GATE 2021 · Set-2
Consider the following ANSI C code segment:
z = x + 3 + y→f1 + y→f2;
c
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 dereference operations (of the form y→f1 or y→f2) in the optimized code, respectively, are:
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;
}
}