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authorPeter Breitenlohner <peb@mppmu.mpg.de>2014-06-18 11:12:01 +0000
committerPeter Breitenlohner <peb@mppmu.mpg.de>2014-06-18 11:12:01 +0000
commit0c2f0333a4e539325da80cdf3fb182cd17134665 (patch)
treede5daa66b5595292a33c25110aa58ff8bff75543 /Build/source/libs/gmp/gmp-6.0.0/mpf/eq.c
parentdb612d5045ef55da386a2c3350d4811d1da1a858 (diff)
Add libs/gmp and libs/mpfr in preparation for MetaPost 2.0
git-svn-id: svn://tug.org/texlive/trunk@34274 c570f23f-e606-0410-a88d-b1316a301751
Diffstat (limited to 'Build/source/libs/gmp/gmp-6.0.0/mpf/eq.c')
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1 files changed, 150 insertions, 0 deletions
diff --git a/Build/source/libs/gmp/gmp-6.0.0/mpf/eq.c b/Build/source/libs/gmp/gmp-6.0.0/mpf/eq.c
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index 00000000000..30c6befd061
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+++ b/Build/source/libs/gmp/gmp-6.0.0/mpf/eq.c
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+/* mpf_eq -- Compare two floats up to a specified bit #.
+
+Copyright 1993, 1995, 1996, 2001, 2002, 2008, 2009, 2012 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 either:
+
+ * 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.
+
+or
+
+ * the GNU General Public License as published by the Free Software
+ Foundation; either version 2 of the License, or (at your option) any
+ later version.
+
+or both in parallel, as here.
+
+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 copies of the GNU General Public License and the
+GNU Lesser General Public License along with the GNU MP Library. If not,
+see https://www.gnu.org/licenses/. */
+
+#include "gmp.h"
+#include "gmp-impl.h"
+#include "longlong.h"
+
+int
+mpf_eq (mpf_srcptr u, mpf_srcptr v, mp_bitcnt_t n_bits)
+{
+ mp_srcptr up, vp, p;
+ mp_size_t usize, vsize, minsize, maxsize, n_limbs, i, size;
+ mp_exp_t uexp, vexp;
+ mp_limb_t diff;
+ int cnt;
+
+ 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)
+ return vsize == 0;
+ if (vsize == 0)
+ return 0;
+
+ /* Fall out. */
+ }
+ else
+ {
+ /* Either U or V is negative, but not both. */
+ return 0;
+ }
+
+ /* U and V have the same sign and are both non-zero. */
+
+ /* 2. Are the exponents different? */
+ if (uexp != vexp)
+ return 0;
+
+ usize = ABS (usize);
+ vsize = ABS (vsize);
+
+ up = u->_mp_d;
+ vp = v->_mp_d;
+
+ up += usize; /* point just above most significant limb */
+ vp += vsize; /* point just above most significant limb */
+
+ count_leading_zeros (cnt, up[-1]);
+ if ((vp[-1] >> (GMP_LIMB_BITS - 1 - cnt)) != 1)
+ return 0; /* msb positions different */
+
+ n_bits += cnt - GMP_NAIL_BITS;
+ n_limbs = (n_bits + GMP_NUMB_BITS - 1) / GMP_NUMB_BITS;
+
+ usize = MIN (usize, n_limbs);
+ vsize = MIN (vsize, n_limbs);
+
+#if 0
+ /* Ignore zeros at the low end of U and V. */
+ while (up[0] == 0)
+ up++, usize--;
+ while (vp[0] == 0)
+ vp++, vsize--;
+#endif
+
+ minsize = MIN (usize, vsize);
+ maxsize = usize + vsize - minsize;
+
+ up -= minsize; /* point at most significant common limb */
+ vp -= minsize; /* point at most significant common limb */
+
+ /* Compare the most significant part which has explicit limbs for U and V. */
+ for (i = minsize - 1; i > 0; i--)
+ {
+ if (up[i] != vp[i])
+ return 0;
+ }
+
+ n_bits -= (maxsize - 1) * GMP_NUMB_BITS;
+
+ size = maxsize - minsize;
+ if (size != 0)
+ {
+ if (up[0] != vp[0])
+ return 0;
+
+ /* Now either U or V has its limbs consumed, i.e, continues with an
+ infinite number of implicit zero limbs. Check that the other operand
+ has just zeros in the corresponding, relevant part. */
+
+ if (usize > vsize)
+ p = up - size;
+ else
+ p = vp - size;
+
+ for (i = size - 1; i > 0; i--)
+ {
+ if (p[i] != 0)
+ return 0;
+ }
+
+ diff = p[0];
+ }
+ else
+ {
+ /* Both U or V has its limbs consumed. */
+
+ diff = up[0] ^ vp[0];
+ }
+
+ if (n_bits < GMP_NUMB_BITS)
+ diff >>= GMP_NUMB_BITS - n_bits;
+
+ return diff == 0;
+}