[LLVMdev] Questions about trip count
grosser at fim.uni-passau.de
Thu Aug 12 13:22:39 PDT 2010
On 08/12/2010 09:41 PM, Douglas do Couto Teixeira wrote:
> Dear guys,
> I am having problems to obtain good information from the LoopInfo.
> I am always getting a trip count of 0, even though I am clearly passing
> a loop with a constant bound. I am using this pass below:
I would propose to first check if the trip count is calculated
correctly. I would do this with opt by calling:
opt -mem2reg -loopsimplify -indvars -scalar-evolution -analyze prog.ll
At the end of the output the tripcount of every loop should be written.
To get the trip count in your pass you should ask ScalarEvolution.
If you need help trying this please ask back.
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