Rasagar/Library/PackageCache/com.unity.burst/Runtime/Intrinsics/x86/F16C.cs

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2024-08-26 13:07:20 -07:00
using System.Diagnostics;
namespace Unity.Burst.Intrinsics
{
public unsafe static partial class X86
{
/// <summary>
/// F16C intrinsics
/// </summary>
public static class F16C
{
/// <summary>
/// Evaluates to true at compile time if F16C intrinsics are supported.
///
/// Burst ties F16C support to AVX2 support to simplify feature sets to support.
/// </summary>
public static bool IsF16CSupported { get { return Avx2.IsAvx2Supported; } }
/// <summary>
/// Converts a half (hiding in a ushort) to a float (hiding in a uint).
/// </summary>
/// <param name="h">The half to convert</param>
/// <returns>The float result</returns>
[DebuggerStepThrough]
private static uint HalfToFloat(ushort h)
{
var signed = (h & 0x8000u) != 0;
var exponent = (h >> 10) & 0x1fu;
var mantissa = h & 0x3ffu;
var result = signed ? 0x80000000u : 0u;
if (!(exponent == 0 && mantissa == 0))
{
// Denormal (converts to normalized)
if (exponent == 0)
{
// Adjust mantissa so it's normalized (and keep track of exponent adjustment)
exponent = -1;
do
{
exponent++;
mantissa <<= 1;
} while ((mantissa & 0x400) == 0);
result |= (uint)((127 - 15 - exponent) << 23);
// Have to re-mask the mantissa here because we've been shifting bits up.
result |= (mantissa & 0x3ff) << 13;
}
else
{
var isInfOrNan = exponent == 0x1f;
result |= (uint)(isInfOrNan ? 255 : (127 - 15 + exponent) << 23);
result |= mantissa << 13;
}
}
return result;
}
/// <summary>
/// Convert packed half-precision (16-bit) floating-point elements in a to packed single-precision (32-bit) floating-point elements, and store the results in dst.
/// </summary>
/// <remarks>
/// **** vcvtph2ps xmm, xmm
/// </remarks>
/// <param name="a">Vector a</param>
/// <returns>Vector</returns>
[DebuggerStepThrough]
public static v128 cvtph_ps(v128 a)
{
return new v128(HalfToFloat(a.UShort0), HalfToFloat(a.UShort1), HalfToFloat(a.UShort2), HalfToFloat(a.UShort3));
}
/// <summary>
/// Convert packed half-precision (16-bit) floating-point elements in a to packed single-precision (32-bit) floating-point elements, and store the results in dst.
/// </summary>
/// <remarks>
/// **** vcvtph2ps ymm, xmm
/// </remarks>
/// <param name="a">Vector a</param>
/// <returns>Vector</returns>
[DebuggerStepThrough]
public static v256 mm256_cvtph_ps(v128 a)
{
return new v256(HalfToFloat(a.UShort0), HalfToFloat(a.UShort1), HalfToFloat(a.UShort2), HalfToFloat(a.UShort3), HalfToFloat(a.UShort4), HalfToFloat(a.UShort5), HalfToFloat(a.UShort6), HalfToFloat(a.UShort7));
}
// Using ftp://ftp.fox-toolkit.org/pub/fasthalffloatconversion.pdf
