Geometry and tessellation shaders process multiple vertices; their
inputs are arrays indexed by the vertex number. While GLSL makes
this look like a normal array, it can be very different behind the
scenes.
On Intel hardware, all inputs for a particular vertex are stored
together - as if they were grouped into a single struct. This means
that consecutive elements of these top-level arrays are not contiguous.
In fact, they may sometimes be in completely disjoint memory segments.
NIR's existing load_input intrinsics are awkward for this case, as they
distill everything down to a single offset. We'd much rather keep the
vertex ID separate, but build up an offset as normal beyond that.
This patch introduces new nir_intrinsic_load_per_vertex_input
intrinsics to handle this case. They work like ordinary load_input
intrinsics, but have an extra source (src[0]) which represents the
outermost array index.
v2: Rebase on earlier refactors.
v3: Use ssa defs instead of nir_srcs, rebase on earlier refactors.
Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Jason Ekstrand <jason.ekstrand@intel.com>
At least on Intel hardware, gl_PrimitiveIDIn comes in as a special part
of the payload rather than a normal input. This is typically what we
use system values for. Dave and Ilia also agree that a system value
would be nicer.
At some point, we should change it at the GLSL IR level as well. But
that requires changing most of the drivers. For now, let's at least
make NIR do the right thing, which is easy.
v2: Add a comment about not creating a temporary (suggested by Iago).
Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Iago Toral Quiroga <itoral@igalia.com>
The original GLSL IR intrinsics have been lowered to an internal
version that accepts a block index and an offset instead of a
SSBO reference.
v2 (Connor):
- Document the sources used by the atomic intrinsics.
Reviewed-by: Connor Abbott <connor.w.abbott@intel.com>
Reviewed-by: Kristian Høgsberg <krh@bitplanet.net>
v2 (Connor):
- Make the STORE() macro take arguments for the extra sources (and their
size) and any extra indices required.
Reviewed-by: Kristian Høgsberg <krh@bitplanet.net>
This is how backends provide the buffer size required to compute
the size of unsized arrays in the previous patch
Signed-off-by: Samuel Iglesias Gonsalvez <siglesias@igalia.com>
Reviewed-by: Kristian Høgsberg <krh@bitplanet.net>
This patch also introduces a lowering pass to convert the simple GS
intrinsics to the new ones. See the comments above that for the
rationale behind the new intrinsics.
This should be useful for i965; it's a generic enough mechanism that I
could see other drivers potentially using it as well, so I don't feel
too bad about putting it in the generic code.
v2:
- Use nir_after_block_before_jump for the cursor (caught by Jason
Ekstrand - I'd mistakenly used nir_after_block when rebasing this
code onto the new NIR control flow API).
- Remove the old emit_vertex intrinsic at the end, rather than in
the middle (requested by Jason).
- Use state->... directly rather than locals (requested by Jason).
- Report progress from nir_lower_gs_intrinsics() (requested by me).
- Remove "Authors:" section from file comment (requested by
Michael Schellenberger Costa).
Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Jason Ekstrand <jason.ekstrand@intel.com>
For lowering user-clip-planes, we need a way to pass the enabled/used
user-clip-planes in to shader.
Signed-off-by: Rob Clark <robclark@freedesktop.org>
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
In the i965 backend, we want to be able to "pull apart" the uniforms and
push some of them into the shader through a different path. In order to do
this effectively, we need to know which variable is actually being referred
to by a given uniform load. Previously, it was completely flattened by
nir_lower_io which made things difficult. This adds more information to
the intrinsic to make this easier for us.
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
v2, review from Francisco Jerez:
- make the destination variable as large as what the nir instrinsic
defines (4) instead of the size of the return variable of glsl. This
is still safe for the already existing code because all the intrinsics
affected returned the same amount of components as expected by glsl IR.
In the case of image_size, it is not possible to do so because the
returned number of component depends on the image type and this case
is not well handled by nir.
v3:
- Style fix
Signed-off-by: Martin Peres <martin.peres@linux.intel.com>
Reviewed-by: Francisco Jerez <currojerez@riseup.net>
The GLSL layer above is still hacky, so we're really just moving the
hack into GLSL-to-NIR. I'd rather not go all the way and make GLSL
support the Vulkan binding model too, since presumably we'll be
switching to SPIR-V exclusively, and so working on proper GLSL support
will be a waste of time. For now, doing this keeps it working as we add
SPIR-V->NIR support though.
Previously, we used intrinsic->const_index[1] to represent "the number of
array elements to load" for load/store intrinsics. However, this set to 1
by every pass that ever creates a load/store intrinsic. Also, while it
might make some sense for registers, it makes no sense whatsoever in SSA.
On top of that, the i965 backend was the only backend to ever support it;
freedreno and vc4 just assert that it's always 1. Let's just delete it.
Signed-off-by: Jason Ekstrand <jason.ekstrand@intel.com>
Reviewed-by: Connor Abbott <cwabbott0@gmail.com>
Reviewed-by: Rob Clark <robclark@freedesktop.org>
Ian and I added these around the time Connor was developing NIR. Now
that both exist, we should make them work together!
Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
Reviewed-by: Jason Ekstrand <jason.ekstrand@intel.com>
This is a conditional discard, which takes a boolean source.
Note that we don't generate ir_discard::condition today, so this
shouldn't break drivers (since none implement this intrinsic yet).
Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Connor Abbott <cwabbott0@gmail.com>
Reviewed-by: Matt Turner <mattst88@gmail.com>
Reviewed-by: Eric Anholt <eric@anholt.net>
In GLSL-to-NIR we were just setting the base index to 0 whenever there was
an indirect so having it expressed as a sum makes no sense. Also, while a
base offset may make sense for the memory location (first element in the
array, etc.) it makes less sense for the actual uniform buffer index. This
may change later, but it seems to make more sense for now.
Reviewed-by: Connor Abbott <cwabbott0@gmail.com>
We used to have the number of components built into the intrinsic. This
meant that all of our load/store intrinsics had vec1, vec2, vec3, and vec4
variants. This lead to piles of switch statements to generate the correct
intrinsic names, and introspection to figure out the number of components.
We can make things much nicer by allowing "vectorized" intrinsics.
Reviewed-by: Connor Abbott <cwabbott0@gmail.com>
This includes all the instructions, ifs, loops, functions, etc. This is
similar to the information in ir.h.
v2: Jason Ekstrand <jason.ekstrand@intel.com>:
Include ralloc and hash_table from the util directory
whitespace fixes
Signed-off-by: Jason Ekstrand <jason.ekstrand@intel.com>
Reviewed-by: Eric Anholt <eric@anholt.net>
Reviewed-By glenn.kennard <glenn.kennard@gmail.com>
