[Bug bootstrap/48000] [4.6 Regression] LTO bootstrap failed with bootstrap-profiled

[jakub at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=48000

Jakub Jelinek <jakub at gcc dot gnu.org> changed:

           What    |Removed                     |Added
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                 CC|                            |jakub at gcc dot gnu.org

--- Comment #5 from Jakub Jelinek <jakub at gcc dot gnu.org> 2011-03-06 17:38:11 UTC ---
(In reply to comment #4)
> Created attachment 23559 [details]
> A proposed patch
> 
> This fixes the problem uncovered by the previous fix.  In fix_bb_placements, we
> restrict the placement changes to the basic blocks that originally were in the
> base loop (the loop containing the FROM basic block).  This is achieved by
> marking the header of the loop visited, so that we never enter it to the
> processing queue.  However, if FROM itself is the header of the loop, this
> fails, as we enter FROM to the queue unconditionally.  Fixed by ending
> immediatelly if FROM is a loop header.

Successfully bootstrapped/regtested on x86_64-linux and i686-linux as well as
successfully profiledbootstrapped/regtested on those two targets (the latter is
what was failing before), no regressions.