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#include <dietfeatures.h>
#include "syscalls.h"
#include <errno.h>
.text
.weak clone
clone:
.global __clone
__clone:
cmpwi 4,0 /* check have non null child_stack pointer */
cmpwi cr1, 3,0 /* check have non null thread_funcion */
cror eq,4*cr1+eq,eq /* now if eq is set one is or both are zero */
beq .Lclone_error
stwu 1,-32(1) /* alloc some space on the stack */
stmw 29, 16(1) /* save r29,r30,r31 on stack */
rlwinm 4,4,0,0,27 /* mask out lower 4 bits */
/* move parameter to positions clone wants them */
mr 29,3 /* r29 = r3 fn */
mr 30,4 /* r30 = r4 stack */
mr 31,6 /* r31 = r6 arg */
mr 3, 5 /* r3 = r5 flags */
li 0, __NR_clone /* load syscall nr. */
sc
cmpwi cr1,3,0 /* compare return of syscall with 0 */
crandc 4*cr1+eq,4*cr1+eq,so
bne .Lclone_parent /* return was non zero -> .Lclone_parent */
/* we are the cloned process */
mr 1, 30 /* set stack pointer */
mtctr 29 /* set count register to fn ? */
mr 3, 31 /* set argument */
bctrl /* branch trough count register and link */
b _exit /* exit thread */
.Lclone_parent:
lmw 29,16(1) /* restore saved registers */
addi 1, 1,32 /* free stack */
bnslr+ /* had cloned a thread so return to parent */
b error_unified_syscall
.Lclone_error:
li 3, EINVAL
b error_unified_syscall
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