Use the library LPMs for functions such as multiply, adders and counters. Many arithmetic designs use multiply/accumulate algorithms. Multipliers are easily pipelined to increase speed but accumulators pose a more difficult control problem when pipelined. The accumulator usually runs slower than the pipelined multiply. If the compiler settings cannot produce a fast enough adder, we have some adder techniques that will increase the speed by 2-4 times depending upon the number of bits. Since multiply hardware is just a lot of adders, this same architecture can be used to increase multiply pipeline speed. If more multiply speed is required, there are some "number base conversion" schemes to further increase speed and reduce hardware.
Counters use the same carry logic as adders and the same compiler settings used for adders can help here. For long counters, similar techniques to the fast adder can be employed to increase speed.
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