8059835: Optimistic splitting doesn't work with let and const
authorhannesw
Tue, 28 Nov 2017 15:36:36 +0100
changeset 47949 002e99dd12f2
parent 47948 8b11e4b32db3
child 47950 9d23fbc3f30c
8059835: Optimistic splitting doesn't work with let and const Reviewed-by: jlaskey, attila
src/jdk.scripting.nashorn/share/classes/jdk/nashorn/internal/codegen/SplitIntoFunctions.java
src/jdk.scripting.nashorn/share/classes/jdk/nashorn/internal/codegen/Splitter.java
src/jdk.scripting.nashorn/share/classes/jdk/nashorn/internal/ir/SplitReturn.java
test/nashorn/script/basic/es6/JDK-8059835.js
--- a/src/jdk.scripting.nashorn/share/classes/jdk/nashorn/internal/codegen/SplitIntoFunctions.java	Mon Nov 27 19:29:00 2017 +0100
+++ b/src/jdk.scripting.nashorn/share/classes/jdk/nashorn/internal/codegen/SplitIntoFunctions.java	Tue Nov 28 15:36:36 2017 +0100
@@ -306,10 +306,10 @@
 
     @Override
     public boolean enterVarNode(final VarNode varNode) {
-        if (!inSplitNode()) {
+        // ES6 block scoped declarations are already placed at their proper position by splitter
+        if (!inSplitNode() || varNode.isBlockScoped()) {
             return super.enterVarNode(varNode);
         }
-        assert !varNode.isBlockScoped(); //TODO: we must handle these too, but we currently don't
 
         final Expression init = varNode.getInit();
 
--- a/src/jdk.scripting.nashorn/share/classes/jdk/nashorn/internal/codegen/Splitter.java	Mon Nov 27 19:29:00 2017 +0100
+++ b/src/jdk.scripting.nashorn/share/classes/jdk/nashorn/internal/codegen/Splitter.java	Tue Nov 28 15:36:36 2017 +0100
@@ -41,6 +41,7 @@
 import jdk.nashorn.internal.ir.SplitNode;
 import jdk.nashorn.internal.ir.Splittable;
 import jdk.nashorn.internal.ir.Statement;
+import jdk.nashorn.internal.ir.VarNode;
 import jdk.nashorn.internal.ir.visitor.SimpleNodeVisitor;
 import jdk.nashorn.internal.runtime.Context;
 import jdk.nashorn.internal.runtime.logging.DebugLogger;
@@ -201,8 +202,9 @@
 
         for (final Statement statement : block.getStatements()) {
             final long weight = WeighNodes.weigh(statement, weightCache);
+            final boolean isBlockScopedVarNode = isBlockScopedVarNode(statement);
 
-            if (statementsWeight + weight >= SPLIT_THRESHOLD || statement.isTerminal()) {
+            if (statementsWeight + weight >= SPLIT_THRESHOLD || statement.isTerminal() || isBlockScopedVarNode) {
                 if (!statements.isEmpty()) {
                     splits.add(createBlockSplitNode(block, function, statements, statementsWeight));
                     statements = new ArrayList<>();
@@ -210,7 +212,7 @@
                 }
             }
 
-            if (statement.isTerminal()) {
+            if (statement.isTerminal() || isBlockScopedVarNode) {
                 splits.add(statement);
             } else {
                 statements.add(statement);
@@ -243,6 +245,10 @@
         return new SplitNode(name, newBlock, compiler.findUnit(weight + WeighNodes.FUNCTION_WEIGHT));
     }
 
+    private boolean isBlockScopedVarNode(final Statement statement) {
+        return statement instanceof VarNode && ((VarNode) statement).isBlockScoped();
+    }
+
     @Override
     public boolean enterBlock(final Block block) {
         if (block.isCatchBlock()) {
--- a/src/jdk.scripting.nashorn/share/classes/jdk/nashorn/internal/ir/SplitReturn.java	Mon Nov 27 19:29:00 2017 +0100
+++ b/src/jdk.scripting.nashorn/share/classes/jdk/nashorn/internal/ir/SplitReturn.java	Tue Nov 28 15:36:36 2017 +0100
@@ -25,6 +25,7 @@
 
 package jdk.nashorn.internal.ir;
 
+import jdk.nashorn.internal.ir.annotations.Ignore;
 import jdk.nashorn.internal.ir.visitor.NodeVisitor;
 
 /**
@@ -37,6 +38,7 @@
     private static final long serialVersionUID = 1L;
 
     /** The sole instance of this AST node. */
+    @Ignore
     public static final SplitReturn INSTANCE = new SplitReturn();
 
     private SplitReturn() {
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/test/nashorn/script/basic/es6/JDK-8059835.js	Tue Nov 28 15:36:36 2017 +0100
@@ -0,0 +1,219 @@
+/*
+ * Copyright (c) 2017, 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-8059835: Optimistic splitting doesn't work with let and const
+ *
+ * @test
+ * @run
+ * @option --language=es6
+ * @option -Dnashorn.compiler.splitter.threshold=100
+ * @fork
+ */
+
+function f() {
+    let sum = 0;
+    const c = 13;
+    if (true) {
+        let x = 0;
+        const y = 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        sum += x;
+        sum += y;
+    }
+    outer: while (true) {
+        let x = 0;
+        const y = 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        sum += x;
+        sum += y;
+        sum += c;
+        let i = 0;
+        const k = 1;
+        while (true) {
+            x += k;
+            if (++i === 10) {
+                break outer;
+            }
+        }
+        x += k;
+    }
+    return sum;
+}
+
+function g() {
+    let sum = 0;
+    const c = 13;
+    if (true) {
+        let x = 0;
+        const y = 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        sum += x;
+        sum += y;
+    }
+    outer: while (true) {
+        let x = 0;
+        const y = 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        x += 1;
+        sum += x;
+        sum += y;
+        sum += c;
+        let i = 0;
+        const k = 1;
+        while (true) {
+            x += k;
+            if (++i === 10) return 'abc';
+        }
+        x += k;
+    }
+    return sum;
+}
+
+Assert.assertTrue(f() === 80);
+Assert.assertTrue(g() === 'abc');