Restore `BitmapBuffer.AsSpan` and add `AggressiveInlining`

fixes 9a5a75e5b and 7ab2ca6b8

src/BizHawk.Bizware.Graphics/BitmapBuffer.cs

@@ -6,6 +6,7 @@ using System.Drawing;
 using System.Drawing.Drawing2D;
 using System.Drawing.Imaging;
 using System.IO;
+using System.Runtime.CompilerServices;
 using System.Runtime.InteropServices;
 
 using BizHawk.Common.CollectionExtensions;
@@ -36,6 +37,11 @@ namespace BizHawk.Bizware.Graphics
 		private GCHandle CurrLockHandle;
 		private BitmapData CurrLock;
 
+		/// <summary>same as <see cref="Pixels"/> (<see cref="PixelFormat.Format32bppArgb">A8R8G8B8</see>)</summary>
+		[MethodImpl(MethodImplOptions.AggressiveInlining)]
+		public Span<int> AsSpan()
+			=> Pixels;
+
 		/// <exception cref="InvalidOperationException">already locked</exception>
 		/// <remarks>TODO add read/write semantic, for wraps</remarks>
 		public BitmapData LockBits()
@@ -221,7 +227,7 @@ namespace BizHawk.Bizware.Graphics
 		}
 
 		public BitmapBuffer Copy()
-			=> new(width: Width, height: Height, pixels: Pixels.AsSpan().ToArray());
+			=> new(width: Width, height: Height, pixels: AsSpan().ToArray());
 
 		/// <remarks>TODO surely there's a better implementation --yoshi</remarks>
 		public BitmapBuffer Copy(Rectangle region)
@@ -543,7 +549,7 @@ namespace BizHawk.Bizware.Graphics
 		}
 
 		public bool SequenceEqual(BitmapBuffer other)
-			=> Width == other.Width && Height == other.Height && Pixels.SequenceEqual(other.Pixels);
+			=> Width == other.Width/* && Height == other.Height*/ && AsSpan().SequenceEqual(other.AsSpan());
 
 		/// <summary>
 		/// Dumps this BitmapBuffer to a new System.Drawing.Bitmap

src/BizHawk.Common/Extensions/CollectionExtensions.cs

@@ -322,6 +322,7 @@ namespace BizHawk.Common.CollectionExtensions
 			return true;
 		}
 
+		[MethodImpl(MethodImplOptions.AggressiveInlining)]
 		public static bool SequenceEqual<T>(this T[] a, ReadOnlySpan<T> b) where T : IEquatable<T> => a.AsSpan().SequenceEqual(b);
 	}
 }