[Perf] Linux/x64: 2 Regressions on 6/1/2026 8:05:47 AM +00:00

### Run Information

Name | Value
-- | --
Architecture | x64
OS | ubuntu 22.04
Queue | ViperUbuntu
Baseline | [f2d5042ceaea5642bac6bde8a1a5765afcbf2ef4](https://github.com/dotnet/runtime/commit/f2d5042ceaea5642bac6bde8a1a5765afcbf2ef4)
Compare | [480e3c83373f82f57c35a44d6c4215e7900e6abd](https://github.com/dotnet/runtime/commit/480e3c83373f82f57c35a44d6c4215e7900e6abd)
Diff | [Diff](https://github.com/dotnet/runtime/compare/f2d5042ceaea5642bac6bde8a1a5765afcbf2ef4...480e3c83373f82f57c35a44d6c4215e7900e6abd)
Configs | AOT:true, CompilationMode:wasm, RunKind:micro

### Regressions in System.Memory.Span<Char>

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

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

| 2.49 ns | 175.00 ns | 70.17 | 0.43 | 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
python3 .\performance\scripts\benchmarks_ci.py -f net8.0 --filter 'System.Memory.Span*'
```

### System.Memory.Span<Char>.CopyToSame(Size: 33)

#### 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 | ubuntu 22.04
Queue | ViperUbuntu
Baseline | [f2d5042ceaea5642bac6bde8a1a5765afcbf2ef4](https://github.com/dotnet/runtime/commit/f2d5042ceaea5642bac6bde8a1a5765afcbf2ef4)
Compare | [480e3c83373f82f57c35a44d6c4215e7900e6abd](https://github.com/dotnet/runtime/commit/480e3c83373f82f57c35a44d6c4215e7900e6abd)
Diff | [Diff](https://github.com/dotnet/runtime/compare/f2d5042ceaea5642bac6bde8a1a5765afcbf2ef4...480e3c83373f82f57c35a44d6c4215e7900e6abd)
Configs | AOT:true, CompilationMode:wasm, RunKind:micro

### Regressions in Inlining.InlineGCStruct

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

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

| 4.27 ns | 175.00 ns | 41.00 | 0.31 | 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
python3 .\performance\scripts\benchmarks_ci.py -f net8.0 --filter 'Inlining.InlineGCStruct*'
```

### Inlining.InlineGCStruct.WithoutFormat

#### 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 two benchmark sources named in the report: src/benchmarks/micro/libraries/System.Memory/Span.cs and src/benchmarks/micro/runtime/Inlining/InlineGCStruct.cs. Run the provided benchmarks using scripts/benchmarks_ci.py, then compare the baseline and compare commits and consult the profiling and benchmarking workflow docs. Done means identifying and addressing the regressions, with benchmark results showing the affected cases no longer regress.

Written by the indexing model from the issue text.