summaryrefslogtreecommitdiffstats
path: root/binutils-2.25/opcodes/sparc-dis.c
blob: 9f0b96ee17e1dc382d6a0a8b91985b6304cfca4f (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
/* Print SPARC instructions.
   Copyright (C) 1989-2014 Free Software Foundation, Inc.

   This file is part of the GNU opcodes library.

   This library 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, or (at your option)
   any later version.

   It 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, write to the Free Software
   Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
   MA 02110-1301, USA.  */

#include "sysdep.h"
#include <stdio.h>
#include "opcode/sparc.h"
#include "dis-asm.h"
#include "libiberty.h"
#include "opintl.h"

/* Bitmask of v9 architectures.  */
#define MASK_V9 ((1 << SPARC_OPCODE_ARCH_V9) \
		 | (1 << SPARC_OPCODE_ARCH_V9A) \
		 | (1 << SPARC_OPCODE_ARCH_V9B))
/* 1 if INSN is for v9 only.  */
#define V9_ONLY_P(insn) (! ((insn)->architecture & ~MASK_V9))
/* 1 if INSN is for v9.  */
#define V9_P(insn) (((insn)->architecture & MASK_V9) != 0)

/* The sorted opcode table.  */
static const sparc_opcode **sorted_opcodes;

/* For faster lookup, after insns are sorted they are hashed.  */
/* ??? I think there is room for even more improvement.  */

#define HASH_SIZE 256
/* It is important that we only look at insn code bits as that is how the
   opcode table is hashed.  OPCODE_BITS is a table of valid bits for each
   of the main types (0,1,2,3).  */
static int opcode_bits[4] = { 0x01c00000, 0x0, 0x01f80000, 0x01f80000 };
#define HASH_INSN(INSN) \
  ((((INSN) >> 24) & 0xc0) | (((INSN) & opcode_bits[((INSN) >> 30) & 3]) >> 19))
typedef struct sparc_opcode_hash
{
  struct sparc_opcode_hash *next;
  const sparc_opcode *opcode;
} sparc_opcode_hash;

static sparc_opcode_hash *opcode_hash_table[HASH_SIZE];

/* Sign-extend a value which is N bits long.  */
#define	SEX(value, bits) \
	((((int)(value)) << ((8 * sizeof (int)) - bits))	\
			 >> ((8 * sizeof (int)) - bits) )

static  char *reg_names[] =
{ "g0", "g1", "g2", "g3", "g4", "g5", "g6", "g7",
  "o0", "o1", "o2", "o3", "o4", "o5", "sp", "o7",
  "l0", "l1", "l2", "l3", "l4", "l5", "l6", "l7",
  "i0", "i1", "i2", "i3", "i4", "i5", "fp", "i7",
  "f0", "f1", "f2", "f3", "f4", "f5", "f6", "f7",
  "f8", "f9", "f10", "f11", "f12", "f13", "f14", "f15",
  "f16", "f17", "f18", "f19", "f20", "f21", "f22", "f23",
  "f24", "f25", "f26", "f27", "f28", "f29", "f30", "f31",
  "f32", "f33", "f34", "f35", "f36", "f37", "f38", "f39",
  "f40", "f41", "f42", "f43", "f44", "f45", "f46", "f47",
  "f48", "f49", "f50", "f51", "f52", "f53", "f54", "f55",
  "f56", "f57", "f58", "f59", "f60", "f61", "f62", "f63",
/* psr, wim, tbr, fpsr, cpsr are v8 only.  */
  "y", "psr", "wim", "tbr", "pc", "npc", "fpsr", "cpsr"
};

#define	freg_names	(&reg_names[4 * 8])

/* These are ordered according to there register number in
   rdpr and wrpr insns.  */
static char *v9_priv_reg_names[] =
{
  "tpc", "tnpc", "tstate", "tt", "tick", "tba", "pstate", "tl",
  "pil", "cwp", "cansave", "canrestore", "cleanwin", "otherwin",
  "wstate", "fq", "gl"
  /* "ver" - special cased */
};

/* These are ordered according to there register number in
   rdhpr and wrhpr insns.  */
static char *v9_hpriv_reg_names[] =
{
  "hpstate", "htstate", "resv2", "hintp", "resv4", "htba", "hver",
  "resv7", "resv8", "resv9", "resv10", "resv11", "resv12", "resv13", 
  "resv14", "resv15", "resv16", "resv17", "resv18", "resv19", "resv20",
  "resv21", "resv22", "resv23", "resv24", "resv25", "resv26", "resv27",
  "hstick_offset", "hstick_enable", "resv30", "hstick_cmpr"
};

