926 struct value *val;
c54eabfa
JK
927
928 /* Call check_typedef on our type to make sure that, if TYPE
929 is a TYPE_CODE_TYPEDEF, its length is set to the length
930 of the target type instead of zero. However, we do not
931 replace the typedef type by the target type, because we want
932 to keep the typedef in order to be able to set the VAL's type
933 description correctly. */
934 check_typedef (type);
c906108c 935
466ce3ae 936 val = new struct value (type);
828d3400
DJ
937
938 /* Values start out on the all_values chain. */
062d818d 939 all_values.emplace_back (val);
828d3400 940
c906108c
SS
941 return val;
942}
943
5fdf6324
AB
944/* The maximum size, in bytes, that GDB will try to allocate for a value.
945 The initial value of 64k was not selected for any specific reason, it is
946 just a reasonable starting point. */
947
948static int max_value_size = 65536; /* 64k bytes */
949
950/* It is critical that the MAX_VALUE_SIZE is at least as big as the size of
951 LONGEST, otherwise GDB will not be able to parse integer values from the
952 CLI; for example if the MAX_VALUE_SIZE could be set to 1 then GDB would
953 be unable to parse "set max-value-size 2".
954
955 As we want a consistent GDB experience across hosts with different sizes
956 of LONGEST, this arbitrary minimum value was selected, so long as this
957 is bigger than LONGEST on all GDB supported hosts we're fine. */
958
959#define MIN_VALUE_FOR_MAX_VALUE_SIZE 16
960gdb_static_assert (sizeof (LONGEST) <= MIN_VALUE_FOR_MAX_VALUE_SIZE);
961
962/* Implement the "set max-value-size" command. */
963
964static void
eb4c3f4a 965set_max_value_size (const char *args, int from_tty,
5fdf6324
AB
966 struct cmd_list_element *c)
967{
968 gdb_assert (max_value_size == -1 || max_value_size >= 0);
969
970 if (max_value_size > -1 && max_value_size < MIN_VALUE_FOR_MAX_VALUE_SIZE)
971 {
972 max_value_size = MIN_VALUE_FOR_MAX_VALUE_SIZE;
973 error (_("max-value-size set too low, increasing to %d bytes"),
974 max_value_size);
975 }
976}
977
978/* Implement the "show max-value-size" command. */
979
980static void
981show_max_value_size (struct ui_file *file, int from_tty,
982 struct cmd_list_element *c, const char *value)
983{
984 if (max_value_size == -1)
985 fprintf_filtered (file, _("Maximum value size is unlimited.\n"));
986 else
987 fprintf_filtered (file, _("Maximum value size is %d bytes.\n"),
988 max_value_size);
989}
990
991/* Called before we attempt to allocate or reallocate a buffer for the
992 contents of a value. TYPE is the type of the value for which we are
993 allocating the buffer. If the buffer is too large (based on the user
994 controllable setting) then throw an error. If this function returns
995 then we should attempt to allocate the buffer. */
996
997static void
998check_type_length_before_alloc (const struct type *type)
999{
6d8a0a5e 1000 ULONGEST length = TYPE_LENGTH (type);
5fdf6324
AB
1001
1002 if (max_value_size > -1 && length > max_value_size)
1003 {
7d93a1e0 1004 if (type->name () != NULL)
6d8a0a5e
LM
1005 error (_("value of type `%s' requires %s bytes, which is more "
1006 "than max-value-size"), type->name (), pulongest (length));
5fdf6324 1007 else
6d8a0a5e
LM
1008 error (_("value requires %s bytes, which is more than "
1009 "max-value-size"), pulongest (length));
5fdf6324
AB
1010 }
1011}
1012
3e3d7139
JG
1013/* Allocate the contents of VAL if it has not been allocated yet. */
1014
548b762d 1015static void
3e3d7139
JG
1016allocate_value_contents (struct value *val)
1017{
1018 if (!val->contents)
5fdf6324
AB
1019 {
1020 check_type_length_before_alloc (val->enclosing_type);
14c88955
TT
1021 val->contents.reset
1022 ((gdb_byte *) xzalloc (TYPE_LENGTH (val->enclosing_type)));
5fdf6324 1023 }
3e3d7139
JG
1024}
1025
1026/* Allocate a value and its contents for type TYPE. */
1027
1028struct value *
1029allocate_value (struct type *type)
1030{
1031 struct value *val = allocate_value_lazy (type);
a109c7c1 1032
3e3d7139
JG
1033 allocate_value_contents (val);
1034 val->lazy = 0;
1035 return val;
1036}
1037
c906108c 1038/* Allocate a value that has the correct length
938f5214 1039 for COUNT repetitions of type TYPE. */
c906108c 1040
f23631e4 1041struct value *
fba45db2 1042allocate_repeat_value (struct type *type, int count)
c906108c 1043{
22c12a6c
AB
1044 /* Despite the fact that we are really creating an array of TYPE here, we
1045 use the string lower bound as the array lower bound. This seems to
1046 work fine for now. */
1047 int low_bound = current_language->string_lower_bound ();
c906108c
SS
1048 /* FIXME-type-allocation: need a way to free this type when we are
1049 done with it. */
e3506a9f
UW
1050 struct type *array_type
1051 = lookup_array_range_type (type, low_bound, count + low_bound - 1);
a109c7c1 1052
e3506a9f 1053 return allocate_value (array_type);
c906108c
SS
1054}
1055
5f5233d4
PA
1056struct value *
1057allocate_computed_value (struct type *type,
dda83cd7
SM
1058 const struct lval_funcs *funcs,
1059 void *closure)
5f5233d4 1060{
41e8491f 1061 struct value *v = allocate_value_lazy (type);
a109c7c1 1062
5f5233d4
PA
1063 VALUE_LVAL (v) = lval_computed;
1064 v->location.computed.funcs = funcs;
1065 v->location.computed.closure = closure;
5f5233d4
PA
1066
1067 return v;
1068}
1069
a7035dbb
JK
1070/* Allocate NOT_LVAL value for type TYPE being OPTIMIZED_OUT. */
1071
1072struct value *
1073allocate_optimized_out_value (struct type *type)
1074{
1075 struct value *retval = allocate_value_lazy (type);
1076
9a0dc9e3
PA
1077 mark_value_bytes_optimized_out (retval, 0, TYPE_LENGTH (type));
1078 set_value_lazy (retval, 0);
a7035dbb
JK
1079 return retval;
1080}
1081
df407dfe
AC
1082/* Accessor methods. */
1083
1084struct type *
0e03807e 1085value_type (const struct value *value)
df407dfe
AC
1086{
1087 return value->type;
1088}
04624583
AC
1089void
1090deprecated_set_value_type (struct value *value, struct type *type)
1091{
1092 value->type = type;
1093}
df407dfe 1094
6b850546 1095LONGEST
0e03807e 1096value_offset (const struct value *value)
df407dfe
AC
1097{
1098 return value->offset;
1099}
f5cf64a7 1100void
6b850546 1101set_value_offset (struct value *value, LONGEST offset)
f5cf64a7
AC
1102{
1103 value->offset = offset;
1104}
df407dfe 1105
6b850546 1106LONGEST
0e03807e 1107value_bitpos (const struct value *value)
df407dfe
AC
1108{
1109 return value->bitpos;
1110}
9bbda503 1111void
6b850546 1112set_value_bitpos (struct value *value, LONGEST bit)
9bbda503
AC
1113{
1114 value->bitpos = bit;
1115}
df407dfe 1116
6b850546 1117LONGEST
0e03807e 1118value_bitsize (const struct value *value)
df407dfe
AC
1119{
1120 return value->bitsize;
1121}
9bbda503 1122void
6b850546 1123set_value_bitsize (struct value *value, LONGEST bit)
9bbda503
AC
1124{
1125 value->bitsize = bit;
1126}
df407dfe 1127
4ea48cc1 1128struct value *
4bf7b526 1129value_parent (const struct value *value)
4ea48cc1 1130{
2c8331b9 1131 return value->parent.get ();
4ea48cc1
DJ
1132}
1133
53ba8333
JB
1134/* See value.h. */
1135
1136void
1137set_value_parent (struct value *value, struct value *parent)
1138{
bbfa6f00 1139 value->parent = value_ref_ptr::new_reference (parent);
53ba8333
JB
1140}
1141
fc1a4b47 1142gdb_byte *
990a07ab
AC
1143value_contents_raw (struct value *value)
1144{
3ae385af
SM
1145 struct gdbarch *arch = get_value_arch (value);
1146 int unit_size = gdbarch_addressable_memory_unit_size (arch);
1147
3e3d7139 1148 allocate_value_contents (value);
14c88955 1149 return value->contents.get () + value->embedded_offset * unit_size;
990a07ab
AC
1150}
1151
fc1a4b47 1152gdb_byte *
990a07ab
AC
1153value_contents_all_raw (struct value *value)
1154{
3e3d7139 1155 allocate_value_contents (value);
14c88955 1156 return value->contents.get ();
990a07ab
AC
1157}
1158
4754a64e 1159struct type *
4bf7b526 1160value_enclosing_type (const struct value *value)
4754a64e
AC
1161{
1162 return value->enclosing_type;
1163}
1164
8264ba82
AG
1165/* Look at value.h for description. */
1166
1167struct type *
1168value_actual_type (struct value *value, int resolve_simple_types,
1169 int *real_type_found)
1170{
1171 struct value_print_options opts;
8264ba82
AG
1172 struct type *result;
1173
1174 get_user_print_options (&opts);
1175
1176 if (real_type_found)
1177 *real_type_found = 0;
1178 result = value_type (value);
1179 if (opts.objectprint)
1180 {
5e34c6c3
LM
1181 /* If result's target type is TYPE_CODE_STRUCT, proceed to
1182 fetch its rtti type. */
78134374
SM
1183 if ((result->code () == TYPE_CODE_PTR || TYPE_IS_REFERENCE (result))
1184 && (check_typedef (TYPE_TARGET_TYPE (result))->code ()
1185 == TYPE_CODE_STRUCT)
ecf2e90c 1186 && !value_optimized_out (value))
dda83cd7
SM
1187 {
1188 struct type *real_type;
1189
1190 real_type = value_rtti_indirect_type (value, NULL, NULL, NULL);
1191 if (real_type)
1192 {
1193 if (real_type_found)
1194 *real_type_found = 1;
1195 result = real_type;
1196 }
1197 }
8264ba82 1198 else if (resolve_simple_types)
dda83cd7
SM
1199 {
1200 if (real_type_found)
1201 *real_type_found = 1;
1202 result = value_enclosing_type (value);
1203 }
8264ba82
AG
1204 }
1205
1206 return result;
1207}
1208
901461f8
PA
1209void
1210error_value_optimized_out (void)
1211{
1212 error (_("value has been optimized out"));
1213}
1214
0e03807e 1215static void
4e07d55f 1216require_not_optimized_out (const struct value *value)
0e03807e 1217{
0c7e6dd8 1218 if (!value->optimized_out.empty ())
901461f8
PA
1219 {
1220 if (value->lval == lval_register)
1221 error (_("register has not been saved in frame"));
1222 else
1223 error_value_optimized_out ();
1224 }
0e03807e
TT
1225}
1226
4e07d55f
PA
1227static void
1228require_available (const struct value *value)
1229{
0c7e6dd8 1230 if (!value->unavailable.empty ())
8af8e3bc 1231 throw_error (NOT_AVAILABLE_ERROR, _("value is not available"));
4e07d55f
PA
1232}
1233
fc1a4b47 1234const gdb_byte *
0e03807e 1235value_contents_for_printing (struct value *value)
46615f07
AC
1236{
1237 if (value->lazy)
1238 value_fetch_lazy (value);
14c88955 1239 return value->contents.get ();
46615f07
AC
1240}
1241
de4127a3
PA
1242const gdb_byte *
1243value_contents_for_printing_const (const struct value *value)
1244{
1245 gdb_assert (!value->lazy);
14c88955 1246 return value->contents.get ();
de4127a3
PA
1247}
1248
0e03807e
TT
1249const gdb_byte *
1250value_contents_all (struct value *value)
1251{
1252 const gdb_byte *result = value_contents_for_printing (value);
1253 require_not_optimized_out (value);
4e07d55f 1254 require_available (value);
0e03807e
TT
1255 return result;
1256}
1257
9a0dc9e3
PA
1258/* Copy ranges in SRC_RANGE that overlap [SRC_BIT_OFFSET,
1259 SRC_BIT_OFFSET+BIT_LENGTH) ranges into *DST_RANGE, adjusted. */
1260
1261static void
0c7e6dd8
TT
1262ranges_copy_adjusted (std::vector<range> *dst_range, int dst_bit_offset,
1263 const std::vector<range> &src_range, int src_bit_offset,
9a0dc9e3
PA
1264 int bit_length)
1265{
0c7e6dd8 1266 for (const range &r : src_range)
9a0dc9e3
PA
1267 {
1268 ULONGEST h, l;
1269
0c7e6dd8
TT
1270 l = std::max (r.offset, (LONGEST) src_bit_offset);
1271 h = std::min (r.offset + r.length,
325fac50 1272 (LONGEST) src_bit_offset + bit_length);
9a0dc9e3
PA
1273
1274 if (l < h)
1275 insert_into_bit_range_vector (dst_range,
1276 dst_bit_offset + (l - src_bit_offset),
1277 h - l);
1278 }
1279}
1280
4875ffdb
PA
1281/* Copy the ranges metadata in SRC that overlaps [SRC_BIT_OFFSET,
1282 SRC_BIT_OFFSET+BIT_LENGTH) into DST, adjusted. */
1283
1284static void
1285value_ranges_copy_adjusted (struct value *dst, int dst_bit_offset,
1286 const struct value *src, int src_bit_offset,
1287 int bit_length)
1288{
1289 ranges_copy_adjusted (&dst->unavailable, dst_bit_offset,
1290 src->unavailable, src_bit_offset,
1291 bit_length);
1292 ranges_copy_adjusted (&dst->optimized_out, dst_bit_offset,
1293 src->optimized_out, src_bit_offset,
1294 bit_length);
1295}
1296
3ae385af 1297/* Copy LENGTH target addressable memory units of SRC value's (all) contents
29976f3f
PA
1298 (value_contents_all) starting at SRC_OFFSET, into DST value's (all)
1299 contents, starting at DST_OFFSET. If unavailable contents are
1300 being copied from SRC, the corresponding DST contents are marked
1301 unavailable accordingly. Neither DST nor SRC may be lazy
1302 values.
1303
1304 It is assumed the contents of DST in the [DST_OFFSET,
1305 DST_OFFSET+LENGTH) range are wholly available. */
39d37385
PA
1306
1307void
6b850546
DT
1308value_contents_copy_raw (struct value *dst, LONGEST dst_offset,
1309 struct value *src, LONGEST src_offset, LONGEST length)
39d37385 1310{
6b850546 1311 LONGEST src_bit_offset, dst_bit_offset, bit_length;
3ae385af
SM
1312 struct gdbarch *arch = get_value_arch (src);
1313 int unit_size = gdbarch_addressable_memory_unit_size (arch);
39d37385
PA
1314
1315 /* A lazy DST would make that this copy operation useless, since as
1316 soon as DST's contents were un-lazied (by a later value_contents
1317 call, say), the contents would be overwritten. A lazy SRC would
1318 mean we'd be copying garbage. */
1319 gdb_assert (!dst->lazy && !src->lazy);
1320
29976f3f
PA
1321 /* The overwritten DST range gets unavailability ORed in, not
1322 replaced. Make sure to remember to implement replacing if it
1323 turns out actually necessary. */
1324 gdb_assert (value_bytes_available (dst, dst_offset, length));
9a0dc9e3
PA
1325 gdb_assert (!value_bits_any_optimized_out (dst,
1326 TARGET_CHAR_BIT * dst_offset,
1327 TARGET_CHAR_BIT * length));
29976f3f 1328
39d37385 1329 /* Copy the data. */
3ae385af
SM
1330 memcpy (value_contents_all_raw (dst) + dst_offset * unit_size,
1331 value_contents_all_raw (src) + src_offset * unit_size,
1332 length * unit_size);
39d37385
PA
1333
1334 /* Copy the meta-data, adjusted. */
3ae385af
SM
1335 src_bit_offset = src_offset * unit_size * HOST_CHAR_BIT;
1336 dst_bit_offset = dst_offset * unit_size * HOST_CHAR_BIT;
1337 bit_length = length * unit_size * HOST_CHAR_BIT;
39d37385 1338
4875ffdb
PA
1339 value_ranges_copy_adjusted (dst, dst_bit_offset,
1340 src, src_bit_offset,
1341 bit_length);
39d37385
PA
1342}
1343
29976f3f
PA
1344/* Copy LENGTH bytes of SRC value's (all) contents
1345 (value_contents_all) starting at SRC_OFFSET byte, into DST value's
1346 (all) contents, starting at DST_OFFSET. If unavailable contents
1347 are being copied from SRC, the corresponding DST contents are
1348 marked unavailable accordingly. DST must not be lazy. If SRC is
9a0dc9e3 1349 lazy, it will be fetched now.
