projects / deliverable / linux.git / blame
| Commit | Line | Data |
|---|---|---|
| 1da177e4 LT |
1 | /* memmove.S: Simple memmove implementation. |
| 2 | * | |
| 3 | * Copyright (C) 1997, 2004 David S. Miller (davem@redhat.com) | |
| 4 | * Copyright (C) 1996, 1997, 1998, 1999 Jakub Jelinek (jj@ultra.linux.cz) | |
| 5 | */ | |
| 6 | ||
| 8695c37d | 7 | #include <linux/linkage.h> |
| d3867f04 | 8 | #include <asm/export.h> |
| 8695c37d | 9 | |
| 1da177e4 | 10 | .text |
| 8695c37d | 11 | ENTRY(memmove) /* o0=dst o1=src o2=len */ |
| 2077cef4 DM |
12 | brz,pn %o2, 99f |
| 13 | mov %o0, %g1 | |
| 14 | ||
| 1da177e4 | 15 | cmp %o0, %o1 |
| 2077cef4 | 16 | bleu,pt %xcc, 2f |
| 1da177e4 LT |
17 | add %o1, %o2, %g7 |
| 18 | cmp %g7, %o0 | |
| 19 | bleu,pt %xcc, memcpy | |
| 20 | add %o0, %o2, %o5 | |
| 21 | sub %g7, 1, %o1 | |
| 22 | ||
| 23 | sub %o5, 1, %o0 | |
| 24 | 1: ldub [%o1], %g7 | |
| 25 | subcc %o2, 1, %o2 | |
| 26 | sub %o1, 1, %o1 | |
| 27 | stb %g7, [%o0] | |
| 28 | bne,pt %icc, 1b | |
| 29 | sub %o0, 1, %o0 | |
| 2077cef4 | 30 | 99: |
| 1da177e4 LT |
31 | retl |
| 32 | mov %g1, %o0 | |
| 2077cef4 DM |
33 | |
| 34 | /* We can't just call memcpy for these memmove cases. On some | |
| 35 | * chips the memcpy uses cache initializing stores and when dst | |
| 36 | * and src are close enough, those can clobber the source data | |
| 37 | * before we've loaded it in. | |
| 38 | */ | |
| 39 | 2: or %o0, %o1, %g7 | |
| 40 | or %o2, %g7, %g7 | |
| 41 | andcc %g7, 0x7, %g0 | |
| 42 | bne,pn %xcc, 4f | |
| 43 | nop | |
| 44 | ||
| 45 | 3: ldx [%o1], %g7 | |
| 46 | add %o1, 8, %o1 | |
| 47 | subcc %o2, 8, %o2 | |
| 48 | add %o0, 8, %o0 | |
| 49 | bne,pt %icc, 3b | |
| 50 | stx %g7, [%o0 - 0x8] | |
| 51 | ba,a,pt %xcc, 99b | |
| 52 | ||
| 53 | 4: ldub [%o1], %g7 | |
| 54 | add %o1, 1, %o1 | |
| 55 | subcc %o2, 1, %o2 | |
| 56 | add %o0, 1, %o0 | |
| 57 | bne,pt %icc, 4b | |
| 58 | stb %g7, [%o0 - 0x1] | |
| 59 | ba,a,pt %xcc, 99b | |
| 8695c37d | 60 | ENDPROC(memmove) |
| d3867f04 | 61 | EXPORT_SYMBOL(memmove) |