[thirdparty/binutils-gdb.git] / gdb / ppcobsd-tdep.c

/* Target-dependent code for OpenBSD/powerpc.

   Copyright (C) 2004, 2005, 2006, 2007 Free Software Foundation, 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 2 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, write to the Free Software
   Foundation, Inc., 51 Franklin Street, Fifth Floor,
   Boston, MA 02110-1301, USA.  */

#include "defs.h"
#include "arch-utils.h"
#include "floatformat.h"
#include "frame.h"
#include "frame-unwind.h"
#include "osabi.h"
#include "regcache.h"
#include "regset.h"
#include "symtab.h"
#include "trad-frame.h"

#include "gdb_assert.h"
#include "gdb_string.h"

#include "ppc-tdep.h"
#include "ppcobsd-tdep.h"
#include "solib-svr4.h"

/* Register offsets from <machine/reg.h>.  */
struct ppc_reg_offsets ppcobsd_reg_offsets;
struct ppc_reg_offsets ppcobsd_fpreg_offsets;
\f

/* Core file support.  */

/* Supply register REGNUM in the general-purpose register set REGSET
   from the buffer specified by GREGS and LEN to register cache
   REGCACHE.  If REGNUM is -1, do this for all registers in REGSET.  */

void
ppcobsd_supply_gregset (const struct regset *regset,
			struct regcache *regcache, int regnum,
			const void *gregs, size_t len)
{
  /* FIXME: jimb/2004-05-05: Some PPC variants don't have floating
     point registers.  Traditionally, GDB's register set has still
     listed the floating point registers for such machines, so this
     code is harmless.  However, the new E500 port actually omits the
     floating point registers entirely from the register set --- they
     don't even have register numbers assigned to them.

     It's not clear to me how best to update this code, so this assert
     will alert the first person to encounter the OpenBSD/E500
     combination to the problem.  */
  gdb_assert (ppc_floating_point_unit_p (current_gdbarch));

  ppc_supply_gregset (regset, regcache, regnum, gregs, len);
  ppc_supply_fpregset (regset, regcache, regnum, gregs, len);
}

/* Collect register REGNUM in the general-purpose register set
   REGSET. from register cache REGCACHE into the buffer specified by
   GREGS and LEN.  If REGNUM is -1, do this for all registers in
   REGSET.  */

void
ppcobsd_collect_gregset (const struct regset *regset,
			 const struct regcache *regcache, int regnum,
			 void *gregs, size_t len)
{
  /* FIXME: jimb/2004-05-05: Some PPC variants don't have floating
     point registers.  Traditionally, GDB's register set has still
     listed the floating point registers for such machines, so this
     code is harmless.  However, the new E500 port actually omits the
     floating point registers entirely from the register set --- they
     don't even have register numbers assigned to them.

     It's not clear to me how best to update this code, so this assert
     will alert the first person to encounter the OpenBSD/E500
     combination to the problem.  */
  gdb_assert (ppc_floating_point_unit_p (current_gdbarch));

  ppc_collect_gregset (regset, regcache, regnum, gregs, len);
  ppc_collect_fpregset (regset, regcache, regnum, gregs, len);
}

/* OpenBSD/powerpc register set.  */

struct regset ppcobsd_gregset =
{
  &ppcobsd_reg_offsets,
  ppcobsd_supply_gregset
};

struct regset ppcobsd_fpregset =
{
  &ppcobsd_fpreg_offsets,
  ppc_supply_fpregset
};

/* Return the appropriate register set for the core section identified
   by SECT_NAME and SECT_SIZE.  */

static const struct regset *
ppcobsd_regset_from_core_section (struct gdbarch *gdbarch,
				  const char *sect_name, size_t sect_size)
{
  if (strcmp (sect_name, ".reg") == 0 && sect_size >= 412)
    return &ppcobsd_gregset;

  return NULL;
}
\f

/* Signal trampolines.  */

/* Since OpenBSD 3.2, the sigtramp routine is mapped at a random page
   in virtual memory.  The randomness makes it somewhat tricky to
   detect it, but fortunately we can rely on the fact that the start
   of the sigtramp routine is page-aligned.  We recognize the
   trampoline by looking for the code that invokes the sigreturn
   system call.  The offset where we can find that code varies from
   release to release.

