Function LLVMFinalizeFunctionPassManager 

pub unsafe extern "C" fn LLVMFinalizeFunctionPassManager(
    FPM: LLVMPassManagerRef,
) -> LLVMBool

Finalizes all of the function passes scheduled in the function pass manager. Returns 1 if any of the passes modified the module, 0 otherwise. @see llvm::FunctionPassManager::doFinalization