In geometry shaders, calling EmitVertex() makes the contents of all
output variables undefined. We need to rewrite our layer ID and view
index outputs before each EmitVertex() call; assuming they'll preserve
their values is undefined behavior.
Reviewed-by: Caio Oliveira <caio.oliveira@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/28067>
Currently, build_view_index and build_instance_id emit load_instance_id
intrinsics, which want the instance ID coming into the program, which is
the true instance ID multiplied by the view count.
The loop also remaps any load_instance_id in the original program back
to the true instance ID, which is the one coming in divided by the view
count. Because we call build_view_index and build_instance_id as part
of the loop, and emit the new load_instance_id instructions earlier in
the shader, we successfully avoid seeing those.
However, this is a bit fragile as it means you can't call
build_view_index or build_instance_id prior to the loop without
accidentally remapping things we don't intend to. To fix this
fragility, we save off the original instance ID (including the view
count) and directly reference that.
Reviewed-by: Caio Oliveira <caio.oliveira@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/28067>
Instead, we replace every use of it with nir_def. Most of this commit
was generated by sed:
sed -i -e 's/dest.ssa/def/g' src/**/*.h src/**/*.c src/**/*.cpp
A few manual fixups were required in lima and the nir_legacy code.
Acked-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/24674>
Now that we're using nir_intrinsic_load_layer_id for ViewIndex, we can
use primitive replication even when the FS uses ViewIndex. Also, only
check that active_stages doesn't contain anything other than VS and FS,
not that it's exactly VS | FS. This both decouples things more and
allows primitive rplication in the depth-only case where we have no
fragment shader at all.
Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Reviewed-by: Caio Oliveira <caio.oliveira@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/17602>
This is about the only "small" change we can make in the process of
converting from render-pass-based to dynamic-rendering-based. Make
everything in pipeline creation work in terms of dynamic rendering and
create the dynamic rendering structs from the render pass as-needed.
Reviewed-by: Ivan Briano <ivan.briano@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/14961>
Identify if view_index is used only for position calculation, and use
Primitive Replication to implement Multiview in Gen12. This feature
allows storing per-view position information in a single execution of
the shader, treating position as an array.
The shader is transformed by adding a for-loop around it, that have an
iteration per active view (in the view_mask). Stores to the position
now store into the position array for the current index in the loop,
and load_view_index() will return the view index corresponding to the
current index in the loop.
The feature is controlled by setting the environment variable
ANV_PRIMITIVE_REPLICATION_MAX_VIEWS, which defaults to 2 if unset.
For pipelines with view counts larger than that, the regular
instancing will be used instead of Primitive Replication. To disable
it completely set the variable to 0.
v2: Don't assume position is set in vertex shader; remove only stores
for position; don't apply optimizations since other passes will
do; clone shader body without extract/reinsert; don't use
last_block (potentially stale). (Jason)
Fix view_index immediate to contain the view index, not its order.
Check for maximum number of views supported.
Add guard for gen12.
v3: Clone the entire shader function and change it before reinsert;
disable optimization when shader has memory writes. (Jason)
Use a single environment variable with _DEBUG on the name.
v4: Change to use new nir_deref_instr.
When removing stores, look for mode nir_var_shader_out instead
of the walking the list of outputs.
Ensure unused derefs are removed in the non-position part of the
shader.
Remove dead control flow when identifying if can use or not
primitive replication.
v5: Consider all the active shaders (including fragment) when deciding
that Primitive Replication can be used.
Change environment variable to ANV_PRIMITIVE_REPLICATION.
Squash the emission of 3DSTATE_PRIMITIVE_REPLICATION into this patch.
Disable Prim Rep in blorp_exec_3d.
v6: Use a loop around the shader, instead of manually unrolling, since
the regular unroll pass will kick in.
Document that we don't expect to see copy_deref or load_deref
involving the position variable.
Recover use_primitive_replication value when loading pipeline from
the cache.
Set VARYING_SLOT_LAYER to 0 in the shader. Earlier versions were
relying on ForceZeroRTAIndexEnable but that might not be
sufficient.
Disable Prim Rep in cmd_buffer_so_memcpy.
v7: Don't use Primitive Replication if position is not set, fallback
to instancing; change environment variable to be
ANV_PRIMITVE_REPLICATION_MAX_VIEWS and default it to 2 based on
experiments.
Reviewed-by: Rafael Antognolli <rafael.antognolli@intel.com>
Tested-by: Marge Bot <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/2313>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/2313>
Unlike most of the cases in which we do this by hand, the new helper
properly handles non-32-bit pointers.
Reviewed-by: Karol Herbst <kherbst@redhat.com>
Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
SPIR-V allows for matrix and array types to be decorated with explicit
byte stride decorations and matrix types to be decorated row- or
column-major. This commit adds support to glsl_type to encode this
information. Because this doesn't work nicely with std430 and std140
alignments, we add asserts to ensure that we don't use any of the std430
or std140 layout functions with explicitly laid out types.
In SPIR-V, the layout information for matrices is applied to the parent
struct member instead of to the matrix type itself. However, this is
gets rather clumsy when you're walking derefs trying to compute offsets
because, the moment you hit a matrix, you have to crawl back the deref
chain and find the struct. Instead, we take the same path here as we've
taken in spirv_to_nir and put the decorations on the matrix type itself.
This also subtly adds support for strided vector types. These don't
come up in SPIR-V directly but you can get one as the result of taking a
column from a row-major matrix or a row from a column-major matrix.
Reviewed-by: Alejandro Piñeiro <apinheiro@igalia.com>
and _mesa_bitcount_64 with util_bitcount_64. This fixes a build problem
in nir for platforms that don't have popcount or popcountll, such as
32bit msvc.
v2: - Fix additional uses of _mesa_bitcount added after this was
originally written
Acked-by: Eric Engestrom <eric.engestrom@intel.com> (v1)
Acked-by: Eric Anholt <eric@anholt.net>
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
The new name make the zero-input behavior more obvious. The next
patch adds a new function with different zero-input behavior.
Signed-off-by: Ian Romanick <ian.d.romanick@intel.com>
Suggested-by: Matt Turner <mattst88@gmail.com>
Reviewed-by: Alejandro Piñeiro <apinheiro@igalia.com>
If view mask has only one bit set, view index is effectively a
constant, so doesn't need to be passed to the next stages, just always
set it.
Part of this was in the original patch that added
anv_nir_lower_multiview.c but disabled.
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
The view_index is encoded in the remainder of dividing instance id by
the number of views in the view mask (n). In the general case (handled
by the else clause), there is a need to map from 0..n-1 into the
number of the view being masked. For that a map is encoded.
In the case only the first n bits in the mask are set, the mapping is
trivial, 0..n-1 already represent what view is being referred to.
That case was in the original patch that added
anv_nir_lower_multiview.c but disabled.
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
v2 (Jason Ekstrand):
- Take a view_mask rather than a whole subpass
- Build the view mask into the VS shader key
Reviewed-by: Iago Toral Quiroga <itoral@igalia.com>
