Optimize VM hot paths for net10

benchmarks/Neo.VM.Benchmarks/Benchmarks_VMHotPaths.cs

@@ -0,0 +1,189 @@
+// Copyright (C) 2015-2026 The Neo Project.
+//
+// Benchmarks_VMHotPaths.cs file belongs to the neo project and is free
+// software distributed under the MIT software license, see the
+// accompanying file LICENSE in the main directory of the
+// repository or http://www.opensource.org/licenses/mit-license.php
+// for more details.
+//
+// Redistribution and use in source and binary forms with or without
+// modifications are permitted.
+
+using BenchmarkDotNet.Attributes;
+using Neo.VM.Types;
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using VMArray = Neo.VM.Types.Array;
+
+namespace Neo.VM.Benchmarks;
+
+public class Benchmarks_ArrayBuild
+{
+    [Params(1, 8, 32, 256, 1024)]
+    public int N { get; set; }
+
+    private static readonly StackItem Item = StackItem.Null;
+
+    [Benchmark]
+    public VMArray BuildWithListFill()
+    {
+        var referenceCounter = new ReferenceCounter();
+        var items = new List<StackItem>(N);
+        for (int i = 0; i < N; i++)
+            items.Add(Item);
+        return new VMArray(referenceCounter, items);
+    }
+
+    [Benchmark]
+    public VMArray BuildWithArrayFill()
+    {
+        var referenceCounter = new ReferenceCounter();
+        var itemArray = new StackItem[N];
+        System.Array.Fill(itemArray, Item);
+        return new VMArray(referenceCounter, itemArray);
+    }
+}
+
+public class Benchmarks_MapSubItems
+{
+    [Params(1, 8, 32, 256, 1024)]
+    public int N { get; set; }
+
+    private Map _map = null!;
+
+    [GlobalSetup]
+    public void Setup()
+    {
+        _map = new Map();
+        for (int i = 0; i < N; i++)
+            _map[new Integer(i)] = new Integer(i + 1);
+    }
+
+    [Benchmark]
+    public int EnumerateYield()
+    {
+        int count = 0;
+        foreach (var _ in SubItemsYield(_map))
+            count++;
+        return count;
+    }
+
+    [Benchmark]
+    public int EnumerateConcat()
+    {
+        int count = 0;
+        foreach (var _ in SubItemsConcat(_map))
+            count++;
+        return count;
+    }
+
+    private static IEnumerable<StackItem> SubItemsYield(Map map)
+    {
+        foreach (var key in map.Keys)
+            yield return key;
+        foreach (var value in map.Values)
+            yield return value;
+    }
+
+    private static IEnumerable<StackItem> SubItemsConcat(Map map) => map.Keys.Concat(map.Values);
+}
+
+public class Benchmarks_ListCopy
+{
+    private const int SourceCount = 4096;
+
+    [Params(1, 8, 32, 256, 1024, 2048)]
+    public int CopyCount { get; set; }
+
+    private List<StackItem> _source = null!;
+    private List<StackItem> _target = null!;
+
+    [GlobalSetup]
+    public void Setup()
+    {
+        _source = new List<StackItem>(SourceCount);
+        for (int i = 0; i < SourceCount; i++)
+            _source.Add(StackItem.Null);
+        _target = new List<StackItem>(CopyCount);
+    }
+
+    [Benchmark]
+    public int AddRangeSkip()
+    {
+        _target.Clear();
+        _target.AddRange(_source.Skip(_source.Count - CopyCount));
+        return _target.Count;
+    }
+
+    [Benchmark]
+    public int ManualLoop()
+    {
+        _target.Clear();
+        int start = _source.Count - CopyCount;
+        for (int i = start; i < _source.Count; i++)
+            _target.Add(_source[i]);
+        return _target.Count;
+    }
+}
+
+public class Benchmarks_InstructionAdvance
+{
+    [Params(1024, 4096, 16384)]
+    public int InstructionCount { get; set; }
+
+    private Script _script = null!;
+    private ExecutionContext _context = null!;
+
+    [GlobalSetup]
+    public void Setup()
+    {
+        var bytes = new byte[InstructionCount];
+        System.Array.Fill(bytes, (byte)OpCode.PUSH0);
+        _script = new Script(bytes);
+        _context = new ExecutionContext(_script, 0, new ReferenceCounter());
+    }
+
+    [IterationSetup]
+    public void IterationSetup()
+    {
+        WarmInstructionCache();
+        _context.InstructionPointer = 0;
+    }
+
+    [Benchmark]
+    public Instruction? AdvanceWithMoveNext()
+    {
+        Instruction? last = null;
+        while (true)
+        {
+            last = _context.CurrentInstruction ?? Instruction.RET;
+            if (!_context.MoveNext()) break;
+        }
+        return last;
+    }
+
+    [Benchmark]
+    public Instruction? AdvanceWithPointer()
+    {
+        Instruction? last = null;
+        while (true)
+        {
+            var current = _context.CurrentInstruction;
+            if (current is null) break;
+            last = current;
+            _context.InstructionPointer += current.Size;
+        }
+        return last;
+    }
+
+    private void WarmInstructionCache()
+    {
+        while (true)
+        {
+            var current = _context.CurrentInstruction;
+            if (current is null) break;
+            _context.InstructionPointer += current.Size;
+        }
+    }
+}

src/Neo.VM/ExecutionEngine.cs

@@ -144,7 +144,8 @@ protected internal void ExecuteNext()
             try
             {
                 ExecutionContext context = CurrentContext!;
-                Instruction instruction = context.CurrentInstruction ?? Instruction.RET;
+                Instruction? currentInstruction = context.CurrentInstruction;
+                Instruction instruction = currentInstruction ?? Instruction.RET;
                 PreExecuteInstruction(instruction);
 #if VMPERF
                 Console.WriteLine("op:["
@@ -163,7 +164,8 @@ protected internal void ExecuteNext()
                     JumpTable.ExecuteThrow(this, ex.Message);
                 }
                 PostExecuteInstruction(instruction);
-                if (!isJumping) context.MoveNext();
+                if (!isJumping && currentInstruction != null)
+                    context.InstructionPointer += instruction.Size;
                 isJumping = false;
             }
             catch (Exception e)