gdb/sun386-nat.c

   1 /* Native support for Sun 386i's for GDB, the GNU debugger.
   2    Copyright (C) 1986, 1987, 1989, 1991, 1992 Free Software Foundation, Inc.
   3    Changes for sun386i by Jean Daniel Fekete (jdf@litp.univ-p6-7.fr),
   4    C2V Paris, April 89.
   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 "frame.h"
  25 #include "inferior.h"
  26 #include "gdbcore.h"
  27
  28 #include <sys/param.h>
  29 #include <sys/dir.h>
  30 #include <sys/user.h>
  31 #include <signal.h>
  32 #include <sys/ioctl.h>
  33 #include <fcntl.h>
  34
  35 #include <sys/ptrace.h>
  36 #include <machine/reg.h>
  37
  38 #include <sys/file.h>
  39 #include "gdb_stat.h"
  40 #include <sys/core.h>
  41 \f
  42
  43 /* Machine-dependent code which would otherwise be in corefile.c */
  44 /* Work with core files, for GDB. */
  45 \f
  46
  47 void
  48 core_file_command (char *filename, int from_tty)
  49 {
  50   int val;
  51
  52   /* Discard all vestiges of any previous core file
  53      and mark data and stack spaces as empty.  */
  54
  55   if (corefile)
  56     free (corefile);
  57   corefile = 0;
  58
  59   if (corechan >= 0)
  60     close (corechan);
  61   corechan = -1;
  62
  63   data_start = 0;
  64   data_end = 0;
  65   stack_start = STACK_END_ADDR;
  66   stack_end = STACK_END_ADDR;
  67
  68   /* Now, if a new core file was specified, open it and digest it.  */
  69
  70   if (filename)
  71     {
  72       filename = tilde_expand (filename);
  73       make_cleanup (free, filename);
  74
  75       if (have_inferior_p ())
  76         error ("To look at a core file, you must kill the program with \"kill\".");
  77       corechan = open (filename, O_RDONLY, 0);
  78       if (corechan < 0)
  79         perror_with_name (filename);
  80
  81       {
  82         struct core corestr;
  83
  84         val = myread (corechan, &corestr, sizeof corestr);
  85         if (val < 0)
  86           perror_with_name (filename);
  87         if (corestr.c_magic != CORE_MAGIC)
  88           error ("\"%s\" does not appear to be a core dump file (magic 0x%x, expected 0x%x)",
  89                  filename, corestr.c_magic, (int) CORE_MAGIC);
  90         else if (sizeof (struct core) != corestr.c_len)
  91             error ("\"%s\" has an invalid struct core length (%d, expected %d)",
  92                    filename, corestr.c_len, (int) sizeof (struct core));
  93
  94         data_start = exec_data_start;
  95         data_end = data_start + corestr.c_dsize;
  96         stack_start = stack_end - corestr.c_ssize;
  97         data_offset = sizeof corestr;
  98         stack_offset = sizeof corestr + corestr.c_dsize;
  99
 100         memcpy (registers, &corestr.c_regs, sizeof corestr.c_regs);
 101
 102         memcpy (&registers[REGISTER_BYTE (FP0_REGNUM)],
 103                 corestr.c_fpu.f_fpstatus.f_st,
 104                 sizeof corestr.c_fpu.f_fpstatus.f_st);
 105         memcpy (&registers[REGISTER_BYTE (FPC_REGNUM)],
 106                 &corestr.c_fpu.f_fpstatus.f_ctrl,
 107                 sizeof corestr.c_fpu.f_fpstatus -
 108                 sizeof corestr.c_fpu.f_fpstatus.f_st);
 109
 110         /* the struct aouthdr of sun coff is not the struct exec stored
 111            in the core file. */
 112         memcpy (&core_aouthdr, &corestr.c_aouthdr, sizeof (struct exec));
 113 #ifndef COFF_ENCAPSULATE
 114         core_aouthdr.magic = corestr.c_aouthdr.a_info;
 115         core_aouthdr.vstamp = /*SUNVERSION */ 31252;
 116 #endif
 117         printf_unfiltered ("Core file is from \"%s\".\n", corestr.c_cmdname);
 118         if (corestr.c_signo > 0)
 119           printf_unfiltered ("Program terminated with signal %d, %s.\n",
 120                          corestr.c_signo, safe_strsignal (corestr.c_signo));
 121       }
 122       if (filename[0] == '/')
 123         corefile = savestring (filename, strlen (filename));
 124       else
 125         {
 126           corefile = concat (current_directory, "/", filename, NULL);
 127         }
 128
 129       flush_cached_frames ();
 130       select_frame (get_current_frame (), 0);
 131
 132       validate_files ();
 133     }
 134   else if (from_tty)
 135     printf_unfiltered ("No core file now.\n");
 136 }
 137
 138 i387_to_double (char *from, char *to)
 139 {
 140   long *lp;
