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Move shared WASM logic to base writer - #131778

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Move shared WASM logic to base writer#131778
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There should be no behavioral changes from this PR, purely a refactor.

  • Move shared WebAssembly section mapping, ordering, and construction into WasmObjectWriter.
  • Move shared symbol/index-space, signature/funclet, typed-section row, stub, and symbol-table orchestration into the base writer.
  • Add a virtual data-section factory so WebCilObjectWriter can continue creating embedded WebcilSection instances, while the NativeAOT writer will use different section types.
  • Keep WebCIL-specific logic code in WebCilObjectWriter.
  • Include defined Table and Memory sections in standard WebAssembly emission order for future derived writers.

This preserves current WebCIL behavior while leaving the generic writer implementation ready to be shared with a second WebAssembly object writer.

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Pull request overview

This PR refactors the WebAssembly object writer stack by extracting shared section creation/mapping, symbol/index-space management, and emission-order orchestration into a new WasmObjectWriter base class, while keeping WebCIL-specific behavior in WebCilObjectWriter.

Changes:

  • Introduces WasmObjectWriter as the shared base implementation for WASM section construction, symbol management, and emission ordering.
  • Updates WebCilObjectWriter to delegate shared behaviors to the base writer and provide a WebCIL-specific data-section factory.
  • Adjusts WASM section interfaces/implementation details and updates the ReadyToRun project to compile the new base writer.

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 3 comments.

FileDescription
src/coreclr/tools/Common/Compiler/ObjectWriter/WebCilObjectWriter.csMoves shared WASM writer logic to the base class and adds an override factory for WebCIL data sections; retains WebCIL-specific import/export/global/layout behavior.
src/coreclr/tools/Common/Compiler/ObjectWriter/WasmObjectWriter.csAdds new shared base writer encapsulating section typing/mapping, symbol/index-space management, and section emission order.
src/coreclr/tools/Common/Compiler/ObjectWriter/Wasm/WasmSection.csMakes WASM emission/section interfaces explicitly internal and removes redundant bool initialization.
src/coreclr/tools/aot/ILCompiler.ReadyToRun/ILCompiler.ReadyToRun.csprojAdds the new base writer to compilation inputs (but currently duplicates the WebCIL writer include).

Comment threadsrc/coreclr/tools/aot/ILCompiler.ReadyToRun/ILCompiler.ReadyToRun.csproj
Comment threadsrc/coreclr/tools/Common/Compiler/ObjectWriter/WebCilObjectWriter.cs
Comment threadsrc/coreclr/tools/Common/Compiler/ObjectWriter/WasmObjectWriter.cs Outdated
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Pull request overview

Copilot reviewed 3 out of 3 changed files in this pull request and generated no new comments.

Suppressed comments (2)

src/coreclr/tools/Common/Compiler/ObjectWriter/WebCilObjectWriter.cs:905

  • These global index constants duplicate WasmGlobalImports and can silently drift out of sync with the canonical definitions (and the WasmGlobalImports remarks explicitly call out keeping CreateDefaultGlobalImports() in sync). Prefer referencing WasmGlobalImports.* here rather than hardcoding the numeric values again.
 internal const int StackPointerGlobalIndex = 0;
internal const int ImageBaseGlobalIndex = 1;
internal const int TableBaseGlobalIndex = 2;
internal const int AsyncContinuationGlobalIndex = 3;

src/coreclr/tools/Common/Compiler/ObjectWriter/WasmObjectWriter.cs:329

  • Typo in comment: "maintability" -> "maintainability".
 // TODO-Wasm: for maintability, we should try and push some of this into the dependency graph when we do more stub generation.

jkoritzinsky
jkoritzinsky reviewed Aug 17, 2026
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Comment threadsrc/coreclr/tools/Common/Compiler/ObjectWriter/WasmObjectWriter.cs
CopilotAI review requested due to automatic review settings August 18, 2026 17:56
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Base automatically changed from wasm-webcil-object-writer to mainAugust 18, 2026 17:59
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Review details

Suppressed comments (1)

src/coreclr/tools/Common/Compiler/ObjectWriter/WebCilObjectWriter.cs:905

  • These global index constants are now duplicated in both WasmGlobalImports and WebCilObjectWriter. Since WasmGlobalImports explicitly documents that the indices must stay in sync with CreateDefaultGlobalImports() and the host loader, keeping a single source of truth avoids accidental divergence in future edits.
 internal const int StackPointerGlobalIndex = 0;
internal const int ImageBaseGlobalIndex = 1;
internal const int TableBaseGlobalIndex = 2;
internal const int AsyncContinuationGlobalIndex = 3;
  • Files reviewed: 3/3 changed files
  • Comments generated: 0 new
  • Review effort level: Lite

CopilotAI review requested due to automatic review settings August 18, 2026 20:12
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Pull request overview

Copilot reviewed 3 out of 3 changed files in this pull request and generated no new comments.

Suppressed comments (2)

src/coreclr/tools/Common/Compiler/ObjectWriter/WebCilObjectWriter.cs:905

  • These global import indices are duplicated as raw constants here, but there is already an authoritative definition in WasmGlobalImports (with remarks about keeping CreateDefaultGlobalImports() in sync). Duplicating the numbers increases drift risk if the import list or host loader changes. Prefer forwarding to WasmGlobalImports.* so there’s a single source of truth.
 internal const int StackPointerGlobalIndex = 0;
internal const int ImageBaseGlobalIndex = 1;
internal const int TableBaseGlobalIndex = 2;
internal const int AsyncContinuationGlobalIndex = 3;

src/coreclr/tools/Common/Compiler/ObjectWriter/WasmObjectWriter.cs:75

  • WasmObjectWriter uses LINQ to build SectionEmitOrder (Where/Select/ToArray). In this repo’s core-runtime/tooling code, maintainers generally avoid LINQ in low-level compiler/AOT code to reduce allocations and keep dependencies minimal (core-runtime.instructions.md:17). Consider replacing this with a simple loop and removing the System.Linq dependency.
 _sectionEmitOrder ??= _sectionOrder
.Where(_sections.Contains)
.Select(_sections.GetSectionIndex)
.ToArray();

adamperlin
adamperlin approved these changes Aug 19, 2026
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This looks good to me overall!

