div.c revision 2
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pragma ident "%Z%%M% %I% %E% SMI" 2N/A * The ANSI standard says that |r.quot| <= |n/d|, where 2N/A * n/d is to be computed in infinite precision. In other 2N/A * words, we should always truncate the quotient towards 2N/A * 0, never -infinity. 2N/A * Machine division and remainer may work either way when 2N/A * one or both of n or d is negative. If only one is 2N/A * negative and r.quot has been truncated towards -inf, 2N/A * r.rem will have the same sign as denom and the opposite 2N/A * sign of num; if both are negative and r.quot has been 2N/A * truncated towards -inf, r.rem will be positive (will 2N/A * have the opposite sign of num). These are considered 2N/A * If both are num and denom are positive, r will always 2N/A * This all boils down to: 2N/A * if num >= 0, but r.rem < 0, we got the wrong answer. 2N/A * In that case, to get the right answer, add 1 to r.quot and 2N/A * subtract denom from r.rem. 2N/A /* see div() for comments */