bignum

Sorry for not submitting a pull request, I'm working on a bignum library and I saw your implementation of multiplication so I just want to point out that you can simplify it by doing the multiply and the add in one loop into the result bn as follow:

typedef unsigned int           u32;
typedef unsigned long long int u64;
void _bn_add_mul_u32(u32 *out, u32 *a, size_t a_len, u32 b)
{

Seen with @arnetheduck.

for uint128, stint properly generates add + adc (see status-im/nim-stint#10)

But for uint256+, the way carry is done will loop multiple time on the low half
https://github.com/status-im/nim-stint/blob/9993b9dca4a2dbf76bc432252ad4e8db944ae831/stint/private/uint_addsub.nim#L17-L29

Important for WASM codesize optimization.

• Benchmark suite.
• Compare with Rust.
• Compare with incoming javascript's BigInt.

Chai's members can be used to test that an array contains certain values, as determined by strict equality or optionally deep equality.

Neither of those is appropriate to test arrays of big numbers (although deep equality works, it isn't ideal). We could maybe make the bignumber property modify members to compare values using bignumber equ

Current CMAC implementation assumens a block cipher with 16 bytes block size.

This can be adjusted to take the cipher block size during initialization