Subversion Repositories openrisc_2011-10-31

/* Target-dependent code for NetBSD/powerpc.

   Copyright (C) 2002, 2003, 2004, 2005, 2006, 2007, 2008

   Free Software Foundation, Inc.

   Contributed by Wasabi Systems, Inc.

   This file is part of GDB.

   This program is free software; you can redistribute it and/or modify

   it under the terms of the GNU General Public License as published by

   the Free Software Foundation; either version 3 of the License, or

   (at your option) any later version.

   This program is distributed in the hope that it will be useful,

   but WITHOUT ANY WARRANTY; without even the implied warranty of

   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License

   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */

#include "defs.h"

#include "gdbtypes.h"

#include "osabi.h"

#include "regcache.h"

#include "regset.h"

#include "trad-frame.h"

#include "tramp-frame.h"

#include "gdb_assert.h"

#include "gdb_string.h"

#include "ppc-tdep.h"

#include "ppcnbsd-tdep.h"

#include "solib-svr4.h"

/* Register offsets from <machine/reg.h>.  */

struct ppc_reg_offsets ppcnbsd_reg_offsets;

/* Core file support.  */

/* NetBSD/powerpc register sets.  */

struct regset ppcnbsd_gregset =

{

  &ppcnbsd_reg_offsets,

  ppc_supply_gregset

};

struct regset ppcnbsd_fpregset =

{

  &ppcnbsd_reg_offsets,

  ppc_supply_fpregset

};

/* Return the appropriate register set for the core section identified

   by SECT_NAME and SECT_SIZE.  */

static const struct regset *

ppcnbsd_regset_from_core_section (struct gdbarch *gdbarch,

                                  const char *sect_name, size_t sect_size)

{

  if (strcmp (sect_name, ".reg") == 0 && sect_size >= 148)

    return &ppcnbsd_gregset;

  if (strcmp (sect_name, ".reg2") == 0 && sect_size >= 264)

    return &ppcnbsd_fpregset;

  return NULL;

}

/* NetBSD is confused.  It appears that 1.5 was using the correct SVR4

   convention but, 1.6 switched to the below broken convention.  For

   the moment use the broken convention.  Ulgh!.  */

static enum return_value_convention

ppcnbsd_return_value (struct gdbarch *gdbarch, struct type *valtype,

                      struct regcache *regcache, gdb_byte *readbuf,

                      const gdb_byte *writebuf)

{

#if 0

  if ((TYPE_CODE (valtype) == TYPE_CODE_STRUCT

       || TYPE_CODE (valtype) == TYPE_CODE_UNION)

      && !((TYPE_LENGTH (valtype) == 16 || TYPE_LENGTH (valtype) == 8)

            && TYPE_VECTOR (valtype))

      && !(TYPE_LENGTH (valtype) == 1

           || TYPE_LENGTH (valtype) == 2

           || TYPE_LENGTH (valtype) == 4

           || TYPE_LENGTH (valtype) == 8))

    return RETURN_VALUE_STRUCT_CONVENTION;

  else

#endif

    return ppc_sysv_abi_broken_return_value (gdbarch, valtype, regcache,

                                             readbuf, writebuf);

}

/* Signal trampolines.  */

static const struct tramp_frame ppcnbsd2_sigtramp;

static void

ppcnbsd_sigtramp_cache_init (const struct tramp_frame *self,

                             struct frame_info *next_frame,

                             struct trad_frame_cache *this_cache,

                             CORE_ADDR func)

{

  struct gdbarch *gdbarch = get_frame_arch (next_frame);

  struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);

  CORE_ADDR addr, base;

  int i;

  base = frame_unwind_register_unsigned (next_frame,

                                         gdbarch_sp_regnum (gdbarch));

  if (self == &ppcnbsd2_sigtramp)

    addr = base + 0x10 + 2 * tdep->wordsize;

  else

    addr = base + 0x18 + 2 * tdep->wordsize;

  for (i = 0; i < ppc_num_gprs; i++, addr += tdep->wordsize)

    {

      int regnum = i + tdep->ppc_gp0_regnum;

      trad_frame_set_reg_addr (this_cache, regnum, addr);

