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Re: -funsafe-loop-optimizations




On Sat, 1 Jan 2005, Steven Bosscher wrote:

Is it maybe possible in some cases to look at how the induction
variable is used (e.g. as an array index and we know that it is
undefined to have an index outside the array domain), and decide
on whether the loop must be finite or not based on that?


We take this into account in estimating the number of iterations.


This is one of the reasons we can interchange swim.

The only possible dependence occurs in an iteration that would be past the end of the array it's accessing, so we assume this dependence doesn't matter.




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