/*
  Copyright (C) 2002-2015 Jeroen Frijters

  This software is provided 'as-is', without any express or implied
  warranty.  In no event will the authors be held liable for any damages
  arising from the use of this software.

  Permission is granted to anyone to use this software for any purpose,
  including commercial applications, and to alter it and redistribute it
  freely, subject to the following restrictions:

  1. The origin of this software must not be misrepresented; you must not
     claim that you wrote the original software. If you use this software
     in a product, an acknowledgment in the product documentation would be
     appreciated but is not required.
  2. Altered source versions must be plainly marked as such, and must not be
     misrepresented as being the original software.
  3. This notice may not be removed or altered from any source distribution.

  Jeroen Frijters
  jeroen@frijters.net
  
*/
using System;
using System.Reflection;
using System.Diagnostics;
using System.Threading;
using IKVM.Attributes;
using IKVM.Internal;
using System.Runtime.InteropServices;

namespace IKVM.Runtime
{
	static class GhostTag
	{
		private static volatile PassiveWeakDictionary<object, TypeWrapper> dict;

		internal static void SetTag(object obj, RuntimeTypeHandle typeHandle)
		{
			SetTag(obj, ClassLoaderWrapper.GetWrapperFromType(Type.GetTypeFromHandle(typeHandle)));
		}

		internal static void SetTag(object obj, TypeWrapper wrapper)
		{
			if(dict == null)
			{
				PassiveWeakDictionary<object, TypeWrapper> newDict = new PassiveWeakDictionary<object, TypeWrapper>();
#pragma warning disable 0420 // don't whine about CompareExchange not respecting 'volatile'
				if(Interlocked.CompareExchange(ref dict, newDict, null) != null)
#pragma warning restore
				{
					newDict.Dispose();
				}
			}
			dict.Add(obj, wrapper);
		}

		internal static TypeWrapper GetTag(object obj)
		{
			if(dict != null)
			{
				TypeWrapper tw;
				dict.TryGetValue(obj, out tw);
				return tw;
			}
			return null;
		}

		// this method is called from <GhostType>.IsInstanceArray()
		internal static bool IsGhostArrayInstance(object obj, RuntimeTypeHandle typeHandle, int rank)
		{
			TypeWrapper tw1 = GhostTag.GetTag(obj);
			if(tw1 != null)
			{
				TypeWrapper tw2 = ClassLoaderWrapper.GetWrapperFromType(Type.GetTypeFromHandle(typeHandle)).MakeArrayType(rank);
				return tw1.IsAssignableTo(tw2);
			}
			return false;
		}

		// this method is called from <GhostType>.CastArray()
		[HideFromJava]
		internal static void ThrowClassCastException(object obj, RuntimeTypeHandle typeHandle, int rank)
		{
#if !FIRST_PASS
			System.Text.StringBuilder sb = new System.Text.StringBuilder();
			sb.Append(ikvm.runtime.Util.getClassFromObject(obj).getName()).Append(" cannot be cast to ")
				.Append('[', rank).Append('L').Append(ikvm.runtime.Util.getClassFromTypeHandle(typeHandle).getName()).Append(';');
			throw new java.lang.ClassCastException(sb.ToString());
#endif
		}
	}

	public static class ByteCodeHelper
	{
		[DebuggerStepThroughAttribute]
		public static object multianewarray(RuntimeTypeHandle typeHandle, int[] lengths)
		{
			for(int i = 0; i < lengths.Length; i++)
			{
				if(lengths[i] < 0)
				{
#if !FIRST_PASS
					throw new java.lang.NegativeArraySizeException();
#endif
				}
			}
			return MultianewarrayHelper(Type.GetTypeFromHandle(typeHandle).GetElementType(), lengths, 0);
		}

		private static object MultianewarrayHelper(Type elemType, int[] lengths, int index)
		{
			object o = Array.CreateInstance(elemType, lengths[index++]);
			if(index < lengths.Length)
			{
				elemType = elemType.GetElementType();
				object[] a = (object[])o;
				for(int i = 0; i < a.Length; i++)
				{
					a[i] = MultianewarrayHelper(elemType, lengths, index);
				}
			}
			return o;
		}

		[DebuggerStepThroughAttribute]
		public static object multianewarray_ghost(RuntimeTypeHandle typeHandle, int[] lengths)
		{
			Type type = Type.GetTypeFromHandle(typeHandle);
			int rank = 0;
			while(ReflectUtil.IsVector(type))
			{
				rank++;
				type = type.GetElementType();
			}
			object obj = multianewarray(ArrayTypeWrapper.MakeArrayType(typeof(object), rank).TypeHandle, lengths);
			GhostTag.SetTag(obj, typeHandle);
			return obj;
		}

		[DebuggerStepThroughAttribute]
		public static T[] anewarray_ghost<T>(int length, RuntimeTypeHandle typeHandle)
		{
			T[] obj = new T[length];
			GhostTag.SetTag(obj, typeHandle);
			return obj;
		}

		[DebuggerStepThroughAttribute]
		public static object DynamicMultianewarray(int[] lengths, java.lang.Class clazz)
		{
#if FIRST_PASS
			return null;
#else
			Profiler.Count("DynamicMultianewarray");
			TypeWrapper wrapper = TypeWrapper.FromClass(clazz);
			object obj = multianewarray(wrapper.TypeAsArrayType.TypeHandle, lengths);
			if (wrapper.IsGhostArray)
			{
				GhostTag.SetTag(obj, wrapper);
			}
			return obj;
#endif
		}

