383 lines
11 KiB
C
383 lines
11 KiB
C
/* Motorola m68k target-dependent support for GNU/Linux.
|
||
|
||
Copyright (C) 1996, 1998, 2000, 2001, 2002, 2003, 2004, 2007, 2008, 2009,
|
||
2010 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 "gdbcore.h"
|
||
#include "doublest.h"
|
||
#include "floatformat.h"
|
||
#include "frame.h"
|
||
#include "target.h"
|
||
#include "gdb_string.h"
|
||
#include "gdbtypes.h"
|
||
#include "osabi.h"
|
||
#include "regcache.h"
|
||
#include "objfiles.h"
|
||
#include "symtab.h"
|
||
#include "m68k-tdep.h"
|
||
#include "trad-frame.h"
|
||
#include "frame-unwind.h"
|
||
#include "glibc-tdep.h"
|
||
#include "solib-svr4.h"
|
||
#include "auxv.h"
|
||
#include "observer.h"
|
||
#include "elf/common.h"
|
||
|
||
/* Offsets (in target ints) into jmp_buf. */
|
||
|
||
#define M68K_LINUX_JB_ELEMENT_SIZE 4
|
||
#define M68K_LINUX_JB_PC 7
|
||
|
||
/* Check whether insn1 and insn2 are parts of a signal trampoline. */
|
||
|
||
#define IS_SIGTRAMP(insn1, insn2) \
|
||
(/* addaw #20,sp; moveq #119,d0; trap #0 */ \
|
||
(insn1 == 0xdefc0014 && insn2 == 0x70774e40) \
|
||
/* moveq #119,d0; trap #0 */ \
|
||
|| insn1 == 0x70774e40)
|
||
|
||
#define IS_RT_SIGTRAMP(insn1, insn2) \
|
||
(/* movel #173,d0; trap #0 */ \
|
||
(insn1 == 0x203c0000 && insn2 == 0x00ad4e40) \
|
||
/* moveq #82,d0; notb d0; trap #0 */ \
|
||
|| (insn1 == 0x70524600 && (insn2 >> 16) == 0x4e40))
|
||
|
||
/* Return non-zero if THIS_FRAME corresponds to a signal trampoline. For
|
||
the sake of m68k_linux_get_sigtramp_info we also distinguish between
|
||
non-RT and RT signal trampolines. */
|
||
|
||
static int
|
||
m68k_linux_pc_in_sigtramp (struct frame_info *this_frame)
|
||
{
|
||
struct gdbarch *gdbarch = get_frame_arch (this_frame);
|
||
enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
|
||
CORE_ADDR sp;
|
||
gdb_byte buf[12];
|
||
unsigned long insn0, insn1, insn2;
|
||
CORE_ADDR pc = get_frame_pc (this_frame);
|
||
|
||
if (!safe_frame_unwind_memory (this_frame, pc - 4, buf, sizeof (buf)))
|
||
return 0;
|
||
insn1 = extract_unsigned_integer (buf + 4, 4, byte_order);
|
||
insn2 = extract_unsigned_integer (buf + 8, 4, byte_order);
|
||
if (IS_SIGTRAMP (insn1, insn2))
|
||
return 1;
|
||
if (IS_RT_SIGTRAMP (insn1, insn2))
|
||
return 2;
|
||
|
||
insn0 = extract_unsigned_integer (buf, 4, byte_order);
|
||
if (IS_SIGTRAMP (insn0, insn1))
|
||
return 1;
|
||
if (IS_RT_SIGTRAMP (insn0, insn1))
|
||
return 2;
|
||
|
||
