Patent ID: 6381624
Filing Date: 2002-04-30
Classification: G06F

Abstract:
A computer comprising a computer readable medium, said computer readable medium comprising instructions for of producing the accumulation of a product A*B of signed numbers A and B with a signed number C to produce A*B+C by:(a) determining the signs of input numbers A, B and C; (b) subsequent to the step (a), construing the input numbers A, B and C as positive two's complement numbers; (c) forming a two's complement positive product A*B of the construed as positive numbers A and B; (d) performing a one's complement on the construed as positive number C if the accumulation is addition and either the determined signs for A and B are the same with the determined sign for C being negative or the determined signs for A and B are different with the determined sign for C being positive; (e) performing a one's complement on the construed as positive number C if the accumulation is subtraction and either the determined signs for A and B are the same with the determined signs for C being positive or the determined signs for A and B are different with the determined sign for C being negative; (f) subsequent to steps (d) and (e), calculating the fixed point sum of the positive product A*B and the conditionally complemented number C; (g) conditionally incrementing the fixed point sum by one if the construed as positive number C was one's complemented in one of steps (d) and (e), thereby completing a two's complement and negation of the input number C; (h) performing a two's complement on the result of step (g) if the determined signs for A and B are different.