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>
This is kept as a separate commit because the change looks like a lot
more than it it. The order of the two loops is swapped, then the two
loops are merged.
Suggested-by: Kenneth Graunke <kenneth@whitecape.org>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/25091>
Using a single data structure seems better. There's no appreciable
performance change. On batman_arkham_city_goty.foz, the difference
reported was 0.48%±0.36% (n=20). Several commits in the MR, including
some that should have no effect at all, reported similar changes. I
attribute this primarily changing of loop alignments and similar.
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/25091>
On batman_arkham_city_goty.foz, this improves fossil-db time by
-3.83%±0.24% (n=20). This fossil takes the longest time of any in my
database.
v2: Add some comments for cmp_entry_src_entry_src and
cmp_entry_src_nr. Suggested by Ken.
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/25091>
This annoyed me durning development of this MR. Every time I changed the
parameters to this internal function, I had to modify a public header
file... and trigger a much large rebuild.
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/25091>
The larger predicate here already requires that inst->opcode must be
BRW_OPCODE_MOV, so it can't BRW_OPCODE_SEL. With that removed, the
other simplifications are pretty straight forward.
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/25091>
The caller already loops over the sources. This means that the caller
must loop over the sources in reverse because constant propagation
prefers to propagate into the last sources first.
The shader-db and fossil-db changes (below) are all due to SEL
instructions. Changing the order sources are visited changes whether a
SEL with two immediate sources is
(+f0.0) sel g12 IMM_A IMM_B
or
(-f0.0) sel g12 IMM_B IMM_A
The ordering of the sources affects the order the constant combining
encounters the values, and the determines which value is "combined"
and which value remains an immediate.
This affects the results by luck. If there are two instructions:
(+f0.0) sel g12 IMM_A IMM_B
(+f0.0) sel g13 IMM_A IMM_C
Picking IMM_A is advantageous over picking IMM_B and IMM_C. Since the
selection algorithm in constant combining is greedy, this case
requires the algorithm see the values in just the right order for the
right thing to happen.
v2: Rebase on many, many changes. Move instruction source fixup
reordering out or try_constant_propagate.
v3: Rebase on !7698.
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/25091>
This annoyed me durning development of this MR. Every time I changed the
parameters to this internal function, I had to modify a public header
file... and trigger a much large rebuild.
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/25091>
If the linked list structure used depended on the list head to know when
to terminate, this would be a pretty serious bug. If try_constant_propage
or try_copy_propagate make progress, inst->src[i].nr will change. This
results in the foreach_in_list using a different list header on later
iterations of the loop.
This causes two shaders in shader-db and 9 shaders in fossil-db to
change. Looking at the code changes, these are cases where there was a
copy of a copy that gets propagated. The part that confuses me is the
VGRF numbers involved should **not** hash to the same bucket, so it
should be impossible to find the original source from the intermediate
VGRF.
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/25091>
Unless the change in liveout also causes livein to change, updates to
liveout cannot have any global effect. Changes to livein already flag
additional interation.
I had additional changes in this area that didn't pan out. While working
on those change, I was a little confused about this bit of code. It's
unnecessary, so it's better to delete it.
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/25091>
GLSL doesn't use that type. SPIR-V used for a while but later started
relying on its own data structures and stopped using it.
See ca62e849d3 ("nir/spirv: Stop using glsl_type for function types")
If we were ever to add this one again, would be better to have a way to
grab a key for lookup that did not require allocations, right now that's
needed to inject return type as the first element in params array.
Reviewed-by: Emma Anholt <emma@anholt.net>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/25160>
