Speed up union subset checks by scanning sorted constituents by Andarist · Pull Request #64964 · microsoft/TypeScript

Mateusz Burzyński (Andarist) · 2026-10-25T22:50:42Z

No description provided.

…arches

typescript-automation · 2026-10-25T22:50:48Z

This PR doesn't have any linked issues. Please open an issue that references this PR. From there we can discuss and prioritise.

Copilot

🟡 Changes recommended

Sparse subset checks now require linear rather than logarithmic search work against large target unions.

1 open issue

Avoid linear scans for sparse source unions · New

What changed in this PR

This PR changes union-subset checking in the native TypeScript checker to use a forward identity scan instead of repeated binary searches.

Changes:

Rejects source unions with more members than the target.
Searches progressively shorter target slices, relying on sorted union members.

File	Description
`tsc/internal/checker/relater.go`	Replaces per-member binary searches with a forward scan and adds a size guard.

_{Review effort: Balanced}

Copilot

🟢 Approval recommended

The focused change preserves subset semantics under the established sorted, deduplicated union invariant, with no blocking issues identified.

No open issues 🎉

1 resolved since last review

Avoid linear scans for sparse source unions

_{Review effort: Balanced}

…he previous match

Daniel Rosenwasser (DanielRosenwasser) · 2026-10-26T16:46:15Z

+			}
+			return true
+		}
+		for _, t := range sourceTypes {


Suggested change

for _, t := range sourceTypes {

for _, t := range sourceTypes {

Jake Bailey (jakebailey) · 2026-10-26T18:56:30Z

TypeScript Bot (@typescript-bot) perf test this faster

typescript-automation · 2026-10-26T18:56:36Z

Starting jobs; this comment will be updated as builds start and complete.

Command	Status	Results
`perf test this faster`	✅ Started	❌ Results

typescript-automation · 2026-10-26T18:59:48Z

Jake Bailey (@jakebailey), the perf run you requested failed. You can check the log here.

Jake Bailey (jakebailey) · 2026-10-26T19:18:13Z

TypeScript Bot (@typescript-bot) perf test this faster

typescript-automation · 2026-10-26T19:18:19Z

Starting jobs; this comment will be updated as builds start and complete.

Command	Status	Results
`perf test this faster`	✅ Started	❌ Results

typescript-automation · 2026-10-26T23:53:45Z

Jake Bailey (@jakebailey), the perf run you requested failed. You can check the log here.

typescript-automation · 2026-10-27T10:26:11Z

Jake Bailey (@jakebailey)
The results of the perf run you requested are in!

Here they are:

Provisional hosted-runner results: these VMs are not the dedicated benchmark machines. Results may be noisier and are not comparable to the historical series. For comparisons, both revisions of each scenario ran on the same VM.

