+//
+// This file implements methods that make it really easy to deal with intrinsic
+// functions with the isa/dyncast family of functions. In particular, this
+// allows you to do things like:
+//
+// if (DbgStopPointInst *SPI = dyn_cast<DbgStopPointInst>(Inst))
+// ... SPI->getFileName() ... SPI->getDirectory() ...
+//
+// All intrinsic function calls are instances of the call instruction, so these
+// are all subclasses of the CallInst class. Note that none of these classes
+// has state or virtual methods, which is an important part of this gross/neat
+// hack working.
+//
+// In some cases, arguments to intrinsics need to be generic and are defined as
+// type pointer to empty struct { }*. To access the real item of interest the
+// cast instruction needs to be stripped away.
+//
+//===----------------------------------------------------------------------===//