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PACKSSWB

Packs signed 16-bit integers from the source into signed 8-bit integers in the destination. The operation saturates values that are outside the range of a signed 8-bit integer (between -128 and 127) to the respective minimum or maximum value.

The table below covers the supported source and destination operands.

DO NOT support LOCK

This instruction is available in 64-bit mode and compatibility mode. It requires the SSE2 instruction set to be supported by the processor.

The instruction operates on XMM registers; using general-purpose registers or memory addresses as direct operands for the source or destination is invalid. To process data from memory, a separate MOV or MOVAPS/MOVUPS instruction MUST be used to load data into an xmm register first. Failure to ensure the data is correctly aligned when using aligned load instructions MAY result in a general-protection exception.