fix: Rectangle.Intersect

[7aGiven]

• I confirm that I am the author of this code and release it to the FNA project under the Ms-PL license. This contribution does not contain code from other sources, including code generated by a Large Language Model ("AI").

Test Case:

using Microsoft.Xna.Framework;
using System;

namespace RenderTargetTest
{
    internal class Program
    {
        static void Main(string[] args)
        {
            var r1 = new Rectangle(0, 831, -2, 514);
            var r2 = new Rectangle(-5, 831, 1497, 2520);

            Rectangle r;
            Rectangle.Intersect(ref r1, ref r2, out r);

            Console.WriteLine(r);
        }
    }
}

XNA output:

{X:0 Y:0 Width:0 Height:0}

FNA output:

{X:0 Y:831 Width:-2 Height:514}

[7aGiven]

link #680

[7aGiven]

For ensure all is inline

.NET 8.0.30 (8.0.30, 8.0.3026.36720), X64 RyuJIT x86-64-v3 (Job: DefaultJob)

; Microsoft.Xna.Framework.Rectangle.Intersect1(Microsoft.Xna.Framework.Rectangle ByRef, Microsoft.Xna.Framework.Rectangle ByRef, Microsoft.Xna.Framework.Rectangle ByRef)
       push      rsi
       push      rbx
       vzeroupper
       mov       eax,[rcx]
       mov       r10d,eax
       add       r10d,[rcx+8]
       mov       r9d,[rdx]
       mov       r11d,r9d
       add       r11d,[rdx+8]
       cmp       r10d,r11d
       cmovg     r10d,r11d
       mov       r11d,[rcx+4]
       mov       ebx,r11d
       add       ebx,[rcx+0C]
       mov       ecx,[rdx+4]
       mov       esi,ecx
       add       esi,[rdx+0C]
       cmp       ebx,esi
       cmovg     ebx,esi
       cmp       eax,r9d
       cmovl     eax,r9d
       cmp       r11d,ecx
       cmovl     r11d,ecx
       cmp       eax,r10d
       jge       short M01_L00
       cmp       r11d,ebx
       jge       short M01_L00
       sub       r10d,eax
       sub       ebx,r11d
       mov       [r8],eax
       mov       [r8+4],r11d
       mov       [r8+8],r10d
       mov       [r8+0C],ebx
       pop       rbx
       pop       rsi
       ret
M01_L00:
       vxorps    xmm0,xmm0,xmm0
       vmovdqu   xmmword ptr [r8],xmm0
       pop       rbx
       pop       rsi
       ret
; Total bytes of code 114