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5210d1e6 VG |
1 | /* |
2 | * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com) | |
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 | /* If dst and src are 4 byte aligned, copy 8 bytes at a time. | |
10 | If the src is 4, but not 8 byte aligned, we first read 4 bytes to get | |
11 | it 8 byte aligned. Thus, we can do a little read-ahead, without | |
12 | dereferencing a cache line that we should not touch. | |
13 | Note that short and long instructions have been scheduled to avoid | |
14 | branch stalls. | |
15 | The beq_s to r3z could be made unaligned & long to avoid a stall | |
16 | there, but the it is not likely to be taken often, and it | |
17 | would also be likey to cost an unaligned mispredict at the next call. */ | |
18 | ||
ec7ac6af | 19 | #include <linux/linkage.h> |
5210d1e6 | 20 | |
ec7ac6af | 21 | ENTRY(strcpy) |
5210d1e6 VG |
22 | or r2,r0,r1 |
23 | bmsk_s r2,r2,1 | |
24 | brne.d r2,0,charloop | |
25 | mov_s r10,r0 | |
26 | ld_s r3,[r1,0] | |
27 | mov r8,0x01010101 | |
28 | bbit0.d r1,2,loop_start | |
29 | ror r12,r8 | |
30 | sub r2,r3,r8 | |
31 | bic_s r2,r2,r3 | |
32 | tst_s r2,r12 | |
33 | bne r3z | |
34 | mov_s r4,r3 | |
35 | .balign 4 | |
36 | loop: | |
37 | ld.a r3,[r1,4] | |
38 | st.ab r4,[r10,4] | |
39 | loop_start: | |
40 | ld.a r4,[r1,4] | |
41 | sub r2,r3,r8 | |
42 | bic_s r2,r2,r3 | |
43 | tst_s r2,r12 | |
44 | bne_s r3z | |
45 | st.ab r3,[r10,4] | |
46 | sub r2,r4,r8 | |
47 | bic r2,r2,r4 | |
48 | tst r2,r12 | |
49 | beq loop | |
50 | mov_s r3,r4 | |
51 | #ifdef __LITTLE_ENDIAN__ | |
52 | r3z: bmsk.f r1,r3,7 | |
53 | lsr_s r3,r3,8 | |
54 | #else | |
55 | r3z: lsr.f r1,r3,24 | |
56 | asl_s r3,r3,8 | |
57 | #endif | |
58 | bne.d r3z | |
59 | stb.ab r1,[r10,1] | |
60 | j_s [blink] | |
61 | ||
62 | .balign 4 | |
63 | charloop: | |
64 | ldb.ab r3,[r1,1] | |
65 | ||
66 | ||
67 | brne.d r3,0,charloop | |
68 | stb.ab r3,[r10,1] | |
69 | j [blink] | |
ec7ac6af | 70 | END(strcpy) |