opcodes/mips-dis.c

   1 /* Print mips instructions for GDB, the GNU debugger, or for objdump.
   2    Copyright 1989, 1991, 1992 Free Software Foundation, Inc.
   3    Contributed by Nobuyuki Hikichi(hikichi@sra.co.jp).
   4
   5 This file is part of GDB.
   6
   7 This program is free software; you can redistribute it and/or modify
   8 it under the terms of the GNU General Public License as published by
   9 the Free Software Foundation; either version 2 of the License, or
  10 (at your option) any later version.
  11
  12 This program is distributed in the hope that it will be useful,
  13 but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 GNU General Public License for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with this program; if not, write to the Free Software
  19 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.  */
  20
  21 #include <ansidecl.h>
  22 #include "sysdep.h"
  23 #include "dis-asm.h"
  24 #include "opcode/mips.h"
  25
  26 /* FIXME: we need direct access to the swapping functions.  */
  27 #include "libbfd.h"
  28
  29 /* Mips instructions are never longer than this many bytes.  */
  30 #define MAXLEN 4
  31 \f
  32 /* FIXME: This should be shared with gdb somehow.  */
  33 #define REGISTER_NAMES  \
  34     {   "zero", "at",   "v0",   "v1",   "a0",   "a1",   "a2",   "a3", \
  35         "t0",   "t1",   "t2",   "t3",   "t4",   "t5",   "t6",   "t7", \
  36         "s0",   "s1",   "s2",   "s3",   "s4",   "s5",   "s6",   "s7", \
  37         "t8",   "t9",   "k0",   "k1",   "gp",   "sp",   "s8",   "ra", \
  38         "sr",   "lo",   "hi",   "bad",  "cause","pc",    \
  39         "f0",   "f1",   "f2",   "f3",   "f4",   "f5",   "f6",   "f7", \
  40         "f8",   "f9",   "f10",  "f11",  "f12",  "f13",  "f14",  "f15", \
  41         "f16",  "f17",  "f18",  "f19",  "f20",  "f21",  "f22",  "f23",\
  42         "f24",  "f25",  "f26",  "f27",  "f28",  "f29",  "f30",  "f31",\
  43         "fsr",  "fir",  "fp",   "inx",  "rand", "tlblo","ctxt", "tlbhi",\
  44         "epc",  "prid"\
  45     }
  46
  47 static CONST char * CONST reg_names[] = REGISTER_NAMES;
  48 \f
  49 /* subroutine */
  50 static void
  51 print_insn_arg (d, l, pc, info)
  52      const char *d;
  53      register unsigned long int l;
  54      bfd_vma pc;
  55      struct disassemble_info *info;
  56 {
  57   int delta;
  58
  59   switch (*d)
  60     {
  61     case ',':
  62     case '(':
  63     case ')':
  64       (*info->fprintf_func) (info->stream, "%c", *d);
  65       break;
  66
  67     case 's':
  68     case 'b':
  69     case 'r':
  70     case 'v':
  71       (*info->fprintf_func) (info->stream, "$%s",
  72                              reg_names[(l >> OP_SH_RS) & OP_MASK_RS]);
  73       break;
  74
  75     case 't':
  76     case 'w':
  77       (*info->fprintf_func) (info->stream, "$%s",
  78                              reg_names[(l >> OP_SH_RT) & OP_MASK_RT]);
  79       break;
  80
  81     case 'i':
  82     case 'u':
  83       (*info->fprintf_func) (info->stream, "%d",
  84                         (l >> OP_SH_IMMEDIATE) & OP_MASK_IMMEDIATE);
  85       break;
  86
  87     case 'j': /* same as i, but sign-extended */
  88     case 'o':
  89       delta = (l >> OP_SH_DELTA) & OP_MASK_DELTA;
  90       if (delta & 0x8000)
  91         delta |= ~0xffff;
  92       (*info->fprintf_func) (info->stream, "%d",
  93                              delta);
  94       break;
  95
  96     case 'a':
  97       (*info->print_address_func)
  98         (((pc & 0xF0000000) | (((l >> OP_SH_TARGET) & OP_MASK_TARGET) << 2)),
  99          info);
 100       break;
 101
 102     case 'p':
 103       /* sign extend the displacement */
 104       delta = (l >> OP_SH_DELTA) & OP_MASK_DELTA;
 105       if (delta & 0x8000)
 106         delta |= ~0xffff;
 107       (*info->print_address_func)
 108         ((delta << 2) + pc + 4,
 109          info);
 110       break;
 111
 112     case 'd':
 113       (*info->fprintf_func) (info->stream, "$%s",
 114                              reg_names[(l >> OP_SH_RD) & OP_MASK_RD]);
