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// vclmulh.vv vd, vs2, vs1, vm
#include "zvk_ext_macros.h"
require_zvbc;
require(P.VU.vsew == 64);
VI_VV_ULOOP
({
// Perform a carryless multiplication 64bx64b on each 64b element,
// return the high 64b of the 128b product.
// <https://en.wikipedia.org/wiki/Carry-less_product>
vd = 0;
for (std::size_t bit_idx = 1; bit_idx < sew; ++bit_idx) {
const reg_t mask = ((reg_t) 1) << bit_idx;
if ((vs1 & mask) != 0) {
vd ^= ((reg_t)vs2) >> (sew - bit_idx);
}
}
})
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