@jtschuster

jtschuster commented Aug 19, 2026•
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/ba-g failure looks like #131925

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jtschuster merged commit adcf9c3 into mainAug 19, 2026
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@jkoritzinskyjkoritzinskyjkoritzinsky approved these changes
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Move shared WASM logic to base writer by jtschuster · Pull Request #131778 · dotnet/runtime · GitHub
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Move shared WASM logic to base writer - #131778
Merged
jtschuster merged 1 commit into
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wasm-writer-shared-implementation
Aug 19, 2026
Merged
Move shared WASM logic to base writer#131778
jtschuster merged 1 commit into
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There should be no behavioral changes from this PR, purely a refactor.
  • Move shared WebAssembly section mapping, ordering, and construction into WasmObjectWriter.
  • Move shared symbol/index-space, signature/funclet, typed-section row, stub, and symbol-table orchestration into the base writer.
  • Add a virtual data-section factory so WebCilObjectWriter can continue creating embedded WebcilSection instances, while the NativeAOT writer will use different section types.
  • Keep WebCIL-specific logic code in WebCilObjectWriter.
  • Include defined Table and Memory sections in standard WebAssembly emission order for future derived writers.
This preserves current WebCIL behavior while leaving the generic writer implementation ready to be shared with a second WebAssembly object writer.
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Pull request overview
This PR refactors the WebAssembly object writer stack by extracting shared section creation/mapping, symbol/index-space management, and emission-order orchestration into a new WasmObjectWriter base class, while keeping WebCIL-specific behavior in WebCilObjectWriter.
Changes:
  • Introduces WasmObjectWriter as the shared base implementation for WASM section construction, symbol management, and emission ordering.
  • Updates WebCilObjectWriter to delegate shared behaviors to the base writer and provide a WebCIL-specific data-section factory.
  • Adjusts WASM section interfaces/implementation details and updates the ReadyToRun project to compile the new base writer.
Reviewed changes
Copilot reviewed 4 out of 4 changed files in this pull request and generated 3 comments.
FileDescription
src/coreclr/tools/Common/Compiler/ObjectWriter/WebCilObjectWriter.csMoves shared WASM writer logic to the base class and adds an override factory for WebCIL data sections; retains WebCIL-specific import/export/global/layout behavior.
src/coreclr/tools/Common/Compiler/ObjectWriter/WasmObjectWriter.csAdds new shared base writer encapsulating section typing/mapping, symbol/index-space management, and section emission order.
src/coreclr/tools/Common/Compiler/ObjectWriter/Wasm/WasmSection.csMakes WASM emission/section interfaces explicitly internal and removes redundant bool initialization.
src/coreclr/tools/aot/ILCompiler.ReadyToRun/ILCompiler.ReadyToRun.csprojAdds the new base writer to compilation inputs (but currently duplicates the WebCIL writer include).
Comment threadsrc/coreclr/tools/aot/ILCompiler.ReadyToRun/ILCompiler.ReadyToRun.csproj
Comment threadsrc/coreclr/tools/Common/Compiler/ObjectWriter/WebCilObjectWriter.cs
Comment threadsrc/coreclr/tools/Common/Compiler/ObjectWriter/WasmObjectWriter.cs
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Pull request overview
Copilot reviewed 3 out of 3 changed files in this pull request and generated no new comments.
Suppressed comments (2)
src/coreclr/tools/Common/Compiler/ObjectWriter/WebCilObjectWriter.cs:905
  • These global index constants duplicate WasmGlobalImports and can silently drift out of sync with the canonical definitions (and the WasmGlobalImports remarks explicitly call out keeping CreateDefaultGlobalImports() in sync). Prefer referencing WasmGlobalImports.* here rather than hardcoding the numeric values again.
 internal const int StackPointerGlobalIndex = 0;
internal const int ImageBaseGlobalIndex = 1;
internal const int TableBaseGlobalIndex = 2;
internal const int AsyncContinuationGlobalIndex = 3;

src/coreclr/tools/Common/Compiler/ObjectWriter/WasmObjectWriter.cs:329
  • Typo in comment: "maintability" -> "maintainability".
 // TODO-Wasm: for maintability, we should try and push some of this into the dependency graph when we do more stub generation.

jkoritzinsky
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reviewed
Aug 17, 2026
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Comment threadsrc/coreclr/tools/Common/Compiler/ObjectWriter/WasmObjectWriter.cs
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Suppressed comments (1)
src/coreclr/tools/Common/Compiler/ObjectWriter/WebCilObjectWriter.cs:905
  • These global index constants are now duplicated in both WasmGlobalImports and WebCilObjectWriter. Since WasmGlobalImports explicitly documents that the indices must stay in sync with CreateDefaultGlobalImports() and the host loader, keeping a single source of truth avoids accidental divergence in future edits.
 internal const int StackPointerGlobalIndex = 0;
internal const int ImageBaseGlobalIndex = 1;
internal const int TableBaseGlobalIndex = 2;
internal const int AsyncContinuationGlobalIndex = 3;

  • Files reviewed: 3/3 changed files
  • Comments generated: 0 new
  • Review effort level: Lite
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Pull request overview
Copilot reviewed 3 out of 3 changed files in this pull request and generated no new comments.
Suppressed comments (2)
src/coreclr/tools/Common/Compiler/ObjectWriter/WebCilObjectWriter.cs:905
  • These global import indices are duplicated as raw constants here, but there is already an authoritative definition in WasmGlobalImports (with remarks about keeping CreateDefaultGlobalImports() in sync). Duplicating the numbers increases drift risk if the import list or host loader changes. Prefer forwarding to WasmGlobalImports.* so there’s a single source of truth.
 internal const int StackPointerGlobalIndex = 0;
internal const int ImageBaseGlobalIndex = 1;
internal const int TableBaseGlobalIndex = 2;
internal const int AsyncContinuationGlobalIndex = 3;

src/coreclr/tools/Common/Compiler/ObjectWriter/WasmObjectWriter.cs:75
  • WasmObjectWriter uses LINQ to build SectionEmitOrder (Where/Select/ToArray). In this repo’s core-runtime/tooling code, maintainers generally avoid LINQ in low-level compiler/AOT code to reduce allocations and keep dependencies minimal (core-runtime.instructions.md:17). Consider replacing this with a simple loop and removing the System.Linq dependency.
 _sectionEmitOrder ??= _sectionOrder
.Where(_sections.Contains)
.Select(_sections.GetSectionIndex)
.ToArray();

