PARALLEL REDUNDANT DECIMAL FUSED-MULTIPLY-ADD CIRCUIT

摘要

A circuit for performing a floating-point fused-multiply-add (FMA) calculation of a×b±c. The circuit includes (i) a partial product generation module having (a) a multiples generator unit configured to generate multiples of a multiplicand has m digit binary coded decimal (BCD) format, (b) a recoding unit configured to generate n+1 signed digits (SD) sets from a sum vector and a carry vector of a multiplier, and (c) a multiples selection unit configured to generate partial product vectors from the multiples of the multiplicand based on the n+1 SD sets and the sign of FMA calculation, and (ii) a carry save adder (CSA) tree configured to add the partial product vectors and an addend to generate a result sum vector and a result carry vector in a m+n digit BCD format.