Enhanced fused multiply-add operation

An apparatus comprising:

• an exponent unit including:
• a first adder to generate S1, where S1 is the sum of at least the exponent of a floating point value A and the exponent of a floating point value B;
• a comparator to generate E1, where E1 is the greater of S1 and the exponent of a floating point value C;
• a multiplexer to set C to a constant in response to a control signal;
• a partial multiplier to generate partial products of the mantissas of A and B;
• a shifter to align the partial products and the mantissa of C, based on E1;
• and
• a second adder to generate S2, where S2 is the sum of the aligned partial products and the mantissa of C.

A method comprising:

• adding an integer k, the exponent of a floating point value A, and the exponent of a floating point value B to generate S1;
• comparing S1 to the exponent of a floating point value C to generate E1, where E1 is the greater of S1 and the exponent of C;
• multiplying the mantissa of A and B to generate partial products;
• shifting the partial products to align them with the mantissa of C, based on E1;
• and
• adding the aligned partial products and the mantissa of C.

A method comprising:

• adding at least the exponent of a floating point value A and the exponent of a floating point value B to generate S1;
• setting a floating point value C to a constant in response to a control signal;
• comparing S1 to the exponent of C to generate E1, where E1 is the greater of S1 and the exponent of a floating point value C;
• multiplying the mantissa of A and B to generate partial products;
• shifting the partial products to align them with the mantissa of C, based on E1;
• and
• adding the aligned partial products and the mantissa of C to generate S2.

A system comprising:

• a dynamic random access memory;
• and
• a processor coupled to the memory, having:
• an exponent unit including:
• a first adder to generate S1, where S1 is the sum of an integer k, the exponent of a floating point value A, and the exponent of a floating point value B;
• a comparator to generate E1, where E1 is the greater of S1 and the exponent of a floating point value C;
• a partial multiplier to generate partial products of the mantissas of A and B;
• a shifter to align the partial products and the mantissa of C, based on E1;
• and
• a second adder to add the aligned partial products and the mantissa of C.

A system comprising:

• a dynamic random access memory;
• and
• a processor coupled to the memory, having:
• an exponent unit including:
• a first adder to generate S1, where S1 is the sum of at least the exponent of a floating point value A, and the exponent of a floating point value B;
• a comparator to generate E1, where E1 is the greater of S1 and the exponent of a floating point value C;
• a multiplexer to set C to a constant in response to a control signal;
• a partial multiplier to generate partial products of the mantissas of A and B;
• a shifter to align the partial products and the mantissa of C, based on E1;
• and
• a second adder to generate S2, where S2 is the sum of the aligned partial products and the mantissa of C.