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/*
* Copyright (C) 2013 Synopsys, Inc. (www.synopsys.com)
*
* Licensed under the LGPL v2.1 or later, see the file COPYING.LIB in this tarball.
*/
#include <sys/syscall.h>
#include <sysdep.h>
/* No legacy syscall ABI means NR_vfork is not available at all, use clone */
#define _SIGNAL_H
#include <bits/signum.h> /* For SIGCHLD */
#define CLONE_VM 0x00000100
#define CLONE_VFORK 0x00004000
#define CLONE_FLAGS_FOR_VFORK (CLONE_VM|CLONE_VFORK|SIGCHLD)
ENTRY(__vfork)
#ifdef SAVE_PID
THREAD_SELF r1 ; Get to struct pthread (just before TCB)
ld r2, [r1, PTHREAD_PID]
neg.f r3, r2
bset.z r3, r3, 31
st r3, [r1, PTHREAD_PID]
#endif
mov r0, CLONE_FLAGS_FOR_VFORK
mov_s r1, sp
mov r8, __NR_clone
ARC_TRAP_INSN
cmp r0, 0
#ifdef RESTORE_PID
bz 1f ; child continues
THREAD_SELF r1 ; Get to struct pthread (just before TCB)
st r2, [r1, PTHREAD_PID]
1:
#endif
jge [blink] ; pid >=0 return, else detour via tailcall to errno
b __syscall_error
END(__vfork)
weak_alias(__vfork,vfork)
libc_hidden_def(vfork)
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