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This looks good to me overall!
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/ba-g failure looks like #131925
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@jkoritzinskyjkoritzinskyjkoritzinsky approved these changes
@adamperlinadamperlinadamperlin approved these changes
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Move shared WASM logic to base writer by jtschuster · Pull Request #131778 · dotnet/runtime · GitHub
Skip to content
Move shared WASM logic to base writer - #131778
Merged
jtschuster merged 1 commit into
mainfrom 
wasm-writer-shared-implementation
Aug 19, 2026
Merged
Move shared WASM logic to base writer#131778
jtschuster merged 1 commit into
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There should be no behavioral changes from this PR, purely a refactor.
  • Move shared WebAssembly section mapping, ordering, and construction into WasmObjectWriter.
  • Move shared symbol/index-space, signature/funclet, typed-section row, stub, and symbol-table orchestration into the base writer.
  • Add a virtual data-section factory so WebCilObjectWriter can continue creating embedded WebcilSection instances, while the NativeAOT writer will use different section types.
  • Keep WebCIL-specific logic code in WebCilObjectWriter.
  • Include defined Table and Memory sections in standard WebAssembly emission order for future derived writers.
This preserves current WebCIL behavior while leaving the generic writer implementation ready to be shared with a second WebAssembly object writer.
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Pull request overview
This PR refactors the WebAssembly object writer stack by extracting shared section creation/mapping, symbol/index-space management, and emission-order orchestration into a new WasmObjectWriter base class, while keeping WebCIL-specific behavior in WebCilObjectWriter.
Changes:
  • Introduces WasmObjectWriter as the shared base implementation for WASM section construction, symbol management, and emission ordering.
  • Updates WebCilObjectWriter to delegate shared behaviors to the base writer and provide a WebCIL-specific data-section factory.
  • Adjusts WASM section interfaces/implementation details and updates the ReadyToRun project to compile the new base writer.
Reviewed changes
Copilot reviewed 4 out of 4 changed files in this pull request and generated 3 comments.
FileDescription
src/coreclr/tools/Common/Compiler/ObjectWriter/WebCilObjectWriter.csMoves shared WASM writer logic to the base class and adds an override factory for WebCIL data sections; retains WebCIL-specific import/export/global/layout behavior.
src/coreclr/tools/Common/Compiler/ObjectWriter/WasmObjectWriter.csAdds new shared base writer encapsulating section typing/mapping, symbol/index-space management, and section emission order.
src/coreclr/tools/Common/Compiler/ObjectWriter/Wasm/WasmSection.csMakes WASM emission/section interfaces explicitly internal and removes redundant bool initialization.
src/coreclr/tools/aot/ILCompiler.ReadyToRun/ILCompiler.ReadyToRun.csprojAdds the new base writer to compilation inputs (but currently duplicates the WebCIL writer include).
Comment threadsrc/coreclr/tools/aot/ILCompiler.ReadyToRun/ILCompiler.ReadyToRun.csproj
Comment threadsrc/coreclr/tools/Common/Compiler/ObjectWriter/WebCilObjectWriter.cs
Comment threadsrc/coreclr/tools/Common/Compiler/ObjectWriter/WasmObjectWriter.cs
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Pull request overview
Copilot reviewed 3 out of 3 changed files in this pull request and generated no new comments.
Suppressed comments (2)
src/coreclr/tools/Common/Compiler/ObjectWriter/WebCilObjectWriter.cs:905
  • These global index constants duplicate WasmGlobalImports and can silently drift out of sync with the canonical definitions (and the WasmGlobalImports remarks explicitly call out keeping CreateDefaultGlobalImports() in sync). Prefer referencing WasmGlobalImports.* here rather than hardcoding the numeric values again.
 internal const int StackPointerGlobalIndex = 0;
internal const int ImageBaseGlobalIndex = 1;
internal const int TableBaseGlobalIndex = 2;
internal const int AsyncContinuationGlobalIndex = 3;

src/coreclr/tools/Common/Compiler/ObjectWriter/WasmObjectWriter.cs:329
  • Typo in comment: "maintability" -> "maintainability".
 // TODO-Wasm: for maintability, we should try and push some of this into the dependency graph when we do more stub generation.

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Comment threadsrc/coreclr/tools/Common/Compiler/ObjectWriter/WasmObjectWriter.cs
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Suppressed comments (1)
src/coreclr/tools/Common/Compiler/ObjectWriter/WebCilObjectWriter.cs:905
  • These global index constants are now duplicated in both WasmGlobalImports and WebCilObjectWriter. Since WasmGlobalImports explicitly documents that the indices must stay in sync with CreateDefaultGlobalImports() and the host loader, keeping a single source of truth avoids accidental divergence in future edits.
 internal const int StackPointerGlobalIndex = 0;
internal const int ImageBaseGlobalIndex = 1;
internal const int TableBaseGlobalIndex = 2;
internal const int AsyncContinuationGlobalIndex = 3;

  • Files reviewed: 3/3 changed files
  • Comments generated: 0 new
  • Review effort level: Lite
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Pull request overview
Copilot reviewed 3 out of 3 changed files in this pull request and generated no new comments.
Suppressed comments (2)
src/coreclr/tools/Common/Compiler/ObjectWriter/WebCilObjectWriter.cs:905
  • These global import indices are duplicated as raw constants here, but there is already an authoritative definition in WasmGlobalImports (with remarks about keeping CreateDefaultGlobalImports() in sync). Duplicating the numbers increases drift risk if the import list or host loader changes. Prefer forwarding to WasmGlobalImports.* so there’s a single source of truth.
 internal const int StackPointerGlobalIndex = 0;
internal const int ImageBaseGlobalIndex = 1;
internal const int TableBaseGlobalIndex = 2;
internal const int AsyncContinuationGlobalIndex = 3;

src/coreclr/tools/Common/Compiler/ObjectWriter/WasmObjectWriter.cs:75
  • WasmObjectWriter uses LINQ to build SectionEmitOrder (Where/Select/ToArray). In this repo’s core-runtime/tooling code, maintainers generally avoid LINQ in low-level compiler/AOT code to reduce allocations and keep dependencies minimal (core-runtime.instructions.md:17). Consider replacing this with a simple loop and removing the System.Linq dependency.
 _sectionEmitOrder ??= _sectionOrder
.Where(_sections.Contains)
.Select(_sections.GetSectionIndex)
.ToArray();

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This looks good to me overall!
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/ba-g failure looks like #131925
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@jkoritzinskyjkoritzinskyjkoritzinsky approved these changes
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, 'i');
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Move shared WASM logic to base writer by jtschuster · Pull Request #131778 · dotnet/runtime · GitHub
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Move shared WASM logic to base writer - #131778
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There should be no behavioral changes from this PR, purely a refactor.
  • Move shared WebAssembly section mapping, ordering, and construction into WasmObjectWriter.
  • Move shared symbol/index-space, signature/funclet, typed-section row, stub, and symbol-table orchestration into the base writer.
  • Add a virtual data-section factory so WebCilObjectWriter can continue creating embedded WebcilSection instances, while the NativeAOT writer will use different section types.
  • Keep WebCIL-specific logic code in WebCilObjectWriter.
  • Include defined Table and Memory sections in standard WebAssembly emission order for future derived writers.
This preserves current WebCIL behavior while leaving the generic writer implementation ready to be shared with a second WebAssembly object writer.
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Pull request overview
This PR refactors the WebAssembly object writer stack by extracting shared section creation/mapping, symbol/index-space management, and emission-order orchestration into a new WasmObjectWriter base class, while keeping WebCIL-specific behavior in WebCilObjectWriter.
Changes:
  • Introduces WasmObjectWriter as the shared base implementation for WASM section construction, symbol management, and emission ordering.
  • Updates WebCilObjectWriter to delegate shared behaviors to the base writer and provide a WebCIL-specific data-section factory.
  • Adjusts WASM section interfaces/implementation details and updates the ReadyToRun project to compile the new base writer.
Reviewed changes
Copilot reviewed 4 out of 4 changed files in this pull request and generated 3 comments.
FileDescription
src/coreclr/tools/Common/Compiler/ObjectWriter/WebCilObjectWriter.csMoves shared WASM writer logic to the base class and adds an override factory for WebCIL data sections; retains WebCIL-specific import/export/global/layout behavior.
src/coreclr/tools/Common/Compiler/ObjectWriter/WasmObjectWriter.csAdds new shared base writer encapsulating section typing/mapping, symbol/index-space management, and section emission order.
src/coreclr/tools/Common/Compiler/ObjectWriter/Wasm/WasmSection.csMakes WASM emission/section interfaces explicitly internal and removes redundant bool initialization.
src/coreclr/tools/aot/ILCompiler.ReadyToRun/ILCompiler.ReadyToRun.csprojAdds the new base writer to compilation inputs (but currently duplicates the WebCIL writer include).
Comment threadsrc/coreclr/tools/aot/ILCompiler.ReadyToRun/ILCompiler.ReadyToRun.csproj
Comment threadsrc/coreclr/tools/Common/Compiler/ObjectWriter/WebCilObjectWriter.cs
Comment threadsrc/coreclr/tools/Common/Compiler/ObjectWriter/WasmObjectWriter.cs
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Pull request overview
Copilot reviewed 3 out of 3 changed files in this pull request and generated no new comments.
Suppressed comments (2)
src/coreclr/tools/Common/Compiler/ObjectWriter/WebCilObjectWriter.cs:905
  • These global index constants duplicate WasmGlobalImports and can silently drift out of sync with the canonical definitions (and the WasmGlobalImports remarks explicitly call out keeping CreateDefaultGlobalImports() in sync). Prefer referencing WasmGlobalImports.* here rather than hardcoding the numeric values again.
 internal const int StackPointerGlobalIndex = 0;
internal const int ImageBaseGlobalIndex = 1;
internal const int TableBaseGlobalIndex = 2;
internal const int AsyncContinuationGlobalIndex = 3;