   By the way, the mapping mentioned above is read-only, so you cannot
   place a breakpoint in the signal trampoline.  */

/* Default page size.  */
static const int ppcobsd_page_size = 4096;

/* Offset for sigreturn(2).  */
static const int ppcobsd_sigreturn_offset[] = {
  0x98,				/* OpenBSD 3.8 */
  0x0c,				/* OpenBSD 3.2 */
  -1
};

static int
ppcobsd_sigtramp_p (struct frame_info *next_frame)
{
  CORE_ADDR pc = frame_pc_unwind (next_frame);
  CORE_ADDR start_pc = (pc & ~(ppcobsd_page_size - 1));
  const int *offset;
  char *name;

  find_pc_partial_function (pc, &name, NULL, NULL);
  if (name)
    return 0;

  for (offset = ppcobsd_sigreturn_offset; *offset != -1; offset++)
    {
      gdb_byte buf[2 * PPC_INSN_SIZE];
      unsigned long insn;

      if (!safe_frame_unwind_memory (next_frame, start_pc + *offset,
				     buf, sizeof buf))
	continue;

      /* Check for "li r0,SYS_sigreturn".  */
      insn = extract_unsigned_integer (buf, PPC_INSN_SIZE);
      if (insn != 0x38000067)
	continue;

      /* Check for "sc".  */
      insn = extract_unsigned_integer (buf + PPC_INSN_SIZE, PPC_INSN_SIZE);
      if (insn != 0x44000002)
	continue;

      return 1;
    }

  return 0;
}

static struct trad_frame_cache *
ppcobsd_sigtramp_frame_cache (struct frame_info *next_frame, void **this_cache)
{
  struct gdbarch *gdbarch = get_frame_arch (next_frame);
  struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
  struct trad_frame_cache *cache;
  CORE_ADDR addr, base, func;
  gdb_byte buf[PPC_INSN_SIZE];
  unsigned long insn, sigcontext_offset;
  int i;

  if (*this_cache)
    return *this_cache;

  cache = trad_frame_cache_zalloc (next_frame);
  *this_cache = cache;

  func = frame_pc_unwind (next_frame);
  func &= ~(ppcobsd_page_size - 1);
  if (!safe_frame_unwind_memory (next_frame, func, buf, sizeof buf))
    return cache;

  /* Calculate the offset where we can find `struct sigcontext'.  We
     base our calculation on the amount of stack space reserved by the
     first instruction of the signal trampoline.  */
  insn = extract_unsigned_integer (buf, PPC_INSN_SIZE);
  sigcontext_offset = (0x10000 - (insn & 0x0000ffff)) + 8;

  base = frame_unwind_register_unsigned (next_frame, SP_REGNUM);
  addr = base + sigcontext_offset + 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 (cache, regnum, addr);
    }
  trad_frame_set_reg_addr (cache, tdep->ppc_lr_regnum, addr);
  addr += tdep->wordsize;
  trad_frame_set_reg_addr (cache, tdep->ppc_cr_regnum, addr);
  addr += tdep->wordsize;
  trad_frame_set_reg_addr (cache, tdep->ppc_xer_regnum, addr);
  addr += tdep->wordsize;
  trad_frame_set_reg_addr (cache, tdep->ppc_ctr_regnum, addr);
  addr += tdep->wordsize;
  trad_frame_set_reg_addr (cache, PC_REGNUM, addr); /* SRR0? */
  addr += tdep->wordsize;

