re PR tree-optimization/47141 (segfault)

* PR tree-optimization/47141
	* ipa-split.c (split_function): Handle case where we are returning a
	value and the return block has a virtual operand phi.

	* gcc.c-torture/compile/pr47141.c: New test.

Approved by richie in IRC

From-SVN: r168634

gcc/ChangeLog

@@ -1,3 +1,9 @@
+2011-01-10  Jeff Law  <law@redhat.com>
+
+	* PR tree-optimization/47141
+	* ipa-split.c (split_function): Handle case where we are
+	returning a value and the return block has a virtual operand phi.
+
 2011-01-10  Jan Hubicka  <jh@suse.cz>
 
 	PR tree-optimization/47234 

gcc/ipa-split.c

@@ -1016,20 +1016,31 @@ split_function (struct split_point *split_point)
       e->probability = REG_BR_PROB_BASE;
       e->count = new_return_bb->count;
       bitmap_set_bit (split_point->split_bbs, new_return_bb->index);
-      /* We change CFG in a way tree-inline is not able to compensate on while
-	 updating PHIs.  There are only virtuals in return_bb, so recompute
-	 them.  */
+    }
+  /* When we pass around the value, use existing return block.  */
+  else
+    bitmap_set_bit (split_point->split_bbs, return_bb->index);
+
+  /* If RETURN_BB has virtual operand PHIs, they must be removed and the
+     virtual operand marked for renaming as we change the CFG in a way that
+     tree-inline is not able to compensate for. 
+
+     Note this can happen whether or not we have a return value.  If we have
+     a return value, then RETURN_BB may have PHIs for real operands too.  */
+  if (return_bb != EXIT_BLOCK_PTR)
+    {
       for (gsi = gsi_start_phis (return_bb); !gsi_end_p (gsi);)
 	{
 	  gimple stmt = gsi_stmt (gsi);
-	  gcc_assert (!is_gimple_reg (gimple_phi_result (stmt)));
+	  if (is_gimple_reg (gimple_phi_result (stmt)))
+	    {
+	      gsi_next (&gsi);
+	      continue;
+	    }
 	  mark_virtual_phi_result_for_renaming (stmt);
 	  remove_phi_node (&gsi, true);
 	}
     }
-  /* When we pass aorund the value, use existing return block.  */
-  else
-    bitmap_set_bit (split_point->split_bbs, return_bb->index);
 
   /* Now create the actual clone.  */
   rebuild_cgraph_edges ();

gcc/testsuite/ChangeLog

@@ -1,3 +1,8 @@
+2011-01-10  Jeff Law <law@redhat.com>
+
+	* PR tree-optimization/47141
+	* gcc.c-torture/compile/pr47141.c: New test.
+
 2011-01-10  Eric Botcazou  <ebotcazou@adacore.com>
 
 	PR testsuite/46230

gcc/testsuite/gcc.c-torture/compile/pr47141.c

@@ -0,0 +1,16 @@
+int
+foo (__UINTPTR_TYPE__ x)
+{
+  int a = 6;
+  int *b = &a;
+  if (x)
+    for (a = 0; a; a++)
+      ;
+  return a;
+}
+
+void
+bar (void)
+{
+  foo ((__UINTPTR_TYPE__) foo);
+}