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authorpartain <unknown>1996-01-08 20:28:12 +0000
committerpartain <unknown>1996-01-08 20:28:12 +0000
commite7d21ee4f8ac907665a7e170c71d59e13a01da09 (patch)
tree93715bf4e6e4bbe8049e4d8d4d3fbd19158a88d6 /ghc/runtime/gmp/mpz_mdm.c
parente48474bff05e6cfb506660420f025f694c870d38 (diff)
downloadhaskell-e7d21ee4f8ac907665a7e170c71d59e13a01da09.tar.gz
[project @ 1996-01-08 20:28:12 by partain]
Initial revision
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+/* mpz_mdivmod -- Mathematical DIVision and MODulo, i.e. division that rounds
+ the quotient towards -infinity, and with the remainder non-negative.
+
+Copyright (C) 1991, 1992 Free Software Foundation, Inc.
+
+This file is part of the GNU MP Library.
+
+The GNU MP Library is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2, or (at your option)
+any later version.
+
+The GNU MP Library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with the GNU MP Library; see the file COPYING. If not, write to
+the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */
+
+#include "gmp.h"
+#include "gmp-impl.h"
+
+void
+#ifdef __STDC__
+mpz_mdivmod (MP_INT *quot, MP_INT *rem,
+ const MP_INT *dividend, const MP_INT *divisor)
+#else
+mpz_mdivmod (quot, rem, dividend, divisor)
+ MP_INT *quot;
+ MP_INT *rem;
+ const MP_INT *dividend;
+ const MP_INT *divisor;
+#endif
+{
+ if ((dividend->size ^ divisor->size) >= 0)
+ {
+ /* When the dividend and the divisor has same sign, this function
+ gives same result as mpz_divmod. */
+ mpz_divmod (quot, rem, dividend, divisor);
+ }
+ else
+ {
+ MP_INT temp_divisor; /* N.B.: lives until function returns! */
+
+ /* We need the original value of the divisor after the quotient and
+ remainder have been preliminary calculated. We have to copy it to
+ temporary space if it's the same variable as either QUOT or REM. */
+ if (quot == divisor || rem == divisor)
+ {
+ MPZ_TMP_INIT (&temp_divisor, ABS (divisor->size));
+ mpz_set (&temp_divisor, divisor);
+ divisor = &temp_divisor;
+ }
+
+ mpz_divmod (quot, rem, dividend, divisor);
+ if (rem->size != 0)
+ {
+ mpz_sub_ui (quot, quot, 1);
+ mpz_add (rem, rem, divisor);
+ }
+ }
+}