  /* Construct the frame ID using the function start.  */
  trad_frame_set_id (cache, frame_id_build (base, func));

  return cache;
}

static void
ppcobsd_sigtramp_frame_this_id (struct frame_info *next_frame,
				void **this_cache, struct frame_id *this_id)
{
  struct trad_frame_cache *cache =
    ppcobsd_sigtramp_frame_cache (next_frame, this_cache);

  trad_frame_get_id (cache, this_id);
}

static void
ppcobsd_sigtramp_frame_prev_register (struct frame_info *next_frame,
				      void **this_cache, int regnum,
				      int *optimizedp, enum lval_type *lvalp,
				      CORE_ADDR *addrp, int *realnump,
				      gdb_byte *valuep)
{
  struct trad_frame_cache *cache =
    ppcobsd_sigtramp_frame_cache (next_frame, this_cache);

  trad_frame_get_register (cache, next_frame, regnum,
			   optimizedp, lvalp, addrp, realnump, valuep);
}

static const struct frame_unwind ppcobsd_sigtramp_frame_unwind = {
  SIGTRAMP_FRAME,
  ppcobsd_sigtramp_frame_this_id,
  ppcobsd_sigtramp_frame_prev_register
};

static const struct frame_unwind *
ppcobsd_sigtramp_frame_sniffer (struct frame_info *next_frame)
{
  if (ppcobsd_sigtramp_p (next_frame))
    return &ppcobsd_sigtramp_frame_unwind;

  return NULL;
}
\f

static void
ppcobsd_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
{
  /* OpenBSD doesn't support the 128-bit `long double' from the psABI.  */
  set_gdbarch_long_double_bit (gdbarch, 64);
  set_gdbarch_long_double_format (gdbarch, &floatformat_ieee_double_big);

  /* OpenBSD currently uses a broken GCC.  */
  set_gdbarch_return_value (gdbarch, ppc_sysv_abi_broken_return_value);

  /* OpenBSD 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, ppcobsd_regset_from_core_section);

  frame_unwind_append_sniffer (gdbarch, ppcobsd_sigtramp_frame_sniffer);
}
\f

/* OpenBSD uses uses the traditional NetBSD core file format, even for
   ports that use ELF.  */
#define GDB_OSABI_NETBSD_CORE GDB_OSABI_OPENBSD_ELF

static enum gdb_osabi
ppcobsd_core_osabi_sniffer (bfd *abfd)
{
  if (strcmp (bfd_get_target (abfd), "netbsd-core") == 0)
    return GDB_OSABI_NETBSD_CORE;

  return GDB_OSABI_UNKNOWN;
}
\f

/* Provide a prototype to silence -Wmissing-prototypes.  */
void _initialize_ppcobsd_tdep (void);

void
_initialize_ppcobsd_tdep (void)
{
  /* BFD doesn't set a flavour for NetBSD style a.out core files.  */
  gdbarch_register_osabi_sniffer (bfd_arch_powerpc, bfd_target_unknown_flavour,
                                  ppcobsd_core_osabi_sniffer);

  gdbarch_register_osabi (bfd_arch_rs6000, 0, GDB_OSABI_OPENBSD_ELF,
			  ppcobsd_init_abi);
  gdbarch_register_osabi (bfd_arch_powerpc, 0, GDB_OSABI_OPENBSD_ELF,
			  ppcobsd_init_abi);

  /* Avoid initializing the register offsets again if they were
     already initailized by ppcobsd-nat.c.  */
  if (ppcobsd_reg_offsets.pc_offset == 0)
    {
      /* General-purpose registers.  */
      ppcobsd_reg_offsets.r0_offset = 0;
      ppcobsd_reg_offsets.pc_offset = 384;
      ppcobsd_reg_offsets.ps_offset = 388;
      ppcobsd_reg_offsets.cr_offset = 392;
      ppcobsd_reg_offsets.lr_offset = 396;
      ppcobsd_reg_offsets.ctr_offset = 400;
      ppcobsd_reg_offsets.xer_offset = 404;
      ppcobsd_reg_offsets.mq_offset = 408;

      /* Floating-point registers.  */
      ppcobsd_reg_offsets.f0_offset = 128;
      ppcobsd_reg_offsets.fpscr_offset = -1;

