2128 lines
65 KiB
C#
2128 lines
65 KiB
C#
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using ChocolArm64.State;
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using System;
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using System.Diagnostics;
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using System.Runtime.CompilerServices;
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namespace ChocolArm64.Instructions
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{
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static class SoftFloat
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{
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static SoftFloat()
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{
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RecipEstimateTable = BuildRecipEstimateTable();
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InvSqrtEstimateTable = BuildInvSqrtEstimateTable();
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}
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private static readonly byte[] RecipEstimateTable;
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private static readonly byte[] InvSqrtEstimateTable;
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private static byte[] BuildRecipEstimateTable()
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{
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byte[] table = new byte[256];
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for (ulong index = 0; index < 256; index++)
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{
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ulong a = index | 0x100;
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a = (a << 1) + 1;
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ulong b = 0x80000 / a;
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b = (b + 1) >> 1;
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table[index] = (byte)(b & 0xFF);
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}
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return table;
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}
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private static byte[] BuildInvSqrtEstimateTable()
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{
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byte[] table = new byte[512];
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for (ulong index = 128; index < 512; index++)
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{
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ulong a = index;
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if (a < 256)
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{
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a = (a << 1) + 1;
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}
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else
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{
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a = (a | 1) << 1;
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}
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ulong b = 256;
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while (a * (b + 1) * (b + 1) < (1ul << 28))
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{
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b++;
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}
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b = (b + 1) >> 1;
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table[index] = (byte)(b & 0xFF);
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}
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return table;
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}
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[MethodImpl(MethodImplOptions.AggressiveInlining)]
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public static float RecipEstimate(float x)
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{
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return (float)RecipEstimate((double)x);
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}
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public static double RecipEstimate(double x)
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{
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ulong xBits = (ulong)BitConverter.DoubleToInt64Bits(x);
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ulong xSign = xBits & 0x8000000000000000;
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ulong xExp = (xBits >> 52) & 0x7FF;
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ulong scaled = xBits & ((1ul << 52) - 1);
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if (xExp >= 2045)
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{
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if (xExp == 0x7ff && scaled != 0)
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{
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// NaN
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return BitConverter.Int64BitsToDouble((long)(xBits | 0x0008000000000000));
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}
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// Infinity, or Out of range -> Zero
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return BitConverter.Int64BitsToDouble((long)xSign);
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}
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if (xExp == 0)
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{
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if (scaled == 0)
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{
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// Zero -> Infinity
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return BitConverter.Int64BitsToDouble((long)(xSign | 0x7FF0000000000000));
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}
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// Denormal
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if ((scaled & (1ul << 51)) == 0)
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{
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xExp = ~0ul;
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scaled <<= 2;
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}
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else
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{
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scaled <<= 1;
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}
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}
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scaled >>= 44;
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scaled &= 0xFF;
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ulong resultExp = (2045 - xExp) & 0x7FF;
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ulong estimate = (ulong)RecipEstimateTable[scaled];
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ulong fraction = estimate << 44;
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if (resultExp == 0)
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{
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fraction >>= 1;
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fraction |= 1ul << 51;
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}
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else if (resultExp == 0x7FF)
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{
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resultExp = 0;
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fraction >>= 2;
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fraction |= 1ul << 50;
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}
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ulong result = xSign | (resultExp << 52) | fraction;
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return BitConverter.Int64BitsToDouble((long)result);
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}
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[MethodImpl(MethodImplOptions.AggressiveInlining)]
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public static float InvSqrtEstimate(float x)
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{
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return (float)InvSqrtEstimate((double)x);
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}
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public static double InvSqrtEstimate(double x)
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{
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ulong xBits = (ulong)BitConverter.DoubleToInt64Bits(x);
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ulong xSign = xBits & 0x8000000000000000;
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long xExp = (long)((xBits >> 52) & 0x7FF);
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ulong scaled = xBits & ((1ul << 52) - 1);
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if (xExp == 0x7FF && scaled != 0)
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{
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// NaN
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return BitConverter.Int64BitsToDouble((long)(xBits | 0x0008000000000000));
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}
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if (xExp == 0)
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{
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if (scaled == 0)
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{
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// Zero -> Infinity
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return BitConverter.Int64BitsToDouble((long)(xSign | 0x7FF0000000000000));
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}
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// Denormal
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while ((scaled & (1 << 51)) == 0)
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{
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scaled <<= 1;
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xExp--;
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}
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scaled <<= 1;
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}
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if (xSign != 0)
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{
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// Negative -> NaN
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return BitConverter.Int64BitsToDouble((long)0x7FF8000000000000);
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}
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if (xExp == 0x7ff && scaled == 0)
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{
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// Infinity -> Zero
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return BitConverter.Int64BitsToDouble((long)xSign);
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}
