Implement ISOSDacInterface::GetLoaderAllocatorHeapNames and GetLoaderAllocatorHeaps in cDAC SOSDacImpl by Copilot · Pull Request #124818 · dotnet/runtime

Copilot · 2026-02-24T20:24:35Z

Description

Implements ISOSDacInterface13.GetLoaderAllocatorHeapNames and ISOSDacInterface13.GetLoaderAllocatorHeaps in the managed cDAC SOSDacImpl.cs, replacing the legacy DAC delegation stubs. Based on ClrDataAccess::GetLoaderAllocatorHeapNames and ClrDataAccess::GetLoaderAllocatorHeaps in request.cpp.

Native Data Descriptors

Added heap fields to cdac_data<LoaderAllocator> in loaderallocator.hpp: StaticsHeap, ExecutableHeap, FixupPrecodeHeap (#ifdef HAS_FIXUP_PRECODE), NewStubPrecodeHeap (#ifndef FEATURE_PORTABLE_ENTRYPOINTS), DynamicHelpersStubHeap (FEATURE_READYTORUN && FEATURE_STUBPRECODE_DYNAMIC_HELPERS), VirtualCallStubManager
Added new cdac_data<VirtualCallStubManager> in virtualcallstub.h: IndcellHeap (unconditional), CacheEntryHeap (#ifdef FEATURE_VIRTUAL_STUB_DISPATCH)
Added corresponding entries to datadescriptor.inc with matching feature guards
Added VirtualCallStubManager to DataType enum
Added #include "virtualcallstub.h" to datadescriptor.h so cdac_data<VirtualCallStubManager> is visible when datadescriptor.inc is compiled

Managed Data Classes

Updated Data/LoaderAllocator.cs with optional heap fields (FixupPrecodeHeap, NewStubPrecodeHeap, DynamicHelpersStubHeap as nullable) and always-present fields (StaticsHeap, ExecutableHeap, VirtualCallStubManager)
Created Data/VirtualCallStubManager.cs with IndcellHeap and optional CacheEntryHeap

ILoader Contract

Added single GetLoaderAllocatorHeaps(TargetPointer) method to ILoader interface returning IReadOnlyDictionary<string, TargetPointer> — dictionary keys are heap names, values are heap pointers
Implemented in Loader_1.cs with dynamic dictionary building based on data descriptor field presence via ContainsKey checks, matching the native #ifdef conditional compilation
Dictionary keys use nameof(Data.LoaderAllocator.X) and nameof(Data.VirtualCallStubManager.X) instead of hardcoded strings
Feature-conditional heaps (FixupPrecodeHeap, NewStubPrecodeHeap, DynamicHelpersStubHeap) are only included when the data descriptor field exists
VirtualCallStubManager heaps (IndcellHeap, CacheEntryHeap) are excluded entirely when VirtualCallStubManager is null

SOSDacImpl

GetLoaderAllocatorHeapNames: Queries global loader allocator via ILoader.GetLoaderAllocatorHeaps to get heap names from dictionary keys. Lazily initializes ANSI string pointers via Marshal.StringToHGlobalAnsi, cached on the instance along with the ordered name strings. Standard cDAC pattern with try/catch, S_FALSE when buffer is insufficient
GetLoaderAllocatorHeaps: Uses the cached canonical name ordering from GetLoaderAllocatorHeapNames to look up heap pointers by key via TryGetValue, defaulting to 0 for missing entries. This ensures names[i] always corresponds to heaps[i] regardless of dictionary enumeration order, matching the DAC's fixed-array ordering contract. Fills LoaderHeapKindNormal for all heaps
Both methods include #if DEBUG validation blocks that compare cDAC results against legacy DAC output — heap name strings and heap pointer/kind values are validated to match, following the pattern used by other cDAC APIs

Contract Documentation

Updated docs/design/datacontracts/Loader.md with:
- New GetLoaderAllocatorHeaps API in the contract API section
- New data descriptor fields for LoaderAllocator (StaticsHeap, ExecutableHeap, FixupPrecodeHeap, NewStubPrecodeHeap, DynamicHelpersStubHeap, VirtualCallStubManager) and new VirtualCallStubManager type (IndcellHeap, CacheEntryHeap) in the data descriptors table
- Pseudocode implementation showing feature-conditional dictionary building logic

