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