[Perf] Linux/arm64: 1 Regression on 7/17/2026 7:36:43 AM +00:00

### Run Information

Name | Value
-- | --
Architecture | arm64
OS | azurelinux 3.0
Queue | CobaltAzureLinux
Baseline | [4c9e771cbd5e35313cef06c4d7efb55070fd5493](https://github.com/dotnet/runtime/commit/4c9e771cbd5e35313cef06c4d7efb55070fd5493)
Compare | [034f7f5c843988fd82ddfb8369b27c67ab986c86](https://github.com/dotnet/runtime/commit/034f7f5c843988fd82ddfb8369b27c67ab986c86)
Diff | [Diff](https://github.com/dotnet/runtime/compare/4c9e771cbd5e35313cef06c4d7efb55070fd5493...034f7f5c843988fd82ddfb8369b27c67ab986c86)
Configs | CompilationMode:tiered, R2RType:r2r_interpreter, RunKind:micro

### Regressions in System.Numerics.Tests.Perf_VectorOf<Byte>

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

• [SquareRootBenchmark - Duration of single invocation]()
• 📝 - [Benchmark Source]()
• [ADX - Test Multi Config 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.Numerics.Tests.Perf_VectorOf*'
```

### System.Numerics.Tests.Perf_VectorOf<Byte>.SquareRootBenchmark

#### 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 System.Numerics.Tests.Perf_VectorOf.SquareRootBenchmark source at src/benchmarks/micro/libraries/System.Numerics.Vectors/Perf_VectorOfT.cs lines 164-165. Follow the benchmarking workflow and run the provided benchmarks_ci.py command, comparing commits 4c9e771cbd5e35313cef06c4d7efb55070fd5493 and 034f7f5c843988fd82ddfb8369b27c67ab986c86. Done means the arm64 AzureLinux regression is reproduced and its cause and corrective action are established.

Written by the indexing model from the issue text.