/// <summary>
/// Injects the garbage collector related IL ops into the specified method.
/// </summary>
/// <param name="TheLibrary">The library being compiled.</param>
/// <param name="theMethodInfo">The method to inject ops into.</param>
/// <param name="theILBlock">The IL block for the method to inject ops into.</param>
private static void InjectGC(ILLibrary TheLibrary, Types.MethodInfo theMethodInfo, ILBlock theILBlock)
{
if (theMethodInfo.ApplyGC)
{
// Find the index of the MethodStart op
int MethodStartOpPos = theILBlock.PositionOf(theILBlock.ILOps.Where(x => x is ILOps.MethodStart).First());
// Inject ops for incrementing ref. count of args at start of method
int InjectIncArgsRefCountPos = MethodStartOpPos + 1;
foreach (Types.VariableInfo argInfo in theMethodInfo.ArgumentInfos)
{
if (argInfo.TheTypeInfo.IsGCManaged)
{
theILBlock.ILOps.Insert(InjectIncArgsRefCountPos, new ILOp()
{
opCode = System.Reflection.Emit.OpCodes.Ldarg,
ValueBytes = BitConverter.GetBytes(argInfo.Position)
});
theILBlock.ILOps.Insert(InjectIncArgsRefCountPos + 1, new ILOp()
{
opCode = System.Reflection.Emit.OpCodes.Call,
MethodToCall = ILLibrary.SpecialMethods[typeof(Attributes.IncrementRefCountMethodAttribute)].First().UnderlyingInfo
});
}
}
// The following two things can be done within the same loop:
// Inject ops for inc./dec. ref. counts of objects when written to:
// - Arguments / Locals
// - Fields / Static Fields
// - Elements of Arrays
// Add Cleanup Block and Inject finally-block ops for it
// - Also remember the op for storing return value (if any)
ILPreprocessState preprocessState = new ILPreprocessState()
{
TheILLibrary = TheLibrary,
Input = theILBlock,
CurrentStackFrame = new StackFrame()
};
ExceptionHandledBlock CleanupExBlock = new ExceptionHandledBlock();
for (int opIndx = 0; opIndx < theILBlock.ILOps.Count; opIndx++)
{
ILOp currOp = theILBlock.ILOps[opIndx];
bool IncRefCount = false;
int incOpIndexBy = 0;
switch ((ILOp.OpCodes)currOp.opCode.Value)
{
case ILOp.OpCodes.Stsfld:
#region Stsfld
{
int metadataToken = Utilities.ReadInt32(currOp.ValueBytes, 0);
System.Reflection.FieldInfo theField = theMethodInfo.UnderlyingInfo.Module.ResolveField(metadataToken);
Types.TypeInfo theFieldTypeInfo = TheLibrary.GetTypeInfo(theField.FieldType);
if (theFieldTypeInfo.IsGCManaged)
{
theILBlock.ILOps.Insert(opIndx, new ILOp()
{
opCode = System.Reflection.Emit.OpCodes.Ldsfld,
ValueBytes = currOp.ValueBytes
});
theILBlock.ILOps.Insert(opIndx + 1, new ILOp()
{
opCode = System.Reflection.Emit.OpCodes.Call,
MethodToCall = ILLibrary.SpecialMethods[typeof(Attributes.DecrementRefCountMethodAttribute)].First().UnderlyingInfo
});
IncRefCount = true;
incOpIndexBy = 2;
}
}
#endregion
break;
case ILOp.OpCodes.Stloc:
case ILOp.OpCodes.Stloc_0:
case ILOp.OpCodes.Stloc_1:
case ILOp.OpCodes.Stloc_2:
case ILOp.OpCodes.Stloc_3:
case ILOp.OpCodes.Stloc_S:
#region Stloc
{
UInt16 localIndex = 0;
switch ((ILOp.OpCodes)currOp.opCode.Value)
{
case ILOp.OpCodes.Stloc:
localIndex = (UInt16)Utilities.ReadInt16(currOp.ValueBytes, 0);
