[cDAC]: Flush contract caches

src/native/managed/cdac/Microsoft.Diagnostics.DataContractReader.Abstractions/ContractRegistry.cs

@@ -104,4 +104,10 @@ public abstract class ContractRegistry
     public virtual IBuiltInCOM BuiltInCOM => GetContract<IBuiltInCOM>();
 
     public abstract TContract GetContract<TContract>() where TContract : IContract;
+
+    /// <summary>
+    /// Flush all cached data held by contracts in this registry.
+    /// Called when the target process state may have changed (e.g. on resume).
+    /// </summary>
+    public abstract void Flush();
 }

src/native/managed/cdac/Microsoft.Diagnostics.DataContractReader.Abstractions/Contracts/IContract.cs

@@ -8,4 +8,10 @@ namespace Microsoft.Diagnostics.DataContractReader.Contracts;
 public interface IContract
 {
     static virtual string Name => throw new NotImplementedException();
+
+    /// <summary>
+    /// Clear any cached data held by this contract.
+    /// Called when the target process state may have changed (e.g. on resume).
+    /// </summary>
+    void Flush() { }
 }

src/native/managed/cdac/Microsoft.Diagnostics.DataContractReader.Abstractions/Target.cs

@@ -289,4 +289,14 @@ public readonly record struct FieldInfo
     /// A cache of the contracts for the target process
     /// </summary>
     public abstract ContractRegistry Contracts { get; }
+
+    /// <summary>
+    /// Clear all cached data held by this target, including processed data and contract caches.
+    /// Called when the target process state may have changed (e.g. on resume).
+    /// </summary>
+    public void Flush()
+    {
+        ProcessedData.Clear();
+        Contracts.Flush();
+    }
 }

src/native/managed/cdac/Microsoft.Diagnostics.DataContractReader.Contracts/Contracts/EcmaMetadata_1.cs

@@ -15,6 +15,11 @@ internal sealed class EcmaMetadata_1(Target target) : IEcmaMetadata
 {
     private Dictionary<ModuleHandle, MetadataReaderProvider?> _metadata = new();
 
+    public void Flush()
+    {
+        _metadata.Clear();
+    }
+
     public TargetSpan GetReadOnlyMetadataAddress(ModuleHandle handle)
     {
         ILoader loader = target.Contracts.Loader;

src/native/managed/cdac/Microsoft.Diagnostics.DataContractReader.Contracts/Contracts/ExecutionManager/ExecutionManagerCore.cs

@@ -32,6 +32,11 @@ public ExecutionManagerCore(Target target, Data.RangeSectionMap topRangeSectionM
         _r2rJitManager = new ReadyToRunJitManager(_target);
     }
 
+    public void Flush()
+    {
+        _codeInfos.Clear();
+    }
+
     // Note, because of RelativeOffset, this code info is per code pointer, not per method
     private sealed class CodeBlock
     {

src/native/managed/cdac/Microsoft.Diagnostics.DataContractReader.Contracts/Contracts/ExecutionManager/ExecutionManager_1.cs

@@ -29,4 +29,5 @@ internal ExecutionManager_1(Target target, Data.RangeSectionMap topRangeSectionM
     public TargetNUInt GetRelativeOffset(CodeBlockHandle codeInfoHandle) => _executionManagerCore.GetRelativeOffset(codeInfoHandle);
     public List<ExceptionClauseInfo> GetExceptionClauses(CodeBlockHandle codeInfoHandle) => _executionManagerCore.GetExceptionClauses(codeInfoHandle);
     public JitManagerInfo GetEEJitManagerInfo() => _executionManagerCore.GetEEJitManagerInfo();
+    public void Flush() => _executionManagerCore.Flush();
 }

src/native/managed/cdac/Microsoft.Diagnostics.DataContractReader.Contracts/Contracts/ExecutionManager/ExecutionManager_2.cs

