[llvm] [DTLTO] [LLVM] Initial DTLTO cache implementation (PR #156433)

[Teresa Johnson via llvm-commits]

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@@ -2326,6 +2336,35 @@ class OutOfProcessThinBackend : public CGThinBackend {
             else
               Err = std::move(E);
           }
+
+          if (Cache.isValid() &&
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teresajohnson wrote:

This lambda is getting pretty large. Can you refactor it into a runThinLTOBackendThread helper, and as much as possible structure it the same way as InProcessThinBackend::runThinLTOBackendThread ? Eventually it may make sense to move some of this into the base CGThinBackend, but at the very least, making the flow similar will help  with comparing the functionality and code maintenance.

https://github.com/llvm/llvm-project/pull/156433