break;
case ILOp.OpCodes.Stloc_0:
localIndex = 0;
break;
case ILOp.OpCodes.Stloc_1:
localIndex = 1;
break;
case ILOp.OpCodes.Stloc_2:
localIndex = 2;
break;
case ILOp.OpCodes.Stloc_3:
localIndex = 3;
break;
case ILOp.OpCodes.Stloc_S:
localIndex = (UInt16)currOp.ValueBytes[0];
break;
}
Types.TypeInfo LocalTypeInfo = theMethodInfo.LocalInfos[localIndex].TheTypeInfo;
if (LocalTypeInfo.IsGCManaged)
{
theILBlock.ILOps.Insert(opIndx, new ILOp()
{
opCode = System.Reflection.Emit.OpCodes.Ldloc,
ValueBytes = BitConverter.GetBytes(localIndex)
});
theILBlock.ILOps.Insert(opIndx + 1, new ILOp()
{
opCode = System.Reflection.Emit.OpCodes.Call,
MethodToCall = ILLibrary.SpecialMethods[typeof(Attributes.DecrementRefCountMethodAttribute)].First().UnderlyingInfo
});
IncRefCount = true;
incOpIndexBy = 2;
}
}
#endregion
break;
case ILOp.OpCodes.Stfld:
#region Stfld
{
int metadataToken = Utilities.ReadInt32(currOp.ValueBytes, 0);
System.Reflection.FieldInfo theField = theMethodInfo.UnderlyingInfo.Module.ResolveField(metadataToken);
Types.TypeInfo theFieldTypeInfo = TheLibrary.GetTypeInfo(theField.FieldType);
if (theFieldTypeInfo.IsGCManaged)
{
// Items on stack:
// - Object reference
// - (New) Value to store
//
// We want to load the current value of the field
// for which we must duplicate the object ref
// But first, we must remove the (new) value to store
// off the stack, while also storing it to put back
// on the stack after so the store can continue
//
// So:
// 1. Switch value to store and object ref on stack
// 3. Duplicate the object ref
// 4. Load the field value
// 5. Call dec ref count
// 6. Switch value to store and object ref back again
//USE A SWITCH STACK ITEMS OP!!
theILBlock.ILOps.Insert(opIndx, new ILOps.StackSwitch()
{
StackSwitch_Items = 2
});
theILBlock.ILOps.Insert(opIndx + 1, new ILOp()
{
opCode = System.Reflection.Emit.OpCodes.Dup
});
theILBlock.ILOps.Insert(opIndx + 2, new ILOp()
{
opCode = System.Reflection.Emit.OpCodes.Ldfld,
ValueBytes = currOp.ValueBytes
});
theILBlock.ILOps.Insert(opIndx + 3, new ILOp()
{
opCode = System.Reflection.Emit.OpCodes.Call,
MethodToCall = ILLibrary.SpecialMethods[typeof(Attributes.DecrementRefCountMethodAttribute)].First().UnderlyingInfo
});
theILBlock.ILOps.Insert(opIndx + 4, new ILOps.StackSwitch()
{
StackSwitch_Items = 2
});
IncRefCount = true;
incOpIndexBy = 5;
}
}
#endregion
break;
case ILOp.OpCodes.Stelem:
case ILOp.OpCodes.Stelem_Ref:
#region Stelem / Stelem_Ref
{
bool doDecrement = false;
bool isRefOp = false;
if ((ILOp.OpCodes)currOp.opCode.Value == ILOp.OpCodes.Stelem_Ref)
{
doDecrement = preprocessState.CurrentStackFrame.Stack.Peek().isGCManaged;
isRefOp = true;
}
else
{
int metadataToken = Utilities.ReadInt32(currOp.ValueBytes, 0);
Type elementType = theMethodInfo.UnderlyingInfo.Module.ResolveType(metadataToken);
doDecrement = TheLibrary.GetTypeInfo(elementType).IsGCManaged;
}
if (doDecrement)
{
// Items on stack:
// - Array reference
// - Index
// - (New) Value to store
//
