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, Boston, MA 02111-1307, USA.  */
  21
  22 #include "defs.h"
  23 #include "frame.h"
  24 #include "inferior.h"
  25 #include "gdbcore.h"
  26
  27 #include <sys/param.h>
  28 #include <sys/dir.h>
  29 #include <sys/user.h>
  30 #include <signal.h>
  31 #include <sys/ioctl.h>
  32 #include <fcntl.h>
  33
  34 #include <sys/ptrace.h>
  35 #include <machine/reg.h>
  36
  37 #include <sys/file.h>
  38 #include "gdb_stat.h"
  39 #include <sys/core.h>
  40
  41 \f
  42 /* Machine-dependent code which would otherwise be in corefile.c */
  43 /* Work with core files, for GDB. */
  44
  45 \f
  46 void
  47 core_file_command (filename, from_tty)
  48      char *filename;
  49      int from_tty;
  50 {
  51   int val;
  52   extern char registers[];
  53
  54   /* Discard all vestiges of any previous core file
  55      and mark data and stack spaces as empty.  */
  56
  57   if (corefile)
  58     free (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 (free, 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 (from, to)
 141      char *from;
 142      char *to;
 143 {
 144   long *lp;
 145   /* push extended mode on 387 stack, then pop in double mode
 146    *
 147    * first, set exception masks so no error is generated -
 148    * number will be rounded to inf or 0, if necessary
 149    */
 150   asm ("pushl %eax");           /* grab a stack slot */
 151   asm ("fstcw (%esp)");         /* get 387 control word */
 152   asm ("movl (%esp),%eax");     /* save old value */
 153   asm ("orl $0x3f,%eax");               /* mask all exceptions */
 154   asm ("pushl %eax");
 155   asm ("fldcw (%esp)");         /* load new value into 387 */
 156
 157   asm ("movl 8(%ebp),%eax");
 158   asm ("fldt (%eax)");          /* push extended number on 387 stack */
 159   asm ("fwait");
 160   asm ("movl 12(%ebp),%eax");
 161   asm ("fstpl (%eax)");         /* pop double */
 162   asm ("fwait");
 163
 164   asm ("popl %eax");            /* flush modified control word */
 165   asm ("fnclex");                       /* clear exceptions */
 166   asm ("fldcw (%esp)");         /* restore original control word */
 167   asm ("popl %eax");            /* flush saved copy */
 168 }
 169
 170 double_to_i387 (from, to)
 171      char *from;
 172      char *to;
 173 {
 174   /* push double mode on 387 stack, then pop in extended mode
 175    * no errors are possible because every 64-bit pattern
 176    * can be converted to an extended
 177    */
 178   asm ("movl 8(%ebp),%eax");
 179   asm ("fldl (%eax)");
 180   asm ("fwait");
 181   asm ("movl 12(%ebp),%eax");
 182   asm ("fstpt (%eax)");
 183   asm ("fwait");
 184 }
 185
 186 void
 187 fetch_inferior_registers (regno)
 188      int regno;
 189 {
 190   struct regs inferior_registers;
 191   struct fp_state inferior_fp_registers;
 192   extern char registers[];
 193
 194   registers_fetched ();
 195
 196   ptrace (PTRACE_GETREGS, inferior_pid,
 197           (PTRACE_ARG3_TYPE) &inferior_registers);
 198   ptrace (PTRACE_GETFPREGS, inferior_pid,
 199           (PTRACE_ARG3_TYPE) &inferior_fp_registers);
 200
 201   memcpy (registers, &inferior_registers, sizeof inferior_registers);
 202
 203   memcpy (&registers[REGISTER_BYTE (FP0_REGNUM)],inferior_fp_registers.f_st,
 204          sizeof inferior_fp_registers.f_st);
 205   memcpy (&registers[REGISTER_BYTE (FPC_REGNUM)],
 206          &inferior_fp_registers.f_ctrl,
 207          sizeof inferior_fp_registers - sizeof inferior_fp_registers.f_st);
 208 }
 209
 210 /* Store our register values back into the inferior.
 211    If REGNO is -1, do this for all registers.
 212    Otherwise, REGNO specifies which register (so we can save time).  */
 213
 214 void
 215 store_inferior_registers (regno)
 216      int regno;
 217 {
 218   struct regs inferior_registers;
 219   struct fp_state inferior_fp_registers;
 220   extern char registers[];
 221
 222   memcpy (&inferior_registers, registers, 20 * 4);
 223
 224   memcpy (inferior_fp_registers.f_st,
 225          &registers[REGISTER_BYTE (FP0_REGNUM)],
 226          sizeof inferior_fp_registers.f_st);
 227   memcpy (&inferior_fp_registers.f_ctrl,
 228          &registers[REGISTER_BYTE (FPC_REGNUM)],
 229          sizeof inferior_fp_registers - sizeof inferior_fp_registers.f_st);
 230
 231 #ifdef PTRACE_FP_BUG
 232   if (regno == FP_REGNUM || regno == -1)
 233     /* Storing the frame pointer requires a gross hack, in which an
 234        instruction that moves eax into ebp gets single-stepped.  */
 235     {
 236       int stack = inferior_registers.r_reg[SP_REGNUM];
 237       int stuff = ptrace (PTRACE_PEEKDATA, inferior_pid,
 238                           (PTRACE_ARG3_TYPE) stack);
 239       int reg = inferior_registers.r_reg[EAX];
 240       inferior_registers.r_reg[EAX] =
 241         inferior_registers.r_reg[FP_REGNUM];
 242       ptrace (PTRACE_SETREGS, inferior_pid,
 243               (PTRACE_ARG3_TYPE) &inferior_registers);
 244       ptrace (PTRACE_POKEDATA, inferior_pid, (PTRACE_ARG3_TYPE) stack,
 245               0xc589);
 246       ptrace (PTRACE_SINGLESTEP, inferior_pid, (PTRACE_ARG3_TYPE) stack,
 247               0);
 248       wait (0);
 249       ptrace (PTRACE_POKEDATA, inferior_pid, (PTRACE_ARG3_TYPE) stack,
 250               stuff);
 251       inferior_registers.r_reg[EAX] = reg;
 252     }
 253 #endif
 254   ptrace (PTRACE_SETREGS, inferior_pid,
 255           (PTRACE_ARG3_TYPE) &inferior_registers);
 256   ptrace (PTRACE_SETFPREGS, inferior_pid,
 257           (PTRACE_ARG3_TYPE) &inferior_fp_registers);
 258 }