We say that they're for debug only but we don't really have a good
policy around when to set them and when not to. In particular,
nir_lower_system_values and nir_lower_vars_to_ssa which are the chief
producers of SSA values which might reasonably have a name do not bother
to set one. We have some names set from things like BLORP and RADV's
meta shaders but AFAICT, they're setting a name more because it's there
than because they actually care.
Also, most things other than nir_clone and nir_serialize don't bother to
try and preserve them. You can see in the diffstat of this commit
exactly what passes attempt to preserve names. Notably missing from the
list is opt_algebraic which is the single largest source of SSA def
churn and it happily throws names away.
These observations lead me to question whether or not names are actually
useful at all or if they're just taking up space (8B per instruction)
and wasting CPU cycles (to ralloc_strdup on the off chance we do have
one). I don't think I can think of a single time in recent history
where I've been debugging a shader issue and a SSA value name has been
there and been useful. If anything, the few times they are there, they
just throw me off because they mess up the indentation in nir_print.
iris shader-db on my system gets runtime -2.07734% +/- 1.26933% (n=5)
Reviewed-by: Emma Anholt <emma@anholt.net>
Reviewed-by: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/5439>
The way that the blob obtains the subgroup id on compute shaders is by
just and'ing gl_LocalInvocationIndex with 63, since it advertizes a
subgroupSize of 64. In order to support VK_EXT_subgroup_size_control and
expose a subgroupSize of 128, we'll have to do something a little more
flexible. Sometimes we have to fall back to a subgroup size of 64 due to
various constraints, and in that case we have to fake a subgroup size of
128 while actually using 64 under the hood, by just pretending that the
upper 64 invocations are all disabled. However when computing the
subgroup id we need to use the "real" subgroup size. For this purpose we
plumb through a driver param which exposes the real subgroup size. If
the user forces a particular subgroup size then we lower
load_subgroup_size in nir_lower_subgroups, otherwise we let it through,
and we assume when translating to ir3 that load_subgroup_size means
"give me the *actual* subgroup size that you decided in RA" and give you
the driver param.
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/6752>
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>
Reduces the work that other shader passes have to do to look at dead code,
and possibly extra rounds around the optimization loop if dce wasn't the
last pass in it.
shader-db runtime -1.12919% +/- 0.264337% (n=49) on SKL.
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/11628>
ifind_msb_rev was introduced in a5747f8ab3.
ifind_msb_rev guards against src0 being both 0 or -1 at the same time.
That is always true. This patch changes it to check for those values
individually.
Spotted from a compile warning.
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
Fixes: a5747f8ab3 (\"nir: add opcodes for *find_msb_rev and lowering\")
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/11630>
For images, variable data includes the format. For samplers, variable
data is used for OpenCL inline samplers. When converting a variable
from one to the other, zero out the data so we don't accidentally
interpret a converted image as an inline sampler.
Fixes: fa677c86 ("nir_lower_readonly_images_to_tex: Support non-CL semantics")
Acked-by: Enrico Galli <enrico.galli@intel.com>
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/11674>
This should be a subtract, not an add. The comment's proof is correct,
but the (wrong) expression we actually use isn't what it's in the
comment! Correct the discrepancy.
The lowering in nir_opt_algebraic was correctly typed.
Fixes: 272e927d0e ("nir/spirv: initial handling of OpenCL.std extension opcodes")
Signed-off-by: Alyssa Rosenzweig <alyssa@collabora.com>
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
Reviewed-by: Karol Herbst <kherbst@redhat.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/11671>
In addition to register pressure benefits from getting more fp16/int16,
this avoids i2imp's from standing in the way of loop unrolling.
Signed-off-by: Rob Clark <robdclark@chromium.org>
Reviewed-by: Connor Abbott <cwabbott0@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/11545>
Compiling with clang warns about an unused variable in
nir_lower_packing.
Tracking progress was added to nir_lower_packing in
adb157ddfd but the function
will ignore the progress from impl calls and always return
false.
This patch changes it to return the progress. It fixes the
warning and should enable validation calls in NIR_PASS when
progress is made.
Reviewed-by: Christian Gmeiner <christian.gmeiner@gmail.com>
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
Fixes: adb157ddfd "nir: Return progress from nir_lower_64bit_pack()"
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/11615>
Static struct bitset was renamed to brw_bitset as a struct bitset
is defined in sys/_bitset.h included by pthread_np.h on FreeBSD that
is indirectly included by src/intel/compiler/brw_nir_lower_shader_calls.c
Signed-off-by: Eleni Maria Stea <elene.mst@gmail.com>
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/11203>
Sometimes you might want to find a constant source without going through
all the copy prop and constant folding to make your source be a
load_const.
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
Reviewed-by: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/11613>
We could do better if we knew the nir_address_format to obtain
addition_bits, but the only affected driver (Turnip) probably won't
benefit because it doesn't vectorize across vec4.
