lib/ExecutionEngine/ExecutionEngine.cpp - fp2-dev/platform/external/llvm - Gitiles

 //===-- ExecutionEngine.cpp - Common Implementation shared by EEs ---------===//
 //
 //                     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 defines the common interface used by the various execution engine
 // subclasses.
 //
 //===----------------------------------------------------------------------===//

 #define DEBUG_TYPE "jit"
 #include "Interpreter/Interpreter.h"
 #include "JIT/JIT.h"
 #include "llvm/Constants.h"
 #include "llvm/DerivedTypes.h"
 #include "llvm/Module.h"
 #include "llvm/ModuleProvider.h"
 #include "llvm/ExecutionEngine/ExecutionEngine.h"
 #include "llvm/ExecutionEngine/GenericValue.h"
 #include "llvm/Target/TargetData.h"
 #include "Support/Debug.h"
 #include "Support/Statistic.h"
 #include "Support/DynamicLinker.h"
 #include "Config/dlfcn.h"
 using namespace llvm;

 namespace {
   Statistic<> NumInitBytes("lli", "Number of bytes of global vars initialized");
 }

 ExecutionEngine::ExecutionEngine(ModuleProvider *P) :
   CurMod(*P->getModule()), MP(P) {
   assert(P && "ModuleProvider is null?");
 }

 ExecutionEngine::ExecutionEngine(Module *M) : CurMod(*M), MP(0) {
   assert(M && "Module is null?");
 }

 ExecutionEngine::~ExecutionEngine() {
   delete MP;
 }

 /// If possible, create a JIT, unless the caller specifically requests an
 /// Interpreter or there's an error. If even an Interpreter cannot be created,
 /// NULL is returned.
 ///
 ExecutionEngine *ExecutionEngine::create(ModuleProvider *MP,
                                          bool ForceInterpreter) {
   ExecutionEngine *EE = 0;

   // Unless the interpreter was explicitly selected, make a JIT.
   if (!ForceInterpreter)
     EE = JIT::create(MP);

   // If we can't make a JIT, make an interpreter instead.
   try {
     if (EE == 0)
       EE = Interpreter::create(MP->materializeModule());
   } catch (...) {
     EE = 0;
   }
   return EE;
 }

 /// getPointerToGlobal - This returns the address of the specified global
 /// value.  This may involve code generation if it's a function.
 ///
 void *ExecutionEngine::getPointerToGlobal(const GlobalValue *GV) {
   if (Function *F = const_cast<Function*>(dyn_cast<Function>(GV)))
     return getPointerToFunction(F);

   assert(GlobalAddress[GV] && "Global hasn't had an address allocated yet?");
   return GlobalAddress[GV];
 }

 /// FIXME: document
 ///
 GenericValue ExecutionEngine::getConstantValue(const Constant *C) {
   GenericValue Result;

   if (ConstantExpr *CE = const_cast<ConstantExpr*>(dyn_cast<ConstantExpr>(C))) {
     switch (CE->getOpcode()) {
     case Instruction::GetElementPtr: {
       Result = getConstantValue(CE->getOperand(0));
       std::vector<Value*> Indexes(CE->op_begin()+1, CE->op_end());
       uint64_t Offset =
         TD->getIndexedOffset(CE->getOperand(0)->getType(), Indexes);

       Result.LongVal += Offset;
       return Result;
     }
     case Instruction::Cast: {
       // We only need to handle a few cases here.  Almost all casts will
       // automatically fold, just the ones involving pointers won't.
       //
       Constant *Op = CE->getOperand(0);

       // Handle cast of pointer to pointer...
       if (Op->getType()->getPrimitiveID() == C->getType()->getPrimitiveID())
         return getConstantValue(Op);

       // Handle a cast of pointer to any integral type...
       if (isa<PointerType>(Op->getType()) && C->getType()->isIntegral())
         return getConstantValue(Op);

