* alpha-linux-tdep.c: New file. Move alpha_linux_sigtramp_offset

to here...
* alpha-tdep.c: ...from here.
* config/alpha/alpha-linux.mt (TDEPFILES): Add alpha-linux-tdep.o.
This commit is contained in:
Jason Thorpe 2002-04-21 21:07:58 +00:00
parent 4bcbd6cb5f
commit 3379287ac9
4 changed files with 106 additions and 71 deletions

View File

@ -1,3 +1,10 @@
2002-04-21 Jason Thorpe <thorpej@wasabisystems.com>
* alpha-linux-tdep.c: New file. Move alpha_linux_sigtramp_offset
to here...
* alpha-tdep.c: ...from here.
* config/alpha/alpha-linux.mt (TDEPFILES): Add alpha-linux-tdep.o.
2002-04-21 Jason Thorpe <thorpej@wasabisystems.com>
* config/alpha/tm-alpha.h: Move alpha_software_single_step

98
gdb/alpha-linux-tdep.c Normal file
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@ -0,0 +1,98 @@
/* Target-dependent code for GNU/Linux on Alpha.
Copyright 2002 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., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA. */
#include "defs.h"
#include "value.h"
#include "alpha-tdep.h"
/* Under GNU/Linux, signal handler invocations can be identified by the
designated code sequence that is used to return from a signal
handler. In particular, the return address of a signal handler
points to the following sequence (the first instruction is quadword
aligned):
bis $30,$30,$16
addq $31,0x67,$0
call_pal callsys
Each instruction has a unique encoding, so we simply attempt to
match the instruction the pc is pointing to with any of the above
instructions. If there is a hit, we know the offset to the start
of the designated sequence and can then check whether we really are
executing in a designated sequence. If not, -1 is returned,
otherwise the offset from the start of the desingated sequence is
returned.
There is a slight chance of false hits: code could jump into the
middle of the designated sequence, in which case there is no
guarantee that we are in the middle of a sigreturn syscall. Don't
think this will be a problem in praxis, though. */
long
alpha_linux_sigtramp_offset (CORE_ADDR pc)
{
unsigned int i[3], w;
long off;
if (read_memory_nobpt (pc, (char *) &w, 4) != 0)
return -1;
off = -1;
switch (w)
{
case 0x47de0410:
off = 0;
break; /* bis $30,$30,$16 */
case 0x43ecf400:
off = 4;
break; /* addq $31,0x67,$0 */
case 0x00000083:
off = 8;
break; /* call_pal callsys */
default:
return -1;
}
pc -= off;
if (pc & 0x7)
{
/* designated sequence is not quadword aligned */
return -1;
}
if (read_memory_nobpt (pc, (char *) i, sizeof (i)) != 0)
return -1;
if (i[0] == 0x47de0410 && i[1] == 0x43ecf400 && i[2] == 0x00000083)
return off;
return -1;
}
static void
alpha_linux_init_abi (struct gdbarch_info info,
struct gdbarch *gdbarch)
{
/* Place holder. */
}
void
_initialize_alpha_linux_tdep (void)
{
alpha_gdbarch_register_os_abi (ALPHA_ABI_LINUX, alpha_linux_init_abi);
}

View File

@ -201,76 +201,6 @@ alpha_osf_in_sigtramp (CORE_ADDR pc, char *func_name)
return (func_name != NULL && STREQ ("__sigtramp", func_name));
}
/* Under GNU/Linux, signal handler invocations can be identified by the
designated code sequence that is used to return from a signal
handler. In particular, the return address of a signal handler
points to the following sequence (the first instruction is quadword
aligned):
bis $30,$30,$16
addq $31,0x67,$0
call_pal callsys
Each instruction has a unique encoding, so we simply attempt to
match the instruction the pc is pointing to with any of the above
instructions. If there is a hit, we know the offset to the start
of the designated sequence and can then check whether we really are
executing in a designated sequence. If not, -1 is returned,
otherwise the offset from the start of the desingated sequence is
returned.
There is a slight chance of false hits: code could jump into the
middle of the designated sequence, in which case there is no
guarantee that we are in the middle of a sigreturn syscall. Don't
think this will be a problem in praxis, though.
*/
#ifndef TM_LINUXALPHA_H
/* HACK: Provide a prototype when compiling this file for non
linuxalpha targets. */
long alpha_linux_sigtramp_offset (CORE_ADDR pc);
#endif
long
alpha_linux_sigtramp_offset (CORE_ADDR pc)
{
unsigned int i[3], w;
long off;
if (read_memory_nobpt (pc, (char *) &w, 4) != 0)
return -1;
off = -1;
switch (w)
{
case 0x47de0410:
off = 0;
break; /* bis $30,$30,$16 */
case 0x43ecf400:
off = 4;
break; /* addq $31,0x67,$0 */
case 0x00000083:
off = 8;
break; /* call_pal callsys */
default:
return -1;
}
pc -= off;
if (pc & 0x7)
{
/* designated sequence is not quadword aligned */
return -1;
}
if (read_memory_nobpt (pc, (char *) i, sizeof (i)) != 0)
return -1;
if (i[0] == 0x47de0410 && i[1] == 0x43ecf400 && i[2] == 0x00000083)
return off;
return -1;
}
/* Under OSF/1, the __sigtramp routine is frameless and has a frame
size of zero, but we are able to backtrace through it. */
CORE_ADDR

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@ -1,3 +1,3 @@
# Target: Little-endian Alpha
TDEPFILES= alpha-tdep.o solib.o solib-svr4.o solib-legacy.o
TDEPFILES= alpha-tdep.o alpha-linux-tdep.o solib.o solib-svr4.o solib-legacy.o
TM_FILE= tm-alphalinux.h