parallel_case and full_case
case (state) 0: next = 1; 1: next = 2;
2: next = 0; default: next = 'bxx; endcase
case (1’b1) // synopsys parallel_case s[0]: out = a; s[1]: out = b; s[2]: out = c; s[3]: out = d; endcase
case (state) // synopsys full_case 0: next = 1; 1: next = 2; 2: next = 0; endcase
out = s[0]•a + s[1]•b + s[2]•c + s[3]•d;