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/* ffsll -- find first set bit in a long long, from least significant end.
Copyright (C) 2013-2024 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library. If not, see
<https://www.gnu.org/licenses/>. */
#include <sysdep.h>
.syntax unified
.text
ENTRY (ffsll)
@ If low part is 0, operate on the high part. Ensure that the
@ word on which we operate is in r0. Set r2 to the bit offset
@ of the word being considered. Set the flags for the word
@ being operated on.
#ifdef __ARMEL__
cmp r0, #0
itee ne
movne r2, #0
moveq r2, #32
movseq r0, r1
#else
cmp r1, #0
ittee ne
movne r2, #0
movne r0, r1
moveq r2, #32
cmpeq r0, #0
#endif
@ Perform the ffs on r0.
rbit r0, r0
ittt ne
clzne r0, r0
addne r2, r2, #1
addne r0, r0, r2
bx lr
END (ffsll)
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