block.h

/* ScummVM - Graphic Adventure Engine
 *
 * ScummVM is the legal property of its developers, whose names
 * are too numerous to list here. Please refer to the COPYRIGHT
 * file distributed with this source distribution.
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program 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 for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 */

#ifndef STARK_TOOLS_BLOCK_H
#define STARK_TOOLS_BLOCK_H

#include "common/array.h"

namespace Stark {
namespace Tools {

class CFGCommand;
struct ControlStructure;

class Block {
public:
    Block();

    void appendCommand(CFGCommand *command);

    Common::Array<CFGCommand *> getLinearCommands() const;

    CFGCommand *getConditionCommand() const;

    bool isEmpty() const;

    bool isCondition() const;

    void setBranches(Block *trueBranch, Block *falseBranch);
    void setFollower(Block *follower);
    void addPredecessor(Block *predecessor);
    Block *getTrueBranch() const;
    Block *getFalseBranch() const;
    Block *getFollower() const;

    void print() const;

    bool hasControlStructure() const;
    ControlStructure *getControlStructure() const;
    void setControlStructure(ControlStructure *controlStructure);

    bool isInfiniteLoopStart() const;
    void setInfiniteLoopStart(bool infiniteLoopStart);

    bool allowDuplication() const;

    // Graph query methods
    bool hasPredecessor(Block *predecessor) const;
    bool hasSuccessor(Block *successor) const;
    Block *findMergePoint(Block *other);
    bool checkAllBranchesConverge(Block *junction) const;

private:
    bool hasPredecessorIntern(Common::Array<const Block *> &visited, Block *predecessor) const;
    bool hasSuccessorIntern(Common::Array<const Block *> &visited, Block *successor) const;
    bool hasChildSuccessorIntern(Common::Array<const Block *> &visited, Block *child, Block *successor) const;
    Block *findMergePointIntern(Common::Array<const Block *> &visited, Block *other);
    Block *findChildMergePoint(Common::Array<const Block *> &visited, Block *child, Block *other) const;
    bool checkAllBranchesConvergeIntern(Common::Array<const Block *> &visited, Block *junction) const;
    bool checkChildConvergeIntern(Common::Array<const Block *> &visited, Block *child, Block *junction) const;

    uint16 getFirstCommandIndex() const;

    Common::Array<CFGCommand *> _commands;

    Block *_follower;
    Block *_trueBranch;
    Block *_falseBranch;
    Common::Array<Block *> _predecessors;

    ControlStructure *_controlStructure;
    bool _infiniteLoopStart;
};

struct ControlStructure {
    enum ControlStructureType {
        kTypeIf,
        kTypeWhile
    };

    ControlStructureType type;
    Block *condition;
    bool invertedCondition;
    Block *loopHead;
    Block *thenHead;
    Block *elseHead;
    Block *next;

    ControlStructure(ControlStructureType t);
};

} // End of namespace Tools
} // End of namespace Stark

#endif // STARK_TOOLS_BLOCK_H