arm-dis.c revision 61843
1/* Instruction printing code for the ARM
2   Copyright (C) 1994, 95, 96, 97, 98, 99, 2000 Free Software Foundation, Inc.
3   Contributed by Richard Earnshaw (rwe@pegasus.esprit.ec.org)
4   Modification by James G. Smith (jsmith@cygnus.co.uk)
5
6This file is part of libopcodes.
7
8This program is free software; you can redistribute it and/or modify it under
9the terms of the GNU General Public License as published by the Free
10Software Foundation; either version 2 of the License, or (at your option)
11any later version.
12
13This program is distributed in the hope that it will be useful, but WITHOUT
14ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
15FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
16more details.
17
18You should have received a copy of the GNU General Public License
19along with this program; if not, write to the Free Software
20Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
21
22#include "sysdep.h"
23#include "dis-asm.h"
24#define DEFINE_TABLE
25#include "arm-opc.h"
26#include "coff/internal.h"
27#include "libcoff.h"
28#include "opintl.h"
29
30/* FIXME: This shouldn't be done here */
31#include "elf-bfd.h"
32#include "elf/internal.h"
33#include "elf/arm.h"
34
35#ifndef streq
36#define streq(a,b)	(strcmp ((a), (b)) == 0)
37#endif
38
39#ifndef strneq
40#define strneq(a,b,n)	(strncmp ((a), (b), (n)) == 0)
41#endif
42
43#ifndef NUM_ELEM
44#define NUM_ELEM(a)     (sizeof (a) / sizeof (a)[0])
45#endif
46
47static char * arm_conditional[] =
48{"eq", "ne", "cs", "cc", "mi", "pl", "vs", "vc",
49 "hi", "ls", "ge", "lt", "gt", "le", "", "nv"};
50
51typedef struct
52{
53  const char * name;
54  const char * description;
55  const char * reg_names[16];
56}
57arm_regname;
58
59static arm_regname regnames[] =
60{
61  { "raw" , "Select raw register names",
62    { "r0", "r1", "r2", "r3", "r4", "r5", "r6", "r7", "r8", "r9", "r10", "r11", "r12", "r13", "r14", "r15"}},
63  { "std",  "Select register names used in ARM's ISA documentation",
64    { "r0", "r1", "r2", "r3", "r4", "r5", "r6", "r7", "r8", "r9", "r10", "r11", "r12", "sp",  "lr",  "pc" }},
65  { "apcs", "Select register names used in the APCS",
66    { "a1", "a2", "a3", "a4", "v1", "v2", "v3", "v4", "v5", "v6", "sl",  "fp",  "ip",  "sp",  "lr",  "pc" }},
67  { "atpcs", "Select register names used in the ATPCS",
68    { "a1", "a2", "a3", "a4", "v1", "v2", "v3", "v4", "v5", "v6", "v7",  "v8",  "IP",  "SP",  "LR",  "PC" }},
69  { "special-atpcs", "Select special register names used in the ATPCS",
70    { "a1", "a2", "a3", "a4", "v1", "v2", "v3", "WR", "v5", "SB", "SL",  "FP",  "IP",  "SP",  "LR",  "PC" }}
71};
72
73/* Default to standard register name set.  */
74static unsigned int regname_selected = 1;
75
76#define NUM_ARM_REGNAMES  NUM_ELEM (regnames)
77#define arm_regnames      regnames[regname_selected].reg_names
78
79static boolean force_thumb = false;
80
81static char * arm_fp_const[] =
82{"0.0", "1.0", "2.0", "3.0", "4.0", "5.0", "0.5", "10.0"};
83
84static char * arm_shift[] =
85{"lsl", "lsr", "asr", "ror"};
86
87/* Forward declarations.  */
88static void arm_decode_shift PARAMS ((long, fprintf_ftype, void *));
89static int  print_insn_arm   PARAMS ((bfd_vma, struct disassemble_info *, long));
90static int  print_insn_thumb PARAMS ((bfd_vma, struct disassemble_info *, long));
91static void parse_disassembler_options PARAMS ((char *));
92static int  print_insn       PARAMS ((bfd_vma, struct disassemble_info *, boolean));
93int get_arm_regname_num_options (void);
94int set_arm_regname_option (int option);
95int get_arm_regnames (int option, const char **setname,
96		      const char **setdescription,
97		      const char ***register_names);
98
99/* Functions. */
100int
101get_arm_regname_num_options (void)
102{
103  return NUM_ARM_REGNAMES;
104}
105
106int
107set_arm_regname_option (int option)
108{
109  int old = regname_selected;
110  regname_selected = option;
111  return old;
112}
113
114int
115get_arm_regnames (int option, const char **setname,
116		  const char **setdescription,
117                  const char ***register_names)
118{
119  *setname = regnames[option].name;
