[Perf] Linux/x64: 1 Regression on 9/1/2026 12:38:34 PM +00:00

### Run Information

Name | Value
-- | --
Architecture | x64
OS | ubuntu 22.04
Queue | ViperUbuntu
Baseline | [bdcba57531224815fbbc0fbb5ee23a1d3876d43a](https://github.com/dotnet/runtime/commit/bdcba57531224815fbbc0fbb5ee23a1d3876d43a)
Compare | [f00a5ba2dde9f648bcd9ac77411d1a8596449303](https://github.com/dotnet/runtime/commit/f00a5ba2dde9f648bcd9ac77411d1a8596449303)
Diff | [Diff](https://github.com/dotnet/runtime/compare/bdcba57531224815fbbc0fbb5ee23a1d3876d43a...f00a5ba2dde9f648bcd9ac77411d1a8596449303)
Configs | CompilationMode:wasm, RunKind:micro, RuntimeType:coreclr

### Regressions in System.Numerics.Tests.Perf_BigInteger

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

• [ModPow - 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
python3 .\performance\scripts\benchmarks_ci.py -f net8.0 --filter 'System.Numerics.Tests.Perf_BigInteger*'
```

### System.Numerics.Tests.Perf_BigInteger.ModPow(arguments: 16,16,16 bits)

#### 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 linked benchmark source in dotnet/performance/src/benchmarks/micro/libraries/System.Runtime.Numerics/Perf.BigInteger.cs and the benchmarking workflow documentation. Run the provided benchmarks_ci.py command for System.Numerics.Tests.Perf_BigInteger, then compare the baseline and regression reports for ModPow. Done means reproducing the slowdown and identifying or resolving its cause with verified performance results.

Written by the indexing model from the issue text.