1. An instruction generation apparatus which generates an output process instruction group including a plurality of instructions to be executed by a computer, said apparatus comprising: a branch-instruction generating unit configured to generate, as a part of the output process instruction group, a branch instruction which causes a processing route to branch to a first process instruction so that the computer executes the first process instruction, the first process instruction causing the computer to assign data to an assign-target variable; and a dependent-process-instruction generating unit configured to generate, as a part of the output process instruction group, a dependent process instruction dependent on the data assigned to the assign-target variable, the dependent process instruction causing the computer to execute a predetermined process in the output process instruction group onward when the data indicates predetermined contents, and the data assigned to the assign-target variable indicating a result of the first process instruction executed by the computer according to the branch instruction.