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TEXT strcpy(SB), $0
MOVW s2+4(FP),R2 /* R2 is from pointer */
MOVW R1, R3 /* R3 is to pointer */
/*
* align 'from' pointer
*/
l1:
AND $3, R2, R5
ADDU $1, R2
BEQ R5, l2
MOVB -1(R2), R5
ADDU $1, R3
MOVB R5, -1(R3)
BNE R5, l1
RET
/*
* test if 'to' is also alligned
*/
l2:
AND $3,R3, R5
BEQ R5, l4
/*
* copy 4 at a time, 'to' not aligned
*/
l3:
MOVW -1(R2), R4
ADD $4, R2
ADD $4, R3
SRL $24,R4, R5
MOVB R5, -4(R3)
BEQ R5, out
SRL $16,R4, R5
AND $0xff, R5
MOVB R5, -3(R3)
BEQ R5, out
SRL $8,R4, R5
AND $0xff, R5
MOVB R5, -2(R3)
BEQ R5, out
AND $0xff,R4, R5
MOVB R5, -1(R3)
BNE R5, l3
out:
RET
/*
* word at a time both aligned
*/
l4:
MOVW $0xff000000, R7
MOVW $0x00ff0000, R8
l5:
ADDU $4, R3
MOVW -1(R2), R4 /* fetch */
ADDU $4, R2
AND R7,R4, R5 /* is it byte 0 */
AND R8,R4, R6 /* is it byte 1 */
BEQ R5, b0
AND $0xff00,R4, R5 /* is it byte 2 */
BEQ R6, b1
AND $0xff,R4, R6 /* is it byte 3 */
BEQ R5, b2
MOVW R4, -4(R3) /* store */
BNE R6, l5
JMP out
b0:
MOVB $0, -4(R3)
JMP out
b1:
SRL $24, R4
MOVB R4, -4(R3)
MOVB $0, -3(R3)
JMP out
b2:
SRL $24,R4, R5
MOVB R5, -4(R3)
SRL $16, R4
MOVB R4, -3(R3)
MOVB $0, -2(R3)
JMP out
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