Ryujinx/ChocolArm64/Instruction/ASoftFloat.cs

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using ChocolArm64.State;
using System;
using System.Diagnostics;
using System.Runtime.CompilerServices;
namespace ChocolArm64.Instruction
{
static class ASoftFloat
{
static ASoftFloat()
{
RecipEstimateTable = BuildRecipEstimateTable();
InvSqrtEstimateTable = BuildInvSqrtEstimateTable();
}
private static readonly byte[] RecipEstimateTable;
private static readonly byte[] InvSqrtEstimateTable;
private static byte[] BuildRecipEstimateTable()
{
byte[] Table = new byte[256];
for (ulong index = 0; index < 256; index++)
{
ulong a = index | 0x100;
a = (a << 1) + 1;
ulong b = 0x80000 / a;
b = (b + 1) >> 1;
Table[index] = (byte)(b & 0xFF);
}
return Table;
}
private static byte[] BuildInvSqrtEstimateTable()
{
byte[] Table = new byte[512];
for (ulong index = 128; index < 512; index++)
{
ulong a = index;
if (a < 256)
{
a = (a << 1) + 1;
}
else
{
a = (a | 1) << 1;
}
ulong b = 256;
while (a * (b + 1) * (b + 1) < (1ul << 28))
{
b++;
}
b = (b + 1) >> 1;
Table[index] = (byte)(b & 0xFF);
}
return Table;
}
[MethodImpl(MethodImplOptions.AggressiveInlining)]
public static float RecipEstimate(float x)
{
return (float)RecipEstimate((double)x);
}
public static double RecipEstimate(double x)
{
ulong x_bits = (ulong)BitConverter.DoubleToInt64Bits(x);
ulong x_sign = x_bits & 0x8000000000000000;
ulong x_exp = (x_bits >> 52) & 0x7FF;
ulong scaled = x_bits & ((1ul << 52) - 1);
if (x_exp >= 2045)
{
if (x_exp == 0x7ff && scaled != 0)
{
// NaN
return BitConverter.Int64BitsToDouble((long)(x_bits | 0x0008000000000000));
}
// Infinity, or Out of range -> Zero
return BitConverter.Int64BitsToDouble((long)x_sign);
}
if (x_exp == 0)
{
if (scaled == 0)
{
// Zero -> Infinity
return BitConverter.Int64BitsToDouble((long)(x_sign | 0x7FF0000000000000));
}
// Denormal
if ((scaled & (1ul << 51)) == 0)
{
x_exp = ~0ul;
scaled <<= 2;
}
else
{
scaled <<= 1;
}
}
scaled >>= 44;
scaled &= 0xFF;
ulong result_exp = (2045 - x_exp) & 0x7FF;
ulong estimate = (ulong)RecipEstimateTable[scaled];
ulong fraction = estimate << 44;
if (result_exp == 0)
{
fraction >>= 1;
fraction |= 1ul << 51;
}
else if (result_exp == 0x7FF)
{
result_exp = 0;
fraction >>= 2;
fraction |= 1ul << 50;
}
ulong result = x_sign | (result_exp << 52) | fraction;
return BitConverter.Int64BitsToDouble((long)result);
}
[MethodImpl(MethodImplOptions.AggressiveInlining)]
public static float InvSqrtEstimate(float x)
{
return (float)InvSqrtEstimate((double)x);
}
public static double InvSqrtEstimate(double x)
{
ulong x_bits = (ulong)BitConverter.DoubleToInt64Bits(x);
ulong x_sign = x_bits & 0x8000000000000000;
long x_exp = (long)((x_bits >> 52) & 0x7FF);
ulong scaled = x_bits & ((1ul << 52) - 1);
if (x_exp == 0x7FF && scaled != 0)
{
// NaN
return BitConverter.Int64BitsToDouble((long)(x_bits | 0x0008000000000000));
}
if (x_exp == 0)
{
if (scaled == 0)
{
// Zero -> Infinity
return BitConverter.Int64BitsToDouble((long)(x_sign | 0x7FF0000000000000));
}
// Denormal
while ((scaled & (1 << 51)) == 0)
{
scaled <<= 1;
x_exp--;
}
scaled <<= 1;
}
if (x_sign != 0)
{
// Negative -> NaN
return BitConverter.Int64BitsToDouble((long)0x7FF8000000000000);
}
if (x_exp == 0x7ff && scaled == 0)
{
// Infinity -> Zero
return BitConverter.Int64BitsToDouble((long)x_sign);
}
if (((ulong)x_exp & 1) == 1)
{
scaled >>= 45;
scaled &= 0xFF;
scaled |= 0x80;
}
else
{
scaled >>= 44;
scaled &= 0xFF;
scaled |= 0x100;
}
ulong result_exp = ((ulong)(3068 - x_exp) / 2) & 0x7FF;
ulong estimate = (ulong)InvSqrtEstimateTable[scaled];
ulong fraction = estimate << 44;
ulong result = x_sign | (result_exp << 52) | fraction;
return BitConverter.Int64BitsToDouble((long)result);
}
}
static class ASoftFloat16_32
{
public static float FPConvert(ushort ValueBits, AThreadState State)
{
Debug.WriteLineIf(State.Fpcr != 0, $"ASoftFloat16_32.FPConvert: State.Fpcr = 0x{State.Fpcr:X8}");
double Real = ValueBits.FPUnpackCV(out FPType Type, out bool Sign, State);
float Result;
if (Type == FPType.SNaN || Type == FPType.QNaN)
{
if (State.GetFpcrFlag(FPCR.DN))
{
Result = FPDefaultNaN();
}
else
{
Result = FPConvertNaN(ValueBits);
}
if (Type == FPType.SNaN)
{
FPProcessException(FPExc.InvalidOp, State);
}
}
else if (Type == FPType.Infinity)
{
Result = FPInfinity(Sign);
}
else if (Type == FPType.Zero)
{
Result = FPZero(Sign);
}
else
{
Result = FPRoundCV(Real, State);
}
return Result;
}
private static float FPDefaultNaN()
{
return -float.NaN;
}
private static float FPInfinity(bool Sign)
{
return Sign ? float.NegativeInfinity : float.PositiveInfinity;
}
private static float FPZero(bool Sign)
{
return Sign ? -0f : +0f;
}
private static float FPMaxNormal(bool Sign)
{
return Sign ? float.MinValue : float.MaxValue;
}
private static double FPUnpackCV(this ushort ValueBits, out FPType Type, out bool Sign, AThreadState State)
{
Sign = (~(uint)ValueBits & 0x8000u) == 0u;
uint Exp16 = ((uint)ValueBits & 0x7C00u) >> 10;
uint Frac16 = (uint)ValueBits & 0x03FFu;
double Real;
if (Exp16 == 0u)
{
if (Frac16 == 0u)
{
Type = FPType.Zero;
Real = 0d;
}
else
{
Type = FPType.Nonzero; // Subnormal.
Real = Math.Pow(2d, -14) * ((double)Frac16 * Math.Pow(2d, -10));
}
}
else if (Exp16 == 0x1Fu && !State.GetFpcrFlag(FPCR.AHP))
{
if (Frac16 == 0u)
{
Type = FPType.Infinity;
Real = Math.Pow(2d, 1000);
}
else
{
Type = (~Frac16 & 0x0200u) == 0u ? FPType.QNaN : FPType.SNaN;
Real = 0d;
}
}
else
{
Type = FPType.Nonzero; // Normal.
