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diff --git a/contrib/llvm/lib/Transforms/Scalar/GlobalMerge.cpp b/contrib/llvm/lib/Transforms/Scalar/GlobalMerge.cpp
new file mode 100644
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+++ b/contrib/llvm/lib/Transforms/Scalar/GlobalMerge.cpp
@@ -0,0 +1,311 @@
+//===-- GlobalMerge.cpp - Internal globals merging  -----------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+// This pass merges globals with internal linkage into one. This way all the
+// globals which were merged into a biggest one can be addressed using offsets
+// from the same base pointer (no need for separate base pointer for each of the
+// global). Such a transformation can significantly reduce the register pressure
+// when many globals are involved.
+//
+// For example, consider the code which touches several global variables at
+// once:
+//
+// static int foo[N], bar[N], baz[N];
+//
+// for (i = 0; i < N; ++i) {
+//    foo[i] = bar[i] * baz[i];
+// }
+//
+//  On ARM the addresses of 3 arrays should be kept in the registers, thus
+//  this code has quite large register pressure (loop body):
+//
+//  ldr     r1, [r5], #4
+//  ldr     r2, [r6], #4
+//  mul     r1, r2, r1
+//  str     r1, [r0], #4
+//
+//  Pass converts the code to something like:
+//
+//  static struct {
+//    int foo[N];
+//    int bar[N];
+//    int baz[N];
+//  } merged;
+//
+//  for (i = 0; i < N; ++i) {
+//    merged.foo[i] = merged.bar[i] * merged.baz[i];
+//  }
+//
+//  and in ARM code this becomes:
+//
+//  ldr     r0, [r5, #40]
+//  ldr     r1, [r5, #80]
+//  mul     r0, r1, r0
+//  str     r0, [r5], #4
+//
+//  note that we saved 2 registers here almostly "for free".
+// ===---------------------------------------------------------------------===//
+
+#define DEBUG_TYPE "global-merge"
+#include "llvm/Transforms/Scalar.h"
+#include "llvm/ADT/SmallPtrSet.h"
+#include "llvm/ADT/Statistic.h"
+#include "llvm/IR/Attributes.h"
+#include "llvm/IR/Constants.h"
+#include "llvm/IR/DataLayout.h"
+#include "llvm/IR/DerivedTypes.h"
+#include "llvm/IR/Function.h"
+#include "llvm/IR/GlobalVariable.h"
+#include "llvm/IR/Instructions.h"
+#include "llvm/IR/Intrinsics.h"
+#include "llvm/IR/Module.h"
+#include "llvm/Pass.h"
+#include "llvm/Support/CommandLine.h"
+#include "llvm/Target/TargetLowering.h"
+#include "llvm/Target/TargetLoweringObjectFile.h"
+using namespace llvm;
+
+static cl::opt<bool>
+EnableGlobalMergeOnConst("global-merge-on-const", cl::Hidden,
+                  	cl::desc("Enable global merge pass on constants"),
+                  	cl::init(false));
+
+STATISTIC(NumMerged      , "Number of globals merged");
+namespace {
+  class GlobalMerge : public FunctionPass {
+    /// TLI - Keep a pointer of a TargetLowering to consult for determining
+    /// target type sizes.
+    const TargetLowering *TLI;
+
+    bool doMerge(SmallVectorImpl<GlobalVariable*> &Globals,
+                 Module &M, bool isConst, unsigned AddrSpace) const;
+
+    /// \brief Check if the given variable has been identified as must keep
+    /// \pre setMustKeepGlobalVariables must have been called on the Module that
+    ///      contains GV
+    bool isMustKeepGlobalVariable(const GlobalVariable *GV) const {
+      return MustKeepGlobalVariables.count(GV);
+    }
+
+    /// Collect every variables marked as "used" or used in a landing pad
+    /// instruction for this Module.
+    void setMustKeepGlobalVariables(Module &M);
+
+    /// Collect every variables marked as "used"
+    void collectUsedGlobalVariables(Module &M);
+
+    /// Keep track of the GlobalVariable that must not be merged away
+    SmallPtrSet<const GlobalVariable *, 16> MustKeepGlobalVariables;
+
+  public:
+    static char ID;             // Pass identification, replacement for typeid.
