Convert funceval to UCO pattern

[am11]

Built on top of #126542.

Last part of #123864 before the final cleanups.

[am11]

cc @jkotas, @janvorli

Tested it with this program in VSCode:

Program.cs

using System;
using System.Diagnostics;
using System.Runtime.InteropServices;

// Test various funceval scenarios that exercise DoNormalFuncEval
var dt = new DateTime(2026, 4, 12);
var list = new System.Collections.Generic.List<int> { 1, 2, 3 };
var str = "hello funceval";
int x = 42;
double pi = 3.14;
bool flag = true;
var dict = new System.Collections.Generic.Dictionary<string, int> { ["one"] = 1, ["two"] = 2 };
var arr = new int[] { 10, 20, 30 };
object boxed = 99;
var guid = Guid.NewGuid();
var span = "hello".AsSpan(); // not directly evaluable but interesting
var tuple = (Name: "Alice", Age: 30);

// Breakpoint here - then evaluate expressions in Watch/Immediate window:
//
// === Instance methods on value types (boxes 'this') ===
//   dt.ToString()              → value type instance method
//   dt.AddDays(1)              → value type method with arg, returns value type
//   guid.ToString()            → Guid.ToString()
//   pi.ToString("F1")          → double method with string arg
//   tuple.ToString()           → ValueTuple instance method
//
// === Instance methods on ref types ===
//   str.Length                  → string property (handle-based 'this')
//   str.Contains("func")       → string method with string arg
//   str.Substring(6, 4)        → string method with two int args
//   list.Count                 → generic ref type property
//   list.Contains(2)           → generic method with boxed int arg
//   list[0]                    → indexer (get_Item)
//   dict["one"]                → dictionary indexer
//   dict.ContainsKey("two")    → dictionary method
//   arr.Length                 → array property
//
// === Primitive 'this' (box + call) ===
//   x.ToString()               → int.ToString()
//   x.GetType()                → int.GetType() returns System.Int32
//   flag.ToString()            → bool.ToString()
//   x.CompareTo(10)            → int.CompareTo(int)
//
// === Static methods (this = null) ===
//   string.Concat("a", "b")   → static with ref type args
//   string.IsNullOrEmpty("")   → static with ref type arg
//   int.Parse("123")           → static returning primitive
//   Math.Max(3, 7)             → static with two primitive args
//   DateTime.UtcNow            → static property returning value type
//   Environment.ProcessId      → static property returning int
//   RuntimeInformation.FrameworkDescription → static property returning string
//   Guid.NewGuid()             → static method returning value type
//   Convert.ToInt32("42")      → static with string arg returning int
//
// === NEW_OBJECT (constructor) ===
//   new DateTime(2000, 1, 1)   → value type ctor with primitive args
//   new List<int>()            → ref type default ctor
//   new string('x', 5)        → string ctor with char + int
//   new object()               → simplest ctor
//
// === Boxed object ===
//   boxed.ToString()           → call on boxed int (ELEMENT_TYPE_OBJECT)
//   boxed.GetType()            → GetType on boxed int
//
Debugger.Break();

Console.WriteLine($"dt={dt}, list.Count={list.Count}, str={str}, x={x}");
Console.WriteLine($"dict={dict.Count}, arr={arr.Length}, guid={guid}, pi={pi}, flag={flag}");

launch.json

{
    "version": "0.2.0",
    "configurations": [
        {
            "name": "funceval-test (branch)",
            "type": "coreclr",
            "request": "launch",
            "program": "c:\\temp\\runtime\\artifacts\\bin\\testhost\\net11.0-windows-Release-x64\\dotnet.exe",
            "args": ["exec", "C:\\temp\\funceval-test\\bin\\Debug\\net11.0\\funceval-test.dll"],
            "cwd": "${workspaceFolder}",
            "stopAtEntry": false,
            "env": {
                "DOTNET_ROOT": "c:\\temp\\runtime\\artifacts\\bin\\testhost\\net11.0-windows-Release-x64"
            }
        },
        {
            "name": "funceval-test (main)",
            "type": "coreclr",
            "request": "launch",
            "program": "c:\\temp\\runtime\\runtime2\\artifacts\\bin\\testhost\\net11.0-windows-Release-x64\\dotnet.exe",
            "args": ["exec", "C:\\temp\\funceval-test\\bin\\Debug\\net11.0\\funceval-test.dll"],
            "cwd": "${workspaceFolder}",
            "stopAtEntry": false,
            "env": {
                "DOTNET_ROOT": "c:\\temp\\runtime\\runtime2\\artifacts\\bin\\testhost\\net11.0-windows-Release-x64"
            }
        }
    ]
}

Results match main branch:

PR	Main

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[jkotas]

Built on top of #126542.

Does it depend on any of the changes in #126542 given that it just calls the public MethodInfo.Invoke API?

[am11]

Built on top of #126542.

Does it depend on any of the changes in #126542 given that it just calls the public MethodInfo.Invoke API?

#126542 moved InvokeMethod to managed and this is tested end to end that way. I can cherry-pick ffa8a51 on main if we want this one to go in first.

[jkotas]

I am not sure which one will go first. If these changes are independent, it would make more sense to submit them as independent PRs.

[jkotas]

One of the Microsoft maintainers will have to run internal VS debugger tests on this before it gets merged.

[am11]

Failures are known, the new one is unrelated deadlettered leg. Results still match before/after #126809 (comment)

[janvorli]

Let me run the private diagnostic tests with this change.