/* These are ordered according to there register number in
   rd and wr insns (-16).  */
static char *v9a_asr_reg_names[] =
{
  "pcr", "pic", "dcr", "gsr", "set_softint", "clear_softint",
  "softint", "tick_cmpr", "stick", "stick_cmpr", "cfr",
  "pause", "mwait"
};

/* Macros used to extract instruction fields.  Not all fields have
   macros defined here, only those which are actually used.  */

#define X_RD(i)      (((i) >> 25) & 0x1f)
#define X_RS1(i)     (((i) >> 14) & 0x1f)
#define X_LDST_I(i)  (((i) >> 13) & 1)
#define X_ASI(i)     (((i) >> 5) & 0xff)
#define X_RS2(i)     (((i) >> 0) & 0x1f)
#define X_RS3(i)     (((i) >> 9) & 0x1f)
#define X_IMM(i,n)   (((i) >> 0) & ((1 << (n)) - 1))
#define X_SIMM(i,n)  SEX (X_IMM ((i), (n)), (n))
#define X_DISP22(i)  (((i) >> 0) & 0x3fffff)
#define X_IMM22(i)   X_DISP22 (i)
#define X_DISP30(i)  (((i) >> 0) & 0x3fffffff)

/* These are for v9.  */
#define X_DISP16(i)  (((((i) >> 20) & 3) << 14) | (((i) >> 0) & 0x3fff))
#define X_DISP10(i)  (((((i) >> 19) & 3) << 8) | (((i) >> 5) & 0xff))
#define X_DISP19(i)  (((i) >> 0) & 0x7ffff)
#define X_MEMBAR(i)  ((i) & 0x7f)

/* Here is the union which was used to extract instruction fields
   before the shift and mask macros were written.

   union sparc_insn
     {
       unsigned long int code;
       struct
	 {
	   unsigned int anop:2;
	   #define	op	ldst.anop
	   unsigned int anrd:5;
	   #define	rd	ldst.anrd
	   unsigned int op3:6;
	   unsigned int anrs1:5;
	   #define	rs1	ldst.anrs1
	   unsigned int i:1;
	   unsigned int anasi:8;
	   #define	asi	ldst.anasi
	   unsigned int anrs2:5;
	   #define	rs2	ldst.anrs2
	   #define	shcnt	rs2
	 } ldst;
       struct
	 {
	   unsigned int anop:2, anrd:5, op3:6, anrs1:5, i:1;
	   unsigned int IMM13:13;
	   #define	imm13	IMM13.IMM13
	 } IMM13;
       struct
	 {
	   unsigned int anop:2;
	   unsigned int a:1;
	   unsigned int cond:4;
	   unsigned int op2:3;
	   unsigned int DISP22:22;
	   #define	disp22	branch.DISP22
	   #define	imm22	disp22
	 } branch;
       struct
	 {
	   unsigned int anop:2;
	   unsigned int a:1;
	   unsigned int z:1;
	   unsigned int rcond:3;
	   unsigned int op2:3;
	   unsigned int DISP16HI:2;
	   unsigned int p:1;
	   unsigned int _rs1:5;
	   unsigned int DISP16LO:14;
	 } branch16;
       struct
	 {
	   unsigned int anop:2;
	   unsigned int adisp30:30;
	   #define	disp30	call.adisp30
	 } call;
     };  */

/* Nonzero if INSN is the opcode for a delayed branch.  */

static int
is_delayed_branch (unsigned long insn)
{
  sparc_opcode_hash *op;

  for (op = opcode_hash_table[HASH_INSN (insn)]; op; op = op->next)
    {
      const sparc_opcode *opcode = op->opcode;

      if ((opcode->match & insn) == opcode->match
	  && (opcode->lose & insn) == 0)
	return opcode->flags & F_DELAYED;
    }
  return 0;
}

/* extern void qsort (); */

/* Records current mask of SPARC_OPCODE_ARCH_FOO values, used to pass value
   to compare_opcodes.  */
static unsigned int current_arch_mask;

