How to reproduce:
1. Open the attached “IN-31693” project
2. Open the “Window → General → Test Runner” window from the menu
3. Click on the “Run All Tests” button to build and analyse performance
4. Open the “Window → Analysis → Test Report” window
5. View the Sample Group View results for “In_ImmutableLargeStruct_WithInOr” test
Expected result: Execution performance improved at least 8 times using the “in” modifier
Actual result: Barely no performance improvement
Reproducible with: 2020.3.46f1
Fixed in: 2021.3.18f1, 2022.2.9f1, 2023.1.0b5, 2023.2.0a4
Note: Even though, in some versions both with and without “in” modifier
performance results are the same, they’re low and considered as expected