mod(x,y) works for unsigned integers, but not for signed integers in nand2tetris. What changes should I make?

Question

@R2
M=0
@R0
D=M
@END
D, JEQ
@store
M=D 

(LOOP) @R1 D=D-M @REMAINDER D, JLT @EVENLY D, JEQ @LOOP 0, JMP (REMAINDER) @R1 D=D+M @R2 M=D (EVENLY) @store