[PATCH] D70006: [ThinLTO] Fix bug when importing writeonly variables

[Teresa Johnson via Phabricator via llvm-commits]

tejohnson accepted this revision.
tejohnson added a comment.
This revision is now accepted and ready to land.

Let's get this one in (I have a couple more comment nits below), to fix the immediate problem. But please send a follow on patch soon to do the assertion checking I suggested in my earlier comment, to make sure we catch any regressions to the force import of these write only variables.



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Comment at: llvm/lib/IR/ModuleSummaryIndex.cpp:204
+    // Definition of writeonly GV with non-trivial initializer should also
+    // be imported. Not doing so will result in:
+    // a) GV internalization in source module (because it's writeonly)
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Add that this is because we don't AnalyzeRefs when propagating the write only property.


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Comment at: llvm/lib/Transforms/Utils/FunctionImportUtils.cpp:260
+        // promoted, because there is no any kind of read access to them
+        // on behalf of this writeonly GV. To avoid promotion we convert
+        // GV initializer to 'zeroinitializer'. This effectively drops
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Please add that this is because we do not export their references.


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https://reviews.llvm.org/D70006