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TEXT strcpy(SB), $-4
MOVW R0, to+0(FP) /* need to save for return value */
MOVW from+4(FP), R1
MOVW $0xFF, R2 /* mask */
salign: /* align source on 4 */
AND.S $3, R1, R3
BEQ dalign
MOVBU.P 1(R1), R3 /* implicit write back */
TST R3, R2
MOVBU.P R3, 1(R0) /* implicit write back */
BNE salign
B return
dalign: /* is destination now aligned? */
AND.S $3, R0, R3
BNE uloop
aloop:
MOVW.P 4(R1), R4 /* read 4, write 4 */
TST R4, R2 /* AND.S R3, R2, Rx */
TST.NE R4>>8, R2
TST.NE R4>>16, R2
TST.NE R4>>24, R2
BEQ tail
MOVW.P R4, 4(R0)
B aloop
uloop:
MOVW.P 4(R1), R4 /* read 4, write 1,1,1,1 */
tail:
AND.S R4, R2, R3
MOVBU.NE.P R3, 1(R0)
AND.NE.S R4>>8, R2, R3
MOVBU.NE.P R3, 1(R0)
AND.NE.S R4>>16, R2, R3
MOVBU.NE.P R3, 1(R0)
AND.NE.S R4>>24, R2, R3
MOVBU.P R3, 1(R0)
BNE uloop
B return
return:
MOVW to+0(FP), R0
RET
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