GATE | GATE CS 2008 | Question 85
Some code optimizations are carried out on the intermediate code because
(A) they enhance the portability of the compiler to other target processors
(B) program analysis is more accurate on intermediate code than on machine code
(C) the information from dataflow analysis cannot otherwise be used for optimization
(D) the information from the front end cannot otherwise be used for optimization
Explanation: Option (B) is also true. But the main purpose of doing some code-optimization on intermediate code generation is to enhance the portability of the compiler to target processors. So Option A) is more suitable here.
Intermediate code is machine/architecture independent code. So a compiler can optimize it without worrying about the architecture on which the code is going to execute (it may be the same or the other ). So that kind of compiler can be used by multiple different architectures.
In contrast to that, suppose code optimization is done on target code, which is machine/architecture dependent, then the compiler has be specific about the optimizations on that kind of code. In this case the compiler can’t be used by multiple different architectures, because the target code produced on different architectures would be different. Hence portability reduces here.