Ejemplo n.º 1
0
        /// <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
                                    });
                                }
                            }
                        }
                    }
                }
            }
        }
Ejemplo n.º 2
0
        /// <summary>
        /// Reads a non-plugged method.
        /// </summary>
        /// <param name="aMethodInfo">The method to read.</param>
        /// <returns>The new IL block for the method.</returns>
        public static ILBlock ReadNonPlugged(Types.MethodInfo aMethodInfo)
        {
            ILBlock result = new ILBlock()
            {
                TheMethodInfo = aMethodInfo
            };

            MethodBody methodBody = aMethodInfo.MethodBody;

            //Method body for something like [DelegateType].Invoke() is null.
            //  So just return an empty method if that is this case.
            if (methodBody != null)
            {
                foreach (LocalVariableInfo aLocal in methodBody.LocalVariables)
                {
                    aMethodInfo.LocalInfos.Add(new Types.VariableInfo()
                    {
                        UnderlyingType = aLocal.LocalType,
                        Position       = aLocal.LocalIndex
                    });
                }

                byte[] ILBytes    = methodBody.GetILAsByteArray();
                int    ILBytesPos = 0;

                while (ILBytesPos < ILBytes.Length)
                {
                    OpCode currOpCode;
                    ushort currOpCodeID    = 0;
                    int    currOpBytesSize = 0;

                    if (ILBytes[ILBytesPos] == 0xFE)
                    {
                        currOpCodeID     = (ushort)(0xFE00 + (short)ILBytes[ILBytesPos + 1]);
                        currOpBytesSize += 2;
                    }
                    else
                    {
                        currOpCodeID = (ushort)ILBytes[ILBytesPos];
                        currOpBytesSize++;
                    }
                    currOpCode = AllOpCodes[currOpCodeID];

                    int operandSize = 0;
                    switch (currOpCode.OperandType)
                    {
                        #region Operands

                    case OperandType.InlineBrTarget:
                        operandSize = 4;
                        break;

                    case OperandType.InlineField:
                        operandSize = 4;
                        break;

                    case OperandType.InlineI:
                        operandSize = 4;
                        break;

                    case OperandType.InlineI8:
                        operandSize = 8;
                        break;

                    case OperandType.InlineMethod:
                        operandSize = 4;
                        break;

                    case OperandType.InlineNone:
                        //No operands = no op size
                        break;

                    case OperandType.InlineR:
                        operandSize = 8;
                        break;

                    case OperandType.InlineSig:
                        operandSize = 4;
                        break;

                    case OperandType.InlineString:
                        operandSize = 4;
                        break;

                    case OperandType.InlineSwitch:
                    {
                        uint count = Utilities.ReadUInt32(ILBytes, ILBytesPos + currOpBytesSize);
                        currOpBytesSize += 4;
                        operandSize      = (int)(count * 4);
                    }
                    break;

                    case OperandType.InlineTok:
                        operandSize = 4;
                        break;

                    case OperandType.InlineType:
                        operandSize = 4;
                        break;

                    case OperandType.InlineVar:
                        operandSize = 2;
                        break;

                    case OperandType.ShortInlineBrTarget:
                        operandSize = 1;
                        break;

                    case OperandType.ShortInlineI:
                        operandSize = 1;
                        break;

                    case OperandType.ShortInlineR:
                        operandSize = 4;
                        break;

                    case OperandType.ShortInlineVar:
                        operandSize = 1;
                        break;

                    default:
                        throw new Exception("Unrecognised operand type!");

                        #endregion
                    }

                    MethodBase methodToCall = null;
                    byte[]     valueBytes   = new byte[operandSize];
                    if (operandSize > 0)
                    {
                        Array.Copy(ILBytes, ILBytesPos + currOpBytesSize, valueBytes, 0, operandSize);

