dest[0] = dest[0] * source[0] dest[1] = dest[1] * source[1] dest[2] = dest[2] * source[2] dest[3] = dest[3] * source[3]
The mulps instruction multiplies the 4 source values (second operand) to the 4 values of the destination (an XMM register). The source can be an XMM register or a 32 bit memory location. There is also vmumul on CPUs with AVX instructions which allows using 3 XMM registers or 2 XMM registers and a memory location which can simplify coding and which multiplies 8 pairs of values if you use YMM registers.
mulps xmm0, xmm1 ; multiply 4 pairs of values of xmm1 & xmm0 ; leave the rest of ymm0 as is mulps xmm0, [x] ; multiply 4 pairs of values of x & xmm0 ; x is an array of floats ; leave the rest of ymm0 as is vmulps xmm3, xmm0, xmm15 ; multiply 4 pairs of values of xmm0 & xmm15 ; store results in xmm3 vmulps ymm3, ymm0, [x] ; multiply 8 pairs of values of ymm0 & x ; store results in ymm3 vmulps ymm3, ymm0, [rsi] ; multiply 8 pairs of values of ymm0 & [rsi] ; rsi contains the address of an array ; store results in ymm3