       // Handle cast of long to pointer...
       if (isa<PointerType>(C->getType()) && (Op->getType() == Type::LongTy ||
                                              Op->getType() == Type::ULongTy))
         return getConstantValue(Op);
       break;
     }

     case Instruction::Add:
       if (CE->getOperand(0)->getType() == Type::LongTy ||
           CE->getOperand(0)->getType() == Type::ULongTy)
         Result.LongVal = getConstantValue(CE->getOperand(0)).LongVal +
                          getConstantValue(CE->getOperand(1)).LongVal;
       else
         break;
       return Result;

     default:
       break;
     }
     std::cerr << "ConstantExpr not handled as global var init: " << *CE << "\n";
     abort();
   }

   switch (C->getType()->getPrimitiveID()) {
 #define GET_CONST_VAL(TY, CLASS) \
   case Type::TY##TyID: Result.TY##Val = cast<CLASS>(C)->getValue(); break
     GET_CONST_VAL(Bool   , ConstantBool);
     GET_CONST_VAL(UByte  , ConstantUInt);
     GET_CONST_VAL(SByte  , ConstantSInt);
     GET_CONST_VAL(UShort , ConstantUInt);
     GET_CONST_VAL(Short  , ConstantSInt);
     GET_CONST_VAL(UInt   , ConstantUInt);
     GET_CONST_VAL(Int    , ConstantSInt);
     GET_CONST_VAL(ULong  , ConstantUInt);
     GET_CONST_VAL(Long   , ConstantSInt);
     GET_CONST_VAL(Float  , ConstantFP);
     GET_CONST_VAL(Double , ConstantFP);
 #undef GET_CONST_VAL
   case Type::PointerTyID:
     if (isa<ConstantPointerNull>(C)) {
       Result.PointerVal = 0;
     } else if (const ConstantPointerRef *CPR = dyn_cast<ConstantPointerRef>(C)){
       if (Function *F =
           const_cast<Function*>(dyn_cast<Function>(CPR->getValue())))
         Result = PTOGV(getPointerToFunctionOrStub(F));
       else
         Result = PTOGV(getPointerToGlobal(CPR->getValue()));

     } else {
       assert(0 && "Unknown constant pointer type!");
     }
     break;
   default:
     std::cout << "ERROR: Constant unimp for type: " << C->getType() << "\n";
     abort();
   }
   return Result;
 }

 /// FIXME: document
 ///
 void ExecutionEngine::StoreValueToMemory(GenericValue Val, GenericValue *Ptr,
                                          const Type *Ty) {
   if (getTargetData().isLittleEndian()) {
     switch (Ty->getPrimitiveID()) {
     case Type::BoolTyID:
     case Type::UByteTyID:
     case Type::SByteTyID:   Ptr->Untyped[0] = Val.UByteVal; break;
     case Type::UShortTyID:
     case Type::ShortTyID:   Ptr->Untyped[0] = Val.UShortVal & 255;
                             Ptr->Untyped[1] = (Val.UShortVal >> 8) & 255;
                             break;
     Store4BytesLittleEndian:
     case Type::FloatTyID:
     case Type::UIntTyID:
     case Type::IntTyID:     Ptr->Untyped[0] =  Val.UIntVal        & 255;
                             Ptr->Untyped[1] = (Val.UIntVal >>  8) & 255;
                             Ptr->Untyped[2] = (Val.UIntVal >> 16) & 255;
                             Ptr->Untyped[3] = (Val.UIntVal >> 24) & 255;
                             break;
     case Type::PointerTyID: if (getTargetData().getPointerSize() == 4)
                               goto Store4BytesLittleEndian;
     case Type::DoubleTyID:
     case Type::ULongTyID:
     case Type::LongTyID:    Ptr->Untyped[0] =  Val.ULongVal        & 255;
                             Ptr->Untyped[1] = (Val.ULongVal >>  8) & 255;
                             Ptr->Untyped[2] = (Val.ULongVal >> 16) & 255;
                             Ptr->Untyped[3] = (Val.ULongVal >> 24) & 255;
                             Ptr->Untyped[4] = (Val.ULongVal >> 32) & 255;
                             Ptr->Untyped[5] = (Val.ULongVal >> 40) & 255;
                             Ptr->Untyped[6] = (Val.ULongVal >> 48) & 255;
                             Ptr->Untyped[7] = (Val.ULongVal >> 56) & 255;
                             break;
     default:
       std::cout << "Cannot store value of type " << Ty << "!\n";
     }
   } else {
     switch (Ty->getPrimitiveID()) {
     case Type::BoolTyID:
     case Type::UByteTyID:
     case Type::SByteTyID:   Ptr->Untyped[0] = Val.UByteVal; break;
     case Type::UShortTyID:
     case Type::ShortTyID:   Ptr->Untyped[1] = Val.UShortVal & 255;
                             Ptr->Untyped[0] = (Val.UShortVal >> 8) & 255;
                             break;
     Store4BytesBigEndian:
     case Type::FloatTyID:
     case Type::UIntTyID:
     case Type::IntTyID:     Ptr->Untyped[3] =  Val.UIntVal        & 255;
                             Ptr->Untyped[2] = (Val.UIntVal >>  8) & 255;
                             Ptr->Untyped[1] = (Val.UIntVal >> 16) & 255;
                             Ptr->Untyped[0] = (Val.UIntVal >> 24) & 255;
                             break;
     case Type::PointerTyID: if (getTargetData().getPointerSize() == 4)
                               goto Store4BytesBigEndian;
     case Type::DoubleTyID:
     case Type::ULongTyID:
     case Type::LongTyID:    Ptr->Untyped[7] =  Val.ULongVal        & 255;
                             Ptr->Untyped[6] = (Val.ULongVal >>  8) & 255;
                             Ptr->Untyped[5] = (Val.ULongVal >> 16) & 255;
                             Ptr->Untyped[4] = (Val.ULongVal >> 24) & 255;
                             Ptr->Untyped[3] = (Val.ULongVal >> 32) & 255;
                             Ptr->Untyped[2] = (Val.ULongVal >> 40) & 255;
                             Ptr->Untyped[1] = (Val.ULongVal >> 48) & 255;
                             Ptr->Untyped[0] = (Val.ULongVal >> 56) & 255;
                             break;
     default:
       std::cout << "Cannot store value of type " << Ty << "!\n";
     }
   }
 }