29976f3f
PA
1350
1351 It is assumed the contents of DST in the [DST_OFFSET,
1352 DST_OFFSET+LENGTH) range are wholly available. */
39d37385
PA
1353
1354void
6b850546
DT
1355value_contents_copy (struct value *dst, LONGEST dst_offset,
1356 struct value *src, LONGEST src_offset, LONGEST length)
39d37385 1357{
39d37385
PA
1358 if (src->lazy)
1359 value_fetch_lazy (src);
1360
1361 value_contents_copy_raw (dst, dst_offset, src, src_offset, length);
1362}
1363
d69fe07e 1364int
4bf7b526 1365value_lazy (const struct value *value)
d69fe07e
AC
1366{
1367 return value->lazy;
1368}
1369
dfa52d88
AC
1370void
1371set_value_lazy (struct value *value, int val)
1372{
1373 value->lazy = val;
1374}
1375
4e5d721f 1376int
4bf7b526 1377value_stack (const struct value *value)
4e5d721f
DE
1378{
1379 return value->stack;
1380}
1381
1382void
1383set_value_stack (struct value *value, int val)
1384{
1385 value->stack = val;
1386}
1387
fc1a4b47 1388const gdb_byte *
0fd88904
AC
1389value_contents (struct value *value)
1390{
0e03807e
TT
1391 const gdb_byte *result = value_contents_writeable (value);
1392 require_not_optimized_out (value);
4e07d55f 1393 require_available (value);
0e03807e 1394 return result;
0fd88904
AC
1395}
1396
fc1a4b47 1397gdb_byte *
0fd88904
AC
1398value_contents_writeable (struct value *value)
1399{
1400 if (value->lazy)
1401 value_fetch_lazy (value);
fc0c53a0 1402 return value_contents_raw (value);
0fd88904
AC
1403}
1404
feb13ab0
AC
1405int
1406value_optimized_out (struct value *value)
1407{
691a26f5
AB
1408 /* We can only know if a value is optimized out once we have tried to
1409 fetch it. */
0c7e6dd8 1410 if (value->optimized_out.empty () && value->lazy)
ecf2e90c 1411 {
a70b8144 1412 try
ecf2e90c
DB
1413 {
1414 value_fetch_lazy (value);
1415 }
230d2906 1416 catch (const gdb_exception_error &ex)
ecf2e90c 1417 {
6d7aa592
PA
1418 switch (ex.error)
1419 {
1420 case MEMORY_ERROR:
1421 case OPTIMIZED_OUT_ERROR:
1422 case NOT_AVAILABLE_ERROR:
1423 /* These can normally happen when we try to access an
1424 optimized out or unavailable register, either in a
1425 physical register or spilled to memory. */
1426 break;
1427 default:
1428 throw;
1429 }
ecf2e90c 1430 }
ecf2e90c 1431 }
691a26f5 1432
0c7e6dd8 1433 return !value->optimized_out.empty ();
feb13ab0
AC
1434}
1435
9a0dc9e3
PA
1436/* Mark contents of VALUE as optimized out, starting at OFFSET bytes, and
1437 the following LENGTH bytes. */
eca07816 1438
feb13ab0 1439void
9a0dc9e3 1440mark_value_bytes_optimized_out (struct value *value, int offset, int length)
feb13ab0 1441{
9a0dc9e3
PA
1442 mark_value_bits_optimized_out (value,
1443 offset * TARGET_CHAR_BIT,
1444 length * TARGET_CHAR_BIT);
feb13ab0 1445}
13c3b5f5 1446
9a0dc9e3 1447/* See value.h. */
0e03807e 1448
9a0dc9e3 1449void
6b850546
DT
1450mark_value_bits_optimized_out (struct value *value,
1451 LONGEST offset, LONGEST length)
0e03807e 1452{
9a0dc9e3 1453 insert_into_bit_range_vector (&value->optimized_out, offset, length);
0e03807e
TT
1454}
1455
8cf6f0b1
TT
1456int
1457value_bits_synthetic_pointer (const struct value *value,
6b850546 1458 LONGEST offset, LONGEST length)
8cf6f0b1 1459{
e7303042 1460 if (value->lval != lval_computed
8cf6f0b1
TT
1461 || !value->location.computed.funcs->check_synthetic_pointer)
1462 return 0;
1463 return value->location.computed.funcs->check_synthetic_pointer (value,
1464 offset,
1465 length);
1466}
1467
6b850546 1468LONGEST
4bf7b526 1469value_embedded_offset (const struct value *value)
13c3b5f5
AC
1470{
1471 return value->embedded_offset;
1472}
1473
1474void
6b850546 1475set_value_embedded_offset (struct value *value, LONGEST val)
13c3b5f5
AC
1476{
1477 value->embedded_offset = val;
1478}
b44d461b 1479
6b850546 1480LONGEST
4bf7b526 1481value_pointed_to_offset (const struct value *value)
b44d461b
AC
1482{
1483 return value->pointed_to_offset;
1484}
1485
1486void
6b850546 1487set_value_pointed_to_offset (struct value *value, LONGEST val)
b44d461b
AC
1488{
1489 value->pointed_to_offset = val;
1490}
13bb5560 1491
c8f2448a 1492const struct lval_funcs *
a471c594 1493value_computed_funcs (const struct value *v)
5f5233d4 1494{
a471c594 1495 gdb_assert (value_lval_const (v) == lval_computed);
5f5233d4
PA
1496
1497 return v->location.computed.funcs;
1498}
1499
1500void *
0e03807e 1501value_computed_closure (const struct value *v)
5f5233d4 1502{
0e03807e 1503 gdb_assert (v->lval == lval_computed);
5f5233d4
PA
1504
1505 return v->location.computed.closure;
1506}
1507
13bb5560
AC
1508enum lval_type *
1509deprecated_value_lval_hack (struct value *value)
1510{
1511 return &value->lval;
1512}
1513
a471c594
JK
1514enum lval_type
1515value_lval_const (const struct value *value)
1516{
1517 return value->lval;
1518}
1519
42ae5230 1520CORE_ADDR
de4127a3 1521value_address (const struct value *value)
42ae5230 1522{
1a088441 1523 if (value->lval != lval_memory)
42ae5230 1524 return 0;
53ba8333 1525 if (value->parent != NULL)
2c8331b9 1526 return value_address (value->parent.get ()) + value->offset;
9920b434
BH
1527 if (NULL != TYPE_DATA_LOCATION (value_type (value)))
1528 {
1529 gdb_assert (PROP_CONST == TYPE_DATA_LOCATION_KIND (value_type (value)));
1530 return TYPE_DATA_LOCATION_ADDR (value_type (value));
1531 }
1532
1533 return value->location.address + value->offset;
42ae5230
TT
1534}
1535
1536CORE_ADDR
4bf7b526 1537value_raw_address (const struct value *value)
42ae5230 1538{
1a088441 1539 if (value->lval != lval_memory)
42ae5230
TT
1540 return 0;
1541 return value->location.address;
1542}
1543
1544void
1545set_value_address (struct value *value, CORE_ADDR addr)
13bb5560 1546{
1a088441 1547 gdb_assert (value->lval == lval_memory);
42ae5230 1548 value->location.address = addr;
13bb5560
AC
1549}
1550
1551struct internalvar **
1552deprecated_value_internalvar_hack (struct value *value)
1553{
1554 return &value->location.internalvar;
1555}
1556
1557struct frame_id *
41b56feb 1558deprecated_value_next_frame_id_hack (struct value *value)
13bb5560 1559{
7c2ba67e 1560 gdb_assert (value->lval == lval_register);
7dc54575 1561 return &value->location.reg.next_frame_id;
13bb5560
AC
1562}
1563
7dc54575 1564int *
13bb5560
AC
1565deprecated_value_regnum_hack (struct value *value)
1566{
7c2ba67e 1567 gdb_assert (value->lval == lval_register);
7dc54575 1568 return &value->location.reg.regnum;
13bb5560 1569}
88e3b34b
AC
1570
1571int
4bf7b526 1572deprecated_value_modifiable (const struct value *value)
88e3b34b
AC
1573{
1574 return value->modifiable;
1575}
990a07ab 1576\f
c906108c
SS
1577/* Return a mark in the value chain. All values allocated after the
1578 mark is obtained (except for those released) are subject to being freed
1579 if a subsequent value_free_to_mark is passed the mark. */
f23631e4 1580struct value *
fba45db2 1581value_mark (void)
c906108c 1582{
062d818d
TT
1583 if (all_values.empty ())
1584 return nullptr;
1585 return all_values.back ().get ();
c906108c
SS
1586}
1587
bbfa6f00 1588/* See value.h. */
828d3400 1589
bbfa6f00 1590void
828d3400
DJ
1591value_incref (struct value *val)
1592{
1593 val->reference_count++;
1594}
1595
1596/* Release a reference to VAL, which was acquired with value_incref.
1597 This function is also called to deallocate values from the value
1598 chain. */
1599
3e3d7139 1600void
22bc8444 1601value_decref (struct value *val)
3e3d7139 1602{
466ce3ae 1603 if (val != nullptr)
5f5233d4 1604 {
828d3400
DJ
1605 gdb_assert (val->reference_count > 0);
1606 val->reference_count--;
466ce3ae
TT
1607 if (val->reference_count == 0)
1608 delete val;
5f5233d4 1609 }
3e3d7139
JG
1610}
1611
c906108c
SS
1612/* Free all values allocated since MARK was obtained by value_mark
1613 (except for those released). */
1614void
4bf7b526 1615value_free_to_mark (const struct value *mark)
c906108c 1616{
062d818d
TT
1617 auto iter = std::find (all_values.begin (), all_values.end (), mark);
1618 if (iter == all_values.end ())
1619 all_values.clear ();
1620 else
1621 all_values.erase (iter + 1, all_values.end ());
c906108c
SS
1622}
1623
c906108c
SS
1624/* Remove VAL from the chain all_values
1625 so it will not be freed automatically. */
1626
22bc8444 1627value_ref_ptr
f23631e4 1628release_value (struct value *val)
c906108c 1629{
850645cf
TT
1630 if (val == nullptr)
1631 return value_ref_ptr ();
1632
062d818d
TT
1633 std::vector<value_ref_ptr>::reverse_iterator iter;
1634 for (iter = all_values.rbegin (); iter != all_values.rend (); ++iter)
c906108c 1635 {
062d818d 1636 if (*iter == val)
c906108c 1637 {
062d818d
TT
1638 value_ref_ptr result = *iter;
1639 all_values.erase (iter.base () - 1);
1640 return result;
c906108c
SS
1641 }
1642 }
c906108c 1643
062d818d
TT
1644 /* We must always return an owned reference. Normally this happens
1645 because we transfer the reference from the value chain, but in
1646 this case the value was not on the chain. */
bbfa6f00 1647 return value_ref_ptr::new_reference (val);
e848a8a5
TT
1648}
1649
a6535de1
TT
1650/* See value.h. */
1651
1652std::vector<value_ref_ptr>
4bf7b526 1653value_release_to_mark (const struct value *mark)
c906108c 1654{
a6535de1 1655 std::vector<value_ref_ptr> result;
c906108c 1656
062d818d
TT
1657 auto iter = std::find (all_values.begin (), all_values.end (), mark);
1658 if (iter == all_values.end ())
1659 std::swap (result, all_values);
1660 else
e848a8a5 1661 {
062d818d
TT
1662 std::move (iter + 1, all_values.end (), std::back_inserter (result));
1663 all_values.erase (iter + 1, all_values.end ());
e848a8a5 1664 }
062d818d 1665 std::reverse (result.begin (), result.end ());
a6535de1 1666 return result;
c906108c
SS
1667}
1668
1669/* Return a copy of the value ARG.
1670 It contains the same contents, for same memory address,
1671 but it's a different block of storage. */
1672
f23631e4
AC
1673struct value *
1674value_copy (struct value *arg)
c906108c 1675{
4754a64e 1676 struct type *encl_type = value_enclosing_type (arg);
3e3d7139
JG
1677 struct value *val;
1678
1679 if (value_lazy (arg))
1680 val = allocate_value_lazy (encl_type);
1681 else
1682 val = allocate_value (encl_type);
df407dfe 1683 val->type = arg->type;
c906108c 1684 VALUE_LVAL (val) = VALUE_LVAL (arg);
6f7c8fc2 1685 val->location = arg->location;
df407dfe
AC
1686 val->offset = arg->offset;
1687 val->bitpos = arg->bitpos;
1688 val->bitsize = arg->bitsize;
d69fe07e 1689 val->lazy = arg->lazy;
13c3b5f5 1690 val->embedded_offset = value_embedded_offset (arg);
b44d461b 1691 val->pointed_to_offset = arg->pointed_to_offset;
c906108c 1692 val->modifiable = arg->modifiable;
d69fe07e 1693 if (!value_lazy (val))
c906108c 1694 {
990a07ab 1695 memcpy (value_contents_all_raw (val), value_contents_all_raw (arg),
4754a64e 1696 TYPE_LENGTH (value_enclosing_type (arg)));
c906108c
SS
1697
1698 }
0c7e6dd8
TT
1699 val->unavailable = arg->unavailable;
1700 val->optimized_out = arg->optimized_out;
2c8331b9 1701 val->parent = arg->parent;
5f5233d4
PA
1702 if (VALUE_LVAL (val) == lval_computed)
1703 {
c8f2448a 1704 const struct lval_funcs *funcs = val->location.computed.funcs;
5f5233d4
PA
1705
1706 if (funcs->copy_closure)
dda83cd7 1707 val->location.computed.closure = funcs->copy_closure (val);
5f5233d4 1708 }
c906108c
SS
1709 return val;
1710}
74bcbdf3 1711
4c082a81
SC
1712/* Return a "const" and/or "volatile" qualified version of the value V.
1713 If CNST is true, then the returned value will be qualified with
1714 "const".
1715 if VOLTL is true, then the returned value will be qualified with
1716 "volatile". */
1717
1718struct value *
1719make_cv_value (int cnst, int voltl, struct value *v)
1720{
1721 struct type *val_type = value_type (v);
1722 struct type *enclosing_type = value_enclosing_type (v);
1723 struct value *cv_val = value_copy (v);
1724
1725 deprecated_set_value_type (cv_val,
1726 make_cv_type (cnst, voltl, val_type, NULL));
1727 set_value_enclosing_type (cv_val,
1728 make_cv_type (cnst, voltl, enclosing_type, NULL));
1729
1730 return cv_val;
1731}
1732
c37f7098
KW
1733/* Return a version of ARG that is non-lvalue. */
1734
1735struct value *
1736value_non_lval (struct value *arg)
1737{
1738 if (VALUE_LVAL (arg) != not_lval)
1739 {
1740 struct type *enc_type = value_enclosing_type (arg);
1741 struct value *val = allocate_value (enc_type);
1742
1743 memcpy (value_contents_all_raw (val), value_contents_all (arg),
1744 TYPE_LENGTH (enc_type));
1745 val->type = arg->type;
1746 set_value_embedded_offset (val, value_embedded_offset (arg));
1747 set_value_pointed_to_offset (val, value_pointed_to_offset (arg));
1748 return val;
1749 }
1750 return arg;
1751}
1752
6c659fc2
SC
1753/* Write contents of V at ADDR and set its lval type to be LVAL_MEMORY. */
1754
1755void
1756value_force_lval (struct value *v, CORE_ADDR addr)
1757{
1758 gdb_assert (VALUE_LVAL (v) == not_lval);
1759
1760 write_memory (addr, value_contents_raw (v), TYPE_LENGTH (value_type (v)));
1761 v->lval = lval_memory;
1762 v->location.address = addr;
1763}
1764
74bcbdf3 1765void
0e03807e
TT
1766set_value_component_location (struct value *component,
1767 const struct value *whole)
74bcbdf3 1768{
9920b434
BH
1769 struct type *type;
1770
e81e7f5e
SC
1771 gdb_assert (whole->lval != lval_xcallable);
1772
0e03807e 1773 if (whole->lval == lval_internalvar)
74bcbdf3
PA
1774 VALUE_LVAL (component) = lval_internalvar_component;
1775 else
0e03807e 1776 VALUE_LVAL (component) = whole->lval;
5f5233d4 1777
74bcbdf3 1778 component->location = whole->location;
0e03807e 1779 if (whole->lval == lval_computed)
5f5233d4 1780 {
c8f2448a 1781 const struct lval_funcs *funcs = whole->location.computed.funcs;
5f5233d4
PA
1782
1783 if (funcs->copy_closure)
dda83cd7 1784 component->location.computed.closure = funcs->copy_closure (whole);
5f5233d4 1785 }
9920b434
BH
1786
1787 /* If type has a dynamic resolved location property
1788 update it's value address. */
1789 type = value_type (whole);
1790 if (NULL != TYPE_DATA_LOCATION (type)
1791 && TYPE_DATA_LOCATION_KIND (type) == PROP_CONST)
1792 set_value_address (component, TYPE_DATA_LOCATION_ADDR (type));
74bcbdf3
PA
1793}
1794
c906108c
SS
1795/* Access to the value history. */
1796
1797/* Record a new value in the value history.
eddf0bae 1798 Returns the absolute history index of the entry. */
c906108c
SS
1799
1800int
f23631e4 1801record_latest_value (struct value *val)
c906108c 1802{
c906108c
SS
1803 /* We don't want this value to have anything to do with the inferior anymore.
