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.stubs;
24
25 import static org.graalvm.compiler.hotspot.nodes.JumpToExceptionHandlerInCallerNode.jumpToExceptionHandlerInCaller;
26 import static org.graalvm.compiler.hotspot.replacements.HotSpotReplacementsUtil.registerAsWord;
27 import static org.graalvm.compiler.hotspot.stubs.ExceptionHandlerStub.checkExceptionNotNull;
28 import static org.graalvm.compiler.hotspot.stubs.ExceptionHandlerStub.checkNoExceptionInThread;
29 import static org.graalvm.compiler.hotspot.stubs.StubUtil.cAssertionsEnabled;
30 import static org.graalvm.compiler.hotspot.stubs.StubUtil.decipher;
31 import static org.graalvm.compiler.hotspot.stubs.StubUtil.newDescriptor;
32 import static org.graalvm.compiler.hotspot.stubs.StubUtil.printf;
33
34 import org.graalvm.compiler.api.replacements.Fold;
35 import org.graalvm.compiler.api.replacements.Fold.InjectedParameter;
36 import org.graalvm.compiler.api.replacements.Snippet;
37 import org.graalvm.compiler.api.replacements.Snippet.ConstantParameter;
38 import org.graalvm.compiler.core.common.spi.ForeignCallDescriptor;
39 import org.graalvm.compiler.graph.Node.ConstantNodeParameter;
40 import org.graalvm.compiler.graph.Node.NodeIntrinsic;
41 import org.graalvm.compiler.hotspot.GraalHotSpotVMConfig;
42 import org.graalvm.compiler.hotspot.HotSpotForeignCallLinkage;
43 import org.graalvm.compiler.hotspot.meta.HotSpotProviders;
44 import org.graalvm.compiler.hotspot.nodes.StubForeignCallNode;
45 import org.graalvm.compiler.nodes.UnwindNode;
46 import org.graalvm.compiler.word.Pointer;
47 import org.graalvm.compiler.word.Word;
48
49 import jdk.vm.ci.code.Register;
50
51 /**
52 * Stub called by an {@link UnwindNode}. This stub executes in the frame of the method throwing an
53 * exception and completes by jumping to the exception handler in the calling frame.
54 */
55 public class UnwindExceptionToCallerStub extends SnippetStub {
56
57 public UnwindExceptionToCallerStub(HotSpotProviders providers, HotSpotForeignCallLinkage linkage) {
58 super("unwindExceptionToCaller", providers, linkage);
59 }
60
61 /**
62 * The current frame is unwound by this stub. Therefore, it does not need to save any registers
63 * as HotSpot uses a caller save convention.
64 */
65 @Override
66 public boolean preservesRegisters() {
67 return false;
68 }
69
70 @Override
71 protected Object getConstantParameterValue(int index, String name) {
72 assert index == 2;
73 return providers.getRegisters().getThreadRegister();
74 }
75
76 @Snippet
77 private static void unwindExceptionToCaller(Object exception, Word returnAddress, @ConstantParameter Register threadRegister) {
78 Pointer exceptionOop = Word.objectToTrackedPointer(exception);
79 if (logging()) {
80 printf("unwinding exception %p (", exceptionOop.rawValue());
81 decipher(exceptionOop.rawValue());
82 printf(") at %p (", returnAddress.rawValue());
83 decipher(returnAddress.rawValue());
84 printf(")\n");
85 }
86 Word thread = registerAsWord(threadRegister);
87 checkNoExceptionInThread(thread, assertionsEnabled(null));
88 checkExceptionNotNull(assertionsEnabled(null), exception);
89
90 Word handlerInCallerPc = exceptionHandlerForReturnAddress(EXCEPTION_HANDLER_FOR_RETURN_ADDRESS, thread, returnAddress);
91
92 if (logging()) {
93 printf("handler for exception %p at return address %p is at %p (", exceptionOop.rawValue(), returnAddress.rawValue(), handlerInCallerPc.rawValue());
94 decipher(handlerInCallerPc.rawValue());
95 printf(")\n");
96 }
97
98 jumpToExceptionHandlerInCaller(handlerInCallerPc, exception, returnAddress);
99 }
100
101 @Fold
102 static boolean logging() {
103 return StubOptions.TraceUnwindStub.getValue();
104 }
105
106 /**
107 * Determines if either Java assertions are enabled for {@link UnwindExceptionToCallerStub} or
108 * if this is a HotSpot build where the ASSERT mechanism is enabled.
109 * <p>
110 * This first check relies on the per-class assertion status which is why this method must be in
111 * this class.
112 */
113 @Fold
114 @SuppressWarnings("all")
115 static boolean assertionsEnabled(@InjectedParameter GraalHotSpotVMConfig config) {
116 boolean enabled = false;
117 assert enabled = true;
118 return enabled || cAssertionsEnabled(config);
119 }
120
121 public static final ForeignCallDescriptor EXCEPTION_HANDLER_FOR_RETURN_ADDRESS = newDescriptor(UnwindExceptionToCallerStub.class, "exceptionHandlerForReturnAddress", Word.class, Word.class,
122 Word.class);
123
124 @NodeIntrinsic(value = StubForeignCallNode.class, setStampFromReturnType = true)
125 public static native Word exceptionHandlerForReturnAddress(@ConstantNodeParameter ForeignCallDescriptor exceptionHandlerForReturnAddress, Word thread, Word returnAddress);
126 }