fenics team mailing list archive

[Martin Sandve Alnæs <martinal@xxxxxxxxx>]

For the uflacs backend, lets just say it's experimental for now. Selecting
representation "uflacs" in ffc should work for forms with only cell
integrals, "non-fancy" elements, only first order derivatives, and no cell
volume and such. Preliminary informal benchmarking shows that basic
hyperelasticity compiles in 1/13 of the time as the old optimized
quadrature representation with comparable runtime performance. More
features are on the way and more benchmarks will be presented at the FEniCS
2013 workshop.

Martin


On 4 March 2013 17:26, Anders Logg <logg@xxxxxxxxx> wrote:

> The ufc-geometry branches of UFC, FFC and DOLFIN have been merged into
> trunk. In addition, the FFC branch merges in Martin's addition of the
> new uflacs compiler backend to FFC. (Martin can comment on the status
> of the uflacs backend.)
>
> The changes in ufc-geometry were motivated by a cleanup of the
> codesnippets in FFC and a simplification (?) of the UFC interface.
> Some changes:
>
> - Introduce header ufc_geometry.h in UFC to replace codesnippets.
>   Quite a few codesnippets remain and should be migrated to the same
>   header file.
>
> - Use flattened arrays for all data structures. See comment on top of
>   ufc_geometry.h for some remarks on the efficiency vs nested arrays
>   and flattened/nested std::vector.
>
> - Remove ufc::cell as a common data structure holding a bunch of data
>   that may not be needed and therefore should not need to be updated.
>   Instead, all data should be passed by primitive C data types.
>
> Some of these are work in progress and more work needs to be
> done. Before this, I'm going to merge UFC into FFC (if there are no
> objections) to simplify the continued work as it involves changes on
> both ends.
>
> All tests in FFC and DOLFIN pass, but since quite a few things needed
> to be changed (including some tedious and error-prone translation of
> nested arrays for Jacobians and such into flattened arrays) there may
> be bugs so watch out...
>
> --
> Anders
>
>
> _______________________________________________
> Mailing list: https://launchpad.net/~fenics
> Post to     : fenics@xxxxxxxxxxxxxxxxxxx
> Unsubscribe : https://launchpad.net/~fenics
> More help   : https://help.launchpad.net/ListHelp
>