[project @ 1996-01-08 20:28:12 by partain]

[ghc-hetmet.git] / ghc / runtime / gmp / mpq_cmp.c

diff --git a/ghc/runtime/gmp/mpq_cmp.c b/ghc/runtime/gmp/mpq_cmp.c
new file mode 100644 (file)
index 0000000..fd6abcc
--- /dev/null
+++ b/ghc/runtime/gmp/mpq_cmp.c
@@ -0,0 +1,76 @@
+/* mpq_cmp(u,v) -- Compare U, V.  Return positive, zero, or negative
+   based on if U > V, U == V, or U < V.
+
+Copyright (C) 1991 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"
+
+int
+#ifdef __STDC__
+mpq_cmp (const MP_RAT *op1, const MP_RAT *op2)
+#else
+mpq_cmp (op1, op2)
+     const MP_RAT *op1;
+     const MP_RAT *op2;
+#endif
+{
+  mp_size num1_size = op1->num.size;
+  mp_size den1_size = op1->den.size;
+  mp_size num2_size = op2->num.size;
+  mp_size den2_size = op2->den.size;
+  mp_size tmp1_size, tmp2_size;
+  mp_ptr tmp1_ptr, tmp2_ptr;
+  mp_size num1_sign;
+  int cc;
+
+  if (num1_size == 0)
+    return -num2_size;
+  if (num2_size == 0)
+    return num1_size;
+  if ((num1_size ^ num2_size) < 0) /* I.e. are the signs different? */
+    return num1_size;
+
+  num1_sign = num1_size;
+  num1_size = ABS (num1_size);
+  num2_size = ABS (num2_size);
+
+  tmp1_size = num1_size + den2_size;
+  tmp2_size = num2_size + den1_size;
+
+  if (tmp1_size != tmp2_size)
+    return (tmp1_size - tmp2_size) ^ num1_sign;
+
+  tmp1_ptr = (mp_ptr) alloca (tmp1_size * BYTES_PER_MP_LIMB);
+  tmp2_ptr = (mp_ptr) alloca (tmp2_size * BYTES_PER_MP_LIMB);
+
+  tmp1_size = (num1_size >= den2_size)
+    ? mpn_mul (tmp1_ptr, op1->num.d, num1_size, op2->den.d, den2_size)
+    : mpn_mul (tmp1_ptr, op2->den.d, den2_size, op1->num.d, num1_size);
+
+  tmp2_size = (num2_size >= den1_size)
+    ? mpn_mul (tmp2_ptr, op2->num.d, num2_size, op1->den.d, den1_size)
+    : mpn_mul (tmp2_ptr, op1->den.d, den1_size, op2->num.d, num2_size);
+
+  cc = tmp1_size - tmp2_size != 0
+    ? tmp1_size - tmp2_size : mpn_cmp (tmp1_ptr, tmp2_ptr, tmp1_size);
+
+  alloca (0);
+  return (num1_sign < 0) ? -cc : cc;
+}