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-rw-r--r--sysdeps/ia64/bzero.S94
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diff --git a/sysdeps/ia64/bzero.S b/sysdeps/ia64/bzero.S
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+/* Optimized version of the standard bzero() function.
+   This file is part of the GNU C Library.
+   Copyright (C) 2000, 2001 Free Software Foundation, Inc.
+   Contributed by Dan Pop <Dan.Pop@cern.ch>.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Library General Public License as
+   published by the Free Software Foundation; either version 2 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
+   Library General Public License for more details.
+
+   You should have received a copy of the GNU Library General Public
+   License along with the GNU C Library; see the file COPYING.LIB.  If not,
+   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.  */
+
+/* Return: dest
+  
+   Inputs:
+        in0:    dest
+        in1:    count
+
+   The algorithm is fairly straightforward: set byte by byte until we
+   we get to a word aligned address, then set word by word as much as
+   possible; the remaining few bytes are set one by one.  */
+
+#include <sysdep.h>
+#undef ret
+
+#define dest		in0
+#define	cnt		in1
+
+#define save_pfs 	loc0
+#define ptr1		loc1
+#define ptr2		loc2
+#define tmp		loc3
+#define	loopcnt		loc4
+#define save_lc		loc5
+
+ENTRY(bzero)
+	.prologue
+	alloc	save_pfs = ar.pfs, 2, 6, 0, 0	
+	.save ar.lc, save_lc
+	mov	save_lc = ar.lc
+	.body
+	mov	ret0 = dest
+	and	tmp = 7, dest
+	cmp.eq	p6, p0 = cnt, r0
+(p6)	br.cond.spnt .restore_and_exit ;;
+	mov	ptr1 = dest
+	sub	loopcnt = 8, tmp
+	cmp.gt	p6, p0 = 16, cnt
+(p6)	br.cond.spnt .set_few;;
+	cmp.eq	p6, p0 = tmp, r0
+(p6)	br.cond.sptk .dest_aligned
+	sub	cnt = cnt, loopcnt
+	adds	loopcnt = -1, loopcnt;;
+	mov	ar.lc = loopcnt;;	
+.l1:
+	st1	[ptr1] = r0, 1
+	br.cloop.dptk	.l1 ;;
+.dest_aligned:
+	adds	ptr2 = 8, ptr1
+	shr.u	loopcnt = cnt, 4 ;;	// loopcnt = cnt / 16
+	cmp.eq	p6, p0 = loopcnt, r0
+(p6)	br.cond.spnt	.one_more
+	and	cnt = 0xf, cnt		// compute the remaining cnt
+	adds	loopcnt = -1, loopcnt;;
+	mov     ar.lc = loopcnt;;	
+.l2:
+	st8	[ptr1] = r0, 16
+	st8	[ptr2] = r0, 16
+	br.cloop.dptk .l2
+	cmp.le	p6, p0 = 8, cnt	;;
+.one_more:
+(p6)	st8     [ptr1] = r0, 8
+(p6)	adds	cnt = -8, cnt ;;
+	cmp.eq	p6, p0 = cnt, r0
+(p6)	br.cond.spnt	.restore_and_exit
+.set_few:
+	adds	loopcnt = -1, cnt;;
+	mov	ar.lc = loopcnt;;
+.l3:	
+	st1     [ptr1] = r0, 1
+	br.cloop.dptk   .l3 ;;	
+.restore_and_exit:
+	mov	ar.lc = save_lc
+	mov	ar.pfs = save_pfs
+	br.ret.sptk.many b0					
+END(bzero)