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>
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>
The original idea was that the backend compiler could eliminate
surfaces, so we would have it mark which ones are actually used,
then shrink the binding table accordingly. Unfortunately, it's a
pretty blunt mechanism - it can only prune things from the end,
not the middle - since we decide the layout before we even start
the backend compiler, and only limit the size. It also basically
gives up if it sees indirect array access.
Besides, we do the vast majority of our surface elimination in NIR
anyway, not the backend - and I don't see that trend changing any
time soon. Vulkan abandoned this plan a long time ago, and I don't
use it in Iris, but it's still been kicking around in i965.
I hacked shader-db to print the binding table size in bytes, and
observed no changes with this patch. So, this code appears to do
nothing useful.
Acked-by: Jason Ekstrand <jason@jlekstrand.net>
This moves nir_shader_clone() to the driver-specific compile function,
rather than the shared src/intel/compiler code. This allows i965 to do
key-specific passes before calling brw_compile_*. Vulkan should not
need this cloning as it doesn't compile multiple variants.
We do need to continue cloning in the compute shader code because we
lower various things in NIR based on the SIMD width.
Reviewed-by: Alejandro Piñeiro <apinheiro@igalia.com>
Now that the drivers are lowering to surface indices themselves, we no
longer need to push the surface index into the shader.
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
During code review, Jason pointed out that:
2b3064c073 "i965, anv: Use INTEL_DEBUG for disk_cache driver flags"
Didn't account for INTEL_SCALER_* environment variables.
To fix this, let the compiler return the disk_cache driver flags.
Another possible fix would be to pull the INTEL_SCALER_* into
INTEL_DEBUG bits, but as we are currently using 41 of 64 bits, I
didn't think it was a good use of 4 more of these bits. (5 since
INTEL_PRECISE_TRIG needs to be accounted for as well.)
Cc: Jason Ekstrand <jason@jlekstrand.net>
Signed-off-by: Jordan Justen <jordan.l.justen@intel.com>
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Instead of just looking at the number of color attachments, look at
which ones are actually used by the subpass. This lets us potentially
throw away chunks of the fragment shader. In DXVK, for example, all
subpasses have 8 attachments and most are VK_ATTACHMENT_UNUSED so this
is very helpful in that case.
Reviewed-by: Timothy Arceri <tarceri@itsqueeze.com>
According to RenderDoc, this shaves 99.6% of the run time off of the
ambient occlusion pass in Skyrim Special Edition when running under DXVK
and shaves 92% off the runtime for a reasonably representative frame.
When running the actual game, Skyrim goes from being a slide-show to a
very stable and playable framerate on my SKL GT4e machine.
Reviewed-by: Timothy Arceri <tarceri@itsqueeze.com>
Reviewed-by: Iago Toral Quiroga <itoral@igalia.com>
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
The pixel shader dispatch table is kind-of a confusing mess. This adds
some helpers for dealing with it and for easily extracting the correct
data from wm_prog_data.
Reviewed-by: Matt Turner <mattst88@gmail.com>
- remove mtypes.h from most header files
- add main/menums.h for often used definitions
- remove main/core.h
v2: fix radv build
Reviewed-by: Brian Paul <brianp@vmware.com>
Rafael ran piglit with the test code enabled and saw no additional GPU
hangs.
Reviewed-by: Matt Turner <mattst88@gmail.com>
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
This requires us to bump the subgroup size to 32 for all shader stages
because Vulkan requires that to be a physical device query.
Reviewed-by: Iago Toral Quiroga <itoral@igalia.com>
This is part of the device groups extension/feature but it's a decent
chunk of work in its own right so it's worth breaking into its own
patch. The mechanism we use is fairly straightforward: we just push the
base work group id into the shader and add it to the work group id we
get from dispatch.
Reviewed-by: Samuel Iglesias Gonsálvez <siglesias@igalia.com>
Split out the device info so isl doesn't depend on intel/common. Now
it will depend on the new intel/dev device info lib.
