Implement evolution_function_right_is_integer_cst.

2009-07-30  Sebastian Pop  <sebastian.pop@amd.com>

	* tree-chrec.c (evolution_function_right_is_integer_cst): New.
	* tree-chrec.h (evolution_function_right_is_integer_cst): Declared.

From-SVN: r150299

gcc/ChangeLog

 2009-07-30  Sebastian Pop  <sebastian.pop@amd.com>
 
+	* tree-chrec.c (evolution_function_right_is_integer_cst): New.
+	* tree-chrec.h (evolution_function_right_is_integer_cst): Declared.
+
+2009-07-30  Sebastian Pop  <sebastian.pop@amd.com>
+
 	* tree-chrec.c (operator_is_linear): Handle BIT_NOT_EXPR.
 	(scev_is_linear_expression): Return false if the evolution is not
 	affine multivariate.

gcc/tree-chrec.c

@@ -1487,3 +1487,33 @@ scev_is_linear_expression (tree scev)
       return false;
     }
 }
+
+/* Determines whether the expression CHREC contains only interger consts
+   in the right parts.  */
+
+bool
+evolution_function_right_is_integer_cst (const_tree chrec)
+{
+  if (chrec == NULL_TREE)
+    return false;
+
+  switch (TREE_CODE (chrec))
+    {
+    case INTEGER_CST:
+      return true;
+
+    case POLYNOMIAL_CHREC:
+      if (!evolution_function_right_is_integer_cst (CHREC_RIGHT (chrec)))
+	return false;
+
+      if (TREE_CODE (CHREC_LEFT (chrec)) == POLYNOMIAL_CHREC
+	&& !evolution_function_right_is_integer_cst (CHREC_LEFT (chrec)))
+	return false;
+
+      return true;
+
+    default:
+      return false;
+    }
+}
+

gcc/tree-chrec.h

@@ -86,6 +86,7 @@ extern bool evolution_function_is_univariate_p (const_tree);
 extern unsigned nb_vars_in_chrec (tree);
 extern bool evolution_function_is_invariant_p (tree, int);
 extern bool scev_is_linear_expression (tree);
+extern bool evolution_function_right_is_integer_cst (const_tree);
 
 /* Determines whether CHREC is equal to zero.  */