System.Numerics work planned for .NET 7

[jeffhandley]

This issue captures the planned work for .NET 7. This list is expected to change throughout the release cycle according to ongoing planning and discussions, with possible additions and subtractions to the scope.

Summary

During .NET 7, we will continue work on the Generic Math feature set, which is tracked in its own epic (#63548). Additionally, we will invest in quality, enhancements and new APIs, plus performance improvements. This is an ambitious set of work, so it's likely that several of the items below will be pushed out beyond .NET 7.

Planned for .NET 7

Quality

• Incorrect results of right shifting huge BigIntegers #65633
• Update the XML docs for IComparisonOperators and implementing types #64463
• BigInteger.Parse returns bogus value for exponents above 1000 #17296

Enhancements / New APIs

• Extend System.Runtime.InteropServices.NFloat so it can replace the Xamarin in-box nfloat for .NET 7 #63801
• System.Numerics.Vector2.Equals doesn't use float.Equals in Equals implementation  #58853
• IBinaryNumber interface does not have an "AllBitsSet" property  #60882

Performance

• Regressions in System.Numerics.Tests.Perf_BigInteger #60293
• Math/MathF.Truncate isn't an intrinsic and results in inefficient codegen #56931

Backlog (roughly in priority order)

• [Perf -1,517%] System.Numerics.Tests.Perf_Vector2.DistanceBenchmark #50939
• Make Math/MathF.Sign inlineable for floating point data #57413
• Math.Round(value, digits, mode) does not return the correct result #1643
• Conditional format specifier and negative zero #13712
• Investigate the behavior difference in System.Runtime.Numeric when running on desktop #19874
• IndexOutOfRangeException in System.Numerics.Vector<T>(array) Where array Size < 32 Bytes #24174
• double.TryParse of "0,12" incorrectly returns true with result of 0.12. #25868
• API Proposal: Add blittable Color to System.Numerics #48615
• Microbenchmark System.Numerics.Tests.Perf_BitOperations.PopCount_ulongis 464 % slower on Wasm #41454

[dotnet-issue-labeler]

I couldn't figure out the best area label to add to this issue. If you have write-permissions please help me learn by adding exactly one area label.

[ghost]

Tagging subscribers to this area: @tannergooding, @pgovind
See info in area-owners.md if you want to be subscribed.

Issue Details

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There are several edge case bugs that have been observed in Numerics/Intrinsics that can be addressed for more reliable results.

Work Items

• Math.Round(value, digits, mode) does not return the correct result #1643
• Conditional format specifier and negative zero #13712
• BigInteger.Parse returns bogus value for exponents above 1000 #17296
• Investigate the behavior difference in System.Runtime.Numeric when running on desktop #19874
• IndexOutOfRangeException in System.Numerics.Vector<T>(array) Where array Size < 32 Bytes #24174
• double.TryParse of "0,12" incorrectly returns true with result of 0.12. #25868
• Bug: Incorrect result for 32-bit right shift of specific negative values in BigInteger #27358

Author:	jeffhandley
Assignees:	jeffhandley, pgovind, tannergooding
Labels:	area-System.Numerics
Milestone:	-

[danmoseley]

Seems like a great User Story?

[jeffhandley]

Yep; thanks. I meant to apply the label; thanks for recognizing it was missing. Done.