re PR tree-optimization/69196 (code size regression with jump threading at -O2)

	PR tree-optimization/69196
	* tree-ssa-threadbackward.c (fsm_find_control_statement_thread_paths):
	If the both SSA_NAMEs are anonymous, then consider them unassociated
	and include the PHI in the statement count.

From-SVN: r233999

gcc/ChangeLog

+2016-03-04  Jeff Law  <law@redhat.com>
+
+	PR tree-optimization/69196
+	* tree-ssa-threadbackward.c (fsm_find_control_statement_thread_paths):
+	If the both SSA_NAMEs are anonymous, then consider them unassociated
+	and include the PHI in the statement count.
+
 2016-03-05  Tom de Vries  <tom@codesourcery.com>
 
 	* omp-low.c (check_omp_nesting_restrictions): Check for non-oacc

gcc/tree-ssa-threadbackward.c

@@ -311,7 +311,11 @@ fsm_find_control_statement_thread_paths (tree name,
 			  gphi *phi = gsip.phi ();
 			  tree dst = gimple_phi_result (phi);
 
-			  if (SSA_NAME_VAR (dst) != SSA_NAME_VAR (name)
+			  /* Note that if both NAME and DST are anonymous
+			     SSA_NAMEs, then we do not have enough information
+			     to consider them associated.  */
+			  if ((SSA_NAME_VAR (dst) != SSA_NAME_VAR (name)
+			       || !SSA_NAME_VAR (dst))
 			      && !virtual_operand_p (dst))
 			    ++n_insns;
 			}