8025515: Performance issues with Source.getLine()

Reviewed-by: sundar, lagergren

nashorn/src/jdk/nashorn/internal/codegen/CodeGenerator.java

@@ -1956,7 +1956,7 @@ final class CodeGenerator extends NodeOperatorVisitor<CodeGeneratorLexicalContex
 
         final Expression expression = throwNode.getExpression();
         final int        position   = throwNode.position();
-        final int        line       = source.getLine(position);
+        final int        line       = throwNode.getLineNumber();
         final int        column     = source.getColumn(position);
 
         load(expression);

nashorn/src/jdk/nashorn/internal/ir/LexicalContext.java

@@ -587,11 +587,11 @@ public class LexicalContext {
                 final FunctionNode fn = (FunctionNode)node;
                 final Source source = fn.getSource();
                 String src = source.toString();
-                if (src.indexOf(File.pathSeparator) != -1) {
+                if (src.contains(File.pathSeparator)) {
                     src = src.substring(src.lastIndexOf(File.pathSeparator));
                 }
                 src += ' ';
-                src += source.getLine(fn.getStart());
+                src += fn.getLineNumber();
                 sb.append(src);
             }
             sb.append(' ');

nashorn/src/jdk/nashorn/internal/parser/Parser.java

@@ -2436,7 +2436,7 @@ loop:
         // name is null, generate anonymous name
         boolean isAnonymous = false;
         if (name == null) {
-            final String tmpName = "_L" + source.getLine(Token.descPosition(token));
+            final String tmpName = "_L" + functionLine;
             name = new IdentNode(functionToken, Token.descPosition(functionToken), tmpName);
             isAnonymous = true;
         }

nashorn/src/jdk/nashorn/internal/runtime/RecompilableScriptFunctionData.java

@@ -132,7 +132,7 @@ public final class RecompilableScriptFunctionData extends ScriptFunctionData {
         if (source != null) {
             sb.append(source.getName())
                 .append(':')
-                .append(source.getLine(Token.descPosition(token)))
+                .append(functionNode.getLineNumber())
                 .append(' ');
         }
 

nashorn/src/jdk/nashorn/internal/runtime/Source.java

@@ -272,6 +272,10 @@ public final class Source {
 
     /**
      * Return line number of character position.
+     *
+     * <p>This method can be expensive for large sources as it iterates through
+     * all characters up to {@code position}.</p>
+     *
      * @param position Position of character in source content.
      * @return Line number.
      */

nashorn/test/script/basic/JDK-8025515.js

@@ -0,0 +1,58 @@
+/*
+ * Copyright (c) 2010, 2013, 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-8025515: Performance issues with Source.getLine()
+ *
+ * @test
+ * @run
+ */
+
+// Make sure synthetic names of anonymous functions have correct line numbers
+
+function testMethodName(f, expected) {
+    try {
+        f();
+        fail("expected error");
+    } catch (e) {
+        var stack = e.getStackTrace();
+        if (stack[0].methodName !== expected) {
+            fail("got " + stack[0].methodName + ", expected " + expected);
+        }
+    }
+}
+
+testMethodName(function() {
+    return a.b.c;
+}, "_L45");
+
+testMethodName(function() { throw new Error() }, "_L49");
+
+var f = (function() {
+    return function() { a.b.c; };
+})();
+testMethodName(f, "_L51$_L52");
+
+testMethodName((function() {
+    return function() { return a.b.c; };
+})(), "_L56$_L57");