 /// FIXME: document
 ///
 GenericValue ExecutionEngine::LoadValueFromMemory(GenericValue *Ptr,
                                                   const Type *Ty) {
   GenericValue Result;
   if (getTargetData().isLittleEndian()) {
     switch (Ty->getPrimitiveID()) {
     case Type::BoolTyID:
     case Type::UByteTyID:
     case Type::SByteTyID:   Result.UByteVal = Ptr->Untyped[0]; break;
     case Type::UShortTyID:
     case Type::ShortTyID:   Result.UShortVal = (unsigned)Ptr->Untyped[0] |
                                               ((unsigned)Ptr->Untyped[1] << 8);
                             break;
     Load4BytesLittleEndian:
     case Type::FloatTyID:
     case Type::UIntTyID:
     case Type::IntTyID:     Result.UIntVal = (unsigned)Ptr->Untyped[0] |
                                             ((unsigned)Ptr->Untyped[1] <<  8) |
                                             ((unsigned)Ptr->Untyped[2] << 16) |
                                             ((unsigned)Ptr->Untyped[3] << 24);
                             break;
     case Type::PointerTyID: if (getTargetData().getPointerSize() == 4)
                               goto Load4BytesLittleEndian;
     case Type::DoubleTyID:
     case Type::ULongTyID:
     case Type::LongTyID:    Result.ULongVal = (uint64_t)Ptr->Untyped[0] |
                                              ((uint64_t)Ptr->Untyped[1] <<  8) |
                                              ((uint64_t)Ptr->Untyped[2] << 16) |
                                              ((uint64_t)Ptr->Untyped[3] << 24) |
                                              ((uint64_t)Ptr->Untyped[4] << 32) |
                                              ((uint64_t)Ptr->Untyped[5] << 40) |
                                              ((uint64_t)Ptr->Untyped[6] << 48) |
                                              ((uint64_t)Ptr->Untyped[7] << 56);
                             break;
     default:
       std::cout << "Cannot load value of type " << *Ty << "!\n";
       abort();
     }
   } else {
     switch (Ty->getPrimitiveID()) {
     case Type::BoolTyID:
     case Type::UByteTyID:
     case Type::SByteTyID:   Result.UByteVal = Ptr->Untyped[0]; break;
     case Type::UShortTyID:
     case Type::ShortTyID:   Result.UShortVal = (unsigned)Ptr->Untyped[1] |
                                               ((unsigned)Ptr->Untyped[0] << 8);
                             break;
     Load4BytesBigEndian:
     case Type::FloatTyID:
     case Type::UIntTyID:
     case Type::IntTyID:     Result.UIntVal = (unsigned)Ptr->Untyped[3] |
                                             ((unsigned)Ptr->Untyped[2] <<  8) |
                                             ((unsigned)Ptr->Untyped[1] << 16) |
                                             ((unsigned)Ptr->Untyped[0] << 24);
                             break;
     case Type::PointerTyID: if (getTargetData().getPointerSize() == 4)
                               goto Load4BytesBigEndian;
     case Type::DoubleTyID:
     case Type::ULongTyID:
     case Type::LongTyID:    Result.ULongVal = (uint64_t)Ptr->Untyped[7] |
                                              ((uint64_t)Ptr->Untyped[6] <<  8) |
                                              ((uint64_t)Ptr->Untyped[5] << 16) |
                                              ((uint64_t)Ptr->Untyped[4] << 24) |
                                              ((uint64_t)Ptr->Untyped[3] << 32) |
                                              ((uint64_t)Ptr->Untyped[2] << 40) |
                                              ((uint64_t)Ptr->Untyped[1] << 48) |
                                              ((uint64_t)Ptr->Untyped[0] << 56);
                             break;
     default:
       std::cout << "Cannot load value of type " << *Ty << "!\n";
       abort();
     }
   }
   return Result;
 }

