CS 3853 Computer Architecture Chapter 3 Section 4 Example Answers


Modification 5: DIV.D uses F2 instead of F0 and there are 2 multiply functional units

Instruction
Reservation
Station
Execution
Unit
Issue
Cycle
Ex Start
Cycle
Ex End
Cycle
Memory
Cycle
CDB
cycle
Write
dest
L.D    F6,32(R2)Load1ALU12234F6
L.D    F2,44(R3)Load2ALU23345F2
MUL.DF0,F2,F4Mult1fmul1361516F0
SUB.DF8,F2,F6Add1fadd4678F8
DIV.DF10,F2,F6Mult2fmul2564546F10
ADD.DF6,F8,F2Add2fadd691011F6
Note: The DIV.D issues in cycle 5 and both operands are available for it to start execution on cycle 6.