tsc

Comparison Report - baseline..pr

_Metric	_baseline	_pr	_Delta	_Best	_Worst	_p-value
_{Compiler-Unions - native}
_Errors	₄₁	₄₁	_~	_~	_~	_{p=1.000 n=12}
_Symbols	_88,466	_88,466	_~	_~	_~	_{p=1.000 n=12}
_Types	_79,607	_79,607	_~	_~	_~	_{p=1.000 n=12}
_{Memory Used}	_{109,254k (± 0.08%)}	_{109,206k (± 0.06%)}	_~	_109,051k	_109,398k	_{p=0.744 n=12}
_{Memory Allocs}	_{2,196,809 (± 0.00%)}	_{2,196,703 (± 0.01%)}	_~	_2,196,481	_2,197,142	_{p=0.110 n=12}
_{Config Time}	_0.000s	_0.000s	_~	_~	_~	_{p=1.000 n=12}
_{Parse Time}	_{0.042s (± 3.52%)}	_{0.043s (± 3.75%)}	_~	_0.037s	_0.045s	_{p=0.448 n=12}
_{Bind Time}	_{0.018s (± 9.40%)}	_{0.019s (±11.73%)}	_~	_0.015s	_0.026s	_{p=0.616 n=12}
_{Check Time}	_{0.445s (± 1.88%)}	_{0.405s (± 3.44%)}	_{🟩-0.039s (- 8.88%)}	_0.381s	_0.454s	_{p=0.000 n=12}
_{Emit Time}	_{0.298s (± 3.46%)}	_{0.283s (± 2.83%)}	_{🟩-0.015s (- 4.92%)}	_0.265s	_0.306s	_{p=0.015 n=12}
_{Total Time}	_{0.809s (± 1.29%)}	_{0.757s (± 2.70%)}	_{🟩-0.053s (- 6.50%)}	_0.727s	_0.833s	_{p=0.000 n=12}
_{angular-1 - native}
_Errors	₃	₃	_~	_~	_~	_{p=1.000 n=12}
_Symbols	_{586,578 (± 0.03%)}	_{586,535 (± 0.02%)}	_~	_586,028	_586,854	_{p=0.977 n=12}
_Types	_{241,692 (± 0.00%)}	_{241,692 (± 0.00%)}	_~	_241,688	_241,695	_{p=0.535 n=12}
_{Memory Used}	_{551,150k (± 0.03%)}	_{551,084k (± 0.02%)}	_~	_550,811k	_551,368k	_{p=0.478 n=12}
_{Memory Allocs}	_{13,073,246 (± 0.04%)}	_{13,070,127 (± 0.01%)}	_~	_13,066,693	_13,074,471	_{p=0.977 n=12}
_{Config Time}	_{0.017s (± 2.46%)}	_{0.017s (± 2.33%)}	_~	_0.016s	_0.018s	_{p=0.199 n=12}
_{Parse Time}	_{0.194s (± 4.63%)}	_{0.192s (± 5.47%)}	_~	_0.174s	_0.229s	_{p=0.504 n=12}
_{Bind Time}	_{0.058s (±12.45%)}	_{0.057s (±12.81%)}	_~	_0.050s	_0.084s	_{p=0.291 n=12}
_{Check Time}	_0s	_0s	_~	_~	_~	_{p=1.000 n=12}
_{Emit Time}	_{1.157s (± 1.47%)}	_{1.160s (± 0.95%)}	_~	_1.137s	_1.197s	_{p=0.989 n=12}
_{Total Time}	_{1.440s (± 1.48%)}	_{1.439s (± 1.01%)}	_~	_1.415s	_1.480s	_{p=0.854 n=12}
_{arktype - native}
_Errors	₀	₀	_~	_~	_~	_{p=1.000 n=12}
_Symbols	_685,943	_685,943	_~	_~	_~	_{p=1.000 n=12}
_Types	_939,490	_939,490	_~	_~	_~	_{p=1.000 n=12}
_{Memory Used}	_{533,269k (± 0.01%)}	_{533,143k (± 0.01%)}	_{-126k (- 0.02%)}	_533,042k	_533,352k	_{p=0.000 n=12}
_{Memory Allocs}	_{12,772,465 (± 0.02%)}	_{12,770,075 (± 0.01%)}	_~	_12,768,064	_12,775,734	_{p=0.089 n=12}
_{Config Time}	_0.002s	_0.002s	_~	_~	_~	_{p=1.000 n=12}
_{Parse Time}	_{0.061s (± 4.11%)}	_{0.061s (± 5.31%)}	_~	_0.053s	_0.070s	_{p=1.000 n=12}
_{Bind Time}	_{0.020s (±11.92%)}	_{0.019s (± 9.34%)}	_~	_0.016s	_0.026s	_{p=0.989 n=12}
_{Check Time}	_{1.397s (± 0.69%)}	_{1.382s (± 0.32%)}	_{-0.015s (- 1.07%)}	_1.368s	_1.392s	_{p=0.003 n=12}
_{Emit Time}	_0.000s	_0.000s	_~	_~	_~	_{p=1.000 n=12}
_{Total Time}	_{1.518s (± 0.60%)}	_{1.504s (± 0.39%)}	_{-0.014s (- 0.93%)}	_1.490s	_1.521s	_{p=0.014 n=12}
_{mui-docs - native}
_Errors	_11,405	_11,405	_~	_~	_~	_{p=1.000 n=12}
_Symbols	_3,784,027	_3,784,027	_~	_~	_~	_{p=1.000 n=12}
