2ea286498f
2012-05-24 Pedro Alves <palves@redhat.com> PR gdb/7205 Replace target_signal with gdb_signal throughout. gdb/gdbserver/ 2012-05-24 Pedro Alves <palves@redhat.com> PR gdb/7205 Replace target_signal with gdb_signal throughout. include/gdb/ 2012-05-24 Pedro Alves <palves@redhat.com> PR gdb/7205 Replace target_signal with gdb_signal throughout. sim/common/ 2012-05-24 Pedro Alves <palves@redhat.com> PR gdb/7205 Replace target_signal with gdb_signal throughout.
983 lines
33 KiB
C
983 lines
33 KiB
C
/* Target-dependent code for GNU/Linux i386.
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Copyright (C) 2000-2005, 2007-2012 Free Software Foundation, Inc.
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This file is part of GDB.
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This program is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 3 of the License, or
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(at your option) any later version.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this program. If not, see <http://www.gnu.org/licenses/>. */
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#include "defs.h"
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#include "gdbcore.h"
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#include "frame.h"
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#include "value.h"
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#include "regcache.h"
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#include "regset.h"
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#include "inferior.h"
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#include "osabi.h"
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#include "reggroups.h"
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#include "dwarf2-frame.h"
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#include "gdb_string.h"
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#include "i386-tdep.h"
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#include "i386-linux-tdep.h"
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#include "linux-tdep.h"
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#include "glibc-tdep.h"
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#include "solib-svr4.h"
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#include "symtab.h"
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#include "arch-utils.h"
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#include "xml-syscall.h"
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#include "i387-tdep.h"
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#include "i386-xstate.h"
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/* The syscall's XML filename for i386. */
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#define XML_SYSCALL_FILENAME_I386 "syscalls/i386-linux.xml"
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#include "record.h"
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#include "linux-record.h"
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#include <stdint.h>
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#include "features/i386/i386-linux.c"
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#include "features/i386/i386-mmx-linux.c"
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#include "features/i386/i386-avx-linux.c"
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/* Supported register note sections. */
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static struct core_regset_section i386_linux_regset_sections[] =
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{
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{ ".reg", 68, "general-purpose" },
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{ ".reg2", 108, "floating-point" },
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{ NULL, 0 }
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};
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static struct core_regset_section i386_linux_sse_regset_sections[] =
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{
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{ ".reg", 68, "general-purpose" },
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{ ".reg-xfp", 512, "extended floating-point" },
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{ NULL, 0 }
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};
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static struct core_regset_section i386_linux_avx_regset_sections[] =
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{
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{ ".reg", 68, "general-purpose" },
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{ ".reg-xstate", I386_XSTATE_MAX_SIZE, "XSAVE extended state" },
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{ NULL, 0 }
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};
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/* Return non-zero, when the register is in the corresponding register
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group. Put the LINUX_ORIG_EAX register in the system group. */
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static int
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i386_linux_register_reggroup_p (struct gdbarch *gdbarch, int regnum,
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struct reggroup *group)
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{
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if (regnum == I386_LINUX_ORIG_EAX_REGNUM)
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return (group == system_reggroup
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|| group == save_reggroup
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|| group == restore_reggroup);
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return i386_register_reggroup_p (gdbarch, regnum, group);
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}
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/* Recognizing signal handler frames. */
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/* GNU/Linux has two flavors of signals. Normal signal handlers, and
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"realtime" (RT) signals. The RT signals can provide additional
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information to the signal handler if the SA_SIGINFO flag is set
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when establishing a signal handler using `sigaction'. It is not
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unlikely that future versions of GNU/Linux will support SA_SIGINFO
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for normal signals too. */
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/* When the i386 Linux kernel calls a signal handler and the
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SA_RESTORER flag isn't set, the return address points to a bit of
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code on the stack. This function returns whether the PC appears to
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be within this bit of code.
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The instruction sequence for normal signals is
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pop %eax
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mov $0x77, %eax
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int $0x80
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or 0x58 0xb8 0x77 0x00 0x00 0x00 0xcd 0x80.
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Checking for the code sequence should be somewhat reliable, because
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the effect is to call the system call sigreturn. This is unlikely
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to occur anywhere other than in a signal trampoline.
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It kind of sucks that we have to read memory from the process in
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order to identify a signal trampoline, but there doesn't seem to be
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any other way. Therefore we only do the memory reads if no
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function name could be identified, which should be the case since
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the code is on the stack.
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Detection of signal trampolines for handlers that set the
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SA_RESTORER flag is in general not possible. Unfortunately this is
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what the GNU C Library has been doing for quite some time now.
