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-rw-r--r--arch/arm64/lib/strchr.S32
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diff --git a/arch/arm64/lib/strchr.S b/arch/arm64/lib/strchr.S
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+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Based on arch/arm/lib/strchr.S
+ *
+ * Copyright (C) 1995-2000 Russell King
+ * Copyright (C) 2013 ARM Ltd.
+ */
+
+#include <linux/linkage.h>
+#include <asm/assembler.h>
+
+/*
+ * Find the first occurrence of a character in a string.
+ *
+ * Parameters:
+ * x0 - str
+ * x1 - c
+ * Returns:
+ * x0 - address of first occurrence of 'c' or 0
+ */
+SYM_FUNC_START_WEAK(strchr)
+ and w1, w1, #0xff
+1: ldrb w2, [x0], #1
+ cmp w2, w1
+ ccmp w2, wzr, #4, ne
+ b.ne 1b
+ sub x0, x0, #1
+ cmp w2, w1
+ csel x0, x0, xzr, eq
+ ret
+SYM_FUNC_END(strchr)
+EXPORT_SYMBOL_NOKASAN(strchr)