[deliverable/binutils-gdb.git] / gdb / i386fbsd-tdep.c

/* Target-dependent code for FreeBSD/i386.

   Copyright (C) 2003-2015 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 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 "arch-utils.h"
#include "gdbcore.h"
#include "osabi.h"
#include "regcache.h"

#include "i386-tdep.h"
#include "i387-tdep.h"
#include "bsd-uthread.h"
#include "fbsd-tdep.h"
#include "solib-svr4.h"

/* Support for signal handlers.  */

/* Return whether THIS_FRAME corresponds to a FreeBSD sigtramp
   routine.  */

/* FreeBSD/i386 supports three different signal trampolines, one for
   versions before 4.0, a second for 4.x, and a third for 5.0 and
   later.  To complicate matters, FreeBSD/i386 binaries running under
   an amd64 kernel use a different set of trampolines.  These
   trampolines differ from the i386 kernel trampolines in that they
   omit a middle section that conditionally restores %gs.  */

static const gdb_byte i386fbsd_sigtramp_start[] =
{
  0x8d, 0x44, 0x24, 0x20,       /* lea     SIGF_UC(%esp),%eax */
  0x50				/* pushl   %eax */
};

static const gdb_byte i386fbsd_sigtramp_middle[] =
{
  0xf7, 0x40, 0x54, 0x00, 0x00, 0x02, 0x00,
				/* testl   $PSL_VM,UC_EFLAGS(%eax) */
  0x75, 0x03,			/* jne	   +3 */
  0x8e, 0x68, 0x14		/* mov	   UC_GS(%eax),%gs */
};

static const gdb_byte i386fbsd_sigtramp_end[] =
{
  0xb8, 0xa1, 0x01, 0x00, 0x00, /* movl   $SYS_sigreturn,%eax */
  0x50,			/* pushl   %eax */
  0xcd, 0x80			/* int	   $0x80 */
};

static const gdb_byte i386fbsd_freebsd4_sigtramp_start[] =
{
  0x8d, 0x44, 0x24, 0x14,	/* lea	   SIGF_UC4(%esp),%eax */
  0x50				/* pushl   %eax */
};

static const gdb_byte i386fbsd_freebsd4_sigtramp_middle[] =
{
  0xf7, 0x40, 0x54, 0x00, 0x00, 0x02, 0x00,
				/* testl   $PSL_VM,UC4_EFLAGS(%eax) */
  0x75, 0x03,			/* jne	   +3 */
  0x8e, 0x68, 0x14		/* mov	   UC4_GS(%eax),%gs */
};

static const gdb_byte i386fbsd_freebsd4_sigtramp_end[] =
{
  0xb8, 0x58, 0x01, 0x00, 0x00, /* movl    $344,%eax */
  0x50,			/* pushl   %eax */
  0xcd, 0x80			/* int	   $0x80 */
};

static const gdb_byte i386fbsd_osigtramp_start[] =
{
  0x8d, 0x44, 0x24, 0x14,	/* lea	   SIGF_SC(%esp),%eax */
  0x50				/* pushl   %eax */
};

static const gdb_byte i386fbsd_osigtramp_middle[] =
{
  0xf7, 0x40, 0x18, 0x00, 0x00, 0x02, 0x00,
				/* testl   $PSL_VM,SC_PS(%eax) */
  0x75, 0x03,			/* jne	   +3 */
  0x8e, 0x68, 0x44		/* mov	   SC_GS(%eax),%gs */
};

static const gdb_byte i386fbsd_osigtramp_end[] =
{
  0xb8, 0x67, 0x00, 0x00, 0x00, /* movl    $103,%eax */
  0x50,			/* pushl   %eax */
  0xcd, 0x80			/* int	   $0x80 */
};

