summaryrefslogtreecommitdiffstats
path: root/opcodes/mmix-dis.c
blob: c81e679f4e1164ce6a524ce1518f1c72454e091c (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
/* mmix-dis.c -- Disassemble MMIX instructions.
   Copyright (C) 2000, 2001 Free Software Foundation, Inc.
   Written by Hans-Peter Nilsson (hp@bitrange.com)

This file is part of GDB and the GNU binutils.

GDB and the GNU binutils are free software; you can redistribute
them and/or modify them under the terms of the GNU General Public
License as published by the Free Software Foundation; either version 2,
or (at your option) any later version.

GDB and the GNU binutils are distributed in the hope that they
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 file; see the file COPYING.  If not, write to the Free
Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */

#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include "opcode/mmix.h"
#include "dis-asm.h"
#include "libiberty.h"
#include "bfd.h"
#include "opintl.h"

#define BAD_CASE(x)				\
 do						\
   {						\
     fprintf (stderr,				\
	      _("Bad case %d (%s) in %s:%d\n"),	\
	      x, #x, __FILE__, __LINE__);	\
     abort ();					\
   }						\
 while (0)

#define FATAL_DEBUG								\
 do										\
   {										\
     fprintf (stderr,								\
	      _("Internal: Non-debugged code (test-case missing): %s:%d"),	\
	      __FILE__, __LINE__);						\
     abort ();									\
   }						\
 while (0)

#define ROUND_MODE(n)					\
 ((n) == 1 ? "ROUND_OFF" : (n) == 2 ? "ROUND_UP" :	\
  (n) == 3 ? "ROUND_DOWN" : (n) == 4 ? "ROUND_NEAR" :	\
  _("(unknown)"))

#define INSN_IMMEDIATE_BIT (IMM_OFFSET_BIT << 24)
#define INSN_BACKWARD_OFFSET_BIT (1 << 24)

struct mmix_dis_info
 {
   const char *reg_name[256];
   const char *spec_reg_name[32];

   /* Waste a little memory so we don't have to allocate each separately.
      We could have an array with static contents for these, but on the
      other hand, we don't have to.  */
   char basic_reg_name[256][sizeof ("$255")];
 };

static boolean initialize_mmix_dis_info PARAMS ((struct disassemble_info *));
static const struct mmix_opcode *get_opcode PARAMS ((unsigned long));


/* Initialize a target-specific array in INFO.  */

static boolean
initialize_mmix_dis_info (info)
     struct disassemble_info *info;
{
  struct mmix_dis_info *minfop = malloc (sizeof (struct mmix_dis_info));
  int i;

  if (minfop == NULL)
    return false;

  memset (minfop, 0, sizeof (*minfop));

  /* Initialize register names from register symbols.  If there's no
     register section, then there are no register symbols.  */
  if ((info->section != NULL && info->section->owner != NULL)
      || (info->symbols != NULL
	  && info->symbols[0] != NULL
	  && bfd_asymbol_bfd (info->symbols[0]) != NULL))
    {
      bfd *abfd = info->section && info->section->owner != NULL
	? info->section->owner
	: bfd_asymbol_bfd (info->symbols[0]);
      asection *reg_section = bfd_get_section_by_name (abfd, "*REG*");

      if (reg_section != NULL)
	{
	  /* The returned symcount *does* include the ending NULL.  */
	  long symsize = bfd_get_symtab_upper_bound (abfd);
	  asymbol **syms = malloc (symsize);
	  long nsyms;
	  long i;

	  if (syms == NULL)
	    { FATAL_DEBUG;
	      free (minfop);
	      return false;
	    }
	  nsyms = bfd_canonicalize_symtab (abfd, syms);

	  /* We use the first name for a register.  If this is MMO, then
	     it's the name with the first sequence number, presumably the
	     first in the source.  */
	  for (i = 0; i < nsyms && syms[i] != NULL; i++)
	    {
	      if (syms[i]->section == reg_section
		  && syms[i]->value < 256
		  && minfop->reg_name[syms[i]->value] == NULL)
		minfop->reg_name[syms[i]->value] = syms[i]->name;
	    }
	}
    }