Tests

8 test methods in LoaderTests.cs × 4 architectures = 32 new test cases
- GetLoaderAllocatorHeapNames: Count query, full name retrieval, insufficient buffer, null pNeeded
- GetLoaderAllocatorHeaps: Count query, full heap retrieval, insufficient buffer, null address
- Name-heap correspondence test verifying that names[i] matches the expected heap address at index i
All 900 cDAC tests pass

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

dotnet-policy-service · 2026-02-24T20:57:40Z

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max-charlamb · 2026-02-24T21:18:01Z

@copilot, try again

Copilot · 2026-02-24T21:29:19Z

@copilot, try again

Implementation reworked in commits up to 0554c43. Changes:

Feature-conditional heap names: GetLoaderAllocatorHeapNames in Loader_1.cs dynamically builds the names list by checking ContainsKey on the data descriptor fields - DynamicHelpersStubHeap is conditional on FEATURE_READYTORUN && FEATURE_STUBPRECODE_DYNAMIC_HELPERS, and CacheEntryHeap is conditional on FEATURE_VIRTUAL_STUB_DISPATCH, matching the native LoaderAllocatorLoaderHeapNames array.

GetLoaderAllocatorHeaps: Fully implemented in SOSDacImpl.cs, reading heap pointers through the ILoader contract. The contract reads from LoaderAllocator and VirtualCallStubManager data classes, handling null VcsManager by padding with TargetPointer.Null.

Native data descriptors: Added cdac_data<LoaderAllocator> fields (StaticsHeap, ExecutableHeap, FixupPrecodeHeap, NewStubPrecodeHeap, DynamicHelpersStubHeap, VirtualCallStubManager) and new cdac_data<VirtualCallStubManager> (IndcellHeap, CacheEntryHeap) in loaderallocator.hpp, virtualcallstub.h, and datadescriptor.inc.

Tests: 32 new test cases (8 test methods × 4 architectures) covering both methods. All 864 cDAC tests pass.

max-charlamb

@copilot , address feedback

...tive/managed/cdac/Microsoft.Diagnostics.DataContractReader.Abstractions/Contracts/ILoader.cs

max-charlamb

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...native/managed/cdac/Microsoft.Diagnostics.DataContractReader.Contracts/Contracts/Loader_1.cs

Copilot · 2026-02-24T22:05:53Z

@copilot , address feedback

Addressed all three review comments in e0e9cd5 — nameof for dict keys, conditional inclusion for FixupPrecodeHeap/NewStubPrecodeHeap, and no null-padding for VcsManager heaps. All 864 tests pass.

@copilot, try again

Addressed all three review comments in e0e9cd5 — nameof for dict keys, conditional inclusion for FixupPrecodeHeap/NewStubPrecodeHeap, and no null-padding for VcsManager heaps. All 864 tests pass.

max-charlamb · 2026-02-24T22:37:27Z

@copilot , please fix build break

Copilot · 2026-02-24T22:46:39Z

@copilot , please fix build break

Fixed in 3f63f2f. The issue was that datadescriptor.h did not include virtualcallstub.h, so cdac_data<VirtualCallStubManager> was not visible when datadescriptor.inc was compiled. Added #include "virtualcallstub.h" to datadescriptor.h.

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...tive/managed/cdac/Microsoft.Diagnostics.DataContractReader.Abstractions/Contracts/ILoader.cs

max-charlamb

@copilot , address feedback

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

Copilot · 2026-02-25T18:17:31Z

@copilot , address feedback

Addressed in 2c1ed8a. Both GetLoaderAllocatorHeapNames and GetLoaderAllocatorHeaps now validate actual names and heap pointer/kind values against the legacy DAC in the #if DEBUG blocks. All 900 tests pass.

Copilot

Pull request overview

This PR implements ISOSDacInterface13.GetLoaderAllocatorHeapNames and ISOSDacInterface13.GetLoaderAllocatorHeaps in the managed cDAC, replacing legacy DAC delegation stubs. The implementation adds native data descriptors for loader allocator heaps and VirtualCallStubManager heaps, creates corresponding managed data classes, extends the ILoader contract, and includes comprehensive tests.