private static readonly ushort[] BaseTable =
{
0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000,
0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000,
0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000,
0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000,
0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000,
0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000,
0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0001, 0x0002, 0x0004, 0x0008, 0x0010, 0x0020, 0x0040, 0x0080, 0x0100,
0x0200, 0x0400, 0x0800, 0x0C00, 0x1000, 0x1400, 0x1800, 0x1C00, 0x2000, 0x2400, 0x2800, 0x2C00, 0x3000, 0x3400, 0x3800, 0x3C00,
0x4000, 0x4400, 0x4800, 0x4C00, 0x5000, 0x5400, 0x5800, 0x5C00, 0x6000, 0x6400, 0x6800, 0x6C00, 0x7000, 0x7400, 0x7800, 0x7C00,
0x7C00, 0x7C00, 0x7C00, 0x7C00, 0x7C00, 0x7C00, 0x7C00, 0x7C00, 0x7C00, 0x7C00, 0x7C00, 0x7C00, 0x7C00, 0x7C00, 0x7C00, 0x7C00,
0x7C00, 0x7C00, 0x7C00, 0x7C00, 0x7C00, 0x7C00, 0x7C00, 0x7C00, 0x7C00, 0x7C00, 0x7C00, 0x7C00, 0x7C00, 0x7C00, 0x7C00, 0x7C00,
0x7C00, 0x7C00, 0x7C00, 0x7C00, 0x7C00, 0x7C00, 0x7C00, 0x7C00, 0x7C00, 0x7C00, 0x7C00, 0x7C00, 0x7C00, 0x7C00, 0x7C00, 0x7C00,
0x7C00, 0x7C00, 0x7C00, 0x7C00, 0x7C00, 0x7C00, 0x7C00, 0x7C00, 0x7C00, 0x7C00, 0x7C00, 0x7C00, 0x7C00, 0x7C00, 0x7C00, 0x7C00,
0x7C00, 0x7C00, 0x7C00, 0x7C00, 0x7C00, 0x7C00, 0x7C00, 0x7C00, 0x7C00, 0x7C00, 0x7C00, 0x7C00, 0x7C00, 0x7C00, 0x7C00, 0x7C00,
0x7C00, 0x7C00, 0x7C00, 0x7C00, 0x7C00, 0x7C00, 0x7C00, 0x7C00, 0x7C00, 0x7C00, 0x7C00, 0x7C00, 0x7C00, 0x7C00, 0x7C00, 0x7C00,
0x7C00, 0x7C00, 0x7C00, 0x7C00, 0x7C00, 0x7C00, 0x7C00, 0x7C00, 0x7C00, 0x7C00, 0x7C00, 0x7C00, 0x7C00, 0x7C00, 0x7C00, 0x7C00,
0x8000, 0x8000, 0x8000, 0x8000, 0x8000, 0x8000, 0x8000, 0x8000, 0x8000, 0x8000, 0x8000, 0x8000, 0x8000, 0x8000, 0x8000, 0x8000,
0x8000, 0x8000, 0x8000, 0x8000, 0x8000, 0x8000, 0x8000, 0x8000, 0x8000, 0x8000, 0x8000, 0x8000, 0x8000, 0x8000, 0x8000, 0x8000,
0x8000, 0x8000, 0x8000, 0x8000, 0x8000, 0x8000, 0x8000, 0x8000, 0x8000, 0x8000, 0x8000, 0x8000, 0x8000, 0x8000, 0x8000, 0x8000,
0x8000, 0x8000, 0x8000, 0x8000, 0x8000, 0x8000, 0x8000, 0x8000, 0x8000, 0x8000, 0x8000, 0x8000, 0x8000, 0x8000, 0x8000, 0x8000,
0x8000, 0x8000, 0x8000, 0x8000, 0x8000, 0x8000, 0x8000, 0x8000, 0x8000, 0x8000, 0x8000, 0x8000, 0x8000, 0x8000, 0x8000, 0x8000,
0x8000, 0x8000, 0x8000, 0x8000, 0x8000, 0x8000, 0x8000, 0x8000, 0x8000, 0x8000, 0x8000, 0x8000, 0x8000, 0x8000, 0x8000, 0x8000,
0x8000, 0x8000, 0x8000, 0x8000, 0x8000, 0x8000, 0x8000, 0x8001, 0x8002, 0x8004, 0x8008, 0x8010, 0x8020, 0x8040, 0x8080, 0x8100,
0x8200, 0x8400, 0x8800, 0x8C00, 0x9000, 0x9400, 0x9800, 0x9C00, 0xA000, 0xA400, 0xA800, 0xAC00, 0xB000, 0xB400, 0xB800, 0xBC00,