1804 In particular, "set $1 = 50" should not affect the variable from which
1805 the value was taken, and fast watchpoints should be able to assume that
1806 a value on the value history never changes. */
d69fe07e 1807 if (value_lazy (val))
c906108c
SS
1808 value_fetch_lazy (val);
1809 /* We preserve VALUE_LVAL so that the user can find out where it was fetched
1810 from. This is a bit dubious, because then *&$1 does not just return $1
1811 but the current contents of that location. c'est la vie... */
1812 val->modifiable = 0;
350e1a76 1813
4d0266a0 1814 value_history.push_back (release_value (val));
a109c7c1 1815
4d0266a0 1816 return value_history.size ();
c906108c
SS
1817}
1818
1819/* Return a copy of the value in the history with sequence number NUM. */
1820
f23631e4 1821struct value *
fba45db2 1822access_value_history (int num)
c906108c 1823{
52f0bd74 1824 int absnum = num;
c906108c
SS
1825
1826 if (absnum <= 0)
4d0266a0 1827 absnum += value_history.size ();
c906108c
SS
1828
1829 if (absnum <= 0)
1830 {
1831 if (num == 0)
8a3fe4f8 1832 error (_("The history is empty."));
c906108c 1833 else if (num == 1)
8a3fe4f8 1834 error (_("There is only one value in the history."));
c906108c 1835 else
8a3fe4f8 1836 error (_("History does not go back to $$%d."), -num);
c906108c 1837 }
4d0266a0 1838 if (absnum > value_history.size ())
8a3fe4f8 1839 error (_("History has not yet reached $%d."), absnum);
c906108c
SS
1840
1841 absnum--;
1842
4d0266a0 1843 return value_copy (value_history[absnum].get ());
c906108c
SS
1844}
1845
c906108c 1846static void
5fed81ff 1847show_values (const char *num_exp, int from_tty)
c906108c 1848{
52f0bd74 1849 int i;
f23631e4 1850 struct value *val;
c906108c
SS
1851 static int num = 1;
1852
1853 if (num_exp)
1854 {
f132ba9d 1855 /* "show values +" should print from the stored position.
dda83cd7 1856 "show values <exp>" should print around value number <exp>. */
c906108c 1857 if (num_exp[0] != '+' || num_exp[1] != '\0')
bb518678 1858 num = parse_and_eval_long (num_exp) - 5;
c906108c
SS
1859 }
1860 else
1861 {
f132ba9d 1862 /* "show values" means print the last 10 values. */
4d0266a0 1863 num = value_history.size () - 9;
c906108c
SS
1864 }
1865
1866 if (num <= 0)
1867 num = 1;
1868
4d0266a0 1869 for (i = num; i < num + 10 && i <= value_history.size (); i++)
c906108c 1870 {
79a45b7d 1871 struct value_print_options opts;
a109c7c1 1872
c906108c 1873 val = access_value_history (i);
a3f17187 1874 printf_filtered (("$%d = "), i);
79a45b7d
TT
1875 get_user_print_options (&opts);
1876 value_print (val, gdb_stdout, &opts);
a3f17187 1877 printf_filtered (("\n"));
c906108c
SS
1878 }
1879
f132ba9d 1880 /* The next "show values +" should start after what we just printed. */
c906108c
SS
1881 num += 10;
1882
1883 /* Hitting just return after this command should do the same thing as
f132ba9d
TJB
1884 "show values +". If num_exp is null, this is unnecessary, since
1885 "show values +" is not useful after "show values". */
c906108c 1886 if (from_tty && num_exp)
85c4be7c 1887 set_repeat_arguments ("+");
c906108c
SS
1888}
1889\f
52059ffd
TT
1890enum internalvar_kind
1891{
1892 /* The internal variable is empty. */
1893 INTERNALVAR_VOID,
1894
1895 /* The value of the internal variable is provided directly as
1896 a GDB value object. */
1897 INTERNALVAR_VALUE,
1898
1899 /* A fresh value is computed via a call-back routine on every
1900 access to the internal variable. */
1901 INTERNALVAR_MAKE_VALUE,
1902
1903 /* The internal variable holds a GDB internal convenience function. */
1904 INTERNALVAR_FUNCTION,
1905
1906 /* The variable holds an integer value. */
1907 INTERNALVAR_INTEGER,
1908
1909 /* The variable holds a GDB-provided string. */
1910 INTERNALVAR_STRING,
1911};
1912
1913union internalvar_data
1914{
1915 /* A value object used with INTERNALVAR_VALUE. */
1916 struct value *value;
1917
1918 /* The call-back routine used with INTERNALVAR_MAKE_VALUE. */
1919 struct
1920 {
1921 /* The functions to call. */
1922 const struct internalvar_funcs *functions;
1923
1924 /* The function's user-data. */
1925 void *data;
1926 } make_value;
1927
1928 /* The internal function used with INTERNALVAR_FUNCTION. */
1929 struct
1930 {
1931 struct internal_function *function;
1932 /* True if this is the canonical name for the function. */
1933 int canonical;
1934 } fn;
1935
1936 /* An integer value used with INTERNALVAR_INTEGER. */
1937 struct
1938 {
1939 /* If type is non-NULL, it will be used as the type to generate
1940 a value for this internal variable. If type is NULL, a default
1941 integer type for the architecture is used. */
1942 struct type *type;
1943 LONGEST val;
1944 } integer;
1945
1946 /* A string value used with INTERNALVAR_STRING. */
1947 char *string;
1948};
1949
c906108c
SS
1950/* Internal variables. These are variables within the debugger
1951 that hold values assigned by debugger commands.
1952 The user refers to them with a '$' prefix
1953 that does not appear in the variable names stored internally. */
1954
4fa62494
UW
1955struct internalvar
1956{
1957 struct internalvar *next;
1958 char *name;
4fa62494 1959
78267919
UW
1960 /* We support various different kinds of content of an internal variable.
1961 enum internalvar_kind specifies the kind, and union internalvar_data
1962 provides the data associated with this particular kind. */
1963
52059ffd 1964 enum internalvar_kind kind;
4fa62494 1965
52059ffd 1966 union internalvar_data u;
4fa62494
UW
1967};
1968
c906108c
SS
1969static struct internalvar *internalvars;
1970
3e43a32a
MS
1971/* If the variable does not already exist create it and give it the
1972 value given. If no value is given then the default is zero. */
53e5f3cf 1973static void
0b39b52e 1974init_if_undefined_command (const char* args, int from_tty)
53e5f3cf
AS
1975{
1976 struct internalvar* intvar;
1977
1978 /* Parse the expression - this is taken from set_command(). */
4d01a485 1979 expression_up expr = parse_expression (args);
53e5f3cf
AS
1980
1981 /* Validate the expression.
1982 Was the expression an assignment?
1983 Or even an expression at all? */
1984 if (expr->nelts == 0 || expr->elts[0].opcode != BINOP_ASSIGN)
1985 error (_("Init-if-undefined requires an assignment expression."));
1986
1987 /* Extract the variable from the parsed expression.
1988 In the case of an assign the lvalue will be in elts[1] and elts[2]. */
1989 if (expr->elts[1].opcode != OP_INTERNALVAR)
3e43a32a
MS
1990 error (_("The first parameter to init-if-undefined "
1991 "should be a GDB variable."));
53e5f3cf
AS
1992 intvar = expr->elts[2].internalvar;
1993
1994 /* Only evaluate the expression if the lvalue is void.
85102364 1995 This may still fail if the expression is invalid. */
78267919 1996 if (intvar->kind == INTERNALVAR_VOID)
4d01a485 1997 evaluate_expression (expr.get ());
53e5f3cf
AS
1998}
1999
2000
c906108c
SS
2001/* Look up an internal variable with name NAME. NAME should not
2002 normally include a dollar sign.
2003
2004 If the specified internal variable does not exist,
c4a3d09a 2005 the return value is NULL. */
c906108c
SS
2006
2007struct internalvar *
bc3b79fd 2008lookup_only_internalvar (const char *name)
c906108c 2009{
52f0bd74 2010 struct internalvar *var;
c906108c
SS
2011
2012 for (var = internalvars; var; var = var->next)
5cb316ef 2013 if (strcmp (var->name, name) == 0)
c906108c
SS
2014 return var;
2015
c4a3d09a
MF
2016 return NULL;
2017}
2018
eb3ff9a5
PA
2019/* Complete NAME by comparing it to the names of internal
2020 variables. */
d55637df 2021
eb3ff9a5
PA
2022void
2023complete_internalvar (completion_tracker &tracker, const char *name)
d55637df 2024{
d55637df
TT
2025 struct internalvar *var;
2026 int len;
2027
2028 len = strlen (name);
2029
2030 for (var = internalvars; var; var = var->next)
2031 if (strncmp (var->name, name, len) == 0)
b02f78f9 2032 tracker.add_completion (make_unique_xstrdup (var->name));
d55637df 2033}
c4a3d09a
MF
2034
2035/* Create an internal variable with name NAME and with a void value.
2036 NAME should not normally include a dollar sign. */
2037
2038struct internalvar *
bc3b79fd 2039create_internalvar (const char *name)
c4a3d09a 2040{
8d749320 2041 struct internalvar *var = XNEW (struct internalvar);
a109c7c1 2042
395f9c91 2043 var->name = xstrdup (name);
78267919 2044 var->kind = INTERNALVAR_VOID;
c906108c
SS
2045 var->next = internalvars;
2046 internalvars = var;
2047 return var;
2048}
2049
4aa995e1
PA
2050/* Create an internal variable with name NAME and register FUN as the
2051 function that value_of_internalvar uses to create a value whenever
2052 this variable is referenced. NAME should not normally include a
22d2b532
SDJ
2053 dollar sign. DATA is passed uninterpreted to FUN when it is
2054 called. CLEANUP, if not NULL, is called when the internal variable
2055 is destroyed. It is passed DATA as its only argument. */
4aa995e1
PA
2056
2057struct internalvar *
22d2b532
SDJ
2058create_internalvar_type_lazy (const char *name,
2059 const struct internalvar_funcs *funcs,
2060 void *data)
4aa995e1 2061{
4fa62494 2062 struct internalvar *var = create_internalvar (name);
a109c7c1 2063
78267919 2064 var->kind = INTERNALVAR_MAKE_VALUE;
22d2b532
SDJ
2065 var->u.make_value.functions = funcs;
2066 var->u.make_value.data = data;
4aa995e1
PA
2067 return var;
2068}
c4a3d09a 2069
22d2b532
SDJ
2070/* See documentation in value.h. */
2071
2072int
2073compile_internalvar_to_ax (struct internalvar *var,
2074 struct agent_expr *expr,
2075 struct axs_value *value)
2076{
2077 if (var->kind != INTERNALVAR_MAKE_VALUE
2078 || var->u.make_value.functions->compile_to_ax == NULL)
2079 return 0;
2080
2081 var->u.make_value.functions->compile_to_ax (var, expr, value,
2082 var->u.make_value.data);
2083 return 1;
2084}
2085
c4a3d09a
MF
2086/* Look up an internal variable with name NAME. NAME should not
2087 normally include a dollar sign.
2088
2089 If the specified internal variable does not exist,
2090 one is created, with a void value. */
2091
2092struct internalvar *
bc3b79fd 2093lookup_internalvar (const char *name)
c4a3d09a
MF
2094{
2095 struct internalvar *var;
2096
2097 var = lookup_only_internalvar (name);
2098 if (var)
2099 return var;
2100
2101 return create_internalvar (name);
2102}
2103
78267919
UW
2104/* Return current value of internal variable VAR. For variables that
2105 are not inherently typed, use a value type appropriate for GDBARCH. */
2106
f23631e4 2107struct value *
78267919 2108value_of_internalvar (struct gdbarch *gdbarch, struct internalvar *var)
c906108c 2109{
f23631e4 2110 struct value *val;
0914bcdb
SS
2111 struct trace_state_variable *tsv;
2112
2113 /* If there is a trace state variable of the same name, assume that
2114 is what we really want to see. */
2115 tsv = find_trace_state_variable (var->name);
2116 if (tsv)
2117 {
2118 tsv->value_known = target_get_trace_state_variable_value (tsv->number,
2119 &(tsv->value));
2120 if (tsv->value_known)
2121 val = value_from_longest (builtin_type (gdbarch)->builtin_int64,
2122 tsv->value);
2123 else
2124 val = allocate_value (builtin_type (gdbarch)->builtin_void);
2125 return val;
2126 }
c906108c 2127
78267919 2128 switch (var->kind)
5f5233d4 2129 {
78267919
UW
2130 case INTERNALVAR_VOID:
2131 val = allocate_value (builtin_type (gdbarch)->builtin_void);
2132 break;
4fa62494 2133
78267919
UW
2134 case INTERNALVAR_FUNCTION:
2135 val = allocate_value (builtin_type (gdbarch)->internal_fn);
2136 break;
4fa62494 2137
cab0c772
UW
2138 case INTERNALVAR_INTEGER:
2139 if (!var->u.integer.type)
78267919 2140 val = value_from_longest (builtin_type (gdbarch)->builtin_int,
cab0c772 2141 var->u.integer.val);
78267919 2142 else
cab0c772
UW
2143 val = value_from_longest (var->u.integer.type, var->u.integer.val);
2144 break;
2145
78267919
UW
2146 case INTERNALVAR_STRING:
2147 val = value_cstring (var->u.string, strlen (var->u.string),
2148 builtin_type (gdbarch)->builtin_char);
2149 break;
4fa62494 2150
78267919
UW
2151 case INTERNALVAR_VALUE:
2152 val = value_copy (var->u.value);
4aa995e1
PA
2153 if (value_lazy (val))
2154 value_fetch_lazy (val);
78267919 2155 break;
4aa995e1 2156
78267919 2157 case INTERNALVAR_MAKE_VALUE:
22d2b532
SDJ
2158 val = (*var->u.make_value.functions->make_value) (gdbarch, var,
2159 var->u.make_value.data);
78267919
UW
2160 break;
2161
2162 default:
9b20d036 2163 internal_error (__FILE__, __LINE__, _("bad kind"));
78267919
UW
2164 }
2165
2166 /* Change the VALUE_LVAL to lval_internalvar so that future operations
2167 on this value go back to affect the original internal variable.
2168
2169 Do not do this for INTERNALVAR_MAKE_VALUE variables, as those have
30baf67b 2170 no underlying modifiable state in the internal variable.
78267919
UW
2171
2172 Likewise, if the variable's value is a computed lvalue, we want
2173 references to it to produce another computed lvalue, where
2174 references and assignments actually operate through the
2175 computed value's functions.
