ARMeilleure/Decoders/OpCode32.cs


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namespace ARMeilleure.Decoders
{
    class OpCode32 : OpCode
    {
        public Condition Cond { get; protected set; }

        public new static OpCode Create(InstDescriptor inst, ulong address, int opCode) => new OpCode32(inst, address, opCode);

        public OpCode32(InstDescriptor inst, ulong address, int opCode) : base(inst, address, opCode)
        {
            RegisterSize = RegisterSize.Int32;

            Cond = (Condition)((uint)opCode >> 28);
        }

        public bool IsThumb { get; protected init; } = false;

        public uint GetPc()
        {
            // Due to backwards compatibility and legacy behavior of ARMv4 CPUs pipeline,
            // the PC actually points 2 instructions ahead.
            if (IsThumb)
            {
                // PC is ahead by 4 in thumb mode whether or not the current instruction
                // is 16 or 32 bit.
                return (uint)Address + 4u;
            }
            else
            {
                return (uint)Address + 8u;
            }
        }
    }
}