_Types	_1,355,982	_1,355,982	_~	_~	_~	_{p=1.000 n=12}
_{Memory Used}	_{2,197,614k (± 0.08%)}	_{2,198,870k (± 0.08%)}	_~	_2,194,860k	_2,203,450k	_{p=0.266 n=12}
_{Memory Allocs}	_{26,469,431 (± 0.06%)}	_{26,474,423 (± 0.09%)}	_~	_26,410,711	_26,558,487	_{p=0.755 n=12}
_{Config Time}	_{0.014s (± 2.00%)}	_{0.014s (± 1.29%)}	_~	_0.014s	_0.015s	_{p=0.590 n=12}
_{Parse Time}	_{0.495s (± 2.96%)}	_{0.504s (± 2.38%)}	_~	_0.459s	_0.522s	_{p=0.272 n=12}
_{Bind Time}	_{0.002s (±21.90%)}	_{0.001s (±22.86%)}	_~	_0.001s	_0.002s	_{p=1.000 n=12}
_{Check Time}	_{4.808s (± 0.38%)}	_{4.817s (± 0.38%)}	_~	_4.758s	_4.865s	_{p=0.434 n=12}
_{Emit Time}	_{0.370s (± 5.00%)}	_{0.364s (± 5.04%)}	_~	_0.336s	_0.399s	_{p=0.467 n=12}
_{Total Time}	_{6.497s (± 0.79%)}	_{6.484s (± 0.54%)}	_~	_6.417s	_6.631s	_{p=1.000 n=12}
_{sentry - native}
_Errors	₂	₂	_~	_~	_~	_{p=1.000 n=12}
_Symbols	_4,793,249	_4,793,249	_~	_~	_~	_{p=1.000 n=12}
_Types	_2,607,051	_2,607,051	_~	_~	_~	_{p=1.000 n=12}
_{Memory Used}	_{3,206,139k (± 0.05%)}	_{3,206,534k (± 0.06%)}	_~	_3,203,701k	_3,212,410k	_{p=0.843 n=12}
_{Memory Allocs}	_{75,290,910 (± 0.10%)}	_{75,268,233 (± 0.11%)}	_~	_75,034,163	_75,534,626	_{p=0.843 n=12}
_{Config Time}	_0.044s	_{0.045s (± 0.73%)}	_{+0.001s (+ 1.33%)}	_0.044s	_0.045s	_{p=0.005 n=12}
_{Parse Time}	_{0.687s (± 1.51%)}	_{0.700s (± 4.25%)}	_~	_0.639s	_0.801s	_{p=0.723 n=12}
_{Bind Time}	_{0.195s (±12.72%)}	_{0.202s (±10.93%)}	_~	_0.174s	_0.286s	_{p=0.181 n=12}
_{Check Time}	_{9.281s (± 0.45%)}	_{9.295s (± 0.42%)}	_~	_9.199s	_9.431s	_{p=0.434 n=12}
_{Emit Time}	_0.000s	_0.000s	_~	_~	_~	_{p=1.000 n=12}
_{Total Time}	_{10.264s (± 0.49%)}	_{10.303s (± 0.44%)}	_~	_10.174s	_10.385s	_{p=0.143 n=12}
_{social-app - native}
_Errors	₀	₀	_~	_~	_~	_{p=1.000 n=12}
_Symbols	_1,883,075	_1,883,075	_~	_~	_~	_{p=1.000 n=12}
_Types	_1,158,171	_1,158,171	_~	_~	_~	_{p=1.000 n=12}
_{Memory Used}	_{1,056,677k (± 0.02%)}	_{1,056,904k (± 0.02%)}	_~	_1,055,912k	_1,057,272k	_{p=0.101 n=12}
_{Memory Allocs}	_{13,570,757 (± 0.11%)}	_{13,584,287 (± 0.16%)}	_~	_13,538,818	_13,639,793	_{p=0.478 n=12}
_{Config Time}	_{0.015s (± 2.22%)}	_{0.015s (± 2.22%)}	_~	_0.014s	_0.015s	_{p=1.000 n=12}
_{Parse Time}	_{0.237s (± 2.16%)}	_{0.247s (± 1.97%)}	_{🔻+0.010s (+ 4.26%)}	_0.239s	_0.263s	_{p=0.019 n=12}
_{Bind Time}	_{0.057s (±11.28%)}	_{0.052s (±10.32%)}	_~	_0.046s	_0.078s	_{p=0.338 n=12}
_{Check Time}	_{2.151s (± 0.25%)}	_{2.148s (± 0.54%)}	_~	_2.125s	_2.186s	_{p=0.224 n=12}
_{Emit Time}	_0.000s	_0.000s	_~	_~	_~	_{p=1.000 n=12}
_{Total Time}	_{2.479s (± 0.46%)}	_{2.479s (± 0.49%)}	_~	_2.452s	_2.513s	_{p=0.991 n=12}
_{strada-build-src - native}
_Errors	₀	₀	_~	_~	_~	_{p=1.000 n=12}
_Symbols	_1,184,976	_1,184,976	_~	_~	_~	_{p=1.000 n=12}
_Types	_438,967	_438,967	_~	_~	_~	_{p=1.000 n=12}
_{Memory Used}	_{1,257,581k (± 0.45%)}	_{1,259,940k (± 0.34%)}	_~	_1,248,240k	_1,268,285k	_{p=0.590 n=12}
_{Memory Allocs}	_{76,894,331 (± 0.15%)}	_{76,930,792 (± 0.19%)}	_~	_76,632,349	_77,366,767	_{p=0.443 n=12}
