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+/*-
+ * Copyright (c) 1990 The Regents of the University of California.
+ * 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.
+ * 3. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *	This product includes software developed by the University of
+ *	California, Berkeley and its contributors.
+ * 4. Neither the name of the University nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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.
+ */
+
+#if defined(LIBC_SCCS) && !defined(lint)
+	.asciz "@(#)memchr.s	5.1 (Berkeley) 5/29/90"
+#endif /* LIBC_SCCS and not lint */
+
+/*
+ * Find the first occurence of c in the memory at cp (length n).
+ * Return pointer to match or null pointer.
+ *
+ * This code optimises the usual case (0 < n < 65535).
+ *
+ * void *
+ * memchr(cp, c, n)
+ *	char *cp, c;
+ *	size_t n;
+ */
+
+#include "DEFS.h"
+
+ENTRY(memchr, 0)
+	movq	4(ap),r1	# r1 = cp; r2 = c
+	movl	12(ap),r0	# r0 = n
+	movzwl	$65535,r4	# handy constant
+0:
+	cmpl	r0,r4		# check for annoying locc limit
+	bgtru	3f
+
+	/* n <= 65535 */
+	locc	r2,r0,(r1)	# search n bytes for c
+	beql	2f		# done if not found (r0 already 0)
+1:	/* found character c at (r1) */
+	movl	r1,r0
+2:
+	ret
+
+3:	/* n > 65535 */
+	locc	r2,r4,(r1)	# search 65535 bytes for c
+	beql	1b		# done if found
+	decw	r0		# from 0 to 65535
+	subl2	r0,r4		# adjust n
+	brb	0b		# and loop