/*
 *  JIT compile ClamAV bytecode.
 *
 *  Copyright (C) 2015 Cisco Systems, Inc. and/or its affiliates. All rights reserved.
 *  Copyright (C) 2009-2010 Sourcefire, Inc.
 *
 *  Authors: Török Edvin
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License version 2 as
 *  published by the Free Software Foundation.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
 *  MA 02110-1301, USA.
 */
#define DEBUG_TYPE "clamavjit"
#include <pthread.h>
#ifndef _WIN32
#include <sys/time.h>
#endif
#include <cstdlib>
#include <csetjmp>
#include <new>
#include <cerrno>
#include <string>

#include "ClamBCModule.h"
#include "ClamBCDiagnostics.h"
#include "llvm30_compat.h"

#include "llvm/ADT/DenseMap.h"
#include "llvm/ADT/BitVector.h"
#include "llvm/ADT/PostOrderIterator.h"
#include "llvm/ADT/StringMap.h"
#include "llvm/ADT/StringSwitch.h"
#include "llvm/ADT/Triple.h"
#include "llvm/ADT/SmallSet.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/Analysis/LoopInfo.h"
#include "llvm/Analysis/ScalarEvolution.h"
#if LLVM_VERSION < 35
#include "llvm/Analysis/Verifier.h"
#include "llvm/AutoUpgrade.h"
#include "llvm/Support/TargetFolder.h"
#else
#include "llvm/IR/Verifier.h"
#include "llvm/IR/AutoUpgrade.h"
#include "llvm/Analysis/TargetFolder.h"
#endif
#include "llvm/ExecutionEngine/ExecutionEngine.h"
#if LLVM_VERSION < 36
#include "llvm/ExecutionEngine/JIT.h"
#else
#include "llvm/ExecutionEngine/MCJIT.h"
#include "llvm/Support/DynamicLibrary.h"
#include "llvm/Object/ObjectFile.h"
#endif
#include "llvm/ExecutionEngine/JITEventListener.h"
#include "llvm/PassManager.h"
#include "llvm/Support/Compiler.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/ManagedStatic.h"
#include "llvm/Support/MemoryBuffer.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Support/SourceMgr.h"
#include "llvm/Support/PrettyStackTrace.h"

#if LLVM_VERSION < 29
#include "llvm/System/DataTypes.h"
#include "llvm/System/Host.h"
#include "llvm/System/Memory.h"
#include "llvm/System/Mutex.h"
#include "llvm/System/Signals.h"
#include "llvm/System/Threading.h"
#include "llvm/System/ThreadLocal.h"
#else
#include "llvm/PassRegistry.h"
#include "llvm/Support/DataTypes.h"
#include "llvm/Support/FileSystem.h"
#include "llvm/Support/Host.h"
#include "llvm/Support/Memory.h"
#include "llvm/Support/Mutex.h"
#include "llvm/Support/Signals.h"
#include "llvm/Support/Threading.h"
#include "llvm/Support/ThreadLocal.h"
#endif

#if LLVM_VERSION < 33
#include "llvm/IntrinsicInst.h"
#else
#include "llvm/IR/IntrinsicInst.h"
#endif

#include "llvm/Support/Timer.h"

extern "C" {
void LLVMInitializeX86AsmPrinter();
void LLVMInitializePowerPCAsmPrinter();
}

#if LLVM_VERSION < 30
#include "llvm/Target/TargetSelect.h"
#else
#include "llvm/Support/TargetSelect.h"
#endif

#include "llvm/Target/TargetOptions.h"
#include "llvm/Transforms/Scalar.h"
#include "llvm/Transforms/IPO.h"
#include "llvm/Transforms/Utils/BasicBlockUtils.h"

#if LLVM_VERSION < 32
#include "llvm/Analysis/DebugInfo.h"
#elif LLVM_VERSION < 35
#include "llvm/DebugInfo.h"
#else
#include "llvm/IR/DebugInfo.h"
#endif

#if LLVM_VERSION < 32
#include "llvm/Support/IRBuilder.h"
#include "llvm/Target/TargetData.h"
#elif LLVM_VERSION < 33
#include "llvm/IRBuilder.h"
#include "llvm/DataLayout.h"
#else
#include "llvm/IR/IRBuilder.h"
#include "llvm/IR/DataLayout.h"
#endif

#if LLVM_VERSION < 33
#include "llvm/CallingConv.h"
#include "llvm/DerivedTypes.h"
#include "llvm/Function.h"
#include "llvm/LLVMContext.h"
#include "llvm/Intrinsics.h"
#include "llvm/Module.h"
#else
#include "llvm/IR/CallingConv.h"
#include "llvm/IR/DerivedTypes.h"
#include "llvm/IR/Function.h"
#include "llvm/IR/LLVMContext.h"
#include "llvm/IR/Intrinsics.h"
#include "llvm/IR/Module.h"
#endif

#if LLVM_VERSION < 34
#include "llvm/Support/CFG.h"
#else
#include "llvm/Analysis/CFG.h"
#endif

#if LLVM_VERSION >= 35
#include "llvm/IR/Dominators.h"
#endif

//#define TIMING
#undef TIMING

#include "llvm/Config/config.h"
#ifdef ENABLE_THREADS
#if !ENABLE_THREADS
#error "Thread support was explicitly disabled. Cannot continue"
#endif
#endif

#ifdef LLVM_ENABLE_THREADS
#if !LLVM_ENABLE_THREADS
#error "Thread support was explicitly disabled. Cannot continue"
#endif
#endif

#ifdef _GLIBCXX_PARALLEL
#error "libstdc++ parallel mode is not supported for ClamAV. Please remove -D_GLIBCXX_PARALLEL from CXXFLAGS!"
#endif

#ifdef HAVE_CONFIG_H
#undef PACKAGE_BUGREPORT
#undef PACKAGE_NAME
#undef PACKAGE_STRING
#undef PACKAGE_TARNAME
#undef PACKAGE_VERSION
#undef PACKAGE_URL
#include "clamav-config.h"
#endif

#include <openssl/ssl.h>
#include <openssl/err.h>

#include "dconf.h"
#include "clamav.h"
#include "clambc.h"
#include "bytecode.h"
#include "bytecode_priv.h"
#include "type_desc.h"

#define MODULE "libclamav JIT: "

extern "C" unsigned int cli_rndnum(unsigned int max);
using namespace llvm;
typedef DenseMap<const struct cli_bc_func*, void*> FunctionMapTy;
struct cli_bcengine {
    ExecutionEngine *EE;
    JITEventListener *Listener;
    LLVMContext Context;
    FunctionMapTy compiledFunctions;
    union {
	unsigned char b[16];
	void* align;/* just to align field to ptr */
    } guard;
};

extern "C" uint8_t cli_debug_flag;
#if LLVM_VERSION >= 29
namespace llvm {
    void initializeRuntimeLimitsPass(PassRegistry&);
};
#endif
namespace {

#if LLVM_VERSION >= 28
#define llvm_report_error(x) report_fatal_error(x)
#define llvm_install_error_handler(x) install_fatal_error_handler(x)
#define DwarfExceptionHandling JITExceptionHandling
#define SetCurrentDebugLocation(x) SetCurrentDebugLocation(DebugLoc::getFromDILocation(x))
#define DEFINEPASS(passname) passname() : FunctionPass(ID)
#else
#define DEFINEPASS(passname) passname() : FunctionPass(&ID)
#endif

#if LLVM_VERSION >= 29
#define NORETURN LLVM_ATTRIBUTE_NORETURN
#endif

static sys::ThreadLocal<const jmp_buf> ExceptionReturn;

static void UpgradeCall(CallInst *&C, Function *Intr)
{
    Function *New;
    if (!UpgradeIntrinsicFunction(Intr, New) || New == Intr)
	return;
    UpgradeIntrinsicCall(C, New);
}

extern "C" {
#ifdef __GNUC__
void cli_errmsg(const char *str, ...) __attribute__((format(printf, 1, 2)));
#else
void cli_errmsg(const char *str, ...);
#endif

#ifdef __GNUC__
void cli_warnmsg(const char *str, ...) __attribute__((format(printf, 1, 2)));
#else
void cli_warnmsg(const char *str, ...);
#endif

#ifdef __GNUC__
void cli_dbgmsg_internal(const char *str, ...) __attribute__((format(printf, 1, 2)));
#else
void cli_dbgmsg_internal(const char *str, ...);
#endif
}

class ScopedExceptionHandler {
    public:
	jmp_buf &getEnv() { return env;}
	void Set() {
	    /* set the exception handler's return location to here for the
	     * current thread */
	    ExceptionReturn.set((const jmp_buf*)&env);
	}
	~ScopedExceptionHandler() {
	    /* leaving scope, remove exception handler for current thread */
	    ExceptionReturn.erase();
	}
    private:
	jmp_buf env;
};
#define HANDLER_TRY(handler) \
    if (setjmp(handler.getEnv()) == 0) {\
	handler.Set();

#define HANDLER_END(handler) \
    } else cli_warnmsg("[Bytecode JIT]: recovered from error\n");


void do_shutdown() {
    ScopedExceptionHandler handler;
    HANDLER_TRY(handler) {
	// TODO: be on the safe side, and clear errors here,
	// otherwise destructor calls report_fatal_error
	((class raw_fd_ostream&)errs()).clear_error();

	llvm_shutdown();

	((class raw_fd_ostream&)errs()).clear_error();
    }
    HANDLER_END(handler);
    remove_fatal_error_handler();
}

static void NORETURN jit_exception_handler(void)
{
    jmp_buf* buf = const_cast<jmp_buf*>(ExceptionReturn.get());
    if (buf) {
	// For errors raised during bytecode generation and execution.
	longjmp(*buf, 1);
    } else {
	// Oops, got no error recovery pointer set up,
	// this is probably an error raised during shutdown.
	cli_errmsg("[Bytecode JIT]: exception handler called, but no recovery point set up");
	// should never happen, we remove the error handler when we don't use
	// LLVM anymore, and when we use it, we do set an error recovery point.
	llvm_unreachable("Bytecode JIT]: no exception handler recovery installed, but exception hit!");
    }
}

static void NORETURN jit_ssp_handler(void)
{
    cli_errmsg("[Bytecode JIT]: *** stack smashing detected, bytecode aborted\n");
    jit_exception_handler();
}

#if LLVM_VERSION < 33
void llvm_error_handler(void *user_data, const std::string &reason)
#else
void llvm_error_handler(void *user_data, const std::string &reason, bool gen_crash_diag = true)
#endif
{
    // Output it to stderr, it might exceed the 1k/4k limit of cli_errmsg
    cli_errmsg("[Bytecode JIT]: [LLVM error] %s\n", reason.c_str());
    jit_exception_handler();
}

// Since libgcc is not available on all compilers (for example on win32),
// just define what these functions should do, the compiler will forward to
// the appropriate libcall if needed.
static int64_t rtlib_sdiv_i64(int64_t a, int64_t b)
{
    return a/b;
}

static uint64_t rtlib_udiv_i64(uint64_t a, uint64_t b)
{
    return a/b;
}

static int64_t rtlib_srem_i64(int64_t a, int64_t b)
{
    return a%b;
}

static uint64_t rtlib_urem_i64(uint64_t a, uint64_t b)
{
    return a%b;
}

static int64_t rtlib_mul_i64(uint64_t a, uint64_t b)
{
    return a*b;
}

static int64_t rtlib_shl_i64(int64_t a, int32_t b)
{
    return a << b;
}

static int64_t rtlib_srl_i64(int64_t a, int32_t b)
{
    return (uint64_t)a >> b;
}
/* Implementation independent sign-extended signed right shift */
#ifdef HAVE_SAR
#define CLI_SRS(n,s) ((n)>>(s))
#else
#define CLI_SRS(n,s) ((((n)>>(s)) ^ (1<<(sizeof(n)*8-1-s))) - (1<<(sizeof(n)*8-1-s)))
#endif
static int64_t rtlib_sra_i64(int64_t a, int32_t b)
{
    return CLI_SRS(a, b);//CLI_./..
}

static void rtlib_bzero(void *s, size_t n)
{
    memset(s, 0, n);
}

#ifdef _WIN32
#ifdef _WIN64
extern "C" void __chkstk(void);
#else
extern "C" void _chkstk(void);
#endif
#endif
#ifdef __CYGWIN__
extern "C" void _alloca(void);
#endif
// Resolve integer libcalls, but nothing else.
static void* noUnknownFunctions(const std::string& name) {
    void *addr =
	StringSwitch<void*>(name)
	.Case("__divdi3", (void*)(intptr_t)rtlib_sdiv_i64)
	.Case("__udivdi3", (void*)(intptr_t)rtlib_udiv_i64)
	.Case("__moddi3", (void*)(intptr_t)rtlib_srem_i64)
	.Case("__umoddi3", (void*)(intptr_t)rtlib_urem_i64)
	.Case("__muldi3", (void*)(intptr_t)rtlib_mul_i64)
	.Case("__ashrdi3", (void*)(intptr_t)rtlib_sra_i64)
	.Case("__ashldi3", (void*)(intptr_t)rtlib_shl_i64)
	.Case("__lshrdi3", (void*)(intptr_t)rtlib_srl_i64)
	.Case("__bzero", (void*)(intptr_t)rtlib_bzero)
	.Case("memmove", (void*)(intptr_t)memmove)
	.Case("memcpy", (void*)(intptr_t)memcpy)
	.Case("memset", (void*)(intptr_t)memset)
	.Case("abort", (void*)(intptr_t)jit_exception_handler)
#ifdef _WIN32
#ifdef _WIN64
	.Case("_chkstk", (void*)(intptr_t)__chkstk)
#else
	.Case("_chkstk", (void*)(intptr_t)_chkstk)
#endif
#endif
#ifdef __CYGWIN__
	.Case("_alloca", (void*)(intptr_t)_alloca)
#endif
	.Default(0);
    if (addr)
	return addr;

