X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=lib%2FTransforms%2FExprTypeConvert.cpp;h=0f80c2f8bb223fd34a769ca8a2376c7d194abc0c;hb=2a010afefc507cfcd6734435e6a404639a7f81d9;hp=3b0f3d2707443d2eb08195ea61f88b4d6c7ae79e;hpb=c0b90e7dd575ba59035334397722d677231a8f13;p=oota-llvm.git

diff --git a/lib/Transforms/ExprTypeConvert.cpp b/lib/Transforms/ExprTypeConvert.cpp
index 3b0f3d27074..0f80c2f8bb2 100644
--- a/lib/Transforms/ExprTypeConvert.cpp
+++ b/lib/Transforms/ExprTypeConvert.cpp
@@ -1,134 +1,224 @@
-//===- ExprTypeConvert.cpp - Code to change an LLVM Expr Type ---------------=//
+//===- ExprTypeConvert.cpp - Code to change an LLVM Expr Type -------------===//
+// 
+//                     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.
+// 
+//===----------------------------------------------------------------------===//
 //
 // This file implements the part of level raising that checks to see if it is
 // possible to coerce an entire expression tree into a different type.  If
-// convertable, other routines from this file will do the conversion.
+// convertible, other routines from this file will do the conversion.
 //
 //===----------------------------------------------------------------------===//
 
 #include "TransformInternals.h"
-#include "llvm/Method.h"
-#include "llvm/Support/STLExtras.h"
-#include "llvm/iOther.h"
-#include "llvm/iMemory.h"
-#include "llvm/ConstPoolVals.h"
-#include "llvm/Optimizations/ConstantHandling.h"
-#include "llvm/Optimizations/DCE.h"
-#include <map>
+#include "llvm/Constants.h"
+#include "llvm/Instructions.h"
+#include "llvm/Analysis/Expressions.h"
+#include "Support/STLExtras.h"
+#include "Support/Debug.h"
 #include <algorithm>
+using namespace llvm;
 
-#include "llvm/Assembly/Writer.h"
+static bool OperandConvertibleToType(User *U, Value *V, const Type *Ty,
+                                     ValueTypeCache &ConvertedTypes,
+                                     const TargetData &TD);
 
-//#define DEBUG_EXPR_CONVERT 1
+static void ConvertOperandToType(User *U, Value *OldVal, Value *NewVal,
+                                 ValueMapCache &VMC, const TargetData &TD);
+
+// Peephole Malloc instructions: we take a look at the use chain of the
+// malloc instruction, and try to find out if the following conditions hold:
+//   1. The malloc is of the form: 'malloc [sbyte], uint <constant>'
+//   2. The only users of the malloc are cast & add instructions
+//   3. Of the cast instructions, there is only one destination pointer type
+//      [RTy] where the size of the pointed to object is equal to the number
+//      of bytes allocated.
+//
+// If these conditions hold, we convert the malloc to allocate an [RTy]
+// element.  TODO: This comment is out of date WRT arrays
+//
+static bool MallocConvertibleToType(MallocInst *MI, const Type *Ty,
+                                    ValueTypeCache &CTMap,
+                                    const TargetData &TD) {
+  if (!isa<PointerType>(Ty)) return false;   // Malloc always returns pointers
+
+  // Deal with the type to allocate, not the pointer type...
+  Ty = cast<PointerType>(Ty)->getElementType();
+  if (!Ty->isSized()) return false;      // Can only alloc something with a size
+
+  // Analyze the number of bytes allocated...
+  ExprType Expr = ClassifyExpr(MI->getArraySize());
+
+  // Get information about the base datatype being allocated, before & after
+  int ReqTypeSize = TD.getTypeSize(Ty);
+  if (ReqTypeSize == 0) return false;
+  unsigned OldTypeSize = TD.getTypeSize(MI->getType()->getElementType());
+
+  // Must have a scale or offset to analyze it...
+  if (!Expr.Offset && !Expr.Scale && OldTypeSize == 1) return false;
+
+  // Get the offset and scale of the allocation...
+  int64_t OffsetVal = Expr.Offset ? getConstantValue(Expr.Offset) : 0;
+  int64_t ScaleVal = Expr.Scale ? getConstantValue(Expr.Scale) :(Expr.Var != 0);
+
+  // The old type might not be of unit size, take old size into consideration
+  // here...
+  int64_t Offset = OffsetVal * OldTypeSize;
+  int64_t Scale  = ScaleVal  * OldTypeSize;
+  
+  // In order to be successful, both the scale and the offset must be a multiple
+  // of the requested data type's size.
+  //
+  if (Offset/ReqTypeSize*ReqTypeSize != Offset ||
+      Scale/ReqTypeSize*ReqTypeSize != Scale)
+    return false;   // Nope.
 
-static inline const Type *getTy(const Value *V, ValueTypeCache &CT) {
-  ValueTypeCache::iterator I = CT.find(V);
-  if (I == CT.end()) return V->getType();
-  return I->second;
+  return true;
 }
 
-GetElementPtrInst *getAddToGEPResult(const Type *Ty, const Value *V) {
-  const StructType *StructTy = getPointedToStruct(Ty);
-  if (StructTy == 0) return 0;    // Must be a pointer to a struct...
-
-  // Must be a constant unsigned offset value... get it now...
-  if (!isa<ConstPoolUInt>(V)) return 0;
-  unsigned Offset = cast<ConstPoolUInt>(V)->getValue();
- 
-  // Check to make sure the offset is somewhat legitiment w.r.t the struct
-  // type...
-  if (Offset >= TD.getTypeSize(StructTy)) return 0;
-  
-  // If we get this far, we have succeeded... TODO: We need to handle array
-  // indexing as well...
-  const StructLayout *SL = TD.getStructLayout(StructTy);
-  vector<ConstPoolVal*> Offsets;
-  unsigned ActualOffset = Offset;
-  const Type *ElTy = getStructOffsetType(StructTy, ActualOffset, Offsets);
-
-  if (ActualOffset != Offset) return 0;  // TODO: Handle Array indexing...
- 
-  // Success!  Return the GEP instruction, with a dummy first argument.
-  ConstPoolVal *Dummy = ConstPoolVal::getNullConstant(Ty);
-  return new GetElementPtrInst(Dummy, Offsets);
-}
+static Instruction *ConvertMallocToType(MallocInst *MI, const Type *Ty,
+                                        const std::string &Name,
+                                        ValueMapCache &VMC,
+                                        const TargetData &TD){
+  BasicBlock *BB = MI->getParent();
+  BasicBlock::iterator It = BB->end();
 
+  // Analyze the number of bytes allocated...
+  ExprType Expr = ClassifyExpr(MI->getArraySize());
 
+  const PointerType *AllocTy = cast<PointerType>(Ty);
+  const Type *ElType = AllocTy->getElementType();
 
-static bool OperandConvertableToType(User *U, Value *V, const Type *Ty,
-                                     ValueTypeCache &ConvertedTypes);
+  unsigned DataSize = TD.getTypeSize(ElType);
+  unsigned OldTypeSize = TD.getTypeSize(MI->getType()->getElementType());
 
-static void ConvertOperandToType(User *U, Value *OldVal, Value *NewVal,
-                                 ValueMapCache &VMC);
+  // Get the offset and scale coefficients that we are allocating...
+  int64_t OffsetVal = (Expr.Offset ? getConstantValue(Expr.Offset) : 0);
+  int64_t ScaleVal = Expr.Scale ? getConstantValue(Expr.Scale) : (Expr.Var !=0);
+
+  // The old type might not be of unit size, take old size into consideration
+  // here...
+  unsigned Offset = (uint64_t)OffsetVal * OldTypeSize / DataSize;
+  unsigned Scale  = (uint64_t)ScaleVal  * OldTypeSize / DataSize;
+
+  // Locate the malloc instruction, because we may be inserting instructions
+  It = MI;
+
+  // If we have a scale, apply it first...
+  if (Expr.Var) {
+    // Expr.Var is not necessarily unsigned right now, insert a cast now.
+    if (Expr.Var->getType() != Type::UIntTy)
+      Expr.Var = new CastInst(Expr.Var, Type::UIntTy,
+                              Expr.Var->getName()+"-uint", It);
+
+    if (Scale != 1)
+      Expr.Var = BinaryOperator::create(Instruction::Mul, Expr.Var,
+                                        ConstantUInt::get(Type::UIntTy, Scale),
+                                        Expr.Var->getName()+"-scl", It);
 
+  } else {
+    // If we are not scaling anything, just make the offset be the "var"...
+    Expr.Var = ConstantUInt::get(Type::UIntTy, Offset);
+    Offset = 0; Scale = 1;
+  }
+
+  // If we have an offset now, add it in...
+  if (Offset != 0) {
+    assert(Expr.Var && "Var must be nonnull by now!");
+    Expr.Var = BinaryOperator::create(Instruction::Add, Expr.Var,
+                                      ConstantUInt::get(Type::UIntTy, Offset),
+                                      Expr.Var->getName()+"-off", It);
+  }
 
-// ExpressionConvertableToType - Return true if it is possible
-bool ExpressionConvertableToType(Value *V, const Type *Ty,
-                                 ValueTypeCache &CTMap) {
+  assert(AllocTy == Ty);
+  return new MallocInst(AllocTy->getElementType(), Expr.Var, Name);
+}
+
+
+// ExpressionConvertibleToType - Return true if it is possible
+bool llvm::ExpressionConvertibleToType(Value *V, const Type *Ty,
+                                 ValueTypeCache &CTMap, const TargetData &TD) {
   // Expression type must be holdable in a register.
-  if (!isFirstClassType(Ty))
+  if (!Ty->isFirstClassType())
     return false;
   
   ValueTypeCache::iterator CTMI = CTMap.find(V);
   if (CTMI != CTMap.end()) return CTMI->second == Ty;
-  CTMap[V] = Ty;
 
-  // Expressions are only convertable if all of the users of the expression can
-  // have this value converted.  This makes use of the map to avoid infinite
-  // recursion.
+  // If it's a constant... all constants can be converted to a different
+  // type.
   //
-  for (Value::use_iterator I = V->use_begin(), E = V->use_end(); I != E; ++I)
-    if (!OperandConvertableToType(*I, V, Ty, CTMap))
-      return false;
+  if (Constant *CPV = dyn_cast<Constant>(V))
+    return true;
+  
+  CTMap[V] = Ty;
+  if (V->getType() == Ty) return true;  // Expression already correct type!
 