/* The three different trampolines are all the same size.  */
gdb_static_assert (sizeof i386fbsd_sigtramp_start
		   == sizeof i386fbsd_freebsd4_sigtramp_start);
gdb_static_assert (sizeof i386fbsd_sigtramp_start
		   == sizeof i386fbsd_osigtramp_start);
gdb_static_assert (sizeof i386fbsd_sigtramp_middle
		   == sizeof i386fbsd_freebsd4_sigtramp_middle);
gdb_static_assert (sizeof i386fbsd_sigtramp_middle
		   == sizeof i386fbsd_osigtramp_middle);
gdb_static_assert (sizeof i386fbsd_sigtramp_end
		   == sizeof i386fbsd_freebsd4_sigtramp_end);
gdb_static_assert (sizeof i386fbsd_sigtramp_end
		   == sizeof i386fbsd_osigtramp_end);

/* We assume that the middle is the largest chunk below.  */
gdb_static_assert (sizeof i386fbsd_sigtramp_middle
		   > sizeof i386fbsd_sigtramp_start);
gdb_static_assert (sizeof i386fbsd_sigtramp_middle
		   > sizeof i386fbsd_sigtramp_end);

static int
i386fbsd_sigtramp_p (struct frame_info *this_frame)
{
  CORE_ADDR pc = get_frame_pc (this_frame);
  gdb_byte buf[sizeof i386fbsd_sigtramp_middle];
  const gdb_byte *middle, *end;

  /* Look for a matching start.  */
  if (!safe_frame_unwind_memory (this_frame, pc, buf,
				 sizeof i386fbsd_sigtramp_start))
    return 0;
  if (memcmp (buf, i386fbsd_sigtramp_start, sizeof i386fbsd_sigtramp_start)
      == 0)
    {
      middle = i386fbsd_sigtramp_middle;
      end = i386fbsd_sigtramp_end;
    }
  else if (memcmp (buf, i386fbsd_freebsd4_sigtramp_start,
		   sizeof i386fbsd_freebsd4_sigtramp_start) == 0)
    {
      middle = i386fbsd_freebsd4_sigtramp_middle;
      end = i386fbsd_freebsd4_sigtramp_end;
    }
  else if (memcmp (buf, i386fbsd_osigtramp_start,
		   sizeof i386fbsd_osigtramp_start) == 0)
    {
      middle = i386fbsd_osigtramp_middle;
      end = i386fbsd_osigtramp_end;
    }
  else
    return 0;

  /* Since the end is shorter than the middle, check for a matching end
     next.  */
  pc += sizeof i386fbsd_sigtramp_start;
  if (!safe_frame_unwind_memory (this_frame, pc, buf,
				 sizeof i386fbsd_sigtramp_end))
    return 0;
  if (memcmp (buf, end, sizeof i386fbsd_sigtramp_end) == 0)
    return 1;

  /* If the end didn't match, check for a matching middle.  */
  if (!safe_frame_unwind_memory (this_frame, pc, buf,
				 sizeof i386fbsd_sigtramp_middle))
    return 0;
  if (memcmp (buf, middle, sizeof i386fbsd_sigtramp_middle) != 0)
    return 0;

  /* The middle matched, check for a matching end.  */
  pc += sizeof i386fbsd_sigtramp_middle;
  if (!safe_frame_unwind_memory (this_frame, pc, buf,
				 sizeof i386fbsd_sigtramp_end))
    return 0;
  if (memcmp (buf, end, sizeof i386fbsd_sigtramp_end) != 0)
    return 0;

  return 1;
}

/* FreeBSD 3.0-RELEASE or later.  */

/* From <machine/reg.h>.  */
static int i386fbsd_r_reg_offset[] =
{
  9 * 4, 8 * 4, 7 * 4, 6 * 4,	/* %eax, %ecx, %edx, %ebx */
  15 * 4, 4 * 4,		/* %esp, %ebp */
  3 * 4, 2 * 4,			/* %esi, %edi */
  12 * 4, 14 * 4,		/* %eip, %eflags */
  13 * 4, 16 * 4,		/* %cs, %ss */
  1 * 4, 0 * 4, -1, -1		/* %ds, %es, %fs, %gs */
};

/* Sigtramp routine location.  */
CORE_ADDR i386fbsd_sigtramp_start_addr;
CORE_ADDR i386fbsd_sigtramp_end_addr;

