changeset 53237:041f1cbdae3e

8215410: Regression test for JDK-8214994 Summary: Added a regression test for 8214994 which was fixed by accident with 8211451. Reviewed-by: kvn
author thartmann
date Mon, 17 Dec 2018 08:25:57 +0100
parents 83840e83476a
children 7aa1a37b04a2
files test/hotspot/jtreg/compiler/loopopts/TestSplitIfOpaque1.java
diffstat 1 files changed, 97 insertions(+), 0 deletions(-) [+]
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--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/test/hotspot/jtreg/compiler/loopopts/TestSplitIfOpaque1.java	Mon Dec 17 08:25:57 2018 +0100
@@ -0,0 +1,97 @@
+/*
+ * Copyright (c) 2018, 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 8214994
+ * @summary The split-if optimization fails because an unexpected Opaque1 is encountered.
+ * @run main/othervm -XX:+IgnoreUnrecognizedVMOptions -XX:-UseOnStackReplacement -XX:-BackgroundCompilation
+ *                   compiler.loopopts.TestSplitIfOpaque1
+ */
+
+package compiler.loopopts;
+
+public class TestSplitIfOpaque1 {
+
+    static class MyClass {
+        int f;
+        MyClass(int f) {
+            this.f = f;
+        }
+    }
+
+    // The inner loop is found to be a counted loop and a loop limit check
+    // is added by updating the Opaque1 input of the predicate template.
+    // This Opaque1 node is then pushed upwards to before the predicates of
+    // the outer loop and ends up right after the second 'if (b)'.
+    // The split-if optimization kicks in and splits the first predicate of
+    // the outer loop (an "obj != NULL" check) through the 'if (b)' region.
+    // We fail because the region contains an unexpected Opaque1 node.
+    static int test1(boolean b, int limit, MyClass obj) {
+        int res = 0;
+        MyClass notNull = new MyClass(42);
+        if (b) {
+            limit = 100;
+        }
+        if (b) {
+            obj = notNull;
+        }
+        for (int i = 0; i < 1000; ++i) {
+            res += obj.f;
+            for (int j = 0; j <= limit; ++j) {
+                // Empty
+            }
+        }
+        return res;
+    }
+
+    // Same as test1 but triggers slightly different failure mode
+    static int test2(boolean b, int limit, MyClass obj, int[] array) {
+        int res = 0;
+        MyClass notNull = new MyClass(12);
+        if (b) {
+            limit = 100;
+        }
+        if (b) {
+            obj = notNull;
+        }
+        for (int i = 0; i < 1000; ++i) {
+            res += obj.f;
+            for (int j = 0; j <= limit; ++j) {
+                array[j] = j;
+            }
+        }
+        return res;
+    }
+
+    public static void main(String[] args) {
+        MyClass obj = new MyClass(42);
+        int[] array = new int[101];
+        for (int i = 0; i < 20_000; i++) {
+            test1(true, 50, obj);
+            test1(false, 100, obj);
+            test2(true, 50, obj, array);
+            test2(false, 100, obj, array);
+        }
+    }
+}