aboutsummaryrefslogtreecommitdiff
path: root/gdb/regcache.c
blob: 5eb16cc74f8d7d17da6cd2bca5753adbb0a22794 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
/* Cache and manage the values of registers for GDB, the GNU debugger.

   Copyright (C) 1986, 1987, 1989, 1991, 1994, 1995, 1996, 1998, 2000, 2001,
   2002, 2004, 2007 Free Software Foundation, Inc.

   This file is part of GDB.

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 3 of the License, or
   (at your option) any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */

#include "defs.h"
#include "inferior.h"
#include "target.h"
#include "gdbarch.h"
#include "gdbcmd.h"
#include "regcache.h"
#include "reggroups.h"
#include "gdb_assert.h"
#include "gdb_string.h"
#include "gdbcmd.h"		/* For maintenanceprintlist.  */
#include "observer.h"

/*
 * DATA STRUCTURE
 *
 * Here is the actual register cache.
 */

/* Per-architecture object describing the layout of a register cache.
   Computed once when the architecture is created */

struct gdbarch_data *regcache_descr_handle;

struct regcache_descr
{
  /* The architecture this descriptor belongs to.  */
  struct gdbarch *gdbarch;

  /* The raw register cache.  Each raw (or hard) register is supplied
     by the target interface.  The raw cache should not contain
     redundant information - if the PC is constructed from two
     registers then those registers and not the PC lives in the raw
     cache.  */
  int nr_raw_registers;
  long sizeof_raw_registers;
  long sizeof_raw_register_valid_p;

  /* The cooked register space.  Each cooked register in the range
     [0..NR_RAW_REGISTERS) is direct-mapped onto the corresponding raw
     register.  The remaining [NR_RAW_REGISTERS
     .. NR_COOKED_REGISTERS) (a.k.a. pseudo registers) are mapped onto
     both raw registers and memory by the architecture methods
     gdbarch_pseudo_register_read and gdbarch_pseudo_register_write.  */
  int nr_cooked_registers;
  long sizeof_cooked_registers;
  long sizeof_cooked_register_valid_p;

  /* Offset and size (in 8 bit bytes), of reach register in the
     register cache.  All registers (including those in the range
     [NR_RAW_REGISTERS .. NR_COOKED_REGISTERS) are given an offset.
     Assigning all registers an offset makes it possible to keep
     legacy code, such as that found in read_register_bytes() and
     write_register_bytes() working.  */
  long *register_offset;
  long *sizeof_register;

  /* Cached table containing the type of each register.  */
  struct type **register_type;
};

static void *
init_regcache_descr (struct gdbarch *gdbarch)
{
  int i;
  struct regcache_descr *descr;
  gdb_assert (gdbarch != NULL);

  /* Create an initial, zero filled, table.  */
  descr = GDBARCH_OBSTACK_ZALLOC (gdbarch, struct regcache_descr);
  descr->gdbarch = gdbarch;

  /* Total size of the register space.  The raw registers are mapped
     directly onto the raw register cache while the pseudo's are
     either mapped onto raw-registers or memory.  */
  descr->nr_cooked_registers = gdbarch_num_regs (current_gdbarch)
			       + gdbarch_num_pseudo_regs (current_gdbarch);
  descr->sizeof_cooked_register_valid_p = gdbarch_num_regs (current_gdbarch)
					  + gdbarch_num_pseudo_regs 
					      (current_gdbarch);

  /* Fill in a table of register types.  */
  descr->register_type
    = GDBARCH_OBSTACK_CALLOC (gdbarch, descr->nr_cooked_registers, struct type *);
  for (i = 0; i < descr->nr_cooked_registers; i++)
    descr->register_type[i] = gdbarch_register_type (gdbarch, i);

  /* Construct a strictly RAW register cache.  Don't allow pseudo's
     into the register cache.  */
  descr->nr_raw_registers = gdbarch_num_regs (current_gdbarch);

  /* FIXME: cagney/2002-08-13: Overallocate the register_valid_p
     array.  This pretects GDB from erant code that accesses elements
     of the global register_valid_p[] array in the range 
     [gdbarch_num_regs .. gdbarch_num_regs + gdbarch_num_pseudo_regs).  */
  descr->sizeof_raw_register_valid_p = descr->sizeof_cooked_register_valid_p;

  /* Lay out the register cache.

     NOTE: cagney/2002-05-22: Only register_type() is used when
     constructing the register cache.  It is assumed that the
     register's raw size, virtual size and type length are all the
     same.  */

  {
    long offset = 0;
    descr->sizeof_register
      = GDBARCH_OBSTACK_CALLOC (gdbarch, descr->nr_cooked_registers, long);
    descr->register_offset
      = GDBARCH_OBSTACK_CALLOC (gdbarch, descr->nr_cooked_registers, long);
    for (i = 0; i < descr->nr_cooked_registers; i++)
      {
	descr->sizeof_register[i] = TYPE_LENGTH (descr->register_type[i]);
	descr->register_offset[i] = offset;
	offset += descr->sizeof_register[i];
	gdb_assert (MAX_REGISTER_SIZE >= descr->sizeof_register[i]);
      }
    /* Set the real size of the register cache buffer.  */
    descr->sizeof_cooked_registers = offset;
  }