/* Given BFD mach number, return a mask of SPARC_OPCODE_ARCH_FOO values.  */

static int
compute_arch_mask (unsigned long mach)
{
  switch (mach)
    {
    case 0 :
    case bfd_mach_sparc :
      return (SPARC_OPCODE_ARCH_MASK (SPARC_OPCODE_ARCH_V8)
              | SPARC_OPCODE_ARCH_MASK (SPARC_OPCODE_ARCH_LEON));
    case bfd_mach_sparc_sparclet :
      return SPARC_OPCODE_ARCH_MASK (SPARC_OPCODE_ARCH_SPARCLET);
    case bfd_mach_sparc_sparclite :
    case bfd_mach_sparc_sparclite_le :
      /* sparclites insns are recognized by default (because that's how
	 they've always been treated, for better or worse).  Kludge this by
	 indicating generic v8 is also selected.  */
      return (SPARC_OPCODE_ARCH_MASK (SPARC_OPCODE_ARCH_SPARCLITE)
	      | SPARC_OPCODE_ARCH_MASK (SPARC_OPCODE_ARCH_V8));
    case bfd_mach_sparc_v8plus :
    case bfd_mach_sparc_v9 :
      return SPARC_OPCODE_ARCH_MASK (SPARC_OPCODE_ARCH_V9);
    case bfd_mach_sparc_v8plusa :
    case bfd_mach_sparc_v9a :
      return SPARC_OPCODE_ARCH_MASK (SPARC_OPCODE_ARCH_V9A);
    case bfd_mach_sparc_v8plusb :
    case bfd_mach_sparc_v9b :
      return SPARC_OPCODE_ARCH_MASK (SPARC_OPCODE_ARCH_V9B);
    }
  abort ();
}

/* Compare opcodes A and B.  */

static int
compare_opcodes (const void * a, const void * b)
{
  sparc_opcode *op0 = * (sparc_opcode **) a;
  sparc_opcode *op1 = * (sparc_opcode **) b;
  unsigned long int match0 = op0->match, match1 = op1->match;
  unsigned long int lose0 = op0->lose, lose1 = op1->lose;
  register unsigned int i;

  /* If one (and only one) insn isn't supported by the current architecture,
     prefer the one that is.  If neither are supported, but they're both for
     the same architecture, continue processing.  Otherwise (both unsupported
     and for different architectures), prefer lower numbered arch's (fudged
     by comparing the bitmasks).  */
  if (op0->architecture & current_arch_mask)
    {
      if (! (op1->architecture & current_arch_mask))
	return -1;
    }
  else
    {
      if (op1->architecture & current_arch_mask)
	return 1;
      else if (op0->architecture != op1->architecture)
	return op0->architecture - op1->architecture;
    }

  /* If a bit is set in both match and lose, there is something
     wrong with the opcode table.  */
  if (match0 & lose0)
    {
      fprintf
	(stderr,
	 /* xgettext:c-format */
	 _("Internal error:  bad sparc-opcode.h: \"%s\", %#.8lx, %#.8lx\n"),
	 op0->name, match0, lose0);
      op0->lose &= ~op0->match;
      lose0 = op0->lose;
    }

  if (match1 & lose1)
    {
      fprintf
	(stderr,
	 /* xgettext:c-format */
	 _("Internal error: bad sparc-opcode.h: \"%s\", %#.8lx, %#.8lx\n"),
	 op1->name, match1, lose1);
      op1->lose &= ~op1->match;
      lose1 = op1->lose;
    }

  /* Because the bits that are variable in one opcode are constant in
     another, it is important to order the opcodes in the right order.  */
  for (i = 0; i < 32; ++i)
    {
      unsigned long int x = 1 << i;
      int x0 = (match0 & x) != 0;
      int x1 = (match1 & x) != 0;

      if (x0 != x1)
	return x1 - x0;
    }

  for (i = 0; i < 32; ++i)
    {
      unsigned long int x = 1 << i;
      int x0 = (lose0 & x) != 0;
      int x1 = (lose1 & x) != 0;

      if (x0 != x1)
	return x1 - x0;
    }

  /* They are functionally equal.  So as long as the opcode table is
     valid, we can put whichever one first we want, on aesthetic grounds.  */

  /* Our first aesthetic ground is that aliases defer to real insns.  */
  {
    int alias_diff = (op0->flags & F_ALIAS) - (op1->flags & F_ALIAS);

    if (alias_diff != 0)
      /* Put the one that isn't an alias first.  */
      return alias_diff;
  }