src/coreclr/tools/Common/Compiler/ObjectWriter/WasmObjectWriter.cs:329
  • Typo in comment: "maintability" -> "maintainability".
 // TODO-Wasm: for maintability, we should try and push some of this into the dependency graph when we do more stub generation.

jkoritzinsky
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Aug 17, 2026
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Comment threadsrc/coreclr/tools/Common/Compiler/ObjectWriter/WasmObjectWriter.cs
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Review details
Suppressed comments (1)
src/coreclr/tools/Common/Compiler/ObjectWriter/WebCilObjectWriter.cs:905
  • These global index constants are now duplicated in both WasmGlobalImports and WebCilObjectWriter. Since WasmGlobalImports explicitly documents that the indices must stay in sync with CreateDefaultGlobalImports() and the host loader, keeping a single source of truth avoids accidental divergence in future edits.
 internal const int StackPointerGlobalIndex = 0;
internal const int ImageBaseGlobalIndex = 1;
internal const int TableBaseGlobalIndex = 2;
internal const int AsyncContinuationGlobalIndex = 3;

  • Files reviewed: 3/3 changed files
  • Comments generated: 0 new
  • Review effort level: Lite
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Pull request overview
Copilot reviewed 3 out of 3 changed files in this pull request and generated no new comments.
Suppressed comments (2)
src/coreclr/tools/Common/Compiler/ObjectWriter/WebCilObjectWriter.cs:905
  • These global import indices are duplicated as raw constants here, but there is already an authoritative definition in WasmGlobalImports (with remarks about keeping CreateDefaultGlobalImports() in sync). Duplicating the numbers increases drift risk if the import list or host loader changes. Prefer forwarding to WasmGlobalImports.* so there’s a single source of truth.
 internal const int StackPointerGlobalIndex = 0;
internal const int ImageBaseGlobalIndex = 1;
internal const int TableBaseGlobalIndex = 2;
internal const int AsyncContinuationGlobalIndex = 3;

src/coreclr/tools/Common/Compiler/ObjectWriter/WasmObjectWriter.cs:75
  • WasmObjectWriter uses LINQ to build SectionEmitOrder (Where/Select/ToArray). In this repo’s core-runtime/tooling code, maintainers generally avoid LINQ in low-level compiler/AOT code to reduce allocations and keep dependencies minimal (core-runtime.instructions.md:17). Consider replacing this with a simple loop and removing the System.Linq dependency.
 _sectionEmitOrder ??= _sectionOrder
.Where(_sections.Contains)
.Select(_sections.GetSectionIndex)
.ToArray();

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This looks good to me overall!
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/ba-g failure looks like #131925
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@jkoritzinskyjkoritzinskyjkoritzinsky approved these changes
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, 'i');
if (__m === '*' || __re.test(location.href)) {
// Strip utm_, fbclid, gclid, etc. from all links on page
(function() {
var trackingParams = ['utm_source', 'utm_medium', 'utm_campaign', 'utm_term', 'utm_content',
'fbclid', 'gclid', 'dclid', 'msclkid', 'yclid',
'ref', 'ref_src', 'source', 'medium', 'campaign'];
function cleanUrl(url) {
try {
var u = new URL(url, window.location.origin);
var changed = false;
trackingParams.forEach(function(p) {
if (u.searchParams.has(p)) {
u.searchParams.delete(p);
changed = true;
}
});
return changed ? u.toString() : url;
} catch (e) {
return url;
}
}
function cleanLinks() {
document.querySelectorAll('a[href]').forEach(function(a) {
var clean = cleanUrl(a.href);
if (clean !== a.href) a.href = clean;
});
}
cleanLinks();
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mutations.forEach(function(m) {
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if (node.nodeType === 1) {
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if (clean !== a.href) a.href = clean;
});
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});
observer.observe(document.body, { childList: true, subtree: true });
})();
}
} catch(__e) { console.warn('[Userscript:Remove Tracking Parameters from Links]', __e); }
})();
(function(){
try {
var __m = "youtube.com";
var __re = new RegExp('^' + "youtube\\.com" + '
Move shared WASM logic to base writer by jtschuster · Pull Request #131778 · dotnet/runtime · GitHub
Skip to content
Move shared WASM logic to base writer - #131778
Merged
jtschuster merged 1 commit into
mainfrom 
wasm-writer-shared-implementation
Aug 19, 2026
Merged
Move shared WASM logic to base writer#131778
jtschuster merged 1 commit into
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There should be no behavioral changes from this PR, purely a refactor.
  • Move shared WebAssembly section mapping, ordering, and construction into WasmObjectWriter.
  • Move shared symbol/index-space, signature/funclet, typed-section row, stub, and symbol-table orchestration into the base writer.
  • Add a virtual data-section factory so WebCilObjectWriter can continue creating embedded WebcilSection instances, while the NativeAOT writer will use different section types.
  • Keep WebCIL-specific logic code in WebCilObjectWriter.
  • Include defined Table and Memory sections in standard WebAssembly emission order for future derived writers.
This preserves current WebCIL behavior while leaving the generic writer implementation ready to be shared with a second WebAssembly object writer.
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Pull request overview
This PR refactors the WebAssembly object writer stack by extracting shared section creation/mapping, symbol/index-space management, and emission-order orchestration into a new WasmObjectWriter base class, while keeping WebCIL-specific behavior in WebCilObjectWriter.
Changes:
  • Introduces WasmObjectWriter as the shared base implementation for WASM section construction, symbol management, and emission ordering.
  • Updates WebCilObjectWriter to delegate shared behaviors to the base writer and provide a WebCIL-specific data-section factory.
  • Adjusts WASM section interfaces/implementation details and updates the ReadyToRun project to compile the new base writer.
Reviewed changes
Copilot reviewed 4 out of 4 changed files in this pull request and generated 3 comments.
FileDescription
src/coreclr/tools/Common/Compiler/ObjectWriter/WebCilObjectWriter.csMoves shared WASM writer logic to the base class and adds an override factory for WebCIL data sections; retains WebCIL-specific import/export/global/layout behavior.
src/coreclr/tools/Common/Compiler/ObjectWriter/WasmObjectWriter.csAdds new shared base writer encapsulating section typing/mapping, symbol/index-space management, and section emission order.
src/coreclr/tools/Common/Compiler/ObjectWriter/Wasm/WasmSection.csMakes WASM emission/section interfaces explicitly internal and removes redundant bool initialization.
src/coreclr/tools/aot/ILCompiler.ReadyToRun/ILCompiler.ReadyToRun.csprojAdds the new base writer to compilation inputs (but currently duplicates the WebCIL writer include).
Comment threadsrc/coreclr/tools/aot/ILCompiler.ReadyToRun/ILCompiler.ReadyToRun.csproj
Comment threadsrc/coreclr/tools/Common/Compiler/ObjectWriter/WebCilObjectWriter.cs
Comment threadsrc/coreclr/tools/Common/Compiler/ObjectWriter/WasmObjectWriter.cs
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Pull request overview
Copilot reviewed 3 out of 3 changed files in this pull request and generated no new comments.
Suppressed comments (2)
src/coreclr/tools/Common/Compiler/ObjectWriter/WebCilObjectWriter.cs:905
  • These global index constants duplicate WasmGlobalImports and can silently drift out of sync with the canonical definitions (and the WasmGlobalImports remarks explicitly call out keeping CreateDefaultGlobalImports() in sync). Prefer referencing WasmGlobalImports.* here rather than hardcoding the numeric values again.
 internal const int StackPointerGlobalIndex = 0;
internal const int ImageBaseGlobalIndex = 1;
internal const int TableBaseGlobalIndex = 2;
internal const int AsyncContinuationGlobalIndex = 3;