#if LLVM_VERSION < 36
    std::string reason((Twine("Attempt to call external function ")+name).str());
    llvm_error_handler(0, reason);
#else
    // noUnknownFunctions relies on addGlobalMapping, which doesn't work with MCJIT.
    // Now the function pointers are found with SymbolSearching.
#endif
    return 0;
}

class NotifyListener : public JITEventListener {
public:
#if LLVM_VERSION < 36
    virtual void NotifyFunctionEmitted(const Function &F,
				       void *Code, size_t Size,
				       const EmittedFunctionDetails &Details)
    {
	if (!cli_debug_flag)
	    return;
	cli_dbgmsg_internal("[Bytecode JIT]: emitted function %s of %ld bytes at %p\n",
#if LLVM_VERSION < 31
			    F.getNameStr().c_str(), (long)Size, Code);
#else
			    F.getName().str().c_str(), (long)Size, Code);
#endif
    }
#else
    // MCJIT doesn't emit single functions, but instead whole objects.
    virtual void NotifyObjectEmitted(const object::ObjectFile &Obj,
                                     const RuntimeDyld::LoadedObjectInfo &L)
    {
        if (!cli_debug_flag)
            return;
        cli_dbgmsg_internal("[Bytecode JIT]; emitted %s %s of %zd bytes\n",
                            Obj.getFileFormatName().str().c_str(),
                            Obj.getFileName().str().c_str(), Obj.getData().size());
    }
#endif
};

class TimerWrapper {
private:
    Timer *t;
public:
    TimerWrapper(const std::string &name) {
	t = 0;
#ifdef TIMING
	t = new Timer(name);
#endif
    }
    ~TimerWrapper()
    {
	if (t)
	    delete t;
    }
    void startTimer()
    {
	if (t)
	    t->startTimer();
    }
    void stopTimer()
    {
	if (t)
	    t->stopTimer();
    }
};

class LLVMTypeMapper {
private:
#if LLVM_VERSION < 30
    std::vector<PATypeHolder> TypeMap;
#else
    std::vector<Type*> TypeMap;
#endif
    LLVMContext &Context;
    unsigned numTypes;
    constType *getStatic(uint16_t ty)
    {
	if (!ty)
	    return Type::getVoidTy(Context);
	if (ty <= 64)
	    return IntegerType::get(Context, ty);
	switch (ty) {
	    case 65:
		return PointerType::getUnqual(Type::getInt8Ty(Context));
	    case 66:
		return PointerType::getUnqual(Type::getInt16Ty(Context));
	    case 67:
		return PointerType::getUnqual(Type::getInt32Ty(Context));
	    case 68:
		return PointerType::getUnqual(Type::getInt64Ty(Context));
	}
	llvm_unreachable("getStatic");
    }
public:
    TimerWrapper pmTimer;
    TimerWrapper irgenTimer;

    LLVMTypeMapper(LLVMContext &Context, const struct cli_bc_type *types,
		   unsigned count, constType *Hidden=0) : Context(Context), numTypes(count),
    pmTimer("Function passes"),irgenTimer("IR generation")
    {
	TypeMap.reserve(count);
	// During recursive type construction pointers to Type* may be
	// invalidated, so we must use a TypeHolder to an Opaque type as a
	// start.
	for (unsigned i=0;i<count;i++) {
#if LLVM_VERSION < 30
	    TypeMap.push_back(OpaqueType::get(Context));
#else
	    TypeMap.push_back(0);
#endif
	}
	for (unsigned i=0;i<count;i++) {
	    const struct cli_bc_type *type = &types[i];

	    constType *Ty = buildType(type, types, Hidden, 0);
#if LLVM_VERSION < 30
	    // Make the opaque type a concrete type, doing recursive type
	    // unification if needed.
	    cast<OpaqueType>(TypeMap[i].get())->refineAbstractTypeTo(Ty);
#else
	    TypeMap[i] = Ty;
#endif
	}
    }

    constType *buildType(const struct cli_bc_type *type, const struct cli_bc_type *types, constType *Hidden,
			 int recursive)
    {
	std::vector<constType*> Elts;
	unsigned n = type->kind == DArrayType ? 1 : type->numElements;
	for (unsigned j=0;j<n;j++) {
	    Elts.push_back(get(type->containedTypes[j], types, Hidden));
	}
	constType *Ty;
	switch (type->kind) {
	    case DFunctionType:
		{
		    assert(Elts.size() > 0 && "Function with no return type?");
		    constType *RetTy = Elts[0];
		    if (Hidden)
			Elts[0] = Hidden;
		    else
			Elts.erase(Elts.begin());
		    Ty = FunctionType::get(RetTy, Elts, false);
		    break;
		}
	    case DPointerType:
		if (!PointerType::isValidElementType(Elts[0]))
		    Ty = PointerType::getUnqual(Type::getInt8Ty(Context));
		else
		    Ty = PointerType::getUnqual(Elts[0]);
		break;
	    case DStructType:
	    case DPackedStructType:
		Ty = StructType::get(Context, Elts, type->kind == DPackedStructType);
		break;
	    case DArrayType:
		Ty = ArrayType::get(Elts[0], type->numElements);
		break;
	    default:
		llvm_unreachable("type->kind");
	}
	return Ty;
    }

    constType *get(uint16_t ty, const struct cli_bc_type *types, constType *Hidden)
    {
	ty &= 0x7fff;
	if (ty < 69)
	    return getStatic(ty);
	ty -= 69;
	assert(ty < numTypes && "TypeID out of range");
#if LLVM_VERSION < 30
	return TypeMap[ty].get();
#else
	Type *Ty = TypeMap[ty];
	if (Ty)
	    return Ty;
	assert(types && Hidden || "accessing not-yet-built type");
	Ty = buildType(&types[ty], types, Hidden, 1);
	TypeMap[ty] = Ty;
	return Ty;
#endif
    }
};

struct CommonFunctions {
    Function *FHandler;
    Function *FMemset;
    Function *FMemmove;
    Function *FMemcpy;
    Function *FRealmemset;
    Function *FRealMemmove;
    Function *FRealmemcmp;
    Function *FRealmemcpy;
    Function *FBSwap16;
    Function *FBSwap32;
    Function *FBSwap64;
};

// loops with tripcounts higher than this need timeout check
static const unsigned LoopThreshold = 1000;

// after every N API calls we need timeout check
static const unsigned ApiThreshold = 100;

class RuntimeLimits : public FunctionPass {
    typedef SmallVector<std::pair<const BasicBlock*, const BasicBlock*>, 16>
	BBPairVectorTy;
    typedef SmallSet<BasicBlock*, 16> BBSetTy;
    typedef DenseMap<const BasicBlock*, unsigned> BBMapTy;
    bool loopNeedsTimeoutCheck(ScalarEvolution &SE, const Loop *L, BBMapTy &Map) {
	// This BB is a loop header, if trip count is small enough
	// no timeout checks are needed here.
	const SCEV *S = SE.getMaxBackedgeTakenCount(L);
	if (isa<SCEVCouldNotCompute>(S))
	    return true;
	DEBUG(errs() << "Found loop trip count" << *S << "\n");
	ConstantRange CR = SE.getUnsignedRange(S);
	uint64_t max = CR.getUnsignedMax().getLimitedValue();
	DEBUG(errs() << "Found max trip count " << max << "\n");
	if (max > LoopThreshold)
	    return true;
	unsigned apicalls = 0;
	for (Loop::block_iterator J=L->block_begin(),JE=L->block_end();
	     J != JE; ++J) {
	    apicalls += Map[*J];
	}
	apicalls *= max;
	if (apicalls > ApiThreshold) {
	    DEBUG(errs() << "apicall threshold exceeded: " << apicalls << "\n");
	    return true;
	}
	Map[L->getHeader()] = apicalls;
	return false;
    }

public:
    static char ID;
    DEFINEPASS(RuntimeLimits) {
#if LLVM_VERSION >= 29
	PassRegistry &Registry = *PassRegistry::getPassRegistry();
	initializeRuntimeLimitsPass(Registry);
#endif
    }

    virtual bool runOnFunction(Function &F) {
	BBSetTy BackedgeTargets;
	if (!F.isDeclaration()) {
	    // Get the common backedge targets.
	    // Note that we don't rely on LoopInfo here, since
	    // it is possible to construct a CFG that doesn't have natural loops,
	    // yet it does have backedges, and thus can lead to unbounded/high
	    // execution time.
	    BBPairVectorTy V;
	    FindFunctionBackedges(F, V);
	    for (BBPairVectorTy::iterator I=V.begin(),E=V.end();I != E; ++I) {
		BackedgeTargets.insert(const_cast<BasicBlock*>(I->second));
	    }
	}
	BBSetTy  needsTimeoutCheck;
	BBMapTy BBMap;
#if LLVM_VERSION < 35
	DominatorTree &DT = getAnalysis<DominatorTree>();
#else
	DominatorTree &DT = getAnalysis<DominatorTreeWrapperPass>().getDomTree();
#endif
	for (Function::iterator I=F.begin(),E=F.end(); I != E; ++I) {
	    BasicBlock *BB = &*I;
	    unsigned apicalls = 0;
	    for (BasicBlock::const_iterator J=BB->begin(),JE=BB->end();
		 J != JE; ++J) {
		if (const CallInst *CI = dyn_cast<CallInst>(J)) {
		    Function *F = CI->getCalledFunction();
		    if (!F || F->isDeclaration())
			apicalls++;
		}
	    }
	    if (apicalls > ApiThreshold) {
		DEBUG(errs() << "apicall threshold exceeded: " << apicalls << "\n");
		needsTimeoutCheck.insert(BB);
		apicalls = 0;
	    }
	    BBMap[BB] = apicalls;
	}
	if (!BackedgeTargets.empty()) {
	    LoopInfo &LI = getAnalysis<LoopInfo>();
	    ScalarEvolution &SE = getAnalysis<ScalarEvolution>();

	    // Now check whether any of these backedge targets are part of a loop
	    // with a small constant trip count
	    for (BBSetTy::iterator I=BackedgeTargets.begin(),E=BackedgeTargets.end();
		 I != E; ++I) {
		const Loop *L = LI.getLoopFor(*I);
		if (L && L->getHeader() == *I &&
		    !loopNeedsTimeoutCheck(SE, L, BBMap))
		    continue;
		needsTimeoutCheck.insert(*I);
		BBMap[*I] = 0;
	    }
	}
	// Estimate number of apicalls by walking dominator-tree bottom-up.
	// BBs that have timeout checks are considered to have 0 APIcalls
	// (since we already checked for timeout).
	for (po_iterator<DomTreeNode*> I = po_begin(DT.getRootNode()),
	     E = po_end(DT.getRootNode()); I != E; ++I) {
	    if (needsTimeoutCheck.count(I->getBlock()))
		continue;
	    unsigned apicalls = BBMap[I->getBlock()];
	    for (DomTreeNode::iterator J=I->begin(),JE=I->end();
		 J != JE; ++J) {
		apicalls += BBMap[(*J)->getBlock()];
	    }
	    if (apicalls > ApiThreshold) {
		needsTimeoutCheck.insert(I->getBlock());
		apicalls = 0;
	    }
	    BBMap[I->getBlock()] = apicalls;
	}
	if (needsTimeoutCheck.empty())
	    return false;
	DEBUG(errs() << "needs timeoutcheck:\n");
	std::vector<constType*>args;
	FunctionType* abrtTy = FunctionType::get(
	    Type::getVoidTy(F.getContext()),args,false);
	Constant *func_abort =
	    F.getParent()->getOrInsertFunction("abort", abrtTy);
	BasicBlock *AbrtBB = BasicBlock::Create(F.getContext(), "", &F);
        CallInst* AbrtC = CallInst::Create(func_abort, "", AbrtBB);
        AbrtC->setCallingConv(CallingConv::C);
        AbrtC->setTailCall(true);
#if LLVM_VERSION < 32
        AbrtC->setDoesNotReturn(true);
        AbrtC->setDoesNotThrow(true);
#else
        AbrtC->setDoesNotReturn();
        AbrtC->setDoesNotThrow();
#endif
        new UnreachableInst(F.getContext(), AbrtBB);
	IRBuilder<false> Builder(F.getContext());

	Value *Flag = F.arg_begin();
#if LLVM_VERSION < 30
	Function *LSBarrier = Intrinsic::getDeclaration(F.getParent(),
							Intrinsic::memory_barrier);
	Value *MBArgs[] = {
	    ConstantInt::getFalse(F.getContext()),
	    ConstantInt::getFalse(F.getContext()),
	    ConstantInt::getTrue(F.getContext()),
	    ConstantInt::getFalse(F.getContext()),
	    ConstantInt::getFalse(F.getContext())
	};
#endif
	verifyFunction(F);
	BasicBlock *BB = &F.getEntryBlock();
	Builder.SetInsertPoint(BB, BB->getTerminator());
	Flag = Builder.CreatePointerCast(Flag, PointerType::getUnqual(
		Type::getInt1Ty(F.getContext())));
	for (BBSetTy::iterator I=needsTimeoutCheck.begin(),
	     E=needsTimeoutCheck.end(); I != E; ++I) {
	    BasicBlock *BB = *I;
	    Builder.SetInsertPoint(BB, BB->getTerminator());
#if LLVM_VERSION < 30
	    // store-load barrier: will be a no-op on x86 but not other arches
	    Builder.CreateCall(LSBarrier, ARRAYREF(Value*, MBArgs, MBArgs+5));
#else
	    Builder.CreateFence(Release);
#endif
	    // Load Flag that tells us we timed out (first byte in bc_ctx)
	    Value *Cond = Builder.CreateLoad(Flag, true);
	    BasicBlock *newBB = SplitBlock(BB, BB->getTerminator(), this);
	    TerminatorInst *TI = BB->getTerminator();
	    BranchInst::Create(AbrtBB, newBB, Cond, TI);
	    TI->eraseFromParent();
	    // Update dominator info
	    DomTreeNode *N = DT.getNode(AbrtBB);
	    if (!N) {
		DT.addNewBlock(AbrtBB, BB);
	    } else {
		BasicBlock *DomBB = DT.findNearestCommonDominator(BB,
								  N->getIDom()->getBlock());
		DT.changeImmediateDominator(AbrtBB, DomBB);
	    }
	    DEBUG(errs() << *I << "\n");
	}
	//verifyFunction(F);
	return true;
    }

    virtual void getAnalysisUsage(AnalysisUsage &AU) const {
      AU.setPreservesAll();
      AU.addRequired<LoopInfo>();
      AU.addRequired<ScalarEvolution>();
#if LLVM_VERSION < 35
      AU.addRequired<DominatorTree>();
#else
      AU.addRequired<DominatorTreeWrapperPass>();
#endif
    }
};
char RuntimeLimits::ID;

