[LLVMdev] Possible bug in ExpandShiftWithUnknownAmountBit

Duncan Sands baldrick at free.fr
Fri Dec 4 23:30:59 PST 2009

Hi Javier,

> I don't know if the optimization would help us much. Our architecture
> performs integer shifts and subtractions at the same speed. I think the
> optimization is limited to the case where NVBits is a power of two.

it is irrelevant whether it is a power of two or not.  Anyway, since you
are the only user, and this is not helpful for you, I guess we can forget
it :)

> In your previous email you mentioned some comments added to check-in 90564.
> In our architecture shifting by 0 doesn't cause any problems but the
> comment might be valid for others.

Actually it's the shifting by 32 (if NVBits is 32) which is a problem.
If Amt is zero then a shift by 32 is generated at commented line.



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