/* From <machine/signal.h>.  */
int i386fbsd_sc_reg_offset[] =
{
  8 + 14 * 4,			/* %eax */
  8 + 13 * 4,			/* %ecx */
  8 + 12 * 4,			/* %edx */
  8 + 11 * 4,			/* %ebx */
  8 + 0 * 4,                    /* %esp */
  8 + 1 * 4,                    /* %ebp */
  8 + 10 * 4,                   /* %esi */
  8 + 9 * 4,                    /* %edi */
  8 + 3 * 4,                    /* %eip */
  8 + 4 * 4,                    /* %eflags */
  8 + 7 * 4,                    /* %cs */
  8 + 8 * 4,                    /* %ss */
  8 + 6 * 4,                    /* %ds */
  8 + 5 * 4,                    /* %es */
  8 + 15 * 4,			/* %fs */
  8 + 16 * 4			/* %gs */
};

/* From /usr/src/lib/libc/i386/gen/_setjmp.S.  */
static int i386fbsd_jmp_buf_reg_offset[] =
{
  -1,				/* %eax */
  -1,				/* %ecx */
  -1,				/* %edx */
  1 * 4,			/* %ebx */
  2 * 4,			/* %esp */
  3 * 4,			/* %ebp */
  4 * 4,			/* %esi */
  5 * 4,			/* %edi */
  0 * 4				/* %eip */
};

static void
i386fbsd_supply_uthread (struct regcache *regcache,
			 int regnum, CORE_ADDR addr)
{
  gdb_byte buf[4];
  int i;

  gdb_assert (regnum >= -1);

  for (i = 0; i < ARRAY_SIZE (i386fbsd_jmp_buf_reg_offset); i++)
    {
      if (i386fbsd_jmp_buf_reg_offset[i] != -1
	  && (regnum == -1 || regnum == i))
	{
	  read_memory (addr + i386fbsd_jmp_buf_reg_offset[i], buf, 4);
	  regcache_raw_supply (regcache, i, buf);
	}
    }
}

static void
i386fbsd_collect_uthread (const struct regcache *regcache,
			  int regnum, CORE_ADDR addr)
{
  gdb_byte buf[4];
  int i;

  gdb_assert (regnum >= -1);

  for (i = 0; i < ARRAY_SIZE (i386fbsd_jmp_buf_reg_offset); i++)
    {
      if (i386fbsd_jmp_buf_reg_offset[i] != -1
	  && (regnum == -1 || regnum == i))
	{
	  regcache_raw_collect (regcache, i, buf);
	  write_memory (addr + i386fbsd_jmp_buf_reg_offset[i], buf, 4);
	}
    }
}

static void
i386fbsdaout_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
{
  struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);

  /* Obviously FreeBSD is BSD-based.  */
  i386bsd_init_abi (info, gdbarch);

  /* FreeBSD has a different `struct reg', and reserves some space for
     its FPU emulator in `struct fpreg'.  */
  tdep->gregset_reg_offset = i386fbsd_r_reg_offset;
  tdep->gregset_num_regs = ARRAY_SIZE (i386fbsd_r_reg_offset);
  tdep->sizeof_gregset = 18 * 4;
  tdep->sizeof_fpregset = 176;

  /* FreeBSD uses -freg-struct-return by default.  */
  tdep->struct_return = reg_struct_return;

  tdep->sigtramp_p = i386fbsd_sigtramp_p;

  /* FreeBSD uses a different memory layout.  */
  tdep->sigtramp_start = i386fbsd_sigtramp_start_addr;
  tdep->sigtramp_end = i386fbsd_sigtramp_end_addr;

  /* FreeBSD has a more complete `struct sigcontext'.  */
  tdep->sc_reg_offset = i386fbsd_sc_reg_offset;
  tdep->sc_num_regs = ARRAY_SIZE (i386fbsd_sc_reg_offset);

  /* FreeBSD provides a user-level threads implementation.  */
  bsd_uthread_set_supply_uthread (gdbarch, i386fbsd_supply_uthread);
  bsd_uthread_set_collect_uthread (gdbarch, i386fbsd_collect_uthread);
}

static void
i386fbsd_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
{
  /* It's almost identical to FreeBSD a.out.  */
  i386fbsdaout_init_abi (info, gdbarch);

  /* Except that it uses ELF.  */
  i386_elf_init_abi (info, gdbarch);