  /* Except for aliases, two "identical" instructions had
     better have the same opcode.  This is a sanity check on the table.  */
  i = strcmp (op0->name, op1->name);
  if (i)
    {
      if (op0->flags & F_ALIAS)
	{
	  if (op0->flags & F_PREFERRED)
	    return -1;
	  if (op1->flags & F_PREFERRED)
	    return 1;

	  /* If they're both aliases, and neither is marked as preferred,
	     be arbitrary.  */
	  return i;
	}
      else
	fprintf (stderr,
		 /* xgettext:c-format */
		 _("Internal error: bad sparc-opcode.h: \"%s\" == \"%s\"\n"),
		 op0->name, op1->name);
    }

  /* Fewer arguments are preferred.  */
  {
    int length_diff = strlen (op0->args) - strlen (op1->args);

    if (length_diff != 0)
      /* Put the one with fewer arguments first.  */
      return length_diff;
  }

  /* Put 1+i before i+1.  */
  {
    char *p0 = (char *) strchr (op0->args, '+');
    char *p1 = (char *) strchr (op1->args, '+');

    if (p0 && p1)
      {
	/* There is a plus in both operands.  Note that a plus
	   sign cannot be the first character in args,
	   so the following [-1]'s are valid.  */
	if (p0[-1] == 'i' && p1[1] == 'i')
	  /* op0 is i+1 and op1 is 1+i, so op1 goes first.  */
	  return 1;
	if (p0[1] == 'i' && p1[-1] == 'i')
	  /* op0 is 1+i and op1 is i+1, so op0 goes first.  */
	  return -1;
      }
  }

  /* Put 1,i before i,1.  */
  {
    int i0 = strncmp (op0->args, "i,1", 3) == 0;
    int i1 = strncmp (op1->args, "i,1", 3) == 0;

    if (i0 ^ i1)
      return i0 - i1;
  }

  /* They are, as far as we can tell, identical.
     Since qsort may have rearranged the table partially, there is
     no way to tell which one was first in the opcode table as
     written, so just say there are equal.  */
  /* ??? This is no longer true now that we sort a vector of pointers,
     not the table itself.  */
  return 0;
}

/* Build a hash table from the opcode table.
   OPCODE_TABLE is a sorted list of pointers into the opcode table.  */

static void
build_hash_table (const sparc_opcode **opcode_table,
		  sparc_opcode_hash **hash_table,
		  int num_opcodes)
{
  int i;
  int hash_count[HASH_SIZE];
  static sparc_opcode_hash *hash_buf = NULL;

  /* Start at the end of the table and work backwards so that each
     chain is sorted.  */

  memset (hash_table, 0, HASH_SIZE * sizeof (hash_table[0]));
  memset (hash_count, 0, HASH_SIZE * sizeof (hash_count[0]));
  if (hash_buf != NULL)
    free (hash_buf);
  hash_buf = xmalloc (sizeof (* hash_buf) * num_opcodes);
  for (i = num_opcodes - 1; i >= 0; --i)
    {
      int hash = HASH_INSN (opcode_table[i]->match);
      sparc_opcode_hash *h = &hash_buf[i];

      h->next = hash_table[hash];
      h->opcode = opcode_table[i];
      hash_table[hash] = h;
      ++hash_count[hash];
    }

#if 0 /* for debugging */
  {
    int min_count = num_opcodes, max_count = 0;
    int total;

    for (i = 0; i < HASH_SIZE; ++i)
      {
        if (hash_count[i] < min_count)
	  min_count = hash_count[i];
	if (hash_count[i] > max_count)
	  max_count = hash_count[i];
	total += hash_count[i];
      }

    printf ("Opcode hash table stats: min %d, max %d, ave %f\n",
	    min_count, max_count, (double) total / HASH_SIZE);
  }
#endif
}

/* Print one instruction from MEMADDR on INFO->STREAM.

