gdb/sun386-xdep.c

   1 /* Machine-dependent code for host Sun 386i's for GDB, the GNU debugger.
   2    Copyright (C) 1986, 1987, 1989, 1991 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 <stdio.h>
  25 #include "defs.h"
  26 #include "frame.h"
  27 #include "inferior.h"
  28 #include "signame.h"
  29 #include "gdbcore.h"
  30
  31 #include <sys/param.h>
  32 #include <sys/dir.h>
  33 #include <sys/user.h>
  34 #include <signal.h>
  35 #include <sys/ioctl.h>
  36 #include <fcntl.h>
  37
  38 #include <sys/ptrace.h>
  39 #include <machine/reg.h>
  40
  41 #include <sys/file.h>
  42 #include <sys/stat.h>
  43 #include <sys/core.h>
  44 \f
  45 void
  46 fetch_inferior_registers ()
  47 {
  48   struct regs inferior_registers;
  49   struct fp_state inferior_fp_registers;
  50   extern char registers[];
  51
  52   registers_fetched ();
  53
  54   ptrace (PTRACE_GETREGS, inferior_pid, &inferior_registers);
  55   ptrace (PTRACE_GETFPREGS, inferior_pid, &inferior_fp_registers);
  56
  57   bcopy (&inferior_registers, registers, sizeof inferior_registers);
  58
  59   bcopy (inferior_fp_registers.f_st,&registers[REGISTER_BYTE (FP0_REGNUM)],
  60          sizeof inferior_fp_registers.f_st);
  61   bcopy (&inferior_fp_registers.f_ctrl,
  62          &registers[REGISTER_BYTE (FPC_REGNUM)],
  63          sizeof inferior_fp_registers - sizeof inferior_fp_registers.f_st);
  64 }
  65
  66 /* Store our register values back into the inferior.
  67    If REGNO is -1, do this for all registers.
  68    Otherwise, REGNO specifies which register (so we can save time).  */
  69
  70 store_inferior_registers (regno)
  71      int regno;
  72 {
  73   struct regs inferior_registers;
  74   struct fp_state inferior_fp_registers;
  75   extern char registers[];
  76
  77   bcopy (registers, &inferior_registers, 20 * 4);
  78
  79   bcopy (&registers[REGISTER_BYTE (FP0_REGNUM)],inferior_fp_registers.f_st,
  80          sizeof inferior_fp_registers.f_st);
  81   bcopy (&registers[REGISTER_BYTE (FPC_REGNUM)],
  82          &inferior_fp_registers.f_ctrl,
  83          sizeof inferior_fp_registers - sizeof inferior_fp_registers.f_st);
  84
  85 #ifdef PTRACE_FP_BUG
  86   if (regno == FP_REGNUM || regno == -1)
  87     /* Storing the frame pointer requires a gross hack, in which an
  88        instruction that moves eax into ebp gets single-stepped.  */
  89     {
  90       int stack = inferior_registers.r_reg[SP_REGNUM];
  91       int stuff = ptrace (PTRACE_PEEKDATA, inferior_pid, stack);
  92       int reg = inferior_registers.r_reg[EAX];
  93       inferior_registers.r_reg[EAX] =
  94         inferior_registers.r_reg[FP_REGNUM];
  95       ptrace (PTRACE_SETREGS, inferior_pid, &inferior_registers);
  96       ptrace (PTRACE_POKEDATA, inferior_pid, stack, 0xc589);
  97       ptrace (PTRACE_SINGLESTEP, inferior_pid, stack, 0);
  98       wait (0);
  99       ptrace (PTRACE_POKEDATA, inferior_pid, stack, stuff);
 100       inferior_registers.r_reg[EAX] = reg;
 101     }
 102 #endif
 103   ptrace (PTRACE_SETREGS, inferior_pid, &inferior_registers);
 104   ptrace (PTRACE_SETFPREGS, inferior_pid, &inferior_fp_registers);
 105 }
 106
 107 /* Machine-dependent code which would otherwise be in core.c */
 108 /* Work with core files, for GDB. */
 109
 110 \f
 111 void
 112 core_file_command (filename, from_tty)
 113      char *filename;
 114      int from_tty;
 115 {
 116   int val;
 117   extern char registers[];
 118
 119   /* Discard all vestiges of any previous core file
 120      and mark data and stack spaces as empty.  */
 121
 122   if (corefile)
 123     free (corefile);
 124   corefile = 0;
 125
 126   if (corechan >= 0)
 127     close (corechan);
 128   corechan = -1;
 129
 130   data_start = 0;
 131   data_end = 0;
 132   stack_start = STACK_END_ADDR;
 133   stack_end = STACK_END_ADDR;
 134
 135   /* Now, if a new core file was specified, open it and digest it.  */
 136
 137   if (filename)
 138     {
 139       filename = tilde_expand (filename);
 140       make_cleanup (free, filename);
 141
 142       if (have_inferior_p ())
 143         error ("To look at a core file, you must kill the inferior with \"kill\".");
 144       corechan = open (filename, O_RDONLY, 0);
 145       if (corechan < 0)
 146         perror_with_name (filename);
 147
 148       {
 149         struct core corestr;
 150
 151         val = myread (corechan, &corestr, sizeof corestr);
 152         if (val < 0)
 153           perror_with_name (filename);
 154         if (corestr.c_magic != CORE_MAGIC)
