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Assume a program requires the execution of 50 x 106 FP instructions, 110 x 106 INT instructions, 80 x 106 L/S instructions, and 16 x 106 branch instructions. The CPI for each type of instruction is 1 1, 4, and 2, respectively. Assume that the processor has a 2 GHz clock rate 1.141 [10] <$1.10 By how much must we improve the CPI of FP instructions if we want the program to run two times faster?

Answer

In order to achieve a two-fold improvement in program speed, it is necessary to enhance the CPI of FP instructions from 1 to 5.859375. The execution time of the program can be calculated using the formula: Execution Time = (Number of Instructions x CPI) / Clock Rate. The total number of instructions can be calculated as follows: Total Instructions = 50 * 10⁶ FP instructions + 110 * 10⁶ INT instructions + 80 * 10⁶ L/S instructions + 16 * 10⁶ branch instructions, giving a total of 256 x 10⁶ instructions. The current CPI for the program can be determined as follows: CPI = (50 * 1 + 110 * 1 + 80 * 4 + 16 * 2) / 256, which equals 1.8125. Accordingly, the current execution time of the program is calculated as: Execution Time = (256 * 10⁶ * 1.8125) / (2 * 10⁹) = 0.29296875 seconds. To speed up the program by a factor of two, it is required to reduce the execution time to 0.146484375 seconds. The formula: New CPI = (Execution Time x Clock Rate) / (Number of Instructions x 2) is used to calculate the new CPI for the FP instructions. By rearranging the formula, the new CPI can be derived as: New CPI = (Execution Time x Clock Rate) / (Number of Instructions x 2) = (0.146484375 * 2 * 10⁹) / (50 * 10⁶ * 1) = 5.859375. Therefore, to achieve a two-fold improvement in program speed, the CPI of FP instructions needs to be enhanced from 1 to 5.859375. There are multiple optimization methods that can be employed for this purpose, including the usage of SIMD instructions, optimizing memory access, and reducing data dependencies. Additional information on CPI can be found at brainly.com/question/14787822 #SPJ4.