gdb/i386v-nat.c

   1 /* Intel 386 native support.
   2    Copyright (C) 1988, 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 "frame.h"
  22 #include "inferior.h"
  23 #include "language.h"
  24 #include "gdbcore.h"
  25
  26 #ifdef USG
  27 #include <sys/types.h>
  28 #endif
  29
  30 #include <sys/param.h>
  31 #include <sys/dir.h>
  32 #include <signal.h>
  33 #include <sys/user.h>
  34 #include <sys/ioctl.h>
  35 #include <fcntl.h>
  36
  37 #include <sys/file.h>
  38 #include <sys/stat.h>
  39
  40 #include <sys/reg.h>
  41 #include "ieee-float.h"
  42
  43 #include "target.h"
  44
  45 extern struct ext_format ext_format_i387;
  46 \f
  47 /* this table must line up with REGISTER_NAMES in tm-i386v.h */
  48 /* symbols like 'EAX' come from <sys/reg.h> */
  49 static int regmap[] =
  50 {
  51   EAX, ECX, EDX, EBX,
  52   UESP, EBP, ESI, EDI,
  53   EIP, EFL, CS, SS,
  54   DS, ES, FS, GS,
  55 };
  56
  57 /* blockend is the value of u.u_ar0, and points to the
  58  * place where GS is stored
  59  */
  60
  61 int
  62 i386_register_u_addr (blockend, regnum)
  63      int blockend;
  64      int regnum;
  65 {
  66 #if 0
  67   /* this will be needed if fp registers are reinstated */
  68   /* for now, you can look at them with 'info float'
  69    * sys5 wont let you change them with ptrace anyway
  70    */
  71   if (regnum >= FP0_REGNUM && regnum <= FP7_REGNUM)
  72     {
  73       int ubase, fpstate;
  74       struct user u;
  75       ubase = blockend + 4 * (SS + 1) - KSTKSZ;
  76       fpstate = ubase + ((char *)&u.u_fpstate - (char *)&u);
  77       return (fpstate + 0x1c + 10 * (regnum - FP0_REGNUM));
  78     }
  79   else
  80 #endif
  81     return (blockend + 4 * regmap[regnum]);
  82
  83 }
  84
  85 #if 0
  86 /* using FLOAT_INFO as is would be a problem.  FLOAT_INFO is called
  87    via a command xxx and eventually calls ptrace without ever having
  88    traversed the target vector.  This would be terribly impolite
  89    behaviour for a sun4 hosted remote gdb.
  90
  91    A fix might be to move this code into the "info registers" command.
  92    rich@cygnus.com 15 Sept 92. */
  93 i386_float_info ()
  94 {
  95   struct user u; /* just for address computations */
  96   int i;
  97   /* fpstate defined in <sys/user.h> */
  98   struct fpstate *fpstatep;
  99   char buf[sizeof (struct fpstate) + 2 * sizeof (int)];
 100   unsigned int uaddr;
 101   char fpvalid = 0;
 102   unsigned int rounded_addr;
 103   unsigned int rounded_size;
 104   extern int corechan;
 105   int skip;
 106
 107   uaddr = (char *)&u.u_fpvalid - (char *)&u;
 108   if (target_has_execution)
 109     {
 110       unsigned int data;
 111       unsigned int mask;
 112
 113       rounded_addr = uaddr & -sizeof (int);
 114       data = ptrace (3, inferior_pid, (PTRACE_ARG3_TYPE) rounded_addr, 0);
 115       mask = 0xff << ((uaddr - rounded_addr) * 8);
 116
 117       fpvalid = ((data & mask) != 0);
 118     }
 119 #if 0
 120   else
 121     {
 122       if (lseek (corechan, uaddr, 0) < 0)
 123         perror ("seek on core file");
 124       if (myread (corechan, &fpvalid, 1) < 0)
 125         perror ("read on core file");
 126
 127     }
 128 #endif  /* no core support yet */
 129
 130   if (fpvalid == 0)
 131     {
 132       printf ("no floating point status saved\n");
 133       return;
 134     }
 135
 136   uaddr = (char *)&U_FPSTATE(u) - (char *)&u;
 137   if (target_has_execution)
 138     {
 139       int *ip;
 140
 141       rounded_addr = uaddr & -sizeof (int);
 142       rounded_size = (((uaddr + sizeof (struct fpstate)) - uaddr) +
 143                       sizeof (int) - 1) / sizeof (int);
 144       skip = uaddr - rounded_addr;
 145
 146       ip = (int *)buf;
 147       for (i = 0; i < rounded_size; i++)
 148         {
 149           *ip++ = ptrace (3, inferior_pid, (PTRACE_ARG3_TYPE) rounded_addr, 0);
 150           rounded_addr += sizeof (int);
 151         }
 152     }
 153 #if 0
 154   else
 155     {
 156       if (lseek (corechan, uaddr, 0) < 0)
 157         perror_with_name ("seek on core file");
 158       if (myread (corechan, buf, sizeof (struct fpstate)) < 0)
 159         perror_with_name ("read from core file");
 160       skip = 0;
 161     }
 162 #endif  /* 0 */
 163
 164   fpstatep = (struct fpstate *)(buf + skip);
 165   print_387_status (fpstatep->status, (struct env387 *)fpstatep->state);
 166 }
 167
 168 #endif /* never */