[LLVMdev] Loading ProfileInfo

[Eric Zimmerman]

Hi LLVMers,

I am fairly new to the LLVM pass framework.  My goal is to extend the
CFGPrinter analysis pass to label the edges of the graph with their
edge-counts from profile data.

I can generate the CFGs using 'analyze', but I am having trouble
loading the profile data.  I added the line
AU.addRequired<ProfileInfo>(); to the getAnalysisUsage.  It is
returning zero for all the edge counts.

In llvm/Analysis/ProfileInfo.h, I noticed a prototype: 
Pass *createProfileLoaderPass(const std::string &Filename);  

The ProfileInfoLoaderPass does not appear in the list of analyses,
presumably because it is registered as an "Opt".  Do I need to
explicitly request a LoaderPass in addition to ProfileInfo?  What is
the right way to do this?

Thanks.