Ryujinx/ChocolArm64/Instruction/ASoftFallback.cs
LDj3SNuD be31f5b46d Improve CountLeadingZeros() algorithm, nits. (#219)
* Update AInstEmitSimdArithmetic.cs

* Update ASoftFallback.cs

* Update ASoftFallback.cs

* Update ASoftFallback.cs

* Update AInstEmitSimdArithmetic.cs
2018-07-14 15:07:44 -03:00

216 lines
7.2 KiB
C#

using ChocolArm64.Translation;
using System;
namespace ChocolArm64.Instruction
{
static class ASoftFallback
{
public static void EmitCall(AILEmitterCtx Context, string MthdName)
{
Context.EmitCall(typeof(ASoftFallback), MthdName);
}
public static ulong CountLeadingSigns(ulong Value, int Size)
{
Value ^= Value >> 1;
int HighBit = Size - 2;
for (int Bit = HighBit; Bit >= 0; Bit--)
{
if (((Value >> Bit) & 0b1) != 0)
{
return (ulong)(HighBit - Bit);
}
}
return (ulong)(Size - 1);
}
private static readonly byte[] ClzNibbleTbl = { 4, 3, 2, 2, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0 };
public static ulong CountLeadingZeros(ulong Value, int Size)
{
if (Value == 0)
{
return (ulong)Size;
}
int NibbleIdx = Size;
int PreCount, Count = 0;
do
{
NibbleIdx -= 4;
PreCount = ClzNibbleTbl[(Value >> NibbleIdx) & 0b1111];
Count += PreCount;
}
while (PreCount == 4);
return (ulong)Count;
}
public static uint CountSetBits8(uint Value)
{
Value = ((Value >> 1) & 0x55) + (Value & 0x55);
Value = ((Value >> 2) & 0x33) + (Value & 0x33);
return (Value >> 4) + (Value & 0x0f);
}
private const uint Crc32RevPoly = 0xedb88320;
private const uint Crc32cRevPoly = 0x82f63b78;
public static uint Crc32b(uint Crc, byte Val) => Crc32 (Crc, Crc32RevPoly, Val);
public static uint Crc32h(uint Crc, ushort Val) => Crc32h(Crc, Crc32RevPoly, Val);
public static uint Crc32w(uint Crc, uint Val) => Crc32w(Crc, Crc32RevPoly, Val);
public static uint Crc32x(uint Crc, ulong Val) => Crc32x(Crc, Crc32RevPoly, Val);
public static uint Crc32cb(uint Crc, byte Val) => Crc32 (Crc, Crc32cRevPoly, Val);
public static uint Crc32ch(uint Crc, ushort Val) => Crc32h(Crc, Crc32cRevPoly, Val);
public static uint Crc32cw(uint Crc, uint Val) => Crc32w(Crc, Crc32cRevPoly, Val);
public static uint Crc32cx(uint Crc, ulong Val) => Crc32x(Crc, Crc32cRevPoly, Val);
private static uint Crc32h(uint Crc, uint Poly, ushort Val)
{
Crc = Crc32(Crc, Poly, (byte)(Val >> 0));
Crc = Crc32(Crc, Poly, (byte)(Val >> 8));
return Crc;
}
private static uint Crc32w(uint Crc, uint Poly, uint Val)
{
Crc = Crc32(Crc, Poly, (byte)(Val >> 0 ));
Crc = Crc32(Crc, Poly, (byte)(Val >> 8 ));
Crc = Crc32(Crc, Poly, (byte)(Val >> 16));
Crc = Crc32(Crc, Poly, (byte)(Val >> 24));
return Crc;
}
private static uint Crc32x(uint Crc, uint Poly, ulong Val)
{
Crc = Crc32(Crc, Poly, (byte)(Val >> 0 ));
Crc = Crc32(Crc, Poly, (byte)(Val >> 8 ));
Crc = Crc32(Crc, Poly, (byte)(Val >> 16));
Crc = Crc32(Crc, Poly, (byte)(Val >> 24));
Crc = Crc32(Crc, Poly, (byte)(Val >> 32));
Crc = Crc32(Crc, Poly, (byte)(Val >> 40));
Crc = Crc32(Crc, Poly, (byte)(Val >> 48));