   We suffix the instruction with a comment that gives the absolute
   address involved, as well as its symbolic form, if the instruction
   is preceded by a findable `sethi' and it either adds an immediate
   displacement to that register, or it is an `add' or `or' instruction
   on that register.  */

int
print_insn_sparc (bfd_vma memaddr, disassemble_info *info)
{
  FILE *stream = info->stream;
  bfd_byte buffer[4];
  unsigned long insn;
  sparc_opcode_hash *op;
  /* Nonzero of opcode table has been initialized.  */
  static int opcodes_initialized = 0;
  /* bfd mach number of last call.  */
  static unsigned long current_mach = 0;
  bfd_vma (*getword) (const void *);

  if (!opcodes_initialized
      || info->mach != current_mach)
    {
      int i;

      current_arch_mask = compute_arch_mask (info->mach);

      if (!opcodes_initialized)
	sorted_opcodes =
	  xmalloc (sparc_num_opcodes * sizeof (sparc_opcode *));
      /* Reset the sorted table so we can resort it.  */
      for (i = 0; i < sparc_num_opcodes; ++i)
	sorted_opcodes[i] = &sparc_opcodes[i];
      qsort ((char *) sorted_opcodes, sparc_num_opcodes,
	     sizeof (sorted_opcodes[0]), compare_opcodes);

      build_hash_table (sorted_opcodes, opcode_hash_table, sparc_num_opcodes);
      current_mach = info->mach;
      opcodes_initialized = 1;
    }

  {
    int status =
      (*info->read_memory_func) (memaddr, buffer, sizeof (buffer), info);

    if (status != 0)
      {
	(*info->memory_error_func) (status, memaddr, info);
	return -1;
      }
  }

  /* On SPARClite variants such as DANlite (sparc86x), instructions
     are always big-endian even when the machine is in little-endian mode.  */
  if (info->endian == BFD_ENDIAN_BIG || info->mach == bfd_mach_sparc_sparclite)
    getword = bfd_getb32;
  else
    getword = bfd_getl32;

  insn = getword (buffer);

  info->insn_info_valid = 1;			/* We do return this info.  */
  info->insn_type = dis_nonbranch;		/* Assume non branch insn.  */
  info->branch_delay_insns = 0;			/* Assume no delay.  */
  info->target = 0;				/* Assume no target known.  */

  for (op = opcode_hash_table[HASH_INSN (insn)]; op; op = op->next)
    {
      const sparc_opcode *opcode = op->opcode;

      /* If the insn isn't supported by the current architecture, skip it.  */
      if (! (opcode->architecture & current_arch_mask))
	continue;

      if ((opcode->match & insn) == opcode->match
	  && (opcode->lose & insn) == 0)
	{
	  /* Nonzero means that we have found an instruction which has
	     the effect of adding or or'ing the imm13 field to rs1.  */
	  int imm_added_to_rs1 = 0;
	  int imm_ored_to_rs1 = 0;

	  /* Nonzero means that we have found a plus sign in the args
	     field of the opcode table.  */
	  int found_plus = 0;

	  /* Nonzero means we have an annulled branch.  */
	  int is_annulled = 0;

	  /* Do we have an `add' or `or' instruction combining an
             immediate with rs1?  */
	  if (opcode->match == 0x80102000) /* or */
	    imm_ored_to_rs1 = 1;
	  if (opcode->match == 0x80002000) /* add */
	    imm_added_to_rs1 = 1;

	  if (X_RS1 (insn) != X_RD (insn)
	      && strchr (opcode->args, 'r') != 0)
	      /* Can't do simple format if source and dest are different.  */
	      continue;
	  if (X_RS2 (insn) != X_RD (insn)
	      && strchr (opcode->args, 'O') != 0)
	      /* Can't do simple format if source and dest are different.  */
	      continue;

	  (*info->fprintf_func) (stream, "%s", opcode->name);

	  {
	    const char *s;

	    if (opcode->args[0] != ',')
	      (*info->fprintf_func) (stream, " ");

	    for (s = opcode->args; *s != '\0'; ++s)
	      {
		while (*s == ',')
		  {
		    (*info->fprintf_func) (stream, ",");
		    ++s;
		    switch (*s)
		      {
		      case 'a':
			(*info->fprintf_func) (stream, "a");
			is_annulled = 1;
			++s;
			continue;
		      case 'N':
			(*info->fprintf_func) (stream, "pn");
			++s;
			continue;

		      case 'T':
			(*info->fprintf_func) (stream, "pt");
			++s;
			continue;

		      default:
			break;
		      }
		  }

		(*info->fprintf_func) (stream, " ");

		switch (*s)
		  {
		  case '+':
		    found_plus = 1;
		    /* Fall through.  */

		  default:
		    (*info->fprintf_func) (stream, "%c", *s);
		    break;

		  case '#':
		    (*info->fprintf_func) (stream, "0");
		    break;

