@richard I just now realized that I can not use any of winograd/gemm/FTT algorithms to do XNOR conv2d or matrix multiplication or whatever. This algorithms introduce additional additions, so every time I do for example strassen 12 fast matrix multiplication nested item I come out from {-1, 1} diapason and to bigger one {-2, 0, 2} and so on.

Starssen2.png671×854 54.7 KB

Same stuff for winograd and FFT. So anybody could only use naive student like realization XNOR Conv2d without any karatsuba speedup