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