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PSHUFHW

The PSHUFHW instruction shuffles two 16-bit words from a source operand according to an immediate byte value and stores the result in a destination operand. For each 16-bit word in the destination, the instruction selects one of the two 16-bit words from the source based on the corresponding bits of the immediate value.

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

DO NOT support LOCK

This instruction SHALL be executed in 64-bit mode or compatibility mode. It requires the SSE3 extension set to be supported by the processor.

The immediate value is used as a control mask where bits 1:0 select the word for the first 16-bit element of the destination, and bits 3:2 select the word for the second 16-bit element. If the selection bits are 0, the first 16-bit word of the source is chosen; if 1, the second 16-bit word is chosen. Bits 7:4 of the immediate value are ignored. Failure to use an SSE3-capable processor SHALL result in an invalid opcode exception.