Need use stmdb and ldmia instructions for the descending stack mov

UIN:

b. If you want to fix the problem, how do you use STM and LDM type instruction (loading and storing multiple registers instructions; need to modify them for stack operation) to fix the problem (place them in the correct locations in above three potion of codes as well as provide a complete and correct instruction syntax).

Only need to consider cases for the descending stack. Assume: SP is the top of address in astack.

44 BL SQ -------------------- PC = 40, LR = 28

28 BX LR --------------------- PC = LR = 28(?), here is the conflict happens since LR ≠

SQ:
40 MUL R0, R0
44 BX LR