predefined pass for transforming a module to SSA?

Hi all:

I’m writing a research prototype on LLVM 1.9.

Given a module ,what is the right way to get the SSA-based llvm-IR?
As I know , llvmgcc generates SSA-based bytecode.
But if a module is constructed by hand, how can I transform it into a SSA-based llvm?

Thanks.

Ying