[llvm] [BOLT][DWARF][NFC] Refactor RangeListsWritersByCU (PR #95008)

[Alexander Yermolovich via llvm-commits]

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@@ -1872,9 +1869,8 @@ void DWARFRewriter::updateDWP(DWARFUnit &CU,
 
   DebugRangeListsSectionWriter *RangeListssWriter = nullptr;
   if (CU.getVersion() == 5) {
-    assert(RangeListsWritersByCU.count(DWOId) != 0 &&
-           "No RangeListsWriter for DWO ID.");
-    RangeListssWriter = RangeListsWritersByCU[DWOId].get();
+    assert(RangeListsWriter && "No RangeListsWriter for DWO ID.");
+    RangeListssWriter = RangeListsWriter.get();
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ayermolo wrote:

DWP is now broken because it will use the last one all the time.

https://github.com/llvm/llvm-project/pull/95008