  /* Fill in the rest with the canonical names.  */
  for (i = 0; i < 256; i++)
    if (minfop->reg_name[i] == NULL)
      {
	sprintf (minfop->basic_reg_name[i], "$%d", i);
	minfop->reg_name[i] = minfop->basic_reg_name[i];
      }

  /* We assume it's actually a one-to-one mapping of number-to-name.  */
  for (i = 0; mmix_spec_regs[i].name != NULL; i++)
    minfop->spec_reg_name[mmix_spec_regs[i].number] = mmix_spec_regs[i].name;

  info->private_data = (PTR) minfop;
  return true;
}

/* A table indexed by the first byte is constructed as we disassemble each
   tetrabyte.  The contents is a pointer into mmix_insns reflecting the
   first found entry with matching match-bits and lose-bits.  Further
   entries are considered one after one until the operand constraints
   match or the match-bits and lose-bits do not match.  Normally a
   "further entry" will just show that there was no other match.  */

static const struct mmix_opcode *
get_opcode (insn)
     unsigned long insn;
{
  static const struct mmix_opcode **opcodes = NULL;
  const struct mmix_opcode *opcodep = mmix_opcodes;
  unsigned int opcode_part = (insn >> 24) & 255;
  if (opcodes == NULL)
    opcodes = xcalloc (256, sizeof (struct mmix_opcode *));

  opcodep = opcodes[opcode_part];
  if (opcodep == NULL
      || (opcodep->match & insn) != opcodep->match
      || (opcodep->lose & insn) != 0)
    {
      /* Search through the table.  */
      for (opcodep = mmix_opcodes; opcodep->name != NULL; opcodep++)
	{
	  /* FIXME: Break out this into an initialization function.  */
	  if ((opcodep->match & (opcode_part << 24)) == opcode_part
	      && (opcodep->lose & (opcode_part << 24)) == 0)
	    opcodes[opcode_part] = opcodep;

	  if ((opcodep->match & insn) == opcodep->match
	      && (opcodep->lose & insn) == 0)
	    break;
	}
    }

  if (opcodep->name == NULL)
    return NULL;

  /* Check constraints.  If they don't match, loop through the next opcode
     entries.  */
  do
    {
      switch (opcodep->operands)
	{
	  /* These have no restraint on what can be in the lower three
	     bytes.  */
	case mmix_operands_regs:
	case mmix_operands_reg_yz:
	case mmix_operands_regs_z_opt:
	case mmix_operands_regs_z:
	case mmix_operands_jmp:
	case mmix_operands_pushgo:
	case mmix_operands_pop:
	case mmix_operands_sync:
	case mmix_operands_x_regs_z:
	case mmix_operands_neg:
	case mmix_operands_pushj:
	case mmix_operands_regaddr:
	case mmix_operands_get:
	case mmix_operands_set:
	case mmix_operands_save:
	case mmix_operands_unsave:
	case mmix_operands_xyz_opt:
	  return opcodep;

	  /* For a ROUND_MODE, the middle byte must be 0..4.  */
	case mmix_operands_roundregs_z:
	case mmix_operands_roundregs:
	  {
	    int midbyte = (insn >> 8) & 255;
	    if (midbyte <= 4)
	      return opcodep;
	  }
	break;

	case mmix_operands_put:
	  /* A "PUT".  If it is "immediate", then no restrictions,
	     otherwise we have to make sure the register number is < 32.  */
	  if ((insn & INSN_IMMEDIATE_BIT)
	      || ((insn >> 16) & 255) < 32)
	    return opcodep;
	  break;

	case mmix_operands_resume:
	  /* Middle bytes must be zero.  */
	  if ((insn & 0x00ffff00) == 0)
	    return opcodep;
	  break;

	default:
	  BAD_CASE (opcodep->operands);
	}

      opcodep++;
    }
  while ((opcodep->match & insn) == opcodep->match
	 && (opcodep->lose & insn) == 0);

  /* If we got here, we had no match.  */
  return NULL;
}

/* The main disassembly function.  */

int
print_insn_mmix (memaddr, info)
     bfd_vma memaddr;
     struct disassemble_info *info;
{
  unsigned char buffer[4];
  unsigned long insn;
  unsigned int x, y, z;
  const struct mmix_opcode *opcodep;
  int status = (*info->read_memory_func) (memaddr, buffer, 4, info);
  struct mmix_dis_info *minfop;