0xC000, 0xC400, 0xC800, 0xCC00, 0xD000, 0xD400, 0xD800, 0xDC00, 0xE000, 0xE400, 0xE800, 0xEC00, 0xF000, 0xF400, 0xF800, 0xFC00,
0xFC00, 0xFC00, 0xFC00, 0xFC00, 0xFC00, 0xFC00, 0xFC00, 0xFC00, 0xFC00, 0xFC00, 0xFC00, 0xFC00, 0xFC00, 0xFC00, 0xFC00, 0xFC00,
0xFC00, 0xFC00, 0xFC00, 0xFC00, 0xFC00, 0xFC00, 0xFC00, 0xFC00, 0xFC00, 0xFC00, 0xFC00, 0xFC00, 0xFC00, 0xFC00, 0xFC00, 0xFC00,
0xFC00, 0xFC00, 0xFC00, 0xFC00, 0xFC00, 0xFC00, 0xFC00, 0xFC00, 0xFC00, 0xFC00, 0xFC00, 0xFC00, 0xFC00, 0xFC00, 0xFC00, 0xFC00,
0xFC00, 0xFC00, 0xFC00, 0xFC00, 0xFC00, 0xFC00, 0xFC00, 0xFC00, 0xFC00, 0xFC00, 0xFC00, 0xFC00, 0xFC00, 0xFC00, 0xFC00, 0xFC00,
0xFC00, 0xFC00, 0xFC00, 0xFC00, 0xFC00, 0xFC00, 0xFC00, 0xFC00, 0xFC00, 0xFC00, 0xFC00, 0xFC00, 0xFC00, 0xFC00, 0xFC00, 0xFC00,
0xFC00, 0xFC00, 0xFC00, 0xFC00, 0xFC00, 0xFC00, 0xFC00, 0xFC00, 0xFC00, 0xFC00, 0xFC00, 0xFC00, 0xFC00, 0xFC00, 0xFC00, 0xFC00,
0xFC00, 0xFC00, 0xFC00, 0xFC00, 0xFC00, 0xFC00, 0xFC00, 0xFC00, 0xFC00, 0xFC00, 0xFC00, 0xFC00, 0xFC00, 0xFC00, 0xFC00, 0xFC00,
};
private static readonly sbyte[] ShiftTable =
{
24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24,
24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24,
24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24,
24, 24, 24, 24, 24, 24, 24, 23, 22, 21, 20, 19, 18, 17, 16, 15, 14, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13,
13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24,
24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24,
24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24,
24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 13,
24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24,
24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24,
24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24,
24, 24, 24, 24, 24, 24, 24, 23, 22, 21, 20, 19, 18, 17, 16, 15, 14, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13,
13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24,
24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24,
24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24,
24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 13,
};
/// <summary>
/// Converts a float (hiding in a uint) to a half (hiding in a ushort).
/// </summary>
/// <param name="f">The float to convert</param>
/// <param name="rounding">Rounding mode</param>
/// <returns>The half result</returns>
[DebuggerStepThrough]
private static ushort FloatToHalf(uint f, int rounding)
{
var exponentAndSign = f >> 23;
var shift = ShiftTable[exponentAndSign];
var result = (uint)(BaseTable[exponentAndSign] + (ushort)((f & 0x7FFFFFu) >> shift));
// Check if the result is not Inf or NaN.
