The Intel bindless thread dispatch model is very simple. When a compute
shader is to be used for bindless dispatch, it can request a set of
stack IDs. These are allocated per-dual-subslice by the hardware and
recycled automatically when the stack ID is returned. Passed to the
bindless dispatch are a global argument address, a stack ID, and an
address of the BINDLESS_SHADER_RECORD to invoke. When the bindless
shader is dispatched, it is passed its stack ID as well as the global
and local argument pointers. The local argument pointer is the address
of the BINDLESS_SHADER_RECORD plus some offset which is specified as
part of the BINDLESS_SHADER_RECORD.
Reviewed-by: Caio Marcelo de Oliveira Filho <caio.oliveira@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/7356>
Motivation is to detect earlier certain bugs that can occur when
missing a check for the stage before using the downcast.
Reviewed-by: Marcin Ślusarz <marcin.slusarz@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/7540>
cs_prog_data->slm_size is basically redundant with
prog_data->total_shared, which is the field that we actually use for
controlling the shared local memory size in all drivers. We were
still using it in one place for VK_EXT_pipeline_executable_properties,
but we should just fix that and delete the field.
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/7152>
This will make the GL drivers pick the right SIMD variant for a given
group size set during dispatch. The heuristic implemented in
brw_cs_simd_size_for_group_size() is the same as in brw_compile_cs().
The cs_prog_data::simd_size field was removed. The generated SIMD
sizes are marked in a bitmask, which is already used via
brw_cs_simd_size_for_group_size() by the drivers.
When in variable group size, it is OK if larger SIMD shader spill,
since we'd need it for the cases where the smaller one can't hold all
the invocations.
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/5142>
Adding this since Iris will handle variable group size parameters by
itself.
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Jordan Justen <jordan.l.justen@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/4794>
This commit fixes performance regressions introduced by e03f965280
in which we started bounds checking our push constants. This added a
LOT of shader code to shaders which use the robustBufferAccess feature
and led to substantial spilling. The checking we just added to the FS
back-end is far more efficient for two reasons:
1. It can be done at a whole register granularity rather than per-
scalar and so we emit one SIMD8 SEL per 32B GRF rather than one
SIMD16 SEL (executed as two SELs) for each component loaded.
2. Because we do it with NoMask instructions, we can do it on whole
pushed GRFs without splatting them out to SIMD8 or SIME16 values.
This means that robust buffer access no longer explodes our register
pressure for no good reason.
As a tiny side-benefit, we're now using can use AND instead of SEL which
means no need for the flag and better scheduling.
Vulkan pipeline database results on ICL:
Instructions in all programs: 293586059 -> 238009118 (-18.9%)
SENDs in all programs: 13568515 -> 13568515 (+0.0%)
Loops in all programs: 149720 -> 149720 (+0.0%)
Cycles in all programs: 88499234498 -> 84348917496 (-4.7%)
Spills in all programs: 1229018 -> 184339 (-85.0%)
Fills in all programs: 1348397 -> 246061 (-81.8%)
This also improves the performance of a few apps:
- Shadow of the Tomb Raider: +4%
- Witcher 3: +3.5%
- UE4 Shooter demo: +2%
Reviewed-by: Caio Marcelo de Oliveira Filho <caio.oliveira@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/4447>
At this point all drivers are doing this math on their own -- since
most of them need to cover the variable group size case, in which at
compile time the group size (and number of threads) is not defined.
Reviewed-by: Jordan Justen <jordan.l.justen@intel.com>
Reviewed-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/4504>
Add new builtin parameters that are used to keep track of the group
size. This will be used to implement ARB_compute_variable_group_size.
The compiler will use the maximum group size supported to pick a
suitable SIMD variant. A later improvement will be to keep all SIMD
variants (like FS) so the driver can select the best one at dispatch
time.
When variable workgroup size is used, the small workgroup optimization
is disabled as it we can't prove at compile time that the barriers
won't be needed.
Extracted from original i965 patch with additional changes by
Caio Marcelo de Oliveira Filho.
