gdb/sun386-nat.c

   1 /* Native support for Sun 386i's for GDB, the GNU debugger.
   2    Copyright 1986, 1987, 1989, 1991, 1992, 1993, 1995, 1999, 2000, 2001
   3    Free Software Foundation, Inc.
   4    Changes for sun386i by Jean Daniel Fekete (jdf@litp.univ-p6-7.fr),
   5    C2V Paris, April 89.
   6
   7    This file is part of GDB.
   8
   9    This program is free software; you can redistribute it and/or modify
  10    it under the terms of the GNU General Public License as published by
  11    the Free Software Foundation; either version 2 of the License, or
  12    (at your option) any later version.
  13
  14    This program is distributed in the hope that it will be useful,
  15    but WITHOUT ANY WARRANTY; without even the implied warranty of
  16    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17    GNU General Public License for more details.
  18
  19    You should have received a copy of the GNU General Public License
  20    along with this program; if not, write to the Free Software
  21    Foundation, Inc., 59 Temple Place - Suite 330,
  22    Boston, MA 02111-1307, USA.  */
  23
  24 #include "defs.h"
  25 #include "frame.h"
  26 #include "inferior.h"
  27 #include "gdbcore.h"
  28 #include "regcache.h"
  29
  30 #include <sys/param.h>
  31 #include <sys/dir.h>
  32 #include <sys/user.h>
  33 #include <signal.h>
  34 #include <sys/ioctl.h>
  35 #include <fcntl.h>
  36
  37 #include <sys/ptrace.h>
  38 #include <machine/reg.h>
  39
  40 #include <sys/file.h>
  41 #include "gdb_stat.h"
  42 #include <sys/core.h>
  43 \f
  44
  45 /* Machine-dependent code which would otherwise be in corefile.c */
  46 /* Work with core files, for GDB. */
  47 \f
  48
  49 void
  50 core_file_command (char *filename, int from_tty)
  51 {
  52   int val;
  53
  54   /* Discard all vestiges of any previous core file
  55      and mark data and stack spaces as empty.  */
  56
  57   if (corefile)
  58     xfree (corefile);
  59   corefile = 0;
  60
  61   if (corechan >= 0)
  62     close (corechan);
  63   corechan = -1;
  64
  65   data_start = 0;
  66   data_end = 0;
  67   stack_start = STACK_END_ADDR;
  68   stack_end = STACK_END_ADDR;
  69
  70   /* Now, if a new core file was specified, open it and digest it.  */
  71
  72   if (filename)
  73     {
  74       filename = tilde_expand (filename);
  75       make_cleanup (xfree, filename);
  76
  77       if (have_inferior_p ())
  78         error ("To look at a core file, you must kill the program with \"kill\".");
  79       corechan = open (filename, O_RDONLY, 0);
  80       if (corechan < 0)
  81         perror_with_name (filename);
  82
  83       {
  84         struct core corestr;
  85
  86         val = myread (corechan, &corestr, sizeof corestr);
  87         if (val < 0)
  88           perror_with_name (filename);
  89         if (corestr.c_magic != CORE_MAGIC)
  90           error ("\"%s\" does not appear to be a core dump file (magic 0x%x, expected 0x%x)",
  91                  filename, corestr.c_magic, (int) CORE_MAGIC);
  92         else if (sizeof (struct core) != corestr.c_len)
  93             error ("\"%s\" has an invalid struct core length (%d, expected %d)",
  94                    filename, corestr.c_len, (int) sizeof (struct core));
  95
  96         data_start = exec_data_start;
  97         data_end = data_start + corestr.c_dsize;
  98         stack_start = stack_end - corestr.c_ssize;
  99         data_offset = sizeof corestr;
 100         stack_offset = sizeof corestr + corestr.c_dsize;
 101
 102         memcpy (registers, &corestr.c_regs, sizeof corestr.c_regs);
 103
 104         memcpy (&registers[REGISTER_BYTE (FP0_REGNUM)],
 105                 corestr.c_fpu.f_fpstatus.f_st,
 106                 sizeof corestr.c_fpu.f_fpstatus.f_st);
 107         memcpy (&registers[REGISTER_BYTE (FPC_REGNUM)],
 108                 &corestr.c_fpu.f_fpstatus.f_ctrl,
 109                 sizeof corestr.c_fpu.f_fpstatus -
 110                 sizeof corestr.c_fpu.f_fpstatus.f_st);
 111
 112         /* the struct aouthdr of sun coff is not the struct exec stored
 113            in the core file. */
 114         memcpy (&core_aouthdr, &corestr.c_aouthdr, sizeof (struct exec));
 115 #ifndef COFF_ENCAPSULATE
 116         core_aouthdr.magic = corestr.c_aouthdr.a_info;
 117         core_aouthdr.vstamp = /*SUNVERSION */ 31252;
 118 #endif
 119         printf_unfiltered ("Core file is from \"%s\".\n", corestr.c_cmdname);
 120         if (corestr.c_signo > 0)
 121           printf_unfiltered ("Program terminated with signal %d, %s.\n",
 122                          corestr.c_signo, safe_strsignal (corestr.c_signo));
 123       }
 124       if (filename[0] == '/')
 125         corefile = savestring (filename, strlen (filename));
