summaryrefslogtreecommitdiff
path: root/Build/source/libs/gmp/gmp-6.0.0/mpf/get_si.c
diff options
context:
space:
mode:
Diffstat (limited to 'Build/source/libs/gmp/gmp-6.0.0/mpf/get_si.c')
-rw-r--r--Build/source/libs/gmp/gmp-6.0.0/mpf/get_si.c87
1 files changed, 87 insertions, 0 deletions
diff --git a/Build/source/libs/gmp/gmp-6.0.0/mpf/get_si.c b/Build/source/libs/gmp/gmp-6.0.0/mpf/get_si.c
new file mode 100644
index 00000000000..5b63dbd4256
--- /dev/null
+++ b/Build/source/libs/gmp/gmp-6.0.0/mpf/get_si.c
@@ -0,0 +1,87 @@
+/* mpf_get_si -- mpf to long conversion
+
+Copyright 2001, 2002, 2004 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"
+
+
+/* Any fraction bits are truncated, meaning simply discarded.
+
+ For values bigger than a long, the low bits are returned, like
+ mpz_get_si, but this isn't documented.
+
+ Notice this is equivalent to mpz_set_f + mpz_get_si.
+
+
+ Implementation:
+
+ fl is established in basically the same way as for mpf_get_ui, see that
+ code for explanations of the conditions.
+
+ However unlike mpf_get_ui we need an explicit return 0 for exp<=0. When
+ f is a negative fraction (ie. size<0 and exp<=0) we can't let fl==0 go
+ through to the zany final "~ ((fl - 1) & LONG_MAX)", that would give
+ -0x80000000 instead of the desired 0. */
+
+long
+mpf_get_si (mpf_srcptr f) __GMP_NOTHROW
+{
+ mp_exp_t exp;
+ mp_size_t size, abs_size;
+ mp_srcptr fp;
+ mp_limb_t fl;
+
+ exp = EXP (f);
+ size = SIZ (f);
+ fp = PTR (f);
+
+ /* fraction alone truncates to zero
+ this also covers zero, since we have exp==0 for zero */
+ if (exp <= 0)
+ return 0L;
+
+ /* there are some limbs above the radix point */
+
+ fl = 0;
+ abs_size = ABS (size);
+ if (abs_size >= exp)
+ fl = fp[abs_size-exp];
+
+#if BITS_PER_ULONG > GMP_NUMB_BITS
+ if (exp > 1 && abs_size+1 >= exp)
+ fl |= fp[abs_size - exp + 1] << GMP_NUMB_BITS;
+#endif
+
+ if (size > 0)
+ return fl & LONG_MAX;
+ else
+ /* this form necessary to correctly handle -0x80..00 */
+ return -1 - (long) ((fl - 1) & LONG_MAX);
+}