360 Assembly/360 Instructions/CP
Compare Packed Decimal Instruction, format
The data string located at the storage address specified by operand-2 (b2+d2) is compared to the data string located at the storage address specified by operand-1 (b1+d1).
The operands may be different lengths with a maximum length of 16 bytes (or 31 digits since this is packed) for each operand. This is an arithmetic comparison.