tiny.simd.phastPositionPairFromHashesAndSeeds

1pub fn positionPairFromHashesAndSeeds(2    placement: Placement,3    comptime D: type,4    first_hashes: D.Vector,5    second_hashes: D.Vector,6    first_seeds: D.Vector,7    second_seeds: D.Vector,8) VectorPair(D) {9    const D16 = D.repartition(u16);10    var combined: D16.Vector = undefined;11    inline for (0..D.lane_count) |lane| {12        combined[lane] = @as(u16, @truncate(first_hashes[lane] >> 16)) +%13            @as(u16, @truncate(first_seeds[lane]));14        combined[D.lane_count + lane] =15            @as(u16, @truncate(second_hashes[lane] >> 16)) +%16            @as(u16, @truncate(second_seeds[lane]));17    }18    const within = hash16Vector(D16, combined);19    const offsets: D.Vector = @splat(placement.num_slice_offsets);20    const mask: D.Vector = @splat(placement.slice_mask);21    var result: VectorPair(D) = .{22        .first = multiply.mulHigh(D, first_hashes, offsets),23        .second = multiply.mulHigh(D, second_hashes, offsets),24    };25    inline for (0..D.lane_count) |lane| {26        result.first[lane] += @as(u32, within[lane]) & mask[lane];27        result.second[lane] += @as(u32, within[D.lane_count + lane]) & mask[lane];28    }29    return result;30}

1pub const phastPositionPairFromHashesAndSeeds = phast.phastPositionPairFromHashesAndSeeds;