Changes:

Added native data descriptors for LoaderAllocator heaps (StaticsHeap, ExecutableHeap, and feature-conditional heaps) and new VirtualCallStubManager type with heap fields
Implemented GetLoaderAllocatorHeaps in the ILoader contract returning a dictionary of heap names to pointers, with dynamic inclusion based on data descriptor field presence
Implemented SOSDacImpl methods to query heap names and addresses through the ILoader contract, with DEBUG validation against legacy DAC

Reviewed changes

Copilot reviewed 12 out of 12 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
src/coreclr/vm/loaderallocator.hpp	Added cdac_data fields for StaticsHeap, ExecutableHeap, and feature-conditional heap fields (FixupPrecodeHeap, NewStubPrecodeHeap, DynamicHelpersStubHeap, VirtualCallStubManager)
src/coreclr/vm/virtualcallstub.h	Created cdac_data specialization for VirtualCallStubManager with IndcellHeap and CacheEntryHeap fields
src/coreclr/vm/datadescriptor/datadescriptor.h	Added #include for virtualcallstub.h to expose VirtualCallStubManager data template
src/coreclr/vm/datadescriptor/datadescriptor.inc	Added LoaderAllocator heap fields and new VirtualCallStubManager type with matching feature guards
src/native/managed/cdac/Microsoft.Diagnostics.DataContractReader.Abstractions/DataType.cs	Added VirtualCallStubManager enum value
src/native/managed/cdac/Microsoft.Diagnostics.DataContractReader.Abstractions/Contracts/ILoader.cs	Added GetLoaderAllocatorHeaps method to ILoader interface
src/native/managed/cdac/Microsoft.Diagnostics.DataContractReader.Contracts/Data/LoaderAllocator.cs	Added StaticsHeap, ExecutableHeap, and nullable feature-conditional heap properties, plus VirtualCallStubManager pointer
src/native/managed/cdac/Microsoft.Diagnostics.DataContractReader.Contracts/Data/VirtualCallStubManager.cs	Created new data class with IndcellHeap and nullable CacheEntryHeap properties
src/native/managed/cdac/Microsoft.Diagnostics.DataContractReader.Contracts/Contracts/Loader_1.cs	Implemented GetLoaderAllocatorHeaps with dictionary building logic that conditionally includes heaps based on data descriptor field presence
src/native/managed/cdac/Microsoft.Diagnostics.DataContractReader.Legacy/SOSDacImpl.cs	Implemented GetLoaderAllocatorHeapNames and GetLoaderAllocatorHeaps with lazy initialization, caching, and DEBUG validation
src/native/managed/cdac/tests/LoaderTests.cs	Added 8 test methods covering count queries, full retrieval, insufficient buffers, and null parameters for both APIs
docs/design/datacontracts/Loader.md	Documented new API, data descriptor fields, and pseudocode implementation

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

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

Copilot · 2026-02-26T18:00:04Z

@copilot , address feedback

Addressed in e3279f1. Fixed the ordering issue by caching the name strings alongside ANSI pointers, then using that cached ordering in GetLoaderAllocatorHeaps to look up values by key — ensuring names[i] always corresponds to heaps[i].

Co-authored-by: max-charlamb <44248479+max-charlamb@users.noreply.github.com>

…dd missing using Co-authored-by: max-charlamb <44248479+max-charlamb@users.noreply.github.com>

…ps API Replace separate GetLoaderAllocatorHeapNames() and GetLoaderAllocatorHeaps(TargetPointer) with a single GetLoaderAllocatorHeaps(TargetPointer) returning IReadOnlyDictionary<string, TargetPointer>. SOSDacImpl.GetLoaderAllocatorHeapNames now queries the global loader allocator to get names from the dictionary. GetLoaderAllocatorHeaps iterates dictionary values. Tests updated to use dictionary-based mock and verify unordered name/address sets. Co-authored-by: max-charlamb <44248479+max-charlamb@users.noreply.github.com>

…tionary - Use nameof(Data.LoaderAllocator.X) instead of hardcoded strings for all dictionary keys in GetLoaderAllocatorHeaps - Make FixupPrecodeHeap and NewStubPrecodeHeap conditional on ContainsKey (exclude from dictionary when field absent from data descriptor) - Remove else branch that padded IndcellHeap/CacheEntryHeap with null when VirtualCallStubManager is null - only include them when VcsManager exists - All 864 cDAC tests pass Co-authored-by: max-charlamb <44248479+max-charlamb@users.noreply.github.com>

datadescriptor.h did not include virtualcallstub.h, so the cdac_data<VirtualCallStubManager> template specialization was not visible when datadescriptor.inc was compiled. This caused a build failure referencing cdac_data<VirtualCallStubManager>::IndcellHeap and cdac_data<VirtualCallStubManager>::CacheEntryHeap. Co-authored-by: max-charlamb <44248479+max-charlamb@users.noreply.github.com>