2176
2177 This means that internal variables with computed values
2178 behave a little differently from other internal variables:
2179 assignments to them don't just replace the previous value
2180 altogether. At the moment, this seems like the behavior we
2181 want. */
2182
2183 if (var->kind != INTERNALVAR_MAKE_VALUE
2184 && val->lval != lval_computed)
2185 {
2186 VALUE_LVAL (val) = lval_internalvar;
2187 VALUE_INTERNALVAR (val) = var;
5f5233d4 2188 }
d3c139e9 2189
4fa62494
UW
2190 return val;
2191}
d3c139e9 2192
4fa62494
UW
2193int
2194get_internalvar_integer (struct internalvar *var, LONGEST *result)
2195{
3158c6ed 2196 if (var->kind == INTERNALVAR_INTEGER)
4fa62494 2197 {
cab0c772
UW
2198 *result = var->u.integer.val;
2199 return 1;
3158c6ed 2200 }
d3c139e9 2201
3158c6ed
PA
2202 if (var->kind == INTERNALVAR_VALUE)
2203 {
2204 struct type *type = check_typedef (value_type (var->u.value));
2205
78134374 2206 if (type->code () == TYPE_CODE_INT)
3158c6ed
PA
2207 {
2208 *result = value_as_long (var->u.value);
2209 return 1;
2210 }
4fa62494 2211 }
3158c6ed
PA
2212
2213 return 0;
4fa62494 2214}
d3c139e9 2215
4fa62494
UW
2216static int
2217get_internalvar_function (struct internalvar *var,
2218 struct internal_function **result)
2219{
78267919 2220 switch (var->kind)
d3c139e9 2221 {
78267919
UW
2222 case INTERNALVAR_FUNCTION:
2223 *result = var->u.fn.function;
4fa62494 2224 return 1;
d3c139e9 2225
4fa62494
UW
2226 default:
2227 return 0;
2228 }
c906108c
SS
2229}
2230
2231void
6b850546
DT
2232set_internalvar_component (struct internalvar *var,
2233 LONGEST offset, LONGEST bitpos,
2234 LONGEST bitsize, struct value *newval)
c906108c 2235{
4fa62494 2236 gdb_byte *addr;
3ae385af
SM
2237 struct gdbarch *arch;
2238 int unit_size;
c906108c 2239
78267919 2240 switch (var->kind)
4fa62494 2241 {
78267919
UW
2242 case INTERNALVAR_VALUE:
2243 addr = value_contents_writeable (var->u.value);
3ae385af
SM
2244 arch = get_value_arch (var->u.value);
2245 unit_size = gdbarch_addressable_memory_unit_size (arch);
4fa62494
UW
2246
2247 if (bitsize)
50810684 2248 modify_field (value_type (var->u.value), addr + offset,
4fa62494
UW
2249 value_as_long (newval), bitpos, bitsize);
2250 else
3ae385af 2251 memcpy (addr + offset * unit_size, value_contents (newval),
4fa62494
UW
2252 TYPE_LENGTH (value_type (newval)));
2253 break;
78267919
UW
2254
2255 default:
2256 /* We can never get a component of any other kind. */
9b20d036 2257 internal_error (__FILE__, __LINE__, _("set_internalvar_component"));
4fa62494 2258 }
c906108c
SS
2259}
2260
2261void
f23631e4 2262set_internalvar (struct internalvar *var, struct value *val)
c906108c 2263{
78267919 2264 enum internalvar_kind new_kind;
4fa62494 2265 union internalvar_data new_data = { 0 };
c906108c 2266
78267919 2267 if (var->kind == INTERNALVAR_FUNCTION && var->u.fn.canonical)
bc3b79fd
TJB
2268 error (_("Cannot overwrite convenience function %s"), var->name);
2269
4fa62494 2270 /* Prepare new contents. */
78134374 2271 switch (check_typedef (value_type (val))->code ())
4fa62494
UW
2272 {
2273 case TYPE_CODE_VOID:
78267919 2274 new_kind = INTERNALVAR_VOID;
4fa62494
UW
2275 break;
2276
2277 case TYPE_CODE_INTERNAL_FUNCTION:
2278 gdb_assert (VALUE_LVAL (val) == lval_internalvar);
78267919
UW
2279 new_kind = INTERNALVAR_FUNCTION;
2280 get_internalvar_function (VALUE_INTERNALVAR (val),
2281 &new_data.fn.function);
2282 /* Copies created here are never canonical. */
4fa62494
UW
2283 break;
2284
4fa62494 2285 default:
78267919 2286 new_kind = INTERNALVAR_VALUE;
895dafa6
TT
2287 struct value *copy = value_copy (val);
2288 copy->modifiable = 1;
4fa62494
UW
2289
2290 /* Force the value to be fetched from the target now, to avoid problems
2291 later when this internalvar is referenced and the target is gone or
2292 has changed. */
895dafa6
TT
2293 if (value_lazy (copy))
2294 value_fetch_lazy (copy);
4fa62494
UW
2295
2296 /* Release the value from the value chain to prevent it from being
2297 deleted by free_all_values. From here on this function should not
2298 call error () until new_data is installed into the var->u to avoid
2299 leaking memory. */
895dafa6 2300 new_data.value = release_value (copy).release ();
9920b434
BH
2301
2302 /* Internal variables which are created from values with a dynamic
dda83cd7
SM
2303 location don't need the location property of the origin anymore.
2304 The resolved dynamic location is used prior then any other address
2305 when accessing the value.
2306 If we keep it, we would still refer to the origin value.
2307 Remove the location property in case it exist. */
7aa91313 2308 value_type (new_data.value)->remove_dyn_prop (DYN_PROP_DATA_LOCATION);
9920b434 2309
4fa62494
UW
2310 break;
2311 }
2312
2313 /* Clean up old contents. */
2314 clear_internalvar (var);
2315
2316 /* Switch over. */
78267919 2317 var->kind = new_kind;
4fa62494 2318 var->u = new_data;
c906108c
SS
2319 /* End code which must not call error(). */
2320}
2321
4fa62494
UW
2322void
2323set_internalvar_integer (struct internalvar *var, LONGEST l)
2324{
2325 /* Clean up old contents. */
2326 clear_internalvar (var);
2327
cab0c772
UW
2328 var->kind = INTERNALVAR_INTEGER;
2329 var->u.integer.type = NULL;
2330 var->u.integer.val = l;
78267919
UW
2331}
2332
2333void
2334set_internalvar_string (struct internalvar *var, const char *string)
2335{
2336 /* Clean up old contents. */
2337 clear_internalvar (var);
2338
2339 var->kind = INTERNALVAR_STRING;
2340 var->u.string = xstrdup (string);
4fa62494
UW
2341}
2342
2343static void
2344set_internalvar_function (struct internalvar *var, struct internal_function *f)
2345{
2346 /* Clean up old contents. */
2347 clear_internalvar (var);
2348
78267919
UW
2349 var->kind = INTERNALVAR_FUNCTION;
2350 var->u.fn.function = f;
2351 var->u.fn.canonical = 1;
2352 /* Variables installed here are always the canonical version. */
4fa62494
UW
2353}
2354
2355void
2356clear_internalvar (struct internalvar *var)
2357{
2358 /* Clean up old contents. */
78267919 2359 switch (var->kind)
4fa62494 2360 {
78267919 2361 case INTERNALVAR_VALUE:
22bc8444 2362 value_decref (var->u.value);
78267919
UW
2363 break;
2364
2365 case INTERNALVAR_STRING:
2366 xfree (var->u.string);
4fa62494
UW
2367 break;
2368
22d2b532
SDJ
2369 case INTERNALVAR_MAKE_VALUE:
2370 if (var->u.make_value.functions->destroy != NULL)
2371 var->u.make_value.functions->destroy (var->u.make_value.data);
2372 break;
2373
4fa62494 2374 default:
4fa62494
UW
2375 break;
2376 }
2377
78267919
UW
2378 /* Reset to void kind. */
2379 var->kind = INTERNALVAR_VOID;
4fa62494
UW
2380}
2381
baf20f76 2382const char *
4bf7b526 2383internalvar_name (const struct internalvar *var)
c906108c
SS
2384{
2385 return var->name;
2386}
2387
4fa62494
UW
2388static struct internal_function *
2389create_internal_function (const char *name,
2390 internal_function_fn handler, void *cookie)
bc3b79fd 2391{
bc3b79fd 2392 struct internal_function *ifn = XNEW (struct internal_function);
a109c7c1 2393
bc3b79fd
TJB
2394 ifn->name = xstrdup (name);
2395 ifn->handler = handler;
2396 ifn->cookie = cookie;
4fa62494 2397 return ifn;
bc3b79fd
TJB
2398}
2399
2400char *
2401value_internal_function_name (struct value *val)
2402{
4fa62494
UW
2403 struct internal_function *ifn;
2404 int result;
2405
2406 gdb_assert (VALUE_LVAL (val) == lval_internalvar);
2407 result = get_internalvar_function (VALUE_INTERNALVAR (val), &ifn);
2408 gdb_assert (result);
2409
bc3b79fd
TJB
2410 return ifn->name;
2411}
2412
2413struct value *
d452c4bc
UW
2414call_internal_function (struct gdbarch *gdbarch,
2415 const struct language_defn *language,
2416 struct value *func, int argc, struct value **argv)
bc3b79fd 2417{
4fa62494
UW
2418 struct internal_function *ifn;
2419 int result;
2420
2421 gdb_assert (VALUE_LVAL (func) == lval_internalvar);
2422 result = get_internalvar_function (VALUE_INTERNALVAR (func), &ifn);
2423 gdb_assert (result);
2424
d452c4bc 2425 return (*ifn->handler) (gdbarch, language, ifn->cookie, argc, argv);
bc3b79fd
TJB
2426}
2427
2428/* The 'function' command. This does nothing -- it is just a
2429 placeholder to let "help function NAME" work. This is also used as
2430 the implementation of the sub-command that is created when
2431 registering an internal function. */
2432static void
981a3fb3 2433function_command (const char *command, int from_tty)
bc3b79fd
TJB
2434{
2435 /* Do nothing. */
2436}
2437
1a6d41c6
TT
2438/* Helper function that does the work for add_internal_function. */
2439
2440static struct cmd_list_element *
2441do_add_internal_function (const char *name, const char *doc,
2442 internal_function_fn handler, void *cookie)
bc3b79fd 2443{
4fa62494 2444 struct internal_function *ifn;
bc3b79fd 2445 struct internalvar *var = lookup_internalvar (name);
4fa62494
UW
2446
2447 ifn = create_internal_function (name, handler, cookie);
2448 set_internalvar_function (var, ifn);
bc3b79fd 2449
3ea16160 2450 return add_cmd (name, no_class, function_command, doc, &functionlist);
1a6d41c6
TT
2451}
2452
2453/* See value.h. */
2454
2455void
2456add_internal_function (const char *name, const char *doc,
2457 internal_function_fn handler, void *cookie)
2458{
2459 do_add_internal_function (name, doc, handler, cookie);
2460}
2461
2462/* See value.h. */
2463
2464void
3ea16160
TT
2465add_internal_function (gdb::unique_xmalloc_ptr<char> &&name,
2466 gdb::unique_xmalloc_ptr<char> &&doc,
1a6d41c6
TT
2467 internal_function_fn handler, void *cookie)
2468{
2469 struct cmd_list_element *cmd
3ea16160 2470 = do_add_internal_function (name.get (), doc.get (), handler, cookie);
1a6d41c6
TT
2471 doc.release ();
2472 cmd->doc_allocated = 1;
3ea16160
TT
2473 name.release ();
2474 cmd->name_allocated = 1;
bc3b79fd
TJB
2475}
2476
ae5a43e0
DJ
2477/* Update VALUE before discarding OBJFILE. COPIED_TYPES is used to
2478 prevent cycles / duplicates. */
2479
4e7a5ef5 2480void
ae5a43e0
DJ
2481preserve_one_value (struct value *value, struct objfile *objfile,
2482 htab_t copied_types)
2483{
2484 if (TYPE_OBJFILE (value->type) == objfile)
2485 value->type = copy_type_recursive (objfile, value->type, copied_types);
2486
2487 if (TYPE_OBJFILE (value->enclosing_type) == objfile)
2488 value->enclosing_type = copy_type_recursive (objfile,
2489 value->enclosing_type,
2490 copied_types);
2491}
2492
78267919
UW
2493/* Likewise for internal variable VAR. */
2494
2495static void
2496preserve_one_internalvar (struct internalvar *var, struct objfile *objfile,
2497 htab_t copied_types)
2498{
2499 switch (var->kind)
2500 {
cab0c772
UW
2501 case INTERNALVAR_INTEGER:
2502 if (var->u.integer.type && TYPE_OBJFILE (var->u.integer.type) == objfile)
2503 var->u.integer.type
2504 = copy_type_recursive (objfile, var->u.integer.type, copied_types);
2505 break;
2506
78267919
UW
2507 case INTERNALVAR_VALUE:
2508 preserve_one_value (var->u.value, objfile, copied_types);
2509 break;
2510 }
2511}
2512
ae5a43e0
DJ
2513/* Update the internal variables and value history when OBJFILE is
2514 discarded; we must copy the types out of the objfile. New global types
2515 will be created for every convenience variable which currently points to
2516 this objfile's types, and the convenience variables will be adjusted to
2517 use the new global types. */
c906108c
SS
2518
2519void
ae5a43e0 2520preserve_values (struct objfile *objfile)
c906108c 2521{
52f0bd74 2522 struct internalvar *var;
c906108c 2523
ae5a43e0
DJ
2524 /* Create the hash table. We allocate on the objfile's obstack, since
2525 it is soon to be deleted. */
6108fd18 2526 htab_up copied_types = create_copied_types_hash (objfile);
ae5a43e0 2527
4d0266a0 2528 for (const value_ref_ptr &item : value_history)
6108fd18 2529 preserve_one_value (item.get (), objfile, copied_types.get ());
ae5a43e0
DJ
2530
2531 for (var = internalvars; var; var = var->next)
6108fd18 2532 preserve_one_internalvar (var, objfile, copied_types.get ());
ae5a43e0 2533
6108fd18 2534 preserve_ext_lang_values (objfile, copied_types.get ());
c906108c
SS
2535}
2536
2537static void
ad25e423 2538show_convenience (const char *ignore, int from_tty)
c906108c 2539{
e17c207e 2540 struct gdbarch *gdbarch = get_current_arch ();
52f0bd74 2541 struct internalvar *var;
c906108c 2542 int varseen = 0;
79a45b7d 2543 struct value_print_options opts;
c906108c 2544
79a45b7d 2545 get_user_print_options (&opts);
c906108c
SS
2546 for (var = internalvars; var; var = var->next)
2547 {
c709acd1 2548
c906108c
SS
2549 if (!varseen)
2550 {
2551 varseen = 1;
2552 }
a3f17187 2553 printf_filtered (("$%s = "), var->name);
c709acd1 2554
a70b8144 2555 try
c709acd1
PA
2556 {
2557 struct value *val;
2558
2559 val = value_of_internalvar (gdbarch, var);
2560 value_print (val, gdb_stdout, &opts);
2561 }
230d2906 2562 catch (const gdb_exception_error &ex)
492d29ea 2563 {
7f6aba03
TT
2564 fprintf_styled (gdb_stdout, metadata_style.style (),
2565 _("<error: %s>"), ex.what ());
492d29ea 2566 }
492d29ea 2567
a3f17187 2568 printf_filtered (("\n"));
c906108c
SS
2569 }
2570 if (!varseen)
f47f77df
DE
2571 {
2572 /* This text does not mention convenience functions on purpose.
2573 The user can't create them except via Python, and if Python support
2574 is installed this message will never be printed ($_streq will
2575 exist). */
2576 printf_unfiltered (_("No debugger convenience variables now defined.\n"
2577 "Convenience variables have "
2578 "names starting with \"$\";\n"
2579 "use \"set\" as in \"set "
2580 "$foo = 5\" to define them.\n"));
2581 }
c906108c
SS
2582}
2583\f
ba18742c
SM
2584
2585/* See value.h. */
e81e7f5e
SC
2586
2587struct value *
ba18742c 2588value_from_xmethod (xmethod_worker_up &&worker)
e81e7f5e 2589{
ba18742c 2590 struct value *v;
e81e7f5e 2591
ba18742c
SM
2592 v = allocate_value (builtin_type (target_gdbarch ())->xmethod);
2593 v->lval = lval_xcallable;
2594 v->location.xm_worker = worker.release ();
2595 v->modifiable = 0;
e81e7f5e 2596
ba18742c 2597 return v;
e81e7f5e
SC
2598}
2599
2ce1cdbf
DE
2600/* Return the type of the result of TYPE_CODE_XMETHOD value METHOD. */
2601
2602struct type *
6b1747cd 2603result_type_of_xmethod (struct value *method, gdb::array_view<value *> argv)
2ce1cdbf 2604{
78134374 2605 gdb_assert (value_type (method)->code () == TYPE_CODE_XMETHOD
6b1747cd 2606 && method->lval == lval_xcallable && !argv.empty ());
2ce1cdbf 2607
6b1747cd 2608 return method->location.xm_worker->get_result_type (argv[0], argv.slice (1));
2ce1cdbf
DE
2609}
2610
e81e7f5e
SC
2611/* Call the xmethod corresponding to the TYPE_CODE_XMETHOD value METHOD. */
2612
2613struct value *
6b1747cd 2614call_xmethod (struct value *method, gdb::array_view<value *> argv)
e81e7f5e 2615{
78134374 2616 gdb_assert (value_type (method)->code () == TYPE_CODE_XMETHOD
6b1747cd 2617 && method->lval == lval_xcallable && !argv.empty ());
e81e7f5e 2618
6b1747cd 2619 return method->location.xm_worker->invoke (argv[0], argv.slice (1));
e81e7f5e
SC
2620}
2621\f
c906108c
SS
2622/* Extract a value as a C number (either long or double).
2623 Knows how to convert fixed values to double, or
2624 floating values to long.
2625 Does not deallocate the value. */
2626
2627LONGEST
f23631e4 2628value_as_long (struct value *val)
c906108c
SS
2629{
2630 /* This coerces arrays and functions, which is necessary (e.g.
2631 in disassemble_command). It also dereferences references, which
2632 I suspect is the most logical thing to do. */
994b9211 2633 val = coerce_array (val);
0fd88904 2634 return unpack_long (value_type (val), value_contents (val));
c906108c
SS
2635}
2636
581e13c1 2637/* Extract a value as a C pointer. Does not deallocate the value.
4478b372
JB
2638 Note that val's type may not actually be a pointer; value_as_long
2639 handles all the cases. */
c906108c 2640CORE_ADDR
f23631e4 2641value_as_address (struct value *val)
c906108c 2642{
50810684
UW
2643 struct gdbarch *gdbarch = get_type_arch (value_type (val));
2644
c906108c
SS
2645 /* Assume a CORE_ADDR can fit in a LONGEST (for now). Not sure
2646 whether we want this to be true eventually. */
2647#if 0
bf6ae464 2648 /* gdbarch_addr_bits_remove is wrong if we are being called for a
c906108c
SS
2649 non-address (e.g. argument to "signal", "info break", etc.), or
2650 for pointers to char, in which the low bits *are* significant. */
50810684 2651 return gdbarch_addr_bits_remove (gdbarch, value_as_long (val));
c906108c 2652#else
f312f057
JB
2653
2654 /* There are several targets (IA-64, PowerPC, and others) which
2655 don't represent pointers to functions as simply the address of
2656 the function's entry point. For example, on the IA-64, a
2657 function pointer points to a two-word descriptor, generated by
2658 the linker, which contains the function's entry point, and the
2659 value the IA-64 "global pointer" register should have --- to
2660 support position-independent code. The linker generates
2661 descriptors only for those functions whose addresses are taken.
