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// license:BSD-3-Clause
// copyright-holders:Aaron Giles
//============================================================
//
// eivc.h
//
// Inline implementations for MSVC compiler.
//
//============================================================
#ifndef __EIVC__
#define __EIVC__
#include <intrin.h>
#pragma intrinsic(_BitScanReverse)
/***************************************************************************
INLINE BIT MANIPULATION FUNCTIONS
***************************************************************************/
/*-------------------------------------------------
count_leading_zeros - return the number of
leading zero bits in a 32-bit value
-------------------------------------------------*/
#ifndef count_leading_zeros
#define count_leading_zeros _count_leading_zeros
static inline uint8_t _count_leading_zeros(uint32_t value)
{
uint32_t index;
return _BitScanReverse((unsigned long *)&index, value) ? (index ^ 31) : 32;
}
#endif
/*-------------------------------------------------
count_leading_ones - return the number of
leading one bits in a 32-bit value
-------------------------------------------------*/
#ifndef count_leading_ones
#define count_leading_ones _count_leading_ones
static inline uint8_t _count_leading_ones(uint32_t value)
{
uint32_t index;
return _BitScanReverse((unsigned long *)&index, ~value) ? (index ^ 31) : 32;
}
#endif
#endif /* __EIVC__ */
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