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, 2001 Free Software
   3    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 2 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, write to the Free Software
  19    Foundation, Inc., 59 Temple Place - Suite 330,
  20    Boston, MA 02111-1307, USA.  */
  21
  22 #include "defs.h"
  23 #include "value.h"
  24 #include "inferior.h"
  25 #include "regcache.h"
  26
  27 #ifdef HAVE_SYS_REG_H
  28 #include <sys/reg.h>
  29 #endif
  30
  31
  32 #ifdef HAVE_SYS_PROCFS_H
  33
  34 #include <sys/procfs.h>
  35
  36 /* Prototypes for supply_gregset etc. */
  37 #include "gregset.h"
  38
  39 /*  The /proc interface divides the target machine's register set up into
  40    two different sets, the general register set (gregset) and the floating
  41    point register set (fpregset).  For each set, there is an ioctl to get
  42    the current register set and another ioctl to set the current values.
  43
  44    The actual structure passed through the ioctl interface is, of course,
  45    naturally machine dependent, and is different for each set of registers.
  46    For the i386 for example, the general register set is typically defined
  47    by:
  48
  49    typedef int gregset_t[19];           (in <sys/regset.h>)
  50
  51    #define GS   0                       (in <sys/reg.h>)
  52    #define FS   1
  53    ...
  54    #define UESP 17
  55    #define SS   18
  56
  57    and the floating point set by:
  58
  59    typedef struct fpregset
  60    {
  61    union
  62    {
  63    struct fpchip_state  // fp extension state //
  64    {
  65    int state[27];       // 287/387 saved state //
  66    int status;          // status word saved at exception //
  67    } fpchip_state;
  68    struct fp_emul_space // for emulators //
  69    {
  70    char fp_emul[246];
  71    char fp_epad[2];
  72    } fp_emul_space;
  73    int f_fpregs[62];    // union of the above //
  74    } fp_reg_set;
  75    long f_wregs[33];            // saved weitek state //
  76    } fpregset_t;
  77
  78    These routines provide the packing and unpacking of gregset_t and
  79    fpregset_t formatted data.
  80
  81  */
  82
  83 #ifdef HAVE_GREGSET_T
  84
  85 /* This is a duplicate of the table in i386-xdep.c. */
  86
  87 static int regmap[] =
  88 {
  89   EAX, ECX, EDX, EBX,
  90   UESP, EBP, ESI, EDI,
  91   EIP, EFL, CS, SS,
  92   DS, ES, FS, GS,
  93 };
  94
  95 /* Prototypes for local functions */
  96
  97 void fill_gregset (gregset_t *, int);
  98
  99 void supply_gregset (gregset_t *);
 100
 101 void supply_fpregset (fpregset_t *);
 102
 103 void fill_fpregset (fpregset_t *, int);
 104
 105
 106 /*  FIXME:  These routine absolutely depends upon (NUM_REGS - NUM_FREGS)
 107    being less than or equal to the number of registers that can be stored
 108    in a gregset_t.  Note that with the current scheme there will typically
 109    be more registers actually stored in a gregset_t that what we know
 110    about.  This is bogus and should be fixed. */
 111
 112 /*  Given a pointer to a general register set in /proc format (gregset_t *),
 113    unpack the register contents and supply them as gdb's idea of the current
 114    register values. */
 115
 116 void
 117 supply_gregset (gregset_t *gregsetp)
 118 {
 119   register int regi;
 120   register greg_t *regp = (greg_t *) gregsetp;
 121   extern int regmap[];
 122
 123   for (regi = 0; regi < (NUM_REGS - NUM_FREGS); regi++)
 124     {
 125       supply_register (regi, (char *) (regp + regmap[regi]));
 126     }
 127 }
 128
 129 void
 130 fill_gregset (gregset_t *gregsetp, int regno)
 131 {
 132   int regi;
 133   register greg_t *regp = (greg_t *) gregsetp;
 134   extern int regmap[];
 135
 136   for (regi = 0; regi < (NUM_REGS - NUM_FREGS); regi++)
 137     {
 138       if ((regno == -1) || (regno == regi))