 // InitializeMemory - Recursive function to apply a Constant value into the
 // specified memory location...
 //
 void ExecutionEngine::InitializeMemory(const Constant *Init, void *Addr) {
   if (Init->getType()->isFirstClassType()) {
     GenericValue Val = getConstantValue(Init);
     StoreValueToMemory(Val, (GenericValue*)Addr, Init->getType());
     return;
   }

   switch (Init->getType()->getPrimitiveID()) {
   case Type::ArrayTyID: {
     const ConstantArray *CPA = cast<ConstantArray>(Init);
     const std::vector<Use> &Val = CPA->getValues();
     unsigned ElementSize =
       getTargetData().getTypeSize(cast<ArrayType>(CPA->getType())->getElementType());
     for (unsigned i = 0; i < Val.size(); ++i)
       InitializeMemory(cast<Constant>(Val[i].get()), (char*)Addr+i*ElementSize);
     return;
   }

   case Type::StructTyID: {
     const ConstantStruct *CPS = cast<ConstantStruct>(Init);
     const StructLayout *SL =
       getTargetData().getStructLayout(cast<StructType>(CPS->getType()));
     const std::vector<Use> &Val = CPS->getValues();
     for (unsigned i = 0; i < Val.size(); ++i)
       InitializeMemory(cast<Constant>(Val[i].get()),
                        (char*)Addr+SL->MemberOffsets[i]);
     return;
   }

   default:
     std::cerr << "Bad Type: " << Init->getType() << "\n";
     assert(0 && "Unknown constant type to initialize memory with!");
   }
 }

 /// EmitGlobals - Emit all of the global variables to memory, storing their
 /// addresses into GlobalAddress.  This must make sure to copy the contents of
 /// their initializers into the memory.
 ///
 void ExecutionEngine::emitGlobals() {
   const TargetData &TD = getTargetData();

   // Loop over all of the global variables in the program, allocating the memory
   // to hold them.
   for (Module::giterator I = getModule().gbegin(), E = getModule().gend();
        I != E; ++I)
     if (!I->isExternal()) {
       // Get the type of the global...
       const Type *Ty = I->getType()->getElementType();

       // Allocate some memory for it!
       unsigned Size = TD.getTypeSize(Ty);
       GlobalAddress[I] = new char[Size];
       NumInitBytes += Size;

       DEBUG(std::cerr << "Global '" << I->getName() << "' -> "
                       << (void*)GlobalAddress[I] << "\n");
     } else {
       // External variable reference. Try to use the dynamic loader to
       // get a pointer to it.
       if (void *SymAddr = GetAddressOfSymbol(I->getName().c_str()))
         GlobalAddress[I] = SymAddr;
       else {
         std::cerr << "Could not resolve external global address: "
                   << I->getName() << "\n";
         abort();
       }
     }

