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diff --git a/lib/Transforms/Utils/LowerAllocations.cpp b/lib/Transforms/Utils/LowerAllocations.cpp
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+//===- LowerAllocations.cpp - Reduce malloc & free insts to calls ---------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file 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.
+//
+//===----------------------------------------------------------------------===//
+
+#define DEBUG_TYPE "lowerallocs"
+#include "llvm/Transforms/Scalar.h"
+#include "llvm/Transforms/Utils/UnifyFunctionExitNodes.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"
+#include "llvm/Support/Compiler.h"
+using namespace llvm;
+
+STATISTIC(NumLowered, "Number of allocations lowered");
+
+namespace {
+  /// LowerAllocations - Turn malloc and free instructions into %malloc and
+  /// %free calls.
+  ///
+  class VISIBILITY_HIDDEN LowerAllocations : public BasicBlockPass {
+    Constant *MallocFunc;   // Functions in the module we are processing
+    Constant *FreeFunc;     // Initialized by doInitialization
+    bool LowerMallocArgToInteger;
+  public:
+    static char ID; // Pass ID, replacement for typeid
+    explicit LowerAllocations(bool LowerToInt = false)
+      : BasicBlockPass(&ID), MallocFunc(0), FreeFunc(0), 
+        LowerMallocArgToInteger(LowerToInt) {}
+
+    virtual void getAnalysisUsage(AnalysisUsage &AU) const {
+      AU.addRequired<TargetData>();
+      AU.setPreservesCFG();
+
+      // This is a cluster of orthogonal Transforms:
+      AU.addPreserved<UnifyFunctionExitNodes>();
+      AU.addPreservedID(PromoteMemoryToRegisterID);
+      AU.addPreservedID(LowerSwitchID);
+      AU.addPreservedID(LowerInvokePassID);
+    }
+
+    /// 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 doInitialization(*F.getParent());
+    }
+
+    /// runOnBasicBlock - This method does the actual work of converting
+    /// instructions over, assuming that the pass has already been initialized.
+    ///
+    bool runOnBasicBlock(BasicBlock &BB);
+  };
+}
+
+char LowerAllocations::ID = 0;
+static RegisterPass<LowerAllocations>
+X("lowerallocs", "Lower allocations from instructions to calls");
+
+// Publically exposed interface to pass...
+const PassInfo *const llvm::LowerAllocationsID = &X;
+// createLowerAllocationsPass - Interface to this file...
+Pass *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 *BPTy = PointerType::getUnqual(Type::Int8Ty);
+  // Prototype malloc as "char* malloc(...)", because we don't know in
+  // doInitialization whether size_t is int or long.
+  FunctionType *FT = FunctionType::get(BPTy, std::vector<const Type*>(), true);
+  MallocFunc = M.getOrInsertFunction("malloc", FT);
+  FreeFunc = M.getOrInsertFunction("free"  , Type::VoidTy, BPTy, (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 = ConstantInt::get(Type::Int64Ty,
+                                     TD.getTypeAllocSize(AllocTy));
+      else
+        MallocArg = ConstantExpr::getSizeOf(AllocTy);
+      MallocArg = ConstantExpr::getTruncOrBitCast(cast<Constant>(MallocArg), 
+                                                  IntPtrTy);
+
+      if (MI->isArrayAllocation()) {
+        if (isa<ConstantInt>(MallocArg) &&
+            cast<ConstantInt>(MallocArg)->isOne()) {
+          MallocArg = MI->getOperand(0);         // Operand * 1 = Operand
+        } else if (Constant *CO = dyn_cast<Constant>(MI->getOperand(0))) {
+          CO = ConstantExpr::getIntegerCast(CO, IntPtrTy, false /*ZExt*/);
+          MallocArg = ConstantExpr::getMul(CO, cast<Constant>(MallocArg));
+        } else {
+          Value *Scale = MI->getOperand(0);
+          if (Scale->getType() != IntPtrTy)
+            Scale = CastInst::CreateIntegerCast(Scale, IntPtrTy, false /*ZExt*/,
+                                                "", I);
+
+          // Multiply it by the array size if necessary...
+          MallocArg = BinaryOperator::Create(Instruction::Mul, Scale,
+                                             MallocArg, "", I);
+        }
+      }
+
+      // Create the call to Malloc.
+      CallInst *MCall = CallInst::Create(MallocFunc, MallocArg, "", I);
+      MCall->setTailCall();
+
+      // Create a cast instruction to convert to the right type...
+      Value *MCast;
+      if (MCall->getType() != Type::VoidTy)
+        MCast = new BitCastInst(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)) {
+      Value *PtrCast = 
+        new BitCastInst(FI->getOperand(0),
+                        PointerType::getUnqual(Type::Int8Ty), "", I);
+
+      // Insert a call to the free function...
+      CallInst::Create(FreeFunc, PtrCast, "", I)->setTailCall();
+
+      // Delete the old free instruction
+      I = --BBIL.erase(I);
+      Changed = true;
+      ++NumLowered;
+    }
+  }
+
+  return Changed;
+}
+