   Instruction *I = dyn_cast<Instruction>(V);
-  if (I == 0) {
-    // It's not an instruction, check to see if it's a constant... all constants
-    // can be converted to an equivalent value (except pointers, they can't be
-    // const prop'd in general).  We just ask the constant propogator to see if
-    // it can convert the value...
-    //
-    if (ConstPoolVal *CPV = dyn_cast<ConstPoolVal>(V))
-      if (opt::ConstantFoldCastInstruction(CPV, Ty))
-        return true;  // Don't worry about deallocating, it's a constant.
-
-    return false;              // Otherwise, we can't convert!
-  }
-  if (I->getType() == Ty) return false;  // Expression already correct type!
+  if (I == 0) return false;              // Otherwise, we can't convert!
 
   switch (I->getOpcode()) {
   case Instruction::Cast:
     // We can convert the expr if the cast destination type is losslessly
-    // convertable to the requested type.
-    return losslessCastableTypes(Ty, I->getType());
+    // convertible to the requested type.
+    if (!Ty->isLosslesslyConvertibleTo(I->getType())) return false;
+
+    // We also do not allow conversion of a cast that casts from a ptr to array
+    // of X to a *X.  For example: cast [4 x %List *] * %val to %List * *
+    //
+    if (const PointerType *SPT = 
+        dyn_cast<PointerType>(I->getOperand(0)->getType()))
+      if (const PointerType *DPT = dyn_cast<PointerType>(I->getType()))
+        if (const ArrayType *AT = dyn_cast<ArrayType>(SPT->getElementType()))
+          if (AT->getElementType() == DPT->getElementType())
+            return false;
+    break;
 
   case Instruction::Add:
   case Instruction::Sub:
-    return ExpressionConvertableToType(I->getOperand(0), Ty, CTMap) &&
-           ExpressionConvertableToType(I->getOperand(1), Ty, CTMap);
+    if (!Ty->isInteger() && !Ty->isFloatingPoint()) return false;
+    if (!ExpressionConvertibleToType(I->getOperand(0), Ty, CTMap, TD) ||
+        !ExpressionConvertibleToType(I->getOperand(1), Ty, CTMap, TD))
+      return false;
+    break;
   case Instruction::Shr:
+    if (!Ty->isInteger()) return false;
     if (Ty->isSigned() != V->getType()->isSigned()) return false;
     // FALL THROUGH
   case Instruction::Shl:
-    return ExpressionConvertableToType(I->getOperand(0), Ty, CTMap);
+    if (!Ty->isInteger()) return false;
+    if (!ExpressionConvertibleToType(I->getOperand(0), Ty, CTMap, TD))
+      return false;
+    break;
 
   case Instruction::Load: {
     LoadInst *LI = cast<LoadInst>(I);
-    if (LI->hasIndices()) return false;
-
-    return ExpressionConvertableToType(LI->getPtrOperand(),
-                                       PointerType::get(Ty), CTMap);
+    if (!ExpressionConvertibleToType(LI->getPointerOperand(),
+                                     PointerType::get(Ty), CTMap, TD))
+      return false;
+    break;                                     
   }
-  case Instruction::PHINode: {
+  case Instruction::PHI: {
     PHINode *PN = cast<PHINode>(I);
+    // Be conservative if we find a giant PHI node.
+    if (PN->getNumIncomingValues() > 32) return false;
+
     for (unsigned i = 0; i < PN->getNumIncomingValues(); ++i)
-      if (!ExpressionConvertableToType(PN->getIncomingValue(i), Ty, CTMap))
+      if (!ExpressionConvertibleToType(PN->getIncomingValue(i), Ty, CTMap, TD))
         return false;
-    return true;
+    break;
   }
 
+  case Instruction::Malloc:
+    if (!MallocConvertibleToType(cast<MallocInst>(I), Ty, CTMap, TD))
+      return false;
+    break;
+
   case Instruction::GetElementPtr: {
-    // GetElementPtr's are directly convertable to a pointer type if they have
+    // GetElementPtr's are directly convertible to a pointer type if they have
     // a number of zeros at the end.  Because removing these values does not
     // change the logical offset of the GEP, it is okay and fair to remove them.
     // This can change this:
@@ -139,69 +229,148 @@ bool ExpressionConvertableToType(Value *V, const Type *Ty,
     // 
     GetElementPtrInst *GEP = cast<GetElementPtrInst>(I);
     const PointerType *PTy = dyn_cast<PointerType>(Ty);
-    if (!PTy) return false;
+    if (!PTy) return false;  // GEP must always return a pointer...
+    const Type *PVTy = PTy->getElementType();
 
     // Check to see if there are zero elements that we can remove from the
     // index array.  If there are, check to see if removing them causes us to
     // get to the right type...
     //
-    vector<ConstPoolVal*> Indices = GEP->getIndices();
-    const Type *BaseType = GEP->getPtrOperand()->getType();
+    std::vector<Value*> Indices(GEP->idx_begin(), GEP->idx_end());
+    const Type *BaseType = GEP->getPointerOperand()->getType();
+    const Type *ElTy = 0;
 
-    while (Indices.size() &&
-           cast<ConstPoolUInt>(Indices.back())->getValue() == 0) {
+    while (!Indices.empty() &&
+           Indices.back() == Constant::getNullValue(Indices.back()->getType())){
       Indices.pop_back();
-      const Type *ElTy = GetElementPtrInst::getIndexedType(BaseType, Indices,
-                                                           true);
-      if (ElTy == PTy->getValueType())
-        return true;  // Found a match!!
+      ElTy = GetElementPtrInst::getIndexedType(BaseType, Indices, true);
+      if (ElTy == PVTy)
+        break;  // Found a match!!
+      ElTy = 0;
     }
-    break;   // No match, maybe next time.
+
+    if (ElTy) break;   // Found a number of zeros we can strip off!
+
+    // Otherwise, we can convert a GEP from one form to the other iff the
+    // current gep is of the form 'getelementptr sbyte*, long N
+    // and we could convert this to an appropriate GEP for the new type.
+    //
+    if (GEP->getNumOperands() == 2 &&
+        GEP->getType() == PointerType::get(Type::SByteTy)) {
+
+      // Do not Check to see if our incoming pointer can be converted
+      // to be a ptr to an array of the right type... because in more cases than
+      // not, it is simply not analyzable because of pointer/array
+      // discrepancies.  To fix this, we will insert a cast before the GEP.
+      //
+
+      // Check to see if 'N' is an expression that can be converted to
+      // the appropriate size... if so, allow it.
+      //
+      std::vector<Value*> Indices;
+      const Type *ElTy = ConvertibleToGEP(PTy, I->getOperand(1), Indices, TD);
+      if (ElTy == PVTy) {
+        if (!ExpressionConvertibleToType(I->getOperand(0),
+                                         PointerType::get(ElTy), CTMap, TD))
+          return false;  // Can't continue, ExConToTy might have polluted set!
+        break;
+      }
+    }
+
+    // Otherwise, it could be that we have something like this:
+    //     getelementptr [[sbyte] *] * %reg115, long %reg138    ; [sbyte]**
+    // and want to convert it into something like this:
+    //     getelemenptr [[int] *] * %reg115, long %reg138      ; [int]**
+    //
+    if (GEP->getNumOperands() == 2 && 
+        PTy->getElementType()->isSized() &&
+        TD.getTypeSize(PTy->getElementType()) == 
+        TD.getTypeSize(GEP->getType()->getElementType())) {
+      const PointerType *NewSrcTy = PointerType::get(PVTy);
+      if (!ExpressionConvertibleToType(I->getOperand(0), NewSrcTy, CTMap, TD))
+        return false;
+      break;
+    }
+
+    return false;   // No match, maybe next time.
+  }
+
+  case Instruction::Call: {
+    if (isa<Function>(I->getOperand(0)))
+      return false;  // Don't even try to change direct calls.
+
+    // If this is a function pointer, we can convert the return type if we can
+    // convert the source function pointer.
+    //
+    const PointerType *PT = cast<PointerType>(I->getOperand(0)->getType());
+    const FunctionType *FT = cast<FunctionType>(PT->getElementType());
+    std::vector<const Type *> ArgTys(FT->param_begin(), FT->param_end());
+    const FunctionType *NewTy =
+      FunctionType::get(Ty, ArgTys, FT->isVarArg());
+    if (!ExpressionConvertibleToType(I->getOperand(0),
+                                     PointerType::get(NewTy), CTMap, TD))
+      return false;
+    break;
   }
+  default:
+    return false;
   }
-  return false;
-}
 
+  // Expressions are only convertible if all of the users of the expression can
+  // have this value converted.  This makes use of the map to avoid infinite
+  // recursion.
+  //
+  for (Value::use_iterator It = I->use_begin(), E = I->use_end(); It != E; ++It)
+    if (!OperandConvertibleToType(*It, I, Ty, CTMap, TD))
+      return false;
+
+  return true;
+}
 
 
+Value *llvm::ConvertExpressionToType(Value *V, const Type *Ty, 
+                                     ValueMapCache &VMC, const TargetData &TD) {
+  if (V->getType() == Ty) return V;  // Already where we need to be?
 
