| 摘要 |
A multiply execution unit that is operable to generate the integer product and the XOR product of a multiplicand and a multiplier. The multiply execution unit includes a summing circuit for summing a plurality of partial products. The partial products may be Booth encoded. The summing circuit can generate an integer sum of the plurality of partial products and can generate an XOR sum of the plurality of partial products. The summing circuit includes a first plurality of full adders. The first plurality of full adders each has three inputs, a carry output, and a sum output. The sum outputs of the first plurality of full adders are independent of the value of any carry output in the summing circuit. The summing circuit also includes a second plurality of full adders. The second plurality of full adders each has three inputs, a carry output, and a sum output. The XOR sum is dependent upon at least one of the sum outputs of the first plurality of full adders but is independent of the sum outputs of the second plurality of full adders. The integer sum is dependent upon the sum outputs of at least one of the first plurality of full adders and is also dependent on at least one of the sum outputs of the second plurality of full adders.
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