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Optimize ExpressionMaterializer.CreateEntity() #486

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Merged
SergeiPavlov merged 2 commits into from
May 13, 2026
Merged

Optimize ExpressionMaterializer.CreateEntity() #486

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b910f17
Optimize `ExpressionMaterializer.CreateEntity()`
SergeiPavlov May 12, 2026
e38ef1d
Simplify
SergeiPavlov May 12, 2026
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7 changes: 3 additions & 4 deletions Orm/Xtensive.Orm/Orm/Linq/Materialization/ExpressionMaterializer.cs
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Original file line number Diff line number Diff line change
Expand Up @@ -6,6 +6,7 @@

using System.Linq.Expressions;
using System.Reflection;
using System.Runtime.InteropServices;
using Xtensive.Core;
using Xtensive.Linq;
using Xtensive.Orm.Internals;
Expand Down Expand Up @@ -384,10 +385,8 @@ internal protected override Expression VisitEntityExpression(EntityExpression ex
/// <exception cref="InvalidOperationException">Unable to materialize Entity.</exception>
private Expression CreateEntity(IEntityExpression expression, Expression tupleExpression)
{
if (!entityRegistry.TryGetValue(expression, out var index)) {
index = entityRegistry.Count;
entityRegistry.Add(expression, index);
}
ref var indexRef = ref CollectionsMarshal.GetValueRefOrAddDefault(entityRegistry, expression, out var exists);
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@snaumenko-st snaumenko-st May 12, 2026 •
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IMHO too dangerous. And my previous benchmarks haven't indicated the significant performance boost. So probably it's not worth it

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@SergeiPavlov SergeiPavlov May 12, 2026

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Why can it be dangerous?
.NET implementation of Dictionary.TryAdd() uses it inside

And here is some benchmark showing the performance gain https://matthewcrews.com/blog/2022/03/performance-of-key-value-lookups-types/

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@snaumenko-st snaumenko-st May 13, 2026

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It's easy to use it wrong way. That's it

var index = exists ? indexRef : (indexRef = entityRegistry.Count - 1);

if (itemMaterializationContextParameter==null)
throw new InvalidOperationException(
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