Modified patch by Adam Preuss.
This builds on the existing framework for block tracing, edge profiling and optimal edge profiling.
See -help-hidden for new flags.
For documentation, see the technical report "Implementation of Path Profiling..." in llvm.org/pubs.
llvm-svn: 124515
premature, these libraries will be going away for the 2.0 release. Other
arrangements for profiling, gc, etc. should be made in the next few months.
llvm-svn: 31807