[Perf] Windows/x64: 2 Improvements on 3/19/2026 3:35:34 PM +00:00

### Run Information

Name | Value
-- | --
Architecture | x64
OS | Windows 10.0.22631
Queue | ViperWindows
Baseline | [12cdada8d6a5d342c3d0647b3c2f5b1d36c08821](https://github.com/dotnet/runtime/commit/12cdada8d6a5d342c3d0647b3c2f5b1d36c08821)
Compare | [37c96934b3fdeeceae7bfd730c736c5667e32c7c](https://github.com/dotnet/runtime/commit/37c96934b3fdeeceae7bfd730c736c5667e32c7c)
Diff | [Diff](https://github.com/dotnet/runtime/compare/12cdada8d6a5d342c3d0647b3c2f5b1d36c08821...37c96934b3fdeeceae7bfd730c736c5667e32c7c)
Configs | CompilationMode:tiered, RunKind:micro

### Improvements in System.Memory.ReadOnlySpan

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

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

| 11.14 ns | 9.16 ns | 0.82 | 0.02 | False | | |

![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.Memory.ReadOnlySpan*'
```

### System.Memory.ReadOnlySpan.IndexOfString(input: "Hello WorldbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbareallyreallylongHello WorldbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbareallyreallylongHello Worldbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbareallyreallylong!xyz", value: "~", comparisonType: Ordinal)

#### 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)

---

### Run Information

Name | Value
-- | --
Architecture | x64
OS | Windows 10.0.22631
Queue | ViperWindows
Baseline | [c05c6a486d04f11249b5adf187dce49d98a53566](https://github.com/dotnet/runtime/commit/c05c6a486d04f11249b5adf187dce49d98a53566)
Compare | [37c96934b3fdeeceae7bfd730c736c5667e32c7c](https://github.com/dotnet/runtime/commit/37c96934b3fdeeceae7bfd730c736c5667e32c7c)
Diff | [Diff](https://github.com/dotnet/runtime/compare/c05c6a486d04f11249b5adf187dce49d98a53566...37c96934b3fdeeceae7bfd730c736c5667e32c7c)
Configs | CompilationMode:tiered, RunKind:micro

### Improvements in System.Numerics.Tensors.Tests.Perf_FloatingPointTensorPrimitives<Single>

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

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

| 15.72 ns | 7.46 ns | 0.47 | 0.35 | False | | |

![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.Numerics.Tensors.Tests.Perf_FloatingPointTensorPrimitives*'
```

### System.Numerics.Tensors.Tests.Perf_FloatingPointTensorPrimitives<Single>.Round(BufferLength: 128)

#### 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)