gdb/m68kbsd-nat.c

   1 /* Native-dependent code for Motorola 68000 BSD's.
   2
   3    Copyright (C) 2004, 2007, 2008 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   const char *regs = fpregs;
  63   int regnum;
  64
  65   for (regnum = M68K_FP0_REGNUM; regnum <= M68K_FPI_REGNUM; regnum++)
  66     regcache_raw_supply (regcache, regnum,
  67                          regs + m68kbsd_fpreg_offset (regnum));
  68 }
  69
  70 /* Collect the general-purpose registers from REGCACHE and store them
  71    in GREGS.  */
  72
  73 static void
  74 m68kbsd_collect_gregset (const struct regcache *regcache,
  75                          void *gregs, int regnum)
  76 {
  77   char *regs = gregs;
  78   int i;
  79
  80   for (i = M68K_D0_REGNUM; i <= M68K_PC_REGNUM; i++)
  81     {
  82       if (regnum == -1 || regnum == i)
  83         regcache_raw_collect (regcache, i, regs + i * 4);
  84     }
  85 }
  86
  87 /* Collect the floating-point registers from REGCACHE and store them
  88    in FPREGS.  */
  89
  90 static void
  91 m68kbsd_collect_fpregset (struct regcache *regcache,
  92                           void *fpregs, int regnum)
  93 {
  94   char *regs = fpregs;
  95   int i;
  96
  97   for (i = M68K_FP0_REGNUM; i <= M68K_FPI_REGNUM; i++)
  98     {
  99       if (regnum == -1 || regnum == i)
 100         regcache_raw_collect (regcache, i, regs + m68kbsd_fpreg_offset (i));
 101     }
 102 }
 103 \f
 104
 105 /* Fetch register REGNUM from the inferior.  If REGNUM is -1, do this
 106    for all registers (including the floating-point registers).  */
 107
 108 static void
 109 m68kbsd_fetch_inferior_registers (struct regcache *regcache, int regnum)
 110 {
 111   if (regnum == -1 || m68kbsd_gregset_supplies_p (regnum))
 112     {
 113       struct reg regs;
 114
 115       if (ptrace (PT_GETREGS, PIDGET (inferior_ptid),
 116                   (PTRACE_TYPE_ARG3) &regs, 0) == -1)
 117         perror_with_name (_("Couldn't get registers"));
 118
 119       m68kbsd_supply_gregset (regcache, &regs);
 120     }
 121
 122   if (regnum == -1 || m68kbsd_fpregset_supplies_p (regnum))
 123     {
 124       struct fpreg fpregs;
 125
 126       if (ptrace (PT_GETFPREGS, PIDGET (inferior_ptid),
 127                   (PTRACE_TYPE_ARG3) &fpregs, 0) == -1)
 128         perror_with_name (_("Couldn't get floating point status"));
 129
 130       m68kbsd_supply_fpregset (regcache, &fpregs);
 131     }
 132 }
 133
 134 /* Store register REGNUM back into the inferior.  If REGNUM is -1, do
 135    this for all registers (including the floating-point registers).  */
 136
 137 static void
 138 m68kbsd_store_inferior_registers (struct regcache *regcache, int regnum)
 139 {
 140   if (regnum == -1 || m68kbsd_gregset_supplies_p (regnum))
 141     {
 142       struct reg regs;
 143
 144       if (ptrace (PT_GETREGS, PIDGET (inferior_ptid),
 145                   (PTRACE_TYPE_ARG3) &regs, 0) == -1)
 146         perror_with_name (_("Couldn't get registers"));
 147
 148       m68kbsd_collect_gregset (regcache, &regs, regnum);
 149
 150       if (ptrace (PT_SETREGS, PIDGET (inferior_ptid),
 151                   (PTRACE_TYPE_ARG3) &regs, 0) == -1)
 152         perror_with_name (_("Couldn't write registers"));
 153     }
 154
 155   if (regnum == -1 || m68kbsd_fpregset_supplies_p (regnum))
 156     {
 157       struct fpreg fpregs;
 158
 159       if (ptrace (PT_GETFPREGS, PIDGET (inferior_ptid),
 160                   (PTRACE_TYPE_ARG3) &fpregs, 0) == -1)
 161         perror_with_name (_("Couldn't get floating point status"));
 162
 163       m68kbsd_collect_fpregset (regcache, &fpregs, regnum);
 164
 165       if (ptrace (PT_SETFPREGS, PIDGET (inferior_ptid),
 166                   (PTRACE_TYPE_ARG3) &fpregs, 0) == -1)
 167         perror_with_name (_("Couldn't write floating point status"));
 168     }
 169 }
 170 \f
 171
 172 /* Support for debugging kernel virtual memory images.  */
 173
 174 #include <sys/types.h>
 175 #include <machine/pcb.h>
 176
 177 #include "bsd-kvm.h"
 178
 179 /* OpenBSD doesn't have these.  */
 180 #ifndef PCB_REGS_FP
 181 #define PCB_REGS_FP 10
 182 #endif
 183 #ifndef PCB_REGS_SP
 184 #define PCB_REGS_SP 11
 185 #endif
 186
 187 static int
 188 m68kbsd_supply_pcb (struct regcache *regcache, struct pcb *pcb)
 189 {
 190   int regnum, tmp;
 191   int i = 0;
 192
 193   /* The following is true for NetBSD 1.6.2:
 194
 195      The pcb contains %d2...%d7, %a2...%a7 and %ps.  This accounts for
 196      all callee-saved registers.  From this information we reconstruct
 197      the register state as it would look when we just returned from
 198      cpu_switch().  */
 199
 200   /* The stack pointer shouldn't be zero.  */
 201   if (pcb->pcb_regs[PCB_REGS_SP] == 0)
 202     return 0;
 203
 204   for (regnum = M68K_D2_REGNUM; regnum <= M68K_D7_REGNUM; regnum++)
 205     regcache_raw_supply (regcache, regnum, &pcb->pcb_regs[i++]);
 206   for (regnum = M68K_A2_REGNUM; regnum <= M68K_SP_REGNUM; regnum++)
 207     regcache_raw_supply (regcache, regnum, &pcb->pcb_regs[i++]);
 208
 209   tmp = pcb->pcb_ps & 0xffff;
 210   regcache_raw_supply (regcache, M68K_PS_REGNUM, &tmp);
 211
 212   read_memory (pcb->pcb_regs[PCB_REGS_FP] + 4, (char *) &tmp, sizeof tmp);
 213   regcache_raw_supply (regcache, M68K_PC_REGNUM, &tmp);
 214
 215   return 1;
 216 }
 217 \f
 218
 219 /* Provide a prototype to silence -Wmissing-prototypes.  */
 220 void _initialize_m68kbsd_nat (void);
 221
 222 void
 223 _initialize_m68kbsd_nat (void)
 224 {
 225   struct target_ops *t;
 226
 227   t = inf_ptrace_target ();
 228   t->to_fetch_registers = m68kbsd_fetch_inferior_registers;
 229   t->to_store_registers = m68kbsd_store_inferior_registers;
 230   add_target (t);
 231
 232   /* Support debugging kernel virtual memory images.  */
 233   bsd_kvm_add_target (m68kbsd_supply_pcb);
 234 }