Making changes in GCC for Nios II

Hi, fellows! Hope someone could help me.

I'm doing an academic work in which I have to make changes in GCC's sources files. I have already downloaded the Nios II GCC's sources from (altera. com/ support/ ip/ processors/ nios2/ ide/ ips-nios2-ide-tutorial. html).

Now, my issues are:

1) In what source file do I must make the changes so I can have new informations in gmon.out file (the ones I implement)?

2) How do I compile the right files (the ones I changed)? Where is the "make" I must use?

3) What do I have to do in a way that the Nios II IDE can use the changed GCC file to compile C application files? Copy the changed files to some folder (in this case, which one)? Or can I compile the sources and have the executable already in the right folder? Where (the folder) Nios II IDE picks the GCC it uses?

I'm using Quartus II v11.1 (with QSys and Nios II at the same version) with Linux Ubuntu 10.10.