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package org.graalvm.compiler.graph;

import java.util.function.Consumer;

import jdk.internal.vm.compiler.collections.UnmodifiableEconomicMap;

This class is a container of a graph that needs to be readonly and optionally a lazily created mutable copy of the graph.
/** * This class is a container of a graph that needs to be readonly and optionally a lazily created * mutable copy of the graph. */
public final class CachedGraph<G extends Graph> { private final G readonlyCopy; private G mutableCopy; private CachedGraph(G readonlyCopy, G mutableCopy) { this.readonlyCopy = readonlyCopy; this.mutableCopy = mutableCopy; } public static <G extends Graph> CachedGraph<G> fromReadonlyCopy(G graph) { return new CachedGraph<>(graph, null); } public static <G extends Graph> CachedGraph<G> fromMutableCopy(G graph) { return new CachedGraph<>(graph, graph); } public G getReadonlyCopy() { if (hasMutableCopy()) { return mutableCopy; } return readonlyCopy; } public boolean hasMutableCopy() { return mutableCopy != null; } @SuppressWarnings("unchecked") public G getMutableCopy(Consumer<UnmodifiableEconomicMap<Node, Node>> duplicationMapCallback) { if (!hasMutableCopy()) { // Sharing the debug context with the copy is safe since both graphs are // only used in the current thread. mutableCopy = (G) readonlyCopy.copy(duplicationMapCallback, readonlyCopy.getDebug()); } return mutableCopy; } }