1. A computer implemented method for shuffling packed data elements comprising: decoding a single instruction specifying a single field of per-lane control bits, and indicating a source operand and a destination operand, the source operand having a plurality of lanes and the destination operand having a plurality of corresponding lanes, each lane of the source and destination operands having an upper half including at least four data elements and a lower half including at least four data elements; responsive to decoding the single instruction and the single field of the per-lane control bits: selecting a plurality of sets of data elements, each of the plurality of sets of data elements corresponding to a different one of the plurality of lanes of the source operand, using the single field of the per-lane control bits for each of the plurality of lanes of the source operand, wherein each data element in each set of data elements is to be selected from any data elements in only the lower half of the corresponding lane of the source operand; and copying each set of data elements to the lower half of the corresponding lane of the destination operand.