 141   /* push extended mode on 387 stack, then pop in double mode
 142
 143    * first, set exception masks so no error is generated -
 144    * number will be rounded to inf or 0, if necessary
 145    */
 146   asm ("pushl %eax");           /* grab a stack slot */
 147   asm ("fstcw (%esp)");         /* get 387 control word */
 148   asm ("movl (%esp),%eax");     /* save old value */
 149   asm ("orl $0x3f,%eax");       /* mask all exceptions */
 150   asm ("pushl %eax");
 151   asm ("fldcw (%esp)");         /* load new value into 387 */
 152
 153   asm ("movl 8(%ebp),%eax");
 154   asm ("fldt (%eax)");          /* push extended number on 387 stack */
 155   asm ("fwait");
 156   asm ("movl 12(%ebp),%eax");
 157   asm ("fstpl (%eax)");         /* pop double */
 158   asm ("fwait");
 159
 160   asm ("popl %eax");            /* flush modified control word */
 161   asm ("fnclex");               /* clear exceptions */
 162   asm ("fldcw (%esp)");         /* restore original control word */
 163   asm ("popl %eax");            /* flush saved copy */
 164 }
 165
 166 double_to_i387 (char *from, char *to)
 167 {
 168   /* push double mode on 387 stack, then pop in extended mode
 169    * no errors are possible because every 64-bit pattern
 170    * can be converted to an extended
 171    */
 172   asm ("movl 8(%ebp),%eax");
 173   asm ("fldl (%eax)");
 174   asm ("fwait");
 175   asm ("movl 12(%ebp),%eax");
 176   asm ("fstpt (%eax)");
 177   asm ("fwait");
 178 }
 179
 180 void
 181 fetch_inferior_registers (int regno)
 182 {
 183   struct regs inferior_registers;
 184   struct fp_state inferior_fp_registers;
 185
 186   registers_fetched ();
 187
 188   ptrace (PTRACE_GETREGS, inferior_pid,
 189           (PTRACE_ARG3_TYPE) & inferior_registers);
 190   ptrace (PTRACE_GETFPREGS, inferior_pid,
 191           (PTRACE_ARG3_TYPE) & inferior_fp_registers);
 192
 193   memcpy (registers, &inferior_registers, sizeof inferior_registers);
 194
 195   memcpy (&registers[REGISTER_BYTE (FP0_REGNUM)], inferior_fp_registers.f_st,
 196           sizeof inferior_fp_registers.f_st);
 197   memcpy (&registers[REGISTER_BYTE (FPC_REGNUM)],
 198           &inferior_fp_registers.f_ctrl,
 199           sizeof inferior_fp_registers - sizeof inferior_fp_registers.f_st);
 200 }
 201
 202 /* Store our register values back into the inferior.
 203    If REGNO is -1, do this for all registers.
 204    Otherwise, REGNO specifies which register (so we can save time).  */
 205
 206 void
 207 store_inferior_registers (int regno)
 208 {
 209   struct regs inferior_registers;
 210   struct fp_state inferior_fp_registers;
 211
 212   memcpy (&inferior_registers, registers, 20 * 4);
 213
 214   memcpy (inferior_fp_registers.f_st,
 215           &registers[REGISTER_BYTE (FP0_REGNUM)],
 216           sizeof inferior_fp_registers.f_st);
 217   memcpy (&inferior_fp_registers.f_ctrl,
 218           &registers[REGISTER_BYTE (FPC_REGNUM)],
 219           sizeof inferior_fp_registers - sizeof inferior_fp_registers.f_st);
 220
 221 #ifdef PTRACE_FP_BUG
 222   if (regno == FP_REGNUM || regno == -1)
 223     /* Storing the frame pointer requires a gross hack, in which an
 224        instruction that moves eax into ebp gets single-stepped.  */
 225     {
 226       int stack = inferior_registers.r_reg[SP_REGNUM];
 227       int stuff = ptrace (PTRACE_PEEKDATA, inferior_pid,
 228                           (PTRACE_ARG3_TYPE) stack);
 229       int reg = inferior_registers.r_reg[EAX];
 230       inferior_registers.r_reg[EAX] =
 231         inferior_registers.r_reg[FP_REGNUM];
 232       ptrace (PTRACE_SETREGS, inferior_pid,
 233               (PTRACE_ARG3_TYPE) & inferior_registers);
 234       ptrace (PTRACE_POKEDATA, inferior_pid, (PTRACE_ARG3_TYPE) stack,
 235               0xc589);
 236       ptrace (PTRACE_SINGLESTEP, inferior_pid, (PTRACE_ARG3_TYPE) stack,
 237               0);
 238       wait (0);
 239       ptrace (PTRACE_POKEDATA, inferior_pid, (PTRACE_ARG3_TYPE) stack,
 240               stuff);
 241       inferior_registers.r_reg[EAX] = reg;
 242     }
 243 #endif
 244   ptrace (PTRACE_SETREGS, inferior_pid,
 245           (PTRACE_ARG3_TYPE) & inferior_registers);
 246   ptrace (PTRACE_SETFPREGS, inferior_pid,
 247           (PTRACE_ARG3_TYPE) & inferior_fp_registers);
 248 }