		[DebuggerStepThroughAttribute]
		public static object DynamicNewarray(int length, java.lang.Class clazz)
		{
#if FIRST_PASS
			return null;
#else
			Profiler.Count("DynamicNewarray");
			if(length < 0)
			{
				throw new java.lang.NegativeArraySizeException();
			}
			TypeWrapper wrapper = TypeWrapper.FromClass(clazz);
			Array obj = Array.CreateInstance(wrapper.TypeAsArrayType, length);
			if (wrapper.IsGhost || wrapper.IsGhostArray)
			{
				GhostTag.SetTag(obj, wrapper.MakeArrayType(1));
			}
			return obj;
#endif
		}

		[DebuggerStepThroughAttribute]
		public static void DynamicAastore(object arrayref, int index, object val)
		{
#if !FIRST_PASS
			Profiler.Count("DynamicAastore");
			((Array)arrayref).SetValue(val, index);
#endif
		}

		[DebuggerStepThroughAttribute]
		public static object DynamicAaload(object arrayref, int index)
		{
#if FIRST_PASS
			return null;
#else
			Profiler.Count("DynamicAaload");
			return ((Array)arrayref).GetValue(index);
#endif
		}

		// the sole purpose of this method is to check whether the clazz can be instantiated (but not to actually do it)
		[DebuggerStepThroughAttribute]
		public static void DynamicNewCheckOnly(java.lang.Class clazz)
		{
#if !FIRST_PASS
			Profiler.Count("DynamicNewCheckOnly");
			TypeWrapper wrapper = TypeWrapper.FromClass(clazz);
			if(wrapper.IsAbstract)
			{
				throw new java.lang.InstantiationError(wrapper.Name);
			}
			wrapper.RunClassInit();
#endif
		}

		private static TypeWrapper LoadTypeWrapper(string clazz, ikvm.@internal.CallerID callerId)
		{
#if FIRST_PASS
			return null;
#else
			try
			{
				TypeWrapper context = TypeWrapper.FromClass(callerId.getCallerClass());
				TypeWrapper wrapper = ClassLoaderWrapper.FromCallerID(callerId).LoadClassByDottedName(clazz);
				java.lang.ClassLoader loader = callerId.getCallerClassLoader();
				if(loader != null)
				{
					loader.checkPackageAccess(wrapper.ClassObject, callerId.getCallerClass().pd);
				}
				if(!wrapper.IsAccessibleFrom(context))
				{
					throw new java.lang.IllegalAccessError("Try to access class " + wrapper.Name + " from class " + context.Name);
				}
				wrapper.Finish();
				return wrapper;
			}
			catch(RetargetableJavaException x)
			{
				throw x.ToJava();
			}
#endif
		}

		[DebuggerStepThroughAttribute]
		public static java.lang.Class DynamicClassLiteral(string clazz, ikvm.@internal.CallerID callerId)
		{
#if FIRST_PASS
			return null;
#else
			Profiler.Count("DynamicClassLiteral");
			return LoadTypeWrapper(clazz, callerId).ClassObject;
#endif
		}

		[DebuggerStepThroughAttribute]
		public static object DynamicCast(object obj, java.lang.Class clazz)
		{
#if FIRST_PASS
			return null;
#else
			Debug.Assert(obj != null);
			Profiler.Count("DynamicCast");
			if (!DynamicInstanceOf(obj, clazz))
			{
				throw new java.lang.ClassCastException(NativeCode.ikvm.runtime.Util.GetTypeWrapperFromObject(obj).Name + " cannot be cast to " + clazz.getName());
			}
			return obj;
#endif
		}

		[DebuggerStepThroughAttribute]
		public static bool DynamicInstanceOf(object obj, java.lang.Class clazz)
		{
#if FIRST_PASS
			return false;
#else
			Debug.Assert(obj != null);
			Profiler.Count("DynamicInstanceOf");
			TypeWrapper tw = TypeWrapper.FromClass(clazz);
			// we have to mimick the bytecode behavior, which allows these .NET-isms to show through
			if (tw.TypeAsBaseType == typeof(Array))
			{
				return obj is Array;
			}
			if (tw.TypeAsBaseType == typeof(string))
			{
				return obj is string;
			}
			if (tw.TypeAsBaseType == typeof(IComparable))
			{
				return obj is IComparable;
			}
			return tw.IsInstance(obj);
#endif
		}

		[DebuggerStepThrough]
		public static java.lang.invoke.MethodType DynamicLoadMethodType(ref java.lang.invoke.MethodType cache, string sig, ikvm.@internal.CallerID callerID)
		{
			if (cache == null)
			{
				DynamicLoadMethodTypeImpl(ref cache, sig, callerID);
			}
			return cache;
		}

		private static void DynamicLoadMethodTypeImpl(ref java.lang.invoke.MethodType cache, string sig, ikvm.@internal.CallerID callerID)
		{
#if !FIRST_PASS
			try
			{
				ClassLoaderWrapper loader = ClassLoaderWrapper.FromCallerID(callerID);
				TypeWrapper[] args = loader.ArgTypeWrapperListFromSig(sig, LoadMode.LoadOrThrow);
				java.lang.Class[] ptypes = new java.lang.Class[args.Length];
				for (int i = 0; i < ptypes.Length; i++)
				{
					ptypes[i] = args[i].ClassObject;
				}
				Interlocked.CompareExchange(ref cache, java.lang.invoke.MethodType.methodType(loader.RetTypeWrapperFromSig(sig, LoadMode.LoadOrThrow).ClassObject, ptypes), null);
			}
			catch (RetargetableJavaException x)
			{
				throw x.ToJava();
			}
#endif
		}