-Value *ConvertExpressionToType(Value *V, const Type *Ty, ValueMapCache &VMC) {
   ValueMapCache::ExprMapTy::iterator VMCI = VMC.ExprMap.find(V);
-  if (VMCI != VMC.ExprMap.end())
+  if (VMCI != VMC.ExprMap.end()) {
+    const Value *GV = VMCI->second;
+    const Type *GTy = VMCI->second->getType();
+    assert(VMCI->second->getType() == Ty);
+
+    if (Instruction *I = dyn_cast<Instruction>(V))
+      ValueHandle IHandle(VMC, I);  // Remove I if it is unused now!
+
     return VMCI->second;
+  }
 
-#ifdef DEBUG_EXPR_CONVERT
-  cerr << "CETT: " << (void*)V << " " << V;
-#endif
+  DEBUG(std::cerr << "CETT: " << (void*)V << " " << *V);
 
   Instruction *I = dyn_cast<Instruction>(V);
-  if (I == 0)
-    if (ConstPoolVal *CPV = cast<ConstPoolVal>(V)) {
-      // Constants are converted by constant folding the cast that is required.
-      // We assume here that all casts are implemented for constant prop.
-      Value *Result = opt::ConstantFoldCastInstruction(CPV, Ty);
-      assert(Result && "ConstantFoldCastInstruction Failed!!!");
-
-      // Add the instruction to the expression map
-      VMC.ExprMap[V] = Result;
-      return Result;
-    }
+  if (I == 0) {
+    Constant *CPV = cast<Constant>(V);
+    // Constants are converted by constant folding the cast that is required.
+    // We assume here that all casts are implemented for constant prop.
+    Value *Result = ConstantExpr::getCast(CPV, Ty);
+    // Add the instruction to the expression map
+    //VMC.ExprMap[V] = Result;
+    return Result;
+  }
 
 
   BasicBlock *BB = I->getParent();
-  BasicBlock::InstListType &BIL = BB->getInstList();
-  string Name = I->getName();  if (!Name.empty()) I->setName("");
+  std::string Name = I->getName();  if (!Name.empty()) I->setName("");
   Instruction *Res;     // Result of conversion
 
-  ValueHandle IHandle(I);  // Prevent I from being removed!
+  ValueHandle IHandle(VMC, I);  // Prevent I from being removed!
   
-  ConstPoolVal *Dummy = ConstPoolVal::getNullConstant(Ty);
-
-  //cerr << endl << endl << "Type:\t" << Ty << "\nInst: " << I << "BB Before: " << BB << endl;
+  Constant *Dummy = Constant::getNullValue(Ty);
 
   switch (I->getOpcode()) {
   case Instruction::Cast:
+    assert(VMC.NewCasts.count(ValueHandle(VMC, I)) == 0);
     Res = new CastInst(I->getOperand(0), Ty, Name);
+    VMC.NewCasts.insert(ValueHandle(VMC, Res));
     break;
     
   case Instruction::Add:
@@ -210,8 +379,8 @@ Value *ConvertExpressionToType(Value *V, const Type *Ty, ValueMapCache &VMC) {
                                  Dummy, Dummy, Name);
     VMC.ExprMap[I] = Res;   // Add node to expression eagerly
 
-    Res->setOperand(0, ConvertExpressionToType(I->getOperand(0), Ty, VMC));
-    Res->setOperand(1, ConvertExpressionToType(I->getOperand(1), Ty, VMC));
+    Res->setOperand(0, ConvertExpressionToType(I->getOperand(0), Ty, VMC, TD));
+    Res->setOperand(1, ConvertExpressionToType(I->getOperand(1), Ty, VMC, TD));
     break;
 
   case Instruction::Shl:
@@ -219,21 +388,23 @@ Value *ConvertExpressionToType(Value *V, const Type *Ty, ValueMapCache &VMC) {
     Res = new ShiftInst(cast<ShiftInst>(I)->getOpcode(), Dummy,
                         I->getOperand(1), Name);
     VMC.ExprMap[I] = Res;
-    Res->setOperand(0, ConvertExpressionToType(I->getOperand(0), Ty, VMC));
+    Res->setOperand(0, ConvertExpressionToType(I->getOperand(0), Ty, VMC, TD));
     break;
 
   case Instruction::Load: {
     LoadInst *LI = cast<LoadInst>(I);
-    assert(!LI->hasIndices());
-    Res = new LoadInst(ConstPoolVal::getNullConstant(PointerType::get(Ty)), 
-                       Name);
+
+    Res = new LoadInst(Constant::getNullValue(PointerType::get(Ty)), Name);
     VMC.ExprMap[I] = Res;
-    Res->setOperand(0, ConvertExpressionToType(LI->getPtrOperand(),
-                                               PointerType::get(Ty), VMC));
+    Res->setOperand(0, ConvertExpressionToType(LI->getPointerOperand(),
+                                               PointerType::get(Ty), VMC, TD));
+    assert(Res->getOperand(0)->getType() == PointerType::get(Ty));
+    assert(Ty == Res->getType());
+    assert(Res->getType()->isFirstClassType() && "Load of structure or array!");
     break;
   }
 
-  case Instruction::PHINode: {
+  case Instruction::PHI: {
     PHINode *OldPN = cast<PHINode>(I);
     PHINode *NewPN = new PHINode(Ty, Name);
 
@@ -241,17 +412,22 @@ Value *ConvertExpressionToType(Value *V, const Type *Ty, ValueMapCache &VMC) {
     while (OldPN->getNumOperands()) {
       BasicBlock *BB = OldPN->getIncomingBlock(0);
       Value *OldVal = OldPN->getIncomingValue(0);
-      ValueHandle OldValHandle(OldVal);
-      OldPN->removeIncomingValue(BB);
-      Value *V = ConvertExpressionToType(OldVal, Ty, VMC);
+      ValueHandle OldValHandle(VMC, OldVal);
+      OldPN->removeIncomingValue(BB, false);
+      Value *V = ConvertExpressionToType(OldVal, Ty, VMC, TD);
       NewPN->addIncoming(V, BB);
     }
     Res = NewPN;
     break;
   }
 
+  case Instruction::Malloc: {
+    Res = ConvertMallocToType(cast<MallocInst>(I), Ty, Name, VMC, TD);
+    break;
+  }
+
   case Instruction::GetElementPtr: {
-    // GetElementPtr's are directly convertable to a pointer type if they have
+    // GetElementPtr's are directly convertible to a pointer type if they have
     // a number of zeros at the end.  Because removing these values does not
     // change the logical offset of the GEP, it is okay and fair to remove them.
     // This can change this:
@@ -266,72 +442,125 @@ Value *ConvertExpressionToType(Value *V, const Type *Ty, ValueMapCache &VMC) {
     // index array.  If there are, check to see if removing them causes us to
     // get to the right type...
     //
-    vector<ConstPoolVal*> Indices = GEP->getIndices();
-    const Type *BaseType = GEP->getPtrOperand()->getType();
-    const Type *PVTy = cast<PointerType>(Ty)->getValueType();
+    std::vector<Value*> Indices(GEP->idx_begin(), GEP->idx_end());
+    const Type *BaseType = GEP->getPointerOperand()->getType();
+    const Type *PVTy = cast<PointerType>(Ty)->getElementType();
     Res = 0;
-    while (Indices.size() &&
-           cast<ConstPoolUInt>(Indices.back())->getValue() == 0) {
+    while (!Indices.empty() &&
+           Indices.back() == Constant::getNullValue(Indices.back()->getType())){
       Indices.pop_back();
       if (GetElementPtrInst::getIndexedType(BaseType, Indices, true) == PVTy) {
-        if (Indices.size() == 0) {
-          Res = new CastInst(GEP->getPtrOperand(), BaseType); // NOOP
-        } else {
-          Res = new GetElementPtrInst(GEP->getPtrOperand(), Indices, Name);
-        }
+        if (Indices.size() == 0)
+          Res = new CastInst(GEP->getPointerOperand(), BaseType); // NOOP CAST
+        else
+          Res = new GetElementPtrInst(GEP->getPointerOperand(), Indices, Name);
         break;
       }
     }
+
+    if (Res == 0 && GEP->getNumOperands() == 2 &&
+        GEP->getType() == PointerType::get(Type::SByteTy)) {
+      
+      // Otherwise, we can convert a GEP from one form to the other iff the
+      // current gep is of the form 'getelementptr sbyte*, unsigned N
+      // and we could convert this to an appropriate GEP for the new type.
+      //
+      const PointerType *NewSrcTy = PointerType::get(PVTy);
+      BasicBlock::iterator It = I;
+
+      // Check to see if 'N' is an expression that can be converted to
+      // the appropriate size... if so, allow it.
+      //
+      std::vector<Value*> Indices;
+      const Type *ElTy = ConvertibleToGEP(NewSrcTy, I->getOperand(1),
+                                          Indices, TD, &It);
+      if (ElTy) {        
+        assert(ElTy == PVTy && "Internal error, setup wrong!");
+        Res = new GetElementPtrInst(Constant::getNullValue(NewSrcTy),
+                                    Indices, Name);
+        VMC.ExprMap[I] = Res;
+        Res->setOperand(0, ConvertExpressionToType(I->getOperand(0),
+                                                   NewSrcTy, VMC, TD));
+      }
+    }
+
+    // Otherwise, it could be that we have something like this:
+    //     getelementptr [[sbyte] *] * %reg115, uint %reg138    ; [sbyte]**
+    // and want to convert it into something like this:
+    //     getelemenptr [[int] *] * %reg115, uint %reg138      ; [int]**
+    //
+    if (Res == 0) {
+      const PointerType *NewSrcTy = PointerType::get(PVTy);
+      std::vector<Value*> Indices(GEP->idx_begin(), GEP->idx_end());
+      Res = new GetElementPtrInst(Constant::getNullValue(NewSrcTy),
+                                  Indices, Name);
+      VMC.ExprMap[I] = Res;
+      Res->setOperand(0, ConvertExpressionToType(I->getOperand(0),
+                                                 NewSrcTy, VMC, TD));
+    }
+
+
     assert(Res && "Didn't find match!");
-    break;   // No match, maybe next time.
+    break;
   }
 