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

  /* FIXME: Is -1 suitable?  */
  if (info->private_data == NULL
      && ! initialize_mmix_dis_info (info))
    return -1;

  minfop = (struct mmix_dis_info *) info->private_data;
  x = buffer[1];
  y = buffer[2];
  z = buffer[3];

  insn = bfd_getb32 (buffer);

  opcodep = get_opcode (insn);

  if (opcodep == NULL)
    {
      (*info->fprintf_func) (info->stream, _("*unknown*"));
      return 4;
    }

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

  /* Present bytes in the order they are laid out in memory.  */
  info->display_endian = BFD_ENDIAN_BIG;

  info->insn_info_valid = 1;
  info->bytes_per_chunk = 4;
  info->branch_delay_insns = 0;
  info->target = 0;
  switch (opcodep->type)
    {
    case mmix_type_normal:
    case mmix_type_memaccess_block:
      info->insn_type = dis_nonbranch;
      break;

    case mmix_type_branch:
      info->insn_type = dis_branch;
      break;

    case mmix_type_condbranch:
      info->insn_type = dis_condbranch;
      break;

    case mmix_type_memaccess_octa:
      info->insn_type = dis_dref;
      info->data_size = 8;
      break;

    case mmix_type_memaccess_tetra:
      info->insn_type = dis_dref;
      info->data_size = 4;
      break;

    case mmix_type_memaccess_wyde:
      info->insn_type = dis_dref;
      info->data_size = 2;
      break;

    case mmix_type_memaccess_byte:
      info->insn_type = dis_dref;
      info->data_size = 1;
      break;

    case mmix_type_jsr:
      info->insn_type = dis_jsr;
      break;

    default:
      BAD_CASE(opcodep->type);
    }

  switch (opcodep->operands)
    {
    case mmix_operands_regs:
      /*  All registers: "$X,$Y,$Z".  */
      (*info->fprintf_func) (info->stream, "%s,%s,%s",
			     minfop->reg_name[x],
			     minfop->reg_name[y],
			     minfop->reg_name[z]);
      break;

    case mmix_operands_reg_yz:
      /* Like SETH - "$X,YZ".  */
      (*info->fprintf_func) (info->stream, "%s,0x%x",
			     minfop->reg_name[x], y * 256 + z);
      break;

    case mmix_operands_regs_z_opt:
    case mmix_operands_regs_z:
    case mmix_operands_pushgo:
      /* The regular "$X,$Y,$Z|Z".  */
      if (insn & INSN_IMMEDIATE_BIT)
	(*info->fprintf_func) (info->stream, "%s,%s,%d",
			       minfop->reg_name[x], minfop->reg_name[y], z);
      else
	(*info->fprintf_func) (info->stream, "%s,%s,%s",
			       minfop->reg_name[x],
			       minfop->reg_name[y],
			       minfop->reg_name[z]);
      break;

    case mmix_operands_jmp:
      /* Address; only JMP.  */
      {
	bfd_signed_vma offset = (x * 65536 + y * 256 + z) * 4;

	if (insn & INSN_BACKWARD_OFFSET_BIT)
	  offset -= (256 * 65536) * 4;

	info->target = memaddr + offset;
	(*info->print_address_func) (memaddr + offset, info);
      }
      break;

    case mmix_operands_roundregs_z:
      /* Two registers, like FLOT, possibly with rounding: "$X,$Z|Z"
	 "$X,ROUND_MODE,$Z|Z".  */
      if (y != 0)
	{
	  if (insn & INSN_IMMEDIATE_BIT)
	    (*info->fprintf_func) (info->stream, "%s,%s,%d",
				   minfop->reg_name[x],
				   ROUND_MODE (y), z);
	  else
	    (*info->fprintf_func) (info->stream, "%s,%s,%s",
				   minfop->reg_name[x],
				   ROUND_MODE (y),
				   minfop->reg_name[z]);
	}
      else
	{
	  if (insn & INSN_IMMEDIATE_BIT)
	    (*info->fprintf_func) (info->stream, "%s,%d",
				   minfop->reg_name[x], z);
	  else
	    (*info->fprintf_func) (info->stream, "%s,%s",
				   minfop->reg_name[x],
				   minfop->reg_name[z]);
	}
      break;

