Index: llvm/trunk/include/llvm/Transforms/IPO/Attributor.h
===================================================================
--- llvm/trunk/include/llvm/Transforms/IPO/Attributor.h
+++ llvm/trunk/include/llvm/Transforms/IPO/Attributor.h
@@ -675,6 +675,15 @@
   void identifyDefaultAbstractAttributes(
       Function &F, DenseSet<const char *> *Whitelist = nullptr);
 
+  /// Record that \p I is deleted after information was manifested.
+  void deleteAfterManifest(Instruction &I) { ToBeDeletedInsts.insert(&I); }
+
+  /// Record that \p BB is deleted after information was manifested.
+  void deleteAfterManifest(BasicBlock &BB) { ToBeDeletedBlocks.insert(&BB); }
+
+  /// Record that \p F is deleted after information was manifested.
+  void deleteAfterManifest(Function &F) { ToBeDeletedFunctions.insert(&F); }
+
   /// Return true if \p AA (or its context instruction) is assumed dead.
   ///
   /// If \p LivenessAA is not provided it is queried.
@@ -765,6 +774,14 @@
 
   /// The information cache that holds pre-processed (LLVM-IR) information.
   InformationCache &InfoCache;
+
+  /// Functions, blocks, and instructions we delete after manifest is done.
+  ///
+  ///{
+  SmallPtrSet<Function *, 8> ToBeDeletedFunctions;
+  SmallPtrSet<BasicBlock *, 8> ToBeDeletedBlocks;
+  SmallPtrSet<Instruction *, 8> ToBeDeletedInsts;
+  ///}
 };
 
 /// An interface to query the internal state of an abstract attribute.
Index: llvm/trunk/lib/Transforms/IPO/Attributor.cpp
===================================================================
--- llvm/trunk/lib/Transforms/IPO/Attributor.cpp
+++ llvm/trunk/lib/Transforms/IPO/Attributor.cpp
@@ -2641,6 +2641,26 @@
   assert(
       NumFinalAAs == AllAbstractAttributes.size() &&
       "Expected the final number of abstract attributes to remain unchanged!");
+
+  // Delete stuff at the end to avoid invalid references and a nice order.
+  LLVM_DEBUG(dbgs() << "\n[Attributor] Delete " << ToBeDeletedFunctions.size()
+                    << " functions and " << ToBeDeletedBlocks.size()
+                    << " blocks and " << ToBeDeletedInsts.size()
+                    << " instructions\n");
+  for (Instruction *I : ToBeDeletedInsts) {
+    if (I->hasNUsesOrMore(1))
+      I->replaceAllUsesWith(UndefValue::get(I->getType()));
+    I->eraseFromParent();
+  }
+  for (BasicBlock *BB : ToBeDeletedBlocks) {
+    // TODO: Check if we need to replace users (PHIs, indirect branches?)
+    BB->eraseFromParent();
+  }
+  for (Function *Fn : ToBeDeletedFunctions) {
+    Fn->replaceAllUsesWith(UndefValue::get(Fn->getType()));
+    Fn->eraseFromParent();
+  }
+
   return ManifestChange;
 }