R0(x0, x1), R1(x0, x1)
R2(x1, x2), R3(x0, x2), R4(x1, x2), R5(x1, x2), R6(x0, x2)
R7(x2, x3), R8(x0, x3), R9(x2, x3), R10(x1, x3), R11(x0, x3), R12(x2, x3), R13(x1, x3), R14(x2, x3), R15(x1, x3)
