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diff --git a/contrib/llvm/lib/Analysis/ObjCARCAliasAnalysis.cpp b/contrib/llvm/lib/Analysis/ObjCARCAliasAnalysis.cpp
new file mode 100644
index 000000000000..25f660ffe221
--- /dev/null
+++ b/contrib/llvm/lib/Analysis/ObjCARCAliasAnalysis.cpp
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+//===- ObjCARCAliasAnalysis.cpp - ObjC ARC Optimization -------------------===//
+//
+//                     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 a simple ARC-aware AliasAnalysis using special knowledge
+/// of Objective C to enhance other optimization passes which rely on the Alias
+/// Analysis infrastructure.
+///
+/// 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.
+///
+/// TODO: Theoretically we could check for dependencies between objc_* calls
+/// and FMRB_OnlyAccessesArgumentPointees calls or other well-behaved calls.
+///
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Analysis/ObjCARCAliasAnalysis.h"
+#include "llvm/Analysis/ObjCARCAnalysisUtils.h"
+#include "llvm/IR/Function.h"
+#include "llvm/IR/Instruction.h"
+#include "llvm/IR/Value.h"
+#include "llvm/InitializePasses.h"
+#include "llvm/PassAnalysisSupport.h"
+#include "llvm/PassSupport.h"
+
+#define DEBUG_TYPE "objc-arc-aa"
+
+using namespace llvm;
+using namespace llvm::objcarc;
+
+AliasResult ObjCARCAAResult::alias(const MemoryLocation &LocA,
+                                   const MemoryLocation &LocB) {
+  if (!EnableARCOpts)
+    return AAResultBase::alias(LocA, LocB);
+
+  // First, strip off no-ops, including ObjC-specific no-ops, and try making a
+  // precise alias query.
+  const Value *SA = GetRCIdentityRoot(LocA.Ptr);
+  const Value *SB = GetRCIdentityRoot(LocB.Ptr);
+  AliasResult Result =
+      AAResultBase::alias(MemoryLocation(SA, LocA.Size, LocA.AATags),
+                          MemoryLocation(SB, LocB.Size, LocB.AATags));
+  if (Result != MayAlias)
+    return Result;
+
+  // If that failed, climb to the underlying object, including climbing through
+  // ObjC-specific no-ops, and try making an imprecise alias query.
+  const Value *UA = GetUnderlyingObjCPtr(SA, DL);
+  const Value *UB = GetUnderlyingObjCPtr(SB, DL);
+  if (UA != SA || UB != SB) {
+    Result = AAResultBase::alias(MemoryLocation(UA), MemoryLocation(UB));
+    // We can't use MustAlias or PartialAlias results here because
+    // GetUnderlyingObjCPtr may return an offsetted pointer value.
+    if (Result == NoAlias)
+      return NoAlias;
+  }
+
+  // If that failed, fail. We don't need to chain here, since that's covered
+  // by the earlier precise query.
+  return MayAlias;
+}
+
+bool ObjCARCAAResult::pointsToConstantMemory(const MemoryLocation &Loc,
+                                             bool OrLocal) {
+  if (!EnableARCOpts)
+    return AAResultBase::pointsToConstantMemory(Loc, OrLocal);
+
+  // First, strip off no-ops, including ObjC-specific no-ops, and try making
+  // a precise alias query.
+  const Value *S = GetRCIdentityRoot(Loc.Ptr);
+  if (AAResultBase::pointsToConstantMemory(
+          MemoryLocation(S, Loc.Size, Loc.AATags), OrLocal))
+    return true;
+
+  // If that failed, climb to the underlying object, including climbing through
+  // ObjC-specific no-ops, and try making an imprecise alias query.
+  const Value *U = GetUnderlyingObjCPtr(S, DL);
+  if (U != S)
+    return AAResultBase::pointsToConstantMemory(MemoryLocation(U), OrLocal);
+
+  // If that failed, fail. We don't need to chain here, since that's covered
+  // by the earlier precise query.
+  return false;
+}
+
+FunctionModRefBehavior ObjCARCAAResult::getModRefBehavior(const Function *F) {
+  if (!EnableARCOpts)
+    return AAResultBase::getModRefBehavior(F);
+
+  switch (GetFunctionClass(F)) {
+  case ARCInstKind::NoopCast:
+    return FMRB_DoesNotAccessMemory;
+  default:
+    break;
+  }
+
+  return AAResultBase::getModRefBehavior(F);
+}
+
+ModRefInfo ObjCARCAAResult::getModRefInfo(ImmutableCallSite CS,
+                                          const MemoryLocation &Loc) {
+  if (!EnableARCOpts)
+    return AAResultBase::getModRefInfo(CS, Loc);
+
+  switch (GetBasicARCInstKind(CS.getInstruction())) {
+  case ARCInstKind::Retain:
+  case ARCInstKind::RetainRV:
+  case ARCInstKind::Autorelease:
+  case ARCInstKind::AutoreleaseRV:
+  case ARCInstKind::NoopCast:
+  case ARCInstKind::AutoreleasepoolPush:
+  case ARCInstKind::FusedRetainAutorelease:
+  case ARCInstKind::FusedRetainAutoreleaseRV:
+    // These functions don't access any memory visible to the compiler.
+    // Note that this doesn't include objc_retainBlock, because it updates
+    // pointers when it copies block data.
+    return MRI_NoModRef;
+  default:
+    break;
+  }
+
+  return AAResultBase::getModRefInfo(CS, Loc);
+}
+
+ObjCARCAAResult ObjCARCAA::run(Function &F, AnalysisManager<Function> *AM) {
+  return ObjCARCAAResult(F.getParent()->getDataLayout(),
+                         AM->getResult<TargetLibraryAnalysis>(F));
+}
+
+char ObjCARCAA::PassID;
+
+char ObjCARCAAWrapperPass::ID = 0;
+INITIALIZE_PASS_BEGIN(ObjCARCAAWrapperPass, "objc-arc-aa",
+                      "ObjC-ARC-Based Alias Analysis", false, true)
+INITIALIZE_PASS_DEPENDENCY(TargetLibraryInfoWrapperPass)
+INITIALIZE_PASS_END(ObjCARCAAWrapperPass, "objc-arc-aa",
+                    "ObjC-ARC-Based Alias Analysis", false, true)
+
+ImmutablePass *llvm::createObjCARCAAWrapperPass() {
+  return new ObjCARCAAWrapperPass();
+}
+
+ObjCARCAAWrapperPass::ObjCARCAAWrapperPass() : ImmutablePass(ID) {
+  initializeObjCARCAAWrapperPassPass(*PassRegistry::getPassRegistry());
+}
+
+bool ObjCARCAAWrapperPass::doInitialization(Module &M) {
+  Result.reset(new ObjCARCAAResult(
+      M.getDataLayout(), getAnalysis<TargetLibraryInfoWrapperPass>().getTLI()));
+  return false;
+}
+
+bool ObjCARCAAWrapperPass::doFinalization(Module &M) {
+  Result.reset();
+  return false;
+}
+
+void ObjCARCAAWrapperPass::getAnalysisUsage(AnalysisUsage &AU) const {
+  AU.setPreservesAll();
+  AU.addRequired<TargetLibraryInfoWrapperPass>();
+}