SW_Precision
if (partial_status & SW_Precision)
partial_status & SW_Precision ? 1 : 0,
control_word & SW_Precision ? 1 : 0,
partial_status |= (SW_Precision | SW_C1); /* The masked response */
partial_status |= SW_Precision;
~(SW_Backward | SW_Summary | SW_Stack_Fault | SW_Precision |