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diff --git a/lib/Transforms/Utils/LowerAllocations.cpp b/lib/Transforms/Utils/LowerAllocations.cpp
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+++ b/lib/Transforms/Utils/LowerAllocations.cpp
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+//===- LowerAllocations.cpp - Reduce malloc & free insts to calls ---------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file was developed by the LLVM research group and is distributed under
+// the University of Illinois Open Source License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// The LowerAllocations transformation is a target-dependent tranformation
+// because it depends on the size of data types and alignment constraints.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Transforms/Scalar.h"
+#include "llvm/Module.h"
+#include "llvm/DerivedTypes.h"
+#include "llvm/Instructions.h"
+#include "llvm/Constants.h"
+#include "llvm/Pass.h"
+#include "llvm/ADT/Statistic.h"
+#include "llvm/Target/TargetData.h"
+using namespace llvm;
+
+namespace {
+  Statistic<> NumLowered("lowerallocs", "Number of allocations lowered");
+
+  /// LowerAllocations - Turn malloc and free instructions into %malloc and
+  /// %free calls.
+  ///
+  class LowerAllocations : public BasicBlockPass {
+    Function *MallocFunc;   // Functions in the module we are processing
+    Function *FreeFunc;     // Initialized by doInitialization
+    bool LowerMallocArgToInteger;
+  public:
+    LowerAllocations(bool LowerToInt = false)
+      : MallocFunc(0), FreeFunc(0), LowerMallocArgToInteger(LowerToInt) {}
+
+    virtual void getAnalysisUsage(AnalysisUsage &AU) const {
+      AU.addRequired<TargetData>();
+      AU.setPreservesCFG();
+    }
+
+    /// doPassInitialization - For the lower allocations pass, this ensures that
+    /// a module contains a declaration for a malloc and a free function.
+    ///
+    bool doInitialization(Module &M);
+
+    virtual bool doInitialization(Function &F) {
+      return BasicBlockPass::doInitialization(F);
+    }
+
+    /// runOnBasicBlock - This method does the actual work of converting
+    /// instructions over, assuming that the pass has already been initialized.
+    ///
+    bool runOnBasicBlock(BasicBlock &BB);
+  };
+
+  RegisterOpt<LowerAllocations>
+  X("lowerallocs", "Lower allocations from instructions to calls");
+}
+
+// createLowerAllocationsPass - Interface to this file...
+FunctionPass *llvm::createLowerAllocationsPass(bool LowerMallocArgToInteger) {
+  return new LowerAllocations(LowerMallocArgToInteger);
+}
+
+
+// doInitialization - For the lower allocations pass, this ensures that a
+// module contains a declaration for a malloc and a free function.
+//
+// This function is always successful.
+//
+bool LowerAllocations::doInitialization(Module &M) {
+  const Type *SBPTy = PointerType::get(Type::SByteTy);
+  MallocFunc = M.getNamedFunction("malloc");
+  FreeFunc   = M.getNamedFunction("free");
+
+  if (MallocFunc == 0) {
+    // Prototype malloc as "void* malloc(...)", because we don't know in
+    // doInitialization whether size_t is int or long.
+    FunctionType *FT = FunctionType::get(SBPTy,std::vector<const Type*>(),true);
+    MallocFunc = M.getOrInsertFunction("malloc", FT);
+  }
+  if (FreeFunc == 0)
+    FreeFunc = M.getOrInsertFunction("free"  , Type::VoidTy, SBPTy, (Type *)0);
+
+  return true;
+}
+
+// runOnBasicBlock - This method does the actual work of converting
+// instructions over, assuming that the pass has already been initialized.
