Add BFloat16

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

@@ -1,6 +1,7 @@
 // Licensed to the .NET Foundation under one or more agreements.
 // The .NET Foundation licenses this file to you under the MIT license.
 
+using System.Numerics;
 using System.Runtime.CompilerServices;
 using System.Runtime.InteropServices;
 using System.Runtime.Intrinsics;
@@ -934,6 +935,10 @@ public static bool ToBoolean(ReadOnlySpan<byte> value)
         [MethodImpl(MethodImplOptions.AggressiveInlining)]
         public static Half Int16BitsToHalf(short value) => new Half((ushort)(value));
 
+        internal static short BFloat16BitsToInt16(BFloat16 value) => (short)value._value;
+
+        internal static BFloat16 Int16BitsToBFloat16(short value) => new BFloat16((ushort)(value));
+
         /// <summary>
         /// Converts the specified double-precision floating point number to a 64-bit unsigned integer.
         /// </summary>
@@ -987,5 +992,9 @@ public static bool ToBoolean(ReadOnlySpan<byte> value)
         [CLSCompliant(false)]
         [MethodImpl(MethodImplOptions.AggressiveInlining)]
         public static Half UInt16BitsToHalf(ushort value) => new Half(value);
+
+        internal static ushort BFloat16BitsToUInt16(BFloat16 value) => value._value;
+
+        internal static BFloat16 UInt16BitsToBFloat16(ushort value) => new BFloat16(value);
     }
 }

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

@@ -1660,6 +1660,12 @@ static bool INumberBase<decimal>.TryConvertToChecked<TOther>(decimal value, [May
                 result = (TOther)(object)actualResult;
                 return true;
             }
+            else if (typeof(TOther) == typeof(BFloat16))
+            {
+                BFloat16 actualResult = checked((BFloat16)value);
+                result = (TOther)(object)actualResult;
+                return true;
+            }
             else if (typeof(TOther) == typeof(short))
             {
                 short actualResult = checked((short)value);
@@ -1748,6 +1754,12 @@ private static bool TryConvertTo<TOther>(decimal value, [MaybeNullWhen(false)] o
                 result = (TOther)(object)actualResult;
                 return true;
             }
+            else if (typeof(TOther) == typeof(BFloat16))
+            {
+                BFloat16 actualResult = (BFloat16)value;
+                result = (TOther)(object)actualResult;
+                return true;
+            }
             else if (typeof(TOther) == typeof(short))
             {
                 short actualResult = (value >= short.MaxValue) ? short.MaxValue :

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

@@ -1248,7 +1248,7 @@ private static bool TryConvertFrom<TOther>(TOther value, out double result)
                 result = (double)actualValue;
                 return true;
             }
-            if (typeof(TOther) == typeof(BFloat16))
+            else if (typeof(TOther) == typeof(BFloat16))
             {
                 BFloat16 actualValue = (BFloat16)(object)value;
                 result = (double)actualValue;

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

@@ -1015,7 +1015,7 @@ public static explicit operator double(Half value)
                 exp -= 1;
             }
 
-            return CreateDouble(sign, (ushort)(exp + 0x3F0), (ulong)sig << 42);
+            return Math.CreateDouble(sign, (ushort)(exp + 0x3F0), (ulong)sig << 42);
         }
 
         /// <summary>Explicitly converts a half-precision floating-point value to its nearest representable <see cref="float" /> value.</summary>
@@ -1177,10 +1177,6 @@ private static double CreateDoubleNaN(bool sign, ulong significand)
             return BitConverter.UInt64BitsToDouble(signInt | NaNBits | sigInt);
         }
 
-        private static float CreateSingle(bool sign, byte exp, uint sig) => BitConverter.UInt32BitsToSingle(((sign ? 1U : 0U) << float.SignShift) + ((uint)exp << float.BiasedExponentShift) + sig);
-
-        private static double CreateDouble(bool sign, ushort exp, ulong sig) => BitConverter.UInt64BitsToDouble(((sign ? 1UL : 0UL) << double.SignShift) + ((ulong)exp << double.BiasedExponentShift) + sig);
-
         #endregion
 
         //

src/libraries/System.Private.CoreLib/src/System/Int128.cs

@@ -1604,8 +1604,8 @@ private static bool TryConvertFromSaturating<TOther>(TOther value, out Int128 re
             else if (typeof(TOther) == typeof(BFloat16))
             {
                 BFloat16 actualValue = (BFloat16)(object)value;
-                result = (actualValue >= new BFloat16(0x7F00)) ? MaxValue :
-                         (actualValue <= new BFloat16(0xFF00)) ? MinValue : (Int128)actualValue;
+                result = (actualValue >= BitConverter.UInt16BitsToBFloat16(0x7F00)) ? MaxValue :
+                         (actualValue <= BitConverter.UInt16BitsToBFloat16(0xFF00)) ? MinValue : (Int128)actualValue;
                 return true;
             }
             else if (typeof(TOther) == typeof(short))
@@ -1686,8 +1686,8 @@ private static bool TryConvertFromTruncating<TOther>(TOther value, out Int128 re
             else if (typeof(TOther) == typeof(BFloat16))
             {
                 BFloat16 actualValue = (BFloat16)(object)value;
-                result = (actualValue >= new BFloat16(0x7F00)) ? MaxValue :
-                         (actualValue <= new BFloat16(0xFF00)) ? MinValue : (Int128)actualValue;
+                result = (actualValue >= BitConverter.UInt16BitsToBFloat16(0x7F00)) ? MaxValue :
+                         (actualValue <= BitConverter.UInt16BitsToBFloat16(0xFF00)) ? MinValue : (Int128)actualValue;
                 return true;
             }
             else if (typeof(TOther) == typeof(short))

