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#include <isl_config.h>
#if !HAVE_DECL_FFS && !HAVE_DECL___BUILTIN_FFS && HAVE_DECL__BITSCANFORWARD
#include <intrin.h>
/* Implementation of ffs in terms of _BitScanForward.
*
* ffs returns the position of the least significant bit set in i,
* with the least significant bit is position 1, or 0 if not bits are set.
*
* _BitScanForward returns 1 if mask is non-zero and sets index
* to the position of the least significant bit set in i,
* with the least significant bit is position 0.
*/
int isl_ffs(int i)
{
unsigned char non_zero;
unsigned long index, mask = i;
non_zero = _BitScanForward(&index, mask);
return non_zero ? 1 + index : 0;
}
#endif
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