Simplify some non-generic CompareTo methods (#101545)

* Simplify some CompareTo methods

* Simplify some more CompareTo methods

* Revert "Simplify some more CompareTo methods"

This reverts commit 5dab47d.

* Use DateTime.CompareTo in DatetimeOffset

Author: lilinus

src/libraries/System.Private.CoreLib/src/System/DateTimeOffset.cs

@@ -571,26 +571,16 @@ public static int Compare(DateTimeOffset first, DateTimeOffset second) =>
         int IComparable.CompareTo(object? obj)
         {
             if (obj == null) return 1;
-            if (!(obj is DateTimeOffset))
+            if (obj is not DateTimeOffset other)
             {
                 throw new ArgumentException(SR.Arg_MustBeDateTimeOffset);
             }
 
-            DateTime objUtc = ((DateTimeOffset)obj).UtcDateTime;
-            DateTime utc = UtcDateTime;
-            if (utc > objUtc) return 1;
-            if (utc < objUtc) return -1;
-            return 0;
+            return DateTime.Compare(UtcDateTime, other.UtcDateTime);
         }
 
-        public int CompareTo(DateTimeOffset other)
-        {
-            DateTime otherUtc = other.UtcDateTime;
-            DateTime utc = UtcDateTime;
-            if (utc > otherUtc) return 1;
-            if (utc < otherUtc) return -1;
-            return 0;
-        }
+        public int CompareTo(DateTimeOffset other) =>
+            DateTime.Compare(UtcDateTime, other.UtcDateTime);
 
         // Checks if this DateTimeOffset is equal to a given object. Returns
         // true if the given object is a boxed DateTimeOffset and its value

src/libraries/System.Private.CoreLib/src/System/Guid.cs

@@ -958,68 +958,11 @@ public int CompareTo(object? value)
             {
                 return 1;
             }
-            if (!(value is Guid))
+            if (value is not Guid other)
             {
                 throw new ArgumentException(SR.Arg_MustBeGuid, nameof(value));
             }
-            Guid g = (Guid)value;
-
-            if (g._a != _a)
-            {
-                return GetResult((uint)_a, (uint)g._a);
-            }
-
-            if (g._b != _b)
-            {
-                return GetResult((uint)_b, (uint)g._b);
-            }
-
-            if (g._c != _c)
-            {
-                return GetResult((uint)_c, (uint)g._c);
-            }
-
-            if (g._d != _d)
-            {
-                return GetResult(_d, g._d);
-            }
-
-            if (g._e != _e)
-            {
-                return GetResult(_e, g._e);
-            }
-
-            if (g._f != _f)
-            {
-                return GetResult(_f, g._f);
-            }
-
-            if (g._g != _g)
-            {
-                return GetResult(_g, g._g);
-            }
-
-            if (g._h != _h)
-            {
-                return GetResult(_h, g._h);
-            }
-
-            if (g._i != _i)
-            {
-                return GetResult(_i, g._i);
-            }
-
-            if (g._j != _j)
-            {
-                return GetResult(_j, g._j);
-            }
-
-            if (g._k != _k)
-            {
-                return GetResult(_k, g._k);
-            }
-
-            return 0;
+            return CompareTo(other);
         }
 
         public int CompareTo(Guid value)

src/libraries/System.Private.CoreLib/src/System/Runtime/InteropServices/NFloat.cs

@@ -780,19 +780,7 @@ public int CompareTo(object? obj)
         {
             if (obj is NFloat other)
             {
-                if (_value < other._value) return -1;
-                if (_value > other._value) return 1;
-                if (_value == other._value) return 0;
-
-                // At least one of the values is NaN.
-                if (NativeType.IsNaN(_value))
-                {
-                    return NativeType.IsNaN(other._value) ? 0 : -1;
-                }
-                else
-                {
-                    return 1;
-                }
+                return CompareTo(other);
             }
             else if (obj is null)
             {