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 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
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 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
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package org.graalvm.compiler.phases.common.instrumentation;

import static org.graalvm.compiler.core.common.CompilationIdentifier.INVALID_COMPILATION_ID;

import java.util.Collections;
import java.util.Map;

import org.graalvm.compiler.core.common.type.StampPair;
import org.graalvm.compiler.debug.Debug;
import org.graalvm.compiler.debug.GraalError;
import org.graalvm.compiler.graph.Node;
import org.graalvm.compiler.graph.NodeBitMap;
import org.graalvm.compiler.graph.NodeFlood;
import org.graalvm.compiler.graph.Position;
import org.graalvm.compiler.nodeinfo.InputType;
import org.graalvm.compiler.nodes.AbstractEndNode;
import org.graalvm.compiler.nodes.AbstractLocalNode;
import org.graalvm.compiler.nodes.FixedNode;
import org.graalvm.compiler.nodes.FrameState;
import org.graalvm.compiler.nodes.LoopEndNode;
import org.graalvm.compiler.nodes.ParameterNode;
import org.graalvm.compiler.nodes.ReturnNode;
import org.graalvm.compiler.nodes.StructuredGraph;
import org.graalvm.compiler.nodes.StructuredGraph.AllowAssumptions;
import org.graalvm.compiler.nodes.ValueNode;
import org.graalvm.compiler.nodes.calc.FloatingNode;
import org.graalvm.compiler.nodes.debug.instrumentation.InstrumentationBeginNode;
import org.graalvm.compiler.nodes.debug.instrumentation.InstrumentationEndNode;
import org.graalvm.compiler.nodes.debug.instrumentation.InstrumentationNode;
import org.graalvm.compiler.nodes.util.GraphUtil;
import org.graalvm.compiler.nodes.virtual.EscapeObjectState;
import org.graalvm.compiler.phases.BasePhase;
import org.graalvm.compiler.phases.common.DeadCodeEliminationPhase;
import org.graalvm.compiler.phases.tiers.HighTierContext;

