1 files changed, 33 insertions, 22 deletions

diff --git a/src/jdk/nashorn/internal/ir/TernaryNode.java b/src/jdk/nashorn/internal/ir/TernaryNode.java
index 26c14b76..913262d9 100644
--- a/src/jdk/nashorn/internal/ir/TernaryNode.java
+++ b/src/jdk/nashorn/internal/ir/TernaryNode.java
@@ -25,20 +25,23 @@
 
 package jdk.nashorn.internal.ir;
 
+import java.util.function.Function;
+import jdk.nashorn.internal.codegen.types.Type;
 import jdk.nashorn.internal.ir.annotations.Immutable;
 import jdk.nashorn.internal.ir.visitor.NodeVisitor;
+import jdk.nashorn.internal.parser.TokenType;
 
 /**
- * TernaryNode nodes represent three operand operations (?:).
+ * TernaryNode represent the ternary operator {@code ?:}. Note that for control-flow calculation reasons its branch
+ * expressions (but not its test expression) are always wrapped in instances of {@link JoinPredecessorExpression}.
  */
 @Immutable
 public final class TernaryNode extends Expression {
-    private final Expression test;
-
-    private final Expression trueExpr;
+    private static final long serialVersionUID = 1L;
 
-    /** Third argument. */
-    private final Expression falseExpr;
+    private final Expression test;
+    private final JoinPredecessorExpression trueExpr;
+    private final JoinPredecessorExpression falseExpr;
 
     /**
      * Constructor
@@ -48,14 +51,15 @@ public final class TernaryNode extends Expression {
      * @param trueExpr  expression evaluated when test evaluates to true
      * @param falseExpr expression evaluated when test evaluates to true
      */
-    public TernaryNode(final long token, final Expression test, final Expression trueExpr, final Expression falseExpr) {
+    public TernaryNode(final long token, final Expression test, final JoinPredecessorExpression trueExpr, final JoinPredecessorExpression falseExpr) {
         super(token, falseExpr.getFinish());
         this.test = test;
         this.trueExpr = trueExpr;
         this.falseExpr = falseExpr;
     }
 
-    private TernaryNode(final TernaryNode ternaryNode, final Expression test, final Expression trueExpr, final Expression falseExpr) {
+    private TernaryNode(final TernaryNode ternaryNode, final Expression test, final JoinPredecessorExpression trueExpr,
+            final JoinPredecessorExpression falseExpr) {
         super(ternaryNode);
         this.test = test;
         this.trueExpr = trueExpr;
@@ -66,24 +70,25 @@ public final class TernaryNode extends Expression {
     public Node accept(final NodeVisitor<? extends LexicalContext> visitor) {
         if (visitor.enterTernaryNode(this)) {
             final Expression newTest = (Expression)getTest().accept(visitor);
-            final Expression newTrueExpr = (Expression)getTrueExpression().accept(visitor);
-            final Expression newFalseExpr = (Expression)falseExpr.accept(visitor);
-            return visitor.leaveTernaryNode(setTest(newTest).setTrueExpression(newTrueExpr).setFalseExpression1(newFalseExpr));
+            final JoinPredecessorExpression newTrueExpr = (JoinPredecessorExpression)trueExpr.accept(visitor);
+            final JoinPredecessorExpression newFalseExpr = (JoinPredecessorExpression)falseExpr.accept(visitor);
+            return visitor.leaveTernaryNode(setTest(newTest).setTrueExpression(newTrueExpr).setFalseExpression(newFalseExpr));
         }
 
         return this;
     }
 
     @Override
-    public void toString(final StringBuilder sb) {
-        final boolean testParen  = tokenType().needsParens(getTest().tokenType(), true);
-        final boolean trueParen  = tokenType().needsParens(getTrueExpression().tokenType(), false);
-        final boolean falseParen = tokenType().needsParens(getFalseExpression().tokenType(), false);
+    public void toString(final StringBuilder sb, final boolean printType) {
+        final TokenType tokenType  = tokenType();
+        final boolean   testParen  = tokenType.needsParens(getTest().tokenType(), true);
+        final boolean   trueParen  = tokenType.needsParens(getTrueExpression().tokenType(), false);
+        final boolean   falseParen = tokenType.needsParens(getFalseExpression().tokenType(), false);
 
         if (testParen) {
             sb.append('(');
         }
-        getTest().toString(sb);
+        getTest().toString(sb, printType);
         if (testParen) {
             sb.append(')');
         }
@@ -93,7 +98,7 @@ public final class TernaryNode extends Expression {
         if (trueParen) {
             sb.append('(');
         }
-        getTrueExpression().toString(sb);
+        getTrueExpression().toString(sb, printType);
         if (trueParen) {
             sb.append(')');
         }
@@ -103,7 +108,7 @@ public final class TernaryNode extends Expression {
         if (falseParen) {
             sb.append('(');
         }
-        getFalseExpression().toString(sb);
+        getFalseExpression().toString(sb, printType);
         if (falseParen) {
             sb.append(')');
         }
@@ -116,6 +121,12 @@ public final class TernaryNode extends Expression {
                 && getFalseExpression().isLocal();
     }
 
+    @Override
+    public Type getType(final Function<Symbol, Type> localVariableTypes) {
+        return Type.widestReturnType(getTrueExpression().getType(localVariableTypes), getFalseExpression().getType(localVariableTypes));
+    }
+
+
     /**
      * Get the test expression for this ternary expression, i.e. "x" in x ? y : z
      * @return the test expression
@@ -128,7 +139,7 @@ public final class TernaryNode extends Expression {
      * Get the true expression for this ternary expression, i.e. "y" in x ? y : z
      * @return the true expression
      */
-    public Expression getTrueExpression() {
+    public JoinPredecessorExpression getTrueExpression() {
         return trueExpr;
     }
 
@@ -136,7 +147,7 @@ public final class TernaryNode extends Expression {
      * Get the false expression for this ternary expression, i.e. "z" in x ? y : z
      * @return the false expression
      */
-    public Expression getFalseExpression() {
+    public JoinPredecessorExpression getFalseExpression() {
         return falseExpr;
     }
 
@@ -157,7 +168,7 @@ public final class TernaryNode extends Expression {
      * @param trueExpr new true expression
      * @return a node equivalent to this one except for the requested change.
      */
-    public TernaryNode setTrueExpression(final Expression trueExpr) {
+    public TernaryNode setTrueExpression(final JoinPredecessorExpression trueExpr) {
         if (this.trueExpr == trueExpr) {
             return this;
         }
@@ -169,7 +180,7 @@ public final class TernaryNode extends Expression {
      * @param falseExpr new false expression
      * @return a node equivalent to this one except for the requested change.
      */
-    public TernaryNode setFalseExpression1(final Expression falseExpr) {
+    public TernaryNode setFalseExpression(final JoinPredecessorExpression falseExpr) {
         if (this.falseExpr == falseExpr) {
             return this;
         }