#define	reg(n)	(*info->fprintf_func) (stream, "%%%s", reg_names[n])
		  case '1':
		  case 'r':
		    reg (X_RS1 (insn));
		    break;

		  case '2':
		  case 'O':
		    reg (X_RS2 (insn));
		    break;

		  case 'd':
		    reg (X_RD (insn));
		    break;
#undef	reg

#define	freg(n)		(*info->fprintf_func) (stream, "%%%s", freg_names[n])
#define	fregx(n)	(*info->fprintf_func) (stream, "%%%s", freg_names[((n) & ~1) | (((n) & 1) << 5)])
		  case 'e':
		    freg (X_RS1 (insn));
		    break;
		  case 'v':	/* Double/even.  */
		  case 'V':	/* Quad/multiple of 4.  */
		    fregx (X_RS1 (insn));
		    break;

		  case 'f':
		    freg (X_RS2 (insn));
		    break;
		  case 'B':	/* Double/even.  */
		  case 'R':	/* Quad/multiple of 4.  */
		    fregx (X_RS2 (insn));
		    break;

		  case '4':
		    freg (X_RS3 (insn));
		    break;
		  case '5':	/* Double/even.  */
		    fregx (X_RS3 (insn));
		    break;

		  case 'g':
		    freg (X_RD (insn));
		    break;
		  case 'H':	/* Double/even.  */
		  case 'J':	/* Quad/multiple of 4.  */
		  case '}':     /* Double/even.  */
		    fregx (X_RD (insn));
		    break;
#undef	freg
#undef	fregx

#define	creg(n)	(*info->fprintf_func) (stream, "%%c%u", (unsigned int) (n))
		  case 'b':
		    creg (X_RS1 (insn));
		    break;

		  case 'c':
		    creg (X_RS2 (insn));
		    break;

		  case 'D':
		    creg (X_RD (insn));
		    break;
#undef	creg

		  case 'h':
		    (*info->fprintf_func) (stream, "%%hi(%#x)",
					   ((unsigned) 0xFFFFFFFF
					    & ((int) X_IMM22 (insn) << 10)));
		    break;

		  case 'i':	/* 13 bit immediate.  */
		  case 'I':	/* 11 bit immediate.  */
		  case 'j':	/* 10 bit immediate.  */
		    {
		      int imm;

		      if (*s == 'i')
		        imm = X_SIMM (insn, 13);
		      else if (*s == 'I')
			imm = X_SIMM (insn, 11);
		      else
			imm = X_SIMM (insn, 10);

		      /* Check to see whether we have a 1+i, and take
			 note of that fact.

			 Note: because of the way we sort the table,
			 we will be matching 1+i rather than i+1,
			 so it is OK to assume that i is after +,
			 not before it.  */
		      if (found_plus)
			imm_added_to_rs1 = 1;

		      if (imm <= 9)
			(*info->fprintf_func) (stream, "%d", imm);
		      else
			(*info->fprintf_func) (stream, "%#x", imm);
		    }
		    break;

		  case ')':	/* 5 bit unsigned immediate from RS3.  */
		    (info->fprintf_func) (stream, "%#x", (unsigned int) X_RS3 (insn));
		    break;

		  case 'X':	/* 5 bit unsigned immediate.  */
		  case 'Y':	/* 6 bit unsigned immediate.  */
		    {
		      int imm = X_IMM (insn, *s == 'X' ? 5 : 6);

		      if (imm <= 9)
			(info->fprintf_func) (stream, "%d", imm);
		      else
			(info->fprintf_func) (stream, "%#x", (unsigned) imm);
		    }
		    break;

		  case '3':
		    (info->fprintf_func) (stream, "%ld", X_IMM (insn, 3));
		    break;

		  case 'K':
		    {
		      int mask = X_MEMBAR (insn);
		      int bit = 0x40, printed_one = 0;
		      const char *name;

		      if (mask == 0)
			(info->fprintf_func) (stream, "0");
		      else
			while (bit)
			  {
			    if (mask & bit)
			      {
				if (printed_one)
				  (info->fprintf_func) (stream, "|");
				name = sparc_decode_membar (bit);
				(info->fprintf_func) (stream, "%s", name);
				printed_one = 1;
			      }
			    bit >>= 1;
			  }
		      break;
		    }

		  case '=':
		    info->target = memaddr + SEX (X_DISP10 (insn), 10) * 4;
		    (*info->print_address_func) (info->target, info);
		    break;