Reviewed-by: Caio Marcelo de Oliveira Filho <caio.oliveira@intel.com>
Reviewed-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: Jordan Justen <jordan.l.justen@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/4504>
The push.total field had three values but only one was directly
used (size). Replace it with a helper function that explicitly takes
the cs_prog_data and the number of threads -- and use that in the
drivers.
This is a preparation for ARB_compute_variable_group_size where the
number of threads (hence the total size for push constants) is not
defined at compile time (not cs_prog_data->threads).
Reviewed-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: Jordan Justen <jordan.l.justen@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/4504>
Change brw_compute_vue_map() to also take the number of pos slots. If
more than one slot is used, the VARYING_SLOT_POS is treated as an
array.
When using Primitive Replication, instead of a single position, the
VUE must contain an array of positions. Padding might be
necessary (after clip distance) to ensure rest of attributes start
aligned.
v2: Add note about array in the commit message and assert that
pos_slots >= 1 to make clear 0 is invalid. (Jason)
Move padding to be after the clip distance.
v3: Apply the correct offset when gathering the sources from outputs.
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net> [v2]
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Rafael Antognolli <rafael.antognolli@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/2313>
Store the fragment shader inputs in the program data so we can use them
later when required without needing the NIR shader.
Cc: mesa-stable@lists.freedesktop.org
Signed-off-by: Juan A. Suarez Romero <jasuarez@igalia.com>
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
Reviewed-by: Ivan Briano <ivan.briano@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/2010>
Return the number of patches to accumulate before an 8_PATCH mode thread
is launched.
v2: (Kenneth Graunke)
- Track patch count threshold instead of input control points.
Signed-off-by: Sagar Ghuge <sagar.ghuge@intel.com>
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/3563>
Patch adds a new arg and modifies existing calls from i965, anv
pass NULL but iris stores this information for later use.
Signed-off-by: Tapani Pälli <tapani.palli@intel.com>
Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/4080>
Avoid looping over all VARYING_SLOT_MAX urb_setup array
entries from genX_upload_sbe. Prepare an array indirection
to the active entries of urb_setup already in the compile
step. On upload only walk the active arrays.
v2: Use uint8_t to store the attribute numbers.
v3: Change loop to build up the array indirection.
v4: Rebase.
v5: Style fix.
Reviewed-by: Matt Turner <mattst88@gmail.com>
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
Signed-off-by: Mathias Fröhlich <Mathias.Froehlich@web.de>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/308>
Currently the "Source0 Alpha Present to RenderTarget" bit of the RT
write message header is derived from brw_wm_prog_data::replicate_alpha.
However the src0_alpha payload is provided anytime it's specified to
the logical message. This could theoretically lead to an
inconsistency if somebody provided a src0_alpha value while
brw_wm_prog_data::replicate_alpha was false, as I'm planning to do in
a future commit in order to implement a hardware workaround.
Instead calculate the header bit based on whether a src0_alpha value
was provided to the logical message, which guarantees the same
behavior on pre-ICL and ICL+ (the latter used an extended descriptor
bit for this which didn't suffer from the same issue). Remove the
brw_wm_prog_data::replicate_alpha flag.
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
This is mainly meant to avoid shader-db regressions on SNB as we start
using VGRFs for barycentrics more frequently. Currently the
aligned_pairs_class is only useful in SIMD8 mode, because in SIMD16
mode barycentric vectors are typically 4 GRFs. This is not a problem
on Gen4-5, because on those platforms all VGRF allocations are
pair-aligned in SIMD16 mode. However on Gen6 we end up using either
the fast or the slow path of LINTERP rather non-deterministically
based on the behavior of the register allocator.
Fix it by repurposing aligned_pairs_class to hold PLN-aligned
registers of whatever the natural size of a barycentric vector is in
the current dispatch width.
On SNB this prevents the following shader-db regressions (including
SIMD32 programs) in combination with the interpolation rework part of
this series:
total instructions in shared programs: 13983257 -> 14527274 (3.89%)
instructions in affected programs: 1766255 -> 2310272 (30.80%)
helped: 0
HURT: 11608
LOST: 26
GAINED: 13
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Confirmed no regressions after a full Piglit run on TGL with the
brw_fs_test_dispatch_packing() test enabled.
