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PMAXUB

Compares two unsigned 8-bit integers and stores the maximum value in the destination.

The following table covers the supported source and destinations.

DO NOT support LOCK

This instruction is only available in 64-bit mode and 32-bit mode. It requires the SSE4.1 instruction set extension to be supported by the processor.

The instruction operates on packed data; therefore, the number of elements processed depends on the size of the XMM registers (128-bit). Failure to align memory operands (if applicable via related load/store instructions) may result in performance degradation or faults depending on the alignment check flag.