[llvm] [BOLT][DWARF][NFC] Change how we re-size CloneUnitCtxMap (PR #75876)

[Amir Ayupov via llvm-commits]

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@@ -897,6 +897,8 @@ void DIEBuilder::registerUnit(DWARFUnit &DU, bool NeedSort) {
                 });
   }
   getState().UnitIDMap[getHash(DU)] = getState().DUList.size();
+  if (getState().DUList.size() == getState().CloneUnitCtxMap.size())
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aaupov wrote:

Please add a comment why this condition is the one for allocating a new CloneUnitCtxMap entry.

https://github.com/llvm/llvm-project/pull/75876