		[DebuggerStepThrough]
		public static java.lang.invoke.MethodHandle DynamicLoadMethodHandle(ref java.lang.invoke.MethodHandle cache, int kind, string clazz, string name, string sig, ikvm.@internal.CallerID callerID)
		{
			if (cache == null)
			{
				Interlocked.CompareExchange(ref cache, DynamicLoadMethodHandleImpl(kind, clazz, name, sig, callerID), null);
			}
			return cache;
		}

		private static java.lang.invoke.MethodHandle DynamicLoadMethodHandleImpl(int kind, string clazz, string name, string sig, ikvm.@internal.CallerID callerID)
		{
#if FIRST_PASS
			return null;
#else
			java.lang.Class refc = LoadTypeWrapper(clazz, callerID).ClassObject;
			try
			{
				switch ((ClassFile.RefKind)kind)
				{
					case ClassFile.RefKind.getStatic:
					case ClassFile.RefKind.putStatic:
					case ClassFile.RefKind.getField:
					case ClassFile.RefKind.putField:
						java.lang.Class type = ClassLoaderWrapper.FromCallerID(callerID).FieldTypeWrapperFromSig(sig, LoadMode.LoadOrThrow).ClassObject;
						return java.lang.invoke.MethodHandleNatives.linkMethodHandleConstant(callerID.getCallerClass(), kind, refc, name, type);
					default:
						java.lang.invoke.MethodType mt = null;
						DynamicLoadMethodType(ref mt, sig, callerID);
						// HACK linkMethodHandleConstant is broken for MethodHandle.invoke[Exact]
						if (kind == (int)ClassFile.RefKind.invokeVirtual && refc == CoreClasses.java.lang.invoke.MethodHandle.Wrapper.ClassObject)
						{
							switch (name)
							{
								case "invokeExact":
									return java.lang.invoke.MethodHandles.exactInvoker(mt);
								case "invoke":
									return java.lang.invoke.MethodHandles.invoker(mt);
							}
						}
						return java.lang.invoke.MethodHandleNatives.linkMethodHandleConstant(callerID.getCallerClass(), kind, refc, name, mt);
				}
			}
			catch (RetargetableJavaException x)
			{
				throw x.ToJava();
			}
#endif
		}

		[DebuggerStepThrough]
		public static T DynamicBinderMemberLookup<T>(int kind, string clazz, string name, string sig, ikvm.@internal.CallerID callerID)
			where T : class /* delegate */
		{
#if FIRST_PASS
			return null;
#else
			try
			{
				java.lang.invoke.MethodHandle mh = DynamicLoadMethodHandleImpl(kind, clazz, name, sig, callerID);
				return GetDelegateForInvokeExact<T>(java.lang.invoke.MethodHandles.explicitCastArguments(mh, MethodHandleUtil.GetDelegateMethodType(typeof(T))));
			}
			catch (java.lang.IncompatibleClassChangeError x)
			{
				if (x.getCause() is java.lang.NoSuchMethodException)
				{
					throw new java.lang.NoSuchMethodError(x.getCause().Message);
				}
				if (x.getCause() is java.lang.NoSuchFieldException)
				{
					throw new java.lang.NoSuchFieldError(x.getCause().Message);
				}
				if (x.getCause() is java.lang.IllegalAccessException)
				{
					throw new java.lang.IllegalAccessError(x.getCause().Message);
				}
				throw;
			}
#endif
		}

		[DebuggerStepThrough]
		public static Delegate DynamicCreateDelegate(object obj, Type delegateType, string name, string sig)
		{
#if FIRST_PASS
			return null;
#else
			TypeWrapper tw = TypeWrapper.FromClass(ikvm.runtime.Util.getClassFromObject(obj));
			MethodWrapper mw = tw.GetMethodWrapper(name, sig, true);
			if (mw == null || mw.IsStatic || !mw.IsPublic)
			{
#if NO_REF_EMIT
				java.lang.invoke.MethodType methodType = MethodHandleUtil.GetDelegateMethodType(delegateType);
				if (methodType.parameterCount() > MethodHandleUtil.MaxArity)
				{
					throw new NotImplementedException();
				}
				java.lang.invoke.MethodHandle exception = java.lang.invoke.MethodHandles.publicLookup()
					.findConstructor(mw == null || mw.IsStatic ? typeof(java.lang.AbstractMethodError) : typeof(java.lang.IllegalAccessError),
						java.lang.invoke.MethodType.methodType(typeof(void), typeof(string)))
					.bindTo(tw.Name + ".Invoke" + sig);
				return Delegate.CreateDelegate(delegateType,
						java.lang.invoke.MethodHandles.dropArguments(
							java.lang.invoke.MethodHandles.foldArguments(java.lang.invoke.MethodHandles.throwException(methodType.returnType(), exception.type().returnType()), exception),
							0, methodType.parameterArray()).vmtarget, "Invoke");
#else
				MethodInfo invoke = delegateType.GetMethod("Invoke");
				ParameterInfo[] parameters = invoke.GetParameters();
				Type[] parameterTypes = new Type[parameters.Length + 1];
				parameterTypes[0] = typeof(object);
				for (int i = 0; i < parameters.Length; i++)
				{
					parameterTypes[i + 1] = parameters[i].ParameterType;
				}
				System.Reflection.Emit.DynamicMethod dm = new System.Reflection.Emit.DynamicMethod("Invoke", invoke.ReturnType, parameterTypes);
				CodeEmitter ilgen = CodeEmitter.Create(dm);
				ilgen.Emit(System.Reflection.Emit.OpCodes.Ldstr, tw.Name + ".Invoke" + sig);
				ClassLoaderWrapper.GetBootstrapClassLoader()
					.LoadClassByDottedName(mw == null || mw.IsStatic ? "java.lang.AbstractMethodError" : "java.lang.IllegalAccessError")
					.GetMethodWrapper("<init>", "(Ljava.lang.String;)V", false)
					.EmitNewobj(ilgen);
				ilgen.Emit(System.Reflection.Emit.OpCodes.Throw);
				ilgen.DoEmit();
				return dm.CreateDelegate(delegateType, obj);
#endif
			}
			else
			{
				mw.ResolveMethod();
				return Delegate.CreateDelegate(delegateType, obj, (MethodInfo)mw.GetMethod());
			}
#endif
		}

