gdb/i386v4-nat.c

   1 /* Native-dependent code for SVR4 Unix running on i386's.
   2    Copyright 1988, 1989, 1991, 1992, 1996, 1997, 1998, 1999, 2000,
   3    2001, 2002
   4    Free Software Foundation, Inc.
   5
   6    This file is part of GDB.
   7
   8    This program is free software; you can redistribute it and/or modify
   9    it under the terms of the GNU General Public License as published by
  10    the Free Software Foundation; either version 2 of the License, or
  11    (at your option) any later version.
  12
  13    This program is distributed in the hope that it will be useful,
  14    but WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16    GNU General Public License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with this program; if not, write to the Free Software
  20    Foundation, Inc., 59 Temple Place - Suite 330,
  21    Boston, MA 02111-1307, USA.  */
  22
  23 #include "defs.h"
  24 #include "value.h"
  25 #include "inferior.h"
  26 #include "regcache.h"
  27
  28 #ifdef HAVE_SYS_REG_H
  29 #include <sys/reg.h>
  30 #endif
  31
  32 #include "i386-tdep.h"
  33 #include "i387-tdep.h"
  34
  35 #ifdef HAVE_SYS_PROCFS_H
  36
  37 #include <sys/procfs.h>
  38
  39 /* Prototypes for supply_gregset etc. */
  40 #include "gregset.h"
  41
  42 /* The `/proc' interface divides the target machine's register set up
  43    into two different sets, the general purpose register set (gregset)
  44    and the floating-point register set (fpregset).  For each set,
  45    there is an ioctl to get the current register set and another ioctl
  46    to set the current values.
  47
  48    The actual structure passed through the ioctl interface is, of
  49    course, naturally machine dependent, and is different for each set
  50    of registers.  For the i386 for example, the general-purpose
  51    register set is typically defined by:
  52
  53    typedef int gregset_t[19];           (in <sys/regset.h>)
  54
  55    #define GS   0                       (in <sys/reg.h>)
  56    #define FS   1
  57    ...
  58    #define UESP 17
  59    #define SS   18
  60
  61    and the floating-point set by:
  62
  63    typedef struct fpregset   {
  64            union {
  65                    struct fpchip_state            // fp extension state //
  66                    {
  67                            int     state[27];     // 287/387 saved state //
  68                            int     status;        // status word saved at //
  69                                                   // exception //
  70                    } fpchip_state;
  71                    struct fp_emul_space           // for emulators //
  72                    {
  73                            char    fp_emul[246];
  74                            char    fp_epad[2];
  75                    } fp_emul_space;
  76                    int     f_fpregs[62];          // union of the above //
  77            } fp_reg_set;
  78            long            f_wregs[33];           // saved weitek state //
  79    } fpregset_t;
  80
  81    Incidentally fpchip_state contains the FPU state in the same format
  82    as used by the "fsave" instruction, and that's the only thing we
  83    support here.  I don't know how the emulator stores it state.  The
  84    Weitek stuff definitely isn't supported.
  85
  86    The routines defined here, provide the packing and unpacking of
  87    gregset_t and fpregset_t formatted data.  */
  88
  89 #ifdef HAVE_GREGSET_T
  90
  91 /* Mapping between the general-purpose registers in `/proc'
  92    format and GDB's register array layout.  */
  93 static int regmap[] =
  94 {
  95   EAX, ECX, EDX, EBX,
  96   UESP, EBP, ESI, EDI,
  97   EIP, EFL, CS, SS,
  98   DS, ES, FS, GS,
  99 };
 100
 101 /* Fill GDB's register array with the general-purpose register values
 102    in *GREGSETP.  */
 103
 104 void
 105 supply_gregset (gregset_t *gregsetp)
 106 {
 107   greg_t *regp = (greg_t *) gregsetp;
 108   int i;
 109
 110   for (i = 0; i < I386_NUM_GREGS; i++)
 111     supply_register (i, (char *) (regp + regmap[i]));
 112 }
 113
 114 /* Fill register REGNO (if it is a general-purpose register) in
 115    *GREGSETPS with the value in GDB's register array.  If REGNO is -1,
 116    do this for all registers.  */
 117
 118 void
 119 fill_gregset (gregset_t *gregsetp, int regno)
 120 {
 121   greg_t *regp = (greg_t *) gregsetp;
 122   int i;
 123
 124   for (i = 0; i < I386_NUM_GREGS; i++)
 125     if (regno == -1 || regno == i)
 126       regcache_collect (i, regp + regmap[i]);
 127 }
 128
 129 #endif /* HAVE_GREGSET_T */
 130
 131 #ifdef HAVE_FPREGSET_T
 132
 133 /* Fill GDB's register array with the floating-point register values in
 134    *FPREGSETP.  */
 135
 136 void
 137 supply_fpregset (fpregset_t *fpregsetp)
 138 {
 139   if (FP0_REGNUM == 0)
 140     return;
 141
 142   i387_supply_fsave ((char *) fpregsetp);
 143 }
 144
 145 /* Fill register REGNO (if it is a floating-point register) in
 146    *FPREGSETP with the value in GDB's register array.  If REGNO is -1,
 147    do this for all registers.  */
 148
 149 void
 150 fill_fpregset (fpregset_t *fpregsetp, int regno)
 151 {
 152   if (FP0_REGNUM == 0)
 153     return;
 154
 155   i387_fill_fsave ((char *) fpregsetp, regno);
 156 }
 157
 158 #endif /* HAVE_FPREGSET_T */
 159
 160 #endif /* HAVE_SYS_PROCFS_H */