// select i1 false ... which instcombine would simplify but we don't run
// instcombine.
class BrSimplifier : public FunctionPass {
public:
    static char ID;
    DEFINEPASS(BrSimplifier) {}

    virtual bool runOnFunction(Function &F) {
	bool Changed = false;
	for (Function::iterator I=F.begin(),E=F.end(); I != E; ++I) {
	    if (BranchInst *BI = dyn_cast<BranchInst>(I->getTerminator())) {
		if (BI->isUnconditional())
		    continue;
		Value *V = BI->getCondition();
		if (ConstantInt *CI = dyn_cast<ConstantInt>(V)) {
		    BasicBlock *Other;
		    if (CI->isOne()) {
			BranchInst::Create(BI->getSuccessor(0), &*I);
			Other = BI->getSuccessor(1);
		    } else {
			BranchInst::Create(BI->getSuccessor(1), &*I);
			Other = BI->getSuccessor(0);
		    }
		    Other->removePredecessor(&*I);
		    BI->eraseFromParent();
		    Changed = true;
		}
	    }
	    for (BasicBlock::iterator J=I->begin(),JE=I->end();
		 J != JE;) {
		SelectInst *SI = dyn_cast<SelectInst>(J);
		++J;
		if (!SI)
		    continue;
		ConstantInt *CI = dyn_cast<ConstantInt>(SI->getCondition());
		if (!CI)
		    continue;
		if (CI->isOne())
		    SI->replaceAllUsesWith(SI->getTrueValue());
		else
		    SI->replaceAllUsesWith(SI->getFalseValue());
		SI->eraseFromParent();
		Changed = true;
	    }
	}

	return Changed;
    }
};
char BrSimplifier::ID;
/*
class SimpleGlobalDCE : public ModulePass {
    ExecutionEngine *EE;
public:
    static char ID;
    SimpleGlobalDCE(ExecutionEngine *EE) : ModulePass(&ID), EE(EE) {}

    virtual bool runOnModule(Module &M) {
	bool Changed = false;
	std::vector<GlobalValue*> toErase;
	for (Module::global_iterator I = M.global_begin(), E = M.global_end(); I != E; ++I) {
	    GlobalValue *GV = &*I;
	    if (GV->use_empty() && !EE->getPointerToGlobalIfAvailable(GV))
		toErase.push_back(GV);
	}
	for (std::vector<GlobalValue*>::iterator I=toErase.begin(), E=toErase.end();
	     I != E; ++I) {
	    (*I)->eraseFromParent();
	    Changed = true;
	}

	return Changed;
    }
};
char SimpleGlobalDCE::ID;
*/
class LLVMCodegen {
private:
    const struct cli_bc *bc;
    Module *M;
    LLVMContext &Context;
    ExecutionEngine *EE;
    FunctionPassManager &PM, &PMUnsigned;
    LLVMTypeMapper *TypeMap;

    Function **apiFuncs;
    LLVMTypeMapper &apiMap;
    FunctionMapTy &compiledFunctions;
    Twine BytecodeID;

    TargetFolder Folder;
    IRBuilder<false, TargetFolder> Builder;

    std::vector<Value*> globals;
    DenseMap<unsigned, unsigned> GVoffsetMap;
    DenseMap<unsigned, constType*> GVtypeMap;
    Value **Values;
    unsigned numLocals;
    unsigned numArgs;
    std::vector<MDNode*> mdnodes;

    struct CommonFunctions *CF;

    Value *getOperand(const struct cli_bc_func *func, constType *Ty, operand_t operand)
    {
	unsigned map[] = {0, 1, 2, 3, 3, 4, 4, 4, 4};
	if (operand < func->numValues)
	    return Values[operand];
	unsigned w = Ty->getPrimitiveSizeInBits();
	if (w > 1)
	    w = (w+7)/8;
	else
	    w = 0;
	return convertOperand(func, map[w], operand);
    }

    Value *convertOperand(const struct cli_bc_func *func, constType *Ty, operand_t operand)
    {
	unsigned map[] = {0, 1, 2, 3, 3, 4, 4, 4, 4};
	if (operand < func->numArgs)
	    return Values[operand];
	if (operand < func->numValues) {
	    Value *V = Values[operand];
	    if (func->types[operand]&0x8000 && V->getType() == Ty) {
		return V;
	    }
	    V = Builder.CreateLoad(V);
	    if (V->getType() != Ty &&
		isa<PointerType>(V->getType()) &&
		isa<PointerType>(Ty))
		V = Builder.CreateBitCast(V, Ty);
	    if (V->getType() != Ty) {
		if (cli_debug_flag) {
		    std::string str;
		    raw_string_ostream ostr(str);
		    ostr << operand << " " ;
		    V->print(ostr);
		    Ty->print(ostr);
		    M->dump();
		    cli_dbgmsg_internal("[Bytecode JIT]: operand %d: %s\n", operand,ostr.str().c_str());
		}
		llvm_report_error("(libclamav) Type mismatch converting operand");
	    }
	    return V;
	}
	unsigned w = Ty->getPrimitiveSizeInBits();
	if (w > 1)
	    w = (w+7)/8;
	else
	    w = 0;
	return convertOperand(func, map[w], operand);
    }

    Value *convertOperand(const struct cli_bc_func *func,
			  const struct cli_bc_inst *inst,  operand_t operand)
    {
	return convertOperand(func, inst->interp_op%5, operand);
    }

    Value *convertOperand(const struct cli_bc_func *func,
			  unsigned w, operand_t operand) {
	if (operand < func->numArgs)
	    return Values[operand];
	if (operand < func->numValues) {
	    if (func->types[operand]&0x8000)
		return Values[operand];
	    return Builder.CreateLoad(Values[operand]);
	}

	if (operand & 0x80000000) {
	    operand &= 0x7fffffff;
	    assert(operand < globals.size() && "Global index out of range");
	    // Global
	    if (!operand)
		return ConstantPointerNull::get(PointerType::getUnqual(Type::getInt8Ty(Context)));
	    assert(globals[operand]);
	    if (GlobalVariable *GV = dyn_cast<GlobalVariable>(globals[operand])) {
		if (ConstantExpr *CE = dyn_cast<ConstantExpr>(GV->getInitializer())) {
		    return CE;
		}
		return GV;
	    }
	    return globals[operand];
	}
	// Constant
	operand -= func->numValues;
	// This was already validated by libclamav.
	assert(operand < func->numConstants && "Constant out of range");
	uint64_t *c = &func->constants[operand];
	uint64_t v;
	constType *Ty;
	switch (w) {
	    case 0:
	    case 1:
		Ty = w ? Type::getInt8Ty(Context) :
		    Type::getInt1Ty(Context);
		v = *(uint8_t*)c;
		break;
	    case 2:
		Ty = Type::getInt16Ty(Context);
		v = *(uint16_t*)c;
		break;
	    case 3:
		Ty = Type::getInt32Ty(Context);
		v = *(uint32_t*)c;
		break;
	    case 4:
		Ty = Type::getInt64Ty(Context);
		v = *(uint64_t*)c;
		break;
	    default:
		llvm_unreachable("width");
	}
	return ConstantInt::get(Ty, v);
    }

    void Store(uint16_t dest, Value *V)
    {
	assert(dest >= numArgs && dest < numLocals+numArgs && "Instruction destination out of range");
	Builder.CreateStore(V, Values[dest]);
    }

    // Insert code that calls \arg CF->FHandler if \arg FailCond is true.
    void InsertVerify(Value *FailCond, BasicBlock *&Fail, Function *FHandler, 
		      Function *F) {
	if (!Fail) {
	    Fail = BasicBlock::Create(Context, "fail", F);
	    CallInst::Create(FHandler,"",Fail);
	    new UnreachableInst(Context, Fail);
	}
	BasicBlock *OkBB = BasicBlock::Create(Context, "", F);
	Builder.CreateCondBr(FailCond, Fail, OkBB);
	Builder.SetInsertPoint(OkBB);
    }

    constType* mapType(uint16_t typeID)
    {
	return TypeMap->get(typeID&0x7fffffff, NULL, NULL);
    }

    Constant *buildConstant(constType *Ty, uint64_t *components, unsigned &c)
    {
        if (constPointerType *PTy = dyn_cast<PointerType>(Ty)) {
          Value *idxs[1] = {
	      ConstantInt::get(Type::getInt64Ty(Context), components[c++])
	  };
	  unsigned idx = components[c++];
	  if (!idx)
	      return ConstantPointerNull::get(PTy);
	  assert(idx < globals.size());
	  GlobalVariable *GV = cast<GlobalVariable>(globals[idx]);
	  Type *IP8Ty = PointerType::getUnqual(Type::getInt8Ty(Ty->getContext()));
	  Constant *C = ConstantExpr::getPointerCast(GV, IP8Ty);
	  //TODO: check constant bounds here
	  return ConstantExpr::getPointerCast(
	      ConstantExpr::getInBoundsGetElementPtr(C, ARRAYREF(Value*, idxs, 1)),
	      PTy);
        }
	if (isa<IntegerType>(Ty)) {
	    return ConstantInt::get(Ty, components[c++]);
	}
	if (constArrayType *ATy = dyn_cast<ArrayType>(Ty)) {
	   std::vector<Constant*> elements;
	   elements.reserve(ATy->getNumElements());
	   for (unsigned i=0;i<ATy->getNumElements();i++) {
	       elements.push_back(buildConstant(ATy->getElementType(), components, c));
	   }
	   return ConstantArray::get(ATy, elements);
	}
	if (constStructType *STy = dyn_cast<StructType>(Ty)) {
	   std::vector<Constant*> elements;
	   elements.reserve(STy->getNumElements());
	   for (unsigned i=0;i<STy->getNumElements();i++) {
	       elements.push_back(buildConstant(STy->getElementType(i), components, c));
	   }
	   return ConstantStruct::get(STy, elements);
	}
	Ty->dump();
	llvm_unreachable("invalid type");
	return 0;
    }

public:
    LLVMCodegen(const struct cli_bc *bc, Module *M, struct CommonFunctions *CF, FunctionMapTy &cFuncs,
		ExecutionEngine *EE, FunctionPassManager &PM, FunctionPassManager &PMUnsigned,
		Function **apiFuncs, LLVMTypeMapper &apiMap)
	: bc(bc), M(M), Context(M->getContext()), EE(EE),
	PM(PM),PMUnsigned(PMUnsigned), TypeMap(), apiFuncs(apiFuncs),apiMap(apiMap),
	compiledFunctions(cFuncs), BytecodeID("bc"+Twine(bc->id)),
#if LLVM_VERSION < 32
	Folder(EE->getTargetData()), Builder(Context, Folder), Values(), CF(CF) {
#else
	Folder(EE->getDataLayout()), Builder(Context, Folder), Values(), CF(CF) {
#endif

	for (unsigned i=0;i<cli_apicall_maxglobal - _FIRST_GLOBAL;i++) {
	    unsigned id = cli_globals[i].globalid;
	    GVoffsetMap[id] = cli_globals[i].offset;
	}
	numLocals = 0;
	numArgs = 0;
    }

#if LLVM_VERSION < 30
    template <typename InputIterator>
#endif
    Value* createGEP(Value *Base, constType *ETy, ARRAYREFPARAM(Value*,InputIterator Start,InputIterator End,ARef)) {
	constType *Ty = GetElementPtrInst::getIndexedType(Base->getType(),ARRAYREFP(Start,End,ARef));
	if (!Ty || (ETy && (Ty != ETy && (!isa<IntegerType>(Ty) || !isa<IntegerType>(ETy))))) {
	    if (cli_debug_flag) {
		std::string str;
		raw_string_ostream ostr(str);

		ostr << "Wrong indices for GEP opcode: "
		    << " expected type: " << *ETy;
		if (Ty)
		    ostr << " actual type: " << *Ty;
		ostr << " base: " << *Base << ";";
		Base->getType()->print(ostr);
		ostr << "\n indices: ";
#if LLVM_VERSION < 30
		for (InputIterator I=Start; I != End; I++) {
#else
		for (ArrayRef<Value*>::iterator I=ARef.begin(); I != ARef.end(); I++) {
#endif
		    ostr << **I << ", ";
		}
		ostr << "\n";
		cli_dbgmsg_internal("[Bytecode JIT]: %s\n", ostr.str().c_str());
	    } else {
		cli_warnmsg("[Bytecode JIT]: Wrong indices for GEP opcode\n");
	    }
	    return 0;
	}
	return Builder.CreateGEP(Base,ARRAYREFP(Start,End,ARef));
    }

#if LLVM_VERSION < 30
    template <typename InputIterator>
#endif
    bool createGEP(unsigned dest, Value *Base, ARRAYREFPARAM(Value*,InputIterator Start,InputIterator End,ARef)) {
	assert(dest >= numArgs && dest < numLocals+numArgs && "Instruction destination out of range");
	constType *ETy = cast<PointerType>(cast<PointerType>(Values[dest]->getType())->getElementType())->getElementType();
	Value *V = createGEP(Base, ETy, ARRAYREFP(Start,End,ARef));
	if (!V) {
	    if (cli_debug_flag)
		cli_dbgmsg_internal("[Bytecode JIT] @%d\n", dest);
	    return false;
	}
	V = Builder.CreateBitCast(V, PointerType::getUnqual(ETy));
	Store(dest, V);
	return true;
    }

    MDNode *convertMDNode(unsigned i) {
	if (i < mdnodes.size()) {
	    if (mdnodes[i])
		return mdnodes[i];
	} else 
	    mdnodes.resize(i+1);
	assert(i < mdnodes.size());
	const struct cli_bc_dbgnode *node = &bc->dbgnodes[i];
#if LLVM_VERSION < 36
	Value **Vals = new Value*[node->numelements];
#else
	Metadata **Vals = new Metadata*[node->numelements];
#endif
	for (unsigned j=0;j<node->numelements;j++) {
	    const struct cli_bc_dbgnode_element* el = &node->elements[j];
#if LLVM_VERSION < 36
	    Value *V;
#else
	    Metadata *V;
#endif
	    if (!el->len) {
		if (el->nodeid == ~0u)
		    V = 0;
		else if (el->nodeid)
		    V = convertMDNode(el->nodeid);
		else
		    V = MDString::get(Context, "");
	    } else if (el->string) {
		V = MDString::get(Context, StringRef(el->string, el->len));
	    } else {
#if LLVM_VERSION < 36
		V = ConstantInt::get(IntegerType::get(Context, el->len),
				     el->constant);
#else
		V = ConstantAsMetadata::get(ConstantInt::get(IntegerType::get(Context, el->len),
				     el->constant));
#endif
	    }
	    Vals[j] = V;
	}
#if LLVM_VERSION < 36
	MDNode *N = MDNode::get(Context, ARRAYREF(Value*,Vals, node->numelements));
#else
	MDNode *N = MDNode::get(Context, ARRAYREF(Metadata*,Vals, node->numelements));
#endif
	delete[] Vals;
	mdnodes[i] = N;
	return N;
    }

    void AddStackProtect(Function *F)
    {
	BasicBlock &BB = F->getEntryBlock();
	if (isa<AllocaInst>(BB.begin())) {
	    // Have an alloca -> some instruction uses its address otherwise
	    // mem2reg would have converted it to an SSA register.
	    // Enable stack protector for this function.
#if LLVM_VERSION < 29
	    // LLVM 2.9 has broken SSP, it does a 'mov 0x28, $rax', which tries
	    // to read from the address 0x28 and crashes
	    F->addFnAttr(Attribute::StackProtectReq);
#endif
	}
	// always add stackprotect attribute (bb #2239), so we know this
	// function was verified. If there is no alloca it won't actually add
	// stack protector in emitted code so this won't slow down the app.
#if LLVM_VERSION < 29
	F->addFnAttr(Attribute::StackProtect);
#endif
    }

