Advanced Computer Architecture - Lecture 14: Instruction level parallelism. This lecture will cover the following: dynamic scheduling; tomasulo’s approach; scoreboard vs. tomasulo’s approach; tomasulo''s algorithm; FP adder reservation station; FP multiplier reservation station;...
CS 704 Advanced Computer Architecture Lecture 14 Instruction Level Parallelism (Dynamic Scheduling – Tomasulo’s Approach) Prof Dr M Ashraf Chughtai Today's Topics Recap - Lecture 13 Dynamic Scheduling Tomasulo’s Approach Summary MAC/VU-Advanced Computer Architecture Lecture 14 – Instruction Level Parallelism -Dynamic (3) Recap: Summary Instruction Level Parallelism in Hardware or Software SW parallelism dependencies defined by program result in hazards if HW cannot resolve HW exploiting ILP works when dependence cannot be determined at run time MAC/VU-Advanced Computer Architecture Lecture 14 – Instruction Level Parallelism -Dynamic (3) Recap … Cont’d Key idea of Scoreboard – Allow instructions behind stall to proceed It is accomplished by dividing the ID stage into two parts Issue the instruction in-order Read operand out-of-order MAC/VU-Advanced Computer Architecture Lecture 14 – Instruction Level Parallelism -Dynamic (3) Recap … Cont’d Scoreboard … Cont’d– Structural and data dependencies are checked at ID stage It facilitates out-of-order execution which results in outof-order completion MAC/VU-Advanced Computer Architecture Lecture 14 – Instruction Level Parallelism -Dynamic (3) Recap … Cont’d MAC/VU-Advanced Computer Architecture Lecture 14 – Instruction Level Parallelism -Dynamic (3) Recap … Cont’d MAC/VU-Advanced Computer Architecture Lecture 14 – Instruction Level Parallelism -Dynamic (3) Recap … Cont’d MAC/VU-Advanced Computer Architecture Lecture 14 – Instruction Level Parallelism -Dynamic (3) Recap … Cont’d MAC/VU-Advanced Computer Architecture Lecture 14 – Instruction Level Parallelism -Dynamic (3) Recap … Cont’d MAC/VU-Advanced Computer Architecture Lecture 14 – Instruction Level Parallelism -Dynamic (3) 10 MAC/VU-Advanced Computer Architecture Lecture 14 – Instruction Level Parallelism -Dynamic (3) 65 MAC/VU-Advanced Computer Architecture Lecture 14 – Instruction Level Parallelism -Dynamic (3) 66 MAC/VU-Advanced Computer Architecture Lecture 14 – Instruction Level Parallelism -Dynamic (3) 67 MAC/VU-Advanced Computer Architecture Lecture 14 – Instruction Level Parallelism -Dynamic (3) 68 MAC/VU-Advanced Computer Architecture Lecture 14 – Instruction Level Parallelism -Dynamic (3) 69 MAC/VU-Advanced Computer Architecture Lecture 14 – Instruction Level Parallelism -Dynamic (3) 70 MAC/VU-Advanced Computer Architecture Lecture 14 – Instruction Level Parallelism -Dynamic (3) 71 MAC/VU-Advanced Computer Architecture Lecture 14 – Instruction Level Parallelism -Dynamic (3) 72 MAC/VU-Advanced Computer Architecture Lecture 14 – Instruction Level Parallelism -Dynamic (3) 73 MAC/VU-Advanced Computer Architecture Lecture 14 – Instruction Level Parallelism -Dynamic (3) 74 MAC/VU-Advanced Computer Architecture Lecture 14 – Instruction Level Parallelism -Dynamic (3) 75 MAC/VU-Advanced Computer Architecture Lecture 14 – Instruction Level Parallelism -Dynamic (3) 76 MAC/VU-Advanced Computer Architecture Lecture 14 – Instruction Level Parallelism -Dynamic (3) 77 MAC/VU-Advanced Computer Architecture Lecture 14 – Instruction Level Parallelism -Dynamic (3) 78 Asslam-u-aLacum and ALLAH Hafiz MAC/VU-Advanced Computer Architecture Lecture 14 – Instruction Level Parallelism -Dynamic (3) 79 ... MAC/VU -Advanced Computer Architecture Lecture 14 – Instruction Level Parallelism -Dynamic (3) Recap … Cont’d MAC/VU -Advanced Computer Architecture Lecture 14 – Instruction Level Parallelism -Dynamic... MAC/VU -Advanced Computer Architecture Lecture 14 – Instruction Level Parallelism -Dynamic (3) 10 Recap … Cont’d MAC/VU -Advanced Computer Architecture Lecture 14 – Instruction Level Parallelism -Dynamic... Computer Architecture Lecture 14 – Instruction Level Parallelism -Dynamic (3) 30 MAC/VU -Advanced Computer Architecture Lecture 14 – Instruction Level Parallelism -Dynamic (3) 31 MAC/VU -Advanced Computer