Fast memory footprint estimation based on maximal dependency vector calculation

In data dominated applications, loop transformations have a huge impact on the lifetime of array data and therefore on memory footprint. Since a locally optimal loop transformation may have a detrimental effect somewhere else, many alternative loop transformations need to be explored. Therefore, estimation of the memory footprint is essential, and this estimation has to be fast. This paper presents a fast array based memory footprint estimation technique based on counting of iteration nodes in an iteration domain constrained by a maximal lifetime. The maximal lifetime is defined by the Maximal Dependency Vector (MDV) of the array for a given execution ordering. We further present for the first time two approaches for calculation of the MDV: a general approach based on an ILP formulation and a novel vertexes approach when iteration domains are approximated by bounding boxes. Experiments on practical test vehicles demonstrate that the estimation based on our vertexes approach is extre...

• Type: Conference
• Year: 2007
• Where: DATE
• Authors: Qubo Hu, Arnout Vandecappelle, Per Gunnar Kjeldsberg, Francky Catthoor, Martin Palkovic
• Keywords: DATE 2007, Hardware, Loop Transformations, Maximal Lifetime, Memory Footprint