1. A computer-implemented method for increasing parallelization in a computer program, comprising: obtaining a binary associative operator and an ordered set of elements associated with a prefix operation in the computer program; dividing the elements into multiple sets of contiguous iterations based on a number of processors used to execute the computer program; calculating, in parallel on the processors, a set of local reductions from the contiguous iterations, wherein each local reduction in the set is calculated by applying the binary associative operator between all elements in a corresponding contiguous iteration from the set of the contiguous iterations; for each given local reduction in a subset of the local reductions, calculating a first boundary prefix for the given local reduction by using the given local reduction and a second boundary prefix for a second local reduction in a second subset that precedes the given local reduction, wherein the second boundary prefix is calculated from the second local reduction and a third boundary prefix for a third local reduction in a third subset that precedes the second subset; and obtaining a set of prefixes for the ordered set of elements by applying, in parallel on the processors, the boundary prefixes to the contiguous iterations using the binary associative operator.