[PPL-devel] mpz_addmul_ui with ui = 1

[Vincent Lefevre]

On 2009-02-03 08:06:44 +0100, Paul Zimmermann wrote:
>        Dear Roberto,
> 
> > 	// FIXME(0.10.1): the test seems to speed up the GMP computation.
> > 	if (tableau_ij != 0) {
> > 	  scalar_value = tableau_ij * norm_factor[i];
> > 	  add_mul_assign(challenger_den, scalar_value, scalar_value);
> > 	}
> >
> > inline void
> > add_mul_assign(GMP_Integer& x, const GMP_Integer& y, const GMP_Integer& z) {
> >    mpz_addmul(x.get_mpz_t(), y.get_mpz_t(), z.get_mpz_t());
> > }
> 
> I'm ignorant about C++, but maybe the speedup you observe is due to the
> scalar_value = tableau_ij * norm_factor[i] instruction which is not done
> any more (which types have scalar_value, tableau_ij and norm_factor[i] ?),

But for the other test, there is no such assignment.

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Vincent Lefèvre <vincent at vinc17.org> - Web: <http://www.vinc17.org/>
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