diff options
Diffstat (limited to 'gnu/lib/libgmp/mpf/cmp_si.c')
-rw-r--r-- | gnu/lib/libgmp/mpf/cmp_si.c | 98 |
1 files changed, 98 insertions, 0 deletions
diff --git a/gnu/lib/libgmp/mpf/cmp_si.c b/gnu/lib/libgmp/mpf/cmp_si.c new file mode 100644 index 00000000000..01f970812c9 --- /dev/null +++ b/gnu/lib/libgmp/mpf/cmp_si.c @@ -0,0 +1,98 @@ +/* mpf_cmp_si -- Compare a float with a signed integer. + +Copyright (C) 1993, 1994, 1995 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 Library General Public License as published by +the Free Software Foundation; either version 2 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 Library General Public +License for more details. + +You should have received a copy of the GNU Library 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" + +int +#if __STDC__ +mpf_cmp_si (mpf_srcptr u, long int vslimb) +#else +mpf_cmp_si (u, vslimb) + mpf_srcptr u; + long int vslimb; +#endif +{ + mp_srcptr up; + mp_size_t usize; + mp_exp_t uexp; + int usign; + + uexp = u->_mp_exp; + usize = u->_mp_size; + + /* 1. Are the signs different? */ + if ((usize < 0) == (vslimb < 0)) /* don't use xor, type size may differ */ + { + /* U and V are both non-negative or both negative. */ + if (usize == 0) + /* vslimb >= 0 */ + return -(vslimb != 0); + if (vslimb == 0) + /* usize >= 0 */ + return usize != 0; + /* Fall out. */ + } + else + { + /* Either U or V is negative, but not both. */ + return usize >= 0 ? 1 : -1; + } + + /* U and V have the same sign and are both non-zero. */ + + usign = usize >= 0 ? 1 : -1; + + /* 2. Are the exponents different (V's exponent == 1)? */ + if (uexp > 1) + return usign; + if (uexp < 1) + return -usign; + + usize = ABS (usize); + vslimb = ABS (vslimb); + + up = u->_mp_d; + +#define STRICT_MPF_NORMALIZATION 0 +#if ! STRICT_MPF_NORMALIZATION + /* Ignore zeroes at the low end of U and V. */ + while (*up == 0) + { + up++; + usize--; + } +#endif + + /* 3. Now, if the number of limbs are different, we have a difference + since we have made sure the trailing limbs are not zero. */ + if (usize > 1) + return usign; + + /* 4. Compare the mantissas. */ + if (*up > vslimb) + return usign; + else if (*up < vslimb) + return -usign; + + /* Wow, we got zero even if we tried hard to avoid it. */ + return 0; +} |