1. A method for creating a library method stub in source code form corresponding to an original library call in machine-executable form, said method comprising: creating, by a computer processor, the library method stub in a predefined programming language by use of a library method signature associated with the original library call, at least one idiom sentence, and a call invoking the original library call, wherein said creating the library method stub comprises composing source code of the library method stub by matching the at least one idiom sentence with idiom-stub mappings predefined for each basic idiom of at least one basic idiom, wherein the original library call appears in sequential code, wherein the library method signature specifies formal arguments of the original library call, wherein the at least one idiom sentence summarizes memory operations performed by the original library call on the formal arguments, and wherein a sentence S of the at least one basic idiom provides at least one rule for generating a composition of literals to generate a complex idiom; and said processor storing the created library method stub in a database.