      /* AltiVec registers.  */
      ppcobsd_reg_offsets.vr0_offset = 0;
      ppcobsd_reg_offsets.vscr_offset = 512;
      ppcobsd_reg_offsets.vrsave_offset = 520;
    }

  if (ppcobsd_fpreg_offsets.fpscr_offset == 0)
    {
      /* Floating-point registers.  */
      ppcobsd_reg_offsets.f0_offset = 0;
      ppcobsd_reg_offsets.fpscr_offset = 256;
    }
}
Commit	Line	Data
d195bc9f MK	1	/* Target-dependent code for OpenBSD/powerpc.
d195bc9f MK	2
6aba47ca	3	Copyright (C) 2004, 2005, 2006, 2007 Free Software Foundation, Inc.
d195bc9f MK	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
197e01b6 EZ	19	Foundation, Inc., 51 Franklin Street, Fifth Floor,
197e01b6 EZ	20	Boston, MA 02110-1301, USA. */
d195bc9f MK	21
	22	#include "defs.h"
	23	#include "arch-utils.h"
5a49dfd0	24	#include "floatformat.h"
0dbe1904 MK	25	#include "frame.h"
0dbe1904 MK	26	#include "frame-unwind.h"
d195bc9f MK	27	#include "osabi.h"
	28	#include "regcache.h"
	29	#include "regset.h"
0dbe1904	30	#include "symtab.h"
18b2ae85	31	#include "trad-frame.h"
d195bc9f	32
18b2ae85	33	#include "gdb_assert.h"
d195bc9f MK	34	#include "gdb_string.h"
	35
	36	#include "ppc-tdep.h"
	37	#include "ppcobsd-tdep.h"
	38	#include "solib-svr4.h"
	39
	40	/* Register offsets from <machine/reg.h>. */
	41	struct ppc_reg_offsets ppcobsd_reg_offsets;
8599da2d	42	struct ppc_reg_offsets ppcobsd_fpreg_offsets;
d195bc9f MK	43	\f
	44
	45	/* Core file support. */
	46
	47	/* Supply register REGNUM in the general-purpose register set REGSET
	48	from the buffer specified by GREGS and LEN to register cache
	49	REGCACHE. If REGNUM is -1, do this for all registers in REGSET. */
	50
	51	void
	52	ppcobsd_supply_gregset (const struct regset *regset,
	53	struct regcache *regcache, int regnum,
	54	const void *gregs, size_t len)
	55	{
383f0f5b JB	56	/* FIXME: jimb/2004-05-05: Some PPC variants don't have floating
	57	point registers. Traditionally, GDB's register set has still
	58	listed the floating point registers for such machines, so this
	59	code is harmless. However, the new E500 port actually omits the
	60	floating point registers entirely from the register set --- they
	61	don't even have register numbers assigned to them.
	62
	63	It's not clear to me how best to update this code, so this assert
	64	will alert the first person to encounter the OpenBSD/E500
	65	combination to the problem. */
	66	gdb_assert (ppc_floating_point_unit_p (current_gdbarch));
	67
d195bc9f MK	68	ppc_supply_gregset (regset, regcache, regnum, gregs, len);
	69	ppc_supply_fpregset (regset, regcache, regnum, gregs, len);
	70	}
	71
	72	/* Collect register REGNUM in the general-purpose register set
	73	REGSET. from register cache REGCACHE into the buffer specified by
	74	GREGS and LEN. If REGNUM is -1, do this for all registers in
	75	REGSET. */
	76
	77	void
	78	ppcobsd_collect_gregset (const struct regset *regset,
	79	const struct regcache *regcache, int regnum,
	80	void *gregs, size_t len)
	81	{
383f0f5b JB	82	/* FIXME: jimb/2004-05-05: Some PPC variants don't have floating
	83	point registers. Traditionally, GDB's register set has still
	84	listed the floating point registers for such machines, so this