                        if (currOpCode.Equals(OpCodes.Call) ||
                            currOpCode.Equals(OpCodes.Calli) ||
                            currOpCode.Equals(OpCodes.Callvirt) ||
                            currOpCode.Equals(OpCodes.Ldftn) ||
                            currOpCode.Equals(OpCodes.Newobj))
                        {
                            int MethodMetadataToken = Utilities.ReadInt32(valueBytes, 0);
                            methodToCall = aMethodInfo.UnderlyingInfo.Module.ResolveMethod(MethodMetadataToken);
                        }
                    }

                    result.ILOps.Add(new ILOp()
                    {
                        opCode       = currOpCode,
                        Offset       = ILBytesPos,
                        BytesSize    = currOpBytesSize + operandSize,
                        ValueBytes   = valueBytes,
                        MethodToCall = methodToCall
                    });

                    ILBytesPos += currOpBytesSize + operandSize;
                }

                foreach (ExceptionHandlingClause aClause in methodBody.ExceptionHandlingClauses)
                {
                    ExceptionHandledBlock exBlock = result.GetExactExceptionHandledBlock(aClause.TryOffset);
                    if (exBlock == null)
                    {
                        exBlock        = new ExceptionHandledBlock();
                        exBlock.Offset = aClause.TryOffset;
                        exBlock.Length = aClause.TryLength;
                        result.ExceptionHandledBlocks.Add(exBlock);
                    }

                    switch (aClause.Flags)
                    {
                    case ExceptionHandlingClauseOptions.Fault:
                    case ExceptionHandlingClauseOptions.Clause:
                    {
                        CatchBlock catchBlock = new CatchBlock()
                        {
                            Offset = aClause.HandlerOffset,
                            Length = aClause.HandlerLength,
                            //Though not used, we may as well set it anyway
                            FilterType = aClause.CatchType
                        };
                        exBlock.CatchBlocks.Add(catchBlock);
                    }
                    break;

                    case ExceptionHandlingClauseOptions.Finally:
                    {
                        FinallyBlock finallyBlock = new FinallyBlock()
                        {
                            Offset = aClause.HandlerOffset,
                            Length = aClause.HandlerLength
                        };
                        exBlock.FinallyBlocks.Add(finallyBlock);
                    }
                    break;

                    default:
                        Logger.LogError("IL0010", "", 0,
                                        "Exception handling clause not supported! Type: " + aClause.Flags.ToString());
                        break;
                    }
                }
            }

            return(result);
        }
Ejemplo n.º 3
0
        /// <summary>
        /// Reads a non-plugged method.
        /// </summary>
        /// <param name="aMethodInfo">The method to read.</param>
        /// <returns>The new IL block for the method.</returns>
        public static ILBlock ReadNonPlugged(Types.MethodInfo aMethodInfo)
        {
            ILBlock result = new ILBlock()
            {
                TheMethodInfo = aMethodInfo
            };

            MethodBody methodBody = aMethodInfo.MethodBody;
            //Method body for something like [DelegateType].Invoke() is null. 
            //  So just return an empty method if that is this case.
            if (methodBody != null)
            {
                foreach (LocalVariableInfo aLocal in methodBody.LocalVariables)
                {
                    aMethodInfo.LocalInfos.Add(new Types.VariableInfo()
                    {
                        UnderlyingType = aLocal.LocalType,
                        Position = aLocal.LocalIndex
                    });
                }

                byte[] ILBytes = methodBody.GetILAsByteArray();
                int ILBytesPos = 0;

                while (ILBytesPos < ILBytes.Length)
                {
                    OpCode currOpCode;
                    ushort currOpCodeID = 0;
                    int currOpBytesSize = 0;

                    if (ILBytes[ILBytesPos] == 0xFE)
                    {
                        currOpCodeID = (ushort)(0xFE00 + (short)ILBytes[ILBytesPos + 1]);
                        currOpBytesSize += 2;
                    }
                    else
                    {
                        currOpCodeID = (ushort)ILBytes[ILBytesPos];
                        currOpBytesSize++;
                    }
                    currOpCode = AllOpCodes[currOpCodeID];

                    int operandSize = 0;
                    switch (currOpCode.OperandType)
                    {
                        #region Operands

