As a part of the Lissom project, a retargetable decompiler is being developed. Its main purpose is to decompile programs for a particular microprocessor architecture into a high-level programming language. In present, methods of dynamic code analysis are not used during decompilation. However, we can significantly improve the decompilation results by using these methods. Design of dynamic-analysis methods is the main task of this thesis. In this thesis, reverse engineering and Lissom decompiler are described. Furthermore, general dynamic analysis methods, such as instrumentation and emulation, are described. The information we can obtain by using dynamic analysis and its usage during decompilation is proposed