  /* FreeBSD ELF uses SVR4-style shared libraries.  */
  set_solib_svr4_fetch_link_map_offsets
    (gdbarch, svr4_ilp32_fetch_link_map_offsets);
}

/* FreeBSD 4.0-RELEASE or later.  */

/* From <machine/reg.h>.  */
static int i386fbsd4_r_reg_offset[] =
{
  10 * 4, 9 * 4, 8 * 4, 7 * 4,	/* %eax, %ecx, %edx, %ebx */
  16 * 4, 5 * 4,		/* %esp, %ebp */
  4 * 4, 3 * 4,			/* %esi, %edi */
  13 * 4, 15 * 4,		/* %eip, %eflags */
  14 * 4, 17 * 4,		/* %cs, %ss */
  2 * 4, 1 * 4, 0 * 4, 18 * 4	/* %ds, %es, %fs, %gs */
};

/* From <machine/signal.h>.  */
int i386fbsd4_sc_reg_offset[] =
{
  20 + 11 * 4,			/* %eax */
  20 + 10 * 4,			/* %ecx */
  20 + 9 * 4,			/* %edx */
  20 + 8 * 4,			/* %ebx */
  20 + 17 * 4,			/* %esp */
  20 + 6 * 4,			/* %ebp */
  20 + 5 * 4,			/* %esi */
  20 + 4 * 4,			/* %edi */
  20 + 14 * 4,			/* %eip */
  20 + 16 * 4,			/* %eflags */
  20 + 15 * 4,			/* %cs */
  20 + 18 * 4,			/* %ss */
  20 + 3 * 4,			/* %ds */
  20 + 2 * 4,			/* %es */
  20 + 1 * 4,			/* %fs */
  20 + 0 * 4			/* %gs */
};

static void
i386fbsd4_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
{
  struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);

  /* Generic FreeBSD support. */
  fbsd_init_abi (info, gdbarch);

  /* Inherit stuff from older releases.  We assume that FreeBSD
     4.0-RELEASE always uses ELF.  */
  i386fbsd_init_abi (info, gdbarch);

  /* FreeBSD 4.0 introduced a new `struct reg'.  */
  tdep->gregset_reg_offset = i386fbsd4_r_reg_offset;
  tdep->gregset_num_regs = ARRAY_SIZE (i386fbsd4_r_reg_offset);
  tdep->sizeof_gregset = 19 * 4;

  /* FreeBSD 4.0 introduced a new `struct sigcontext'.  */
  tdep->sc_reg_offset = i386fbsd4_sc_reg_offset;
  tdep->sc_num_regs = ARRAY_SIZE (i386fbsd4_sc_reg_offset);
}

\f
/* Provide a prototype to silence -Wmissing-prototypes.  */
void _initialize_i386fbsd_tdep (void);