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However, as of version 2.1.2, the GNU C Library uses signal
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trampolines (named __restore and __restore_rt) that are identical
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to the ones used by the kernel. Therefore, these trampolines are
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supported too. */
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#define LINUX_SIGTRAMP_INSN0 0x58 /* pop %eax */
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#define LINUX_SIGTRAMP_OFFSET0 0
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#define LINUX_SIGTRAMP_INSN1 0xb8 /* mov $NNNN, %eax */
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#define LINUX_SIGTRAMP_OFFSET1 1
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#define LINUX_SIGTRAMP_INSN2 0xcd /* int */
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#define LINUX_SIGTRAMP_OFFSET2 6
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static const gdb_byte linux_sigtramp_code[] =
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{
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LINUX_SIGTRAMP_INSN0, /* pop %eax */
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LINUX_SIGTRAMP_INSN1, 0x77, 0x00, 0x00, 0x00, /* mov $0x77, %eax */
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LINUX_SIGTRAMP_INSN2, 0x80 /* int $0x80 */
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};
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#define LINUX_SIGTRAMP_LEN (sizeof linux_sigtramp_code)
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/* If THIS_FRAME is a sigtramp routine, return the address of the
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start of the routine. Otherwise, return 0. */
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static CORE_ADDR
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i386_linux_sigtramp_start (struct frame_info *this_frame)
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{
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CORE_ADDR pc = get_frame_pc (this_frame);
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gdb_byte buf[LINUX_SIGTRAMP_LEN];
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/* We only recognize a signal trampoline if PC is at the start of
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one of the three instructions. We optimize for finding the PC at
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the start, as will be the case when the trampoline is not the
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first frame on the stack. We assume that in the case where the
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PC is not at the start of the instruction sequence, there will be
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a few trailing readable bytes on the stack. */
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if (!safe_frame_unwind_memory (this_frame, pc, buf, LINUX_SIGTRAMP_LEN))
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return 0;
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if (buf[0] != LINUX_SIGTRAMP_INSN0)
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{
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int adjust;
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switch (buf[0])
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{
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case LINUX_SIGTRAMP_INSN1:
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adjust = LINUX_SIGTRAMP_OFFSET1;
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break;
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case LINUX_SIGTRAMP_INSN2:
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adjust = LINUX_SIGTRAMP_OFFSET2;
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break;
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default:
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return 0;
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}
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pc -= adjust;
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if (!safe_frame_unwind_memory (this_frame, pc, buf, LINUX_SIGTRAMP_LEN))
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return 0;
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}
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if (memcmp (buf, linux_sigtramp_code, LINUX_SIGTRAMP_LEN) != 0)
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return 0;
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return pc;
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}
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/* This function does the same for RT signals. Here the instruction
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sequence is
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mov $0xad, %eax
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int $0x80
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or 0xb8 0xad 0x00 0x00 0x00 0xcd 0x80.
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The effect is to call the system call rt_sigreturn. */
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#define LINUX_RT_SIGTRAMP_INSN0 0xb8 /* mov $NNNN, %eax */
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#define LINUX_RT_SIGTRAMP_OFFSET0 0
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#define LINUX_RT_SIGTRAMP_INSN1 0xcd /* int */
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#define LINUX_RT_SIGTRAMP_OFFSET1 5
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static const gdb_byte linux_rt_sigtramp_code[] =
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{
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LINUX_RT_SIGTRAMP_INSN0, 0xad, 0x00, 0x00, 0x00, /* mov $0xad, %eax */
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LINUX_RT_SIGTRAMP_INSN1, 0x80 /* int $0x80 */
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};
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#define LINUX_RT_SIGTRAMP_LEN (sizeof linux_rt_sigtramp_code)
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/* If THIS_FRAME is an RT sigtramp routine, return the address of the
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start of the routine. Otherwise, return 0. */
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static CORE_ADDR
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i386_linux_rt_sigtramp_start (struct frame_info *this_frame)
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{
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CORE_ADDR pc = get_frame_pc (this_frame);
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gdb_byte buf[LINUX_RT_SIGTRAMP_LEN];
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/* We only recognize a signal trampoline if PC is at the start of
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one of the two instructions. We optimize for finding the PC at
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the start, as will be the case when the trampoline is not the
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first frame on the stack. We assume that in the case where the
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PC is not at the start of the instruction sequence, there will be
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a few trailing readable bytes on the stack. */
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if (!safe_frame_unwind_memory (this_frame, pc, buf, LINUX_RT_SIGTRAMP_LEN))
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return 0;
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if (buf[0] != LINUX_RT_SIGTRAMP_INSN0)
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{
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if (buf[0] != LINUX_RT_SIGTRAMP_INSN1)
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return 0;
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pc -= LINUX_RT_SIGTRAMP_OFFSET1;
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if (!safe_frame_unwind_memory (this_frame, pc, buf,
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LINUX_RT_SIGTRAMP_LEN))
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return 0;
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}
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if (memcmp (buf, linux_rt_sigtramp_code, LINUX_RT_SIGTRAMP_LEN) != 0)
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return 0;
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return pc;
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}
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/* Return whether THIS_FRAME corresponds to a GNU/Linux sigtramp
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routine. */
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static int
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i386_linux_sigtramp_p (struct frame_info *this_frame)
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{
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CORE_ADDR pc = get_frame_pc (this_frame);
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const char *name;
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find_pc_partial_function (pc, &name, NULL, NULL);
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/* If we have NAME, we can optimize the search. The trampolines are
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named __restore and __restore_rt. However, they aren't dynamically
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exported from the shared C library, so the trampoline may appear to
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be part of the preceding function. This should always be sigaction,
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__sigaction, or __libc_sigaction (all aliases to the same function). */
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if (name == NULL || strstr (name, "sigaction") != NULL)
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return (i386_linux_sigtramp_start (this_frame) != 0
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|| i386_linux_rt_sigtramp_start (this_frame) != 0);
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return (strcmp ("__restore", name) == 0
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|| strcmp ("__restore_rt", name) == 0);
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}
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/* Return one if the PC of THIS_FRAME is in a signal trampoline which
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may have DWARF-2 CFI. */
