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#ifndef strings_h
#define strings_h

/* MSVC doesn't define ffs/ffsl. This dummy strings.h header is provided
 * for both */
#ifdef _MSC_VER
#  include <intrin.h>
#  pragma intrinsic(_BitScanForward)
static __forceinline int ffsl(long x)
{
	unsigned long i;

	if (_BitScanForward(&i, x))
		return (i + 1);
	return (0);
}

static __forceinline int ffs(int x)
{

	return (ffsl(x));
}

#  ifdef  _M_X64
#    pragma intrinsic(_BitScanForward64)
#  endif

static __forceinline int ffsll(unsigned __int64 x)
{
	unsigned long i;
#ifdef  _M_X64
	if (_BitScanForward64(&i, x))
		return (i + 1);
	return (0);
#else
// Fallback for 32-bit build where 64-bit version not available
// assuming little endian
	union {
		unsigned __int64 ll;
		unsigned   long l[2];
	} s;

	s.ll = x;

	if (_BitScanForward(&i, s.l[0]))
		return (i + 1);
	else if(_BitScanForward(&i, s.l[1]))
		return (i + 33);
	return (0);
#endif
}

#else
#  define ffsll(x) __builtin_ffsll(x)
#  define ffsl(x) __builtin_ffsl(x)
#  define ffs(x) __builtin_ffs(x)
#endif

#endif /* strings_h */