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23 
24 
25 package org.graalvm.compiler.phases.common;
26 
27 import java.util.Iterator;
28 import java.util.LinkedList;
29 import java.util.List;
30 
31 import org.graalvm.compiler.core.common.cfg.Loop;
32 import org.graalvm.compiler.core.common.type.StampFactory;
33 import org.graalvm.compiler.debug.DebugCloseable;
34 import org.graalvm.compiler.nodes.AbstractDeoptimizeNode;
35 import org.graalvm.compiler.nodes.AbstractMergeNode;
36 import org.graalvm.compiler.nodes.DynamicDeoptimizeNode;
37 import org.graalvm.compiler.nodes.EndNode;
38 import org.graalvm.compiler.nodes.FrameState;
39 import org.graalvm.compiler.nodes.LoopBeginNode;
40 import org.graalvm.compiler.nodes.LoopExitNode;
41 import org.graalvm.compiler.nodes.MergeNode;
42 import org.graalvm.compiler.nodes.PhiNode;
43 import org.graalvm.compiler.nodes.StructuredGraph;
44 import org.graalvm.compiler.nodes.ValueNode;
45 import org.graalvm.compiler.nodes.ValuePhiNode;
46 import org.graalvm.compiler.nodes.cfg.Block;
47 import org.graalvm.compiler.nodes.cfg.ControlFlowGraph;
48 import org.graalvm.compiler.phases.BasePhase;
49 import org.graalvm.compiler.phases.tiers.MidTierContext;
50 
51 /**
52  * This phase tries to find {@link AbstractDeoptimizeNode DeoptimizeNodes} which use the same
53  * {@link FrameState} and merges them together.
54  */
55 public class DeoptimizationGroupingPhase extends BasePhase<MidTierContext> {
56 
57     @Override
58     @SuppressWarnings("try")
run(StructuredGraph graph, MidTierContext context)59     protected void run(StructuredGraph graph, MidTierContext context) {
60         ControlFlowGraph cfg = null;
61         for (FrameState fs : graph.getNodes(FrameState.TYPE)) {
62             Iterator<AbstractDeoptimizeNode> iterator = fs.usages().filter(AbstractDeoptimizeNode.class).iterator();
63             if (!iterator.hasNext()) {
64                 // No deopt
65                 continue;
66             }
67             AbstractDeoptimizeNode first = iterator.next();
68             if (!iterator.hasNext()) {
69                 // Only 1 deopt
70                 continue;
71             }
72             // There is more than one deopt, create a merge
73             if (cfg == null) {
74                 cfg = ControlFlowGraph.compute(graph, true, true, false, false);
75             }
76             AbstractMergeNode merge = graph.add(new MergeNode());
77             EndNode firstEnd = graph.add(new EndNode());
78             ValueNode actionAndReason = first.getActionAndReason(context.getMetaAccess());
79             ValueNode speculation = first.getSpeculation(context.getMetaAccess());
80             PhiNode reasonActionPhi = graph.addWithoutUnique(new ValuePhiNode(StampFactory.forKind(actionAndReason.getStackKind()), merge));
81             PhiNode speculationPhi = graph.addWithoutUnique(new ValuePhiNode(StampFactory.forKind(speculation.getStackKind()), merge));
82             merge.addForwardEnd(firstEnd);
83             reasonActionPhi.addInput(actionAndReason);
84             speculationPhi.addInput(speculation);
85             first.replaceAtPredecessor(firstEnd);
86             exitLoops(first, firstEnd, cfg);
87             DynamicDeoptimizeNode dynamicDeopt;
88             try (DebugCloseable position = first.withNodeSourcePosition()) {
89                 dynamicDeopt = new DynamicDeoptimizeNode(reasonActionPhi, speculationPhi);
90                 merge.setNext(graph.add(dynamicDeopt));
91             }
92             List<AbstractDeoptimizeNode> obsoletes = new LinkedList<>();
93             obsoletes.add(first);
94 
95             do {
96                 AbstractDeoptimizeNode deopt = iterator.next();
97                 EndNode newEnd = graph.add(new EndNode());
98                 merge.addForwardEnd(newEnd);
99                 reasonActionPhi.addInput(deopt.getActionAndReason(context.getMetaAccess()));
100                 speculationPhi.addInput(deopt.getSpeculation(context.getMetaAccess()));
101                 deopt.replaceAtPredecessor(newEnd);
102                 exitLoops(deopt, newEnd, cfg);
103                 obsoletes.add(deopt);
104             } while (iterator.hasNext());
105 
106             dynamicDeopt.setStateBefore(fs);
107             for (AbstractDeoptimizeNode obsolete : obsoletes) {
108                 obsolete.safeDelete();
109             }
110         }
111     }
112 
exitLoops(AbstractDeoptimizeNode deopt, EndNode end, ControlFlowGraph cfg)113     private static void exitLoops(AbstractDeoptimizeNode deopt, EndNode end, ControlFlowGraph cfg) {
114         Block block = cfg.blockFor(deopt);
115         Loop<Block> loop = block.getLoop();
116         while (loop != null) {
117             end.graph().addBeforeFixed(end, end.graph().add(new LoopExitNode((LoopBeginNode) loop.getHeader().getBeginNode())));
118             loop = loop.getParent();
119         }
120     }
121 
122     @Override
codeSizeIncrease()123     public float codeSizeIncrease() {
124         return 2.5f;
125     }
126 }
127