gdb/i386v4-nat.c

   1 /* Native-dependent code for SVR4 Unix running on i386's, for GDB.
   2    Copyright 1988, 1989, 1991, 1992, 1996 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
  19
  20 #ifdef HAVE_SYS_PROCFS_H
  21
  22 #include "defs.h"
  23 #include <sys/procfs.h>
  24
  25 /*  The /proc interface divides the target machine's register set up into
  26     two different sets, the general register set (gregset) and the floating
  27     point register set (fpregset).  For each set, there is an ioctl to get
  28     the current register set and another ioctl to set the current values.
  29
  30     The actual structure passed through the ioctl interface is, of course,
  31     naturally machine dependent, and is different for each set of registers.
  32     For the i386 for example, the general register set is typically defined
  33     by:
  34
  35         typedef int gregset_t[19];              (in <sys/regset.h>)
  36
  37         #define GS      0                       (in <sys/reg.h>)
  38         #define FS      1
  39         ...
  40         #define UESP    17
  41         #define SS      18
  42
  43     and the floating point set by:
  44
  45         typedef struct fpregset
  46           {
  47             union
  48               {
  49                 struct fpchip_state     // fp extension state //
  50                 {
  51                   int state[27];        // 287/387 saved state //
  52                   int status;           // status word saved at exception //
  53                 } fpchip_state;
  54                 struct fp_emul_space    // for emulators //
  55                 {
  56                   char fp_emul[246];
  57                   char fp_epad[2];
  58                 } fp_emul_space;
  59                 int f_fpregs[62];       // union of the above //
  60               } fp_reg_set;
  61             long f_wregs[33];           // saved weitek state //
  62         } fpregset_t;
  63
  64     These routines provide the packing and unpacking of gregset_t and
  65     fpregset_t formatted data.
  66
  67  */
  68
  69 #ifdef HAVE_GREGSET_T
  70
  71 /* This is a duplicate of the table in i386-xdep.c. */
  72
  73 static int regmap[] =
  74 {
  75   EAX, ECX, EDX, EBX,
  76   UESP, EBP, ESI, EDI,
  77   EIP, EFL, CS, SS,
  78   DS, ES, FS, GS,
  79 };
  80
  81
  82 /*  FIXME:  These routine absolutely depends upon (NUM_REGS - NUM_FREGS)
  83     being less than or equal to the number of registers that can be stored
  84     in a gregset_t.  Note that with the current scheme there will typically
  85     be more registers actually stored in a gregset_t that what we know
  86     about.  This is bogus and should be fixed. */
  87
  88 /*  Given a pointer to a general register set in /proc format (gregset_t *),
  89     unpack the register contents and supply them as gdb's idea of the current
  90     register values. */
  91
  92 void
  93 supply_gregset (gregsetp)
  94      gregset_t *gregsetp;
  95 {
  96   register int regi;
  97   register greg_t *regp = (greg_t *) gregsetp;
  98   extern int regmap[];
  99
 100   for (regi = 0 ; regi < (NUM_REGS - NUM_FREGS) ; regi++)
 101     {
 102       supply_register (regi, (char *) (regp + regmap[regi]));
 103     }
 104 }
 105
 106 void
 107 fill_gregset (gregsetp, regno)
 108      gregset_t *gregsetp;
 109      int regno;
 110 {
 111   int regi;
 112   register greg_t *regp = (greg_t *) gregsetp;
 113   extern char registers[];
 114   extern int regmap[];
 115
 116   for (regi = 0 ; regi < (NUM_REGS - NUM_FREGS) ; regi++)
 117     {
 118       if ((regno == -1) || (regno == regi))
 119         {
 120           *(regp + regmap[regi]) = *(int *) &registers[REGISTER_BYTE (regi)];
 121         }
 122     }
 123 }
 124
 125 #endif  /* HAVE_GREGSET_T */
 126
 127 #if defined (FP0_REGNUM) && defined (HAVE_FPREGSET_T)
 128
 129 /*  Given a pointer to a floating point register set in /proc format
 130     (fpregset_t *), unpack the register contents and supply them as gdb's
 131     idea of the current floating point register values. */
 132
 133 void
 134 supply_fpregset (fpregsetp)
 135      fpregset_t *fpregsetp;
 136 {
 137   register int regi;
 138
 139   /* FIXME: see m68k-tdep.c for an example, for the m68k. */
 140 }
 141
 142 /*  Given a pointer to a floating point register set in /proc format
 143     (fpregset_t *), update the register specified by REGNO from gdb's idea
 144     of the current floating point register set.  If REGNO is -1, update
 145     them all. */
 146
 147 void
 148 fill_fpregset (fpregsetp, regno)
 149      fpregset_t *fpregsetp;
 150      int regno;
 151 {
 152   int regi;
 153   char *to;
 154   char *from;
 155   extern char registers[];
 156
 157   /* FIXME: see m68k-tdep.c for an example, for the m68k. */
 158 }
 159
 160 #endif  /* defined (FP0_REGNUM) && defined (HAVE_FPREGSET_T) */
 161
 162 #endif  /* HAVE_SYS_PROCFS_H */