2662
2663 On such targets, it's difficult for GDB to convert an arbitrary
2664 function address into a function pointer; it has to either find
2665 an existing descriptor for that function, or call malloc and
2666 build its own. On some targets, it is impossible for GDB to
2667 build a descriptor at all: the descriptor must contain a jump
2668 instruction; data memory cannot be executed; and code memory
2669 cannot be modified.
2670
2671 Upon entry to this function, if VAL is a value of type `function'
2672 (that is, TYPE_CODE (VALUE_TYPE (val)) == TYPE_CODE_FUNC), then
42ae5230 2673 value_address (val) is the address of the function. This is what
f312f057
JB
2674 you'll get if you evaluate an expression like `main'. The call
2675 to COERCE_ARRAY below actually does all the usual unary
2676 conversions, which includes converting values of type `function'
2677 to `pointer to function'. This is the challenging conversion
2678 discussed above. Then, `unpack_long' will convert that pointer
2679 back into an address.
2680
2681 So, suppose the user types `disassemble foo' on an architecture
2682 with a strange function pointer representation, on which GDB
2683 cannot build its own descriptors, and suppose further that `foo'
2684 has no linker-built descriptor. The address->pointer conversion
2685 will signal an error and prevent the command from running, even
2686 though the next step would have been to convert the pointer
2687 directly back into the same address.
2688
2689 The following shortcut avoids this whole mess. If VAL is a
2690 function, just return its address directly. */
78134374
SM
2691 if (value_type (val)->code () == TYPE_CODE_FUNC
2692 || value_type (val)->code () == TYPE_CODE_METHOD)
42ae5230 2693 return value_address (val);
f312f057 2694
994b9211 2695 val = coerce_array (val);
fc0c74b1
AC
2696
2697 /* Some architectures (e.g. Harvard), map instruction and data
2698 addresses onto a single large unified address space. For
2699 instance: An architecture may consider a large integer in the
2700 range 0x10000000 .. 0x1000ffff to already represent a data
2701 addresses (hence not need a pointer to address conversion) while
2702 a small integer would still need to be converted integer to
2703 pointer to address. Just assume such architectures handle all
2704 integer conversions in a single function. */
2705
2706 /* JimB writes:
2707
2708 I think INTEGER_TO_ADDRESS is a good idea as proposed --- but we
2709 must admonish GDB hackers to make sure its behavior matches the
2710 compiler's, whenever possible.
2711
2712 In general, I think GDB should evaluate expressions the same way
2713 the compiler does. When the user copies an expression out of
2714 their source code and hands it to a `print' command, they should
2715 get the same value the compiler would have computed. Any
2716 deviation from this rule can cause major confusion and annoyance,
2717 and needs to be justified carefully. In other words, GDB doesn't
2718 really have the freedom to do these conversions in clever and
2719 useful ways.
2720
2721 AndrewC pointed out that users aren't complaining about how GDB
2722 casts integers to pointers; they are complaining that they can't
2723 take an address from a disassembly listing and give it to `x/i'.
2724 This is certainly important.
2725
79dd2d24 2726 Adding an architecture method like integer_to_address() certainly
fc0c74b1
AC
2727 makes it possible for GDB to "get it right" in all circumstances
2728 --- the target has complete control over how things get done, so
2729 people can Do The Right Thing for their target without breaking
2730 anyone else. The standard doesn't specify how integers get
2731 converted to pointers; usually, the ABI doesn't either, but
2732 ABI-specific code is a more reasonable place to handle it. */
2733
78134374 2734 if (value_type (val)->code () != TYPE_CODE_PTR
aa006118 2735 && !TYPE_IS_REFERENCE (value_type (val))
50810684
UW
2736 && gdbarch_integer_to_address_p (gdbarch))
2737 return gdbarch_integer_to_address (gdbarch, value_type (val),
0fd88904 2738 value_contents (val));
fc0c74b1 2739
0fd88904 2740 return unpack_long (value_type (val), value_contents (val));
c906108c
SS
2741#endif
2742}
2743\f
2744/* Unpack raw data (copied from debugee, target byte order) at VALADDR
2745 as a long, or as a double, assuming the raw data is described
2746 by type TYPE. Knows how to convert different sizes of values
2747 and can convert between fixed and floating point. We don't assume
2748 any alignment for the raw data. Return value is in host byte order.
2749
2750 If you want functions and arrays to be coerced to pointers, and
2751 references to be dereferenced, call value_as_long() instead.
2752
2753 C++: It is assumed that the front-end has taken care of
2754 all matters concerning pointers to members. A pointer
2755 to member which reaches here is considered to be equivalent
2756 to an INT (or some size). After all, it is only an offset. */
2757
2758LONGEST
fc1a4b47 2759unpack_long (struct type *type, const gdb_byte *valaddr)
c906108c 2760{
34877895 2761 enum bfd_endian byte_order = type_byte_order (type);
78134374 2762 enum type_code code = type->code ();
52f0bd74 2763 int len = TYPE_LENGTH (type);
c6d940a9 2764 int nosign = type->is_unsigned ();
c906108c 2765
c906108c
SS
2766 switch (code)
2767 {
2768 case TYPE_CODE_TYPEDEF:
2769 return unpack_long (check_typedef (type), valaddr);
2770 case TYPE_CODE_ENUM:
4f2aea11 2771 case TYPE_CODE_FLAGS:
c906108c
SS
2772 case TYPE_CODE_BOOL:
2773 case TYPE_CODE_INT:
2774 case TYPE_CODE_CHAR:
2775 case TYPE_CODE_RANGE:
0d5de010 2776 case TYPE_CODE_MEMBERPTR:
4e962e74
TT
2777 {
2778 LONGEST result;
20a5fcbd
TT
2779
2780 if (type->bit_size_differs_p ())
2781 {
2782 unsigned bit_off = type->bit_offset ();
2783 unsigned bit_size = type->bit_size ();
2784 if (bit_size == 0)
2785 {
2786 /* unpack_bits_as_long doesn't handle this case the
2787 way we'd like, so handle it here. */
2788 result = 0;
2789 }
2790 else
2791 result = unpack_bits_as_long (type, valaddr, bit_off, bit_size);
2792 }
4e962e74 2793 else
20a5fcbd
TT
2794 {
2795 if (nosign)
2796 result = extract_unsigned_integer (valaddr, len, byte_order);
2797 else
2798 result = extract_signed_integer (valaddr, len, byte_order);
2799 }
4e962e74 2800 if (code == TYPE_CODE_RANGE)
599088e3 2801 result += type->bounds ()->bias;
4e962e74
TT
2802 return result;
2803 }
c906108c
SS
2804
2805 case TYPE_CODE_FLT:
4ef30785 2806 case TYPE_CODE_DECFLOAT:
50637b26 2807 return target_float_to_longest (valaddr, type);
4ef30785 2808
c906108c
SS
2809 case TYPE_CODE_PTR:
2810 case TYPE_CODE_REF:
aa006118 2811 case TYPE_CODE_RVALUE_REF:
c906108c 2812 /* Assume a CORE_ADDR can fit in a LONGEST (for now). Not sure
dda83cd7 2813 whether we want this to be true eventually. */
4478b372 2814 return extract_typed_address (valaddr, type);
c906108c 2815
c906108c 2816 default:
8a3fe4f8 2817 error (_("Value can't be converted to integer."));
c906108c 2818 }
c906108c
SS
2819}
2820
c906108c
SS
2821/* Unpack raw data (copied from debugee, target byte order) at VALADDR
2822 as a CORE_ADDR, assuming the raw data is described by type TYPE.
2823 We don't assume any alignment for the raw data. Return value is in
2824 host byte order.
2825
2826 If you want functions and arrays to be coerced to pointers, and
1aa20aa8 2827 references to be dereferenced, call value_as_address() instead.
c906108c
SS
2828
2829 C++: It is assumed that the front-end has taken care of
2830 all matters concerning pointers to members. A pointer
2831 to member which reaches here is considered to be equivalent
2832 to an INT (or some size). After all, it is only an offset. */
2833
2834CORE_ADDR
fc1a4b47 2835unpack_pointer (struct type *type, const gdb_byte *valaddr)
c906108c
SS
2836{
2837 /* Assume a CORE_ADDR can fit in a LONGEST (for now). Not sure
2838 whether we want this to be true eventually. */
2839 return unpack_long (type, valaddr);
2840}
4478b372 2841
70100014
UW
2842bool
2843is_floating_value (struct value *val)
2844{
2845 struct type *type = check_typedef (value_type (val));
2846
2847 if (is_floating_type (type))
2848 {
2849 if (!target_float_is_valid (value_contents (val), type))
2850 error (_("Invalid floating value found in program."));
2851 return true;
2852 }
2853
2854 return false;
2855}
2856
c906108c 2857\f
1596cb5d 2858/* Get the value of the FIELDNO'th field (which must be static) of
686d4def 2859 TYPE. */
c906108c 2860
f23631e4 2861struct value *
fba45db2 2862value_static_field (struct type *type, int fieldno)
c906108c 2863{
948e66d9
DJ
2864 struct value *retval;
2865
1596cb5d 2866 switch (TYPE_FIELD_LOC_KIND (type, fieldno))
c906108c 2867 {
1596cb5d 2868 case FIELD_LOC_KIND_PHYSADDR:
940da03e 2869 retval = value_at_lazy (type->field (fieldno).type (),
52e9fde8 2870 TYPE_FIELD_STATIC_PHYSADDR (type, fieldno));
1596cb5d
DE
2871 break;
2872 case FIELD_LOC_KIND_PHYSNAME:
c906108c 2873 {
ff355380 2874 const char *phys_name = TYPE_FIELD_STATIC_PHYSNAME (type, fieldno);
581e13c1 2875 /* TYPE_FIELD_NAME (type, fieldno); */
d12307c1 2876 struct block_symbol sym = lookup_symbol (phys_name, 0, VAR_DOMAIN, 0);
94af9270 2877
d12307c1 2878 if (sym.symbol == NULL)
c906108c 2879 {
a109c7c1 2880 /* With some compilers, e.g. HP aCC, static data members are
581e13c1 2881 reported as non-debuggable symbols. */
3b7344d5
TT
2882 struct bound_minimal_symbol msym
2883 = lookup_minimal_symbol (phys_name, NULL, NULL);
940da03e 2884 struct type *field_type = type->field (fieldno).type ();
a109c7c1 2885
3b7344d5 2886 if (!msym.minsym)
c2e0e465 2887 retval = allocate_optimized_out_value (field_type);
c906108c 2888 else
c2e0e465 2889 retval = value_at_lazy (field_type, BMSYMBOL_VALUE_ADDRESS (msym));
c906108c
SS
2890 }
2891 else
d12307c1 2892 retval = value_of_variable (sym.symbol, sym.block);
1596cb5d 2893 break;
c906108c 2894 }
1596cb5d 2895 default:
f3574227 2896 gdb_assert_not_reached ("unexpected field location kind");
1596cb5d
DE
2897 }
2898
948e66d9 2899 return retval;
c906108c
SS
2900}
2901
4dfea560
DE
2902/* Change the enclosing type of a value object VAL to NEW_ENCL_TYPE.
2903 You have to be careful here, since the size of the data area for the value
2904 is set by the length of the enclosing type. So if NEW_ENCL_TYPE is bigger
2905 than the old enclosing type, you have to allocate more space for the
2906 data. */
2b127877 2907
4dfea560
DE
2908void
2909set_value_enclosing_type (struct value *val, struct type *new_encl_type)
2b127877 2910{
5fdf6324
AB
2911 if (TYPE_LENGTH (new_encl_type) > TYPE_LENGTH (value_enclosing_type (val)))
2912 {
2913 check_type_length_before_alloc (new_encl_type);
2914 val->contents
14c88955
TT
2915 .reset ((gdb_byte *) xrealloc (val->contents.release (),
2916 TYPE_LENGTH (new_encl_type)));
5fdf6324 2917 }
3e3d7139
JG
2918
2919 val->enclosing_type = new_encl_type;
2b127877
DB
2920}
2921
c906108c
SS
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.
581e13c1 2925 FIELDNO says which field. */
c906108c 2926
f23631e4 2927struct value *
6b850546 2928value_primitive_field (struct value *arg1, LONGEST offset,
aa1ee363 2929 int fieldno, struct type *arg_type)
c906108c 2930{
f23631e4 2931 struct value *v;
52f0bd74 2932 struct type *type;
3ae385af
SM
2933 struct gdbarch *arch = get_value_arch (arg1);
2934 int unit_size = gdbarch_addressable_memory_unit_size (arch);
c906108c 2935
f168693b 2936 arg_type = check_typedef (arg_type);
940da03e 2937 type = arg_type->field (fieldno).type ();
c54eabfa
JK
2938
2939 /* Call check_typedef on our type to make sure that, if TYPE
2940 is a TYPE_CODE_TYPEDEF, its length is set to the length
2941 of the target type instead of zero. However, we do not
2942 replace the typedef type by the target type, because we want
2943 to keep the typedef in order to be able to print the type
2944 description correctly. */
2945 check_typedef (type);
c906108c 2946
691a26f5 2947 if (TYPE_FIELD_BITSIZE (arg_type, fieldno))
c906108c 2948 {
22c05d8a
JK
2949 /* Handle packed fields.
2950
2951 Create a new value for the bitfield, with bitpos and bitsize
4ea48cc1
DJ
2952 set. If possible, arrange offset and bitpos so that we can
2953 do a single aligned read of the size of the containing type.
2954 Otherwise, adjust offset to the byte containing the first
2955 bit. Assume that the address, offset, and embedded offset
2956 are sufficiently aligned. */
22c05d8a 2957
6b850546
DT
2958 LONGEST bitpos = TYPE_FIELD_BITPOS (arg_type, fieldno);
2959 LONGEST container_bitsize = TYPE_LENGTH (type) * 8;
4ea48cc1 2960
9a0dc9e3
PA
2961 v = allocate_value_lazy (type);
2962 v->bitsize = TYPE_FIELD_BITSIZE (arg_type, fieldno);
2963 if ((bitpos % container_bitsize) + v->bitsize <= container_bitsize
2964 && TYPE_LENGTH (type) <= (int) sizeof (LONGEST))
2965 v->bitpos = bitpos % container_bitsize;
4ea48cc1 2966 else
9a0dc9e3
PA
2967 v->bitpos = bitpos % 8;
2968 v->offset = (value_embedded_offset (arg1)
2969 + offset
2970 + (bitpos - v->bitpos) / 8);
2971 set_value_parent (v, arg1);
2972 if (!value_lazy (arg1))
2973 value_fetch_lazy (v);
c906108c
SS
2974 }
2975 else if (fieldno < TYPE_N_BASECLASSES (arg_type))
2976 {
2977 /* This field is actually a base subobject, so preserve the
39d37385
PA
2978 entire object's contents for later references to virtual
2979 bases, etc. */
6b850546 2980 LONGEST boffset;
a4e2ee12
DJ
2981
2982 /* Lazy register values with offsets are not supported. */
2983 if (VALUE_LVAL (arg1) == lval_register && value_lazy (arg1))
2984 value_fetch_lazy (arg1);
2985
9a0dc9e3
PA
2986 /* We special case virtual inheritance here because this
2987 requires access to the contents, which we would rather avoid
2988 for references to ordinary fields of unavailable values. */
2989 if (BASETYPE_VIA_VIRTUAL (arg_type, fieldno))
2990 boffset = baseclass_offset (arg_type, fieldno,
2991 value_contents (arg1),
2992 value_embedded_offset (arg1),
2993 value_address (arg1),
2994 arg1);
c906108c 2995 else
9a0dc9e3 2996 boffset = TYPE_FIELD_BITPOS (arg_type, fieldno) / 8;
691a26f5 2997
9a0dc9e3
PA
2998 if (value_lazy (arg1))
2999 v = allocate_value_lazy (value_enclosing_type (arg1));
3000 else
3001 {
3002 v = allocate_value (value_enclosing_type (arg1));
3003 value_contents_copy_raw (v, 0, arg1, 0,
3004 TYPE_LENGTH (value_enclosing_type (arg1)));
3e3d7139 3005 }
9a0dc9e3
PA
3006 v->type = type;
3007 v->offset = value_offset (arg1);
3008 v->embedded_offset = offset + value_embedded_offset (arg1) + boffset;
c906108c 3009 }
9920b434
BH
3010 else if (NULL != TYPE_DATA_LOCATION (type))
3011 {
3012 /* Field is a dynamic data member. */
3013
3014 gdb_assert (0 == offset);
3015 /* We expect an already resolved data location. */
3016 gdb_assert (PROP_CONST == TYPE_DATA_LOCATION_KIND (type));
3017 /* For dynamic data types defer memory allocation
dda83cd7 3018 until we actual access the value. */
9920b434
BH
3019 v = allocate_value_lazy (type);
3020 }
c906108c
SS
3021 else
3022 {
3023 /* Plain old data member */
3ae385af 3024 offset += (TYPE_FIELD_BITPOS (arg_type, fieldno)
dda83cd7 3025 / (HOST_CHAR_BIT * unit_size));
a4e2ee12
DJ
3026
3027 /* Lazy register values with offsets are not supported. */
3028 if (VALUE_LVAL (arg1) == lval_register && value_lazy (arg1))
3029 value_fetch_lazy (arg1);
3030
9a0dc9e3 3031 if (value_lazy (arg1))
3e3d7139 3032 v = allocate_value_lazy (type);
c906108c 3033 else
3e3d7139
JG
3034 {
3035 v = allocate_value (type);
39d37385
PA
3036 value_contents_copy_raw (v, value_embedded_offset (v),
3037 arg1, value_embedded_offset (arg1) + offset,
3ae385af 3038 type_length_units (type));
3e3d7139 3039 }
df407dfe 3040 v->offset = (value_offset (arg1) + offset
13c3b5f5 3041 + value_embedded_offset (arg1));
c906108c 3042 }
74bcbdf3 3043 set_value_component_location (v, arg1);
c906108c
SS
3044 return v;
3045}
3046
3047/* Given a value ARG1 of a struct or union type,
3048 extract and return the value of one of its (non-static) fields.
