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diff --git a/contrib/llvm/lib/Transforms/ObjCARC/ObjCARC.h b/contrib/llvm/lib/Transforms/ObjCARC/ObjCARC.h
new file mode 100644
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+++ b/contrib/llvm/lib/Transforms/ObjCARC/ObjCARC.h
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+//===- ObjCARC.h - ObjC ARC Optimization --------------*- C++ -*-----------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+/// \file
+/// This file defines common definitions/declarations used by the ObjC ARC
+/// Optimizer. ARC stands for Automatic Reference Counting and is a system for
+/// managing reference counts for objects in Objective C.
+///
+/// WARNING: This file knows about certain library functions. It recognizes them
+/// by name, and hardwires knowledge of their semantics.
+///
+/// WARNING: This file knows about how certain Objective-C library functions are
+/// used. Naive LLVM IR transformations which would otherwise be
+/// behavior-preserving may break these assumptions.
+///
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_LIB_TRANSFORMS_OBJCARC_OBJCARC_H
+#define LLVM_LIB_TRANSFORMS_OBJCARC_OBJCARC_H
+
+#include "llvm/ADT/StringSwitch.h"
+#include "llvm/ADT/Optional.h"
+#include "llvm/Analysis/AliasAnalysis.h"
+#include "llvm/Analysis/ObjCARCAnalysisUtils.h"
+#include "llvm/Analysis/ObjCARCInstKind.h"
+#include "llvm/Analysis/Passes.h"
+#include "llvm/Analysis/ValueTracking.h"
+#include "llvm/IR/CallSite.h"
+#include "llvm/IR/InstIterator.h"
+#include "llvm/IR/Module.h"
+#include "llvm/Pass.h"
+#include "llvm/Transforms/ObjCARC.h"
+#include "llvm/Transforms/Utils/Local.h"
+
+namespace llvm {
+class raw_ostream;
+}
+
+namespace llvm {
+namespace objcarc {
+
+/// \brief Erase the given instruction.
+///
+/// Many ObjC calls return their argument verbatim,
+/// so if it's such a call and the return value has users, replace them with the
+/// argument value.
+///
+static inline void EraseInstruction(Instruction *CI) {
+  Value *OldArg = cast<CallInst>(CI)->getArgOperand(0);
+
+  bool Unused = CI->use_empty();
+
+  if (!Unused) {
+    // Replace the return value with the argument.
+    assert((IsForwarding(GetBasicARCInstKind(CI)) ||
+            (IsNoopOnNull(GetBasicARCInstKind(CI)) &&
+             isa<ConstantPointerNull>(OldArg))) &&
+           "Can't delete non-forwarding instruction with users!");
+    CI->replaceAllUsesWith(OldArg);
+  }
+
+  CI->eraseFromParent();
+
+  if (Unused)
+    RecursivelyDeleteTriviallyDeadInstructions(OldArg);
+}
+
+} // end namespace objcarc
+} // end namespace llvm
+
+#endif