Real = Math.Pow(2d, (int)Exp16 - 15) * (1d + (double)Frac16 * Math.Pow(2d, -10));
}
return Sign ? -Real : Real;
}
private static float FPRoundCV(double Real, AThreadState State)
{
const int MinimumExp = -126;
const int E = 8;
const int F = 23;
bool Sign;
double Mantissa;
if (Real < 0d)
{
Sign = true;
Mantissa = -Real;
}
else
{
Sign = false;
Mantissa = Real;
}
int Exponent = 0;
while (Mantissa < 1d)
{
Mantissa *= 2d;
Exponent--;
}
while (Mantissa >= 2d)
{
Mantissa /= 2d;
Exponent++;
}
if (State.GetFpcrFlag(FPCR.FZ) && Exponent < MinimumExp)
{
State.SetFpsrFlag(FPSR.UFC);
return FPZero(Sign);
}
uint BiasedExp = (uint)Math.Max(Exponent - MinimumExp + 1, 0);
if (BiasedExp == 0u)
{
Mantissa /= Math.Pow(2d, MinimumExp - Exponent);
}
uint IntMant = (uint)Math.Floor(Mantissa * Math.Pow(2d, F));
double Error = Mantissa * Math.Pow(2d, F) - (double)IntMant;
if (BiasedExp == 0u && (Error != 0d || State.GetFpcrFlag(FPCR.UFE)))
{
FPProcessException(FPExc.Underflow, State);
}
bool OverflowToInf;
bool RoundUp;
switch (State.FPRoundingMode())
{
default:
case ARoundMode.ToNearest:
RoundUp = (Error > 0.5d || (Error == 0.5d && (IntMant & 1u) == 1u));
OverflowToInf = true;
break;
case ARoundMode.TowardsPlusInfinity:
RoundUp = (Error != 0d && !Sign);
OverflowToInf = !Sign;
break;
case ARoundMode.TowardsMinusInfinity:
RoundUp = (Error != 0d && Sign);
OverflowToInf = Sign;
break;
case ARoundMode.TowardsZero:
RoundUp = false;
OverflowToInf = false;
break;
}
if (RoundUp)
{
IntMant++;
if (IntMant == (uint)Math.Pow(2d, F))
{
BiasedExp = 1u;
}
if (IntMant == (uint)Math.Pow(2d, F + 1))
{
BiasedExp++;
IntMant >>= 1;
}
}
float Result;
if (BiasedExp >= (uint)Math.Pow(2d, E) - 1u)
{
Result = OverflowToInf ? FPInfinity(Sign) : FPMaxNormal(Sign);
FPProcessException(FPExc.Overflow, State);
Error = 1d;
}
else
{
Result = BitConverter.Int32BitsToSingle(
(int)((Sign ? 1u : 0u) << 31 | (BiasedExp & 0xFFu) << 23 | (IntMant & 0x007FFFFFu)));
}
if (Error != 0d)
{
FPProcessException(FPExc.Inexact, State);
}
return Result;
}
private static float FPConvertNaN(ushort ValueBits)
{
return BitConverter.Int32BitsToSingle(
(int)(((uint)ValueBits & 0x8000u) << 16 | 0x7FC00000u | ((uint)ValueBits & 0x01FFu) << 13));
}
private static void FPProcessException(FPExc Exc, AThreadState State)
{
int Enable = (int)Exc + 8;
if ((State.Fpcr & (1 << Enable)) != 0)
{
throw new NotImplementedException("floating-point trap handling");
}
else
{
State.Fpsr |= 1 << (int)Exc;
}
}
}
static class ASoftFloat32_16
{
public static ushort FPConvert(float Value, AThreadState State)
{
Debug.WriteLineIf(State.Fpcr != 0, $"ASoftFloat32_16.FPConvert: State.Fpcr = 0x{State.Fpcr:X8}");
double Real = Value.FPUnpackCV(out FPType Type, out bool Sign, State, out uint ValueBits);
bool AltHp = State.GetFpcrFlag(FPCR.AHP);
ushort ResultBits;
if (Type == FPType.SNaN || Type == FPType.QNaN)
{
if (AltHp)
{
ResultBits = FPZero(Sign);
}
else if (State.GetFpcrFlag(FPCR.DN))
{
ResultBits = FPDefaultNaN();
}
else
{
ResultBits = FPConvertNaN(ValueBits);
}
if (Type == FPType.SNaN || AltHp)
{
FPProcessException(FPExc.InvalidOp, State);
}
}
else if (Type == FPType.Infinity)
{
if (AltHp)
{
ResultBits = (ushort)((Sign ? 1u : 0u) << 15 | 0x7FFFu);
FPProcessException(FPExc.InvalidOp, State);
}
else
{
ResultBits = FPInfinity(Sign);
}
}
else if (Type == FPType.Zero)
{
ResultBits = FPZero(Sign);
}
else
{
ResultBits = FPRoundCV(Real, State);
}
return ResultBits;
}
private static ushort FPDefaultNaN()
{
return (ushort)0x7E00u;
}
private static ushort FPInfinity(bool Sign)
{
return Sign ? (ushort)0xFC00u : (ushort)0x7C00u;
}
private static ushort FPZero(bool Sign)
{
return Sign ? (ushort)0x8000u : (ushort)0x0000u;
}
private static ushort FPMaxNormal(bool Sign)
{
return Sign ? (ushort)0xFBFFu : (ushort)0x7BFFu;
}
private static double FPUnpackCV(this float Value, out FPType Type, out bool Sign, AThreadState State, out uint ValueBits)
{
ValueBits = (uint)BitConverter.SingleToInt32Bits(Value);
Sign = (~ValueBits & 0x80000000u) == 0u;
uint Exp32 = (ValueBits & 0x7F800000u) >> 23;
uint Frac32 = ValueBits & 0x007FFFFFu;
double Real;
if (Exp32 == 0u)
{
if (Frac32 == 0u || State.GetFpcrFlag(FPCR.FZ))
{
Type = FPType.Zero;
Real = 0d;
if (Frac32 != 0u) FPProcessException(FPExc.InputDenorm, State);
}
else
{
Type = FPType.Nonzero; // Subnormal.
Real = Math.Pow(2d, -126) * ((double)Frac32 * Math.Pow(2d, -23));
}
}
else if (Exp32 == 0xFFu)
{
if (Frac32 == 0u)
{
Type = FPType.Infinity;
Real = Math.Pow(2d, 1000);
}
else
{
Type = (~Frac32 & 0x00400000u) == 0u ? FPType.QNaN : FPType.SNaN;
Real = 0d;
}
}
else
{
Type = FPType.Nonzero; // Normal.