  /* FIXME: cagney/2002-05-22: Should only need to allocate space for
     the raw registers.  Unfortunately some code still accesses the
     register array directly using the global registers[].  Until that
     code has been purged, play safe and over allocating the register
     buffer.  Ulgh!  */
  descr->sizeof_raw_registers = descr->sizeof_cooked_registers;

  return descr;
}

static struct regcache_descr *
regcache_descr (struct gdbarch *gdbarch)
{
  return gdbarch_data (gdbarch, regcache_descr_handle);
}

/* Utility functions returning useful register attributes stored in
   the regcache descr.  */

struct type *
register_type (struct gdbarch *gdbarch, int regnum)
{
  struct regcache_descr *descr = regcache_descr (gdbarch);
  gdb_assert (regnum >= 0 && regnum < descr->nr_cooked_registers);
  return descr->register_type[regnum];
}

/* Utility functions returning useful register attributes stored in
   the regcache descr.  */

int
register_size (struct gdbarch *gdbarch, int regnum)
{
  struct regcache_descr *descr = regcache_descr (gdbarch);
  int size;
  gdb_assert (regnum >= 0
	      && regnum < (gdbarch_num_regs (current_gdbarch)
			   + gdbarch_num_pseudo_regs (current_gdbarch)));
  size = descr->sizeof_register[regnum];
  return size;
}

/* The register cache for storing raw register values.  */

struct regcache
{
  struct regcache_descr *descr;
  /* The register buffers.  A read-only register cache can hold the
     full [0 .. gdbarch_num_regs + gdbarch_num_pseudo_regs) while a read/write
     register cache can only hold [0 .. gdbarch_num_regs).  */
  gdb_byte *registers;
  /* Register cache status:
     register_valid_p[REG] == 0 if REG value is not in the cache
                            > 0 if REG value is in the cache
                            < 0 if REG value is permanently unavailable */
  signed char *register_valid_p;
  /* Is this a read-only cache?  A read-only cache is used for saving
     the target's register state (e.g, across an inferior function
     call or just before forcing a function return).  A read-only
     cache can only be updated via the methods regcache_dup() and
     regcache_cpy().  The actual contents are determined by the
     reggroup_save and reggroup_restore methods.  */
  int readonly_p;
  /* If this is a read-write cache, which thread's registers is
     it connected to?  */
  ptid_t ptid;
};

struct regcache *
regcache_xmalloc (struct gdbarch *gdbarch)
{
  struct regcache_descr *descr;
  struct regcache *regcache;
  gdb_assert (gdbarch != NULL);
  descr = regcache_descr (gdbarch);
  regcache = XMALLOC (struct regcache);
  regcache->descr = descr;
  regcache->registers
    = XCALLOC (descr->sizeof_raw_registers, gdb_byte);
  regcache->register_valid_p
    = XCALLOC (descr->sizeof_raw_register_valid_p, gdb_byte);
  regcache->readonly_p = 1;
  regcache->ptid = minus_one_ptid;
  return regcache;
}

void
regcache_xfree (struct regcache *regcache)
{
  if (regcache == NULL)
    return;
  xfree (regcache->registers);
  xfree (regcache->register_valid_p);
  xfree (regcache);
}

static void
do_regcache_xfree (void *data)
{
  regcache_xfree (data);
}

struct cleanup *
make_cleanup_regcache_xfree (struct regcache *regcache)
{
  return make_cleanup (do_regcache_xfree, regcache);
}

/* Return REGCACHE's architecture.  */

struct gdbarch *
get_regcache_arch (const struct regcache *regcache)
{
  return regcache->descr->gdbarch;
}

/* Return  a pointer to register REGNUM's buffer cache.  */

static gdb_byte *
register_buffer (const struct regcache *regcache, int regnum)
{
  return regcache->registers + regcache->descr->register_offset[regnum];
}

void
regcache_save (struct regcache *dst, regcache_cooked_read_ftype *cooked_read,
	       void *src)
{
  struct gdbarch *gdbarch = dst->descr->gdbarch;
  gdb_byte buf[MAX_REGISTER_SIZE];
  int regnum;
  /* The DST should be `read-only', if it wasn't then the save would
     end up trying to write the register values back out to the
     target.  */
  gdb_assert (dst->readonly_p);
  /* Clear the dest.  */
  memset (dst->registers, 0, dst->descr->sizeof_cooked_registers);
  memset (dst->register_valid_p, 0, dst->descr->sizeof_cooked_register_valid_p);
  /* Copy over any registers (identified by their membership in the
     save_reggroup) and mark them as valid.  The full [0 .. gdbarch_num_regs +
     gdbarch_num_pseudo_regs) range is checked since some architectures need
     to save/restore `cooked' registers that live in memory.  */
  for (regnum = 0; regnum < dst->descr->nr_cooked_registers; regnum++)
    {
      if (gdbarch_register_reggroup_p (gdbarch, regnum, save_reggroup))
	{
	  int valid = cooked_read (src, regnum, buf);
	  if (valid)
	    {
	      memcpy (register_buffer (dst, regnum), buf,
		      register_size (gdbarch, regnum));
	      dst->register_valid_p[regnum] = 1;
	    }
	}
    }
}

