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/*
* Copyright (C) 2005 Atmel Corporation
*
* This file is subject to the terms and conditions of the GNU Lesser General
* Public License. See the file "COPYING.LIB" in the main directory of this
* archive for more details.
*/
/*
* Clone the process without copying the address space. The
* calling process is suspended until the child either exits
* or calls execve.
*
* This all means that we cannot rely on the stack to store
* away registers, since they will be overwritten by the child
* as soon as it makes another function call (e.g. execve()).
* Fortunately, the Linux kernel preserves LR across system calls.
*/
#include <features.h>
#include <sys/syscall.h>
.global __vfork
.type __vfork,@function
.align 1
__vfork:
mov r8, __NR_vfork
scall
cp.w r12, -4096
retls r12
/* vfork failed, so we may use the stack freely */
pushm r4-r7,lr
#ifdef __PIC__
lddpc r6, .L_GOT
rsub r4, r12, 0
.L_RGOT:
rsub r6, pc
mcall r6[__errno_location@got]
#else
rsub r4, r12, 0
mcall .L__errno_location
#endif
st.w r12[0], r4
popm r4-r7,pc,r12=-1
.align 2
#ifdef __PIC__
.L_GOT:
.long .L_RGOT - _GLOBAL_OFFSET_TABLE_
#else
.L__errno_location:
.long __errno_location
#endif
.size __vfork, . - __vfork
weak_alias(__vfork,vfork)
libc_hidden_weak(vfork)
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