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/*
* Copyright (C) 2008 The Android Open Source Project
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <private/bionic_asm.h>
// pid_t __bionic_clone(int flags, void* child_stack, pid_t* parent_tid, void* tls, pid_t* child_tid, int (*fn)(void*), void* arg);
ENTRY_PRIVATE(__bionic_clone)
mov ip, sp
# save registers to parent stack
stmfd sp!, {r4, r5, r6, r7}
.cfi_def_cfa_offset 16
.cfi_rel_offset r4, 0
.cfi_rel_offset r5, 4
.cfi_rel_offset r6, 8
.cfi_rel_offset r7, 12
# load extra parameters
ldmfd ip, {r4, r5, r6}
# Push 'fn' and 'arg' onto the child stack.
stmdb r1!, {r5, r6}
# Make the system call.
ldr r7, =__NR_clone
swi #0
# Are we the child?
movs r0, r0
beq .L_bc_child
# In the parent, reload saved registers then either return or set errno.
ldmfd sp!, {r4, r5, r6, r7}
cmn r0, #(MAX_ERRNO + 1)
bxls lr
neg r0, r0
b __set_errno_internal
.L_bc_child:
# We're in the child now. Set the end of the frame record chain.
mov fp, #0
# Setting lr to 0 will make the unwinder stop at __start_thread.
mov lr, #0
# Call __start_thread with the 'fn' and 'arg' we stored on the child stack.
pop {r0, r1}
b __start_thread
END(__bionic_clone)
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