gdb/m68kbsd-nat.c

   1 /* Native-dependent code for Motorola 68000 BSD's.
   2
   3    Copyright 2004 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 2 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, write to the Free Software
  19    Foundation, Inc., 59 Temple Place - Suite 330,
  20    Boston, MA 02111-1307, USA.  */
  21
  22 #include "defs.h"
  23 #include "gdbcore.h"
  24 #include "inferior.h"
  25 #include "regcache.h"
  26
  27 #include "gdb_assert.h"
  28 #include <sys/types.h>
  29 #include <sys/ptrace.h>
  30 #include <machine/reg.h>
  31
  32 #include "m68k-tdep.h"
  33
  34 static int
  35 m68kbsd_gregset_supplies_p (int regnum)
  36 {
  37   return (regnum >= M68K_D0_REGNUM && regnum <= M68K_PC_REGNUM);
  38 }
  39
  40 static int
  41 m68kbsd_fpregset_supplies_p (int regnum)
  42 {
  43   return (regnum >= M68K_FP0_REGNUM && regnum <= M68K_FPI_REGNUM);
  44 }
  45
  46 /* Supply the general-purpose registers stored in GREGS to REGCACHE.  */
  47
  48 static void
  49 m68kbsd_supply_gregset (struct regcache *regcache, const void *gregs)
  50 {
  51   const char *regs = gregs;
  52   int regnum;
  53
  54   for (regnum = M68K_D0_REGNUM; regnum <= M68K_PC_REGNUM; regnum++)
  55     regcache_raw_supply (regcache, regnum, regs + regnum * 4);
  56 }
  57
  58 /* Supply the floating-point registers stored in FPREGS to REGCACHE.  */
  59
  60 static void
  61 m68kbsd_supply_fpregset (struct regcache *regcache, const void *fpregs)
  62 {
  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 (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   char *regs = fpregs;
  96   int i;
  97
  98   for (i = M68K_FP0_REGNUM; i <= M68K_FPI_REGNUM; i++)
  99     {
 100       if (regnum == -1 || regnum == i)
 101         regcache_raw_collect (regcache, i, regs + m68kbsd_fpreg_offset (i));
 102     }
 103 }
 104 \f
 105
 106 /* Fetch register REGNUM from the inferior.  If REGNUM is -1, do this
 107    for all registers (including the floating-point registers).  */
 108
 109 void
 110 fetch_inferior_registers (int regnum)
 111 {
 112   if (regnum == -1 || m68kbsd_gregset_supplies_p (regnum))
 113     {
 114       struct reg regs;
 115
 116       if (ptrace (PT_GETREGS, PIDGET (inferior_ptid),
 117                   (PTRACE_ARG3_TYPE) &regs, 0) == -1)
 118         perror_with_name ("Couldn't get registers");
 119
 120       m68kbsd_supply_gregset (current_regcache, &regs);
 121     }
 122
 123   if (regnum == -1 || m68kbsd_fpregset_supplies_p (regnum))
 124     {
 125       struct fpreg fpregs;
 126
 127       if (ptrace (PT_GETFPREGS, PIDGET (inferior_ptid),
 128                   (PTRACE_ARG3_TYPE) &fpregs, 0) == -1)
 129         perror_with_name ("Couldn't get floating point status");
 130
 131       m68kbsd_supply_fpregset (current_regcache, &fpregs);
 132     }
 133 }
 134
 135 /* Store register REGNUM back into the inferior.  If REGNUM is -1, do
 136    this for all registers (including the floating-point registers).  */
 137
 138 void
 139 store_inferior_registers (int regnum)
 140 {
 141   if (regnum == -1 || m68kbsd_gregset_supplies_p (regnum))
 142     {
 143       struct reg regs;
 144
 145       if (ptrace (PT_GETREGS, PIDGET (inferior_ptid),
 146                   (PTRACE_ARG3_TYPE) &regs, 0) == -1)
 147         perror_with_name ("Couldn't get registers");
 148
 149       m68kbsd_collect_gregset (current_regcache, &regs, regnum);
 150
 151       if (ptrace (PT_SETREGS, PIDGET (inferior_ptid),
 152                   (PTRACE_ARG3_TYPE) &regs, 0) == -1)
 153         perror_with_name ("Couldn't write registers");
 154     }
 155
 156   if (regnum == -1 || m68kbsd_fpregset_supplies_p (regnum))
 157     {
 158       struct fpreg fpregs;
 159
 160       if (ptrace (PT_GETFPREGS, PIDGET (inferior_ptid),
 161                   (PTRACE_ARG3_TYPE) &fpregs, 0) == -1)
 162         perror_with_name ("Couldn't get floating point status");
 163
 164       m68kbsd_collect_fpregset (current_regcache, &fpregs, regnum);
 165
 166       if (ptrace (PT_SETFPREGS, PIDGET (inferior_ptid),
 167                   (PTRACE_ARG3_TYPE) &fpregs, 0) == -1)
 168         perror_with_name ("Couldn't write floating point status");
 169     }
 170 }
 171 \f
 172
 173 /* Support for debugging kernel virtual memory images.  */
 174
 175 #include <sys/types.h>
 176 #include <machine/pcb.h>
 177
 178 #include "bsd-kvm.h"
 179
 180 /* OpenBSD doesn't have these.  */
 181 #ifndef PCB_REGS_FP
 182 #define PCB_REGS_FP 10
 183 #endif
 184 #ifndef PCB_REGS_SP
 185 #define PCB_REGS_SP 11
 186 #endif
 187
 188 static int
 189 m68kbsd_supply_pcb (struct regcache *regcache, struct pcb *pcb)
 190 {
 191   int regnum, tmp;
 192   int i = 0;
 193
 194   /* The following is true for NetBSD 1.6.2:
 195
 196      The pcb contains %d2...%d7, %a2...%a7 and %ps.  This accounts for
 197      all callee-saved registers.  From this information we reconstruct
 198      the register state as it would look when we just returned from
 199      cpu_switch().  */
 200
 201   /* The stack pointer shouldn't be zero.  */
 202   if (pcb->pcb_regs[PCB_REGS_SP] == 0)
 203     return 0;
 204
 205   for (regnum = M68K_D2_REGNUM; regnum <= M68K_D7_REGNUM; regnum++)
 206     regcache_raw_supply (regcache, regnum, &pcb->pcb_regs[i++]);
 207   for (regnum = M68K_A2_REGNUM; regnum <= M68K_SP_REGNUM; regnum++)
 208     regcache_raw_supply (regcache, regnum, &pcb->pcb_regs[i++]);
 209
 210   tmp = pcb->pcb_ps & 0xffff;
 211   regcache_raw_supply (regcache, M68K_PS_REGNUM, &tmp);
 212
 213   read_memory (pcb->pcb_regs[PCB_REGS_FP] + 4, (char *) &tmp, sizeof tmp);
 214   regcache_raw_supply (regcache, M68K_PC_REGNUM, &tmp);
 215
 216   return 1;
 217 }
 218 \f
 219
 220 /* Provide a prototype to silence -Wmissing-prototypes.  */
 221 void _initialize_m68kbsd_nat (void);
 222
 223 void
 224 _initialize_m68kbsd_nat (void)
 225 {
 226   /* Support debugging kernel virtual memory images.  */
 227   bsd_kvm_add_target (m68kbsd_supply_pcb);
 228 }