diff options
Diffstat (limited to 'arch/avr32/lib/memcpy.S')
-rw-r--r-- | arch/avr32/lib/memcpy.S | 62 |
1 files changed, 62 insertions, 0 deletions
diff --git a/arch/avr32/lib/memcpy.S b/arch/avr32/lib/memcpy.S new file mode 100644 index 000000000000..0abb26142b64 --- /dev/null +++ b/arch/avr32/lib/memcpy.S | |||
@@ -0,0 +1,62 @@ | |||
1 | /* | ||
2 | * Copyright (C) 2004-2006 Atmel Corporation | ||
3 | * | ||
4 | * This program is free software; you can redistribute it and/or modify | ||
5 | * it under the terms of the GNU General Public License version 2 as | ||
6 | * published by the Free Software Foundation. | ||
7 | */ | ||
8 | |||
9 | /* | ||
10 | * void *memcpy(void *to, const void *from, unsigned long n) | ||
11 | * | ||
12 | * This implementation does word-aligned loads in the main loop, | ||
13 | * possibly sacrificing alignment of stores. | ||
14 | * | ||
15 | * Hopefully, in most cases, both "to" and "from" will be | ||
16 | * word-aligned to begin with. | ||
17 | */ | ||
18 | .text | ||
19 | .global memcpy | ||
20 | .type memcpy, @function | ||
21 | memcpy: | ||
22 | mov r9, r11 | ||
23 | andl r9, 3, COH | ||
24 | brne 1f | ||
25 | |||
26 | /* At this point, "from" is word-aligned */ | ||
27 | 2: sub r10, 4 | ||
28 | mov r9, r12 | ||
29 | brlt 4f | ||
30 | |||
31 | 3: ld.w r8, r11++ | ||
32 | sub r10, 4 | ||
33 | st.w r12++, r8 | ||
34 | brge 3b | ||
35 | |||
36 | 4: neg r10 | ||
37 | reteq r9 | ||
38 | |||
39 | /* Handle unaligned count */ | ||
40 | lsl r10, 2 | ||
41 | add pc, pc, r10 | ||
42 | ld.ub r8, r11++ | ||
43 | st.b r12++, r8 | ||
44 | ld.ub r8, r11++ | ||
45 | st.b r12++, r8 | ||
46 | ld.ub r8, r11++ | ||
47 | st.b r12++, r8 | ||
48 | retal r9 | ||
49 | |||
50 | /* Handle unaligned "from" pointer */ | ||
51 | 1: sub r10, 4 | ||
52 | brlt 4b | ||
53 | add r10, r9 | ||
54 | lsl r9, 2 | ||
55 | add pc, pc, r9 | ||
56 | ld.ub r8, r11++ | ||
57 | st.b r12++, r8 | ||
58 | ld.ub r8, r11++ | ||
59 | st.b r12++, r8 | ||
60 | ld.ub r8, r11++ | ||
61 | st.b r12++, r8 | ||
62 | rjmp 2b | ||