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., 675 Mass Ave, Cambridge, MA 02139, USA.  */
  21
  22 #if defined (GDB_TARGET_IS_SUN386)
  23
  24 #include "defs.h"
  25 #include "frame.h"
  26 #include "inferior.h"
  27 #include "gdbcore.h"
  28
  29 #include <sys/param.h>
  30 #include <sys/dir.h>
  31 #include <sys/user.h>
  32 #include <signal.h>
  33 #include <sys/ioctl.h>
  34 #include <fcntl.h>
  35
  36 #include <sys/ptrace.h>
  37 #include <machine/reg.h>
  38
  39 #include <sys/file.h>
  40 #include <sys/stat.h>
  41 #include <sys/core.h>
  42
  43 \f
  44 /* Machine-dependent code which would otherwise be in core.c */
  45 /* Work with core files, for GDB. */
  46
  47 \f
  48 void
  49 core_file_command (filename, from_tty)
  50      char *filename;
  51      int from_tty;
  52 {
  53   int val;
  54   extern char registers[];
  55
  56   /* Discard all vestiges of any previous core file
  57      and mark data and stack spaces as empty.  */
  58
  59   if (corefile)
  60     free (corefile);
  61   corefile = 0;
  62
  63   if (corechan >= 0)
  64     close (corechan);
  65   corechan = -1;
  66
  67   data_start = 0;
  68   data_end = 0;
  69   stack_start = STACK_END_ADDR;
  70   stack_end = STACK_END_ADDR;
  71
  72   /* Now, if a new core file was specified, open it and digest it.  */
  73
  74   if (filename)
  75     {
  76       filename = tilde_expand (filename);
  77       make_cleanup (free, filename);
  78
  79       if (have_inferior_p ())
  80         error ("To look at a core file, you must kill the program with \"kill\".");
  81       corechan = open (filename, O_RDONLY, 0);
  82       if (corechan < 0)
  83         perror_with_name (filename);
  84
  85       {
  86         struct core corestr;
  87
  88         val = myread (corechan, &corestr, sizeof corestr);
  89         if (val < 0)
  90           perror_with_name (filename);
  91         if (corestr.c_magic != CORE_MAGIC)
  92           error ("\"%s\" does not appear to be a core dump file (magic 0x%x, expected 0x%x)",
  93                  filename, corestr.c_magic, (int) CORE_MAGIC);
  94         else if (sizeof (struct core) != corestr.c_len)
  95           error ("\"%s\" has an invalid struct core length (%d, expected %d)",
  96                  filename, corestr.c_len, (int) sizeof (struct core));
  97
  98         data_start = exec_data_start;
  99         data_end = data_start + corestr.c_dsize;
 100         stack_start = stack_end - corestr.c_ssize;
 101         data_offset = sizeof corestr;
 102         stack_offset = sizeof corestr + corestr.c_dsize;
 103
 104         memcpy (registers, &corestr.c_regs, sizeof corestr.c_regs);
 105
 106         memcpy (&registers[REGISTER_BYTE (FP0_REGNUM)],
 107                corestr.c_fpu.f_fpstatus.f_st,
 108                sizeof corestr.c_fpu.f_fpstatus.f_st);
 109         memcpy (&registers[REGISTER_BYTE (FPC_REGNUM)],
 110                &corestr.c_fpu.f_fpstatus.f_ctrl,
 111                sizeof corestr.c_fpu.f_fpstatus -
 112                sizeof corestr.c_fpu.f_fpstatus.f_st);
 113
 114         /* the struct aouthdr of sun coff is not the struct exec stored
 115            in the core file. */
 116         memcpy (&core_aouthdr, &corestr.c_aouthdr, sizeof (struct exec));
 117 #ifndef COFF_ENCAPSULATE
 118         core_aouthdr.magic = corestr.c_aouthdr.a_info;
 119         core_aouthdr.vstamp = /*SUNVERSION*/ 31252;
 120 #endif
 121         printf_unfiltered ("Core file is from \"%s\".\n", corestr.c_cmdname);
 122         if (corestr.c_signo > 0)
 123           printf_unfiltered ("Program terminated with signal %d, %s.\n",
 124                   corestr.c_signo, safe_strsignal (corestr.c_signo));
 125       }
 126       if (filename[0] == '/')
 127         corefile = savestring (filename, strlen (filename));
 128       else
 129         {
 130           corefile = concat (current_directory, "/", filename, NULL);
 131         }
 132
 133       set_current_frame ( create_new_frame (read_register (FP_REGNUM),
 134                                             read_pc ()));
 135       select_frame (get_current_frame (), 0);
 136
 137       validate_files ();
 138     }
 139   else if (from_tty)
 140     printf_unfiltered ("No core file now.\n");
 141 }
 142
 143 i387_to_double (from, to)
 144      char *from;
 145      char *to;
 146 {
 147   long *lp;
 148   /* push extended mode on 387 stack, then pop in double mode
 149    *
 150    * first, set exception masks so no error is generated -
 151    * number will be rounded to inf or 0, if necessary
 152    */
 153   asm ("pushl %eax");           /* grab a stack slot */
