#ifndef SIMDJSON_HASWELL_BITMASK_H

#define SIMDJSON_HASWELL_BITMASK_H

#include "simdjson.h"

#include "haswell/intrinsics.h"

TARGET_HASWELL

namespace simdjson {

namespace haswell {

//

// Perform a "cumulative bitwise xor," flipping bits each time a 1 is encountered.

//

// For example, prefix_xor(00100100) == 00011100

//

really_inline uint64_t prefix_xor(const uint64_t bitmask) {

// There should be no such thing with a processor supporting avx2

// but not clmul.

__m128i all_ones = _mm_set1_epi8('\xFF');

__m128i result = _mm_clmulepi64_si128(_mm_set_epi64x(0ULL, bitmask), all_ones, 0);

return _mm_cvtsi128_si64(result);

}

} // namespace haswell

} // namespace simdjson

UNTARGET_REGION

#endif // SIMDJSON_HASWELL_BITMASK_H