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static int
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i386_linux_dwarf_signal_frame_p (struct gdbarch *gdbarch,
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struct frame_info *this_frame)
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{
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CORE_ADDR pc = get_frame_pc (this_frame);
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const char *name;
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find_pc_partial_function (pc, &name, NULL, NULL);
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/* If a vsyscall DSO is in use, the signal trampolines may have these
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names. */
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if (name && (strcmp (name, "__kernel_sigreturn") == 0
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|| strcmp (name, "__kernel_rt_sigreturn") == 0))
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return 1;
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return 0;
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}
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/* Offset to struct sigcontext in ucontext, from <asm/ucontext.h>. */
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#define I386_LINUX_UCONTEXT_SIGCONTEXT_OFFSET 20
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/* Assuming THIS_FRAME is a GNU/Linux sigtramp routine, return the
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address of the associated sigcontext structure. */
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static CORE_ADDR
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i386_linux_sigcontext_addr (struct frame_info *this_frame)
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{
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struct gdbarch *gdbarch = get_frame_arch (this_frame);
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enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
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CORE_ADDR pc;
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CORE_ADDR sp;
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gdb_byte buf[4];
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get_frame_register (this_frame, I386_ESP_REGNUM, buf);
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sp = extract_unsigned_integer (buf, 4, byte_order);
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pc = i386_linux_sigtramp_start (this_frame);
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if (pc)
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{
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/* The sigcontext structure lives on the stack, right after
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the signum argument. We determine the address of the
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sigcontext structure by looking at the frame's stack
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pointer. Keep in mind that the first instruction of the
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sigtramp code is "pop %eax". If the PC is after this
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instruction, adjust the returned value accordingly. */
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if (pc == get_frame_pc (this_frame))
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return sp + 4;
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return sp;
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}
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pc = i386_linux_rt_sigtramp_start (this_frame);
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if (pc)
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{
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CORE_ADDR ucontext_addr;
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/* The sigcontext structure is part of the user context. A
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pointer to the user context is passed as the third argument
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to the signal handler. */
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read_memory (sp + 8, buf, 4);
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ucontext_addr = extract_unsigned_integer (buf, 4, byte_order);
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return ucontext_addr + I386_LINUX_UCONTEXT_SIGCONTEXT_OFFSET;
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}
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error (_("Couldn't recognize signal trampoline."));
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return 0;
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}
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/* Set the program counter for process PTID to PC. */
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static void
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i386_linux_write_pc (struct regcache *regcache, CORE_ADDR pc)
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{
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regcache_cooked_write_unsigned (regcache, I386_EIP_REGNUM, pc);
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/* We must be careful with modifying the program counter. If we
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just interrupted a system call, the kernel might try to restart
|
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it when we resume the inferior. On restarting the system call,
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the kernel will try backing up the program counter even though it
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no longer points at the system call. This typically results in a
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SIGSEGV or SIGILL. We can prevent this by writing `-1' in the
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"orig_eax" pseudo-register.
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Note that "orig_eax" is saved when setting up a dummy call frame.
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This means that it is properly restored when that frame is
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popped, and that the interrupted system call will be restarted
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when we resume the inferior on return from a function call from
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within GDB. In all other cases the system call will not be
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restarted. */
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regcache_cooked_write_unsigned (regcache, I386_LINUX_ORIG_EAX_REGNUM, -1);
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}
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|
||
/* Record all registers but IP register for process-record. */
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static int
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i386_all_but_ip_registers_record (struct regcache *regcache)
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||
{
|
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if (record_arch_list_add_reg (regcache, I386_EAX_REGNUM))
|
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return -1;
|
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if (record_arch_list_add_reg (regcache, I386_ECX_REGNUM))
|
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return -1;
|
||
if (record_arch_list_add_reg (regcache, I386_EDX_REGNUM))
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return -1;
|
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if (record_arch_list_add_reg (regcache, I386_EBX_REGNUM))
|
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return -1;
|
||
if (record_arch_list_add_reg (regcache, I386_ESP_REGNUM))
|
||
return -1;
|
||
if (record_arch_list_add_reg (regcache, I386_EBP_REGNUM))
|
||
return -1;
|
||
if (record_arch_list_add_reg (regcache, I386_ESI_REGNUM))
|
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return -1;
|
||
if (record_arch_list_add_reg (regcache, I386_EDI_REGNUM))
|
||
return -1;
|
||
if (record_arch_list_add_reg (regcache, I386_EFLAGS_REGNUM))
|
||
return -1;
|
||
|
||
return 0;
|
||
}
|
||
|
||
/* i386_canonicalize_syscall maps from the native i386 Linux set
|
||
of syscall ids into a canonical set of syscall ids used by
|
||
process record (a mostly trivial mapping, since the canonical
|
||
set was originally taken from the i386 set). */
|
||
|
||
static enum gdb_syscall
|
||
i386_canonicalize_syscall (int syscall)
|
||
{
|
||
enum { i386_syscall_max = 499 };
|
||
|
||
if (syscall <= i386_syscall_max)
|
||
return syscall;
|
||
else
|
||
return -1;
|
||
}
|
||
|
||
/* Parse the arguments of current system call instruction and record
|
||
the values of the registers and memory that will be changed into
|
||
"record_arch_list". This instruction is "int 0x80" (Linux
|
||
Kernel2.4) or "sysenter" (Linux Kernel 2.6).
|
||
|
||
Return -1 if something wrong. */
|
||
|
||
static struct linux_record_tdep i386_linux_record_tdep;
|
||
|
||
static int
|
||
i386_linux_intx80_sysenter_syscall_record (struct regcache *regcache)
|
||
{
|
||
int ret;
|
||
LONGEST syscall_native;
|
||
enum gdb_syscall syscall_gdb;
|
||
|
||
regcache_raw_read_signed (regcache, I386_EAX_REGNUM, &syscall_native);
|
||
|
||
syscall_gdb = i386_canonicalize_syscall (syscall_native);
|
||
|
||
if (syscall_gdb < 0)
|
||
{
|
||
printf_unfiltered (_("Process record and replay target doesn't "
|
||
"support syscall number %s\n"),
|
||
plongest (syscall_native));
|
||
return -1;
|
||
}
|
||
|
||
if (syscall_gdb == gdb_sys_sigreturn
|
||
|| syscall_gdb == gdb_sys_rt_sigreturn)
|
||
{
|
||
if (i386_all_but_ip_registers_record (regcache))
|
||
return -1;
|
||
return 0;
|
||
}
|
||
|
||
ret = record_linux_system_call (syscall_gdb, regcache,
|
||
&i386_linux_record_tdep);
|
||
if (ret)
|
||
return ret;
|
||
|
||
/* Record the return value of the system call. */
|
||
if (record_arch_list_add_reg (regcache, I386_EAX_REGNUM))
|
||
return -1;
|
||
|
||
return 0;
|
||
}
|
||
|
||
#define I386_LINUX_xstate 270
|
||
#define I386_LINUX_frame_size 732
|
||
|
||
static int
|
||
i386_linux_record_signal (struct gdbarch *gdbarch,
|
||
struct regcache *regcache,
|
||
enum gdb_signal signal)
|
||
{
|
||
ULONGEST esp;
|
||
|
||
if (i386_all_but_ip_registers_record (regcache))
|
||
return -1;
|
||
|
||
if (record_arch_list_add_reg (regcache, I386_EIP_REGNUM))
|
||
return -1;
|
||
|
||
/* Record the change in the stack. */
|
||
regcache_raw_read_unsigned (regcache, I386_ESP_REGNUM, &esp);
|
||
/* This is for xstate.
