[cDAC] Adding symbols and using heap dumps

src/libraries/System.Net.Http/tests/UnitTests/DiagnosticsHelperTest.cs

@@ -4,7 +4,6 @@
 using System.Linq;
 using System.Text;
 using System.Threading.Tasks;
-using Microsoft.Diagnostics.Runtime.Utilities;
 using Microsoft.DotNet.RemoteExecutor;
 using Xunit;
 

src/libraries/System.Runtime.InteropServices/tests/ComInterfaceGenerator.Tests/UnmanagedToManagedCustomMarshallingTests.cs

@@ -7,7 +7,6 @@
 using System.Runtime.InteropServices;
 using System.Runtime.InteropServices.Marshalling;
 using System.Threading;
-using Microsoft.Diagnostics.Runtime;
 using SharedTypes;
 using Xunit;
 using static ComInterfaceGenerator.Tests.UnmanagedToManagedCustomMarshallingTests;

src/libraries/System.Security.Cryptography/tests/X509Certificates/PublicKeyTests.cs

@@ -5,7 +5,6 @@
 using System.IO;
 using System.Security.Cryptography.SLHDsa.Tests;
 using System.Security.Cryptography.Tests;
-using Microsoft.Diagnostics.Runtime.Interop;
 using Test.Cryptography;
 using Xunit;
 

src/native/managed/cdac/tests/DumpTests/AsyncContinuationDumpTests.cs

@@ -16,7 +16,6 @@ namespace Microsoft.Diagnostics.DataContractReader.DumpTests;
 public class AsyncContinuationDumpTests : DumpTestBase
 {
     protected override string DebuggeeName => "AsyncContinuation";
-    protected override string DumpType => "full";
 
     [ConditionalTheory]
     [MemberData(nameof(TestConfigurations))]

src/native/managed/cdac/tests/DumpTests/CCWDumpTests.cs

@@ -17,7 +17,6 @@ namespace Microsoft.Diagnostics.DataContractReader.DumpTests;
 public class CCWDumpTests : DumpTestBase
 {
     protected override string DebuggeeName => "CCW";
-    protected override string DumpType => "full";
 
     /// <summary>
     /// Enumerates all strong GC handles from the dump, dereferences each one to get

src/native/managed/cdac/tests/DumpTests/ClrMdDumpHost.cs

@@ -2,6 +2,9 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 
 using System;
+using System.Collections.Generic;
+using System.Reflection.PortableExecutable;
+using System.IO;
 using Microsoft.Diagnostics.Runtime;
 
 namespace Microsoft.Diagnostics.DataContractReader.DumpTests;
@@ -20,22 +23,30 @@ internal sealed class ClrMdDumpHost : IDisposable
     };
 
     private readonly DataTarget _dataTarget;
+    private readonly string[] _searchPaths;
 
     public string DumpPath { get; }
 
-    private ClrMdDumpHost(string dumpPath, DataTarget dataTarget)
+    private ClrMdDumpHost(string dumpPath, DataTarget dataTarget, string[] searchPaths)
     {
         DumpPath = dumpPath;
         _dataTarget = dataTarget;
+        _searchPaths = searchPaths;
     }
 
     /// <summary>
     /// Open a crash dump and prepare it for cDAC analysis.
     /// </summary>
-    public static ClrMdDumpHost Open(string dumpPath)
+    /// <param name="dumpPath">Path to the crash dump file.</param>
+    /// <param name="additionalSymbolPaths">
+    /// Local directories to search for symbol files (e.g., System.Private.CoreLib,
+    /// debuggee DLLs).
+    /// </param>
+    public static ClrMdDumpHost Open(string dumpPath, List<string> additionalSymbolPaths)
     {
         DataTarget dataTarget = DataTarget.LoadDump(dumpPath);
-        return new ClrMdDumpHost(dumpPath, dataTarget);
+
+        return new ClrMdDumpHost(dumpPath, dataTarget, additionalSymbolPaths.ToArray());
     }
 
     /// <summary>
@@ -45,7 +56,45 @@ public static ClrMdDumpHost Open(string dumpPath)
     public int ReadFromTarget(ulong address, Span<byte> buffer)
     {
         int bytesRead = _dataTarget.DataReader.Read(address, buffer);
-        return bytesRead == buffer.Length ? 0 : -1;
+        if (bytesRead == buffer.Length)
+            return 0; // success
+
+        // If we couldn't read the full buffer, maybe it's in a PE image
+        ModuleInfo? info = GetModuleForAddress(address);
+        if (info is null || info.FileName is null)
+        {
+            return -1;
+        }
+
+        string? foundFile = FindFileOnDisk(info.FileName);
+        if (foundFile is null)
+        {
+            return -1;
+        }
+
+        using FileStream fs = File.OpenRead(foundFile);
+        using PEReader peReader = new PEReader(fs);
+
+        int filled = bytesRead;
+        ulong current = address + (ulong)bytesRead;
+        while (filled < buffer.Length)
+        {
+            PEMemoryBlock block = peReader.GetSectionData((int)(current - info.ImageBase));
+            if (block.Length == 0)
+            {
+                return -1;
+            }
+
+            int toCopy = Math.Min(block.Length, buffer.Length - filled);
+            unsafe
+            {
+                new ReadOnlySpan<byte>(block.Pointer, toCopy).CopyTo(buffer.Slice(filled));
+            }
+            filled += toCopy;
+            current += (ulong)toCopy;
+        }
+
+        return 0;
     }
 
