diff --git a/tool/src/org/antlr/v4/codegen/model/InvokeRule.java b/tool/src/org/antlr/v4/codegen/model/InvokeRule.java
index efa39a68b..5649a138f 100644
--- a/tool/src/org/antlr/v4/codegen/model/InvokeRule.java
+++ b/tool/src/org/antlr/v4/codegen/model/InvokeRule.java
@@ -48,7 +48,7 @@ public class InvokeRule extends RuleElement implements LabeledOp {
 
 	@ModelElement public List<ActionChunk> argExprsChunks;
 
-	public InvokeRule(OutputModelFactory factory, GrammarAST ast, GrammarAST labelAST) {
+	public InvokeRule(ParserFactory factory, GrammarAST ast, GrammarAST labelAST) {
 		super(factory, ast);
 		if ( ast.atnState!=null ) {
 			RuleTransition ruleTrans = (RuleTransition)ast.atnState.transition(0);
@@ -65,14 +65,17 @@ public class InvokeRule extends RuleElement implements LabeledOp {
 		if ( labelAST!=null ) {
 			// for x=r, define <rule-context-type> x and list_x
 			String label = labelAST.getText();
-			RuleContextDecl d = new RuleContextDecl(factory,label,ctxName);
-			labels.add(d);
-			rf.addContextDecl(ast.getAltLabel(), d);
 			if ( labelAST.parent.getType() == ANTLRParser.PLUS_ASSIGN  ) {
+				factory.defineImplicitLabel(ast, this);
 				String listLabel = gen.target.getListLabel(label);
 				RuleContextListDecl l = new RuleContextListDecl(factory, listLabel, ctxName);
 				rf.addContextDecl(ast.getAltLabel(), l);
 			}
+			else {
+				RuleContextDecl d = new RuleContextDecl(factory,label,ctxName);
+				labels.add(d);
+				rf.addContextDecl(ast.getAltLabel(), d);
+			}
 		}
 		if ( ast.getChildCount()>0 ) {
 			ActionAST arg = (ActionAST)ast.getChild(0);
diff --git a/tool/test/org/antlr/v4/test/TestParserExec.java b/tool/test/org/antlr/v4/test/TestParserExec.java
index 4f641034c..9f3c6622b 100644
--- a/tool/test/org/antlr/v4/test/TestParserExec.java
+++ b/tool/test/org/antlr/v4/test/TestParserExec.java
@@ -34,6 +34,21 @@ import org.junit.Test;
  *  the remaining input to match.
  */
 public class TestParserExec extends BaseTest {
+	@Test public void testLabels() throws Exception {
+		String grammar =
+			"grammar T;\n" +
+			"a : b1=b b2+=b*;\n" +
+			"b : id=ID val+=INT*;\n" +
+			"ID : 'a'..'z'+ ;\n" +
+			"INT : '0'..'9'+;\n" +
+			"WS : (' '|'\\n') {skip();} ;\n";
+
+		String found = execParser("T.g", grammar, "TParser", "TLexer", "a",
+								  "abc 34", false);
+		assertEquals("", found);
+		assertEquals(null, stderrDuringParse);
+	}
+
 	@Test public void testBasic() throws Exception {
 		String grammar =
 			"grammar T;\n" +
diff --git a/tool/test/org/antlr/v4/test/TestPerformance.java b/tool/test/org/antlr/v4/test/TestPerformance.java
index 2740bc1b8..c6c7afc86 100644
--- a/tool/test/org/antlr/v4/test/TestPerformance.java
+++ b/tool/test/org/antlr/v4/test/TestPerformance.java
@@ -44,7 +44,9 @@ import java.net.URLClassLoader;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collection;
+import java.util.HashSet;
 import java.util.List;
+import java.util.Set;
 import java.util.logging.Level;
 import java.util.logging.Logger;
 import org.antlr.v4.runtime.atn.ATNConfig;
@@ -298,6 +300,8 @@ public class TestPerformance extends BaseTest {
 
             if (SHOW_DFA_STATE_STATS) {
                 int states = 0;
+				int configs = 0;
+				Set<ATNConfig> uniqueConfigs = new HashSet<ATNConfig>();
 
                 for (int i = 0; i < decisionToDFA.length; i++) {
                     DFA dfa = decisionToDFA[i];
@@ -306,9 +310,13 @@ public class TestPerformance extends BaseTest {
                     }
 
                     states += dfa.states.size();
+					for (DFAState state : dfa.states.values()) {
+						configs += state.configset.size();
+						uniqueConfigs.addAll(state.configset);
+					}
                 }
 
-                System.out.format("There are %d DFAState instances.\n", states);
+                System.out.format("There are %d DFAState instances, %d configs (%d unique).\n", states, configs, uniqueConfigs.size());
             }
 
             int localDfaCount = 0;
@@ -418,7 +426,7 @@ public class TestPerformance extends BaseTest {
             @SuppressWarnings({"unchecked"})
             final Class<? extends Parser> parserClass = (Class<? extends Parser>)loader.loadClass("JavaParser");
             @SuppressWarnings({"unchecked"})
-            final Class<? extends ParseTreeListener<Token>> listenerClass = (Class<? extends ParseTreeListener<Token>>)loader.loadClass("BlankJavaListener");
+            final Class<? extends ParseTreeListener<Token>> listenerClass = (Class<? extends ParseTreeListener<Token>>)loader.loadClass("JavaBaseListener");
             TestPerformance.sharedListener = listenerClass.newInstance();
 
             final Constructor<? extends Lexer> lexerCtor = lexerClass.getConstructor(CharStream.class);