void
_initialize_i386fbsd_tdep (void)
{
  gdbarch_register_osabi (bfd_arch_i386, 0, GDB_OSABI_FREEBSD_AOUT,
			  i386fbsdaout_init_abi);
  gdbarch_register_osabi (bfd_arch_i386, 0, GDB_OSABI_FREEBSD_ELF,
			  i386fbsd4_init_abi);
}
Commit	Line	Data
	1	/* Target-dependent code for FreeBSD/i386.
	2
	3	Copyright (C) 2003-2015 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 "defs.h"
	21	#include "arch-utils.h"
	22	#include "gdbcore.h"
	23	#include "osabi.h"
	24	#include "regcache.h"
	25
	26	#include "i386-tdep.h"
	27	#include "i387-tdep.h"
	28	#include "bsd-uthread.h"
	29	#include "fbsd-tdep.h"
	30	#include "solib-svr4.h"
	31
	32	/* Support for signal handlers. */
	33
	34	/* Return whether THIS_FRAME corresponds to a FreeBSD sigtramp
	35	routine. */
	36
	37	/* FreeBSD/i386 supports three different signal trampolines, one for
	38	versions before 4.0, a second for 4.x, and a third for 5.0 and
	39	later. To complicate matters, FreeBSD/i386 binaries running under
	40	an amd64 kernel use a different set of trampolines. These
	41	trampolines differ from the i386 kernel trampolines in that they
	42	omit a middle section that conditionally restores %gs. */
	43
	44	static const gdb_byte i386fbsd_sigtramp_start[] =
	45	{
	46	0x8d, 0x44, 0x24, 0x20, /* lea SIGF_UC(%esp),%eax */
	47	0x50 /* pushl %eax */
	48	};
	49
	50	static const gdb_byte i386fbsd_sigtramp_middle[] =
	51	{
	52	0xf7, 0x40, 0x54, 0x00, 0x00, 0x02, 0x00,
	53	/* testl $PSL_VM,UC_EFLAGS(%eax) */
	54	0x75, 0x03, /* jne +3 */
	55	0x8e, 0x68, 0x14 /* mov UC_GS(%eax),%gs */
	56	};
	57
	58	static const gdb_byte i386fbsd_sigtramp_end[] =
	59	{
	60	0xb8, 0xa1, 0x01, 0x00, 0x00, /* movl $SYS_sigreturn,%eax */
	61	0x50, /* pushl %eax */
	62	0xcd, 0x80 /* int $0x80 */
	63	};
	64
	65	static const gdb_byte i386fbsd_freebsd4_sigtramp_start[] =
	66	{
	67	0x8d, 0x44, 0x24, 0x14, /* lea SIGF_UC4(%esp),%eax */
	68	0x50 /* pushl %eax */
	69	};
	70
	71	static const gdb_byte i386fbsd_freebsd4_sigtramp_middle[] =
	72	{
	73	0xf7, 0x40, 0x54, 0x00, 0x00, 0x02, 0x00,
	74	/* testl $PSL_VM,UC4_EFLAGS(%eax) */
	75	0x75, 0x03, /* jne +3 */
	76	0x8e, 0x68, 0x14 /* mov UC4_GS(%eax),%gs */
	77	};
	78
	79	static const gdb_byte i386fbsd_freebsd4_sigtramp_end[] =
	80	{
	81	0xb8, 0x58, 0x01, 0x00, 0x00, /* movl $344,%eax */
	82	0x50, /* pushl %eax */
	83	0xcd, 0x80 /* int $0x80 */
	84	};
	85
	86	static const gdb_byte i386fbsd_osigtramp_start[] =
	87	{
	88	0x8d, 0x44, 0x24, 0x14, /* lea SIGF_SC(%esp),%eax */
	89	0x50 /* pushl %eax */
	90	};
	91
	92	static const gdb_byte i386fbsd_osigtramp_middle[] =
	93	{
	94	0xf7, 0x40, 0x18, 0x00, 0x00, 0x02, 0x00,
	95	/* testl $PSL_VM,SC_PS(%eax) */
	96	0x75, 0x03, /* jne +3 */
	97	0x8e, 0x68, 0x44 /* mov SC_GS(%eax),%gs */
	98	};
	99
	100	static const gdb_byte i386fbsd_osigtramp_end[] =
	101	{
	102	0xb8, 0x67, 0x00, 0x00, 0x00, /* movl $103,%eax */
	103	0x50, /* pushl %eax */
	104	0xcd, 0x80 /* int $0x80 */
	105	};
	106
	107	/* The three different trampolines are all the same size. */