void
regcache_restore (struct regcache *dst,
		  regcache_cooked_read_ftype *cooked_read,
		  void *cooked_read_context)
{
  struct gdbarch *gdbarch = dst->descr->gdbarch;
  gdb_byte buf[MAX_REGISTER_SIZE];
  int regnum;
  /* The dst had better not be read-only.  If it is, the `restore'
     doesn't make much sense.  */
  gdb_assert (!dst->readonly_p);
  /* Copy over any registers, being careful to only restore those that
     were both saved and need to be restored.  The full [0 .. gdbarch_num_regs
     + gdbarch_num_pseudo_regs) range is checked since some architectures need
     to save/restore `cooked' registers that live in memory.  */
  for (regnum = 0; regnum < dst->descr->nr_cooked_registers; regnum++)
    {
      if (gdbarch_register_reggroup_p (gdbarch, regnum, restore_reggroup))
	{
	  int valid = cooked_read (cooked_read_context, regnum, buf);
	  if (valid)
	    regcache_cooked_write (dst, regnum, buf);
	}
    }
}

static int
do_cooked_read (void *src, int regnum, gdb_byte *buf)
{
  struct regcache *regcache = src;
  if (!regcache->register_valid_p[regnum] && regcache->readonly_p)
    /* Don't even think about fetching a register from a read-only
       cache when the register isn't yet valid.  There isn't a target
       from which the register value can be fetched.  */
    return 0;
  regcache_cooked_read (regcache, regnum, buf);
  return 1;
}


void
regcache_cpy (struct regcache *dst, struct regcache *src)
{
  int i;
  gdb_byte *buf;
  gdb_assert (src != NULL && dst != NULL);
  gdb_assert (src->descr->gdbarch == dst->descr->gdbarch);
  gdb_assert (src != dst);
  gdb_assert (src->readonly_p || dst->readonly_p);
  if (!src->readonly_p)
    regcache_save (dst, do_cooked_read, src);
  else if (!dst->readonly_p)
    regcache_restore (dst, do_cooked_read, src);
  else
    regcache_cpy_no_passthrough (dst, src);
}

void
regcache_cpy_no_passthrough (struct regcache *dst, struct regcache *src)
{
  int i;
  gdb_assert (src != NULL && dst != NULL);
  gdb_assert (src->descr->gdbarch == dst->descr->gdbarch);
  /* NOTE: cagney/2002-05-17: Don't let the caller do a no-passthrough
     move of data into the current regcache.  Doing this would be
     silly - it would mean that valid_p would be completely invalid.  */
  gdb_assert (dst->readonly_p);
  memcpy (dst->registers, src->registers, dst->descr->sizeof_raw_registers);
  memcpy (dst->register_valid_p, src->register_valid_p,
	  dst->descr->sizeof_raw_register_valid_p);
}

struct regcache *
regcache_dup (struct regcache *src)
{
  struct regcache *newbuf;
  newbuf = regcache_xmalloc (src->descr->gdbarch);
  regcache_cpy (newbuf, src);
  return newbuf;
}

struct regcache *
regcache_dup_no_passthrough (struct regcache *src)
{
  struct regcache *newbuf;
  newbuf = regcache_xmalloc (src->descr->gdbarch);
  regcache_cpy_no_passthrough (newbuf, src);
  return newbuf;
}

int
regcache_valid_p (const struct regcache *regcache, int regnum)
{
  gdb_assert (regcache != NULL);
  gdb_assert (regnum >= 0);
  if (regcache->readonly_p)
    gdb_assert (regnum < regcache->descr->nr_cooked_registers);
  else
    gdb_assert (regnum < regcache->descr->nr_raw_registers);

  return regcache->register_valid_p[regnum];
}

void
regcache_invalidate (struct regcache *regcache, int regnum)
{
  gdb_assert (regcache != NULL);
  gdb_assert (regnum >= 0);
  gdb_assert (!regcache->readonly_p);
  gdb_assert (regnum < regcache->descr->nr_raw_registers);
  regcache->register_valid_p[regnum] = 0;
}


/* Global structure containing the current regcache.  */
/* FIXME: cagney/2002-05-11: The two global arrays registers[] and
   deprecated_register_valid[] currently point into this structure.  */
static struct regcache *current_regcache;

/* NOTE: this is a write-through cache.  There is no "dirty" bit for
   recording if the register values have been changed (eg. by the
   user).  Therefore all registers must be written back to the
   target when appropriate.  */

struct regcache *get_thread_regcache (ptid_t ptid)
{
  /* NOTE: uweigand/2007-05-05:  We need to detect the thread's
     current architecture at this point.  */
  struct gdbarch *thread_gdbarch = current_gdbarch;

  if (current_regcache && ptid_equal (current_regcache->ptid, ptid)
      && get_regcache_arch (current_regcache) == thread_gdbarch)
    return current_regcache;

  if (current_regcache)
    regcache_xfree (current_regcache);

  current_regcache = regcache_xmalloc (thread_gdbarch);
  current_regcache->readonly_p = 0;
  current_regcache->ptid = ptid;

  return current_regcache;
}

struct regcache *get_current_regcache (void)
{
  return get_thread_regcache (inferior_ptid);
}


/* Observer for the target_changed event.  */

void
regcache_observer_target_changed (struct target_ops *target)
{
  registers_changed ();
}

/* Low level examining and depositing of registers.