 115       break;
 116
 117     case 'z':
 118       (*info->fprintf_func) (info->stream, "$%s", reg_names[0]);
 119       break;
 120
 121     case '<':
 122       (*info->fprintf_func) (info->stream, "0x%x",
 123                              (l >> OP_SH_SHAMT) & OP_MASK_SHAMT);
 124       break;
 125
 126     case 'c':
 127       (*info->fprintf_func) (info->stream, "0x%x",
 128                              (l >> OP_SH_CODE) & OP_MASK_CODE);
 129       break;
 130
 131     case 'C':
 132       (*info->fprintf_func) (info->stream, "0x%x",
 133                              (l >> OP_SH_COPZ) & OP_MASK_COPZ);
 134       break;
 135
 136     case 'B':
 137       (*info->fprintf_func) (info->stream, "0x%x",
 138                              (l >> OP_SH_SYSCALL) & OP_MASK_SYSCALL);
 139       break;
 140
 141     case 'S':
 142     case 'V':
 143       (*info->fprintf_func) (info->stream, "$f%d",
 144                              (l >> OP_SH_FS) & OP_MASK_FS);
 145       break;
 146
 147     case 'T':
 148     case 'W':
 149       (*info->fprintf_func) (info->stream, "$f%d",
 150                              (l >> OP_SH_FT) & OP_MASK_FT);
 151       break;
 152
 153     case 'D':
 154       (*info->fprintf_func) (info->stream, "$f%d",
 155                              (l >> OP_SH_FD) & OP_MASK_FD);
 156       break;
 157
 158     case 'E':
 159       (*info->fprintf_func) (info->stream, "$%d",
 160                              (l >> OP_SH_RT) & OP_MASK_RT);
 161       break;
 162
 163     case 'G':
 164       (*info->fprintf_func) (info->stream, "$%d",
 165                              (l >> OP_SH_RD) & OP_MASK_RD);
 166       break;
 167
 168     default:
 169       (*info->fprintf_func) (info->stream,
 170                              "# internal error, undefined modifier(%c)", *d);
 171       break;
 172     }
 173 }
 174 \f
 175 /* Print the mips instruction at address MEMADDR in debugged memory,
 176    on using INFO.  Returns length of the instruction, in bytes, which is
 177    always 4.  BIGENDIAN must be 1 if this is big-endian code, 0 if
 178    this is little-endian code.  */
 179
 180 int
 181 _print_insn_mips (memaddr, word, info)
 182      bfd_vma memaddr;
 183      struct disassemble_info *info;
 184      unsigned long int word;
 185 {
 186   register int i;
 187   register const char *d;
 188
 189   for (i = 0; i < NUMOPCODES; i++)
 190     {
 191       if (mips_opcodes[i].pinfo != INSN_MACRO)
 192         {
 193           register unsigned int match = mips_opcodes[i].match;
 194           register unsigned int mask = mips_opcodes[i].mask;
 195           if ((word & mask) == match)
 196             break;
 197         }
 198     }
 199
 200   /* Handle undefined instructions.  */
 201   if (i == NUMOPCODES)
 202     {
 203       (*info->fprintf_func) (info->stream, "0x%x", word);
 204       return 4;
 205     }
 206
 207   (*info->fprintf_func) (info->stream, "%s", mips_opcodes[i].name);
 208
 209   if (!(d = mips_opcodes[i].args))
 210     return 4;
 211
 212   (*info->fprintf_func) (info->stream, " ");
 213
 214   while (*d)
 215     print_insn_arg (d++, word, memaddr, info);
 216
 217   return 4;
 218 }
 219
 220 int
 221 print_insn_big_mips (memaddr, info)
 222      bfd_vma memaddr;
 223      struct disassemble_info *info;
 224 {
 225   bfd_byte buffer[4];
 226   int status = (*info->read_memory_func) (memaddr, buffer, 4, info);
 227   if (status == 0)
 228     return _print_insn_mips (memaddr, _do_getb32 (buffer), info);
 229   else
 230     {
 231       (*info->memory_error_func) (status, memaddr, info);
 232       return -1;
 233     }
 234 }
 235
 236 int
 237 print_insn_little_mips (memaddr, info)
 238      bfd_vma memaddr;
 239      struct disassemble_info *info;
 240 {
 241   bfd_byte buffer[4];
 242   int status = (*info->read_memory_func) (memaddr, buffer, 4, info);
 243   if (status == 0)
 244     return _print_insn_mips (memaddr, _do_getl32 (buffer), info);
 245   else
 246     {
 247       (*info->memory_error_func) (status, memaddr, info);
 248       return -1;
 249     }
 250 }