Commit | Line | Data |
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5f97f7f9 HS |
1 | /* |
2 | * Copyright (C) 2004-2006 Atmel Corporation | |
3 | * | |
4 | * Based on linux/arch/arm/lib/memset.S | |
5 | * Copyright (C) 1995-2000 Russell King | |
6 | * | |
7 | * This program is free software; you can redistribute it and/or modify | |
8 | * it under the terms of the GNU General Public License version 2 as | |
9 | * published by the Free Software Foundation. | |
10 | * | |
11 | * ASM optimised string functions | |
12 | */ | |
13 | #include <asm/asm.h> | |
14 | ||
15 | /* | |
16 | * r12: void *b | |
17 | * r11: int c | |
18 | * r10: size_t len | |
19 | * | |
20 | * Returns b in r12 | |
21 | */ | |
22 | .text | |
23 | .global memset | |
24 | .type memset, @function | |
25 | .align 5 | |
26 | memset: | |
27 | mov r9, r12 | |
28 | mov r8, r12 | |
29 | or r11, r11, r11 << 8 | |
30 | andl r9, 3, COH | |
31 | brne 1f | |
32 | ||
33 | 2: or r11, r11, r11 << 16 | |
34 | sub r10, 4 | |
35 | brlt 5f | |
36 | ||
37 | /* Let's do some real work */ | |
38 | 4: st.w r8++, r11 | |
39 | sub r10, 4 | |
40 | brge 4b | |
41 | ||
42 | /* | |
43 | * When we get here, we've got less than 4 bytes to set. r10 | |
44 | * might be negative. | |
45 | */ | |
46 | 5: sub r10, -4 | |
47 | reteq r12 | |
48 | ||
49 | /* Fastpath ends here, exactly 32 bytes from memset */ | |
50 | ||
51 | /* Handle unaligned count or pointer */ | |
52 | bld r10, 1 | |
53 | brcc 6f | |
54 | st.b r8++, r11 | |
55 | st.b r8++, r11 | |
56 | bld r10, 0 | |
57 | retcc r12 | |
58 | 6: st.b r8++, r11 | |
59 | retal r12 | |
60 | ||
61 | /* Handle unaligned pointer */ | |
62 | 1: sub r10, 4 | |
63 | brlt 5b | |
64 | add r10, r9 | |
65 | lsl r9, 1 | |
66 | add pc, r9 | |
67 | st.b r8++, r11 | |
68 | st.b r8++, r11 | |
69 | st.b r8++, r11 | |
70 | rjmp 2b | |
71 | ||
72 | .size memset, . - memset |