Formula processor having cache means for storing and retrieving results of previously computed formulas based on identification and dependency information

A formula processor which computes a result for a formula received from a host and returns the computed result to said host, said formula describing one or more operands capable of taking on values and one or more operations to be performed on the values of said operands, comprising:

• a computation element which is capable of performing a predetermined set of supported operations on said operands received from said host and further capable of determining whether a given operation is one of said supported operations;
• prior to each operation described by said formula, said computational element determines whether said operation is one of said supported operations,
• if said operation is one of said supported operations, said computation element performs said operation on the operands described by said formula,
• if said operation is not one of said supported operations, said computation element communicates an indication to said host that said operation is not supported by said computation element;
• said formula processor is compatible with a coprocessor which is compatible with said host, said formula processor responsive to coprocessor commands used by said host to communicate with the coprocessor, and performs, and responds to said coprocessor commands, functions equivalent to those performed by said coprocessor in response to said coprocessor commands,
• said formula processor responsive to formula commands not used by the host to communicate with said coprocessor, and performs, in response to said formula commands, formula calculations,
• said formula processor further adapted to perform said formula calculations and coprocessor functions simultaneously;
• state storage for storing and operative state of said formula processor;
• said formula processor, after responding to a formula command and prior to responding to a coprocessor signal, saves state information in said state storage;
• and
• said formula processor, after responding to a coprocessor command and prior to responding to a formula command, resets the state thereof by reading state information from said state storage.

A computer program product for use with a computer system, the computer system having a host processor capable of transmitting formulas, the formulas describing one or more operands capable of taking on values and one or more operations to be performed on the values of said operands, the computer program product comprising a computer useable memory having embodied in the memory program code means capable of performing a predetermined set of supported operations on the operands received from the host and further capable of determining whether a given operation is one of said supported operations, the memory further comprising:

• program code means for determining whether an operation is one of said supported operations, prior to each operation described by the formula, and for performing said operation on the operands if said operation is one of the supported operations, and for communicating an indication to the host that said operation is not supported by the computer program code means if the operation is not one of the supported operations, and
• program code means for storing operand values and pointers, one or more of the operands described by the formula being stored upon receipt of the formula, and
• program code means for computing the results for a plurality of formulas in which at least one formula identifies and uses the results of another formula, and
• program code means for storing a result of a first formula after computation and, if a second formula uses the results of said first formula retrieving the result of the first formula such that said retrieved result is used in computing the result of said second formula.