src/libraries/System.Private.CoreLib/src/System/Int16.cs

@@ -981,8 +981,8 @@ private static bool TryConvertFromSaturating<TOther>(TOther value, out short res
             else if (typeof(TOther) == typeof(BFloat16))
             {
                 BFloat16 actualValue = (BFloat16)(object)value;
-                result = (actualValue >= new BFloat16(0x4700)) ? MaxValue :
-                         (actualValue <= new BFloat16(0xB700)) ? MinValue : (short)actualValue;
+                result = (actualValue >= BitConverter.UInt16BitsToBFloat16(0x4700)) ? MaxValue :
+                         (actualValue <= BitConverter.UInt16BitsToBFloat16(0xB700)) ? MinValue : (short)actualValue;
                 return true;
             }
             else if (typeof(TOther) == typeof(int))
@@ -1067,8 +1067,8 @@ private static bool TryConvertFromTruncating<TOther>(TOther value, out short res
             else if (typeof(TOther) == typeof(BFloat16))
             {
                 BFloat16 actualValue = (BFloat16)(object)value;
-                result = (actualValue >= new BFloat16(0x4700)) ? MaxValue :
-                         (actualValue <= new BFloat16(0xB700)) ? MinValue : (short)actualValue;
+                result = (actualValue >= BitConverter.UInt16BitsToBFloat16(0x4700)) ? MaxValue :
+                         (actualValue <= BitConverter.UInt16BitsToBFloat16(0xB700)) ? MinValue : (short)actualValue;
                 return true;
             }
             else if (typeof(TOther) == typeof(int))

src/libraries/System.Private.CoreLib/src/System/Int32.cs

@@ -1022,8 +1022,8 @@ private static bool TryConvertFromSaturating<TOther>(TOther value, out int resul
             else if (typeof(TOther) == typeof(BFloat16))
             {
                 BFloat16 actualValue = (BFloat16)(object)value;
-                result = (actualValue >= new BFloat16(0x4F00)) ? MaxValue :
-                         (actualValue <= new BFloat16(0xBF00)) ? MinValue : (int)actualValue;
+                result = (actualValue >= BitConverter.UInt16BitsToBFloat16(0x4F00)) ? MaxValue :
+                         (actualValue <= BitConverter.UInt16BitsToBFloat16(0xBF00)) ? MinValue : (int)actualValue;
                 return true;
             }
             else if (typeof(TOther) == typeof(short))
@@ -1107,8 +1107,8 @@ private static bool TryConvertFromTruncating<TOther>(TOther value, out int resul
             else if (typeof(TOther) == typeof(BFloat16))
             {
                 BFloat16 actualValue = (BFloat16)(object)value;
-                result = (actualValue >= new BFloat16(0x4F00)) ? MaxValue :
-                         (actualValue <= new BFloat16(0xBF00)) ? MinValue : (int)actualValue;
+                result = (actualValue >= BitConverter.UInt16BitsToBFloat16(0x4F00)) ? MaxValue :
+                         (actualValue <= BitConverter.UInt16BitsToBFloat16(0xBF00)) ? MinValue : (int)actualValue;
                 return true;
             }
             else if (typeof(TOther) == typeof(short))

src/libraries/System.Private.CoreLib/src/System/Int64.cs

@@ -1019,8 +1019,8 @@ private static bool TryConvertFromSaturating<TOther>(TOther value, out long resu
             else if (typeof(TOther) == typeof(BFloat16))
             {
                 BFloat16 actualValue = (BFloat16)(object)value;
-                result = (actualValue >= new BFloat16(0x5F00)) ? MaxValue :
-                         (actualValue <= new BFloat16(0xCF00)) ? MinValue : (long)actualValue;
+                result = (actualValue >= BitConverter.UInt16BitsToBFloat16(0x5F00)) ? MaxValue :
+                         (actualValue <= BitConverter.UInt16BitsToBFloat16(0xCF00)) ? MinValue : (long)actualValue;
                 return true;
             }
             else if (typeof(TOther) == typeof(short))
@@ -1102,8 +1102,8 @@ private static bool TryConvertFromTruncating<TOther>(TOther value, out long resu
             else if (typeof(TOther) == typeof(BFloat16))
             {
                 BFloat16 actualValue = (BFloat16)(object)value;
-                result = (actualValue >= new BFloat16(0x5F00)) ? MaxValue :
-                         (actualValue <= new BFloat16(0xCF00)) ? MinValue : (long)actualValue;
+                result = (actualValue >= BitConverter.UInt16BitsToBFloat16(0x5F00)) ? MaxValue :
+                         (actualValue <= BitConverter.UInt16BitsToBFloat16(0xCF00)) ? MinValue : (long)actualValue;
                 return true;
             }
             else if (typeof(TOther) == typeof(short))

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

@@ -1707,5 +1707,9 @@ internal static ulong ConvertToUInt64Checked(double value)
             ThrowHelper.ThrowOverflowException();
             return 0;
         }
+
+        internal static float CreateSingle(bool sign, byte exp, uint sig) => BitConverter.UInt32BitsToSingle(((sign ? 1U : 0U) << float.SignShift) + ((uint)exp << float.BiasedExponentShift) + sig);
+
+        internal static double CreateDouble(bool sign, ushort exp, ulong sig) => BitConverter.UInt64BitsToDouble(((sign ? 1UL : 0UL) << double.SignShift) + ((ulong)exp << double.BiasedExponentShift) + sig);
     }
 }