Real = Math.Pow(2d, (int)Exp32 - 127) * (1d + (double)Frac32 * Math.Pow(2d, -23));
}
return Sign ? -Real : Real;
}
private static ushort FPRoundCV(double Real, AThreadState State)
{
const int MinimumExp = -14;
const int E = 5;
const int F = 10;
bool Sign;
double Mantissa;
if (Real < 0d)
{
Sign = true;
Mantissa = -Real;
}
else
{
Sign = false;
Mantissa = Real;
}
int Exponent = 0;
while (Mantissa < 1d)
{
Mantissa *= 2d;
Exponent--;
}
while (Mantissa >= 2d)
{
Mantissa /= 2d;
Exponent++;
}
uint BiasedExp = (uint)Math.Max(Exponent - MinimumExp + 1, 0);
if (BiasedExp == 0u)
{
Mantissa /= Math.Pow(2d, MinimumExp - Exponent);
}
uint IntMant = (uint)Math.Floor(Mantissa * Math.Pow(2d, F));
double Error = Mantissa * Math.Pow(2d, F) - (double)IntMant;
if (BiasedExp == 0u && (Error != 0d || State.GetFpcrFlag(FPCR.UFE)))
{
FPProcessException(FPExc.Underflow, State);
}
bool OverflowToInf;
bool RoundUp;
switch (State.FPRoundingMode())
{
default:
case ARoundMode.ToNearest:
RoundUp = (Error > 0.5d || (Error == 0.5d && (IntMant & 1u) == 1u));
OverflowToInf = true;
break;
case ARoundMode.TowardsPlusInfinity:
RoundUp = (Error != 0d && !Sign);
OverflowToInf = !Sign;
break;
case ARoundMode.TowardsMinusInfinity:
RoundUp = (Error != 0d && Sign);
OverflowToInf = Sign;
break;
case ARoundMode.TowardsZero:
RoundUp = false;
OverflowToInf = false;
break;
}
if (RoundUp)
{
IntMant++;
if (IntMant == (uint)Math.Pow(2d, F))
{
BiasedExp = 1u;
}
if (IntMant == (uint)Math.Pow(2d, F + 1))
{
BiasedExp++;
IntMant >>= 1;
}
}
ushort ResultBits;
if (!State.GetFpcrFlag(FPCR.AHP))
{
if (BiasedExp >= (uint)Math.Pow(2d, E) - 1u)
{
ResultBits = OverflowToInf ? FPInfinity(Sign) : FPMaxNormal(Sign);
FPProcessException(FPExc.Overflow, State);
Error = 1d;
}
else
{
ResultBits = (ushort)((Sign ? 1u : 0u) << 15 | (BiasedExp & 0x1Fu) << 10 | (IntMant & 0x03FFu));
}
}
else
{
if (BiasedExp >= (uint)Math.Pow(2d, E))
{
ResultBits = (ushort)((Sign ? 1u : 0u) << 15 | 0x7FFFu);
FPProcessException(FPExc.InvalidOp, State);
Error = 0d;
}
else
{
ResultBits = (ushort)((Sign ? 1u : 0u) << 15 | (BiasedExp & 0x1Fu) << 10 | (IntMant & 0x03FFu));
}
}
if (Error != 0d)
{
FPProcessException(FPExc.Inexact, State);
}
return ResultBits;
}
private static ushort FPConvertNaN(uint ValueBits)
{
return (ushort)((ValueBits & 0x80000000u) >> 16 | 0x7E00u | (ValueBits & 0x003FE000u) >> 13);
}
private static void FPProcessException(FPExc Exc, AThreadState State)
{
int Enable = (int)Exc + 8;
if ((State.Fpcr & (1 << Enable)) != 0)
{
throw new NotImplementedException("floating-point trap handling");
}
else
{
State.Fpsr |= 1 << (int)Exc;
}
}
}
static class ASoftFloat_32
{
public static float FPAdd(float Value1, float Value2, AThreadState State)
{
Debug.WriteLineIf(State.Fpcr != 0, $"ASoftFloat_32.FPAdd: State.Fpcr = 0x{State.Fpcr:X8}");
Value1 = Value1.FPUnpack(out FPType Type1, out bool Sign1, out uint Op1);
Value2 = Value2.FPUnpack(out FPType Type2, out bool Sign2, out uint Op2);
float Result = FPProcessNaNs(Type1, Type2, Op1, Op2, State, out bool Done);
if (!Done)
{
bool Inf1 = Type1 == FPType.Infinity; bool Zero1 = Type1 == FPType.Zero;
bool Inf2 = Type2 == FPType.Infinity; bool Zero2 = Type2 == FPType.Zero;
if (Inf1 && Inf2 && Sign1 == !Sign2)
{
Result = FPDefaultNaN();
FPProcessException(FPExc.InvalidOp, State);
}
else if ((Inf1 && !Sign1) || (Inf2 && !Sign2))
{
Result = FPInfinity(false);
}
else if ((Inf1 && Sign1) || (Inf2 && Sign2))
{
Result = FPInfinity(true);
}
else if (Zero1 && Zero2 && Sign1 == Sign2)
{
Result = FPZero(Sign1);
}
else
{
Result = Value1 + Value2;
}
}
return Result;
}
public static float FPDiv(float Value1, float Value2, AThreadState State)
{
Debug.WriteLineIf(State.Fpcr != 0, $"ASoftFloat_32.FPDiv: State.Fpcr = 0x{State.Fpcr:X8}");
Value1 = Value1.FPUnpack(out FPType Type1, out bool Sign1, out uint Op1);
Value2 = Value2.FPUnpack(out FPType Type2, out bool Sign2, out uint Op2);
float Result = FPProcessNaNs(Type1, Type2, Op1, Op2, State, out bool Done);
if (!Done)
{
bool Inf1 = Type1 == FPType.Infinity; bool Zero1 = Type1 == FPType.Zero;
bool Inf2 = Type2 == FPType.Infinity; bool Zero2 = Type2 == FPType.Zero;
if ((Inf1 && Inf2) || (Zero1 && Zero2))
{
Result = FPDefaultNaN();
FPProcessException(FPExc.InvalidOp, State);
}
else if (Inf1 || Zero2)
{
Result = FPInfinity(Sign1 ^ Sign2);
if (!Inf1) FPProcessException(FPExc.DivideByZero, State);
}
else if (Zero1 || Inf2)
{
Result = FPZero(Sign1 ^ Sign2);
}
else
{
Result = Value1 / Value2;
}
}
return Result;
}
public static float FPMax(float Value1, float Value2, AThreadState State)
{
Debug.WriteLineIf(State.Fpcr != 0, $"ASoftFloat_32.FPMax: State.Fpcr = 0x{State.Fpcr:X8}");
Value1 = Value1.FPUnpack(out FPType Type1, out bool Sign1, out uint Op1);
Value2 = Value2.FPUnpack(out FPType Type2, out bool Sign2, out uint Op2);
float Result = FPProcessNaNs(Type1, Type2, Op1, Op2, State, out bool Done);
if (!Done)
{
if (Value1 > Value2)
{
if (Type1 == FPType.Infinity)
{
Result = FPInfinity(Sign1);
}
else if (Type1 == FPType.Zero)
{
Result = FPZero(Sign1 && Sign2);
}
else
{
Result = Value1;
}
}
else
{
if (Type2 == FPType.Infinity)
{
Result = FPInfinity(Sign2);
}
else if (Type2 == FPType.Zero)
{
Result = FPZero(Sign1 && Sign2);
}
else
{
Result = Value2;
}
}
}
return Result;
