/**

 * WinPR: Windows Portable Runtime

 * C Run-Time Library Routines

 *

 * Copyright 2015 Thincast Technologies GmbH

 * Copyright 2015 Bernhard Miklautz <bernhard.miklautz@thincast.com>

 *

 *

 * Licensed under the Apache License, Version 2.0 (the "License");

 * you may not use this file except in compliance with the License.

 * You may obtain a copy of the License at

 *

 *     http://www.apache.org/licenses/LICENSE-2.0

 *

 * Unless required by applicable law or agreed to in writing, software

 * distributed under the License is distributed on an "AS IS" BASIS,

 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

 * See the License for the specific language governing permissions and

 * limitations under the License.

 */

#ifndef WINPR_INTRIN_H

#define WINPR_INTRIN_H

#ifndef _WIN32

/**

 * __lzcnt16, __lzcnt, __lzcnt64:

 * http://msdn.microsoft.com/en-us/library/bb384809/

 *

 * Beware: the result of __builtin_clz(0) is undefined

 */

#if (__GNUC__ > 4) || ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 2))

static INLINE UINT32 __lzcnt(UINT32 _val32)

{

	return ((UINT32)__builtin_clz(_val32));

}

static INLINE UINT16 __lzcnt16(UINT16 _val16)

{

	return ((UINT16)(__builtin_clz((UINT32)_val16) - 16));

}

#else /* (__GNUC__ > 4) || ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 2) */

static INLINE UINT32 __lzcnt(UINT32 x)

{

	unsigned y;

	int n = 32;

	y = x >> 16;

	if (y != 0)

	{

		n = n - 16;

		x = y;

	}

	y = x >> 8;

	if (y != 0)

	{

		n = n - 8;

		x = y;

	}

	y = x >> 4;

	if (y != 0)

	{

		n = n - 4;

		x = y;

	}

	y = x >> 2;

	if (y != 0)

	{

		n = n - 2;

		x = y;

	}

	y = x >> 1;

	if (y != 0)

		return n - 2;

	return n - x;

}

static INLINE UINT16 __lzcnt16(UINT16 x)

{

	return ((UINT16)__lzcnt((UINT32)x));

}

#endif /* (__GNUC__ > 4) || ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 2) */

#endif /* _WIN32 */

#endif /* WINPR_INTRIN_H */