Enhancing Spatial Locality using Data Layout Optimizations
M. Kandemir, A. Choudhaary, J. Ramanujam, N. Shenoy and P. Banerjee
Abstract
This paper aims to improve locality of references by suitably choosing
array layouts. We use a new definition of spatial reuse vectors that
takes into account memory layout of arrays. This capability creates
two opportunities. First, it allows us to develop an array
restructuring framework based on a combination of hyperplane theory
and reuse vectors. Second, it allows us to observe the effect of different
array layout optimizations on spatial reuse vectors. Since the
iteration space based locality optimizations also change the spatial
reuse vectors, our approach allows us to compare the iteration-space
based and data-space based approaches in terms of their effects on
spatial reuse vectors. We illustrate the effectiveness of our
technique using two benchmark examples on two distributed
shared-memory machines, the Convex Exemplar and the SGI Origin.