DATA PROCESSING APPARATUS AND METHOD FOR PERFORMING A SHIFT FUNCTION ON A BINARY NUMBER

摘要

A data processing apparatus and method are provided for performing a shift function on a binary number. The apparatus comprises count determination circuitry for determining a number of contiguous bit positions in the binary number that have a predetermined bit value, the count determination circuitry outputting a count value indicative of the number of contiguous bit positions determined. In parallel with the operation of the count determination circuitry, coarse shifting circuitry is used to determine, for at least one predetermined number of contiguous bit positions, whether that predetermined number of contiguous bit positions within the binary number has said predetermined bit value. An initial shift operation is then performed on the binary number based on that determination in order to produce an intermediate binary number. Once the count value is available from the count determination circuitry, fine shifting circuitry then performs a further shift operation on the intermediate binary number, based on the count value output by the count determination circuitry, in order to produce the result binary number. This provides an efficient mechanism for performing a shift function on a binary number, whilst still capturing the count value from the count determination circuitry.

主权项

1. A data processing apparatus for performing a shift function on a binary number, comprising:
count determination circuitry configured to determine a number of contiguous bit positions in the binary number having a predetermined bit value, and to output a count value indicative of said number of contiguous bit positions; coarse shifting circuitry configured to determine, for at least one predetermined number of contiguous bit positions, whether said predetermined number of contiguous bit positions within the binary number has said predetermined bit value, and to perform an initial shift operation on the binary number based on said determination in order to produce an intermediate binary number, said coarse shifting circuitry operating in parallel with said count determination circuitry; and fine shifting circuitry configured to perform a further shift operation on the intermediate binary number, based on the count value output by the count determination circuitry, in order to produce a result binary number.