   The caller is responsible for making sure that the inferior is
   stopped before calling the fetching routines, or it will get
   garbage.  (a change from GDB version 3, in which the caller got the
   value from the last stop).  */

/* REGISTERS_CHANGED ()

   Indicate that registers may have changed, so invalidate the cache.  */

void
registers_changed (void)
{
  int i;

  regcache_xfree (current_regcache);
  current_regcache = NULL;

  /* Force cleanup of any alloca areas if using C alloca instead of
     a builtin alloca.  This particular call is used to clean up
     areas allocated by low level target code which may build up
     during lengthy interactions between gdb and the target before
     gdb gives control to the user (ie watchpoints).  */
  alloca (0);
}


void
regcache_raw_read (struct regcache *regcache, int regnum, gdb_byte *buf)
{
  gdb_assert (regcache != NULL && buf != NULL);
  gdb_assert (regnum >= 0 && regnum < regcache->descr->nr_raw_registers);
  /* Make certain that the register cache is up-to-date with respect
     to the current thread.  This switching shouldn't be necessary
     only there is still only one target side register cache.  Sigh!
     On the bright side, at least there is a regcache object.  */
  if (!regcache->readonly_p)
    {
      if (!regcache_valid_p (regcache, regnum))
	{
	  struct cleanup *old_chain = save_inferior_ptid ();
	  inferior_ptid = regcache->ptid;
	  target_fetch_registers (regcache, regnum);
	  do_cleanups (old_chain);
	}
#if 0
      /* FIXME: cagney/2004-08-07: At present a number of targets
	 forget (or didn't know that they needed) to set this leading to
	 panics.  Also is the problem that targets need to indicate
	 that a register is in one of the possible states: valid,
	 undefined, unknown.  The last of which isn't yet
	 possible.  */
      gdb_assert (regcache_valid_p (regcache, regnum));
#endif
    }
  /* Copy the value directly into the register cache.  */
  memcpy (buf, register_buffer (regcache, regnum),
	  regcache->descr->sizeof_register[regnum]);
}

void
regcache_raw_read_signed (struct regcache *regcache, int regnum, LONGEST *val)
{
  gdb_byte *buf;
  gdb_assert (regcache != NULL);
  gdb_assert (regnum >= 0 && regnum < regcache->descr->nr_raw_registers);
  buf = alloca (regcache->descr->sizeof_register[regnum]);
  regcache_raw_read (regcache, regnum, buf);
  (*val) = extract_signed_integer (buf,
				   regcache->descr->sizeof_register[regnum]);
}

void
regcache_raw_read_unsigned (struct regcache *regcache, int regnum,
			    ULONGEST *val)
{
  gdb_byte *buf;
  gdb_assert (regcache != NULL);
  gdb_assert (regnum >= 0 && regnum < regcache->descr->nr_raw_registers);
  buf = alloca (regcache->descr->sizeof_register[regnum]);
  regcache_raw_read (regcache, regnum, buf);
  (*val) = extract_unsigned_integer (buf,
				     regcache->descr->sizeof_register[regnum]);
}

void
regcache_raw_write_signed (struct regcache *regcache, int regnum, LONGEST val)
{
  void *buf;
  gdb_assert (regcache != NULL);
  gdb_assert (regnum >=0 && regnum < regcache->descr->nr_raw_registers);
  buf = alloca (regcache->descr->sizeof_register[regnum]);
  store_signed_integer (buf, regcache->descr->sizeof_register[regnum], val);
  regcache_raw_write (regcache, regnum, buf);
}

void
regcache_raw_write_unsigned (struct regcache *regcache, int regnum,
			     ULONGEST val)
{
  void *buf;
  gdb_assert (regcache != NULL);
  gdb_assert (regnum >=0 && regnum < regcache->descr->nr_raw_registers);
  buf = alloca (regcache->descr->sizeof_register[regnum]);
  store_unsigned_integer (buf, regcache->descr->sizeof_register[regnum], val);
  regcache_raw_write (regcache, regnum, buf);
}

void
regcache_cooked_read (struct regcache *regcache, int regnum, gdb_byte *buf)
{
  gdb_assert (regnum >= 0);
  gdb_assert (regnum < regcache->descr->nr_cooked_registers);
  if (regnum < regcache->descr->nr_raw_registers)
    regcache_raw_read (regcache, regnum, buf);
  else if (regcache->readonly_p
	   && regnum < regcache->descr->nr_cooked_registers
	   && regcache->register_valid_p[regnum])
    /* Read-only register cache, perhaps the cooked value was cached?  */
    memcpy (buf, register_buffer (regcache, regnum),
	    regcache->descr->sizeof_register[regnum]);
  else
    gdbarch_pseudo_register_read (regcache->descr->gdbarch, regcache,
				  regnum, buf);
}