    Value *GEPOperand(Value *V) {
	if (LoadInst *LI = dyn_cast<LoadInst>(V)) {
	    Value *VI = LI->getOperand(0);
	    StoreInst *SI = 0;
	    for (Value::use_iterator I=VI->use_begin(),
		 E=VI->use_end(); I != E; ++I) {
		Value *I_V = *I;
		if (StoreInst *S = dyn_cast<StoreInst>(I_V)) {
		    if (SI)
			return V;
		    SI = S;
		} else if (!isa<LoadInst>(I_V))
		    return V;
	    }
	    V = SI->getOperand(0);
	}
#if LLVM_VERSION < 32
	if (EE->getTargetData()->getPointerSize() == 8) {
#else
	if (EE->getDataLayout()->getPointerSize() == 8) {
#endif
	    // eliminate useless trunc, GEP can take i64 too
	    if (TruncInst *I = dyn_cast<TruncInst>(V)) {
		Value *Src = I->getOperand(0);
		if (Src->getType() == Type::getInt64Ty(Context) &&
		    I->getType() == Type::getInt32Ty(Context))
		    return Src;
	    }
	}
	return V;
    }

   Function* generate() {
        PrettyStackTraceString CrashInfo("Generate LLVM IR functions");
	apiMap.irgenTimer.startTimer();
	TypeMap = new LLVMTypeMapper(Context, bc->types + 4, bc->num_types - 5);
	for (unsigned i=0;i<bc->dbgnode_cnt;i++) {
	    mdnodes.push_back(convertMDNode(i));
	}

	for (unsigned i=0;i<cli_apicall_maxglobal - _FIRST_GLOBAL;i++) {
	    unsigned id = cli_globals[i].globalid;
	    constType *Ty = apiMap.get(cli_globals[i].type, NULL, NULL);
	    /*if (const ArrayType *ATy = dyn_cast<ArrayType>(Ty))
		Ty = PointerType::getUnqual(ATy->getElementType());*/
	    GVtypeMap[id] = Ty;
	}

	// The hidden ctx param to all functions
	unsigned maxh = cli_globals[0].offset + sizeof(struct cli_bc_hooks);
	constType *HiddenCtx = PointerType::getUnqual(ArrayType::get(Type::getInt8Ty(Context), maxh));

	globals.reserve(bc->num_globals);
	BitVector FakeGVs;
	FakeGVs.resize(bc->num_globals);
	globals.push_back(0);
	for (unsigned i=1;i<bc->num_globals;i++) {
	    constType *Ty = mapType(bc->globaltys[i]);

	    // TODO: validate number of components against type_components
	    unsigned c = 0;
	    GlobalVariable *GV;
	    if (isa<PointerType>(Ty)) {
		unsigned g = bc->globals[i][1];
		if (GVoffsetMap.count(g)) {
		    FakeGVs.set(i);
		    globals.push_back(0);
		    continue;
		}
	    }
	    Constant *C = buildConstant(Ty, bc->globals[i], c);
	    GV = new GlobalVariable(*M, Ty, true,
				    GlobalValue::InternalLinkage,
				    C, "glob"+Twine(i));
	    globals.push_back(GV);
	}
	Function **Functions = new Function*[bc->num_func];
	for (unsigned j=0;j<bc->num_func;j++) {
	    // Create LLVM IR Function
	    const struct cli_bc_func *func = &bc->funcs[j];
	    std::vector<constType*> argTypes;
	    argTypes.push_back(HiddenCtx);
	    for (unsigned a=0;a<func->numArgs;a++) {
		argTypes.push_back(mapType(func->types[a]));
	    }
	    constType *RetTy = mapType(func->returnType);
	    FunctionType *FTy =  FunctionType::get(RetTy, argTypes,
							 false);
	    Functions[j] = Function::Create(FTy, Function::InternalLinkage,
					   BytecodeID+"f"+Twine(j), M);
	    Functions[j]->setDoesNotThrow();
	    Functions[j]->setCallingConv(CallingConv::Fast);
	    Functions[j]->setLinkage(GlobalValue::InternalLinkage);
#ifdef C_LINUX
	    /* bb #2270, this should really be fixed either by LLVM or GCC.*/
#if LLVM_VERSION < 32
	    Functions[j]->addFnAttr(Attribute::constructStackAlignmentFromInt(16));
#else
	// TODO: How does this translate?
//	    Functions[j]->addFnAttr(Attribute::StackAlignment);
#endif
#endif
	}
	constType *I32Ty = Type::getInt32Ty(Context);
	for (unsigned j=0;j<bc->num_func;j++) {
	    PrettyStackTraceString CrashInfo("Generate LLVM IR");
	    const struct cli_bc_func *func = &bc->funcs[j];
	    bool broken = false;

	    // Create all BasicBlocks
	    Function *F = Functions[j];
	    BasicBlock **BB = new BasicBlock*[func->numBB];
	    for (unsigned i=0;i<func->numBB;i++) {
		BB[i] = BasicBlock::Create(Context, "", F);
	    }

	    BasicBlock *Fail = 0;
	    Values = new Value*[func->numValues];
	    Builder.SetInsertPoint(BB[0]);
	    Function::arg_iterator I = F->arg_begin();
	    assert(F->arg_size() == (unsigned)(func->numArgs + 1) && "Mismatched args");
	    ++I;
	    for (unsigned i=0;i<func->numArgs; i++) {
		assert(I != F->arg_end());
		Values[i] = &*I;
		++I;
	    }
	    for (unsigned i=func->numArgs;i<func->numValues;i++) {
		if (!func->types[i]) {
		    //instructions without return value, like store
		    Values[i] = 0;
		    continue;
		}
		Values[i] = Builder.CreateAlloca(mapType(func->types[i]));
	    }
	    numLocals = func->numLocals;
	    numArgs = func->numArgs;

	    if (FakeGVs.any()) {
		Argument *Ctx = F->arg_begin();
		for (unsigned i=0;i<bc->num_globals;i++) {
		    if (!FakeGVs[i])
			continue;
		    unsigned g = bc->globals[i][1];
		    unsigned offset = GVoffsetMap[g];

		    Constant *Idx = ConstantInt::get(Type::getInt32Ty(Context),
						     offset);
		    Value *Idxs[2] = {
			ConstantInt::get(Type::getInt32Ty(Context), 0),
			Idx
		    };
		    Value *GEP = Builder.CreateInBoundsGEP(Ctx, ARRAYREF(Value*, Idxs, Idxs+2));
		    constType *Ty = GVtypeMap[g];
		    Ty = PointerType::getUnqual(PointerType::getUnqual(Ty));
		    Value *Cast = Builder.CreateBitCast(GEP, Ty);
		    Value *SpecialGV = Builder.CreateLoad(Cast);
		    constType *IP8Ty = Type::getInt8Ty(Context);
		    IP8Ty = PointerType::getUnqual(IP8Ty);
		    SpecialGV = Builder.CreateBitCast(SpecialGV, IP8Ty);
		    SpecialGV->setName("g"+Twine(g-_FIRST_GLOBAL)+"_");
		    Value *C[] = {
			ConstantInt::get(Type::getInt32Ty(Context), bc->globals[i][0])
		    };
		    globals[i] = createGEP(SpecialGV, 0, ARRAYREF(Value*,C, C+1));
		    if (!globals[i]) {
			if (cli_debug_flag) {
			    std::string str;
			    raw_string_ostream ostr(str);
			    ostr << i << ":" << g << ":" << bc->globals[i][0] <<"\n";
			    Ty->print(ostr);
			    cli_dbgmsg_internal("[Bytecode JIT]: %s\n", ostr.str().c_str());
			}
			llvm_report_error("(libclamav) unable to create fake global");
		    }
		    globals[i] = Builder.CreateBitCast(globals[i], Ty);
		    if(GetElementPtrInst *GI = dyn_cast<GetElementPtrInst>(globals[i])) {
			GI->setIsInBounds(true);
			GI->setName("geped"+Twine(i)+"_");
		    }
		}
	    }

	    // Generate LLVM IR for each BB
	    for (unsigned i=0;i<func->numBB && !broken;i++) {
		bool unreachable = false;
		const struct cli_bc_bb *bb = &func->BB[i];
		Builder.SetInsertPoint(BB[i]);
		unsigned c = 0;
		for (unsigned j=0;j<bb->numInsts && !broken;j++) {
		    const struct cli_bc_inst *inst = &bb->insts[j];
		    Value *Op0=0, *Op1=0, *Op2=0;
		    // libclamav has already validated this.
		    assert(inst->opcode < OP_BC_INVALID && "Invalid opcode");
		    if (func->dbgnodes) {
			if (func->dbgnodes[c] != ~0u) {
			unsigned j = func->dbgnodes[c];
			assert(j < mdnodes.size());
			Builder.SetCurrentDebugLocation(mdnodes[j]);
			} else
			    Builder.SetCurrentDebugLocation(0);
		    }
		    c++;
		    switch (inst->opcode) {
			case OP_BC_JMP:
			case OP_BC_BRANCH:
			case OP_BC_CALL_API:
			case OP_BC_CALL_DIRECT:
			case OP_BC_ZEXT:
			case OP_BC_SEXT:
			case OP_BC_TRUNC:
			case OP_BC_GEP1:
			case OP_BC_GEPZ:
			case OP_BC_GEPN:
			case OP_BC_STORE:
			case OP_BC_COPY:
			case OP_BC_RET:
			case OP_BC_PTRDIFF32:
			case OP_BC_PTRTOINT64:
			    // these instructions represents operands differently
			    break;
			default:
			    switch (operand_counts[inst->opcode]) {
				case 1:
				    Op0 = convertOperand(func, inst, inst->u.unaryop);
				    break;
				case 2:
				    Op0 = convertOperand(func, inst, inst->u.binop[0]);
				    Op1 = convertOperand(func, inst, inst->u.binop[1]);
				    if (Op0->getType() != Op1->getType()) {
					Op0->dump();
					Op1->dump();
					llvm_report_error("(libclamav) binop type mismatch");
				    }
				    break;
				case 3:
				    Op0 = convertOperand(func, inst, inst->u.three[0]);
				    Op1 = convertOperand(func, inst, inst->u.three[1]);
				    Op2 = convertOperand(func, inst, inst->u.three[2]);
				    break;
			    }
		    }

