1 files changed, 55 insertions, 0 deletions
diff --git a/gcc/tree.c b/gcc/tree.c
index 9a6e000..76cba27 100644
--- a/gcc/tree.c
+++ b/gcc/tree.c
@@ -6258,6 +6258,61 @@ build_complex_type (tree component_type)
 
   return build_qualified_type (t, TYPE_QUALS (component_type));
 }
+
+/* If TYPE is a real or complex floating-point type and the target
+   does not directly support arithmetic on TYPE then return the wider
+   type to be used for arithmetic on TYPE.  Otherwise, return
+   NULL_TREE.  */
+
+tree
+excess_precision_type (tree type)
+{
+  if (flag_excess_precision != EXCESS_PRECISION_FAST)
+    {
+      int flt_eval_method = TARGET_FLT_EVAL_METHOD;
+      switch (TREE_CODE (type))
+	{
+	case REAL_TYPE:
+	  switch (flt_eval_method)
+	    {
+	    case 1:
+	      if (TYPE_MODE (type) == TYPE_MODE (float_type_node))
+		return double_type_node;
+	      break;
+	    case 2:
+	      if (TYPE_MODE (type) == TYPE_MODE (float_type_node)
+		  || TYPE_MODE (type) == TYPE_MODE (double_type_node))
+		return long_double_type_node;
+	      break;
+	    default:
+	      gcc_unreachable ();
+	    }
+	  break;
+	case COMPLEX_TYPE:
+	  if (TREE_CODE (TREE_TYPE (type)) != REAL_TYPE)
+	    return NULL_TREE;
+	  switch (flt_eval_method)
+	    {
+	    case 1:
+	      if (TYPE_MODE (TREE_TYPE (type)) == TYPE_MODE (float_type_node))
+		return complex_double_type_node;
+	      break;
+	    case 2:
+	      if (TYPE_MODE (TREE_TYPE (type)) == TYPE_MODE (float_type_node)
+		  || (TYPE_MODE (TREE_TYPE (type))
+		      == TYPE_MODE (double_type_node)))
+		return complex_long_double_type_node;
+	      break;
+	    default:
+	      gcc_unreachable ();
+	    }
+	  break;
+	default:
+	  break;
+	}
+    }
+  return NULL_TREE;
+}
 
 /* Return OP, stripped of any conversions to wider types as much as is safe.
    Converting the value back to OP's type makes a value equivalent to OP.