[Perf] Linux/x64: 1 Improvement on 7/17/2026 12:15:56 AM +00:00

### Run Information

Name | Value
-- | --
Architecture | x64
OS | ubuntu 22.04
Queue | ViperUbuntu
Baseline | [b78a8f8b1d15898ba39eb4fd63e2578edcf16c37](https://github.com/dotnet/runtime/commit/b78a8f8b1d15898ba39eb4fd63e2578edcf16c37)
Compare | [09f41d9272e6dcff30bfa15653e124d013167e05](https://github.com/dotnet/runtime/commit/09f41d9272e6dcff30bfa15653e124d013167e05)
Diff | [Diff](https://github.com/dotnet/runtime/compare/b78a8f8b1d15898ba39eb4fd63e2578edcf16c37...09f41d9272e6dcff30bfa15653e124d013167e05)
Configs | CompilationMode:wasm, RunKind:micro, RuntimeType:coreclr

### Improvements in System.Collections.ContainsFalse<String>

Benchmark | Baseline | Test | Test/Base | Test Quality | Edge Detector | Baseline IR | Compare IR | IR Ratio
-- | -- | -- | -- | -- | -- | -- | -- | --
|

• [Span - Duration of single invocation]()
• 📝 - [Benchmark Source]()
• [ADX - Test Multi Config Graph]()

![graph]()
[Test Report]()

### Repro
General Docs link: https://github.com/dotnet/performance/blob/main/docs/benchmarking-workflow-dotnet-runtime.md

```cmd
git clone https://github.com/dotnet/performance.git
python3 .\performance\scripts\benchmarks_ci.py -f net8.0 --filter 'System.Collections.ContainsFalse*'
```

### System.Collections.ContainsFalse<String>.Span(Size: 512)

#### ETL Files

#### Histogram

#### JIT Disasms

### Docs

[Profiling workflow for dotnet/runtime repository](https://github.com/dotnet/performance/blob/master/docs/profiling-workflow-dotnet-runtime.md)
[Benchmarking workflow for dotnet/runtime repository](https://github.com/dotnet/performance/blob/master/docs/benchmarking-workflow-dotnet-runtime.md)

Start with the benchmark source in src/benchmarks/micro/libraries/System.Collections/Contains/ContainsFalse.cs#L54-L64 and reproduce it with the provided benchmarks_ci.py command. Compare the baseline and test commits, then inspect the linked Test Report and benchmark history to identify what explains the measured improvement. Done requires a supported explanation and a validated runtime or benchmark change, but the issue does not define a specific fix.

Written by the indexing model from the issue text.