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package org.graalvm.compiler.graph;

An entity that depends upon stable node identifiers.
/** * An entity that depends upon {@linkplain Graph#maybeCompress() stable} node identifiers. */
class NodeIdAccessor { final Graph graph; final int epoch; NodeIdAccessor(Graph graph) { this.graph = graph; this.epoch = graph.compressions; } Graph getGraph() { return graph; }
Verifies that node identifiers have not changed since this object was created.
Throws:
Returns:true if the check succeeds
/** * Verifies that node identifiers have not changed since this object was created. * * @return true if the check succeeds * @throws VerificationError if the check fails */
boolean verifyIdsAreStable() { int compressions = graph.compressions - epoch; if (compressions != 0) { throw new VerificationError("accessing node id in %s across %d graph compression%s", graph, compressions, compressions == 1 ? "" : "s"); } return true; }
Gets the identifier for a node. If assertions are enabled, this method asserts that the identifier is stable.
/** * Gets the identifier for a node. If assertions are enabled, this method asserts that the * identifier is stable. */
int getNodeId(Node node) { assert verifyIdsAreStable(); return node.id(); } }