Refactor code from inlining and globalopt that checks whether a function definition is unused, and enhance it so it can tell that functions which are only used by a blockaddress are in fact dead. This probably doesn't happen much on most code, but the Linux kernel's _THIS_IP_ can trigger this issue with blockaddress. (GlobalDCE can also handle the given tescase, but we only run that at -O3.) Found while looking at PR11180.

llvm-svn: 142572

1 files changed, 2 insertions, 2 deletions

diff --git a/llvm/lib/Transforms/Utils/BasicInliner.cpp b/llvm/lib/Transforms/Utils/BasicInliner.cpp
index 23a30cc5850..50c91b6af87 100644
--- a/llvm/lib/Transforms/Utils/BasicInliner.cpp
+++ b/llvm/lib/Transforms/Utils/BasicInliner.cpp
@@ -131,8 +131,8 @@ void BasicInlinerImpl::inlineFunctions() {
         // Inline
         InlineFunctionInfo IFI(0, TD);
         if (InlineFunction(CS, IFI)) {
-          if (Callee->use_empty() && (Callee->hasLocalLinkage() ||
-                                      Callee->hasAvailableExternallyLinkage()))
+          Callee->removeDeadConstantUsers();
+          if (Callee->isDefTriviallyDead())
             DeadFunctions.insert(Callee);
           Changed = true;
           CallSites.erase(CallSites.begin() + index);