gdb/m68k-bsd-tdep.c

   1 /* Target-dependent code for Motorola 68000 BSD's.
   2
   3    Copyright (C) 2004-2024 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 "arch-utils.h"
  21 #include "frame.h"
  22 #include "osabi.h"
  23 #include "regcache.h"
  24 #include "regset.h"
  25 #include "trad-frame.h"
  26 #include "tramp-frame.h"
  27 #include "gdbtypes.h"
  28
  29 #include "m68k-tdep.h"
  30 #include "solib-svr4.h"
  31
  32 /* Core file support.  */
  33
  34 /* Sizeof `struct reg' in <machine/reg.h>.  */
  35 #define M68KBSD_SIZEOF_GREGS    (18 * 4)
  36
  37 /* Sizeof `struct fpreg' in <machine/reg.h.  */
  38 #define M68KBSD_SIZEOF_FPREGS   (((8 * 3) + 3) * 4)
  39
  40 int
  41 m68kbsd_fpreg_offset (struct gdbarch *gdbarch, int regnum)
  42 {
  43   int fp_len = gdbarch_register_type (gdbarch, regnum)->length ();
  44
  45   if (regnum >= M68K_FPC_REGNUM)
  46     return 8 * fp_len + (regnum - M68K_FPC_REGNUM) * 4;
  47
  48   return (regnum - M68K_FP0_REGNUM) * fp_len;
  49 }
  50
  51 /* Supply register REGNUM from the buffer specified by FPREGS and LEN
  52    in the floating-point register set REGSET to register cache
  53    REGCACHE.  If REGNUM is -1, do this for all registers in REGSET.  */
  54
  55 static void
  56 m68kbsd_supply_fpregset (const struct regset *regset,
  57                          struct regcache *regcache,
  58                          int regnum, const void *fpregs, size_t len)
  59 {
  60   struct gdbarch *gdbarch = regcache->arch ();
  61   const gdb_byte *regs = (const gdb_byte *) fpregs;
  62   int i;
  63
  64   gdb_assert (len >= M68KBSD_SIZEOF_FPREGS);
  65
  66   for (i = M68K_FP0_REGNUM; i <= M68K_PC_REGNUM; i++)
  67     {
  68       if (regnum == i || regnum == -1)
  69         regcache->raw_supply (i, regs + m68kbsd_fpreg_offset (gdbarch, i));
  70     }
  71 }
  72
  73 /* Supply register REGNUM from the buffer specified by GREGS and LEN
  74    in the general-purpose register set REGSET to register cache
  75    REGCACHE.  If REGNUM is -1, do this for all registers in REGSET.  */
  76
  77 static void
  78 m68kbsd_supply_gregset (const struct regset *regset,
  79                         struct regcache *regcache,
  80                         int regnum, const void *gregs, size_t len)
  81 {
  82   const gdb_byte *regs = (const gdb_byte *) gregs;
  83   int i;
  84
  85   gdb_assert (len >= M68KBSD_SIZEOF_GREGS);
  86
  87   for (i = M68K_D0_REGNUM; i <= M68K_PC_REGNUM; i++)
  88     {
  89       if (regnum == i || regnum == -1)
  90         regcache->raw_supply (i, regs + i * 4);
  91     }
  92
  93   if (len >= M68KBSD_SIZEOF_GREGS + M68KBSD_SIZEOF_FPREGS)
  94     {
  95       regs += M68KBSD_SIZEOF_GREGS;
  96       len -= M68KBSD_SIZEOF_GREGS;
  97       m68kbsd_supply_fpregset (regset, regcache, regnum, regs, len);
  98     }
  99 }
 100
 101 /* Motorola 68000 register sets.  */
 102
 103 static const struct regset m68kbsd_gregset =
 104 {
 105   NULL,
 106   m68kbsd_supply_gregset,
 107   NULL,
 108   REGSET_VARIABLE_SIZE
 109 };
 110
 111 static const struct regset m68kbsd_fpregset =
 112 {
 113   NULL,
 114   m68kbsd_supply_fpregset
 115 };
 116
 117 /* Iterate over core file register note sections.  */
 118
 119 static void
 120 m68kbsd_iterate_over_regset_sections (struct gdbarch *gdbarch,
 121                                       iterate_over_regset_sections_cb *cb,
 122                                       void *cb_data,
 123                                       const struct regcache *regcache)
 124 {
 125   cb (".reg", M68KBSD_SIZEOF_GREGS, M68KBSD_SIZEOF_GREGS, &m68kbsd_gregset,
 126       NULL, cb_data);
 127   cb (".reg2", M68KBSD_SIZEOF_FPREGS, M68KBSD_SIZEOF_FPREGS, &m68kbsd_fpregset,
 128       NULL, cb_data);
 129 }
 130 \f
 131
 132 static void
 133 m68kbsd_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
 134 {
 135   m68k_gdbarch_tdep *tdep = gdbarch_tdep<m68k_gdbarch_tdep> (gdbarch);
 136
 137   tdep->jb_pc = 5;
 138   tdep->jb_elt_size = 4;
 139
 140   set_gdbarch_decr_pc_after_break (gdbarch, 2);
 141
 142   set_gdbarch_iterate_over_regset_sections
 143     (gdbarch, m68kbsd_iterate_over_regset_sections);
 144
 145   /* NetBSD ELF uses the SVR4 ABI.  */
 146   m68k_svr4_init_abi (info, gdbarch);
 147   tdep->struct_return = pcc_struct_return;
 148
 149   /* NetBSD ELF uses SVR4-style shared libraries.  */
 150   set_solib_svr4_fetch_link_map_offsets
 151     (gdbarch, svr4_ilp32_fetch_link_map_offsets);
 152 }
 153
 154 void _initialize_m68kbsd_tdep ();
 155 void
 156 _initialize_m68kbsd_tdep ()
 157 {
 158   gdbarch_register_osabi (bfd_arch_m68k, 0, GDB_OSABI_NETBSD,
 159                           m68kbsd_init_abi);
 160 }