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PMULHUW

Multiplies two unsigned word operands and stores the upper 16 bits of the 32-bit result in the destination.

The following table covers what the source and destinations can be:

DO NOT support LOCK

This instruction is available only in 64-bit mode or compatibility mode. It requires the SSE4.1 instruction set extension.

The instruction operates on packed unsigned integers; using this instruction on signed integers will yield an incorrect result as it does not perform sign extension. The destination register is overwritten by the result, so the original data in the destination register MUST be preserved in another register if needed.