gdb/i386v4-nat.c

   1 /* Native-dependent code for SVR4 Unix running on i386's, for GDB.
   2    Copyright 1988, 1989, 1991, 1992, 1996, 1998 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 #include "defs.h"
  21 #include "value.h"
  22
  23 #ifdef HAVE_SYS_REG_H
  24 #include <sys/reg.h>
  25 #endif
  26
  27
  28 #ifdef HAVE_SYS_PROCFS_H
  29
  30 #include <sys/procfs.h>
  31
  32 /*  The /proc interface divides the target machine's register set up into
  33     two different sets, the general register set (gregset) and the floating
  34     point register set (fpregset).  For each set, there is an ioctl to get
  35     the current register set and another ioctl to set the current values.
  36
  37     The actual structure passed through the ioctl interface is, of course,
  38     naturally machine dependent, and is different for each set of registers.
  39     For the i386 for example, the general register set is typically defined
  40     by:
  41
  42         typedef int gregset_t[19];              (in <sys/regset.h>)
  43
  44         #define GS      0                       (in <sys/reg.h>)
  45         #define FS      1
  46         ...
  47         #define UESP    17
  48         #define SS      18
  49
  50     and the floating point set by:
  51
  52         typedef struct fpregset
  53           {
  54             union
  55               {
  56                 struct fpchip_state     // fp extension state //
  57                 {
  58                   int state[27];        // 287/387 saved state //
  59                   int status;           // status word saved at exception //
  60                 } fpchip_state;
  61                 struct fp_emul_space    // for emulators //
  62                 {
  63                   char fp_emul[246];
  64                   char fp_epad[2];
  65                 } fp_emul_space;
  66                 int f_fpregs[62];       // union of the above //
  67               } fp_reg_set;
  68             long f_wregs[33];           // saved weitek state //
  69         } fpregset_t;
  70
  71     These routines provide the packing and unpacking of gregset_t and
  72     fpregset_t formatted data.
  73
  74  */
  75
  76 #ifdef HAVE_GREGSET_T
  77
  78 /* This is a duplicate of the table in i386-xdep.c. */
  79
  80 static int regmap[] =
  81 {
  82   EAX, ECX, EDX, EBX,
  83   UESP, EBP, ESI, EDI,
  84   EIP, EFL, CS, SS,
  85   DS, ES, FS, GS,
  86 };
  87
  88 /* Prototypes for local functions */
  89
  90 void fill_gregset PARAMS ((gregset_t *, int));
  91
  92 void supply_gregset PARAMS ((gregset_t *));
  93
  94 void supply_fpregset PARAMS ((fpregset_t *));
  95
  96 void fill_fpregset PARAMS ((fpregset_t *, int));
  97
  98
  99 /*  FIXME:  These routine absolutely depends upon (NUM_REGS - NUM_FREGS)
 100     being less than or equal to the number of registers that can be stored
 101     in a gregset_t.  Note that with the current scheme there will typically
 102     be more registers actually stored in a gregset_t that what we know
 103     about.  This is bogus and should be fixed. */
 104
 105 /*  Given a pointer to a general register set in /proc format (gregset_t *),
 106     unpack the register contents and supply them as gdb's idea of the current
 107     register values. */
 108
 109 void
 110 supply_gregset (gregsetp)
 111      gregset_t *gregsetp;
 112 {
 113   register int regi;
 114   register greg_t *regp = (greg_t *) gregsetp;
 115   extern int regmap[];
 116
 117   for (regi = 0 ; regi < (NUM_REGS - NUM_FREGS) ; regi++)
 118     {
 119       supply_register (regi, (char *) (regp + regmap[regi]));
 120     }
 121 }
 122
 123 void
 124 fill_gregset (gregsetp, regno)
 125      gregset_t *gregsetp;
 126      int regno;
 127 {
 128   int regi;
 129   register greg_t *regp = (greg_t *) gregsetp;
 130   extern char registers[];
 131   extern int regmap[];
 132
 133   for (regi = 0 ; regi < (NUM_REGS - NUM_FREGS) ; regi++)
 134     {
 135       if ((regno == -1) || (regno == regi))
 136         {
 137           *(regp + regmap[regi]) = *(int *) &registers[REGISTER_BYTE (regi)];
 138         }
 139     }
 140 }
 141
 142 #endif  /* HAVE_GREGSET_T */
 143
 144 #if defined (FP0_REGNUM) && defined (HAVE_FPREGSET_T)
 145
 146 /*  Given a pointer to a floating point register set in /proc format
 147     (fpregset_t *), unpack the register contents and supply them as gdb's
 148     idea of the current floating point register values. */
 149
 150 void
 151 supply_fpregset (fpregsetp)
 152      fpregset_t *fpregsetp;
 153 {
 154   /* FIXME: see m68k-tdep.c for an example, for the m68k. */
 155 }
 156
 157 /*  Given a pointer to a floating point register set in /proc format
 158     (fpregset_t *), update the register specified by REGNO from gdb's idea
 159     of the current floating point register set.  If REGNO is -1, update
 160     them all. */
 161
 162 void
 163 fill_fpregset (fpregsetp, regno)
 164      fpregset_t *fpregsetp;
 165      int regno;
 166 {
 167   /* FIXME: see m68k-tdep.c for an example, for the m68k. */
 168 }
 169
 170 #endif  /* defined (FP0_REGNUM) && defined (HAVE_FPREGSET_T) */
 171
 172 #endif  /* HAVE_SYS_PROCFS_H */