old-cross-binutils/gdb/m68klinux-tdep.c
Joel Brobecker a9762ec78a Switch the license of all .c files to GPLv3.
Switch the license of all .h files to GPLv3.
        Switch the license of all .cc files to GPLv3.
2007-08-23 18:08:50 +00:00

382 lines
10 KiB
C
Raw Blame History

This file contains invisible Unicode characters

This file contains invisible Unicode characters that are indistinguishable to humans but may be processed differently by a computer. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

/* Motorola m68k target-dependent support for GNU/Linux.
Copyright (C) 1996, 1998, 2000, 2001, 2002, 2003, 2004, 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 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 PC points into the 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 (CORE_ADDR pc, char *name)
{
CORE_ADDR sp;
char buf[12];
unsigned long insn0, insn1, insn2;
if (read_memory_nobpt (pc - 4, buf, sizeof (buf)))
return 0;
insn1 = extract_unsigned_integer (buf + 4, 4);
insn2 = extract_unsigned_integer (buf + 8, 4);
if (IS_SIGTRAMP (insn1, insn2))
return 1;
if (IS_RT_SIGTRAMP (insn1, insn2))
return 2;
insn0 = extract_unsigned_integer (buf, 4);
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 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 *next_frame)
{
CORE_ADDR sp;
char buf[4];
struct m68k_linux_sigtramp_info info;
if (target_is_uclinux == -1)
{
/* Determine whether we are running on a uClinux or normal Linux
target so we can use the correct sigcontext layouts. */
CORE_ADDR dummy;
target_is_uclinux
= target_auxv_search (&current_target, AT_NULL, &dummy) > 0
&& target_auxv_search (&current_target, AT_PAGESZ, &dummy) == 0;
}
frame_unwind_register (next_frame, M68K_SP_REGNUM, buf);
sp = extract_unsigned_integer (buf, 4);
/* Get sigcontext address, it is the third parameter on the stack. */
info.sigcontext_addr = read_memory_unsigned_integer (sp + 8, 4);
if (m68k_linux_pc_in_sigtramp (frame_pc_unwind (next_frame), 0) == 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 *next_frame,
void **this_cache)
{
struct frame_id this_id;
struct trad_frame_cache *cache;
struct gdbarch_tdep *tdep = gdbarch_tdep (current_gdbarch);
struct m68k_linux_sigtramp_info info;
char buf[4];
int i;
if (*this_cache)
return *this_cache;
cache = trad_frame_cache_zalloc (next_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. */
frame_unwind_register (next_frame, M68K_SP_REGNUM, buf);
/* See the end of m68k_push_dummy_call. */
this_id = frame_id_build (extract_unsigned_integer (buf, 4) - 4 + 8,
frame_pc_unwind (next_frame));
trad_frame_set_id (cache, this_id);
info = m68k_linux_get_sigtramp_info (next_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 *next_frame,
void **this_cache,
struct frame_id *this_id)
{
struct trad_frame_cache *cache =
m68k_linux_sigtramp_frame_cache (next_frame, this_cache);
trad_frame_get_id (cache, this_id);
}
static void
m68k_linux_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)
{
/* Make sure we've initialized the cache. */
struct trad_frame_cache *cache =
m68k_linux_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 m68k_linux_sigtramp_frame_unwind =
{
SIGTRAMP_FRAME,
m68k_linux_sigtramp_frame_this_id,
m68k_linux_sigtramp_frame_prev_register
};
static const struct frame_unwind *
m68k_linux_sigtramp_frame_sniffer (struct frame_info *next_frame)
{
CORE_ADDR pc = frame_pc_unwind (next_frame);
char *name;
find_pc_partial_function (pc, &name, NULL, NULL);
if (m68k_linux_pc_in_sigtramp (pc, name))
return &m68k_linux_sigtramp_frame_unwind;
return NULL;
}
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_sniffer (gdbarch, m68k_linux_sigtramp_frame_sniffer);
/* 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);
}
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);
}