+  case Instruction::Call: {
+    assert(!isa<Function>(I->getOperand(0)));
+
+    // If this is a function pointer, we can convert the return type if we can
+    // convert the source function pointer.
+    //
+    const PointerType *PT = cast<PointerType>(I->getOperand(0)->getType());
+    const FunctionType *FT = cast<FunctionType>(PT->getElementType());
+    std::vector<const Type *> ArgTys(FT->param_begin(), FT->param_end());
+    const FunctionType *NewTy =
+      FunctionType::get(Ty, ArgTys, FT->isVarArg());
+    const PointerType *NewPTy = PointerType::get(NewTy);
+    if (Ty == Type::VoidTy)
+      Name = "";  // Make sure not to name calls that now return void!
+
+    Res = new CallInst(Constant::getNullValue(NewPTy),
+                       std::vector<Value*>(I->op_begin()+1, I->op_end()),
+                       Name);
+    VMC.ExprMap[I] = Res;
+    Res->setOperand(0, ConvertExpressionToType(I->getOperand(0),NewPTy,VMC,TD));
+    break;
+  }
   default:
-    assert(0 && "Expression convertable, but don't know how to convert?");
+    assert(0 && "Expression convertible, but don't know how to convert?");
     return 0;
   }
 
-  BasicBlock::iterator It = find(BIL.begin(), BIL.end(), I);
-  assert(It != BIL.end() && "Instruction not in own basic block??");
-  BIL.insert(It, Res);
+  assert(Res->getType() == Ty && "Didn't convert expr to correct type!");
+
+  BB->getInstList().insert(I, Res);
 
   // Add the instruction to the expression map
   VMC.ExprMap[I] = Res;
 
-  // Expressions are only convertable if all of the users of the expression can
-  // have this value converted.  This makes use of the map to avoid infinite
-  // recursion.
-  //
+
   unsigned NumUses = I->use_size();
   for (unsigned It = 0; It < NumUses; ) {
     unsigned OldSize = NumUses;
-    ConvertOperandToType(*(I->use_begin()+It), I, Res, VMC);
+    Value::use_iterator UI = I->use_begin();
+    std::advance(UI, It);
+    ConvertOperandToType(*UI, I, Res, VMC, TD);
     NumUses = I->use_size();
     if (NumUses == OldSize) ++It;
   }
 
-#ifdef DEBUG_EXPR_CONVERT
-  cerr << "ExpIn: " << (void*)I << " " << I
-       << "ExpOut: " << (void*)Res << " " << Res;
-  cerr << "ExpCREATED: " << (void*)Res << " " << Res;
-#endif
-
-  if (I->use_empty()) {
-#ifdef DEBUG_EXPR_CONVERT
-    cerr << "EXPR DELETING: " << (void*)I << " " << I;
-#endif
-    BIL.remove(I);
-    delete I;
-  }
+  DEBUG(std::cerr << "ExpIn: " << (void*)I << " " << *I
+                  << "ExpOut: " << (void*)Res << " " << *Res);
 
   return Res;
 }
 
 
 
-// RetValConvertableToType - Return true if it is possible
-bool RetValConvertableToType(Value *V, const Type *Ty,
-                             ValueTypeCache &ConvertedTypes) {
+// ValueConvertibleToType - Return true if it is possible
+bool llvm::ValueConvertibleToType(Value *V, const Type *Ty,
+                                  ValueTypeCache &ConvertedTypes,
+                                  const TargetData &TD) {
   ValueTypeCache::iterator I = ConvertedTypes.find(V);
   if (I != ConvertedTypes.end()) return I->second == Ty;
   ConvertedTypes[V] = Ty;
@@ -339,9 +568,11 @@ bool RetValConvertableToType(Value *V, const Type *Ty,
   // It is safe to convert the specified value to the specified type IFF all of
   // the uses of the value can be converted to accept the new typed value.
   //
-  for (Value::use_iterator I = V->use_begin(), E = V->use_end(); I != E; ++I)
-    if (!OperandConvertableToType(*I, V, Ty, ConvertedTypes))
-      return false;
+  if (V->getType() != Ty) {
+    for (Value::use_iterator I = V->use_begin(), E = V->use_end(); I != E; ++I)
+      if (!OperandConvertibleToType(*I, V, Ty, ConvertedTypes, TD))
+        return false;
+  }
 
   return true;
 }
@@ -350,20 +581,19 @@ bool RetValConvertableToType(Value *V, const Type *Ty,
 
 
 
-
-
-// OperandConvertableToType - Return true if it is possible to convert operand
+// OperandConvertibleToType - Return true if it is possible to convert operand
 // V of User (instruction) U to the specified type.  This is true iff it is
 // possible to change the specified instruction to accept this.  CTMap is a map
 // of converted types, so that circular definitions will see the future type of
 // the expression, not the static current type.
 //
-static bool OperandConvertableToType(User *U, Value *V, const Type *Ty,
-                                     ValueTypeCache &CTMap) {
-  if (V->getType() == Ty) return true;   // Already the right type?
+static bool OperandConvertibleToType(User *U, Value *V, const Type *Ty,
+                                     ValueTypeCache &CTMap,
+                                     const TargetData &TD) {
+  //  if (V->getType() == Ty) return true;   // Operand already the right type?
 
   // Expression type must be holdable in a register.
-  if (!isFirstClassType(Ty))
+  if (!Ty->isFirstClassType())
     return false;
 
   Instruction *I = dyn_cast<Instruction>(U);
@@ -373,150 +603,307 @@ static bool OperandConvertableToType(User *U, Value *V, const Type *Ty,
   case Instruction::Cast:
     assert(I->getOperand(0) == V);
     // We can convert the expr if the cast destination type is losslessly
-    // convertable to the requested type.
-    return losslessCastableTypes(Ty, I->getOperand(0)->getType());
+    // convertible to the requested type.
+    // Also, do not change a cast that is a noop cast.  For all intents and
+    // purposes it should be eliminated.
+    if (!Ty->isLosslesslyConvertibleTo(I->getOperand(0)->getType()) ||
+        I->getType() == I->getOperand(0)->getType())
+      return false;
+
+    // Do not allow a 'cast ushort %V to uint' to have it's first operand be
+    // converted to a 'short' type.  Doing so changes the way sign promotion
+    // happens, and breaks things.  Only allow the cast to take place if the
+    // signedness doesn't change... or if the current cast is not a lossy
+    // conversion.
+    //
+    if (!I->getType()->isLosslesslyConvertibleTo(I->getOperand(0)->getType()) &&
+        I->getOperand(0)->getType()->isSigned() != Ty->isSigned())
+      return false;
+
+    // We also do not allow conversion of a cast that casts from a ptr to array
+    // of X to a *X.  For example: cast [4 x %List *] * %val to %List * *
+    //
+    if (const PointerType *SPT = 
+        dyn_cast<PointerType>(I->getOperand(0)->getType()))
+      if (const PointerType *DPT = dyn_cast<PointerType>(I->getType()))
+        if (const ArrayType *AT = dyn_cast<ArrayType>(SPT->getElementType()))
+          if (AT->getElementType() == DPT->getElementType())
+            return false;
+    return true;
 