 126       else
 127         {
 128           corefile = concat (current_directory, "/", filename, NULL);
 129         }
 130
 131       flush_cached_frames ();
 132       select_frame (get_current_frame (), 0);
 133
 134       validate_files ();
 135     }
 136   else if (from_tty)
 137     printf_unfiltered ("No core file now.\n");
 138 }
 139
 140 i387_to_double (char *from, char *to)
 141 {
 142   long *lp;
 143   /* push extended mode on 387 stack, then pop in double mode
 144
 145    * first, set exception masks so no error is generated -
 146    * number will be rounded to inf or 0, if necessary
 147    */
 148   asm ("pushl %eax");           /* grab a stack slot */
 149   asm ("fstcw (%esp)");         /* get 387 control word */
 150   asm ("movl (%esp),%eax");     /* save old value */
 151   asm ("orl $0x3f,%eax");       /* mask all exceptions */
 152   asm ("pushl %eax");
 153   asm ("fldcw (%esp)");         /* load new value into 387 */
 154
 155   asm ("movl 8(%ebp),%eax");
 156   asm ("fldt (%eax)");          /* push extended number on 387 stack */
 157   asm ("fwait");
 158   asm ("movl 12(%ebp),%eax");
 159   asm ("fstpl (%eax)");         /* pop double */
 160   asm ("fwait");
 161
 162   asm ("popl %eax");            /* flush modified control word */
 163   asm ("fnclex");               /* clear exceptions */
 164   asm ("fldcw (%esp)");         /* restore original control word */
 165   asm ("popl %eax");            /* flush saved copy */
 166 }
 167
 168 double_to_i387 (char *from, char *to)
 169 {
 170   /* push double mode on 387 stack, then pop in extended mode
 171    * no errors are possible because every 64-bit pattern
 172    * can be converted to an extended
 173    */
 174   asm ("movl 8(%ebp),%eax");
 175   asm ("fldl (%eax)");
 176   asm ("fwait");
 177   asm ("movl 12(%ebp),%eax");
 178   asm ("fstpt (%eax)");
 179   asm ("fwait");
 180 }
 181
 182 void
 183 fetch_inferior_registers (int regno)
 184 {
 185   struct regs inferior_registers;
 186   struct fp_state inferior_fp_registers;
 187
 188   registers_fetched ();
 189
 190   ptrace (PTRACE_GETREGS, inferior_pid,
 191           (PTRACE_ARG3_TYPE) & inferior_registers);
 192   ptrace (PTRACE_GETFPREGS, inferior_pid,
 193           (PTRACE_ARG3_TYPE) & inferior_fp_registers);
 194
 195   memcpy (registers, &inferior_registers, sizeof inferior_registers);
 196
 197   memcpy (&registers[REGISTER_BYTE (FP0_REGNUM)], inferior_fp_registers.f_st,
 198           sizeof inferior_fp_registers.f_st);
 199   memcpy (&registers[REGISTER_BYTE (FPC_REGNUM)],
 200           &inferior_fp_registers.f_ctrl,
 201           sizeof inferior_fp_registers - sizeof inferior_fp_registers.f_st);
 202 }
 203
 204 /* Store our register values back into the inferior.
 205    If REGNO is -1, do this for all registers.
 206    Otherwise, REGNO specifies which register (so we can save time).  */
 207
 208 void
 209 store_inferior_registers (int regno)
 210 {
 211   struct regs inferior_registers;
 212   struct fp_state inferior_fp_registers;
 213
 214   memcpy (&inferior_registers, registers, 20 * 4);
 215
 216   memcpy (inferior_fp_registers.f_st,
 217           &registers[REGISTER_BYTE (FP0_REGNUM)],
 218           sizeof inferior_fp_registers.f_st);
 219   memcpy (&inferior_fp_registers.f_ctrl,
 220           &registers[REGISTER_BYTE (FPC_REGNUM)],
 221           sizeof inferior_fp_registers - sizeof inferior_fp_registers.f_st);
 222
 223 #ifdef PTRACE_FP_BUG
 224   if (regno == FP_REGNUM || regno == -1)
 225     /* Storing the frame pointer requires a gross hack, in which an
 226        instruction that moves eax into ebp gets single-stepped.  */
 227     {
 228       int stack = inferior_registers.r_reg[SP_REGNUM];
 229       int stuff = ptrace (PTRACE_PEEKDATA, inferior_pid,
 230                           (PTRACE_ARG3_TYPE) stack);
 231       int reg = inferior_registers.r_reg[EAX];
 232       inferior_registers.r_reg[EAX] =
 233         inferior_registers.r_reg[FP_REGNUM];
 234       ptrace (PTRACE_SETREGS, inferior_pid,
 235               (PTRACE_ARG3_TYPE) & inferior_registers);
 236       ptrace (PTRACE_POKEDATA, inferior_pid, (PTRACE_ARG3_TYPE) stack,
 237               0xc589);
 238       ptrace (PTRACE_SINGLESTEP, inferior_pid, (PTRACE_ARG3_TYPE) stack,
 239               0);
 240       wait (0);
 241       ptrace (PTRACE_POKEDATA, inferior_pid, (PTRACE_ARG3_TYPE) stack,
 242               stuff);
 243       inferior_registers.r_reg[EAX] = reg;
 244     }
 245 #endif
 246   ptrace (PTRACE_SETREGS, inferior_pid,
 247           (PTRACE_ARG3_TYPE) & inferior_registers);
 248   ptrace (PTRACE_SETFPREGS, inferior_pid,
 249           (PTRACE_ARG3_TYPE) & inferior_fp_registers);
 250 }