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if (((ulong)xExp & 1) == 1)
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{
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scaled >>= 45;
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scaled &= 0xFF;
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scaled |= 0x80;
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}
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else
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{
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scaled >>= 44;
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scaled &= 0xFF;
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scaled |= 0x100;
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}
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ulong resultExp = ((ulong)(3068 - xExp) / 2) & 0x7FF;
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ulong estimate = (ulong)InvSqrtEstimateTable[scaled];
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ulong fraction = estimate << 44;
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ulong result = xSign | (resultExp << 52) | fraction;
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return BitConverter.Int64BitsToDouble((long)result);
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}
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}
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static class SoftFloat1632
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{
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public static float FPConvert(ushort valueBits, CpuThreadState state)
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{
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Debug.WriteLineIf(state.Fpcr != 0, $"ASoftFloat16_32.FPConvert: State.Fpcr = 0x{state.Fpcr:X8}");
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double real = valueBits.FPUnpackCv(out FpType type, out bool sign, state);
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float result;
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if (type == FpType.SNaN || type == FpType.QNaN)
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{
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if (state.GetFpcrFlag(Fpcr.Dn))
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{
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result = FPDefaultNaN();
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}
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else
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{
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result = FPConvertNaN(valueBits);
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}
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if (type == FpType.SNaN)
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{
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FPProcessException(FpExc.InvalidOp, state);
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}
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}
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else if (type == FpType.Infinity)
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{
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result = FPInfinity(sign);
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}
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else if (type == FpType.Zero)
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{
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result = FPZero(sign);
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}
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else
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{
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result = FPRoundCv(real, state);
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}
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return result;
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}
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private static float FPDefaultNaN()
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{
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return -float.NaN;
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}
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private static float FPInfinity(bool sign)
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{
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return sign ? float.NegativeInfinity : float.PositiveInfinity;
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}
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private static float FPZero(bool sign)
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{
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return sign ? -0f : +0f;
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}
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private static float FPMaxNormal(bool sign)
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{
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return sign ? float.MinValue : float.MaxValue;
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}
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private static double FPUnpackCv(this ushort valueBits, out FpType type, out bool sign, CpuThreadState state)
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{
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sign = (~(uint)valueBits & 0x8000u) == 0u;
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uint exp16 = ((uint)valueBits & 0x7C00u) >> 10;
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uint frac16 = (uint)valueBits & 0x03FFu;
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double real;
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if (exp16 == 0u)
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{
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if (frac16 == 0u)
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{
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type = FpType.Zero;
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real = 0d;
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}
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else
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{
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type = FpType.Nonzero; // Subnormal.
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real = Math.Pow(2d, -14) * ((double)frac16 * Math.Pow(2d, -10));
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}
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}
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else if (exp16 == 0x1Fu && !state.GetFpcrFlag(Fpcr.Ahp))
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{
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if (frac16 == 0u)
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{
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type = FpType.Infinity;
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real = Math.Pow(2d, 1000);
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}
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else
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{
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type = (~frac16 & 0x0200u) == 0u ? FpType.QNaN : FpType.SNaN;
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real = 0d;
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}
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}
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else
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{
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type = FpType.Nonzero; // Normal.
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real = Math.Pow(2d, (int)exp16 - 15) * (1d + (double)frac16 * Math.Pow(2d, -10));
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}
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return sign ? -real : real;
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}
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private static float FPRoundCv(double real, CpuThreadState state)
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{
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const int minimumExp = -126;
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const int e = 8;
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const int f = 23;
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bool sign;
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double mantissa;
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if (real < 0d)
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{
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sign = true;
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mantissa = -real;
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}
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else
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{
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sign = false;
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mantissa = real;
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}
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int exponent = 0;
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while (mantissa < 1d)
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{
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mantissa *= 2d;
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exponent--;
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}
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while (mantissa >= 2d)
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{
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mantissa /= 2d;
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exponent++;
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}
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if (state.GetFpcrFlag(Fpcr.Fz) && exponent < minimumExp)
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{
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state.SetFpsrFlag(Fpsr.Ufc);
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return FPZero(sign);
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}
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uint biasedExp = (uint)Math.Max(exponent - minimumExp + 1, 0);
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if (biasedExp == 0u)
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{
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mantissa /= Math.Pow(2d, minimumExp - exponent);
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}
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uint intMant = (uint)Math.Floor(mantissa * Math.Pow(2d, f));
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double error = mantissa * Math.Pow(2d, f) - (double)intMant;
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if (biasedExp == 0u && (error != 0d || state.GetFpcrFlag(Fpcr.Ufe)))
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{
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FPProcessException(FpExc.Underflow, state);
