gdb/m68klinux-nat.c

   1 /* Motorola m68k native support for Linux
   2    Copyright (C) 1996,1998 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., 59 Temple Place - Suite 330,
  19    Boston, MA 02111-1307, USA.  */
  20
  21 #include "defs.h"
  22 #include "frame.h"
  23 #include "inferior.h"
  24 #include "language.h"
  25 #include "gdbcore.h"
  26
  27 #ifdef USG
  28 #include <sys/types.h>
  29 #endif
  30
  31 #include <sys/param.h>
  32 #include <sys/dir.h>
  33 #include <signal.h>
  34 #include <sys/user.h>
  35 #include <sys/ioctl.h>
  36 #include <fcntl.h>
  37 #include <sys/procfs.h>
  38
  39 #include <sys/file.h>
  40 #include "gdb_stat.h"
  41
  42 #include "floatformat.h"
  43
  44 #include "target.h"
  45 \f
  46
  47 /* This table must line up with REGISTER_NAMES in tm-m68k.h */
  48 static const int regmap[] =
  49 {
  50   PT_D0, PT_D1, PT_D2, PT_D3, PT_D4, PT_D5, PT_D6, PT_D7,
  51   PT_A0, PT_A1, PT_A2, PT_A3, PT_A4, PT_A5, PT_A6, PT_USP,
  52   PT_SR, PT_PC,
  53   /* PT_FP0, ..., PT_FP7 */
  54   21, 24, 27, 30, 33, 36, 39, 42,
  55   /* PT_FPCR, PT_FPSR, PT_FPIAR */
  56   45, 46, 47
  57 };
  58
  59 /* BLOCKEND is the value of u.u_ar0, and points to the place where GS
  60    is stored.  */
  61
  62 int
  63 m68k_linux_register_u_addr (blockend, regnum)
  64      int blockend;
  65      int regnum;
  66 {
  67   return (blockend + 4 * regmap[regnum]);
  68 }
  69
  70 /*  Given a pointer to a general register set in /proc format (gregset_t *),
  71    unpack the register contents and supply them as gdb's idea of the current
  72    register values. */
  73
  74
  75 /* Note both m68k-tdep.c and m68klinux-nat.c contain definitions
  76    for supply_gregset and supply_fpregset. The definitions
  77    in m68k-tdep.c are valid if USE_PROC_FS is defined. Otherwise,
  78    the definitions in m68klinux-nat.c will be used. This is a
  79    bit of a hack. The supply_* routines do not belong in
  80    *_tdep.c files. But, there are several lynx ports that currently
  81    depend on these definitions. */
  82
  83 #ifndef USE_PROC_FS
  84
  85 void
  86 supply_gregset (gregsetp)
  87      gregset_t *gregsetp;
  88 {
  89   int regi;
  90
  91   for (regi = D0_REGNUM; regi <= SP_REGNUM; regi++)
  92     supply_register (regi, (char *) (*gregsetp + regmap[regi]));
  93   supply_register (PS_REGNUM, (char *) (*gregsetp + PT_SR));
  94   supply_register (PC_REGNUM, (char *) (*gregsetp + PT_PC));
  95 }
  96
  97 /*  Given a pointer to a floating point register set in /proc format
  98    (fpregset_t *), unpack the register contents and supply them as gdb's
  99    idea of the current floating point register values. */
 100
 101 void
 102 supply_fpregset (fpregsetp)
 103      fpregset_t *fpregsetp;
 104 {
 105   int regi;
 106
 107   for (regi = FP0_REGNUM; regi < FPC_REGNUM; regi++)
 108     supply_register (regi, (char *) &fpregsetp->fpregs[(regi - FP0_REGNUM) * 3]);
 109   supply_register (FPC_REGNUM, (char *) &fpregsetp->fpcntl[0]);
 110   supply_register (FPS_REGNUM, (char *) &fpregsetp->fpcntl[1]);
 111   supply_register (FPI_REGNUM, (char *) &fpregsetp->fpcntl[2]);
 112 }
 113
 114 #endif
 115 \f
 116
 117 int
 118 kernel_u_size ()
 119 {
 120   return (sizeof (struct user));
 121 }
 122 \f
 123 /* Return non-zero if PC points into the signal trampoline.  */
 124
 125 int
 126 in_sigtramp (pc)
 127      CORE_ADDR pc;
 128 {
 129   CORE_ADDR sp;
 130   char buf[TARGET_SHORT_BIT / TARGET_CHAR_BIT];
 131   int insn;
 132
 133   sp = read_register (SP_REGNUM);
 134   if (pc - 2 < sp)
 135     return 0;
 136
 137   if (read_memory_nobpt (pc, buf, sizeof (buf)))
 138     return 0;
 139   insn = extract_unsigned_integer (buf, sizeof (buf));
 140   if (insn == 0xdefc            /* addaw #,sp */
 141       || insn == 0x7077         /* moveq #119,d0 */
 142       || insn == 0x4e40         /* trap #0 */
 143       || insn == 0x203c /* movel #,d0 */ )
 144     return 1;
 145
 146   if (read_memory_nobpt (pc - 2, buf, sizeof (buf)))
 147     return 0;
 148   insn = extract_unsigned_integer (buf, sizeof (buf));
 149   if (insn == 0xdefc            /* addaw #,sp */
 150       || insn == 0x7077         /* moveq #119,d0 */
 151       || insn == 0x4e40         /* trap #0 */
 152       || insn == 0x203c /* movel #,d0 */ )
 153     return 1;
 154
 155   return 0;
 156 }