     /// <summary>
@@ -57,6 +106,16 @@ public int GetThreadContext(uint threadId, uint contextFlags, Span<byte> buffer)
         return _dataTarget.DataReader.GetThreadContext(threadId, contextFlags, buffer) ? 0 : -1;
     }
 
+    private ModuleInfo? GetModuleForAddress(ulong address)
+    {
+        foreach (ModuleInfo module in _dataTarget.DataReader.EnumerateModules())
+        {
+            if (address >= module.ImageBase && address < module.ImageBase + (ulong)module.ImageSize)
+                return module;
+        }
+        return null;
+    }
+
     /// <summary>
     /// Locate the DotNetRuntimeContractDescriptor symbol address in the dump.
     /// Uses ClrMD's built-in export resolution which handles PE, ELF, and Mach-O formats.
@@ -93,6 +152,24 @@ public ulong FindContractDescriptorAddress()
         throw new InvalidOperationException("Could not find DotNetRuntimeContractDescriptor export in any runtime module in the dump.");
     }
 
+    private string? FindFileOnDisk(string modulePath)
+    {
+        // for local runs
+        if (File.Exists(modulePath))
+            return modulePath;
+        int lastSep = Math.Max(modulePath.LastIndexOf('/'), modulePath.LastIndexOf('\\'));
+        string fileName = lastSep >= 0 ? modulePath[(lastSep + 1)..] : modulePath;
+
+        foreach (string searchPath in _searchPaths)
+        {
+            string candidate = Path.Combine(searchPath, fileName);
+            if (File.Exists(candidate))
+                return candidate;
+        }
+
+        return null;
+    }
+
     private static bool IsRuntimeModule(string fileName)
     {
         foreach (string name in s_runtimeModuleNames)

src/native/managed/cdac/tests/DumpTests/ComWrappersDumpTests.cs

@@ -17,7 +17,6 @@ namespace Microsoft.Diagnostics.DataContractReader.DumpTests;
 public class ComWrappersDumpTests : DumpTestBase
 {
     protected override string DebuggeeName => "ComWrappers";
-    protected override string DumpType => "full";
 
     [ConditionalTheory]
     [MemberData(nameof(TestConfigurations))]

src/native/managed/cdac/tests/DumpTests/DacDbi/DacDbiCCWDumpTests.cs

@@ -17,8 +17,6 @@ namespace Microsoft.Diagnostics.DataContractReader.DumpTests;
 public class DacDbiCCWDumpTests : DumpTestBase
 {
     protected override string DebuggeeName => "CCW";
-    protected override string DumpType => "full";
-
     private DacDbiImpl CreateDacDbi() => new DacDbiImpl(Target, legacyObj: null);
 
     private (TargetPointer Ccw, TargetPointer InterfacePointer) FindBuiltInComCcwWithInterface()

src/native/managed/cdac/tests/DumpTests/DacDbi/DacDbiComWrappersDumpTests.cs

@@ -16,8 +16,6 @@ namespace Microsoft.Diagnostics.DataContractReader.DumpTests;
 public class DacDbiComWrappersDumpTests : DumpTestBase
 {
     protected override string DebuggeeName => "ComWrappers";
-    protected override string DumpType => "full";
-
     private DacDbiImpl CreateDacDbi() => new DacDbiImpl(Target, legacyObj: null);
 
     [ConditionalTheory]

src/native/managed/cdac/tests/DumpTests/DacDbi/DacDbiLoaderDumpTests.cs

@@ -15,8 +15,6 @@ namespace Microsoft.Diagnostics.DataContractReader.DumpTests;
 public class DacDbiLoaderDumpTests : DumpTestBase
 {
     protected override string DebuggeeName => "MultiModule";
-    protected override string DumpType => "full";
-
     private DacDbiImpl CreateDacDbi() => new DacDbiImpl(Target, legacyObj: null);
 
     private IEnumerable<ModuleHandle> GetAllModules()

src/native/managed/cdac/tests/DumpTests/DacDbi/DacDbiRCWDumpTests.cs

@@ -15,8 +15,6 @@ namespace Microsoft.Diagnostics.DataContractReader.DumpTests;
 public class DacDbiRCWDumpTests : DumpTestBase
 {
     protected override string DebuggeeName => "RCW";
-    protected override string DumpType => "full";
-
     private DacDbiImpl CreateDacDbi() => new DacDbiImpl(Target, legacyObj: null);
 