 154   asm ("fstcw (%esp)");         /* get 387 control word */
 155   asm ("movl (%esp),%eax");     /* save old value */
 156   asm ("orl $0x3f,%eax");               /* mask all exceptions */
 157   asm ("pushl %eax");
 158   asm ("fldcw (%esp)");         /* load new value into 387 */
 159
 160   asm ("movl 8(%ebp),%eax");
 161   asm ("fldt (%eax)");          /* push extended number on 387 stack */
 162   asm ("fwait");
 163   asm ("movl 12(%ebp),%eax");
 164   asm ("fstpl (%eax)");         /* pop double */
 165   asm ("fwait");
 166
 167   asm ("popl %eax");            /* flush modified control word */
 168   asm ("fnclex");                       /* clear exceptions */
 169   asm ("fldcw (%esp)");         /* restore original control word */
 170   asm ("popl %eax");            /* flush saved copy */
 171 }
 172
 173 double_to_i387 (from, to)
 174      char *from;
 175      char *to;
 176 {
 177   /* push double mode on 387 stack, then pop in extended mode
 178    * no errors are possible because every 64-bit pattern
 179    * can be converted to an extended
 180    */
 181   asm ("movl 8(%ebp),%eax");
 182   asm ("fldl (%eax)");
 183   asm ("fwait");
 184   asm ("movl 12(%ebp),%eax");
 185   asm ("fstpt (%eax)");
 186   asm ("fwait");
 187 }
 188 #else /* Not sun386 target.  */
 189
 190 /* These functions shouldn't be called when we're cross-debugging.  */
 191
 192 /* ARGSUSED */
 193 void
 194 fetch_core_registers (core_reg_sect, core_reg_size, which, reg_addr)
 195      char *core_reg_sect;
 196      unsigned core_reg_size;
 197      int which;
 198      unsigned int reg_addr;     /* Unused in this version */
 199 {
 200 }
 201
 202 #endif /* Not sun386 target.  */
 203
 204 void
 205 fetch_inferior_registers (regno)
 206      int regno;
 207 {
 208   struct regs inferior_registers;
 209   struct fp_state inferior_fp_registers;
 210   extern char registers[];
 211
 212   registers_fetched ();
 213
 214   ptrace (PTRACE_GETREGS, inferior_pid,
 215           (PTRACE_ARG3_TYPE) &inferior_registers);
 216   ptrace (PTRACE_GETFPREGS, inferior_pid,
 217           (PTRACE_ARG3_TYPE) &inferior_fp_registers);
 218
 219   memcpy (registers, &inferior_registers, sizeof inferior_registers);
 220
 221   memcpy (&registers[REGISTER_BYTE (FP0_REGNUM)],inferior_fp_registers.f_st,
 222          sizeof inferior_fp_registers.f_st);
 223   memcpy (&registers[REGISTER_BYTE (FPC_REGNUM)],
 224          &inferior_fp_registers.f_ctrl,
 225          sizeof inferior_fp_registers - sizeof inferior_fp_registers.f_st);
 226 }
 227
 228 /* Store our register values back into the inferior.
 229    If REGNO is -1, do this for all registers.
 230    Otherwise, REGNO specifies which register (so we can save time).  */
 231
 232 void
 233 store_inferior_registers (regno)
 234      int regno;
 235 {
 236   struct regs inferior_registers;
 237   struct fp_state inferior_fp_registers;
 238   extern char registers[];
 239
 240   memcpy (&inferior_registers, registers, 20 * 4);
 241
 242   memcpy (inferior_fp_registers.f_st,
 243          &registers[REGISTER_BYTE (FP0_REGNUM)],
 244          sizeof inferior_fp_registers.f_st);
 245   memcpy (&inferior_fp_registers.f_ctrl,
 246          &registers[REGISTER_BYTE (FPC_REGNUM)],
 247          sizeof inferior_fp_registers - sizeof inferior_fp_registers.f_st);
 248
 249 #ifdef PTRACE_FP_BUG
 250   if (regno == FP_REGNUM || regno == -1)
 251     /* Storing the frame pointer requires a gross hack, in which an
 252        instruction that moves eax into ebp gets single-stepped.  */
 253     {
 254       int stack = inferior_registers.r_reg[SP_REGNUM];
 255       int stuff = ptrace (PTRACE_PEEKDATA, inferior_pid,
 256                           (PTRACE_ARG3_TYPE) stack);
 257       int reg = inferior_registers.r_reg[EAX];
 258       inferior_registers.r_reg[EAX] =
 259         inferior_registers.r_reg[FP_REGNUM];
 260       ptrace (PTRACE_SETREGS, inferior_pid,
 261               (PTRACE_ARG3_TYPE) &inferior_registers);
 262       ptrace (PTRACE_POKEDATA, inferior_pid, (PTRACE_ARG3_TYPE) stack,
 263               0xc589);
 264       ptrace (PTRACE_SINGLESTEP, inferior_pid, (PTRACE_ARG3_TYPE) stack,
 265               0);
 266       wait (0);
 267       ptrace (PTRACE_POKEDATA, inferior_pid, (PTRACE_ARG3_TYPE) stack,
 268               stuff);
 269       inferior_registers.r_reg[EAX] = reg;
 270     }
 271 #endif
 272   ptrace (PTRACE_SETREGS, inferior_pid,
 273           (PTRACE_ARG3_TYPE) &inferior_registers);
 274   ptrace (PTRACE_SETFPREGS, inferior_pid,
 275           (PTRACE_ARG3_TYPE) &inferior_fp_registers);
 276 }
 277