]>
Commit | Line | Data |
---|---|---|
a334319f UD |
1 | /* Copyright (C) 2002, 2003 Free Software Foundation, Inc. |
2 | This file is part of the GNU C Library. | |
3 | Contributed by Hartvig Ekner <hartvige@mips.com>, 2002. | |
4 | Ported to mips3 n32/n64 by Alexandre Oliva <aoliva@redhat.com> | |
5 | ||
6 | The GNU C Library is free software; you can redistribute it and/or | |
7 | modify it under the terms of the GNU Lesser General Public | |
8 | License as published by the Free Software Foundation; either | |
9 | version 2.1 of the License, or (at your option) any later version. | |
10 | ||
11 | The GNU C Library is distributed in the hope that it will be useful, | |
12 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
13 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
14 | Lesser General Public License for more details. | |
15 | ||
16 | You should have received a copy of the GNU Lesser General Public | |
17 | License along with the GNU C Library; if not, write to the Free | |
18 | Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA | |
19 | 02111-1307 USA. */ | |
20 | ||
21 | #include <sysdep.h> | |
22 | #include <endian.h> | |
23 | #include <sys/asm.h> | |
24 | ||
25 | ||
26 | /* void *memset(void *s, int c, size_t n); | |
27 | ||
28 | This could probably be optimized further. */ | |
29 | ||
30 | #if __BYTE_ORDER == __BIG_ENDIAN | |
31 | # define SDHI sdl /* high part is left in big-endian */ | |
32 | #else | |
33 | # define SDHI sdr /* high part is right in little-endian */ | |
34 | #endif | |
35 | ||
36 | ENTRY (memset) | |
37 | .set noreorder | |
38 | ||
39 | slti ta1, a2, 16 # Less than 16? | |
40 | bne ta1, zero, L(last16) | |
41 | move v0, a0 # Setup exit value before too late | |
42 | ||
43 | beq a1, zero, L(ueven) # If zero pattern, no need to extend | |
44 | andi a1, 0xff # Avoid problems with bogus arguments | |
45 | dsll ta0, a1, 8 | |
46 | or a1, ta0 | |
47 | dsll ta0, a1, 16 | |
48 | or a1, ta0 # a1 is now pattern in full word | |
49 | dsll ta0, a1, 32 | |
50 | or a1, ta0 # a1 is now pattern in double word | |
51 | ||
52 | L(ueven): | |
53 | PTR_SUBU ta0, zero, a0 # Unaligned address? | |
54 | andi ta0, 0x7 | |
55 | beq ta0, zero, L(chkw) | |
56 | PTR_SUBU a2, ta0 | |
57 | SDHI a1, 0(a0) # Yes, handle first unaligned part | |
58 | PTR_ADDU a0, ta0 # Now both a0 and a2 are updated | |
59 | ||
60 | L(chkw): | |
61 | andi ta0, a2, 0xf # Enough left for one loop iteration? | |
62 | beq ta0, a2, L(chkl) | |
63 | PTR_SUBU a3, a2, ta0 | |
64 | PTR_ADDU a3, a0 # a3 is last loop address +1 | |
65 | move a2, ta0 # a2 is now # of bytes left after loop | |
66 | L(loopw): | |
67 | PTR_ADDIU a0, 16 # Handle 2 dwords pr. iteration | |
68 | sd a1, -16(a0) | |
69 | bne a0, a3, L(loopw) | |
70 | sd a1, -8(a0) | |
71 | ||
72 | L(chkl): | |
73 | andi ta0, a2, 0x8 # Check if there is at least a double | |
74 | beq ta0, zero, L(last16) # word remaining after the loop | |
75 | PTR_SUBU a2, ta0 | |
76 | sd a1, 0(a0) # Yes... | |
77 | PTR_ADDIU a0, 8 | |
78 | ||
79 | L(last16): | |
80 | blez a2, L(exit) # Handle last 16 bytes (if cnt>0) | |
81 | PTR_ADDU a3, a2, a0 # a3 is last address +1 | |
82 | L(lst16l): | |
83 | PTR_ADDIU a0, 1 | |
84 | bne a0, a3, L(lst16l) | |
85 | sb a1, -1(a0) | |
86 | L(exit): | |
87 | j ra # Bye, bye | |
88 | nop | |
89 | ||
90 | .set reorder | |
91 | END (memset) | |
92 | libc_hidden_builtin_def (memset) |