GATE 2013 · session-1
The following code is executed on a processor allowing only register operands. Each instruction can have at most two source operands and one destination operand. Assume all variables are dead after this code segment.
c = a + b;
d = c * a;
e = c + a;
x = c * c;
c
What is the minimum number of registers needed to compile this code segment without any spill to memory? Do not apply any optimization other than optimizing register allocation.
if (x > a) {
y = a * a;
}
else {
d = d * d;
e = e * e;
}