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