|
||
sp -= sizeof (struct _fpstate); */
|
||
esp -= I386_LINUX_xstate;
|
||
/* This is for frame_size.
|
||
sp -= sizeof (struct rt_sigframe); */
|
||
esp -= I386_LINUX_frame_size;
|
||
if (record_arch_list_add_mem (esp,
|
||
I386_LINUX_xstate + I386_LINUX_frame_size))
|
||
return -1;
|
||
|
||
if (record_arch_list_add_end ())
|
||
return -1;
|
||
|
||
return 0;
|
||
}
|
||
|
||
|
||
/* Core of the implementation for gdbarch get_syscall_number. Get pending
|
||
syscall number from REGCACHE. If there is no pending syscall -1 will be
|
||
returned. Pending syscall means ptrace has stepped into the syscall but
|
||
another ptrace call will step out. PC is right after the int $0x80
|
||
/ syscall / sysenter instruction in both cases, PC does not change during
|
||
the second ptrace step. */
|
||
|
||
static LONGEST
|
||
i386_linux_get_syscall_number_from_regcache (struct regcache *regcache)
|
||
{
|
||
struct gdbarch *gdbarch = get_regcache_arch (regcache);
|
||
enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
|
||
/* The content of a register. */
|
||
gdb_byte buf[4];
|
||
/* The result. */
|
||
LONGEST ret;
|
||
|
||
/* Getting the system call number from the register.
|
||
When dealing with x86 architecture, this information
|
||
is stored at %eax register. */
|
||
regcache_cooked_read (regcache, I386_LINUX_ORIG_EAX_REGNUM, buf);
|
||
|
||
ret = extract_signed_integer (buf, 4, byte_order);
|
||
|
||
return ret;
|
||
}
|
||
|
||
/* Wrapper for i386_linux_get_syscall_number_from_regcache to make it
|
||
compatible with gdbarch get_syscall_number method prototype. */
|
||
|
||
static LONGEST
|
||
i386_linux_get_syscall_number (struct gdbarch *gdbarch,
|
||
ptid_t ptid)
|
||
{
|
||
struct regcache *regcache = get_thread_regcache (ptid);
|
||
|
||
return i386_linux_get_syscall_number_from_regcache (regcache);
|
||
}
|
||
|
||
/* The register sets used in GNU/Linux ELF core-dumps are identical to
|
||
the register sets in `struct user' that are used for a.out
|
||
core-dumps. These are also used by ptrace(2). The corresponding
|
||
types are `elf_gregset_t' for the general-purpose registers (with
|
||
`elf_greg_t' the type of a single GP register) and `elf_fpregset_t'
|
||
for the floating-point registers.
|
||
|
||
Those types used to be available under the names `gregset_t' and
|
||
`fpregset_t' too, and GDB used those names in the past. But those
|
||
names are now used for the register sets used in the `mcontext_t'
|
||
type, which have a different size and layout. */
|
||
|
||
/* Mapping between the general-purpose registers in `struct user'
|
||
format and GDB's register cache layout. */
|
||
|
||
/* From <sys/reg.h>. */
|
||
int i386_linux_gregset_reg_offset[] =
|
||
{
|
||
6 * 4, /* %eax */
|
||
1 * 4, /* %ecx */
|
||
2 * 4, /* %edx */
|
||
0 * 4, /* %ebx */
|
||
15 * 4, /* %esp */
|
||
5 * 4, /* %ebp */
|
||
3 * 4, /* %esi */
|
||
4 * 4, /* %edi */
|
||
12 * 4, /* %eip */
|
||
14 * 4, /* %eflags */
|
||
13 * 4, /* %cs */
|
||
16 * 4, /* %ss */
|
||
7 * 4, /* %ds */
|
||
8 * 4, /* %es */
|
||
9 * 4, /* %fs */
|
||
10 * 4, /* %gs */
|
||
-1, -1, -1, -1, -1, -1, -1, -1,
|
||
-1, -1, -1, -1, -1, -1, -1, -1,
|
||
-1, -1, -1, -1, -1, -1, -1, -1,
|
||
-1,
|
||
-1, -1, -1, -1, -1, -1, -1, -1,
|
||
11 * 4 /* "orig_eax" */
|
||
};
|
||
|
||
/* Mapping between the general-purpose registers in `struct
|
||
sigcontext' format and GDB's register cache layout. */
|
||
|
||
/* From <asm/sigcontext.h>. */
|
||
static int i386_linux_sc_reg_offset[] =
|
||
{
|
||
11 * 4, /* %eax */
|
||
10 * 4, /* %ecx */
|
||
9 * 4, /* %edx */
|
||
8 * 4, /* %ebx */
|
||
7 * 4, /* %esp */
|
||
6 * 4, /* %ebp */
|
||
5 * 4, /* %esi */
|
||
4 * 4, /* %edi */
|
||
14 * 4, /* %eip */
|
||
16 * 4, /* %eflags */
|
||
15 * 4, /* %cs */
|
||
18 * 4, /* %ss */
|
||
3 * 4, /* %ds */
|
||
2 * 4, /* %es */
|
||
1 * 4, /* %fs */
|
||
0 * 4 /* %gs */
|
||
};
|
||
|
||
/* Get XSAVE extended state xcr0 from core dump. */
|
||
|
||
uint64_t
|
||
i386_linux_core_read_xcr0 (struct gdbarch *gdbarch,
|
||
struct target_ops *target, bfd *abfd)
|
||
{
|
||
asection *xstate = bfd_get_section_by_name (abfd, ".reg-xstate");
|
||
uint64_t xcr0;
|
||
|
||
if (xstate)
|
||
{
|
||
size_t size = bfd_section_size (abfd, xstate);
|
||
|
||
/* Check extended state size. */
|
||
if (size < I386_XSTATE_AVX_SIZE)
|
||
xcr0 = I386_XSTATE_SSE_MASK;
|
