/**
* 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 */