157         @Override
 158         protected ConcurrentMap<NashornCallSiteDescriptor, NashornCallSiteDescriptor> computeValue(final Class<?> type) {
 159             return new ConcurrentHashMap<>();
 160         }
 161     };
 162 
 163     private static final AccessControlContext GET_LOOKUP_PERMISSION_CONTEXT =
 164             AccessControlContextFactory.createAccessControlContext(CallSiteDescriptor.GET_LOOKUP_PERMISSION_NAME);
 165 
 166     @SuppressWarnings("unchecked")
 167     private static final Map<String, Reference<NamedOperation>>[] NAMED_OPERATIONS =
 168             Stream.generate(() -> Collections.synchronizedMap(new WeakHashMap<>()))
 169             .limit(OPERATIONS.length).toArray(Map[]::new);
 170 
 171     private final int flags;
 172 
 173     /**
 174      * Function used by {@link NashornTextifier} to represent call site flags in
 175      * human readable form
 176      * @param flags call site flags
 177      * @return human readable form of this callsite descriptor
 178      */
 179     public static String toString(final int flags) {
 180         final StringBuilder sb = new StringBuilder();



 181         if ((flags & CALLSITE_SCOPE) != 0) {
 182             if ((flags & CALLSITE_FAST_SCOPE) != 0) {
 183                 sb.append("fastscope ");
 184             } else {
 185                 assert (flags & CALLSITE_FAST_SCOPE) == 0 : "can't be fastscope without scope";
 186                 sb.append("scope ");
 187             }
 188             if ((flags & CALLSITE_DECLARE) != 0) {
 189                 sb.append("declare ");
 190             }


 191         }
 192         if ((flags & CALLSITE_APPLY_TO_CALL) != 0) {
 193             sb.append("apply2call ");
 194         }
 195         if ((flags & CALLSITE_STRICT) != 0) {
 196             sb.append("strict ");
 197         }
 198         return sb.length() == 0 ? "" : " " + sb.toString().trim();
 199     }
 200 
 201     /**
 202      * Given call site flags, returns the operation name encoded in them.
 203      * @param flags flags
 204      * @return the operation name
 205      */
 206     public static String getOperationName(final int flags) {
 207         switch(flags & OPERATION_MASK) {
 208         case 0: return "GET_PROPERTY";
 209         case 1: return "GET_ELEMENT";
 210         case 2: return "GET_METHOD_PROPERTY";
 211         case 3: return "GET_METHOD_ELEMENT";
 212         case 4: return "SET_PROPERTY";
 213         case 5: return "SET_ELEMENT";
 214         case 6: return "CALL";
 215         case 7: return "NEW";
 216         default: throw new AssertionError();
 217         }
 218     }

 157         @Override
 158         protected ConcurrentMap<NashornCallSiteDescriptor, NashornCallSiteDescriptor> computeValue(final Class<?> type) {
 159             return new ConcurrentHashMap<>();
 160         }
 161     };
 162 
 163     private static final AccessControlContext GET_LOOKUP_PERMISSION_CONTEXT =
 164             AccessControlContextFactory.createAccessControlContext(CallSiteDescriptor.GET_LOOKUP_PERMISSION_NAME);
 165 
 166     @SuppressWarnings("unchecked")
 167     private static final Map<String, Reference<NamedOperation>>[] NAMED_OPERATIONS =
 168             Stream.generate(() -> Collections.synchronizedMap(new WeakHashMap<>()))
 169             .limit(OPERATIONS.length).toArray(Map[]::new);
 170 
 171     private final int flags;
 172 
 173     /**
 174      * Function used by {@link NashornTextifier} to represent call site flags in
 175      * human readable form
 176      * @param flags call site flags
 177      * @param sb the string builder
 178      */
 179     public static void appendFlags(final int flags, final StringBuilder sb) {
 180         final int pp = flags >> CALLSITE_PROGRAM_POINT_SHIFT;
 181         if (pp != 0) {
 182             sb.append(" pp=").append(pp);
 183         }
 184         if ((flags & CALLSITE_SCOPE) != 0) {
 185             if ((flags & CALLSITE_FAST_SCOPE) != 0) {
 186                 sb.append(" fastscope");
 187             } else {
 188                 sb.append(" scope");

 189             }
 190             if ((flags & CALLSITE_DECLARE) != 0) {
 191                 sb.append(" declare");
 192             }
 193         } else {
 194             assert (flags & CALLSITE_FAST_SCOPE) == 0 : "can't be fastscope without scope";
 195         }
 196         if ((flags & CALLSITE_APPLY_TO_CALL) != 0) {
 197             sb.append(" apply2call");
 198         }
 199         if ((flags & CALLSITE_STRICT) != 0) {
 200             sb.append(" strict");
 201         }

 202     }
 203 
 204     /**
 205      * Given call site flags, returns the operation name encoded in them.
 206      * @param flags flags
 207      * @return the operation name
 208      */
 209     public static String getOperationName(final int flags) {
 210         switch(flags & OPERATION_MASK) {
 211         case 0: return "GET_PROPERTY";
 212         case 1: return "GET_ELEMENT";
 213         case 2: return "GET_METHOD_PROPERTY";
 214         case 3: return "GET_METHOD_ELEMENT";
 215         case 4: return "SET_PROPERTY";
 216         case 5: return "SET_ELEMENT";
 217         case 6: return "CALL";
 218         case 7: return "NEW";
 219         default: throw new AssertionError();
 220         }
 221     }