void
regcache_cooked_read_signed (struct regcache *regcache, int regnum,
			     LONGEST *val)
{
  gdb_byte *buf;
  gdb_assert (regcache != NULL);
  gdb_assert (regnum >= 0 && regnum < regcache->descr->nr_cooked_registers);
  buf = alloca (regcache->descr->sizeof_register[regnum]);
  regcache_cooked_read (regcache, regnum, buf);
  (*val) = extract_signed_integer (buf,
				   regcache->descr->sizeof_register[regnum]);
}

void
regcache_cooked_read_unsigned (struct regcache *regcache, int regnum,
			       ULONGEST *val)
{
  gdb_byte *buf;
  gdb_assert (regcache != NULL);
  gdb_assert (regnum >= 0 && regnum < regcache->descr->nr_cooked_registers);
  buf = alloca (regcache->descr->sizeof_register[regnum]);
  regcache_cooked_read (regcache, regnum, buf);
  (*val) = extract_unsigned_integer (buf,
				     regcache->descr->sizeof_register[regnum]);
}

void
regcache_cooked_write_signed (struct regcache *regcache, int regnum,
			      LONGEST val)
{
  void *buf;
  gdb_assert (regcache != NULL);
  gdb_assert (regnum >=0 && regnum < regcache->descr->nr_cooked_registers);
  buf = alloca (regcache->descr->sizeof_register[regnum]);
  store_signed_integer (buf, regcache->descr->sizeof_register[regnum], val);
  regcache_cooked_write (regcache, regnum, buf);
}

void
regcache_cooked_write_unsigned (struct regcache *regcache, int regnum,
				ULONGEST val)
{
  void *buf;
  gdb_assert (regcache != NULL);
  gdb_assert (regnum >=0 && regnum < regcache->descr->nr_cooked_registers);
  buf = alloca (regcache->descr->sizeof_register[regnum]);
  store_unsigned_integer (buf, regcache->descr->sizeof_register[regnum], val);
  regcache_cooked_write (regcache, regnum, buf);
}

void
regcache_raw_write (struct regcache *regcache, int regnum,
		    const gdb_byte *buf)
{
  struct cleanup *old_chain;

  gdb_assert (regcache != NULL && buf != NULL);
  gdb_assert (regnum >= 0 && regnum < regcache->descr->nr_raw_registers);
  gdb_assert (!regcache->readonly_p);

  /* On the sparc, writing %g0 is a no-op, so we don't even want to
     change the registers array if something writes to this register.  */
  if (gdbarch_cannot_store_register (current_gdbarch, regnum))
    return;

  /* If we have a valid copy of the register, and new value == old
     value, then don't bother doing the actual store. */
  if (regcache_valid_p (regcache, regnum)
      && (memcmp (register_buffer (regcache, regnum), buf,
		  regcache->descr->sizeof_register[regnum]) == 0))
    return;

  old_chain = save_inferior_ptid ();
  inferior_ptid = regcache->ptid;

  target_prepare_to_store (regcache);
  memcpy (register_buffer (regcache, regnum), buf,
	  regcache->descr->sizeof_register[regnum]);
  regcache->register_valid_p[regnum] = 1;
  target_store_registers (regcache, regnum);

  do_cleanups (old_chain);
}

void
regcache_cooked_write (struct regcache *regcache, int regnum,
		       const gdb_byte *buf)
{
  gdb_assert (regnum >= 0);
  gdb_assert (regnum < regcache->descr->nr_cooked_registers);
  if (regnum < regcache->descr->nr_raw_registers)
    regcache_raw_write (regcache, regnum, buf);
  else
    gdbarch_pseudo_register_write (regcache->descr->gdbarch, regcache,
				   regnum, buf);
}

/* Perform a partial register transfer using a read, modify, write
   operation.  */

typedef void (regcache_read_ftype) (struct regcache *regcache, int regnum,
				    void *buf);
typedef void (regcache_write_ftype) (struct regcache *regcache, int regnum,
				     const void *buf);

static void
regcache_xfer_part (struct regcache *regcache, int regnum,
		    int offset, int len, void *in, const void *out,
		    void (*read) (struct regcache *regcache, int regnum,
				  gdb_byte *buf),
		    void (*write) (struct regcache *regcache, int regnum,
				   const gdb_byte *buf))
{
  struct regcache_descr *descr = regcache->descr;
  gdb_byte reg[MAX_REGISTER_SIZE];
  gdb_assert (offset >= 0 && offset <= descr->sizeof_register[regnum]);
  gdb_assert (len >= 0 && offset + len <= descr->sizeof_register[regnum]);
  /* Something to do?  */
  if (offset + len == 0)
    return;
  /* Read (when needed) ... */
  if (in != NULL
      || offset > 0
      || offset + len < descr->sizeof_register[regnum])
    {
      gdb_assert (read != NULL);
      read (regcache, regnum, reg);
    }
  /* ... modify ... */
  if (in != NULL)
    memcpy (in, reg + offset, len);
  if (out != NULL)
    memcpy (reg + offset, out, len);
  /* ... write (when needed).  */
  if (out != NULL)
    {
      gdb_assert (write != NULL);
      write (regcache, regnum, reg);
    }
}

