Update Constants with cached type arrays in order to avoid allocations when patching plugins via DirectCallMethod

Author: scorteanucosmin

src/Common/Constants.cs

@@ -1,4 +1,5 @@
-using System.IO;
+using System;
+using System.IO;
 using System.Text;
 using System.Text.RegularExpressions;
 using Oxide.Core;
@@ -42,5 +43,10 @@ internal static class Constants
         internal static readonly string IncludePath = Path.Combine(Interface.Oxide.PluginDirectory, "include");
         internal static readonly string CSharpPath = Path.Combine(Interface.Oxide.ExtensionDirectory, "Oxide.CSharp.dll");
         internal static readonly string MscorlibPath = Path.Combine(Interface.Oxide.ExtensionDirectory, "mscorlib.dll");
+
+        internal static readonly Type[] StringGetLengthTypeArray = [];
+        internal static readonly Type[] StringGetCharsTypeArray = [typeof(int)];
+        internal static readonly Type[] StringIsNullOrEmptyTypeArray = [typeof(string)];
+        internal static readonly Type[] StringEqualsTypeArray = [typeof(string)];
     }
 }

src/DirectCallMethod.cs

@@ -23,9 +23,9 @@ public class DirectCallMethod
         private readonly MethodReference _isNullOrEmpty;
         private readonly MethodReference _stringEquals;
         private readonly string _hookAttribute;
-        private readonly Dictionary<Instruction, Node> _jumpToEdgePlaceholderTargets = new();
-        private readonly List<Instruction> _jumpToEndPlaceholders = new();
-        private readonly Dictionary<string, MethodDefinition> _hookMethods = new();
+        private readonly Dictionary<Instruction, Node> _jumpToEdgePlaceholderTargets;
+        private readonly List<Instruction> _jumpToEndPlaceholders;
+        private readonly Dictionary<string, MethodDefinition> _hookMethods;
 
         public DirectCallMethod(ModuleDefinition module, TypeDefinition type, AssemblyDefinition baseAssembly)
         {
@@ -46,6 +46,10 @@ public DirectCallMethod(ModuleDefinition module, TypeDefinition type, AssemblyDe
 
             _hookAttribute = typeof(HookMethodAttribute).FullName;
 
+            _jumpToEdgePlaceholderTargets = new Dictionary<Instruction, Node>();
+            _jumpToEndPlaceholders = new List<Instruction>();
+            _hookMethods = new Dictionary<string, MethodDefinition>();
+
             // Copy method definition from base class
             ModuleDefinition baseModule = baseAssembly.MainModule;
             TypeDefinition baseType = module.ImportReference(baseAssembly.MainModule.GetType("Oxide.Plugins.CSharpPlugin")).Resolve();