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authorKevin Ryde <user42@zip.com.au>2001-10-02 01:08:46 +0200
committerKevin Ryde <user42@zip.com.au>2001-10-02 01:08:46 +0200
commit07cf896c2f829c1dd6a5456aa7e710044a6e594a (patch)
tree51a4079cd2a37c6d276e444f50cddd9aaf2c6540 /mpz/aors_ui.h
parent9edc48e967f743b5438c9c47a481ded5f8c50069 (diff)
downloadgmp-07cf896c2f829c1dd6a5456aa7e710044a6e594a.tar.gz
* mpz/aors_ui.h: Renamed from mpz/aors_ui.c.
Diffstat (limited to 'mpz/aors_ui.h')
-rw-r--r--mpz/aors_ui.h99
1 files changed, 99 insertions, 0 deletions
diff --git a/mpz/aors_ui.h b/mpz/aors_ui.h
new file mode 100644
index 000000000..c4ed1bd00
--- /dev/null
+++ b/mpz/aors_ui.h
@@ -0,0 +1,99 @@
+/* mpz_add_ui, mpz_sub_ui -- Add or subtract an mpz_t and an unsigned
+ one-word integer.
+
+Copyright 1991, 1993, 1994, 1996, 1999, 2000, 2001 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 2.1 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; 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"
+
+
+#ifdef OPERATION_add_ui
+#define FUNCTION mpz_add_ui
+#define VARIATION_CMP >=
+#define VARIATION_NEG
+#define VARIATION_UNNEG -
+#endif
+
+#ifdef OPERATION_sub_ui
+#define FUNCTION mpz_sub_ui
+#define VARIATION_CMP <
+#define VARIATION_NEG -
+#define VARIATION_UNNEG
+#endif
+
+#ifndef FUNCTION
+Error, need OPERATION_add_ui or OPERATION_sub_ui
+#endif
+
+
+void
+FUNCTION (mpz_ptr w, mpz_srcptr u, unsigned long int v)
+{
+ mp_srcptr up;
+ mp_ptr wp;
+ mp_size_t usize, wsize;
+ mp_size_t abs_usize;
+
+ usize = u->_mp_size;
+ abs_usize = ABS (usize);
+
+ /* If not space for W (and possible carry), increase space. */
+ wsize = abs_usize + 1;
+ if (w->_mp_alloc < wsize)
+ _mpz_realloc (w, wsize);
+
+ /* These must be after realloc (U may be the same as W). */
+ up = u->_mp_d;
+ wp = w->_mp_d;
+
+ if (abs_usize == 0)
+ {
+ wp[0] = v;
+ w->_mp_size = VARIATION_NEG (v != 0);
+ return;
+ }
+
+ if (usize VARIATION_CMP 0)
+ {
+ mp_limb_t cy;
+ cy = mpn_add_1 (wp, up, abs_usize, (mp_limb_t) v);
+ wp[abs_usize] = cy;
+ wsize = VARIATION_NEG (abs_usize + cy);
+ }
+ else
+ {
+ /* The signs are different. Need exact comparison to determine
+ which operand to subtract from which. */
+ if (abs_usize == 1 && up[0] < v)
+ {
+ wp[0] = v - up[0];
+ wsize = VARIATION_NEG 1;
+ }
+ else
+ {
+ mpn_sub_1 (wp, up, abs_usize, (mp_limb_t) v);
+ /* Size can decrease with at most one limb. */
+ wsize = VARIATION_UNNEG (abs_usize - (wp[abs_usize - 1] == 0));
+ }
+ }
+
+ w->_mp_size = wsize;
+}