14150291621

Committed 29 Mar 2025 11:11PM UTC coverage: 34.811% (+0.08%) from 34.732%

Build # 14150291621

Build Type

Pull #436

github

Committed by

web-flow

Commit Message

Merge bf235906d into 734414756

Pull Request Pull Request #436: Improvements to method overrides

Run Details

1802 of 6468 branches covered (27.86%)

Branch coverage included in aggregate %.

23 of 23 new or added lines in 1 file covered. (100.0%)

23 existing lines in 1 file now uncovered.

4152 of 10636 relevant lines covered (39.04%)

161341.65 hits per line

Source File
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54.29

/Cpp2IL.Core/Model/Contexts/MethodAnalysisContext.cs

using System;
using System.Collections.Generic;
using System.Diagnostics.CodeAnalysis;
using System.Reflection;
using Cpp2IL.Core.Graphs;
using Cpp2IL.Core.ISIL;
using Cpp2IL.Core.Graphs.Processors;
using Cpp2IL.Core.Logging;
using Cpp2IL.Core.Utils;
using LibCpp2IL;
using LibCpp2IL.Metadata;
using StableNameDotNet.Providers;
using System.Linq;
using LibCpp2IL.Reflection;

namespace Cpp2IL.Core.Model.Contexts;

/// <summary>
/// Represents one method within the application. Can be analyzed to attempt to reconstruct the function body.
/// </summary>
public class MethodAnalysisContext : HasCustomAttributesAndName, IMethodInfoProvider
{
    /// <summary>
    /// The underlying metadata for the method.
    ///
    /// Nullable iff this is a subclass.
    /// </summary>
    public readonly Il2CppMethodDefinition? Definition;

    /// <summary>
    /// The analysis context for the declaring type of this method.
    /// </summary>
    public readonly TypeAnalysisContext? DeclaringType;

    /// <summary>
    /// The address of this method as defined in the underlying metadata.
    /// </summary>
    public virtual ulong UnderlyingPointer => Definition?.MethodPointer ?? throw new("Subclasses of MethodAnalysisContext should override UnderlyingPointer");

    public ulong Rva => UnderlyingPointer == 0 || LibCpp2IlMain.Binary == null ? 0 : LibCpp2IlMain.Binary.GetRva(UnderlyingPointer);

    /// <summary>
    /// The raw method body as machine code in the active instruction set.
    /// </summary>
    public Memory<byte> RawBytes => rawMethodBody ??= InitRawBytes();

    /// <summary>
    /// The first-stage-analyzed Instruction-Set-Independent Language Instructions.
    /// </summary>
    public List<InstructionSetIndependentInstruction>? ConvertedIsil;

    /// <summary>
    /// The control flow graph for this method, if one is built.
    /// </summary>
    public ISILControlFlowGraph? ControlFlowGraph;

    public List<ParameterAnalysisContext> Parameters = [];

    /// <summary>
    /// Does this method return void?
    /// </summary>
    public virtual bool IsVoid => (Definition?.ReturnType?.ToString() ?? throw new("Subclasses of MethodAnalysisContext should override IsVoid")) == "System.Void";

    public virtual bool IsStatic => Definition?.IsStatic ?? throw new("Subclasses of MethodAnalysisContext should override IsStatic");

    protected override int CustomAttributeIndex => Definition?.customAttributeIndex ?? throw new("Subclasses of MethodAnalysisContext should override CustomAttributeIndex if they have custom attributes");

    public override AssemblyAnalysisContext CustomAttributeAssembly => DeclaringType?.DeclaringAssembly ?? throw new("Subclasses of MethodAnalysisContext should override CustomAttributeAssembly if they have custom attributes");

    public override string DefaultName => Definition?.Name ?? throw new("Subclasses of MethodAnalysisContext should override DefaultName");

    public string FullName => DeclaringType == null ? Name : $"{DeclaringType.FullName}::{Name}";

    public string FullNameWithSignature => $"{ReturnTypeContext.FullName} {FullName}({string.Join(", ", Parameters.Select(p => p.HumanReadableSignature))})";

    public virtual MethodAttributes Attributes => Definition?.Attributes ?? throw new("Subclasses of MethodAnalysisContext should override Attributes");

    public TypeAnalysisContext? InjectedReturnType { get; set; }

    public int ParameterCount => Parameters.Count;

    public int GenericParameterCount => Definition?.GenericContainer?.genericParameterCount ?? 0;

    private ushort Slot => Definition?.slot ?? ushort.MaxValue;

