6ea0ec3fe4
(alphaobsd_init_abi): Set skip_solib_resolver. * Makefile.in (alphaobsd-tdep.o): Update dependencies. * config/alpha/obsd.mt (TDEPFILES): Add obsd-tdep.o.
138 lines
4.0 KiB
C
138 lines
4.0 KiB
C
/* Target-dependent code for OpenBSD/alpha.
|
||
|
||
Copyright (C) 2006 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 "frame.h"
|
||
#include "gdbcore.h"
|
||
#include "osabi.h"
|
||
|
||
#include "obsd-tdep.h"
|
||
#include "alpha-tdep.h"
|
||
#include "alphabsd-tdep.h"
|
||
#include "solib-svr4.h"
|
||
|
||
/* Signal trampolines. */
|
||
|
||
/* The OpenBSD kernel maps the signal trampoline at some random
|
||
location in user space, which means that the traditional BSD way of
|
||
detecting it won't work.
|
||
|
||
The signal trampoline will be mapped at an address that is page
|
||
aligned. We recognize the signal trampoline by looking for the
|
||
sigreturn system call. */
|
||
|
||
static const int alphaobsd_page_size = 8192;
|
||
|
||
static LONGEST
|
||
alphaobsd_sigtramp_offset (CORE_ADDR pc)
|
||
{
|
||
return (pc & (alphaobsd_page_size - 1));
|
||
}
|
||
|
||
static int
|
||
alphaobsd_pc_in_sigtramp (CORE_ADDR pc, char *name)
|
||
{
|
||
CORE_ADDR start_pc = (pc & ~(alphaobsd_page_size - 1));
|
||
unsigned insn;
|
||
|
||
if (name)
|
||
return 0;
|
||
|
||
/* Check for "". */
|
||
insn = alpha_read_insn (start_pc + 5 * ALPHA_INSN_SIZE);
|
||
if (insn != 0x201f0067)
|
||
return 0;
|
||
|
||
/* Check for "". */
|
||
insn = alpha_read_insn (start_pc + 6 * ALPHA_INSN_SIZE);
|
||
if (insn != 0x00000083)
|
||
return 0;
|
||
|
||
return 1;
|
||
}
|
||
|
||
static CORE_ADDR
|
||
alphaobsd_sigcontext_addr (struct frame_info *next_frame)
|
||
{
|
||
CORE_ADDR pc = frame_pc_unwind (next_frame);
|
||
|
||
if (alphaobsd_sigtramp_offset (pc) < 3 * ALPHA_INSN_SIZE)
|
||
{
|
||
/* On entry, a pointer the `struct sigcontext' is passed in %a2. */
|
||
return frame_unwind_register_unsigned (next_frame, ALPHA_A0_REGNUM + 2);
|
||
}
|
||
else if (alphaobsd_sigtramp_offset (pc) < 4 * ALPHA_INSN_SIZE)
|
||
{
|
||
/* It is stored on the stack Before calling the signal handler. */
|
||
CORE_ADDR sp;
|
||
sp = frame_unwind_register_unsigned (next_frame, ALPHA_SP_REGNUM);
|
||
return get_frame_memory_unsigned (next_frame, sp, 8);
|
||
}
|
||
else
|
||
{
|
||
/* It is reloaded into %a0 for the sigreturn(2) call. */
|
||
return frame_unwind_register_unsigned (next_frame, ALPHA_A0_REGNUM);
|
||
}
|
||
}
|
||
|
||
|
||
static void
|
||
alphaobsd_init_abi(struct gdbarch_info info, struct gdbarch *gdbarch)
|
||
{
|
||
struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
|
||
|
||
/* Hook into the DWARF CFI frame unwinder. */
|
||
alpha_dwarf2_init_abi (info, gdbarch);
|
||
|
||
/* Hook into the MDEBUG frame unwinder. */
|
||
alpha_mdebug_init_abi (info, gdbarch);
|
||
|
||
/* OpenBSD/alpha 3.0 and earlier does not provide single step
|
||
support via ptrace(2); use software single-stepping for now. */
|
||
set_gdbarch_software_single_step (gdbarch, alpha_software_single_step);
|
||
|
||
/* OpenBSD/alpha has SVR4-style shared libraries. */
|
||
set_solib_svr4_fetch_link_map_offsets
|
||
(gdbarch, svr4_lp64_fetch_link_map_offsets);
|
||
set_gdbarch_skip_solib_resolver (gdbarch, obsd_skip_solib_resolver);
|
||
|
||
tdep->dynamic_sigtramp_offset = alphaobsd_sigtramp_offset;
|
||
tdep->pc_in_sigtramp = alphaobsd_pc_in_sigtramp;
|
||
tdep->sigcontext_addr = alphaobsd_sigcontext_addr;
|
||
|
||
tdep->jb_pc = 2;
|
||
tdep->jb_elt_size = 8;
|
||
|
||
set_gdbarch_regset_from_core_section
|
||
(gdbarch, alphanbsd_regset_from_core_section);
|
||
}
|
||
|
||
|
||
/* Provide a prototype to silence -Wmissing-prototypes. */
|
||
void _initialize_alphaobsd_tdep (void);
|
||
|
||
void
|
||
_initialize_alphaobsd_tdep (void)
|
||
{
|
||
gdbarch_register_osabi (bfd_arch_alpha, 0, GDB_OSABI_OPENBSD_ELF,
|
||
alphaobsd_init_abi);
|
||
}
|