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-rw-r--r--ports/sysdeps/ia64/strchr.S111
1 files changed, 111 insertions, 0 deletions
diff --git a/ports/sysdeps/ia64/strchr.S b/ports/sysdeps/ia64/strchr.S
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+++ b/ports/sysdeps/ia64/strchr.S
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+/* Optimized version of the standard strchr() function.
+   This file is part of the GNU C Library.
+   Copyright (C) 2000, 2001, 2003 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 Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 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
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+/* Return: the address of the first occurence of chr in str or NULL
+
+   Inputs:
+        in0:    str
+        in1:    chr
+
+   A modified version of memchr.S, the search ends when the character is
+   found or the terminating null character is encountered.
+
+   This implementation assumes little endian mode.  For big endian mode,
+   the instruction czx1.r should be replaced by czx1.l.  */
+
+#include <sysdep.h>
+#undef ret
+
+#define saved_lc	r18
+#define poschr		r19
+#define pos0		r20
+#define val1		r21
+#define val2		r22
+#define tmp		r24
+#define chrx8		r25
+#define loopcnt		r30
+
+#define str		in0
+#define chr		in1
+
+ENTRY(strchr)
+	.prologue
+	alloc r2 = ar.pfs, 2, 0, 0, 0
+	.save ar.lc, saved_lc
+        mov 	saved_lc = ar.lc 	// save the loop counter
+	.body
+	mov 	ret0 = str
+	and 	tmp = 7, str		// tmp = str % 8
+	mux1	chrx8 = chr, @brcst
+	extr.u	chr = chr, 0, 8		// retain only the last byte
+	cmp.ne	p8, p0 = r0, r0		// clear p8
+	;;
+	sub	loopcnt = 8, tmp	// loopcnt = 8 - tmp
+	cmp.eq	p6, p0 = tmp, r0
+(p6)	br.cond.sptk	.str_aligned;;
+	adds	loopcnt = -1, loopcnt;;
+	mov	ar.lc = loopcnt
+.l1:
+	ld1	val2 = [ret0], 1
+	;;
+	cmp.eq	p6, p0 = val2, chr
+	cmp.eq	p7, p0 = val2, r0
+(p6)	br.cond.spnt	.restore_and_exit
+(p7)	br.cond.spnt	.notfound
+	br.cloop.sptk	.l1
+.str_aligned:
+	ld8	val1 = [ret0], 8;;
+	nop.b	0
+	nop.b 	0
+.l2:
+	ld8.s	val2 = [ret0], 8	// don't bomb out here
+	czx1.r	pos0 = val1
+	xor	tmp = val1, chrx8	// if val1 contains chr, tmp will
+	;;				// contain a zero in its position
+	czx1.r	poschr = tmp
+	cmp.ne	p6, p0 = 8, pos0
+	;;
+	cmp.ne	p7, p0 = 8, poschr
+(p7)	br.cond.spnt .foundit
+(p6)	br.cond.spnt .notfound
+	chk.s	val2, .recovery
+.back:
+	mov	val1 = val2
+	br.cond.dptk .l2
+.foundit:
+(p6)	cmp.lt	p8, p0 = pos0, poschr	// we found chr and null in the word
+(p8)	br.cond.spnt .notfound		// null was found before chr
+	add	ret0 = ret0, poschr ;;
+	adds	ret0 = -15, ret0 ;;	// should be -16, but we decrement
+.restore_and_exit:			// ret0 in the next instruction
+	adds	ret0 = -1, ret0		// ret0 was pointing 1 char too far
+	mov 	ar.lc = saved_lc	// restore the loop counter
+	br.ret.sptk.many b0
+.notfound:
+	mov	ret0 = r0		// return NULL if null was found
+	mov 	ar.lc = saved_lc
+	br.ret.sptk.many b0
+.recovery:
+	adds	ret0 = -8, ret0;;
+	ld8	val2 = [ret0], 8	// bomb out here
+	br.cond.sptk	.back
+END(strchr)
+
+weak_alias (strchr, index)
+libc_hidden_builtin_def (strchr)