+//
+bool LowerAllocations::runOnBasicBlock(BasicBlock &BB) {
+  bool Changed = false;
+  assert(MallocFunc && FreeFunc && "Pass not initialized!");
+
+  BasicBlock::InstListType &BBIL = BB.getInstList();
+
+  const TargetData &TD = getAnalysis<TargetData>();
+  const Type *IntPtrTy = TD.getIntPtrType();
+
+  // Loop over all of the instructions, looking for malloc or free instructions
+  for (BasicBlock::iterator I = BB.begin(), E = BB.end(); I != E; ++I) {
+    if (MallocInst *MI = dyn_cast<MallocInst>(I)) {
+      const Type *AllocTy = MI->getType()->getElementType();
+
+      // malloc(type) becomes sbyte *malloc(size)
+      Value *MallocArg;
+      if (LowerMallocArgToInteger)
+        MallocArg = ConstantUInt::get(Type::ULongTy, TD.getTypeSize(AllocTy));
+      else
+        MallocArg = ConstantExpr::getSizeOf(AllocTy);
+      MallocArg = ConstantExpr::getCast(cast<Constant>(MallocArg), IntPtrTy);
+
+      if (MI->isArrayAllocation()) {
+        if (isa<ConstantInt>(MallocArg) &&
+            cast<ConstantInt>(MallocArg)->getRawValue() == 1) {
+          MallocArg = MI->getOperand(0);         // Operand * 1 = Operand
+        } else if (Constant *CO = dyn_cast<Constant>(MI->getOperand(0))) {
+          CO = ConstantExpr::getCast(CO, IntPtrTy);
+          MallocArg = ConstantExpr::getMul(CO, cast<Constant>(MallocArg));
+        } else {
+          Value *Scale = MI->getOperand(0);
+          if (Scale->getType() != IntPtrTy)
+            Scale = new CastInst(Scale, IntPtrTy, "", I);
+
+          // Multiply it by the array size if necessary...
+          MallocArg = BinaryOperator::create(Instruction::Mul, Scale,
+                                             MallocArg, "", I);
+        }
+      }
+
+      const FunctionType *MallocFTy = MallocFunc->getFunctionType();
+      std::vector<Value*> MallocArgs;
+
+      if (MallocFTy->getNumParams() > 0 || MallocFTy->isVarArg()) {
+        if (MallocFTy->isVarArg()) {
+          if (MallocArg->getType() != IntPtrTy)
+            MallocArg = new CastInst(MallocArg, IntPtrTy, "", I);
+        } else if (MallocFTy->getNumParams() > 0 &&
+                   MallocFTy->getParamType(0) != Type::UIntTy)
+          MallocArg = new CastInst(MallocArg, MallocFTy->getParamType(0), "",I);
+        MallocArgs.push_back(MallocArg);
+      }
+
+      // If malloc is prototyped to take extra arguments, pass nulls.
+      for (unsigned i = 1; i < MallocFTy->getNumParams(); ++i)
+       MallocArgs.push_back(Constant::getNullValue(MallocFTy->getParamType(i)));
+
+      // Create the call to Malloc...
+      CallInst *MCall = new CallInst(MallocFunc, MallocArgs, "", I);
+      MCall->setTailCall();
+
+      // Create a cast instruction to convert to the right type...
+      Value *MCast;
+      if (MCall->getType() != Type::VoidTy)
+        MCast = new CastInst(MCall, MI->getType(), "", I);
+      else
+        MCast = Constant::getNullValue(MI->getType());
+
+      // Replace all uses of the old malloc inst with the cast inst
+      MI->replaceAllUsesWith(MCast);
+      I = --BBIL.erase(I);         // remove and delete the malloc instr...
+      Changed = true;
+      ++NumLowered;
+    } else if (FreeInst *FI = dyn_cast<FreeInst>(I)) {
+      const FunctionType *FreeFTy = FreeFunc->getFunctionType();
+      std::vector<Value*> FreeArgs;
+
+      if (FreeFTy->getNumParams() > 0 || FreeFTy->isVarArg()) {
+        Value *MCast = FI->getOperand(0);
+        if (FreeFTy->getNumParams() > 0 &&
+            FreeFTy->getParamType(0) != MCast->getType())
+          MCast = new CastInst(MCast, FreeFTy->getParamType(0), "", I);
+        FreeArgs.push_back(MCast);
+      }
+
+      // If malloc is prototyped to take extra arguments, pass nulls.
+      for (unsigned i = 1; i < FreeFTy->getNumParams(); ++i)
+       FreeArgs.push_back(Constant::getNullValue(FreeFTy->getParamType(i)));
+
+      // Insert a call to the free function...
+      (new CallInst(FreeFunc, FreeArgs, "", I))->setTailCall();
+
+      // Delete the old free instruction
+      I = --BBIL.erase(I);
+      Changed = true;
+      ++NumLowered;
+    }
+  }
+
+  return Changed;
+}
+