Slight refactoring of SGEMM ubench
Slight refactoring of SGEMM ubench

Maratyszcza/NNPACK,microblink/NNPACK,Maratyszcza/NNPACK,microblink/NNPACK,microblink/NNPACK,Maratyszcza/NNPACK,Maratyszcza/NNPACK,microblink/NNPACK