[Perf] Windows/x86: 2 Regressions on 6/3/2026 1:30:53 PM +00:00

### Run Information

Name | Value
-- | --
Architecture | x86
OS | Windows 10.0.22631
Queue | ViperWindows
Baseline | [ac695692911547e710e43fa7f6e38546a13504a5](https://github.com/dotnet/runtime/commit/ac695692911547e710e43fa7f6e38546a13504a5)
Compare | [f5f1079c96decf4c77b7fd84664d739218bda08c](https://github.com/dotnet/runtime/commit/f5f1079c96decf4c77b7fd84664d739218bda08c)
Diff | [Diff](https://github.com/dotnet/runtime/compare/ac695692911547e710e43fa7f6e38546a13504a5...f5f1079c96decf4c77b7fd84664d739218bda08c)
Configs | CompilationMode:tiered, RunKind:micro

### Regressions in PerfLabTests.LowLevelPerf

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

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

| 2.52 ms | 2.79 ms | 1.11 | 0.14 | 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 'PerfLabTests.LowLevelPerf*'
```

### PerfLabTests.LowLevelPerf.InterfaceInterfaceMethod

#### 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 | x86
OS | Windows 10.0.22631
Queue | ViperWindows
Baseline | [05af41550d4c764284d03bb8d79a977c5cacba8d](https://github.com/dotnet/runtime/commit/05af41550d4c764284d03bb8d79a977c5cacba8d)
Compare | [f5f1079c96decf4c77b7fd84664d739218bda08c](https://github.com/dotnet/runtime/commit/f5f1079c96decf4c77b7fd84664d739218bda08c)
Diff | [Diff](https://github.com/dotnet/runtime/compare/05af41550d4c764284d03bb8d79a977c5cacba8d...f5f1079c96decf4c77b7fd84664d739218bda08c)
Configs | CompilationMode:tiered, RunKind:micro

### Regressions in System.Buffers.Text.Tests.Base64EncodeDecodeInPlaceTests

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

• [Base64DecodeInPlace - Duration of single invocation]()
• 📝 - [Benchmark Source]()
• [ADX - Test Multi Config Graph]()

| 265.25 ms | 328.90 ms | 1.24 | 0.04 | 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.Buffers.Text.Tests.Base64EncodeDecodeInPlaceTests*'
```

### System.Buffers.Text.Tests.Base64EncodeDecodeInPlaceTests.Base64DecodeInPlace(NumberOfBytes: 200000000)

#### 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)