dotnet/roslyn

Favor `Kind` check over type checking when appropriate

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#69,048 opened on Jul 15, 2023

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 (0 comments) (0 reactions) (0 assignees)C# (4,257 forks)batch import
Area-CompilersArea-Performancehelp wanted

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Description

image

Type checking here is 2.8% of CPU time. A good portion of it happens for symbols.

Would the following be more efficient?

if (symbol.Kind == SymbolKind.KindWeLookFor)
{
    return Unsafe.As<SymbolTypeToCastTo>(symbol);
}

Contributor guide

Research direction
Find the type checking in the hot path and replace it with a Kind check using Unsafe.As.
Tech stack
csharp
Domain
backend
Issue type
Performance
DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.
1
Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.
Under 1 hour
Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.
Fresh
ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.
Clear
Prerequisites
C#
Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.
80