US 9,811,503 B1
Methods for implementing arithmetic functions with user-defined input and output formats
Bogdan Pasca, Chesham (GB)
Assigned to Altera Corporation, San Jose, CA (US)
Filed by Altera Corporation, San Jose, CA (US)
Filed on Jan. 28, 2015, as Appl. No. 14/608,113.
Int. Cl. G06F 17/10 (2006.01); G06F 17/17 (2006.01)
CPC G06F 17/17 (2013.01) 19 Claims
OG exemplary drawing
 
1. Circuitry configured to implement a function, comprising:
a generic approximation circuit that generates output values for the function;
memory for storing a table of pre-computed output values for the function, wherein the function comprises a fixed-point arithmetic function having an input range, and wherein the pre-computed output values in the table correspond to input values within the input range for which the generic approximation circuit is incapable of generating sufficiently accurate output values; and
a multiplexing circuit that receives the output values from the generic approximation circuit, that receives the pre-computed output values in the table, and that is configured to route output values from a selected one of the generic approximation circuit and the table to a multiplexer output.