diff --git a/lib/CodeGen/CGStmt.cpp b/lib/CodeGen/CGStmt.cpp
index a66b6fe..ad081c9 100644
--- a/lib/CodeGen/CGStmt.cpp
+++ b/lib/CodeGen/CGStmt.cpp
@@ -157,9 +157,15 @@
   return EmitAnyExpr(cast<Expr>(LastStmt), AggLoc);
 }
 
-void CodeGenFunction::EmitBlock(llvm::BasicBlock *BB) {
+void CodeGenFunction::EmitBlock(llvm::BasicBlock *BB, bool IsFinished) {
   // Fall out of the current block (if necessary).
   EmitBranch(BB);
+
+  if (IsFinished && BB->use_empty()) {
+    delete BB;
+    return;
+  }
+
   CurFn->getBasicBlockList().push_back(BB);
   Builder.SetInsertPoint(BB);
 }
diff --git a/lib/CodeGen/CodeGenFunction.h b/lib/CodeGen/CodeGenFunction.h
index 21d8f4f..50b35bd 100644
--- a/lib/CodeGen/CodeGenFunction.h
+++ b/lib/CodeGen/CodeGenFunction.h
@@ -237,7 +237,12 @@
   /// insert point, adding a fall-through branch from the current
   /// insert block if necessary. It is legal to call this function
   /// even if there is no current insertion point.
-  void EmitBlock(llvm::BasicBlock *BB);
+  ///
+  /// IsFinished - If true, indicates that the caller has finished
+  /// emitting branches to the given block and does not expect to emit
+  /// code into it. This means the block can be ignored if it is
+  /// unreachable.
+  void EmitBlock(llvm::BasicBlock *BB, bool IsFinished=false);
 
   /// EmitBranch - Emit a branch to the specified basic block from the
   /// current insert block, taking care to avoid creation of branches