rjx-mirror/Ryujinx/Cpu/Decoder/AOpCodeSimdImm.cs

94 lines
No EOL
3 KiB
C#

using ChocolArm64.Instruction;
using ChocolArm64.State;
namespace ChocolArm64.Decoder
{
class AOpCodeSimdImm : AOpCode, IAOpCodeSimd
{
public int Rd { get; private set; }
public long Imm { get; private set; }
public int Size { get; private set; }
public AOpCodeSimdImm(AInst Inst, long Position, int OpCode) : base(Inst, Position, OpCode)
{
Rd = OpCode & 0x1f;
int CMode = (OpCode >> 12) & 0xf;
int Op = (OpCode >> 29) & 0x1;
int ModeLow = CMode & 1;
int ModeHigh = CMode >> 1;
long Imm;
Imm = ((uint)OpCode >> 5) & 0x1f;
Imm |= ((uint)OpCode >> 11) & 0xe0;
if (ModeHigh == 0b111)
{
Size = ModeLow != 0 ? Op : 3;
switch (Op | (ModeLow << 1))
{
case 0:
//64-bits Immediate.
//Transform abcd efgh into abcd efgh abcd efgh ...
Imm = (long)((ulong)Imm * 0x0101010101010101);
break;
case 1:
//64-bits Immediate.
//Transform abcd efgh into aaaa aaaa bbbb bbbb ...
Imm = (Imm & 0xf0) >> 4 | (Imm & 0x0f) << 4;
Imm = (Imm & 0xcc) >> 2 | (Imm & 0x33) << 2;
Imm = (Imm & 0xaa) >> 1 | (Imm & 0x55) << 1;
Imm = (long)((ulong)Imm * 0x8040201008040201);
Imm = (long)((ulong)Imm & 0x8080808080808080);
Imm |= Imm >> 4;
Imm |= Imm >> 2;
Imm |= Imm >> 1;
break;
case 2:
case 3:
//Floating point Immediate.
Imm = ADecoderHelper.DecodeImm8Float(Imm, Size);
break;
}
}
else if ((ModeHigh & 0b110) == 0b100)
{
//16-bits shifted Immediate.
Size = 1; Imm <<= (ModeHigh & 1) << 3;
}
else if ((ModeHigh & 0b100) == 0b000)
{
//32-bits shifted Immediate.
Size = 2; Imm <<= ModeHigh << 3;
}
else if ((ModeHigh & 0b111) == 0b110)
{
//32-bits shifted Immediate (fill with ones).
Size = 2; Imm = ShlOnes(Imm, 8 << ModeLow);
}
else
{
//8 bits without shift.
Size = 0;
}
this.Imm = Imm;
RegisterSize = ((OpCode >> 30) & 1) != 0
? ARegisterSize.SIMD128
: ARegisterSize.SIMD64;
}
private static long ShlOnes(long Value, int Shift)
{
return Value << Shift | (long)(ulong.MaxValue >> (64 - Shift));
}
}
}