1 files changed, 374 insertions, 0 deletions
diff --git a/ICSharpCode.Decompiler/CecilExtensions.cs b/ICSharpCode.Decompiler/CecilExtensions.cs
new file mode 100644
index 00000000..0c7cb1e4
--- /dev/null
+++ b/ICSharpCode.Decompiler/CecilExtensions.cs
@@ -0,0 +1,374 @@
+// Copyright (c) 2011 AlphaSierraPapa for the SharpDevelop Team
+// 
+// Permission is hereby granted, free of charge, to any person obtaining a copy of this
+// software and associated documentation files (the "Software"), to deal in the Software
+// without restriction, including without limitation the rights to use, copy, modify, merge,
+// publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons
+// to whom the Software is furnished to do so, subject to the following conditions:
+// 
+// The above copyright notice and this permission notice shall be included in all copies or
+// substantial portions of the Software.
+// 
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
+// INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR
+// PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE
+// FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
+// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+// DEALINGS IN THE SOFTWARE.
+
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using Mono.Cecil;
+using Mono.Cecil.Cil;
+
+namespace ICSharpCode.Decompiler
+{
+	/// <summary>
+	/// Cecil helper methods.
+	/// </summary>
+	public static class CecilExtensions
+	{
+		#region GetPushDelta / GetPopDelta
+		public static int GetPushDelta(this Instruction instruction)
+		{
+			OpCode code = instruction.OpCode;
+			switch (code.StackBehaviourPush) {
+				case StackBehaviour.Push0:
+					return 0;
+
+				case StackBehaviour.Push1:
+				case StackBehaviour.Pushi:
+				case StackBehaviour.Pushi8:
+				case StackBehaviour.Pushr4:
+				case StackBehaviour.Pushr8:
+				case StackBehaviour.Pushref:
+					return 1;
+
+				case StackBehaviour.Push1_push1:
+					return 2;
+
+				case StackBehaviour.Varpush:
+					if (code.FlowControl != FlowControl.Call)
+						break;
+
+					IMethodSignature method = (IMethodSignature) instruction.Operand;
+					return IsVoid (method.ReturnType) ? 0 : 1;
+			}
+
+			throw new NotSupportedException ();
+		}
+		
+		public static int? GetPopDelta(this Instruction instruction, MethodDefinition methodDef)
+		{
+			OpCode code = instruction.OpCode;
+			switch (code.StackBehaviourPop) {
+				case StackBehaviour.Pop0:
+					return 0;
+				case StackBehaviour.Popi:
+				case StackBehaviour.Popref:
+				case StackBehaviour.Pop1:
+					return 1;
+
+				case StackBehaviour.Pop1_pop1:
+				case StackBehaviour.Popi_pop1:
+				case StackBehaviour.Popi_popi:
+				case StackBehaviour.Popi_popi8:
+				case StackBehaviour.Popi_popr4:
+				case StackBehaviour.Popi_popr8:
+				case StackBehaviour.Popref_pop1:
+				case StackBehaviour.Popref_popi:
+					return 2;
+
+				case StackBehaviour.Popi_popi_popi:
+				case StackBehaviour.Popref_popi_popi:
+				case StackBehaviour.Popref_popi_popi8:
+				case StackBehaviour.Popref_popi_popr4:
+				case StackBehaviour.Popref_popi_popr8:
+				case StackBehaviour.Popref_popi_popref:
+					return 3;
+
+				case StackBehaviour.PopAll:
+					return null;
+
+				case StackBehaviour.Varpop:
+					if (code == OpCodes.Ret)
+						return methodDef.ReturnType.IsVoid() ? 0 : 1;
+
+					if (code.FlowControl != FlowControl.Call)
+						break;
+
+					IMethodSignature method = (IMethodSignature) instruction.Operand;
+					int count = method.HasParameters ? method.Parameters.Count : 0;
+					if (method.HasThis && code != OpCodes.Newobj)
+						++count;
+					if (code == OpCodes.Calli)
+						++count; // calli takes a function pointer in additional to the normal args
+
+					return count;
+			}
+
+			throw new NotSupportedException ();
+		}
+		
+		public static bool IsVoid(this TypeReference type)
+		{
+			while (type is OptionalModifierType || type is RequiredModifierType)
+				type = ((TypeSpecification)type).ElementType;
+			return type.MetadataType == MetadataType.Void;
+		}
+		
+		public static bool IsValueTypeOrVoid(this TypeReference type)
+		{
+			while (type is OptionalModifierType || type is RequiredModifierType)
+				type = ((TypeSpecification)type).ElementType;
+			if (type is ArrayType)
+				return false;
+			return type.IsValueType || type.IsVoid();
+		}
+
+		/// <summary>
+		/// checks if the given TypeReference is one of the following types:
+		/// [sbyte, short, int, long, IntPtr]
+		/// </summary>
+		public static bool IsSignedIntegralType(this TypeReference type)
+		{
+			return type.MetadataType == MetadataType.SByte ||
+				   type.MetadataType == MetadataType.Int16 ||
+				   type.MetadataType == MetadataType.Int32 ||
+				   type.MetadataType == MetadataType.Int64 ||
+				   type.MetadataType == MetadataType.IntPtr;
+		}
+
+		/// <summary>
+		/// checks if the given value is a numeric zero-value.