		[DebuggerStepThrough]
		public static ikvm.@internal.CallerID DynamicCallerID(object capability)
		{
			return ((DynamicCallerIDProvider)capability).GetCallerID();
		}

		[DebuggerStepThrough]
		public static java.lang.invoke.MethodHandle DynamicEraseInvokeExact(java.lang.invoke.MethodHandle mh, java.lang.invoke.MethodType expected, java.lang.invoke.MethodType target)
		{
#if FIRST_PASS
			return null;
#else
			if (mh.type() != expected)
			{
				throw new java.lang.invoke.WrongMethodTypeException();
			}
			return java.lang.invoke.MethodHandles.explicitCastArguments(mh, target);
#endif
		}

		[DebuggerStepThroughAttribute]
		public static int f2i(float f)
		{
			if (f > int.MinValue && f < int.MaxValue)
			{
				return (int)f;
			}
			if (f <= int.MinValue)
			{
				return int.MinValue;
			}
			if (f >= int.MaxValue)
			{
				return int.MaxValue;
			}
			return 0;
		}

		[DebuggerStepThroughAttribute]
		public static long f2l(float f)
		{
			if (f > long.MinValue && f < long.MaxValue)
			{
				return (long)f;
			}
			if (f <= long.MinValue)
			{
				return long.MinValue;
			}
			if (f >= long.MaxValue)
			{
				return long.MaxValue;
			}
			return 0;
		}

		[DebuggerStepThroughAttribute]
		public static int d2i(double d)
		{
			if (d > int.MinValue && d < int.MaxValue)
			{
				return (int)d;
			}
			if (d <= int.MinValue)
			{
				return int.MinValue;
			}
			if (d >= int.MaxValue)
			{
				return int.MaxValue;
			}
			return 0;
		}

		[DebuggerStepThroughAttribute]
		public static long d2l(double d)
		{
			if (d > long.MinValue && d < long.MaxValue)
			{
				return (long)d;
			}
			if (d <= long.MinValue)
			{
				return long.MinValue;
			}
			if (d >= long.MaxValue)
			{
				return long.MaxValue;
			}
			return 0;
		}

		// This is used by static JNI and synchronized methods that need a class object
		[DebuggerStepThroughAttribute]
		public static object GetClassFromTypeHandle(RuntimeTypeHandle typeHandle)
		{
			return NativeCode.ikvm.runtime.Util.getClassFromTypeHandle(typeHandle);
		}

		[DebuggerStepThroughAttribute]
		public static void arraycopy(object src, int srcStart, object dest, int destStart, int len)
		{
#if !FIRST_PASS
			// If the two arrays are the same, we can use the fast path, but we're also required to do so,
			// to get the required memmove semantics.
			if(src == dest)
			{
				try
				{
					arraycopy_fast((Array)src, srcStart, (Array)dest, destStart, len);
					return;
				}
				catch(InvalidCastException)
				{
					throw new java.lang.ArrayStoreException();
				}
			}
			else if(src == null || dest == null)
			{
				throw new java.lang.NullPointerException();
			}
			else if(len < 0)
			{
				throw new java.lang.ArrayIndexOutOfBoundsException();
			}
			else
			{
				object[] src1 = src as object[];
				object[] dst1 = dest as object[];
				if(src1 != null && dst1 != null)
				{
					// for small copies, don't bother comparing the types as this is relatively expensive
					if(len > 50 && src.GetType() == dest.GetType())
					{
						arraycopy_fast(src1, srcStart, dst1, destStart, len);
						return;
					}
					else
					{
						for(; len > 0; len--)
						{
							// NOTE we don't need to catch ArrayTypeMismatchException & IndexOutOfRangeException, because
							// they automatically get converted to the Java equivalents anyway.
							dst1[destStart++] = src1[srcStart++];
						}
						return;
					}
				}
				else if(src.GetType() != dest.GetType() &&
						(IsPrimitiveArrayType(src.GetType()) || IsPrimitiveArrayType(dest.GetType())))
				{
					// we don't want to allow copying a primitive into an object array!
					throw new java.lang.ArrayStoreException();
				}
				else
				{
					try
					{
						arraycopy_fast((Array)src, srcStart, (Array)dest, destStart, len);
						return;
					}
					catch(InvalidCastException)
					{
						throw new java.lang.ArrayStoreException();
					}
				}
			}
#endif // !FIRST_PASS
		}

		private static bool IsPrimitiveArrayType(Type type)
		{
			return type.IsArray && ClassLoaderWrapper.GetWrapperFromType(type.GetElementType()).IsPrimitive;
		}
		
