re PR tree-optimization/35402 (Store CCP will not inline static const variable…

re PR tree-optimization/35402 (Store CCP will not inline static const variable which is default initialized)

2008-03-06  Andrew Pinski  <andrew_pinski@playstation.sony.com>

        PR tree-opt/35402
        * tree-ssa-ccp.c (get_symbol_constant_value): Handle
        integral and scalar float variables which have a
        NULL DECL_INITIAL.

2008-03-06  Andrew Pinski  <andrew_pinski@playstation.sony.com>

        PR tree-opt/35402
        * gcc.dg/tree-ssa/ssa-store-ccp-1.c: New test.

From-SVN: r132991

gcc/ChangeLog

+2008-03-06  Andrew Pinski  <andrew_pinski@playstation.sony.com>
+
+	PR tree-opt/35402
+	* tree-ssa-ccp.c (get_symbol_constant_value): Handle
+	integral and scalar float variables which have a
+	NULL DECL_INITIAL.
+
 2008-03-06  Nathan Froyd  <froydnj@codesourcery.com>
 
 	* dwarf2out.c (dwarf2out_frame_debug_expr): Consult the

gcc/testsuite/ChangeLog

+2008-03-06  Andrew Pinski  <andrew_pinski@playstation.sony.com>
+
+	PR tree-opt/35402
+	* gcc.dg/tree-ssa/ssa-store-ccp-1.c: New test.
+
 2008-03-06  Markus Milleder  <markus.milleder@generali.at>
 
 	PR preprocessor/35458

gcc/testsuite/gcc.dg/tree-ssa/ssa-store-ccp-1.c

+/* { dg-do compile } */
+/* { dg-options "-O2 -fdump-tree-optimized" } */
+
+static const int conststaticvariable;
+
+int f(void)
+{
+  return conststaticvariable;
+}
+
+/* There should be no reference to conststaticvariable as we should have
+   inlined the 0. */
+/* { dg-final { scan-tree-dump-times "conststaticvariable" 0 "optimized"} } */
+/* { dg-final { cleanup-tree-dump "optimized" } } */

gcc/tree-ssa-ccp.c

@@ -306,6 +306,12 @@ get_symbol_constant_value (tree sym)
       if (val
 	  && ccp_decl_initial_min_invariant (val))
 	return val;
+      /* Variables declared 'const' without an initializer
+	 have zero as the intializer.  */
+      if (!val
+          && (INTEGRAL_TYPE_P (TREE_TYPE (sym))
+	       || SCALAR_FLOAT_TYPE_P (TREE_TYPE (sym))))
+        return fold_convert (TREE_TYPE (sym), integer_zero_node);
     }
 
   return NULL_TREE;