I have a x86 assembly version of the basic AES algorithm I wrote when we briefly tried to remediate some 20 year old POS registers for PCI compliance. Turned out we didn't need it, but it was a great experience to write some assembler again.
I would be happy to share it if you feel it would be valuable. Please keep in mind that it is just the encryption portion, i.e. you supply it the Key and Data block and it returns the encrypted block. So you aren't getting anything that initializes a key, performs any salting, or any sort of rolling block encryption. Give it a 256-bit key, 256-bit data and get out 256-bit encrypted data.
I also have a version of it in .net c# which I wrote to prove my ASM.