   // Now that all of the globals are set up in memory, loop through them all and
   // initialize their contents.
   for (Module::giterator I = getModule().gbegin(), E = getModule().gend();
        I != E; ++I)
     if (!I->isExternal())
       InitializeMemory(I->getInitializer(), GlobalAddress[I]);
 }
	//===-- ExecutionEngine.cpp - Common Implementation shared by EEs ---------===//
	//
	// 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 defines the common interface used by the various execution engine
	// subclasses.
	//
	//===----------------------------------------------------------------------===//

	#define DEBUG_TYPE "jit"
	#include "Interpreter/Interpreter.h"
	#include "JIT/JIT.h"
	#include "llvm/Constants.h"
	#include "llvm/DerivedTypes.h"
	#include "llvm/Module.h"
	#include "llvm/ModuleProvider.h"
	#include "llvm/ExecutionEngine/ExecutionEngine.h"
	#include "llvm/ExecutionEngine/GenericValue.h"
	#include "llvm/Target/TargetData.h"
	#include "Support/Debug.h"
	#include "Support/Statistic.h"
	#include "Support/DynamicLinker.h"
	#include "Config/dlfcn.h"
	using namespace llvm;

	namespace {
	Statistic<> NumInitBytes("lli", "Number of bytes of global vars initialized");
	}

	ExecutionEngine::ExecutionEngine(ModuleProvider *P) :
	CurMod(*P->getModule()), MP(P) {
	assert(P && "ModuleProvider is null?");
	}

	ExecutionEngine::ExecutionEngine(Module M) : CurMod(M), MP(0) {
	assert(M && "Module is null?");
	}

	ExecutionEngine::~ExecutionEngine() {
	delete MP;
	}

	/// If possible, create a JIT, unless the caller specifically requests an
	/// Interpreter or there's an error. If even an Interpreter cannot be created,
	/// NULL is returned.
	///
	ExecutionEngine ExecutionEngine::create(ModuleProvider MP,
	bool ForceInterpreter) {
	ExecutionEngine *EE = 0;

	// Unless the interpreter was explicitly selected, make a JIT.
	if (!ForceInterpreter)
	EE = JIT::create(MP);

	// If we can't make a JIT, make an interpreter instead.
	try {
	if (EE == 0)
	EE = Interpreter::create(MP->materializeModule());
	} catch (...) {
	EE = 0;
	}
	return EE;
	}

	/// getPointerToGlobal - This returns the address of the specified global
	/// value. This may involve code generation if it's a function.
	///
	void ExecutionEngine::getPointerToGlobal(const GlobalValue GV) {
	if (Function F = const_cast<Function>(dyn_cast<Function>(GV)))
	return getPointerToFunction(F);

	assert(GlobalAddress[GV] && "Global hasn't had an address allocated yet?");
	return GlobalAddress[GV];
	}

	/// FIXME: document
	///
	GenericValue ExecutionEngine::getConstantValue(const Constant *C) {
	GenericValue Result;

	if (ConstantExpr CE = const_cast<ConstantExpr>(dyn_cast<ConstantExpr>(C))) {
	switch (CE->getOpcode()) {
	case Instruction::GetElementPtr: {
	Result = getConstantValue(CE->getOperand(0));
	std::vector<Value*> Indexes(CE->op_begin()+1, CE->op_end());
	uint64_t Offset =
	TD->getIndexedOffset(CE->getOperand(0)->getType(), Indexes);

	Result.LongVal += Offset;
	return Result;
	}
	case Instruction::Cast: {
	// We only need to handle a few cases here. Almost all casts will
	// automatically fold, just the ones involving pointers won't.
	//
	Constant *Op = CE->getOperand(0);

	// Handle cast of pointer to pointer...
	if (Op->getType()->getPrimitiveID() == C->getType()->getPrimitiveID())
	return getConstantValue(Op);

	// Handle a cast of pointer to any integral type...
	if (isa<PointerType>(Op->getType()) && C->getType()->isIntegral())
	return getConstantValue(Op);