void
regcache_raw_read_part (struct regcache *regcache, int regnum,
			int offset, int len, gdb_byte *buf)
{
  struct regcache_descr *descr = regcache->descr;
  gdb_assert (regnum >= 0 && regnum < descr->nr_raw_registers);
  regcache_xfer_part (regcache, regnum, offset, len, buf, NULL,
		      regcache_raw_read, regcache_raw_write);
}

void
regcache_raw_write_part (struct regcache *regcache, int regnum,
			 int offset, int len, const gdb_byte *buf)
{
  struct regcache_descr *descr = regcache->descr;
  gdb_assert (regnum >= 0 && regnum < descr->nr_raw_registers);
  regcache_xfer_part (regcache, regnum, offset, len, NULL, buf,
		      regcache_raw_read, regcache_raw_write);
}

void
regcache_cooked_read_part (struct regcache *regcache, int regnum,
			   int offset, int len, gdb_byte *buf)
{
  struct regcache_descr *descr = regcache->descr;
  gdb_assert (regnum >= 0 && regnum < descr->nr_cooked_registers);
  regcache_xfer_part (regcache, regnum, offset, len, buf, NULL,
		      regcache_cooked_read, regcache_cooked_write);
}

void
regcache_cooked_write_part (struct regcache *regcache, int regnum,
			    int offset, int len, const gdb_byte *buf)
{
  struct regcache_descr *descr = regcache->descr;
  gdb_assert (regnum >= 0 && regnum < descr->nr_cooked_registers);
  regcache_xfer_part (regcache, regnum, offset, len, NULL, buf,
		      regcache_cooked_read, regcache_cooked_write);
}

/* Hack to keep code that view the register buffer as raw bytes
   working.  */

int
register_offset_hack (struct gdbarch *gdbarch, int regnum)
{
  struct regcache_descr *descr = regcache_descr (gdbarch);
  gdb_assert (regnum >= 0 && regnum < descr->nr_cooked_registers);
  return descr->register_offset[regnum];
}


/* Supply register REGNUM, whose contents are stored in BUF, to REGCACHE.  */

void
regcache_raw_supply (struct regcache *regcache, int regnum, const void *buf)
{
  void *regbuf;
  size_t size;

  gdb_assert (regcache != NULL);
  gdb_assert (regnum >= 0 && regnum < regcache->descr->nr_raw_registers);
  gdb_assert (!regcache->readonly_p);

  regbuf = register_buffer (regcache, regnum);
  size = regcache->descr->sizeof_register[regnum];

  if (buf)
    memcpy (regbuf, buf, size);
  else
    memset (regbuf, 0, size);

  /* Mark the register as cached.  */
  regcache->register_valid_p[regnum] = 1;
}

/* Collect register REGNUM from REGCACHE and store its contents in BUF.  */

void
regcache_raw_collect (const struct regcache *regcache, int regnum, void *buf)
{
  const void *regbuf;
  size_t size;

  gdb_assert (regcache != NULL && buf != NULL);
  gdb_assert (regnum >= 0 && regnum < regcache->descr->nr_raw_registers);

  regbuf = register_buffer (regcache, regnum);
  size = regcache->descr->sizeof_register[regnum];
  memcpy (buf, regbuf, size);
}


/* read_pc, write_pc, etc.  Special handling for register PC.  */

/* NOTE: cagney/2001-02-18: The functions read_pc_pid(), read_pc() and
   read_sp(), will eventually be replaced by per-frame methods.
   Instead of relying on the global INFERIOR_PTID, they will use the
   contextual information provided by the FRAME.  These functions do
   not belong in the register cache.  */

/* NOTE: cagney/2003-06-07: The functions generic_target_write_pc(),
   write_pc_pid() and write_pc(), all need to be replaced by something
   that does not rely on global state.  But what?  */

CORE_ADDR
read_pc_pid (ptid_t ptid)
{
  struct regcache *regcache = get_thread_regcache (ptid);
  struct gdbarch *gdbarch = get_regcache_arch (regcache);

  CORE_ADDR pc_val;

  if (gdbarch_read_pc_p (gdbarch))
    pc_val = gdbarch_read_pc (gdbarch, regcache);
  /* Else use per-frame method on get_current_frame.  */
  else if (gdbarch_pc_regnum (current_gdbarch) >= 0)
    {
      ULONGEST raw_val;
      regcache_cooked_read_unsigned (regcache,
				     gdbarch_pc_regnum (current_gdbarch),
				     &raw_val);
      pc_val = gdbarch_addr_bits_remove (current_gdbarch, raw_val);
    }
  else
    internal_error (__FILE__, __LINE__, _("read_pc_pid: Unable to find PC"));

  return pc_val;
}

CORE_ADDR
read_pc (void)
{
  return read_pc_pid (inferior_ptid);
}

void
write_pc_pid (CORE_ADDR pc, ptid_t ptid)
{
  struct regcache *regcache = get_thread_regcache (ptid);
  struct gdbarch *gdbarch = get_regcache_arch (regcache);

  if (gdbarch_write_pc_p (gdbarch))
    gdbarch_write_pc (gdbarch, regcache, pc);
  else if (gdbarch_pc_regnum (current_gdbarch) >= 0)
    regcache_cooked_write_unsigned (regcache,
				    gdbarch_pc_regnum (current_gdbarch), pc);
  else
    internal_error (__FILE__, __LINE__,
		    _("write_pc_pid: Unable to update PC"));
}

