Imported gcc-4.4.3

[msp430-gcc.git] / gmp / mpq / mul.c

diff --git a/gmp/mpq/mul.c b/gmp/mpq/mul.c
new file mode 100644 (file)
index 0000000..0214b31
--- /dev/null
+++ b/gmp/mpq/mul.c
@@ -0,0 +1,93 @@
+/* mpq_mul -- multiply two rational numbers.
+
+Copyright 1991, 1994, 1995, 1996, 2000, 2001, 2002 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 Lesser General Public License as published by
+the Free Software Foundation; either version 3 of the License, 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 Lesser General Public
+License for more details.
+
+You should have received a copy of the GNU Lesser General Public License
+along with the GNU MP Library.  If not, see http://www.gnu.org/licenses/.  */
+
+#include "gmp.h"
+#include "gmp-impl.h"
+
+
+void
+mpq_mul (mpq_ptr prod, mpq_srcptr op1, mpq_srcptr op2)
+{
+  mpz_t gcd1, gcd2;
+  mpz_t tmp1, tmp2;
+  mp_size_t op1_num_size;
+  mp_size_t op1_den_size;
+  mp_size_t op2_num_size;
+  mp_size_t op2_den_size;
+  mp_size_t alloc;
+  TMP_DECL;
+
+  if (op1 == op2)
+    {
+      /* No need for any GCDs when squaring. */
+      mpz_mul (mpq_numref (prod), mpq_numref (op1), mpq_numref (op1));
+      mpz_mul (mpq_denref (prod), mpq_denref (op1), mpq_denref (op1));
+      return;
+    }
+
+  op1_num_size = ABS (op1->_mp_num._mp_size);
+  op1_den_size =      op1->_mp_den._mp_size;
+  op2_num_size = ABS (op2->_mp_num._mp_size);
+  op2_den_size =      op2->_mp_den._mp_size;
+
+  if (op1_num_size == 0 || op2_num_size == 0)
+    {
+      /* We special case this to simplify allocation logic; gcd(0,x) = x
+        is a singular case for the allocations.  */
+      prod->_mp_num._mp_size = 0;
+      prod->_mp_den._mp_d[0] = 1;
+      prod->_mp_den._mp_size = 1;
+      return;
+    }
+
+  TMP_MARK;
+
+  alloc = MIN (op1_num_size, op2_den_size);
+  MPZ_TMP_INIT (gcd1, alloc);
+
+  alloc = MIN (op2_num_size, op1_den_size);
+  MPZ_TMP_INIT (gcd2, alloc);
+
+  alloc = MAX (op1_num_size, op2_den_size);
+  MPZ_TMP_INIT (tmp1, alloc);
+
+  alloc = MAX (op2_num_size, op1_den_size);
+  MPZ_TMP_INIT (tmp2, alloc);
+
+  /* PROD might be identical to either operand, so don't store the result there
+     until we are finished with the input operands.  We can overwrite the
+     numerator of PROD when we are finished with the numerators of OP1 and
+     OP2.  */
+
+  mpz_gcd (gcd1, &(op1->_mp_num), &(op2->_mp_den));
+  mpz_gcd (gcd2, &(op2->_mp_num), &(op1->_mp_den));
+
+  mpz_divexact_gcd (tmp1, &(op1->_mp_num), gcd1);
+  mpz_divexact_gcd (tmp2, &(op2->_mp_num), gcd2);
+
+  mpz_mul (&(prod->_mp_num), tmp1, tmp2);
+
+  mpz_divexact_gcd (tmp1, &(op2->_mp_den), gcd1);
+  mpz_divexact_gcd (tmp2, &(op1->_mp_den), gcd2);
+
+  mpz_mul (&(prod->_mp_den), tmp1, tmp2);
+
+  TMP_FREE;
+}