[llvm] [BOLT][DWARF][NFC] Split DIEBuilder::finish (PR #101244)

[Alexander Yermolovich via llvm-commits]

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@@ -535,11 +523,12 @@ void DIEBuilder::finish() {
     finalizeCU(*CU, TypeUnitStartOffset);
   }
 
+  uint64_t UnitSizes = UnitSize;
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ayermolo wrote:

Let's just separate this into two variables.
One for computing CU offsets here, and another one for DebugNamesTable.
I think this kind of fragile to rely on updateDebugNamesTable to update UnitSize and to make sure for monolithic case it's invoked right after finish()

https://github.com/llvm/llvm-project/pull/101244