glibc/sysdeps/unix/sysv/linux/m68k/m68k-helpers.S

96 lines
3.2 KiB
ArmAsm

/* Copyright (C) 2010-2016 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Maxim Kuvyrkov <maxim@codesourcery.com>, 2010.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
In addition to the permissions in the GNU Lesser General Public
License, the Free Software Foundation gives you unlimited
permission to link the compiled version of this file with other
programs, and to distribute those programs without any restriction
coming from the use of this file. (The GNU Lesser General Public
License restrictions do apply in other respects; for example, they
cover modification of the file, and distribution when not linked
into another program.)
Note that people who make modified versions of this file are not
obligated to grant this special exception for their modified
versions; it is their choice whether to do so. The GNU Lesser
General Public License gives permission to release a modified
version without this exception; this exception also makes it
possible to release a modified version which carries forward this
exception.
The GNU C Library 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library. If not, see
<http://www.gnu.org/licenses/>. */
#include <sysdep.h>
#include <m68k-vdso.h>
.text
.hidden __vdso_read_tp_stub
ENTRY (__vdso_read_tp_stub)
move.l #__NR_get_thread_area, %d0
trap #0
move.l %d0, %a0
rts
END (__vdso_read_tp_stub)
# ifdef SHARED
/* GCC will emit calls to this routine. Linux has an
equivalent helper function (which clobbers fewer registers than
a normal function call) in a vdso; tail call to the
helper. */
# if IS_IN (rtld)
/* rtld gets a hidden copy of __m68k_read_tp. */
.hidden __m68k_read_tp
# endif
ENTRY (__m68k_read_tp)
LOAD_GOT (%a0)
move.l M68K_VDSO_SYMBOL (__vdso_read_tp)@GOT(%a0), %a0
move.l (%a0), %a0
jmp (%a0)
END (__m68k_read_tp)
/* The following two stubs are for macros in atomic.h, they can't
clobber anything. */
.hidden __vdso_atomic_cmpxchg_32_stub
ENTRY (__vdso_atomic_cmpxchg_32_stub)
move.l %d2, -(%sp)
cfi_adjust_cfa_offset (4)
cfi_rel_offset (%d2, 0)
move.l %d0, %d2
move.l #SYS_ify (atomic_cmpxchg_32), %d0
trap #0
move.l (%sp)+, %d2
cfi_adjust_cfa_offset (-4)
cfi_restore (%d2)
rts
END (__vdso_atomic_cmpxchg_32_stub)
.hidden __vdso_atomic_barrier_stub
ENTRY (__vdso_atomic_barrier_stub)
move.l %d0, -(%sp)
cfi_adjust_cfa_offset (4)
move.l #SYS_ify (atomic_barrier), %d0
trap #0
move.l (%sp)+, %d0
cfi_adjust_cfa_offset (-4)
rts
END (__vdso_atomic_barrier_stub)
# else /* !SHARED */
/* If the vDSO is not available, use a syscall to get TP. */
strong_alias (__vdso_read_tp_stub, __m68k_read_tp)
# endif /* SHARED */