		    switch (inst->opcode) {
			case OP_BC_ADD:
			    Store(inst->dest, Builder.CreateAdd(Op0, Op1));
			    break;
			case OP_BC_SUB:
			    Store(inst->dest, Builder.CreateSub(Op0, Op1));
			    break;
			case OP_BC_MUL:
			    Store(inst->dest, Builder.CreateMul(Op0, Op1));
			    break;
			case OP_BC_UDIV:
			{
			    Value *Bad = Builder.CreateICmpEQ(Op1, ConstantInt::get(Op1->getType(), 0));
			    InsertVerify(Bad, Fail, CF->FHandler, F);
			    Store(inst->dest, Builder.CreateUDiv(Op0, Op1));
			    break;
			}
			case OP_BC_SDIV:
			{
			    //TODO: also verify Op0 == -1 && Op1 = INT_MIN
			    Value *Bad = Builder.CreateICmpEQ(Op1, ConstantInt::get(Op1->getType(), 0));
			    InsertVerify(Bad, Fail, CF->FHandler, F);
			    Store(inst->dest, Builder.CreateSDiv(Op0, Op1));
			    break;
			}
			case OP_BC_UREM:
			{
			    Value *Bad = Builder.CreateICmpEQ(Op1, ConstantInt::get(Op1->getType(), 0));
			    InsertVerify(Bad, Fail, CF->FHandler, F);
			    Store(inst->dest, Builder.CreateURem(Op0, Op1));
			    break;
			}
			case OP_BC_SREM:
			{
			    //TODO: also verify Op0 == -1 && Op1 = INT_MIN
			    Value *Bad = Builder.CreateICmpEQ(Op1, ConstantInt::get(Op1->getType(), 0));
			    InsertVerify(Bad, Fail, CF->FHandler, F);
			    Store(inst->dest, Builder.CreateSRem(Op0, Op1));
			    break;
			}
			case OP_BC_SHL:
			    Store(inst->dest, Builder.CreateShl(Op0, Op1));
			    break;
			case OP_BC_LSHR:
			    Store(inst->dest, Builder.CreateLShr(Op0, Op1));
			    break;
			case OP_BC_ASHR:
			    Store(inst->dest, Builder.CreateAShr(Op0, Op1));
			    break;
			case OP_BC_AND:
			    Store(inst->dest, Builder.CreateAnd(Op0, Op1));
			    break;
			case OP_BC_OR:
			    Store(inst->dest, Builder.CreateOr(Op0, Op1));
			    break;
			case OP_BC_XOR:
			    Store(inst->dest, Builder.CreateXor(Op0, Op1));
			    break;
			case OP_BC_TRUNC:
			{
			    Value *Src = convertOperand(func, inst, inst->u.cast.source);
			    constType *Ty = mapType(func->types[inst->dest]);
			    Store(inst->dest, Builder.CreateTrunc(Src,  Ty));
			    break;
			}
			case OP_BC_ZEXT:
			{
			    Value *Src = convertOperand(func, inst, inst->u.cast.source);
			    constType *Ty = mapType(func->types[inst->dest]);
			    Store(inst->dest, Builder.CreateZExt(Src,  Ty));
			    break;
			}
			case OP_BC_SEXT:
			{
			    Value *Src = convertOperand(func, inst, inst->u.cast.source);
			    constType *Ty = mapType(func->types[inst->dest]);
			    Store(inst->dest, Builder.CreateSExt(Src,  Ty));
			    break;
			}
			case OP_BC_BRANCH:
			{
			    Value *Cond = convertOperand(func, inst, inst->u.branch.condition);
			    BasicBlock *True = BB[inst->u.branch.br_true];
			    BasicBlock *False = BB[inst->u.branch.br_false];
			    if (Cond->getType() != Type::getInt1Ty(Context)) {
				cli_warnmsg("[Bytecode JIT]: type mismatch in condition");
				broken = true;
				break;
			    }
			    Builder.CreateCondBr(Cond, True, False);
			    break;
			}
			case OP_BC_JMP:
			{
			    BasicBlock *Jmp = BB[inst->u.jump];
			    Builder.CreateBr(Jmp);
			    break;
			}
			case OP_BC_RET:
			{
			    Op0 = convertOperand(func, F->getReturnType(), inst->u.unaryop);
			    Builder.CreateRet(Op0);
			    break;
			}
			case OP_BC_RET_VOID:
			    Builder.CreateRetVoid();
			    break;
			case OP_BC_ICMP_EQ:
			    Store(inst->dest, Builder.CreateICmpEQ(Op0, Op1));
			    break;
			case OP_BC_ICMP_NE:
			    Store(inst->dest, Builder.CreateICmpNE(Op0, Op1));
			    break;
			case OP_BC_ICMP_UGT:
			    Store(inst->dest, Builder.CreateICmpUGT(Op0, Op1));
			    break;
			case OP_BC_ICMP_UGE:
			    Store(inst->dest, Builder.CreateICmpUGE(Op0, Op1));
			    break;
			case OP_BC_ICMP_ULT:
			    Store(inst->dest, Builder.CreateICmpULT(Op0, Op1));
			    break;
			case OP_BC_ICMP_ULE:
			    Store(inst->dest, Builder.CreateICmpULE(Op0, Op1));
			    break;
			case OP_BC_ICMP_SGT:
			    Store(inst->dest, Builder.CreateICmpSGT(Op0, Op1));
			    break;
			case OP_BC_ICMP_SGE:
			    Store(inst->dest, Builder.CreateICmpSGE(Op0, Op1));
			    break;
			case OP_BC_ICMP_SLT:
			    Store(inst->dest, Builder.CreateICmpSLT(Op0, Op1));
			    break;
			case OP_BC_ICMP_SLE:
			    Store(inst->dest, Builder.CreateICmpSLE(Op0, Op1));
			    break;
			case OP_BC_SELECT:
			    Store(inst->dest, Builder.CreateSelect(Op0, Op1, Op2));
			    break;
			case OP_BC_COPY:
			{
			    Value *Dest = Values[inst->u.binop[1]];
			    constPointerType *PTy = cast<PointerType>(Dest->getType());
			    Op0 = convertOperand(func, PTy->getElementType(), inst->u.binop[0]);
			    PTy = PointerType::getUnqual(Op0->getType());
			    Dest = Builder.CreateBitCast(Dest, PTy);
			    Builder.CreateStore(Op0, Dest);
			    break;
			}
			case OP_BC_CALL_DIRECT:
			{
			    Function *DestF = Functions[inst->u.ops.funcid];
			    SmallVector<Value*, 2> args;
			    args.push_back(&*F->arg_begin()); // pass hidden arg
			    for (unsigned a=0;a<inst->u.ops.numOps;a++) {
				operand_t op = inst->u.ops.ops[a];
				args.push_back(convertOperand(func, DestF->getFunctionType()->getParamType(a+1), op));
			    }
			    CallInst *CI = Builder.CreateCall(DestF, ARRAYREF(Value*, args.begin(), args.end()));
			    CI->setCallingConv(CallingConv::Fast);
#if LLVM_VERSION < 32
			    CI->setDoesNotThrow(true);
#else
			    CI->setDoesNotThrow();
#endif
			    if (CI->getType()->getTypeID() != Type::VoidTyID)
				Store(inst->dest, CI);
			    break;
			}
			case OP_BC_CALL_API:
			{
			    assert(inst->u.ops.funcid < cli_apicall_maxapi && "APICall out of range");
			    std::vector<Value*> args;
			    Function *DestF = apiFuncs[inst->u.ops.funcid];
			    if (!strcmp(cli_apicalls[inst->u.ops.funcid].name, "engine_functionality_level")) {
				Store(inst->dest,
				      ConstantInt::get(Type::getInt32Ty(Context),
						       cl_retflevel()));
			    } else {
			    args.push_back(&*F->arg_begin()); // pass hidden arg
			    for (unsigned a=0;a<inst->u.ops.numOps;a++) {
				operand_t op = inst->u.ops.ops[a];
				args.push_back(convertOperand(func, DestF->getFunctionType()->getParamType(a+1), op));
			    }
			    CallInst *CI = Builder.CreateCall(DestF, ARRAYREFVECTOR(Value*, args));
#if LLVM_VERSION < 32
			    CI->setDoesNotThrow(true);
#else
			    CI->setDoesNotThrow();
#endif
			    Store(inst->dest, CI);
			    }
			    break;
			}
			case OP_BC_GEP1:
			{
			    constType *SrcTy = mapType(inst->u.three[0]);
			    Value *V = convertOperand(func, SrcTy, inst->u.three[1]);
			    Value *Op = convertOperand(func, I32Ty, inst->u.three[2]);
			    Op = GEPOperand(Op);
			    if (!createGEP(inst->dest, V, ARRAYREF(Value*, &Op, &Op+1))) {
				cli_warnmsg("[Bytecode JIT]: OP_BC_GEP1 createGEP failed\n");
				broken = true;
			    }
			    break;
			}
			case OP_BC_GEPZ:
			{
			    Value *Ops[2];
			    Ops[0] = ConstantInt::get(Type::getInt32Ty(Context), 0);
			    constType *SrcTy = mapType(inst->u.three[0]);
			    Value *V = convertOperand(func, SrcTy, inst->u.three[1]);
			    Ops[1] = convertOperand(func, I32Ty, inst->u.three[2]);
			    Ops[1] = GEPOperand(Ops[1]);
			    if (!createGEP(inst->dest, V, ARRAYREF(Value*, Ops, Ops+2))) {
				cli_warnmsg("[Bytecode JIT]: OP_BC_GEPZ createGEP failed\n");
				broken = true;
			    }
			    break;
			}
			case OP_BC_GEPN:
			{
			    std::vector<Value*> Idxs;
			    assert(inst->u.ops.numOps > 2);
			    constType *SrcTy = mapType(inst->u.ops.ops[0]);
			    Value *V = convertOperand(func, SrcTy, inst->u.ops.ops[1]);
			    for (unsigned a=2;a<inst->u.ops.numOps;a++) {
				Value *Op = convertOperand(func, I32Ty, inst->u.ops.ops[a]);
				Op = GEPOperand(Op);
				Idxs.push_back(Op);
			    }
			    if (!createGEP(inst->dest, V, ARRAYREFVECTOR(Value*, Idxs))) {
				cli_warnmsg("[Bytecode JIT]: OP_BC_GEPN createGEP failed\n");
				broken = true;
			    }
			    break;
			}
			case OP_BC_STORE:
			{
			    Value *Dest = convertOperand(func, inst, inst->u.binop[1]);
			    Value *V = convertOperand(func, inst, inst->u.binop[0]);
			    constType *VPTy = PointerType::getUnqual(V->getType());
			    if (VPTy != Dest->getType())
				Dest = Builder.CreateBitCast(Dest, VPTy);
			    Builder.CreateStore(V, Dest);
			    break;
			}
			case OP_BC_LOAD:
			{
			    Op0 = Builder.CreateBitCast(Op0,
							Values[inst->dest]->getType());
			    Op0 = Builder.CreateLoad(Op0);
			    Store(inst->dest, Op0);
			    break;
			}
			case OP_BC_MEMSET:
			{
			    Value *Dst = convertOperand(func, inst, inst->u.three[0]);
			    Dst = Builder.CreatePointerCast(Dst, PointerType::getUnqual(Type::getInt8Ty(Context)));
			    Value *Val = convertOperand(func, Type::getInt8Ty(Context), inst->u.three[1]);
			    Value *Len = convertOperand(func, Type::getInt32Ty(Context), inst->u.three[2]);
#if LLVM_VERSION < 29
			    CallInst *c = Builder.CreateCall4(CF->FMemset, Dst, Val, Len,
								ConstantInt::get(Type::getInt32Ty(Context), 1));
#else
			    CallInst *c = Builder.CreateCall5(CF->FMemset, Dst, Val, Len,
								ConstantInt::get(Type::getInt32Ty(Context), 1),
								ConstantInt::get(Type::getInt1Ty(Context), 0)
								);
#endif
			    c->setTailCall(true);
			    c->setDoesNotThrow();
			    UpgradeCall(c, CF->FMemset);
			    break;
			}
			case OP_BC_MEMCPY:
			{
			    Value *Dst = convertOperand(func, inst, inst->u.three[0]);
			    Dst = Builder.CreatePointerCast(Dst, PointerType::getUnqual(Type::getInt8Ty(Context)));
			    Value *Src = convertOperand(func, inst, inst->u.three[1]);
			    Src = Builder.CreatePointerCast(Src, PointerType::getUnqual(Type::getInt8Ty(Context)));
			    Value *Len = convertOperand(func, Type::getInt32Ty(Context), inst->u.three[2]);
#if LLVM_VERSION < 29
			    CallInst *c = Builder.CreateCall4(CF->FMemcpy, Dst, Src, Len,
								ConstantInt::get(Type::getInt32Ty(Context), 1));
#else
			    CallInst *c = Builder.CreateCall5(CF->FMemcpy, Dst, Src, Len,
								ConstantInt::get(Type::getInt32Ty(Context), 1),
								ConstantInt::get(Type::getInt1Ty(Context), 0)
								);
#endif
			    c->setTailCall(true);
			    c->setDoesNotThrow();
			    UpgradeCall(c, CF->FMemcpy);
			    break;
			}
			case OP_BC_MEMMOVE:
			{
			    Value *Dst = convertOperand(func, inst, inst->u.three[0]);
			    Dst = Builder.CreatePointerCast(Dst, PointerType::getUnqual(Type::getInt8Ty(Context)));
			    Value *Src = convertOperand(func, inst, inst->u.three[1]);
			    Src = Builder.CreatePointerCast(Src, PointerType::getUnqual(Type::getInt8Ty(Context)));
			    Value *Len = convertOperand(func, Type::getInt32Ty(Context), inst->u.three[2]);
#if LLVM_VERSION < 29
			    CallInst *c = Builder.CreateCall4(CF->FMemmove, Dst, Src, Len,
								ConstantInt::get(Type::getInt32Ty(Context), 1));
#else
			    CallInst *c = Builder.CreateCall5(CF->FMemmove, Dst, Src, Len,
								ConstantInt::get(Type::getInt32Ty(Context), 1),
								ConstantInt::get(Type::getInt1Ty(Context), 0));
#endif
			    c->setTailCall(true);
			    c->setDoesNotThrow();
			    UpgradeCall(c, CF->FMemmove);
			    break;
			}
			case OP_BC_MEMCMP:
			{
			    Value *Dst = convertOperand(func, inst, inst->u.three[0]);
			    Dst = Builder.CreatePointerCast(Dst, PointerType::getUnqual(Type::getInt8Ty(Context)));
			    Value *Src = convertOperand(func, inst, inst->u.three[1]);
			    Src = Builder.CreatePointerCast(Src, PointerType::getUnqual(Type::getInt8Ty(Context)));
#if LLVM_VERSION < 32
			    Value *Len = convertOperand(func, EE->getTargetData()->getIntPtrType(Context), inst->u.three[2]);
#else
			    Value *Len = convertOperand(func, EE->getDataLayout()->getIntPtrType(Context), inst->u.three[2]);
#endif
			    CallInst *c = Builder.CreateCall3(CF->FRealmemcmp, Dst, Src, Len);
			    c->setTailCall(true);
			    c->setDoesNotThrow();
			    Store(inst->dest, c);
			    break;
			}
			case OP_BC_ISBIGENDIAN:
			    Store(inst->dest, WORDS_BIGENDIAN ?
				  ConstantInt::getTrue(Context) :
				  ConstantInt::getFalse(Context));
			    break;
			case OP_BC_ABORT:
			    if (!unreachable) {
				CallInst *CI = Builder.CreateCall(CF->FHandler);
				CI->setDoesNotReturn();
				CI->setDoesNotThrow();
				Builder.CreateUnreachable();
				unreachable = true;
			    }
			    break;
			case OP_BC_BSWAP16:
			    {
				CallInst *C = Builder.CreateCall(CF->FBSwap16, convertOperand(func, inst, inst->u.unaryop));
				C->setTailCall(true);
#if LLVM_VERSION < 32
				C->setDoesNotThrow(true);
#else
				C->setDoesNotThrow();
#endif
				Store(inst->dest, C);
				break;
			    }
			case OP_BC_BSWAP32:
			    {
				CallInst *C = Builder.CreateCall(CF->FBSwap32, convertOperand(func, inst, inst->u.unaryop));
				C->setTailCall(true);
#if LLVM_VERSION < 32
				C->setDoesNotThrow(true);
#else
				C->setDoesNotThrow();
#endif
				Store(inst->dest, C);
				break;
			    }
			case OP_BC_BSWAP64:
			    {
				CallInst *C = Builder.CreateCall(CF->FBSwap64, convertOperand(func, inst, inst->u.unaryop));
				C->setTailCall(true);
#if LLVM_VERSION < 32
				C->setDoesNotThrow(true);
#else
				C->setDoesNotThrow();
#endif
				Store(inst->dest, C);
				break;
			    }
			case OP_BC_PTRDIFF32:
			    {
				Value *P1 = convertOperand(func, inst, inst->u.binop[0]);
				Value *P2 = convertOperand(func, inst, inst->u.binop[1]);
				P1 = Builder.CreatePtrToInt(P1, Type::getInt64Ty(Context));
				P2 = Builder.CreatePtrToInt(P2, Type::getInt64Ty(Context));
				Value *R = Builder.CreateSub(P1, P2);
				R = Builder.CreateTrunc(R, Type::getInt32Ty(Context));
				Store(inst->dest, R);
				break;
			    }
			case OP_BC_PTRTOINT64:
			    {
				Value *P1 = convertOperand(func, inst, inst->u.unaryop);
				P1 = Builder.CreatePtrToInt(P1, Type::getInt64Ty(Context));
				Store(inst->dest, P1);
				break;
			    }
			default:
			    cli_warnmsg("[Bytecode JIT]: JIT doesn't implement opcode %d yet!\n",
					inst->opcode);
			    broken = true;
			    break;
		    }
		}
	    }

	    // If successful so far, run verifyFunction
	    if (!broken) {
#if LLVM_VERSION < 35
		if (verifyFunction(*F, PrintMessageAction)) {
#else
		if (verifyFunction(*F, &errs())) {
#endif
		    // verification failed
		    broken = true;
		    cli_warnmsg("[Bytecode JIT]: Verification failed\n");
		    if (cli_debug_flag) {
			std::string str;
			raw_string_ostream ostr(str);
			F->print(ostr);
			cli_dbgmsg_internal("[Bytecode JIT]: %s\n", ostr.str().c_str());
		    }
		}
	    }

	    delete [] Values;

	    // Cleanup after failure and return 0
	    if (broken) {
		for (unsigned z=0; z < func->numBB ; z++) {
		    delete BB[z];
		}
		delete [] BB;
		apiMap.irgenTimer.stopTimer();
		delete TypeMap;
		for (unsigned z=0; z < bc->num_func; z++) {
		    delete Functions[z];
		}
		delete [] Functions;
		return 0;
	    }

	    delete [] BB;
	    apiMap.irgenTimer.stopTimer();
	    apiMap.pmTimer.startTimer();
	    if (bc->trusted) {
		PM.doInitialization();
		PM.run(*F);
		PM.doFinalization();
	    }
	    else {
		PMUnsigned.doInitialization();
		PMUnsigned.run(*F);
		PMUnsigned.doFinalization();
	    }
	    apiMap.pmTimer.stopTimer();
	    apiMap.irgenTimer.startTimer();
	}

	for (unsigned j=0;j<bc->num_func;j++) {
	    Function *F = Functions[j];
	    AddStackProtect(F);
	}
	delete TypeMap;
	std::vector<constType*> args;
	args.clear();
	args.push_back(HiddenCtx);
	FunctionType *Callable = FunctionType::get(Type::getInt32Ty(Context),
						   args, false);

