Vector operations for compressing selected vector elements

摘要

A processor, method, and medium for using vector operations to compress selected elements of a vector. An input vector is compared to a criteria vector, and then a subset of the plurality of elements of the input vector are selected based on the comparison. A permutation vector is generated based on the locations of the selected elements and then the permutation vector is used to permute the selected elements of the input vector to an output vector. The selected elements of the input vector are stored in contiguous locations in the leftmost elements of the output vector. Then, the output vector is stored to memory and a pointer to the memory location is incremented by the number of selected elements.

主权项

1. A method comprising:
fetching instructions and data from a memory; decoding the fetched instructions; and processing decoded vector instructions used to compress vectors in the fetched data by:
performing a comparison of each of a plurality of elements of a source vector to given criteria to generate a result vector, wherein the result vector comprises a separate result of the comparison for each of the plurality of elements;performing a compressed select operation on the result vector to generate a permutation vector, wherein the permutation vector identifies one or more elements of the plurality of elements meeting the given criteria and identifies a permuted position for each of the one or more elements;performing a first permutation operation using said permutation vector on the plurality of elements of the source vector to generate an intermediate vector; andselecting the one or more elements of the plurality of elements in the intermediate vector meeting the given criteria to store in an output vector, wherein the output vector comprises only said one or more elements.