   case Instruction::Add:
-    if (V == I->getOperand(0) && isa<CastInst>(I->getOperand(1))) {
-      Instruction *GEP =
-        getAddToGEPResult(Ty, cast<CastInst>(I->getOperand(1))->getOperand(0));
-      if (GEP) {  // If successful, this Add can be converted to a GEP.
-        const Type *RetTy = GEP->getType();  // Get the new type...
-        delete GEP;  // We don't want the actual instruction yet...
+    if (isa<PointerType>(Ty)) {
+      Value *IndexVal = I->getOperand(V == I->getOperand(0) ? 1 : 0);
+      std::vector<Value*> Indices;
+      if (const Type *ETy = ConvertibleToGEP(Ty, IndexVal, Indices, TD)) {
+        const Type *RetTy = PointerType::get(ETy);
+
         // Only successful if we can convert this type to the required type
-        return RetValConvertableToType(I, RetTy, CTMap);
+        if (ValueConvertibleToType(I, RetTy, CTMap, TD)) {
+          CTMap[I] = RetTy;
+          return true;
+        }
+        // We have to return failure here because ValueConvertibleToType could 
+        // have polluted our map
+        return false;
       }
     }
     // FALLTHROUGH
   case Instruction::Sub: {
+    if (!Ty->isInteger() && !Ty->isFloatingPoint()) return false;
+
     Value *OtherOp = I->getOperand((V == I->getOperand(0)) ? 1 : 0);
-    return RetValConvertableToType(I, Ty, CTMap) &&
-           ExpressionConvertableToType(OtherOp, Ty, CTMap);
+    return ValueConvertibleToType(I, Ty, CTMap, TD) &&
+           ExpressionConvertibleToType(OtherOp, Ty, CTMap, TD);
   }
   case Instruction::SetEQ:
   case Instruction::SetNE: {
     Value *OtherOp = I->getOperand((V == I->getOperand(0)) ? 1 : 0);
-    return ExpressionConvertableToType(OtherOp, Ty, CTMap);
+    return ExpressionConvertibleToType(OtherOp, Ty, CTMap, TD);
   }
   case Instruction::Shr:
     if (Ty->isSigned() != V->getType()->isSigned()) return false;
     // FALL THROUGH
   case Instruction::Shl:
+    if (I->getOperand(1) == V) return false;  // Cannot change shift amount type
+    if (!Ty->isInteger()) return false;
+    return ValueConvertibleToType(I, Ty, CTMap, TD);
+
+  case Instruction::Free:
     assert(I->getOperand(0) == V);
-    return RetValConvertableToType(I, Ty, CTMap);
+    return isa<PointerType>(Ty);    // Free can free any pointer type!
 
   case Instruction::Load:
-    assert(I->getOperand(0) == V);
+    // Cannot convert the types of any subscripts...
+    if (I->getOperand(0) != V) return false;
+
     if (const PointerType *PT = dyn_cast<PointerType>(Ty)) {
       LoadInst *LI = cast<LoadInst>(I);
-      const Type *PVTy = PT->getValueType();
-
-      if (LI->hasIndices() || isa<ArrayType>(PVTy))
-        return false;
-
-      if (!isFirstClassType(PVTy)) {
-        // They could be loading the first element of a structure type...
-        if (const StructType *ST = dyn_cast<StructType>(PVTy)) {
-          unsigned Offset = 0;   // No offset, get first leaf.
-          vector<ConstPoolVal*> Offsets;  // Discarded...
-          const Type *Ty = getStructOffsetType(ST, Offset, Offsets, false);
-          assert(Offset == 0 && "Offset changed from zero???");
-          if (!isFirstClassType(Ty)) return false;
-
-          // See if the leaf type is compatible with the old return type...
-          if (TD.getTypeSize(Ty) != TD.getTypeSize(LI->getType()))
-            return false;
+      
+      const Type *LoadedTy = PT->getElementType();
+
+      // They could be loading the first element of a composite type...
+      if (const CompositeType *CT = dyn_cast<CompositeType>(LoadedTy)) {
+        unsigned Offset = 0;     // No offset, get first leaf.
+        std::vector<Value*> Indices;  // Discarded...
+        LoadedTy = getStructOffsetType(CT, Offset, Indices, TD, false);
+        assert(Offset == 0 && "Offset changed from zero???");
+      }
 
-          return RetValConvertableToType(LI, Ty, CTMap);
-        }
+      if (!LoadedTy->isFirstClassType())
         return false;
-      }
 
-      if (TD.getTypeSize(PVTy) != TD.getTypeSize(LI->getType()))
+      if (TD.getTypeSize(LoadedTy) != TD.getTypeSize(LI->getType()))
         return false;
 
-      return RetValConvertableToType(LI, PVTy, CTMap);
+      return ValueConvertibleToType(LI, LoadedTy, CTMap, TD);
     }
     return false;
 
   case Instruction::Store: {
     StoreInst *SI = cast<StoreInst>(I);
-    if (SI->hasIndices()) return false;
 
     if (V == I->getOperand(0)) {
+      ValueTypeCache::iterator CTMI = CTMap.find(I->getOperand(1));
+      if (CTMI != CTMap.end()) {   // Operand #1 is in the table already?
+        // If so, check to see if it's Ty*, or, more importantly, if it is a
+        // pointer to a structure where the first element is a Ty... this code
+        // is necessary because we might be trying to change the source and
+        // destination type of the store (they might be related) and the dest
+        // pointer type might be a pointer to structure.  Below we allow pointer
+        // to structures where the 0th element is compatible with the value,
+        // now we have to support the symmetrical part of this.
+        //
+        const Type *ElTy = cast<PointerType>(CTMI->second)->getElementType();
+
+        // Already a pointer to what we want?  Trivially accept...
+        if (ElTy == Ty) return true;
+
+        // Tricky case now, if the destination is a pointer to structure,
+        // obviously the source is not allowed to be a structure (cannot copy
+        // a whole structure at a time), so the level raiser must be trying to
+        // store into the first field.  Check for this and allow it now:
+        //
+        if (const StructType *SElTy = dyn_cast<StructType>(ElTy)) {
+          unsigned Offset = 0;
+          std::vector<Value*> Indices;
+          ElTy = getStructOffsetType(ElTy, Offset, Indices, TD, false);
+          assert(Offset == 0 && "Offset changed!");
+          if (ElTy == 0)    // Element at offset zero in struct doesn't exist!
+            return false;   // Can only happen for {}*
+          
+          if (ElTy == Ty)   // Looks like the 0th element of structure is
+            return true;    // compatible!  Accept now!
+
+          // Otherwise we know that we can't work, so just stop trying now.
+          return false;
+        }
+      }
+
       // Can convert the store if we can convert the pointer operand to match
       // the new  value type...
-      return ExpressionConvertableToType(I->getOperand(1), PointerType::get(Ty),
-                                         CTMap);
+      return ExpressionConvertibleToType(I->getOperand(1), PointerType::get(Ty),
+                                         CTMap, TD);
     } else if (const PointerType *PT = dyn_cast<PointerType>(Ty)) {
-      if (isa<ArrayType>(PT->getValueType()))
-        return false;  // Avoid getDataSize on unsized array type!
+      const Type *ElTy = PT->getElementType();
       assert(V == I->getOperand(1));
 
+      if (isa<StructType>(ElTy)) {
+        // We can change the destination pointer if we can store our first
+        // argument into the first element of the structure...
+        //
+        unsigned Offset = 0;
+        std::vector<Value*> Indices;
+        ElTy = getStructOffsetType(ElTy, Offset, Indices, TD, false);
+        assert(Offset == 0 && "Offset changed!");
+        if (ElTy == 0)    // Element at offset zero in struct doesn't exist!
+          return false;   // Can only happen for {}*
+      }
+
       // Must move the same amount of data...
-      if (TD.getTypeSize(PT->getValueType()) != 
-          TD.getTypeSize(I->getOperand(0)->getType())) return false;
+      if (!ElTy->isSized() || 
+          TD.getTypeSize(ElTy) != TD.getTypeSize(I->getOperand(0)->getType()))
+        return false;
 
-      // Can convert store if the incoming value is convertable...
-      return ExpressionConvertableToType(I->getOperand(0), PT->getValueType(),
-                                         CTMap);
+      // Can convert store if the incoming value is convertible and if the
+      // result will preserve semantics...
+      const Type *Op0Ty = I->getOperand(0)->getType();
+      if (!(Op0Ty->isIntegral() ^ ElTy->isIntegral()) &&
+          !(Op0Ty->isFloatingPoint() ^ ElTy->isFloatingPoint()))
+        return ExpressionConvertibleToType(I->getOperand(0), ElTy, CTMap, TD);
     }
     return false;
   }
 
-  case Instruction::PHINode: {
+  case Instruction::GetElementPtr:
+    if (V != I->getOperand(0) || !isa<PointerType>(Ty)) return false;
+
+    // If we have a two operand form of getelementptr, this is really little
+    // more than a simple addition.  As with addition, check to see if the
+    // getelementptr instruction can be changed to index into the new type.
+    //
+    if (I->getNumOperands() == 2) {
+      const Type *OldElTy = cast<PointerType>(I->getType())->getElementType();
+      unsigned DataSize = TD.getTypeSize(OldElTy);
+      Value *Index = I->getOperand(1);
+      Instruction *TempScale = 0;
+
+      // If the old data element is not unit sized, we have to create a scale
+      // instruction so that ConvertibleToGEP will know the REAL amount we are
+      // indexing by.  Note that this is never inserted into the instruction
+      // stream, so we have to delete it when we're done.
+      //
+      if (DataSize != 1) {
+        Value *CST;
+        if (Index->getType()->isSigned())
+          CST = ConstantSInt::get(Index->getType(), DataSize);
+        else
+          CST = ConstantUInt::get(Index->getType(), DataSize);
+                                  
+        TempScale = BinaryOperator::create(Instruction::Mul, Index, CST);
+        Index = TempScale;
+      }
+
+      // Check to see if the second argument is an expression that can
+      // be converted to the appropriate size... if so, allow it.
+      //
+      std::vector<Value*> Indices;
+      const Type *ElTy = ConvertibleToGEP(Ty, Index, Indices, TD);
+      delete TempScale;   // Free our temporary multiply if we made it
+
+      if (ElTy == 0) return false;  // Cannot make conversion...
+      return ValueConvertibleToType(I, PointerType::get(ElTy), CTMap, TD);
+    }
+    return false;
+
+  case Instruction::PHI: {
     PHINode *PN = cast<PHINode>(I);
+    // Be conservative if we find a giant PHI node.
+    if (PN->getNumIncomingValues() > 32) return false;
+
     for (unsigned i = 0; i < PN->getNumIncomingValues(); ++i)
-      if (!ExpressionConvertableToType(PN->getIncomingValue(i), Ty, CTMap))
+      if (!ExpressionConvertibleToType(PN->getIncomingValue(i), Ty, CTMap, TD))
         return false;
-    return RetValConvertableToType(PN, Ty, CTMap);
+    return ValueConvertibleToType(PN, Ty, CTMap, TD);
   }
 
