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TEXT memset(SB), $0
MOVL R0, R6
MOVBU data+4(FP), R2
MOVL n+8(FP), R10
ADDL R10, R0, R8
CMPUGE $8, R10, R1 /* need at least 8 bytes */
BNE R1, _1loop
SLLQ $8, R2, R1 /* replicate the byte */
OR R1, R2
SLLQ $16, R2, R1
OR R1, R2
SLLQ $32, R2, R1
OR R1, R2
_align:
AND $(8-1), R6, R1
BEQ R1, _aligned
MOVB R2, (R6)
ADDL $1, R6, R6
JMP _align
_aligned:
SUBL $(64-1), R8, R9 /* end pointer minus slop */
_64loop:
CMPUGT R9, R6, R1
BEQ R1, _8tail
MOVQ R2, (R6)
MOVQ R2, 8(R6)
MOVQ R2, 16(R6)
MOVQ R2, 24(R6)
MOVQ R2, 32(R6)
MOVQ R2, 40(R6)
MOVQ R2, 48(R6)
MOVQ R2, 56(R6)
ADDL $64, R6, R6
JMP _64loop
_8tail:
SUBL $(8-1), R8, R9
_8loop:
CMPUGT R9, R6, R1
BEQ R1, _1loop
MOVQ R2, (R6)
ADDL $8, R6
JMP _8loop
_1loop:
CMPUGT R8, R6, R1
BEQ R1, _ret
MOVB R2, (R6)
ADDL $1, R6
JMP _1loop
_ret:
RET
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