remove extra division in mpq/aors.c

[Marc Glisse]

On Sun, 20 Feb 2011, Torbjorn Granlund wrote:

> Marc Glisse <marc.glisse at inria.fr> writes:
>
>  the file doc/tasks.html mentions an extra division in
>  mpq/aors.c. Would something like the attached do?
>
> I find it very, very difficult to understand unidiffs.  Please use
> context diffs for GMP patches.

Ok, I'll try to remember that. See attached.

> I suppose we should at some point perform bdiv-type
> precomputations on the 'gcd' value.

That's precisely the item written next to this one in the tasks file ;-)
But it is more complicated, so I won't do it myself.

> For making hg generate context diffs (hg cdiff), put this in your
> ~/.hgrc:
>
> [extensions]
> hgext.extdiff=
>
> [extdiff]
> cmd.cdiff = diff
> opts.cdiff = -Nrc2

Can this be done on a project basis? Other projects specifically ask for 
unified diffs...

-- 
Marc Glisse
-------------- next part --------------
*** /data/repos/gmp/mpq/aors.c	2011-02-19 18:32:22.753357195 +0100
--- mpq/aors.c	2011-02-20 17:07:25.106236000 +0100
***************
*** 53,67 ****
        mpz_t t;
  
        mpz_divexact_gcd (tmp1, &(op2->_mp_den), gcd);
        mpz_mul (tmp1, &(op1->_mp_num), tmp1);
  
!       mpz_divexact_gcd (tmp2, &(op1->_mp_den), gcd);
!       mpz_mul (tmp2, &(op2->_mp_num), tmp2);
  
!       MPZ_TMP_INIT (t, MAX (ABS (tmp1->_mp_size), ABS (tmp2->_mp_size)) + 1);
  
!       (*fun) (t, tmp1, tmp2);
!       mpz_divexact_gcd (tmp2, &(op1->_mp_den), gcd);
  
        mpz_gcd (gcd, t, gcd);
        if (MPZ_EQUAL_1_P (gcd))
--- 53,68 ----
        mpz_t t;
  
        mpz_divexact_gcd (tmp1, &(op2->_mp_den), gcd);
+       mpz_divexact_gcd (tmp2, &(op1->_mp_den), gcd);
+ 
        mpz_mul (tmp1, &(op1->_mp_num), tmp1);
  
!       MPZ_TMP_INIT (t, 1 + MAX (ABS (tmp1->_mp_size),
!                                 op2_num_size + ABS (tmp2->_mp_size)));
  
!       mpz_mul (t, &(op2->_mp_num), tmp2);
  
!       (*fun) (t, tmp1, t);
  
        mpz_gcd (gcd, t, gcd);
        if (MPZ_EQUAL_1_P (gcd))
-------------- next part --------------
*** /data/repos/gmp/mpq/aors.c	2011-02-19 18:32:22.753357195 +0100
--- mpq/aors.c	2011-02-20 17:11:07.248427000 +0100
***************
*** 52,67 ****
      {
        mpz_t t;
  
!       mpz_divexact_gcd (tmp1, &(op2->_mp_den), gcd);
!       mpz_mul (tmp1, &(op1->_mp_num), tmp1);
  
        mpz_divexact_gcd (tmp2, &(op1->_mp_den), gcd);
-       mpz_mul (tmp2, &(op2->_mp_num), tmp2);
  
!       MPZ_TMP_INIT (t, MAX (ABS (tmp1->_mp_size), ABS (tmp2->_mp_size)) + 1);
  
!       (*fun) (t, tmp1, tmp2);
!       mpz_divexact_gcd (tmp2, &(op1->_mp_den), gcd);
  
        mpz_gcd (gcd, t, gcd);
        if (MPZ_EQUAL_1_P (gcd))
--- 52,67 ----
      {
        mpz_t t;
  
!       MPZ_TMP_INIT (t, MAX (op1_num_size + op2_den_size,
! 	     op2_num_size + op1_den_size) + 2 - gcd->_mp_size);
  
+       mpz_divexact_gcd (t, &(op2->_mp_den), gcd);
        mpz_divexact_gcd (tmp2, &(op1->_mp_den), gcd);
  
!       mpz_mul (tmp1, &(op1->_mp_num), t);
!       mpz_mul (t, &(op2->_mp_num), tmp2);
  
!       (*fun) (t, tmp1, t);
  
        mpz_gcd (gcd, t, gcd);
        if (MPZ_EQUAL_1_P (gcd))