	// Handle cast of long to pointer...
	if (isa<PointerType>(C->getType()) && (Op->getType() == Type::LongTy \|\|
	Op->getType() == Type::ULongTy))
	return getConstantValue(Op);
	break;
	}

	case Instruction::Add:
	if (CE->getOperand(0)->getType() == Type::LongTy \|\|
	CE->getOperand(0)->getType() == Type::ULongTy)
	Result.LongVal = getConstantValue(CE->getOperand(0)).LongVal +
	getConstantValue(CE->getOperand(1)).LongVal;
	else
	break;
	return Result;

	default:
	break;
	}
	std::cerr << "ConstantExpr not handled as global var init: " << *CE << "\n";
	abort();
	}

	switch (C->getType()->getPrimitiveID()) {
	#define GET_CONST_VAL(TY, CLASS) \
	case Type::TY##TyID: Result.TY##Val = cast<CLASS>(C)->getValue(); break
	GET_CONST_VAL(Bool , ConstantBool);
	GET_CONST_VAL(UByte , ConstantUInt);
	GET_CONST_VAL(SByte , ConstantSInt);
	GET_CONST_VAL(UShort , ConstantUInt);
	GET_CONST_VAL(Short , ConstantSInt);
	GET_CONST_VAL(UInt , ConstantUInt);
	GET_CONST_VAL(Int , ConstantSInt);
	GET_CONST_VAL(ULong , ConstantUInt);
	GET_CONST_VAL(Long , ConstantSInt);
	GET_CONST_VAL(Float , ConstantFP);
	GET_CONST_VAL(Double , ConstantFP);
	#undef GET_CONST_VAL
	case Type::PointerTyID:
	if (isa<ConstantPointerNull>(C)) {
	Result.PointerVal = 0;
	} else if (const ConstantPointerRef *CPR = dyn_cast<ConstantPointerRef>(C)){
	if (Function *F =
	const_cast<Function*>(dyn_cast<Function>(CPR->getValue())))
	Result = PTOGV(getPointerToFunctionOrStub(F));
	else
	Result = PTOGV(getPointerToGlobal(CPR->getValue()));

	} else {
	assert(0 && "Unknown constant pointer type!");
	}
	break;
	default:
	std::cout << "ERROR: Constant unimp for type: " << C->getType() << "\n";
	abort();
	}
	return Result;
	}

	/// FIXME: document
	///
	void ExecutionEngine::StoreValueToMemory(GenericValue Val, GenericValue *Ptr,
	const Type *Ty) {
	if (getTargetData().isLittleEndian()) {
	switch (Ty->getPrimitiveID()) {
	case Type::BoolTyID:
	case Type::UByteTyID:
	case Type::SByteTyID: Ptr->Untyped[0] = Val.UByteVal; break;
	case Type::UShortTyID:
	case Type::ShortTyID: Ptr->Untyped[0] = Val.UShortVal & 255;
	Ptr->Untyped[1] = (Val.UShortVal >> 8) & 255;
	break;
	Store4BytesLittleEndian:
	case Type::FloatTyID:
	case Type::UIntTyID:
	case Type::IntTyID: Ptr->Untyped[0] = Val.UIntVal & 255;
	Ptr->Untyped[1] = (Val.UIntVal >> 8) & 255;
	Ptr->Untyped[2] = (Val.UIntVal >> 16) & 255;
	Ptr->Untyped[3] = (Val.UIntVal >> 24) & 255;
	break;
	case Type::PointerTyID: if (getTargetData().getPointerSize() == 4)
	goto Store4BytesLittleEndian;
	case Type::DoubleTyID:
	case Type::ULongTyID:
	case Type::LongTyID: Ptr->Untyped[0] = Val.ULongVal & 255;
	Ptr->Untyped[1] = (Val.ULongVal >> 8) & 255;
	Ptr->Untyped[2] = (Val.ULongVal >> 16) & 255;
	Ptr->Untyped[3] = (Val.ULongVal >> 24) & 255;
	Ptr->Untyped[4] = (Val.ULongVal >> 32) & 255;
	Ptr->Untyped[5] = (Val.ULongVal >> 40) & 255;
	Ptr->Untyped[6] = (Val.ULongVal >> 48) & 255;
	Ptr->Untyped[7] = (Val.ULongVal >> 56) & 255;
	break;
	default:
	std::cout << "Cannot store value of type " << Ty << "!\n";
	}
	} else {
	switch (Ty->getPrimitiveID()) {
	case Type::BoolTyID:
	case Type::UByteTyID:
	case Type::SByteTyID: Ptr->Untyped[0] = Val.UByteVal; break;
	case Type::UShortTyID:
	case Type::ShortTyID: Ptr->Untyped[1] = Val.UShortVal & 255;
	Ptr->Untyped[0] = (Val.UShortVal >> 8) & 255;
	break;
	Store4BytesBigEndian:
	case Type::FloatTyID:
	case Type::UIntTyID:
	case Type::IntTyID: Ptr->Untyped[3] = Val.UIntVal & 255;
	Ptr->Untyped[2] = (Val.UIntVal >> 8) & 255;
	Ptr->Untyped[1] = (Val.UIntVal >> 16) & 255;
	Ptr->Untyped[0] = (Val.UIntVal >> 24) & 255;
	break;
	case Type::PointerTyID: if (getTargetData().getPointerSize() == 4)
	goto Store4BytesBigEndian;
	case Type::DoubleTyID:
	case Type::ULongTyID:
	case Type::LongTyID: Ptr->Untyped[7] = Val.ULongVal & 255;
	Ptr->Untyped[6] = (Val.ULongVal >> 8) & 255;
	Ptr->Untyped[5] = (Val.ULongVal >> 16) & 255;
	Ptr->Untyped[4] = (Val.ULongVal >> 24) & 255;
	Ptr->Untyped[3] = (Val.ULongVal >> 32) & 255;
	Ptr->Untyped[2] = (Val.ULongVal >> 40) & 255;
	Ptr->Untyped[1] = (Val.ULongVal >> 48) & 255;
	Ptr->Untyped[0] = (Val.ULongVal >> 56) & 255;
	break;
	default:
	std::cout << "Cannot store value of type " << Ty << "!\n";
	}
	}
	}