||
else
|
||
{
|
||
char contents[8];
|
||
|
||
if (! bfd_get_section_contents (abfd, xstate, contents,
|
||
I386_LINUX_XSAVE_XCR0_OFFSET,
|
||
8))
|
||
{
|
||
warning (_("Couldn't read `xcr0' bytes from "
|
||
"`.reg-xstate' section in core file."));
|
||
return 0;
|
||
}
|
||
|
||
xcr0 = bfd_get_64 (abfd, contents);
|
||
}
|
||
}
|
||
else
|
||
xcr0 = 0;
|
||
|
||
return xcr0;
|
||
}
|
||
|
||
/* Get Linux/x86 target description from core dump. */
|
||
|
||
static const struct target_desc *
|
||
i386_linux_core_read_description (struct gdbarch *gdbarch,
|
||
struct target_ops *target,
|
||
bfd *abfd)
|
||
{
|
||
/* Linux/i386. */
|
||
uint64_t xcr0 = i386_linux_core_read_xcr0 (gdbarch, target, abfd);
|
||
switch ((xcr0 & I386_XSTATE_AVX_MASK))
|
||
{
|
||
case I386_XSTATE_AVX_MASK:
|
||
return tdesc_i386_avx_linux;
|
||
case I386_XSTATE_SSE_MASK:
|
||
return tdesc_i386_linux;
|
||
case I386_XSTATE_X87_MASK:
|
||
return tdesc_i386_mmx_linux;
|
||
default:
|
||
break;
|
||
}
|
||
|
||
if (bfd_get_section_by_name (abfd, ".reg-xfp") != NULL)
|
||
return tdesc_i386_linux;
|
||
else
|
||
return tdesc_i386_mmx_linux;
|
||
}
|
||
|
||
/* Linux kernel shows PC value after the 'int $0x80' instruction even if
|
||
inferior is still inside the syscall. On next PTRACE_SINGLESTEP it will
|
||
finish the syscall but PC will not change.
|
||
|
||
Some vDSOs contain 'int $0x80; ret' and during stepping out of the syscall
|
||
i386_displaced_step_fixup would keep PC at the displaced pad location.
|
||
As PC is pointing to the 'ret' instruction before the step
|
||
i386_displaced_step_fixup would expect inferior has just executed that 'ret'
|
||
and PC should not be adjusted. In reality it finished syscall instead and
|
||
PC should get relocated back to its vDSO address. Hide the 'ret'
|
||
instruction by 'nop' so that i386_displaced_step_fixup is not confused.
|
||
|
||
It is not fully correct as the bytes in struct displaced_step_closure will
|
||
not match the inferior code. But we would need some new flag in
|
||
displaced_step_closure otherwise to keep the state that syscall is finishing
|
||
for the later i386_displaced_step_fixup execution as the syscall execution
|
||
is already no longer detectable there. The new flag field would mean
|
||
i386-linux-tdep.c needs to wrap all the displacement methods of i386-tdep.c
|
||
which does not seem worth it. The same effect is achieved by patching that
|
||
'nop' instruction there instead. */
|
||
|
||
static struct displaced_step_closure *
|
||
i386_linux_displaced_step_copy_insn (struct gdbarch *gdbarch,
|
||
CORE_ADDR from, CORE_ADDR to,
|
||
struct regcache *regs)
|
||
{
|
||
struct displaced_step_closure *closure;
|
||
|
||
closure = i386_displaced_step_copy_insn (gdbarch, from, to, regs);
|
||
|
||
if (i386_linux_get_syscall_number_from_regcache (regs) != -1)
|
||
{
|
||
/* Since we use simple_displaced_step_copy_insn, our closure is a
|
||
copy of the instruction. */
|
||
gdb_byte *insn = (gdb_byte *) closure;
|
||
|
||
/* Fake nop. */
|
||
insn[0] = 0x90;
|
||
}
|
||
|
||
return closure;
|
||
}
|
||
|
||
static void
|
||
i386_linux_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
|
||
{
|
||
struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
|
||
const struct target_desc *tdesc = info.target_desc;
|
||
struct tdesc_arch_data *tdesc_data = (void *) info.tdep_info;
|
||
const struct tdesc_feature *feature;
|
||
int valid_p;
|
||
|
||
gdb_assert (tdesc_data);
|
||
|
||
linux_init_abi (info, gdbarch);
|
||
|
||
/* GNU/Linux uses ELF. */
|
||
i386_elf_init_abi (info, gdbarch);
|
||
|
||
/* Reserve a number for orig_eax. */
|
||
set_gdbarch_num_regs (gdbarch, I386_LINUX_NUM_REGS);
|
||
|
||
if (! tdesc_has_registers (tdesc))
|
||
tdesc = tdesc_i386_linux;
|
||
tdep->tdesc = tdesc;
|
||
|
||
feature = tdesc_find_feature (tdesc, "org.gnu.gdb.i386.linux");
|
||
if (feature == NULL)
|
||
return;
|
||
|
||
valid_p = tdesc_numbered_register (feature, tdesc_data,
|
||
I386_LINUX_ORIG_EAX_REGNUM,
|
||
"orig_eax");
|
||
if (!valid_p)
|
||
return;
|
||
|
||
/* Add the %orig_eax register used for syscall restarting. */
|
||
set_gdbarch_write_pc (gdbarch, i386_linux_write_pc);
|
||
|
||
tdep->register_reggroup_p = i386_linux_register_reggroup_p;
|
||
|
||
tdep->gregset_reg_offset = i386_linux_gregset_reg_offset;
|
||
tdep->gregset_num_regs = ARRAY_SIZE (i386_linux_gregset_reg_offset);
