re PR c/44024 (missed optimization)

2010-05-09  Richard Guenther  <rguenther@suse.de>

	PR middle-end/44024
	* fold-const.c (tree_single_nonzero_warnv_p): Properly
	handle &FUNCTION_DECL.

	* gcc.dg/pr44024.c: New testcase.

From-SVN: r159205

gcc/ChangeLog

+2010-05-09  Richard Guenther  <rguenther@suse.de>
+
+	PR middle-end/44024
+	* fold-const.c (tree_single_nonzero_warnv_p): Properly
+	handle &FUNCTION_DECL.
+
 2010-05-09  Joseph Myers  <joseph@codesourcery.com>
 
 	PR c/4784

gcc/fold-const.c

@@ -14917,7 +14917,9 @@ tree_single_nonzero_warnv_p (tree t, bool *strict_overflow_p)
 
     case ADDR_EXPR:
       {
-	tree base = get_base_address (TREE_OPERAND (t, 0));
+	tree base = TREE_OPERAND (t, 0);
+	if (!DECL_P (base))
+	  base = get_base_address (base);
 
 	if (!base)
 	  return false;
@@ -14927,7 +14929,9 @@ tree_single_nonzero_warnv_p (tree t, bool *strict_overflow_p)
 	   allocated on the stack.  */
 	if (DECL_P (base)
 	    && (flag_delete_null_pointer_checks
-		|| (TREE_CODE (base) == VAR_DECL && !TREE_STATIC (base))))
+		|| (DECL_CONTEXT (base)
+		    && TREE_CODE (DECL_CONTEXT (base)) == FUNCTION_DECL
+		    && auto_var_in_fn_p (base, DECL_CONTEXT (base)))))
 	  return !VAR_OR_FUNCTION_DECL_P (base) || !DECL_WEAK (base);
 
 	/* Constants are never weak.  */

gcc/testsuite/ChangeLog

+2010-05-09  Richard Guenther  <rguenther@suse.de>
+
+	PR middle-end/44024
+	* gcc.dg/pr44024.c: New testcase.
+
 2010-05-09  Joseph Myers  <joseph@codesourcery.com>
 
 	PR c/4784

gcc/testsuite/gcc.dg/pr44024.c

+/* { dg-do link } */
+/* { dg-options "-fdelete-null-pointer-checks -fdump-tree-original" } */
+
+void foo();
+
+int main()
+{
+  if (foo == (void *)0)
+    link_error ();
+  return 0;
+}
+
+/* { dg-final { scan-tree-dump-not "foo" "original" } } */
+/* { dg-final { cleanup-tree-dump "original" } } */