diff options
| author | Taru Karttunen <taruti@taruti.net> | 2011-03-30 15:46:40 +0300 |
|---|---|---|
| committer | Taru Karttunen <taruti@taruti.net> | 2011-03-30 15:46:40 +0300 |
| commit | e5888a1ffdae813d7575f5fb02275c6bb07e5199 (patch) | |
| tree | d8d51eac403f07814b9e936eed0c9a79195e2450 /sys/src/ape/lib/ap/386/memmove.s | |
Import sources from 2011-03-30 iso image
Diffstat (limited to 'sys/src/ape/lib/ap/386/memmove.s')
| -rwxr-xr-x | sys/src/ape/lib/ap/386/memmove.s | 57 |
1 files changed, 57 insertions, 0 deletions
diff --git a/sys/src/ape/lib/ap/386/memmove.s b/sys/src/ape/lib/ap/386/memmove.s new file mode 100755 index 000000000..45a72225f --- /dev/null +++ b/sys/src/ape/lib/ap/386/memmove.s @@ -0,0 +1,57 @@ + TEXT memmove(SB), $0 + + MOVL p1+0(FP), DI + MOVL p2+4(FP), SI + MOVL n+8(FP), BX + CMPL BX, $0 + JGE ok + MOVL $0, SI +ok: + CLD +/* + * check and set for backwards + */ + CMPL SI, DI + JLS back +/* + * copy whole longs + */ + MOVL BX, CX + SHRL $2, CX + REP; MOVSL +/* + * copy the rest, by bytes + */ + ANDL $3, BX + MOVL BX, CX + REP; MOVSB + + MOVL p+0(FP),AX + RET +/* + * whole thing backwards has + * adjusted addresses + */ +back: + ADDL BX, DI + ADDL BX, SI + SUBL $4, DI + SUBL $4, SI + STD +/* + * copy whole longs + */ + MOVL BX, CX + SHRL $2, CX + ANDL $3, BX + REP; MOVSL +/* + * copy the rest, by bytes + */ + ADDL $3, DI + ADDL $3, SI + MOVL BX, CX + REP; MOVSB + + MOVL p+0(FP),AX + RET |