1/*
2 * Copyright (c) 2016, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 */
23package org.graalvm.compiler.replacements.test;
24
25import org.graalvm.compiler.core.test.GraalCompilerTest;
26import org.graalvm.compiler.nodes.ConstantNode;
27import org.graalvm.compiler.nodes.FixedNode;
28import org.graalvm.compiler.nodes.ReturnNode;
29import org.graalvm.compiler.nodes.StructuredGraph;
30import org.graalvm.compiler.nodes.ValueNode;
31import jdk.vm.ci.meta.JavaConstant;
32import org.junit.Test;
33
34import jdk.vm.ci.meta.ResolvedJavaMethod;
35import static org.hamcrest.CoreMatchers.instanceOf;
36import org.junit.Assert;
37
38/**
39 * Tests constant folding of {@link String#hashCode()}.
40 */
41public class StringHashConstantTest extends GraalCompilerTest {
42
43    private static final String A_CONSTANT_STRING = "a constant string";
44
45    private ValueNode asConstant(StructuredGraph graph, String str) {
46        return ConstantNode.forConstant(getSnippetReflection().forObject(str), getMetaAccess(), graph);
47    }
48
49    @Test
50    public void test1() {
51        ResolvedJavaMethod method = getResolvedJavaMethod("parameterizedHashCode");
52        StructuredGraph graph = parseForCompile(method);
53
54        String s = "some string";
55        int expected = s.hashCode();
56        graph.getParameter(0).replaceAndDelete(asConstant(graph, s));
57
58        compile(method, graph);
59
60        FixedNode firstFixed = graph.start().next();
61        Assert.assertThat(firstFixed, instanceOf(ReturnNode.class));
62
63        ReturnNode ret = (ReturnNode) firstFixed;
64        JavaConstant result = ret.result().asJavaConstant();
65        if (result == null) {
66            Assert.fail("result not constant: " + ret.result());
67        } else {
68            Assert.assertEquals("result", expected, result.asInt());
69        }
70    }
71
72    public static int parameterizedHashCode(String value) {
73        return value.hashCode();
74    }
75
76    @Test
77    public void test2() {
78        ResolvedJavaMethod method = getResolvedJavaMethod("constantHashCode");
79        StructuredGraph graph = parseForCompile(method);
80
81        FixedNode firstFixed = graph.start().next();
82        Assert.assertThat(firstFixed, instanceOf(ReturnNode.class));
83
84        ReturnNode ret = (ReturnNode) firstFixed;
85        JavaConstant result = ret.result().asJavaConstant();
86        if (result == null) {
87            Assert.fail("result not constant: " + ret.result());
88        } else {
89            int expected = A_CONSTANT_STRING.hashCode();
90            Assert.assertEquals("result", expected, result.asInt());
91        }
92    }
93
94    public static int constantHashCode() {
95        return A_CONSTANT_STRING.hashCode();
96    }
97}
98