Listing 4 Loop unrolling: a) A simple loop; b) The same loop unrolled four times

a) for (i=0; i‹128; i++) { sum1 += const[i] * input[128 - i]; } b) for (i=0; i‹128; i++) { sum1 += const[i] * input[128 - i]; sum2 += const[2*i] * input[128 - (2*i)]; sum3 += const[3*i] * input[128 - (3*i)]; sum4 += const[4*i] * input[128 - (4*i)]; }

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