gdb/i386v4-nat.c

   1 /* Native-dependent code for Unix SVR4 running on i386's.
   2
   3    Copyright (C) 1988-2016 Free Software Foundation, Inc.
   4
   5    This file is part of GDB.
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 3 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  19
  20 #include "defs.h"
  21 #include "value.h"
  22 #include "inferior.h"
  23 #include "regcache.h"
  24
  25 #ifdef HAVE_SYS_REG_H
  26 #include <sys/reg.h>
  27 #endif
  28
  29 #include "i386-tdep.h"
  30 #include "i387-tdep.h"
  31
  32 #ifdef HAVE_SYS_PROCFS_H
  33
  34 #include <sys/procfs.h>
  35
  36 /* We must not compile this code for 64-bit Solaris x86.  */
  37 #if !defined (PR_MODEL_NATIVE) || (PR_MODEL_NATIVE == PR_MODEL_ILP32)
  38
  39 #include "gregset.h"
  40
  41 /* The `/proc' interface divides the target machine's register set up
  42    into two different sets, the general purpose register set (gregset)
  43    and the floating-point register set (fpregset).  For each set,
  44    there is an ioctl to get the current register set and another ioctl
  45    to set the current values.
  46
  47    The actual structure passed through the ioctl interface is, of
  48    course, naturally machine dependent, and is different for each set
  49    of registers.  For the i386 for example, the general-purpose
  50    register set is typically defined by:
  51
  52    typedef int gregset_t[19];           (in <sys/regset.h>)
  53
  54    #define GS   0                       (in <sys/reg.h>)
  55    #define FS   1
  56    ...
  57    #define UESP 17
  58    #define SS   18
  59
  60    and the floating-point set by:
  61
  62    typedef struct fpregset   {
  63            union {
  64                    struct fpchip_state            // fp extension state //
  65                    {
  66                            int     state[27];     // 287/387 saved state //
  67                            int     status;        // status word saved at //
  68                                                   // exception //
  69                    } fpchip_state;
  70                    struct fp_emul_space           // for emulators //
  71                    {
  72                            char    fp_emul[246];
  73                            char    fp_epad[2];
  74                    } fp_emul_space;
  75                    int     f_fpregs[62];          // union of the above //
  76            } fp_reg_set;
  77            long            f_wregs[33];           // saved weitek state //
  78    } fpregset_t;
  79
  80    Incidentally fpchip_state contains the FPU state in the same format
  81    as used by the "fsave" instruction, and that's the only thing we
  82    support here.  I don't know how the emulator stores it state.  The
  83    Weitek stuff definitely isn't supported.
  84
  85    The routines defined here, provide the packing and unpacking of
  86    gregset_t and fpregset_t formatted data.  */
  87
  88 #ifdef HAVE_GREGSET_T
  89
  90 /* Mapping between the general-purpose registers in `/proc'
  91    format and GDB's register array layout.  */
  92 static int regmap[] =
  93 {
  94   EAX, ECX, EDX, EBX,
  95   UESP, EBP, ESI, EDI,
  96   EIP, EFL, CS, SS,
  97   DS, ES, FS, GS
  98 };
  99
 100 /* Fill GDB's register array with the general-purpose register values
 101    in *GREGSETP.  */
 102
 103 void
 104 supply_gregset (struct regcache *regcache, const gregset_t *gregsetp)
 105 {
 106   const greg_t *regp = (const greg_t *) gregsetp;
 107   int regnum;
 108
 109   for (regnum = 0; regnum < I386_NUM_GREGS; regnum++)
 110     regcache_raw_supply (regcache, regnum, regp + regmap[regnum]);
 111 }
 112
 113 /* Fill register REGNUM (if it is a general-purpose register) in
 114    *GREGSETPS with the value in GDB's register array.  If REGNUM is -1,
 115    do this for all registers.  */
 116
 117 void
 118 fill_gregset (const struct regcache *regcache,
 119               gregset_t *gregsetp, int regnum)
 120 {
 121   greg_t *regp = (greg_t *) gregsetp;
 122   int i;
 123
 124   for (i = 0; i < I386_NUM_GREGS; i++)
 125     if (regnum == -1 || regnum == i)
 126       regcache_raw_collect (regcache, 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 (struct regcache *regcache, const fpregset_t *fpregsetp)
 138 {
 139   if (gdbarch_fp0_regnum (get_regcache_arch (regcache)) == 0)
 140     return;
 141
 142   i387_supply_fsave (regcache, -1, 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 (const struct regcache *regcache,
 151                fpregset_t *fpregsetp, int regno)
 152 {
 153   if (gdbarch_fp0_regnum (get_regcache_arch (regcache)) == 0)
 154     return;
 155
 156   i387_collect_fsave (regcache, regno, fpregsetp);
 157 }
 158
 159 #endif /* HAVE_FPREGSET_T */
 160
 161 #endif /* not 64-bit.  */
 162
 163 #endif /* HAVE_SYS_PROCFS_H */