-#if 0
-  case Instruction::GetElementPtr: {
-    // GetElementPtr's are directly convertable to a pointer type if they have
-    // a number of zeros at the end.  Because removing these values does not
-    // change the logical offset of the GEP, it is okay and fair to remove them.
-    // This can change this:
-    //   %t1 = getelementptr %Hosp * %hosp, ubyte 4, ubyte 0  ; <%List **>
-    //   %t2 = cast %List * * %t1 to %List *
-    // into
-    //   %t2 = getelementptr %Hosp * %hosp, ubyte 4           ; <%List *>
-    // 
-    GetElementPtrInst *GEP = cast<GetElementPtrInst>(I);
-    const PointerType *PTy = dyn_cast<PointerType>(Ty);
-    if (!PTy) return false;
+  case Instruction::Call: {
+    User::op_iterator OI = find(I->op_begin(), I->op_end(), V);
+    assert (OI != I->op_end() && "Not using value!");
+    unsigned OpNum = OI - I->op_begin();
 
-    // Check to see if there are zero elements that we can remove from the
-    // index array.  If there are, check to see if removing them causes us to
-    // get to the right type...
-    //
-    vector<ConstPoolVal*> Indices = GEP->getIndices();
-    const Type *BaseType = GEP->getPtrOperand()->getType();
+    // Are we trying to change the function pointer value to a new type?
+    if (OpNum == 0) {
+      const PointerType *PTy = dyn_cast<PointerType>(Ty);
+      if (PTy == 0) return false;  // Can't convert to a non-pointer type...
+      const FunctionType *FTy = dyn_cast<FunctionType>(PTy->getElementType());
+      if (FTy == 0) return false;  // Can't convert to a non ptr to function...
 
-    while (Indices.size() &&
-           cast<ConstPoolUInt>(Indices.back())->getValue() == 0) {
-      Indices.pop_back();
-      const Type *ElTy = GetElementPtrInst::getIndexedType(BaseType, Indices,
-                                                           true);
-      if (ElTy == PTy->getValueType())
-        return true;  // Found a match!!
+      // Do not allow converting to a call where all of the operands are ...'s
+      if (FTy->getNumParams() == 0 && FTy->isVarArg())
+        return false;              // Do not permit this conversion!
+
+      // Perform sanity checks to make sure that new function type has the
+      // correct number of arguments...
+      //
+      unsigned NumArgs = I->getNumOperands()-1;  // Don't include function ptr
+
+      // Cannot convert to a type that requires more fixed arguments than
+      // the call provides...
+      //
+      if (NumArgs < FTy->getNumParams()) return false;
+      
+      // Unless this is a vararg function type, we cannot provide more arguments
+      // than are desired...
+      //
+      if (!FTy->isVarArg() && NumArgs > FTy->getNumParams())
+        return false;
+
+      // Okay, at this point, we know that the call and the function type match
+      // number of arguments.  Now we see if we can convert the arguments
+      // themselves.  Note that we do not require operands to be convertible,
+      // we can insert casts if they are convertible but not compatible.  The
+      // reason for this is that we prefer to have resolved functions but casted
+      // arguments if possible.
+      //
+      for (unsigned i = 0, NA = FTy->getNumParams(); i < NA; ++i)
+        if (!FTy->getParamType(i)->isLosslesslyConvertibleTo(I->getOperand(i+1)->getType()))
+          return false;   // Operands must have compatible types!
+
+      // Okay, at this point, we know that all of the arguments can be
+      // converted.  We succeed if we can change the return type if
+      // necessary...
+      //
+      return ValueConvertibleToType(I, FTy->getReturnType(), CTMap, TD);
     }
-    break;   // No match, maybe next time.
+    
+    const PointerType *MPtr = cast<PointerType>(I->getOperand(0)->getType());
+    const FunctionType *FTy = cast<FunctionType>(MPtr->getElementType());
+    if (!FTy->isVarArg()) return false;
+
+    if ((OpNum-1) < FTy->getNumParams())
+      return false;  // It's not in the varargs section...
+
+    // If we get this far, we know the value is in the varargs section of the
+    // function!  We can convert if we don't reinterpret the value...
+    //
+    return Ty->isLosslesslyConvertibleTo(V->getType());
   }
-#endif
   }
   return false;
 }
 
 
-void ConvertUsersType(Value *V, Value *NewVal, ValueMapCache &VMC) {
-  ValueHandle VH(V);
+void llvm::ConvertValueToNewType(Value *V, Value *NewVal, ValueMapCache &VMC,
+                                 const TargetData &TD) {
+  ValueHandle VH(VMC, V);
 
   unsigned NumUses = V->use_size();
   for (unsigned It = 0; It < NumUses; ) {
     unsigned OldSize = NumUses;
-    ConvertOperandToType(*(V->use_begin()+It), V, NewVal, VMC);
+    Value::use_iterator UI = V->use_begin();
+    std::advance(UI, It);
+    ConvertOperandToType(*UI, V, NewVal, VMC, TD);
     NumUses = V->use_size();
     if (NumUses == OldSize) ++It;
   }
@@ -525,7 +912,7 @@ void ConvertUsersType(Value *V, Value *NewVal, ValueMapCache &VMC) {
 
 
 static void ConvertOperandToType(User *U, Value *OldVal, Value *NewVal,
-                                 ValueMapCache &VMC) {
+                                 ValueMapCache &VMC, const TargetData &TD) {
   if (isa<ValueHandle>(U)) return;  // Valuehandles don't let go of operands...
 
   if (VMC.OperandsMapped.count(U)) return;
@@ -536,35 +923,53 @@ static void ConvertOperandToType(User *U, Value *OldVal, Value *NewVal,
     return;
 
 
-  Instruction *I = cast<Instruction>(U);  // Only Instructions convertable
+  Instruction *I = cast<Instruction>(U);  // Only Instructions convertible
 
   BasicBlock *BB = I->getParent();
-  BasicBlock::InstListType &BIL = BB->getInstList();
-  string Name = I->getName();  if (!Name.empty()) I->setName("");
+  assert(BB != 0 && "Instruction not embedded in basic block!");
+  std::string Name = I->getName();
+  I->setName("");
   Instruction *Res;     // Result of conversion
 
-  //cerr << endl << endl << "Type:\t" << Ty << "\nInst: " << I << "BB Before: " << BB << endl;
+  //std::cerr << endl << endl << "Type:\t" << Ty << "\nInst: " << I
+  //          << "BB Before: " << BB << endl;
 
   // Prevent I from being removed...
-  ValueHandle IHandle(I);
+  ValueHandle IHandle(VMC, I);
 
   const Type *NewTy = NewVal->getType();
-  ConstPoolVal *Dummy = (NewTy != Type::VoidTy) ? 
-                  ConstPoolVal::getNullConstant(NewTy) : 0;
+  Constant *Dummy = (NewTy != Type::VoidTy) ? 
+                  Constant::getNullValue(NewTy) : 0;
 
   switch (I->getOpcode()) {
   case Instruction::Cast:
-    assert(I->getOperand(0) == OldVal);
-    Res = new CastInst(NewVal, I->getType(), Name);
+    if (VMC.NewCasts.count(ValueHandle(VMC, I))) {
+      // This cast has already had it's value converted, causing a new cast to
+      // be created.  We don't want to create YET ANOTHER cast instruction
+      // representing the original one, so just modify the operand of this cast
+      // instruction, which we know is newly created.
+      I->setOperand(0, NewVal);
+      I->setName(Name);  // give I its name back
+      return;
+
+    } else {
+      Res = new CastInst(NewVal, I->getType(), Name);
+    }
     break;
 
   case Instruction::Add:
-    if (OldVal == I->getOperand(0) && isa<CastInst>(I->getOperand(1))) {
-      Res = getAddToGEPResult(NewVal->getType(),
-                              cast<CastInst>(I->getOperand(1))->getOperand(0));
-      if (Res) {  // If successful, this Add should be converted to a GEP.
+    if (isa<PointerType>(NewTy)) {
+      Value *IndexVal = I->getOperand(OldVal == I->getOperand(0) ? 1 : 0);
+      std::vector<Value*> Indices;
+      BasicBlock::iterator It = I;
+
+      if (const Type *ETy = ConvertibleToGEP(NewTy, IndexVal, Indices, TD,&It)){
+        // If successful, convert the add to a GEP
+        //const Type *RetTy = PointerType::get(ETy);
         // First operand is actually the given pointer...
-        Res->setOperand(0, NewVal);
+        Res = new GetElementPtrInst(NewVal, Indices, Name);
+        assert(cast<PointerType>(Res->getType())->getElementType() == ETy &&
+               "ConvertibleToGEP broken!");
         break;
       }
     }
@@ -579,7 +984,7 @@ static void ConvertOperandToType(User *U, Value *OldVal, Value *NewVal,
 
     unsigned OtherIdx = (OldVal == I->getOperand(0)) ? 1 : 0;
     Value *OtherOp    = I->getOperand(OtherIdx);
-    Value *NewOther   = ConvertExpressionToType(OtherOp, NewTy, VMC);
+    Value *NewOther   = ConvertExpressionToType(OtherOp, NewTy, VMC, TD);
 
