///////////////////////////////////////////////////////////////////////////

//

// Copyright (c) 2002, Industrial Light & Magic, a division of Lucas

// Digital Ltd. LLC

// 

// All rights reserved.

// 

// Redistribution and use in source and binary forms, with or without

// modification, are permitted provided that the following conditions are

// met:

// *       Redistributions of source code must retain the above copyright

// notice, this list of conditions and the following disclaimer.

// *       Redistributions in binary form must reproduce the above

// copyright notice, this list of conditions and the following disclaimer

// in the documentation and/or other materials provided with the

// distribution.

// *       Neither the name of Industrial Light & Magic nor the 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 IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR

// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT

// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,

// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT

// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,

// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY

// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT

// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE

// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

//

///////////////////////////////////////////////////////////////////////////

#include <iostream>

#include <iomanip>

using namespace std;

//-----------------------------------------------------

// Compute a lookup table for float-to-half conversion.

//

// When indexed with the combined sign and exponent of

// a float, the table either returns the combined sign

// and exponent of the corresponding half, or zero if

// the corresponding half may not be normalized (zero,

// denormalized, overflow).

//-----------------------------------------------------

void

initELut (unsigned short eLut[])

{

    for (int i = 0; i < 0x100; i++)

    {

	int e = (i & 0x0ff) - (127 - 15);

	if (e <= 0 || e >= 30)

	{

	    //

	    // Special case

	    //

	    eLut[i]         = 0;

	    eLut[i | 0x100] = 0;

	}

	else

	{

	    //

	    // Common case - normalized half, no exponent overflow possible

	    //

	    eLut[i]         =  (e << 10);

	    eLut[i | 0x100] = ((e << 10) | 0x8000);

	}

    }

}

//------------------------------------------------------------

// Main - prints the sign-and-exponent conversion lookup table

//------------------------------------------------------------

int

main ()

{

    const int tableSize = 1 << 9;

    unsigned short eLut[tableSize];

    initELut (eLut);

    cout << "//\n"

	    "// This is an automatically generated file.\n"

	    "// Do not edit.\n"

	    "//\n\n";

    cout << "{\n    ";

    for (int i = 0; i < tableSize; i++)

    {

	cout << setw (5) << eLut[i] << ", ";

	if (i % 8 == 7)

	{

	    cout << "\n";

	    if (i < tableSize - 1)

		cout << "    ";

	}

    }

    cout << "};\n";

    return 0;

}