| 摘要 |
An arithmetic logic unit (ALU) with improved critical path performance includes two sets of adder circuits, a logic circuit, a set of multiplexors and a decoder. The adder circuits perform redundant add operations, one with a unit carry input and one without a carry input, upon multiple respective portions of the two sets of input signal bits. The logic circuit performs Boolean logic operations upon the two sets of input signal bits. In accordance with a set of selection control signals, the multiplexors select among the multiple results of such redundant add operations and Boolean logical operations for outputting as the final output bits. Such selection control signals are generated by the decoder based upon the contents of the two sets of input signal bits.
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