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-rw-r--r--gmp/mpz/set_d.c117
1 files changed, 117 insertions, 0 deletions
diff --git a/gmp/mpz/set_d.c b/gmp/mpz/set_d.c
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+/* mpz_set_d(integer, val) -- Assign INTEGER with a double value VAL.
+
+Copyright 1995, 1996, 2000-2003, 2006 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 "config.h"
+
+#if HAVE_FLOAT_H
+#include <float.h> /* for DBL_MAX */
+#endif
+
+#include "gmp.h"
+#include "gmp-impl.h"
+
+
+/* We used to have a special case for d < MP_BASE_AS_DOUBLE, just casting
+ double -> limb. Unfortunately gcc 3.3 on powerpc970-apple-darwin6.8.5
+ got this wrong. (It assumed __fixunsdfdi returned its result in a single
+ 64-bit register, where instead that function followed the calling
+ conventions and gave the result in two parts r3 and r4.) Hence the use
+ of __gmp_extract_double in all cases. */
+
+void
+mpz_set_d (mpz_ptr r, double d)
+{
+ int negative;
+ mp_limb_t tp[LIMBS_PER_DOUBLE];
+ mp_ptr rp;
+ mp_size_t rn;
+
+ DOUBLE_NAN_INF_ACTION (d,
+ __gmp_invalid_operation (),
+ __gmp_invalid_operation ());
+
+ negative = d < 0;
+ d = ABS (d);
+
+ rn = __gmp_extract_double (tp, d);
+
+ if (ALLOC(r) < rn)
+ _mpz_realloc (r, rn);
+
+ if (rn <= 0)
+ rn = 0;
+
+ rp = PTR (r);
+
+ switch (rn)
+ {
+ default:
+ MPN_ZERO (rp, rn - LIMBS_PER_DOUBLE);
+ rp += rn - LIMBS_PER_DOUBLE;
+ /* fall through */
+#if LIMBS_PER_DOUBLE == 2
+ case 2:
+ rp[1] = tp[1], rp[0] = tp[0];
+ break;
+ case 1:
+ rp[0] = tp[1];
+ break;
+#endif
+#if LIMBS_PER_DOUBLE == 3
+ case 3:
+ rp[2] = tp[2], rp[1] = tp[1], rp[0] = tp[0];
+ break;
+ case 2:
+ rp[1] = tp[2], rp[0] = tp[1];
+ break;
+ case 1:
+ rp[0] = tp[2];
+ break;
+#endif
+#if LIMBS_PER_DOUBLE == 4
+ case 4:
+ rp[3] = tp[3], rp[2] = tp[2], rp[1] = tp[1], rp[0] = tp[0];
+ break;
+ case 3:
+ rp[2] = tp[3], rp[1] = tp[2], rp[0] = tp[1];
+ break;
+ case 2:
+ rp[1] = tp[3], rp[0] = tp[2];
+ break;
+ case 1:
+ rp[0] = tp[3];
+ break;
+#endif
+ case 0:
+ break;
+ }
+
+ SIZ(r) = negative ? -rn : rn;
+}