dotnet/runtime

Improve APIs for Intel string handling intrinsics

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#957 opened on Jun 13, 2018

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 (14 comments) (2 reactions) (0 assignees)C# (5,445 forks)batch import
arch-x64area-System.Runtime.Intrinsicshelp wanted

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Description

See https://github.com/dotnet/coreclr/pull/17637 for some discussion and context. The fundamental issues revolve around how much of the behavior should be controlled by enums passed into the intrinsic method, versus separating the different behaviors into differently-named intrinsics.

The current API includes both StringComparisonMode (https://github.com/dotnet/corefx/blob/master/src/System.Runtime.Intrinsics/ref/System.Runtime.Intrinsics.cs#L864) and ResultsFlag (https://github.com/dotnet/corefx/blob/master/src/System.Runtime.Intrinsics/ref/System.Runtime.Intrinsics.cs#L875).

Some of the open questions are:

  • Should the ResultsFlag, which determines the comparison results for which a true result is returned, become part of the method name?
  • How should these be named? According to the instruction documentation (e.g. CFlag, as in the current API), or something more descriptive like CompareNonZeroMask?
  • Should these be combined into a single enum or remain separate?

Contributor guide

Research direction
Review the linked PR (dotnet/coreclr#17637) for context, examine the current API design for Intel string handling intrinsics including StringComparisonMode and ResultsFlag, and propose solutions to the open questions about naming and combining enums.
Tech stack
csharp
Domain
backend api design
Issue type
Feature
DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.
3
Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.
1-2 days
Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.
Active
ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.
Clear
Prerequisites
C#.NET runtime intrinsics
Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.
20