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-rw-r--r--kernel/arch/avr32/lib/memset.S72
1 files changed, 72 insertions, 0 deletions
diff --git a/kernel/arch/avr32/lib/memset.S b/kernel/arch/avr32/lib/memset.S
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+++ b/kernel/arch/avr32/lib/memset.S
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+/*
+ * Copyright (C) 2004-2006 Atmel Corporation
+ *
+ * Based on linux/arch/arm/lib/memset.S
+ * Copyright (C) 1995-2000 Russell King
+ *
+ * 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.
+ *
+ * ASM optimised string functions
+ */
+#include <asm/asm.h>
+
+ /*
+ * r12: void *b
+ * r11: int c
+ * r10: size_t len
+ *
+ * Returns b in r12
+ */
+ .text
+ .global memset
+ .type memset, @function
+ .align 5
+memset:
+ mov r9, r12
+ mov r8, r12
+ or r11, r11, r11 << 8
+ andl r9, 3, COH
+ brne 1f
+
+2: or r11, r11, r11 << 16
+ sub r10, 4
+ brlt 5f
+
+ /* Let's do some real work */
+4: st.w r8++, r11
+ sub r10, 4
+ brge 4b
+
+ /*
+ * When we get here, we've got less than 4 bytes to set. r10
+ * might be negative.
+ */
+5: sub r10, -4
+ reteq r12
+
+ /* Fastpath ends here, exactly 32 bytes from memset */
+
+ /* Handle unaligned count or pointer */
+ bld r10, 1
+ brcc 6f
+ st.b r8++, r11
+ st.b r8++, r11
+ bld r10, 0
+ retcc r12
+6: st.b r8++, r11
+ retal r12
+
+ /* Handle unaligned pointer */
+1: sub r10, 4
+ brlt 5b
+ add r10, r9
+ lsl r9, 1
+ add pc, r9
+ st.b r8++, r11
+ st.b r8++, r11
+ st.b r8++, r11
+ rjmp 2b
+
+ .size memset, . - memset