1 /*
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13  * accompanied this code).
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23 
24 
25 package org.graalvm.compiler.nodes;
26 
27 import org.graalvm.compiler.graph.Node;
28 import org.graalvm.compiler.graph.NodeClass;
29 import org.graalvm.compiler.graph.spi.Canonicalizable;
30 import org.graalvm.compiler.graph.spi.CanonicalizerTool;
31 import org.graalvm.compiler.nodeinfo.NodeInfo;
32 import org.graalvm.compiler.nodes.extended.GuardingNode;
33 import org.graalvm.compiler.nodes.spi.ValueProxy;
34 import org.graalvm.compiler.nodes.spi.Virtualizable;
35 import org.graalvm.compiler.nodes.spi.VirtualizerTool;
36 import org.graalvm.compiler.nodes.virtual.VirtualObjectNode;
37 
38 @NodeInfo(nameTemplate = "ValueProxy({i#value})")
39 public final class ValueProxyNode extends ProxyNode implements Canonicalizable, Virtualizable, ValueProxy {
40 
41     public static final NodeClass<ValueProxyNode> TYPE = NodeClass.create(ValueProxyNode.class);
42     @Input ValueNode value;
43     private final boolean loopPhiProxy;
44 
ValueProxyNode(ValueNode value, LoopExitNode loopExit)45     public ValueProxyNode(ValueNode value, LoopExitNode loopExit) {
46         super(TYPE, value.stamp(NodeView.DEFAULT), loopExit);
47         this.value = value;
48         loopPhiProxy = loopExit.loopBegin().isPhiAtMerge(value);
49     }
50 
51     @Override
value()52     public ValueNode value() {
53         return value;
54     }
55 
56     @Override
createPhi(AbstractMergeNode merge)57     public PhiNode createPhi(AbstractMergeNode merge) {
58         return graph().addWithoutUnique(new ValuePhiNode(stamp(NodeView.DEFAULT), merge));
59     }
60 
61     @Override
inferStamp()62     public boolean inferStamp() {
63         return updateStamp(value.stamp(NodeView.DEFAULT));
64     }
65 
66     @Override
canonical(CanonicalizerTool tool)67     public Node canonical(CanonicalizerTool tool) {
68         Node result = super.canonical(tool);
69         if (result != this) {
70             return result;
71         }
72 
73         ValueNode curValue = value;
74         if (curValue.getNodeClass().isLeafNode()) {
75             return curValue;
76         }
77         if (loopPhiProxy && !loopExit.loopBegin().isPhiAtMerge(curValue)) {
78             return curValue;
79         }
80         return this;
81     }
82 
83     @Override
virtualize(VirtualizerTool tool)84     public void virtualize(VirtualizerTool tool) {
85         ValueNode alias = tool.getAlias(value);
86         if (alias instanceof VirtualObjectNode) {
87             tool.replaceWithVirtual((VirtualObjectNode) alias);
88         }
89     }
90 
91     @Override
getOriginalNode()92     public ValueNode getOriginalNode() {
93         return value();
94     }
95 
96     @Override
getGuard()97     public GuardingNode getGuard() {
98         return this.proxyPoint();
99     }
100 }
101