	108	gdb_static_assert (sizeof i386fbsd_sigtramp_start
	109	== sizeof i386fbsd_freebsd4_sigtramp_start);
	110	gdb_static_assert (sizeof i386fbsd_sigtramp_start
	111	== sizeof i386fbsd_osigtramp_start);
	112	gdb_static_assert (sizeof i386fbsd_sigtramp_middle
	113	== sizeof i386fbsd_freebsd4_sigtramp_middle);
	114	gdb_static_assert (sizeof i386fbsd_sigtramp_middle
	115	== sizeof i386fbsd_osigtramp_middle);
	116	gdb_static_assert (sizeof i386fbsd_sigtramp_end
	117	== sizeof i386fbsd_freebsd4_sigtramp_end);
	118	gdb_static_assert (sizeof i386fbsd_sigtramp_end
	119	== sizeof i386fbsd_osigtramp_end);
	120
	121	/* We assume that the middle is the largest chunk below. */
	122	gdb_static_assert (sizeof i386fbsd_sigtramp_middle
	123	> sizeof i386fbsd_sigtramp_start);
	124	gdb_static_assert (sizeof i386fbsd_sigtramp_middle
	125	> sizeof i386fbsd_sigtramp_end);
	126
	127	static int
	128	i386fbsd_sigtramp_p (struct frame_info *this_frame)
	129	{
	130	CORE_ADDR pc = get_frame_pc (this_frame);
	131	gdb_byte buf[sizeof i386fbsd_sigtramp_middle];
	132	const gdb_byte middle, end;
	133
	134	/* Look for a matching start. */
	135	if (!safe_frame_unwind_memory (this_frame, pc, buf,
	136	sizeof i386fbsd_sigtramp_start))
	137	return 0;
	138	if (memcmp (buf, i386fbsd_sigtramp_start, sizeof i386fbsd_sigtramp_start)
	139	== 0)
	140	{
	141	middle = i386fbsd_sigtramp_middle;
	142	end = i386fbsd_sigtramp_end;
	143	}
	144	else if (memcmp (buf, i386fbsd_freebsd4_sigtramp_start,
	145	sizeof i386fbsd_freebsd4_sigtramp_start) == 0)
	146	{
	147	middle = i386fbsd_freebsd4_sigtramp_middle;
	148	end = i386fbsd_freebsd4_sigtramp_end;
	149	}
	150	else if (memcmp (buf, i386fbsd_osigtramp_start,
	151	sizeof i386fbsd_osigtramp_start) == 0)
	152	{
	153	middle = i386fbsd_osigtramp_middle;
	154	end = i386fbsd_osigtramp_end;
	155	}
	156	else
	157	return 0;
	158
	159	/* Since the end is shorter than the middle, check for a matching end
	160	next. */
	161	pc += sizeof i386fbsd_sigtramp_start;
	162	if (!safe_frame_unwind_memory (this_frame, pc, buf,
	163	sizeof i386fbsd_sigtramp_end))
	164	return 0;
	165	if (memcmp (buf, end, sizeof i386fbsd_sigtramp_end) == 0)
	166	return 1;
	167
	168	/* If the end didn't match, check for a matching middle. */
	169	if (!safe_frame_unwind_memory (this_frame, pc, buf,
	170	sizeof i386fbsd_sigtramp_middle))
	171	return 0;
	172	if (memcmp (buf, middle, sizeof i386fbsd_sigtramp_middle) != 0)
	173	return 0;
	174
	175	/* The middle matched, check for a matching end. */
	176	pc += sizeof i386fbsd_sigtramp_middle;
	177	if (!safe_frame_unwind_memory (this_frame, pc, buf,
	178	sizeof i386fbsd_sigtramp_end))
	179	return 0;
	180	if (memcmp (buf, end, sizeof i386fbsd_sigtramp_end) != 0)
	181	return 0;
	182
	183	return 1;
	184	}
	185
	186	/* FreeBSD 3.0-RELEASE or later. */
	187
	188	/* From <machine/reg.h>. */
	189	static int i386fbsd_r_reg_offset[] =
	190	{
	191	9 * 4, 8 * 4, 7 * 4, 6 * 4, /* %eax, %ecx, %edx, %ebx */
	192	15 * 4, 4 * 4, /* %esp, %ebp */
