CSE 141 Lecture 11: L11 11/9/17
9 Nov 2017
School
Department
Course
Professor
Document Summary
Assume the input data must be available @ the start of ex1 and the output is available after ex2. how many hardware stalls would be required? (assuming hardware forwarding wherever possible) lw r1, 0(r3) If1 if2 id ex m1 m2 wb lw r1, 8(r3) You don"t need r1 in ex; you need r1 in mem. Note: why stall in d and not ex? you already have the hazard detection unit for decode. you don"t need extra hardware for ex. A. software - compilers have a large window of instructions available to do recording to eliminate hazards. C. hardware - hardware knows @ runtime the actual dependencies and can exploit that knowledge for better recording. True. hardware can"t see as far, but hardware know the actual path, so it can move instructions without having to worry about the other paths. D. hardware - exposing the # of required stalls violates the abstraction between.