		[DebuggerStepThroughAttribute]
		public static void arraycopy_fast(Array src, int srcStart, Array dest, int destStart, int len)
		{
#if !FIRST_PASS
			try 
			{
				Array.Copy(src, srcStart, dest, destStart, len);
			}
			catch(ArgumentNullException)
			{
				throw new java.lang.NullPointerException();
			}
			catch(ArgumentException) 
			{
				throw new java.lang.ArrayIndexOutOfBoundsException();
			}
#endif // !FIRST_PASS
		}

		[DebuggerStepThroughAttribute]
		public static void arraycopy_primitive_8(Array src, int srcStart, Array dest, int destStart, int len)
		{
#if !FIRST_PASS
			try 
			{
				checked
				{
					Buffer.BlockCopy(src, srcStart * 8, dest, destStart * 8, len * 8);
					return;
				}
			}
			catch(ArgumentNullException)
			{
				throw new java.lang.NullPointerException();
			}
			catch(OverflowException)
			{
				throw new java.lang.ArrayIndexOutOfBoundsException();
			}
			catch(ArgumentException) 
			{
				throw new java.lang.ArrayIndexOutOfBoundsException();
			}
#endif // !FIRST_PASS
		}

		[DebuggerStepThroughAttribute]
		public static void arraycopy_primitive_4(Array src, int srcStart, Array dest, int destStart, int len)
		{
#if !FIRST_PASS
			try 
			{
				checked
				{
					Buffer.BlockCopy(src, srcStart * 4, dest, destStart * 4, len * 4);
					return;
				}
			}
			catch(ArgumentNullException)
			{
				throw new java.lang.NullPointerException();
			}
			catch(OverflowException)
			{
				throw new java.lang.ArrayIndexOutOfBoundsException();
			}
			catch(ArgumentException) 
			{
				throw new java.lang.ArrayIndexOutOfBoundsException();
			}
#endif // !FIRST_PASS
		}

		[DebuggerStepThroughAttribute]
		public static void arraycopy_primitive_2(Array src, int srcStart, Array dest, int destStart, int len)
		{
#if !FIRST_PASS
			try 
			{
				checked
				{
					Buffer.BlockCopy(src, srcStart * 2, dest, destStart * 2, len * 2);
					return;
				}
			}
			catch(ArgumentNullException)
			{
				throw new java.lang.NullPointerException();
			}
			catch(OverflowException)
			{
				throw new java.lang.ArrayIndexOutOfBoundsException();
			}
			catch(ArgumentException) 
			{
				throw new java.lang.ArrayIndexOutOfBoundsException();
			}
#endif // !FIRST_PASS
		}

		[DebuggerStepThroughAttribute]
		public static void arraycopy_primitive_1(Array src, int srcStart, Array dest, int destStart, int len)
		{
#if !FIRST_PASS
			try 
			{
				Buffer.BlockCopy(src, srcStart, dest, destStart, len);
				return;
			}
			catch(ArgumentNullException)
			{
				throw new java.lang.NullPointerException();
			}
			catch(OverflowException)
			{
				throw new java.lang.ArrayIndexOutOfBoundsException();
			}
			catch(ArgumentException) 
			{
				throw new java.lang.ArrayIndexOutOfBoundsException();
			}
#endif // !FIRST_PASS
		}

		[HideFromJava]
		public static void VerboseCastFailure(RuntimeTypeHandle typeHandle, object obj)
		{
#if !FIRST_PASS
			Type t1 = obj.GetType();
			Type t2 = Type.GetTypeFromHandle(typeHandle);
			string msg;
			if(t1.Assembly.FullName == t2.Assembly.FullName && t1.Assembly.Location != t2.Assembly.Location)
			{
				string l1 = t1.Assembly.Location;
				string l2 = t2.Assembly.Location;
				if(l1 == "")
				{
					l1 = "unknown location";
				}
				if(l2 == "")
				{
					l2 = "unknown location";
				}
				msg = String.Format("Object of type \"{0}\" loaded from {1} cannot be cast to \"{2}\" loaded from {3}", t1.AssemblyQualifiedName, l1, t2.AssemblyQualifiedName, l2);
			}
			else
			{
				msg = String.Format("Object of type \"{0}\" cannot be cast to \"{1}\"", t1.AssemblyQualifiedName, t2.AssemblyQualifiedName);
			}
			throw new java.lang.ClassCastException(msg);
#endif // !FIRST_PASS
		}

		public static bool SkipFinalizer()
		{
#if FIRST_PASS
			return false;
#else
			return Environment.HasShutdownStarted && !java.lang.Shutdown.runFinalizersOnExit;
#endif
		}

		public static long VolatileRead(ref long v)
		{
#if NO_REF_EMIT && !FIRST_PASS
			lock (VolatileLongDoubleFieldWrapper.lockObject)
			{
				return v;
			}
#else
			return Interlocked.Read(ref v);
#endif
		}