    //TODO Support custom attributes on return types (v31 feature)
    public TypeAnalysisContext ReturnTypeContext => InjectedReturnType ?? DeclaringType!.DeclaringAssembly.ResolveIl2CppType(Definition!.RawReturnType!);
    
    protected Memory<byte>? rawMethodBody;

    public MethodAnalysisContext? BaseMethod => Overrides.FirstOrDefault(m => m.DeclaringType?.IsInterface is false);

    /// <summary>
    /// The set of methods which this method overrides.
    /// </summary>
    public virtual IEnumerable<MethodAnalysisContext> Overrides
    {
        get
        {
            if (Definition == null)
                return [];

            var declaringTypeDefinition = DeclaringType?.Definition;
            if (declaringTypeDefinition == null)
                return [];

            var vtable = declaringTypeDefinition.VTable;
            if (vtable == null)
                return [];

            return GetOverriddenMethods(declaringTypeDefinition, vtable);

            bool TryGetMethodForSlot(TypeAnalysisContext declaringType, int slot, [NotNullWhen(true)] out MethodAnalysisContext? method)
            {
                if (declaringType is GenericInstanceTypeAnalysisContext genericInstanceType)
                {
                    var genericMethod = genericInstanceType.GenericType.Methods.FirstOrDefault(m => m.Slot == slot);
                    if (genericMethod is not null)
                    {
                        method = new ConcreteGenericMethodAnalysisContext(genericMethod, genericInstanceType.GenericArguments.ToArray(), []);
                        return true;
                    }
                }
                else
                {
                    var baseMethod = declaringType.Methods.FirstOrDefault(m => m.Slot == slot);
                    if (baseMethod is not null)
                    {
                        method = baseMethod;
                        return true;
                    }
                }

                method = null;
                return false;
            }

            IEnumerable<MethodAnalysisContext> GetOverriddenMethods(Il2CppTypeDefinition declaringTypeDefinition, MetadataUsage?[] vtable)
            {
                for (var i = 0; i < vtable.Length; ++i)
                {
                    var vtableEntry = vtable[i];
                    if (vtableEntry is null or { Type: not MetadataUsageType.MethodDef })
                        continue;

                    if (vtableEntry.AsMethod() != Definition)
                        continue;

                    // Normal inheritance
                    var baseType = DeclaringType?.BaseType;
                    while (baseType is not null)
                    {
                        if (TryGetMethodForSlot(baseType, i, out var method))
                        {
                            yield return method;
                            break;
                        }
                        baseType = baseType.BaseType;
                    }

                    // Interface inheritance
                    foreach (var interfaceOffset in declaringTypeDefinition.InterfaceOffsets)
                    {
                        if (i >= interfaceOffset.offset)
                        {
                            var interfaceTypeContext = interfaceOffset.Type.ToContext(CustomAttributeAssembly);
                            if (interfaceTypeContext != null && TryGetMethodForSlot(interfaceTypeContext, i - interfaceOffset.offset, out var method))
                                yield return method;
                        }
                    }
                }
            }
        }
    }

    private static readonly List<IBlockProcessor> blockProcessors =
    [
        new MetadataProcessor(),
        new CallProcessor()
    ];

    public MethodAnalysisContext(Il2CppMethodDefinition? definition, TypeAnalysisContext parent) : base(definition?.token ?? 0, parent.AppContext)
    {
        DeclaringType = parent;
        Definition = definition;

        if (Definition != null)
        {
            InitCustomAttributeData();

            for (var i = 0; i < Definition.InternalParameterData!.Length; i++)
            {
                var parameterDefinition = Definition.InternalParameterData![i];
                Parameters.Add(new(parameterDefinition, i, this));
            }
        }
        else
            rawMethodBody = Array.Empty<byte>();
    }

