How to get information of CUDA helper functions

Hi everyone,
I am starting with CUDA programming to speed up my programs. Reading provided examples from SDK is very helpful. However, in each application, there are some helper functions being used without any comments or explanation of their purpose. Can anyone tell me where I can get full information of these helper functions (such as cutilBankChecker, shrQAStart, shrLog, …and so with ones in cutil_inline.h, shrQATest.h, shrUtils.h …).
Many thanks.