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diff --git a/contrib/llvm/lib/Analysis/NoAliasAnalysis.cpp b/contrib/llvm/lib/Analysis/NoAliasAnalysis.cpp
new file mode 100644
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+++ b/contrib/llvm/lib/Analysis/NoAliasAnalysis.cpp
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+//===- NoAliasAnalysis.cpp - Minimal Alias Analysis Impl ------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file defines the default implementation of the Alias Analysis interface
+// that simply returns "I don't know" for all queries.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Analysis/Passes.h"
+#include "llvm/Analysis/AliasAnalysis.h"
+#include "llvm/IR/DataLayout.h"
+#include "llvm/IR/LLVMContext.h"
+#include "llvm/IR/Module.h"
+#include "llvm/Pass.h"
+using namespace llvm;
+
+namespace {
+  /// NoAA - This class implements the -no-aa pass, which always returns "I
+  /// don't know" for alias queries.  NoAA is unlike other alias analysis
+  /// implementations, in that it does not chain to a previous analysis.  As
+  /// such it doesn't follow many of the rules that other alias analyses must.
+  ///
+  struct NoAA : public ImmutablePass, public AliasAnalysis {
+    static char ID; // Class identification, replacement for typeinfo
+    NoAA() : ImmutablePass(ID) {
+      initializeNoAAPass(*PassRegistry::getPassRegistry());
+    }
+
+    void getAnalysisUsage(AnalysisUsage &AU) const override {}
+
+    bool doInitialization(Module &M) override {
+      // Note: NoAA does not call InitializeAliasAnalysis because it's
+      // special and does not support chaining.
+      DL = &M.getDataLayout();
+      return true;
+    }
+
+    AliasResult alias(const Location &LocA, const Location &LocB) override {
+      return MayAlias;
+    }
+
+    ModRefBehavior getModRefBehavior(ImmutableCallSite CS) override {
+      return UnknownModRefBehavior;
+    }
+    ModRefBehavior getModRefBehavior(const Function *F) override {
+      return UnknownModRefBehavior;
+    }
+
+    bool pointsToConstantMemory(const Location &Loc, bool OrLocal) override {
+      return false;
+    }
+    Location getArgLocation(ImmutableCallSite CS, unsigned ArgIdx,
+                            ModRefResult &Mask) override {
+      Mask = ModRef;
+      AAMDNodes AATags;
+      CS->getAAMetadata(AATags);
+      return Location(CS.getArgument(ArgIdx), UnknownSize, AATags);
+    }
+
+    ModRefResult getModRefInfo(ImmutableCallSite CS,
+                               const Location &Loc) override {
+      return ModRef;
+    }
+    ModRefResult getModRefInfo(ImmutableCallSite CS1,
+                               ImmutableCallSite CS2) override {
+      return ModRef;
+    }
+
+    void deleteValue(Value *V) override {}
+    void copyValue(Value *From, Value *To) override {}
+    void addEscapingUse(Use &U) override {}
+
+    /// getAdjustedAnalysisPointer - This method is used when a pass implements
+    /// an analysis interface through multiple inheritance.  If needed, it
+    /// should override this to adjust the this pointer as needed for the
+    /// specified pass info.
+    void *getAdjustedAnalysisPointer(const void *ID) override {
+      if (ID == &AliasAnalysis::ID)
+        return (AliasAnalysis*)this;
+      return this;
+    }
+  };
+}  // End of anonymous namespace
+
+// Register this pass...
+char NoAA::ID = 0;
+INITIALIZE_AG_PASS(NoAA, AliasAnalysis, "no-aa",
+                   "No Alias Analysis (always returns 'may' alias)",
+                   true, true, true)
+
+ImmutablePass *llvm::createNoAAPass() { return new NoAA(); }