@@ -29,4 +29,5 @@ internal ExecutionManager_2(Target target, Data.RangeSectionMap topRangeSectionM
     public TargetNUInt GetRelativeOffset(CodeBlockHandle codeInfoHandle) => _executionManagerCore.GetRelativeOffset(codeInfoHandle);
     public List<ExceptionClauseInfo> GetExceptionClauses(CodeBlockHandle codeInfoHandle) => _executionManagerCore.GetExceptionClauses(codeInfoHandle);
     public JitManagerInfo GetEEJitManagerInfo() => _executionManagerCore.GetEEJitManagerInfo();
+    public void Flush() => _executionManagerCore.Flush();
 }

src/native/managed/cdac/Microsoft.Diagnostics.DataContractReader.Contracts/Contracts/RuntimeTypeSystem_1.cs

@@ -30,6 +30,14 @@ internal partial struct RuntimeTypeSystem_1 : IRuntimeTypeSystem
     private readonly Dictionary<TypeKey, TypeHandle> _typeHandles = new();
     private readonly Dictionary<TypeKeyByName, TypeHandle> _typeHandlesByName = new();
 
+    public void Flush()
+    {
+        _methodTables.Clear();
+        _methodDescs.Clear();
+        _typeHandles.Clear();
+        _typeHandlesByName.Clear();
+    }
+
     internal struct MethodTable
     {
         internal MethodTableFlags_1 Flags { get; }

src/native/managed/cdac/Microsoft.Diagnostics.DataContractReader.Contracts/Contracts/Signature/SignatureDecoder_1.cs

@@ -28,6 +28,12 @@ internal SignatureDecoder_1(Target target)
         _target = target;
     }
 
+    public void Flush()
+    {
+        _thProviders.Clear();
+        _mdhProviders.Clear();
+    }
+
     private SignatureTypeProvider<TypeHandle> GetTypeHandleProvider(ModuleHandle moduleHandle)
     {
         if (_thProviders.TryGetValue(moduleHandle, out SignatureTypeProvider<TypeHandle>? thProvider))

src/native/managed/cdac/Microsoft.Diagnostics.DataContractReader.Legacy/SOSDacImpl.IXCLRDataProcess.cs

@@ -20,7 +20,7 @@ public sealed unsafe partial class SOSDacImpl : IXCLRDataProcess, IXCLRDataProce
 {
     int IXCLRDataProcess.Flush()
     {
-        _target.ProcessedData.Clear();
+        _target.Flush();
 
         // As long as any part of cDAC falls back to the legacy DAC, we need to propagate the Flush call
         if (_legacyProcess is not null)

src/native/managed/cdac/Microsoft.Diagnostics.DataContractReader.Legacy/SOSDacImpl.cs

@@ -5785,7 +5785,15 @@ int ISOSDacInterface13.GetGCBookkeepingMemoryRegions(DacComNullableByRef<ISOSMem
     int ISOSDacInterface13.GetGCFreeRegions(DacComNullableByRef<ISOSMemoryEnum> ppEnum)
         => _legacyImpl13 is not null ? _legacyImpl13.GetGCFreeRegions(ppEnum) : HResults.E_NOTIMPL;
     int ISOSDacInterface13.LockedFlush()
-        => _legacyImpl13 is not null ? _legacyImpl13.LockedFlush() : HResults.E_NOTIMPL;
+    {
+        _target.Flush();
+
+        // As long as any part of cDAC falls back to the legacy DAC, we need to propagate the Flush call
+        if (_legacyImpl13 is not null)
+            return _legacyImpl13.LockedFlush();
+
+        return HResults.S_OK;
+    }
     #endregion ISOSDacInterface13
 
     #region ISOSDacInterface14

src/native/managed/cdac/Microsoft.Diagnostics.DataContractReader/CachingContractRegistry.cs

@@ -76,4 +76,12 @@ public override TContract GetContract<TContract>()
         // Contract was already registered by someone else
         return (TContract)_contracts[typeof(TContract)];
     }
+
+    public override void Flush()
+    {
+        foreach (IContract contract in _contracts.Values)
+        {
+            contract.Flush();
+        }
+    }
 }

src/native/managed/cdac/tests/TestPlaceholderTarget.cs

@@ -450,6 +450,8 @@ public override TContract GetContract<TContract>()
 
             throw new NotImplementedException($"Contract {typeof(TContract).Name} is not registered.");
         }
+
+        public override void Flush() { }
     }
 
 }