Abstract base class providing functionality that will be useful
for most dataflow analysis implementations that model instructions
within basic blocks.
Determine (1) what exceptions can be thrown on exception edges,
(2) which catch blocks are reachable, and (3) which exception
edges carry only "implicit" runtime exceptions.
Class to handle Strings annotated with embedded mnemonics
Note: Since the human interface guidelines for Mac OS X say never
to use mnemonics, this class behaves as if no mnemonics are set
when run on Mac OS X.