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+/*
+ * Copyright (c) 1988 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 "@(#)strrchr.s	5.4 (Berkeley) 6/1/90"
+#endif /* LIBC_SCCS and not lint */
+
+/*
+ * Find the last occurence of c in the string cp.
+ * Return pointer to match or null pointer.
+ *
+ * char *
+ * strrchr(cp, c)
+ *	char *cp, c;
+ */
+#include "DEFS.h"
+
+	.lcomm	tbl,256
+
+ENTRY(strrchr, 0)
+	movzwl	$65535,r4	/* handy 65535 */
+	movq	4(ap),r1	/* r1 = cp; r2 = c */
+	movzbl	r2,r2
+	beql	Lzero		/* special case for c == '\0' */
+
+	clrl	r5		/* r5 = pointer to last match */
+
+/*
+ * Fancy scanc version.  Alas, it is not reentrant.
+ */
+	movab	tbl,r3		/* r3 = address of table */
+	bbss	$0,(r3),Lreent	/* ensure not reentering */
+	movab	(r3)[r2],r4
+	incb	(r4)		/* mark both '\0' and c */
+0:
+	scanc	$65535,(r1),(r3),$1	/* look for c or '\0' */
+	beql	0b		/* keep looking */
+	tstb	(r1)
+	beql	1f		/* done if '\0' */
+	movab	(r1)+,r5	/* save most recently found, and skip over it */
+	jbr	0b		/* keep looking */
+1:
+	movl	r5,r0		/* return last found (if any) */
+	clrb	(r4)		/* clean up table */
+	clrb	(r3)
+	ret
+
+/*
+ * Special case for \0.
+ */
+Lzero:
+	locc	$0,r4,(r1)	/* just find end of string */
+	beql	Lzero		/* still looking */
+	movl	r1,r0		/* found it */
+	ret
+
+/*
+ * Slower reentrant version is two two-step searches.  The first
+ * phase runs until we know where the string ends; it locates any
+ * occurrences of c within a 65535-byte block.  Once we have found
+ * the end of the string, we find any further occurrences before
+ * that location.
+ */
+Lreent:
+0:	/* first phase */
+	movl	r1,r3
+	locc	$0,r4,(r3)	/* look for '\0' */
+	bneq	1f
+	locc	r2,r4,(r3)	/* continue phase 1 search for c */
+	beql	0b
+	movab	(r1)+,r5	/* found c: save and increment pointer */
+	brb	0b		/* and continue */
+
+1:	/* second phase */
+	subl3	r3,r1,r0	/* length of short block */
+	movl	r3,r1
+2:
+	locc	r2,r0,(r1)	/* look for c */
+	beql	3f		/* skip if not found */
+	movab	(r1)+,r5	/* save pointer as before */
+	sobgtr	r0,2b		/* adjust count and loop */
+3:
+	movl	r5,r0		/* return stashed pointer */
+	ret