Fix -Wenum-compare-switch warning in i386.c.

2019-04-30  Martin Liska  <mliska@suse.cz>

	* config/i386/i386.c (ix86_builtin_reciprocal): Cast
	DECL_FUNCTION_CODE into ix86_builtins enum before
	the switch statement.

From-SVN: r270681

gcc/ChangeLog

+2019-04-30  Martin Liska  <mliska@suse.cz>
+
+	* config/i386/i386.c (ix86_builtin_reciprocal): Cast
+	DECL_FUNCTION_CODE into ix86_builtins enum before
+	the switch statement.
+
 2019-04-30  Jakub Jelinek  <jakub@redhat.com>
 
 	PR tree-optimization/89475

gcc/config/i386/i386.c

@@ -39382,7 +39382,9 @@ use_rsqrt_p ()
 static tree
 ix86_builtin_reciprocal (tree fndecl)
 {
-  switch (DECL_FUNCTION_CODE (fndecl))
+  enum ix86_builtins fn_code
+    = (enum ix86_builtins) DECL_FUNCTION_CODE (fndecl);
+  switch (fn_code)
     {
       /* Vectorized version of sqrt to rsqrt conversion.  */
     case IX86_BUILTIN_SQRTPS_NR: