This is actually a no-op on AMD, so we really don't want to lower it to
something more complicated. There may be a more efficient way to do
this on Intel too. In addition, in the future we'll want to use this for
lowering boolean reduce operations, where the inverse ballot will
operate on the backend's "natural" ballot type as indicated by
options->ballot_bit_size, instead of uvec4 as produced by SPIR-V. In
total, there are now three possible lowerings we may have to perform:
- inverse_ballot with source type of uvec4 from SPIR-V to inverse_ballot
with natural source type, when the backend supports inverse_ballot
natively.
- inverse_ballot with source type of uvec4 from SPIR-V to arithmetic,
when the backend doesn't support inverse_ballot.
- inverse_ballot with natural source type from reduce operation, when
the backend doesn't support inverse_ballot.
Previously we just did the second lowering unconditionally in vtn, but
it's just a combination of the first and third. We add support here for
the first and third lowerings in nir_lower_subgroups, instead of simply
moving the second lowering, to avoid unnecessary churn.
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/25123>
Since using nir_shader_lower_instructions(), instructions get revisited
before proceeding with the next one. This already guarantees that any
subsequent lowerings of those instructions happen during the same pass
of nir_lower_subgroups().
v2: use nir_shader_lower_instructions() instead of setting the cursor.
Co-authored-by: Daniel Schürmann <daniel@schuermann.dev>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/25123>
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>
Since 624e799cc3 ("nir: Drop nir_ssa_def::name and nir_register::name"), SSA
defs don't have names, making the name argument unused. Drop it from the
signature and fix the call sites. This was done with the help of the following
Coccinelle semantic patch:
@@
expression A, B, C, D, E;
@@
-nir_ssa_dest_init(A, B, C, D, E);
+nir_ssa_dest_init(A, B, C, D);
Signed-off-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
Reviewed-by: Timur Kristóf <timur.kristof@gmail.com>
Reviewed-by: Emma Anholt <emma@anholt.net>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/23078>
This is almost always a nir_instr and updating the src of a nir_if will
have to work slightly differently in the future.
Signed-off-by: Rhys Perry <pendingchaos02@gmail.com>
Acked-by: Alyssa Rosenzweig <alyssa@collabora.com>
Reviewed-by: Jason Ekstrand <jason.ekstrand@collabora.com>
Reviewed-by: Emma Anholt <emma@anholt.net>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/12910>
Signed-off-by: Konstantin Seurer <konstantin.seurer@gmail.com>
Reviewed-By: Mike Blumenkrantz <michael.blumenkrantz@gmail.com>
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
Reviewed-by: Jason Ekstrand <jason.ekstrand@collabora.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/17242>
This pattern pops up a bunch and the semantics of nir_channels() aren't
very convenient much of the time. Let's add a nir_trim_vector() which
matches nir_pad_vector().
Reviewed-by: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/16309>
The BITFIELD_MASK() macro is intended for using with actual bitfields,
not with nir_component_mask_t. This means we do some extra work to
handle values that are invalid for nir_component_mask_t in the first
place.
This eliminates some warnings on Clang, where the compiler complains
about casting UINT32_MAX to UINT16_MAX.
Reviewed-by: Alyssa Rosenzweig <alyssa@collabora.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/15547>
Qualcomm doesn't natively support shuffle, but it does natively support
relative shuffles where the delta is a constant. Therefore we'll expose
emulated support for both. Add support for this emulation of
subgroupShuffle() to NIR.
Reviewed-by: Daniel Schürmann <daniel@schuermann.dev>
Reviewed-by: Danylo Piliaiev <dpiliaiev@igalia.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/14412>
This option only applies to relative shuffles (up/down/xor), and in a
moment we're going to add an option to lower normal shuffles, so rename
it.
While we're here, rename lower_shuffle() to lower_to_shuffle() for
similar reasons.
Reviewed-by: Danylo Piliaiev <dpiliaiev@igalia.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/14412>
This is required for Zink where the API ballot type is a uint64_t and
the "hardware" ballot type is uvec4.
Reviewed-By: Mike Blumenkrantz <michael.blumenkrantz@gmail.com>
Reviewed-by: Connor Abbott <cwabbott0@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/11989>
On qualcomm, we have shared registers similar to SGPR's on AMD. However,
there is no readlane or readfirstlane primitive. shared registers can
only be written to when just one lane is active. This means that we have
to lower readInvocation(val, id) to something like:
if (gl_SubgroupInvocation == id) {
scalar_reg = val;
}
return scalar_reg;
However it's a bit difficult to actually get the value of
gl_SubgroupInvocation in the backend, because for compute it requires
some calculations and we don't have any CSE support in the backend. This
intrinsic lets us turn it into
"readInvocationCond(val, id == gl_SubgroupInvocation)" in NIR at which
point the backend code generation is a lot easier.
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/6752>
Qualcomm has a mode with a subgroup size of 128, so just emitting larger
integer operations and then lowering them later isn't an option. This
makes the pass able to handle the lowering itself, so that we don't have
to go down to 64-thread wavefronts when ballots are used.
(The GLSL and legacy SPIR-V extensions only support a maximum of 64
threads, but I guess we'll cross that bridge when we come to it...)
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/6752>
Lower it to a vote instead of a ballot. This was only used for AMD, and
in that case they're pretty much the same. However Qualcomm has a vote
builtin, which we want to use instead of ballots.
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
Acked-by: Rhys Perry <pendingchaos02@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/6752>
A couple of these probably aren't strictly necessary but they won't
hurt. The one that's particularly tricky is a fixed-length array in
nir_search.h. However, to avoid blowing up the binary size of
nir_opt_algebraic by about 2x, we just assert that only small ops are
used.
Cc: mesa-stable@lists.freedesktop.org
Reviewed-by: Jesse Natalie <jenatali@microsoft.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/6655>
Thanks to VK_EXT_subgroup_size_control, we can end up with
gl_SubgroupSize being as low as 8 on Intel.
Fixes: d10de25309 "anv: Implement VK_EXT_subgroup_size_control"
Reviewed-by: Caio Marcelo de Oliveira Filho <caio.oliveira@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/4694>
Some hardware doesn't support subgroup shuffle, and on such hardware
it makes no sense to lower quad broadcasts to shuffle. Instead, let's
lower them to four const quad broadcasts, paired with bcsel instructions.
Cc: mesa-stable@lists.freedesktop.org
Signed-off-by: Timur Kristóf <timur.kristof@gmail.com>
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
Reviewed-by: Samuel Pitoiset <samuel.pitoiset@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/4147>
This is required for the subgroupBroadcastDynamicId feature that was
added in Vulkan 1.2.
Reviewed-by: Caio Marcelo de Oliveira Filho <caio.oliveira@intel.com>
Instead of building a constant mask (which depends on knowing the
subgroup size), we build an expression. Because the pass uses the
nir_shader_lower_instructions helper, subgroup lowering will be run on
any newly emitted instructions as well as the previously existing
instructions. In particular, if the subgroup size is known, the newly
emitted subgroup_size intrinsic will get turned into a constant and a
later constant folding pass will clean it up.
Reviewed-by: Caio Marcelo de Oliveira Filho <caio.oliveira@intel.com>
This is based heavily on 97f10934ed, "ac/nir: Add vote_ieq/vote_feq
lowering pass." from Bas Nieuwenhuizen. This version is a bit more
general since it's in common code. It also properly handles NaN due to
not flipping the comparison for floats.
Reviewed-by: Bas Nieuwenhuizen <bas@basnieuwenhuizen.nl>
