gdb/m68kbsd-nat.c

   1 /* Native-dependent code for Motorola 68000 BSD's.
   2
   3    Copyright (C) 2004, 2007-2012 Free Software Foundation, Inc.
   4
   5    This file is part of GDB.
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 3 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  19
  20 #include "defs.h"
  21 #include "gdbcore.h"
  22 #include "inferior.h"
  23 #include "regcache.h"
  24
  25 #include "gdb_assert.h"
  26 #include <sys/types.h>
  27 #include <sys/ptrace.h>
  28 #include <machine/reg.h>
  29
  30 #include "m68k-tdep.h"
  31 #include "inf-ptrace.h"
  32
  33 static int
  34 m68kbsd_gregset_supplies_p (int regnum)
  35 {
  36   return (regnum >= M68K_D0_REGNUM && regnum <= M68K_PC_REGNUM);
  37 }
  38
  39 static int
  40 m68kbsd_fpregset_supplies_p (int regnum)
  41 {
  42   return (regnum >= M68K_FP0_REGNUM && regnum <= M68K_FPI_REGNUM);
  43 }
  44
  45 /* Supply the general-purpose registers stored in GREGS to REGCACHE.  */
  46
  47 static void
  48 m68kbsd_supply_gregset (struct regcache *regcache, const void *gregs)
  49 {
  50   const char *regs = gregs;
  51   int regnum;
  52
  53   for (regnum = M68K_D0_REGNUM; regnum <= M68K_PC_REGNUM; regnum++)
  54     regcache_raw_supply (regcache, regnum, regs + regnum * 4);
  55 }
  56
  57 /* Supply the floating-point registers stored in FPREGS to REGCACHE.  */
  58
  59 static void
  60 m68kbsd_supply_fpregset (struct regcache *regcache, const void *fpregs)
  61 {
  62   struct gdbarch *gdbarch = get_regcache_arch (regcache);
  63   const char *regs = fpregs;
  64   int regnum;
  65
  66   for (regnum = M68K_FP0_REGNUM; regnum <= M68K_FPI_REGNUM; regnum++)
  67     regcache_raw_supply (regcache, regnum,
  68                          regs + m68kbsd_fpreg_offset (gdbarch, regnum));
  69 }
  70
  71 /* Collect the general-purpose registers from REGCACHE and store them
  72    in GREGS.  */
  73
  74 static void
  75 m68kbsd_collect_gregset (const struct regcache *regcache,
  76                          void *gregs, int regnum)
  77 {
  78   char *regs = gregs;
  79   int i;
  80
  81   for (i = M68K_D0_REGNUM; i <= M68K_PC_REGNUM; i++)
  82     {
  83       if (regnum == -1 || regnum == i)
  84         regcache_raw_collect (regcache, i, regs + i * 4);
  85     }
  86 }
  87
  88 /* Collect the floating-point registers from REGCACHE and store them
  89    in FPREGS.  */
  90
  91 static void
  92 m68kbsd_collect_fpregset (struct regcache *regcache,
  93                           void *fpregs, int regnum)
  94 {
  95   struct gdbarch *gdbarch = get_regcache_arch (regcache);
  96   char *regs = fpregs;
  97   int i;
  98
  99   for (i = M68K_FP0_REGNUM; i <= M68K_FPI_REGNUM; i++)
 100     {
 101       if (regnum == -1 || regnum == i)
 102         regcache_raw_collect (regcache, i,
 103                               regs + m68kbsd_fpreg_offset (gdbarch, i));
 104     }
 105 }
 106 \f
 107
 108 /* Fetch register REGNUM from the inferior.  If REGNUM is -1, do this
 109    for all registers (including the floating-point registers).  */
 110
 111 static void
 112 m68kbsd_fetch_inferior_registers (struct target_ops *ops,
 113                                   struct regcache *regcache, int regnum)
 114 {
 115   if (regnum == -1 || m68kbsd_gregset_supplies_p (regnum))
 116     {
 117       struct reg regs;
 118
 119       if (ptrace (PT_GETREGS, PIDGET (inferior_ptid),
 120                   (PTRACE_TYPE_ARG3) &regs, 0) == -1)
 121         perror_with_name (_("Couldn't get registers"));
 122
 123       m68kbsd_supply_gregset (regcache, &regs);
 124     }
 125
 126   if (regnum == -1 || m68kbsd_fpregset_supplies_p (regnum))
 127     {
 128       struct fpreg fpregs;
 129
