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.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@142572 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Transforms/IPO/Inliner.cpp b/lib/Transforms/IPO/Inliner.cpp
index f00935b..bdc9fe4 100644
--- a/lib/Transforms/IPO/Inliner.cpp
+++ b/lib/Transforms/IPO/Inliner.cpp
@@ -533,10 +533,7 @@
if (DNR && DNR->count(F))
continue;
- if (!F->hasLinkOnceLinkage() && !F->hasLocalLinkage() &&
- !F->hasAvailableExternallyLinkage())
- continue;
- if (!F->use_empty())
+ if (!F->isDefTriviallyDead())
continue;
// Remove any call graph edges from the function to its callees.