ref: 7420dc6adab03f28020243d71a3372cda15cacbc
dir: /sys/src/9/alphapc/memset.s/
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