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/*-
* Copyright (c) 2000 Doug Rabson
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. 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 AUTHOR 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 AUTHOR 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>
__FBSDID("$FreeBSD$");
ENTRY(bzero, 2)
cmp.le p6,p0=in1,r0 // bail if len <= 0
(p6) br.ret.spnt.few rp
;;
mov r14=ar.lc // save ar.lc
cmp.ltu p6,p0=17,in1 // check for small
(p6) br.dptk.few 3f
1: add r15=-1,in1 ;;
mov ar.lc=r15 ;;
2: st1 [in0]=r0,1 // zero one byte
br.cloop.sptk.few 2b // loop
;;
mov ar.lc=r14 // done
br.ret.sptk.few rp
// Zero up to 8byte alignment
3: tbit.nz p6,p0=in0,0 ;;
(p6) st1 [in0]=r0,1
(p6) add in1=-1,in1 ;;
tbit.nz p6,p0=in0,1 ;;
(p6) st2 [in0]=r0,2
(p6) add in1=-2,in1 ;;
tbit.nz p6,p0=in0,2 ;;
(p6) st4 [in0]=r0,4
(p6) add in1=-4,in1
;;
shr.u r15=in1,3 // word count
extr.u in1=in1,0,3 ;; // trailing bytes
cmp.eq p6,p0=r15,r0 // check for zero
cmp.ne p7,p0=in1,r0
(p6) br.dpnt.few 1b // zero last bytes
add r15=-1,r15 ;;
mov ar.lc=r15 ;;
4: st8 [in0]=r0,8
br.cloop.sptk.few 4b
(p7) br.dpnt.few 1b // zero last bytes
;;
mov ar.lc=r14 // done
br.ret.sptk.few rp
END(bzero)
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