documentation on "sjlj exceptions", DWARF2, etc?

Sun Dec 16 13:53:00 GMT 2001

Jeff Sturm <jsturm@one-point.com> writes:
> The advantages of sjlj EH is a simpler, more portable
> implementation, and smaller size. The primary disadvantage is
> performance: it incurs some cost even if no exception is never
> thrown.

How bad is the performance hit? Is it one instruction (saving a jump
address), or is there some register-saving involved even if an
exception never gets thrown?
 - a