}
public static float FPMaxNum(float Value1, float Value2, AThreadState State)
{
Debug.WriteIf(State.Fpcr != 0, "ASoftFloat_32.FPMaxNum: ");
Value1.FPUnpack(out FPType Type1, out _, out _);
Value2.FPUnpack(out FPType Type2, out _, out _);
if (Type1 == FPType.QNaN && Type2 != FPType.QNaN)
{
Value1 = FPInfinity(true);
}
else if (Type1 != FPType.QNaN && Type2 == FPType.QNaN)
{
Value2 = FPInfinity(true);
}
return FPMax(Value1, Value2, State);
}
public static float FPMin(float Value1, float Value2, AThreadState State)
{
Debug.WriteLineIf(State.Fpcr != 0, $"ASoftFloat_32.FPMin: State.Fpcr = 0x{State.Fpcr:X8}");
Value1 = Value1.FPUnpack(out FPType Type1, out bool Sign1, out uint Op1);
Value2 = Value2.FPUnpack(out FPType Type2, out bool Sign2, out uint Op2);
float Result = FPProcessNaNs(Type1, Type2, Op1, Op2, State, out bool Done);
if (!Done)
{
if (Value1 < Value2)
{
if (Type1 == FPType.Infinity)
{
Result = FPInfinity(Sign1);
}
else if (Type1 == FPType.Zero)
{
Result = FPZero(Sign1 || Sign2);
}
else
{
Result = Value1;
}
}
else
{
if (Type2 == FPType.Infinity)
{
Result = FPInfinity(Sign2);
}
else if (Type2 == FPType.Zero)
{
Result = FPZero(Sign1 || Sign2);
}
else
{
Result = Value2;
}
}
}
return Result;
}
public static float FPMinNum(float Value1, float Value2, AThreadState State)
{
Debug.WriteIf(State.Fpcr != 0, "ASoftFloat_32.FPMinNum: ");
Value1.FPUnpack(out FPType Type1, out _, out _);
Value2.FPUnpack(out FPType Type2, out _, out _);
if (Type1 == FPType.QNaN && Type2 != FPType.QNaN)
{
Value1 = FPInfinity(false);
}
else if (Type1 != FPType.QNaN && Type2 == FPType.QNaN)
{
Value2 = FPInfinity(false);
}
return FPMin(Value1, Value2, State);
}
public static float FPMul(float Value1, float Value2, AThreadState State)
{
Debug.WriteLineIf(State.Fpcr != 0, $"ASoftFloat_32.FPMul: State.Fpcr = 0x{State.Fpcr:X8}");
Value1 = Value1.FPUnpack(out FPType Type1, out bool Sign1, out uint Op1);
Value2 = Value2.FPUnpack(out FPType Type2, out bool Sign2, out uint Op2);
float Result = FPProcessNaNs(Type1, Type2, Op1, Op2, State, out bool Done);
if (!Done)
{
bool Inf1 = Type1 == FPType.Infinity; bool Zero1 = Type1 == FPType.Zero;
bool Inf2 = Type2 == FPType.Infinity; bool Zero2 = Type2 == FPType.Zero;
if ((Inf1 && Zero2) || (Zero1 && Inf2))
{
Result = FPDefaultNaN();
FPProcessException(FPExc.InvalidOp, State);
}
else if (Inf1 || Inf2)
{
Result = FPInfinity(Sign1 ^ Sign2);
}
else if (Zero1 || Zero2)
{
Result = FPZero(Sign1 ^ Sign2);
}
else
{
Result = Value1 * Value2;
}
}
return Result;
}
public static float FPMulAdd(float ValueA, float Value1, float Value2, AThreadState State)
{
Debug.WriteLineIf(State.Fpcr != 0, $"ASoftFloat_32.FPMulAdd: State.Fpcr = 0x{State.Fpcr:X8}");
ValueA = ValueA.FPUnpack(out FPType TypeA, out bool SignA, out uint Addend);
Value1 = Value1.FPUnpack(out FPType Type1, out bool Sign1, out uint Op1);
Value2 = Value2.FPUnpack(out FPType Type2, out bool Sign2, out uint Op2);
bool Inf1 = Type1 == FPType.Infinity; bool Zero1 = Type1 == FPType.Zero;
bool Inf2 = Type2 == FPType.Infinity; bool Zero2 = Type2 == FPType.Zero;
float Result = FPProcessNaNs3(TypeA, Type1, Type2, Addend, Op1, Op2, State, out bool Done);
if (TypeA == FPType.QNaN && ((Inf1 && Zero2) || (Zero1 && Inf2)))
{
Result = FPDefaultNaN();
FPProcessException(FPExc.InvalidOp, State);
}
if (!Done)
{
bool InfA = TypeA == FPType.Infinity; bool ZeroA = TypeA == FPType.Zero;
bool SignP = Sign1 ^ Sign2;
bool InfP = Inf1 || Inf2;
bool ZeroP = Zero1 || Zero2;
if ((Inf1 && Zero2) || (Zero1 && Inf2) || (InfA && InfP && SignA != SignP))
{
Result = FPDefaultNaN();
FPProcessException(FPExc.InvalidOp, State);
}
else if ((InfA && !SignA) || (InfP && !SignP))
{
Result = FPInfinity(false);
}
else if ((InfA && SignA) || (InfP && SignP))
{
Result = FPInfinity(true);
}
else if (ZeroA && ZeroP && SignA == SignP)
{
Result = FPZero(SignA);
}
else
{
// TODO: When available, use: T MathF.FusedMultiplyAdd(T, T, T);
// https://github.com/dotnet/corefx/issues/31903
Result = ValueA + (Value1 * Value2);
}
}
return Result;
}
[MethodImpl(MethodImplOptions.AggressiveInlining)]
public static float FPMulSub(float ValueA, float Value1, float Value2, AThreadState State)
{
Debug.WriteIf(State.Fpcr != 0, "ASoftFloat_32.FPMulSub: ");
Value1 = Value1.FPNeg();
return FPMulAdd(ValueA, Value1, Value2, State);
}
public static float FPMulX(float Value1, float Value2, AThreadState State)
{
Debug.WriteLineIf(State.Fpcr != 0, $"ASoftFloat_32.FPMulX: State.Fpcr = 0x{State.Fpcr:X8}");
Value1 = Value1.FPUnpack(out FPType Type1, out bool Sign1, out uint Op1);
Value2 = Value2.FPUnpack(out FPType Type2, out bool Sign2, out uint Op2);
float Result = FPProcessNaNs(Type1, Type2, Op1, Op2, State, out bool Done);
if (!Done)
{
bool Inf1 = Type1 == FPType.Infinity; bool Zero1 = Type1 == FPType.Zero;
bool Inf2 = Type2 == FPType.Infinity; bool Zero2 = Type2 == FPType.Zero;
if ((Inf1 && Zero2) || (Zero1 && Inf2))
{
Result = FPTwo(Sign1 ^ Sign2);
}
else if (Inf1 || Inf2)
{
Result = FPInfinity(Sign1 ^ Sign2);
}
else if (Zero1 || Zero2)
{
Result = FPZero(Sign1 ^ Sign2);
}
else
{
Result = Value1 * Value2;
}
}
return Result;
}
public static float FPRecipStepFused(float Value1, float Value2, AThreadState State)
{
