bothner at cygnus.com
Tue Apr 29 17:00:59 PDT 1997
> Now while I was doing this I came
> across one aspect of the verification which doesn't seem to be well
> documented in the JVM book. Here's the problem: What types should the
> local variables be given at the start of an exception handler?
It seems clear to me. See 4th sentence page 130 - an exception
handler is a valid successor to *any* instruction in the associated
> Should is be a merge of all possible locals from anywhere in the exception
> block? This seems rather heavy handed to me, but perhas there's an
Well, at least conceptually, that seems to be what is needed.
But I agree, that seems a bit expensive. Some simplifications seem
easy - not doing a merge for instructions that cannot throw
an exception. And you only need to do a merge when the types
of a local variable has changed. So on the whole, I don't think
it should be too bad.
Cygnus Solutions bothner at cygnus.com http://www.cygnus.com/~bothner
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