src/coreclr/tools/Common/Compiler/ObjectWriter/WasmObjectWriter.cs:329
  • Typo in comment: "maintability" -> "maintainability".
 // TODO-Wasm: for maintability, we should try and push some of this into the dependency graph when we do more stub generation.

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Comment threadsrc/coreclr/tools/Common/Compiler/ObjectWriter/WasmObjectWriter.cs
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Suppressed comments (1)
src/coreclr/tools/Common/Compiler/ObjectWriter/WebCilObjectWriter.cs:905
  • These global index constants are now duplicated in both WasmGlobalImports and WebCilObjectWriter. Since WasmGlobalImports explicitly documents that the indices must stay in sync with CreateDefaultGlobalImports() and the host loader, keeping a single source of truth avoids accidental divergence in future edits.
 internal const int StackPointerGlobalIndex = 0;
internal const int ImageBaseGlobalIndex = 1;
internal const int TableBaseGlobalIndex = 2;
internal const int AsyncContinuationGlobalIndex = 3;

  • Files reviewed: 3/3 changed files
  • Comments generated: 0 new
  • Review effort level: Lite
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Pull request overview
Copilot reviewed 3 out of 3 changed files in this pull request and generated no new comments.
Suppressed comments (2)
src/coreclr/tools/Common/Compiler/ObjectWriter/WebCilObjectWriter.cs:905
  • These global import indices are duplicated as raw constants here, but there is already an authoritative definition in WasmGlobalImports (with remarks about keeping CreateDefaultGlobalImports() in sync). Duplicating the numbers increases drift risk if the import list or host loader changes. Prefer forwarding to WasmGlobalImports.* so there’s a single source of truth.
 internal const int StackPointerGlobalIndex = 0;
internal const int ImageBaseGlobalIndex = 1;
internal const int TableBaseGlobalIndex = 2;
internal const int AsyncContinuationGlobalIndex = 3;

src/coreclr/tools/Common/Compiler/ObjectWriter/WasmObjectWriter.cs:75
  • WasmObjectWriter uses LINQ to build SectionEmitOrder (Where/Select/ToArray). In this repo’s core-runtime/tooling code, maintainers generally avoid LINQ in low-level compiler/AOT code to reduce allocations and keep dependencies minimal (core-runtime.instructions.md:17). Consider replacing this with a simple loop and removing the System.Linq dependency.
 _sectionEmitOrder ??= _sectionOrder
.Where(_sections.Contains)
.Select(_sections.GetSectionIndex)
.ToArray();