     Res->setOperand(OtherIdx, NewOther);
     Res->setOperand(!OtherIdx, NewVal);
@@ -592,37 +997,165 @@ static void ConvertOperandToType(User *U, Value *OldVal, Value *NewVal,
                         I->getOperand(1), Name);
     break;
 
+  case Instruction::Free:            // Free can free any pointer type!
+    assert(I->getOperand(0) == OldVal);
+    Res = new FreeInst(NewVal);
+    break;
+
+
   case Instruction::Load: {
     assert(I->getOperand(0) == OldVal && isa<PointerType>(NewVal->getType()));
-    const Type *PVTy = cast<PointerType>(NewVal->getType())->getValueType();
-    if (!isFirstClassType(PVTy)) {  // Must be an indirect load then...
-      assert(isa<StructType>(PVTy));
+    const Type *LoadedTy =
+      cast<PointerType>(NewVal->getType())->getElementType();
+
+    Value *Src = NewVal;
+
+    if (const CompositeType *CT = dyn_cast<CompositeType>(LoadedTy)) {
+      std::vector<Value*> Indices;
+      Indices.push_back(Constant::getNullValue(Type::UIntTy));
+
       unsigned Offset = 0;   // No offset, get first leaf.
-      vector<ConstPoolVal*> Offsets;  // Discarded...
-      const Type *Ty = getStructOffsetType(PVTy, Offset, Offsets, false);
-      Res = new LoadInst(NewVal, Offsets, Name);
-    } else {
-      Res = new LoadInst(NewVal, Name);
+      LoadedTy = getStructOffsetType(CT, Offset, Indices, TD, false);
+      assert(LoadedTy->isFirstClassType());
+
+      if (Indices.size() != 1) {     // Do not generate load X, 0
+        // Insert the GEP instruction before this load.
+        Src = new GetElementPtrInst(Src, Indices, Name+".idx", I);
+      }
     }
-    assert(isFirstClassType(Res->getType()) && "Load of structure or array!");
+    
+    Res = new LoadInst(Src, Name);
+    assert(Res->getType()->isFirstClassType() && "Load of structure or array!");
     break;
   }
+
   case Instruction::Store: {
     if (I->getOperand(0) == OldVal) {  // Replace the source value
-      const PointerType *NewPT = PointerType::get(NewTy);
-      Res = new StoreInst(NewVal, ConstPoolVal::getNullConstant(NewPT));
-      VMC.ExprMap[I] = Res;
-      Res->setOperand(1, ConvertExpressionToType(I->getOperand(1), NewPT, VMC));
+      // Check to see if operand #1 has already been converted...
+      ValueMapCache::ExprMapTy::iterator VMCI =
+        VMC.ExprMap.find(I->getOperand(1));
+      if (VMCI != VMC.ExprMap.end()) {
+        // Comments describing this stuff are in the OperandConvertibleToType
+        // switch statement for Store...
+        //
+        const Type *ElTy =
+          cast<PointerType>(VMCI->second->getType())->getElementType();
+        
+        Value *SrcPtr = VMCI->second;
+
+        if (ElTy != NewTy) {
+          // We check that this is a struct in the initial scan...
+          const StructType *SElTy = cast<StructType>(ElTy);
+          
+          std::vector<Value*> Indices;
+          Indices.push_back(Constant::getNullValue(Type::UIntTy));
+
+          unsigned Offset = 0;
+          const Type *Ty = getStructOffsetType(ElTy, Offset, Indices, TD,false);
+          assert(Offset == 0 && "Offset changed!");
+          assert(NewTy == Ty && "Did not convert to correct type!");
+
+          // Insert the GEP instruction before this store.
+          SrcPtr = new GetElementPtrInst(SrcPtr, Indices,
+                                         SrcPtr->getName()+".idx", I);
+        }
+        Res = new StoreInst(NewVal, SrcPtr);
+
+        VMC.ExprMap[I] = Res;
+      } else {
+        // Otherwise, we haven't converted Operand #1 over yet...
+        const PointerType *NewPT = PointerType::get(NewTy);
+        Res = new StoreInst(NewVal, Constant::getNullValue(NewPT));
+        VMC.ExprMap[I] = Res;
+        Res->setOperand(1, ConvertExpressionToType(I->getOperand(1),
+                                                   NewPT, VMC, TD));
+      }
     } else {                           // Replace the source pointer
-      const Type *ValTy = cast<PointerType>(NewTy)->getValueType();
-      Res = new StoreInst(ConstPoolVal::getNullConstant(ValTy), NewVal);
+      const Type *ValTy = cast<PointerType>(NewTy)->getElementType();
+
+      Value *SrcPtr = NewVal;
+
+      if (isa<StructType>(ValTy)) {
+        std::vector<Value*> Indices;
+        Indices.push_back(Constant::getNullValue(Type::UIntTy));
+
+        unsigned Offset = 0;
+        ValTy = getStructOffsetType(ValTy, Offset, Indices, TD, false);
+
+        assert(Offset == 0 && ValTy);
+
+        // Insert the GEP instruction before this store.
+        SrcPtr = new GetElementPtrInst(SrcPtr, Indices,
+                                       SrcPtr->getName()+".idx", I);
+      }
+
+      Res = new StoreInst(Constant::getNullValue(ValTy), SrcPtr);
       VMC.ExprMap[I] = Res;
-      Res->setOperand(0, ConvertExpressionToType(I->getOperand(0), ValTy, VMC));
+      Res->setOperand(0, ConvertExpressionToType(I->getOperand(0),
+                                                 ValTy, VMC, TD));
     }
     break;
   }
 
-  case Instruction::PHINode: {
+
+  case Instruction::GetElementPtr: {
+    // Convert a one index getelementptr into just about anything that is
+    // desired.
+    //
+    BasicBlock::iterator It = I;
+    const Type *OldElTy = cast<PointerType>(I->getType())->getElementType();
+    unsigned DataSize = TD.getTypeSize(OldElTy);
+    Value *Index = I->getOperand(1);
+
+    if (DataSize != 1) {
+      // Insert a multiply of the old element type is not a unit size...
+      Value *CST;
+      if (Index->getType()->isSigned())
+        CST = ConstantSInt::get(Index->getType(), DataSize);
+      else
+        CST = ConstantUInt::get(Index->getType(), DataSize);
+
+      Index = BinaryOperator::create(Instruction::Mul, Index, CST, "scale", It);
+    }
+
+    // Perform the conversion now...
+    //
+    std::vector<Value*> Indices;
+    const Type *ElTy = ConvertibleToGEP(NewVal->getType(),Index,Indices,TD,&It);
+    assert(ElTy != 0 && "GEP Conversion Failure!");
+    Res = new GetElementPtrInst(NewVal, Indices, Name);
+    assert(Res->getType() == PointerType::get(ElTy) &&
+           "ConvertibleToGet failed!");
+  }
+#if 0
+    if (I->getType() == PointerType::get(Type::SByteTy)) {
+      // Convert a getelementptr sbyte * %reg111, uint 16 freely back to
+      // anything that is a pointer type...
+      //
+      BasicBlock::iterator It = I;
+    
+      // Check to see if the second argument is an expression that can
+      // be converted to the appropriate size... if so, allow it.
+      //
+      std::vector<Value*> Indices;
+      const Type *ElTy = ConvertibleToGEP(NewVal->getType(), I->getOperand(1),
+                                          Indices, TD, &It);
+      assert(ElTy != 0 && "GEP Conversion Failure!");
+      
+      Res = new GetElementPtrInst(NewVal, Indices, Name);
+    } else {
+      // Convert a getelementptr ulong * %reg123, uint %N
+      // to        getelementptr  long * %reg123, uint %N
+      // ... where the type must simply stay the same size...
+      //
+      GetElementPtrInst *GEP = cast<GetElementPtrInst>(I);
+      std::vector<Value*> Indices(GEP->idx_begin(), GEP->idx_end());
+      Res = new GetElementPtrInst(NewVal, Indices, Name);
+    }
+#endif
+    break;
+
+  case Instruction::PHI: {
     PHINode *OldPN = cast<PHINode>(I);
     PHINode *NewPN = new PHINode(NewTy, Name);
     VMC.ExprMap[I] = NewPN;
@@ -630,130 +1163,136 @@ static void ConvertOperandToType(User *U, Value *OldVal, Value *NewVal,
     while (OldPN->getNumOperands()) {
       BasicBlock *BB = OldPN->getIncomingBlock(0);
       Value *OldVal = OldPN->getIncomingValue(0);
-      OldPN->removeIncomingValue(BB);
-      Value *V = ConvertExpressionToType(OldVal, NewTy, VMC);
+      ValueHandle OldValHandle(VMC, OldVal);
+      OldPN->removeIncomingValue(BB, false);
+      Value *V = ConvertExpressionToType(OldVal, NewTy, VMC, TD);
       NewPN->addIncoming(V, BB);
     }
     Res = NewPN;
     break;
   }
 