Debug.WriteLineIf(State.Fpcr != 0, $"ASoftFloat_32.FPRecipStepFused: State.Fpcr = 0x{State.Fpcr:X8}");
Value1 = Value1.FPNeg();
Value1 = Value1.FPUnpack(out FPType Type1, out bool Sign1, out uint Op1);
Value2 = Value2.FPUnpack(out FPType Type2, out bool Sign2, out uint Op2);
float Result = FPProcessNaNs(Type1, Type2, Op1, Op2, State, out bool Done);
if (!Done)
{
bool Inf1 = Type1 == FPType.Infinity; bool Zero1 = Type1 == FPType.Zero;
bool Inf2 = Type2 == FPType.Infinity; bool Zero2 = Type2 == FPType.Zero;
if ((Inf1 && Zero2) || (Zero1 && Inf2))
{
Result = FPTwo(false);
}
else if (Inf1 || Inf2)
{
Result = FPInfinity(Sign1 ^ Sign2);
}
else
{
// TODO: When available, use: T MathF.FusedMultiplyAdd(T, T, T);
// https://github.com/dotnet/corefx/issues/31903
Result = 2f + (Value1 * Value2);
}
}
return Result;
}
public static float FPRecpX(float Value, AThreadState State)
{
Debug.WriteLineIf(State.Fpcr != 0, $"ASoftFloat_32.FPRecpX: State.Fpcr = 0x{State.Fpcr:X8}");
Value.FPUnpack(out FPType Type, out bool Sign, out uint Op);
float Result;
if (Type == FPType.SNaN || Type == FPType.QNaN)
{
Result = FPProcessNaN(Type, Op, State);
}
else
{
uint NotExp = (~Op >> 23) & 0xFFu;
uint MaxExp = 0xFEu;
Result = BitConverter.Int32BitsToSingle(
(int)((Sign ? 1u : 0u) << 31 | (NotExp == 0xFFu ? MaxExp : NotExp) << 23));
}
return Result;
}
public static float FPRSqrtStepFused(float Value1, float Value2, AThreadState State)
{
Debug.WriteLineIf(State.Fpcr != 0, $"ASoftFloat_32.FPRSqrtStepFused: State.Fpcr = 0x{State.Fpcr:X8}");
Value1 = Value1.FPNeg();
Value1 = Value1.FPUnpack(out FPType Type1, out bool Sign1, out uint Op1);
Value2 = Value2.FPUnpack(out FPType Type2, out bool Sign2, out uint Op2);
float Result = FPProcessNaNs(Type1, Type2, Op1, Op2, State, out bool Done);
if (!Done)
{
bool Inf1 = Type1 == FPType.Infinity; bool Zero1 = Type1 == FPType.Zero;
bool Inf2 = Type2 == FPType.Infinity; bool Zero2 = Type2 == FPType.Zero;
if ((Inf1 && Zero2) || (Zero1 && Inf2))
{
Result = FPOnePointFive(false);
}
else if (Inf1 || Inf2)
{
Result = FPInfinity(Sign1 ^ Sign2);
}
else
{
// TODO: When available, use: T MathF.FusedMultiplyAdd(T, T, T);
// https://github.com/dotnet/corefx/issues/31903
Result = (3f + (Value1 * Value2)) / 2f;
}
}
return Result;
}
public static float FPSqrt(float Value, AThreadState State)
{
Debug.WriteLineIf(State.Fpcr != 0, $"ASoftFloat_32.FPSqrt: State.Fpcr = 0x{State.Fpcr:X8}");
Value = Value.FPUnpack(out FPType Type, out bool Sign, out uint Op);
float Result;
if (Type == FPType.SNaN || Type == FPType.QNaN)
{
Result = FPProcessNaN(Type, Op, State);
}
else if (Type == FPType.Zero)
{
Result = FPZero(Sign);
}
else if (Type == FPType.Infinity && !Sign)
{
Result = FPInfinity(Sign);
}
else if (Sign)
{
Result = FPDefaultNaN();
FPProcessException(FPExc.InvalidOp, State);
}
else
{
Result = MathF.Sqrt(Value);
}
return Result;
}
public static float FPSub(float Value1, float Value2, AThreadState State)
{
Debug.WriteLineIf(State.Fpcr != 0, $"ASoftFloat_32.FPSub: State.Fpcr = 0x{State.Fpcr:X8}");
Value1 = Value1.FPUnpack(out FPType Type1, out bool Sign1, out uint Op1);
Value2 = Value2.FPUnpack(out FPType Type2, out bool Sign2, out uint Op2);
float Result = FPProcessNaNs(Type1, Type2, Op1, Op2, State, out bool Done);
if (!Done)
{
bool Inf1 = Type1 == FPType.Infinity; bool Zero1 = Type1 == FPType.Zero;
bool Inf2 = Type2 == FPType.Infinity; bool Zero2 = Type2 == FPType.Zero;
if (Inf1 && Inf2 && Sign1 == Sign2)
{
Result = FPDefaultNaN();
FPProcessException(FPExc.InvalidOp, State);
}
else if ((Inf1 && !Sign1) || (Inf2 && Sign2))
{
Result = FPInfinity(false);
}
else if ((Inf1 && Sign1) || (Inf2 && !Sign2))
{
Result = FPInfinity(true);
}
else if (Zero1 && Zero2 && Sign1 == !Sign2)
{
Result = FPZero(Sign1);
}
else
{
Result = Value1 - Value2;
}
}
return Result;
}
private static float FPDefaultNaN()
{
return -float.NaN;
}
private static float FPInfinity(bool Sign)
{
return Sign ? float.NegativeInfinity : float.PositiveInfinity;
}
private static float FPZero(bool Sign)
{
return Sign ? -0f : +0f;
}
private static float FPTwo(bool Sign)
{
return Sign ? -2f : +2f;
}
private static float FPOnePointFive(bool Sign)
{
return Sign ? -1.5f : +1.5f;
}
private static float FPNeg(this float Value)
{
return -Value;
}
private static float FPUnpack(this float Value, out FPType Type, out bool Sign, out uint ValueBits)
{
ValueBits = (uint)BitConverter.SingleToInt32Bits(Value);
Sign = (~ValueBits & 0x80000000u) == 0u;
if ((ValueBits & 0x7F800000u) == 0u)
{
if ((ValueBits & 0x007FFFFFu) == 0u)
{
Type = FPType.Zero;
}
else
{
Type = FPType.Nonzero;
}
}
else if ((~ValueBits & 0x7F800000u) == 0u)
{
if ((ValueBits & 0x007FFFFFu) == 0u)
{
Type = FPType.Infinity;
}
else
{
Type = (~ValueBits & 0x00400000u) == 0u
? FPType.QNaN
: FPType.SNaN;
return FPZero(Sign);
}
}
else
{
Type = FPType.Nonzero;
}
return Value;
}
private static float FPProcessNaNs(
FPType Type1,
FPType Type2,
uint Op1,
uint Op2,
AThreadState State,
out bool Done)
{
Done = true;
if (Type1 == FPType.SNaN)
{
return FPProcessNaN(Type1, Op1, State);
}
else if (Type2 == FPType.SNaN)
{
return FPProcessNaN(Type2, Op2, State);
}
else if (Type1 == FPType.QNaN)
{
return FPProcessNaN(Type1, Op1, State);
}
else if (Type2 == FPType.QNaN)
{
return FPProcessNaN(Type2, Op2, State);