    [MemberNotNull(nameof(rawMethodBody))]
    public void EnsureRawBytes()
    {
        rawMethodBody ??= InitRawBytes();
    }

    private Memory<byte> InitRawBytes()
    {
        //Some abstract methods (on interfaces, no less) apparently have a body? Unity doesn't support default interface methods so idk what's going on here.
        //E.g. UnityEngine.Purchasing.AppleCore.dll: UnityEngine.Purchasing.INativeAppleStore::SetUnityPurchasingCallback on among us (itch.io build)
        if (Definition != null && Definition.MethodPointer != 0 && !Definition.Attributes.HasFlag(MethodAttributes.Abstract))
        {
            var ret = AppContext.InstructionSet.GetRawBytesForMethod(this, false);

            if (ret.Length == 0)
            {
                Logger.VerboseNewline("\t\t\tUnexpectedly got 0-byte method body for " + this + $". Pointer was 0x{Definition.MethodPointer:X}", "MAC");
            }

            return ret;
        }
        else
            return Array.Empty<byte>();
    }

    protected MethodAnalysisContext(ApplicationAnalysisContext context) : base(0, context)
    {
        rawMethodBody = Array.Empty<byte>();
    }

    [MemberNotNull(nameof(ConvertedIsil))]
    public void Analyze()
    {
        if (ConvertedIsil != null)
            return;

        if (UnderlyingPointer == 0)
        {
            ConvertedIsil = [];
            return;
        }

        ConvertedIsil = AppContext.InstructionSet.GetIsilFromMethod(this);

        if (ConvertedIsil.Count == 0)
            return; //Nothing to do, empty function

        ControlFlowGraph = new ISILControlFlowGraph();
        ControlFlowGraph.Build(ConvertedIsil);

        // Post step to convert metadata usage. Ldstr Opcodes etc.
        foreach (var block in ControlFlowGraph.Blocks)
        {
            foreach (var converter in blockProcessors)
            {
                converter.Process(this, block);
            }
        }
    }

    public void ReleaseAnalysisData()
    {
        ConvertedIsil = null;
        ControlFlowGraph = null;
    }

    public override string ToString() => $"Method: {FullName}";

    #region StableNameDot implementation

    ITypeInfoProvider IMethodInfoProvider.ReturnType =>
        Definition!.RawReturnType!.ThisOrElementIsGenericParam()
            ? new GenericParameterTypeInfoProviderWrapper(Definition.RawReturnType!.GetGenericParamName())
            : TypeAnalysisContext.GetSndnProviderForType(AppContext, Definition!.RawReturnType);

    IEnumerable<IParameterInfoProvider> IMethodInfoProvider.ParameterInfoProviders => Parameters;

    string IMethodInfoProvider.MethodName => Name;

    MethodAttributes IMethodInfoProvider.MethodAttributes => Attributes;

    MethodSemantics IMethodInfoProvider.MethodSemantics
    {
        get
        {
            if (DeclaringType != null)
            {
                //This one is a bit trickier, as il2cpp doesn't use semantics.
                foreach (var prop in DeclaringType.Properties)
                {
                    if (prop.Getter == this)
                        return MethodSemantics.Getter;
                    if (prop.Setter == this)
                        return MethodSemantics.Setter;
                }

                foreach (var evt in DeclaringType.Events)
                {
                    if (evt.Adder == this)
                        return MethodSemantics.AddOn;
                    if (evt.Remover == this)
                        return MethodSemantics.RemoveOn;
                    if (evt.Invoker == this)
                        return MethodSemantics.Fire;
                }
            }

