opcodes/i860-dis.c

   1 /* Disassembler for the i860.
   2    Copyright 2000, 2003, 2007 Free Software Foundation, Inc.
   3
   4    Contributed by Jason Eckhardt <jle@cygnus.com>.
   5
   6    This file is part of the GNU opcodes library.
   7
   8    This library is free software; you can redistribute it and/or modify
   9    it under the terms of the GNU General Public License as published by
  10    the Free Software Foundation; either version 3, or (at your option)
  11    any later version.
  12
  13    It is distributed in the hope that it will be useful, but WITHOUT
  14    ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  15    or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public
  16    License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with this program; if not, write to the Free Software
  20    Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
  21    MA 02110-1301, USA.  */
  22
  23 #include "dis-asm.h"
  24 #include "opcode/i860.h"
  25
  26 /* Later we should probably choose the prefix based on which OS flavor.  */
  27 #define I860_REG_PREFIX "%"
  28
  29 /* Integer register names (encoded as 0..31 in the instruction).  */
  30 static const char *const grnames[] =
  31  {"r0",  "r1",  "sp",  "fp",  "r4",  "r5",  "r6",  "r7",
  32   "r8",  "r9",  "r10", "r11", "r12", "r13", "r14", "r15",
  33   "r16", "r17", "r18", "r19", "r20", "r21", "r22", "r23",
  34   "r24", "r25", "r26", "r27", "r28", "r29", "r30", "r31"};
  35
  36 /* FP register names (encoded as 0..31 in the instruction).  */
  37 static const char *const frnames[] =
  38  {"f0",  "f1",  "f2",  "f3",  "f4",  "f5",  "f6",  "f7",
  39   "f8",  "f9",  "f10", "f11", "f12", "f13", "f14", "f15",
  40   "f16", "f17", "f18", "f19", "f20", "f21", "f22", "f23",
  41   "f24", "f25", "f26", "f27", "f28", "f29", "f30", "f31"};
  42
  43 /* Control/status register names (encoded as 0..11 in the instruction).
  44    Registers bear, ccr, p0, p1, p2 and p3 are XP only.  */
  45 static const char *const crnames[] =
  46  {"fir", "psr", "dirbase", "db", "fsr", "epsr", "bear", "ccr",
  47   "p0", "p1", "p2", "p3", "--", "--", "--", "--" };
  48
  49
  50
  51 /* True if opcode is xor, xorh, and, andh, or, orh, andnot, andnoth.  */
  52 #define BITWISE_OP(op)  ((op) == 0x30 || (op) == 0x31           \
  53                          || (op) == 0x34 || (op) == 0x35        \
  54                          || (op) == 0x38 || (op) == 0x39        \
  55                          || (op) == 0x3c || (op) == 0x3d        \
  56                          || (op) == 0x33 || (op) == 0x37        \
  57                          || (op) == 0x3b || (op) == 0x3f)
  58
  59
  60 /* Sign extend N-bit number.  */
  61 static int
  62 sign_ext (unsigned int x, int n)
  63 {
  64   int t;
  65   t = x >> (n - 1);
  66   t = ((-t) << n) | x;
  67   return t;
  68 }
  69
  70
  71 /* Print a PC-relative branch offset.  VAL is the sign extended value
  72    from the branch instruction.  */
  73 static void
  74 print_br_address (disassemble_info *info, bfd_vma memaddr, long val)
  75 {
  76
  77   long adj = (long)memaddr + 4 + (val << 2);
  78
  79   (*info->fprintf_func) (info->stream, "0x%08lx", adj);
  80
  81   /* Attempt to obtain a symbol for the target address.  */
  82
  83   if (info->print_address_func && adj != 0)
  84     {
  85       (*info->fprintf_func) (info->stream, "\t// ");
  86       (*info->print_address_func) (adj, info);
  87     }
  88 }
  89
  90
  91 /* Print one instruction.  */
  92 int
  93 print_insn_i860 (bfd_vma memaddr, disassemble_info *info)
  94 {
  95   bfd_byte buff[4];
  96   unsigned int insn, i;
  97   int status;
  98   const struct i860_opcode *opcode = 0;
  99
 100   status = (*info->read_memory_func) (memaddr, buff, sizeof (buff), info);
 101   if (status != 0)
 102     {
 103       (*info->memory_error_func) (status, memaddr, info);
 104       return -1;
 105     }
 106
 107   /* Note that i860 instructions are always accessed as little endian
 108      data, regardless of the endian mode of the i860.  */
 109   insn = bfd_getl32 (buff);
 110
 111   status = 0;
 112   i = 0;
 113   while (i860_opcodes[i].name != NULL)
 114     {
 115       opcode = &i860_opcodes[i];
 116       if ((insn & opcode->match) == opcode->match
 117           && (insn & opcode->lose) == 0)
 118         {
 119           status = 1;
 120           break;
 121         }
 122       ++i;
 123     }
 124
 125   if (status == 0)
 126     {
 127       /* Instruction not in opcode table.  */
 128       (*info->fprintf_func) (info->stream, ".long %#08x", insn);
 129     }
 130   else
 131     {
 132       const char *s;
 133       int val;
 134
 135       /* If this a flop (or a shrd) and its dual bit is set,
 136          prefix with 'd.'.  */
 137       if (((insn & 0xfc000000) == 0x48000000
 138            || (insn & 0xfc000000) == 0xb0000000)
 139           && (insn & 0x200))
 140         (*info->fprintf_func) (info->stream, "d.%s\t", opcode->name);
 141       else
 142         (*info->fprintf_func) (info->stream, "%s\t", opcode->name);
 143
 144       for (s = opcode->args; *s; s++)
 145         {
 146           switch (*s)
 147             {
 148             /* Integer register (src1).  */
 149             case '1':
 150               (*info->fprintf_func) (info->stream, "%s%s", I860_REG_PREFIX,
 151                                      grnames[(insn >> 11) & 0x1f]);
 152               break;
 153
 154             /* Integer register (src2).  */
 155             case '2':
