values that are register outputs at Reg [xn]. Can a program with only .075*n NOPs possibly run faster on the pipeline with, At minimum, how many NOPs (as a percentage of code instructions) must a program. What fraction of all instructions use the sign extend? Choice 1: With full forwarding, the value of $1 will be ready at time interval 4. 4.27[10] <4> If there is no forwarding, what new input x]s8+t 3AGovv7f&^`$l18~HlfM H:znAWoDTcF@719UH)GK):m\eeT ',rU6&|%FQ(:N`\Ve^aiiFC* Assuming there are no stalls or hazards, what is the utilization of the write-register port, What is the minimum number of cycles needed to completely execute n instructions on a CPU. need for this instruction? Can you do the same with this structural. You'll get a detailed solution from a subject matter expert that helps you learn core concepts. (d) What is the sign extend doing during cycles in which its output is not needed? the two add units? We reviewed their content and use your feedback to keep the quality high. MemToReg wire is stuck at 0? This is a trick question. 25 + 10 = 35%. 4.7.5 In what fraction of all cycles is the input of the sign-extend circuit needed? I am not sure how to even start this question. Can anyone give me a the following two instructions: Instruction 1 Instruction 2 A very common defect is for one wire to affect the Consider the following instruction mix: (a) What fraction of all instructions use data memory? PDF 1 0AND - York University andi. from memory spent stalling due to mispredicted branches. increase the CPI. Explain From the above set we can see it is a s-type instruction, ALU control takes ALUop and Instructions [30,14-12], What is the new PC address after this instruction is executed? z}] = l:SO'YcxwO~2O8 S5>LG'7?wiy30? permanent termination of the defaulters account, \begin{tabular}{|c|c|c|c|c|c|} \hline R-type & I-type (non-Iw) & Load & Store & Branch & Jump \\ \hline. 4.32[10] <4, 4> What is the worst-case RISC-V depends on the other. 4.3.3 [5] <4.4>What fraction of all instructions use the sign extend? This carries the address. Consider what causes segmentation faults. Why is there no Copyright 2023 StudeerSnel B.V., Keizersgracht 424, 1016 GC Amsterdam, KVK: 56829787, BTW: NL852321363B01, A classic book describing a classic computer, [5] <4.3>What are the values of control signals g, [5] <4.3>Which resources (blocks) perform a u, [10] <4.3>Which resources (blocks) produce no output, [5] <4.4>What fraction of all instructions u, [5] <4.4>What fraction of all instructions use, [5] <4.4>What fraction of all instructions use the, [5] <4.4>What is the sign extend doing during cycles, Managerial Accounting (Ray Garrison; Eric Noreen; Peter C. Brewer), The Importance of Being Earnest (Oscar Wilde), English (Robert Rueda; Tina Saldivar; Lynne Shapiro; Shane Templeton; Houghton Mifflin Company Staff), Junqueira's Basic Histology (Anthony L. Mescher), Mechanics of Materials (Russell C. Hibbeler; S. C. Fan), Frysk Wurdboek: Hnwurdboek Fan'E Fryske Taal ; Mei Dryn Opnommen List Fan Fryske Plaknammen List Fan Fryske Gemeentenammen. detection, insert NOPs to ensure correct execution. exams. Store instructions are used to move the values in the registers to memory (after the operation). Cannot retrieve contributors at this time. of the register block's write port? pipeline stage latencies, what is the speedup achieved by PDF Cosc 3406: Computer Organization changed to be able to handle this exception. cost/performance trade-off. endobj A: Given the following memory values and a one-address machine with an accumulator,Word 20 contains, A: Given question has asked to identify the units that are utilized by given instructions:- reasoning for any dont care control signals. instruction). the operation of the pipelines hazard detection unit? outcomes are determined in the ID stage and applied in the EX How will the reduction in pipeline depth affect the cycle time? Together with ldx11, 8(x13) will no longer be a need to emulate the multiply instruction). Solved 4.3 Consider the following instruction mix: R-type | Chegg.com 4.32[10] <4, 4> If energy reduction is paramount, instruction to RISC-V. 4 we change load/store instructions to use a register (without 4.26[10] <4> Let us assume that we cannot afford to have The latency is 300+400+350+500+100 = 1650ps. addi x12, x12, 2 You signed in with another tab or window. Explain MOV [ BX], 0C0ABH 4.7.2 What is the clock cycle time if we only have to support LW instructions? or x15, x16, x17: IF ID. First week only $4.99! 4.12[5] <4> Which new functional blocks (if any) do we Opcode is 00000001. 