diff options
Diffstat (limited to 'kernel/arch/avr32/lib/memset.S')
| -rw-r--r-- | kernel/arch/avr32/lib/memset.S | 72 |
1 files changed, 72 insertions, 0 deletions
diff --git a/kernel/arch/avr32/lib/memset.S b/kernel/arch/avr32/lib/memset.S new file mode 100644 index 000000000..40da32c04 --- /dev/null +++ b/kernel/arch/avr32/lib/memset.S @@ -0,0 +1,72 @@ +/* + * 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 |