> >So the threaded path lives fully inside loop1: 6->8->9->3->4->6 propagating > >that phi_inserted is 0 after the first iteration of the loop. This looks > >like > >useful loop peeling oppurtunity which does not garble loop structure. So > >perhaps threading paths starting and passing loop latch (i.e. peeling) is > >sane? Perhaps all paths fully captured in the loop in question are? > Peeling like this has long been a point of contention -- it totally > mucks things up like vectorizing. > > The general issue that the threader knows nothing about the > characteristics of the loop -- thus peeling is at this point is > premature and just as likely to hinder performance as improve it. > > I'm never been happy with how this aspect of threading vs loop opts > turned out and we have open BZs related to this rats nest of issues.
Ok, then we perhaps just want to silence the testcase? Honza > > jeff >