     [ConditionalTheory]

src/native/managed/cdac/tests/DumpTests/Debuggees/AsyncContinuation/AsyncContinuation.csproj

@@ -4,7 +4,6 @@
     <Features>$(Features);runtime-async=on</Features>
     <EnablePreviewFeatures>true</EnablePreviewFeatures>
     <NoWarn>$(NoWarn);CA2007;CA2252</NoWarn>
-    <!-- Full dump needed so that module metadata is available for type lookup -->
-    <DumpTypes>Full</DumpTypes>
+    <DumpTypes>Heap</DumpTypes>
   </PropertyGroup>
 </Project>

src/native/managed/cdac/tests/DumpTests/Debuggees/CCW/CCW.csproj

@@ -1,6 +1,6 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
-    <DumpTypes>Full</DumpTypes>
+    <DumpTypes>Heap</DumpTypes>
     <WindowsOnly>true</WindowsOnly>
   </PropertyGroup>
 </Project>

src/native/managed/cdac/tests/DumpTests/Debuggees/ComWrappers/ComWrappers.csproj

@@ -1,5 +1,5 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
-    <DumpTypes>Full</DumpTypes>
+    <DumpTypes>Heap</DumpTypes>
   </PropertyGroup>
 </Project>

src/native/managed/cdac/tests/DumpTests/Debuggees/ExceptionHandlingInfo/ExceptionHandlingInfo.csproj

@@ -1,6 +1,6 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
-    <DumpTypes>Full</DumpTypes>
+    <DumpTypes>Heap</DumpTypes>
     <R2RModes>R2R;Jit</R2RModes>
   </PropertyGroup>
 </Project>

src/native/managed/cdac/tests/DumpTests/Debuggees/LocalVariables/LocalVariables.csproj

@@ -1,6 +1,6 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
-    <DumpTypes>Full</DumpTypes>
+    <DumpTypes>Heap</DumpTypes>
     <!-- local variables don't display correctly in R2R dumps -->
     <R2RModes>Jit</R2RModes>
     <AllowUnsafeBlocks>true</AllowUnsafeBlocks>

src/native/managed/cdac/tests/DumpTests/Debuggees/MultiModule/MultiModule.csproj

@@ -1,5 +1,5 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
-    <DumpTypes>Full</DumpTypes>
+    <DumpTypes>Heap</DumpTypes>
   </PropertyGroup>
 </Project>

src/native/managed/cdac/tests/DumpTests/Debuggees/RCW/RCW.csproj

@@ -2,7 +2,7 @@
   <PropertyGroup>
     <!-- This debuggee is intentionally Windows-only (COM interop). -->
     <NoWarn>$(NoWarn);CA1416</NoWarn>
-    <DumpTypes>Full</DumpTypes>
+    <DumpTypes>Heap</DumpTypes>
     <WindowsOnly>true</WindowsOnly>
   </PropertyGroup>
 </Project>

src/native/managed/cdac/tests/DumpTests/Debuggees/RCWCleanupList/RCWCleanupList.csproj

@@ -2,7 +2,7 @@
   <PropertyGroup>
     <!-- This debuggee is intentionally Windows-only (COM interop). -->
     <NoWarn>$(NoWarn);CA1416</NoWarn>
-    <DumpTypes>Full</DumpTypes>
+    <DumpTypes>Heap</DumpTypes>
     <WindowsOnly>true</WindowsOnly>
   </PropertyGroup>
 </Project>

src/native/managed/cdac/tests/DumpTests/Debuggees/StackWalk/StackWalk.csproj

@@ -1,6 +1,6 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
-    <DumpTypes>Full</DumpTypes>
+    <DumpTypes>Heap</DumpTypes>
     <R2RModes>R2R;Jit</R2RModes>
   </PropertyGroup>
 </Project>

src/native/managed/cdac/tests/DumpTests/Debuggees/SyncBlock/SyncBlock.csproj

@@ -1,5 +1,5 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
-    <DumpTypes>Full</DumpTypes>
+    <DumpTypes>Heap</DumpTypes>
   </PropertyGroup>
 </Project>

src/native/managed/cdac/tests/DumpTests/DumpTestBase.cs

@@ -105,7 +105,7 @@ protected void InitializeDumpTest(TestConfiguration config, string debuggeeName,
             throw new SkipTestException($"No {config.R2RMode} dump for {debuggeeName}: {dumpPath}");
         }
 
