/******************************************************************************
 * Copyright (c) 2013-2014, Texas Instruments Incorporated - http://www.ti.com/
 *   All rights reserved.
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 *         notice, this list of conditions and the following disclaimer.
 *       * Redistributions in binary form must reproduce the above copyright
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 *         documentation and/or other materials provided with the distribution.
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 *         names of its contributors may be used to endorse or promote products
 *         derived from this software without specific prior written permission.
 *
 *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 *   AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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#ifndef _genfile_cache_
#define _genfile_cache_

#include <llvm/Support/raw_ostream.h>
#include <llvm/IR/Module.h>
#include <llvm/Bitcode/ReaderWriter.h>

#include <boost/lexical_cast.hpp>
#include <boost/crc.hpp>

#include <sys/stat.h>

#include <string>
#include <iostream>
#include <sstream>
#include <vector>
#include <stdint.h>
#include "u_locks_pthread.h"
#include "database.h"

class genfile_cache
{
  public:
    std::string lookup   (llvm::Module *module, std::string options);
    void        remember (const char *outfile, llvm::Module *module, 
                          std::string options);

    /*-------------------------------------------------------------------------
    * Thread safe instance function for singleton behavior
    *------------------------------------------------------------------------*/
    static genfile_cache* instance ()
    {
        static Mutex Cache_instance_mutex;
        genfile_cache* tmp = pInstance;

        __sync_synchronize();

        if (tmp == 0)
        {
            ScopedLock lck(Cache_instance_mutex);

            tmp = pInstance;
            if (tmp == 0)
            {
                char *user = getenv("USER");
                tmp = new genfile_cache("/tmp/opencl_ofdb_" + string(user));
                __sync_synchronize();
                pInstance = tmp;
            }
        }
        return tmp;
    }


  private:
    static genfile_cache* pInstance;
    std::string p_dbname;
    Database    p_database;

  private:
    genfile_cache(std::string db_name) : p_dbname(db_name), p_database(db_name.c_str())
    {
        p_database.query("create table if not exists "
                "programs(hash integer, value string);");
    }

    uint32_t convert_mod2crc (llvm::Module *module, std::string options);
    uint32_t get_crc         (std::string& my_string);

    genfile_cache(const genfile_cache&);              // copy ctor disallowed
    genfile_cache& operator=(const genfile_cache&);   // assignment disallowed
};

#endif // _genfile_cache_