10. The system of claim 9 in which said selected code block comprises a plurality of elemental vector instructions designating particular operations to perform using elements of a plurality of arrays, wherein said means for generating subgrid loop creation instructions comprises: means for determining an array size of arrays which are processed by said processing element during execution in said processing element of low-level vector instructions corresponding to said elemental vector instructions in said selected code block; means for calculating said value, X, of said iteration counter as a function of said array size and as a function of predetermined indicia indicating the number of array elements processed by said processing element during each iteration of said subgrid loop; and means for generating said subgrid loop creation instructions such that said processing element processes the elements of the arrays distributed to said processing element over X iterations of said subgrid loop.
11. The system of claim 10, wherein said predetermined indicia indicates that four array elements are processed by said processing element during each iteration of said subgrid loop.