-        _host = ClrMdDumpHost.Open(dumpPath);
+        _host = ClrMdDumpHost.Open(dumpPath, GetSymbolPaths(debuggeeName, versionDir));
         ulong contractDescriptor = _host.FindContractDescriptorAddress();
 
         bool created = ContractDescriptorTarget.TryCreate(
@@ -245,6 +245,30 @@ private static bool IsVersionSkipped(string version)
         return false;
     }
 
+    /// <summary>
+    /// Collects local symbol paths for ClrMD to resolve modules in the dump.
+    /// Checks <c>symbols/</c> directories in the helix payload (Helix and xplat dumps)
+    /// </summary>
+    private static List<string> GetSymbolPaths(string debuggeeName, string versionDir)
+    {
+        List<string> paths = [];
+
+        // Symbols directory in the dump tree (populated by Helix commands before tarring)
+        string symbolsDir = Path.Combine(versionDir, "symbols");
+        if (Directory.Exists(symbolsDir))
+        {
+            string runtimeSymbols = Path.Combine(symbolsDir, "runtime");
+            if (Directory.Exists(runtimeSymbols))
+                paths.Add(runtimeSymbols);
+
+            string debuggeeSymbols = Path.Combine(symbolsDir, "debuggees", debuggeeName);
+            if (Directory.Exists(debuggeeSymbols))
+                paths.Add(debuggeeSymbols);
+        }
+
+        return paths;
+    }
+
     private static string? FindRepoRoot()
     {
         string? dir = AppContext.BaseDirectory;

src/native/managed/cdac/tests/DumpTests/EcmaMetadataDumpTests.cs

@@ -14,7 +14,6 @@ namespace Microsoft.Diagnostics.DataContractReader.DumpTests;
 public class EcmaMetadataDumpTests : DumpTestBase
 {
     protected override string DebuggeeName => "MultiModule";
-    protected override string DumpType => "full";
 
     [ConditionalTheory]
     [MemberData(nameof(TestConfigurations))]

src/native/managed/cdac/tests/DumpTests/ExceptionHandlingInfoDumpTests.cs

@@ -20,7 +20,6 @@ namespace Microsoft.Diagnostics.DataContractReader.DumpTests;
 public class ExceptionHandlingInfoDumpTests : DumpTestBase
 {
     protected override string DebuggeeName => "ExceptionHandlingInfo";
-    protected override string DumpType => "full";
 
     /// <summary>
     /// Finds the CodeBlockHandle for the CrashInExceptionHandler method by walking

src/native/managed/cdac/tests/DumpTests/ISOSDacInterface13Tests.cs

@@ -15,7 +15,6 @@ namespace Microsoft.Diagnostics.DataContractReader.DumpTests;
 public class ISOSDacInterface13Tests : DumpTestBase
 {
     protected override string DebuggeeName => "MultiModule";
-    protected override string DumpType => "full";
 
     [ConditionalTheory]
     [MemberData(nameof(TestConfigurations))]

src/native/managed/cdac/tests/DumpTests/IXCLRDataAppDomainDumpTests.cs

@@ -16,7 +16,6 @@ namespace Microsoft.Diagnostics.DataContractReader.DumpTests;
 public unsafe class IXCLRDataAppDomainDumpTests : DumpTestBase
 {
     protected override string DebuggeeName => "StackWalk";
-    protected override string DumpType => "full";
 
     // ========== GetName ==========
 

src/native/managed/cdac/tests/DumpTests/IXCLRDataFrameDumpTests.cs

@@ -16,7 +16,6 @@ namespace Microsoft.Diagnostics.DataContractReader.DumpTests;
 public unsafe class IXCLRDataFrameDumpTests : DumpTestBase
 {
     protected override string DebuggeeName => "StackWalk";
-    protected override string DumpType => "full";
 
     // ========== GetContext ==========
 

src/native/managed/cdac/tests/DumpTests/IXCLRDataMethodDefinitionDumpTests.cs

@@ -19,7 +19,6 @@ namespace Microsoft.Diagnostics.DataContractReader.DumpTests;
 public unsafe class IXCLRDataMethodDefinitionDumpTests : DumpTestBase
 {
     protected override string DebuggeeName => "StackWalk";
-    protected override string DumpType => "full";
 
     // ========== GetName ==========
 

src/native/managed/cdac/tests/DumpTests/IXCLRDataValueDumpTests.cs

@@ -19,7 +19,6 @@ namespace Microsoft.Diagnostics.DataContractReader.DumpTests;
 public unsafe class IXCLRDataValueDumpTests : DumpTestBase
 {
     protected override string DebuggeeName => "LocalVariables";
-    protected override string DumpType => "full";
 
     // ========== GetSize ==========