revert r98550, it isn't necessary or sufficient.

llvm-svn: 98558

1 files changed, 3 insertions, 15 deletions

diff --git a/llvm/lib/CodeGen/UnreachableBlockElim.cpp b/llvm/lib/CodeGen/UnreachableBlockElim.cpp
index c0d4494d5b9..7b338126d47 100644
--- a/llvm/lib/CodeGen/UnreachableBlockElim.cpp
+++ b/llvm/lib/CodeGen/UnreachableBlockElim.cpp
@@ -58,25 +58,13 @@ FunctionPass *llvm::createUnreachableBlockEliminationPass() {
   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.
-  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);
+  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 */;
 
   // Loop over all dead blocks, remembering them and deleting all instructions
   // in them.