Controls the level of optimization performed by the compiler.
LEVEL=0 is the same as /NOOPTIMIZE and suppresses all optional optimizations.
LEVEL=3 is the default optimization level and provides all optional optimizations except memory blocking.
LEVEL=4 provides all optimizations including memory blocking, which can improve performance for non-vectorized applications which operate on large arrays. See the performance guide for more details. LEVEL=4 cannot be specified if /CHECK=BOUNDS is in effect.