ChocolArm64/Decoders/OpCodeSimdMemSs64.cs

97 lines
2.3 KiB
C#
Raw Normal View History

using ChocolArm64.Instructions;
namespace ChocolArm64.Decoders
{
class OpCodeSimdMemSs64 : OpCodeMemReg64, IOpCodeSimd64
{
public int SElems { get; private set; }
public int Index { get; private set; }
public bool Replicate { get; private set; }
public bool WBack { get; private set; }
public OpCodeSimdMemSs64(Inst inst, long position, int opCode) : base(inst, position, opCode)
{
int size = (opCode >> 10) & 3;
int s = (opCode >> 12) & 1;
int sElems = (opCode >> 12) & 2;
int scale = (opCode >> 14) & 3;
int l = (opCode >> 22) & 1;
int q = (opCode >> 30) & 1;
sElems |= (opCode >> 21) & 1;
sElems++;
int index = (q << 3) | (s << 2) | size;
switch (scale)
{
case 1:
{
if ((size & 1) != 0)
{
inst = Inst.Undefined;
return;
}
index >>= 1;
break;
}
case 2:
{
if ((size & 2) != 0 ||
((size & 1) != 0 && s != 0))
{
inst = Inst.Undefined;
return;
}
if ((size & 1) != 0)
{
index >>= 3;
scale = 3;
}
else
{
index >>= 2;
}
break;
}
case 3:
{
if (l == 0 || s != 0)
{
inst = Inst.Undefined;
return;
}
scale = size;
Replicate = true;
break;
}
}
Index = index;
SElems = sElems;
Size = scale;
Extend64 = false;
WBack = ((opCode >> 23) & 1) != 0;
RegisterSize = q != 0
? State.RegisterSize.Simd128
: State.RegisterSize.Simd64;
}
}
}