    case mmix_operands_pop:
      /* Like POP - "X,YZ".  */
      (*info->fprintf_func) (info->stream, "%d,%d", x, y*256 + z);
      break;

    case mmix_operands_roundregs:
      /* Two registers, possibly with rounding: "$X,$Z" or
	 "$X,ROUND_MODE,$Z".  */
      if (y != 0)
	(*info->fprintf_func) (info->stream, "%s,%s,%s",
			       minfop->reg_name[x],
			       ROUND_MODE (y),
			       minfop->reg_name[z]);
      else
	(*info->fprintf_func) (info->stream, "%s,%s",
			       minfop->reg_name[x],
			       minfop->reg_name[z]);
      break;

    case mmix_operands_sync:
	/* Like SYNC - "XYZ".  */
      (*info->fprintf_func) (info->stream, "%u",
			     x * 65536 + y * 256 + z);
      break;

    case mmix_operands_x_regs_z:
      /* Like SYNCD - "X,$Y,$Z|Z".  */
      if (insn & INSN_IMMEDIATE_BIT)
	(*info->fprintf_func) (info->stream, "%d,%s,%d",
			       x, minfop->reg_name[y], z);
      else
	(*info->fprintf_func) (info->stream, "%d,%s,%s",
			       x, minfop->reg_name[y],
			       minfop->reg_name[z]);
      break;

    case mmix_operands_neg:
      /* Like NEG and NEGU - "$X,Y,$Z|Z".  */
      if (insn & INSN_IMMEDIATE_BIT)
	(*info->fprintf_func) (info->stream, "%s,%d,%d",
			       minfop->reg_name[x], y, z);
      else
	(*info->fprintf_func) (info->stream, "%s,%d,%s",
			       minfop->reg_name[x], y,
			       minfop->reg_name[z]);
      break;

    case mmix_operands_pushj:
    case mmix_operands_regaddr:
      /* Like GETA or branches - "$X,Address".  */
      {
	bfd_signed_vma offset = (y * 256 + z) * 4;

	if (insn & INSN_BACKWARD_OFFSET_BIT)
	  offset -= 65536 * 4;

	info->target = memaddr + offset;

	(*info->fprintf_func) (info->stream, "%s,", minfop->reg_name[x]);
	(*info->print_address_func) (memaddr + offset, info);
      }
      break;

    case mmix_operands_get:
      /* GET - "X,spec_reg".  */
      (*info->fprintf_func) (info->stream, "%s,%s",
			     minfop->reg_name[x],
			     minfop->spec_reg_name[z]);
      break;

    case mmix_operands_put:
      /* PUT - "spec_reg,$Z|Z".  */
      if (insn & INSN_IMMEDIATE_BIT)
	(*info->fprintf_func) (info->stream, "%s,%d",
			       minfop->spec_reg_name[x], z);
      else
	(*info->fprintf_func) (info->stream, "%s,%s",
			       minfop->spec_reg_name[x],
			       minfop->reg_name[z]);
      break;

    case mmix_operands_set:
      /*  Two registers, "$X,$Y".  */
      (*info->fprintf_func) (info->stream, "%s,%s",
			     minfop->reg_name[x],
			     minfop->reg_name[y]);
      break;

    case mmix_operands_save:
      /* SAVE - "$X,0".  */
      (*info->fprintf_func) (info->stream, "%s,0", minfop->reg_name[x]);
      break;

    case mmix_operands_unsave:
      /* UNSAVE - "0,$Z".  */
      (*info->fprintf_func) (info->stream, "0,%s", minfop->reg_name[z]);
      break;

    case mmix_operands_xyz_opt:
      /* Like SWYM or TRAP - "X,Y,Z".  */
      (*info->fprintf_func) (info->stream, "%d,%d,%d", x, y, z);
      break;

    case mmix_operands_resume:
      /* Just "Z", like RESUME.  */
      (*info->fprintf_func) (info->stream, "%d", z);
      break;

    default:
      (*info->fprintf_func) (info->stream, _("*unknown operands type: %d*"),
			     opcodep->operands);
      break;
    }

  return 4;
}
OpenPOWER on IntegriCloud