            return 0;
        }
    }

    #endregion
}

1	using System;
2	using System.Collections.Generic;
3	using System.Diagnostics.CodeAnalysis;
4	using System.Reflection;
5	using Cpp2IL.Core.Graphs;
6	using Cpp2IL.Core.ISIL;
7	using Cpp2IL.Core.Graphs.Processors;
8	using Cpp2IL.Core.Logging;
9	using Cpp2IL.Core.Utils;
10	using LibCpp2IL;
11	using LibCpp2IL.Metadata;
12	using StableNameDotNet.Providers;
13	using System.Linq;
14	using LibCpp2IL.Reflection;
15
16	namespace Cpp2IL.Core.Model.Contexts;
17
18	/// <summary>
19	/// Represents one method within the application. Can be analyzed to attempt to reconstruct the function body.
20	/// </summary>
21	public class MethodAnalysisContext : HasCustomAttributesAndName, IMethodInfoProvider
22	{
23	/// <summary>
24	/// The underlying metadata for the method.
25	///
26	/// Nullable iff this is a subclass.
27	/// </summary>
28	public readonly Il2CppMethodDefinition? Definition;
29
30	/// <summary>
31	/// The analysis context for the declaring type of this method.
32	/// </summary>
33	public readonly TypeAnalysisContext? DeclaringType;
34
35	/// <summary>
36	/// The address of this method as defined in the underlying metadata.
37	/// </summary>
38	public virtual ulong UnderlyingPointer => Definition?.MethodPointer ?? throw new("Subclasses of MethodAnalysisContext should override UnderlyingPointer");	694,548!
39
40	public ulong Rva => UnderlyingPointer == 0 \|\| LibCpp2IlMain.Binary == null ? 0 : LibCpp2IlMain.Binary.GetRva(UnderlyingPointer);	×
41
42	/// <summary>
43	/// The raw method body as machine code in the active instruction set.
44	/// </summary>
45	public Memory<byte> RawBytes => rawMethodBody ??= InitRawBytes();	×
46
47	/// <summary>
48	/// The first-stage-analyzed Instruction-Set-Independent Language Instructions.
49	/// </summary>
50	public List<InstructionSetIndependentInstruction>? ConvertedIsil;
51
52	/// <summary>
53	/// The control flow graph for this method, if one is built.
54	/// </summary>
55	public ISILControlFlowGraph? ControlFlowGraph;
56
57	public List<ParameterAnalysisContext> Parameters = [];	582,203✔
58
59	/// <summary>
60	/// Does this method return void?
61	/// </summary>
62	public virtual bool IsVoid => (Definition?.ReturnType?.ToString() ?? throw new("Subclasses of MethodAnalysisContext should override IsVoid")) == "System.Void";	×
63
64	public virtual bool IsStatic => Definition?.IsStatic ?? throw new("Subclasses of MethodAnalysisContext should override IsStatic");	87,355!
65
66	protected override int CustomAttributeIndex => Definition?.customAttributeIndex ?? throw new("Subclasses of MethodAnalysisContext should override CustomAttributeIndex if they have custom attributes");	278,496!
67
68	public override AssemblyAnalysisContext CustomAttributeAssembly => DeclaringType?.DeclaringAssembly ?? throw new("Subclasses of MethodAnalysisContext should override CustomAttributeAssembly if they have custom attributes");	436,488!
69
70	public override string DefaultName => Definition?.Name ?? throw new("Subclasses of MethodAnalysisContext should override DefaultName");	87,591!
71
72	public string FullName => DeclaringType == null ? Name : $"{DeclaringType.FullName}::{Name}";	28!
73
74	public string FullNameWithSignature => $"{ReturnTypeContext.FullName} {FullName}({string.Join(", ", Parameters.Select(p => p.HumanReadableSignature))})";	×
75
76	public virtual MethodAttributes Attributes => Definition?.Attributes ?? throw new("Subclasses of MethodAnalysisContext should override Attributes");	174,060!
77
78	public TypeAnalysisContext? InjectedReturnType { get; set; }	545,738✔
79
80	public int ParameterCount => Parameters.Count;	8✔
81
82	public int GenericParameterCount => Definition?.GenericContainer?.genericParameterCount ?? 0;	279,909!
