[PATCH] D28393: [SCEV] Make howFarToZero produce a smaller max backedge-taken count

[Sanjoy Das via Phabricator via llvm-commits]

sanjoy added inline comments.


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Comment at: lib/Analysis/ScalarEvolution.cpp:7219
+      ConstantRange CR = getUnsignedRange(DistancePlusOne);
+      APInt NewMaxBECount = CR.getUnsignedMax() - One->getAPInt();
+      if (NewMaxBECount.ult(MaxBECount))
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sanjoy wrote:
> Why are you checking `(Distance + 1) != 0` instead of `Distance != -1`?  I'd find the latter more straightforward.
In case I gave the wrong impression, I don't specifically care about checking `(Distance + 1) != 0` vs. `Distance != -1`.  If you find the former more straightforward, then I'm okay too.


https://reviews.llvm.org/D28393