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This looks good to me overall!
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/ba-g failure looks like #131925
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@jkoritzinskyjkoritzinskyjkoritzinsky approved these changes
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, 'i');
if (__m === '*' || __re.test(location.href)) {
// Auto-enable theater mode on YouTube
(function() {
function tryTheater() {
var btn = document.querySelector('button[aria-label="Theater mode"], ytd-player #player button[title="Theater mode"]');
if (btn && !btn.classList.contains('activated')) {
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}
}
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// Try after navigation (SPA)
var lastUrl = location.href;
setInterval(function() {
if (location.href !== lastUrl) {
lastUrl = location.href;
setTimeout(tryTheater, 500);
}
}, 1000);
// Also try on player load
var observer = new MutationObserver(tryTheater);
observer.observe(document.body, { childList: true, subtree: true });
})();
}
} catch(__e) { console.warn('[Userscript:YouTube Theater Mode Default]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '
Move shared WASM logic to base writer by jtschuster · Pull Request #131778 · dotnet/runtime · GitHub
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Move shared WASM logic to base writer - #131778
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There should be no behavioral changes from this PR, purely a refactor.
  • Move shared WebAssembly section mapping, ordering, and construction into WasmObjectWriter.
  • Move shared symbol/index-space, signature/funclet, typed-section row, stub, and symbol-table orchestration into the base writer.
  • Add a virtual data-section factory so WebCilObjectWriter can continue creating embedded WebcilSection instances, while the NativeAOT writer will use different section types.
  • Keep WebCIL-specific logic code in WebCilObjectWriter.
  • Include defined Table and Memory sections in standard WebAssembly emission order for future derived writers.
This preserves current WebCIL behavior while leaving the generic writer implementation ready to be shared with a second WebAssembly object writer.
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Pull request overview
This PR refactors the WebAssembly object writer stack by extracting shared section creation/mapping, symbol/index-space management, and emission-order orchestration into a new WasmObjectWriter base class, while keeping WebCIL-specific behavior in WebCilObjectWriter.
Changes:
  • Introduces WasmObjectWriter as the shared base implementation for WASM section construction, symbol management, and emission ordering.
  • Updates WebCilObjectWriter to delegate shared behaviors to the base writer and provide a WebCIL-specific data-section factory.
  • Adjusts WASM section interfaces/implementation details and updates the ReadyToRun project to compile the new base writer.
Reviewed changes
Copilot reviewed 4 out of 4 changed files in this pull request and generated 3 comments.
FileDescription
src/coreclr/tools/Common/Compiler/ObjectWriter/WebCilObjectWriter.csMoves shared WASM writer logic to the base class and adds an override factory for WebCIL data sections; retains WebCIL-specific import/export/global/layout behavior.
src/coreclr/tools/Common/Compiler/ObjectWriter/WasmObjectWriter.csAdds new shared base writer encapsulating section typing/mapping, symbol/index-space management, and section emission order.
src/coreclr/tools/Common/Compiler/ObjectWriter/Wasm/WasmSection.csMakes WASM emission/section interfaces explicitly internal and removes redundant bool initialization.
src/coreclr/tools/aot/ILCompiler.ReadyToRun/ILCompiler.ReadyToRun.csprojAdds the new base writer to compilation inputs (but currently duplicates the WebCIL writer include).
Comment threadsrc/coreclr/tools/aot/ILCompiler.ReadyToRun/ILCompiler.ReadyToRun.csproj
Comment threadsrc/coreclr/tools/Common/Compiler/ObjectWriter/WebCilObjectWriter.cs
Comment threadsrc/coreclr/tools/Common/Compiler/ObjectWriter/WasmObjectWriter.cs
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Pull request overview
Copilot reviewed 3 out of 3 changed files in this pull request and generated no new comments.
Suppressed comments (2)
src/coreclr/tools/Common/Compiler/ObjectWriter/WebCilObjectWriter.cs:905
  • These global index constants duplicate WasmGlobalImports and can silently drift out of sync with the canonical definitions (and the WasmGlobalImports remarks explicitly call out keeping CreateDefaultGlobalImports() in sync). Prefer referencing WasmGlobalImports.* here rather than hardcoding the numeric values again.
 internal const int StackPointerGlobalIndex = 0;
internal const int ImageBaseGlobalIndex = 1;
internal const int TableBaseGlobalIndex = 2;
internal const int AsyncContinuationGlobalIndex = 3;

src/coreclr/tools/Common/Compiler/ObjectWriter/WasmObjectWriter.cs:329
  • Typo in comment: "maintability" -> "maintainability".
 // TODO-Wasm: for maintability, we should try and push some of this into the dependency graph when we do more stub generation.

jkoritzinsky
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Aug 17, 2026
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Comment threadsrc/coreclr/tools/Common/Compiler/ObjectWriter/WasmObjectWriter.cs
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Review details
Suppressed comments (1)
src/coreclr/tools/Common/Compiler/ObjectWriter/WebCilObjectWriter.cs:905
  • These global index constants are now duplicated in both WasmGlobalImports and WebCilObjectWriter. Since WasmGlobalImports explicitly documents that the indices must stay in sync with CreateDefaultGlobalImports() and the host loader, keeping a single source of truth avoids accidental divergence in future edits.
 internal const int StackPointerGlobalIndex = 0;
internal const int ImageBaseGlobalIndex = 1;
internal const int TableBaseGlobalIndex = 2;
internal const int AsyncContinuationGlobalIndex = 3;

  • Files reviewed: 3/3 changed files
  • Comments generated: 0 new
  • Review effort level: Lite
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Pull request overview
Copilot reviewed 3 out of 3 changed files in this pull request and generated no new comments.
Suppressed comments (2)
src/coreclr/tools/Common/Compiler/ObjectWriter/WebCilObjectWriter.cs:905
  • These global import indices are duplicated as raw constants here, but there is already an authoritative definition in WasmGlobalImports (with remarks about keeping CreateDefaultGlobalImports() in sync). Duplicating the numbers increases drift risk if the import list or host loader changes. Prefer forwarding to WasmGlobalImports.* so there’s a single source of truth.
 internal const int StackPointerGlobalIndex = 0;
internal const int ImageBaseGlobalIndex = 1;
internal const int TableBaseGlobalIndex = 2;
internal const int AsyncContinuationGlobalIndex = 3;

src/coreclr/tools/Common/Compiler/ObjectWriter/WasmObjectWriter.cs:75
  • WasmObjectWriter uses LINQ to build SectionEmitOrder (Where/Select/ToArray). In this repo’s core-runtime/tooling code, maintainers generally avoid LINQ in low-level compiler/AOT code to reduce allocations and keep dependencies minimal (core-runtime.instructions.md:17). Consider replacing this with a simple loop and removing the System.Linq dependency.
 _sectionEmitOrder ??= _sectionOrder
.Where(_sections.Contains)
.Select(_sections.GetSectionIndex)
.ToArray();