	/// FIXME: document
	///
	GenericValue ExecutionEngine::LoadValueFromMemory(GenericValue *Ptr,
	const Type *Ty) {
	GenericValue Result;
	if (getTargetData().isLittleEndian()) {
	switch (Ty->getPrimitiveID()) {
	case Type::BoolTyID:
	case Type::UByteTyID:
	case Type::SByteTyID: Result.UByteVal = Ptr->Untyped[0]; break;
	case Type::UShortTyID:
	case Type::ShortTyID: Result.UShortVal = (unsigned)Ptr->Untyped[0] \|
	((unsigned)Ptr->Untyped[1] << 8);
	break;
	Load4BytesLittleEndian:
	case Type::FloatTyID:
	case Type::UIntTyID:
	case Type::IntTyID: Result.UIntVal = (unsigned)Ptr->Untyped[0] \|
	((unsigned)Ptr->Untyped[1] << 8) \|
	((unsigned)Ptr->Untyped[2] << 16) \|
	((unsigned)Ptr->Untyped[3] << 24);
	break;
	case Type::PointerTyID: if (getTargetData().getPointerSize() == 4)
	goto Load4BytesLittleEndian;
	case Type::DoubleTyID:
	case Type::ULongTyID:
	case Type::LongTyID: Result.ULongVal = (uint64_t)Ptr->Untyped[0] \|
	((uint64_t)Ptr->Untyped[1] << 8) \|
	((uint64_t)Ptr->Untyped[2] << 16) \|
	((uint64_t)Ptr->Untyped[3] << 24) \|
	((uint64_t)Ptr->Untyped[4] << 32) \|
	((uint64_t)Ptr->Untyped[5] << 40) \|
	((uint64_t)Ptr->Untyped[6] << 48) \|
	((uint64_t)Ptr->Untyped[7] << 56);
	break;
	default:
	std::cout << "Cannot load value of type " << *Ty << "!\n";
	abort();
	}
	} else {
	switch (Ty->getPrimitiveID()) {
	case Type::BoolTyID:
	case Type::UByteTyID:
	case Type::SByteTyID: Result.UByteVal = Ptr->Untyped[0]; break;
	case Type::UShortTyID:
	case Type::ShortTyID: Result.UShortVal = (unsigned)Ptr->Untyped[1] \|
	((unsigned)Ptr->Untyped[0] << 8);
	break;
	Load4BytesBigEndian:
	case Type::FloatTyID:
	case Type::UIntTyID:
	case Type::IntTyID: Result.UIntVal = (unsigned)Ptr->Untyped[3] \|
	((unsigned)Ptr->Untyped[2] << 8) \|
	((unsigned)Ptr->Untyped[1] << 16) \|
	((unsigned)Ptr->Untyped[0] << 24);
	break;
	case Type::PointerTyID: if (getTargetData().getPointerSize() == 4)
	goto Load4BytesBigEndian;
	case Type::DoubleTyID:
	case Type::ULongTyID:
	case Type::LongTyID: Result.ULongVal = (uint64_t)Ptr->Untyped[7] \|
	((uint64_t)Ptr->Untyped[6] << 8) \|
	((uint64_t)Ptr->Untyped[5] << 16) \|
	((uint64_t)Ptr->Untyped[4] << 24) \|
	((uint64_t)Ptr->Untyped[3] << 32) \|
	((uint64_t)Ptr->Untyped[2] << 40) \|
	((uint64_t)Ptr->Untyped[1] << 48) \|
	((uint64_t)Ptr->Untyped[0] << 56);
	break;
	default:
	std::cout << "Cannot load value of type " << *Ty << "!\n";
	abort();
	}
	}
	return Result;
	}

