diff --git a/llvm/lib/CodeGen/ShadowStackGCLowering.cpp b/llvm/lib/CodeGen/ShadowStackGCLowering.cpp
index 1efc440..ff7d205 100644
--- a/llvm/lib/CodeGen/ShadowStackGCLowering.cpp
+++ b/llvm/lib/CodeGen/ShadowStackGCLowering.cpp
@@ -23,6 +23,7 @@
 #include "llvm/IR/IRBuilder.h"
 #include "llvm/IR/IntrinsicInst.h"
 #include "llvm/IR/Module.h"
+#include "llvm/Transforms/Utils/EscapeEnumerator.h"
 
 using namespace llvm;
 
@@ -81,121 +82,6 @@
   initializeShadowStackGCLoweringPass(*PassRegistry::getPassRegistry());
 }
 
-namespace {
-/// EscapeEnumerator - This is a little algorithm to find all escape points
-/// from a function so that "finally"-style code can be inserted. In addition
-/// to finding the existing return and unwind instructions, it also (if
-/// necessary) transforms any call instructions into invokes and sends them to
-/// a landing pad.
-///
-/// It's wrapped up in a state machine using the same transform C# uses for
-/// 'yield return' enumerators, This transform allows it to be non-allocating.
-class EscapeEnumerator {
-  Function &F;
-  const char *CleanupBBName;
-
-  // State.
-  int State;
-  Function::iterator StateBB, StateE;
-  IRBuilder<> Builder;
-
-public:
-  EscapeEnumerator(Function &F, const char *N = "cleanup")
-      : F(F), CleanupBBName(N), State(0), Builder(F.getContext()) {}
-
-  IRBuilder<> *Next() {
-    switch (State) {
-    default:
-      return nullptr;
-
-    case 0:
-      StateBB = F.begin();
-      StateE = F.end();
-      State = 1;
-
-    case 1:
-      // Find all 'return', 'resume', and 'unwind' instructions.
-      while (StateBB != StateE) {
-        BasicBlock *CurBB = &*StateBB++;
-
-        // Branches and invokes do not escape, only unwind, resume, and return
-        // do.
-        TerminatorInst *TI = CurBB->getTerminator();
-        if (!isa<ReturnInst>(TI) && !isa<ResumeInst>(TI))
-          continue;
-
-        Builder.SetInsertPoint(TI);
-        return &Builder;
-      }
-
-      State = 2;
-
-      // Find all 'call' instructions.
-      SmallVector<Instruction *, 16> Calls;
-      for (Function::iterator BB = F.begin(), E = F.end(); BB != E; ++BB)
-        for (BasicBlock::iterator II = BB->begin(), EE = BB->end(); II != EE;
-             ++II)
-          if (CallInst *CI = dyn_cast<CallInst>(II))
-            if (!CI->getCalledFunction() ||
-                !CI->getCalledFunction()->getIntrinsicID())
-              Calls.push_back(CI);
-
-      if (Calls.empty())
-        return nullptr;
-
-      // Create a cleanup block.
-      LLVMContext &C = F.getContext();
-      BasicBlock *CleanupBB = BasicBlock::Create(C, CleanupBBName, &F);
-      Type *ExnTy =
-          StructType::get(Type::getInt8PtrTy(C), Type::getInt32Ty(C), nullptr);
-      if (!F.hasPersonalityFn()) {
-        Constant *PersFn = F.getParent()->getOrInsertFunction(
-            "__gcc_personality_v0",
-            FunctionType::get(Type::getInt32Ty(C), true));
-        F.setPersonalityFn(PersFn);
-      }
-      LandingPadInst *LPad =
-          LandingPadInst::Create(ExnTy, 1, "cleanup.lpad", CleanupBB);
-      LPad->setCleanup(true);
-      ResumeInst *RI = ResumeInst::Create(LPad, CleanupBB);
-
-      // Transform the 'call' instructions into 'invoke's branching to the
-      // cleanup block. Go in reverse order to make prettier BB names.
-      SmallVector<Value *, 16> Args;
-      for (unsigned I = Calls.size(); I != 0;) {
-        CallInst *CI = cast<CallInst>(Calls[--I]);
-
-        // Split the basic block containing the function call.
-        BasicBlock *CallBB = CI->getParent();
-        BasicBlock *NewBB = CallBB->splitBasicBlock(
-            CI->getIterator(), CallBB->getName() + ".cont");
-
-        // Remove the unconditional branch inserted at the end of CallBB.
-        CallBB->getInstList().pop_back();
-        NewBB->getInstList().remove(CI);
-
-        // Create a new invoke instruction.
-        Args.clear();
-        CallSite CS(CI);
-        Args.append(CS.arg_begin(), CS.arg_end());
-
-        InvokeInst *II =
-            InvokeInst::Create(CI->getCalledValue(), NewBB, CleanupBB, Args,
-                               CI->getName(), CallBB);
-        II->setCallingConv(CI->getCallingConv());
-        II->setAttributes(CI->getAttributes());
-        CI->replaceAllUsesWith(II);
-        delete CI;
-      }
-
-      Builder.SetInsertPoint(RI);
-      return &Builder;
-    }
-  }
-};
-}
-
-
 Constant *ShadowStackGCLowering::GetFrameMap(Function &F) {
   // doInitialization creates the abstract type of this value.
   Type *VoidPtr = Type::getInt8PtrTy(F.getContext());