120  *setdescription = regnames[option].description;
121  *register_names = regnames[option].reg_names;
122  return 16;
123}
124
125static void
126arm_decode_shift (given, func, stream)
127     long given;
128     fprintf_ftype func;
129     void * stream;
130{
131  func (stream, "%s", arm_regnames[given & 0xf]);
132
133  if ((given & 0xff0) != 0)
134    {
135      if ((given & 0x10) == 0)
136	{
137	  int amount = (given & 0xf80) >> 7;
138	  int shift = (given & 0x60) >> 5;
139
140	  if (amount == 0)
141	    {
142	      if (shift == 3)
143		{
144		  func (stream, ", rrx");
145		  return;
146		}
147
148	      amount = 32;
149	    }
150
151	  func (stream, ", %s #%d", arm_shift[shift], amount);
152	}
153      else
154	func (stream, ", %s %s", arm_shift[(given & 0x60) >> 5],
155	      arm_regnames[(given & 0xf00) >> 8]);
156    }
157}
158
159/* Print one instruction from PC on INFO->STREAM.
160   Return the size of the instruction (always 4 on ARM). */
161static int
162print_insn_arm (pc, info, given)
163     bfd_vma                   pc;
164     struct disassemble_info * info;
165     long                      given;
166{
167  struct arm_opcode *  insn;
168  void *               stream = info->stream;
169  fprintf_ftype        func   = info->fprintf_func;
170
171  for (insn = arm_opcodes; insn->assembler; insn++)
172    {
173      if ((given & insn->mask) == insn->value)
174	{
175	  char * c;
176
177	  for (c = insn->assembler; *c; c++)
178	    {
179	      if (*c == '%')
180		{
181		  switch (*++c)
182		    {
183		    case '%':
184		      func (stream, "%%");
185		      break;
186
187		    case 'a':
188		      if (((given & 0x000f0000) == 0x000f0000)
189			  && ((given & 0x02000000) == 0))
190			{
191			  int offset = given & 0xfff;
192
193			  func (stream, "[pc");
194
195			  if (given & 0x01000000)
196			    {
197			      if ((given & 0x00800000) == 0)
198				offset = - offset;
199
200			      /* pre-indexed */
201			      func (stream, ", #%x]", offset);
202
203			      offset += pc + 8;
204
205			      /* Cope with the possibility of write-back
206				 being used.  Probably a very dangerous thing
207				 for the programmer to do, but who are we to
208				 argue ?  */
209			      if (given & 0x00200000)
210				func (stream, "!");
211			    }
212			  else
213			    {
214			      /* Post indexed.  */
215			      func (stream, "], #%x", offset);
216
217			      offset = pc + 8;  /* ie ignore the offset.  */
218			    }
219
220			  func (stream, "\t; ");
221			  info->print_address_func (offset, info);
222			}
223		      else
224			{
225			  func (stream, "[%s",
226				arm_regnames[(given >> 16) & 0xf]);
227			  if ((given & 0x01000000) != 0)
228			    {
229			      if ((given & 0x02000000) == 0)
230				{
231				  int offset = given & 0xfff;
232				  if (offset)
233				    func (stream, ", %s#%d",
234					  (((given & 0x00800000) == 0)
235					   ? "-" : ""), offset);
236				}
237			      else
238				{
239				  func (stream, ", %s",
240					(((given & 0x00800000) == 0)
241					 ? "-" : ""));
242				  arm_decode_shift (given, func, stream);
243				}
244
245			      func (stream, "]%s",
246				    ((given & 0x00200000) != 0) ? "!" : "");
247			    }
248			  else
249			    {
250			      if ((given & 0x02000000) == 0)
251				{
252				  int offset = given & 0xfff;
253				  if (offset)
254				    func (stream, "], %s#%d",
255					  (((given & 0x00800000) == 0)
256					   ? "-" : ""), offset);
257				  else
258				    func (stream, "]");
259				}
260			      else
261				{
262				  func (stream, "], %s",
263					(((given & 0x00800000) == 0)
264					 ? "-" : ""));
265				  arm_decode_shift (given, func, stream);
266				}
267			    }
268			}
269		      break;
270
271		    case 's':
272                      if ((given & 0x004f0000) == 0x004f0000)
273			{
274                          /* PC relative with immediate offset.  */
275			  int offset = ((given & 0xf00) >> 4) | (given & 0xf);
276
277			  if ((given & 0x00800000) == 0)
278			    offset = -offset;
279
280			  func (stream, "[pc, #%x]\t; ", offset);
281
282			  (*info->print_address_func)
283			    (offset + pc + 8, info);
