Function ExtractRegister

arch/arm64/il.cpp:133–166

extractSize can be smaller than the register, generating an LLIL_LOWPART resultSize can be larger than the register, generating sign or zero extension

// extractSize can be smaller than the register, generating an LLIL_LOWPART
// resultSize can be larger than the register, generating sign or zero extension
ExprId ExtractRegister(LowLevelILFunction& il, InstructionOperand& operand, size_t regNum,
    size_t extractSize, bool signExtend, size_t resultSize)
{
	size_t opsz = get_register_size(operand.reg[regNum]);

	if (IS_ZERO_REG(operand.reg[regNum]))
	    return il.Const(resultSize, 0);

	ExprId res = 0;

	switch (operand.operandClass)
	{
	case SYS_REG:
		res = il.Register(opsz, operand.sysreg);
		break;
	case REG:
	default:
		res = il.Register(opsz, operand.reg[regNum]);
		break;
	}

	if (extractSize < opsz)
		res = il.LowPart(extractSize, res);

	if (extractSize < resultSize || opsz < extractSize)
	{
		if (signExtend)
			res = il.SignExtend(resultSize, res);
		else
			res = il.ZeroExtend(resultSize, res);
	}

	return res;
}

static ExprId GetFloat(LowLevelILFunction& il, InstructionOperand& operand, int float_sz)
{