_{Config Time}	_{0.004s (±18.41%)}	_{0.004s (±10.74%)}	_~	_0.003s	_0.005s	_{p=0.617 n=12}
_{Parse Time}	_{0.180s (± 1.64%)}	_{0.180s (± 2.05%)}	_~	_0.169s	_0.190s	_{p=0.876 n=12}
_{Bind Time}	_0.000s	_{0.000s (±217.90%)}	_~	_0.000s	_0.002s	_{p=1.000 n=12}
_{Check Time}	_{1.189s (± 0.38%)}	_{1.099s (± 0.48%)}	_{🟩-0.090s (- 7.57%)}	_1.087s	_1.117s	_{p=0.000 n=12}
_{Emit Time}	_{0.212s (± 1.41%)}	_{0.216s (± 2.33%)}	_~	_0.204s	_0.231s	_{p=0.339 n=12}
_{Total Time}	_{14.020s (± 0.52%)}	_{13.215s (± 0.45%)}	_{🟩-0.805s (- 5.74%)}	_13.056s	_13.324s	_{p=0.000 n=12}
_{strada-compiler - native}
_Errors	₀	₀	_~	_~	_~	_{p=1.000 n=12}
_Symbols	_263,513	_263,513	_~	_~	_~	_{p=1.000 n=12}
_Types	_196,118	_196,118	_~	_~	_~	_{p=1.000 n=12}
_{Memory Used}	_{236,088k (± 0.02%)}	_{236,126k (± 0.02%)}	_~	_235,977k	_236,219k	_{p=0.139 n=12}
_{Memory Allocs}	_{4,287,635 (± 0.01%)}	_{4,287,759 (± 0.01%)}	_~	_4,286,942	_4,288,773	_{p=1.000 n=12}
_{Config Time}	_0.001s	_0.001s	_~	_~	_~	_{p=1.000 n=12}
_{Parse Time}	_{0.073s (± 4.42%)}	_{0.073s (± 5.31%)}	_~	_0.064s	_0.082s	_{p=1.000 n=12}
_{Bind Time}	_0.000s	_0.000s	_~	_~	_~	_{p=1.000 n=12}
_{Check Time}	_{0.605s (± 0.69%)}	_{0.564s (± 1.37%)}	_{🟩-0.041s (- 6.81%)}	_0.551s	_0.588s	_{p=0.000 n=12}
_{Emit Time}	_{0.095s (± 2.87%)}	_{0.096s (± 1.75%)}	_~	_0.092s	_0.101s	_{p=0.540 n=12}
_{Total Time}	_{0.813s (± 0.72%)}	_{0.771s (± 0.92%)}	_{🟩-0.042s (- 5.13%)}	_0.760s	_0.796s	_{p=0.000 n=12}
_{t3code-server - native}
_Errors	₀	₀	_~	_~	_~	_{p=1.000 n=12}
_Symbols	_4,350,705	_4,350,705	_~	_~	_~	_{p=1.000 n=12}
_Types	_3,040,691	_3,040,691	_~	_~	_~	_{p=1.000 n=12}
_{Memory Used}	_{2,610,578k (± 0.03%)}	_{2,610,261k (± 0.02%)}	_~	_2,609,369k	_2,611,592k	_{p=0.443 n=12}
_{Memory Allocs}	_{37,339,381 (± 0.06%)}	_{37,316,938 (± 0.03%)}	_~	_37,273,558	_37,346,783	_{p=0.198 n=12}
_{Config Time}	_0.005s	_{0.005s (± 7.03%)}	_~	_0.005s	_0.007s	_{p=1.000 n=12}
_{Parse Time}	_{0.371s (± 3.63%)}	_{0.389s (± 3.16%)}	_{🔻+0.018s (+ 4.92%)}	_0.357s	_0.418s	_{p=0.046 n=12}
_{Bind Time}	_{0.125s (±11.77%)}	_{0.114s (± 2.85%)}	_~	_0.108s	_0.124s	_{p=0.701 n=12}
_{Check Time}	_{11.023s (± 0.57%)}	_{11.097s (± 0.69%)}	_~	_10.918s	_11.259s	_{p=0.160 n=12}
_{Emit Time}	_0.000s	_0.000s	_~	_~	_~	_{p=1.000 n=12}
_{Total Time}	_{11.538s (± 0.52%)}	_{11.619s (± 0.64%)}	_~	_11.453s	_11.799s	_{p=0.114 n=12}
_{ts-pre-modules - native}
_Errors	₈₇	₈₇	_~	_~	_~	_{p=1.000 n=12}
_Symbols	_231,617	_231,617	_~	_~	_~	_{p=1.000 n=12}
_Types	_181,196	_181,196	_~	_~	_~	_{p=1.000 n=12}
_{Memory Used}	_{203,537k (± 0.02%)}	_{203,548k (± 0.02%)}	_~	_203,467k	_203,654k	_{p=0.932 n=12}
_{Memory Allocs}	_{1,358,061 (± 0.01%)}	_{1,358,187 (± 0.01%)}	_~	_1,357,978	_1,358,488	_{p=0.078 n=12}
_{Config Time}	_0.000s	_0.000s	_~	_~	_~	_{p=1.000 n=12}
_{Parse Time}	_{0.062s (± 4.48%)}	_{0.063s (± 4.04%)}	_~	_0.057s	_0.070s	_{p=0.700 n=12}