insn0 = ((insn0 << 16) & 0xffffffff) | (insn1 >> 16);
|
||
insn1 = ((insn1 << 16) & 0xffffffff) | (insn2 >> 16);
|
||
if (IS_SIGTRAMP (insn0, insn1))
|
||
return 1;
|
||
if (IS_RT_SIGTRAMP (insn0, insn1))
|
||
return 2;
|
||
|
||
return 0;
|
||
}
|
||
|
||
/* From <asm/sigcontext.h>. */
|
||
static int m68k_linux_sigcontext_reg_offset[M68K_NUM_REGS] =
|
||
{
|
||
2 * 4, /* %d0 */
|
||
3 * 4, /* %d1 */
|
||
-1, /* %d2 */
|
||
-1, /* %d3 */
|
||
-1, /* %d4 */
|
||
-1, /* %d5 */
|
||
-1, /* %d6 */
|
||
-1, /* %d7 */
|
||
4 * 4, /* %a0 */
|
||
5 * 4, /* %a1 */
|
||
-1, /* %a2 */
|
||
-1, /* %a3 */
|
||
-1, /* %a4 */
|
||
-1, /* %a5 */
|
||
-1, /* %fp */
|
||
1 * 4, /* %sp */
|
||
6 * 4, /* %sr */
|
||
6 * 4 + 2, /* %pc */
|
||
8 * 4, /* %fp0 */
|
||
11 * 4, /* %fp1 */
|
||
-1, /* %fp2 */
|
||
-1, /* %fp3 */
|
||
-1, /* %fp4 */
|
||
-1, /* %fp5 */
|
||
-1, /* %fp6 */
|
||
-1, /* %fp7 */
|
||
14 * 4, /* %fpcr */
|
||
15 * 4, /* %fpsr */
|
||
16 * 4 /* %fpiaddr */
|
||
};
|
||
|
||
static int m68k_uclinux_sigcontext_reg_offset[M68K_NUM_REGS] =
|
||
{
|
||
2 * 4, /* %d0 */
|
||
3 * 4, /* %d1 */
|
||
-1, /* %d2 */
|
||
-1, /* %d3 */
|
||
-1, /* %d4 */
|
||
-1, /* %d5 */
|
||
-1, /* %d6 */
|
||
-1, /* %d7 */
|
||
4 * 4, /* %a0 */
|
||
5 * 4, /* %a1 */
|
||
-1, /* %a2 */
|
||
-1, /* %a3 */
|
||
-1, /* %a4 */
|
||
6 * 4, /* %a5 */
|
||
-1, /* %fp */
|
||
1 * 4, /* %sp */
|
||
7 * 4, /* %sr */
|
||
7 * 4 + 2, /* %pc */
|
||
-1, /* %fp0 */
|
||
-1, /* %fp1 */
|
||
-1, /* %fp2 */
|
||
-1, /* %fp3 */
|
||
-1, /* %fp4 */
|
||
-1, /* %fp5 */
|
||
-1, /* %fp6 */
|
||
-1, /* %fp7 */
|
||
-1, /* %fpcr */
|
||
-1, /* %fpsr */
|
||
-1 /* %fpiaddr */
|
||
};
|
||
|
||
/* From <asm/ucontext.h>. */
|
||
static int m68k_linux_ucontext_reg_offset[M68K_NUM_REGS] =
|
||
{
|
||
6 * 4, /* %d0 */
|
||
7 * 4, /* %d1 */
|
||
8 * 4, /* %d2 */
|
||
9 * 4, /* %d3 */
|
||
10 * 4, /* %d4 */
|
||
11 * 4, /* %d5 */
|
||
12 * 4, /* %d6 */
|
||
13 * 4, /* %d7 */
|
||
14 * 4, /* %a0 */
|
||
15 * 4, /* %a1 */
|
||
16 * 4, /* %a2 */
|
||
17 * 4, /* %a3 */
|
||
18 * 4, /* %a4 */
|
||
19 * 4, /* %a5 */
|
||
20 * 4, /* %fp */
|
||
21 * 4, /* %sp */
|
||
23 * 4, /* %sr */
|
||
22 * 4, /* %pc */
|
||
27 * 4, /* %fp0 */
|
||
30 * 4, /* %fp1 */
|
||
33 * 4, /* %fp2 */
|
||
36 * 4, /* %fp3 */
|
||
39 * 4, /* %fp4 */
|
||
42 * 4, /* %fp5 */
|
||
45 * 4, /* %fp6 */
|
||
48 * 4, /* %fp7 */
|
||
24 * 4, /* %fpcr */
|
||
25 * 4, /* %fpsr */
|
||
26 * 4 /* %fpiaddr */
|
||
};
|
||
|
||
|
||
/* Get info about saved registers in sigtramp. */
