[llvm] [ValueTracking] Fix KnownBits conflict for calls (range vs returned) (PR #84353)

[Nikita Popov via llvm-commits]

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@@ -1476,6 +1476,12 @@ static void computeKnownBitsFromOperator(const Operator *I,
       if (RV->getType() == I->getType()) {
         computeKnownBits(RV, Known2, Depth + 1, Q);
         Known = Known.unionWith(Known2);
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nikic wrote:

The naming of the methods is a bit confusing. This is a union in the sense that we take all the available information from both operands. Not in the sense that we union two ranges.

https://github.com/llvm/llvm-project/pull/84353