Ryujinx/ARMeilleure/Decoders/OpCodeT32MemMult.cs
gdkchan eba682b767
Implement some 32-bit Thumb instructions (#3614)
* Implement some 32-bit Thumb instructions

* Optimize OpCode32MemMult using PopCount
2022-08-25 09:59:34 +00:00

52 lines
1.3 KiB
C#

using System.Numerics;
namespace ARMeilleure.Decoders
{
class OpCodeT32MemMult : OpCodeT32, IOpCode32MemMult
{
public int Rn { get; }
public int RegisterMask { get; }
public int Offset { get; }
public int PostOffset { get; }
public bool IsLoad { get; }
public new static OpCode Create(InstDescriptor inst, ulong address, int opCode) => new OpCodeT32MemMult(inst, address, opCode);
public OpCodeT32MemMult(InstDescriptor inst, ulong address, int opCode) : base(inst, address, opCode)
{
Rn = (opCode >> 16) & 0xf;
bool isLoad = (opCode & (1 << 20)) != 0;
bool w = (opCode & (1 << 21)) != 0;
bool u = (opCode & (1 << 23)) != 0;
bool p = (opCode & (1 << 24)) != 0;
RegisterMask = opCode & 0xffff;
int regsSize = BitOperations.PopCount((uint)RegisterMask) * 4;
if (!u)
{
Offset -= regsSize;
}
if (u == p)
{
Offset += 4;
}
if (w)
{
PostOffset = u ? regsSize : -regsSize;
}
else
{
PostOffset = 0;
}
IsLoad = isLoad;
}
}
}