// We want to load the current value of the element at Index in the array
// for which we must duplicate the array ref and index
// But first, we must remove the (new) value to store
// off the stack, while also storing it to put back
// on the stack after so the store can continue
//
// So:
// 1. Switch (rotate) 1 times the top 3 values so that index is on top
// 2. Duplicate the index
// 3. Switch (rotate) 2 times the top 4 values so that array ref is on top
// 4. Duplicate the array ref
// 5. Switch (rotate) 4 times the top 5 values so that duplicate array ref and index are on top
// 6. Do LdElem op to load existing element value
// 7. Call GC.DecrementRefCount
// 8. Switch (rotate) 1 times the top 3 values so that the stack is in its original state
// (9. Continue to increment ref count as normal)
//
// The following is a diagram of the stack manipulation occurring here:
// Key: A=Array ref, I=Index, V=Value to store, E=Loaded element
// Top-most stack item appears last
//
// 1) Rotate x 1 2) Duplicate 3) Rot x 2 4) Dup
// A,I,V ---------> V,A,I ---------> V,A,I,I ---------> I,I,V,A ---------> I,I,V,A,A
//
//
// 5) Rot x 4 6) Ldelem 7) Call GC (Dec)
// I,I,V,A,A ---------> I,V,A,A,I ---------> I,V,A,E ---------> I,V,A
//
//
// 8) Rot x 1 9) Dup 10) Call GC (Inc)
// I,V,A ---------> A,I,V ---------> A,I,V,V ---------> A,I,V
#region 1.
theILBlock.ILOps.Insert(opIndx, new ILOps.StackSwitch()
{
ValueBytes = BitConverter.GetBytes(3),
StackSwitch_Items = 3
});
incOpIndexBy++;
#endregion
#region 2.
theILBlock.ILOps.Insert(opIndx + incOpIndexBy, new ILOp()
{
opCode = System.Reflection.Emit.OpCodes.Dup
});
incOpIndexBy++;
#endregion
#region 3.
theILBlock.ILOps.Insert(opIndx + incOpIndexBy, new ILOps.StackSwitch()
{
ValueBytes = BitConverter.GetBytes(4),
StackSwitch_Items = 4
});
incOpIndexBy++;
theILBlock.ILOps.Insert(opIndx + incOpIndexBy, new ILOps.StackSwitch()
{
ValueBytes = BitConverter.GetBytes(4),
StackSwitch_Items = 4
});
incOpIndexBy++;
#endregion
#region 4.
theILBlock.ILOps.Insert(opIndx + incOpIndexBy, new ILOp()
{
opCode = System.Reflection.Emit.OpCodes.Dup
});
incOpIndexBy++;
#endregion
#region 5.
theILBlock.ILOps.Insert(opIndx + incOpIndexBy, new ILOps.StackSwitch()
{
ValueBytes = BitConverter.GetBytes(5),
StackSwitch_Items = 5
});
incOpIndexBy++;
theILBlock.ILOps.Insert(opIndx + incOpIndexBy, new ILOps.StackSwitch()
{
ValueBytes = BitConverter.GetBytes(5),
StackSwitch_Items = 5
});
incOpIndexBy++;
theILBlock.ILOps.Insert(opIndx + incOpIndexBy, new ILOps.StackSwitch()
{
ValueBytes = BitConverter.GetBytes(5),
StackSwitch_Items = 5
});
incOpIndexBy++;
theILBlock.ILOps.Insert(opIndx + incOpIndexBy, new ILOps.StackSwitch()
{
ValueBytes = BitConverter.GetBytes(5),
StackSwitch_Items = 5
});
incOpIndexBy++;
#endregion
#region 6.
theILBlock.ILOps.Insert(opIndx + incOpIndexBy, new ILOp()
{
opCode = isRefOp ? System.Reflection.Emit.OpCodes.Ldelem_Ref : System.Reflection.Emit.OpCodes.Ldelem,
ValueBytes = currOp.ValueBytes
});
incOpIndexBy++;
#endregion
#region 7.
