ref: c8e940a59ea021afd6476593bff5194ad6f9eb13
dir: /sys/src/libc/mips/vlop.s/
TEXT _mulv(SB), $0 MOVW 8(FP), R2 MOVW 4(FP), R3 MOVW 16(FP), R4 MOVW 12(FP), R5 MULU R4, R2 MOVW LO, R6 MOVW HI, R7 MULU R3, R4 MOVW LO, R8 ADDU R8, R7 MULU R2, R5 MOVW LO, R8 ADDU R8, R7 MOVW R6, 4(R1) MOVW R7, 0(R1) RET