[CallGraphUpdater] Remove dead constants before replacing a function

Dead constants might be left when a function is replaced, we can
gracefully handle this case and avoid complexity for the users who would
see an assertion otherwise.

1 files changed, 1 insertions, 0 deletions

diff --git a/llvm/lib/Transforms/Utils/CallGraphUpdater.cpp b/llvm/lib/Transforms/Utils/CallGraphUpdater.cpp
index a7a214d..4de7124 100644
--- a/llvm/lib/Transforms/Utils/CallGraphUpdater.cpp
+++ b/llvm/lib/Transforms/Utils/CallGraphUpdater.cpp
@@ -106,6 +106,7 @@ void CallGraphUpdater::removeFunction(Function &DeadFn) {
 }
 
 void CallGraphUpdater::replaceFunctionWith(Function &OldFn, Function &NewFn) {
+  OldFn.removeDeadConstantUsers();
   ReplacedFunctions.insert(&OldFn);
   if (CG) {
     // Update the call graph for the newly promoted function.