I wish to know if there exists any plugin that translate these intermediate format into C sources. I intent to modify these intermediate formats and retranslate then into C source to anylise the trasnsformations.
For reading a C like representation you can use -fdump-tree-*. It might have the information that you need.
For dumping real C you can use LLVM, but you will be able to dump only pre-optimized Gimple or the result of using LLVM optimizations on top of that. Rafael