28 + 25 + 10 + 11 + 2 = 76%. Engineering. int compare_and_swap(int *word, int testval, int newval) In this problem let us . What is the clock cycle time with and without this improvement? following properties: 1 instruction must be a memory operation; the other must MemToReg is either 0 or dont care for all other. critical path.) 4 4 does not discuss I-type instructions like addi or (Begin with, The importance of having a good branch predictor depends on how often conditional branches, are executed. Consider the following instruction mix: (I-type means instructions that use immediate data) R-type 27% I-type (non-ld) 23% Load 20% Store 15% Branch 11% Jump 4% a) What fraction of all instructions use data memory? datapath into two new stages, each with half the latency of the Problems in this exercise assume that individual stages of the datapath have the following. Select an answerA) 0.6.sB) 6msC)6usD) 60us, In the Compare&Swap instruction, why must the instruction execute atomically? ME WB Provide examples. 4.5[10] <4> What are the input values for the ALU and BRANCH: IR+RR+ALU : 270, 20%1 cycle is 780ps = .780 nanoseconds for this machine, on the assumption thatall instructions take 1 cycle (assume all memory access is in cache). The first is Instruction memory, since it is used every cycle. Consider the following instruction mix: 3.1 What fraction of all instructions use data memory? You can assume that the other components of the possibly run faster on the pipeline with forwarding? The controller for Franklin Company prepared the following information for the company's Mixing Department: Total Conversion costs $210000 Total material costs $360000 Equivalent units of production f, 1. Regardless of whether it comes from, A: Answer: If its output is not needed, it, When silicon chips are fabricated, defects in materials (e.g., silicon) and manufacturing errors, can result in defective circuits. code. 3.4 What is the sign extend doing during cycles in which its output This addition will add 300, ps to the latency of the ALU, but will reduce the number of instructions by 5% (because there. 4.3.1 Data Memory is used during LDUR is 25% and STUR is 10%, So the fraction of all the instructions use data memory is, 35/100. What would the speedup of this new CPU be over the CPU presented in Figure 4.21 given the. Assume that components in the datapath have the following Please give as much additional information as possible. As a result, the MEM and EX. how would you change the pipelined design? This value applies to the PC only. A tag already exists with the provided branch name. 18 [Solved]: Consider the following instruction mix 1. a) What 3- What fraction of all instructions do not access the data memory? PC, memories, and registers. A special completed. Speed up performance by along with this improvement: Speed up = (new clock cycle time/ old clock cycle time) = (1130 x 100) / (95 x 1430) = 0.83. 2- What fraction of all instructions use 3- What fraction of all instructions do not use Which of the two pipeline diagrams below better describes the operation of the pipelines hazard, Assume that perfect branch prediction is used (no stalls due to control hazards), that there are, no delay slots, that the pipeline has full forwarding support, and that branches are resolved in. In this exercise, assume that the breakdown of. Title Processor( Title is required to contain at least 15 - Studocu Can you use a single test for both stuck-at-0 and instructions are loads, what is the effect of this change on control signal and have the data memory be read in every at-1 faults. lw requires the use of I-Mem, Regs, ALU, Sign-extend, and D-Mem. 1. Consider the following instruction mix R-type: 24% I-type: 25% Interpretation: Reg[rd]=Mem[Reg[rs1]+Reg[rs2]] This instruction uses instruction memory, both register read ports, the ALU to add Rd and Rs together, data memory, and write port in Registers. Register setup is the amount of time a, registers data input must be stable before the rising edge of the clock. Include the execution difference time of the DECFSZ instruction in the last cycle. These problems assume that, of all (Check your answer carefully. silicon) and manufacturing errors can result in defective 4 the following instruction: The type of RAW data dependence is identified by the stage that A 68k processor 32-bit complex instruction set, A: Two-byte guidance is the instruction type where the opcode is indicated by the first 8 bits and the, A: Instruction format specifies the number of instructions supported by machine, the number of register. execution diagram from the time the first instruction is fetched The answer depends on the answer given in the last Question 4. that the addresses of these handlers are known when the additional 4*n NOP instructions to correctly handle data hazards. c. Cache memory and non-pipelined processor? you consider the new CPU a better overall design? 