                        case OperandType.InlineBrTarget:
                            operandSize = 4;
                            break;
                        case OperandType.InlineField:
                            operandSize = 4;
                            break;
                        case OperandType.InlineI:
                            operandSize = 4;
                            break;
                        case OperandType.InlineI8:
                            operandSize = 8;
                            break;
                        case OperandType.InlineMethod:
                            operandSize = 4;
                            break;
                        case OperandType.InlineNone:
                            //No operands = no op size
                            break;
                        case OperandType.InlineR:
                            operandSize = 8;
                            break;
                        case OperandType.InlineSig:
                            operandSize = 4;
                            break;
                        case OperandType.InlineString:
                            operandSize = 4;
                            break;
                        case OperandType.InlineSwitch:
                            {
                                uint count = Utilities.ReadUInt32(ILBytes, ILBytesPos + currOpBytesSize);
                                currOpBytesSize += 4;
                                operandSize = (int)(count * 4);
                            }
                            break;
                        case OperandType.InlineTok:
                            operandSize = 4;
                            break;
                        case OperandType.InlineType:
                            operandSize = 4;
                            break;
                        case OperandType.InlineVar:
                            operandSize = 2;
                            break;
                        case OperandType.ShortInlineBrTarget:
                            operandSize = 1;
                            break;
                        case OperandType.ShortInlineI:
                            operandSize = 1;
                            break;
                        case OperandType.ShortInlineR:
                            operandSize = 4;
                            break;
                        case OperandType.ShortInlineVar:
                            operandSize = 1;
                            break;
                        default:
                            throw new Exception("Unrecognised operand type!");

                        #endregion
                    }

                    MethodBase methodToCall = null;
                    byte[] valueBytes = new byte[operandSize];
                    if (operandSize > 0)
                    {
                        Array.Copy(ILBytes, ILBytesPos + currOpBytesSize, valueBytes, 0, operandSize);

                        if (currOpCode.Equals(OpCodes.Call) ||
                            currOpCode.Equals(OpCodes.Calli) ||
                            currOpCode.Equals(OpCodes.Callvirt) ||
                            currOpCode.Equals(OpCodes.Ldftn) ||
                            currOpCode.Equals(OpCodes.Newobj))
                        {
                            int MethodMetadataToken = Utilities.ReadInt32(valueBytes, 0);
                            methodToCall = aMethodInfo.UnderlyingInfo.Module.ResolveMethod(MethodMetadataToken);
                        }
                    }

                    result.ILOps.Add(new ILOp()
                    {
                        opCode = currOpCode,
                        Offset = ILBytesPos,
                        BytesSize = currOpBytesSize + operandSize,
                        ValueBytes = valueBytes,
                        MethodToCall = methodToCall
                    });

                    ILBytesPos += currOpBytesSize + operandSize;
                }

                foreach (ExceptionHandlingClause aClause in methodBody.ExceptionHandlingClauses)
                {
                    ExceptionHandledBlock exBlock = result.GetExactExceptionHandledBlock(aClause.TryOffset);
                    if (exBlock == null)
                    {
                        exBlock = new ExceptionHandledBlock();
                        exBlock.Offset = aClause.TryOffset;
                        exBlock.Length = aClause.TryLength;
                        result.ExceptionHandledBlocks.Add(exBlock);
                    }

                    switch (aClause.Flags)
                    {
                        case ExceptionHandlingClauseOptions.Fault:
                        case ExceptionHandlingClauseOptions.Clause:
                            {
                                CatchBlock catchBlock = new CatchBlock()
                                {
                                    Offset = aClause.HandlerOffset,
                                    Length = aClause.HandlerLength,
                                    //Though not used, we may as well set it anyway
                                    FilterType = aClause.CatchType
                                };
                                exBlock.CatchBlocks.Add(catchBlock);
                            }
                            break;
                        case ExceptionHandlingClauseOptions.Finally:
                            {
                                FinallyBlock finallyBlock = new FinallyBlock()
                                {
                                    Offset = aClause.HandlerOffset,
                                    Length = aClause.HandlerLength
                                };
                                exBlock.FinallyBlocks.Add(finallyBlock);
                            }
                            break;
                        default:
                            Logger.LogError("IL0010", "", 0,
                                "Exception handling clause not supported! Type: " + aClause.Flags.ToString());
                            break;
                    }
                }
            }

            return result;
        }