var isFinite = (result & 0x7C00) != 0x7C00;
var isNegative = (result & 0x8000) != 0;
if (rounding == (int)RoundingMode.FROUND_NINT_NOEXC)
{
var fWithRoundingBitPreserved = (f & 0x7FFFFFu) >> (shift - 1);
if ((exponentAndSign & 0xFF) == 102)
{
result++;
}
if (isFinite && ((fWithRoundingBitPreserved & 0x1u) != 0))
{
result++;
}
}
else if (rounding == (int)RoundingMode.FROUND_TRUNC_NOEXC)
{
if (!isFinite)
{
result -= (uint)(~shift & 0x1);
}
}
else if (rounding == (int)RoundingMode.FROUND_CEIL_NOEXC)
{
if (isFinite && !isNegative)
{
if ((exponentAndSign <= 102) && (exponentAndSign != 0))
{
result++;
}
else if ((f & 0x7FFFFFu & ((1u << shift) - 1u)) != 0)
{
result++;
}
}
var resultIsNegativeInf = (result == 0xFC00);
var inputIsNotNegativeInfOrNan = (exponentAndSign != 0x1FF);
if (resultIsNegativeInf && inputIsNotNegativeInfOrNan)
{
result--;
}
}
else if (rounding == (int)RoundingMode.FROUND_FLOOR_NOEXC)
{
if (isFinite && isNegative)
{
if ((exponentAndSign <= 358) && (exponentAndSign != 256))
{
result++;
}
else if ((f & 0x7FFFFFu & ((1u << shift) - 1u)) != 0)
{
result++;
}
}
var resultIsPositiveInf = (result == 0x7C00);
var inputIsNotPositiveInfOrNan = (exponentAndSign != 0xFF);
if (resultIsPositiveInf && inputIsNotPositiveInfOrNan)
{
result--;
}
}
return (ushort)result;
}
/// <summary>
/// Convert packed single-precision (32-bit) floating-point elements in a to packed half-precision (16-bit) floating-point elements, and store the results in dst.
///
/// Rounding is done according to the rounding parameter, which can be one of:
/// </summary>
/// <remarks>
/// **** cvtps2ph xmm, xmm, imm
/// </remarks>
/// <param name="a">Vector a</param>
/// <param name="rounding">Rounding mode</param>
/// <returns>Vector</returns>
[DebuggerStepThrough]
public static v128 cvtps_ph(v128 a, int rounding)
{
if (rounding == (int)RoundingMode.FROUND_RINT_NOEXC)
{
switch (MXCSR & MXCSRBits.RoundingControlMask)
{
case MXCSRBits.RoundToNearest:
rounding = (int)RoundingMode.FROUND_NINT_NOEXC;
break;
case MXCSRBits.RoundDown:
rounding = (int)RoundingMode.FROUND_FLOOR_NOEXC;
break;
case MXCSRBits.RoundUp:
rounding = (int)RoundingMode.FROUND_CEIL_NOEXC;
break;
case MXCSRBits.RoundTowardZero:
rounding = (int)RoundingMode.FROUND_TRUNC_NOEXC;
break;
}
}
return new v128(FloatToHalf(a.UInt0, rounding), FloatToHalf(a.UInt1, rounding), FloatToHalf(a.UInt2, rounding), FloatToHalf(a.UInt3, rounding), 0, 0, 0, 0);
}
/// <summary>
/// Convert packed single-precision (32-bit) floating-point elements in a to packed half-precision (16-bit) floating-point elements, and store the results in dst.
///
/// Rounding is done according to the rounding parameter, which can be one of:
/// </summary>
/// <remarks>
/// **** cvtps2ph xmm, ymm, imm
/// </remarks>
/// <param name="a">Vector a</param>
/// <param name="rounding">Rounding mode</param>
/// <returns>Vector</returns>
[DebuggerStepThrough]
public static v128 mm256_cvtps_ph(v256 a, int rounding)
{
if (rounding == (int)RoundingMode.FROUND_RINT_NOEXC)
{
switch (MXCSR & MXCSRBits.RoundingControlMask)
{
case MXCSRBits.RoundToNearest:
rounding = (int)RoundingMode.FROUND_NINT_NOEXC;
break;
case MXCSRBits.RoundDown:
rounding = (int)RoundingMode.FROUND_FLOOR_NOEXC;
break;
case MXCSRBits.RoundUp:
rounding = (int)RoundingMode.FROUND_CEIL_NOEXC;
break;
case MXCSRBits.RoundTowardZero:
rounding = (int)RoundingMode.FROUND_TRUNC_NOEXC;
break;
}
}
return new v128(FloatToHalf(a.UInt0, rounding), FloatToHalf(a.UInt1, rounding), FloatToHalf(a.UInt2, rounding), FloatToHalf(a.UInt3, rounding), FloatToHalf(a.UInt4, rounding), FloatToHalf(a.UInt5, rounding), FloatToHalf(a.UInt6, rounding), FloatToHalf(a.UInt7, rounding));
}
}
}
}