_{Bind Time}	_{0.027s (± 5.40%)}	_{0.028s (± 5.12%)}	_~	_0.024s	_0.032s	_{p=0.385 n=12}
_{Check Time}	_{0.462s (± 0.70%)}	_{0.424s (± 0.53%)}	_{🟩-0.038s (- 8.29%)}	_0.419s	_0.430s	_{p=0.000 n=12}
_{Emit Time}	_0.000s	_0.000s	_~	_~	_~	_{p=1.000 n=12}
_{Total Time}	_{0.562s (± 0.70%)}	_{0.526s (± 0.64%)}	_{🟩-0.037s (- 6.52%)}	_0.517s	_0.534s	_{p=0.000 n=12}
_{vscode - native}
_Errors	₁₀	₁₀	_~	_~	_~	_{p=1.000 n=12}
_Symbols	_7,281,695	_7,281,695	_~	_~	_~	_{p=1.000 n=12}
_Types	_4,286,835	_4,286,835	_~	_~	_~	_{p=1.000 n=12}
_{Memory Used}	_{5,404,544k (± 0.02%)}	_{5,405,000k (± 0.02%)}	_~	_5,402,941k	_5,407,436k	_{p=0.291 n=12}
_{Memory Allocs}	_{62,550,682 (± 0.01%)}	_{62,554,333 (± 0.01%)}	_~	_62,546,073	_62,574,884	_{p=0.590 n=12}
_{Config Time}	_{0.068s (± 0.39%)}	_{0.068s (± 0.54%)}	_~	_0.067s	_0.069s	_{p=0.496 n=12}
_{Parse Time}	_{1.249s (± 1.59%)}	_{1.250s (± 1.64%)}	_~	_1.167s	_1.292s	_{p=0.843 n=12}
_{Bind Time}	_{0.416s (± 9.24%)}	_{0.417s (± 9.92%)}	_~	_0.386s	_0.615s	_{p=0.723 n=12}
_{Check Time}	_{11.300s (± 0.34%)}	_{11.237s (± 0.49%)}	_~	_11.073s	_11.402s	_{p=0.058 n=12}
_{Emit Time}	_{3.829s (± 3.73%)}	_{3.801s (± 4.58%)}	_~	_3.576s	_4.329s	_{p=0.443 n=12}
_{Total Time}	_{16.930s (± 0.82%)}	_{16.842s (± 0.96%)}	_~	_16.591s	_17.318s	_{p=0.219 n=12}
_{webpack - native}
_Errors	₆₁₇	₆₁₇	_~	_~	_~	_{p=1.000 n=12}
_Symbols	_922,055	_922,055	_~	_~	_~	_{p=1.000 n=12}
_Types	_644,701	_644,701	_~	_~	_~	_{p=1.000 n=12}
_{Memory Used}	_{776,140k (± 0.03%)}	_{776,186k (± 0.01%)}	_~	_775,896k	_776,502k	_{p=0.541 n=12}
_{Memory Allocs}	_{6,570,809 (± 0.01%)}	_{6,571,823 (± 0.02%)}	_~	_6,570,225	_6,577,253	_{p=0.259 n=12}
_{Config Time}	_0.007s	_0.007s	_~	_~	_~	_{p=1.000 n=12}
_{Parse Time}	_{0.201s (± 4.54%)}	_{0.203s (± 4.13%)}	_~	_0.183s	_0.223s	_{p=0.944 n=12}
_{Bind Time}	_{0.063s (±11.94%)}	_{0.064s (±13.06%)}	_~	_0.051s	_0.085s	_{p=0.578 n=12}
_{Check Time}	_{1.693s (± 0.45%)}	_{1.674s (± 0.49%)}	_{-0.019s (- 1.12%)}	_1.652s	_1.692s	_{p=0.001 n=12}
_{Emit Time}	_0.000s	_0.000s	_~	_~	_~	_{p=1.000 n=12}
_{Total Time}	_{1.998s (± 0.51%)}	_{1.982s (± 0.44%)}	_{-0.016s (- 0.80%)}	_1.953s	_2.001s	_{p=0.016 n=12}
_{xstate-main - native}
_Errors	₀	₀	_~	_~	_~	_{p=1.000 n=12}
_Symbols	_640,494	_640,494	_~	_~	_~	_{p=1.000 n=12}
_Types	_387,992	_387,992	_~	_~	_~	_{p=1.000 n=12}
_{Memory Used}	_{398,375k (± 0.03%)}	_{398,492k (± 0.04%)}	_~	_398,241k	_399,021k	_{p=0.198 n=12}
_{Memory Allocs}	_{3,989,975 (± 0.10%)}	_{3,991,090 (± 0.09%)}	_~	_3,983,271	_4,000,838	_{p=0.932 n=12}
_{Config Time}	_0.002s	_0.002s	_~	_~	_~	_{p=1.000 n=12}
_{Parse Time}	_{0.088s (± 1.98%)}	_{0.088s (± 3.20%)}	_~	_0.080s	_0.094s	_{p=0.899 n=12}
_{Bind Time}	_{0.027s (± 8.76%)}	_{0.027s (±11.17%)}	_~	_0.023s	_0.037s	_{p=0.720 n=12}
_{Check Time}	_{0.618s (± 0.97%)}	_{0.613s (± 0.87%)}	_~	_0.600s	_0.627s	_{p=0.202 n=12}
_{Emit Time}	_0.000s	_0.000s	_~	_~	_~	_{p=1.000 n=12}
_{Total Time}	_{0.742s (± 0.85%)}	_{0.737s (± 0.95%)}	_~	_0.721s	_0.750s	_{p=0.271 n=12}