83
84	private ushort Slot => Definition?.slot ?? ushort.MaxValue;	75,670!
85
86	//TODO Support custom attributes on return types (v31 feature)
87	public TypeAnalysisContext ReturnTypeContext => InjectedReturnType ?? DeclaringType!.DeclaringAssembly.ResolveIl2CppType(Definition!.RawReturnType!);	316,485✔
88
89	protected Memory<byte>? rawMethodBody;
90
91	public MethodAnalysisContext? BaseMethod => Overrides.FirstOrDefault(m => m.DeclaringType?.IsInterface is false);	6!
92
93	/// <summary>
94	/// The set of methods which this method overrides.
95	/// </summary>
96	public virtual IEnumerable<MethodAnalysisContext> Overrides
97	{
98	get
99	{
100	if (Definition == null)	18,034!
101	return [];	×
102
103	var declaringTypeDefinition = DeclaringType?.Definition;	18,034!
104	if (declaringTypeDefinition == null)	18,034!
105	return [];	×
106
107	var vtable = declaringTypeDefinition.VTable;	18,034✔
108	if (vtable == null)	18,034!
109	return [];	×
110
111	return GetOverriddenMethods(declaringTypeDefinition, vtable);	18,034✔
112
113	bool TryGetMethodForSlot(TypeAnalysisContext declaringType, int slot, [NotNullWhen(true)] out MethodAnalysisContext? method)
114	{
115	if (declaringType is GenericInstanceTypeAnalysisContext genericInstanceType)	13,515✔
116	{
117	var genericMethod = genericInstanceType.GenericType.Methods.FirstOrDefault(m => m.Slot == slot);	7,093✔
118	if (genericMethod is not null)	1,800✔
119	{
120	method = new ConcreteGenericMethodAnalysisContext(genericMethod, genericInstanceType.GenericArguments.ToArray(), []);	329✔
121	return true;	329✔
122	}
123	}
124	else
125	{
126	var baseMethod = declaringType.Methods.FirstOrDefault(m => m.Slot == slot);	82,092✔
127	if (baseMethod is not null)	11,715✔
128	{
129	method = baseMethod;	2,829✔
130	return true;	2,829✔
131	}
132	}
133
134	method = null;	10,357✔
135	return false;	10,357✔
136	}
137
138	IEnumerable<MethodAnalysisContext> GetOverriddenMethods(Il2CppTypeDefinition declaringTypeDefinition, MetadataUsage?[] vtable)
139	{
140	for (var i = 0; i < vtable.Length; ++i)	683,538✔
141	{
142	var vtableEntry = vtable[i];	323,736✔
143	if (vtableEntry is null or { Type: not MetadataUsageType.MethodDef })	323,736✔
144	continue;
145
146	if (vtableEntry.AsMethod() != Definition)	318,126✔
147	continue;
148
149	// Normal inheritance
150	var baseType = DeclaringType?.BaseType;	3,123!
151	while (baseType is not null)	7,849✔
152	{
153	if (TryGetMethodForSlot(baseType, i, out var method))	4,763✔
154	{
155	yield return method;	37✔
156	break;	36✔
157	}
158	baseType = baseType.BaseType;	4,726✔
159	}
160
161	// Interface inheritance
162	foreach (var interfaceOffset in declaringTypeDefinition.InterfaceOffsets)	34,546✔
163	{
164	if (i >= interfaceOffset.offset)	14,151✔
165	{
166	var interfaceTypeContext = interfaceOffset.Type.ToContext(CustomAttributeAssembly);	8,752✔
167	if (interfaceTypeContext != null && TryGetMethodForSlot(interfaceTypeContext, i - interfaceOffset.offset, out var method))	8,752✔
168	yield return method;	3,121✔
169	}
170	}
171	}
172	}	18,033✔
173	}
174	}
175
UNCOV 176	private static readonly List<IBlockProcessor> blockProcessors =	×
UNCOV 177	[	×
178	new MetadataProcessor(),	×
179	new CallProcessor()	×
180	];	×
181
182	public MethodAnalysisContext(Il2CppMethodDefinition? definition, TypeAnalysisContext parent) : base(definition?.token ?? 0, parent.AppContext)	582,203✔
183	{
184	DeclaringType = parent;	582,203✔
185	Definition = definition;	582,203✔
186
187	if (Definition != null)	582,203✔
188	{
189	InitCustomAttributeData();	352,950✔
190
191	for (var i = 0; i < Definition.InternalParameterData!.Length; i++)	1,519,920✔
192	{
193	var parameterDefinition = Definition.InternalParameterData![i];	407,010✔
