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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * 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
 * accompanied this code).
 *
 * 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,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
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package org.graalvm.compiler.lir.phases;

import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import java.util.ListIterator;

import org.graalvm.compiler.lir.gen.LIRGenerationResult;

import jdk.vm.ci.code.TargetDescription;

public class LIRPhaseSuite<C> extends LIRPhase<C> {
    private List<LIRPhase<C>> phases;
    private boolean immutable;

    public LIRPhaseSuite() {
        phases = new ArrayList<>();
    }

    /**
     * Add a new phase at the beginning of this suite.
     */
    public final void prependPhase(LIRPhase<C> phase) {
        phases.add(0, phase);
    }

    /**
     * Add a new phase at the end of this suite.
     */
    public final void appendPhase(LIRPhase<C> phase) {
        phases.add(phase);
    }

    public final ListIterator<LIRPhase<C>> findPhase(Class<? extends LIRPhase<C>> phaseClass) {
        ListIterator<LIRPhase<C>> it = phases.listIterator();
        if (findNextPhase(it, phaseClass)) {
            return it;
        } else {
            return null;
        }
    }

    public final <T extends LIRPhase<C>> T findPhaseInstance(Class<T> phaseClass) {
        ListIterator<LIRPhase<C>> it = phases.listIterator();
        while (it.hasNext()) {
            LIRPhase<C> phase = it.next();
            if (phaseClass.isInstance(phase)) {
                return phaseClass.cast(phase);
            }
        }
        return null;
    }

    public static <C> boolean findNextPhase(ListIterator<LIRPhase<C>> it, Class<? extends LIRPhase<C>> phaseClass) {
        while (it.hasNext()) {
            LIRPhase<C> phase = it.next();
            if (phaseClass.isInstance(phase)) {
                return true;
            }
        }
        return false;
    }

    @Override
    protected final void run(TargetDescription target, LIRGenerationResult lirGenRes, C context) {
        for (LIRPhase<C> phase : phases) {
            phase.apply(target, lirGenRes, context);
        }
    }

    public LIRPhaseSuite<C> copy() {
        LIRPhaseSuite<C> suite = new LIRPhaseSuite<>();
        suite.phases.addAll(phases);
        return suite;
    }

    public boolean isImmutable() {
        return immutable;
    }

    public synchronized void setImmutable() {
        if (!immutable) {
            phases = Collections.unmodifiableList(phases);
            immutable = true;
        }
    }
}