, eax
This instruction performs a logical exclusive OR (XOR) on the EAX register with itself, effectively setting the value of EAX to 0. The XOR operator compares the corresponding bits of two operands and sets the corresponding bit in the result to 1 if the bits are different, and to 0 if the bits are the same. In this case, since both operands are the same (i.e., EAX with itself), all bits are set to 0, effectively clearing the register.