diff options
Diffstat (limited to 'mpq/inv.c')
| -rw-r--r-- | mpq/inv.c | 35 |
1 files changed, 15 insertions, 20 deletions
@@ -1,7 +1,7 @@ /* mpq_inv(dest,src) -- invert a rational number, i.e. set DEST to SRC with the numerator and denominator swapped. -Copyright 1991, 1994, 1995, 2000, 2001 Free Software Foundation, Inc. +Copyright 1991, 1994, 1995, 2000, 2001, 2012 Free Software Foundation, Inc. This file is part of the GNU MP Library. @@ -22,44 +22,39 @@ along with the GNU MP Library. If not, see http://www.gnu.org/licenses/. */ #include "gmp-impl.h" void -mpq_inv (MP_RAT *dest, const MP_RAT *src) +mpq_inv (mpq_ptr dest, mpq_srcptr src) { mp_size_t num_size = SIZ(NUM(src)); mp_size_t den_size = SIZ(DEN(src)); - if (UNLIKELY (num_size == 0)) - DIVIDE_BY_ZERO; - if (num_size < 0) { num_size = -num_size; den_size = -den_size; } + else if (UNLIKELY (num_size == 0)) + DIVIDE_BY_ZERO; + SIZ(DEN(dest)) = num_size; SIZ(NUM(dest)) = den_size; - /* If dest == src we may just swap the numerator and denominator, but - we have to ensure the new denominator is positive. */ + /* If dest == src we may just swap the numerator and denominator; + we ensured that the new denominator is positive. */ if (dest == src) { - mp_size_t alloc = ALLOC(NUM(dest)); - mp_ptr limb_ptr = PTR(NUM(dest)); - - ALLOC(NUM(dest)) = ALLOC(DEN(dest)); - PTR(NUM(dest)) = PTR(DEN(dest)); - - ALLOC(DEN(dest)) = alloc; - PTR(DEN(dest)) = limb_ptr; + MP_PTR_SWAP (PTR(NUM(dest)), PTR(DEN(dest))); + MP_SIZE_T_SWAP (ALLOC(NUM(dest)), ALLOC(DEN(dest))); } else { - den_size = ABS (den_size); + mp_ptr dp; - MPZ_REALLOC (NUM(dest), den_size); - MPZ_REALLOC (DEN(dest), num_size); + den_size = ABS (den_size); + dp = MPZ_REALLOC (NUM(dest), den_size); + MPN_COPY (dp, PTR(DEN(src)), den_size); - MPN_COPY (PTR(NUM(dest)), PTR(DEN(src)), den_size); - MPN_COPY (PTR(DEN(dest)), PTR(NUM(src)), num_size); + dp = MPZ_REALLOC (DEN(dest), num_size); + MPN_COPY (dp, PTR(NUM(src)), num_size); } } |