The ExtractInstrumentationPhase extracts the instrumentation (whose boundary are indicated by instrumentationBegin and instrumentationEnd), and insert an InstrumentationNode in the graph to take place of the instrumentation.
/** * The {@code ExtractInstrumentationPhase} extracts the instrumentation (whose boundary are * indicated by instrumentationBegin and instrumentationEnd), and insert an * {@link InstrumentationNode} in the graph to take place of the instrumentation. */
public class ExtractInstrumentationPhase extends BasePhase<HighTierContext> { @Override protected void run(StructuredGraph graph, HighTierContext context) { for (InstrumentationBeginNode begin : graph.getNodes().filter(InstrumentationBeginNode.class)) { Instrumentation instrumentation = new Instrumentation(begin); if (begin.isAnchored() || begin.getTarget() != null) { // we create InstrumentationNode when the instrumentation is anchored (when 0 is // passed to instrumentationBegin), or when the instrumentation is associated with // some target. InstrumentationNode instrumentationNode = graph.addWithoutUnique(new InstrumentationNode(begin.getTarget(), begin.isAnchored())); graph.addBeforeFixed(begin, instrumentationNode); FrameState currentState = begin.stateAfter(); FrameState newState = graph.addWithoutUnique(new FrameState(currentState.outerFrameState(), currentState.getCode(), currentState.bci, 0, 0, 0, currentState.rethrowException(), currentState.duringCall(), null, Collections.<EscapeObjectState> emptyList())); instrumentationNode.setStateBefore(newState); StructuredGraph instrumentationGraph = instrumentation.genInstrumentationGraph(graph, instrumentationNode); new DeadCodeEliminationPhase().apply(instrumentationGraph, false); instrumentationNode.setInstrumentationGraph(instrumentationGraph); Debug.dump(Debug.INFO_LOG_LEVEL, instrumentationGraph, "After extracted instrumentation at %s", instrumentation); } instrumentation.unlink(); } }
This class denotes the instrumentation code being detached from the graph.
/** * This class denotes the instrumentation code being detached from the graph. */
private static class Instrumentation { private InstrumentationBeginNode begin; private InstrumentationEndNode end; private NodeBitMap nodes; Instrumentation(InstrumentationBeginNode begin) { this.begin = begin; // travel along the control flow for the paired InstrumentationEndNode NodeFlood cfgFlood = begin.graph().createNodeFlood(); cfgFlood.add(begin.next()); for (Node current : cfgFlood) { if (current instanceof InstrumentationEndNode) { this.end = (InstrumentationEndNode) current; } else if (current instanceof LoopEndNode) { // do nothing } else if (current instanceof AbstractEndNode) { cfgFlood.add(((AbstractEndNode) current).merge()); } else { cfgFlood.addAll(current.successors()); } } if (this.end == null) { // this may be caused by DeoptimizationReason.Unresolved throw GraalError.shouldNotReachHere("could not find invocation to instrumentationEnd()"); } // all FloatingNodes (except AbstractLocalNodes), which the FixedNodes in the // instrumentation depend on, are included in the instrumentation if they are not used // by other nodes in the graph NodeBitMap cfgNodes = cfgFlood.getVisited(); NodeFlood dfgFlood = begin.graph().createNodeFlood(); dfgFlood.addAll(cfgNodes); dfgFlood.add(begin.stateAfter()); for (Node current : dfgFlood) { for (Position pos : current.inputPositions()) { Node input = pos.get(current); if (pos.getInputType() == InputType.Value) { if (current instanceof FrameState) { // don't include value input for the FrameState continue; } if (!(input instanceof FloatingNode)) { // we only consider FloatingNode for this input type continue; } if (input instanceof AbstractLocalNode) { // AbstractLocalNode is invalid in the instrumentation sub-graph continue; } if (shouldIncludeValueInput((FloatingNode) input, cfgNodes)) { dfgFlood.add(input); } } else { dfgFlood.add(input); } } } this.nodes = dfgFlood.getVisited(); }
Copy the instrumentation nodes into a separate graph. During the copying, this method updates the input of the given InstrumentationNode. Hence, it is essential that the given InstrumentationNode is alive.
/** * Copy the instrumentation nodes into a separate graph. During the copying, this method * updates the input of the given InstrumentationNode. Hence, it is essential that the given * InstrumentationNode is alive. */
StructuredGraph genInstrumentationGraph(StructuredGraph oldGraph, InstrumentationNode instrumentationNode) { StructuredGraph instrumentationGraph = new StructuredGraph(AllowAssumptions.YES, INVALID_COMPILATION_ID); Map<Node, Node> replacements = Node.newMap(); int index = 0; // for ParameterNode index for (Node current : nodes) { // mark any input that is not included in the instrumentation a weak dependency for (Node input : current.inputs()) { if (input instanceof ValueNode) { ValueNode valueNode = (ValueNode) input; if (!nodes.isMarked(input) && !replacements.containsKey(input)) { // create a ParameterNode in case the input is not within the // instrumentation ParameterNode parameter = new ParameterNode(index++, StampPair.createSingle(valueNode.stamp())); instrumentationGraph.addWithoutUnique(parameter); instrumentationNode.addWeakDependency(valueNode); replacements.put(input, parameter); } } } } replacements = instrumentationGraph.addDuplicates(nodes, oldGraph, nodes.count(), replacements); instrumentationGraph.start().setNext((FixedNode) replacements.get(begin.next())); instrumentationGraph.start().setStateAfter((FrameState) replacements.get(begin.stateAfter())); replacements.get(end).replaceAtPredecessor(instrumentationGraph.addWithoutUnique(new ReturnNode(null))); return instrumentationGraph; }
Returns:true if the given FloatingNode does not contain any FixedNode input of types other than InputType.Value.
/** * @return true if the given FloatingNode does not contain any FixedNode input of types * other than InputType.Value. */
private static boolean shouldIncludeValueInput(FloatingNode node, NodeBitMap cfgNodes) { for (Position pos : node.inputPositions()) { if (pos.getInputType() == InputType.Value) { continue; } Node input = pos.get(node); if (input instanceof FixedNode && !cfgNodes.isMarked(input)) { return false; } } return true; } void unlink() { FixedNode next = end.next(); end.setNext(null); begin.replaceAtPredecessor(next); GraphUtil.killCFG(begin); } } @Override public boolean checkContract() { return false; } }