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diff --git a/contrib/llvm/lib/Transforms/Scalar/GlobalMerge.cpp b/contrib/llvm/lib/Transforms/Scalar/GlobalMerge.cpp
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+++ b/contrib/llvm/lib/Transforms/Scalar/GlobalMerge.cpp
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+//===-- 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/Attributes.h"
+#include "llvm/Constants.h"
+#include "llvm/DerivedTypes.h"
+#include "llvm/Function.h"
+#include "llvm/GlobalVariable.h"
+#include "llvm/Instructions.h"
+#include "llvm/Intrinsics.h"
+#include "llvm/Module.h"
+#include "llvm/Pass.h"
+#include "llvm/Target/TargetData.h"
+#include "llvm/Target/TargetLowering.h"
+#include "llvm/Target/TargetLoweringObjectFile.h"
+#include "llvm/ADT/Statistic.h"
+using namespace llvm;
+
+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) const;
+
+  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);
+
+    const char *getPassName() const {
+      return "Merge internal globals";
+    }
+
+    virtual void getAnalysisUsage(AnalysisUsage &AU) const {
+      AU.setPreservesCFG();
+      FunctionPass::getAnalysisUsage(AU);
+    }
+
+    struct GlobalCmp {
+      const TargetData *TD;
+
+      GlobalCmp(const TargetData *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) const {
+  const TargetData *TD = TLI->getTargetData();
+
+  // 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");
+    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;
+}
+
+
+bool GlobalMerge::doInitialization(Module &M) {
+  SmallVector<GlobalVariable*, 16> Globals, ConstGlobals, BSSGlobals;
+  const TargetData *TD = TLI->getTargetData();
+  unsigned MaxOffset = TLI->getMaximalGlobalOffset();
+  bool Changed = false;
+
+  // 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;
+
+    // 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;
+
+    if (TD->getTypeAllocSize(Ty) < MaxOffset) {
+      if (TargetLoweringObjectFile::getKindForGlobal(I, TLI->getTargetMachine())
+          .isBSSLocal())
+        BSSGlobals.push_back(I);
+      else if (I->isConstant())
+        ConstGlobals.push_back(I);
+      else
+        Globals.push_back(I);
+    }
+  }
+
+  if (Globals.size() > 1)
+    Changed |= doMerge(Globals, M, false);
+  if (BSSGlobals.size() > 1)
+    Changed |= doMerge(BSSGlobals, M, false);
+
+  // FIXME: This currently breaks the EH processing due to way how the 
+  // typeinfo detection works. We might want to detect the TIs and ignore 
+  // them in the future.
+  // if (ConstGlobals.size() > 1)
+  //  Changed |= doMerge(ConstGlobals, M, true);
+
+  return Changed;
+}
+
+bool GlobalMerge::runOnFunction(Function &F) {
+  return false;
+}
+
+Pass *llvm::createGlobalMergePass(const TargetLowering *tli) {
+  return new GlobalMerge(tli);
+}