|
||
tdep->sizeof_gregset = 17 * 4;
|
||
|
||
tdep->jb_pc_offset = 20; /* From <bits/setjmp.h>. */
|
||
|
||
tdep->sigtramp_p = i386_linux_sigtramp_p;
|
||
tdep->sigcontext_addr = i386_linux_sigcontext_addr;
|
||
tdep->sc_reg_offset = i386_linux_sc_reg_offset;
|
||
tdep->sc_num_regs = ARRAY_SIZE (i386_linux_sc_reg_offset);
|
||
|
||
tdep->xsave_xcr0_offset = I386_LINUX_XSAVE_XCR0_OFFSET;
|
||
|
||
set_gdbarch_process_record (gdbarch, i386_process_record);
|
||
set_gdbarch_process_record_signal (gdbarch, i386_linux_record_signal);
|
||
|
||
/* Initialize the i386_linux_record_tdep. */
|
||
/* These values are the size of the type that will be used in a system
|
||
call. They are obtained from Linux Kernel source. */
|
||
i386_linux_record_tdep.size_pointer
|
||
= gdbarch_ptr_bit (gdbarch) / TARGET_CHAR_BIT;
|
||
i386_linux_record_tdep.size__old_kernel_stat = 32;
|
||
i386_linux_record_tdep.size_tms = 16;
|
||
i386_linux_record_tdep.size_loff_t = 8;
|
||
i386_linux_record_tdep.size_flock = 16;
|
||
i386_linux_record_tdep.size_oldold_utsname = 45;
|
||
i386_linux_record_tdep.size_ustat = 20;
|
||
i386_linux_record_tdep.size_old_sigaction = 140;
|
||
i386_linux_record_tdep.size_old_sigset_t = 128;
|
||
i386_linux_record_tdep.size_rlimit = 8;
|
||
i386_linux_record_tdep.size_rusage = 72;
|
||
i386_linux_record_tdep.size_timeval = 8;
|
||
i386_linux_record_tdep.size_timezone = 8;
|
||
i386_linux_record_tdep.size_old_gid_t = 2;
|
||
i386_linux_record_tdep.size_old_uid_t = 2;
|
||
i386_linux_record_tdep.size_fd_set = 128;
|
||
i386_linux_record_tdep.size_dirent = 268;
|
||
i386_linux_record_tdep.size_dirent64 = 276;
|
||
i386_linux_record_tdep.size_statfs = 64;
|
||
i386_linux_record_tdep.size_statfs64 = 84;
|
||
i386_linux_record_tdep.size_sockaddr = 16;
|
||
i386_linux_record_tdep.size_int
|
||
= gdbarch_int_bit (gdbarch) / TARGET_CHAR_BIT;
|
||
i386_linux_record_tdep.size_long
|
||
= gdbarch_long_bit (gdbarch) / TARGET_CHAR_BIT;
|
||
i386_linux_record_tdep.size_ulong
|
||
= gdbarch_long_bit (gdbarch) / TARGET_CHAR_BIT;
|
||
i386_linux_record_tdep.size_msghdr = 28;
|
||
i386_linux_record_tdep.size_itimerval = 16;
|
||
i386_linux_record_tdep.size_stat = 88;
|
||
i386_linux_record_tdep.size_old_utsname = 325;
|
||
i386_linux_record_tdep.size_sysinfo = 64;
|
||
i386_linux_record_tdep.size_msqid_ds = 88;
|
||
i386_linux_record_tdep.size_shmid_ds = 84;
|
||
i386_linux_record_tdep.size_new_utsname = 390;
|
||
i386_linux_record_tdep.size_timex = 128;
|
||
i386_linux_record_tdep.size_mem_dqinfo = 24;
|
||
i386_linux_record_tdep.size_if_dqblk = 68;
|
||
i386_linux_record_tdep.size_fs_quota_stat = 68;
|
||
i386_linux_record_tdep.size_timespec = 8;
|
||
i386_linux_record_tdep.size_pollfd = 8;
|
||
i386_linux_record_tdep.size_NFS_FHSIZE = 32;
|
||
i386_linux_record_tdep.size_knfsd_fh = 132;
|
||
i386_linux_record_tdep.size_TASK_COMM_LEN = 16;
|
||
i386_linux_record_tdep.size_sigaction = 140;
|
||
i386_linux_record_tdep.size_sigset_t = 8;
|
||
i386_linux_record_tdep.size_siginfo_t = 128;
|
||
i386_linux_record_tdep.size_cap_user_data_t = 12;
|
||
i386_linux_record_tdep.size_stack_t = 12;
|
||
i386_linux_record_tdep.size_off_t = i386_linux_record_tdep.size_long;
|
||
i386_linux_record_tdep.size_stat64 = 96;
|
||
i386_linux_record_tdep.size_gid_t = 2;
|
||
i386_linux_record_tdep.size_uid_t = 2;
|
||
i386_linux_record_tdep.size_PAGE_SIZE = 4096;
|
||
i386_linux_record_tdep.size_flock64 = 24;
|
||
i386_linux_record_tdep.size_user_desc = 16;
|
||
i386_linux_record_tdep.size_io_event = 32;
|
||
i386_linux_record_tdep.size_iocb = 64;
|
||
i386_linux_record_tdep.size_epoll_event = 12;
|
||
i386_linux_record_tdep.size_itimerspec
|
||
= i386_linux_record_tdep.size_timespec * 2;
|
||
i386_linux_record_tdep.size_mq_attr = 32;
|
||
i386_linux_record_tdep.size_siginfo = 128;
|
||
i386_linux_record_tdep.size_termios = 36;
|
||
i386_linux_record_tdep.size_termios2 = 44;
|
||
i386_linux_record_tdep.size_pid_t = 4;
|
||
i386_linux_record_tdep.size_winsize = 8;
|
||
i386_linux_record_tdep.size_serial_struct = 60;
|
||
i386_linux_record_tdep.size_serial_icounter_struct = 80;
|
||
i386_linux_record_tdep.size_hayes_esp_config = 12;
|
||
i386_linux_record_tdep.size_size_t = 4;
|
||
i386_linux_record_tdep.size_iovec = 8;
|
||
|
||
/* These values are the second argument of system call "sys_ioctl".
