hash3

    fn hash3(seed: u64, input: anytype, noalias secret: *const [192]u8) u64 {
        @branchHint(.unlikely);
        std.debug.assert(input.len > 0 and input.len < 4);

        const flip: [2]u32 = @bitCast(secret[0..8].*);
        const blk: u32 = @bitCast([_]u8{
            input[input.len - 1],
            @truncate(input.len),
            input[0],
            input[input.len / 2],
        });

        const key = @as(u64, flip[0] ^ flip[1]) +% seed;
        return avalanche(.h64, key ^ blk);
    }