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-rw-r--r--vendor/gmp-6.3.0/mpz/ui_sub.c90
1 files changed, 90 insertions, 0 deletions
diff --git a/vendor/gmp-6.3.0/mpz/ui_sub.c b/vendor/gmp-6.3.0/mpz/ui_sub.c
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+/* mpz_ui_sub -- Subtract an unsigned one-word integer and an mpz_t.
+
+Copyright 2002, 2004, 2015 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-impl.h"
+
+void
+mpz_ui_sub (mpz_ptr w, unsigned long int uval, mpz_srcptr v)
+{
+ mp_ptr vp, wp;
+ mp_size_t vn, wn;
+ mp_limb_t cy;
+
+#if BITS_PER_ULONG > GMP_NUMB_BITS /* avoid warnings about shift amount */
+ if (uval > GMP_NUMB_MAX)
+ {
+ mpz_t u;
+ mp_limb_t ul[2];
+ PTR(u) = ul;
+ ul[0] = uval & GMP_NUMB_MASK;
+ ul[1] = uval >> GMP_NUMB_BITS;
+ SIZ(u) = 2;
+ mpz_sub (w, u, v);
+ return;
+ }
+#endif
+
+ vn = SIZ(v);
+
+ if (vn > 1)
+ {
+ wp = MPZ_REALLOC (w, vn);
+ vp = PTR(v);
+ mpn_sub_1 (wp, vp, vn, (mp_limb_t) uval);
+ wn = -(vn - (wp[vn - 1] == 0));
+ }
+ else if (vn >= 0)
+ {
+ mp_limb_t vp0;
+ vp0 = PTR (v)[0] & - (mp_limb_t) vn;
+ wp = MPZ_NEWALLOC (w, 1);
+ if (uval >= vp0)
+ {
+ wp[0] = uval - vp0;
+ wn = wp[0] != 0;
+ }
+ else
+ {
+ wp[0] = vp0 - uval;
+ wn = -1;
+ }
+ }
+ else /* (vn < 0) */
+ {
+ vn = -vn;
+ wp = MPZ_REALLOC (w, vn + 1);
+ vp = PTR(v);
+ cy = mpn_add_1 (wp, vp, vn, (mp_limb_t) uval);
+ wp[vn] = cy;
+ wn = vn + (cy != 0);
+ }
+
+ SIZ(w) = wn;
+}