}
Done = false;
return FPZero(false);
}
private static float FPProcessNaNs3(
FPType Type1,
FPType Type2,
FPType Type3,
uint Op1,
uint Op2,
uint Op3,
AThreadState State,
out bool Done)
{
Done = true;
if (Type1 == FPType.SNaN)
{
return FPProcessNaN(Type1, Op1, State);
}
else if (Type2 == FPType.SNaN)
{
return FPProcessNaN(Type2, Op2, State);
}
else if (Type3 == FPType.SNaN)
{
return FPProcessNaN(Type3, Op3, State);
}
else if (Type1 == FPType.QNaN)
{
return FPProcessNaN(Type1, Op1, State);
}
else if (Type2 == FPType.QNaN)
{
return FPProcessNaN(Type2, Op2, State);
}
else if (Type3 == FPType.QNaN)
{
return FPProcessNaN(Type3, Op3, State);
}
Done = false;
return FPZero(false);
}
private static float FPProcessNaN(FPType Type, uint Op, AThreadState State)
{
if (Type == FPType.SNaN)
{
Op |= 1u << 22;
FPProcessException(FPExc.InvalidOp, State);
}
if (State.GetFpcrFlag(FPCR.DN))
{
return FPDefaultNaN();
}
return BitConverter.Int32BitsToSingle((int)Op);
}
private static void FPProcessException(FPExc Exc, AThreadState State)
{
int Enable = (int)Exc + 8;
if ((State.Fpcr & (1 << Enable)) != 0)
{
throw new NotImplementedException("floating-point trap handling");
}
else
{
State.Fpsr |= 1 << (int)Exc;
}
}
}
static class ASoftFloat_64
{
public static double FPAdd(double Value1, double Value2, AThreadState State)
{
Debug.WriteLineIf(State.Fpcr != 0, $"ASoftFloat_64.FPAdd: State.Fpcr = 0x{State.Fpcr:X8}");
Value1 = Value1.FPUnpack(out FPType Type1, out bool Sign1, out ulong Op1);
Value2 = Value2.FPUnpack(out FPType Type2, out bool Sign2, out ulong Op2);
double Result = FPProcessNaNs(Type1, Type2, Op1, Op2, State, out bool Done);
if (!Done)
{
bool Inf1 = Type1 == FPType.Infinity; bool Zero1 = Type1 == FPType.Zero;
bool Inf2 = Type2 == FPType.Infinity; bool Zero2 = Type2 == FPType.Zero;
if (Inf1 && Inf2 && Sign1 == !Sign2)
{
Result = FPDefaultNaN();
FPProcessException(FPExc.InvalidOp, State);
}
else if ((Inf1 && !Sign1) || (Inf2 && !Sign2))
{
Result = FPInfinity(false);
}
else if ((Inf1 && Sign1) || (Inf2 && Sign2))
{
Result = FPInfinity(true);
}
else if (Zero1 && Zero2 && Sign1 == Sign2)
{
Result = FPZero(Sign1);
}
else
{
Result = Value1 + Value2;
}
}
return Result;
}
public static double FPDiv(double Value1, double Value2, AThreadState State)
{
Debug.WriteLineIf(State.Fpcr != 0, $"ASoftFloat_64.FPDiv: State.Fpcr = 0x{State.Fpcr:X8}");
Value1 = Value1.FPUnpack(out FPType Type1, out bool Sign1, out ulong Op1);
Value2 = Value2.FPUnpack(out FPType Type2, out bool Sign2, out ulong Op2);
double Result = FPProcessNaNs(Type1, Type2, Op1, Op2, State, out bool Done);
if (!Done)
{
bool Inf1 = Type1 == FPType.Infinity; bool Zero1 = Type1 == FPType.Zero;
bool Inf2 = Type2 == FPType.Infinity; bool Zero2 = Type2 == FPType.Zero;
if ((Inf1 && Inf2) || (Zero1 && Zero2))
{
Result = FPDefaultNaN();
FPProcessException(FPExc.InvalidOp, State);
}
else if (Inf1 || Zero2)
{
Result = FPInfinity(Sign1 ^ Sign2);
if (!Inf1) FPProcessException(FPExc.DivideByZero, State);
}
else if (Zero1 || Inf2)
{
Result = FPZero(Sign1 ^ Sign2);
}
else
{
Result = Value1 / Value2;
}
}
return Result;
}
public static double FPMax(double Value1, double Value2, AThreadState State)
{
Debug.WriteLineIf(State.Fpcr != 0, $"ASoftFloat_64.FPMax: State.Fpcr = 0x{State.Fpcr:X8}");
Value1 = Value1.FPUnpack(out FPType Type1, out bool Sign1, out ulong Op1);
Value2 = Value2.FPUnpack(out FPType Type2, out bool Sign2, out ulong Op2);
double Result = FPProcessNaNs(Type1, Type2, Op1, Op2, State, out bool Done);
if (!Done)
{
if (Value1 > Value2)
{
if (Type1 == FPType.Infinity)
{
Result = FPInfinity(Sign1);
}
else if (Type1 == FPType.Zero)
{
Result = FPZero(Sign1 && Sign2);
}
else
{
Result = Value1;
}
}
else
{
if (Type2 == FPType.Infinity)
{
Result = FPInfinity(Sign2);
}
else if (Type2 == FPType.Zero)
{
Result = FPZero(Sign1 && Sign2);
}
else
{
Result = Value2;
}
}
}
return Result;
}
public static double FPMaxNum(double Value1, double Value2, AThreadState State)
{
Debug.WriteIf(State.Fpcr != 0, "ASoftFloat_64.FPMaxNum: ");
Value1.FPUnpack(out FPType Type1, out _, out _);
Value2.FPUnpack(out FPType Type2, out _, out _);
if (Type1 == FPType.QNaN && Type2 != FPType.QNaN)
{
Value1 = FPInfinity(true);
}
else if (Type1 != FPType.QNaN && Type2 == FPType.QNaN)
{
Value2 = FPInfinity(true);
}
return FPMax(Value1, Value2, State);
}
public static double FPMin(double Value1, double Value2, AThreadState State)
{
Debug.WriteLineIf(State.Fpcr != 0, $"ASoftFloat_64.FPMin: State.Fpcr = 0x{State.Fpcr:X8}");
Value1 = Value1.FPUnpack(out FPType Type1, out bool Sign1, out ulong Op1);
Value2 = Value2.FPUnpack(out FPType Type2, out bool Sign2, out ulong Op2);
double Result = FPProcessNaNs(Type1, Type2, Op1, Op2, State, out bool Done);
if (!Done)
{
if (Value1 < Value2)
{
if (Type1 == FPType.Infinity)
{
Result = FPInfinity(Sign1);
}
else if (Type1 == FPType.Zero)
{
Result = FPZero(Sign1 || Sign2);
}
else
{
Result = Value1;
}
}
else
{
if (Type2 == FPType.Infinity)
{
Result = FPInfinity(Sign2);
}
else if (Type2 == FPType.Zero)
{
Result = FPZero(Sign1 || Sign2);
}
else
{
Result = Value2;
}
}
}
return Result;
}
public static double FPMinNum(double Value1, double Value2, AThreadState State)
{
Debug.WriteIf(State.Fpcr != 0, "ASoftFloat_64.FPMinNum: ");