194	Parameters.Add(new(parameterDefinition, i, this));	407,010✔
195	}
196	}
197	else
198	rawMethodBody = Array.Empty<byte>();	229,253✔
199	}	229,253✔
200
201	[MemberNotNull(nameof(rawMethodBody))]
202	public void EnsureRawBytes()
203	{
204	rawMethodBody ??= InitRawBytes();	352,950✔
205	}	352,950✔
206
207	private Memory<byte> InitRawBytes()
208	{
209	//Some abstract methods (on interfaces, no less) apparently have a body? Unity doesn't support default interface methods so idk what's going on here.
210	//E.g. UnityEngine.Purchasing.AppleCore.dll: UnityEngine.Purchasing.INativeAppleStore::SetUnityPurchasingCallback on among us (itch.io build)
211	if (Definition != null && Definition.MethodPointer != 0 && !Definition.Attributes.HasFlag(MethodAttributes.Abstract))	352,950✔
212	{
213	var ret = AppContext.InstructionSet.GetRawBytesForMethod(this, false);	341,598✔
214
215	if (ret.Length == 0)	341,598✔
216	{
217	Logger.VerboseNewline("\t\t\tUnexpectedly got 0-byte method body for " + this + $". Pointer was 0x{Definition.MethodPointer:X}", "MAC");	28!
218	}
219
220	return ret;	341,598✔
221	}
222	else
223	return Array.Empty<byte>();	11,352✔
224	}
225
UNCOV 226	protected MethodAnalysisContext(ApplicationAnalysisContext context) : base(0, context)	×
227	{
228	rawMethodBody = Array.Empty<byte>();	×
UNCOV 229	}	×
230
231	[MemberNotNull(nameof(ConvertedIsil))]
232	public void Analyze()
233	{
UNCOV 234	if (ConvertedIsil != null)	×
UNCOV 235	return;	×
236
237	if (UnderlyingPointer == 0)	×
238	{
239	ConvertedIsil = [];	×
UNCOV 240	return;	×
241	}
242
UNCOV 243	ConvertedIsil = AppContext.InstructionSet.GetIsilFromMethod(this);	×
244
245	if (ConvertedIsil.Count == 0)	×
UNCOV 246	return; //Nothing to do, empty function	×
247
248	ControlFlowGraph = new ISILControlFlowGraph();	×
UNCOV 249	ControlFlowGraph.Build(ConvertedIsil);	×
250
251	// Post step to convert metadata usage. Ldstr Opcodes etc.
UNCOV 252	foreach (var block in ControlFlowGraph.Blocks)	×
253	{
254	foreach (var converter in blockProcessors)	×
255	{
256	converter.Process(this, block);	×
257	}
258	}
UNCOV 259	}	×
260
261	public void ReleaseAnalysisData()
262	{
UNCOV 263	ConvertedIsil = null;	×
UNCOV 264	ControlFlowGraph = null;	×
265	}	×
266
267	public override string ToString() => $"Method: {FullName}";	28✔
268
269	#region StableNameDot implementation
270
271	ITypeInfoProvider IMethodInfoProvider.ReturnType =>
UNCOV 272	Definition!.RawReturnType!.ThisOrElementIsGenericParam()	×
UNCOV 273	? new GenericParameterTypeInfoProviderWrapper(Definition.RawReturnType!.GetGenericParamName())	×
274	: TypeAnalysisContext.GetSndnProviderForType(AppContext, Definition!.RawReturnType);	×
275
276	IEnumerable<IParameterInfoProvider> IMethodInfoProvider.ParameterInfoProviders => Parameters;	×
277
278	string IMethodInfoProvider.MethodName => Name;	×
279
280	MethodAttributes IMethodInfoProvider.MethodAttributes => Attributes;	×
281
282	MethodSemantics IMethodInfoProvider.MethodSemantics
283	{
284	get
285	{
UNCOV 286	if (DeclaringType != null)	×
287	{
288	//This one is a bit trickier, as il2cpp doesn't use semantics.
UNCOV 289	foreach (var prop in DeclaringType.Properties)	×
290	{
291	if (prop.Getter == this)	×
UNCOV 292	return MethodSemantics.Getter;	×
293	if (prop.Setter == this)	×
294	return MethodSemantics.Setter;	×
295	}
296
UNCOV 297	foreach (var evt in DeclaringType.Events)	×
298	{
299	if (evt.Adder == this)	×
UNCOV 300	return MethodSemantics.AddOn;	×
301	if (evt.Remover == this)	×
302	return MethodSemantics.RemoveOn;	×
303	if (evt.Invoker == this)	×
304	return MethodSemantics.Fire;	×
305	}
306	}
307
UNCOV 308	return 0;	×
UNCOV 309	}	×
310	}
311
312	#endregion
313	}

SamboyCoding / Cpp2IL / 14150291621

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