theILBlock.ILOps.Insert(opIndx + incOpIndexBy, new ILOp()
{
opCode = System.Reflection.Emit.OpCodes.Call,
MethodToCall = ILLibrary.SpecialMethods[typeof(Attributes.DecrementRefCountMethodAttribute)].First().UnderlyingInfo
});
incOpIndexBy++;
#endregion
#region 8.
theILBlock.ILOps.Insert(opIndx + incOpIndexBy, new ILOps.StackSwitch()
{
ValueBytes = BitConverter.GetBytes(3),
StackSwitch_Items = 3
});
incOpIndexBy++;
#endregion
IncRefCount = true;
}
}
#endregion
break;
case ILOp.OpCodes.Starg:
case ILOp.OpCodes.Starg_S:
#region Starg
{
UInt16 index = (ILOp.OpCodes)currOp.opCode.Value == ILOp.OpCodes.Starg_S ?
(UInt16)currOp.ValueBytes[0] : (UInt16)Utilities.ReadInt16(currOp.ValueBytes, 0);
if (theMethodInfo.ArgumentInfos[index].TheTypeInfo.IsGCManaged)
{
theILBlock.ILOps.Insert(opIndx, new ILOp()
{
opCode = System.Reflection.Emit.OpCodes.Ldarg,
ValueBytes = BitConverter.GetBytes(index)
});
theILBlock.ILOps.Insert(opIndx + 1, new ILOp()
{
opCode = System.Reflection.Emit.OpCodes.Call,
MethodToCall = ILLibrary.SpecialMethods[typeof(Attributes.DecrementRefCountMethodAttribute)].First().UnderlyingInfo
});
IncRefCount = true;
incOpIndexBy = 2;
}
}
#endregion
break;
}
if (IncRefCount &&
!preprocessState.CurrentStackFrame.Stack.Peek().isNewGCObject)
{
theILBlock.ILOps.Insert(opIndx + incOpIndexBy, new ILOp()
{
opCode = System.Reflection.Emit.OpCodes.Dup
});
incOpIndexBy++;
theILBlock.ILOps.Insert(opIndx + incOpIndexBy, new ILOp()
{
opCode = System.Reflection.Emit.OpCodes.Call,
MethodToCall = ILLibrary.SpecialMethods[typeof(Attributes.IncrementRefCountMethodAttribute)].First().UnderlyingInfo
});
incOpIndexBy++;
}
// If op changed
if (theILBlock.ILOps[opIndx] != currOp)
{
theILBlock.ILOps[opIndx].Offset = currOp.Offset;
theILBlock.ILOps[opIndx].BytesSize = currOp.BytesSize;
}
// <= is correct. E.g. if 1 extra op added, incOpIndex=1 so <= results in currOp processed
// + extra op processed
bool UseNextOpAsCleanupStart = false;
for (int i = 0; i <= incOpIndexBy; i++)
{
currOp = theILBlock.ILOps[opIndx];
if (UseNextOpAsCleanupStart)
{
UseNextOpAsCleanupStart = false;
CleanupExBlock.Offset = currOp.Offset;
}
if (currOp is ILOps.MethodStart)
{
TargetArchitecture.MethodStartOp.PerformStackOperations(preprocessState, theILBlock.ILOps[opIndx]);
UseNextOpAsCleanupStart = true;
}
else if (currOp is ILOps.MethodEnd)
{
TargetArchitecture.MethodEndOp.PerformStackOperations(preprocessState, theILBlock.ILOps[opIndx]);
}
else if (currOp is ILOps.StackSwitch)
{
TargetArchitecture.StackSwitchOp.PerformStackOperations(preprocessState, theILBlock.ILOps[opIndx]);
}
else
{
// Leave unsupported ops for the IL Scanner to deal with (or later code e.g. castclass op)
if (TargetArchitecture.TargetILOps.ContainsKey((ILOp.OpCodes)currOp.opCode.Value))
{
ILOp ConverterOp = TargetArchitecture.TargetILOps[(ILOp.OpCodes)currOp.opCode.Value];