284			}
285		      else
286			{
287			  func (stream, "[%s",
288				arm_regnames[(given >> 16) & 0xf]);
289			  if ((given & 0x01000000) != 0)
290			    {
291                              /* Pre-indexed.  */
292			      if ((given & 0x00400000) == 0x00400000)
293				{
294                                  /* Immediate.  */
295                                  int offset = ((given & 0xf00) >> 4) | (given & 0xf);
296				  if (offset)
297				    func (stream, ", %s#%d",
298					  (((given & 0x00800000) == 0)
299					   ? "-" : ""), offset);
300				}
301			      else
302				{
303                                  /* Register.  */
304				  func (stream, ", %s%s",
305					(((given & 0x00800000) == 0)
306					 ? "-" : ""),
307                                        arm_regnames[given & 0xf]);
308				}
309
310			      func (stream, "]%s",
311				    ((given & 0x00200000) != 0) ? "!" : "");
312			    }
313			  else
314			    {
315                              /* Post-indexed.  */
316			      if ((given & 0x00400000) == 0x00400000)
317				{
318                                  /* Immediate.  */
319                                  int offset = ((given & 0xf00) >> 4) | (given & 0xf);
320				  if (offset)
321				    func (stream, "], %s#%d",
322					  (((given & 0x00800000) == 0)
323					   ? "-" : ""), offset);
324				  else
325				    func (stream, "]");
326				}
327			      else
328				{
329                                  /* Register.  */
330				  func (stream, "], %s%s",
331					(((given & 0x00800000) == 0)
332					 ? "-" : ""),
333                                        arm_regnames[given & 0xf]);
334				}
335			    }
336			}
337		      break;
338
339		    case 'b':
340		      (*info->print_address_func)
341			(BDISP (given) * 4 + pc + 8, info);
342		      break;
343
344		    case 'c':
345		      func (stream, "%s",
346			    arm_conditional [(given >> 28) & 0xf]);
347		      break;
348
349		    case 'm':
350		      {
351			int started = 0;
352			int reg;
353
354			func (stream, "{");
355			for (reg = 0; reg < 16; reg++)
356			  if ((given & (1 << reg)) != 0)
357			    {
358			      if (started)
359				func (stream, ", ");
360			      started = 1;
361			      func (stream, "%s", arm_regnames[reg]);
362			    }
363			func (stream, "}");
364		      }
365		      break;
366
367		    case 'o':
368		      if ((given & 0x02000000) != 0)
369			{
370			  int rotate = (given & 0xf00) >> 7;
371			  int immed = (given & 0xff);
372			  immed = (((immed << (32 - rotate))
373				    | (immed >> rotate)) & 0xffffffff);
374			  func (stream, "#%d\t; 0x%x", immed, immed);
375			}
376		      else
377			arm_decode_shift (given, func, stream);
378		      break;
379
380		    case 'p':
381		      if ((given & 0x0000f000) == 0x0000f000)
382			func (stream, "p");
383		      break;
384
385		    case 't':
386		      if ((given & 0x01200000) == 0x00200000)
387			func (stream, "t");
388		      break;
389
390		    case 'h':
391		      if ((given & 0x00000020) == 0x00000020)
392			func (stream, "h");
393                      else
394                        func (stream, "b");
395		      break;
396
397		    case 'A':
398		      func (stream, "[%s", arm_regnames [(given >> 16) & 0xf]);
399		      if ((given & 0x01000000) != 0)
400			{
401			  int offset = given & 0xff;
402			  if (offset)
403			    func (stream, ", %s#%d]%s",
404				  ((given & 0x00800000) == 0 ? "-" : ""),
405				  offset * 4,
406				  ((given & 0x00200000) != 0 ? "!" : ""));
407			  else
408			    func (stream, "]");
409			}
410		      else
411			{
412			  int offset = given & 0xff;
413			  if (offset)
414			    func (stream, "], %s#%d",
415				  ((given & 0x00800000) == 0 ? "-" : ""),
416				  offset * 4);
417			  else
418			    func (stream, "]");
419			}
420		      break;
421
422		    case 'C':
423		      switch (given & 0x000f0000)
424			{
425			default:
426			  func (stream, "_???");
427			  break;
428			case 0x90000:
429			  func (stream, "_all");
430			  break;
431			case 0x10000:
432			  func (stream, "_c");
433			  break;
434			case 0x20000:
435			  func (stream, "_x");
436			  break;
437			case 0x40000:
438			  func (stream, "_s");
