If the source register (SRC1)'s LSB is cleared (the number is even), then either :
Short version : the destination register (SRC2) is cleared
Long version : the destination register (SRC2) is set to the value of Imm16 (sign-extended).
This is one of the conditional instructions of the CMOV group, see also : CLR, CZ/CNZ, CNO/CE, CS/CNS.
This instruction is also aliased from CE.