re PR middle-end/67005 (ICE: in verify_loop_structure, at cfgloop.c:1647 (loop…

re PR middle-end/67005 (ICE: in verify_loop_structure, at cfgloop.c:1647 (loop with header n not in loop tree))

	PR middle-end/67005
	* tree-ssa-dce.c (remove_dead_stmt): Also schedule fixup if removing
	an entry into an irreducible region.

	* gcc.dg/torture/pr67005.c: New test.

From-SVN: r227268

gcc/ChangeLog

+2015-08-27  Marek Polacek  <polacek@redhat.com>
+
+	PR middle-end/67005
+	* tree-ssa-dce.c (remove_dead_stmt): Also schedule fixup if removing
+	an entry into an irreducible region.
+
 2015-08-27  Francois-Xavier Coudert  <fxcoudert@gcc.gnu.org>
 
 	* configure: Regenerate.

gcc/testsuite/ChangeLog

+2015-08-27  Marek Polacek  <polacek@redhat.com>
+
+	PR middle-end/67005
+	* gcc.dg/torture/pr67005.c: New test.
+
 2015-08-27  Alan Lawrence  <alan.lawrence@arm.com>
 
 	* gcc.dg/tree-ssa/sra-15.c: New.

gcc/testsuite/gcc.dg/torture/pr67005.c

+/* { dg-do compile } */
+
+int a;
+void
+f (void)
+{
+  if (!a);
+  else
+  lbl:
+    a = a;
+
+  if (a)
+    a = 8;
+  goto lbl;
+}

gcc/tree-ssa-dce.c

@@ -1125,10 +1125,11 @@ remove_dead_stmt (gimple_stmt_iterator *i, basic_block bb)
 	if (e != e2)
 	  {
 	    cfg_altered = true;
-	    /* If we made a BB unconditionally exit a loop then this
-	       transform alters the set of BBs in the loop.  Schedule
-	       a fixup.  */
-	    if (loop_exit_edge_p (bb->loop_father, e))
+	    /* If we made a BB unconditionally exit a loop or removed
+	       an entry into an irreducible region, then this transform
+	       alters the set of BBs in the loop.  Schedule a fixup.  */
+	    if (loop_exit_edge_p (bb->loop_father, e)
+		|| (e2->dest->flags & BB_IRREDUCIBLE_LOOP))
 	      loops_state_set (LOOPS_NEED_FIXUP);
 	    remove_edge (e2);
 	  }