gdb/i386-xdep.c

   1 /* Intel 386 stuff.
   2    Copyright (C) 1988, 1989, 1991 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 <stdio.h>
  21 #include "defs.h"
  22 #include "frame.h"
  23 #include "inferior.h"
  24 #include "language.h"
  25 #include "gdbcore.h"
  26
  27 #ifdef USG
  28 #include <sys/types.h>
  29 #endif
  30
  31 #include <sys/param.h>
  32 #include <sys/dir.h>
  33 #include <signal.h>
  34 #include <sys/user.h>
  35 #include <sys/ioctl.h>
  36 #include <fcntl.h>
  37
  38 #include <sys/file.h>
  39 #include <sys/stat.h>
  40
  41 #include <sys/reg.h>
  42 #include "ieee-float.h"
  43
  44 #include "target.h"
  45
  46 extern struct ext_format ext_format_i387;
  47 \f
  48 /* this table must line up with REGISTER_NAMES in m-i386.h */
  49 /* symbols like 'EAX' come from <sys/reg.h> */
  50 static int regmap[] =
  51 {
  52   EAX, ECX, EDX, EBX,
  53   UESP, EBP, ESI, EDI,
  54   EIP, EFL, CS, SS,
  55   DS, ES, FS, GS,
  56 };
  57
  58 /* blockend is the value of u.u_ar0, and points to the
  59  * place where GS is stored
  60  */
  61
  62 int
  63 i386_register_u_addr (blockend, regnum)
  64      int blockend;
  65      int regnum;
  66 {
  67 #if 0
  68   /* this will be needed if fp registers are reinstated */
  69   /* for now, you can look at them with 'info float'
  70    * sys5 wont let you change them with ptrace anyway
  71    */
  72   if (regnum >= FP0_REGNUM && regnum <= FP7_REGNUM)
  73     {
  74       int ubase, fpstate;
  75       struct user u;
  76       ubase = blockend + 4 * (SS + 1) - KSTKSZ;
  77       fpstate = ubase + ((char *)&u.u_fpstate - (char *)&u);
  78       return (fpstate + 0x1c + 10 * (regnum - FP0_REGNUM));
  79     }
  80   else
  81 #endif
  82     return (blockend + 4 * regmap[regnum]);
  83
  84 }
  85
  86 #if 0
  87 /* mauro@olympus 1991.10.20 -- compiling the following code causes
  88    undefined symbols at link time, specifically: corechan, have_inferior_p */
  89 struct env387
  90 {
  91   unsigned short control;
  92   unsigned short r0;
  93   unsigned short status;
  94   unsigned short r1;
  95   unsigned short tag;
  96   unsigned short r2;
  97   unsigned long eip;
  98   unsigned short code_seg;
  99   unsigned short opcode;
 100   unsigned long operand;
 101   unsigned short operand_seg;
 102   unsigned short r3;
 103   unsigned char regs[8][10];
 104 };
 105
 106 static
 107 print_387_status (status, ep)
 108      unsigned short status;
 109      struct env387 *ep;
 110 {
 111   int i;
 112   int bothstatus;
 113   int top;
 114   int fpreg;
 115   unsigned char *p;
 116
 117   bothstatus = ((status != 0) && (ep->status != 0));
 118   if (status != 0)
 119     {
 120       if (bothstatus)
 121         printf ("u: ");
 122       print_387_status_word (status);
 123     }
 124
 125   if (ep->status != 0)
 126     {
 127       if (bothstatus)
 128         printf ("e: ");
 129       print_387_status_word (ep->status);
 130     }
 131
 132   print_387_control_word (ep->control);
 133   printf ("last exception: ");
 134   printf ("opcode %s; ", local_hex_string(ep->opcode));
 135   printf ("pc %s:", local_hex_string(ep->code_seg));
 136   printf ("%s; ", local_hex_string(ep->eip));
 137   printf ("operand %s", local_hex_string(ep->operand_seg));
 138   printf (":%s\n", local_hex_string(ep->operand));
 139
 140   top = (ep->status >> 11) & 7;
 141
 142   printf ("regno  tag  msb              lsb  value\n");
