Reduce allocations during SourceGeneration #78403
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SourceGenerator.DoGenerate was previously writing the text into a StringBuilder, wrapping that in a TextReader, and creating a SourceText from that. Creation of that source text would end up allocating in SourceText.From (likely from calling ReadToEnd in the give text reader) Instead, we can use a copy of the (unused) StringBuilderText and just use that as the source text.
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@dotnet/roslyn-compiler -- PTAL as it looks like this one needs compiler reviews. |
jjonescz
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May 6, 2025
src/Tools/Source/CompilerGeneratorTools/Source/CSharpSyntaxGenerator/SourceGenerator.cs
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@chsienki PTAL |
chsienki
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* upstream/main: (415 commits) Use lazy initialization for members in CodeFixService (dotnet#78484) Targeted perf changes to CommandLineParser (dotnet#78446) Exclude VS.ExternalAPIs.Roslyn.Package from source-build Add syntax highlighting of ignored directives (dotnet#78458) Fix unexpected conditional state in nullable analysis of conditional access (dotnet#78439) Update RoslynAnalyzers to use Roslyns version Fix source-build by renaming Assets folder to assets Unlist M.CA.AnalyzerUtilities as an expected DevDivInsertion dependency Use a project reference for M.CA.AnalyzerUtilities Rectify status of dictionary expressions (dotnet#78497) Remove unused field Remove unused field Remove using Fix check Update eng/config/PublishData.json Make internal Remove now unused methods from IWorkspaceProjectContext (dotnet#78479) Reduce allocations during SourceGeneration (dotnet#78403) Update Roslyn.sln Merge EditorFeatures.Wpf entirely into EditorFeatures ...
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SourceGenerator.DoGenerate was previously writing the text into a StringBuilder, wrapping that in a TextReader, and creating a SourceText from that. Creation of that source text would end up allocating in SourceText.From (likely from calling ReadToEnd in the give text reader)
Instead, we can use a copy of the (unused) StringBuilderText class and just use that as the source text.