[PATCH] D29808: WholeProgramDevirt: Add any unsuccessful llvm.type.checked.load devirtualizations to the list of llvm.type.test users.

[Mehdi AMINI via Phabricator via llvm-commits]

mehdi_amini added inline comments.


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Comment at: llvm/lib/Transforms/IPO/WholeProgramDevirt.cpp:1045
 
+  if (Action == PassSummaryAction::Export) {
+    DenseMap<GlobalValue::GUID, TinyPtrVector<Metadata *>> MetadataByGUID;
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Might be worth adding a one line comment to describe this block


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Comment at: llvm/lib/Transforms/IPO/WholeProgramDevirt.cpp:1095
+    // devirtualized, we need to add the resulting llvm.type.test intrinsics to
+    // the function summaries so that the LowerTypeTests pass will export them.
+    if (Action == PassSummaryAction::Export && isa<MDString>(S.first.TypeID)) {
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I'm still not sure what/why this is done. What happens in which phase? 
What is the LowerTypeTests pass exporting exactly, and for which consumer?


https://reviews.llvm.org/D29808