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diff --git a/lib/Transforms/IPO/StripSymbols.cpp b/lib/Transforms/IPO/StripSymbols.cpp
new file mode 100644
index 0000000000000..ab8fe5f125e8e
--- /dev/null
+++ b/lib/Transforms/IPO/StripSymbols.cpp
@@ -0,0 +1,415 @@
+//===- StripSymbols.cpp - Strip symbols and debug info from a module ------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// The StripSymbols transformation implements code stripping. Specifically, it
+// can delete:
+// 
+//   * names for virtual registers
+//   * symbols for internal globals and functions
+//   * debug information
+//
+// Note that this transformation makes code much less readable, so it should
+// only be used in situations where the 'strip' utility would be used, such as
+// reducing code size or making it harder to reverse engineer code.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Transforms/IPO.h"
+#include "llvm/Constants.h"
+#include "llvm/DerivedTypes.h"
+#include "llvm/Instructions.h"
+#include "llvm/Module.h"
+#include "llvm/Pass.h"
+#include "llvm/ValueSymbolTable.h"
+#include "llvm/TypeSymbolTable.h"
+#include "llvm/Transforms/Utils/Local.h"
+#include "llvm/Support/Compiler.h"
+#include "llvm/ADT/SmallPtrSet.h"
+using namespace llvm;
+
+namespace {
+  class VISIBILITY_HIDDEN StripSymbols : public ModulePass {
+    bool OnlyDebugInfo;
+  public:
+    static char ID; // Pass identification, replacement for typeid
+    explicit StripSymbols(bool ODI = false) 
+      : ModulePass(&ID), OnlyDebugInfo(ODI) {}
+
+    virtual bool runOnModule(Module &M);
+
+    virtual void getAnalysisUsage(AnalysisUsage &AU) const {
+      AU.setPreservesAll();
+    }
+  };
+
+  class VISIBILITY_HIDDEN StripNonDebugSymbols : public ModulePass {
+  public:
+    static char ID; // Pass identification, replacement for typeid
+    explicit StripNonDebugSymbols()
+      : ModulePass(&ID) {}
+
+    virtual bool runOnModule(Module &M);
+
+    virtual void getAnalysisUsage(AnalysisUsage &AU) const {
+      AU.setPreservesAll();
+    }
+  };
+
+  class VISIBILITY_HIDDEN StripDebugDeclare : public ModulePass {
+  public:
+    static char ID; // Pass identification, replacement for typeid
+    explicit StripDebugDeclare()
+      : ModulePass(&ID) {}
+
+    virtual bool runOnModule(Module &M);
+
+    virtual void getAnalysisUsage(AnalysisUsage &AU) const {
+      AU.setPreservesAll();
+    }
+  };
+}
+
+char StripSymbols::ID = 0;
+static RegisterPass<StripSymbols>
+X("strip", "Strip all symbols from a module");
+
+ModulePass *llvm::createStripSymbolsPass(bool OnlyDebugInfo) {
+  return new StripSymbols(OnlyDebugInfo);
+}
+
+char StripNonDebugSymbols::ID = 0;
+static RegisterPass<StripNonDebugSymbols>
+Y("strip-nondebug", "Strip all symbols, except dbg symbols, from a module");
+
+ModulePass *llvm::createStripNonDebugSymbolsPass() {
+  return new StripNonDebugSymbols();
+}
+
+char StripDebugDeclare::ID = 0;
+static RegisterPass<StripDebugDeclare>
+Z("strip-debug-declare", "Strip all llvm.dbg.declare intrinsics");
+
+ModulePass *llvm::createStripDebugDeclarePass() {
+  return new StripDebugDeclare();
+}
+
+/// OnlyUsedBy - Return true if V is only used by Usr.
+static bool OnlyUsedBy(Value *V, Value *Usr) {
+  for(Value::use_iterator I = V->use_begin(), E = V->use_end(); I != E; ++I) {
+    User *U = *I;
+    if (U != Usr)
+      return false;
+  }
+  return true;
+}
+
+static void RemoveDeadConstant(Constant *C) {
+  assert(C->use_empty() && "Constant is not dead!");
+  SmallPtrSet<Constant *, 4> Operands;
+  for (unsigned i = 0, e = C->getNumOperands(); i != e; ++i)
+    if (isa<DerivedType>(C->getOperand(i)->getType()) &&
+        OnlyUsedBy(C->getOperand(i), C)) 
+      Operands.insert(C->getOperand(i));
+  if (GlobalVariable *GV = dyn_cast<GlobalVariable>(C)) {
+    if (!GV->hasLocalLinkage()) return;   // Don't delete non static globals.