 143   for (fpreg = 7; fpreg >= 0; fpreg--)
 144     {
 145       double val;
 146
 147       printf ("%s %d: ", fpreg == top ? "=>" : "  ", fpreg);
 148
 149       switch ((ep->tag >> (fpreg * 2)) & 3)
 150         {
 151         case 0: printf ("valid "); break;
 152         case 1: printf ("zero  "); break;
 153         case 2: printf ("trap  "); break;
 154         case 3: printf ("empty "); break;
 155         }
 156       for (i = 9; i >= 0; i--)
 157         printf ("%02x", ep->regs[fpreg][i]);
 158
 159       ieee_extended_to_double (&ext_format_i387, (char *)ep->regs[fpreg],
 160                                &val);
 161       printf ("  %g\n", val);
 162     }
 163   if (ep->r0)
 164     printf ("warning: reserved0 is %s\n", local_hex_string(ep->r0));
 165   if (ep->r1)
 166     printf ("warning: reserved1 is %s\n", local_hex_string(ep->r1));
 167   if (ep->r2)
 168     printf ("warning: reserved2 is %s\n", local_hex_string(ep->r2));
 169   if (ep->r3)
 170     printf ("warning: reserved3 is %s\n", local_hex_string(ep->r3));
 171 }
 172
 173 #ifndef U_FPSTATE
 174 #define U_FPSTATE(u) u.u_fpstate
 175 #endif
 176
 177 i386_float_info ()
 178 {
 179   struct user u; /* just for address computations */
 180   int i;
 181   /* fpstate defined in <sys/user.h> */
 182   struct fpstate *fpstatep;
 183   char buf[sizeof (struct fpstate) + 2 * sizeof (int)];
 184   unsigned int uaddr;
 185   char fpvalid = 0;
 186   unsigned int rounded_addr;
 187   unsigned int rounded_size;
 188   extern int corechan;
 189   int skip;
 190
 191   uaddr = (char *)&u.u_fpvalid - (char *)&u;
 192   if (target_has_execution)
 193     {
 194       unsigned int data;
 195       unsigned int mask;
 196
 197       rounded_addr = uaddr & -sizeof (int);
 198       data = ptrace (3, inferior_pid, rounded_addr, 0);
 199       mask = 0xff << ((uaddr - rounded_addr) * 8);
 200
 201       fpvalid = ((data & mask) != 0);
 202     }
 203 #if 0
 204   else
 205     {
 206       if (lseek (corechan, uaddr, 0) < 0)
 207         perror ("seek on core file");
 208       if (myread (corechan, &fpvalid, 1) < 0)
 209         perror ("read on core file");
 210
 211     }
 212 #endif  /* no core support yet */
 213
 214   if (fpvalid == 0)
 215     {
 216       printf ("no floating point status saved\n");
 217       return;
 218     }
 219
 220   uaddr = (char *)&U_FPSTATE(u) - (char *)&u;
 221   if (target_has_execution)
 222     {
 223       int *ip;
 224
 225       rounded_addr = uaddr & -sizeof (int);
 226       rounded_size = (((uaddr + sizeof (struct fpstate)) - uaddr) +
 227                       sizeof (int) - 1) / sizeof (int);
 228       skip = uaddr - rounded_addr;
 229
 230       ip = (int *)buf;
 231       for (i = 0; i < rounded_size; i++)
 232         {
 233           *ip++ = ptrace (3, inferior_pid, rounded_addr, 0);
 234           rounded_addr += sizeof (int);
 235         }
 236     }
 237 #if 0
 238   else
 239     {
 240       if (lseek (corechan, uaddr, 0) < 0)
 241         perror_with_name ("seek on core file");
 242       if (myread (corechan, buf, sizeof (struct fpstate)) < 0)
 243         perror_with_name ("read from core file");
 244       skip = 0;
 245     }
 246  #endif /* 0 */
 247
 248   fpstatep = (struct fpstate *)(buf + skip);
 249   print_387_status (fpstatep->status, (struct env387 *)fpstatep->state);
 250 }
 251 #endif /* mauro@olympus 1991.10.20 */