Describe the execution of a C++ code by generating pretty callgraph and write a report - Doing Reverse-Engineering

I have, on Linux, a working C++ code and I would like to understand it better. That's why I need an expert in C++ who will analyze this code and describes its execution. This is done by a pretty callgraph (I want to be able to generate it myself whatever the tool used for) and description of the code. Actually, I mainly want to do Reverse-Engineering. A numerical recipie for the code is already done but I want to understand how things have been coded. There are, in the XSAF_C_magma.cpp, 3 possibilies for the routine of matrix inversion : MAGMA routine called " matrix_inverse_magma", the second one with Intel LAPACKE called "matrix_inverse_lapack" and the last one classical "matrix_inverse". The fastest running is reached with MAGMA routine. The Archive of the project is on : http://31.207.36.11/Archive_Project_CUDA_MAGMA.tar.gz .Best regards.