		public static void VolatileWrite(ref long v, long newValue)
		{
#if NO_REF_EMIT && !FIRST_PASS
			lock (VolatileLongDoubleFieldWrapper.lockObject)
			{
				v = newValue;
			}
#else
			Interlocked.Exchange(ref v, newValue);
#endif
		}

		public static double VolatileRead(ref double v)
		{
#if NO_REF_EMIT && !FIRST_PASS
			lock (VolatileLongDoubleFieldWrapper.lockObject)
			{
				return v;
			}
#else
			return Interlocked.CompareExchange(ref v, 0.0, 0.0);
#endif
		}

		public static void VolatileWrite(ref double v, double newValue)
		{
#if NO_REF_EMIT && !FIRST_PASS
			lock (VolatileLongDoubleFieldWrapper.lockObject)
			{
				v = newValue;
			}
#else
			Interlocked.Exchange(ref v, newValue);
#endif
		}

		[System.Runtime.CompilerServices.MethodImpl(System.Runtime.CompilerServices.MethodImplOptions.NoInlining)]
		public static void InitializeModule(Module module)
		{
			Assembly asm = Assembly.GetCallingAssembly();
			if (module.Assembly != asm)
			{
				throw new ArgumentOutOfRangeException();
			}
			object classLoader = AssemblyClassLoader.FromAssembly(asm).GetJavaClassLoader();
			Action<Module> init = (Action<Module>)Delegate.CreateDelegate(typeof(Action<Module>), classLoader, "InitializeModule", false, false);
			if (init != null)
			{
				init(module);
			}
		}

		public static T GetDotNetEnumField<T>(string name)
#if !FIRST_PASS
			where T : java.lang.Enum
#endif
		{
#if FIRST_PASS
			return default(T);
#else
			try
			{
				return (T)java.lang.Enum.valueOf(ikvm.@internal.ClassLiteral<T>.Value, name);
			}
			catch (java.lang.IllegalArgumentException)
			{
				throw new java.lang.NoSuchFieldError(ikvm.@internal.ClassLiteral<T>.Value.getName() + "." + name);
			}
#endif
		}

		[Flags]
		public enum MapFlags
		{
			None = 0,
			NoRemapping = 1,
			Unused = 2,
		}

		[HideFromJava]
		public static T MapException<T>(Exception x, MapFlags mode) where T : Exception
		{
			return ExceptionHelper.MapException<T>(x, (mode & MapFlags.NoRemapping) == 0, (mode & MapFlags.Unused) != 0);
		}

		[HideFromJava]
		public static Exception DynamicMapException(Exception x, MapFlags mode, java.lang.Class exceptionClass)
		{
#if FIRST_PASS
			return null;
#else
			TypeWrapper exceptionTypeWrapper = TypeWrapper.FromClass(exceptionClass);
			mode &= ~MapFlags.NoRemapping;
			if (exceptionTypeWrapper.IsSubTypeOf(CoreClasses.cli.System.Exception.Wrapper))
			{
				mode |= MapFlags.NoRemapping;
			}
			Type exceptionType = exceptionTypeWrapper == CoreClasses.java.lang.Throwable.Wrapper ? typeof(System.Exception) : exceptionTypeWrapper.TypeAsBaseType;
			return (Exception)ByteCodeHelperMethods.mapException.MakeGenericMethod(exceptionType).Invoke(null, new object[] { x, mode });
#endif
		}

		public static T GetDelegateForInvokeExact<T>(global::java.lang.invoke.MethodHandle h)
			where T : class
		{
#if FIRST_PASS
			return null;
#else
			T del = h._invokeExactDelegate as T;
			if (del == null)
			{
				del = MethodHandleUtil.GetDelegateForInvokeExact<T>(h);
			}
			return del;
#endif
		}

		public static T GetDelegateForInvoke<T>(global::java.lang.invoke.MethodHandle h, java.lang.invoke.MethodType realType, ref InvokeCache<T> cache)
			where T : class
		{
#if FIRST_PASS
			return null;
#else
			T del;
			if (cache.Type == h.type() && (del = (h.isVarargsCollector() ? cache.varArg : cache.fixedArg)) != null)
			{
				return del;
			}
			del = h.form.vmentry.vmtarget as T;
			if (del == null)
			{
				global::java.lang.invoke.MethodHandle adapter = global::java.lang.invoke.MethodHandles.exactInvoker(h.type());
				if (h.isVarargsCollector())
				{
					adapter = adapter.asVarargsCollector(h.type().parameterType(h.type().parameterCount() - 1));
				}
				// if realType is set, the delegate contains erased unloadable types
				if (realType != null)
				{
					adapter = adapter.asType(realType.insertParameterTypes(0, ikvm.@internal.ClassLiteral<java.lang.invoke.MethodHandle>.Value)).asFixedArity();
				}
				adapter = adapter.asType(MethodHandleUtil.GetDelegateMethodType(typeof(T)));
				del = GetDelegateForInvokeExact<T>(adapter);
				if (cache.TrySetType(h.type()))
				{
					if (h.isVarargsCollector())
					{
						cache.varArg = del;
					}
					else
					{
						cache.fixedArg = del;
					}
				}
			}
			return del;
#endif
		}

		public static T GetDelegateForInvokeBasic<T>(java.lang.invoke.MethodHandle h)
			where T : class
		{
#if FIRST_PASS
			return null;
#else
			T del = h.form.vmentry.vmtarget as T;
			if (del == null)
			{
				del = MethodHandleUtil.GetVoidAdapter(h.form.vmentry) as T;
			}
			return del;
#endif
		}

		public static java.lang.invoke.MethodType LoadMethodType<T>()
			where T : class // Delegate
		{
#if FIRST_PASS
			return null;
#else
			return MethodHandleUtil.GetDelegateMethodType(typeof(T));
#endif
		}

