Cache normalized file names to avoid re-allocating them per cursor - #708
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tannergooding merged 1 commit intoJul 12, 2026
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IsIncludedFileOrLocation runs for every cursor and re-derives the file's normalized name from scratch each time -- file.Name.ToString().NormalizePath(), plus a NormalizeFullPath() (Path.GetFullPath) on the traversal-name path. The same file recurs for every cursor it contains, so this repeats the same work thousands of times. Cache the normalized name and full name per CXFile, mirroring the existing _fileContents cache (same key type, cleared per translation unit in GenerateBindings). On the TerraFX Windows SDK d3d12 generation this drops sampled allocations from 179.6 MB to 142.7 MB (~20%), eliminating the 18.0 MB of NormalizePath and 8.7 MB of NormalizeFullPath entirely. Co-authored-by: Copilot App <223556219+Copilot@users.noreply.github.com>
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IsIncludedFileOrLocationruns for every cursor (viaIsExcluded) and re-derives the file's normalized name from scratch each time --file.Name.ToString().NormalizePath(), plus aNormalizeFullPath()(Path.GetFullPath) on the traversal-name path. The same file recurs for every cursor it contains, so this repeats identical work thousands of times per generation.Cache the normalized name and full name per
CXFile, mirroring the existing_fileContentscache -- same key type, populated on miss, cleared per translation unit inGenerateBindings.Measured on the TerraFX Windows SDK generation (
DirectX/d3d12) withDOTNET_TieredCompilation=0(the NativeAOT-representative full-opt proxy the shipped tool runs under), sampledGCAllocationTick, before vs. after this change:StringExtensions.NormalizePathStringExtensions.NormalizeFullPath~20% fewer allocations overall; both normalization frames drop out of the profile entirely. All 3706 generator tests pass and the build is warning-clean.
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This PR body was drafted by Copilot.