		  case 'k':
		    info->target = memaddr + SEX (X_DISP16 (insn), 16) * 4;
		    (*info->print_address_func) (info->target, info);
		    break;

		  case 'G':
		    info->target = memaddr + SEX (X_DISP19 (insn), 19) * 4;
		    (*info->print_address_func) (info->target, info);
		    break;

		  case '6':
		  case '7':
		  case '8':
		  case '9':
		    (*info->fprintf_func) (stream, "%%fcc%c", *s - '6' + '0');
		    break;

		  case 'z':
		    (*info->fprintf_func) (stream, "%%icc");
		    break;

		  case 'Z':
		    (*info->fprintf_func) (stream, "%%xcc");
		    break;

		  case 'E':
		    (*info->fprintf_func) (stream, "%%ccr");
		    break;

		  case 's':
		    (*info->fprintf_func) (stream, "%%fprs");
		    break;

		  case '{':
		    (*info->fprintf_func) (stream, "%%mcdper");
		    break;

		  case 'o':
		    (*info->fprintf_func) (stream, "%%asi");
		    break;

		  case 'W':
		    (*info->fprintf_func) (stream, "%%tick");
		    break;

		  case 'P':
		    (*info->fprintf_func) (stream, "%%pc");
		    break;

		  case '?':
		    if (X_RS1 (insn) == 31)
		      (*info->fprintf_func) (stream, "%%ver");
		    else if ((unsigned) X_RS1 (insn) < 17)
		      (*info->fprintf_func) (stream, "%%%s",
					     v9_priv_reg_names[X_RS1 (insn)]);
		    else
		      (*info->fprintf_func) (stream, "%%reserved");
		    break;

		  case '!':
		    if ((unsigned) X_RD (insn) < 17)
		      (*info->fprintf_func) (stream, "%%%s",
					     v9_priv_reg_names[X_RD (insn)]);
		    else
		      (*info->fprintf_func) (stream, "%%reserved");
		    break;

		  case '$':
		    if ((unsigned) X_RS1 (insn) < 32)
		      (*info->fprintf_func) (stream, "%%%s",
					     v9_hpriv_reg_names[X_RS1 (insn)]);
		    else
		      (*info->fprintf_func) (stream, "%%reserved");
		    break;

		  case '%':
		    if ((unsigned) X_RD (insn) < 32)
		      (*info->fprintf_func) (stream, "%%%s",
					     v9_hpriv_reg_names[X_RD (insn)]);
		    else
		      (*info->fprintf_func) (stream, "%%reserved");
		    break;

		  case '/':
		    if (X_RS1 (insn) < 16 || X_RS1 (insn) > 28)
		      (*info->fprintf_func) (stream, "%%reserved");
		    else
		      (*info->fprintf_func) (stream, "%%%s",
					     v9a_asr_reg_names[X_RS1 (insn)-16]);
		    break;

		  case '_':
		    if (X_RD (insn) < 16 || X_RD (insn) > 28)
		      (*info->fprintf_func) (stream, "%%reserved");
		    else
		      (*info->fprintf_func) (stream, "%%%s",
					     v9a_asr_reg_names[X_RD (insn)-16]);
		    break;

		  case '*':
		    {
		      const char *name = sparc_decode_prefetch (X_RD (insn));

		      if (name)
			(*info->fprintf_func) (stream, "%s", name);
		      else
			(*info->fprintf_func) (stream, "%ld", X_RD (insn));
		      break;
		    }

		  case 'M':
		    (*info->fprintf_func) (stream, "%%asr%ld", X_RS1 (insn));
		    break;

		  case 'm':
		    (*info->fprintf_func) (stream, "%%asr%ld", X_RD (insn));
		    break;

		  case 'L':
		    info->target = memaddr + SEX (X_DISP30 (insn), 30) * 4;
		    (*info->print_address_func) (info->target, info);
		    break;

		  case 'n':
		    (*info->fprintf_func)
		      (stream, "%#x", SEX (X_DISP22 (insn), 22));
		    break;

		  case 'l':
		    info->target = memaddr + SEX (X_DISP22 (insn), 22) * 4;
		    (*info->print_address_func) (info->target, info);
		    break;

		  case 'A':
		    {
		      const char *name = sparc_decode_asi (X_ASI (insn));

