[llvm] [LLVM][DWARF] Add support for monolithic types in .debug_names (PR #68131)

[Alexander Yermolovich via llvm-commits]

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@@ -3514,11 +3520,15 @@ void DwarfDebug::addDwarfTypeUnitType(DwarfCompileUnit &CU,
       return;
     }
 
-    // If the type wasn't dependent on fission addresses, finish adding the type
-    // and all its dependent types.
     for (auto &TU : TypeUnitsToAdd) {
       InfoHolder.computeSizeAndOffsetsForUnit(TU.first.get());
       InfoHolder.emitUnit(TU.first.get(), useSplitDwarf());
+      if (getDwarfVersion() >= 5 &&
+          getAccelTableKind() == AccelTableKind::Dwarf) {
+        addTypeUnit(std::move(TU.first));
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ayermolo wrote:

> > I have not. Were you thinking for one invocation of clang, or to build whole project?
> > What do you think a reasonable number of type units pre compilation modules are?
> 
> Given I expect this to be a fairly clear non-starter, I'd probably test something pretty simple like, say, Clang's Sema.cpp - it's a bit of a big/rough thing to compile, probably has enough types to show up a significant regression I'd expect would be caused by keeping all the TUs alive to the end of the compilation.

ok, let me do some memory overhead testing, and also seperate this in to two changes.

https://github.com/llvm/llvm-project/pull/68131