 156               (*info->fprintf_func) (info->stream, "%s%s", I860_REG_PREFIX,
 157                                      grnames[(insn >> 21) & 0x1f]);
 158               break;
 159
 160             /* Integer destination register.  */
 161             case 'd':
 162               (*info->fprintf_func) (info->stream, "%s%s", I860_REG_PREFIX,
 163                                      grnames[(insn >> 16) & 0x1f]);
 164               break;
 165
 166             /* Floating-point register (src1).  */
 167             case 'e':
 168               (*info->fprintf_func) (info->stream, "%s%s", I860_REG_PREFIX,
 169                                      frnames[(insn >> 11) & 0x1f]);
 170               break;
 171
 172             /* Floating-point register (src2).  */
 173             case 'f':
 174               (*info->fprintf_func) (info->stream, "%s%s", I860_REG_PREFIX,
 175                                      frnames[(insn >> 21) & 0x1f]);
 176               break;
 177
 178             /* Floating-point destination register.  */
 179             case 'g':
 180               (*info->fprintf_func) (info->stream, "%s%s", I860_REG_PREFIX,
 181                                      frnames[(insn >> 16) & 0x1f]);
 182               break;
 183
 184             /* Control register.  */
 185             case 'c':
 186               (*info->fprintf_func) (info->stream, "%s%s", I860_REG_PREFIX,
 187                                      crnames[(insn >> 21) & 0xf]);
 188               break;
 189
 190             /* 16-bit immediate (sign extend, except for bitwise ops).  */
 191             case 'i':
 192               if (BITWISE_OP ((insn & 0xfc000000) >> 26))
 193                 (*info->fprintf_func) (info->stream, "0x%04x",
 194                                        (unsigned int) (insn & 0xffff));
 195               else
 196                 (*info->fprintf_func) (info->stream, "%d",
 197                                        sign_ext ((insn & 0xffff), 16));
 198               break;
 199
 200             /* 16-bit immediate, aligned (2^0, ld.b).  */
 201             case 'I':
 202               (*info->fprintf_func) (info->stream, "%d",
 203                                      sign_ext ((insn & 0xffff), 16));
 204               break;
 205
 206             /* 16-bit immediate, aligned (2^1, ld.s).  */
 207             case 'J':
 208               (*info->fprintf_func) (info->stream, "%d",
 209                                      sign_ext ((insn & 0xfffe), 16));
 210               break;
 211
 212             /* 16-bit immediate, aligned (2^2, ld.l, {p}fld.l, fst.l).  */
 213             case 'K':
 214               (*info->fprintf_func) (info->stream, "%d",
 215                                      sign_ext ((insn & 0xfffc), 16));
 216               break;
 217
 218             /* 16-bit immediate, aligned (2^3, {p}fld.d, fst.d).  */
 219             case 'L':
 220               (*info->fprintf_func) (info->stream, "%d",
 221                                      sign_ext ((insn & 0xfff8), 16));
 222               break;
 223
 224             /* 16-bit immediate, aligned (2^4, {p}fld.q, fst.q).  */
 225             case 'M':
 226               (*info->fprintf_func) (info->stream, "%d",
 227                                      sign_ext ((insn & 0xfff0), 16));
 228               break;
 229
 230             /* 5-bit immediate (zero extend).  */
 231             case '5':
 232               (*info->fprintf_func) (info->stream, "%d",
 233                                      ((insn >> 11) & 0x1f));
 234               break;
 235
 236             /* Split 16 bit immediate (20..16:10..0).  */
 237             case 's':
 238               val = ((insn >> 5) & 0xf800) | (insn & 0x07ff);
 239               (*info->fprintf_func) (info->stream, "%d",
 240                                      sign_ext (val, 16));
 241               break;
 242
 243             /* Split 16 bit immediate, aligned. (2^0, st.b).  */
 244             case 'S':
 245               val = ((insn >> 5) & 0xf800) | (insn & 0x07ff);
 246               (*info->fprintf_func) (info->stream, "%d",
 247                                      sign_ext (val, 16));
 248               break;
 249
 250             /* Split 16 bit immediate, aligned. (2^1, st.s).  */
 251             case 'T':
 252               val = ((insn >> 5) & 0xf800) | (insn & 0x07fe);
 253               (*info->fprintf_func) (info->stream, "%d",
 254                                      sign_ext (val, 16));
 255               break;
 256
 257             /* Split 16 bit immediate, aligned. (2^2, st.l).  */
 258             case 'U':
 259               val = ((insn >> 5) & 0xf800) | (insn & 0x07fc);
 260               (*info->fprintf_func) (info->stream, "%d",
 261                                      sign_ext (val, 16));
 262               break;
 263
 264             /* 26-bit PC relative immediate (lbroff).  */
 265             case 'l':
 266               val = sign_ext ((insn & 0x03ffffff), 26);
 267               print_br_address (info, memaddr, val);
 268               break;
 269
 270             /* 16-bit PC relative immediate (sbroff).  */
 271             case 'r':
 272               val = sign_ext ((((insn >> 5) & 0xf800) | (insn & 0x07ff)), 16);
 273               print_br_address (info, memaddr, val);
 274               break;
 275
 276             default:
 277               (*info->fprintf_func) (info->stream, "%c", *s);
 278               break;
 279             }
 280         }
 281     }
 282
 283   return sizeof (insn);
 284 }
 285