[PPL-devel] mpz_addmul_ui with ui = 1

[Vincent Lefevre]

On 2009-02-02 18:37:08 -0600, Gabriel Dos Reis wrote:
> On Mon, Feb 2, 2009 at 6:08 PM, Vincent Lefevre <vincent at vinc17.org> wrote:
> > On 2009-02-02 22:30:03 +0100, Roberto Bagnara wrote:
> >> #if 1 // CHECKME: the test seems to speed up the GMP computation.
> >>       const Coefficient& y_i = y[i];
> >>       if (y_i != 0)
> >>       sub_mul_assign(x_i, y_i, normalized_x_k);
> >> #else
> >>       sub_mul_assign(x_i, y[i], normalized_x_k);
> >> #endif // 1
> >
> > Couldn't this be due to C++ overhead? Have you tried in C?
> 
> That would be surprising.

Yes, but can anyone guess any non-surprising reason? :)

BTW, Roberto, are you sure that the speed-up is due to the test itself
and not an arbitrary side effect because the code has just changed?

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