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Merged
merged 4 commits into from
Jun 11, 2025
Merged

Optimize Dictionary<> allocation #393

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b3571ff
Make `MaterializationContext` readonly struct
SergeiPavlov Jun 10, 2025
bca5958
Optimize GetColumns() usage
SergeiPavlov Jun 10, 2025
1a1ca6f
Optimize VisitConstructorExpression
SergeiPavlov Jun 10, 2025
0bbe562
Remove string.Contains()
SergeiPavlov Jun 10, 2025
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8 changes: 0 additions & 8 deletions Orm/Xtensive.Orm/Core/Extensions/StringExtensions.cs
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Original file line number Diff line number Diff line change
Expand Up @@ -547,13 +547,5 @@ public static string StripRoundBrackets(this string value)
? value
: value.Substring(start - 1, actualLength);
}

internal static bool Contains(this string str, string value, StringComparison comparison)
{
ArgumentNullException.ThrowIfNull(str);
ArgumentNullException.ThrowIfNull(value);

return str.IndexOf(value, comparison) >= 0;
}
}
}
18 changes: 7 additions & 11 deletions Orm/Xtensive.Orm/Orm/Linq/Expressions/Visitors/ExtendedExpressionReplacer.cs
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Expand Up @@ -4,8 +4,6 @@
// Created by: Alexis Kochetov
// Created: 2009.04.27

using System;
using System.Collections.Generic;
using System.Linq.Expressions;
using System.Reflection;
using Xtensive.Orm.Rse.Providers;
Expand Down Expand Up @@ -115,26 +113,24 @@ internal override Expression VisitColumnExpression(ColumnExpression expression)

internal override Expression VisitConstructorExpression(ConstructorExpression expression)
{
var arguments = new List<Expression>();
var bindings = new Dictionary<MemberInfo, Expression>(expression.Bindings.Count);
var nativeBindings = new Dictionary<MemberInfo, Expression>(expression.NativeBindings.Count);
bool recreate = false;
var arguments = new Expression[expression.ConstructorArguments.Count];
int i = 0;
foreach (var argument in expression.ConstructorArguments) {
var result = Visit(argument);
if (result != argument)
recreate = true;
arguments.Add(result);
recreate |= (result != argument);
arguments[i++] = result;
}
foreach (var binding in expression.Bindings) {
var result = Visit(binding.Value);
if (result != binding.Value)
recreate = true;
recreate |= (result != binding.Value);
bindings.Add(binding.Key, result);
}
foreach (var nativeBinding in expression.NativeBindings) {
var result = Visit(nativeBinding.Value);
if (result!=nativeBinding.Value)
recreate = true;
recreate |= (result != nativeBinding.Value);
nativeBindings.Add(nativeBinding.Key, result);
}
if (!recreate)
Expand Down Expand Up @@ -163,4 +159,4 @@ public ExtendedExpressionReplacer(Func<Expression, Expression> replaceDelegate)
providerVisitor = new CompilableProviderVisitor(TranslateExpression);
}
}
}
}
35 changes: 8 additions & 27 deletions Orm/Xtensive.Orm/Orm/Linq/Materialization/MaterializationContext.cs
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Expand Up @@ -10,24 +10,16 @@

namespace Xtensive.Orm.Linq.Materialization
{
internal sealed class MaterializationContext
{
#region Nested type: EntityMappingCache

private struct EntityMappingCache
{
public TypeMapping? SingleItem;
public Dictionary<int, TypeMapping> Items;
}

#endregion
using EntityMappingCache = (TypeMapping? SingleItem, Dictionary<int, TypeMapping> Items);

private readonly EntityMappingCache[] entityMappings;
internal class MaterializationContext(Session session, int entityCount)
{
private readonly EntityMappingCache[] entityMappings = new EntityMappingCache[entityCount];

/// <summary>
/// Gets the session in which materialization is executing.
/// </summary>
public Session Session { get; }
public Session Session => session;

/// <summary>
/// Gets model of current <see cref="DomainModel">domain model.</see>
Expand All @@ -52,12 +44,12 @@ private struct EntityMappingCache
public TypeMapping GetTypeMapping(int entityIndex, TypeInfo approximateType, int typeId, IEnumerable<(ColNum From, ColNum To)> columns)
{
ref var cache = ref entityMappings[entityIndex];
if (cache.SingleItem is TypeMapping result) {
if (cache.SingleItem is { } result) {
return typeId == ResolveTypeToNodeSpecificTypeIdentifier(result.Type)
? result
: throw new ArgumentOutOfRangeException("typeId");
}
if (cache.Items.TryGetValue(typeId, out result))
if (cache.Items?.TryGetValue(typeId, out result) == true)
return result;

var type = TypeIdRegistry[typeId];
Expand All @@ -83,22 +75,11 @@ public TypeMapping GetTypeMapping(int entityIndex, TypeInfo approximateType, int
if (type.Hierarchy.Root.IsLeaf && approximateType==type)
cache.SingleItem = result;
else
cache.Items.Add(typeId, result);
(cache.Items ??= new()).Add(typeId, result);

return result;
}

private int ResolveTypeToNodeSpecificTypeIdentifier(TypeInfo typeInfo) => TypeIdRegistry[typeInfo];