+    explicit GlobalMerge(const TargetLowering *tli = 0)
+      : FunctionPass(ID), TLI(tli) {
+      initializeGlobalMergePass(*PassRegistry::getPassRegistry());
+    }
+
+    virtual bool doInitialization(Module &M);
+    virtual bool runOnFunction(Function &F);
+    virtual bool doFinalization(Module &M);
+
+    const char *getPassName() const {
+      return "Merge internal globals";
+    }
+
+    virtual void getAnalysisUsage(AnalysisUsage &AU) const {
+      AU.setPreservesCFG();
+      FunctionPass::getAnalysisUsage(AU);
+    }
+
+    struct GlobalCmp {
+      const DataLayout *TD;
+
+      GlobalCmp(const DataLayout *td) : TD(td) { }
+
+      bool operator()(const GlobalVariable *GV1, const GlobalVariable *GV2) {
+        Type *Ty1 = cast<PointerType>(GV1->getType())->getElementType();
+        Type *Ty2 = cast<PointerType>(GV2->getType())->getElementType();
+
+        return (TD->getTypeAllocSize(Ty1) < TD->getTypeAllocSize(Ty2));
+      }
+    };
+  };
+} // end anonymous namespace
+
+char GlobalMerge::ID = 0;
+INITIALIZE_PASS(GlobalMerge, "global-merge",
+                "Global Merge", false, false)
+
+
+bool GlobalMerge::doMerge(SmallVectorImpl<GlobalVariable*> &Globals,
+                          Module &M, bool isConst, unsigned AddrSpace) const {
+  const DataLayout *TD = TLI->getDataLayout();
+
+  // FIXME: Infer the maximum possible offset depending on the actual users
+  // (these max offsets are different for the users inside Thumb or ARM
+  // functions)
+  unsigned MaxOffset = TLI->getMaximalGlobalOffset();
+
+  // FIXME: Find better heuristics
+  std::stable_sort(Globals.begin(), Globals.end(), GlobalCmp(TD));
+
+  Type *Int32Ty = Type::getInt32Ty(M.getContext());
+
+  for (size_t i = 0, e = Globals.size(); i != e; ) {
+    size_t j = 0;
+    uint64_t MergedSize = 0;
+    std::vector<Type*> Tys;
+    std::vector<Constant*> Inits;
+    for (j = i; j != e; ++j) {
+      Type *Ty = Globals[j]->getType()->getElementType();
+      MergedSize += TD->getTypeAllocSize(Ty);
+      if (MergedSize > MaxOffset) {
+        break;
+      }
+      Tys.push_back(Ty);
+      Inits.push_back(Globals[j]->getInitializer());
+    }
+
+    StructType *MergedTy = StructType::get(M.getContext(), Tys);
+    Constant *MergedInit = ConstantStruct::get(MergedTy, Inits);
+    GlobalVariable *MergedGV = new GlobalVariable(M, MergedTy, isConst,
+                                                  GlobalValue::InternalLinkage,
+                                                  MergedInit, "_MergedGlobals",
+                                                  0, GlobalVariable::NotThreadLocal,
+                                                  AddrSpace);
+    for (size_t k = i; k < j; ++k) {
+      Constant *Idx[2] = {
+        ConstantInt::get(Int32Ty, 0),
+        ConstantInt::get(Int32Ty, k-i)
+      };
+      Constant *GEP = ConstantExpr::getInBoundsGetElementPtr(MergedGV, Idx);
+      Globals[k]->replaceAllUsesWith(GEP);
+      Globals[k]->eraseFromParent();
+      NumMerged++;
+    }
+    i = j;
+  }
+
+  return true;
+}
+
+void GlobalMerge::collectUsedGlobalVariables(Module &M) {
+  // Extract global variables from llvm.used array
+  const GlobalVariable *GV = M.getGlobalVariable("llvm.used");
+  if (!GV || !GV->hasInitializer()) return;
+
+  // Should be an array of 'i8*'.
