Opcodes doc (mask_shl, size, offset, shl, value) (mask_shl, 256, 0, 0, val) == val (mask_shl, 255, 0, 1) == 2 * val (mask_shl, 254, 0, 2) == 4 * val (mask_shl, 255, 1, -1) == val / 2 evererything is in bits