439			  break;
440			case 0x80000:
441			  func (stream, "_f");
442			  break;
443			}
444		      break;
445
446		    case 'F':
447		      switch (given & 0x00408000)
448			{
449			case 0:
450			  func (stream, "4");
451			  break;
452			case 0x8000:
453			  func (stream, "1");
454			  break;
455			case 0x00400000:
456			  func (stream, "2");
457			  break;
458			default:
459			  func (stream, "3");
460			}
461		      break;
462
463		    case 'P':
464		      switch (given & 0x00080080)
465			{
466			case 0:
467			  func (stream, "s");
468			  break;
469			case 0x80:
470			  func (stream, "d");
471			  break;
472			case 0x00080000:
473			  func (stream, "e");
474			  break;
475			default:
476			  func (stream, _("<illegal precision>"));
477			  break;
478			}
479		      break;
480		    case 'Q':
481		      switch (given & 0x00408000)
482			{
483			case 0:
484			  func (stream, "s");
485			  break;
486			case 0x8000:
487			  func (stream, "d");
488			  break;
489			case 0x00400000:
490			  func (stream, "e");
491			  break;
492			default:
493			  func (stream, "p");
494			  break;
495			}
496		      break;
497		    case 'R':
498		      switch (given & 0x60)
499			{
500			case 0:
501			  break;
502			case 0x20:
503			  func (stream, "p");
504			  break;
505			case 0x40:
506			  func (stream, "m");
507			  break;
508			default:
509			  func (stream, "z");
510			  break;
511			}
512		      break;
513
514		    case '0': case '1': case '2': case '3': case '4':
515		    case '5': case '6': case '7': case '8': case '9':
516		      {
517			int bitstart = *c++ - '0';
518			int bitend = 0;
519			while (*c >= '0' && *c <= '9')
520			  bitstart = (bitstart * 10) + *c++ - '0';
521
522			switch (*c)
523			  {
524			  case '-':
525			    c++;
526
527			    while (*c >= '0' && *c <= '9')
528			      bitend = (bitend * 10) + *c++ - '0';
529
530			    if (!bitend)
531			      abort ();
532
533			    switch (*c)
534			      {
535			      case 'r':
536				{
537				  long reg;
538
539				  reg = given >> bitstart;
540				  reg &= (2 << (bitend - bitstart)) - 1;
541
542				  func (stream, "%s", arm_regnames[reg]);
543				}
544				break;
545			      case 'd':
546				{
547				  long reg;
548
549				  reg = given >> bitstart;
550				  reg &= (2 << (bitend - bitstart)) - 1;
551
552				  func (stream, "%d", reg);
553				}
554				break;
555			      case 'x':
556				{
557				  long reg;
558
559				  reg = given >> bitstart;
560				  reg &= (2 << (bitend - bitstart)) - 1;
561
562				  func (stream, "0x%08x", reg);
563
564				  /* Some SWI instructions have special
565				     meanings.  */
566				  if ((given & 0x0fffffff) == 0x0FF00000)
567				    func (stream, "\t; IMB");
568				  else if ((given & 0x0fffffff) == 0x0FF00001)
569				    func (stream, "\t; IMBRange");
570				}
571				break;
572			      case 'X':
573				{
574				  long reg;
575
576				  reg = given >> bitstart;
577				  reg &= (2 << (bitend - bitstart)) - 1;
578
579				  func (stream, "%01x", reg & 0xf);
580				}
581				break;
582			      case 'f':
583				{
584				  long reg;
585
586				  reg = given >> bitstart;
587				  reg &= (2 << (bitend - bitstart)) - 1;
588
589				  if (reg > 7)
590				    func (stream, "#%s",
591					  arm_fp_const[reg & 7]);
592				  else
593				    func (stream, "f%d", reg);
594				}
595				break;
596			      default:
597				abort ();
598			      }
599			    break;
600
601			  case '`':
602			    c++;
603			    if ((given & (1 << bitstart)) == 0)
604			      func (stream, "%c", *c);
605			    break;
606			  case '\'':
607			    c++;
608			    if ((given & (1 << bitstart)) != 0)
609			      func (stream, "%c", *c);
610			    break;
611			  case '?':
612			    ++c;
613			    if ((given & (1 << bitstart)) != 0)
614			      func (stream, "%c", *c++);
615			    else
616			      func (stream, "%c", *++c);
617			    break;
618			  default:
619			    abort ();
620			  }
621			break;
622
623		      default:
624			abort ();
625		      }
626		    }
627		}
628	      else
629		func (stream, "%c", *c);
630	    }
631	  return 4;
632	}
633    }
634  abort ();
635}
636
637/* Print one instruction from PC on INFO->STREAM.