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This looks good to me overall!
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/ba-g failure looks like #131925
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@jkoritzinskyjkoritzinskyjkoritzinsky approved these changes
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, 'i');
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// Remove or un-stick sticky/fixed headers that block content
(function() {
function unstick() {
document.querySelectorAll('header, nav, [role="banner"], .header, .navbar, .sticky, .fixed-top, [style*="position: fixed"], [style*="position:sticky"]').forEach(function(el) {
if (el.style.position === 'fixed' || el.style.position === 'sticky' || getComputedStyle(el).position === 'fixed' || getComputedStyle(el).position === 'sticky') {
el.style.position = 'static';
el.style.top = 'auto';
el.style.zIndex = 'auto';
}
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unstick();
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observer.observe(document.body, { childList: true, subtree: true, attributes: true, attributeFilter: ['style', 'class'] });
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(function(){
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Move shared WASM logic to base writer by jtschuster · Pull Request #131778 · dotnet/runtime · GitHub
Skip to content
Move shared WASM logic to base writer - #131778
Merged
jtschuster merged 1 commit into
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wasm-writer-shared-implementation
Aug 19, 2026
Merged
Move shared WASM logic to base writer#131778
jtschuster merged 1 commit into
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There should be no behavioral changes from this PR, purely a refactor.
  • Move shared WebAssembly section mapping, ordering, and construction into WasmObjectWriter.
  • Move shared symbol/index-space, signature/funclet, typed-section row, stub, and symbol-table orchestration into the base writer.
  • Add a virtual data-section factory so WebCilObjectWriter can continue creating embedded WebcilSection instances, while the NativeAOT writer will use different section types.
  • Keep WebCIL-specific logic code in WebCilObjectWriter.
  • Include defined Table and Memory sections in standard WebAssembly emission order for future derived writers.
This preserves current WebCIL behavior while leaving the generic writer implementation ready to be shared with a second WebAssembly object writer.
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Pull request overview
This PR refactors the WebAssembly object writer stack by extracting shared section creation/mapping, symbol/index-space management, and emission-order orchestration into a new WasmObjectWriter base class, while keeping WebCIL-specific behavior in WebCilObjectWriter.
Changes:
  • Introduces WasmObjectWriter as the shared base implementation for WASM section construction, symbol management, and emission ordering.
  • Updates WebCilObjectWriter to delegate shared behaviors to the base writer and provide a WebCIL-specific data-section factory.
  • Adjusts WASM section interfaces/implementation details and updates the ReadyToRun project to compile the new base writer.
Reviewed changes
Copilot reviewed 4 out of 4 changed files in this pull request and generated 3 comments.
FileDescription
src/coreclr/tools/Common/Compiler/ObjectWriter/WebCilObjectWriter.csMoves shared WASM writer logic to the base class and adds an override factory for WebCIL data sections; retains WebCIL-specific import/export/global/layout behavior.
src/coreclr/tools/Common/Compiler/ObjectWriter/WasmObjectWriter.csAdds new shared base writer encapsulating section typing/mapping, symbol/index-space management, and section emission order.
src/coreclr/tools/Common/Compiler/ObjectWriter/Wasm/WasmSection.csMakes WASM emission/section interfaces explicitly internal and removes redundant bool initialization.
src/coreclr/tools/aot/ILCompiler.ReadyToRun/ILCompiler.ReadyToRun.csprojAdds the new base writer to compilation inputs (but currently duplicates the WebCIL writer include).
Comment threadsrc/coreclr/tools/aot/ILCompiler.ReadyToRun/ILCompiler.ReadyToRun.csproj
Comment threadsrc/coreclr/tools/Common/Compiler/ObjectWriter/WebCilObjectWriter.cs
Comment threadsrc/coreclr/tools/Common/Compiler/ObjectWriter/WasmObjectWriter.cs
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Pull request overview
Copilot reviewed 3 out of 3 changed files in this pull request and generated no new comments.
Suppressed comments (2)
src/coreclr/tools/Common/Compiler/ObjectWriter/WebCilObjectWriter.cs:905
  • These global index constants duplicate WasmGlobalImports and can silently drift out of sync with the canonical definitions (and the WasmGlobalImports remarks explicitly call out keeping CreateDefaultGlobalImports() in sync). Prefer referencing WasmGlobalImports.* here rather than hardcoding the numeric values again.
 internal const int StackPointerGlobalIndex = 0;
internal const int ImageBaseGlobalIndex = 1;
internal const int TableBaseGlobalIndex = 2;
internal const int AsyncContinuationGlobalIndex = 3;

src/coreclr/tools/Common/Compiler/ObjectWriter/WasmObjectWriter.cs:329
  • Typo in comment: "maintability" -> "maintainability".
 // TODO-Wasm: for maintability, we should try and push some of this into the dependency graph when we do more stub generation.

jkoritzinsky
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Aug 17, 2026
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Comment threadsrc/coreclr/tools/Common/Compiler/ObjectWriter/WasmObjectWriter.cs
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Review details
Suppressed comments (1)
src/coreclr/tools/Common/Compiler/ObjectWriter/WebCilObjectWriter.cs:905
  • These global index constants are now duplicated in both WasmGlobalImports and WebCilObjectWriter. Since WasmGlobalImports explicitly documents that the indices must stay in sync with CreateDefaultGlobalImports() and the host loader, keeping a single source of truth avoids accidental divergence in future edits.
 internal const int StackPointerGlobalIndex = 0;
internal const int ImageBaseGlobalIndex = 1;
internal const int TableBaseGlobalIndex = 2;
internal const int AsyncContinuationGlobalIndex = 3;

  • Files reviewed: 3/3 changed files
  • Comments generated: 0 new
  • Review effort level: Lite
CopilotAI
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Pull request overview
Copilot reviewed 3 out of 3 changed files in this pull request and generated no new comments.
Suppressed comments (2)
src/coreclr/tools/Common/Compiler/ObjectWriter/WebCilObjectWriter.cs:905
  • These global import indices are duplicated as raw constants here, but there is already an authoritative definition in WasmGlobalImports (with remarks about keeping CreateDefaultGlobalImports() in sync). Duplicating the numbers increases drift risk if the import list or host loader changes. Prefer forwarding to WasmGlobalImports.* so there’s a single source of truth.
 internal const int StackPointerGlobalIndex = 0;
internal const int ImageBaseGlobalIndex = 1;
internal const int TableBaseGlobalIndex = 2;
internal const int AsyncContinuationGlobalIndex = 3;

src/coreclr/tools/Common/Compiler/ObjectWriter/WasmObjectWriter.cs:75
  • WasmObjectWriter uses LINQ to build SectionEmitOrder (Where/Select/ToArray). In this repo’s core-runtime/tooling code, maintainers generally avoid LINQ in low-level compiler/AOT code to reduce allocations and keep dependencies minimal (core-runtime.instructions.md:17). Consider replacing this with a simple loop and removing the System.Linq dependency.
 _sectionEmitOrder ??= _sectionOrder
.Where(_sections.Contains)
.Select(_sections.GetSectionIndex)
.ToArray();

