[Perf] Windows/x64: 2 Regressions on 2/21/2026 2:04:37 AM +00:00

### Run Information

Name | Value
-- | --
Architecture | x64
OS | Windows 10.0.22631
Queue | ViperWindows
Baseline | [d97a9c19c1281ac1c27c2a7c5a8cf727b17cea69](https://github.com/dotnet/runtime/commit/d97a9c19c1281ac1c27c2a7c5a8cf727b17cea69)
Compare | [c5d5be4b636b5dad36edf8131a7ce1049488991c](https://github.com/dotnet/runtime/commit/c5d5be4b636b5dad36edf8131a7ce1049488991c)
Diff | [Diff](https://github.com/dotnet/runtime/compare/d97a9c19c1281ac1c27c2a7c5a8cf727b17cea69...c5d5be4b636b5dad36edf8131a7ce1049488991c)
Configs | CompilationMode:tiered, RunKind:micro

### Regressions in System.Tests.Perf_Enum

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

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

| 12.38 ns | 19.72 ns | 1.59 | 0.29 | False | | |
|

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

| 12.63 ns | 16.66 ns | 1.32 | 0.27 | False | | |

![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
py .\performance\scripts\benchmarks_ci.py -f net8.0 --filter 'System.Tests.Perf_Enum*'
```

### System.Tests.Perf_Enum.ToString_NonFlags_Large(value: UppercaseLetter)

#### ETL Files

#### Histogram

#### JIT Disasms

### System.Tests.Perf_Enum.ToString_NonFlags_Small(value: TopDirectoryOnly)

#### 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)