[Perf] Windows/x86: 1 Regression on 2/24/2026 4:19:41 PM +00:00

### Run Information

Name | Value
-- | --
Architecture | x86
OS | Windows 10.0.22631
Queue | ViperWindows
Baseline | [ae967feaba47c945884fb6ce232621e8616864f8](https://github.com/dotnet/runtime/commit/ae967feaba47c945884fb6ce232621e8616864f8)
Compare | [689ceb67fa96c64772fe4bb87518aa8635f4a314](https://github.com/dotnet/runtime/commit/689ceb67fa96c64772fe4bb87518aa8635f4a314)
Diff | [Diff](https://github.com/dotnet/runtime/compare/ae967feaba47c945884fb6ce232621e8616864f8...689ceb67fa96c64772fe4bb87518aa8635f4a314)
Configs | CompilationMode:tiered, RunKind:micro

### Regressions in System.Collections.ContainsFalse<Int32>

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

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

| 11.92 μs | 14.56 μs | 1.22 | 0.22 | False | | |

[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
py .\performance\scripts\benchmarks_ci.py -f net8.0 --filter 'System.Collections.ContainsFalse*'
```

### System.Collections.ContainsFalse<Int32>.List(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 at src/benchmarks/micro/libraries/System.Collections/Contains/ContainsFalse.cs#L69-L78 and reproduce the result with the provided benchmarks_ci.py command. Compare the baseline and test commits and use the linked test report and IR history to investigate the 22% regression. Done means the regression is explained and an appropriate correction is identified and validated.

Written by the indexing model from the issue text.