Add documentation for the new ILoader.GetLoaderAllocatorHeaps API, including: - New API in the contract API section - New data descriptor fields for LoaderAllocator (StaticsHeap, ExecutableHeap, FixupPrecodeHeap, NewStubPrecodeHeap, DynamicHelpersStubHeap, VirtualCallStubManager) and VirtualCallStubManager (IndcellHeap, CacheEntryHeap) in the data descriptors table - Pseudocode implementation showing feature-conditional dictionary building Co-authored-by: max-charlamb <44248479+max-charlamb@users.noreply.github.com>

…AllocatorHeaps Expand #if DEBUG validation blocks to compare actual name strings and heap pointer/kind values between cDAC and legacy DAC, following the pattern used by GetAssemblyList and GetMethodsWithProfilerModifiedIL. Co-authored-by: max-charlamb <44248479+max-charlamb@users.noreply.github.com>

… names[i] ↔ heaps[i] correspondence Co-authored-by: max-charlamb <44248479+max-charlamb@users.noreply.github.com>

Copilot AI assigned Copilot and max-charlamb Feb 24, 2026

Copilot started work on behalf of max-charlamb February 24, 2026 20:24 View session

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Copilot AI changed the title ~~[WIP] Implement GetLoaderAllocatorHeapNames in SOSDacImpl.cs~~ Implement ISOSDacInterface::GetLoaderAllocatorHeapNames in cDAC SOSDacImpl Feb 24, 2026

Copilot finished work on behalf of max-charlamb February 24, 2026 20:51

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Copilot AI changed the title ~~Implement ISOSDacInterface::GetLoaderAllocatorHeapNames in cDAC SOSDacImpl~~ Implement ISOSDacInterface::GetLoaderAllocatorHeapNames and GetLoaderAllocatorHeaps in cDAC SOSDacImpl Feb 24, 2026

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build-analysis bot mentioned this pull request Feb 25, 2026

[android][clr] No peer certificates when executing System.Net.Http.Functional.Tests on Android emulator #124526

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[FAIL] System.Net.Http.Functional.Tests.SocketsHttpHandler_HttpClientHandlerTest.LargeUriAndHeaders_Works #124487

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Copilot AI and others added 13 commits March 6, 2026 14:36

Initial plan

0471d01

Implement GetLoaderAllocatorHeapNames in SOSDacImpl and add unit tests

5acab0d

Co-authored-by: max-charlamb <44248479+max-charlamb@users.noreply.github.com>

Remove unused hrLocal variable in DEBUG block

39b29c6

Co-authored-by: max-charlamb <44248479+max-charlamb@users.noreply.github.com>

Changes before error encountered

80bf8bc

Co-authored-by: max-charlamb <44248479+max-charlamb@users.noreply.github.com>

Remove fragile try-catch for VirtualCallStubManager type lookup and a…

8efde78

…dd missing using Co-authored-by: max-charlamb <44248479+max-charlamb@users.noreply.github.com>

Fix ordering: use cached name ordering in GetLoaderAllocatorHeaps for…

4244072

… names[i] ↔ heaps[i] correspondence Co-authored-by: max-charlamb <44248479+max-charlamb@users.noreply.github.com>

fix ordering and memory leak

e1ff417

match DAC handling of heap names

0adbea4

max-charlamb force-pushed the copilot/implement-get-loader-allocator-heap-names branch from e4980cc to 0adbea4 Compare March 6, 2026 19:53

add a test to verify ordering

a9c0a13

max-charlamb merged commit a6a3b3d into main Mar 9, 2026
112 of 114 checks passed

max-charlamb deleted the copilot/implement-get-loader-allocator-heap-names branch March 9, 2026 20:03

dotnet-maestro bot mentioned this pull request Mar 10, 2026

[main] Source code updates from dotnet/runtime dotnet/dotnet#5345

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Description

Native Data Descriptors

Managed Data Classes

ILoader Contract

SOSDacImpl

Contract Documentation

Tests

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