+		/// NOTE that this only works for types: [sbyte, short, int, long, IntPtr, byte, ushort, uint, ulong, float, double and decimal]
+		/// </summary>
+		public static bool IsZero(this object value)
+		{
+			return value.Equals((sbyte)0) ||
+				   value.Equals((short)0) ||
+				   value.Equals(0) ||
+				   value.Equals(0L) ||
+				   value.Equals(IntPtr.Zero) ||
+				   value.Equals((byte)0) ||
+				   value.Equals((ushort)0) ||
+				   value.Equals(0u) ||
+				   value.Equals(0UL) ||
+				   value.Equals(0.0f) ||
+				   value.Equals(0.0) ||
+				   value.Equals((decimal)0);
+					
+		}
+
+		#endregion
+		
+		/// <summary>
+		/// Gets the (exclusive) end offset of this instruction.
+		/// </summary>
+		public static int GetEndOffset(this Instruction inst)
+		{
+			if (inst == null)
+				throw new ArgumentNullException("inst");
+			return inst.Offset + inst.GetSize();
+		}
+		
+		public static string OffsetToString(int offset)
+		{
+			return string.Format("IL_{0:x4}", offset);
+		}
+		
+		public static HashSet<MethodDefinition> GetAccessorMethods(this TypeDefinition type)
+		{
+			HashSet<MethodDefinition> accessorMethods = new HashSet<MethodDefinition>();
+			foreach (var property in type.Properties) {
+				accessorMethods.Add(property.GetMethod);
+				accessorMethods.Add(property.SetMethod);
+				if (property.HasOtherMethods) {
+					foreach (var m in property.OtherMethods)
+						accessorMethods.Add(m);
+				}
+			}
+			foreach (EventDefinition ev in type.Events) {
+				accessorMethods.Add(ev.AddMethod);
+				accessorMethods.Add(ev.RemoveMethod);
+				accessorMethods.Add(ev.InvokeMethod);
+				if (ev.HasOtherMethods) {
+					foreach (var m in ev.OtherMethods)
+						accessorMethods.Add(m);
+				}
+			}
+			return accessorMethods;
+		}
+		
+		public static TypeDefinition ResolveWithinSameModule(this TypeReference type)
+		{
+			if (type != null && type.GetElementType().Module == type.Module)
+				return type.Resolve();
+			else
+				return null;
+		}
+		
+		public static FieldDefinition ResolveWithinSameModule(this FieldReference field)
+		{
+			if (field != null && field.DeclaringType.GetElementType().Module == field.Module)
+				return field.Resolve();
+			else
+				return null;
+		}
+		
+		public static MethodDefinition ResolveWithinSameModule(this MethodReference method)
+		{
+			if (method != null && method.DeclaringType.GetElementType().Module == method.Module)
+				return method.Resolve();
+			else
+				return null;
+		}
+
+		[Obsolete("throwing exceptions is considered a bug")]
+		public static TypeDefinition ResolveOrThrow(this TypeReference typeReference)
+		{
+			var resolved = typeReference.Resolve();
+			if (resolved == null)
+				throw new ReferenceResolvingException();
+			return resolved;
+		}
+
+		public static bool IsCompilerGenerated(this ICustomAttributeProvider provider)
+		{
+			if (provider != null && provider.HasCustomAttributes) {
+				foreach (CustomAttribute a in provider.CustomAttributes) {
+					if (a.AttributeType.FullName == "System.Runtime.CompilerServices.CompilerGeneratedAttribute")
+						return true;
+				}
+			}
+			return false;
+		}
+		
+		public static bool IsCompilerGeneratedOrIsInCompilerGeneratedClass(this IMemberDefinition member)
+		{
+			if (member == null)
+				return false;
+			if (member.IsCompilerGenerated())
+				return true;
+			return IsCompilerGeneratedOrIsInCompilerGeneratedClass(member.DeclaringType);
+		}
+
+		public static TypeReference GetEnumUnderlyingType(this TypeDefinition type)
+		{
+			if (!type.IsEnum)
+				throw new ArgumentException("Type must be an enum", "type");
+
+			var fields = type.Fields;
