# HG changeset patch # User pgovereau # Date 1413216726 14400 # Node ID c14f94b48e30db5e5849f8c8c62c34a2c720e560 # Parent 36889255488f0cd8375eb6158e4e66fe3b40f378 8060234: Fix push for JDK-8058243 Reviewed-by: jjg, vromero diff -r 36889255488f -r c14f94b48e30 langtools/src/jdk.compiler/share/classes/com/sun/tools/javac/jvm/Gen.java --- a/langtools/src/jdk.compiler/share/classes/com/sun/tools/javac/jvm/Gen.java Mon Oct 13 17:22:47 2014 +0200 +++ b/langtools/src/jdk.compiler/share/classes/com/sun/tools/javac/jvm/Gen.java Mon Oct 13 12:12:06 2014 -0400 @@ -1225,8 +1225,8 @@ // consider the size of the bytecode. // A discussion of the metric can be found here: // http://mail.openjdk.java.net/pipermail/compiler-dev/2014-September/008987.html - int table_cost = 4 + (hi - lo + 1); // words - int lookup_cost = 3 + 2 * nlabels; + long table_cost = 4 + ((long)hi - lo + 1); // words + long lookup_cost = 3 + 2 * (long)nlabels; int opcode = table_cost <= lookup_cost ? tableswitch : lookupswitch; int startpc = code.curCP(); // the position of the selector operation diff -r 36889255488f -r c14f94b48e30 langtools/test/tools/javac/SwitchMetricTest.java --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/langtools/test/tools/javac/SwitchMetricTest.java Mon Oct 13 12:12:06 2014 -0400 @@ -0,0 +1,88 @@ +/* + * Copyright (c) 2014, 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. + */ + +/* + * @test + * @bug 8058243 + * @summary Reduce size of bytecode for large switch statements + * @library /tools/lib + * @build ToolBox + * @run main SwitchMetricTest + */ + +import java.net.URL; +import java.util.List; + +public class SwitchMetricTest { + public static void main(String... args) throws Exception { + new SwitchMetricTest().run(); + } + + // This code should produce a tableswitch + class Test1 { + int m(int x) { + switch (x) { + case 1: + case 2: + case 3: + case 4: + case 5: return 1; + default: return 0; + } + } + } + + // This code should produce a lookupswitch + class Test2 { + int m(int x) { + switch (x) { + case 1: + case 2: + case 3: + case 4: + case 50: return 1; + default: return 0; + } + } + } + + void check(String classfile, String bytecode) throws Exception { + ToolBox tb = new ToolBox(); + URL url = SwitchMetricTest.class.getResource(classfile); + List result = tb.new JavapTask() + .options("-c") + .classes(url.getFile()) + .run() + .write(ToolBox.OutputKind.DIRECT) + .getOutputLines(ToolBox.OutputKind.DIRECT); + + List matches = tb.grep(bytecode, result); + if (matches.isEmpty()) + throw new Exception(bytecode + " not found"); + } + + void run() throws Exception { + check("SwitchMetricTest$Test1.class", "tableswitch"); + check("SwitchMetricTest$Test2.class", "lookupswitch"); + } +}