+  const ConstantArray *InitList = dyn_cast<ConstantArray>(GV->getInitializer());
+  if (InitList == 0) return;
+ 
+  for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i)
+    if (const GlobalVariable *G =
+        dyn_cast<GlobalVariable>(InitList->getOperand(i)->stripPointerCasts()))
+      MustKeepGlobalVariables.insert(G);
+}
+
+void GlobalMerge::setMustKeepGlobalVariables(Module &M) {
+  collectUsedGlobalVariables(M);
+
+  for (Module::iterator IFn = M.begin(), IEndFn = M.end(); IFn != IEndFn;
+       ++IFn) {
+    for (Function::iterator IBB = IFn->begin(), IEndBB = IFn->end();
+         IBB != IEndBB; ++IBB) {
+      // Follow the inwoke link to find the landing pad instruction
+      const InvokeInst *II = dyn_cast<InvokeInst>(IBB->getTerminator());
+      if (!II) continue;
+
+      const LandingPadInst *LPInst = II->getUnwindDest()->getLandingPadInst();
+      // Look for globals in the clauses of the landing pad instruction
+      for (unsigned Idx = 0, NumClauses = LPInst->getNumClauses();
+           Idx != NumClauses; ++Idx)
+        if (const GlobalVariable *GV =
+            dyn_cast<GlobalVariable>(LPInst->getClause(Idx)
+                                     ->stripPointerCasts()))
+          MustKeepGlobalVariables.insert(GV);
+    }
+  }
+}
+
+bool GlobalMerge::doInitialization(Module &M) {
+  DenseMap<unsigned, SmallVector<GlobalVariable*, 16> > Globals, ConstGlobals,
+                                                        BSSGlobals;
+  const DataLayout *TD = TLI->getDataLayout();
+  unsigned MaxOffset = TLI->getMaximalGlobalOffset();
+  bool Changed = false;
+  setMustKeepGlobalVariables(M);
+
+  // Grab all non-const globals.
+  for (Module::global_iterator I = M.global_begin(),
+         E = M.global_end(); I != E; ++I) {
+    // Merge is safe for "normal" internal globals only
+    if (!I->hasLocalLinkage() || I->isThreadLocal() || I->hasSection())
+      continue;
+
+    PointerType *PT = dyn_cast<PointerType>(I->getType());
+    assert(PT && "Global variable is not a pointer!");
+
+    unsigned AddressSpace = PT->getAddressSpace();
+
+    // Ignore fancy-aligned globals for now.
+    unsigned Alignment = TD->getPreferredAlignment(I);
+    Type *Ty = I->getType()->getElementType();
+    if (Alignment > TD->getABITypeAlignment(Ty))
+      continue;
+
+    // Ignore all 'special' globals.
+    if (I->getName().startswith("llvm.") ||
+        I->getName().startswith(".llvm."))
+      continue;
+
+    // Ignore all "required" globals:
+    if (isMustKeepGlobalVariable(I))
+      continue;
+
+    if (TD->getTypeAllocSize(Ty) < MaxOffset) {
+      if (TargetLoweringObjectFile::getKindForGlobal(I, TLI->getTargetMachine())
+          .isBSSLocal())
+        BSSGlobals[AddressSpace].push_back(I);
+      else if (I->isConstant())
+        ConstGlobals[AddressSpace].push_back(I);
+      else
+        Globals[AddressSpace].push_back(I);
+    }
+  }
+
+  for (DenseMap<unsigned, SmallVector<GlobalVariable*, 16> >::iterator
+       I = Globals.begin(), E = Globals.end(); I != E; ++I)
+    if (I->second.size() > 1)
+      Changed |= doMerge(I->second, M, false, I->first);
+
+  for (DenseMap<unsigned, SmallVector<GlobalVariable*, 16> >::iterator
+       I = BSSGlobals.begin(), E = BSSGlobals.end(); I != E; ++I)
+    if (I->second.size() > 1)
+      Changed |= doMerge(I->second, M, false, I->first);
+
+  if (EnableGlobalMergeOnConst)
+    for (DenseMap<unsigned, SmallVector<GlobalVariable*, 16> >::iterator
+         I = ConstGlobals.begin(), E = ConstGlobals.end(); I != E; ++I)
+      if (I->second.size() > 1)
+        Changed |= doMerge(I->second, M, true, I->first);
+
+  return Changed;
+}
+
+bool GlobalMerge::runOnFunction(Function &F) {
+  return false;
+}
+
+bool GlobalMerge::doFinalization(Module &M) {
+  MustKeepGlobalVariables.clear();
+  return false;
+}
+
+Pass *llvm::createGlobalMergePass(const TargetLowering *tli) {
+  return new GlobalMerge(tli);
+}