Imported gcc-4.4.3

[msp430-gcc.git] / mpfr / get_z.c

diff --git a/mpfr/get_z.c b/mpfr/get_z.c
new file mode 100644 (file)
index 0000000..8616cff
--- /dev/null
+++ b/mpfr/get_z.c
@@ -0,0 +1,44 @@
+/* mpfr_get_z_exp -- get a multiple-precision integer from
+                     a floating-point number
+
+Copyright 2004, 2006, 2007, 2008, 2009 Free Software Foundation, Inc.
+Contributed by the Arenaire and Cacao projects, INRIA.
+
+This file is part of the GNU MPFR Library.
+
+The GNU MPFR 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 MPFR 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 MPFR Library; see the file COPYING.LIB.  If not, write to
+the Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston,
+MA 02110-1301, USA. */
+
+#include "mpfr-impl.h"
+
+void
+mpfr_get_z (mpz_ptr z, mpfr_srcptr f, mp_rnd_t rnd)
+{
+  mpfr_t r;
+  mp_exp_t exp = MPFR_EXP (f);
+
+  /* if exp <= 0, then |f|<1, thus |o(f)|<=1 */
+  MPFR_ASSERTD (MPFR_PREC_MIN == 2);
+  mpfr_init2 (r, (exp <= 0) ? MPFR_PREC_MIN : exp + 1);
+  mpfr_rint (r, f, rnd);
+  MPFR_ASSERTN (MPFR_IS_FP (r) );
+  exp = mpfr_get_z_exp (z, r);
+  /* FIXME: It seems that exp < 0 is always true */
+  if (exp >= 0)
+    mpz_mul_2exp (z, z, exp);
+  else
+    mpz_div_2exp (z, z, -exp);
+  mpfr_clear (r);
+}