void
write_pc (CORE_ADDR pc)
{
  write_pc_pid (pc, inferior_ptid);
}


static void
reg_flush_command (char *command, int from_tty)
{
  /* Force-flush the register cache.  */
  registers_changed ();
  if (from_tty)
    printf_filtered (_("Register cache flushed.\n"));
}

static void
dump_endian_bytes (struct ui_file *file, enum bfd_endian endian,
		   const unsigned char *buf, long len)
{
  int i;
  switch (endian)
    {
    case BFD_ENDIAN_BIG:
      for (i = 0; i < len; i++)
	fprintf_unfiltered (file, "%02x", buf[i]);
      break;
    case BFD_ENDIAN_LITTLE:
      for (i = len - 1; i >= 0; i--)
	fprintf_unfiltered (file, "%02x", buf[i]);
      break;
    default:
      internal_error (__FILE__, __LINE__, _("Bad switch"));
    }
}

enum regcache_dump_what
{
  regcache_dump_none, regcache_dump_raw, regcache_dump_cooked, regcache_dump_groups
};

static void
regcache_dump (struct regcache *regcache, struct ui_file *file,
	       enum regcache_dump_what what_to_dump)
{
  struct cleanup *cleanups = make_cleanup (null_cleanup, NULL);
  struct gdbarch *gdbarch = regcache->descr->gdbarch;
  int regnum;
  int footnote_nr = 0;
  int footnote_register_size = 0;
  int footnote_register_offset = 0;
  int footnote_register_type_name_null = 0;
  long register_offset = 0;
  unsigned char buf[MAX_REGISTER_SIZE];

#if 0
  fprintf_unfiltered (file, "nr_raw_registers %d\n",
		      regcache->descr->nr_raw_registers);
  fprintf_unfiltered (file, "nr_cooked_registers %d\n",
		      regcache->descr->nr_cooked_registers);
  fprintf_unfiltered (file, "sizeof_raw_registers %ld\n",
		      regcache->descr->sizeof_raw_registers);
  fprintf_unfiltered (file, "sizeof_raw_register_valid_p %ld\n",
		      regcache->descr->sizeof_raw_register_valid_p);
  fprintf_unfiltered (file, "gdbarch_num_regs %d\n", 
		      gdbarch_num_regs (current_gdbarch));
  fprintf_unfiltered (file, "gdbarch_num_pseudo_regs %d\n",
		      gdbarch_num_pseudo_regs (current_gdbarch));
#endif

  gdb_assert (regcache->descr->nr_cooked_registers
	      == (gdbarch_num_regs (current_gdbarch)
		  + gdbarch_num_pseudo_regs (current_gdbarch)));

  for (regnum = -1; regnum < regcache->descr->nr_cooked_registers; regnum++)
    {
      /* Name.  */
      if (regnum < 0)
	fprintf_unfiltered (file, " %-10s", "Name");
      else
	{
	  const char *p = gdbarch_register_name (current_gdbarch, regnum);
	  if (p == NULL)
	    p = "";
	  else if (p[0] == '\0')
	    p = "''";
	  fprintf_unfiltered (file, " %-10s", p);
	}

      /* Number.  */
      if (regnum < 0)
	fprintf_unfiltered (file, " %4s", "Nr");
      else
	fprintf_unfiltered (file, " %4d", regnum);

      /* Relative number.  */
      if (regnum < 0)
	fprintf_unfiltered (file, " %4s", "Rel");
      else if (regnum < gdbarch_num_regs (current_gdbarch))
	fprintf_unfiltered (file, " %4d", regnum);
      else
	fprintf_unfiltered (file, " %4d",
			    (regnum - gdbarch_num_regs (current_gdbarch)));

      /* Offset.  */
      if (regnum < 0)
	fprintf_unfiltered (file, " %6s  ", "Offset");
      else
	{
	  fprintf_unfiltered (file, " %6ld",
			      regcache->descr->register_offset[regnum]);
	  if (register_offset != regcache->descr->register_offset[regnum]
	      || (regnum > 0
		  && (regcache->descr->register_offset[regnum]
		      != (regcache->descr->register_offset[regnum - 1]
			  + regcache->descr->sizeof_register[regnum - 1])))
	      )
	    {
	      if (!footnote_register_offset)
		footnote_register_offset = ++footnote_nr;
	      fprintf_unfiltered (file, "*%d", footnote_register_offset);
	    }
	  else
	    fprintf_unfiltered (file, "  ");
	  register_offset = (regcache->descr->register_offset[regnum]
			     + regcache->descr->sizeof_register[regnum]);
	}

      /* Size.  */
      if (regnum < 0)
	fprintf_unfiltered (file, " %5s ", "Size");
      else
	fprintf_unfiltered (file, " %5ld",
			    regcache->descr->sizeof_register[regnum]);

