/*
 * Copyright (c) 2011, Oracle and/or its affiliates. All rights reserved.
 * 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.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */
package com.oracle.max.graal.compiler.phases;

import java.util.*;

import com.oracle.max.graal.compiler.*;
import com.oracle.max.graal.compiler.debug.*;
import com.oracle.max.graal.compiler.ir.*;
import com.oracle.max.graal.compiler.schedule.*;
import com.oracle.max.graal.graph.*;

public class LoweringPhase extends Phase {
    @Override
    protected void run(final Graph graph) {
        final IdentifyBlocksPhase s = new IdentifyBlocksPhase(false);
        s.apply(graph);

//        for (Block b : s.getBlocks()) {
//            TTY.println("Java block for block " + b.blockID() + " is " + b.javaBlock().blockID());
//        }


        for (final Node n : graph.getNodes()) {
            if (n instanceof FixedNode) {
                LoweringOp op = n.lookup(LoweringOp.class);
                if (op != null) {
                    op.lower(n, new LoweringTool() {
                        @Override
                        public Node createStructuredBlockAnchor() {
                            Block block = s.getNodeToBlock().get(n);
                            Block javaBlock = block.javaBlock();
                            Node first = javaBlock.firstNode();
                            if (!(first instanceof Anchor) && !(first instanceof Merge)) {
                                Anchor a = new Anchor(graph);
                                assert first.predecessors().size() == 1;
                                Node pred = first.predecessors().get(0);
                                int predIndex = first.predecessorsIndex().get(0);
                                a.successors().setAndClear(Instruction.SUCCESSOR_NEXT, pred, predIndex);
                                pred.successors().set(predIndex, a);
                                javaBlock.setFirstNode(a);
                            }
                            return javaBlock.firstNode();
                        }
                    });
                }
            }

        }
    }

    public interface LoweringTool {
        Node createStructuredBlockAnchor();
    }

    public interface LoweringOp extends Op {
        void lower(Node n, LoweringTool tool);
    }
}