|
||
They are obtained from Linux Kernel source. */
|
||
i386_linux_record_tdep.ioctl_TCGETS = 0x5401;
|
||
i386_linux_record_tdep.ioctl_TCSETS = 0x5402;
|
||
i386_linux_record_tdep.ioctl_TCSETSW = 0x5403;
|
||
i386_linux_record_tdep.ioctl_TCSETSF = 0x5404;
|
||
i386_linux_record_tdep.ioctl_TCGETA = 0x5405;
|
||
i386_linux_record_tdep.ioctl_TCSETA = 0x5406;
|
||
i386_linux_record_tdep.ioctl_TCSETAW = 0x5407;
|
||
i386_linux_record_tdep.ioctl_TCSETAF = 0x5408;
|
||
i386_linux_record_tdep.ioctl_TCSBRK = 0x5409;
|
||
i386_linux_record_tdep.ioctl_TCXONC = 0x540A;
|
||
i386_linux_record_tdep.ioctl_TCFLSH = 0x540B;
|
||
i386_linux_record_tdep.ioctl_TIOCEXCL = 0x540C;
|
||
i386_linux_record_tdep.ioctl_TIOCNXCL = 0x540D;
|
||
i386_linux_record_tdep.ioctl_TIOCSCTTY = 0x540E;
|
||
i386_linux_record_tdep.ioctl_TIOCGPGRP = 0x540F;
|
||
i386_linux_record_tdep.ioctl_TIOCSPGRP = 0x5410;
|
||
i386_linux_record_tdep.ioctl_TIOCOUTQ = 0x5411;
|
||
i386_linux_record_tdep.ioctl_TIOCSTI = 0x5412;
|
||
i386_linux_record_tdep.ioctl_TIOCGWINSZ = 0x5413;
|
||
i386_linux_record_tdep.ioctl_TIOCSWINSZ = 0x5414;
|
||
i386_linux_record_tdep.ioctl_TIOCMGET = 0x5415;
|
||
i386_linux_record_tdep.ioctl_TIOCMBIS = 0x5416;
|
||
i386_linux_record_tdep.ioctl_TIOCMBIC = 0x5417;
|
||
i386_linux_record_tdep.ioctl_TIOCMSET = 0x5418;
|
||
i386_linux_record_tdep.ioctl_TIOCGSOFTCAR = 0x5419;
|
||
i386_linux_record_tdep.ioctl_TIOCSSOFTCAR = 0x541A;
|
||
i386_linux_record_tdep.ioctl_FIONREAD = 0x541B;
|
||
i386_linux_record_tdep.ioctl_TIOCINQ = i386_linux_record_tdep.ioctl_FIONREAD;
|
||
i386_linux_record_tdep.ioctl_TIOCLINUX = 0x541C;
|
||
i386_linux_record_tdep.ioctl_TIOCCONS = 0x541D;
|
||
i386_linux_record_tdep.ioctl_TIOCGSERIAL = 0x541E;
|
||
i386_linux_record_tdep.ioctl_TIOCSSERIAL = 0x541F;
|
||
i386_linux_record_tdep.ioctl_TIOCPKT = 0x5420;
|
||
i386_linux_record_tdep.ioctl_FIONBIO = 0x5421;
|
||
i386_linux_record_tdep.ioctl_TIOCNOTTY = 0x5422;
|
||
i386_linux_record_tdep.ioctl_TIOCSETD = 0x5423;
|
||
i386_linux_record_tdep.ioctl_TIOCGETD = 0x5424;
|
||
i386_linux_record_tdep.ioctl_TCSBRKP = 0x5425;
|
||
i386_linux_record_tdep.ioctl_TIOCTTYGSTRUCT = 0x5426;
|
||
i386_linux_record_tdep.ioctl_TIOCSBRK = 0x5427;
|
||
i386_linux_record_tdep.ioctl_TIOCCBRK = 0x5428;
|
||
i386_linux_record_tdep.ioctl_TIOCGSID = 0x5429;
|
||
i386_linux_record_tdep.ioctl_TCGETS2 = 0x802c542a;
|
||
i386_linux_record_tdep.ioctl_TCSETS2 = 0x402c542b;
|
||
i386_linux_record_tdep.ioctl_TCSETSW2 = 0x402c542c;
|
||
i386_linux_record_tdep.ioctl_TCSETSF2 = 0x402c542d;
|
||
i386_linux_record_tdep.ioctl_TIOCGPTN = 0x80045430;
|
||
i386_linux_record_tdep.ioctl_TIOCSPTLCK = 0x40045431;
|
||
i386_linux_record_tdep.ioctl_FIONCLEX = 0x5450;
|
||
i386_linux_record_tdep.ioctl_FIOCLEX = 0x5451;
|
||
i386_linux_record_tdep.ioctl_FIOASYNC = 0x5452;
|
||
i386_linux_record_tdep.ioctl_TIOCSERCONFIG = 0x5453;
|
||
i386_linux_record_tdep.ioctl_TIOCSERGWILD = 0x5454;
|
||
i386_linux_record_tdep.ioctl_TIOCSERSWILD = 0x5455;
|
||
i386_linux_record_tdep.ioctl_TIOCGLCKTRMIOS = 0x5456;
|
||
i386_linux_record_tdep.ioctl_TIOCSLCKTRMIOS = 0x5457;
|
||
i386_linux_record_tdep.ioctl_TIOCSERGSTRUCT = 0x5458;
|
||
i386_linux_record_tdep.ioctl_TIOCSERGETLSR = 0x5459;
|
||
i386_linux_record_tdep.ioctl_TIOCSERGETMULTI = 0x545A;
|
||
i386_linux_record_tdep.ioctl_TIOCSERSETMULTI = 0x545B;
|
||
i386_linux_record_tdep.ioctl_TIOCMIWAIT = 0x545C;