		      if (name)
			(*info->fprintf_func) (stream, "%s", name);
		      else
			(*info->fprintf_func) (stream, "(%ld)", X_ASI (insn));
		      break;
		    }

		  case 'C':
		    (*info->fprintf_func) (stream, "%%csr");
		    break;

		  case 'F':
		    (*info->fprintf_func) (stream, "%%fsr");
		    break;

		  case '(':
		    (*info->fprintf_func) (stream, "%%efsr");
		    break;

		  case 'p':
		    (*info->fprintf_func) (stream, "%%psr");
		    break;

		  case 'q':
		    (*info->fprintf_func) (stream, "%%fq");
		    break;

		  case 'Q':
		    (*info->fprintf_func) (stream, "%%cq");
		    break;

		  case 't':
		    (*info->fprintf_func) (stream, "%%tbr");
		    break;

		  case 'w':
		    (*info->fprintf_func) (stream, "%%wim");
		    break;

		  case 'x':
		    (*info->fprintf_func) (stream, "%ld",
					   ((X_LDST_I (insn) << 8)
					    + X_ASI (insn)));
		    break;

		  case 'y':
		    (*info->fprintf_func) (stream, "%%y");
		    break;

		  case 'u':
		  case 'U':
		    {
		      int val = *s == 'U' ? X_RS1 (insn) : X_RD (insn);
		      const char *name = sparc_decode_sparclet_cpreg (val);

		      if (name)
			(*info->fprintf_func) (stream, "%s", name);
		      else
			(*info->fprintf_func) (stream, "%%cpreg(%d)", val);
		      break;
		    }
		  }
	      }
	  }

	  /* If we are adding or or'ing something to rs1, then
	     check to see whether the previous instruction was
	     a sethi to the same register as in the sethi.
	     If so, attempt to print the result of the add or
	     or (in this context add and or do the same thing)
	     and its symbolic value.  */
	  if (imm_ored_to_rs1 || imm_added_to_rs1)
	    {
	      unsigned long prev_insn;
	      int errcode;

	      if (memaddr >= 4)
		errcode =
		  (*info->read_memory_func)
		  (memaddr - 4, buffer, sizeof (buffer), info);
	      else
		errcode = 1;

	      prev_insn = getword (buffer);

	      if (errcode == 0)
		{
		  /* If it is a delayed branch, we need to look at the
		     instruction before the delayed branch.  This handles
		     sequences such as:

		     sethi %o1, %hi(_foo), %o1
		     call _printf
		     or %o1, %lo(_foo), %o1  */

		  if (is_delayed_branch (prev_insn))
		    {
		      if (memaddr >= 8)
			errcode = (*info->read_memory_func)
			  (memaddr - 8, buffer, sizeof (buffer), info);
		      else
			errcode = 1;

		      prev_insn = getword (buffer);
		    }
		}

	      /* If there was a problem reading memory, then assume
		 the previous instruction was not sethi.  */
	      if (errcode == 0)
		{
		  /* Is it sethi to the same register?  */
		  if ((prev_insn & 0xc1c00000) == 0x01000000
		      && X_RD (prev_insn) == X_RS1 (insn))
		    {
		      (*info->fprintf_func) (stream, "\t! ");
		      info->target =
			((unsigned) 0xFFFFFFFF
			 & ((int) X_IMM22 (prev_insn) << 10));
		      if (imm_added_to_rs1)
			info->target += X_SIMM (insn, 13);
		      else
			info->target |= X_SIMM (insn, 13);
		      (*info->print_address_func) (info->target, info);
		      info->insn_type = dis_dref;
		      info->data_size = 4;  /* FIXME!!! */
		    }
		}
	    }

	  if (opcode->flags & (F_UNBR|F_CONDBR|F_JSR))
	    {
	      /* FIXME -- check is_annulled flag.  */
	      (void) is_annulled;
	      if (opcode->flags & F_UNBR)
		info->insn_type = dis_branch;
	      if (opcode->flags & F_CONDBR)
		info->insn_type = dis_condbranch;
	      if (opcode->flags & F_JSR)
		info->insn_type = dis_jsr;
	      if (opcode->flags & F_DELAYED)
		info->branch_delay_insns = 1;
	    }

	  return sizeof (buffer);
	}
    }

  info->insn_type = dis_noninsn;	/* Mark as non-valid instruction.  */
  (*info->fprintf_func) (stream, _("unknown"));
  return sizeof (buffer);
}