[LLVMdev] Dependence Analysis [was: Flow-Sensitive AA]

John Regehr regehr at cs.utah.edu
Fri Aug 22 20:18:20 PDT 2008


> before and it hurts about 3-5 without high level loop
> opts/vectorization on.  With them on, they do roughly nothing in the
> presence of -fwrapv because you can't determine bounds of any non
> trivial loop.

Very interesting, thanks!  Before hearing this I'd have said that 
Java-style overflow is the right language design, but if this makes loop 
optimizations impossible that is not so good.

John



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