##smaddl_execute
bits(datasize) operand1 = X[n];
bits(datasize) operand2 = X[m];
bits(destsize) operand3 = X[a];

integer result;

if sub_op then
    result = Int(operand3, true) - (Int(operand1, true) * Int(operand2, true));
else
    result = Int(operand3, true) + (Int(operand1, true) * Int(operand2, true));
end

X[d] = result<63:0>;
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