Move constants to enum from static final byte FOO.

Author: arnsholt

src/vm/jvm/runtime/org/perl6/nqp/sixmodel/reprs/NativeCallInstance.java

@@ -5,29 +5,31 @@
 import org.perl6.nqp.sixmodel.SixModelObject;
 
 public class NativeCallInstance extends SixModelObject {
-    /* Constants. Might be more idiomatic Java to move these to an enum. */
-    public static final byte ARG_VOID      = 0;
-    public static final byte ARG_CHAR      = 2;
-    public static final byte ARG_SHORT     = 4;
-    public static final byte ARG_INT       = 6;
-    public static final byte ARG_LONG      = 8;
-    public static final byte ARG_LONGLONG  = 10;
-    public static final byte ARG_FLOAT     = 12;
-    public static final byte ARG_DOUBLE    = 14;
-    public static final byte ARG_ASCIISTR  = 16;
-    public static final byte ARG_UTF8STR   = 18;
-    public static final byte ARG_UTF16STR  = 20;
-    public static final byte ARG_CSTRUCT   = 22;
-    public static final byte ARG_CARRAY    = 24;
-    public static final byte ARG_CALLBACK  = 26;
-    public static final byte ARG_CPOINTER  = 28;
-    public static final byte ARG_TYPE_MASK = 30;
-
     /* Flag for whether we should free a string after passing it or not. These
      * are going away once the array handling is refactored.*/
     public static final byte ARG_NO_FREE_STR   = 0;
     public static final byte ARG_FREE_STR      = 1;
     public static final byte ARG_FREE_STR_MASK = 1;
 
     public Function entry_point;
+    public ArgType[]   arg_types;
+    public ArgType     ret_type;
+
+    public enum ArgType {
+        VOID,
+        CHAR,
+        SHORT,
+        INT,
+        LONG,
+        LONGLONG,
+        FLOAT,
+        DOUBLE,
+        ASCIISTR,
+        UTF8STR,
+        UTF16STR,
+        CSTRUCT,
+        CARRAY,
+        CALLBACK,
+        CPOINTER;
+    }
 }