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}
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bool overflowToInf;
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bool roundUp;
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switch (state.FPRoundingMode())
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{
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default:
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case RoundMode.ToNearest:
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roundUp = (error > 0.5d || (error == 0.5d && (intMant & 1u) == 1u));
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overflowToInf = true;
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break;
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case RoundMode.TowardsPlusInfinity:
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roundUp = (error != 0d && !sign);
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overflowToInf = !sign;
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break;
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case RoundMode.TowardsMinusInfinity:
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roundUp = (error != 0d && sign);
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overflowToInf = sign;
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break;
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case RoundMode.TowardsZero:
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roundUp = false;
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overflowToInf = false;
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break;
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}
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if (roundUp)
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{
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intMant++;
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if (intMant == (uint)Math.Pow(2d, f))
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{
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biasedExp = 1u;
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}
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if (intMant == (uint)Math.Pow(2d, f + 1))
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{
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biasedExp++;
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intMant >>= 1;
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}
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}
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float result;
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if (biasedExp >= (uint)Math.Pow(2d, e) - 1u)
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{
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result = overflowToInf ? FPInfinity(sign) : FPMaxNormal(sign);
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FPProcessException(FpExc.Overflow, state);
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error = 1d;
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}
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else
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{
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result = BitConverter.Int32BitsToSingle(
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(int)((sign ? 1u : 0u) << 31 | (biasedExp & 0xFFu) << 23 | (intMant & 0x007FFFFFu)));
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}
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if (error != 0d)
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{
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FPProcessException(FpExc.Inexact, state);
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}
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return result;
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}
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private static float FPConvertNaN(ushort valueBits)
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{
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return BitConverter.Int32BitsToSingle(
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(int)(((uint)valueBits & 0x8000u) << 16 | 0x7FC00000u | ((uint)valueBits & 0x01FFu) << 13));
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}
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private static void FPProcessException(FpExc exc, CpuThreadState state)
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{
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int enable = (int)exc + 8;
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if ((state.Fpcr & (1 << enable)) != 0)
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{
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throw new NotImplementedException("floating-point trap handling");
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}
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else
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{
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state.Fpsr |= 1 << (int)exc;
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}
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}
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}
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static class SoftFloat3216
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{
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public static ushort FPConvert(float value, CpuThreadState state)
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{
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Debug.WriteLineIf(state.Fpcr != 0, $"ASoftFloat32_16.FPConvert: State.Fpcr = 0x{state.Fpcr:X8}");
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double real = value.FPUnpackCv(out FpType type, out bool sign, state, out uint valueBits);
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bool altHp = state.GetFpcrFlag(Fpcr.Ahp);
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ushort resultBits;
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if (type == FpType.SNaN || type == FpType.QNaN)
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{
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if (altHp)
|
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{
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resultBits = FPZero(sign);
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}
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else if (state.GetFpcrFlag(Fpcr.Dn))
|
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{
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resultBits = FPDefaultNaN();
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}
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else
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{
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resultBits = FPConvertNaN(valueBits);
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}
|
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if (type == FpType.SNaN || altHp)
|
||
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{
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FPProcessException(FpExc.InvalidOp, state);
|
||
|
}
|
||
|
}
|
||
|
else if (type == FpType.Infinity)
|
||
|
{
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||
|
if (altHp)
|
||
|
{
|
||
|
resultBits = (ushort)((sign ? 1u : 0u) << 15 | 0x7FFFu);
|
||
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|
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|
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, CpuThreadState 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, CpuThreadState 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 RoundMode.ToNearest:
|
||
|
roundUp = (error > 0.5d || (error == 0.5d && (intMant & 1u) == 1u));
|
||
|
overflowToInf = true;
|
||
|
break;
|
||
|
|
||
|
case RoundMode.TowardsPlusInfinity:
|
||
|
roundUp = (error != 0d && !sign);
|
||
|
overflowToInf = !sign;
|
||
|
break;
|
||
|
|
||
|
case RoundMode.TowardsMinusInfinity:
|
||
|
roundUp = (error != 0d && sign);
|
||
|
overflowToInf = sign;
|
||
|
break;
|
||
|
|
||
|
case RoundMode.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, CpuThreadState 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 SoftFloat32
|
||
|
{
|
||
|
public static float FPAdd(float value1, float value2, CpuThreadState 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, CpuThreadState 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, CpuThreadState 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, CpuThreadState 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, CpuThreadState 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, CpuThreadState 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, CpuThreadState 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, CpuThreadState 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, CpuThreadState 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, CpuThreadState 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, CpuThreadState 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, CpuThreadState 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, CpuThreadState 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, CpuThreadState 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, CpuThreadState 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,
|
||
|
CpuThreadState 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,
|
||
|
CpuThreadState 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, CpuThreadState 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, CpuThreadState 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 SoftFloat64
|
||
|
{
|
||
|
public static double FPAdd(double value1, double value2, CpuThreadState 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, CpuThreadState 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, CpuThreadState 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, CpuThreadState 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, CpuThreadState 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, CpuThreadState 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, CpuThreadState 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, CpuThreadState 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, CpuThreadState 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, CpuThreadState 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, CpuThreadState 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, CpuThreadState 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, CpuThreadState 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, CpuThreadState 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, CpuThreadState 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,
|
||
|
CpuThreadState 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,
|
||
|
CpuThreadState 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, CpuThreadState 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, CpuThreadState 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;
|
||
|
}
|
||
|
}
|
||
|
}
|
||
|
}
|