[LLVMdev] getSmallConstantTripCount problem

Duncan Sands baldrick at free.fr
Thu Apr 28 07:13:13 PDT 2011

Hi Bo,

> In my pass, I add LoopInfo as a required pass. Then I'd like to print the
> constant loop trip count of each loop if it has one. However, every time I call
> loop->
> getSmallConstantTripCount(), it returns 0, even for a very simple loop: for(i=0;
> i<3; ++i) {;}  What's the possible cause of this problem?

this comes up regularly, so search the mailing list archives.  IIRC, you need to
run some other passes first: mem2reg and probably some others I forget.

Ciao, Duncan.

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