|
||
|
||
struct m68k_linux_sigtramp_info
|
||
{
|
||
/* Address of sigcontext. */
|
||
CORE_ADDR sigcontext_addr;
|
||
|
||
/* Offset of registers in `struct sigcontext'. */
|
||
int *sc_reg_offset;
|
||
};
|
||
|
||
/* Nonzero if running on uClinux. */
|
||
static int target_is_uclinux;
|
||
|
||
static void
|
||
m68k_linux_inferior_created (struct target_ops *objfile, int from_tty)
|
||
{
|
||
/* Record that we will need to re-evaluate whether we are running on a
|
||
uClinux or normal GNU/Linux target (see m68k_linux_get_sigtramp_info). */
|
||
target_is_uclinux = -1;
|
||
}
|
||
|
||
static struct m68k_linux_sigtramp_info
|
||
m68k_linux_get_sigtramp_info (struct frame_info *this_frame)
|
||
{
|
||
struct gdbarch *gdbarch = get_frame_arch (this_frame);
|
||
enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
|
||
CORE_ADDR sp;
|
||
struct m68k_linux_sigtramp_info info;
|
||
|
||
if (target_is_uclinux == -1)
|
||
{
|
||
/* Determine whether we are running on a uClinux or normal GNU/Linux
|
||
target so we can use the correct sigcontext layouts. */
|
||
CORE_ADDR dummy;
|
||
|
||
target_is_uclinux
|
||
= (target_auxv_search (¤t_target, AT_NULL, &dummy) > 0
|
||
&& target_auxv_search (¤t_target, AT_PAGESZ, &dummy) == 0);
|
||
}
|
||
|
||
sp = get_frame_register_unsigned (this_frame, M68K_SP_REGNUM);
|
||
|
||
/* Get sigcontext address, it is the third parameter on the stack. */
|
||
info.sigcontext_addr = read_memory_unsigned_integer (sp + 8, 4, byte_order);
|
||
|
||
if (m68k_linux_pc_in_sigtramp (this_frame) == 2)
|
||
info.sc_reg_offset = m68k_linux_ucontext_reg_offset;
|
||
else
|
||
info.sc_reg_offset = (target_is_uclinux
|
||
? m68k_uclinux_sigcontext_reg_offset
|
||
: m68k_linux_sigcontext_reg_offset);
|
||
return info;
|
||
}
|
||
|
||
/* Signal trampolines. */
|
||
|
||
static struct trad_frame_cache *
|
||
m68k_linux_sigtramp_frame_cache (struct frame_info *this_frame,
|
||
void **this_cache)
|
||
{
|
||
struct frame_id this_id;
|
||
struct trad_frame_cache *cache;
|
||
struct gdbarch *gdbarch = get_frame_arch (this_frame);
|
||
struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
|
||
enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
|
||
struct m68k_linux_sigtramp_info info;
|
||
gdb_byte buf[4];
|
||
int i;
|
||
|
||
if (*this_cache)
|
||
return *this_cache;
|
||
|
||
cache = trad_frame_cache_zalloc (this_frame);
|
||
|
||
/* FIXME: cagney/2004-05-01: This is is long standing broken code.