Signed-off-by: Rhys Perry <pendingchaos02@gmail.com>
Reviewed-by: Daniel Schürmann <daniel@schuermann.dev>
Fixes: 2e7bceb220 ("nir/load_store_vectorizer: fix check_for_robustness() with indirect loads")
Closes: https://gitlab.freedesktop.org/mesa/mesa/-/issues/4922
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/11382>
Some infinite loop cases were already covered by other
restrictions (e.g. if the loop had a body), but the case with a single
block in the loop body wasn't yet.
This prevents an infinite loop when optimizing the shader in
dEQP-VK.reconvergence.subgroup_uniform_control_flow_ballot.compute.nesting2.3.2
and various others reconvergence tests.
Fixes: 0881e90c09 ("nir: Split ALU instructions in loops that read phis")
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com> [v1]
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/11476>
This is now 100% equivalent to the new rt_resume intrinsic.
Signed-off-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/8637>
Really copying Jason's pass.
Changes:
- Instead of all the intel lowering introduce rt_{execute_callable,trace_ray,resume}
- Add the ability to use scratch intrinsics directly.
Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/10339>
About half or more of the text here is actually from Connor Abbot. I've
edited it a bit to bring it up-to-date and make a few things more clear.
Reviewed-by: Connor Abbott <cwabbott0@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/11438>
Long ago, the semantics of bcsel were such that it took a single boolean
value and selected between whole vectors. These days, it takes a vector
boolean with the assumption that if you want the old behavior you can
just use a .xxxx swizzle. There currently are no opcodes which use a
output_size of 0 but have a scalar or fixed-vector input. Let's
disallow it for now to force us to think through the semantics again if
this ever comes up as something someone actually wants.
Reviewed-by: Connor Abbott <cwabbott0@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/11438>
For debug on Android, it's useful to be able to print shaders to the
android log interface, since you don't usually have stdout/stderr.
Reviewed-by: Rob Clark <robdclark@chromium.org>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/9262>
limit==0 is the signal for "don't peephole anything but a move that will
be optimized aways." limit > 0 is "up to N alu instructions may be moved
out." nir-to-tgsi uses ~0 as the indicator of "No, we really need to
eliminate all if instructions" on hardware like i915 that doesn't have
control flow.
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
Reviewed-by: Adam Jackson <ajax@redhat.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/11329>
We need to make get it updated after we may have nir_instr_remove()d an
instruction, and when we cross blocks. This didn't really matter before
because the only builder usage was idiv, which other users of
lower_int_to_float were probably never hitting.
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
Reviewed-by: Adam Jackson <ajax@redhat.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/11329>
Use a single set and ensure dominance by checking after a equivalent
instruction is found.
Besides removing the need to copy a set, this also lets us resize the set
at the start of the pass in the next commit.
ministat (CSE only):
Difference at 95.0% confidence
-984.956 +/- 28.8559
-6.90075% +/- 0.190231%
(Student's t, pooled s = 26.9052)
ministat (entire run):
Difference at 95.0% confidence
-1246.1 +/- 257.253
-0.998972% +/- 0.205094%
(Student's t, pooled s = 239.863)
Signed-off-by: Rhys Perry <pendingchaos02@gmail.com>
Co-authored-by: Daniel Schürmann <daniel@schuermann.dev>
Reviewed-by: Daniel Schürmann <daniel@schuermann.dev>
Reviewed-by: Rhys Perry <pendingchaos02@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/6390>
Now that there's a common NIR pass, there's no point in us doing this in
the back-end anymore. In order to use this pass in i965, we do have to
make one tiny change. Gallium runs the pass after assigning input and
output locations and so needs the pass to respect those locations and
num_inputs. i965, however, runs it before any location assignment or
I/O lowering so we don't care. We do, however, need the pass to succeed
with num_inputs == 0 because we set that later.
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/11313>
In theory you can rerun the info gather pass, but in practice that
doesn't always end well. Be consistent inside this pass and update the
info.
While we're here, change the inputs read to use VERT_BIT_EDGEFLAG.
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/11313>
The v_mbcnt instructions can take an extra source that they add to
the result. This is not exposed in SPIR-V but we now expose it in NIR.
Signed-off-by: Timur Kristóf <timur.kristof@gmail.com>
Reviewed-by: Tony Wasserka <tony.wasserka@gmx.de>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/11072>
These map directly to v_perm_b32 and v_permlane_b32.
Unfortunately there is no corresponding NIR opcode or
intrinsics, and it's too tedious to puzzle these things
together from the existing NIR instructions.
Signed-off-by: Timur Kristóf <timur.kristof@gmail.com>
Reviewed-by: Tony Wasserka <tony.wasserka@gmx.de>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/11072>
NIR currently doesn't have any intrinsics for a horizontal packed add,
so this one is modeled after AMD's v_sad_u8.
Signed-off-by: Timur Kristóf <timur.kristof@gmail.com>
Reviewed-by: Tony Wasserka <tony.wasserka@gmx.de>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/11072>
The helpers will be reused for per-primitive variables that are also
arrayed, so use a more general name.
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Timur Kristóf <timur.kristof@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/11252>
