1. A method for backing up data, the method comprising: identifying a first file and a second file, wherein the second file comprises a first common portion and a first updated portion with respect to the first file; identifying a third file, wherein the third file comprises a second common portion and a second updated portion with respect to the first file; translating the first file, the second file, and the third file to respective abstract object trees; performing a series of predetermined abstract operations on the abstract object trees in order to generate a target abstract object tree; translating the target abstract object tree to a target file, wherein the target file comprises the second common portion, the second updated portion, and the first updated portion.