2017-06-26 Richard Biener <rguenther@suse.de>

2017-06-26  Richard Biener  <rguenther@suse.de>

        PR tree-optimization/80928
	* cfghooks.c (duplicate_block): Do not copy BB_DUPLICATED flag.
	(copy_bbs): Set BB_DUPLICATED flag early.
	(execute_on_growing_pred): Do not execute for BB_DUPLICATED
	marked blocks.
	(execute_on_shrinking_pred): Likewise.
	* tree-ssa.c (ssa_redirect_edge): Do not look for PHI args in
	BB_DUPLICATED blocks.
	* tree-ssa-phionlycoprop.c (eliminate_degenerate_phis_1): Properly
	iterate over all PHIs considering removal of *gsi.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@249638 138bc75d-0d04-0410-961f-82ee72b054a4