638   Return the size of the instruction. */
639static int
640print_insn_thumb (pc, info, given)
641     bfd_vma                   pc;
642     struct disassemble_info * info;
643     long                      given;
644{
645  struct thumb_opcode * insn;
646  void *                stream = info->stream;
647  fprintf_ftype         func = info->fprintf_func;
648
649  for (insn = thumb_opcodes; insn->assembler; insn++)
650    {
651      if ((given & insn->mask) == insn->value)
652        {
653          char * c = insn->assembler;
654
655          /* Special processing for Thumb 2 instruction BL sequence:  */
656          if (!*c) /* Check for empty (not NULL) assembler string.  */
657            {
658	      info->bytes_per_chunk = 4;
659	      info->bytes_per_line  = 4;
660
661                func (stream, "bl\t");
662
663              info->print_address_func (BDISP23 (given) * 2 + pc + 4, info);
664              return 4;
665            }
666          else
667            {
668	      info->bytes_per_chunk = 2;
669	      info->bytes_per_line  = 4;
670
671              given &= 0xffff;
672
673              for (; *c; c++)
674                {
675                  if (*c == '%')
676                    {
677                      int domaskpc = 0;
678                      int domasklr = 0;
679
680                      switch (*++c)
681                        {
682                        case '%':
683                          func (stream, "%%");
684                          break;
685
686                        case 'S':
687                          {
688                            long reg;
689
690                            reg = (given >> 3) & 0x7;
691                            if (given & (1 << 6))
692                              reg += 8;
693
694                            func (stream, "%s", arm_regnames[reg]);
695                          }
696                          break;
697
698                        case 'D':
699                          {
700                            long reg;
701
702                            reg = given & 0x7;
703                            if (given & (1 << 7))
704                             reg += 8;
705
706                            func (stream, "%s", arm_regnames[reg]);
707                          }
708                          break;
709
710                        case 'T':
711                          func (stream, "%s",
712                                arm_conditional [(given >> 8) & 0xf]);
713                          break;
714
715                        case 'N':
716                          if (given & (1 << 8))
717                            domasklr = 1;
718                          /* Fall through.  */
719                        case 'O':
720                          if (*c == 'O' && (given & (1 << 8)))
721                            domaskpc = 1;
722                          /* Fall through.  */
723                        case 'M':
724                          {
725                            int started = 0;
726                            int reg;
727
728                            func (stream, "{");
729
730                            /* It would be nice if we could spot
731                               ranges, and generate the rS-rE format: */
732                            for (reg = 0; (reg < 8); reg++)
733                              if ((given & (1 << reg)) != 0)
734                                {
735                                  if (started)
736                                    func (stream, ", ");
737                                  started = 1;
738                                  func (stream, "%s", arm_regnames[reg]);
739                                }
740
741                            if (domasklr)
742                              {
743                                if (started)
744                                  func (stream, ", ");
745                                started = 1;
746                                func (stream, arm_regnames[14] /* "lr" */);
747                              }
748
749                            if (domaskpc)
750                              {
751                                if (started)
752                                  func (stream, ", ");
753                                func (stream, arm_regnames[15] /* "pc" */);
754                              }
755
756                            func (stream, "}");
757                          }
758                          break;
759
760
761                        case '0': case '1': case '2': case '3': case '4':
762                        case '5': case '6': case '7': case '8': case '9':
763                          {
764                            int bitstart = *c++ - '0';
