Assume you have the following codevoid inner$4($vec$\_$ptr u$,$ vec$\_$ptr v$,$ data$\_$t $*$dest$)$

$\{$int length $=$ vec$\_$length$($u$)$;data$\_$t $*$vdata $=$ get$\_$vec$\_$start$($v$)$;for $($i $=0$; i $$ length; i$++)\{\}$

$*$dest $=$ sum;

$\}$and you modify the code to use $4-$way loop unrolling and four parallel accumulators. Measurements for this function with the x$86-$

$64$ architecture shows it achieves a CPE of $2\mathrm{.}0$ for all types of data.

Assuming the model of the Intel i$7$ architecture shown in class $($one branch unit, two arithmetic units, one load and one store unit$),$

the performance of this loop with any arithmetic operation can not get below $2\mathrm{.}0$ CPE because of

When the same $44$ code is compiled for the IA$32$ architecture, it achieves a CPE of $2\mathrm{.}75,$ worse than the CPE of $2\mathrm{.}25$ achieved

with just four$-$way unrolling. The mostly likely reason this occurs is because