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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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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
 * accompanied this code).
 *
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 * 2 along with this work; if not, write to the Free Software Foundation,
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package org.graalvm.compiler.loop.phases;

import org.graalvm.compiler.debug.CounterKey;
import org.graalvm.compiler.debug.DebugContext;
import org.graalvm.compiler.loop.LoopEx;
import org.graalvm.compiler.loop.LoopPolicies;
import org.graalvm.compiler.loop.LoopsData;
import org.graalvm.compiler.nodes.StructuredGraph;
import org.graalvm.compiler.phases.common.CanonicalizerPhase;
import org.graalvm.compiler.phases.tiers.PhaseContext;

public class LoopFullUnrollPhase extends LoopPhase<LoopPolicies> {

    private static final CounterKey FULLY_UNROLLED_LOOPS = DebugContext.counter("FullUnrolls");
    private final CanonicalizerPhase canonicalizer;

    public LoopFullUnrollPhase(CanonicalizerPhase canonicalizer, LoopPolicies policies) {
        super(policies);
        this.canonicalizer = canonicalizer;
    }

    @Override
    protected void run(StructuredGraph graph, PhaseContext context) {
        DebugContext debug = graph.getDebug();
        if (graph.hasLoops()) {
            boolean peeled;
            do {
                peeled = false;
                final LoopsData dataCounted = new LoopsData(graph);
                dataCounted.detectedCountedLoops();
                for (LoopEx loop : dataCounted.countedLoops()) {
                    if (getPolicies().shouldFullUnroll(loop)) {
                        debug.log("FullUnroll %s", loop);
                        LoopTransformations.fullUnroll(loop, context, canonicalizer);
                        FULLY_UNROLLED_LOOPS.increment(debug);
                        debug.dump(DebugContext.DETAILED_LEVEL, graph, "FullUnroll %s", loop);
                        peeled = true;
                        break;
                    }
                }
                dataCounted.deleteUnusedNodes();
            } while (peeled);
        }
    }

    @Override
    public boolean checkContract() {
        return false;
    }
}