1/*- 2 * Copyright (c) 2000 Doug Rabson 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 */ 26 27#include <machine/asm.h> 28__FBSDID("$FreeBSD$"); 29 30ENTRY(bzero, 2) 31 32 cmp.le p6,p0=in1,r0 // bail if len <= 0 33(p6) br.ret.spnt.few rp 34 ;; 35 mov r14=ar.lc // save ar.lc 36 37 cmp.ltu p6,p0=17,in1 // check for small 38(p6) br.dptk.few 3f 39 401: add r15=-1,in1 ;; 41 mov ar.lc=r15 ;; 422: st1 [in0]=r0,1 // zero one byte 43 br.cloop.sptk.few 2b // loop 44 45 ;; 46 mov ar.lc=r14 // done 47 br.ret.sptk.few rp 48 49 // Zero up to 8byte alignment 50 513: tbit.nz p6,p0=in0,0 ;; 52(p6) st1 [in0]=r0,1 53(p6) add in1=-1,in1 ;; 54 55 tbit.nz p6,p0=in0,1 ;; 56(p6) st2 [in0]=r0,2 57(p6) add in1=-2,in1 ;; 58 59 tbit.nz p6,p0=in0,2 ;; 60(p6) st4 [in0]=r0,4 61(p6) add in1=-4,in1 62 63 ;; 64 shr.u r15=in1,3 // word count 65 extr.u in1=in1,0,3 ;; // trailing bytes 66 cmp.eq p6,p0=r15,r0 // check for zero 67 cmp.ne p7,p0=in1,r0 68(p6) br.dpnt.few 1b // zero last bytes 69 70 add r15=-1,r15 ;; 71 mov ar.lc=r15 ;; 724: st8 [in0]=r0,8 73 br.cloop.sptk.few 4b 74 75(p7) br.dpnt.few 1b // zero last bytes 76 77 ;; 78 mov ar.lc=r14 // done 79 br.ret.sptk.few rp 80 81END(bzero) 82