This paper presents a theoretical investigation of the neuromorphic XOR operation utilizing a polarizationswitched high-speed photonic spiking neuron based on QD spin-VCSEL. The principles and working mechanism of the neuron are explored, emphasizing the role of pump components on the spike information processing. Temporal maps and time traces are used to illustrate the neuron's behavior and dynamics. By employing the right discrimination levels on pump ellipticity, all four XOR patterns ('00 ', '01', '10', and '11') are effectively processed by the neuron. The performance of the XOR operation is evaluated in terms of processing speed, utilizing a success rate based on spike firing above an intensity threshold. The processing speed can reach up to 4 Gb/s allowing future exciting routes for information processing in neuromorphic computing applications.