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[Bug middle-end/27986] [4.0/4.1/4.2 Regression] jump to middle of loop on entry with using old version of an variable



------- Comment #7 from amacleod at redhat dot com  2006-10-02 22:13 -------
Its not that you are expecting too much, just in the wrong place from my point
of view :-)  Changing the out of ssa algorithm or implementation isnt going to
change this code. It requires changing the code out of ssa sees.  

insert_backedge_copies() ought to be its own pass as well, as far as Im
concerned. Its the very first thing called, and is not related to the rest of
what out of ssa does at all.  

It should be moved out, and we can have an optimization pass just before
out-of-ssa which looks for this kind of thing.  That can happen when I start
adding the pre-passes for register pressure work if no one does it earlier.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=27986


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