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
I would like for iris to be able to avoid setting up SURFACE_STATE
for UBOs in the common case where all constants are pushed.
Unfortunately, we don't know up front whether everything will be
pushed: the backend is allowed to demote pushed UBOs to pull loads
fairly late in the process. This is probably desirable though, as
we'd like the backend to be able to re-pull pushed data to break up
long live ranges in response to register pressure.
Here we simply add a "are there any pull loads at all" boolean to
prog_data, which is a bit crude but at least allows us to skip work
in the common "everything pushed" case. We could skip more work by
tracking exactly which UBO surfaces are pulled in a bitmask, but I
wanted to avoid bringing back the old mark_surface_used() mechanism.
Finer-grained tracking could allow us to skip a bit more work when
multiple UBOs are in use and /some/ are 100% pushed, but others are
accessed via pulls. However, I'm not sure how common this is and
it would save at most 4 pull descriptors, so we defer that for now.
Reviewed-by: Caio Marcelo de Oliveira Filho <caio.oliveira@intel.com>
It's not used by anything anymore now that so much lowering has been
moved into NIR. Sadly, we still need on in brw_compile_gs() for
geometry shaders on Sandy Bridge. Short of a lot of pointless work,
that one's probably not going away.
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
We don't need it for state setup but it's a useful statistic we want to
pass on to developers.
Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
This commit is all annoying plumbing work which just adds support for a
new brw_compile_stats struct. This struct provides a binary driver
readable form of the same statistics we dump out to stderr when we
INTEL_DEBUG is set with a shader stage.
Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Suggested-by: Jason Ekstrand <jason@jlekstrand.net>
Signed-off-by: Eric Engestrom <eric.engestrom@intel.com>
Reviewed-by: Matt Turner <mattst88@gmail.com>
The rules for gl_SubgroupSize in Vulkan require that it be a constant
that can be queried through the API. However, all GL requires is that
it's a uniform. Instead of always claiming that the subgroup size in
the shader is 32 in GL like we have to do for Vulkan, claim 8 for
geometry stages, the maximum for fragment shaders, and the actual size
for compute.
Reviewed-by: Caio Marcelo de Oliveira Filho <caio.oliveira@intel.com>
Right now, all keys have two things in common: a program string ID and a
sampler_prog_key_data. I'd like to add another thing or two and need a
place to put it. This commit adds a new brw_base_prog_key struct which
contains those two common bits.
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Our tessellation control shaders can be dispatched in several modes.
- SINGLE_PATCH (Gen7+) processes a single patch per thread, with each
channel corresponding to a different patch vertex. PATCHLIST_N will
launch (N / 8) threads. If N is less than 8, some channels will be
disabled, leaving some untapped hardware capabilities. Conditionals
based on gl_InvocationID are non-uniform, which means that they'll
often have to execute both paths. However, if there are fewer than
8 vertices, all invocations will happen within a single thread, so
barriers can become no-ops, which is nice. We also burn a maximum
of 4 registers for ICP handles, so we can compile without regard for
the value of N. It also works in all cases.
- DUAL_PATCH mode processes up to two patches at a time, where the first
four channels come from patch 1, and the second group of four come
from patch 2. This tries to provide better EU utilization for small
patches (N <= 4). It cannot be used in all cases.
- 8_PATCH mode processes 8 patches at a time, with a thread launched per
vertex in the patch. Each channel corresponds to the same vertex, but
in each of the 8 patches. This utilizes all channels even for small
patches. It also makes conditions on gl_InvocationID uniform, leading
to proper jumps. Barriers, unfortunately, become real. Worse, for
PATCHLIST_N, the thread payload burns N registers for ICP handles.
This can burn up to 32 registers, or 1/4 of our register file, for
URB handles. For Vulkan (and DX), we know the number of vertices at
compile time, so we can limit the amount of waste. In GL, the patch
dimension is dynamic state, so we either would have to waste all 32
(not reasonable) or guess (badly) and recompile. This is unfortunate.
