The following fixes PR77282, tested on x86_64-unknown-linux-gnu, applied
as obvious.
Richard.
2016-08-18 Richard Biener <rguent...@suse.de>
PR tree-optimization/77282
* tree-ssa-pre.c (eliminate_dom_walker::before_dom_children):
When doing auto-parallelizing also prevent use of PHIs that
carry dependences across loop backedges.
Index: gcc/tree-ssa-pre.c
===================================================================
--- gcc/tree-ssa-pre.c (revision 239564)
+++ gcc/tree-ssa-pre.c (working copy)
@@ -4270,7 +4270,7 @@ eliminate_dom_walker::before_dom_childre
if (sprime
&& TREE_CODE (sprime) == SSA_NAME
&& do_pre
- && flag_tree_loop_vectorize
+ && (flag_tree_loop_vectorize || flag_tree_parallelize_loops)
&& loop_outer (b->loop_father)
&& has_zero_uses (sprime)
&& bitmap_bit_p (inserted_exprs, SSA_NAME_VERSION (sprime))
