[PATCH] D30311: [ValueTracking] Don't do an unchecked shift in ComputeNumSignBits

[David Majnemer via Phabricator via llvm-commits]

majnemer accepted this revision.
majnemer added a comment.
This revision is now accepted and ready to land.

LGTM



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Comment at: lib/Analysis/ValueTracking.cpp:2210
+      unsigned ShAmtLimited = ShAmt->getLimitedValue(TyBits);
+      if (ShAmtLimited == TyBits)
+        break;  // Bad shift.
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sanjoy wrote:
> majnemer wrote:
> > Should it be == or >= ?
> The `getLimitedValue` would've taken care about the `>` case.  Though -- I can change it to `getZExtValue()` if you want.
Ah, I see. I think it'd be slightly more clear if we used getZExtValue here.


https://reviews.llvm.org/D30311