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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
	.globl ASM_PFX(__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