581e13c1 3049 FIELDNO says which field. */
c906108c 3050
f23631e4 3051struct value *
aa1ee363 3052value_field (struct value *arg1, int fieldno)
c906108c 3053{
df407dfe 3054 return value_primitive_field (arg1, 0, fieldno, value_type (arg1));
c906108c
SS
3055}
3056
3057/* Return a non-virtual function as a value.
3058 F is the list of member functions which contains the desired method.
0478d61c
FF
3059 J is an index into F which provides the desired method.
3060
3061 We only use the symbol for its address, so be happy with either a
581e13c1 3062 full symbol or a minimal symbol. */
c906108c 3063
f23631e4 3064struct value *
3e43a32a
MS
3065value_fn_field (struct value **arg1p, struct fn_field *f,
3066 int j, struct type *type,
6b850546 3067 LONGEST offset)
c906108c 3068{
f23631e4 3069 struct value *v;
52f0bd74 3070 struct type *ftype = TYPE_FN_FIELD_TYPE (f, j);
1d06ead6 3071 const char *physname = TYPE_FN_FIELD_PHYSNAME (f, j);
c906108c 3072 struct symbol *sym;
7c7b6655 3073 struct bound_minimal_symbol msym;
c906108c 3074
d12307c1 3075 sym = lookup_symbol (physname, 0, VAR_DOMAIN, 0).symbol;
5ae326fa 3076 if (sym != NULL)
0478d61c 3077 {
7c7b6655 3078 memset (&msym, 0, sizeof (msym));
5ae326fa
AC
3079 }
3080 else
3081 {
3082 gdb_assert (sym == NULL);
7c7b6655
TT
3083 msym = lookup_bound_minimal_symbol (physname);
3084 if (msym.minsym == NULL)
5ae326fa 3085 return NULL;
0478d61c
FF
3086 }
3087
c906108c 3088 v = allocate_value (ftype);
1a088441 3089 VALUE_LVAL (v) = lval_memory;
0478d61c
FF
3090 if (sym)
3091 {
2b1ffcfd 3092 set_value_address (v, BLOCK_ENTRY_PC (SYMBOL_BLOCK_VALUE (sym)));
0478d61c
FF
3093 }
3094 else
3095 {
bccdca4a
UW
3096 /* The minimal symbol might point to a function descriptor;
3097 resolve it to the actual code address instead. */
7c7b6655 3098 struct objfile *objfile = msym.objfile;
08feed99 3099 struct gdbarch *gdbarch = objfile->arch ();
bccdca4a 3100
42ae5230
TT
3101 set_value_address (v,
3102 gdbarch_convert_from_func_ptr_addr
8b88a78e 3103 (gdbarch, BMSYMBOL_VALUE_ADDRESS (msym), current_top_target ()));
0478d61c 3104 }
c906108c
SS
3105
3106 if (arg1p)
c5aa993b 3107 {
df407dfe 3108 if (type != value_type (*arg1p))
c5aa993b
JM
3109 *arg1p = value_ind (value_cast (lookup_pointer_type (type),
3110 value_addr (*arg1p)));
3111
070ad9f0 3112 /* Move the `this' pointer according to the offset.
dda83cd7 3113 VALUE_OFFSET (*arg1p) += offset; */
c906108c
SS
3114 }
3115
3116 return v;
3117}
3118
c906108c 3119\f
c906108c 3120
ef83a141
TT
3121/* See value.h. */
3122
3123LONGEST
4875ffdb 3124unpack_bits_as_long (struct type *field_type, const gdb_byte *valaddr,
6b850546 3125 LONGEST bitpos, LONGEST bitsize)
c906108c 3126{
34877895 3127 enum bfd_endian byte_order = type_byte_order (field_type);
c906108c
SS
3128 ULONGEST val;
3129 ULONGEST valmask;
c906108c 3130 int lsbcount;
6b850546
DT
3131 LONGEST bytes_read;
3132 LONGEST read_offset;
c906108c 3133
4a76eae5
DJ
3134 /* Read the minimum number of bytes required; there may not be
3135 enough bytes to read an entire ULONGEST. */
f168693b 3136 field_type = check_typedef (field_type);
4a76eae5
DJ
3137 if (bitsize)
3138 bytes_read = ((bitpos % 8) + bitsize + 7) / 8;
3139 else
15ce8941
TT
3140 {
3141 bytes_read = TYPE_LENGTH (field_type);
3142 bitsize = 8 * bytes_read;
3143 }
4a76eae5 3144
5467c6c8
PA
3145 read_offset = bitpos / 8;
3146
4875ffdb 3147 val = extract_unsigned_integer (valaddr + read_offset,
4a76eae5 3148 bytes_read, byte_order);
c906108c 3149
581e13c1 3150 /* Extract bits. See comment above. */
c906108c 3151
d5a22e77 3152 if (byte_order == BFD_ENDIAN_BIG)
4a76eae5 3153 lsbcount = (bytes_read * 8 - bitpos % 8 - bitsize);
c906108c
SS
3154 else
3155 lsbcount = (bitpos % 8);
3156 val >>= lsbcount;
3157
3158 /* If the field does not entirely fill a LONGEST, then zero the sign bits.
581e13c1 3159 If the field is signed, and is negative, then sign extend. */
c906108c 3160
15ce8941 3161 if (bitsize < 8 * (int) sizeof (val))
c906108c
SS
3162 {
3163 valmask = (((ULONGEST) 1) << bitsize) - 1;
3164 val &= valmask;
c6d940a9 3165 if (!field_type->is_unsigned ())
c906108c
SS
3166 {
3167 if (val & (valmask ^ (valmask >> 1)))
3168 {
3169 val |= ~valmask;
3170 }
3171 }
3172 }
5467c6c8 3173
4875ffdb 3174 return val;
5467c6c8
PA
3175}
3176
3177/* Unpack a field FIELDNO of the specified TYPE, from the object at
3178 VALADDR + EMBEDDED_OFFSET. VALADDR points to the contents of
3179 ORIGINAL_VALUE, which must not be NULL. See
3180 unpack_value_bits_as_long for more details. */
3181
3182int
3183unpack_value_field_as_long (struct type *type, const gdb_byte *valaddr,
6b850546 3184 LONGEST embedded_offset, int fieldno,
5467c6c8
PA
3185 const struct value *val, LONGEST *result)
3186{
4875ffdb
PA
3187 int bitpos = TYPE_FIELD_BITPOS (type, fieldno);
3188 int bitsize = TYPE_FIELD_BITSIZE (type, fieldno);
940da03e 3189 struct type *field_type = type->field (fieldno).type ();
4875ffdb
PA
3190 int bit_offset;
3191
5467c6c8
PA
3192 gdb_assert (val != NULL);
3193
4875ffdb
PA
3194 bit_offset = embedded_offset * TARGET_CHAR_BIT + bitpos;
3195 if (value_bits_any_optimized_out (val, bit_offset, bitsize)
3196 || !value_bits_available (val, bit_offset, bitsize))
3197 return 0;
3198
3199 *result = unpack_bits_as_long (field_type, valaddr + embedded_offset,
3200 bitpos, bitsize);
3201 return 1;
5467c6c8
PA
3202}
3203
3204/* Unpack a field FIELDNO of the specified TYPE, from the anonymous
4875ffdb 3205 object at VALADDR. See unpack_bits_as_long for more details. */
5467c6c8
PA
3206
3207LONGEST
3208unpack_field_as_long (struct type *type, const gdb_byte *valaddr, int fieldno)
3209{
4875ffdb
PA
3210 int bitpos = TYPE_FIELD_BITPOS (type, fieldno);
3211 int bitsize = TYPE_FIELD_BITSIZE (type, fieldno);
940da03e 3212 struct type *field_type = type->field (fieldno).type ();
5467c6c8 3213
4875ffdb
PA
3214 return unpack_bits_as_long (field_type, valaddr, bitpos, bitsize);
3215}
3216
3217/* Unpack a bitfield of BITSIZE bits found at BITPOS in the object at
3218 VALADDR + EMBEDDEDOFFSET that has the type of DEST_VAL and store
3219 the contents in DEST_VAL, zero or sign extending if the type of
3220 DEST_VAL is wider than BITSIZE. VALADDR points to the contents of
3221 VAL. If the VAL's contents required to extract the bitfield from
3222 are unavailable/optimized out, DEST_VAL is correspondingly
3223 marked unavailable/optimized out. */
3224
bb9d5f81 3225void
4875ffdb 3226unpack_value_bitfield (struct value *dest_val,
6b850546
DT
3227 LONGEST bitpos, LONGEST bitsize,
3228 const gdb_byte *valaddr, LONGEST embedded_offset,
4875ffdb
PA
3229 const struct value *val)
3230{
3231 enum bfd_endian byte_order;
3232 int src_bit_offset;
3233 int dst_bit_offset;
4875ffdb
PA
3234 struct type *field_type = value_type (dest_val);
3235
34877895 3236 byte_order = type_byte_order (field_type);
e5ca03b4
PA
3237
3238 /* First, unpack and sign extend the bitfield as if it was wholly
3239 valid. Optimized out/unavailable bits are read as zero, but
3240 that's OK, as they'll end up marked below. If the VAL is
3241 wholly-invalid we may have skipped allocating its contents,
3242 though. See allocate_optimized_out_value. */
3243 if (valaddr != NULL)
3244 {
3245 LONGEST num;
3246
3247 num = unpack_bits_as_long (field_type, valaddr + embedded_offset,
3248 bitpos, bitsize);
3249 store_signed_integer (value_contents_raw (dest_val),
3250 TYPE_LENGTH (field_type), byte_order, num);
3251 }
4875ffdb
PA
3252
3253 /* Now copy the optimized out / unavailability ranges to the right
3254 bits. */
3255 src_bit_offset = embedded_offset * TARGET_CHAR_BIT + bitpos;
3256 if (byte_order == BFD_ENDIAN_BIG)
3257 dst_bit_offset = TYPE_LENGTH (field_type) * TARGET_CHAR_BIT - bitsize;
3258 else
3259 dst_bit_offset = 0;
3260 value_ranges_copy_adjusted (dest_val, dst_bit_offset,
3261 val, src_bit_offset, bitsize);
5467c6c8
PA
3262}
3263
3264/* Return a new value with type TYPE, which is FIELDNO field of the
3265 object at VALADDR + EMBEDDEDOFFSET. VALADDR points to the contents
3266 of VAL. If the VAL's contents required to extract the bitfield
4875ffdb
PA
3267 from are unavailable/optimized out, the new value is
3268 correspondingly marked unavailable/optimized out. */
5467c6c8
PA
3269
3270struct value *
3271value_field_bitfield (struct type *type, int fieldno,
3272 const gdb_byte *valaddr,
6b850546 3273 LONGEST embedded_offset, const struct value *val)
5467c6c8 3274{
4875ffdb
PA
3275 int bitpos = TYPE_FIELD_BITPOS (type, fieldno);
3276 int bitsize = TYPE_FIELD_BITSIZE (type, fieldno);
940da03e 3277 struct value *res_val = allocate_value (type->field (fieldno).type ());
5467c6c8 3278
4875ffdb
PA
3279 unpack_value_bitfield (res_val, bitpos, bitsize,
3280 valaddr, embedded_offset, val);
3281
3282 return res_val;
4ea48cc1
DJ
3283}
3284
c906108c
SS
3285/* Modify the value of a bitfield. ADDR points to a block of memory in
3286 target byte order; the bitfield starts in the byte pointed to. FIELDVAL
3287 is the desired value of the field, in host byte order. BITPOS and BITSIZE
581e13c1 3288 indicate which bits (in target bit order) comprise the bitfield.