System info unknown

Hosts

native

Scenarios

Compiler-Unions - native
angular-1 - native
arktype - native
mui-docs - native
sentry - native
social-app - native
strada-build-src - native
strada-compiler - native
t3code-server - native
ts-pre-modules - native
vscode - native
webpack - native
xstate-main - native

_Benchmark	_Name	_Iterations
_Current	_pr	₁₂
_Baseline	_baseline	₁₂

Developer Information:

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Check union subsets with a forward identity scan instead of binary se…

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Mateusz Burzyński (Andarist) force-pushed the andarist/sorted-subset-union-scan branch from 69739e1 to d2050ae Compare October 26, 2026 07:06

Mateusz Burzyński (Andarist) changed the title ~~Check union subsets with a forward identity scan instead of binary searches~~ Speed up union subset checks by scanning sorted constituents Oct 26, 2026

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Mateusz Burzyński (Andarist) mentioned this pull request Oct 26, 2026

perf(checker): search sparse union subsets only after the previous match oxc-project/tsrs#798

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Binary search sparse union subsets, and search each type only after t…

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Mateusz Burzyński (Andarist) force-pushed the andarist/sorted-subset-union-scan branch from d2050ae to 4c35db3 Compare October 26, 2026 09:22

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Merge branch 'main' into andarist/sorted-subset-union-scan

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Merged via the queue into microsoft:main with commit 97aedd3 Oct 28, 2026
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	for _, t := range sourceTypes {

	for _, t := range sourceTypes {

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