ConverterOp.PerformStackOperations(preprocessState, currOp);
}
}
if (i > 0)
{
opIndx++;
}
}
}
if (theMethodInfo.ArgumentInfos.Count > 0 ||
theMethodInfo.LocalInfos.Count > 0)
{
bool AddCleanupBlock = false;
foreach (Types.VariableInfo anArgInfo in theMethodInfo.ArgumentInfos)
{
if (anArgInfo.TheTypeInfo.IsGCManaged)
{
AddCleanupBlock = true;
break;
}
}
if (!AddCleanupBlock)
{
foreach (Types.VariableInfo aLocInfo in theMethodInfo.LocalInfos)
{
if (aLocInfo.TheTypeInfo.IsGCManaged)
{
AddCleanupBlock = true;
break;
}
}
}
if (AddCleanupBlock)
{
ILOp lastOp = theILBlock.ILOps.Last();
int lastOpOffset = lastOp.Offset;
int lastOpIndex = theILBlock.ILOps.Count - 1;
bool MethodHasReturnValue = false;
// If there is a return value, we will need to temp store it
if (theMethodInfo.UnderlyingInfo is System.Reflection.MethodInfo)
{
Type returnType = ((System.Reflection.MethodInfo)theMethodInfo.UnderlyingInfo).ReturnType;
//Void return type = no return value
if (returnType != typeof(void))
{
// Add local variable for storing return value
int lastLocalOffset = theMethodInfo.LocalInfos.Count > 0 ? theMethodInfo.LocalInfos.Last().Offset : 0;
int lastLocalSize = theMethodInfo.LocalInfos.Count > 0 ? theMethodInfo.LocalInfos.Last().TheTypeInfo.SizeOnStackInBytes : 0;
theMethodInfo.LocalInfos.Add(new Types.VariableInfo()
{
UnderlyingType = returnType,
TheTypeInfo = TheLibrary.GetTypeInfo(returnType),
Position = theMethodInfo.LocalInfos.Count,
Offset = lastLocalOffset + lastLocalSize
});
// Add op for storing return value, update op offsets
theILBlock.ILOps.Insert(lastOpIndex, new ILOp()
{
opCode = System.Reflection.Emit.OpCodes.Stloc,
Offset = lastOpOffset,
BytesSize = lastOp.BytesSize,
ValueBytes = BitConverter.GetBytes(theMethodInfo.LocalInfos.Count - 1)
});
lastOpIndex++;
MethodHasReturnValue = true;
}
}
ILOp leaveOp;
// Add the Leave op of the try-block
theILBlock.ILOps.Insert(lastOpIndex, leaveOp = new ILOp()
{
opCode = System.Reflection.Emit.OpCodes.Leave,
Offset = lastOpOffset,
BytesSize = lastOp.BytesSize,
ValueBytes = BitConverter.GetBytes(0)
});
lastOpIndex++;
FinallyBlock CleanupFinallyBlock = new FinallyBlock()
{
Offset = lastOpOffset + lastOp.BytesSize,
Length = 0
};
CleanupExBlock.Length = lastOpOffset - CleanupExBlock.Offset;
CleanupExBlock.FinallyBlocks.Add(CleanupFinallyBlock);
int cleanupOpsOffset = lastOpOffset + 1;
// Add cleanup code for local variables (including the return value local)
foreach (Types.VariableInfo aLocInfo in theMethodInfo.LocalInfos)
{
if (aLocInfo.TheTypeInfo.IsGCManaged)
{
theILBlock.ILOps.Insert(lastOpIndex, new ILOp()
{
opCode = System.Reflection.Emit.OpCodes.Ldloc,
Offset = cleanupOpsOffset,
BytesSize = 1,
ValueBytes = BitConverter.GetBytes(aLocInfo.Position)
});
cleanupOpsOffset++;
lastOpIndex++;
theILBlock.ILOps.Insert(lastOpIndex, new ILOp()
{
opCode = System.Reflection.Emit.OpCodes.Call,
Offset = cleanupOpsOffset,
