gdb/mach386-xdep.c

   1 /* Machine-dependent code for host Mach 386's for GDB, the GNU debugger.
   2    Copyright (C) 1986, 1987, 1989, 1991 Free Software Foundation, Inc.
   3
   4 This file is part of GDB.
   5
   6 This program is free software; you can redistribute it and/or modify
   7 it under the terms of the GNU General Public License as published by
   8 the Free Software Foundation; either version 2 of the License, or
   9 (at your option) any later version.
  10
  11 This program is distributed in the hope that it will be useful,
  12 but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 GNU General Public License for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with this program; if not, write to the Free Software
  18 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.  */
  19
  20 #include "defs.h"
  21 #include "frame.h"
  22 #include "inferior.h"
  23 #include "gdbcore.h"
  24
  25 #if defined (GDB_TARGET_IS_MACH386)
  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 <sys/stat.h>
  39 #include <sys/core.h>
  40
  41 \f
  42 void
  43 fetch_inferior_registers (regno)
  44      int regno;         /* Original value discarded */
  45 {
  46   struct regs inferior_registers;
  47   struct fp_state inferior_fp_registers;
  48   extern char registers[];
  49
  50   registers_fetched ();
  51
  52   ptrace (PTRACE_GETREGS, inferior_pid,
  53           (PTRACE_ARG3_TYPE) &inferior_registers);
  54   ptrace (PTRACE_GETFPREGS, inferior_pid,
  55           (PTRACE_ARG3_TYPE) &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 void
  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,
  93                           (PTRACE_ARG3_TYPE) stack);
  94       int reg = inferior_registers.r_reg[EAX];
  95       inferior_registers.r_reg[EAX] =
  96         inferior_registers.r_reg[FP_REGNUM];
  97       ptrace (PTRACE_SETREGS, inferior_pid,
  98               (PTRACE_ARG3_TYPE) &inferior_registers);
  99       ptrace (PTRACE_POKEDATA, inferior_pid, (PTRACE_ARG3_TYPE) stack, 0xc589);
 100       ptrace (PTRACE_SINGLESTEP, inferior_pid, (PTRACE_ARG3_TYPE) stack, 0);
 101       wait (0);
 102       ptrace (PTRACE_POKEDATA, inferior_pid, (PTRACE_ARG3_TYPE) stack, stuff);
 103       inferior_registers.r_reg[EAX] = reg;
 104     }
 105 #endif
 106   ptrace (PTRACE_SETREGS, inferior_pid,
 107           (PTRACE_ARG3_TYPE) &inferior_registers);
 108   ptrace (PTRACE_SETFPREGS, inferior_pid,
 109           (PTRACE_ARG3_TYPE) &inferior_fp_registers);
 110 }
 111
 112 #else /* Not mach386 target.  */
 113
 114 /* These functions shouldn't be called when we're cross-debugging.  */
 115
 116 /* ARGSUSED */
 117 void
 118 fetch_inferior_registers (regno)
 119      int regno;
 120 {
 121 }
 122
 123 /* ARGSUSED */
 124 void
 125 store_inferior_registers (regno)
 126      int regno;
 127 {
 128 }
 129
 130 #endif /* Not mach386 target.  */
 131
 132 /* Work with core files, for GDB. */
 133
 134 void
 135 fetch_core_registers (core_reg_sect, core_reg_size, which, reg_addr)
 136      char *core_reg_sect;
 137      unsigned core_reg_size;
 138      int which;
 139      unsigned int reg_addr;     /* Unused in this version */
 140 {
 141   int val;
 142   extern char registers[];
 143
 144   switch (which) {
 145   case 0:
 146   case 1:
 147     bcopy (core_reg_sect, registers, core_reg_size);
 148     break;
 149
 150   case 2:
 151 #ifdef FP0_REGNUM
 152     bcopy (core_reg_sect,
 153            &registers[REGISTER_BYTE (FP0_REGNUM)],
 154            core_reg_size);              /* FIXME, probably bogus */
 155 #endif
 156 #ifdef FPC_REGNUM
 157     bcopy (&corestr.c_fpu.f_fpstatus.f_ctrl,
 158            &registers[REGISTER_BYTE (FPC_REGNUM)],
 159            sizeof corestr.c_fpu.f_fpstatus -
 160            sizeof corestr.c_fpu.f_fpstatus.f_st);
 161 #endif
 162     break;
 163   }
 164 }