[patch] Clear all EDGE_LOOP_EXIT flags in mark_loop_exit_edges

Jeffrey A Law law@redhat.com
Wed Mar 30 17:54:00 GMT 2005


On Tue, 2005-03-29 at 09:29 +0200, Zdenek Dvorak wrote:
> Hello,
> 
> as an optimization, mark_loop_exit_edges skips blocks that are outside
> any loops, since there may be no loop exits from them.  However, this
> means that if an edge is marked EDGE_LOOP_EXIT and then the loop is
> removed (or just the edge is split and the edge ceases to be the loop
> exit), the edge is marked EDGE_LOOP_EXIT forever.  This may block
> if_convert from working with such an edge.
> 
> I have noted this when working on disabling the old loop optimizer;
> the problem is masked otherwise, since the old loop removes the
> cfg and "clears" all flags as a side effect.
> 
> Bootstrapped & regtested on i686.
> 
> Zdenek
> 
> 	* cfgloopanal.c (mark_loop_exit_edges): Clean EDGE_LOOP_EXIT
> 	flag for edges outside any loops.
Approved.  Please install if you haven't already done so.

Thanks,
Jeff




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