 155           error ("\"%s\" does not appear to be a core dump file (magic 0x%x, expected 0x%x)",
 156                  filename, corestr.c_magic, (int) CORE_MAGIC);
 157         else if (sizeof (struct core) != corestr.c_len)
 158           error ("\"%s\" has an invalid struct core length (%d, expected %d)",
 159                  filename, corestr.c_len, (int) sizeof (struct core));
 160
 161         data_start = exec_data_start;
 162         data_end = data_start + corestr.c_dsize;
 163         stack_start = stack_end - corestr.c_ssize;
 164         data_offset = sizeof corestr;
 165         stack_offset = sizeof corestr + corestr.c_dsize;
 166
 167         bcopy (&corestr.c_regs, registers, sizeof corestr.c_regs);
 168
 169         bcopy (corestr.c_fpu.f_fpstatus.f_st,
 170                &registers[REGISTER_BYTE (FP0_REGNUM)],
 171                sizeof corestr.c_fpu.f_fpstatus.f_st);
 172         bcopy (&corestr.c_fpu.f_fpstatus.f_ctrl,
 173                &registers[REGISTER_BYTE (FPC_REGNUM)],
 174                sizeof corestr.c_fpu.f_fpstatus -
 175                sizeof corestr.c_fpu.f_fpstatus.f_st);
 176
 177         /* the struct aouthdr of sun coff is not the struct exec stored
 178            in the core file. */
 179         bcopy (&corestr.c_aouthdr, &core_aouthdr, sizeof (struct exec));
 180 #ifndef COFF_ENCAPSULATE
 181         core_aouthdr.magic = corestr.c_aouthdr.a_info;
 182         core_aouthdr.vstamp = /*SUNVERSION*/ 31252;
 183 #endif
 184         printf ("Core file is from \"%s\".\n", corestr.c_cmdname);
 185         if (corestr.c_signo > 0)
 186           printf ("Program terminated with signal %d, %s.\n",
 187                         corestr.c_signo,
 188                         corestr.c_signo < NSIG
 189                         ? sys_siglist[corestr.c_signo]
 190                         : "(undocumented)");
 191       }
 192       if (filename[0] == '/')
 193         corefile = savestring (filename, strlen (filename));
 194       else
 195         {
 196           corefile = concat (current_directory, "/", filename, NULL);
 197         }
 198
 199       set_current_frame ( create_new_frame (read_register (FP_REGNUM),
 200                                             read_pc ()));
 201       select_frame (get_current_frame (), 0);
 202
 203       validate_files ();
 204     }
 205   else if (from_tty)
 206     printf ("No core file now.\n");
 207 }
 208
 209 i387_to_double (from, to)
 210      char *from;
 211      char *to;
 212 {
 213   long *lp;
 214   /* push extended mode on 387 stack, then pop in double mode
 215    *
 216    * first, set exception masks so no error is generated -
 217    * number will be rounded to inf or 0, if necessary
 218    */
 219   asm ("pushl %eax");           /* grab a stack slot */
 220   asm ("fstcw (%esp)");         /* get 387 control word */
 221   asm ("movl (%esp),%eax");     /* save old value */
 222   asm ("orl $0x3f,%eax");               /* mask all exceptions */
 223   asm ("pushl %eax");
 224   asm ("fldcw (%esp)");         /* load new value into 387 */
 225
 226   asm ("movl 8(%ebp),%eax");
 227   asm ("fldt (%eax)");          /* push extended number on 387 stack */
 228   asm ("fwait");
 229   asm ("movl 12(%ebp),%eax");
 230   asm ("fstpl (%eax)");         /* pop double */
 231   asm ("fwait");
 232
 233   asm ("popl %eax");            /* flush modified control word */
 234   asm ("fnclex");                       /* clear exceptions */
 235   asm ("fldcw (%esp)");         /* restore original control word */
 236   asm ("popl %eax");            /* flush saved copy */
 237 }
 238
 239 double_to_i387 (from, to)
 240      char *from;
 241      char *to;
 242 {
 243   /* push double mode on 387 stack, then pop in extended mode
 244    * no errors are possible because every 64-bit pattern
 245    * can be converted to an extended
 246    */
 247   asm ("movl 8(%ebp),%eax");
 248   asm ("fldl (%eax)");
 249   asm ("fwait");
 250   asm ("movl 12(%ebp),%eax");
 251   asm ("fstpt (%eax)");
 252   asm ("fwait");
 253 }
 254 #else /* Not sun386 target.  */
 255
 256 /* These functions shouldn't be called when we're cross-debugging.  */
 257
 258 void
 259 fetch_inferior_registers ()
 260 {
 261 }
 262
 263 /* ARGSUSED */
 264 store_inferior_registers (regno)
 265      int regno;
 266 {
 267 }
 268
 269 /* ARGSUSED */
 270 void
 271 fetch_core_registers (core_reg_sect, core_reg_size, which)
 272      char *core_reg_sect;
 273      unsigned core_reg_size;
 274      int which;
 275 {
 276 }
 277
 278 #endif /* Not sun386 target.  */