1 files changed, 13 insertions, 0 deletions
diff --git a/llvm/lib/Transforms/IPO/MergeFunctions.cpp b/llvm/lib/Transforms/IPO/MergeFunctions.cpp
index c19cf71..c8c011d 100644
--- a/llvm/lib/Transforms/IPO/MergeFunctions.cpp
+++ b/llvm/lib/Transforms/IPO/MergeFunctions.cpp
@@ -662,6 +662,13 @@ static bool canCreateThunkFor(Function *F) {
   return true;
 }
 
+/// Copy metadata from one function to another.
+static void copyMetadataIfPresent(Function *From, Function *To, StringRef Key) {
+  if (MDNode *MD = From->getMetadata(Key)) {
+    To->setMetadata(Key, MD);
+  }
+}
+
 // Replace G with a simple tail call to bitcast(F). Also (unless
 // MergeFunctionsPDI holds) replace direct uses of G with bitcast(F),
 // delete G. Under MergeFunctionsPDI, we use G itself for creating
@@ -740,6 +747,9 @@ void MergeFunctions::writeThunk(Function *F, Function *G) {
   } else {
     NewG->copyAttributesFrom(G);
     NewG->takeName(G);
+    // Ensure CFI type metadata is propagated to the new function.
+    copyMetadataIfPresent(G, NewG, "type");
+    copyMetadataIfPresent(G, NewG, "kcfi_type");
     removeUsers(G);
     G->replaceAllUsesWith(NewG);
     G->eraseFromParent();
@@ -815,6 +825,9 @@ void MergeFunctions::mergeTwoFunctions(Function *F, Function *G) {
                                       F->getAddressSpace(), "", F->getParent());
     NewF->copyAttributesFrom(F);
     NewF->takeName(F);
+    // Ensure CFI type metadata is propagated to the new function.
+    copyMetadataIfPresent(F, NewF, "type");
+    copyMetadataIfPresent(F, NewF, "kcfi_type");
     removeUsers(F);
     F->replaceAllUsesWith(NewF);