8134490: Dead var statement evacuation incorrectly descends into nested functions
Reviewed-by: hannesw, mhaupt
--- a/nashorn/src/jdk.scripting.nashorn/share/classes/jdk/nashorn/internal/codegen/FindScopeDepths.java Fri Sep 25 16:01:54 2015 +0530
+++ b/nashorn/src/jdk.scripting.nashorn/share/classes/jdk/nashorn/internal/codegen/FindScopeDepths.java Fri Sep 25 12:46:53 2015 +0200
@@ -275,15 +275,11 @@
final Set<Symbol> symbols = new HashSet<>();
block.accept(new NodeVisitor<LexicalContext>(new LexicalContext()) {
@Override
- public final boolean enterDefault(final Node node) {
- if (!compiler.isOnDemandCompilation()) {
- if (node instanceof IdentNode) {
- final Symbol symbol = ((IdentNode)node).getSymbol();
- if (symbol != null && symbol.isScope()) {
- //if this is an internal symbol, skip it.
- symbols.add(symbol);
- }
- }
+ public boolean enterIdentNode(final IdentNode identNode) {
+ final Symbol symbol = identNode.getSymbol();
+ if (symbol != null && symbol.isScope()) {
+ //if this is an internal symbol, skip it.
+ symbols.add(symbol);
}
return true;
}
--- a/nashorn/src/jdk.scripting.nashorn/share/classes/jdk/nashorn/internal/codegen/Lower.java Fri Sep 25 16:01:54 2015 +0530
+++ b/nashorn/src/jdk.scripting.nashorn/share/classes/jdk/nashorn/internal/codegen/Lower.java Fri Sep 25 12:46:53 2015 +0200
@@ -124,9 +124,18 @@
statement.accept(new NodeVisitor<LexicalContext>(new LexicalContext()) {
@Override
public boolean enterVarNode(final VarNode varNode) {
+ // We can't entirely eliminate dead statements, as var declarations are scoped
+ // to the whole function so we need to preserve them although without
+ // initializers.
newStatements.add(varNode.setInit(null));
return false;
}
+
+ @Override
+ public boolean enterFunctionNode(final FunctionNode functionNode) {
+ // Don't descend into nested functions when searching for VarNodes, though.
+ return false;
+ }
});
}
}
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/nashorn/test/script/basic/JDK-8134490.js Fri Sep 25 12:46:53 2015 +0200
@@ -0,0 +1,41 @@
+/*
+ * Copyright (c) 2015 Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+/**
+ * JDK-8134490: Dead var statement evacuation incorrectly descends into nested functions
+ *
+ * @test
+ * @run
+ */
+
+var v1;
+
+function f1()
+{
+v1 = 1;
+return true;
+(function () { var v1; })();
+}
+
+f1();
+// If it executes without throwing an exception in code generator, it's working.