	85	code is harmless. However, the new E500 port actually omits the
	86	floating point registers entirely from the register set --- they
	87	don't even have register numbers assigned to them.
	88
	89	It's not clear to me how best to update this code, so this assert
	90	will alert the first person to encounter the OpenBSD/E500
	91	combination to the problem. */
	92	gdb_assert (ppc_floating_point_unit_p (current_gdbarch));
	93
d195bc9f MK	94	ppc_collect_gregset (regset, regcache, regnum, gregs, len);
	95	ppc_collect_fpregset (regset, regcache, regnum, gregs, len);
	96	}
	97
5d6210f0	98	/* OpenBSD/powerpc register set. */
d195bc9f MK	99
	100	struct regset ppcobsd_gregset =
	101	{
	102	&ppcobsd_reg_offsets,
	103	ppcobsd_supply_gregset
	104	};
	105
8599da2d MK	106	struct regset ppcobsd_fpregset =
	107	{
	108	&ppcobsd_fpreg_offsets,
	109	ppc_supply_fpregset
	110	};
	111
d195bc9f MK	112	/* Return the appropriate register set for the core section identified
	113	by SECT_NAME and SECT_SIZE. */
	114
	115	static const struct regset *
	116	ppcobsd_regset_from_core_section (struct gdbarch *gdbarch,
	117	const char *sect_name, size_t sect_size)
	118	{
	119	if (strcmp (sect_name, ".reg") == 0 && sect_size >= 412)
	120	return &ppcobsd_gregset;
	121
	122	return NULL;
	123	}
	124	\f
	125
18b2ae85 MK	126	/* Signal trampolines. */
18b2ae85 MK	127
0dbe1904 MK	128	/* Since OpenBSD 3.2, the sigtramp routine is mapped at a random page
	129	in virtual memory. The randomness makes it somewhat tricky to
	130	detect it, but fortunately we can rely on the fact that the start
	131	of the sigtramp routine is page-aligned. We recognize the
	132	trampoline by looking for the code that invokes the sigreturn
	133	system call. The offset where we can find that code varies from
	134	release to release.
	135
	136	By the way, the mapping mentioned above is read-only, so you cannot
	137	place a breakpoint in the signal trampoline. */
	138
	139	/* Default page size. */
	140	static const int ppcobsd_page_size = 4096;
	141
	142	/* Offset for sigreturn(2). */
	143	static const int ppcobsd_sigreturn_offset[] = {
	144	0x98, /* OpenBSD 3.8 */
	145	0x0c, /* OpenBSD 3.2 */
	146	-1
	147	};
	148
	149	static int
	150	ppcobsd_sigtramp_p (struct frame_info *next_frame)
	151	{
	152	CORE_ADDR pc = frame_pc_unwind (next_frame);
	153	CORE_ADDR start_pc = (pc & ~(ppcobsd_page_size - 1));
	154	const int *offset;
	155	char *name;
	156
	157	find_pc_partial_function (pc, &name, NULL, NULL);
	158	if (name)
	159	return 0;
	160
	161	for (offset = ppcobsd_sigreturn_offset; *offset != -1; offset++)
	162	{
	163	gdb_byte buf[2 * PPC_INSN_SIZE];
	164	unsigned long insn;
	165
	166	if (!safe_frame_unwind_memory (next_frame, start_pc + *offset,
	167	buf, sizeof buf))
	168	continue;
	169
	170	/* Check for "li r0,SYS_sigreturn". */
	171	insn = extract_unsigned_integer (buf, PPC_INSN_SIZE);
	172	if (insn != 0x38000067)
	173	continue;
	174
	175	/* Check for "sc". */
	176	insn = extract_unsigned_integer (buf + PPC_INSN_SIZE, PPC_INSN_SIZE);
	177	if (insn != 0x44000002)
	178	continue;
	179
	180	return 1;
	181	}
	182
	183	return 0;
	184	}
	185
	186	static struct trad_frame_cache *
