[Perf] Windows/x64: 2 Improvements on 7/7/2026 3:51:29 PM +00:00

### Run Information

Name | Value
-- | --
Architecture | x64
OS | Windows 10.0.22631
Queue | ViperWindows
Baseline | [9879c00a4acf10dae77c3957a8250382181f2583](https://github.com/dotnet/runtime/commit/9879c00a4acf10dae77c3957a8250382181f2583)
Compare | [f475c19ddfd8b94cd311712cb799c4be14bd6d31](https://github.com/dotnet/runtime/commit/f475c19ddfd8b94cd311712cb799c4be14bd6d31)
Diff | [Diff](https://github.com/dotnet/runtime/compare/9879c00a4acf10dae77c3957a8250382181f2583...f475c19ddfd8b94cd311712cb799c4be14bd6d31)
Configs | CompilationMode:tiered, RunKind:micro

### Improvements in System.Reflection.Attributes

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

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

| 431.47 ns | 371.07 ns | 0.86 | 0.21 | False | | |
|

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

| 414.66 ns | 365.52 ns | 0.88 | 0.21 | 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.Reflection.Attributes*'
```

### System.Reflection.Attributes.IsDefinedClassHitInherit

#### ETL Files

#### Histogram

#### JIT Disasms

### System.Reflection.Attributes.IsDefinedClassHit

#### 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 cases in src/benchmarks/micro/runtime/System.Reflection/Attributes.cs at lines 87-94, then run the supplied benchmarks_ci.py command with the System.Reflection.Attributes* filter. Compare the Windows/x64 results against the linked baseline and test commits; done means the reported performance change is understood and appropriately addressed.

Written by the indexing model from the issue text.