 130       if (ptrace (PT_GETFPREGS, PIDGET (inferior_ptid),
 131                   (PTRACE_TYPE_ARG3) &fpregs, 0) == -1)
 132         perror_with_name (_("Couldn't get floating point status"));
 133
 134       m68kbsd_supply_fpregset (regcache, &fpregs);
 135     }
 136 }
 137
 138 /* Store register REGNUM back into the inferior.  If REGNUM is -1, do
 139    this for all registers (including the floating-point registers).  */
 140
 141 static void
 142 m68kbsd_store_inferior_registers (struct target_ops *ops,
 143                                   struct regcache *regcache, int regnum)
 144 {
 145   if (regnum == -1 || m68kbsd_gregset_supplies_p (regnum))
 146     {
 147       struct reg regs;
 148
 149       if (ptrace (PT_GETREGS, PIDGET (inferior_ptid),
 150                   (PTRACE_TYPE_ARG3) &regs, 0) == -1)
 151         perror_with_name (_("Couldn't get registers"));
 152
 153       m68kbsd_collect_gregset (regcache, &regs, regnum);
 154
 155       if (ptrace (PT_SETREGS, PIDGET (inferior_ptid),
 156                   (PTRACE_TYPE_ARG3) &regs, 0) == -1)
 157         perror_with_name (_("Couldn't write registers"));
 158     }
 159
 160   if (regnum == -1 || m68kbsd_fpregset_supplies_p (regnum))
 161     {
 162       struct fpreg fpregs;
 163
 164       if (ptrace (PT_GETFPREGS, PIDGET (inferior_ptid),
 165                   (PTRACE_TYPE_ARG3) &fpregs, 0) == -1)
 166         perror_with_name (_("Couldn't get floating point status"));
 167
 168       m68kbsd_collect_fpregset (regcache, &fpregs, regnum);
 169
 170       if (ptrace (PT_SETFPREGS, PIDGET (inferior_ptid),
 171                   (PTRACE_TYPE_ARG3) &fpregs, 0) == -1)
 172         perror_with_name (_("Couldn't write floating point status"));
 173     }
 174 }
 175 \f
 176
 177 /* Support for debugging kernel virtual memory images.  */
 178
 179 #include <sys/types.h>
 180 #include <machine/pcb.h>
 181
 182 #include "bsd-kvm.h"
 183
 184 /* OpenBSD doesn't have these.  */
 185 #ifndef PCB_REGS_FP
 186 #define PCB_REGS_FP 10
 187 #endif
 188 #ifndef PCB_REGS_SP
 189 #define PCB_REGS_SP 11
 190 #endif
 191
 192 static int
 193 m68kbsd_supply_pcb (struct regcache *regcache, struct pcb *pcb)
 194 {
 195   int regnum, tmp;
 196   int i = 0;
 197
 198   /* The following is true for NetBSD 1.6.2:
 199
 200      The pcb contains %d2...%d7, %a2...%a7 and %ps.  This accounts for
 201      all callee-saved registers.  From this information we reconstruct
 202      the register state as it would look when we just returned from
 203      cpu_switch().  */
 204
 205   /* The stack pointer shouldn't be zero.  */
 206   if (pcb->pcb_regs[PCB_REGS_SP] == 0)
 207     return 0;
 208
 209   for (regnum = M68K_D2_REGNUM; regnum <= M68K_D7_REGNUM; regnum++)
 210     regcache_raw_supply (regcache, regnum, &pcb->pcb_regs[i++]);
 211   for (regnum = M68K_A2_REGNUM; regnum <= M68K_SP_REGNUM; regnum++)
 212     regcache_raw_supply (regcache, regnum, &pcb->pcb_regs[i++]);
 213
 214   tmp = pcb->pcb_ps & 0xffff;
 215   regcache_raw_supply (regcache, M68K_PS_REGNUM, &tmp);
 216
 217   read_memory (pcb->pcb_regs[PCB_REGS_FP] + 4, (char *) &tmp, sizeof tmp);
 218   regcache_raw_supply (regcache, M68K_PC_REGNUM, &tmp);
 219
 220   return 1;
 221 }
 222 \f
 223
 224 /* Provide a prototype to silence -Wmissing-prototypes.  */
 225 void _initialize_m68kbsd_nat (void);
 226
 227 void
 228 _initialize_m68kbsd_nat (void)
 229 {
 230   struct target_ops *t;
 231
 232   t = inf_ptrace_target ();
 233   t->to_fetch_registers = m68kbsd_fetch_inferior_registers;
 234   t->to_store_registers = m68kbsd_store_inferior_registers;
 235   add_target (t);
 236
 237   /* Support debugging kernel virtual memory images.  */
 238   bsd_kvm_add_target (m68kbsd_supply_pcb);
 239 }