[llvm] [ADT] Fix a bug in PackedVector::setValue for signed types (PR #159239)

[Matt Arsenault via llvm-commits]

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@@ -58,6 +58,8 @@ class PackedVectorBase<T, BitNum, BitVectorTy, true> {
     if (val < 0) {
       val = ~val;
       Bits.set((Idx * BitNum) + BitNum - 1);
+    } else {
+      Bits.reset((Idx * BitNum) + BitNum - 1);
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arsenm wrote:

I'd expect signed types to be disallowed? 

https://github.com/llvm/llvm-project/pull/159239