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Q. Consider the following ANSI C code segment:
Assume that the variable y points to a struct (allocated on the heap) containing two fields f1 and f2, and the local variables x, y, z, p, q, and i are allotted registers. Common sub-expression elimination (CSE) optimization is applied on the code. The number of addition and the dereference operations (of the form y ->f1 or y ->f2) in the optimized code, respectively, are:

Code:

z=x + 3 + y->f1 + y->f2;
for (i = 0; i < 200; i = i + 2)
{
if (z > i)
{
p = p + x + 3;
q = q + y->f1;
} else
{
p = p + y->f2;
q = q + x + 3;
}
}

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