19f220c3 3289 Requires 0 < BITSIZE <= lbits, 0 <= BITPOS % 8 + BITSIZE <= lbits, and
f4e88c8e 3290 0 <= BITPOS, where lbits is the size of a LONGEST in bits. */
c906108c
SS
3291
3292void
50810684 3293modify_field (struct type *type, gdb_byte *addr,
6b850546 3294 LONGEST fieldval, LONGEST bitpos, LONGEST bitsize)
c906108c 3295{
34877895 3296 enum bfd_endian byte_order = type_byte_order (type);
f4e88c8e
PH
3297 ULONGEST oword;
3298 ULONGEST mask = (ULONGEST) -1 >> (8 * sizeof (ULONGEST) - bitsize);
6b850546 3299 LONGEST bytesize;
19f220c3
JK
3300
3301 /* Normalize BITPOS. */
3302 addr += bitpos / 8;
3303 bitpos %= 8;
c906108c
SS
3304
3305 /* If a negative fieldval fits in the field in question, chop
3306 off the sign extension bits. */
f4e88c8e
PH
3307 if ((~fieldval & ~(mask >> 1)) == 0)
3308 fieldval &= mask;
c906108c
SS
3309
3310 /* Warn if value is too big to fit in the field in question. */
f4e88c8e 3311 if (0 != (fieldval & ~mask))
c906108c
SS
3312 {
3313 /* FIXME: would like to include fieldval in the message, but
dda83cd7 3314 we don't have a sprintf_longest. */
6b850546 3315 warning (_("Value does not fit in %s bits."), plongest (bitsize));
c906108c
SS
3316
3317 /* Truncate it, otherwise adjoining fields may be corrupted. */
f4e88c8e 3318 fieldval &= mask;
c906108c
SS
3319 }
3320
19f220c3
JK
3321 /* Ensure no bytes outside of the modified ones get accessed as it may cause
3322 false valgrind reports. */
3323
3324 bytesize = (bitpos + bitsize + 7) / 8;
3325 oword = extract_unsigned_integer (addr, bytesize, byte_order);
c906108c
SS
3326
3327 /* Shifting for bit field depends on endianness of the target machine. */
d5a22e77 3328 if (byte_order == BFD_ENDIAN_BIG)
19f220c3 3329 bitpos = bytesize * 8 - bitpos - bitsize;
c906108c 3330
f4e88c8e 3331 oword &= ~(mask << bitpos);
c906108c
SS
3332 oword |= fieldval << bitpos;
3333
19f220c3 3334 store_unsigned_integer (addr, bytesize, byte_order, oword);
c906108c
SS
3335}
3336\f
14d06750 3337/* Pack NUM into BUF using a target format of TYPE. */
c906108c 3338
14d06750
DJ
3339void
3340pack_long (gdb_byte *buf, struct type *type, LONGEST num)
c906108c 3341{
34877895 3342 enum bfd_endian byte_order = type_byte_order (type);
6b850546 3343 LONGEST len;
14d06750
DJ
3344
3345 type = check_typedef (type);
c906108c
SS
3346 len = TYPE_LENGTH (type);
3347
78134374 3348 switch (type->code ())
c906108c 3349 {
4e962e74 3350 case TYPE_CODE_RANGE:
599088e3 3351 num -= type->bounds ()->bias;
4e962e74 3352 /* Fall through. */
c906108c
SS
3353 case TYPE_CODE_INT:
3354 case TYPE_CODE_CHAR:
3355 case TYPE_CODE_ENUM:
4f2aea11 3356 case TYPE_CODE_FLAGS:
c906108c 3357 case TYPE_CODE_BOOL:
0d5de010 3358 case TYPE_CODE_MEMBERPTR:
20a5fcbd
TT
3359 if (type->bit_size_differs_p ())
3360 {
3361 unsigned bit_off = type->bit_offset ();
3362 unsigned bit_size = type->bit_size ();
3363 num &= ((ULONGEST) 1 << bit_size) - 1;
3364 num <<= bit_off;
3365 }
e17a4113 3366 store_signed_integer (buf, len, byte_order, num);
c906108c 3367 break;
c5aa993b 3368
c906108c 3369 case TYPE_CODE_REF:
aa006118 3370 case TYPE_CODE_RVALUE_REF:
c906108c 3371 case TYPE_CODE_PTR:
14d06750 3372 store_typed_address (buf, type, (CORE_ADDR) num);
c906108c 3373 break;
c5aa993b 3374
50637b26
UW
3375 case TYPE_CODE_FLT:
3376 case TYPE_CODE_DECFLOAT:
3377 target_float_from_longest (buf, type, num);
3378 break;
3379
c906108c 3380 default:
14d06750 3381 error (_("Unexpected type (%d) encountered for integer constant."),
78134374 3382 type->code ());
c906108c 3383 }
14d06750
DJ
3384}
3385
3386
595939de
PM
3387/* Pack NUM into BUF using a target format of TYPE. */
3388
70221824 3389static void
595939de
PM
3390pack_unsigned_long (gdb_byte *buf, struct type *type, ULONGEST num)
3391{
6b850546 3392 LONGEST len;
595939de
PM
3393 enum bfd_endian byte_order;
3394
3395 type = check_typedef (type);
3396 len = TYPE_LENGTH (type);
34877895 3397 byte_order = type_byte_order (type);
595939de 3398
78134374 3399 switch (type->code ())
595939de
PM
3400 {
3401 case TYPE_CODE_INT:
3402 case TYPE_CODE_CHAR:
3403 case TYPE_CODE_ENUM:
3404 case TYPE_CODE_FLAGS:
3405 case TYPE_CODE_BOOL:
3406 case TYPE_CODE_RANGE:
3407 case TYPE_CODE_MEMBERPTR:
20a5fcbd
TT
3408 if (type->bit_size_differs_p ())
3409 {
3410 unsigned bit_off = type->bit_offset ();
3411 unsigned bit_size = type->bit_size ();
3412 num &= ((ULONGEST) 1 << bit_size) - 1;
3413 num <<= bit_off;
3414 }
595939de
PM
3415 store_unsigned_integer (buf, len, byte_order, num);
3416 break;
3417
3418 case TYPE_CODE_REF:
aa006118 3419 case TYPE_CODE_RVALUE_REF:
595939de
PM
3420 case TYPE_CODE_PTR:
3421 store_typed_address (buf, type, (CORE_ADDR) num);
3422 break;
3423
50637b26
UW
3424 case TYPE_CODE_FLT:
3425 case TYPE_CODE_DECFLOAT:
3426 target_float_from_ulongest (buf, type, num);
3427 break;
3428
595939de 3429 default:
3e43a32a
MS
3430 error (_("Unexpected type (%d) encountered "
3431 "for unsigned integer constant."),
78134374 3432 type->code ());
595939de
PM
3433 }
3434}
3435
3436
14d06750
DJ
3437/* Convert C numbers into newly allocated values. */
3438
3439struct value *
3440value_from_longest (struct type *type, LONGEST num)
3441{
3442 struct value *val = allocate_value (type);
3443
3444 pack_long (value_contents_raw (val), type, num);
c906108c
SS
3445 return val;
3446}
3447
4478b372 3448
595939de
PM
3449/* Convert C unsigned numbers into newly allocated values. */
3450
3451struct value *
3452value_from_ulongest (struct type *type, ULONGEST num)
3453{
3454 struct value *val = allocate_value (type);
3455
3456 pack_unsigned_long (value_contents_raw (val), type, num);
3457
3458 return val;
3459}
3460
3461
4478b372 3462/* Create a value representing a pointer of type TYPE to the address
cb417230 3463 ADDR. */
80180f79 3464
f23631e4 3465struct value *
4478b372
JB
3466value_from_pointer (struct type *type, CORE_ADDR addr)
3467{
cb417230 3468 struct value *val = allocate_value (type);
a109c7c1 3469
80180f79 3470 store_typed_address (value_contents_raw (val),
cb417230 3471 check_typedef (type), addr);
4478b372
JB
3472 return val;
3473}
3474
7584bb30
AB
3475/* Create and return a value object of TYPE containing the value D. The
3476 TYPE must be of TYPE_CODE_FLT, and must be large enough to hold D once
3477 it is converted to target format. */
3478
3479struct value *
3480value_from_host_double (struct type *type, double d)
3481{
3482 struct value *value = allocate_value (type);
78134374 3483 gdb_assert (type->code () == TYPE_CODE_FLT);
7584bb30
AB
3484 target_float_from_host_double (value_contents_raw (value),
3485 value_type (value), d);
3486 return value;
3487}
4478b372 3488
012370f6
TT
3489/* Create a value of type TYPE whose contents come from VALADDR, if it
3490 is non-null, and whose memory address (in the inferior) is
3491 ADDRESS. The type of the created value may differ from the passed
3492 type TYPE. Make sure to retrieve values new type after this call.
3493 Note that TYPE is not passed through resolve_dynamic_type; this is
3494 a special API intended for use only by Ada. */
3495
3496struct value *
3497value_from_contents_and_address_unresolved (struct type *type,
3498 const gdb_byte *valaddr,
3499 CORE_ADDR address)
3500{
3501 struct value *v;
3502
3503 if (valaddr == NULL)
3504 v = allocate_value_lazy (type);
3505 else
3506 v = value_from_contents (type, valaddr);
012370f6 3507 VALUE_LVAL (v) = lval_memory;
1a088441 3508 set_value_address (v, address);
012370f6
TT
3509 return v;
3510}
3511
8acb6b92
TT
3512/* Create a value of type TYPE whose contents come from VALADDR, if it
3513 is non-null, and whose memory address (in the inferior) is
80180f79
SA
3514 ADDRESS. The type of the created value may differ from the passed
3515 type TYPE. Make sure to retrieve values new type after this call. */
8acb6b92
TT
3516
3517struct value *
3518value_from_contents_and_address (struct type *type,
3519 const gdb_byte *valaddr,
3520 CORE_ADDR address)
3521{
b249d2c2
TT
3522 gdb::array_view<const gdb_byte> view;
3523 if (valaddr != nullptr)
3524 view = gdb::make_array_view (valaddr, TYPE_LENGTH (type));
3525 struct type *resolved_type = resolve_dynamic_type (type, view, address);
d36430db 3526 struct type *resolved_type_no_typedef = check_typedef (resolved_type);
41e8491f 3527 struct value *v;
a109c7c1 3528
8acb6b92 3529 if (valaddr == NULL)
80180f79 3530 v = allocate_value_lazy (resolved_type);
8acb6b92 3531 else
80180f79 3532 v = value_from_contents (resolved_type, valaddr);
d36430db
JB
3533 if (TYPE_DATA_LOCATION (resolved_type_no_typedef) != NULL
3534 && TYPE_DATA_LOCATION_KIND (resolved_type_no_typedef) == PROP_CONST)
3535 address = TYPE_DATA_LOCATION_ADDR (resolved_type_no_typedef);
33d502b4 3536 VALUE_LVAL (v) = lval_memory;
1a088441 3537 set_value_address (v, address);
8acb6b92
TT
3538 return v;
3539}
3540
8a9b8146
TT
3541/* Create a value of type TYPE holding the contents CONTENTS.
3542 The new value is `not_lval'. */
3543
3544struct value *
3545value_from_contents (struct type *type, const gdb_byte *contents)
3546{
3547 struct value *result;
3548
3549 result = allocate_value (type);
3550 memcpy (value_contents_raw (result), contents, TYPE_LENGTH (type));
3551 return result;
3552}
3553
3bd0f5ef
MS
3554/* Extract a value from the history file. Input will be of the form
3555 $digits or $$digits. See block comment above 'write_dollar_variable'
3556 for details. */
3557
3558struct value *
e799154c 3559value_from_history_ref (const char *h, const char **endp)
3bd0f5ef
MS
3560{
3561 int index, len;
3562
3563 if (h[0] == '$')
3564 len = 1;
3565 else
3566 return NULL;
3567
3568 if (h[1] == '$')
3569 len = 2;
3570
3571 /* Find length of numeral string. */
3572 for (; isdigit (h[len]); len++)
3573 ;
3574
3575 /* Make sure numeral string is not part of an identifier. */
3576 if (h[len] == '_' || isalpha (h[len]))
3577 return NULL;
3578
3579 /* Now collect the index value. */
3580 if (h[1] == '$')
3581 {
3582 if (len == 2)
3583 {
3584 /* For some bizarre reason, "$$" is equivalent to "$$1",
3585 rather than to "$$0" as it ought to be! */
3586 index = -1;
3587 *endp += len;
3588 }
3589 else
e799154c
TT
3590 {
3591 char *local_end;
3592
3593 index = -strtol (&h[2], &local_end, 10);
3594 *endp = local_end;
3595 }
3bd0f5ef
MS
3596 }
3597 else
3598 {
3599 if (len == 1)
3600 {
3601 /* "$" is equivalent to "$0". */
3602 index = 0;
3603 *endp += len;
3604 }
3605 else
e799154c
TT
3606 {
3607 char *local_end;
3608
3609 index = strtol (&h[1], &local_end, 10);
3610 *endp = local_end;
3611 }
3bd0f5ef
MS
3612 }
3613
3614 return access_value_history (index);
3615}
3616
3fff9862
YQ
3617/* Get the component value (offset by OFFSET bytes) of a struct or
3618 union WHOLE. Component's type is TYPE. */
3619
3620struct value *
3621value_from_component (struct value *whole, struct type *type, LONGEST offset)
3622{
3623 struct value *v;
3624
3625 if (VALUE_LVAL (whole) == lval_memory && value_lazy (whole))
3626 v = allocate_value_lazy (type);
3627 else
3628 {
3629 v = allocate_value (type);
3630 value_contents_copy (v, value_embedded_offset (v),
3631 whole, value_embedded_offset (whole) + offset,
3632 type_length_units (type));
3633 }
3634 v->offset = value_offset (whole) + offset + value_embedded_offset (whole);
3635 set_value_component_location (v, whole);
3fff9862
YQ
3636
3637 return v;
3638}
3639
a471c594
JK
3640struct value *
3641coerce_ref_if_computed (const struct value *arg)
3642{
3643 const struct lval_funcs *funcs;
3644
aa006118 3645 if (!TYPE_IS_REFERENCE (check_typedef (value_type (arg))))
a471c594
JK
3646 return NULL;
3647
3648 if (value_lval_const (arg) != lval_computed)
3649 return NULL;
3650
3651 funcs = value_computed_funcs (arg);
3652 if (funcs->coerce_ref == NULL)
3653 return NULL;
3654
3655 return funcs->coerce_ref (arg);
3656}
3657
dfcee124
AG
3658/* Look at value.h for description. */
3659
3660struct value *
3661readjust_indirect_value_type (struct value *value, struct type *enc_type,
4bf7b526 3662 const struct type *original_type,
e79eb02f
AB
3663 struct value *original_value,
3664 CORE_ADDR original_value_address)
dfcee124 3665{
e79eb02f
AB
3666 gdb_assert (original_type->code () == TYPE_CODE_PTR
3667 || TYPE_IS_REFERENCE (original_type));
3668
3669 struct type *original_target_type = TYPE_TARGET_TYPE (original_type);
3670 gdb::array_view<const gdb_byte> view;
3671 struct type *resolved_original_target_type
3672 = resolve_dynamic_type (original_target_type, view,
3673 original_value_address);
3674
dfcee124 3675 /* Re-adjust type. */
e79eb02f 3676 deprecated_set_value_type (value, resolved_original_target_type);
dfcee124
AG
3677
3678 /* Add embedding info. */
3679 set_value_enclosing_type (value, enc_type);
3680 set_value_embedded_offset (value, value_pointed_to_offset (original_value));
3681
3682 /* We may be pointing to an object of some derived type. */
3683 return value_full_object (value, NULL, 0, 0, 0);
3684}
3685
994b9211
AC
3686struct value *
3687coerce_ref (struct value *arg)
3688{
df407dfe 3689 struct type *value_type_arg_tmp = check_typedef (value_type (arg));
a471c594 3690 struct value *retval;
dfcee124 3691 struct type *enc_type;
a109c7c1 3692
a471c594
JK
3693 retval = coerce_ref_if_computed (arg);
3694 if (retval)
3695 return retval;
3696
aa006118 3697 if (!TYPE_IS_REFERENCE (value_type_arg_tmp))
a471c594
JK
3698 return arg;
3699
dfcee124
AG
3700 enc_type = check_typedef (value_enclosing_type (arg));
3701 enc_type = TYPE_TARGET_TYPE (enc_type);
3702
e79eb02f
AB
3703 CORE_ADDR addr = unpack_pointer (value_type (arg), value_contents (arg));
3704 retval = value_at_lazy (enc_type, addr);
9f1f738a 3705 enc_type = value_type (retval);
e79eb02f
AB
3706 return readjust_indirect_value_type (retval, enc_type, value_type_arg_tmp,
3707 arg, addr);
994b9211
AC
3708}
3709
3710struct value *
3711coerce_array (struct value *arg)
3712{
f3134b88
TT
3713 struct type *type;
3714
994b9211 3715 arg = coerce_ref (arg);
f3134b88
TT
3716 type = check_typedef (value_type (arg));
3717
78134374 3718 switch (type->code ())
f3134b88
TT
3719 {
3720 case TYPE_CODE_ARRAY:
67bd3fd5 3721 if (!type->is_vector () && current_language->c_style_arrays_p ())
f3134b88
TT
3722 arg = value_coerce_array (arg);
3723 break;
3724 case TYPE_CODE_FUNC:
3725 arg = value_coerce_function (arg);
3726 break;
3727 }
994b9211
AC
3728 return arg;
3729}
c906108c 3730\f
c906108c 3731
bbfdfe1c
DM
3732/* Return the return value convention that will be used for the
3733 specified type. */
3734
3735enum return_value_convention
3736struct_return_convention (struct gdbarch *gdbarch,
3737 struct value *function, struct type *value_type)
3738{
78134374 3739 enum type_code code = value_type->code ();
bbfdfe1c
DM
3740
3741 if (code == TYPE_CODE_ERROR)
3742 error (_("Function return type unknown."));
3743
3744 /* Probe the architecture for the return-value convention. */
3745 return gdbarch_return_value (gdbarch, function, value_type,
3746 NULL, NULL, NULL);
3747}
3748
48436ce6
AC
3749/* Return true if the function returning the specified type is using
3750 the convention of returning structures in memory (passing in the
82585c72 3751 address as a hidden first parameter). */
c906108c
SS
3752
3753int
d80b854b 3754using_struct_return (struct gdbarch *gdbarch,
6a3a010b 3755 struct value *function, struct type *value_type)
c906108c 3756{
78134374 3757 if (value_type->code () == TYPE_CODE_VOID)
667e784f 3758 /* A void return value is never in memory. See also corresponding
44e5158b 3759 code in "print_return_value". */
667e784f
AC
3760 return 0;
3761
bbfdfe1c 3762 return (struct_return_convention (gdbarch, function, value_type)
31db7b6c 3763 != RETURN_VALUE_REGISTER_CONVENTION);
c906108c
SS
3764}
3765
42be36b3
CT
3766/* Set the initialized field in a value struct. */
3767
3768void
3769set_value_initialized (struct value *val, int status)
3770{
3771 val->initialized = status;
3772}
3773
3774/* Return the initialized field in a value struct. */
3775
3776int
4bf7b526 3777value_initialized (const struct value *val)
42be36b3
CT
3778{
3779 return val->initialized;
3780}
3781
41c60b4b
SM
3782/* Helper for value_fetch_lazy when the value is a bitfield. */
3783
3784static void
3785value_fetch_lazy_bitfield (struct value *val)
3786{
3787 gdb_assert (value_bitsize (val) != 0);
3788
3789 /* To read a lazy bitfield, read the entire enclosing value. This
3790 prevents reading the same block of (possibly volatile) memory once
3791 per bitfield. It would be even better to read only the containing
3792 word, but we have no way to record that just specific bits of a
3793 value have been fetched. */
41c60b4b
SM
3794 struct value *parent = value_parent (val);
3795
3796 if (value_lazy (parent))
3797 value_fetch_lazy (parent);
3798
3799 unpack_value_bitfield (val, value_bitpos (val), value_bitsize (val),
3800 value_contents_for_printing (parent),
3801 value_offset (val), parent);
3802}
3803
3804/* Helper for value_fetch_lazy when the value is in memory. */
3805
3806static void
3807value_fetch_lazy_memory (struct value *val)
3808{
3809 gdb_assert (VALUE_LVAL (val) == lval_memory);
3810
3811 CORE_ADDR addr = value_address (val);
3812 struct type *type = check_typedef (value_enclosing_type (val));
3813
3814 if (TYPE_LENGTH (type))
3815 read_value_memory (val, 0, value_stack (val),
3816 addr, value_contents_all_raw (val),
3817 type_length_units (type));
3818}
3819
3820/* Helper for value_fetch_lazy when the value is in a register. */
3821
3822static void
3823value_fetch_lazy_register (struct value *val)
3824{
3825 struct frame_info *next_frame;
3826 int regnum;
3827 struct type *type = check_typedef (value_type (val));
3828 struct value *new_val = val, *mark = value_mark ();
3829
3830 /* Offsets are not supported here; lazy register values must
3831 refer to the entire register. */
3832 gdb_assert (value_offset (val) == 0);
3833
3834 while (VALUE_LVAL (new_val) == lval_register && value_lazy (new_val))
3835 {
3836 struct frame_id next_frame_id = VALUE_NEXT_FRAME_ID (new_val);
3837
3838 next_frame = frame_find_by_id (next_frame_id);
3839 regnum = VALUE_REGNUM (new_val);
3840
3841 gdb_assert (next_frame != NULL);
3842
3843 /* Convertible register routines are used for multi-register
3844 values and for interpretation in different types
3845 (e.g. float or int from a double register). Lazy
3846 register values should have the register's natural type,
3847 so they do not apply. */
3848 gdb_assert (!gdbarch_convert_register_p (get_frame_arch (next_frame),
3849 regnum, type));
3850
3851 /* FRAME was obtained, above, via VALUE_NEXT_FRAME_ID.
