1. A method comprising: a computer detecting that a first plurality of software instructions is configured to perform a plurality of breadth-first searches to determine a particular result, wherein each breadth-first search originates at a respective source vertex of a plurality of source vertices of a graph, wherein each breadth-first search is encoded for independent execution; based on the detecting, the computer consolidating the plurality of breadth-first searches into a simultaneous multi-source breadth-first search by transforming the first plurality of software instructions into a second plurality of software instructions that is configured to perform the simultaneous multi-source breadth-first search to determine the particular result, wherein each source vertex of the plurality of source vertices is a source of the simultaneous multi-source breadth-first search; the computer executing, or sending or storing for execution, said second plurality of software instructions to perform said simultaneous multi-source breadth-first search.
8. The method of claim 1 wherein the first plurality of software instructions comprises statements of a domain specific language (DSL).