Value1.FPUnpack(out FPType Type1, out _, out _);
Value2.FPUnpack(out FPType Type2, out _, out _);
if (Type1 == FPType.QNaN && Type2 != FPType.QNaN)
{
Value1 = FPInfinity(false);
}
else if (Type1 != FPType.QNaN && Type2 == FPType.QNaN)
{
Value2 = FPInfinity(false);
}
return FPMin(Value1, Value2, State);
}
public static double FPMul(double Value1, double Value2, AThreadState State)
{
Debug.WriteLineIf(State.Fpcr != 0, $"ASoftFloat_64.FPMul: State.Fpcr = 0x{State.Fpcr:X8}");
Value1 = Value1.FPUnpack(out FPType Type1, out bool Sign1, out ulong Op1);
Value2 = Value2.FPUnpack(out FPType Type2, out bool Sign2, out ulong Op2);
double Result = FPProcessNaNs(Type1, Type2, Op1, Op2, State, out bool Done);
if (!Done)
{
bool Inf1 = Type1 == FPType.Infinity; bool Zero1 = Type1 == FPType.Zero;
bool Inf2 = Type2 == FPType.Infinity; bool Zero2 = Type2 == FPType.Zero;
if ((Inf1 && Zero2) || (Zero1 && Inf2))
{
Result = FPDefaultNaN();
FPProcessException(FPExc.InvalidOp, State);
}
else if (Inf1 || Inf2)
{
Result = FPInfinity(Sign1 ^ Sign2);
}
else if (Zero1 || Zero2)
{
Result = FPZero(Sign1 ^ Sign2);
}
else
{
Result = Value1 * Value2;
}
}
return Result;
}
public static double FPMulAdd(double ValueA, double Value1, double Value2, AThreadState State)
{
Debug.WriteLineIf(State.Fpcr != 0, $"ASoftFloat_64.FPMulAdd: State.Fpcr = 0x{State.Fpcr:X8}");
ValueA = ValueA.FPUnpack(out FPType TypeA, out bool SignA, out ulong Addend);
Value1 = Value1.FPUnpack(out FPType Type1, out bool Sign1, out ulong Op1);
Value2 = Value2.FPUnpack(out FPType Type2, out bool Sign2, out ulong Op2);
bool Inf1 = Type1 == FPType.Infinity; bool Zero1 = Type1 == FPType.Zero;
bool Inf2 = Type2 == FPType.Infinity; bool Zero2 = Type2 == FPType.Zero;
double Result = FPProcessNaNs3(TypeA, Type1, Type2, Addend, Op1, Op2, State, out bool Done);
if (TypeA == FPType.QNaN && ((Inf1 && Zero2) || (Zero1 && Inf2)))
{
Result = FPDefaultNaN();
FPProcessException(FPExc.InvalidOp, State);
}
if (!Done)
{
bool InfA = TypeA == FPType.Infinity; bool ZeroA = TypeA == FPType.Zero;
bool SignP = Sign1 ^ Sign2;
bool InfP = Inf1 || Inf2;
bool ZeroP = Zero1 || Zero2;
if ((Inf1 && Zero2) || (Zero1 && Inf2) || (InfA && InfP && SignA != SignP))
{
Result = FPDefaultNaN();
FPProcessException(FPExc.InvalidOp, State);
}
else if ((InfA && !SignA) || (InfP && !SignP))
{
Result = FPInfinity(false);
}
else if ((InfA && SignA) || (InfP && SignP))
{
Result = FPInfinity(true);
}
else if (ZeroA && ZeroP && SignA == SignP)
{
Result = FPZero(SignA);
}
else
{
// TODO: When available, use: T Math.FusedMultiplyAdd(T, T, T);
// https://github.com/dotnet/corefx/issues/31903
Result = ValueA + (Value1 * Value2);
}
}
return Result;
}
[MethodImpl(MethodImplOptions.AggressiveInlining)]
public static double FPMulSub(double ValueA, double Value1, double Value2, AThreadState State)
{
Debug.WriteIf(State.Fpcr != 0, "ASoftFloat_64.FPMulSub: ");
Value1 = Value1.FPNeg();
return FPMulAdd(ValueA, Value1, Value2, State);
}
public static double FPMulX(double Value1, double Value2, AThreadState State)
{
Debug.WriteLineIf(State.Fpcr != 0, $"ASoftFloat_64.FPMulX: State.Fpcr = 0x{State.Fpcr:X8}");
Value1 = Value1.FPUnpack(out FPType Type1, out bool Sign1, out ulong Op1);
Value2 = Value2.FPUnpack(out FPType Type2, out bool Sign2, out ulong Op2);
double Result = FPProcessNaNs(Type1, Type2, Op1, Op2, State, out bool Done);
if (!Done)
{
bool Inf1 = Type1 == FPType.Infinity; bool Zero1 = Type1 == FPType.Zero;
bool Inf2 = Type2 == FPType.Infinity; bool Zero2 = Type2 == FPType.Zero;
if ((Inf1 && Zero2) || (Zero1 && Inf2))
{
Result = FPTwo(Sign1 ^ Sign2);
}
else if (Inf1 || Inf2)
{
Result = FPInfinity(Sign1 ^ Sign2);
}
else if (Zero1 || Zero2)
{
Result = FPZero(Sign1 ^ Sign2);
}
else
{
Result = Value1 * Value2;
}
}
return Result;
}
public static double FPRecipStepFused(double Value1, double Value2, AThreadState State)
{
Debug.WriteLineIf(State.Fpcr != 0, $"ASoftFloat_64.FPRecipStepFused: State.Fpcr = 0x{State.Fpcr:X8}");
Value1 = Value1.FPNeg();
Value1 = Value1.FPUnpack(out FPType Type1, out bool Sign1, out ulong Op1);
Value2 = Value2.FPUnpack(out FPType Type2, out bool Sign2, out ulong Op2);
double Result = FPProcessNaNs(Type1, Type2, Op1, Op2, State, out bool Done);
if (!Done)
{
bool Inf1 = Type1 == FPType.Infinity; bool Zero1 = Type1 == FPType.Zero;
bool Inf2 = Type2 == FPType.Infinity; bool Zero2 = Type2 == FPType.Zero;
if ((Inf1 && Zero2) || (Zero1 && Inf2))
{
Result = FPTwo(false);
}
else if (Inf1 || Inf2)
{
Result = FPInfinity(Sign1 ^ Sign2);
}
else
{
// TODO: When available, use: T Math.FusedMultiplyAdd(T, T, T);
// https://github.com/dotnet/corefx/issues/31903
Result = 2d + (Value1 * Value2);
}
}
return Result;
}
public static double FPRecpX(double Value, AThreadState State)
{
Debug.WriteLineIf(State.Fpcr != 0, $"ASoftFloat_64.FPRecpX: State.Fpcr = 0x{State.Fpcr:X8}");
Value.FPUnpack(out FPType Type, out bool Sign, out ulong Op);
double Result;
if (Type == FPType.SNaN || Type == FPType.QNaN)
{
Result = FPProcessNaN(Type, Op, State);
}
else
{
ulong NotExp = (~Op >> 52) & 0x7FFul;
ulong MaxExp = 0x7FEul;
Result = BitConverter.Int64BitsToDouble(
(long)((Sign ? 1ul : 0ul) << 63 | (NotExp == 0x7FFul ? MaxExp : NotExp) << 52));
}
return Result;
}
