Intel Corporation
Apparatus and method for vector multiply and accumulate of packed words

Abstract:

An apparatus and method for performing multiply-accumulate operations. For example, one embodiment of a processor comprises: a decoder to decode instructions; a first source register to store a first plurality of packed words; a second source register to store a second plurality of packed words; a third source register to store a plurality of packed quadwords; execution circuitry to execute a first instruction, the execution circuitry comprising: extension circuitry to sign-extend or zero-extend the first and second plurality of packed words to generate a first and second plurality of doublewords corresponding to the first and second plurality of packed words; multiplier circuitry to multiply each of the first plurality of doublewords with a corresponding one of the second plurality of doublewords to generate a plurality of temporary products; adder circuitry to add at least a first set of the temporary products to generate a first temporary sum; accumulation circuitry to combine the first temporary sum with a first packed quadword value from a first quadword location in the third source register to generate a first accumulated quadword result; a destination register to store the first accumulated quadword result in the first quadword location.