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/**************************************************************************
*
* Copyright 2008 VMware, Inc.
* All Rights Reserved.
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the
* "Software"), to deal in the Software without restriction, including
* without limitation the rights to use, copy, modify, merge, publish,
* distribute, sub license, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so, subject to
* the following conditions:
*
* The above copyright notice and this permission notice (including the
* next paragraph) shall be included in all copies or substantial portions
* of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
* OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
* IN NO EVENT SHALL VMWARE AND/OR ITS SUPPLIERS BE LIABLE FOR
* ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*
**************************************************************************/
#include "bitscan.h"
#ifdef HAVE___BUILTIN_FFS
#elif defined(_MSC_VER) && (_M_IX86 || _M_ARM || _M_AMD64 || _M_IA64)
#else
int
ffs(unsigned i)
{
int bit = 0;
if (!i)
return bit;
if (!(i & 0xffff)) {
bit += 16;
i >>= 16;
}
if (!(i & 0xff)) {
bit += 8;
i >>= 8;
}
if (!(i & 0xf)) {
bit += 4;
i >>= 4;
}
if (!(i & 0x3)) {
bit += 2;
i >>= 2;
}
if (!(i & 0x1))
bit += 1;
return bit + 1;
}
#endif
#ifdef HAVE___BUILTIN_FFSLL
#elif defined(_MSC_VER) && (_M_AMD64 || _M_ARM || _M_IA64)
#else
int
ffsll(uint64_t val)
{
int bit;
bit = ffs((unsigned) (val & 0xffffffff));
if (bit != 0)
return bit;
bit = ffs((unsigned) (val >> 32));
if (bit != 0)
return 32 + bit;
return 0;
}
#endif
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