BytesSize = 1,
MethodToCall = ILLibrary.SpecialMethods[typeof(Attributes.DecrementRefCountMethodAttribute)].First().UnderlyingInfo
});
cleanupOpsOffset++;
lastOpIndex++;
CleanupFinallyBlock.Length += 2;
}
}
// Add cleanup code for arguments
foreach (Types.VariableInfo anArgInfo in theMethodInfo.ArgumentInfos)
{
if (anArgInfo.TheTypeInfo.IsGCManaged)
{
theILBlock.ILOps.Insert(lastOpIndex, new ILOp()
{
opCode = System.Reflection.Emit.OpCodes.Ldarg,
Offset = cleanupOpsOffset,
BytesSize = 1,
ValueBytes = BitConverter.GetBytes(anArgInfo.Position)
});
cleanupOpsOffset++;
lastOpIndex++;
theILBlock.ILOps.Insert(lastOpIndex, new ILOp()
{
opCode = System.Reflection.Emit.OpCodes.Call,
Offset = cleanupOpsOffset,
BytesSize = 1,
MethodToCall = ILLibrary.SpecialMethods[typeof(Attributes.DecrementRefCountMethodAttribute)].First().UnderlyingInfo
});
cleanupOpsOffset++;
lastOpIndex++;
CleanupFinallyBlock.Length += 2;
}
}
// Add end finally op
theILBlock.ILOps.Insert(lastOpIndex, leaveOp.LoadAtILOpAfterOp = new ILOp()
{
opCode = System.Reflection.Emit.OpCodes.Endfinally,
Offset = cleanupOpsOffset,
BytesSize = 1
});
cleanupOpsOffset++;
lastOpIndex++;
CleanupFinallyBlock.Length++;
// Add restore return value op
if (MethodHasReturnValue)
{
theILBlock.ILOps.Insert(lastOpIndex, new ILOp()
{
opCode = System.Reflection.Emit.OpCodes.Ldloc,
Offset = cleanupOpsOffset,
BytesSize = 1,
ValueBytes = BitConverter.GetBytes(theMethodInfo.LocalInfos.Count - 1)
});
cleanupOpsOffset++;
lastOpIndex++;
}
// Add ex block to the method
theILBlock.ExceptionHandledBlocks.Add(CleanupExBlock);
// Replace any Ret ops contained within Cleanup Block with:
// - Op to store return value (if any)
// - Leave op
bool Inside = false;
for(int opIndx = 0; opIndx < theILBlock.ILOps.Count; opIndx++)
{
if (theILBlock.ILOps[opIndx].Offset > CleanupExBlock.Offset + CleanupExBlock.Length)
{
break;
}
else if (theILBlock.ILOps[opIndx].Offset >= CleanupExBlock.Offset)
{
Inside = true;
}
if (Inside &&
(ILOp.OpCodes)theILBlock.ILOps[opIndx].opCode.Value == ILOp.OpCodes.Ret)
{
ILOp ARetOp = theILBlock.ILOps[opIndx];
theILBlock.ILOps.RemoveAt(opIndx);
if (MethodHasReturnValue)
{
theILBlock.ILOps.Insert(opIndx, new ILOp()
{
opCode = System.Reflection.Emit.OpCodes.Stloc,
Offset = ARetOp.Offset,
ValueBytes = BitConverter.GetBytes(theMethodInfo.LocalInfos.Count - 1)
});
theILBlock.ILOps.Insert(opIndx + 1, new ILOp()
{
Offset = ARetOp.Offset,
opCode = System.Reflection.Emit.OpCodes.Leave,
ValueBytes = BitConverter.GetBytes(0),
LoadAtILOpAfterOp = leaveOp.LoadAtILOpAfterOp
});
}
else
{
theILBlock.ILOps.Insert(opIndx, new ILOp()
{
Offset = ARetOp.Offset,
opCode = System.Reflection.Emit.OpCodes.Leave,
ValueBytes = BitConverter.GetBytes(0),
LoadAtILOpAfterOp = leaveOp.LoadAtILOpAfterOp
});
}
}
}
}
}
}
}
/// <summary>
/// Handles catch handles (of exception blocks) for the specified method.
