[REPOST] MT-safe exception diffs for 971207

[Teemu Torma]

    From:  Jason Merrill <jason@cygnus.com>
    Date:  11 Dec 1997 19:36:28 -0800

    In use_eh_context, why are you using copy_rtx on a REG rtx?  That's a nop.

I have noticed that there are obsolete moves which are left over while I
have changed the code.  I haven't bothered yet to optimize them out.

     I'm not sure why you need five functions to handle eh_context.

Convenience, fewer changes to the other code to help merging.  No need to
do it that way.

    Why do you cast &eh->info and &eh->dynamic_handler_chain to their own
    types?

If I understand you correctly, __get_dynamic_handler_chain is not needed
anymore, so it can be taken away.  __get_eh_info is there so that the
compiler does not need to know that much of the contents of eh_context.

Teemu