Mart: A Mutant Generation Tool for LLVM

Program mutation makes small syntactic alterations to programs' code in order to artificially create faulty programs (mutants). Mutants are used, in software analysis, to evaluate and improve test suites. Mutants creation (generation) tools are often characterized by their mutation operators and the way they create and represent the mutants.

This paper presents Mart, a mutants generation tool, for LLVM bitcode, that supports the fine-grained definition of mutation operators (as matching rule - replacing pattern pair; uses 816 defined pairs by default) and the restriction of the code parts to mutate. New operators are implemented in Mart by implementing their matching rules and replacing patterns. Mart also implements in-memory Trivial Compiler Equivalence to eliminate equivalent and duplicate mutants during mutants generation. Mart generates mutant code as separated mutant files, meta-mutants file, weak mutation, and mutant coverage instrumented files. The generated LLVM bitcode files can be interpreted using an LLVM interpreter or compiled into native code. Mart is publicly available (https://github.com/thierry-tct/mart) for use by researchers and practitioners.

Mart has been applied to generate mutants for several research experiments and generated more than 4,000,000 mutants.