	187	ppcobsd_sigtramp_frame_cache (struct frame_info next_frame, void *this_cache)
18b2ae85 MK	188	{
	189	struct gdbarch *gdbarch = get_frame_arch (next_frame);
	190	struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
0dbe1904 MK	191	struct trad_frame_cache *cache;
	192	CORE_ADDR addr, base, func;
	193	gdb_byte buf[PPC_INSN_SIZE];
	194	unsigned long insn, sigcontext_offset;
18b2ae85 MK	195	int i;
18b2ae85 MK	196
0dbe1904 MK	197	if (*this_cache)
	198	return *this_cache;
	199
	200	cache = trad_frame_cache_zalloc (next_frame);
	201	*this_cache = cache;
	202
	203	func = frame_pc_unwind (next_frame);
	204	func &= ~(ppcobsd_page_size - 1);
	205	if (!safe_frame_unwind_memory (next_frame, func, buf, sizeof buf))
	206	return cache;
	207
	208	/* Calculate the offset where we can find `struct sigcontext'. We
	209	base our calculation on the amount of stack space reserved by the
	210	first instruction of the signal trampoline. */
	211	insn = extract_unsigned_integer (buf, PPC_INSN_SIZE);
	212	sigcontext_offset = (0x10000 - (insn & 0x0000ffff)) + 8;
	213
18b2ae85	214	base = frame_unwind_register_unsigned (next_frame, SP_REGNUM);
0dbe1904	215	addr = base + sigcontext_offset + 2 * tdep->wordsize;
18b2ae85 MK	216	for (i = 0; i < ppc_num_gprs; i++, addr += tdep->wordsize)
	217	{
	218	int regnum = i + tdep->ppc_gp0_regnum;
0dbe1904	219	trad_frame_set_reg_addr (cache, regnum, addr);
18b2ae85	220	}
0dbe1904	221	trad_frame_set_reg_addr (cache, tdep->ppc_lr_regnum, addr);
18b2ae85	222	addr += tdep->wordsize;
0dbe1904	223	trad_frame_set_reg_addr (cache, tdep->ppc_cr_regnum, addr);
18b2ae85	224	addr += tdep->wordsize;
0dbe1904	225	trad_frame_set_reg_addr (cache, tdep->ppc_xer_regnum, addr);
18b2ae85	226	addr += tdep->wordsize;
0dbe1904	227	trad_frame_set_reg_addr (cache, tdep->ppc_ctr_regnum, addr);
18b2ae85	228	addr += tdep->wordsize;
0dbe1904	229	trad_frame_set_reg_addr (cache, PC_REGNUM, addr); /* SRR0? */
18b2ae85 MK	230	addr += tdep->wordsize;
	231
	232	/* Construct the frame ID using the function start. */
0dbe1904 MK	233	trad_frame_set_id (cache, frame_id_build (base, func));
	234
	235	return cache;
18b2ae85 MK	236	}
18b2ae85 MK	237
0dbe1904 MK	238	static void
	239	ppcobsd_sigtramp_frame_this_id (struct frame_info *next_frame,
	240	void *this_cache, struct frame_id this_id)
	241	{
	242	struct trad_frame_cache *cache =
	243	ppcobsd_sigtramp_frame_cache (next_frame, this_cache);
	244
	245	trad_frame_get_id (cache, this_id);
	246	}
	247
	248	static void
	249	ppcobsd_sigtramp_frame_prev_register (struct frame_info *next_frame,
	250	void **this_cache, int regnum,
	251	int optimizedp, enum lval_type lvalp,
	252	CORE_ADDR addrp, int realnump,
	253	gdb_byte *valuep)
18b2ae85	254	{
0dbe1904 MK	255	struct trad_frame_cache *cache =
	256	ppcobsd_sigtramp_frame_cache (next_frame, this_cache);
	257
	258	trad_frame_get_register (cache, next_frame, regnum,
	259	optimizedp, lvalp, addrp, realnump, valuep);
	260	}
	261
	262	static const struct frame_unwind ppcobsd_sigtramp_frame_unwind = {
18b2ae85	263	SIGTRAMP_FRAME,
0dbe1904 MK	264	ppcobsd_sigtramp_frame_this_id,
0dbe1904 MK	265	ppcobsd_sigtramp_frame_prev_register
18b2ae85	266	};
