1. An information processing system comprising: a first processor that executes instructions belonging to a first instruction set; a second processor that executes instructions belonging to a second instruction set; a first memory that stores a translation target program that is designed based on the first instruction set, the first memory being unaccessible by the second processor; a second memory that is accessible by the second processor; and a data transfer unit that transfers data between the first memory and the second memory, wherein the first processor operates to: read the translation target program from the first memory; determine each of instructions included in the translation target program is whether a memory access instruction; translate the instructions that are determined to be not the memory access instruction into instructions belonging to the second instruction set; and translate the instructions that are determined to be the memory access instruction into instruction sequence including a call instruction calling a data transfer library that is stored in the second memory, and wherein the second processor operates to: execute the translated instructions that belong to the second instruction set; and controls the data transfer unit to transfer the data between the first memory and the second memory in accordance with the instruction sequence.