		[HideFromJava]
		public static void LinkIndyCallSite<T>(ref IndyCallSite<T> site, java.lang.invoke.CallSite cs, Exception x)
			where T : class // Delegate
		{
#if !FIRST_PASS
			// when a CallSite is first constructed, it doesn't call MethodHandleNatives.setCallSiteTargetNormal(),
			// so we have to check if we need to initialize it here (i.e. attach an IndyCallSite<T> to it)
			if (cs != null)
			{
				if (cs.ics == null)
				{
					Java_java_lang_invoke_MethodHandleNatives.InitializeCallSite(cs);
				}
				lock (cs.ics)
				{
					cs.ics.SetTarget(cs.target);
				}
			}
			IndyCallSite<T> ics;
			if (x != null || cs == null || (ics = cs.ics as IndyCallSite<T>) == null)
			{
				x = MapException<Exception>(x ?? (cs == null
					? (Exception)new java.lang.ClassCastException("bootstrap method failed to produce a CallSite")
					: new java.lang.invoke.WrongMethodTypeException()), MapFlags.None);
				java.lang.invoke.MethodType type = LoadMethodType<T>();
				java.lang.invoke.MethodHandle exc = x is java.lang.BootstrapMethodError
					? java.lang.invoke.MethodHandles.constant(typeof(java.lang.BootstrapMethodError), x)
					: java.lang.invoke.MethodHandles.publicLookup().findConstructor(typeof(java.lang.BootstrapMethodError), java.lang.invoke.MethodType.methodType(typeof(void), typeof(string), typeof(Exception)))
						.bindTo("call site initialization exception").bindTo(x);
				ics = new IndyCallSite<T>();
				((IIndyCallSite)ics).SetTarget(
					java.lang.invoke.MethodHandles.dropArguments(
						java.lang.invoke.MethodHandles.foldArguments(
							java.lang.invoke.MethodHandles.throwException(type.returnType(), typeof(java.lang.BootstrapMethodError)),
								exc),
						0, type.parameterArray()));
			}
			IndyCallSite<T> curr = site;
			if (curr.IsBootstrap)
			{
				Interlocked.CompareExchange(ref site, ics, curr);
			}
#endif
		}

		[HideFromJava]
		public static void DynamicLinkIndyCallSite<T>(ref IndyCallSite<T> site, java.lang.invoke.CallSite cs, Exception x, string signature, ikvm.@internal.CallerID callerID)
			where T : class // Delegate
		{
#if !FIRST_PASS
			// when a CallSite is first constructed, it doesn't call MethodHandleNatives.setCallSiteTargetNormal(),
			// so we have to check if we need to initialize it here (i.e. attach an IndyCallSite<T> to it)
			if (cs != null)
			{
				if (cs.ics == null)
				{
					Java_java_lang_invoke_MethodHandleNatives.InitializeCallSite(cs);
				}
				lock (cs.ics)
				{
					cs.ics.SetTarget(cs.target);
				}
			}
			java.lang.invoke.MethodType typeCache = null;
			IndyCallSite<T> ics;
			if (x != null || cs == null || cs.type() != DynamicLoadMethodType(ref typeCache, signature, callerID))
			{
				x = MapException<Exception>(x ?? (cs == null
					? (Exception)new java.lang.ClassCastException("bootstrap method failed to produce a CallSite")
					: new java.lang.invoke.WrongMethodTypeException()), MapFlags.None);
				java.lang.invoke.MethodType type = LoadMethodType<T>();
				java.lang.invoke.MethodHandle exc = x is java.lang.BootstrapMethodError
					? java.lang.invoke.MethodHandles.constant(typeof(java.lang.BootstrapMethodError), x)
					: java.lang.invoke.MethodHandles.publicLookup().findConstructor(typeof(java.lang.BootstrapMethodError), java.lang.invoke.MethodType.methodType(typeof(void), typeof(string), typeof(Exception)))
						.bindTo("call site initialization exception").bindTo(x);
				ics = new IndyCallSite<T>();
				((IIndyCallSite)ics).SetTarget(
					java.lang.invoke.MethodHandles.dropArguments(
						java.lang.invoke.MethodHandles.foldArguments(
							java.lang.invoke.MethodHandles.throwException(type.returnType(), typeof(java.lang.BootstrapMethodError)),
								exc),
						0, type.parameterArray()));
			}
			else
			{
				ics = new IndyCallSite<T>();
				((IIndyCallSite)ics).SetTarget(cs.dynamicInvoker().asType(LoadMethodType<T>()));
			}
			IndyCallSite<T> curr = site;
			if (curr.IsBootstrap)
			{
				Interlocked.CompareExchange(ref site, ics, curr);
			}
#endif
		}
	}

	interface IIndyCallSite
	{
		void SetTarget(java.lang.invoke.MethodHandle mh);
	}

	public sealed class IndyCallSite<T>
		: IIndyCallSite
		where T : class // Delegate
	{
		internal readonly bool IsBootstrap;
		private volatile T target;