	// If prototype matches, add to callable functions
	if (Functions[0]->getFunctionType() != Callable) {
	    cli_warnmsg("[Bytecode JIT]: Wrong prototype for function 0 in bytecode %d\n",  bc->id);
	    apiMap.irgenTimer.stopTimer();
	    for (unsigned z=0; z < bc->num_func; z++) {
		delete Functions[z];
	    }
	    delete [] Functions;
	    return 0;
	}
	// All functions have the Fast calling convention, however
	// entrypoint can only be C, emit wrapper
	Function *F = Function::Create(Functions[0]->getFunctionType(),
				       Function::ExternalLinkage,
#if LLVM_VERSION < 33
				       Functions[0]->getName()+"_wrap", M);
#else
				       Functions[0]->getName().str()+"_wrap", M);
#endif
	F->setDoesNotThrow();
	BasicBlock *BB = BasicBlock::Create(Context, "", F);
	std::vector<Value*> Args;
	for (Function::arg_iterator J=F->arg_begin(),
	     JE=F->arg_end(); J != JE; ++JE) {
	    Args.push_back(&*J);
	}
	CallInst *CI = CallInst::Create(Functions[0], ARRAYREFVECTOR(Value*, Args), "", BB);
	CI->setCallingConv(CallingConv::Fast);
	ReturnInst::Create(Context, CI, BB);

	delete [] Functions;
#if LLVM_VERSION < 35
	if (verifyFunction(*F, PrintMessageAction))
#else
	if (verifyFunction(*F, &errs()))
#endif
	    return 0;

/*			DEBUG(errs() << "Generating code\n");
			// Codegen current function as executable machine code.
			EE->getPointerToFunction(Functions[j]);
			void *code = EE->getPointerToFunction(F);
			DEBUG(errs() << "Code generation finished\n");*/

//		compiledFunctions[func] = code;
	apiMap.irgenTimer.stopTimer();
	return F;
    }
};

static sys::Mutex llvm_api_lock;

// This class automatically acquires the lock when instantiated,
// and releases the lock when leaving scope.
class LLVMApiScopedLock {
    public:
	// when multithreaded mode is false (no atomics available),
	// we need to wrap all LLVM API calls with a giant mutex lock, but
	// only then.
	LLVMApiScopedLock() {
	    // It is safer to just run all codegen under the mutex,
	    // it is not like we are going to codegen from multiple threads
	    // at a time anyway.
//	    if (!llvm_is_multithreaded())
#if LLVM_VERSION < 36
		llvm_api_lock.acquire();
#else
		llvm_api_lock.lock();
#endif
	}
	~LLVMApiScopedLock() {
//	    if (!llvm_is_multithreaded())
#if LLVM_VERSION < 36
		llvm_api_lock.release();
#else
		llvm_api_lock.unlock();
#endif
	}
};

static void addFunctionProtos(struct CommonFunctions *CF, ExecutionEngine *EE, Module *M)
{
    LLVMContext &Context = M->getContext();
    FunctionType *FTy = FunctionType::get(Type::getVoidTy(Context),
					  false);
    CF->FHandler = Function::Create(FTy, Function::ExternalLinkage,
					  "clamjit.fail", M);
    CF->FHandler->setDoesNotReturn();
    CF->FHandler->setDoesNotThrow();
#if LLVM_VERSION == 32
    CF->FHandler->addFnAttr(Attributes::NoInline);
#else
    CF->FHandler->addFnAttr(Attribute::NoInline);
#endif
#if LLVM_VERSION < 36
    // addGlobalMapping still exists in LLVM 3.6, but it doesn't work with MCJIT, which now replaces the JIT implementation.
    EE->addGlobalMapping(CF->FHandler, (void*)(intptr_t)jit_exception_handler);
#else
    sys::DynamicLibrary::AddSymbol(CF->FHandler->getName(), (void*)(intptr_t)jit_exception_handler);
#endif
    EE->InstallLazyFunctionCreator(noUnknownFunctions);
    EE->getPointerToFunction(CF->FHandler);

    std::vector<constType*> args;
    args.push_back(PointerType::getUnqual(Type::getInt8Ty(Context)));
    args.push_back(Type::getInt8Ty(Context));
    args.push_back(Type::getInt32Ty(Context));
    args.push_back(Type::getInt32Ty(Context));
#if LLVM_VERSION >= 29
    args.push_back(Type::getInt1Ty(Context));
#endif
    FunctionType* FuncTy_3 = FunctionType::get(Type::getVoidTy(Context),
					       args, false);
    CF->FMemset = Function::Create(FuncTy_3, GlobalValue::ExternalLinkage,
#if LLVM_VERSION < 29
                                   "llvm.memset.i32",
#else
                                   "llvm.memset.p0i8.i32",
#endif
                                   M);
    CF->FMemset->setDoesNotThrow();
#if LLVM_VERSION < 32
    CF->FMemset->setDoesNotCapture(1, true);
#else
    CF->FMemset->setDoesNotCapture(1);
#endif

    args.clear();
    args.push_back(PointerType::getUnqual(Type::getInt8Ty(Context)));
    args.push_back(PointerType::getUnqual(Type::getInt8Ty(Context)));
    args.push_back(Type::getInt32Ty(Context));
    args.push_back(Type::getInt32Ty(Context));
#if LLVM_VERSION >= 29
    args.push_back(Type::getInt1Ty(Context));
#endif
    FunctionType* FuncTy_4 = FunctionType::get(Type::getVoidTy(Context),
					       args, false);
    CF->FMemmove = Function::Create(FuncTy_4, GlobalValue::ExternalLinkage,
#if LLVM_VERSION < 29
                                    "llvm.memmove.i32",
#else
                                    "llvm.memmove.p0i8.i32",
#endif
                                    M);
    CF->FMemmove->setDoesNotThrow();
#if LLVM_VERSION < 32
    CF->FMemmove->setDoesNotCapture(1, true);
#else
    CF->FMemmove->setDoesNotCapture(1);
#endif

    CF->FMemcpy = Function::Create(FuncTy_4, GlobalValue::ExternalLinkage,
#if LLVM_VERSION < 29
                                   "llvm.memcpy.i32",
#else
                                   "llvm.memcpy.p0i8.p0i8.i32",
#endif
                                   M);
    CF->FMemcpy->setDoesNotThrow();
#if LLVM_VERSION < 32
    CF->FMemcpy->setDoesNotCapture(1, true);
#else
    CF->FMemcpy->setDoesNotCapture(1);
#endif

    args.clear();
    args.push_back(Type::getInt16Ty(Context));
    FunctionType *FuncTy_5 = FunctionType::get(Type::getInt16Ty(Context), args, false);
    CF->FBSwap16 = Function::Create(FuncTy_5, GlobalValue::ExternalLinkage,
					  "llvm.bswap.i16", M);
    CF->FBSwap16->setDoesNotThrow();

    args.clear();
    args.push_back(Type::getInt32Ty(Context));
    FunctionType *FuncTy_6 = FunctionType::get(Type::getInt32Ty(Context), args, false);
    CF->FBSwap32 = Function::Create(FuncTy_6, GlobalValue::ExternalLinkage,
					  "llvm.bswap.i32", M);
    CF->FBSwap32->setDoesNotThrow();

    args.clear();
    args.push_back(Type::getInt64Ty(Context));
    FunctionType *FuncTy_7 = FunctionType::get(Type::getInt64Ty(Context), args, false);
    CF->FBSwap64 = Function::Create(FuncTy_7, GlobalValue::ExternalLinkage,
					  "llvm.bswap.i64", M);
    CF->FBSwap64->setDoesNotThrow();

    FunctionType* DummyTy = FunctionType::get(Type::getVoidTy(Context), false);
    CF->FRealmemset = Function::Create(DummyTy, GlobalValue::ExternalLinkage,
					     "memset", M);
#if LLVM_VERSION < 36
    EE->addGlobalMapping(CF->FRealmemset, (void*)(intptr_t)memset);
#else
    sys::DynamicLibrary::AddSymbol(CF->FRealmemset->getName(), (void*)(intptr_t)memset);
#endif
    EE->getPointerToFunction(CF->FRealmemset);
    CF->FRealMemmove = Function::Create(DummyTy, GlobalValue::ExternalLinkage,
					      "memmove", M);
#if LLVM_VERSION < 36
    EE->addGlobalMapping(CF->FRealMemmove, (void*)(intptr_t)memmove);
#else
    sys::DynamicLibrary::AddSymbol(CF->FRealMemmove->getName(), (void*)(intptr_t)memmove);
#endif
    EE->getPointerToFunction(CF->FRealMemmove);
    CF->FRealmemcpy = Function::Create(DummyTy, GlobalValue::ExternalLinkage,
					     "memcpy", M);
#if LLVM_VERSION < 36
    EE->addGlobalMapping(CF->FRealmemcpy, (void*)(intptr_t)memcpy);
#else
    sys::DynamicLibrary::AddSymbol(CF->FRealmemcpy->getName(), (void*)(intptr_t)memcpy);
#endif
    EE->getPointerToFunction(CF->FRealmemcpy);

    args.clear();
    args.push_back(PointerType::getUnqual(Type::getInt8Ty(Context)));
    args.push_back(PointerType::getUnqual(Type::getInt8Ty(Context)));
#if LLVM_VERSION < 32
    args.push_back(EE->getTargetData()->getIntPtrType(Context));
#else
    args.push_back(EE->getDataLayout()->getIntPtrType(Context));
#endif
    FuncTy_5 = FunctionType::get(Type::getInt32Ty(Context),
				 args, false);
    CF->FRealmemcmp = Function::Create(FuncTy_5, GlobalValue::ExternalLinkage, "memcmp", M);
#if LLVM_VERSION < 36
    EE->addGlobalMapping(CF->FRealmemcmp, (void*)(intptr_t)memcmp);
#else
    sys::DynamicLibrary::AddSymbol(CF->FRealmemcmp->getName(), (void*)(intptr_t)memcmp);
#endif
    EE->getPointerToFunction(CF->FRealmemcmp);
}

}
#if LLVM_VERSION >= 29
INITIALIZE_PASS_BEGIN(RuntimeLimits, "rl", "Runtime Limits", false, false)
INITIALIZE_PASS_DEPENDENCY(LoopInfo)
INITIALIZE_PASS_DEPENDENCY(ScalarEvolution)
#if LLVM_VERSION < 35
INITIALIZE_PASS_DEPENDENCY(DominatorTree)
#else
INITIALIZE_PASS_DEPENDENCY(DominatorTreeWrapperPass)
#endif
INITIALIZE_PASS_END(RuntimeLimits, "rl" ,"Runtime Limits", false, false)
#endif

static pthread_mutex_t watchdog_mutex = PTHREAD_MUTEX_INITIALIZER;
static pthread_cond_t watchdog_cond = PTHREAD_COND_INITIALIZER;
static pthread_cond_t watchdog_cond2 = PTHREAD_COND_INITIALIZER;
static int watchdog_running = 0;

struct watchdog_item {
    volatile uint8_t* timeout;
    struct timespec abstimeout;
    struct watchdog_item *next;
    int in_use;
};

static struct watchdog_item* watchdog_head = NULL;
static struct watchdog_item* watchdog_tail = NULL;

extern "C" const char *cli_strerror(int errnum, char* buf, size_t len);
#define WATCHDOG_IDLE 10
static void *bytecode_watchdog(void *arg)
{
    struct timeval tv;
    struct timespec out;
    int ret;
    char err[128];
    pthread_mutex_lock(&watchdog_mutex);
    if (cli_debug_flag)
	cli_dbgmsg_internal("bytecode watchdog is running\n");
    do {
	struct watchdog_item *item;
	gettimeofday(&tv, NULL);
	out.tv_sec = tv.tv_sec + WATCHDOG_IDLE;
	out.tv_nsec = tv.tv_usec*1000;
	/* wait for some work, up to WATCHDOG_IDLE time */
	while (watchdog_head == NULL) {
	    ret = pthread_cond_timedwait(&watchdog_cond, &watchdog_mutex,
					 &out);
	    if (ret == ETIMEDOUT)
		break;
	    if (ret) {
		cli_warnmsg("bytecode_watchdog: cond_timedwait(1) failed: %s\n",
			    cli_strerror(ret, err, sizeof(err)));
		break;
	    }
	}
	if (watchdog_head == NULL)
	    break;
	/* wait till timeout is reached on this item */
	item = watchdog_head;
	while (item == watchdog_head) {
	    item->in_use = 1;
	    ret = pthread_cond_timedwait(&watchdog_cond, &watchdog_mutex,
					 &item->abstimeout);
	    if (ret == ETIMEDOUT)
		break;
	    if (ret) {
		cli_warnmsg("bytecode_watchdog: cond_timedwait(2) failed: %s\n",
			    cli_strerror(ret, err, sizeof(err)));
		break;
	    }
	}
	item->in_use = 0;
	pthread_cond_signal(&watchdog_cond2);
	if (item != watchdog_head)
	    continue;/* got removed meanwhile */
	/* timeout reached, signal it to bytecode */
	*item->timeout = 1;
	cli_warnmsg("[Bytecode JIT]: Bytecode run timed out, timeout flag set\n");
	watchdog_head = item->next;
	if (!watchdog_head)
	    watchdog_tail = NULL;
    } while (1);
    watchdog_running = 0;
    if (cli_debug_flag)
	cli_dbgmsg_internal("bytecode watchdog quiting\n");
    pthread_mutex_unlock(&watchdog_mutex);
    return NULL;
}

static void watchdog_disarm(struct watchdog_item *item)
{
    struct watchdog_item *q, *p = NULL;
    if (!item)
	return;
    pthread_mutex_lock(&watchdog_mutex);
    for (q=watchdog_head;q && q != item;p = q, q = q->next) {}
    if (q == item) {
	if (p)
	    p->next = q->next;
	if (q == watchdog_head)
	    watchdog_head = q->next;
	if (q == watchdog_tail)
	    watchdog_tail = p;
    }
    /* don't remove the item from the list until the watchdog is sleeping on
     * item, or it'll wake up on uninit data */
    while (item->in_use) {
	pthread_cond_signal(&watchdog_cond);
	pthread_cond_wait(&watchdog_cond2, &watchdog_mutex);
    }
    pthread_mutex_unlock(&watchdog_mutex);
}

static int watchdog_arm(struct watchdog_item *item, int ms, volatile uint8_t *timeout)
{
    int rc = 0;
    struct timeval tv0;