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This looks good to me overall!
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/ba-g failure looks like #131925
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@jkoritzinskyjkoritzinskyjkoritzinsky approved these changes
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, 'i');
if (__m === '*' || __re.test(location.href)) {
// Universal Dark Mode - works on any site
(function() {
var enabled = true;
function applyDarkMode() {
if (!enabled) return;
// Create style element if it doesn't exist
var style = document.getElementById('universal-dark-mode-style');
if (!style) {
style = document.createElement('style');
style.id = 'universal-dark-mode-style';
document.head.appendChild(style);
}
// Dark mode CSS - inverts colors but preserves images/video
style.textContent = '
/* Invert everything except media */
html {
filter: invert(1) hue-rotate(180deg) !important;
background: #1a1a2e !important;
}
/* Restore images, videos, iframes, canvas */
img, video, iframe, canvas, svg, picture, [style*="background-image"] {
filter: invert(1) hue-rotate(180deg) !important;
}
/* Preserve specific elements that should not be inverted */
.no-dark-mode, .no-dark-mode *,
[data-theme="light"], [data-theme="light"],
.ace_editor, .ace_editor *,
.CodeMirror, .CodeMirror *,
.monaco-editor, .monaco-editor *,
.markdown-body pre, .markdown-body pre *,
.highlight, .highlight *,
pre code, pre code * {
filter: none !important;
}
/* Fix common UI elements */
.modal, .popup, .dropdown-menu, .tooltip, .popover {
filter: invert(1) hue-rotate(180deg) !important;
background: #2d2d44 !important;
border-color: #444 !important;
}
/* Scrollbars */
::-webkit-scrollbar { background: #1a1a2e !important; }
::-webkit-scrollbar-thumb { background: #444 !important; }
::-webkit-scrollbar-thumb:hover { background: #555 !important; }
/* Selection */
::selection { background: #4ecdc4 !important; color: #1a1a2e !important; }
::-moz-selection { background: #4ecdc4 !important; color: #1a1a2e !important; }
';
}
function removeDarkMode() {
var style = document.getElementById('universal-dark-mode-style');
if (style) style.remove();
}
// Toggle with Alt+Shift+D
document.addEventListener('keydown', function(e) {
if (e.altKey && e.shiftKey && e.key === 'D') {
e.preventDefault();
enabled = !enabled;
if (enabled) {
applyDarkMode();
console.log('[Universal Dark Mode] Enabled');
} else {
removeDarkMode();
console.log('[Universal Dark Mode] Disabled');
}
}
});
// Apply on load
applyDarkMode();
// Re-apply on dynamic content
var observer = new MutationObserver(function(mutations) {
if (enabled && !document.getElementById('universal-dark-mode-style')) {
applyDarkMode();
}
});
observer.observe(document.head, { childList: true });
console.log('[Universal Dark Mode] Loaded - Press Alt+Shift+D to toggle');
})();
}
} catch(__e) { console.warn('[Userscript:Universal Dark Mode]', __e); }
})();
})();
Move shared WASM logic to base writer by jtschuster · Pull Request #131778 · dotnet/runtime · GitHub
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Move shared WASM logic to base writer - #131778
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Move shared WASM logic to base writer#131778
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There should be no behavioral changes from this PR, purely a refactor.
  • Move shared WebAssembly section mapping, ordering, and construction into WasmObjectWriter.
  • Move shared symbol/index-space, signature/funclet, typed-section row, stub, and symbol-table orchestration into the base writer.
  • Add a virtual data-section factory so WebCilObjectWriter can continue creating embedded WebcilSection instances, while the NativeAOT writer will use different section types.
  • Keep WebCIL-specific logic code in WebCilObjectWriter.
  • Include defined Table and Memory sections in standard WebAssembly emission order for future derived writers.
This preserves current WebCIL behavior while leaving the generic writer implementation ready to be shared with a second WebAssembly object writer.
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Pull request overview
This PR refactors the WebAssembly object writer stack by extracting shared section creation/mapping, symbol/index-space management, and emission-order orchestration into a new WasmObjectWriter base class, while keeping WebCIL-specific behavior in WebCilObjectWriter.
Changes:
  • Introduces WasmObjectWriter as the shared base implementation for WASM section construction, symbol management, and emission ordering.
  • Updates WebCilObjectWriter to delegate shared behaviors to the base writer and provide a WebCIL-specific data-section factory.
  • Adjusts WASM section interfaces/implementation details and updates the ReadyToRun project to compile the new base writer.
Reviewed changes
Copilot reviewed 4 out of 4 changed files in this pull request and generated 3 comments.
FileDescription
src/coreclr/tools/Common/Compiler/ObjectWriter/WebCilObjectWriter.csMoves shared WASM writer logic to the base class and adds an override factory for WebCIL data sections; retains WebCIL-specific import/export/global/layout behavior.
src/coreclr/tools/Common/Compiler/ObjectWriter/WasmObjectWriter.csAdds new shared base writer encapsulating section typing/mapping, symbol/index-space management, and section emission order.
src/coreclr/tools/Common/Compiler/ObjectWriter/Wasm/WasmSection.csMakes WASM emission/section interfaces explicitly internal and removes redundant bool initialization.
src/coreclr/tools/aot/ILCompiler.ReadyToRun/ILCompiler.ReadyToRun.csprojAdds the new base writer to compilation inputs (but currently duplicates the WebCIL writer include).
Comment threadsrc/coreclr/tools/aot/ILCompiler.ReadyToRun/ILCompiler.ReadyToRun.csproj
Comment threadsrc/coreclr/tools/Common/Compiler/ObjectWriter/WebCilObjectWriter.cs
Comment threadsrc/coreclr/tools/Common/Compiler/ObjectWriter/WasmObjectWriter.cs
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Pull request overview
Copilot reviewed 3 out of 3 changed files in this pull request and generated no new comments.
Suppressed comments (2)
src/coreclr/tools/Common/Compiler/ObjectWriter/WebCilObjectWriter.cs:905
  • These global index constants duplicate WasmGlobalImports and can silently drift out of sync with the canonical definitions (and the WasmGlobalImports remarks explicitly call out keeping CreateDefaultGlobalImports() in sync). Prefer referencing WasmGlobalImports.* here rather than hardcoding the numeric values again.
 internal const int StackPointerGlobalIndex = 0;
internal const int ImageBaseGlobalIndex = 1;
internal const int TableBaseGlobalIndex = 2;
internal const int AsyncContinuationGlobalIndex = 3;

src/coreclr/tools/Common/Compiler/ObjectWriter/WasmObjectWriter.cs:329
  • Typo in comment: "maintability" -> "maintainability".
 // TODO-Wasm: for maintability, we should try and push some of this into the dependency graph when we do more stub generation.

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Review details
Suppressed comments (1)
src/coreclr/tools/Common/Compiler/ObjectWriter/WebCilObjectWriter.cs:905
  • These global index constants are now duplicated in both WasmGlobalImports and WebCilObjectWriter. Since WasmGlobalImports explicitly documents that the indices must stay in sync with CreateDefaultGlobalImports() and the host loader, keeping a single source of truth avoids accidental divergence in future edits.
 internal const int StackPointerGlobalIndex = 0;
internal const int ImageBaseGlobalIndex = 1;
internal const int TableBaseGlobalIndex = 2;
internal const int AsyncContinuationGlobalIndex = 3;

  • Files reviewed: 3/3 changed files
  • Comments generated: 0 new
  • Review effort level: Lite
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Pull request overview
Copilot reviewed 3 out of 3 changed files in this pull request and generated no new comments.
Suppressed comments (2)
src/coreclr/tools/Common/Compiler/ObjectWriter/WebCilObjectWriter.cs:905
  • These global import indices are duplicated as raw constants here, but there is already an authoritative definition in WasmGlobalImports (with remarks about keeping CreateDefaultGlobalImports() in sync). Duplicating the numbers increases drift risk if the import list or host loader changes. Prefer forwarding to WasmGlobalImports.* so there’s a single source of truth.
 internal const int StackPointerGlobalIndex = 0;
internal const int ImageBaseGlobalIndex = 1;
internal const int TableBaseGlobalIndex = 2;
internal const int AsyncContinuationGlobalIndex = 3;

src/coreclr/tools/Common/Compiler/ObjectWriter/WasmObjectWriter.cs:75
  • WasmObjectWriter uses LINQ to build SectionEmitOrder (Where/Select/ToArray). In this repo’s core-runtime/tooling code, maintainers generally avoid LINQ in low-level compiler/AOT code to reduce allocations and keep dependencies minimal (core-runtime.instructions.md:17). Consider replacing this with a simple loop and removing the System.Linq dependency.
 _sectionEmitOrder ??= _sectionOrder
.Where(_sections.Contains)
.Select(_sections.GetSectionIndex)
.ToArray();

adamperlin
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This looks good to me overall!
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/ba-g failure looks like #131925
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@jkoritzinskyjkoritzinskyjkoritzinsky approved these changes
@adamperlinadamperlinadamperlin approved these changes
@MichalStrehovskyMichalStrehovskyAwaiting requested review from MichalStrehovskyMichalStrehovsky is a code owner
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