1 files changed, 15 insertions, 0 deletions
diff --git a/include/llvm/ADT/ilist.h b/include/llvm/ADT/ilist.h
index 7f5cd17181..20cdae3255 100644
--- a/include/llvm/ADT/ilist.h
+++ b/include/llvm/ADT/ilist.h
@@ -465,6 +465,17 @@ public:
     return where;
   }
 
+  /// Remove all nodes from the list like clear(), but do not call
+  /// removeNodeFromList() or deleteNode().
+  ///
+  /// This should only be used immediately before freeing nodes in bulk to
+  /// avoid traversing the list and bringing all the nodes into cache.
+  void clearAndLeakNodesUnsafely() {
+    if (Head) {
+      Head = getTail();
+      this->setPrev(Head, Head);
+    }
+  }
 
 private:
   // transfer - The heart of the splice function.  Move linked list nodes from
@@ -472,6 +483,10 @@ private:
   //
   void transfer(iterator position, iplist &L2, iterator first, iterator last) {
     assert(first != last && "Should be checked by callers");
+    // Position cannot be contained in the range to be transferred.
+    // Check for the most common mistake.
+    assert(position != first &&
+           "Insertion point can't be one of the transferred nodes");
 
     if (position != last) {
       // Note: we have to be careful about the case when we move the first node