	// InitializeMemory - Recursive function to apply a Constant value into the
	// specified memory location...
	//
	void ExecutionEngine::InitializeMemory(const Constant Init, void Addr) {
	if (Init->getType()->isFirstClassType()) {
	GenericValue Val = getConstantValue(Init);
	StoreValueToMemory(Val, (GenericValue*)Addr, Init->getType());
	return;
	}

	switch (Init->getType()->getPrimitiveID()) {
	case Type::ArrayTyID: {
	const ConstantArray *CPA = cast<ConstantArray>(Init);
	const std::vector<Use> &Val = CPA->getValues();
	unsigned ElementSize =
	getTargetData().getTypeSize(cast<ArrayType>(CPA->getType())->getElementType());
	for (unsigned i = 0; i < Val.size(); ++i)
	InitializeMemory(cast<Constant>(Val[i].get()), (char)Addr+iElementSize);
	return;
	}

	case Type::StructTyID: {
	const ConstantStruct *CPS = cast<ConstantStruct>(Init);
	const StructLayout *SL =
	getTargetData().getStructLayout(cast<StructType>(CPS->getType()));
	const std::vector<Use> &Val = CPS->getValues();
	for (unsigned i = 0; i < Val.size(); ++i)
	InitializeMemory(cast<Constant>(Val[i].get()),
	(char*)Addr+SL->MemberOffsets[i]);
	return;
	}

	default:
	std::cerr << "Bad Type: " << Init->getType() << "\n";
	assert(0 && "Unknown constant type to initialize memory with!");
	}
	}

	/// EmitGlobals - Emit all of the global variables to memory, storing their
	/// addresses into GlobalAddress. This must make sure to copy the contents of
	/// their initializers into the memory.
	///
	void ExecutionEngine::emitGlobals() {
	const TargetData &TD = getTargetData();

	// Loop over all of the global variables in the program, allocating the memory
	// to hold them.
	for (Module::giterator I = getModule().gbegin(), E = getModule().gend();
	I != E; ++I)
	if (!I->isExternal()) {
	// Get the type of the global...
	const Type *Ty = I->getType()->getElementType();

	// Allocate some memory for it!
	unsigned Size = TD.getTypeSize(Ty);
	GlobalAddress[I] = new char[Size];
	NumInitBytes += Size;

	DEBUG(std::cerr << "Global '" << I->getName() << "' -> "
	<< (void*)GlobalAddress[I] << "\n");
	} else {
	// External variable reference. Try to use the dynamic loader to
	// get a pointer to it.
	if (void *SymAddr = GetAddressOfSymbol(I->getName().c_str()))
	GlobalAddress[I] = SymAddr;
	else {
	std::cerr << "Could not resolve external global address: "
	<< I->getName() << "\n";
	abort();
	}
	}

	// Now that all of the globals are set up in memory, loop through them all and
	// initialize their contents.
	for (Module::giterator I = getModule().gbegin(), E = getModule().gend();
	I != E; ++I)
	if (!I->isExternal())
	InitializeMemory(I->getInitializer(), GlobalAddress[I]);
	}