Assume that the following code should be executed in a 6-stage (IF(instruction fetch), ID(instruction decode), EX1(first step of execution), EX2(second step of execution), EX3 ( third step of execution), SR( save the result)) pipeline.

LOAD R1, # X LOAD R2, #Y ADD R3, R1, R2 STORE M(R10), R3 (store R3 in the memory location addressed by R10) LOAD R4, #Z SUB R5, R2, R4 STORE M(R20), R5

Hint: the first operand is the destination. a) Construct a space-time diagram . b) Find a valid reordering of the given code that will reduce the number of needed cycles, & then construct another space-time diagram for the reordered code.