765                            int bitend = 0;
766
767                            while (*c >= '0' && *c <= '9')
768                              bitstart = (bitstart * 10) + *c++ - '0';
769
770                            switch (*c)
771                              {
772                              case '-':
773                                {
774                                  long reg;
775
776                                  c++;
777                                  while (*c >= '0' && *c <= '9')
778                                    bitend = (bitend * 10) + *c++ - '0';
779                                  if (!bitend)
780                                    abort ();
781                                  reg = given >> bitstart;
782                                  reg &= (2 << (bitend - bitstart)) - 1;
783                                  switch (*c)
784                                    {
785                                    case 'r':
786                                      func (stream, "%s", arm_regnames[reg]);
787                                      break;
788
789                                    case 'd':
790                                      func (stream, "%d", reg);
791                                      break;
792
793                                    case 'H':
794                                      func (stream, "%d", reg << 1);
795                                      break;
796
797                                    case 'W':
798                                      func (stream, "%d", reg << 2);
799                                      break;
800
801                                    case 'a':
802				      /* PC-relative address -- the bottom two
803					 bits of the address are dropped
804					 before the calculation.  */
805                                      info->print_address_func
806					(((pc + 4) & ~3) + (reg << 2), info);
807                                      break;
808
809                                    case 'x':
810                                      func (stream, "0x%04x", reg);
811                                      break;
812
813                                    case 'I':
814                                      reg = ((reg ^ (1 << bitend)) - (1 << bitend));
815                                      func (stream, "%d", reg);
816                                      break;
817
818                                    case 'B':
819                                      reg = ((reg ^ (1 << bitend)) - (1 << bitend));
820                                      (*info->print_address_func)
821                                        (reg * 2 + pc + 4, info);
822                                      break;
823
824                                    default:
825                                      abort ();
826                                    }
827                                }
828                                break;
829
830                              case '\'':
831                                c++;
832                                if ((given & (1 << bitstart)) != 0)
833                                  func (stream, "%c", *c);
834                                break;
835
836                              case '?':
837                                ++c;
838                                if ((given & (1 << bitstart)) != 0)
839                                  func (stream, "%c", *c++);
840                                else
841                                  func (stream, "%c", *++c);
842                                break;
843
844                              default:
845                                 abort ();
846                              }
847                          }
848                          break;
849
850                        default:
851                          abort ();
852                        }
853                    }
854                  else
855                    func (stream, "%c", *c);
856                }
857             }
858          return 2;
859       }
860    }
861
862  /* No match.  */
863  abort ();
864}
865
866/* Parse an individual disassembler option.  */
867void
868parse_arm_disassembler_option (option)
869     char * option;
870{
871  if (option == NULL)
872    return;
873
874  if (strneq (option, "reg-names-", 10))
875    {
876      int i;
877
878      option += 10;
879
880      for (i = NUM_ARM_REGNAMES; i--;)
881	if (streq (option, regnames[i].name))
882	  {
883	    regname_selected = i;
884	    break;
885	  }
886
887      if (i < 0)
888	fprintf (stderr, _("Unrecognised register name set: %s\n"), option);
889    }
890  else if (streq (option, "force-thumb"))
891    force_thumb = 1;
892  else if (streq (option, "no-force-thumb"))
