From 3379287ac9a887aa3c8e2ffd697816c3aff32ef0 Mon Sep 17 00:00:00 2001 From: Jason Thorpe Date: Sun, 21 Apr 2002 21:07:58 +0000 Subject: [PATCH] * 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. --- gdb/ChangeLog | 7 +++ gdb/alpha-linux-tdep.c | 98 +++++++++++++++++++++++++++++++++ gdb/alpha-tdep.c | 70 ----------------------- gdb/config/alpha/alpha-linux.mt | 2 +- 4 files changed, 106 insertions(+), 71 deletions(-) create mode 100644 gdb/alpha-linux-tdep.c diff --git a/gdb/ChangeLog b/gdb/ChangeLog index f6fd36b180a..b6804654a6e 100644 --- a/gdb/ChangeLog +++ b/gdb/ChangeLog @@ -1,3 +1,10 @@ +2002-04-21 Jason Thorpe + + * 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 * config/alpha/tm-alpha.h: Move alpha_software_single_step diff --git a/gdb/alpha-linux-tdep.c b/gdb/alpha-linux-tdep.c new file mode 100644 index 00000000000..cb4e9c7ee79 --- /dev/null +++ b/gdb/alpha-linux-tdep.c @@ -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); +} diff --git a/gdb/alpha-tdep.c b/gdb/alpha-tdep.c index 4f892371544..537ba920fcb 100644 --- a/gdb/alpha-tdep.c +++ b/gdb/alpha-tdep.c @@ -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 diff --git a/gdb/config/alpha/alpha-linux.mt b/gdb/config/alpha/alpha-linux.mt index dd1c8e2c18e..25538b34589 100644 --- a/gdb/config/alpha/alpha-linux.mt +++ b/gdb/config/alpha/alpha-linux.mt @@ -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 -- 2.30.2