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ENCODEKEY128

ENCODEKEY128 encodes a 128-bit key used for the AES-NI instruction set. It takes a 128-bit value from a source and transforms it into an expanded key stored in the destination.

The table below covers what the source and destinations can be.

DO NOT support LOCK

This instruction is only available when the AES-NI feature is enabled in the processor. It is supported in both 32-bit and 64-bit modes.

The instruction requires the destination register to be an XMM register. Using a general-purpose register or a memory operand as a destination SHALL result in an invalid opcode exception. Failure to properly initialize the source XMM register with a valid 128-bit key will result in the generation of an incorrect expanded key without triggering a processor exception.