linux-arm-g++

["rkthebad"]

Group,
I am compiling a code written for ARM on the linux-arm-g++ compiler. I
have built other codes before but have always observed that -O3
produces almost the same efficient code as -O2, if not better.

Strangely, I observe that for this code, the compiler option -O2
produces an efficient code (fewer cycles) than that obtained using -O3.


Why the strange behaviour? I did check the output in both the cases,
and they match.

Thanks in advance,
~RK