[llvm] [BOLT][DWARF][NFC] Split processUnitDIE into two lambdas (PR #99225)

[Sayhaan Siddiqui via llvm-commits]

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@@ -621,119 +621,122 @@ void DWARFRewriter::updateDebugInfo() {
   std::mutex AccessMutex;
   // Needs to be invoked in the same order as CUs are processed.
   auto createRangeLocListAddressWriters =
-      [&](DWARFUnit &CU) -> DebugLocWriter * {
-    std::lock_guard<std::mutex> Lock(AccessMutex);
-    const uint16_t DwarfVersion = CU.getVersion();
-    if (DwarfVersion >= 5) {
-      auto AddrW = std::make_unique<DebugAddrWriterDwarf5>(
-          &BC, CU.getAddressByteSize(), CU.getAddrOffsetSectionBase());
-      RangeListsSectionWriter->setAddressWriter(AddrW.get());
-      LocListWritersByCU[CUIndex] =
-          std::make_unique<DebugLoclistWriter>(CU, DwarfVersion, false, *AddrW);
-
-      if (std::optional<uint64_t> DWOId = CU.getDWOId()) {
-        assert(RangeListsWritersByCU.count(*DWOId) == 0 &&
-               "RangeLists writer for DWO unit already exists.");
-        auto DWORangeListsSectionWriter =
-            std::make_unique<DebugRangeListsSectionWriter>();
-        DWORangeListsSectionWriter->initSection(CU);
-        DWORangeListsSectionWriter->setAddressWriter(AddrW.get());
-        RangeListsWritersByCU[*DWOId] = std::move(DWORangeListsSectionWriter);
-      }
-      AddressWritersByCU[CU.getOffset()] = std::move(AddrW);
+      [&](DWARFUnit &CU,
+          llvm::DenseMap<uint64_t, uint64_t> &LocListWritersIndexByCU) {
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sayhaan wrote:

For LocListWritersIndexByCU? It wouldn't be in scope for the lambda to capture by reference since I initialize it inside the for loop. I could move it outside but then its lifetime is longer than it needs to be since it's only used in the lambda.

https://github.com/llvm/llvm-project/pull/99225