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PUNPCKHBW

Unpacks high bytes of words. For each word-sized element in the source, the instruction extracts the high byte and replicates it into two consecutive bytes in the destination.

The following table covers the supported source and destinations.

DO NOT support LOCK

This instruction is available in 32-bit and 64-bit modes. It requires SSE2 support.

The instruction operates on XMM registers; using this instruction on non-XMM registers SHALL result in an invalid operation. The destination register is overwritten, so the source register MUST be preserved in a separate register if the original data is required.