This was added with the goal to eventually replace the per
pass subgroup/ballot size options, but that won't work because
some backends don't have a fixed subgroup size across the compilation
process.
It was also mostly added to hack around mesa state tracker behavior,
and we have a better solution there now.
Reviewed-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
Reviewed-by: Emma Anholt <emma@anholt.net>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/37164>
The goal here is to generate addresses that are a right-shifted version
of the actual byte address and record the shift amount in the
offset_shift index. While we could just insert a ushr at the end of
deref chains, this will prevent the shift to be optimized away in many
cases. Instead, we try to extract the shift from the array strides and
struct offsets that make up the deref chain, and only insert a ushr when
absolutely necessary (i.e., for casts). This means we have to walk the
entire deref chain at once for accesses that support offset_shift and we
don't use the standard algorithm of replacing each deref one at a time.
To be able to legally right-shift casts, we use the alignment
information and never shift more than what the alignment could support.
It should also be noted that casts generally have two sources: something
provided by the driver (e.g., a Vulkan resource index) or a variable
pointer coming from a phi/bcsel. For the latter, the entire access chain
consists of multiple parts that are ended by either a phi/bcsel or an
access. Only the part the ends in an access is handled by this new
algorithm; the other parts are handled as usual. This is necessary
because we have no way to encode the offset shift or to even know how
much we would be able to shift without knowing how it is accessed.
This commit adds the general implementation for lowering accesses using
offset_shift and adds a compiler option for drivers to enable it for
SSBO accesses.
Signed-off-by: Job Noorman <jnoorman@igalia.com>
Reviewed-by: Emma Anholt <emma@anholt.net>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/35092>
glsl needs to plumb this from the backend. we should clean up
nir_lower_subgroups to use this later but I don't have time to churn everything
right now.
Signed-off-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
Reviewed-by: Marek Olšák <maraeo@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/36649>
The two backends (ir3, dxil) using the lowering have
info->fs.uses_sample_shading matching set when sample shading is used -- the VK
drivers pass the rasterization state flag into the compiler, while
freedreno and d3d12 have caps->force_persample_interp so the frontend
creates a shader variant with info->fs.uses_sample_shading set.
This means that we can drop the sample-id SHL/AND in the pixel-rate
shading case, which in turn means that drivers don't need to have a
load_sample_id() that doesn't trigger sample-rate shading (which Adreno
doesn't have).
Signed-off-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/36429>
this lets the backend implement bounded loads (i.e. robust SSBOs) in a way
that's more clever than a full branch. similar idea to
load_global_constant_bound which should eventually be merged into this.
Signed-off-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
Reviewed-by: Job Noorman <job@noorman.info>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/35720>
If nir_opt_vectorize_io isn't called, 16-bit IO is broken.
This is a workaround to keep RADV working and consume incorrect NIR
while other drivers consume correct NIR.
Hopefully this will be removed ASAP.
Reviewed-by: Timothy Arceri <tarceri@itsqueeze.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/35315>
This change relocates the fdot lowering from the generic NIR to the lima,
since lima is the only consumer of this particular lowering. This avoids
potential conflicts with the similar fdot lowering already present in
nir_lower_alu_width.
Signed-off-by: Christian Gmeiner <cgmeiner@igalia.com>
Reviewed-by: Erico Nunes <nunes.erico@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/34757>
If the optional flag is set, compaction groups TES inputs based on which
outputs they are used for:
- inputs generating only POS/CLIP outputs are first
- inputs generating both POS/CLIP and VAR outputs are next
- inputs generating only VAR outputs are last
shader-db with ACO:
143 shaders have -1.44% average decrease in code size.
There are fewer input loads and more of them are vec4 instead of vec1-3.
Reviewed-by: Timur Kristóf <timur.kristof@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/32262>