|
||
i386_linux_record_tdep.ioctl_TIOCGICOUNT = 0x545D;
|
||
i386_linux_record_tdep.ioctl_TIOCGHAYESESP = 0x545E;
|
||
i386_linux_record_tdep.ioctl_TIOCSHAYESESP = 0x545F;
|
||
i386_linux_record_tdep.ioctl_FIOQSIZE = 0x5460;
|
||
|
||
/* These values are the second argument of system call "sys_fcntl"
|
||
and "sys_fcntl64". They are obtained from Linux Kernel source. */
|
||
i386_linux_record_tdep.fcntl_F_GETLK = 5;
|
||
i386_linux_record_tdep.fcntl_F_GETLK64 = 12;
|
||
i386_linux_record_tdep.fcntl_F_SETLK64 = 13;
|
||
i386_linux_record_tdep.fcntl_F_SETLKW64 = 14;
|
||
|
||
i386_linux_record_tdep.arg1 = I386_EBX_REGNUM;
|
||
i386_linux_record_tdep.arg2 = I386_ECX_REGNUM;
|
||
i386_linux_record_tdep.arg3 = I386_EDX_REGNUM;
|
||
i386_linux_record_tdep.arg4 = I386_ESI_REGNUM;
|
||
i386_linux_record_tdep.arg5 = I386_EDI_REGNUM;
|
||
i386_linux_record_tdep.arg6 = I386_EBP_REGNUM;
|
||
|
||
tdep->i386_intx80_record = i386_linux_intx80_sysenter_syscall_record;
|
||
tdep->i386_sysenter_record = i386_linux_intx80_sysenter_syscall_record;
|
||
tdep->i386_syscall_record = i386_linux_intx80_sysenter_syscall_record;
|
||
|
||
/* N_FUN symbols in shared libaries have 0 for their values and need
|
||
to be relocated. */
|
||
set_gdbarch_sofun_address_maybe_missing (gdbarch, 1);
|
||
|
||
/* GNU/Linux uses SVR4-style shared libraries. */
|
||
set_gdbarch_skip_trampoline_code (gdbarch, find_solib_trampoline_target);
|
||
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);
|
||
|
||
dwarf2_frame_set_signal_frame_p (gdbarch, i386_linux_dwarf_signal_frame_p);
|
||
|
||
/* Enable TLS support. */
|
||
set_gdbarch_fetch_tls_load_module_address (gdbarch,
|
||
svr4_fetch_objfile_link_map);
|
||
|
||
/* Install supported register note sections. */
|
||
if (tdesc_find_feature (tdesc, "org.gnu.gdb.i386.avx"))
|
||
set_gdbarch_core_regset_sections (gdbarch, i386_linux_avx_regset_sections);
|
||
else if (tdesc_find_feature (tdesc, "org.gnu.gdb.i386.sse"))
|
||
set_gdbarch_core_regset_sections (gdbarch, i386_linux_sse_regset_sections);
|
||
else
|
||
set_gdbarch_core_regset_sections (gdbarch, i386_linux_regset_sections);
|
||
|
||
set_gdbarch_core_read_description (gdbarch,
|
||
i386_linux_core_read_description);
|
||
|
||
/* Displaced stepping. */
|
||
set_gdbarch_displaced_step_copy_insn (gdbarch,
|
||
i386_linux_displaced_step_copy_insn);
|
||
set_gdbarch_displaced_step_fixup (gdbarch, i386_displaced_step_fixup);
|
||
set_gdbarch_displaced_step_free_closure (gdbarch,
|
||
simple_displaced_step_free_closure);
|
||
set_gdbarch_displaced_step_location (gdbarch,
|
||
displaced_step_at_entry_point);
|
||
|
||
/* Functions for 'catch syscall'. */
|
||
set_xml_syscall_file_name (XML_SYSCALL_FILENAME_I386);
|
||
set_gdbarch_get_syscall_number (gdbarch,
|
||
i386_linux_get_syscall_number);
|
||
|
||
set_gdbarch_get_siginfo_type (gdbarch, linux_get_siginfo_type);
|
||
}
|
||
|
||
/* Provide a prototype to silence -Wmissing-prototypes. */
|
||
extern void _initialize_i386_linux_tdep (void);
|
||
|
||
void
|
||
_initialize_i386_linux_tdep (void)
|
||
{
|
||
gdbarch_register_osabi (bfd_arch_i386, 0, GDB_OSABI_LINUX,
|
||
i386_linux_init_abi);
|
||
|
||
/* Initialize the Linux target description. */
|
||
initialize_tdesc_i386_linux ();
|
||
initialize_tdesc_i386_mmx_linux ();
|
||
initialize_tdesc_i386_avx_linux ();
|
||
}
|