1) DIContext is now able to return function name for a given instruction address (besides file/line info).
2) llvm-dwarfdump accepts flag --functions that prints the function name (if address is specified by --address flag).
3) test case that checks the basic functionality of llvm-dwarfdump added
llvm-svn: 159512
This is only one half of it, the part that caches address ranges from the DIEs when .debug_aranges is
not available will be ported soon.
llvm-svn: 139680