+    GV->eraseFromParent();
+  }
+  else if (!isa<Function>(C))
+    if (isa<CompositeType>(C->getType()))
+      C->destroyConstant();
+
+  // If the constant referenced anything, see if we can delete it as well.
+  for (SmallPtrSet<Constant *, 4>::iterator OI = Operands.begin(),
+         OE = Operands.end(); OI != OE; ++OI)
+    RemoveDeadConstant(*OI);
+}
+
+// Strip the symbol table of its names.
+//
+static void StripSymtab(ValueSymbolTable &ST, bool PreserveDbgInfo) {
+  for (ValueSymbolTable::iterator VI = ST.begin(), VE = ST.end(); VI != VE; ) {
+    Value *V = VI->getValue();
+    ++VI;
+    if (!isa<GlobalValue>(V) || cast<GlobalValue>(V)->hasLocalLinkage()) {
+      if (!PreserveDbgInfo || strncmp(V->getNameStart(), "llvm.dbg", 8))
+        // Set name to "", removing from symbol table!
+        V->setName("");
+    }
+  }
+}
+
+// Strip the symbol table of its names.
+static void StripTypeSymtab(TypeSymbolTable &ST, bool PreserveDbgInfo) {
+  for (TypeSymbolTable::iterator TI = ST.begin(), E = ST.end(); TI != E; ) {
+    if (PreserveDbgInfo && strncmp(TI->first.c_str(), "llvm.dbg", 8) == 0)
+      ++TI;
+    else
+      ST.remove(TI++);
+  }
+}
+
+/// Find values that are marked as llvm.used.
+void findUsedValues(Module &M,
+                    SmallPtrSet<const GlobalValue*, 8>& llvmUsedValues) {
+  if (GlobalVariable *LLVMUsed = M.getGlobalVariable("llvm.used")) {
+    llvmUsedValues.insert(LLVMUsed);
+    // Collect values that are preserved as per explicit request.
+    // llvm.used is used to list these values.
+    if (ConstantArray *Inits = 
+        dyn_cast<ConstantArray>(LLVMUsed->getInitializer())) {
+      for (unsigned i = 0, e = Inits->getNumOperands(); i != e; ++i) {
+        if (GlobalValue *GV = dyn_cast<GlobalValue>(Inits->getOperand(i)))
+          llvmUsedValues.insert(GV);
+        else if (ConstantExpr *CE =
+                 dyn_cast<ConstantExpr>(Inits->getOperand(i)))
+          if (CE->getOpcode() == Instruction::BitCast)
+            if (GlobalValue *GV = dyn_cast<GlobalValue>(CE->getOperand(0)))
+              llvmUsedValues.insert(GV);
+      }
+    }
+  }
+}
+
+/// StripSymbolNames - Strip symbol names.
+bool StripSymbolNames(Module &M, bool PreserveDbgInfo) {
+
+  SmallPtrSet<const GlobalValue*, 8> llvmUsedValues;
+  findUsedValues(M, llvmUsedValues);
+
+  for (Module::global_iterator I = M.global_begin(), E = M.global_end();
+       I != E; ++I) {
+    if (I->hasLocalLinkage() && llvmUsedValues.count(I) == 0)
+      if (!PreserveDbgInfo || strncmp(I->getNameStart(), "llvm.dbg", 8))
+        I->setName("");     // Internal symbols can't participate in linkage
+  }
+  
+  for (Module::iterator I = M.begin(), E = M.end(); I != E; ++I) {
+    if (I->hasLocalLinkage() && llvmUsedValues.count(I) == 0)
+      if (!PreserveDbgInfo || strncmp(I->getNameStart(), "llvm.dbg", 8))
+        I->setName("");     // Internal symbols can't participate in linkage
+    StripSymtab(I->getValueSymbolTable(), PreserveDbgInfo);
+  }
+  
+  // Remove all names from types.
+  StripTypeSymtab(M.getTypeSymbolTable(), PreserveDbgInfo);
+
+  return true;
+}
+
+// StripDebugInfo - Strip debug info in the module if it exists.  
+// To do this, we remove llvm.dbg.func.start, llvm.dbg.stoppoint, and 
+// llvm.dbg.region.end calls, and any globals they point to if now dead.
