An apparatus having a first circuit, a second circuit and a third circuit is disclosed. The first circuit may be configured to generate a plurality of load values corresponding to a trellis of a decoding process. The second circuit generally includes a plurality of calculation layers. The calculation layers may be configured to generate a plurality of maximum values in response to the load values. The third circuit may be configured to generate a plurality of L-values of the decoding process in response to the maximum values.