gdb/vax-pinsn.c

   1 /* Print VAX instructions for GDB, the GNU debugger.
   2    Copyright 1986, 1989, 1991, 1992 Free Software Foundation, Inc.
   3
   4 This file is part of GDB.
   5
   6 This program is free software; you can redistribute it and/or modify
   7 it under the terms of the GNU General Public License as published by
   8 the Free Software Foundation; either version 2 of the License, or
   9 (at your option) any later version.
  10
  11 This program is distributed in the hope that it will be useful,
  12 but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 GNU General Public License for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with this program; if not, write to the Free Software
  18 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.  */
  19
  20 #include "defs.h"
  21 #include "symtab.h"
  22 #include "opcode/vax.h"
  23
  24 /* Vax instructions are never longer than this.  */
  25 #define MAXLEN 62
  26
  27 /* Number of elements in the opcode table.  */
  28 #define NOPCODES (sizeof votstrs / sizeof votstrs[0])
  29
  30 static unsigned char *print_insn_arg ();
  31 \f
  32 /* Print the vax instruction at address MEMADDR in debugged memory,
  33    on STREAM.  Returns length of the instruction, in bytes.  */
  34
  35 int
  36 print_insn (memaddr, stream)
  37      CORE_ADDR memaddr;
  38      FILE *stream;
  39 {
  40   unsigned char buffer[MAXLEN];
  41   register int i;
  42   register unsigned char *p;
  43   register char *d;
  44
  45   read_memory (memaddr, buffer, MAXLEN);
  46
  47   for (i = 0; i < NOPCODES; i++)
  48     if (votstrs[i].detail.code == buffer[0]
  49         || votstrs[i].detail.code == *(unsigned short *)buffer)
  50       break;
  51
  52   /* Handle undefined instructions.  */
  53   if (i == NOPCODES)
  54     {
  55       fprintf (stream, "0%o", buffer[0]);
  56       return 1;
  57     }
  58
  59   fprintf (stream, "%s", votstrs[i].name);
  60
  61   /* Point at first byte of argument data,
  62      and at descriptor for first argument.  */
  63   p = buffer + 1 + (votstrs[i].detail.code >= 0x100);
  64   d = votstrs[i].detail.args;
  65
  66   if (*d)
  67     fputc (' ', stream);
  68
  69   while (*d)
  70     {
  71       p = print_insn_arg (d, p, memaddr + (p - buffer), stream);
  72       d += 2;
  73       if (*d)
  74         fprintf (stream, ",");
  75     }
  76   return p - buffer;
  77 }
  78
  79 static unsigned char *
  80 print_insn_arg (d, p, addr, stream)
  81      char *d;
  82      register char *p;
  83      CORE_ADDR addr;
  84      FILE *stream;
  85 {
  86   register int regnum = *p & 0xf;
  87   float floatlitbuf;
  88
  89   if (*d == 'b')
  90     {
  91       if (d[1] == 'b')
  92         fprintf (stream, "0x%x", addr + *p++ + 1);
  93       else
  94         {
  95           fprintf (stream, "0x%x", addr + *(short *)p + 2);
  96           p += 2;
  97         }
  98     }
  99   else
 100     switch ((*p++ >> 4) & 0xf)
 101       {
 102       case 0:
 103       case 1:
 104       case 2:
 105       case 3:                   /* Literal mode */
 106         if (d[1] == 'd' || d[1] == 'f' || d[1] == 'g' || d[1] == 'h')
 107           {
 108             *(int *)&floatlitbuf = 0x4000 + ((p[-1] & 0x3f) << 4);
 109             fprintf (stream, "$%f", floatlitbuf);
 110           }
 111         else
 112           fprintf (stream, "$%d", p[-1] & 0x3f);
 113         break;
 114
 115       case 4:                   /* Indexed */
 116         p = (char *) print_insn_arg (d, p, addr + 1, stream);
 117         fprintf (stream, "[%s]", reg_names[regnum]);
 118         break;
 119
 120       case 5:                   /* Register */
 121         fprintf (stream, reg_names[regnum]);
 122         break;
 123
 124       case 7:                   /* Autodecrement */
 125         fputc ('-', stream);
