1. Apparatus for processing data comprising: processing circuitry configured to compute one or more result values as a function of a plurality of input values; a memory configured to store said plurality of input values; load circuitry configured to issue one or more memory access requests to said memory to retrieve said plurality of input values from said memory and to supply said plurality of input values to said processing circuitry; wherein said plurality of input values are retrieved in a variable order from said memory; and said processing circuitry is configured to determine whether said input values can be processed in a variable order to compute said one or more result values, and wherein: (i) when said plurality of input values can be processed in a variable order to compute said one or more result values, said processing circuitry performs processing upon said plurality of input values to compute said one or more result values in a variable order that is dependent upon said variable order in which said plurality of input values are retrieved from said memory; and (ii) when said plurality of input values cannot be processed in a variable order, said processing circuitry performs processing upon said plurality of input values to compute said one or more result values in a fixed order that is independent of said variable order in which said plurality of input values are retrieved from said memory.