+
+			for (int i = 0; i < fields.Count; i++)
+			{
+				var field = fields[i];
+				if (!field.IsStatic)
+					return field.FieldType;
+			}
+
+			throw new NotSupportedException();
+		}
+		
+		public static bool IsAnonymousType(this TypeReference type)
+		{
+			if (type == null)
+				return false;
+			if (string.IsNullOrEmpty(type.Namespace) && type.HasGeneratedName() && (type.Name.Contains("AnonType") || type.Name.Contains("AnonymousType"))) {
+				TypeDefinition td = type.Resolve();
+				return td != null && td.IsCompilerGenerated();
+			}
+			return false;
+		}
+
+		public static bool HasGeneratedName(this MemberReference member)
+		{
+			return member.Name.StartsWith("<", StringComparison.Ordinal);
+		}
+		
+		public static bool ContainsAnonymousType(this TypeReference type)
+		{
+			GenericInstanceType git = type as GenericInstanceType;
+			if (git != null) {
+				if (IsAnonymousType(git))
+					return true;
+				for (int i = 0; i < git.GenericArguments.Count; i++) {
+					if (git.GenericArguments[i].ContainsAnonymousType())
+						return true;
+				}
+				return false;
+			}
+			TypeSpecification typeSpec = type as TypeSpecification;
+			if (typeSpec != null)
+				return typeSpec.ElementType.ContainsAnonymousType();
+			else
+				return false;
+		}
+
+		public static string GetDefaultMemberName(this TypeDefinition type)
+		{
+			CustomAttribute attr;
+			return type.GetDefaultMemberName(out attr);
+		}
+
+		public static string GetDefaultMemberName(this TypeDefinition type, out CustomAttribute defaultMemberAttribute)
+		{
+			if (type.HasCustomAttributes)
+				foreach (CustomAttribute ca in type.CustomAttributes)
+					if (ca.Constructor.DeclaringType.Name == "DefaultMemberAttribute" && ca.Constructor.DeclaringType.Namespace == "System.Reflection"
+						&& ca.Constructor.FullName == @"System.Void System.Reflection.DefaultMemberAttribute::.ctor(System.String)") {
+						defaultMemberAttribute = ca;
+						return ca.ConstructorArguments[0].Value as string;
+					}
+			defaultMemberAttribute = null;
+			return null;
+		}
+
+		public static bool IsIndexer(this PropertyDefinition property)
+		{
+			CustomAttribute attr;
+			return property.IsIndexer(out attr);
+		}
+
+		public static bool IsIndexer(this PropertyDefinition property, out CustomAttribute defaultMemberAttribute)
+		{
+			defaultMemberAttribute = null;
+			if (property.HasParameters) {
+				var accessor = property.GetMethod ?? property.SetMethod;
+				PropertyDefinition basePropDef = property;
+				if (accessor.HasOverrides) {
+					// if the property is explicitly implementing an interface, look up the property in the interface:
+					MethodDefinition baseAccessor = accessor.Overrides.First().Resolve();
+					if (baseAccessor != null) {
+						foreach (PropertyDefinition baseProp in baseAccessor.DeclaringType.Properties) {
+							if (baseProp.GetMethod == baseAccessor || baseProp.SetMethod == baseAccessor) {
+								basePropDef = baseProp;
+								break;
+							}
+						}
+					} else
+						return false;
+				}
+				CustomAttribute attr;
+				var defaultMemberName = basePropDef.DeclaringType.GetDefaultMemberName(out attr);
+				if (defaultMemberName == basePropDef.Name) {
+					defaultMemberAttribute = attr;
+					return true;
+				}
+			}
+			return false;
+		}
+
+		public static bool IsDelegate(this TypeDefinition type)
+		{
+			if (type.BaseType != null && type.BaseType.Namespace == "System") {
+				if (type.BaseType.Name == "MulticastDelegate")
+					return true;
+				if (type.BaseType.Name == "Delegate" && type.Name != "MulticastDelegate")
+					return true;
+			}
+			return false;
+		}
+	}
+}