public static double FPRSqrtStepFused(double Value1, double Value2, AThreadState State)
{
Debug.WriteLineIf(State.Fpcr != 0, $"ASoftFloat_64.FPRSqrtStepFused: State.Fpcr = 0x{State.Fpcr:X8}");
Value1 = Value1.FPNeg();
Value1 = Value1.FPUnpack(out FPType Type1, out bool Sign1, out ulong Op1);
Value2 = Value2.FPUnpack(out FPType Type2, out bool Sign2, out ulong Op2);
double Result = FPProcessNaNs(Type1, Type2, Op1, Op2, State, out bool Done);
if (!Done)
{
bool Inf1 = Type1 == FPType.Infinity; bool Zero1 = Type1 == FPType.Zero;
bool Inf2 = Type2 == FPType.Infinity; bool Zero2 = Type2 == FPType.Zero;
if ((Inf1 && Zero2) || (Zero1 && Inf2))
{
Result = FPOnePointFive(false);
}
else if (Inf1 || Inf2)
{
Result = FPInfinity(Sign1 ^ Sign2);
}
else
{
// TODO: When available, use: T Math.FusedMultiplyAdd(T, T, T);
// https://github.com/dotnet/corefx/issues/31903
Result = (3d + (Value1 * Value2)) / 2d;
}
}
return Result;
}
public static double FPSqrt(double Value, AThreadState State)
{
Debug.WriteLineIf(State.Fpcr != 0, $"ASoftFloat_64.FPSqrt: State.Fpcr = 0x{State.Fpcr:X8}");
Value = Value.FPUnpack(out FPType Type, out bool Sign, out ulong Op);
double Result;
if (Type == FPType.SNaN || Type == FPType.QNaN)
{
Result = FPProcessNaN(Type, Op, State);
}
else if (Type == FPType.Zero)
{
Result = FPZero(Sign);
}
else if (Type == FPType.Infinity && !Sign)
{
Result = FPInfinity(Sign);
}
else if (Sign)
{
Result = FPDefaultNaN();
FPProcessException(FPExc.InvalidOp, State);
}
else
{
Result = Math.Sqrt(Value);
}
return Result;
}
public static double FPSub(double Value1, double Value2, AThreadState State)
{
Debug.WriteLineIf(State.Fpcr != 0, $"ASoftFloat_64.FPSub: State.Fpcr = 0x{State.Fpcr:X8}");
Value1 = Value1.FPUnpack(out FPType Type1, out bool Sign1, out ulong Op1);
Value2 = Value2.FPUnpack(out FPType Type2, out bool Sign2, out ulong Op2);
double Result = FPProcessNaNs(Type1, Type2, Op1, Op2, State, out bool Done);
if (!Done)
{
bool Inf1 = Type1 == FPType.Infinity; bool Zero1 = Type1 == FPType.Zero;
bool Inf2 = Type2 == FPType.Infinity; bool Zero2 = Type2 == FPType.Zero;
if (Inf1 && Inf2 && Sign1 == Sign2)
{
Result = FPDefaultNaN();
FPProcessException(FPExc.InvalidOp, State);
}
else if ((Inf1 && !Sign1) || (Inf2 && Sign2))
{
Result = FPInfinity(false);
}
else if ((Inf1 && Sign1) || (Inf2 && !Sign2))
{
Result = FPInfinity(true);
}
else if (Zero1 && Zero2 && Sign1 == !Sign2)
{
Result = FPZero(Sign1);
}
else
{
Result = Value1 - Value2;
}
}
return Result;
}
private static double FPDefaultNaN()
{
return -double.NaN;
}
private static double FPInfinity(bool Sign)
{
return Sign ? double.NegativeInfinity : double.PositiveInfinity;
}
private static double FPZero(bool Sign)
{
return Sign ? -0d : +0d;
}
private static double FPTwo(bool Sign)
{
return Sign ? -2d : +2d;
}
private static double FPOnePointFive(bool Sign)
{
return Sign ? -1.5d : +1.5d;
}
private static double FPNeg(this double Value)
{
return -Value;
}
private static double FPUnpack(this double Value, out FPType Type, out bool Sign, out ulong ValueBits)
{
ValueBits = (ulong)BitConverter.DoubleToInt64Bits(Value);
Sign = (~ValueBits & 0x8000000000000000ul) == 0ul;
if ((ValueBits & 0x7FF0000000000000ul) == 0ul)
{
if ((ValueBits & 0x000FFFFFFFFFFFFFul) == 0ul)
{
Type = FPType.Zero;
}
else
{
Type = FPType.Nonzero;
}
}
else if ((~ValueBits & 0x7FF0000000000000ul) == 0ul)
{
if ((ValueBits & 0x000FFFFFFFFFFFFFul) == 0ul)
{
Type = FPType.Infinity;
}
else
{
Type = (~ValueBits & 0x0008000000000000ul) == 0ul
? FPType.QNaN
: FPType.SNaN;
return FPZero(Sign);
}
}
else
{
Type = FPType.Nonzero;
}
return Value;
}
private static double FPProcessNaNs(
FPType Type1,
FPType Type2,
ulong Op1,
ulong Op2,
AThreadState State,
out bool Done)
{
Done = true;
if (Type1 == FPType.SNaN)
{
return FPProcessNaN(Type1, Op1, State);
}
else if (Type2 == FPType.SNaN)
{
return FPProcessNaN(Type2, Op2, State);
}
else if (Type1 == FPType.QNaN)
{
return FPProcessNaN(Type1, Op1, State);
}
else if (Type2 == FPType.QNaN)
{
return FPProcessNaN(Type2, Op2, State);
}
Done = false;
return FPZero(false);
}
private static double FPProcessNaNs3(
FPType Type1,
FPType Type2,
FPType Type3,
ulong Op1,
ulong Op2,
ulong Op3,
AThreadState State,
out bool Done)
{
Done = true;
if (Type1 == FPType.SNaN)
{
return FPProcessNaN(Type1, Op1, State);
}
else if (Type2 == FPType.SNaN)
{
return FPProcessNaN(Type2, Op2, State);
}
else if (Type3 == FPType.SNaN)
{
return FPProcessNaN(Type3, Op3, State);
}
else if (Type1 == FPType.QNaN)
{
return FPProcessNaN(Type1, Op1, State);
}
else if (Type2 == FPType.QNaN)
{
return FPProcessNaN(Type2, Op2, State);
}
else if (Type3 == FPType.QNaN)
{
return FPProcessNaN(Type3, Op3, State);
}
Done = false;
return FPZero(false);
}
private static double FPProcessNaN(FPType Type, ulong Op, AThreadState State)
{
if (Type == FPType.SNaN)
{
Op |= 1ul << 51;
FPProcessException(FPExc.InvalidOp, State);
}
if (State.GetFpcrFlag(FPCR.DN))
{
return FPDefaultNaN();
}
return BitConverter.Int64BitsToDouble((long)Op);
}
private static void FPProcessException(FPExc Exc, AThreadState State)
{
int Enable = (int)Exc + 8;
if ((State.Fpcr & (1 << Enable)) != 0)
{
throw new NotImplementedException("floating-point trap handling");
}
else
{
State.Fpsr |= 1 << (int)Exc;
}
}
}
}