[llvm] [DebugInfo] Support to get TU for hash from .debug_types.dwo section in DWARF4. (PR #161067)

[Alexander Yermolovich via llvm-commits]

================
@@ -161,17 +161,24 @@ DWARFUnit *DWARFUnitVector::getUnitForOffset(uint64_t Offset) const {
   return nullptr;
 }
 
-DWARFUnit *
-DWARFUnitVector::getUnitForIndexEntry(const DWARFUnitIndex::Entry &E) {
-  const auto *CUOff = E.getContribution(DW_SECT_INFO);
+DWARFUnit *DWARFUnitVector::getUnitForIndexEntry(const DWARFUnitIndex::Entry &E,
+                                                 DWARFSectionKind Sec,
+                                                 const DWARFSection *Section) {
+  const auto *CUOff = E.getContribution(Sec);
   if (!CUOff)
     return nullptr;
 
   uint64_t Offset = CUOff->getOffset();
-  auto end = begin() + getNumInfoUnits();
+  auto begin = this->begin();
+  auto end = begin + getNumInfoUnits();
+
+  if (Sec == DW_SECT_EXT_TYPES) {
+    begin = end;
----------------
ayermolo wrote:

I get that part.
I was wondering about this:
begin = end;
I guess getNumInfoUnits() will return 0 since types are in a separate section for DWARF4. Right?

https://github.com/llvm/llvm-project/pull/161067