      /* Type.  */
      {
	const char *t;
	if (regnum < 0)
	  t = "Type";
	else
	  {
	    static const char blt[] = "builtin_type";
	    t = TYPE_NAME (register_type (regcache->descr->gdbarch, regnum));
	    if (t == NULL)
	      {
		char *n;
		if (!footnote_register_type_name_null)
		  footnote_register_type_name_null = ++footnote_nr;
		n = xstrprintf ("*%d", footnote_register_type_name_null);
		make_cleanup (xfree, n);
		t = n;
	      }
	    /* Chop a leading builtin_type.  */
	    if (strncmp (t, blt, strlen (blt)) == 0)
	      t += strlen (blt);
	  }
	fprintf_unfiltered (file, " %-15s", t);
      }

      /* Leading space always present.  */
      fprintf_unfiltered (file, " ");

      /* Value, raw.  */
      if (what_to_dump == regcache_dump_raw)
	{
	  if (regnum < 0)
	    fprintf_unfiltered (file, "Raw value");
	  else if (regnum >= regcache->descr->nr_raw_registers)
	    fprintf_unfiltered (file, "<cooked>");
	  else if (!regcache_valid_p (regcache, regnum))
	    fprintf_unfiltered (file, "<invalid>");
	  else
	    {
	      regcache_raw_read (regcache, regnum, buf);
	      fprintf_unfiltered (file, "0x");
	      dump_endian_bytes (file,
				 gdbarch_byte_order (current_gdbarch), buf,
				 regcache->descr->sizeof_register[regnum]);
	    }
	}

      /* Value, cooked.  */
      if (what_to_dump == regcache_dump_cooked)
	{
	  if (regnum < 0)
	    fprintf_unfiltered (file, "Cooked value");
	  else
	    {
	      regcache_cooked_read (regcache, regnum, buf);
	      fprintf_unfiltered (file, "0x");
	      dump_endian_bytes (file,
				 gdbarch_byte_order (current_gdbarch), buf,
				 regcache->descr->sizeof_register[regnum]);
	    }
	}

      /* Group members.  */
      if (what_to_dump == regcache_dump_groups)
	{
	  if (regnum < 0)
	    fprintf_unfiltered (file, "Groups");
	  else
	    {
	      const char *sep = "";
	      struct reggroup *group;
	      for (group = reggroup_next (gdbarch, NULL);
		   group != NULL;
		   group = reggroup_next (gdbarch, group))
		{
		  if (gdbarch_register_reggroup_p (gdbarch, regnum, group))
		    {
		      fprintf_unfiltered (file, "%s%s", sep, reggroup_name (group));
		      sep = ",";
		    }
		}
	    }
	}

      fprintf_unfiltered (file, "\n");
    }

  if (footnote_register_size)
    fprintf_unfiltered (file, "*%d: Inconsistent register sizes.\n",
			footnote_register_size);
  if (footnote_register_offset)
    fprintf_unfiltered (file, "*%d: Inconsistent register offsets.\n",
			footnote_register_offset);
  if (footnote_register_type_name_null)
    fprintf_unfiltered (file, 
			"*%d: Register type's name NULL.\n",
			footnote_register_type_name_null);
  do_cleanups (cleanups);
}

static void
regcache_print (char *args, enum regcache_dump_what what_to_dump)
{
  if (args == NULL)
    regcache_dump (get_current_regcache (), gdb_stdout, what_to_dump);
  else
    {
      struct ui_file *file = gdb_fopen (args, "w");
      if (file == NULL)
	perror_with_name (_("maintenance print architecture"));
      regcache_dump (get_current_regcache (), file, what_to_dump);
      ui_file_delete (file);
    }
}

static void
maintenance_print_registers (char *args, int from_tty)
{
  regcache_print (args, regcache_dump_none);
}

static void
maintenance_print_raw_registers (char *args, int from_tty)
{
  regcache_print (args, regcache_dump_raw);
}

static void
maintenance_print_cooked_registers (char *args, int from_tty)
{
  regcache_print (args, regcache_dump_cooked);
}

static void
maintenance_print_register_groups (char *args, int from_tty)
{
  regcache_print (args, regcache_dump_groups);
}

extern initialize_file_ftype _initialize_regcache; /* -Wmissing-prototype */

void
_initialize_regcache (void)
{
  regcache_descr_handle = gdbarch_data_register_post_init (init_regcache_descr);

  observer_attach_target_changed (regcache_observer_target_changed);

  add_com ("flushregs", class_maintenance, reg_flush_command,
	   _("Force gdb to flush its register cache (maintainer command)"));

  add_cmd ("registers", class_maintenance, maintenance_print_registers, _("\
Print the internal register configuration.\n\
Takes an optional file parameter."), &maintenanceprintlist);
  add_cmd ("raw-registers", class_maintenance,
	   maintenance_print_raw_registers, _("\
Print the internal register configuration including raw values.\n\
Takes an optional file parameter."), &maintenanceprintlist);
  add_cmd ("cooked-registers", class_maintenance,
	   maintenance_print_cooked_registers, _("\
Print the internal register configuration including cooked values.\n\
Takes an optional file parameter."), &maintenanceprintlist);
  add_cmd ("register-groups", class_maintenance,
	   maintenance_print_register_groups, _("\
Print the internal register configuration including each register's group.\n\
Takes an optional file parameter."),
	   &maintenanceprintlist);

}