1 /*
   2  * Copyright (c) 2009, 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  */
  23 package org.graalvm.compiler.nodes.java;
  24 
  25 import static org.graalvm.compiler.nodeinfo.InputType.Memory;
  26 import static org.graalvm.compiler.nodeinfo.NodeCycles.CYCLES_10;
  27 import static org.graalvm.compiler.nodeinfo.NodeSize.SIZE_8;
  28 
  29 import org.graalvm.compiler.core.common.LocationIdentity;
  30 import org.graalvm.compiler.core.common.type.StampFactory;
  31 import org.graalvm.compiler.core.common.type.TypeReference;
  32 import org.graalvm.compiler.graph.NodeClass;
  33 import org.graalvm.compiler.nodeinfo.InputType;
  34 import org.graalvm.compiler.nodeinfo.NodeInfo;
  35 import org.graalvm.compiler.nodes.AbstractBeginNode;
  36 import org.graalvm.compiler.nodes.BeginStateSplitNode;
  37 import org.graalvm.compiler.nodes.InvokeWithExceptionNode;
  38 import org.graalvm.compiler.nodes.KillingBeginNode;
  39 import org.graalvm.compiler.nodes.StructuredGraph;
  40 import org.graalvm.compiler.nodes.memory.MemoryCheckpoint;
  41 import org.graalvm.compiler.nodes.spi.Lowerable;
  42 import org.graalvm.compiler.nodes.spi.LoweringTool;
  43 
  44 import jdk.vm.ci.meta.MetaAccessProvider;
  45 
  46 /**
  47  * The entry to an exception handler with the exception coming from a call (as opposed to a local
  48  * throw instruction or implicit exception).
  49  */
  50 @NodeInfo(allowedUsageTypes = Memory, cycles = CYCLES_10, size = SIZE_8)
  51 public final class ExceptionObjectNode extends BeginStateSplitNode implements Lowerable, MemoryCheckpoint.Single {
  52     public static final NodeClass<ExceptionObjectNode> TYPE = NodeClass.create(ExceptionObjectNode.class);
  53 
  54     public ExceptionObjectNode(MetaAccessProvider metaAccess) {
  55         super(TYPE, StampFactory.objectNonNull(TypeReference.createTrustedWithoutAssumptions(metaAccess.lookupJavaType(Throwable.class))));
  56     }
  57 
  58     @Override
  59     public LocationIdentity getLocationIdentity() {
  60         return LocationIdentity.any();
  61     }
  62 
  63     @Override
  64     public void lower(LoweringTool tool) {
  65         if (graph().getGuardsStage() == StructuredGraph.GuardsStage.FIXED_DEOPTS) {
  66             /*
  67              * Now the lowering to BeginNode+LoadExceptionNode can be performed, since no more
  68              * deopts can float in between the begin node and the load exception node.
  69              */
  70             LocationIdentity locationsKilledByInvoke = ((InvokeWithExceptionNode) predecessor()).getLocationIdentity();
  71             AbstractBeginNode entry = graph().add(KillingBeginNode.create(locationsKilledByInvoke));
  72             LoadExceptionObjectNode loadException = graph().add(new LoadExceptionObjectNode(stamp()));
  73 
  74             loadException.setStateAfter(stateAfter());
  75             replaceAtUsages(InputType.Value, loadException);
  76             graph().replaceFixedWithFixed(this, entry);
  77             entry.graph().addAfterFixed(entry, loadException);
  78 
  79             loadException.lower(tool);
  80         }
  81     }
  82 
  83     @Override
  84     public boolean verify() {
  85         assertTrue(stateAfter() != null, "an exception handler needs a frame state");
  86         return super.verify();
  87     }
  88 }