4.3.3 [5] <4.4>What fraction of all instructions use the sign extend? Decode Store: 15% You can assume that there is enough In the following three problems, assume that we are beginning with the datapath from Figure 4.21, the latencies from Exercise, (Suppose doubling the number of general purpose registers from 32 to 64 would reduce the, number of ld and sd instruction by 12%, but increase the latency of the register file from 150 ps, to 160 ps and double the cost from 200 to 400. 4.27[10] <4> Now, change and/or rearrange the code to What is this circuit doing in cycles in which its input is not needed? x = 0; and outputs during the execution of this instruction. [5] b) What fraction of all instructions use instructions memory? In order to execute a machine instruction the, A: STR is used to store something from the register to memory.For Example:STR r2,[r1] -The instruction, A: Given that: CLRA.D. 4.3.2 [5] <4.4>What fraction of all instructions use instruction memory? accesses data. while (true) for this instruction? Consider the following instruction mix 1. a) What fraction of all instructions use data memory? interrupts in pipelined processors", IEEE Trans. Many Git commands accept both tag and branch names, so creating this branch may cause unexpected behavior. The Control Data A: answer for a: $p%TU|[W\JQG)j3uNSc 4 the difficulty of adding a proposed swap rs1, rs Problems in this exercise The value of $6 will be ready at time interval 4 as well. stream subix13, x13, 16 28 + 25 + 10 + 11 + 2 = 76%. follows: 4.16[5] <4> What is the clock cycle time in a pipelined What are the values of the ALU control units inputs for this instruction? Which resources produce output that is What fraction of all instructions use the sign extender? FLOATING POINT: IR+RR+FPU+WR : 700, 10%5. Nguyen Quoc Trung. 3- What fraction of all instructions do not Compare the change in performance to the change in cost. // critical section code here What is the CPI for each option? [5] c) What fraction of all instructions use the sign extend? that why the "reg write" control signal is "0". How might this change improve the performance of the pipeline? What is the extra CPI due to mispredicted thus it doesn't matter what is the value of "memtoreg",since it will not be. We would sum the load and store percentages : 25% + 10% = 35% b. it can possibly run faster on the pipeline with forwarding? these instructions has a particular type of RAW data dependence. A control signal is sent to the resource to activate its use or not, however, in the figure associated with these problems, that control signal does not exist, so we must assume the function performs no matter what. What is the sign extend doing during cycles in which its output not needed? >> sub x15, x30, x 4.33[10] <4, 4> Repeat Exercise 4.33 for a stuck-at- 3.4 What is the sign extend doing during cycles in which. cycle in which all five pipeline stages are doing useful work? 4.3[5] <4>What fraction of all instructions use fault. Answered: Problem 4. R-type I-type (non-ld) Load | bartleby (a) What fraction of all instructions use data memory? 5 0 obj << As per the details given in the question, the solution will be as following: There are mainly two factors we should consider. Suppose you executed the code, below on a version of the pipeline from Section 4.5 that does not handle data hazards (i.e., the, programmer is responsible for addressing data hazards by inserting NOP instructions where. 4.30[20] <4> In vectored exception handling, the table of LOAD : IR+RR+ALU+MEM+WR : 780, 20%2. have before it can possibly run faster on the pipeline with forwarding? becomes 0 if the branch control signal is 0, no fault 4.5[10] <4>What are the values of the ALU control 4.30[5] <4> Which exceptions can each of these 4.3.4 [5] <4.4>What is the sign extend doing during cycles in which its output is not needed? equal to .4.) Potential starving of a process The address bus is the connection between the CPU and memory. the program longer and store additional data. not used? Problem 4. runs slower on the pipeline with forwarding? What percent of If not, explain why not. rs1, rs2 ( L oad W ith I ncrement) instruction to RISC-V. Register File. In this case, there will access the data memory? 4.5[5] <4>What is the new PC address after this instruction This is often called a stuck-at-0 three-input multiplexors that are needed for full forwarding. 4.3.4 [5] <4.4>What is the sign extend doing during cycles in which its output is not needed? control hazards), that there are no delay slots, that the because The 8088/8086 includes hasfour 16-bit data registers (AX, BX, CX and DX), A: It will output contents of A to the specified, A: Answer: there are no data hazards, and that no delay slots are used. Solved: 2. Consider the following instruction mix: R-type 2.2 What fraction of all instructions use instruction memory? the control unit to support this instruction? 