+bool StripDebugInfo(Module &M) {
+
+  SmallPtrSet<const GlobalValue*, 8> llvmUsedValues;
+  findUsedValues(M, llvmUsedValues);
+
+  // Delete all dbg variables.
+  for (Module::global_iterator I = M.global_begin(), E = M.global_end(); 
+       I != E; ++I) {
+    GlobalVariable *GV = dyn_cast<GlobalVariable>(I);
+    if (!GV) continue;
+    if (!GV->use_empty() && llvmUsedValues.count(I) == 0) {
+      if (strncmp(GV->getNameStart(), "llvm.dbg", 8) == 0) {
+        GV->replaceAllUsesWith(UndefValue::get(GV->getType()));
+      }
+    }
+  }
+
+  Function *FuncStart = M.getFunction("llvm.dbg.func.start");
+  Function *StopPoint = M.getFunction("llvm.dbg.stoppoint");
+  Function *RegionStart = M.getFunction("llvm.dbg.region.start");
+  Function *RegionEnd = M.getFunction("llvm.dbg.region.end");
+  Function *Declare = M.getFunction("llvm.dbg.declare");
+
+  std::vector<Constant*> DeadConstants;
+
+  // Remove all of the calls to the debugger intrinsics, and remove them from
+  // the module.
+  if (FuncStart) {
+    while (!FuncStart->use_empty()) {
+      CallInst *CI = cast<CallInst>(FuncStart->use_back());
+      Value *Arg = CI->getOperand(1);
+      assert(CI->use_empty() && "llvm.dbg intrinsic should have void result");
+      CI->eraseFromParent();
+      if (Arg->use_empty())
+        if (Constant *C = dyn_cast<Constant>(Arg)) 
+          DeadConstants.push_back(C);
+    }
+    FuncStart->eraseFromParent();
+  }
+  if (StopPoint) {
+    while (!StopPoint->use_empty()) {
+      CallInst *CI = cast<CallInst>(StopPoint->use_back());
+      Value *Arg = CI->getOperand(3);
+      assert(CI->use_empty() && "llvm.dbg intrinsic should have void result");
+      CI->eraseFromParent();
+      if (Arg->use_empty())
+        if (Constant *C = dyn_cast<Constant>(Arg)) 
+          DeadConstants.push_back(C);
+    }
+    StopPoint->eraseFromParent();
+  }
+  if (RegionStart) {
+    while (!RegionStart->use_empty()) {
+      CallInst *CI = cast<CallInst>(RegionStart->use_back());
+      Value *Arg = CI->getOperand(1);
+      assert(CI->use_empty() && "llvm.dbg intrinsic should have void result");
+      CI->eraseFromParent();
+      if (Arg->use_empty())
+        if (Constant *C = dyn_cast<Constant>(Arg)) 
+          DeadConstants.push_back(C);
+    }
+    RegionStart->eraseFromParent();
+  }
+  if (RegionEnd) {
+    while (!RegionEnd->use_empty()) {
+      CallInst *CI = cast<CallInst>(RegionEnd->use_back());
+      Value *Arg = CI->getOperand(1);
+      assert(CI->use_empty() && "llvm.dbg intrinsic should have void result");
+      CI->eraseFromParent();
+      if (Arg->use_empty())
+        if (Constant *C = dyn_cast<Constant>(Arg)) 
+          DeadConstants.push_back(C);
+    }
+    RegionEnd->eraseFromParent();
+  }
+  if (Declare) {
+    while (!Declare->use_empty()) {
+      CallInst *CI = cast<CallInst>(Declare->use_back());
+      Value *Arg1 = CI->getOperand(1);
+      Value *Arg2 = CI->getOperand(2);
+      assert(CI->use_empty() && "llvm.dbg intrinsic should have void result");
+      CI->eraseFromParent();
+      if (Arg1->use_empty()) {
+        if (Constant *C = dyn_cast<Constant>(Arg1)) 
+          DeadConstants.push_back(C);
+        else 
+          RecursivelyDeleteTriviallyDeadInstructions(Arg1);
+      }
+      if (Arg2->use_empty())
+        if (Constant *C = dyn_cast<Constant>(Arg2)) 
+          DeadConstants.push_back(C);
+    }
+    Declare->eraseFromParent();
+  }
+
+  // llvm.dbg.compile_units and llvm.dbg.subprograms are marked as linkonce
+  // but since we are removing all debug information, make them internal now.
+  // FIXME: Use private linkage maybe?