/// </summary>
/// <param name="theMethodInfo">The method to handle.</param>
/// <param name="theILBlock">The IL block for the method to handle.</param>
private static void DealWithCatchHandlers(Types.MethodInfo theMethodInfo, ILBlock theILBlock)
{
foreach (ExceptionHandledBlock exBlock in theILBlock.ExceptionHandledBlocks)
{
#region Catch-sections
// Strip the first pop of catch-handler
foreach (CatchBlock aCatchBlock in exBlock.CatchBlocks)
{
ILOp catchPopOp = theILBlock.At(aCatchBlock.Offset);
int pos = theILBlock.PositionOf(catchPopOp);
theILBlock.ILOps.RemoveAt(pos);
theILBlock.ILOps.Insert(pos, new ILOp()
{
opCode = System.Reflection.Emit.OpCodes.Nop,
Offset = catchPopOp.Offset,
BytesSize = catchPopOp.BytesSize
});
}
#endregion
}
}
/// <summary>
/// Injects the try-catch-finally related IL ops into the specified method.
/// </summary>
/// <param name="theMethodInfo">The method to inject ops into.</param>
/// <param name="theILBlock">The IL block for the method to inject ops into.</param>
private static void InjectTryCatchFinally(Types.MethodInfo theMethodInfo, ILBlock theILBlock)
{
// Replace Leave and Leave_S ops
for (int i = 0; i < theILBlock.ILOps.Count; i++)
{
ILOp theOp = theILBlock.ILOps[i];
if ((ILOp.OpCodes)theOp.opCode.Value == ILOp.OpCodes.Leave ||
(ILOp.OpCodes)theOp.opCode.Value == ILOp.OpCodes.Leave_S)
{
theILBlock.ILOps.RemoveAt(i);
int ILOffset = 0;
if (theOp.LoadAtILOpAfterOp == null)
{
if ((int)theOp.opCode.Value == (int)ILOp.OpCodes.Leave)
{
ILOffset = BitConverter.ToInt32(theOp.ValueBytes, 0);
}
else
{
ILOffset = (int)theOp.ValueBytes[0];
}
}
theILBlock.ILOps.Insert(i, new ILOp()
{
Offset = theOp.Offset,
BytesSize = theOp.BytesSize,
opCode = System.Reflection.Emit.OpCodes.Ldftn,
LoadAtILOffset = theOp.NextOffset + ILOffset,
LoadAtILOpAfterOp = theOp.LoadAtILOpAfterOp,
MethodToCall = theILBlock.TheMethodInfo.UnderlyingInfo
});
theILBlock.ILOps.Insert(i + 1, new ILOp()
{
opCode = System.Reflection.Emit.OpCodes.Call,
MethodToCall = ILLibrary.SpecialMethods[typeof(Attributes.ExceptionsHandleLeaveMethodAttribute)].First().UnderlyingInfo
});
i++;
}
else if ((int)theOp.opCode.Value == (int)ILOp.OpCodes.Endfinally)
{
//Endfinally is for leaving a (critical) finally section
//We handle it by a higher-level implementation rather than
// leaving it to each architecture to implement.
