Folding a constant into the instruction
Adding a small constant doesn't need a separate load. The compiler folds the number straight into the instruction with the immediate form addi rD, rA, imm — imm is the literal value, riding along inside the opcode:
addi r3, r3, 5 # r3 = r3 + 5
blr
That immediate field is signed and 16 bits wide, so it reaches from -32768 up to 32767; ask for a constant beyond that and the compiler splits the work across lis plus addi. You won't need that here, but it's worth remembering. And because the field is signed, the same addi can subtract too — that's the next lesson.
The immediate in the target addi is the constant you want.
Your task
Write adjust so it compiles to the target addi instruction.