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Re: [dataflow]: PATCH COMMITTED


Kenneth Zadeck <zadeck@naturalbridge.com> writes:
> The actual change is what Iant told me to do after a long conversation
> with many people on irc.  Unfortunately this was several months ago when
> I was trying to get the ia-64 working and I have forgotten many of the
> details.  
>
> The fix is to deal with some hackery in the ia-64.  There is a failure
> that occurs when dce/dse is run after reload (which it never is on the
> mainline).

Are you sure?  I thought we ran PROP_KILL_DEAD_CODE passes after reload,
which is why we have things like REG_MAYBE_DEAD.

>  I believe, but I have forgotten all of the details, that an
> unspec is used rather than a use to keep something alive because a uses
> are not defined after reload and what we really wanted was a use.  There
> was a lot of chatting about this on irc as to whether to change this to
> an unspec volatile but in the end this is what ian told me to do. 
>
> The conversation was made on or right before sept 21.  Maybe danny can
> find the irc log.

Thanks, that'd be great.  It'd be a shame to have mysterious stuff
like this in the shiny new infrastructure ;)

Richard


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