|
||
The frame ID's code address should be the start-address of the
|
||
signal trampoline and not the current PC within that
|
||
trampoline. */
|
||
get_frame_register (this_frame, M68K_SP_REGNUM, buf);
|
||
/* See the end of m68k_push_dummy_call. */
|
||
this_id = frame_id_build (extract_unsigned_integer (buf, 4, byte_order)
|
||
- 4 + 8, get_frame_pc (this_frame));
|
||
trad_frame_set_id (cache, this_id);
|
||
|
||
info = m68k_linux_get_sigtramp_info (this_frame);
|
||
|
||
for (i = 0; i < M68K_NUM_REGS; i++)
|
||
if (info.sc_reg_offset[i] != -1)
|
||
trad_frame_set_reg_addr (cache, i,
|
||
info.sigcontext_addr + info.sc_reg_offset[i]);
|
||
|
||
*this_cache = cache;
|
||
return cache;
|
||
}
|
||
|
||
static void
|
||
m68k_linux_sigtramp_frame_this_id (struct frame_info *this_frame,
|
||
void **this_cache,
|
||
struct frame_id *this_id)
|
||
{
|
||
struct trad_frame_cache *cache =
|
||
m68k_linux_sigtramp_frame_cache (this_frame, this_cache);
|
||
trad_frame_get_id (cache, this_id);
|
||
}
|
||
|
||
static struct value *
|
||
m68k_linux_sigtramp_frame_prev_register (struct frame_info *this_frame,
|
||
void **this_cache,
|
||
int regnum)
|
||
{
|
||
/* Make sure we've initialized the cache. */
|
||
struct trad_frame_cache *cache =
|
||
m68k_linux_sigtramp_frame_cache (this_frame, this_cache);
|
||
return trad_frame_get_register (cache, this_frame, regnum);
|
||
}
|
||
|
||
static int
|
||
m68k_linux_sigtramp_frame_sniffer (const struct frame_unwind *self,
|
||
struct frame_info *this_frame,
|
||
void **this_prologue_cache)
|
||
{
|
||
return m68k_linux_pc_in_sigtramp (this_frame);
|
||
}
|
||
|
||
static const struct frame_unwind m68k_linux_sigtramp_frame_unwind =
|
||
{
|
||
SIGTRAMP_FRAME,
|
||
m68k_linux_sigtramp_frame_this_id,
|
||
m68k_linux_sigtramp_frame_prev_register,
|
||
NULL,
|
||
m68k_linux_sigtramp_frame_sniffer
|
||
};
|
||
|
||
static void
|
||
m68k_linux_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
|
||
{
|
||
struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
|
||
|
||
tdep->jb_pc = M68K_LINUX_JB_PC;
|
||
tdep->jb_elt_size = M68K_LINUX_JB_ELEMENT_SIZE;
|
||
|
||
/* GNU/Linux uses a calling convention that's similar to SVR4. It
|
||
returns integer values in %d0/%d1, pointer values in %a0 and
|
||
floating values in %fp0, just like SVR4, but uses %a1 to pass the
|
||
address to store a structure value. It also returns small
|
||
structures in registers instead of memory. */
|
||
m68k_svr4_init_abi (info, gdbarch);
|
||
tdep->struct_value_regnum = M68K_A1_REGNUM;
|
||
tdep->struct_return = reg_struct_return;
|
||
|
||
set_gdbarch_decr_pc_after_break (gdbarch, 2);
|
||
|
||
frame_unwind_append_unwinder (gdbarch, &m68k_linux_sigtramp_frame_unwind);
|
||
|
||
/* Shared library handling. */
|
||
|
||
/* GNU/Linux uses SVR4-style shared libraries. */
|
||
set_solib_svr4_fetch_link_map_offsets (gdbarch,
|
||
svr4_ilp32_fetch_link_map_offsets);
|
||
|
||
/* GNU/Linux uses the dynamic linker included in the GNU C Library. */
|
||
set_gdbarch_skip_solib_resolver (gdbarch, glibc_skip_solib_resolver);
|
||
|
||
set_gdbarch_skip_trampoline_code (gdbarch, find_solib_trampoline_target);
|
||
|
||
/* Enable TLS support. */
|
||
set_gdbarch_fetch_tls_load_module_address (gdbarch,
|
||
svr4_fetch_objfile_link_map);
|
||
}
|
||
|
||
/* Provide a prototype to silence -Wmissing-prototypes. */
|
||
extern initialize_file_ftype _initialize_m68k_linux_tdep;
|
||
|
||
void
|
||
_initialize_m68k_linux_tdep (void)
|
||
{
|
||
gdbarch_register_osabi (bfd_arch_m68k, 0, GDB_OSABI_LINUX,
|
||
m68k_linux_init_abi);
|
||
observer_attach_inferior_created (m68k_linux_inferior_created);
|
||
}
|