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/*
* Copyright (C) 2008-2010 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 <machine/asm.h>
#include <sys/linux-syscalls.h>
// int __pthread_clone(void* (*fn)(void*), void* child_stack, int flags, void* arg);
ENTRY(__pthread_clone)
# Copy the args onto the new stack.
stmdb r1!, {r0, r3}
# The sys_clone system call only takes two arguments: 'flags' and 'child_stack'.
# 'child_stack' is already in r1, but we need to move 'flags' into position.
mov r0, r2
stmfd sp!, {r4, r7}
# System call.
ldr r7, =__NR_clone
swi #0
movs r0, r0
beq 1f
# In parent, reload saved registers then either exit or set errno.
ldmfd sp!, {r4, r7}
bxpl lr
b __set_syscall_errno
1: # The child.
# pick the function arg and call address off the stack and jump
# to the C __thread_entry function which does some setup and then
# calls the thread's start function
pop {r0, r1}
# __thread_entry needs the TLS pointer
mov r2, sp
b __thread_entry
END(__pthread_clone)
#
# This function is defined as:
#
# pid_t __bionic_clone( int flags, void *child_stack,
# pid_t *pid, void *tls, pid_t *ctid,
# int (*fn)(void *), void* arg );
#
# NOTE: This is not the same signature as the glibc
# __clone function. Placing 'fn' and 'arg'
# at the end of the parameter list makes the
# implementation much simpler.
#
ENTRY(__bionic_clone)
mov ip, sp
.save {r4, r5, r6, r7}
# save registers to parent stack
stmfd sp!, {r4, r5, r6, r7}
# load extra parameters
ldmfd ip, {r4, r5, r6}
# store 'fn' and 'arg' to the child stack
str r5, [r1, #-4]
str r6, [r1, #-8]
# System call
ldr r7, =__NR_clone
swi #0
movs r0, r0
beq 1f
# In the parent, reload saved registers then either exit or set errno.
ldmfd sp!, {r4, r5, r6, r7}
bxpl lr
b __set_syscall_errno
1: # The child.
ldr r0, [sp, #-4]
ldr r1, [sp, #-8]
b __bionic_clone_entry
END(__bionic_clone)
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