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Diffstat (limited to 'arch/blackfin/lib/memmove.S')
-rw-r--r-- | arch/blackfin/lib/memmove.S | 103 |
1 files changed, 103 insertions, 0 deletions
diff --git a/arch/blackfin/lib/memmove.S b/arch/blackfin/lib/memmove.S new file mode 100644 index 000000000000..2e5fb7f8df13 --- /dev/null +++ b/arch/blackfin/lib/memmove.S | |||
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1 | /* | ||
2 | * File: arch/blackfin/lib/memmove.S | ||
3 | * Based on: | ||
4 | * Author: | ||
5 | * | ||
6 | * Created: | ||
7 | * Description: | ||
8 | * | ||
9 | * Modified: | ||
10 | * Copyright 2004-2006 Analog Devices Inc. | ||
11 | * | ||
12 | * Bugs: Enter bugs at http://blackfin.uclinux.org/ | ||
13 | * | ||
14 | * This program is free software; you can redistribute it and/or modify | ||
15 | * it under the terms of the GNU General Public License as published by | ||
16 | * the Free Software Foundation; either version 2 of the License, or | ||
17 | * (at your option) any later version. | ||
18 | * | ||
19 | * This program is distributed in the hope that it will be useful, | ||
20 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | ||
21 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | ||
22 | * GNU General Public License for more details. | ||
23 | * | ||
24 | * You should have received a copy of the GNU General Public License | ||
25 | * along with this program; if not, see the file COPYING, or write | ||
26 | * to the Free Software Foundation, Inc., | ||
27 | * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA | ||
28 | */ | ||
29 | |||
30 | #include <linux/linkage.h> | ||
31 | |||
32 | .align 2 | ||
33 | |||
34 | /* | ||
35 | * C Library function MEMMOVE | ||
36 | * R0 = To Address (leave unchanged to form result) | ||
37 | * R1 = From Address | ||
38 | * R2 = count | ||
39 | * Data may overlap | ||
40 | */ | ||
41 | |||
42 | ENTRY(_memmove) | ||
43 | I1 = P3; | ||
44 | P0 = R0; /* P0 = To address */ | ||
45 | P3 = R1; /* P3 = From Address */ | ||
46 | P2 = R2; /* P2 = count */ | ||
47 | CC = P2 == 0; /* Check zero count*/ | ||
48 | IF CC JUMP .Lfinished; /* very unlikely */ | ||
49 | |||
50 | CC = R1 < R0 (IU); /* From < To */ | ||
51 | IF !CC JUMP .Lno_overlap; | ||
52 | R3 = R1 + R2; | ||
53 | CC = R0 <= R3 (IU); /* (From+len) >= To */ | ||
54 | IF CC JUMP .Loverlap; | ||
55 | .Lno_overlap: | ||
56 | R3 = 11; | ||
57 | CC = R2 <= R3; | ||
58 | IF CC JUMP .Lbytes; | ||
59 | R3 = R1 | R0; /* OR addresses together */ | ||
60 | R3 <<= 30; /* check bottom two bits */ | ||
61 | CC = AZ; /* AZ set if zero.*/ | ||
62 | IF !CC JUMP .Lbytes; /* Jump if addrs not aligned.*/ | ||
63 | |||
64 | I0 = P3; | ||
65 | P1 = P2 >> 2; /* count = n/4 */ | ||
66 | P1 += -1; | ||
67 | R3 = 3; | ||
68 | R2 = R2 & R3; /* remainder */ | ||
69 | P2 = R2; /* set remainder */ | ||
70 | R1 = [I0++]; | ||
71 | |||
72 | LSETUP (.Lquad_loop, .Lquad_loop) LC0=P1; | ||
73 | .Lquad_loop: MNOP || [P0++] = R1 || R1 = [I0++]; | ||
74 | [P0++] = R1; | ||
75 | |||
76 | CC = P2 == 0; /* any remaining bytes? */ | ||
77 | P3 = I0; /* Ammend P3 to updated ptr. */ | ||
78 | IF !CC JUMP .Lbytes; | ||
79 | P3 = I1; | ||
80 | RTS; | ||
81 | |||
82 | .Lbytes: LSETUP (.Lbyte2_s, .Lbyte2_e) LC0=P2; | ||
83 | .Lbyte2_s: R1 = B[P3++](Z); | ||
84 | .Lbyte2_e: B[P0++] = R1; | ||
85 | |||
86 | .Lfinished: P3 = I1; | ||
87 | RTS; | ||
88 | |||
89 | .Loverlap: | ||
90 | P2 += -1; | ||
91 | P0 = P0 + P2; | ||
92 | P3 = P3 + P2; | ||
93 | R1 = B[P3--] (Z); | ||
94 | CC = P2 == 0; | ||
95 | IF CC JUMP .Lno_loop; | ||
96 | LSETUP (.Lol_s, .Lol_e) LC0 = P2; | ||
97 | .Lol_s: B[P0--] = R1; | ||
98 | .Lol_e: R1 = B[P3--] (Z); | ||
99 | .Lno_loop: B[P0] = R1; | ||
100 | P3 = I1; | ||
101 | RTS; | ||
102 | |||
103 | .size _memmove,.-_memmove | ||