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-rw-r--r--mpf/cmp.c114
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+/* mpf_cmp -- Compare two floats.
+
+Copyright (C) 1993, 1994, 1996 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 Library General Public License as published by
+the Free Software Foundation; either version 2 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 Library General Public
+License for more details.
+
+You should have received a copy of the GNU Library General Public License
+along with the GNU MP Library; see the file COPYING.LIB. If not, write to
+the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
+MA 02111-1307, USA. */
+
+#include "gmp.h"
+#include "gmp-impl.h"
+
+int
+#if __STDC__
+mpf_cmp (mpf_srcptr u, mpf_srcptr v)
+#else
+mpf_cmp (u, v)
+ mpf_srcptr u;
+ mpf_srcptr v;
+#endif
+{
+ mp_srcptr up, vp;
+ mp_size_t usize, vsize;
+ mp_exp_t uexp, vexp;
+ int cmp;
+ int usign;
+
+ uexp = u->_mp_exp;
+ vexp = v->_mp_exp;
+
+ usize = u->_mp_size;
+ vsize = v->_mp_size;
+
+ /* 1. Are the signs different? */
+ if ((usize ^ vsize) >= 0)
+ {
+ /* U and V are both non-negative or both negative. */
+ if (usize == 0)
+ /* vsize >= 0 */
+ return -(vsize != 0);
+ if (vsize == 0)
+ /* usize >= 0 */
+ return usize != 0;
+ /* Fall out. */
+ }
+ else
+ {
+ /* Either U or V is negative, but not both. */
+ return usize >= 0 ? 1 : -1;
+ }
+
+ /* U and V have the same sign and are both non-zero. */
+
+ usign = usize >= 0 ? 1 : -1;
+
+ /* 2. Are the exponents different? */
+ if (uexp > vexp)
+ return usign;
+ if (uexp < vexp)
+ return -usign;
+
+ usize = ABS (usize);
+ vsize = ABS (vsize);
+
+ up = u->_mp_d;
+ vp = v->_mp_d;
+
+#define STRICT_MPF_NORMALIZATION 0
+#if ! STRICT_MPF_NORMALIZATION
+ /* Ignore zeroes at the low end of U and V. */
+ while (up[0] == 0)
+ {
+ up++;
+ usize--;
+ }
+ while (vp[0] == 0)
+ {
+ vp++;
+ vsize--;
+ }
+#endif
+
+ if (usize > vsize)
+ {
+ cmp = mpn_cmp (up + usize - vsize, vp, vsize);
+ if (cmp == 0)
+ return usign;
+ }
+ else if (vsize > usize)
+ {
+ cmp = mpn_cmp (up, vp + vsize - usize, usize);
+ if (cmp == 0)
+ return -usign;
+ }
+ else
+ {
+ cmp = mpn_cmp (up, vp, usize);
+ if (cmp == 0)
+ return 0;
+ }
+ return cmp > 0 ? usign : -usign;
+}