US Patent 11165615 Data shifting operation apparatus and method having multiple operation modes

The present disclosure provides a data shifting operation apparatus having multiple operation modes that includes a preprocessing circuit, a first and a second shifting circuits and a multiplexer. The preprocessing circuit stores an input data group, having a data amount equal to a desired data amount M, to an under-operation data group, having the data amount equal to a maximum usage data amount N, from a most significant bit, and receives a shift amount S to calculate a total shift amount. The first and the second shifting circuits respectively cyclically shift the under-operation data group for the shift amount and the total shift amount to generate a first and a second shifted data groups. The multiplexer selects S data from the most significant bit of the second shifted data group and (M−S) data from the (N−S)-th bit of the first shifted data group to output a final shifted data group.