changeset 2664:9e6a9d5a3551

8060234: Fix push for JDK-8058243 Reviewed-by: jjg, vromero
author pgovereau
date Mon, 13 Oct 2014 12:12:06 -0400
parents b5d44ecef54d
children 76b58486b9d5
files src/jdk.compiler/share/classes/com/sun/tools/javac/jvm/Gen.java test/tools/javac/SwitchMetricTest.java
diffstat 2 files changed, 90 insertions(+), 2 deletions(-) [+]
line wrap: on
line diff
--- a/src/jdk.compiler/share/classes/com/sun/tools/javac/jvm/Gen.java	Mon Oct 13 17:22:47 2014 +0200
+++ b/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
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/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<String> result = tb.new JavapTask()
+                .options("-c")
+                .classes(url.getFile())
+                .run()
+                .write(ToolBox.OutputKind.DIRECT)
+                .getOutputLines(ToolBox.OutputKind.DIRECT);
+
+        List<String> 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");
+    }
+}