    *timeout = 0;
    item->timeout = timeout;
    item->next = NULL;
    item->in_use = 0;

    gettimeofday(&tv0, NULL);
    tv0.tv_usec += ms * 1000;
    item->abstimeout.tv_sec = tv0.tv_sec + tv0.tv_usec/1000000;
    item->abstimeout.tv_nsec = (tv0.tv_usec%1000000)*1000;

    pthread_mutex_lock(&watchdog_mutex);
    if (!watchdog_running) {
	pthread_t thread;
	pthread_attr_t attr;
	pthread_attr_init(&attr);
	pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);

	if ((rc = pthread_create(&thread, &attr, bytecode_watchdog, NULL))) {
	    char buf[256];
	    cli_errmsg("(watchdog) pthread_create failed: %s\n", cli_strerror(rc, buf, sizeof(buf)));
	}
	if (!rc)
	    watchdog_running = 1;
	pthread_attr_destroy(&attr);
    }
    if (!rc) {
	if (watchdog_tail)
	    watchdog_tail->next = item;
	watchdog_tail = item;
	if (!watchdog_head)
	    watchdog_head = item;
    }
    pthread_cond_signal(&watchdog_cond);
    pthread_mutex_unlock(&watchdog_mutex);
    return rc;
}

static int bytecode_execute(intptr_t code, struct cli_bc_ctx *ctx)
{
    ScopedExceptionHandler handler;
    // execute;
    HANDLER_TRY(handler) {
	// setup exception handler to longjmp back here
	uint32_t result = ((uint32_t (*)(struct cli_bc_ctx *))(intptr_t)code)(ctx);
	*(uint32_t*)ctx->values = result;
	return 0;
    }
    HANDLER_END(handler);
    cli_warnmsg("[Bytecode JIT]: JITed code intercepted runtime error!\n");
    return CL_EBYTECODE;
}

int cli_vm_execute_jit(const struct cli_all_bc *bcs, struct cli_bc_ctx *ctx,
		       const struct cli_bc_func *func)
{
    int ret;
    struct timeval tv0, tv1;
    struct watchdog_item witem;
    // no locks needed here, since LLVM automatically acquires a JIT lock
    // if needed.
    void *code = bcs->engine->compiledFunctions[func];
    if (!code) {
	cli_warnmsg("[Bytecode JIT]: Unable to find compiled function\n");
	if (func->numArgs)
	    cli_warnmsg("[Bytecode JIT] Function has %d arguments, it must have 0 to be called as entrypoint\n",
			func->numArgs);
	return CL_EBYTECODE;
    }
    if (cli_debug_flag)
	gettimeofday(&tv0, NULL);

    if (ctx->bytecode_timeout) {
	/* only spawn if timeout is set.
	 * we don't set timeout for selfcheck (see bb #2235) */
	if (watchdog_arm(&witem, ctx->bytecode_timeout, &ctx->timeout))
	    return CL_EBYTECODE;
    }

    ret = bytecode_execute((intptr_t)code, ctx);

    if (ctx->bytecode_timeout)
	watchdog_disarm(&witem);

    if (cli_debug_flag) {
	long diff;
	gettimeofday(&tv1, NULL);
	tv1.tv_sec -= tv0.tv_sec;
	tv1.tv_usec -= tv0.tv_usec;
	diff = tv1.tv_sec*1000000 + tv1.tv_usec;
	cli_dbgmsg_internal("bytecode finished in %ld us\n", diff);
    }
    return ctx->timeout ? CL_ETIMEOUT : ret;
}

static unsigned char name_salt[16] = { 16, 38, 97, 12, 8, 4, 72, 196, 217, 144, 33, 124, 18, 11, 17, 253 };
static void setGuard(unsigned char* guardbuf)
{
    char salt[48];
    memcpy(salt, name_salt, 16);
    for(unsigned i = 16; i < 48; i++)
	salt[i] = cli_rndnum(255);

    cl_hash_data("md5", salt, 48, guardbuf, NULL);
}
#if LLVM_VERSION < 32
static void addFPasses(FunctionPassManager &FPM, bool trusted, const TargetData *TD)
#elif LLVM_VERSION < 35
static void addFPasses(FunctionPassManager &FPM, bool trusted, const DataLayout *TD)
#elif LLVM_VERSION < 36
static void addFPasses(FunctionPassManager &FPM, bool trusted, const Module *M)
#else
static void addFPasses(FunctionPassManager &FPM, bool trusted, Module *M)
#endif
{
    // Set up the optimizer pipeline.  Start with registering info about how
    // the target lays out data structures.
#if LLVM_VERSION < 32
    FPM.add(new TargetData(*TD));
#elif LLVM_VERSION < 35
    FPM.add(new DataLayout(*TD));
#elif LLVM_VERSION < 36
    FPM.add(new DataLayoutPass(M));
#else
    DataLayoutPass *DLP = new DataLayoutPass();
    DLP->doInitialization(*M);
    FPM.add(DLP);
#endif
    // Promote allocas to registers.
    FPM.add(createPromoteMemoryToRegisterPass());
    FPM.add(new BrSimplifier());
    FPM.add(createDeadCodeEliminationPass());
}

int cli_bytecode_prepare_jit(struct cli_all_bc *bcs)
{
  if (!bcs->engine)
      return CL_EBYTECODE;
  ScopedExceptionHandler handler;
  LLVMApiScopedLock scopedLock;
  // setup exception handler to longjmp back here
  HANDLER_TRY(handler) {
  // LLVM itself never throws exceptions, but operator new may throw bad_alloc
  try {
    Module *M = new Module("ClamAV jit module", bcs->engine->Context);
    {
	// Create the JIT.
	std::string ErrorMsg;
#if LLVM_VERSION < 36
	EngineBuilder builder(M);
#else
	EngineBuilder builder(std::move(std::unique_ptr<Module>(M)));
#endif

#if LLVM_VERSION >= 31
	TargetOptions Options;
#ifdef CL_DEBUG
	//disable this for now, it leaks
	Options.JITEmitDebugInfo = false;
//	Options.JITEmitDebugInfo = true;
#else
	Options.JITEmitDebugInfo = false;
#endif
#if LLVM_VERSION < 34
	Options.DwarfExceptionHandling = false;
#else
	// TODO: How to do this now?
#endif
	builder.setTargetOptions(Options);
#endif

	builder.setErrorStr(&ErrorMsg);
	builder.setEngineKind(EngineKind::JIT);
	builder.setOptLevel(CodeGenOpt::Default);
	ExecutionEngine *EE = bcs->engine->EE = builder.create();
	if (!EE) {
	    if (!ErrorMsg.empty())
		cli_errmsg("[Bytecode JIT]: error creating execution engine: %s\n",
			   ErrorMsg.c_str());
	    else
		cli_errmsg("[Bytecode JIT]: JIT not registered?\n");
	    return CL_EBYTECODE;
	}
	bcs->engine->Listener  = new NotifyListener();
	EE->RegisterJITEventListener(bcs->engine->Listener);
//	EE->RegisterJITEventListener(createOProfileJITEventListener());
	// Due to LLVM PR4816 only X86 supports non-lazy compilation, disable
	// for now.
	EE->DisableLazyCompilation();
#if LLVM_VERSION < 36
	EE->DisableSymbolSearching();
#else
	// This must be enabled for AddSymbol to work.
	EE->DisableSymbolSearching(false);
#endif

	struct CommonFunctions CF;
	addFunctionProtos(&CF, EE, M);

	FunctionPassManager OurFPM(M), OurFPMUnsigned(M);
#if LLVM_VERSION < 32
	M->setDataLayout(EE->getTargetData()->getStringRepresentation());
#else
	M->setDataLayout(EE->getDataLayout()->getStringRepresentation());
#endif
#if LLVM_VERSION < 31
	M->setTargetTriple(sys::getHostTriple());
#else
	M->setTargetTriple(sys::getDefaultTargetTriple());
#endif
#if LLVM_VERSION < 32
	addFPasses(OurFPM, true, EE->getTargetData());
	addFPasses(OurFPMUnsigned, false, EE->getTargetData());
#elif LLVM_VERSION < 35
	addFPasses(OurFPM, true, EE->getDataLayout());
	addFPasses(OurFPMUnsigned, false, EE->getDataLayout());
#else
	addFPasses(OurFPM, true, M);
	addFPasses(OurFPMUnsigned, false, M);
#endif


	//TODO: create a wrapper that calls pthread_getspecific
	unsigned maxh = cli_globals[0].offset + sizeof(struct cli_bc_hooks);
	constType *HiddenCtx = PointerType::getUnqual(ArrayType::get(Type::getInt8Ty(bcs->engine->Context), maxh));

	LLVMTypeMapper apiMap(bcs->engine->Context, cli_apicall_types, cli_apicall_maxtypes, HiddenCtx);
	Function **apiFuncs = new Function *[cli_apicall_maxapi];
	for (unsigned i=0;i<cli_apicall_maxapi;i++) {
	    const struct cli_apicall *api = &cli_apicalls[i];
	    constFunctionType *FTy = cast<FunctionType>(apiMap.get(69+api->type, NULL, NULL));
	    Function *F = Function::Create(FTy, Function::ExternalLinkage,
					   api->name, M);
	    void *dest;
	    switch (api->kind) {
		case 0:
		    dest = (void*)(intptr_t)cli_apicalls0[api->idx];
		    break;
		case 1:
		    dest = (void*)(intptr_t)cli_apicalls1[api->idx];
		    break;
		case 2:
		    dest = (void*)(intptr_t)cli_apicalls2[api->idx];
		    break;
		case 3:
		    dest = (void*)(intptr_t)cli_apicalls3[api->idx];
		    break;
		case 4:
		    dest = (void*)(intptr_t)cli_apicalls4[api->idx];
		    break;
		case 5:
		    dest = (void*)(intptr_t)cli_apicalls5[api->idx];
		    break;
		case 6:
		    dest = (void*)(intptr_t)cli_apicalls6[api->idx];
		    break;
		case 7:
		    dest = (void*)(intptr_t)cli_apicalls7[api->idx];
		    break;
		case 8:
		    dest = (void*)(intptr_t)cli_apicalls8[api->idx];
		    break;
		case 9:
		    dest = (void*)(intptr_t)cli_apicalls9[api->idx];
		    break;
		default:
		    llvm_unreachable("invalid api type");
	    }
	    if (!dest) {
		std::string reason((Twine("No mapping for builtin api ")+api->name).str());
		llvm_error_handler(0, reason);
	    }
#if LLVM_VERSION < 36
	    EE->addGlobalMapping(F, dest);
#else
    // addGlobalMapping doesn't work with MCJIT, so use symbol searching instead.
    sys::DynamicLibrary::AddSymbol(F->getName(), dest);
#endif
	    EE->getPointerToFunction(F);
	    apiFuncs[i] = F;
	}

	// stack protector
	FunctionType *FTy = FunctionType::get(Type::getVoidTy(M->getContext()),
						    false);
	GlobalVariable *Guard = new GlobalVariable(*M, PointerType::getUnqual(Type::getInt8Ty(M->getContext())),
						    true, GlobalValue::ExternalLinkage, 0, "__stack_chk_guard");
	unsigned plus = 0;
	if (2*sizeof(void*) <= 16 && cli_rndnum(2)==2) {
	    plus = sizeof(void*);
	}
#if LLVM_VERSION < 36
	EE->addGlobalMapping(Guard, (void*)(&bcs->engine->guard.b[plus]));
#else
    sys::DynamicLibrary::AddSymbol(Guard->getName(), (void*)(&bcs->engine->guard.b[plus]));
#endif
	setGuard(bcs->engine->guard.b);
	bcs->engine->guard.b[plus+sizeof(void*)-1] = 0x00;
//	printf("%p\n", *(void**)(&bcs->engine->guard.b[plus]));
	Function *SFail = Function::Create(FTy, Function::ExternalLinkage,
					      "__stack_chk_fail", M);
#if LLVM_VERSION < 36
	EE->addGlobalMapping(SFail, (void*)(intptr_t)jit_ssp_handler);
#else
    sys::DynamicLibrary::AddSymbol(SFail->getName(), (void*)(intptr_t)jit_ssp_handler);
#endif
        EE->getPointerToFunction(SFail);

	llvm::Function **Functions = new Function*[bcs->count];
	for (unsigned i=0;i<bcs->count;i++) {
	    const struct cli_bc *bc = &bcs->all_bcs[i];
	    if (bc->state == bc_skip || bc->state == bc_interp) {
		Functions[i] = 0;
		continue;
	    }
	    LLVMCodegen Codegen(bc, M, &CF, bcs->engine->compiledFunctions, EE,
				OurFPM, OurFPMUnsigned, apiFuncs, apiMap);
	    Function *F = Codegen.generate();
	    if (!F) {
		cli_errmsg("[Bytecode JIT]: JIT codegen failed\n");
		delete [] apiFuncs;
		for (unsigned z=0; z < i; z++) {
		    delete Functions[z];
		}
		delete [] Functions;
		return CL_EBYTECODE;
	    }
	    Functions[i] = F;
	}
	delete [] apiFuncs;

	bool has_untrusted = false;

	for (unsigned i=0;i<bcs->count;i++) {
	    if (!bcs->all_bcs[i].trusted) {
		has_untrusted = true;
		break;
	    }
	}
	PassManager PM;
#if LLVM_VERSION < 32
	PM.add(new TargetData(*EE->getTargetData()));
#elif LLVM_VERSION < 35
	PM.add(new DataLayout(*EE->getDataLayout()));
#elif LLVM_VERSION < 36
	PM.add(new DataLayoutPass(M));
#else
    DataLayoutPass *DLP = new DataLayoutPass();
    DLP->doInitialization(*M);
    PM.add(DLP);
#endif
	// TODO: only run this on the untrusted bytecodes, not all of them...
	if (has_untrusted)
	    PM.add(createClamBCRTChecks());
#if LLVM_VERSION >= 36
	// With LLVM 3.6 (MCJIT) this Pass is required to work around
	// a crash in LLVM caused by the SCCP Pass:
	// Pass 'Sparse Conditional Constant Propagation' is not initialized.
	// Verify if there is a pass dependency cycle.
	// Required Passes:
	//
	// Program received signal SIGSEGV, Segmentation fault.
	PM.add(createGVNPass());
#endif
	PM.add(createSCCPPass());
	PM.add(createCFGSimplificationPass());
	PM.add(createGlobalOptimizerPass());
	PM.add(createConstantMergePass());

	RuntimeLimits *RL = new RuntimeLimits();
	PM.add(RL);
	TimerWrapper pmTimer2("Transform passes");
	pmTimer2.startTimer();
	PM.run(*M);
	pmTimer2.stopTimer();
	DEBUG(M->dump());

