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+/*
+ * Based on arch/arm/lib/memchr.S
+ *
+ * Copyright (C) 1995-2000 Russell King
+ * Copyright (C) 2013 ARM Ltd.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/linkage.h>
+#include <asm/assembler.h>
+
+/*
+ * Find a character in an area of memory.
+ *
+ * Parameters:
+ * x0 - buf
+ * x1 - c
+ * x2 - n
+ * Returns:
+ * x0 - address of first occurrence of 'c' or 0
+ */
+ENTRY(memchr)
+ and w1, w1, #0xff
+1: subs x2, x2, #1
+ b.mi 2f
+ ldrb w3, [x0], #1
+ cmp w3, w1
+ b.ne 1b
+ sub x0, x0, #1
+ ret
+2: mov x0, #0
+ ret
+ENDPROC(memchr)