Data flow diagram generation from c source

This may be an elementary question and if so please understand that I am a newbie to fpgas. I am looking for software that can generrate

a dataflow diagram from c code. Please undertstand that I am not requesting a drawing program-that is easy to find.

I am trying to find some software that can generate a DFD from the actual c source.

I know that IBM makes one, but it costs several thousand dollars. That will not work for me.

I know that the software package Trimararn can do this, but it is quite diificult to install.

Any suggestion appprciated.

Thanks in advance.

Respectfuly,

Lou Reed