3852 Since a "->next" operation was performed when setting
3853 this field, we do not need to perform a "next" operation
3854 again when unwinding the register. That's why
3855 frame_unwind_register_value() is called here instead of
3856 get_frame_register_value(). */
3857 new_val = frame_unwind_register_value (next_frame, regnum);
3858
3859 /* If we get another lazy lval_register value, it means the
3860 register is found by reading it from NEXT_FRAME's next frame.
3861 frame_unwind_register_value should never return a value with
3862 the frame id pointing to NEXT_FRAME. If it does, it means we
3863 either have two consecutive frames with the same frame id
3864 in the frame chain, or some code is trying to unwind
3865 behind get_prev_frame's back (e.g., a frame unwind
3866 sniffer trying to unwind), bypassing its validations. In
3867 any case, it should always be an internal error to end up
3868 in this situation. */
3869 if (VALUE_LVAL (new_val) == lval_register
3870 && value_lazy (new_val)
3871 && frame_id_eq (VALUE_NEXT_FRAME_ID (new_val), next_frame_id))
3872 internal_error (__FILE__, __LINE__,
3873 _("infinite loop while fetching a register"));
3874 }
3875
3876 /* If it's still lazy (for instance, a saved register on the
3877 stack), fetch it. */
3878 if (value_lazy (new_val))
3879 value_fetch_lazy (new_val);
3880
3881 /* Copy the contents and the unavailability/optimized-out
3882 meta-data from NEW_VAL to VAL. */
3883 set_value_lazy (val, 0);
3884 value_contents_copy (val, value_embedded_offset (val),
3885 new_val, value_embedded_offset (new_val),
3886 type_length_units (type));
3887
3888 if (frame_debug)
3889 {
3890 struct gdbarch *gdbarch;
3891 struct frame_info *frame;
3892 /* VALUE_FRAME_ID is used here, instead of VALUE_NEXT_FRAME_ID,
3893 so that the frame level will be shown correctly. */
3894 frame = frame_find_by_id (VALUE_FRAME_ID (val));
3895 regnum = VALUE_REGNUM (val);
3896 gdbarch = get_frame_arch (frame);
3897
3898 fprintf_unfiltered (gdb_stdlog,
3899 "{ value_fetch_lazy "
3900 "(frame=%d,regnum=%d(%s),...) ",
3901 frame_relative_level (frame), regnum,
3902 user_reg_map_regnum_to_name (gdbarch, regnum));
3903
3904 fprintf_unfiltered (gdb_stdlog, "->");
3905 if (value_optimized_out (new_val))
3906 {
3907 fprintf_unfiltered (gdb_stdlog, " ");
3908 val_print_optimized_out (new_val, gdb_stdlog);
3909 }
3910 else
3911 {
3912 int i;
3913 const gdb_byte *buf = value_contents (new_val);
3914
3915 if (VALUE_LVAL (new_val) == lval_register)
3916 fprintf_unfiltered (gdb_stdlog, " register=%d",
3917 VALUE_REGNUM (new_val));
3918 else if (VALUE_LVAL (new_val) == lval_memory)
3919 fprintf_unfiltered (gdb_stdlog, " address=%s",
3920 paddress (gdbarch,
3921 value_address (new_val)));
3922 else
3923 fprintf_unfiltered (gdb_stdlog, " computed");
3924
3925 fprintf_unfiltered (gdb_stdlog, " bytes=");
3926 fprintf_unfiltered (gdb_stdlog, "[");
3927 for (i = 0; i < register_size (gdbarch, regnum); i++)
3928 fprintf_unfiltered (gdb_stdlog, "%02x", buf[i]);
3929 fprintf_unfiltered (gdb_stdlog, "]");
3930 }
3931
3932 fprintf_unfiltered (gdb_stdlog, " }\n");
3933 }
3934
3935 /* Dispose of the intermediate values. This prevents
3936 watchpoints from trying to watch the saved frame pointer. */
3937 value_free_to_mark (mark);
3938}
3939
a844296a
SM
3940/* Load the actual content of a lazy value. Fetch the data from the
3941 user's process and clear the lazy flag to indicate that the data in
3942 the buffer is valid.
a58e2656
AB
3943
3944 If the value is zero-length, we avoid calling read_memory, which
3945 would abort. We mark the value as fetched anyway -- all 0 bytes of
a844296a 3946 it. */
a58e2656 3947
a844296a 3948void
a58e2656
AB
3949value_fetch_lazy (struct value *val)
3950{
3951 gdb_assert (value_lazy (val));
3952 allocate_value_contents (val);
9a0dc9e3
PA
3953 /* A value is either lazy, or fully fetched. The
3954 availability/validity is only established as we try to fetch a
3955 value. */
0c7e6dd8
TT
3956 gdb_assert (val->optimized_out.empty ());
3957 gdb_assert (val->unavailable.empty ());
a58e2656 3958 if (value_bitsize (val))
41c60b4b 3959 value_fetch_lazy_bitfield (val);
a58e2656 3960 else if (VALUE_LVAL (val) == lval_memory)
41c60b4b 3961 value_fetch_lazy_memory (val);
a58e2656 3962 else if (VALUE_LVAL (val) == lval_register)
41c60b4b 3963 value_fetch_lazy_register (val);
a58e2656
AB
3964 else if (VALUE_LVAL (val) == lval_computed
3965 && value_computed_funcs (val)->read != NULL)
3966 value_computed_funcs (val)->read (val);
a58e2656
AB
3967 else
3968 internal_error (__FILE__, __LINE__, _("Unexpected lazy value type."));
3969
3970 set_value_lazy (val, 0);
a58e2656
AB
3971}
3972
a280dbd1
SDJ
3973/* Implementation of the convenience function $_isvoid. */
3974
3975static struct value *
3976isvoid_internal_fn (struct gdbarch *gdbarch,
3977 const struct language_defn *language,
3978 void *cookie, int argc, struct value **argv)
3979{
3980 int ret;
3981
3982 if (argc != 1)
6bc305f5 3983 error (_("You must provide one argument for $_isvoid."));
a280dbd1 3984
78134374 3985 ret = value_type (argv[0])->code () == TYPE_CODE_VOID;
a280dbd1
SDJ
3986
3987 return value_from_longest (builtin_type (gdbarch)->builtin_int, ret);
3988}
3989
53a008a6 3990/* Implementation of the convenience function $_creal. Extracts the
8bdc1658
AB
3991 real part from a complex number. */
3992
3993static struct value *
3994creal_internal_fn (struct gdbarch *gdbarch,
3995 const struct language_defn *language,
3996 void *cookie, int argc, struct value **argv)
3997{
3998 if (argc != 1)
3999 error (_("You must provide one argument for $_creal."));
4000
4001 value *cval = argv[0];
4002 type *ctype = check_typedef (value_type (cval));
78134374 4003 if (ctype->code () != TYPE_CODE_COMPLEX)
8bdc1658 4004 error (_("expected a complex number"));
4c99290d 4005 return value_real_part (cval);
8bdc1658
AB
4006}
4007
4008/* Implementation of the convenience function $_cimag. Extracts the
4009 imaginary part from a complex number. */
4010
4011static struct value *
4012cimag_internal_fn (struct gdbarch *gdbarch,
4013 const struct language_defn *language,
4014 void *cookie, int argc,
4015 struct value **argv)
4016{
4017 if (argc != 1)
4018 error (_("You must provide one argument for $_cimag."));
4019
4020 value *cval = argv[0];
4021 type *ctype = check_typedef (value_type (cval));
78134374 4022 if (ctype->code () != TYPE_CODE_COMPLEX)
8bdc1658 4023 error (_("expected a complex number"));
4c99290d 4024 return value_imaginary_part (cval);
8bdc1658
AB
4025}
4026
d5f4488f
SM
4027#if GDB_SELF_TEST
4028namespace selftests
4029{
4030
4031/* Test the ranges_contain function. */
4032
4033static void
4034test_ranges_contain ()
4035{
4036 std::vector<range> ranges;
4037 range r;
4038
4039 /* [10, 14] */
4040 r.offset = 10;
4041 r.length = 5;
4042 ranges.push_back (r);
4043
4044 /* [20, 24] */
4045 r.offset = 20;
4046 r.length = 5;
4047 ranges.push_back (r);
4048
4049 /* [2, 6] */
4050 SELF_CHECK (!ranges_contain (ranges, 2, 5));
4051 /* [9, 13] */
4052 SELF_CHECK (ranges_contain (ranges, 9, 5));
4053 /* [10, 11] */
4054 SELF_CHECK (ranges_contain (ranges, 10, 2));
4055 /* [10, 14] */
4056 SELF_CHECK (ranges_contain (ranges, 10, 5));
4057 /* [13, 18] */
4058 SELF_CHECK (ranges_contain (ranges, 13, 6));
4059 /* [14, 18] */
4060 SELF_CHECK (ranges_contain (ranges, 14, 5));
4061 /* [15, 18] */
4062 SELF_CHECK (!ranges_contain (ranges, 15, 4));
4063 /* [16, 19] */
4064 SELF_CHECK (!ranges_contain (ranges, 16, 4));
4065 /* [16, 21] */
4066 SELF_CHECK (ranges_contain (ranges, 16, 6));
4067 /* [21, 21] */
4068 SELF_CHECK (ranges_contain (ranges, 21, 1));
4069 /* [21, 25] */
4070 SELF_CHECK (ranges_contain (ranges, 21, 5));
4071 /* [26, 28] */
4072 SELF_CHECK (!ranges_contain (ranges, 26, 3));
4073}
4074
4075/* Check that RANGES contains the same ranges as EXPECTED. */
4076
4077static bool
4078check_ranges_vector (gdb::array_view<const range> ranges,
4079 gdb::array_view<const range> expected)
4080{
4081 return ranges == expected;
4082}
4083
4084/* Test the insert_into_bit_range_vector function. */
4085
4086static void
4087test_insert_into_bit_range_vector ()
4088{
4089 std::vector<range> ranges;
4090
4091 /* [10, 14] */
4092 {
4093 insert_into_bit_range_vector (&ranges, 10, 5);
4094 static const range expected[] = {
4095 {10, 5}
4096 };
4097 SELF_CHECK (check_ranges_vector (ranges, expected));
4098 }
4099
4100 /* [10, 14] */
4101 {
4102 insert_into_bit_range_vector (&ranges, 11, 4);
4103 static const range expected = {10, 5};
4104 SELF_CHECK (check_ranges_vector (ranges, expected));
4105 }
4106
4107 /* [10, 14] [20, 24] */
4108 {
4109 insert_into_bit_range_vector (&ranges, 20, 5);
4110 static const range expected[] = {
4111 {10, 5},
4112 {20, 5},
4113 };
4114 SELF_CHECK (check_ranges_vector (ranges, expected));
4115 }
4116
4117 /* [10, 14] [17, 24] */
4118 {
4119 insert_into_bit_range_vector (&ranges, 17, 5);
4120 static const range expected[] = {
4121 {10, 5},
4122 {17, 8},
4123 };
4124 SELF_CHECK (check_ranges_vector (ranges, expected));
4125 }
4126
4127 /* [2, 8] [10, 14] [17, 24] */
4128 {
4129 insert_into_bit_range_vector (&ranges, 2, 7);
4130 static const range expected[] = {
4131 {2, 7},
4132 {10, 5},
4133 {17, 8},
4134 };
4135 SELF_CHECK (check_ranges_vector (ranges, expected));
4136 }
4137
4138 /* [2, 14] [17, 24] */
4139 {
4140 insert_into_bit_range_vector (&ranges, 9, 1);
4141 static const range expected[] = {
4142 {2, 13},
4143 {17, 8},
4144 };
4145 SELF_CHECK (check_ranges_vector (ranges, expected));
4146 }
4147
4148 /* [2, 14] [17, 24] */
4149 {
4150 insert_into_bit_range_vector (&ranges, 9, 1);
4151 static const range expected[] = {
4152 {2, 13},
4153 {17, 8},
4154 };
4155 SELF_CHECK (check_ranges_vector (ranges, expected));
4156 }
4157
4158 /* [2, 33] */
4159 {
4160 insert_into_bit_range_vector (&ranges, 4, 30);
4161 static const range expected = {2, 32};
4162 SELF_CHECK (check_ranges_vector (ranges, expected));
4163 }
4164}
4165
4166} /* namespace selftests */
4167#endif /* GDB_SELF_TEST */
4168
6c265988 4169void _initialize_values ();
c906108c 4170void
6c265988 4171_initialize_values ()
c906108c 4172{
1a966eab 4173 add_cmd ("convenience", no_class, show_convenience, _("\
f47f77df
DE
4174Debugger convenience (\"$foo\") variables and functions.\n\
4175Convenience variables are created when you assign them values;\n\
4176thus, \"set $foo=1\" gives \"$foo\" the value 1. Values may be any type.\n\
1a966eab 4177\n\
c906108c
SS
4178A few convenience variables are given values automatically:\n\
4179\"$_\"holds the last address examined with \"x\" or \"info lines\",\n\
f47f77df
DE
4180\"$__\" holds the contents of the last address examined with \"x\"."
4181#ifdef HAVE_PYTHON
4182"\n\n\
4183Convenience functions are defined via the Python API."
4184#endif
4185 ), &showlist);
7e20dfcd 4186 add_alias_cmd ("conv", "convenience", no_class, 1, &showlist);
c906108c 4187
db5f229b 4188 add_cmd ("values", no_set_class, show_values, _("\
3e43a32a 4189Elements of value history around item number IDX (or last ten)."),
c906108c 4190 &showlist);
53e5f3cf
AS
4191
4192 add_com ("init-if-undefined", class_vars, init_if_undefined_command, _("\
4193Initialize a convenience variable if necessary.\n\
4194init-if-undefined VARIABLE = EXPRESSION\n\
4195Set an internal VARIABLE to the result of the EXPRESSION if it does not\n\
4196exist or does not contain a value. The EXPRESSION is not evaluated if the\n\
4197VARIABLE is already initialized."));
bc3b79fd
TJB
4198
4199 add_prefix_cmd ("function", no_class, function_command, _("\
4200Placeholder command for showing help on convenience functions."),
4201 &functionlist, "function ", 0, &cmdlist);
a280dbd1
SDJ
4202
4203 add_internal_function ("_isvoid", _("\
4204Check whether an expression is void.\n\
4205Usage: $_isvoid (expression)\n\
4206Return 1 if the expression is void, zero otherwise."),
4207 isvoid_internal_fn, NULL);
5fdf6324 4208
8bdc1658
AB
4209 add_internal_function ("_creal", _("\
4210Extract the real part of a complex number.\n\
4211Usage: $_creal (expression)\n\
4212Return the real part of a complex number, the type depends on the\n\
4213type of a complex number."),
4214 creal_internal_fn, NULL);
4215
4216 add_internal_function ("_cimag", _("\
4217Extract the imaginary part of a complex number.\n\
4218Usage: $_cimag (expression)\n\
4219Return the imaginary part of a complex number, the type depends on the\n\
4220type of a complex number."),
4221 cimag_internal_fn, NULL);
4222
5fdf6324
AB
4223 add_setshow_zuinteger_unlimited_cmd ("max-value-size",
4224 class_support, &max_value_size, _("\
4225Set maximum sized value gdb will load from the inferior."), _("\
4226Show maximum sized value gdb will load from the inferior."), _("\
4227Use this to control the maximum size, in bytes, of a value that gdb\n\
4228will load from the inferior. Setting this value to 'unlimited'\n\
4229disables checking.\n\
4230Setting this does not invalidate already allocated values, it only\n\
4231prevents future values, larger than this size, from being allocated."),
4232 set_max_value_size,
4233 show_max_value_size,
4234 &setlist, &showlist);
d5f4488f
SM
4235#if GDB_SELF_TEST
4236 selftests::register_test ("ranges_contain", selftests::test_ranges_contain);
4237 selftests::register_test ("insert_into_bit_range_vector",
4238 selftests::test_insert_into_bit_range_vector);
4239#endif
c906108c 4240}
9d1447e0
SDJ
4241
4242/* See value.h. */
4243
4244void
4245finalize_values ()
4246{
4247 all_values.clear ();
4248}