Fix that method resolution would consider all function-pointers to be…

… the same (jbevain#885)
Unity-Technologies · Nov 30, 2022 · 0d2cf2e · 0d2cf2e
1 parent 55142e2
commit 0d2cf2e
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Showing 3 changed files with 115 additions and 1 deletion.
diff --git a/Mono.Cecil/MetadataResolver.cs b/Mono.Cecil/MetadataResolver.cs
@@ -319,6 +319,35 @@ static bool AreSame (TypeSpecification a, TypeSpecification b)
 			if (a.IsArray)
 				return AreSame ((ArrayType) a, (ArrayType) b);
 
+			if (a.IsFunctionPointer)
+				return AreSame ((FunctionPointerType) a, (FunctionPointerType) b);
+
+			return true;
+		}
+
+		static bool AreSame (FunctionPointerType a, FunctionPointerType b)
+		{
+			if (a.HasThis != b.HasThis)
+				return false;
+
+			if (a.CallingConvention != b.CallingConvention)
+				return false;
+
+			if (!AreSame (a.ReturnType, b.ReturnType))
+				return false;
+
+			if (a.ContainsGenericParameter != b.ContainsGenericParameter)
+				return false;
+
+			if (a.HasParameters != b.HasParameters)
+				return false;
+
+			if (!a.HasParameters)
+				return true;
+
+			if (!AreSame (a.Parameters, b.Parameters))
+				return false;
+
 			return true;
 		}
 

diff --git a/Test/Mono.Cecil.Tests/MethodTests.cs b/Test/Mono.Cecil.Tests/MethodTests.cs
@@ -3,7 +3,7 @@
 
 using Mono.Cecil;
 using Mono.Cecil.Metadata;
-
+using Mono.Collections.Generic;
 using NUnit.Framework;
 
 namespace Mono.Cecil.Tests {
@@ -219,5 +219,65 @@ public void ReturnParameterMethod ()
 			Assert.IsNotNull (method);
 			Assert.AreEqual (method, method.MethodReturnType.Parameter.Method);
 		}
+
+		[Test]
+		public void InstanceAndStaticMethodComparison ()
+		{
+			TestIL ("others.il", module => {
+				var others = module.GetType ("Others");
+				var instance_method = others.Methods.Single (m => m.Name == "SameMethodNameInstanceStatic" && m.HasThis);
+				var static_method_reference = new MethodReference ("SameMethodNameInstanceStatic", instance_method.ReturnType, others)
+					{
+						HasThis = false
+					};
+
+				Assert.AreNotEqual(instance_method, static_method_reference.Resolve ());
+			});
+		}
+
+		[Test]
+		public void FunctionPointerArgumentOverload ()
+		{
+			TestIL ("others.il", module => {
+				var others = module.GetType ("Others");
+				var overloaded_methods = others.Methods.Where (m => m.Name == "OverloadedWithFpArg").ToArray ();
+				// Manually create the function-pointer type so `AreSame` won't exit early due to reference equality
+				var overloaded_method_int_reference = new MethodReference ("OverloadedWithFpArg", module.TypeSystem.Void, others)
+				{
+					HasThis = false,
+					Parameters = { new ParameterDefinition ("X", ParameterAttributes.None, new FunctionPointerType () {
+						HasThis = false,
+						ReturnType = module.TypeSystem.Int32,
+						Parameters = { new ParameterDefinition (module.TypeSystem.Int32) }
+					}) }
+				};
+
+				var overloaded_method_long_reference = new MethodReference ("OverloadedWithFpArg", module.TypeSystem.Void, others)
+				{
+					HasThis = false,
+					Parameters = { new ParameterDefinition ("X", ParameterAttributes.None, new FunctionPointerType () {
+						HasThis = false,
+						ReturnType = module.TypeSystem.Int32,
+						Parameters = { new ParameterDefinition (module.TypeSystem.Int64) }
+					}) }
+				};
+
+				var overloaded_method_cdecl_reference = new MethodReference ("OverloadedWithFpArg", module.TypeSystem.Void, others)
+				{
+					HasThis = false,
+					Parameters = { new ParameterDefinition ("X", ParameterAttributes.None, new FunctionPointerType () {
+						CallingConvention = MethodCallingConvention.C,
+						HasThis = false,
+						ReturnType = module.TypeSystem.Int32,
+						Parameters = { new ParameterDefinition (module.TypeSystem.Int32) }
+					}) }
+				};
+
+
+				Assert.AreEqual (overloaded_methods[0], overloaded_method_int_reference.Resolve ());
+				Assert.AreEqual (overloaded_methods[1], overloaded_method_long_reference.Resolve ());
+				Assert.AreEqual (overloaded_methods[2], overloaded_method_cdecl_reference.Resolve ());
+			});
+		}
 	}
 }
diff --git a/Test/Resources/il/others.il b/Test/Resources/il/others.il
@@ -78,4 +78,29 @@
 		.other instance void Others::dang_Handler (class [mscorlib]System.EventHandler)
 		.other instance void Others::fang_Handler (class [mscorlib]System.EventHandler)
 	}
+
+	.method public static void OverloadedWithFpArg(method int32 *(int32) X) cil managed
+	{
+	    ret
+	}
+
+	.method public static void OverloadedWithFpArg(method int32 *(int64) X) cil managed
+	{
+	    ret
+	}
+
+	.method public static void OverloadedWithFpArg(method unmanaged cdecl int32 *(int32) X) cil managed
+	{
+	    ret
+	}
+
+	.method public instance void  SameMethodNameInstanceStatic() cil managed
+	{
+		ret
+	}
+
+	.method public static void  SameMethodNameInstanceStatic() cil managed
+	{
+		ret
+	} // end of static method MethodNameTests::MethodName
 }