ipa-cp drawback

[charfi asma]

Hello,

I have question concernais the constant propagation drawbacks.
I
red in one of the GCC summit paper that Constant propagation is limited
to create at most one clone of each function body and only in the case:
- the operand is the same constant in all calls to the function 
- the operand would not be propagated without cloning because function might be called externally
This makes the interaction with the inliner suboptimal

Could  so explain more this idea? did this  means that ipa-cp will produce only one version of a calle function? 
Could so  please give me an example that shows this drawbak? 

thank you very much,

Asma