 126       case 6:                   /* Register deferred */
 127         fprintf (stream, "(%s)", reg_names[regnum]);
 128         break;
 129
 130       case 9:                   /* Autoincrement deferred */
 131         fputc ('@', stream);
 132         if (regnum == PC_REGNUM)
 133           {
 134             fputc ('#', stream);
 135             print_address (*(long *)p, stream);
 136             p += 4;
 137             break;
 138           }
 139       case 8:                   /* Autoincrement */
 140         if (regnum == PC_REGNUM)
 141           {
 142             fputc ('#', stream);
 143             switch (d[1])
 144               {
 145               case 'b':
 146                 fprintf (stream, "%d", *p++);
 147                 break;
 148
 149               case 'w':
 150                 fprintf (stream, "%d", *(short *)p);
 151                 p += 2;
 152                 break;
 153
 154               case 'l':
 155                 fprintf (stream, "%d", *(long *)p);
 156                 p += 4;
 157                 break;
 158
 159               case 'q':
 160                 fprintf (stream, "0x%x%08x", ((long *)p)[1], ((long *)p)[0]);
 161                 p += 8;
 162                 break;
 163
 164               case 'o':
 165                 fprintf (stream, "0x%x%08x%08x%08x",
 166                          ((long *)p)[3], ((long *)p)[2],
 167                          ((long *)p)[1], ((long *)p)[0]);
 168                 p += 16;
 169                 break;
 170
 171               case 'f':
 172                 if (INVALID_FLOAT (p, 4))
 173                   fprintf (stream, "<<invalid float 0x%x>>", *(int *) p);
 174                 else
 175                   fprintf (stream, "%f", *(float *) p);
 176                 p += 4;
 177                 break;
 178
 179               case 'd':
 180                 if (INVALID_FLOAT (p, 8))
 181                   fprintf (stream, "<<invalid float 0x%x%08x>>",
 182                            ((long *)p)[1], ((long *)p)[0]);
 183                 else
 184                   fprintf (stream, "%f", *(double *) p);
 185                 p += 8;
 186                 break;
 187
 188               case 'g':
 189                 fprintf (stream, "g-float");
 190                 p += 8;
 191                 break;
 192
 193               case 'h':
 194                 fprintf (stream, "h-float");
 195                 p += 16;
 196                 break;
 197
 198               }
 199           }
 200         else
 201           fprintf (stream, "(%s)+", reg_names[regnum]);
 202         break;
 203
 204       case 11:                  /* Byte displacement deferred */
 205         fputc ('@', stream);
 206       case 10:                  /* Byte displacement */
 207         if (regnum == PC_REGNUM)
 208           print_address (addr + *p + 2, stream);
 209         else
 210           fprintf (stream, "%d(%s)", *p, reg_names[regnum]);
 211         p += 1;
 212         break;
 213
 214       case 13:                  /* Word displacement deferred */
 215         fputc ('@', stream);
 216       case 12:                  /* Word displacement */
 217         if (regnum == PC_REGNUM)
 218           print_address (addr + *(short *)p + 3, stream);
 219         else
 220           fprintf (stream, "%d(%s)", *(short *)p, reg_names[regnum]);
 221         p += 2;
 222         break;
 223
 224       case 15:                  /* Long displacement deferred */
 225         fputc ('@', stream);
 226       case 14:                  /* Long displacement */
 227         if (regnum == PC_REGNUM)
 228           print_address (addr + *(long *)p + 5, stream);
 229         else
 230           fprintf (stream, "%d(%s)", *(long *)p, reg_names[regnum]);
 231         p += 4;
 232       }
 233
 234   return (unsigned char *) p;
 235 }