1 /* 2 * Copyright (c) 2012, 2020, 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 24 25 package org.graalvm.compiler.hotspot.replacements; 26 27 import static org.graalvm.compiler.hotspot.meta.HotSpotForeignCallsProviderImpl.LOAD_AND_CLEAR_EXCEPTION; 28 import static org.graalvm.compiler.hotspot.replacements.HotSpotReplacementsUtil.EXCEPTION_OOP_LOCATION; 29 import static org.graalvm.compiler.hotspot.replacements.HotSpotReplacementsUtil.EXCEPTION_PC_LOCATION; 30 import static org.graalvm.compiler.hotspot.replacements.HotSpotReplacementsUtil.readExceptionOop; 31 import static org.graalvm.compiler.hotspot.replacements.HotSpotReplacementsUtil.registerAsWord; 32 import static org.graalvm.compiler.hotspot.replacements.HotSpotReplacementsUtil.writeExceptionOop; 33 import static org.graalvm.compiler.hotspot.replacements.HotSpotReplacementsUtil.writeExceptionPc; 34 import static org.graalvm.compiler.hotspot.replacements.HotspotSnippetsOptions.LoadExceptionObjectInVM; 35 import static org.graalvm.compiler.nodes.PiNode.piCastToSnippetReplaceeStamp; 36 import static org.graalvm.compiler.replacements.SnippetTemplate.DEFAULT_REPLACER; 37 38 import org.graalvm.compiler.api.replacements.Snippet; 39 import org.graalvm.compiler.api.replacements.Snippet.ConstantParameter; 40 import org.graalvm.compiler.core.common.type.Stamp; 41 import org.graalvm.compiler.debug.DebugHandlersFactory; 42 import org.graalvm.compiler.hotspot.meta.HotSpotProviders; 43 import org.graalvm.compiler.hotspot.meta.HotSpotRegistersProvider; 44 import org.graalvm.compiler.hotspot.word.HotSpotWordTypes; 45 import org.graalvm.compiler.nodes.StructuredGraph; 46 import org.graalvm.compiler.nodes.extended.ForeignCallNode; 47 import org.graalvm.compiler.nodes.java.LoadExceptionObjectNode; 48 import org.graalvm.compiler.nodes.spi.LoweringTool; 49 import org.graalvm.compiler.options.OptionValues; 50 import org.graalvm.compiler.replacements.SnippetTemplate.AbstractTemplates; 51 import org.graalvm.compiler.replacements.SnippetTemplate.Arguments; 52 import org.graalvm.compiler.replacements.SnippetTemplate.SnippetInfo; 53 import org.graalvm.compiler.replacements.Snippets; 54 import org.graalvm.compiler.replacements.nodes.ReadRegisterNode; 55 import org.graalvm.compiler.word.Word; 56 import jdk.internal.vm.compiler.word.WordFactory; 57 58 import jdk.vm.ci.code.BytecodeFrame; 59 import jdk.vm.ci.code.Register; 60 import jdk.vm.ci.code.TargetDescription; 61 import jdk.vm.ci.meta.ResolvedJavaType; 62 63 /** 64 * Snippet for loading the exception object at the start of an exception dispatcher. 65 * <p> 66 * The frame state upon entry to an exception handler is such that it is a 67 * {@link BytecodeFrame#rethrowException rethrow exception} state and the stack contains exactly the 68 * exception object (per the JVM spec) to rethrow. This means that the code generated for this node 69 * must not cause a deoptimization as the runtime/interpreter would not have a valid location to 70 * find the exception object to be rethrown. 71 */ 72 public class LoadExceptionObjectSnippets implements Snippets { 73 74 @Snippet loadException(@onstantParameter Register threadRegister)75 public static Object loadException(@ConstantParameter Register threadRegister) { 76 Word thread = registerAsWord(threadRegister); 77 Object exception = readExceptionOop(thread); 78 writeExceptionOop(thread, null); 79 writeExceptionPc(thread, WordFactory.zero()); 80 return piCastToSnippetReplaceeStamp(exception); 81 } 82 83 public static class Templates extends AbstractTemplates { 84 85 private final SnippetInfo loadException = snippet(LoadExceptionObjectSnippets.class, "loadException", EXCEPTION_OOP_LOCATION, EXCEPTION_PC_LOCATION); 86 private final HotSpotWordTypes wordTypes; 87 Templates(OptionValues options, Iterable<DebugHandlersFactory> factories, HotSpotProviders providers, TargetDescription target)88 public Templates(OptionValues options, Iterable<DebugHandlersFactory> factories, HotSpotProviders providers, TargetDescription target) { 89 super(options, factories, providers, providers.getSnippetReflection(), target); 90 this.wordTypes = providers.getWordTypes(); 91 } 92 lower(LoadExceptionObjectNode loadExceptionObject, HotSpotRegistersProvider registers, LoweringTool tool)93 public void lower(LoadExceptionObjectNode loadExceptionObject, HotSpotRegistersProvider registers, LoweringTool tool) { 94 StructuredGraph graph = loadExceptionObject.graph(); 95 if (LoadExceptionObjectInVM.getValue(graph.getOptions())) { 96 ResolvedJavaType wordType = providers.getMetaAccess().lookupJavaType(Word.class); 97 Stamp stamp = wordTypes.getWordStamp(wordType); 98 ReadRegisterNode thread = graph.add(new ReadRegisterNode(stamp, registers.getThreadRegister(), true, false)); 99 graph.addBeforeFixed(loadExceptionObject, thread); 100 ForeignCallNode loadExceptionC = graph.add(new ForeignCallNode(LOAD_AND_CLEAR_EXCEPTION, thread)); 101 loadExceptionC.setStateAfter(loadExceptionObject.stateAfter()); 102 graph.replaceFixedWithFixed(loadExceptionObject, loadExceptionC); 103 } else { 104 Arguments args = new Arguments(loadException, loadExceptionObject.graph().getGuardsStage(), tool.getLoweringStage()); 105 args.addConst("threadRegister", registers.getThreadRegister()); 106 template(loadExceptionObject, args).instantiate(providers.getMetaAccess(), loadExceptionObject, DEFAULT_REPLACER, args); 107 } 108 } 109 } 110 } 111