#if LLVM_VERSION >= 36
	EE->finalizeObject();
#endif

	{
	    PrettyStackTraceString CrashInfo2("Native machine codegen");
	    TimerWrapper codegenTimer("Native codegen");
	    codegenTimer.startTimer();
	    // compile all functions now, not lazily!
	    for (Module::iterator I = M->begin(), E = M->end(); I != E; ++I) {
		Function *Fn = &*I;
		if (!Fn->isDeclaration()) {
		    EE->getPointerToFunction(Fn);
		}
	    }
	    codegenTimer.stopTimer();
	}

	for (unsigned i=0;i<bcs->count;i++) {
	    const struct cli_bc_func *func = &bcs->all_bcs[i].funcs[0];
	    if (!Functions[i])
		continue;// not JITed
	    bcs->engine->compiledFunctions[func] = EE->getPointerToFunction(Functions[i]);
	    bcs->all_bcs[i].state = bc_jit;
	}
	delete [] Functions;
    }
    return CL_SUCCESS;
  } catch (std::bad_alloc &badalloc) {
      cli_errmsg("[Bytecode JIT]: bad_alloc: %s\n",
		 badalloc.what());
      return CL_EMEM;
  } catch (...) {
      cli_errmsg("[Bytecode JIT]: Unexpected unknown exception occured\n");
      return CL_EBYTECODE;
  }
  return 0;
  } HANDLER_END(handler);
  cli_errmsg("[Bytecode JIT] *** FATAL error encountered during bytecode generation\n");
  return CL_EBYTECODE;
}

int bytecode_init(void)
{
    // If already initialized return
#if LLVM_VERSION < 35
    if (llvm_is_multithreaded()) {
	cli_warnmsg("bytecode_init: already initialized\n");
	return CL_EARG;
    }
#else
    if (!LLVMIsMultithreaded()) {
        cli_warnmsg("bytecode_init: LLVM is compiled without multithreading support\n");
    }
#endif

    // LLVM safety assertion prevention fix
    // TODO: do we want to do a full shutdown?
    remove_fatal_error_handler();
    llvm_install_error_handler(llvm_error_handler);
#ifdef CL_DEBUG
    sys::PrintStackTraceOnErrorSignal();
#if LLVM_VERSION >= 34
    llvm::EnablePrettyStackTrace();
#endif
#else
#if LLVM_VERSION < 34
    llvm::DisablePrettyStackTrace = true;
#endif
#endif
    atexit(do_shutdown);

#if LLVM_VERSION < 31
#ifdef CL_DEBUG
    //disable this for now, it leaks
    llvm::JITEmitDebugInfo = false;
//    llvm::JITEmitDebugInfo = true;
#else
    llvm::JITEmitDebugInfo = false;
#endif
    llvm::DwarfExceptionHandling = false;
#endif
#if LLVM_VERSION < 33
    llvm_start_multithreaded();
#else
    // This is now deprecated/useless: Multi-threading can only be enabled/disabled with the compile time define LLVM_ENABLE_THREADS in LLVM.
#endif

    // If we have a native target, initialize it to ensure it is linked in and
    // usable by the JIT.
#ifndef AC_APPLE_UNIVERSAL_BUILD
    InitializeNativeTarget();
#if LLVM_VERSION >= 36
    InitializeNativeTargetAsmPrinter();
    InitializeNativeTargetAsmParser();
#endif
#else
    InitializeAllTargets();
#endif

#if LLVM_VERSION < 35
    if (!llvm_is_multithreaded()) {
#else
    if (!LLVMIsMultithreaded()) {
#endif
	//TODO:cli_dbgmsg
	DEBUG(errs() << "WARNING: ClamAV JIT built w/o atomic builtins\n"
	      << "On x86 for best performance ClamAV should be built for i686, not i386!\n");
    }
    return 0;
}

// Called once when loading a new set of BC files
int cli_bytecode_init_jit(struct cli_all_bc *bcs, unsigned dconfmask)
{
    LLVMApiScopedLock scopedLock;
    bcs->engine = new(std::nothrow) cli_bcengine;
    if (!bcs->engine)
	return CL_EMEM;
    bcs->engine->EE = 0;
    bcs->engine->Listener = 0;
    return 0;
}

int cli_bytecode_done_jit(struct cli_all_bc *bcs, int partial)
{
    LLVMApiScopedLock scopedLock;
    if (bcs->engine) {
	if (bcs->engine->EE) {
	    if (bcs->engine->Listener)
		bcs->engine->EE->UnregisterJITEventListener(bcs->engine->Listener);
	    delete bcs->engine->EE;
	    bcs->engine->EE = 0;
	}
	delete bcs->engine->Listener;
	bcs->engine->Listener = 0;
	if (!partial) {
	    delete bcs->engine;
	    bcs->engine = 0;
	}
    }
    return 0;
}

void cli_bytecode_debug(int argc, char **argv)
{
  cl::ParseCommandLineOptions(argc, argv);
}

typedef struct lines {
    MemoryBuffer *buffer;
    std::vector<const char*> linev;
} linesTy;

static struct lineprinter {
    StringMap<linesTy*> files;
} LinePrinter;

void cli_bytecode_debug_printsrc(const struct cli_bc_ctx *ctx)
{
    if (!ctx->file || !ctx->directory || !ctx->line) {
	errs() << (ctx->directory ? "d":"null") << ":" << (ctx->file ? "f" : "null")<< ":" << ctx->line << "\n";
	return;
    }
    // acquire a mutex here
    sys::Mutex mtx(false);
    sys::SmartScopedLock<false> lock(mtx);

    std::string path = std::string(ctx->directory) + "/" + std::string(ctx->file);
    StringMap<linesTy*>::iterator I = LinePrinter.files.find(path);
    linesTy *lines;
    if (I == LinePrinter.files.end()) {
	lines = new linesTy;
	std::string ErrorMessage;
#if LLVM_VERSION < 29
	lines->buffer = MemoryBuffer::getFile(path, &ErrorMessage);
#elif LLVM_VERSION < 35
	OwningPtr<MemoryBuffer> File;
	error_code ec = MemoryBuffer::getFile(path, File);
	if (ec) {
	    ErrorMessage = ec.message();
	    lines->buffer = 0;
	} else
	    lines->buffer = File.take();
#else
	ErrorOr<std::unique_ptr<MemoryBuffer>> FileOrErr = MemoryBuffer::getFile(path);
	if (!FileOrErr) {
		// TODO: How to handle ErrorMessage?
		lines->buffer = 0;
	}
	else {
		lines->buffer = FileOrErr.get().release();
	}
#endif
	if (!lines->buffer) {
	    errs() << "Unable to open file '" << path << "'\n";
	    delete lines;
	    return ;
	}
	LinePrinter.files[path] = lines;
    } else {
	lines = I->getValue();
    }
    while (lines->linev.size() <= ctx->line+1) {
	const char *p;
	if (lines->linev.empty()) {
	    p = lines->buffer->getBufferStart();
	    lines->linev.push_back(p);
	} else {
	    p = lines->linev.back();
	    if (p == lines->buffer->getBufferEnd())
		break;
	    p = strchr(p, '\n');
	    if (!p) {
		p = lines->buffer->getBufferEnd();
		lines->linev.push_back(p);
	    } else
		lines->linev.push_back(p+1);
	}
    }
    if (ctx->line >= lines->linev.size()) {
	errs() << "Line number " << ctx->line << "out of file\n";
	return;
    }
    assert(ctx->line < lines->linev.size());

#if LLVM_VERSION < 28
    int line = (int)ctx->line ? (int)ctx->line : -1;
    int col = (int)ctx->col ? (int)ctx->col : -1;
    //TODO: print this ourselves, instead of using SMDiagnostic
    SMDiagnostic diag(ctx->file, line, col,
		 "", std::string(lines->linev[ctx->line-1], lines->linev[ctx->line]-1));
    diag.Print("[trace]", errs());
#endif
}

int have_clamjit=1;
void cli_bytecode_printversion()
{
  cl::PrintVersionMessage();
}

void cli_printcxxver()
{
    /* Try to print information about some commonly used compilers */
#ifdef __GNUC__
    printf("GNU C++: %s (%u.%u.%u)\n", __VERSION__, __GNUC__, __GNUC_MINOR__,
	   __GNUC_PATCHLEVEL__);
#endif
#ifdef __INTEL_COMPILER
    printf("Intel Compiler C++ %u\n", __INTEL_COMPILER);
#endif
#ifdef _MSC_VER
    printf("Microsoft Visual C++ %u\n", _MSC_VER);
#endif
}

namespace ClamBCModule {
void stop(const char *msg, llvm::Function* F, llvm::Instruction* I)
{
    if (F && F->hasName()) {
#if LLVM_VERSION < 31
	cli_warnmsg("[Bytecode JIT] in function %s: %s", F->getNameStr().c_str(), msg);
#else
	cli_warnmsg("[Bytecode JIT] in function %s: %s", F->getName().str().c_str(), msg);
#endif
    } else {
	cli_warnmsg("[Bytecode JIT] %s", msg);
    }
}
}

#if LLVM_VERSION >= 29
#if LLVM_VERSION < 36
static Value *findDbgGlobalDeclare(GlobalVariable *V) {
#else
static Metadata *findDbgGlobalDeclare(GlobalVariable *V) {
#endif
  const Module *M = V->getParent();
  NamedMDNode *NMD = M->getNamedMetadata("llvm.dbg.gv");
  if (!NMD)
    return 0;

  for (unsigned i = 0, e = NMD->getNumOperands(); i != e; ++i) {
    DIDescriptor DIG(cast<MDNode>(NMD->getOperand(i)));
    if (!DIG.isGlobalVariable())
      continue;
    if (DIGlobalVariable(DIG).getGlobal() == V)
      return DIG;
  }
  return 0;
}

/// Find the debug info descriptor corresponding to this function.
#if LLVM_VERSION < 36
static Value *findDbgSubprogramDeclare(Function *V) {
#else
static Metadata *findDbgSubprogramDeclare(Function *V) {
#endif
  const Module *M = V->getParent();
  NamedMDNode *NMD = M->getNamedMetadata("llvm.dbg.sp");
  if (!NMD)
    return 0;

  for (unsigned i = 0, e = NMD->getNumOperands(); i != e; ++i) {
    DIDescriptor DIG(cast<MDNode>(NMD->getOperand(i)));
    if (!DIG.isSubprogram())
      continue;
    if (DISubprogram(DIG).getFunction() == V)
      return DIG;
  }
  return 0;
}

/// Finds the llvm.dbg.declare intrinsic corresponding to this value if any.
/// It looks through pointer casts too.
static const DbgDeclareInst *findDbgDeclare(const Value *V) {
  V = V->stripPointerCasts();

  if (!isa<Instruction>(V) && !isa<Argument>(V))
    return 0;

  const Function *F = NULL;
  if (const Instruction *I = dyn_cast<Instruction>(V))
    F = I->getParent()->getParent();
  else if (const Argument *A = dyn_cast<Argument>(V))
    F = A->getParent();

  for (Function::const_iterator FI = F->begin(), FE = F->end(); FI != FE; ++FI)
    for (BasicBlock::const_iterator BI = (*FI).begin(), BE = (*FI).end();
         BI != BE; ++BI)
      if (const DbgDeclareInst *DDI = dyn_cast<DbgDeclareInst>(BI))
        if (DDI->getAddress() == V)
          return DDI;

  return 0;
}
static bool getLocationInfo(const Value *V, std::string &DisplayName,
                            std::string &Type, unsigned &LineNo,
                            std::string &File, std::string &Dir) {
#if LLVM_VERSION < 33
  DICompileUnit Unit;
#else
  StringRef G;
  StringRef H;
#endif
#if LLVM_VERSION < 35
  DIType TypeD;
#endif
  StringRef T;

  if (GlobalVariable *GV = dyn_cast<GlobalVariable>(const_cast<Value*>(V))) {
#if LLVM_VERSION < 36
    Value *DIGV = findDbgGlobalDeclare(GV);
#else
    Metadata *DIGV = findDbgGlobalDeclare(GV);
#endif
    if (!DIGV) return false;
    DIGlobalVariable Var(cast<MDNode>(DIGV));

    StringRef D = Var.getDisplayName();
    if (!D.empty())
      DisplayName = D;
    LineNo = Var.getLineNumber();
#if LLVM_VERSION < 33
    Unit = Var.getCompileUnit();
#else
    G = Var.getFilename();
    H = Var.getDirectory();
#endif
#if LLVM_VERSION < 35
    TypeD = Var.getType();
#else
    T = Var.getType().getName();
#endif
  } else if (Function *F = dyn_cast<Function>(const_cast<Value*>(V))){
#if LLVM_VERSION < 36
    Value *DIF = findDbgSubprogramDeclare(F);
#else
    Metadata *DIF = findDbgSubprogramDeclare(F);
#endif
    if (!DIF) return false;
    DISubprogram Var(cast<MDNode>(DIF));

    StringRef D = Var.getDisplayName();
    if (!D.empty())
      DisplayName = D;
    LineNo = Var.getLineNumber();
#if LLVM_VERSION < 33
    Unit = Var.getCompileUnit();
#else
    G = Var.getFilename();
    H = Var.getDirectory();
#endif
#if LLVM_VERSION < 35
    TypeD = Var.getType();
#else
    T = Var.getType().getName();
#endif
  } else {
    const DbgDeclareInst *DDI = findDbgDeclare(V);
    if (!DDI) return false;
    DIVariable Var(cast<MDNode>(DDI->getVariable()));

    StringRef D = Var.getName();
    if (!D.empty())
      DisplayName = D;
    LineNo = Var.getLineNumber();
#if LLVM_VERSION < 33
    Unit = Var.getCompileUnit();
#else
    // getFilename and getDirectory are not defined
    G = StringRef();
    H = StringRef();
#endif
#if LLVM_VERSION < 35
    TypeD = Var.getType();
#else
    T = Var.getType().getName();
#endif
  }

#if LLVM_VERSION < 35
  T = TypeD.getName();
#endif
  if (!T.empty())
    Type = T;
#if LLVM_VERSION < 33
  StringRef G = Unit.getFilename();
  StringRef H = Unit.getDirectory();
#endif
  if (!G.empty())
    File = G;
  if (!H.empty())
    Dir = H;
  return true;
}
#endif

void printValue(llvm::Value *V, bool a, bool b) {
    std::string DisplayName;
    std::string Type;
    unsigned Line;
    std::string File;
    std::string Dir;
    if (!getLocationInfo(V, DisplayName, Type, Line, File, Dir)) {
	errs() << *V << "\n";
	return;
    }
    errs() << "'" << DisplayName << "' (" << File << ":" << Line << ")";
}

void printLocation(llvm::Instruction *I, bool a, bool b) {
    if (MDNode *N = I->getMetadata("dbg")) {
	DILocation Loc(N);
	errs() << Loc.getFilename() << ":" << Loc.getLineNumber();
	if (unsigned Col = Loc.getColumnNumber()) {
  	    errs() << ":" << Col;
  	}
  	errs() << ": ";
  	return;
    }
    errs() << *I << ":\n";
}
