Babel? LLVM? Parser needed

Can someone point me to where I need to go, if indeed there is a product that can help ... We need be able to parse code from another compiler and extract objects from it. Another group is writing code in C, using the Greenhills C compiler (Multi). We will have their source code, as well as compiled products. We need to parse it and extract the pieces of interest to us. We will be interested in the objects of user-defined types, not "symbols" as in methods/functions, that we could get from a COFF or ELF parser. For example, they will declare typedef struct MySpecialType whose members made up of types of other user-defined types. We will need to do something like build arrays of all the typedefs so we can connect the dots ... when we see an object of type MySpecialType, we can traverse the array to get all the information about that object to know its makeup, break it down to the bit level. This will allow us to match patterns in data to these types so we can interpret the data.

We want to either use a .NET tool or develop a tool in .NET to do this.

I ran across references to "Babel" this morning and am wondering if it will give us the ability to do this. Also I've seen references to LLVM.

Thank you for your help.