Alyssa Rosenzweig
8c36ecd4b1
This handles the usual case. 8-bit register access parallels 16-bit access, but with one major caveat: in 8-bit mode, only half of the register file is actually (directly) accessible as sources. In particular, for each 16-bit integer register (hrN), we can only index a *single* 8-bit integer (qrN), corresponding to the lower 8-bits. To get the upper 8-bits, it is required to do an explicit shift. For example, to add the bytes of a 16-bit integer hr0.x and get the result as an 8-bit qr0, you'd need to do something like: ilsr hr1.x, hr0.x, #8 iadd qr0.x, qr0.x, qr1.x This scheme diverges from 32-bit registers, in that both the upper and lower halves of a 32-bit register are individually accessible as a pair of half registers. For contrast, to add the lower and upper 16-bits of a 32-bit integer r0.x, you can just: iadd hr0.x, hr0.x, hr1.x Since hr1.x = upper 16-bit of r0.x. Signed-off-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
`Mesa <https://mesa3d.org>`_ - The 3D Graphics Library ====================================================== Source ------ This repository lives at https://gitlab.freedesktop.org/mesa/mesa. Other repositories are likely forks, and code found there is not supported. Build & install --------------- You can find more information in our documentation (`docs/install.html <https://mesa3d.org/install.html>`_), but the recommended way is to use Meson (`docs/meson.html <https://mesa3d.org/meson.html>`_): .. code-block:: sh $ mkdir build $ cd build $ meson .. $ sudo ninja install Support ------- Many Mesa devs hang on IRC; if you're not sure which channel is appropriate, you should ask your question on `Freenode's #dri-devel <irc://chat.freenode.net#dri-devel>`_, someone will redirect you if necessary. Remember that not everyone is in the same timezone as you, so it might take a while before someone qualified sees your question. To figure out who you're talking to, or which nick to ping for your question, check out `Who's Who on IRC <https://dri.freedesktop.org/wiki/WhosWho/>`_. The next best option is to ask your question in an email to the mailing lists: `mesa-dev\@lists.freedesktop.org <https://lists.freedesktop.org/mailman/listinfo/mesa-dev>`_ Bug reports ----------- If you think something isn't working properly, please file a bug report (`docs/bugs.html <https://mesa3d.org/bugs.html>`_). Contributing ------------ Contributions are welcome, and step-by-step instructions can be found in our documentation (`docs/submittingpatches.html <https://mesa3d.org/submittingpatches.html>`_). Note that Mesa uses email mailing-lists for patches submission, review and discussions.