1 /*
2 * Copyright (c) 2012, 2015, 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 */
23 package org.graalvm.compiler.hotspot.replacements;
24
25 import static org.graalvm.compiler.hotspot.meta.HotSpotForeignCallsProviderImpl.LOAD_AND_CLEAR_EXCEPTION;
26 import static org.graalvm.compiler.hotspot.replacements.HotSpotReplacementsUtil.EXCEPTION_OOP_LOCATION;
27 import static org.graalvm.compiler.hotspot.replacements.HotSpotReplacementsUtil.EXCEPTION_PC_LOCATION;
28 import static org.graalvm.compiler.hotspot.replacements.HotSpotReplacementsUtil.readExceptionOop;
29 import static org.graalvm.compiler.hotspot.replacements.HotSpotReplacementsUtil.registerAsWord;
30 import static org.graalvm.compiler.hotspot.replacements.HotSpotReplacementsUtil.writeExceptionOop;
31 import static org.graalvm.compiler.hotspot.replacements.HotSpotReplacementsUtil.writeExceptionPc;
32 import static org.graalvm.compiler.hotspot.replacements.HotspotSnippetsOptions.LoadExceptionObjectInVM;
33 import static org.graalvm.compiler.nodes.PiNode.piCastToSnippetReplaceeStamp;
34 import static org.graalvm.compiler.replacements.SnippetTemplate.DEFAULT_REPLACER;
35
36 import org.graalvm.compiler.api.replacements.Snippet;
37 import org.graalvm.compiler.api.replacements.Snippet.ConstantParameter;
38 import org.graalvm.compiler.core.common.type.Stamp;
39 import org.graalvm.compiler.hotspot.meta.HotSpotProviders;
40 import org.graalvm.compiler.hotspot.meta.HotSpotRegistersProvider;
41 import org.graalvm.compiler.hotspot.word.HotSpotWordTypes;
42 import org.graalvm.compiler.nodes.StructuredGraph;
43 import org.graalvm.compiler.nodes.extended.ForeignCallNode;
44 import org.graalvm.compiler.nodes.java.LoadExceptionObjectNode;
45 import org.graalvm.compiler.nodes.spi.LoweringTool;
46 import org.graalvm.compiler.options.OptionValues;
47 import org.graalvm.compiler.replacements.SnippetTemplate.AbstractTemplates;
48 import org.graalvm.compiler.replacements.SnippetTemplate.Arguments;
49 import org.graalvm.compiler.replacements.SnippetTemplate.SnippetInfo;
50 import org.graalvm.compiler.replacements.Snippets;
51 import org.graalvm.compiler.replacements.nodes.ReadRegisterNode;
52 import org.graalvm.compiler.word.Word;
53 import org.graalvm.word.WordFactory;
54
55 import jdk.vm.ci.code.BytecodeFrame;
56 import jdk.vm.ci.code.Register;
57 import jdk.vm.ci.code.TargetDescription;
58 import jdk.vm.ci.meta.ResolvedJavaType;
59
60 /**
61 * Snippet for loading the exception object at the start of an exception dispatcher.
62 * <p>
63 * The frame state upon entry to an exception handler is such that it is a
64 * {@link BytecodeFrame#rethrowException rethrow exception} state and the stack contains exactly the
65 * exception object (per the JVM spec) to rethrow. This means that the code generated for this node
66 * must not cause a deoptimization as the runtime/interpreter would not have a valid location to
67 * find the exception object to be rethrown.
68 */
69 public class LoadExceptionObjectSnippets implements Snippets {
70
71 @Snippet
72 public static Object loadException(@ConstantParameter Register threadRegister) {
73 Word thread = registerAsWord(threadRegister);
74 Object exception = readExceptionOop(thread);
75 writeExceptionOop(thread, null);
76 writeExceptionPc(thread, WordFactory.zero());
77 return piCastToSnippetReplaceeStamp(exception);
78 }
79
80 public static class Templates extends AbstractTemplates {
81
82 private final SnippetInfo loadException = snippet(LoadExceptionObjectSnippets.class, "loadException", EXCEPTION_OOP_LOCATION, EXCEPTION_PC_LOCATION);
83 private final HotSpotWordTypes wordTypes;
84
85 public Templates(OptionValues options, HotSpotProviders providers, TargetDescription target) {
86 super(options, providers, providers.getSnippetReflection(), target);
87 this.wordTypes = providers.getWordTypes();
88 }
89
90 public void lower(LoadExceptionObjectNode loadExceptionObject, HotSpotRegistersProvider registers, LoweringTool tool) {
91 StructuredGraph graph = loadExceptionObject.graph();
92 if (LoadExceptionObjectInVM.getValue(graph.getOptions())) {
93 ResolvedJavaType wordType = providers.getMetaAccess().lookupJavaType(Word.class);
94 Stamp stamp = wordTypes.getWordStamp(wordType);
95 ReadRegisterNode thread = graph.add(new ReadRegisterNode(stamp, registers.getThreadRegister(), true, false));
96 graph.addBeforeFixed(loadExceptionObject, thread);
97 ForeignCallNode loadExceptionC = graph.add(new ForeignCallNode(providers.getForeignCalls(), LOAD_AND_CLEAR_EXCEPTION, thread));
98 loadExceptionC.setStateAfter(loadExceptionObject.stateAfter());
99 graph.replaceFixedWithFixed(loadExceptionObject, loadExceptionC);
100 } else {
101 Arguments args = new Arguments(loadException, loadExceptionObject.graph().getGuardsStage(), tool.getLoweringStage());
102 args.addConst("threadRegister", registers.getThreadRegister());
103 template(args).instantiate(providers.getMetaAccess(), loadExceptionObject, DEFAULT_REPLACER, args);
104 }
105 }
106 }
107 }