[llvm] [BOLT][DWARF] Refactor legacy ranges writers (PR #96006)

[Alexander Yermolovich via llvm-commits]

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@@ -1320,15 +1326,18 @@ void DWARFRewriter::updateDWARFObjectAddressRanges(
 
     // If we are at this point we are in the CU/Skeleton CU, and
     // DW_AT_GNU_ranges_base or DW_AT_rnglists_base doesn't exist.
-    if (Unit.getVersion() <= 4)
+    if (Unit.getVersion() <= 4) {
       DIEBldr.addValue(&Die, dwarf::DW_AT_GNU_ranges_base, dwarf::DW_FORM_data4,
-                       DIEInteger(*RangesBase));
-    else if (Unit.getVersion() == 5)
+                       DIEInteger(INT_MAX));
+      LegacyRangesWritersByCU[*Unit.getDWOId()]->setDie(
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ayermolo wrote:

I wonder that since this will be multi threaded, it's better to use find. [] Can write. Although in this particular case it should be read only.

https://github.com/llvm/llvm-project/pull/96006