//Endfinally is handled by inserting a call to the Exceptions.HandleEndFinally method
theILBlock.ILOps.RemoveAt(i);
ILOp newOp;
theILBlock.ILOps.Insert(i, newOp = new ILOp()
{
Offset = theOp.Offset,
BytesSize = theOp.BytesSize,
opCode = System.Reflection.Emit.OpCodes.Call,
MethodToCall = ILLibrary.SpecialMethods[typeof(Attributes.ExceptionsHandleEndFinallyMethodAttribute)].First().UnderlyingInfo
});
//Replace references to this endfinally op
for (int j = 0; j < theILBlock.ILOps.Count; j++)
{
if (theILBlock.ILOps[j].LoadAtILOpAfterOp == theOp)
{
theILBlock.ILOps[j].LoadAtILOpAfterOp = newOp;
}
}
}
}
foreach (ExceptionHandledBlock exBlock in theILBlock.ExceptionHandledBlocks)
{
#region Try-sections
// Insert the start of try-block
// Also remember that other ops (e.g. branch and leave) can hold references
// to the first op INSIDE a try block, even if they themselves are OUTSIDE
// the block. This means we need to correct which op has the Offset value
// set so those ops point at the new start op of the try block.
//Consists of adding a new ExceptionHandlerInfos
// built from the info in exBlock so we:
// - Add infos for all finally blocks first
// - Then add infos for all catch blocks
// Since finally code is always run after catch code in C#,
// by adding catch handlers after finally handlers, they
// appear as the inner-most exception handlers and so get
// run before finally handlers.
//To add a new ExceptionHandlerInfo we must set up args for
// calling Exceptions.AddExceptionHandlerInfo:
// 1. We load a pointer to the handler
// - This is calculated from an offset from the start of the function to the handler
// 2. We load a pointer to the filter
// - This is calculated from an offset from the start of the function to the filter
// Note: Filter has not been implemented as an actual filter.
// At the moment, 0x00000000 indicates a finally handler,
// 0xFFFFFFFF indicates no filter block
// (i.e. an unfiltered catch handler)
// 0xXXXXXXXX has undetermined behaviour!
//For each finally block:
int insertPos = theILBlock.PositionOf(theILBlock.At(exBlock.Offset));
foreach (FinallyBlock finBlock in exBlock.FinallyBlocks)
{
// 1. Load the pointer to the handler code:
theILBlock.ILOps.Insert(insertPos++, new ILOp()
{
opCode = System.Reflection.Emit.OpCodes.Ldftn,
MethodToCall = theMethodInfo.UnderlyingInfo,
LoadAtILOffset = finBlock.Offset
});
theILBlock.ILOps.Insert(insertPos++, new ILOp()
{
opCode = System.Reflection.Emit.OpCodes.Ldc_I4,
ValueBytes = BitConverter.GetBytes(0x00000000)
});
theILBlock.ILOps.Insert(insertPos++, new ILOp()
{
opCode = System.Reflection.Emit.OpCodes.Call,
MethodToCall = ILLibrary.SpecialMethods[typeof(Attributes.AddExceptionHandlerInfoMethodAttribute)].First().UnderlyingInfo
});
}
foreach (CatchBlock catchBlock in exBlock.CatchBlocks)
{
theILBlock.ILOps.Insert(insertPos++, new ILOp()
{
opCode = System.Reflection.Emit.OpCodes.Ldftn,
MethodToCall = theMethodInfo.UnderlyingInfo,
LoadAtILOffset = catchBlock.Offset
});
theILBlock.ILOps.Insert(insertPos++, new ILOp()
{
opCode = System.Reflection.Emit.OpCodes.Ldc_I4,
ValueBytes = BitConverter.GetBytes(0xFFFFFFFF)
});
theILBlock.ILOps.Insert(insertPos++, new ILOp()
{
opCode = System.Reflection.Emit.OpCodes.Call,
MethodToCall = ILLibrary.SpecialMethods[typeof(Attributes.AddExceptionHandlerInfoMethodAttribute)].First().UnderlyingInfo
});
}
#endregion
}
}
/// <summary>
/// Gets the position (index) of the specified IL op.
/// </summary>
/// <param name="anOp">The op to get the position of.</param>
/// <returns>The position.</returns>
public int PositionOf(ILOp anOp)
{
return(Input.PositionOf(anOp));
}