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diff --git a/lib/Target/NVPTX/NVVMReflect.cpp b/lib/Target/NVPTX/NVVMReflect.cpp
new file mode 100644
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+++ b/lib/Target/NVPTX/NVVMReflect.cpp
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+//===- NVVMReflect.cpp - NVVM Emulate conditional compilation -------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This pass replaces occurences of __nvvm_reflect("string") with an
+// integer based on -nvvm-reflect-list string=<int> option given to this pass.
+// If an undefined string value is seen in a call to __nvvm_reflect("string"),
+// a default value of 0 will be used.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/ADT/DenseMap.h"
+#include "llvm/ADT/SmallVector.h"
+#include "llvm/ADT/StringMap.h"
+#include "llvm/Pass.h"
+#include "llvm/IR/Function.h"
+#include "llvm/IR/Module.h"
+#include "llvm/IR/Type.h"
+#include "llvm/IR/DerivedTypes.h"
+#include "llvm/IR/Instructions.h"
+#include "llvm/IR/Constants.h"
+#include "llvm/Support/CommandLine.h"
+#include "llvm/Support/Debug.h"
+#include "llvm/Support/raw_os_ostream.h"
+#include "llvm/Transforms/Scalar.h"
+#include <map>
+#include <sstream>
+#include <string>
+#include <vector>
+
+#define NVVM_REFLECT_FUNCTION "__nvvm_reflect"
+
+using namespace llvm;
+
+namespace llvm { void initializeNVVMReflectPass(PassRegistry &); }
+
+namespace {
+class LLVM_LIBRARY_VISIBILITY NVVMReflect : public ModulePass {
+private:
+  StringMap<int> VarMap;
+  typedef DenseMap<std::string, int>::iterator VarMapIter;
+  Function *ReflectFunction;
+
+public:
+  static char ID;
+  NVVMReflect() : ModulePass(ID) {
+    VarMap.clear();
+    ReflectFunction = 0;
+  }
+
+  void getAnalysisUsage(AnalysisUsage &AU) const { AU.setPreservesAll(); }
+  virtual bool runOnModule(Module &);
+
+  void setVarMap();
+};
+}
+
+static cl::opt<bool>
+NVVMReflectEnabled("nvvm-reflect-enable", cl::init(true),
+                   cl::desc("NVVM reflection, enabled by default"));
+
+char NVVMReflect::ID = 0;
+INITIALIZE_PASS(NVVMReflect, "nvvm-reflect",
+                "Replace occurences of __nvvm_reflect() calls with 0/1", false,
+                false)
+
+static cl::list<std::string>
+ReflectList("nvvm-reflect-list", cl::value_desc("name=<int>"),
+            cl::desc("A list of string=num assignments"),
+            cl::ValueRequired);
+
+/// The command line can look as follows :
+/// -nvvm-reflect-list a=1,b=2 -nvvm-reflect-list c=3,d=0 -R e=2
+/// The strings "a=1,b=2", "c=3,d=0", "e=2" are available in the
+/// ReflectList vector. First, each of ReflectList[i] is 'split'
+/// using "," as the delimiter. Then each of this part is split
+/// using "=" as the delimiter.
+void NVVMReflect::setVarMap() {
+  for (unsigned i = 0, e = ReflectList.size(); i != e; ++i) {
+    DEBUG(dbgs() << "Option : "  << ReflectList[i] << "\n");
+    SmallVector<StringRef, 4> NameValList;
+    StringRef(ReflectList[i]).split(NameValList, ",");
+    for (unsigned j = 0, ej = NameValList.size(); j != ej; ++j) {
+      SmallVector<StringRef, 2> NameValPair;
+      NameValList[j].split(NameValPair, "=");
+      assert(NameValPair.size() == 2 && "name=val expected");
+      std::stringstream ValStream(NameValPair[1]);
+      int Val;
+      ValStream >> Val;
+      assert((!(ValStream.fail())) && "integer value expected");
+      VarMap[NameValPair[0]] = Val;
+    }
+  }
+}
+
+bool NVVMReflect::runOnModule(Module &M) {
+  if (!NVVMReflectEnabled)
+    return false;
+
+  setVarMap();
+
+  ReflectFunction = M.getFunction(NVVM_REFLECT_FUNCTION);
+
+  // If reflect function is not used, then there will be
+  // no entry in the module.
+  if (ReflectFunction == 0)
+    return false;
+
+  // Validate _reflect function
+  assert(ReflectFunction->isDeclaration() &&
+         "_reflect function should not have a body");
+  assert(ReflectFunction->getReturnType()->isIntegerTy() &&
+         "_reflect's return type should be integer");
+
+  std::vector<Instruction *> ToRemove;
+
+  // Go through the uses of ReflectFunction in this Function.
+  // Each of them should a CallInst with a ConstantArray argument.
+  // First validate that. If the c-string corresponding to the
+  // ConstantArray can be found successfully, see if it can be
+  // found in VarMap. If so, replace the uses of CallInst with the
+  // value found in VarMap. If not, replace the use  with value 0.
+  for (Value::use_iterator I = ReflectFunction->use_begin(),
+                           E = ReflectFunction->use_end();
+       I != E; ++I) {
+    assert(isa<CallInst>(*I) && "Only a call instruction can use _reflect");
+    CallInst *Reflect = cast<CallInst>(*I);
+
+    assert((Reflect->getNumOperands() == 2) &&
+           "Only one operand expect for _reflect function");
+    // In cuda, we will have an extra constant-to-generic conversion of
+    // the string.
+    const Value *conv = Reflect->getArgOperand(0);
+    assert(isa<CallInst>(conv) && "Expected a const-to-gen conversion");
+    const CallInst *ConvCall = cast<CallInst>(conv);
+    const Value *str = ConvCall->getArgOperand(0);
+    assert(isa<ConstantExpr>(str) &&
+           "Format of _reflect function not recognized");
+    const ConstantExpr *GEP = cast<ConstantExpr>(str);
+
+    const Value *Sym = GEP->getOperand(0);
+    assert(isa<Constant>(Sym) && "Format of _reflect function not recognized");
+
+    const Constant *SymStr = cast<Constant>(Sym);
+
+    assert(isa<ConstantDataSequential>(SymStr->getOperand(0)) &&
+           "Format of _reflect function not recognized");
+
+    assert(cast<ConstantDataSequential>(SymStr->getOperand(0))->isCString() &&
+           "Format of _reflect function not recognized");
+
+    std::string ReflectArg =
+        cast<ConstantDataSequential>(SymStr->getOperand(0))->getAsString();
+
+    ReflectArg = ReflectArg.substr(0, ReflectArg.size() - 1);
+    DEBUG(dbgs() << "Arg of _reflect : " << ReflectArg << "\n");
+
+    int ReflectVal = 0; // The default value is 0
+    if (VarMap.find(ReflectArg) != VarMap.end()) {
+      ReflectVal = VarMap[ReflectArg];
+    }
+    Reflect->replaceAllUsesWith(
+        ConstantInt::get(Reflect->getType(), ReflectVal));
+    ToRemove.push_back(Reflect);
+  }
+  if (ToRemove.size() == 0)
+    return false;
+
+  for (unsigned i = 0, e = ToRemove.size(); i != e; ++i)
+    ToRemove[i]->eraseFromParent();
+  return true;
+}