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#------------------------------------------------------------------------------
#
# Copyright (c) 2008 - 2010, Apple Inc. All rights reserved.<BR>
#
# This program and the accompanying materials
# are licensed and made available under the terms and conditions of the BSD License
# which accompanies this distribution. The full text of the license may be found at
# http://opensource.org/licenses/bsd-license.php
#
# THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
# WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
#
#------------------------------------------------------------------------------
.text
.align 2
GCC_ASM_EXPORT(__ctzsi2)
ASM_PFX(__ctzsi2):
uxth r3, r0
cmp r3, #0
moveq ip, #16
movne ip, #0
@ lr needed for prologue
mov r0, r0, lsr ip
tst r0, #255
movne r3, #0
moveq r3, #8
mov r0, r0, lsr r3
tst r0, #15
movne r1, #0
moveq r1, #4
add r3, r3, ip
mov r0, r0, lsr r1
tst r0, #3
movne r2, #0
moveq r2, #2
add r3, r3, r1
mov r0, r0, lsr r2
and r0, r0, #3
add r2, r3, r2
eor r3, r0, #1
mov r0, r0, lsr #1
ands r3, r3, #1
mvnne r3, #0
rsb r0, r0, #2
and r0, r3, r0
add r0, r2, r0
bx lr
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