0dbe1904 MK	267
	268	static const struct frame_unwind *
	269	ppcobsd_sigtramp_frame_sniffer (struct frame_info *next_frame)
	270	{
	271	if (ppcobsd_sigtramp_p (next_frame))
	272	return &ppcobsd_sigtramp_frame_unwind;
	273
	274	return NULL;
	275	}
18b2ae85	276	\f
5d6210f0	277
d195bc9f MK	278	static void
	279	ppcobsd_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
	280	{
5a49dfd0 MK	281	/* OpenBSD doesn't support the 128-bit `long double' from the psABI. */
	282	set_gdbarch_long_double_bit (gdbarch, 64);
	283	set_gdbarch_long_double_format (gdbarch, &floatformat_ieee_double_big);
	284
a86c5ab2 MK	285	/* OpenBSD currently uses a broken GCC. */
	286	set_gdbarch_return_value (gdbarch, ppc_sysv_abi_broken_return_value);
	287
d195bc9f	288	/* OpenBSD uses SVR4-style shared libraries. */
d195bc9f MK	289	set_solib_svr4_fetch_link_map_offsets
	290	(gdbarch, svr4_ilp32_fetch_link_map_offsets);
	291
	292	set_gdbarch_regset_from_core_section
	293	(gdbarch, ppcobsd_regset_from_core_section);
18b2ae85	294
0dbe1904	295	frame_unwind_append_sniffer (gdbarch, ppcobsd_sigtramp_frame_sniffer);
d195bc9f MK	296	}
	297	\f
	298
	299	/* OpenBSD uses uses the traditional NetBSD core file format, even for
	300	ports that use ELF. */
	301	#define GDB_OSABI_NETBSD_CORE GDB_OSABI_OPENBSD_ELF
	302
	303	static enum gdb_osabi
	304	ppcobsd_core_osabi_sniffer (bfd *abfd)
	305	{
	306	if (strcmp (bfd_get_target (abfd), "netbsd-core") == 0)
	307	return GDB_OSABI_NETBSD_CORE;
	308
	309	return GDB_OSABI_UNKNOWN;
	310	}
	311	\f
	312
	313	/* Provide a prototype to silence -Wmissing-prototypes. */
	314	void _initialize_ppcobsd_tdep (void);
	315
	316	void
	317	_initialize_ppcobsd_tdep (void)
	318	{
	319	/* BFD doesn't set a flavour for NetBSD style a.out core files. */
	320	gdbarch_register_osabi_sniffer (bfd_arch_powerpc, bfd_target_unknown_flavour,
	321	ppcobsd_core_osabi_sniffer);
	322
5d6210f0 MK	323	gdbarch_register_osabi (bfd_arch_rs6000, 0, GDB_OSABI_OPENBSD_ELF,
5d6210f0 MK	324	ppcobsd_init_abi);
d195bc9f MK	325	gdbarch_register_osabi (bfd_arch_powerpc, 0, GDB_OSABI_OPENBSD_ELF,
	326	ppcobsd_init_abi);
	327
	328	/* Avoid initializing the register offsets again if they were
	329	already initailized by ppcobsd-nat.c. */
	330	if (ppcobsd_reg_offsets.pc_offset == 0)
	331	{
	332	/* General-purpose registers. */
	333	ppcobsd_reg_offsets.r0_offset = 0;
	334	ppcobsd_reg_offsets.pc_offset = 384;
	335	ppcobsd_reg_offsets.ps_offset = 388;
	336	ppcobsd_reg_offsets.cr_offset = 392;
	337	ppcobsd_reg_offsets.lr_offset = 396;
	338	ppcobsd_reg_offsets.ctr_offset = 400;
	339	ppcobsd_reg_offsets.xer_offset = 404;
	340	ppcobsd_reg_offsets.mq_offset = 408;
	341
	342	/* Floating-point registers. */
	343	ppcobsd_reg_offsets.f0_offset = 128;
	344	ppcobsd_reg_offsets.fpscr_offset = -1;
	345
	346	/* AltiVec registers. */
	347	ppcobsd_reg_offsets.vr0_offset = 0;
	348	ppcobsd_reg_offsets.vscr_offset = 512;
	349	ppcobsd_reg_offsets.vrsave_offset = 520;
	350	}
8599da2d MK	351
	352	if (ppcobsd_fpreg_offsets.fpscr_offset == 0)
	353	{
	354	/* Floating-point registers. */
	355	ppcobsd_reg_offsets.f0_offset = 0;
	356	ppcobsd_reg_offsets.fpscr_offset = 256;
	357	}
d195bc9f	358	}