 139         {
 140           *(regp + regmap[regi]) = *(int *) &registers[REGISTER_BYTE (regi)];
 141         }
 142     }
 143 }
 144
 145 #endif /* HAVE_GREGSET_T */
 146
 147 #if defined (HAVE_FPREGSET_T)
 148
 149 /*  Given a pointer to a floating point register set in /proc format
 150    (fpregset_t *), unpack the register contents and supply them as gdb's
 151    idea of the current floating point register values. */
 152
 153 /* FIXME: Assumes that fpregsetp contains an i387 FSAVE area. */
 154 static const int freg_offset_map[] =
 155 {
 156 #if !defined(FPREGSET_FSAVE_OFFSET)
 157 #define FPREGSET_FSAVE_OFFSET   0
 158 #endif
 159   FPREGSET_FSAVE_OFFSET + 28 + 0 * 10,
 160   FPREGSET_FSAVE_OFFSET + 28 + 1 * 10,
 161   FPREGSET_FSAVE_OFFSET + 28 + 2 * 10,
 162   FPREGSET_FSAVE_OFFSET + 28 + 3 * 10,
 163   FPREGSET_FSAVE_OFFSET + 28 + 4 * 10,
 164   FPREGSET_FSAVE_OFFSET + 28 + 5 * 10,
 165   FPREGSET_FSAVE_OFFSET + 28 + 6 * 10,
 166   FPREGSET_FSAVE_OFFSET + 28 + 7 * 10,
 167   FPREGSET_FSAVE_OFFSET + 0,
 168   FPREGSET_FSAVE_OFFSET + 4,
 169   FPREGSET_FSAVE_OFFSET + 8,
 170   FPREGSET_FSAVE_OFFSET + 16,
 171   FPREGSET_FSAVE_OFFSET + 12,
 172   FPREGSET_FSAVE_OFFSET + 24,
 173   FPREGSET_FSAVE_OFFSET + 20,
 174   FPREGSET_FSAVE_OFFSET + 16
 175 };
 176
 177 void
 178 supply_fpregset (fpregset_t *fpregsetp)
 179 {
 180   int regi;
 181
 182   if (NUM_FREGS == 0)
 183     return;
 184   for (regi = FP0_REGNUM; regi <= LAST_FPU_CTRL_REGNUM; regi++)
 185     {
 186       char tbuf[4];
 187       ULONGEST tval;
 188       char *from = (char *) fpregsetp + freg_offset_map[regi - FP0_REGNUM];
 189
 190       if (regi == FCS_REGNUM)
 191         {
 192           tval = extract_unsigned_integer (from, 4) & 0xffff;
 193           store_unsigned_integer (tbuf, 4, tval);
 194           supply_register (regi, tbuf);
 195         }
 196       else if (regi == FOP_REGNUM)
 197         {
 198           tval = (extract_unsigned_integer (from, 4) >> 16) & ((1 << 11) - 1);
 199           store_unsigned_integer (tbuf, 4, tval);
 200           supply_register (regi, tbuf);
 201         }
 202       else
 203         supply_register (regi, from);
 204     }
 205 }
 206
 207 /*  Given a pointer to a floating point register set in /proc format
 208    (fpregset_t *), update the register specified by REGNO from gdb's idea
 209    of the current floating point register set.  If REGNO is -1, update
 210    them all. */
 211
 212 void
 213 fill_fpregset (fpregset_t *fpregsetp, int regno)
 214 {
 215   int regi;
 216
 217   if (NUM_FREGS == 0)
 218     return;
 219   for (regi = FP0_REGNUM; regi <= LAST_FPU_CTRL_REGNUM; regi++)
 220     {
 221       if ((regno == -1) || (regno == regi))
 222         {
 223           char *to = (char *) fpregsetp + freg_offset_map[regi - FP0_REGNUM];
 224           char *from = (char *) &registers[REGISTER_BYTE (regi)];
 225           ULONGEST valto;
 226           ULONGEST valfrom;
 227
 228           if (regi == FCS_REGNUM)
 229             {
 230               valto = extract_unsigned_integer (to, 4);
 231               valfrom = extract_unsigned_integer (from, 4);
 232               valto = (valto & ~0xffff) | (valfrom & 0xffff);
 233               store_unsigned_integer (to, 4, valto);
 234             }
 235           else if (regi == FOP_REGNUM)
 236             {
 237               valto = extract_unsigned_integer (to, 4);
 238               valfrom = extract_unsigned_integer (from, 4);
 239               valto = (valto & 0xffff) | ((valfrom & ((1 << 11) - 1)) << 16);
 240               store_unsigned_integer (to, 4, valto);
 241             }
 242           else
 243             {
 244               memcpy (to, from, REGISTER_RAW_SIZE (regi));
 245             }
 246         }
 247     }
 248 }
 249
 250 #endif /* defined (HAVE_FPREGSET_T) */
 251
 252 #endif /* HAVE_SYS_PROCFS_H */