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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * 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).
 *
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 * 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.phases.common;

import org.graalvm.compiler.nodes.FrameState;
import org.graalvm.compiler.nodes.LoopExitNode;
import org.graalvm.compiler.nodes.StructuredGraph;
import org.graalvm.compiler.nodes.util.GraphUtil;
import org.graalvm.compiler.phases.Phase;

public class RemoveValueProxyPhase extends Phase {

    @Override
    protected void run(StructuredGraph graph) {
        for (LoopExitNode exit : graph.getNodes(LoopExitNode.TYPE)) {
            exit.removeProxies();
            FrameState frameState = exit.stateAfter();
            if (frameState != null && frameState.isExceptionHandlingBCI()) {
                // The parser will create loop exits with such BCIs on the exception handling path.
                // Loop optimizations must avoid duplicating such exits
                // We clean them up here otherwise they could survive until code generation
                exit.setStateAfter(null);
                GraphUtil.tryKillUnused(frameState);
            }
        }
        graph.setHasValueProxies(false);
    }
}