don't eliminate address-taken blocks here.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@98550 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/UnreachableBlockElim.cpp b/lib/CodeGen/UnreachableBlockElim.cpp
index 7b33812..c0d4494 100644
--- a/lib/CodeGen/UnreachableBlockElim.cpp
+++ b/lib/CodeGen/UnreachableBlockElim.cpp
@@ -58,13 +58,25 @@
return new UnreachableBlockElim();
}
+static void MarkReachableFrom(BasicBlock *BB,
+ SmallPtrSet<BasicBlock*, 8> &Reachable) {
+ for (df_ext_iterator<BasicBlock*, SmallPtrSet<BasicBlock*, 8> > I =
+ df_ext_begin(BB, Reachable), E = df_ext_end(BB, Reachable); I != E; ++I)
+ ; // Mark all reachable blocks.
+}
+
bool UnreachableBlockElim::runOnFunction(Function &F) {
SmallPtrSet<BasicBlock*, 8> Reachable;
// Mark all reachable blocks.
- for (df_ext_iterator<Function*, SmallPtrSet<BasicBlock*, 8> > I =
- df_ext_begin(&F, Reachable), E = df_ext_end(&F, Reachable); I != E; ++I)
- /* Mark all reachable blocks */;
+ MarkReachableFrom(&F.getEntryBlock(), Reachable);
+
+ // Mark any address-taken blocks. We don't want codegen to delete these
+ // because the address may already be referenced by another function and the
+ // label may be referenced.
+ for (Function::iterator I = F.begin(), E = F.end(); I != E; ++I)
+ if (I->hasAddressTaken() && !Reachable.count(I))
+ MarkReachableFrom(I, Reachable);
// Loop over all dead blocks, remembering them and deleting all instructions
// in them.