// Constructors

public MaterializationContext(Session session, int entityCount)
{
Session = session;

entityMappings = new EntityMappingCache[entityCount];
for (int i = 0; i < entityMappings.Length; i++)
entityMappings[i] = new() { Items = new Dictionary<int, TypeMapping>() };
}
}
}
25 changes: 6 additions & 19 deletions Orm/Xtensive.Orm/Orm/Linq/Materialization/Materializer.cs
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Expand Up @@ -2,26 +2,13 @@
// This code is distributed under MIT license terms.
// See the License.txt file in the project root for more information.

using System;
using Xtensive.Core;
using Xtensive.Orm.Rse;

namespace Xtensive.Orm.Linq.Materialization
{
internal readonly struct Materializer
{
private readonly Func<RecordSetReader, Session, ParameterContext, object> materializeMethod;

public QueryResult<T> Invoke<T>(RecordSetReader recordSetReader, Session session, ParameterContext parameterContext)
{
var reader = (IMaterializingReader<T>)
materializeMethod.Invoke(recordSetReader, session, parameterContext);
return new QueryResult<T>(reader, session.GetLifetimeToken());
}
namespace Xtensive.Orm.Linq.Materialization;

public Materializer(Func<RecordSetReader,Session,ParameterContext,object> materializeMethod)
{
this.materializeMethod = materializeMethod;
}
}
}
internal readonly struct Materializer(Func<RecordSetReader, Session, ParameterContext, object> materializeMethod)
{
public QueryResult<T> Invoke<T>(RecordSetReader recordSetReader, Session session, ParameterContext parameterContext) =>
new((IMaterializingReader<T>) materializeMethod(recordSetReader, session, parameterContext), session.GetLifetimeToken());
}
17 changes: 8 additions & 9 deletions Orm/Xtensive.Orm/Orm/Linq/Translator.Materialization.cs
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Expand Up @@ -4,9 +4,6 @@
// Created by: Alexis Kochetov
// Created: 2009.05.28

using System;
using System.Collections.Generic;
using System.Linq;
using System.Linq.Expressions;
using System.Reflection;
using Xtensive.Core;
Expand Down Expand Up @@ -34,6 +31,9 @@ internal sealed partial class Translator
private static readonly ParameterExpression Session = Expression.Parameter(typeof(Session), "session");
private static readonly IReadOnlyList<ParameterExpression> TupleReaderSessionParameterContext = [TupleReader, Session, ParameterContext];

private static readonly Expression<Func<Session, int, MaterializationContext>> MaterializationContextCtor =
(s, entityCount) => new MaterializationContext(s, entityCount);

private readonly CompiledQueryProcessingScope compiledQueryScope;

public TranslatedQuery Translate()
Expand Down Expand Up @@ -80,16 +80,17 @@ internal TranslatedQuery Translate(ProjectionExpression projection,
return translatedQuery;
}

private static readonly IReadOnlyList<ColNum> SingleColumn = [0];
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Maybe it's not worth to keep it in a variable. Compiler should be smart enough to do it on its own.

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@SergeiPavlov SergeiPavlov Jun 11, 2025 •
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Why to rely on compiler if it is easy to make it optimal manually?
And we are not sure about the compiler.


private static ProjectionExpression Optimize(ProjectionExpression origin)
{
var originProvider = origin.ItemProjector.DataSource;

var usedColumns = origin.ItemProjector
.GetColumns(ColumnExtractionModes.KeepSegment | ColumnExtractionModes.KeepTypeId | ColumnExtractionModes.OmitLazyLoad)
.ToList();
.GetColumns(ColumnExtractionModes.KeepSegment | ColumnExtractionModes.KeepTypeId | ColumnExtractionModes.OmitLazyLoad);

if (usedColumns.Count == 0)
usedColumns.Add(0);
usedColumns = SingleColumn;
if (usedColumns.Count < origin.ItemProjector.DataSource.Header.Length) {
var resultProvider = new SelectProvider(originProvider, usedColumns);
using var columnMap = new ColumnMap(usedColumns);
Expand Down Expand Up @@ -134,9 +135,7 @@ private Materializer BuildMaterializer(ProjectionExpression projection, IReadOnl
: MaterializationHelper.CreateItemMaterializerMethodInfo.CachedMakeGenericMethodInvoker(elementType);
var itemMaterializer = itemMaterializerFactoryMethod.Invoke(null, materializationInfo.Expression, itemProjector.AggregateType);

Expression<Func<Session, int, MaterializationContext>> materializationContextCtor =
(s, entityCount) => new MaterializationContext(s, entityCount);
var materializationContextExpression = materializationContextCtor
var materializationContextExpression = MaterializationContextCtor
.BindParameters(Session, Expr.Constant(materializationInfo.EntitiesInRow));

Expression body = Expression.Call(
Expand Down