	193	3 * 4, 2 * 4, /* %esi, %edi */
	194	12 * 4, 14 * 4, /* %eip, %eflags */
	195	13 * 4, 16 * 4, /* %cs, %ss */
	196	1 * 4, 0 * 4, -1, -1 /* %ds, %es, %fs, %gs */
	197	};
	198
	199	/* Sigtramp routine location. */
	200	CORE_ADDR i386fbsd_sigtramp_start_addr;
	201	CORE_ADDR i386fbsd_sigtramp_end_addr;
	202
	203	/* From <machine/signal.h>. */
	204	int i386fbsd_sc_reg_offset[] =
	205	{
	206	8 + 14 * 4, /* %eax */
	207	8 + 13 * 4, /* %ecx */
	208	8 + 12 * 4, /* %edx */
	209	8 + 11 * 4, /* %ebx */
	210	8 + 0 * 4, /* %esp */
	211	8 + 1 * 4, /* %ebp */
	212	8 + 10 * 4, /* %esi */
	213	8 + 9 * 4, /* %edi */
	214	8 + 3 * 4, /* %eip */
	215	8 + 4 * 4, /* %eflags */
	216	8 + 7 * 4, /* %cs */
	217	8 + 8 * 4, /* %ss */
	218	8 + 6 * 4, /* %ds */
	219	8 + 5 * 4, /* %es */
	220	8 + 15 * 4, /* %fs */
	221	8 + 16 * 4 /* %gs */
	222	};
	223
	224	/* From /usr/src/lib/libc/i386/gen/_setjmp.S. */
	225	static int i386fbsd_jmp_buf_reg_offset[] =
	226	{
	227	-1, /* %eax */
	228	-1, /* %ecx */
	229	-1, /* %edx */
	230	1 * 4, /* %ebx */
	231	2 * 4, /* %esp */
	232	3 * 4, /* %ebp */
	233	4 * 4, /* %esi */
	234	5 * 4, /* %edi */
	235	0 * 4 /* %eip */
	236	};
	237
	238	static void
	239	i386fbsd_supply_uthread (struct regcache *regcache,
	240	int regnum, CORE_ADDR addr)
	241	{
	242	gdb_byte buf[4];
	243	int i;
	244
	245	gdb_assert (regnum >= -1);
	246
	247	for (i = 0; i < ARRAY_SIZE (i386fbsd_jmp_buf_reg_offset); i++)
	248	{
	249	if (i386fbsd_jmp_buf_reg_offset[i] != -1
	250	&& (regnum == -1 \|\| regnum == i))
	251	{
	252	read_memory (addr + i386fbsd_jmp_buf_reg_offset[i], buf, 4);
	253	regcache_raw_supply (regcache, i, buf);
	254	}
	255	}
	256	}
	257
	258	static void
	259	i386fbsd_collect_uthread (const struct regcache *regcache,
	260	int regnum, CORE_ADDR addr)
	261	{
	262	gdb_byte buf[4];
	263	int i;
	264
	265	gdb_assert (regnum >= -1);
	266
	267	for (i = 0; i < ARRAY_SIZE (i386fbsd_jmp_buf_reg_offset); i++)
	268	{
	269	if (i386fbsd_jmp_buf_reg_offset[i] != -1
	270	&& (regnum == -1 \|\| regnum == i))
	271	{
	272	regcache_raw_collect (regcache, i, buf);
	273	write_memory (addr + i386fbsd_jmp_buf_reg_offset[i], buf, 4);
	274	}
	275	}
	276	}
	277
	278	static void
	279	i386fbsdaout_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
	280	{
	281	struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
	282
	283	/* Obviously FreeBSD is BSD-based. */
	284	i386bsd_init_abi (info, gdbarch);
	285
	286	/* FreeBSD has a different `struct reg', and reserves some space for
	287	its FPU emulator in `struct fpreg'. */
	288	tdep->gregset_reg_offset = i386fbsd_r_reg_offset;
	289	tdep->gregset_num_regs = ARRAY_SIZE (i386fbsd_r_reg_offset);
	290	tdep->sizeof_gregset = 18 * 4;
	291	tdep->sizeof_fpregset = 176;
	292
	293	/* FreeBSD uses -freg-struct-return by default. */
	294	tdep->struct_return = reg_struct_return;
	295
	296	tdep->sigtramp_p = i386fbsd_sigtramp_p;
	297
	298	/* FreeBSD uses a different memory layout. */
	299	tdep->sigtramp_start = i386fbsd_sigtramp_start_addr;
