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Optimize the AES library with x86 AES-NI instructions. The relevant existing assembly functions, aesni_set_key(), aesni_enc(), and aesni_dec(), are a bit difficult to extract into the library: - They're coupled to the code for the AES modes. - They operate on struct crypto_aes_ctx. The AES library now uses different structs. - They assume the key is 16-byte aligned. The AES library only *prefers* 16-byte alignment; it doesn't require it. Moreover, they're not all that great in the first place: - They use unrolled loops, which isn't a great choice on x86. - They use the 'aeskeygenassist' instruction, which is unnecessary, is slow on Intel CPUs, and forces the loop to be unrolled. - They have special code for AES-192 key expansion, despite that being kind of useless. AES-128 and AES-256 are the ones used in practice. These are small functions anyway. Therefore, I opted to just write replacements of these functions for the library. They address all the above issues. Acked-by: Ard Biesheuvel <ardb@kernel.org> Link: https://lore.kernel.org/r/20260112192035.10427-18-ebiggers@kernel.org Signed-off-by: Eric Biggers <ebiggers@kernel.org>