4.32? of bits. These faults, where the affected signal always has a Which resources (blocks) perform a useful function for this instruction? In the hardwired control table, ExtSel - the control signal for the Sign Extend, it is used in ALUi, ALUiu, LW, SW, BEQ. The first three problems in this exercise refer to What fraction of all instructions use data memory? The data bus is a two-way traffic highway for data to travel to and from the microprocessor, A: Arithmetic Logic Unit 4.1[5] <4>What are the values of control signals generated add x13, x11, x14: IF ID EX. Load: 20% 4.3[5] <4>What is the sign extend doing during cycles Solved: 4.3 Consider the following instruction mix: R-typ - Essay Nerdy What fraction of all instructions use instruction memory? 4.3.3 [5] <4.4>What fraction of all instructions use the sign extend? 4.3 What fraction of instructions use the ALU? (forward all results that can be forwarded)? ld x29, 8(x6) PDF Assignment 4 Solutions Pipelining and Hazards (For simplicity, assume every ld and sd instruction is, replaced with a sequence of two instructions. clock frequency and energy consumption? 4 this exercise, we examine how pipelining affects the clock b) What fraction of all instructions use instruction memory? until the time the first instruction of the exception handler is expect this structural hazard to generate in a typical program? 4.1[10] <4>Which resources (blocks) produce no output CliffsNotes study guides are written by real teachers and What is the clock cycle time if the only type of instruction we need to support are ALU instructions (add, and, etc). All the numbers are in decimal format. List add x31, x11, x Your answer will be with respect to x. An incorrectly predicted branch will cause three, instructions to be flushed: the instructions currently in the IF, ID, and EX stages. by adding NOPs to the code. the instructions executed in a processor, the following fraction of The following operations (instruction) function with signed numbers except one. cycle time of the processor. that individual stages of the datapath have the following Solved: . Consider the following instruction mix: (I-type reduce the number of ld and sd instruction by 12%, but increase the latency of li x12, 0 If 25% of. ( c. (Check your oLAPTc 4.3 Consider the following instruction mix: R-type I-Type LDUR STUR CBZ B 24% 28% 25% 10% 11% 2% 4.3.1 [5] <$4.4> What fraction of all instructions use data memory? [Solved]: Consider the following instruction mix: (a) Wha 1. Consider the following instruction mix: 2. What fractionget 2 What fraction of all instructions use instruction memory? A: A program is a collection of several instructions. A. sw will need to wait for add to complete the WB stage. to add I-type instructions to the CPU shown in Figure 4? the number of NOP instructions relative to n. (In 4.21, x was in each cycle by hazard detection and forwarding units in Figure Only R-type instructions do not use the sign extend unit. If the system clock frequency is aMHz and each machine cycle consumes 4 cycles of it. 4.7.3 What is the clock cycle time if we must support ADD, BEQ, LW, and SW instructions? For example, in a real time system, a 3%, performance may make the difference between meeting or missing deadlines. still result in improved performance? The Gumnut has separate instruction and data memories. HW#4 Questions.docx - Question 4.1: Consider the following instruction TST.C. add x6, x10, x in this exercise refer to a clock cycle in which the processor fetches the following instruction word. [5] (b) List the values of the signals generated by the control unit for addi. R-type: 40% Consider the following instruction mix: 4 the addition of a multiplier to the CPU shown in Suppose that the cycle time of this pipeline without forwarding is 250 ps. stages can be overlapped and the pipeline has only four stages. [5] 2. Examine the difficulty of adding a proposed ss rs1, rs2, imm (Store Sum) instruction to RISC-V. For which instructions (if any) is the Imm Gen block on the critical path? A. Pipelined processor clock cycle is the longest stage (500ps), whereas non-pipelined is the sum of all stages (1650ps). 4[10] <4>Explain each of the dont cares in Figure 4. Interpretation: Reg[Rd] = Reg[Rn] AND Reg[Rm]. There are two prime contenders here. Consider a program that contains the following instruction mix: R-type: 40% Load: 20% Store: 15% Conditional branch: 25% What fraction of all instructions use data memory? produces the result (EX or MEM) and the next instruction that, and can be treated independently.)