[Perf] Windows/x86: 3 Regressions on 6/25/2026 4:49:37 AM +00:00

### Run Information

Name | Value
-- | --
Architecture | x86
OS | Windows 10.0.22631
Queue | ViperWindows
Baseline | [9c1fdaea7e4595785db31a5a219f66fb7d2a4ec1](https://github.com/dotnet/runtime/commit/9c1fdaea7e4595785db31a5a219f66fb7d2a4ec1)
Compare | [42f3669b3a7f418f571ad63a77b3e7ebf9ee64a8](https://github.com/dotnet/runtime/commit/42f3669b3a7f418f571ad63a77b3e7ebf9ee64a8)
Diff | [Diff](https://github.com/dotnet/runtime/compare/9c1fdaea7e4595785db31a5a219f66fb7d2a4ec1...42f3669b3a7f418f571ad63a77b3e7ebf9ee64a8)
Configs | CompilationMode:tiered, RunKind:micro

### Regressions in System.Collections.CtorFromCollection<Int32>

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

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

| 6.14 μs | 6.88 μs | 1.12 | 0.22 | False | | |
|

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

| 7.33 μs | 7.86 μs | 1.07 | 0.02 | False | | |
|

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

| 2.44 μs | 2.62 μs | 1.07 | 0.00 | False | | |

![graph]()
![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.Collections.CtorFromCollection*'
```

### System.Collections.CtorFromCollection<Int32>.LinkedList(Size: 512)

#### ETL Files

#### Histogram

#### JIT Disasms

### System.Collections.CtorFromCollection<Int32>.SortedSet(Size: 512)

#### ETL Files

#### Histogram

#### JIT Disasms

### System.Collections.CtorFromCollection<Int32>.HashSet(Size: 512)

#### 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 benchmark source in src/benchmarks/micro/libraries/System.Collections/Create/CtorFromCollection.cs and reproduce the filtered benchmark using the provided benchmarks_ci.py command. Compare the listed baseline and test commits and inspect the linked regression report; done means identifying the cause of the three Windows/x86 regressions and restoring or explaining the affected performance.

Written by the indexing model from the issue text.