6.2.5 For-Loop Level

The following qualifiers set a minimum for -loop nest level for function call expansion. The /inline_ looplevel and /ipa_looplevel qualifiers enable you to limit inlining and IPA to just functions that are referenced in nested loops, where the reduced function call overhead or enhanced optimization will be multiplied:

/inline_looplevel=<n>  [/inll]
/ipa_looplevel=<n>     [/ipall]

The argument is defined from the most deeply nested leaf of the call tree. A small value restricts inlining (IPA) to the best candidate functions, for example:

main
{
..
  a(); ------>  a() {...}
    }

 ..
 for (..) {
   for (..) {
     b(); --------->  b() {
     }        for (..) {
 }         for (..) {
      c(); -------> c() {...}
             }
              }
        }

The call to b is inside a doubly nested loop, and would be more profitable to expand than the call to a . The call to c is quadruply nested, so inlining c would yield the biggest gain of the three.

The argument is defined from the most deeply nested function reference:


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