Because we can only spawn 16 thread instances, we can only use this
mode for PATCHLIST_16 and smaller. The rest must use SINGLE_PATCH.
This patch implements the new 8_PATCH TCS mode, but leaves us using
SINGLE_PATCH by default. A new INTEL_DEBUG=tcs8 flag will switch to
using 8_PATCH mode for testing and benchmarking purposes. We may
want to consider using 8_PATCH mode in Vulkan in some cases.
The data I've seen shows that 8_PATCH mode can be more efficient in
some cases, but SINGLE_PATCH mode (the one we use today) is faster
in other cases. Ultimately, the TES matters much more than the TCS
for performance, so the decision may not matter much.
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
The i965 driver has a bunch of code to compare two sets of program keys
and print out the differences. This can be useful for debugging why a
shader needed to be recompiled on the fly due to non-orthogonal state
dependencies. anv doesn't do recompiles, so we didn't need to share
this in the past - but I'd like to use it in iris.
This moves the bulk of the code to the compiler where it can be reused.
To make that possible, we need to decouple it from i965 - we can't get
at the brw program cache directly, nor use brw_context to print things.
Instead, we use compiler->shader_perf_log(), and simply pass in keys.
We put all of this debugging code in brw_debug_recompile.c, and only
export a single function, for simplicity. I also tidied the code a
bit while moving it, now that it all lives in one file.
Reviewed-by: Jordan Justen <jordan.l.justen@intel.com>
From "Alpha Coverage" section of SKL PRM Volume 7:
"If Pixel Shader outputs oMask, AlphaToCoverage is disabled in
hardware, regardless of the state setting for this feature."
From OpenGL spec 4.6, "15.2 Shader Execution":
"The built-in integer array gl_SampleMask can be used to change
the sample coverage for a fragment from within the shader."
From OpenGL spec 4.6, "17.3.1 Alpha To Coverage":
"If SAMPLE_ALPHA_TO_COVERAGE is enabled, a temporary coverage value
is generated where each bit is determined by the alpha value at the
corresponding sample location. The temporary coverage value is then
ANDed with the fragment coverage value to generate a new fragment
coverage value."
Similar wording could be found in Vulkan spec 1.1.100
"25.6. Multisample Coverage"
Thus we need to compute alpha to coverage dithering manually in shader
and replace sample mask store with the bitwise-AND of sample mask and
alpha to coverage dithering.
The following formula is used to compute final sample mask:
m = int(16.0 * clamp(src0_alpha, 0.0, 1.0))
dither_mask = 0x1111 * ((0xfea80 >> (m & ~3)) & 0xf) |
0x0808 * (m & 2) | 0x0100 * (m & 1)
sample_mask = sample_mask & dither_mask
Credits to Francisco Jerez <currojerez@riseup.net> for creating it.
It gives a number of ones proportional to the alpha for 2, 4, 8 or 16
least significant bits of the result.
GEN6 hardware does not have issue with simultaneous usage of sample mask
and alpha to coverage however due to the wrong sending order of oMask
and src0_alpha it is still affected by it.
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=109743
Signed-off-by: Danylo Piliaiev <danylo.piliaiev@globallogic.com>
Reviewed-by: Francisco Jerez <currojerez@riseup.net>
The parameter is never used, and it's not part of a common interface
idiom. Remove it.
src/intel/compiler/brw_interpolation_map.c: In function ‘brw_setup_vue_interpolation’:
src/intel/compiler/brw_interpolation_map.c:62:59: warning: unused parameter ‘devinfo’ [-Wunused-parameter]
const struct gen_device_info *devinfo)
^~~~~~~
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
Add support to the i965 DRI driver to sample from XYUV8888 buffers.
Signed-off-by: Vivek Kasireddy <vivek.kasireddy@intel.com>
Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Reviewed-by: Tapani Pälli <tapani.palli@intel.com>
Reviewed-by: Eric Engestrom <eric.engestrom@intel.com>