	300	tdep->sigtramp_end = i386fbsd_sigtramp_end_addr;
	301
	302	/* FreeBSD has a more complete `struct sigcontext'. */
	303	tdep->sc_reg_offset = i386fbsd_sc_reg_offset;
	304	tdep->sc_num_regs = ARRAY_SIZE (i386fbsd_sc_reg_offset);
	305
	306	/* FreeBSD provides a user-level threads implementation. */
	307	bsd_uthread_set_supply_uthread (gdbarch, i386fbsd_supply_uthread);
	308	bsd_uthread_set_collect_uthread (gdbarch, i386fbsd_collect_uthread);
	309	}
	310
	311	static void
	312	i386fbsd_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
	313	{
	314	/* It's almost identical to FreeBSD a.out. */
	315	i386fbsdaout_init_abi (info, gdbarch);
	316
	317	/* Except that it uses ELF. */
	318	i386_elf_init_abi (info, gdbarch);
	319
	320	/* FreeBSD ELF uses SVR4-style shared libraries. */
	321	set_solib_svr4_fetch_link_map_offsets
	322	(gdbarch, svr4_ilp32_fetch_link_map_offsets);
	323	}
	324
	325	/* FreeBSD 4.0-RELEASE or later. */
	326
	327	/* From <machine/reg.h>. */
	328	static int i386fbsd4_r_reg_offset[] =
	329	{
	330	10 * 4, 9 * 4, 8 * 4, 7 * 4, /* %eax, %ecx, %edx, %ebx */
	331	16 * 4, 5 * 4, /* %esp, %ebp */
	332	4 * 4, 3 * 4, /* %esi, %edi */
	333	13 * 4, 15 * 4, /* %eip, %eflags */
	334	14 * 4, 17 * 4, /* %cs, %ss */
	335	2 * 4, 1 * 4, 0 * 4, 18 * 4 /* %ds, %es, %fs, %gs */
	336	};
	337
	338	/* From <machine/signal.h>. */
	339	int i386fbsd4_sc_reg_offset[] =
	340	{
	341	20 + 11 * 4, /* %eax */
	342	20 + 10 * 4, /* %ecx */
	343	20 + 9 * 4, /* %edx */
	344	20 + 8 * 4, /* %ebx */
	345	20 + 17 * 4, /* %esp */
	346	20 + 6 * 4, /* %ebp */
	347	20 + 5 * 4, /* %esi */
	348	20 + 4 * 4, /* %edi */
	349	20 + 14 * 4, /* %eip */
	350	20 + 16 * 4, /* %eflags */
	351	20 + 15 * 4, /* %cs */
	352	20 + 18 * 4, /* %ss */
	353	20 + 3 * 4, /* %ds */
	354	20 + 2 * 4, /* %es */
	355	20 + 1 * 4, /* %fs */
	356	20 + 0 * 4 /* %gs */
	357	};
	358
	359	static void
	360	i386fbsd4_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
	361	{
	362	struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
	363
	364	/* Generic FreeBSD support. */
	365	fbsd_init_abi (info, gdbarch);
	366
	367	/* Inherit stuff from older releases. We assume that FreeBSD
	368	4.0-RELEASE always uses ELF. */
	369	i386fbsd_init_abi (info, gdbarch);
	370
	371	/* FreeBSD 4.0 introduced a new `struct reg'. */
	372	tdep->gregset_reg_offset = i386fbsd4_r_reg_offset;
	373	tdep->gregset_num_regs = ARRAY_SIZE (i386fbsd4_r_reg_offset);
	374	tdep->sizeof_gregset = 19 * 4;
	375
	376	/* FreeBSD 4.0 introduced a new `struct sigcontext'. */
	377	tdep->sc_reg_offset = i386fbsd4_sc_reg_offset;
	378	tdep->sc_num_regs = ARRAY_SIZE (i386fbsd4_sc_reg_offset);
	379	}
	380
	381	\f
	382	/* Provide a prototype to silence -Wmissing-prototypes. */
	383	void _initialize_i386fbsd_tdep (void);
	384
	385	void
	386	_initialize_i386fbsd_tdep (void)
	387	{
	388	gdbarch_register_osabi (bfd_arch_i386, 0, GDB_OSABI_FREEBSD_AOUT,
	389	i386fbsdaout_init_abi);
	390	gdbarch_register_osabi (bfd_arch_i386, 0, GDB_OSABI_FREEBSD_ELF,
	391	i386fbsd4_init_abi);
	392	}