Crc = Crc32(Crc, Poly, (byte)(Val >> 56));
return Crc;
}
private static uint Crc32(uint Crc, uint Poly, byte Val)
{
Crc ^= Val;
for (int Bit = 7; Bit >= 0; Bit--)
{
uint Mask = (uint)(-(int)(Crc & 1));
Crc = (Crc >> 1) ^ (Poly & Mask);
}
return Crc;
}
public static uint ReverseBits8(uint Value)
{
Value = ((Value & 0xaa) >> 1) | ((Value & 0x55) << 1);
Value = ((Value & 0xcc) >> 2) | ((Value & 0x33) << 2);
return (Value >> 4) | ((Value & 0x0f) << 4);
}
public static uint ReverseBits32(uint Value)
{
Value = ((Value & 0xaaaaaaaa) >> 1) | ((Value & 0x55555555) << 1);
Value = ((Value & 0xcccccccc) >> 2) | ((Value & 0x33333333) << 2);
Value = ((Value & 0xf0f0f0f0) >> 4) | ((Value & 0x0f0f0f0f) << 4);
Value = ((Value & 0xff00ff00) >> 8) | ((Value & 0x00ff00ff) << 8);
return (Value >> 16) | (Value << 16);
}
public static ulong ReverseBits64(ulong Value)
{
Value = ((Value & 0xaaaaaaaaaaaaaaaa) >> 1 ) | ((Value & 0x5555555555555555) << 1 );
Value = ((Value & 0xcccccccccccccccc) >> 2 ) | ((Value & 0x3333333333333333) << 2 );
Value = ((Value & 0xf0f0f0f0f0f0f0f0) >> 4 ) | ((Value & 0x0f0f0f0f0f0f0f0f) << 4 );
Value = ((Value & 0xff00ff00ff00ff00) >> 8 ) | ((Value & 0x00ff00ff00ff00ff) << 8 );
Value = ((Value & 0xffff0000ffff0000) >> 16) | ((Value & 0x0000ffff0000ffff) << 16);
return (Value >> 32) | (Value << 32);
}
public static uint ReverseBytes16_32(uint Value) => (uint)ReverseBytes16_64(Value);
public static uint ReverseBytes32_32(uint Value) => (uint)ReverseBytes32_64(Value);
public static ulong ReverseBytes16_64(ulong Value) => ReverseBytes(Value, RevSize.Rev16);
public static ulong ReverseBytes32_64(ulong Value) => ReverseBytes(Value, RevSize.Rev32);
public static ulong ReverseBytes64(ulong Value) => ReverseBytes(Value, RevSize.Rev64);
private enum RevSize
{
Rev16,
Rev32,
Rev64
}
private static ulong ReverseBytes(ulong Value, RevSize Size)
{
Value = ((Value & 0xff00ff00ff00ff00) >> 8) | ((Value & 0x00ff00ff00ff00ff) << 8);
if (Size == RevSize.Rev16)
{
return Value;
}
Value = ((Value & 0xffff0000ffff0000) >> 16) | ((Value & 0x0000ffff0000ffff) << 16);
if (Size == RevSize.Rev32)
{
return Value;
}
Value = ((Value & 0xffffffff00000000) >> 32) | ((Value & 0x00000000ffffffff) << 32);
if (Size == RevSize.Rev64)
{
return Value;
}
throw new ArgumentException(nameof(Size));
}
public static long SMulHi128(long LHS, long RHS)
{
long Result = (long)UMulHi128((ulong)LHS, (ulong)RHS);
if (LHS < 0) Result -= RHS;
if (RHS < 0) Result -= LHS;
return Result;
}
public static ulong UMulHi128(ulong LHS, ulong RHS)
{
//long multiplication
//multiply 32 bits at a time in 64 bit, the result is what's carried over 64 bits.
ulong LHigh = LHS >> 32;
ulong LLow = LHS & 0xFFFFFFFF;
ulong RHigh = RHS >> 32;
ulong RLow = RHS & 0xFFFFFFFF;
ulong Z2 = LLow * RLow;
ulong T = LHigh * RLow + (Z2 >> 32);
ulong Z1 = T & 0xFFFFFFFF;
ulong Z0 = T >> 32;
Z1 += LLow * RHigh;
return LHigh * RHigh + Z0 + (Z1 >> 32);
}
}
}