+  if (Constant *C = M.getNamedGlobal("llvm.dbg.compile_units"))
+    if (GlobalVariable *GV = dyn_cast<GlobalVariable>(C))
+      GV->setLinkage(GlobalValue::InternalLinkage);
+
+  if (Constant *C = M.getNamedGlobal("llvm.dbg.subprograms"))
+    if (GlobalVariable *GV = dyn_cast<GlobalVariable>(C))
+      GV->setLinkage(GlobalValue::InternalLinkage);
+ 
+  if (Constant *C = M.getNamedGlobal("llvm.dbg.global_variables"))
+    if (GlobalVariable *GV = dyn_cast<GlobalVariable>(C))
+      GV->setLinkage(GlobalValue::InternalLinkage);
+
+  // Delete all dbg variables.
+  for (Module::global_iterator I = M.global_begin(), E = M.global_end(); 
+       I != E; ++I) {
+    GlobalVariable *GV = dyn_cast<GlobalVariable>(I);
+    if (!GV) continue;
+    if (GV->use_empty() && llvmUsedValues.count(I) == 0
+        && (!GV->hasSection() 
+            || strcmp(GV->getSection().c_str(), "llvm.metadata") == 0))
+      DeadConstants.push_back(GV);
+  }
+
+  if (DeadConstants.empty())
+    return false;
+
+  // Delete any internal globals that were only used by the debugger intrinsics.
+  while (!DeadConstants.empty()) {
+    Constant *C = DeadConstants.back();
+    DeadConstants.pop_back();
+    if (GlobalVariable *GV = dyn_cast<GlobalVariable>(C)) {
+      if (GV->hasLocalLinkage())
+        RemoveDeadConstant(GV);
+    }
+    else
+      RemoveDeadConstant(C);
+  }
+
+  // Remove all llvm.dbg types.
+  TypeSymbolTable &ST = M.getTypeSymbolTable();
+  for (TypeSymbolTable::iterator TI = ST.begin(), TE = ST.end(); TI != TE; ) {
+    if (!strncmp(TI->first.c_str(), "llvm.dbg.", 9))
+      ST.remove(TI++);
+    else 
+      ++TI;
+  }
+  
+  return true;
+}
+
+bool StripSymbols::runOnModule(Module &M) {
+  bool Changed = false;
+  Changed |= StripDebugInfo(M);
+  if (!OnlyDebugInfo)
+    Changed |= StripSymbolNames(M, false);
+  return Changed;
+}
+
+bool StripNonDebugSymbols::runOnModule(Module &M) {
+  return StripSymbolNames(M, true);
+}
+
+bool StripDebugDeclare::runOnModule(Module &M) {
+
+  Function *Declare = M.getFunction("llvm.dbg.declare");
+  std::vector<Constant*> DeadConstants;
+
+  if (Declare) {
+    while (!Declare->use_empty()) {
+      CallInst *CI = cast<CallInst>(Declare->use_back());
+      Value *Arg1 = CI->getOperand(1);
+      Value *Arg2 = CI->getOperand(2);
+      assert(CI->use_empty() && "llvm.dbg intrinsic should have void result");
+      CI->eraseFromParent();
+      if (Arg1->use_empty()) {
+        if (Constant *C = dyn_cast<Constant>(Arg1)) 
+          DeadConstants.push_back(C);
+        else 
+          RecursivelyDeleteTriviallyDeadInstructions(Arg1);
+      }
+      if (Arg2->use_empty())
+        if (Constant *C = dyn_cast<Constant>(Arg2)) 
+          DeadConstants.push_back(C);
+    }
+    Declare->eraseFromParent();
+  }
+
+  // Delete all llvm.dbg.global_variables.
+  for (Module::global_iterator I = M.global_begin(), E = M.global_end(); 
+       I != E; ++I) {
+    GlobalVariable *GV = dyn_cast<GlobalVariable>(I);
+    if (!GV) continue;
+    if (GV->use_empty() && GV->hasName() 
+        && strncmp(GV->getNameStart(), "llvm.dbg.global_variable", 24) == 0)
+      DeadConstants.push_back(GV);
+  }
+
+  while (!DeadConstants.empty()) {
+    Constant *C = DeadConstants.back();
+    DeadConstants.pop_back();
+    if (GlobalVariable *GV = dyn_cast<GlobalVariable>(C)) {
+      if (GV->hasLocalLinkage())
+        RemoveDeadConstant(GV);
+    }
+    else
+      RemoveDeadConstant(C);
+  }
+
+  return true;
+}