893    force_thumb = 0;
894  else
895    fprintf (stderr, _("Unrecognised disassembler option: %s\n"), option);
896
897  return;
898}
899
900/* Parse the string of disassembler options, spliting it at whitespaces.  */
901static void
902parse_disassembler_options (options)
903     char * options;
904{
905  char * space;
906
907  if (options == NULL)
908    return;
909
910  do
911    {
912      space = strchr (options, ' ');
913
914      if (space)
915	{
916	  * space = '\0';
917	  parse_arm_disassembler_option (options);
918	  * space = ' ';
919	  options = space + 1;
920	}
921      else
922	parse_arm_disassembler_option (options);
923    }
924  while (space);
925}
926
927/* NOTE: There are no checks in these routines that
928   the relevant number of data bytes exist.  */
929static int
930print_insn (pc, info, little)
931     bfd_vma pc;
932     struct disassemble_info * info;
933     boolean little;
934{
935  unsigned char      b[4];
936  long               given;
937  int                status;
938  int                is_thumb;
939
940  if (info->disassembler_options)
941    {
942      parse_disassembler_options (info->disassembler_options);
943
944      /* To avoid repeated parsing of these options, we remove them here.  */
945      info->disassembler_options = NULL;
946    }
947
948  is_thumb = force_thumb;
949
950  if (!is_thumb && info->symbols != NULL)
951    {
952      if (bfd_asymbol_flavour (*info->symbols) == bfd_target_coff_flavour)
953	{
954	  coff_symbol_type * cs;
955
956	  cs = coffsymbol (*info->symbols);
957	  is_thumb = (   cs->native->u.syment.n_sclass == C_THUMBEXT
958		      || cs->native->u.syment.n_sclass == C_THUMBSTAT
959		      || cs->native->u.syment.n_sclass == C_THUMBLABEL
960		      || cs->native->u.syment.n_sclass == C_THUMBEXTFUNC
961		      || cs->native->u.syment.n_sclass == C_THUMBSTATFUNC);
962	}
963      else if (bfd_asymbol_flavour (*info->symbols) == bfd_target_elf_flavour)
964	{
965	  elf_symbol_type *  es;
966	  unsigned int       type;
967
968	  es = *(elf_symbol_type **)(info->symbols);
969	  type = ELF_ST_TYPE (es->internal_elf_sym.st_info);
970
971	  is_thumb = (type == STT_ARM_TFUNC) || (type == STT_ARM_16BIT);
972	}
973    }
974
975  info->bytes_per_chunk = 4;
976  info->display_endian  = little ? BFD_ENDIAN_LITTLE : BFD_ENDIAN_BIG;
977
978  if (little)
979    {
980      status = info->read_memory_func (pc, (bfd_byte *) &b[0], 4, info);
981      if (status != 0 && is_thumb)
982	{
983	  info->bytes_per_chunk = 2;
984
985	  status = info->read_memory_func (pc, (bfd_byte *) b, 2, info);
986	  b[3] = b[2] = 0;
987	}
988
989      if (status != 0)
990	{
991	  info->memory_error_func (status, pc, info);
992	  return -1;
993	}
994
995      given = (b[0]) | (b[1] << 8) | (b[2] << 16) | (b[3] << 24);
996    }
997  else
998    {
999      status = info->read_memory_func
1000	(pc & ~ 0x3, (bfd_byte *) &b[0], 4, info);
1001      if (status != 0)
1002	{
1003	  info->memory_error_func (status, pc, info);
1004	  return -1;
1005	}
1006
1007      if (is_thumb)
1008	{
1009	  if (pc & 0x2)
1010	    {
1011	      given = (b[2] << 8) | b[3];
1012
1013	      status = info->read_memory_func
1014		((pc + 4) & ~ 0x3, (bfd_byte *) b, 4, info);
1015	      if (status != 0)
1016		{
1017		  info->memory_error_func (status, pc + 4, info);
1018		  return -1;
1019		}
1020
1021	      given |= (b[0] << 24) | (b[1] << 16);
1022	    }
1023	  else
1024	    given = (b[0] << 8) | b[1] | (b[2] << 24) | (b[3] << 16);
1025	}
1026      else
1027	given = (b[0] << 24) | (b[1] << 16) | (b[2] << 8) | (b[3]);
1028    }
1029
1030  if (is_thumb)
1031    status = print_insn_thumb (pc, info, given);
1032  else
1033    status = print_insn_arm (pc, info, given);
1034
1035  return status;
1036}
1037
1038int
1039print_insn_big_arm (pc, info)
1040     bfd_vma pc;
1041     struct disassemble_info * info;
1042{
1043  return print_insn (pc, info, false);
1044}
1045
1046int
1047print_insn_little_arm (pc, info)
1048     bfd_vma pc;
1049     struct disassemble_info * info;
1050{
1051  return print_insn (pc, info, true);
1052}
1053
1054void
1055print_arm_disassembler_options (FILE * stream)
1056{
1057  int i;
1058
1059  fprintf (stream, _("\n\
1060The following ARM specific disassembler options are supported for use with\n\
1061the -M switch:\n"));
1062
1063  for (i = NUM_ARM_REGNAMES; i--;)
1064    fprintf (stream, "  reg-names-%s %*c%s\n",
1065	     regnames[i].name,
1066	     14 - strlen (regnames[i].name), ' ',
1067	     regnames[i].description);
1068
1069  fprintf (stream, "  force-thumb              Assume all insns are Thumb insns\n");
1070  fprintf (stream, "  no-force-thumb           Examine preceeding label to determine an insn's type\n\n");
1071}
1072