Problem $2$

Consider that you have a code of $400,000$ instructions which is executed using a $16$ stages pipeline. It is expected that $20\%$ of the instructions will cause an exception $1.$ In order to handle the exception, it will take $3$ cycles to flush the pipeline, $7$ cycles to reload and $30$ cycles to execute the handler. The pipeline frequency is $2\mathrm{.}5GHz$

i$)$ How many cycles does it take to execute the code?

$3,200,000+5,120,000=8,320,000$ total cycles

ii$)$ What is the average CPI for this code?

$8,320,\frac{000}{400},000=20\mathrm{.}8$

iii$)$ How long does it take to execute the code?

$8,320,\frac{000}{2\mathrm{.}5{10}^9}=3\mathrm{.}328{10}^{-6}$ seconds