[llvm] [DemandedBits] Support non-constant shift amounts (PR #148880)

[Yingwei Zheng via llvm-commits]

================
@@ -76,6 +76,16 @@ void DemandedBits::determineLiveOperandBits(
           computeKnownBits(V2, Known2, DL, &AC, UserI, &DT);
         }
       };
+  auto GetShiftedRange = [&](unsigned const Min, unsigned const Max,
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dtcxzyw wrote:

```suggestion
  auto GetShiftedRange = [&](unsigned Min, unsigned Max,
```

https://github.com/llvm/llvm-project/pull/148880