		internal IndyCallSite()
		{
		}

		internal IndyCallSite(T target, bool bootstrap)
		{
			this.IsBootstrap = bootstrap;
			this.target = target;
		}

		void IIndyCallSite.SetTarget(java.lang.invoke.MethodHandle mh)
		{
#if !FIRST_PASS
			target = ByteCodeHelper.GetDelegateForInvokeExact<T>(mh);
#endif
		}
		
		public static IndyCallSite<T> CreateBootstrap(T bootstrap)
		{
			return new IndyCallSite<T>(bootstrap, true);
		}

		public T GetTarget()
		{
			return target;
		}
	}

	public struct InvokeCache<T>
		where T : class
	{
#if CLASSGC
		private WeakReference weakRef;

		internal java.lang.invoke.MethodType Type
		{
			get { return weakRef == null ? null : (java.lang.invoke.MethodType)weakRef.Target; }
		}

		internal bool TrySetType(java.lang.invoke.MethodType newType)
		{
			if (weakRef == null)
			{
				return Interlocked.CompareExchange(ref weakRef, new WeakReference(newType), null) == null;
			}
			return Type == newType;
		}
#else
		private java.lang.invoke.MethodType type;

		internal java.lang.invoke.MethodType Type
		{
			get { return type; }
		}

		internal bool TrySetType(java.lang.invoke.MethodType newType)
		{
			Interlocked.CompareExchange(ref type, newType, null);
			return type == newType;
		}
#endif
		internal T fixedArg;
		internal T varArg;
	}

	[StructLayout(LayoutKind.Explicit)]
	public struct DoubleConverter
	{
		[FieldOffset(0)]
		private double d;
		[FieldOffset(0)]
		private long l;

		public static long ToLong(double value, ref DoubleConverter converter)
		{
			converter.d = value;
			return converter.l;
		}

		public static double ToDouble(long value, ref DoubleConverter converter)
		{
			converter.l = value;
			return converter.d;
		}
	}

	[StructLayout(LayoutKind.Explicit)]
	public struct FloatConverter
	{
		[FieldOffset(0)]
		private float f;
		[FieldOffset(0)]
		private int i;

		public static int ToInt(float value, ref FloatConverter converter)
		{
			converter.f = value;
			return converter.i;
		}

		public static float ToFloat(int value, ref FloatConverter converter)
		{
			converter.i = value;
			return converter.f;
		}
	}

	public struct MHA<T1, T2, T3, T4, T5, T6, T7, T8>
	{
		public T1 t1;
		public T2 t2;
		public T3 t3;
		public T4 t4;
		public T5 t5;
		public T6 t6;
		public T7 t7;
		public T8 t8;

		public MHA(T1 t1, T2 t2, T3 t3, T4 t4, T5 t5, T6 t6, T7 t7, T8 t8)
		{
			this.t1 = t1;
			this.t2 = t2;
			this.t3 = t3;
			this.t4 = t4;
			this.t5 = t5;
			this.t6 = t6;
			this.t7 = t7;
			this.t8 = t8;
		}
	}

	public delegate void MHV();
	public delegate void MHV<T1>(T1 t1);
	public delegate void MHV<T1, T2>(T1 t1, T2 t2);
	public delegate void MHV<T1, T2, T3>(T1 t1, T2 t2, T3 t3);
	public delegate void MHV<T1, T2, T3, T4>(T1 t1, T2 t2, T3 t3, T4 t4);
	public delegate void MHV<T1, T2, T3, T4, T5>(T1 t1, T2 t2, T3 t3, T4 t4, T5 t5);
	public delegate void MHV<T1, T2, T3, T4, T5, T6>(T1 t1, T2 t2, T3 t3, T4 t4, T5 t5, T6 t6);
	public delegate void MHV<T1, T2, T3, T4, T5, T6, T7>(T1 t1, T2 t2, T3 t3, T4 t4, T5 t5, T6 t6, T7 t7);
	public delegate void MHV<T1, T2, T3, T4, T5, T6, T7, T8>(T1 t1, T2 t2, T3 t3, T4 t4, T5 t5, T6 t6, T7 t7, T8 t8);

	public delegate TResult MH<TResult>();
	public delegate TResult MH<T1, TResult>(T1 t1);
	public delegate TResult MH<T1, T2, TResult>(T1 t1, T2 t2);
	public delegate TResult MH<T1, T2, T3, TResult>(T1 t1, T2 t2, T3 t3);
	public delegate TResult MH<T1, T2, T3, T4, TResult>(T1 t1, T2 t2, T3 t3, T4 t4);
	public delegate TResult MH<T1, T2, T3, T4, T5, TResult>(T1 t1, T2 t2, T3 t3, T4 t4, T5 t5);
	public delegate TResult MH<T1, T2, T3, T4, T5, T6, TResult>(T1 t1, T2 t2, T3 t3, T4 t4, T5 t5, T6 t6);
	public delegate TResult MH<T1, T2, T3, T4, T5, T6, T7, TResult>(T1 t1, T2 t2, T3 t3, T4 t4, T5 t5, T6 t6, T7 t7);
	public delegate TResult MH<T1, T2, T3, T4, T5, T6, T7, T8, TResult>(T1 t1, T2 t2, T3 t3, T4 t4, T5 t5, T6 t6, T7 t7, T8 t8);

	public static class LiveObjectHolder<T>
	{
		public static object[] values;
	}
}