    }

  trad_frame_set_reg_addr (this_cache, tdep->ppc_lr_regnum, addr);

  addr += tdep->wordsize;

  trad_frame_set_reg_addr (this_cache, tdep->ppc_cr_regnum, addr);

  addr += tdep->wordsize;

  trad_frame_set_reg_addr (this_cache, tdep->ppc_xer_regnum, addr);

  addr += tdep->wordsize;

  trad_frame_set_reg_addr (this_cache, tdep->ppc_ctr_regnum, addr);

  addr += tdep->wordsize;

  trad_frame_set_reg_addr (this_cache, gdbarch_pc_regnum (gdbarch),

                           addr); /* SRR0? */

  addr += tdep->wordsize;

  /* Construct the frame ID using the function start.  */

  trad_frame_set_id (this_cache, frame_id_build (base, func));

}

static const struct tramp_frame ppcnbsd_sigtramp =

{

  SIGTRAMP_FRAME,

  4,

  {

    { 0x3821fff0, -1 },         /* add r1,r1,-16 */

    { 0x4e800021, -1 },         /* blrl */

    { 0x38610018, -1 },         /* addi r3,r1,24 */

    { 0x38000127, -1 },         /* li r0,295 */

    { 0x44000002, -1 },         /* sc */

    { 0x38000001, -1 },         /* li r0,1 */

    { 0x44000002, -1 },         /* sc */

    { TRAMP_SENTINEL_INSN, -1 }

  },

  ppcnbsd_sigtramp_cache_init

};

/* NetBSD 2.0 introduced a slightly different signal trampoline.  */

static const struct tramp_frame ppcnbsd2_sigtramp =

{

  SIGTRAMP_FRAME,

  4,

  {

    { 0x3821fff0, -1 },         /* add r1,r1,-16 */

    { 0x4e800021, -1 },         /* blrl */

    { 0x38610010, -1 },         /* addi r3,r1,16 */

    { 0x38000127, -1 },         /* li r0,295 */

    { 0x44000002, -1 },         /* sc */

    { 0x38000001, -1 },         /* li r0,1 */

    { 0x44000002, -1 },         /* sc */

    { TRAMP_SENTINEL_INSN, -1 }

  },

  ppcnbsd_sigtramp_cache_init

};

static void

ppcnbsd_init_abi (struct gdbarch_info info,

                  struct gdbarch *gdbarch)

{

  /* For NetBSD, this is an on again, off again thing.  Some systems

     do use the broken struct convention, and some don't.  */

  set_gdbarch_return_value (gdbarch, ppcnbsd_return_value);

  /* NetBSD uses SVR4-style shared libraries.  */

  set_solib_svr4_fetch_link_map_offsets

    (gdbarch, svr4_ilp32_fetch_link_map_offsets);

  set_gdbarch_regset_from_core_section

    (gdbarch, ppcnbsd_regset_from_core_section);

  tramp_frame_prepend_unwinder (gdbarch, &ppcnbsd_sigtramp);

  tramp_frame_prepend_unwinder (gdbarch, &ppcnbsd2_sigtramp);

}

/* Provide a prototype to silence -Wmissing-prototypes.  */

void _initialize_ppcnbsd_tdep (void);

void

_initialize_ppcnbsd_tdep (void)

{

  gdbarch_register_osabi (bfd_arch_powerpc, 0, GDB_OSABI_NETBSD_ELF,

                          ppcnbsd_init_abi);

  /* Avoid initializing the register offsets again if they were

     already initailized by ppcnbsd-nat.c.  */

  if (ppcnbsd_reg_offsets.pc_offset == 0)

    {

      /* General-purpose registers.  */

      ppcnbsd_reg_offsets.r0_offset = 0;

      ppcnbsd_reg_offsets.gpr_size = 4;

      ppcnbsd_reg_offsets.xr_size = 4;

      ppcnbsd_reg_offsets.lr_offset = 128;

      ppcnbsd_reg_offsets.cr_offset = 132;

      ppcnbsd_reg_offsets.xer_offset = 136;

      ppcnbsd_reg_offsets.ctr_offset = 140;

      ppcnbsd_reg_offsets.pc_offset = 144;

      ppcnbsd_reg_offsets.ps_offset = -1;

      ppcnbsd_reg_offsets.mq_offset = -1;

      /* Floating-point registers.  */

      ppcnbsd_reg_offsets.f0_offset = 0;

      ppcnbsd_reg_offsets.fpscr_offset = 256;

      ppcnbsd_reg_offsets.fpscr_size = 4;

      /* AltiVec registers.  */

      ppcnbsd_reg_offsets.vr0_offset = 0;

      ppcnbsd_reg_offsets.vrsave_offset = 512;

      ppcnbsd_reg_offsets.vscr_offset = 524;

    }

}