-#if 0
-  case Instruction::GetElementPtr: {
-    // GetElementPtr's are directly convertable to a pointer type if they have
-    // a number of zeros at the end.  Because removing these values does not
-    // change the logical offset of the GEP, it is okay and fair to remove them.
-    // This can change this:
-    //   %t1 = getelementptr %Hosp * %hosp, ubyte 4, ubyte 0  ; <%List **>
-    //   %t2 = cast %List * * %t1 to %List *
-    // into
-    //   %t2 = getelementptr %Hosp * %hosp, ubyte 4           ; <%List *>
-    // 
-    GetElementPtrInst *GEP = cast<GetElementPtrInst>(I);
+  case Instruction::Call: {
+    Value *Meth = I->getOperand(0);
+    std::vector<Value*> Params(I->op_begin()+1, I->op_end());
 
-    // Check to see if there are zero elements that we can remove from the
-    // index array.  If there are, check to see if removing them causes us to
-    // get to the right type...
-    //
-    vector<ConstPoolVal*> Indices = GEP->getIndices();
-    const Type *BaseType = GEP->getPtrOperand()->getType();
-    const Type *PVTy = cast<PointerType>(Ty)->getValueType();
-    Res = 0;
-    while (Indices.size() &&
-           cast<ConstPoolUInt>(Indices.back())->getValue() == 0) {
-      Indices.pop_back();
-      if (GetElementPtrInst::getIndexedType(BaseType, Indices, true) == PVTy) {
-        if (Indices.size() == 0) {
-          Res = new CastInst(GEP->getPtrOperand(), BaseType); // NOOP
-        } else {
-          Res = new GetElementPtrInst(GEP->getPtrOperand(), Indices, Name);
+    if (Meth == OldVal) {   // Changing the function pointer?
+      const PointerType *NewPTy = cast<PointerType>(NewVal->getType());
+      const FunctionType *NewTy = cast<FunctionType>(NewPTy->getElementType());
+
+      if (NewTy->getReturnType() == Type::VoidTy)
+        Name = "";  // Make sure not to name a void call!
+
+      // Get an iterator to the call instruction so that we can insert casts for
+      // operands if need be.  Note that we do not require operands to be
+      // convertible, we can insert casts if they are convertible but not
+      // compatible.  The reason for this is that we prefer to have resolved
+      // functions but casted arguments if possible.
+      //
+      BasicBlock::iterator It = I;
+
+      // Convert over all of the call operands to their new types... but only
+      // convert over the part that is not in the vararg section of the call.
+      //
+      for (unsigned i = 0; i != NewTy->getNumParams(); ++i)
+        if (Params[i]->getType() != NewTy->getParamType(i)) {
+          // Create a cast to convert it to the right type, we know that this
+          // is a lossless cast...
+          //
+          Params[i] = new CastInst(Params[i], NewTy->getParamType(i),
+                                   "callarg.cast." +
+                                   Params[i]->getName(), It);
         }
-        break;
-      }
+      Meth = NewVal;  // Update call destination to new value
+
+    } else {                   // Changing an argument, must be in vararg area
+      std::vector<Value*>::iterator OI =
+        find(Params.begin(), Params.end(), OldVal);
+      assert (OI != Params.end() && "Not using value!");
+
+      *OI = NewVal;
     }
-    assert(Res && "Didn't find match!");
-    break;   // No match, maybe next time.
-  }
-#endif
 
+    Res = new CallInst(Meth, Params, Name);
+    break;
+  }
   default:
-    assert(0 && "Expression convertable, but don't know how to convert?");
+    assert(0 && "Expression convertible, but don't know how to convert?");
     return;
   }
 
-  BasicBlock::iterator It = find(BIL.begin(), BIL.end(), I);
-  assert(It != BIL.end() && "Instruction not in own basic block??");
-  BIL.insert(It, Res);   // Keep It pointing to old instruction
+  // If the instruction was newly created, insert it into the instruction
+  // stream.
+  //
+  BasicBlock::iterator It = I;
+  assert(It != BB->end() && "Instruction not in own basic block??");
+  BB->getInstList().insert(It, Res);   // Keep It pointing to old instruction
 
-#ifdef DEBUG_EXPR_CONVERT
-  cerr << "COT CREATED: "  << (void*)Res << " " << Res;
-  cerr << "In: " << (void*)I << " " << I << "Out: " << (void*)Res << " " << Res;
-#endif
+  DEBUG(std::cerr << "COT CREATED: "  << (void*)Res << " " << *Res
+                  << "In: " << (void*)I << " " << *I << "Out: " << (void*)Res
+                  << " " << *Res);
 
   // Add the instruction to the expression map
   VMC.ExprMap[I] = Res;
 
   if (I->getType() != Res->getType())
-    ConvertUsersType(I, Res, VMC);
+    ConvertValueToNewType(I, Res, VMC, TD);
   else {
-    for (unsigned It = 0; It < I->use_size(); ) {
-      User *Use = *(I->use_begin()+It);
-      if (isa<ValueHandle>(Use))            // Don't remove ValueHandles!
-        ++It;
-      else
-        Use->replaceUsesOfWith(I, Res);
-    }
-
-    if (I->use_empty()) {
-      // Now we just need to remove the old instruction so we don't get infinite
-      // loops.  Note that we cannot use DCE because DCE won't remove a store
-      // instruction, for example.
-      //
-#ifdef DEBUG_EXPR_CONVERT
-      cerr << "DELETING: " << (void*)I << " " << I;
-#endif
-      BIL.remove(I);
-      delete I;
-    } else {
-      for (Value::use_iterator UI = I->use_begin(), UE = I->use_end();
-           UI != UE; ++UI)
-        assert(isa<ValueHandle>((Value*)*UI) && "Uses of Instruction remain!!!");
+    bool FromStart = true;
+    Value::use_iterator UI;
+    while (1) {
+      if (FromStart) UI = I->use_begin();
+      if (UI == I->use_end()) break;
+      
+      if (isa<ValueHandle>(*UI)) {
+        ++UI;
+        FromStart = false;
+      } else {
+        User *U = *UI;
+        if (!FromStart) --UI;
+        U->replaceUsesOfWith(I, Res);
+        if (!FromStart) ++UI;
+      }
     }
   }
 }
 
-ValueHandle::ValueHandle(Value *V) : Instruction(Type::VoidTy, UserOp1, "") {
-#ifdef DEBUG_EXPR_CONVERT
-  cerr << "VH AQUIRING: " << (void*)V << " " << V;
-#endif
+
+ValueHandle::ValueHandle(ValueMapCache &VMC, Value *V)
+  : Instruction(Type::VoidTy, UserOp1, ""), Cache(VMC) {
+  //DEBUG(std::cerr << "VH AQUIRING: " << (void*)V << " " << V);
   Operands.push_back(Use(V, this));
 }
 
-static void RecursiveDelete(Instruction *I) {
+ValueHandle::ValueHandle(const ValueHandle &VH)
+  : Instruction(Type::VoidTy, UserOp1, ""), Cache(VH.Cache) {
+  //DEBUG(std::cerr << "VH AQUIRING: " << (void*)V << " " << V);
+  Operands.push_back(Use((Value*)VH.getOperand(0), this));
+}
+
+static void RecursiveDelete(ValueMapCache &Cache, Instruction *I) {
   if (!I || !I->use_empty()) return;
 
   assert(I->getParent() && "Inst not in basic block!");
 
-#ifdef DEBUG_EXPR_CONVERT
-  cerr << "VH DELETING: " << (void*)I << " " << I;
-#endif
+  //DEBUG(std::cerr << "VH DELETING: " << (void*)I << " " << I);
 
   for (User::op_iterator OI = I->op_begin(), OE = I->op_end(); 
-       OI != OE; ++OI) {
-    Instruction *U = dyn_cast<Instruction>(*OI);
-    if (U) {
+       OI != OE; ++OI)
+    if (Instruction *U = dyn_cast<Instruction>(OI)) {
       *OI = 0;
-      RecursiveDelete(dyn_cast<Instruction>(U));
+      RecursiveDelete(Cache, U);
     }
-  }
 
   I->getParent()->getInstList().remove(I);
+
+  Cache.OperandsMapped.erase(I);
+  Cache.ExprMap.erase(I);
   delete I;
 }
 
-
 ValueHandle::~ValueHandle() {
-  if (Operands[0]->use_size() == 1) {
+  if (Operands[0]->hasOneUse()) {
     Value *V = Operands[0];
     Operands[0] = 0;   // Drop use!
 
@@ -761,10 +1300,10 @@ ValueHandle::~ValueHandle() {
     // loops.  Note that we cannot use DCE because DCE won't remove a store
     // instruction, for example.
     //
-    RecursiveDelete(dyn_cast<Instruction>(V));
+    RecursiveDelete(Cache, dyn_cast<Instruction>(V));
   } else {
-#ifdef DEBUG_EXPR_CONVERT
-    cerr << "VH RELEASING: " << (void*)Operands[0].get() << " " << Operands[0]->use_size() << " " << Operands[0];
-#endif
+    //DEBUG(std::cerr << "VH RELEASING: " << (void*)Operands[0].get() << " "
+    //                << Operands[0]->use_size() << " " << Operands[0]);
   }
 }
+