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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
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