Add tag members to wasm instance exports.

Author: woess

wasm/src/org.graalvm.wasm/src/org/graalvm/wasm/WasmInstanceExports.java

@@ -90,6 +90,10 @@ public Object readMember(String member) throws UnknownIdentifierException {
         if (globalIndex != null) {
             return instance.externalGlobal(globalIndex);
         }
+        final Integer tagIndex = symbolTable.exportedTags().get(member);
+        if (tagIndex != null) {
+            return instance.tag(tagIndex);
+        }
         throw UnknownIdentifierException.create(member);
     }
 
@@ -100,7 +104,8 @@ boolean isMemberReadable(String member) {
         return symbolTable.exportedFunctions().containsKey(member) ||
                         symbolTable.exportedMemories().containsKey(member) ||
                         symbolTable.exportedTables().containsKey(member) ||
-                        symbolTable.exportedGlobals().containsKey(member);
+                        symbolTable.exportedGlobals().containsKey(member) ||
+                        symbolTable.exportedTags().containsKey(member);
     }
 
     @ExportMessage
@@ -145,6 +150,9 @@ Object getMembers(@SuppressWarnings("unused") boolean includeInternal) {
         for (String globalName : symbolTable.exportedGlobals().getKeys()) {
             exportNames.add(globalName);
         }
+        for (String globalName : symbolTable.exportedTags().getKeys()) {
+            exportNames.add(globalName);
+        }
         return new Sequence<>(exportNames);
     }