gdb/mips-pinsn.c

   1 /* Print mips instructions for GDB, the GNU debugger.
   2    Copyright (C) 1989 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 <stdio.h>
  22
  23 #include "defs.h"
  24 #include "param.h"
  25 #include "symtab.h"
  26 #include "mips-opcode.h"
  27
  28 /* Mips instructions are never longer than this many bytes.  */
  29 #define MAXLEN 4
  30
  31 /* Number of elements in the opcode table.  */
  32 #define NOPCODES (sizeof mips_opcodes / sizeof mips_opcodes[0])
  33
  34 #define MKLONG(p)  *(unsigned long*)p
  35
  36 extern char *reg_names[];
  37
  38 \f
  39 /* subroutine */
  40 static unsigned char *
  41 print_insn_arg (d, l, stream, pc)
  42      char *d;
  43      register unsigned long int *l;
  44      FILE *stream;
  45      CORE_ADDR pc;
  46 {
  47   switch (*d)
  48     {
  49     case ',':
  50     case '(':
  51     case ')':
  52       fputc (*d, stream);
  53       break;
  54
  55     case 's':
  56       fprintf (stream, "$%s", reg_names[((struct op_i_fmt *) l)->rs]);
  57       break;
  58
  59     case 't':
  60       fprintf (stream, "$%s", reg_names[((struct op_i_fmt *) l)->rt]);
  61       break;
  62
  63     case 'i':
  64       fprintf (stream, "%d", ((struct op_i_fmt *) l)->immediate);
  65       break;
  66
  67     case 'j': /* same as i, but sign-extended */
  68       fprintf (stream, "%d", ((struct op_b_fmt *) l)->delta);
  69       break;
  70
  71     case 'a':
  72       print_address ((pc & 0xF0000000) | (((struct op_j_fmt *)l)->target << 2),
  73                      stream);
  74       break;
  75
  76     case 'b':
  77       print_address ((((struct op_b_fmt *) l)->delta << 2) + pc + 4, stream);
  78       break;
  79
  80     case 'd':
  81       fprintf (stream, "%s", reg_names[((struct op_r_fmt *) l)->rd]);
  82       break;
  83
  84     case 'h':
  85       fprintf (stream, "0x%x", ((struct op_r_fmt *) l)->shamt);
  86       break;
  87
  88     case 'S':
  89       fprintf (stream, "$f%d", ((struct fop_r_fmt *) l)->fs);
  90       break;
  91
  92     case 'T':
  93       fprintf (stream, "$f%d", ((struct fop_r_fmt *) l)->ft);
  94       break;
  95
  96     case 'D':
  97       fprintf (stream, "$f%d", ((struct fop_r_fmt *) l)->fd);
  98       break;
  99
 100     default:
 101       fprintf (stream, "# internal error, undefined modifier(%c)", *d);
 102       break;
 103     }
 104 }
 105 \f
 106 /* Print the mips instruction at address MEMADDR in debugged memory,
 107    on STREAM.  Returns length of the instruction, in bytes, which
 108    is always 4.  */
 109
 110 int
 111 print_insn (memaddr, stream)
 112      CORE_ADDR memaddr;
 113      FILE *stream;
 114 {
 115   unsigned char buffer[MAXLEN];
 116   register int i;
 117   register char *d;
 118   unsigned long int l;
 119
 120   read_memory (memaddr, buffer, MAXLEN);
 121
 122   for (i = 0; i < NOPCODES; i++)
 123     {
 124       register unsigned int opcode = mips_opcodes[i].opcode;
 125       register unsigned int match = mips_opcodes[i].match;
 126       if ((*(unsigned int*)buffer & match) == opcode)
 127         break;
 128     }
 129
 130   l = MKLONG (buffer);
 131   /* Handle undefined instructions.  */
 132   if (i == NOPCODES)
 133     {
 134       fprintf (stream, "0x%x",l);
 135       return 4;
 136     }
 137
 138   fprintf (stream, "%s", mips_opcodes[i].name);
 139
 140   if (!(d = mips_opcodes[i].args))
 141     return 4;
 142
 143   fputc (' ', stream);
 144
 145   while (*d)
 146     print_insn_arg (d++, &l, stream, memaddr);
 147
 148   return 4;
 149 }