This will allow the decoder in intel/common to use isl, allowing us to
apply Ken's patch that removes the genxml duplication of surface
formats.
Signed-off-by: Jordan Justen <jordan.l.justen@intel.com>
Reviewed-by: Samuel Iglesias Gonsálvez <siglesias@igalia.com>
We have to start render targets at binding table index 0 in order to use
headerless FB write messages, and in fact already assume this in a bunch
of places in the code. Let's finish that off, and not bother storing 0
in a struct to pretend to add it in a few places.
Reviewed-by: Iago Toral Quiroga <itoral@igalia.com>
Older OpenGL defines two equations for converting from signed-normalized
to floating point data. These are:
f = (2c + 1)/(2^b - 1) (equation 2.2)
f = max{c/2^(b-1) - 1), -1.0} (equation 2.3)
Both OpenGL 4.2+ and OpenGL ES 3.0+ mandate that equation 2.3 is to be
used in all scenarios, and remove equation 2.2. DirectX uses equation
2.3 as well. Intel hardware only supports equation 2.3, so Gen7.5+
systems that use the vertex fetcher hardware to do the conversions
always get formula 2.3.
This can make a big difference for 10-10-10-2 formats - the 2-bit value
can represent 0 with equation 2.3, and cannot with equation 2.2.
Ivybridge and older were using equation 2.2 for OpenGL, and 2.3 for ES.
Now that Ivybridge supports OpenGL 4.2, this is wrong - we need to use
the new rules, at least in core profile. That would leave Gen4-6 doing
something different than all other hardware, which seems...lame.
With context version promotion, applications that requested a pre-4.2
context may get promoted to 4.2, and thus get the new rules. Zero cases
have been reported of this being a problem. However, we've received a
report that following the old rules breaks expectations. SuperTuxKart
apparently renders the cars red when following equation 2.2, and works
correctly when following equation 2.3:
https://github.com/supertuxkart/stk-code/issues/2885#issuecomment-353858405
So, this patch deletes the legacy equation 2.2 support entirely, making
all hardware and APIs consistently use the new equation 2.3 rules.
If we ever find an application that truly requires the old formula, then
we'd likely want that application to work on modern hardware, too. We'd
likely restore this support as a driconf option. Until then, drop it.
This commit will regress Piglit's draw-vertices-2101010 test on
pre-Haswell without the corresponding Piglit patch to accept either
formula (commit 35daaa1695ea01eb85bc02f9be9b6ebd1a7113a1):
draw-vertices-2101010: Accept either SNORM conversion formula.
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
Reviewed-by: Chris Forbes <chrisforbes@google.com>
We use the same hardware mechanism for both atomic counters and SSBO
atomics, so there's really no benefit to maintaining separate code to
handle each case. Instead, we can just use Rob's shiny new NIR pass to
convert atomic_uints to SSBOs, and delete piles of code.
The ssbo_start section of the binding table becomes a combined ABO and
SSBO section, with ABOs first, then SSBOs.
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
We're going to want subgroup ID for SPIR-V subgroups eventually anyway.
We really only want to push one and calculate the other from it. It
makes a bit more sense to push the subgroup ID because it's simpler to
calculate and because it's a real API thing. The only advantage to
pushing the base thread ID is to avoid a single SHL in the shader.
Reviewed-by: Iago Toral Quiroga <itoral@igalia.com>
This will be used by the on disk shader cache.
v2:
* Set in brw_compile_* rather than brw_codegen_*. (Jason)
Signed-off-by: Timothy Arceri <timothy.arceri@collabora.com>
[jordan.l.justen@intel.com: Only add to brw_stage_prog_data]
Signed-off-by: Jordan Justen <jordan.l.justen@intel.com>
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
This is a lot more natural than special casing it all over the place.
We still have to do a bit of special-casing in assign_constant_locations
but it's not special-cased quite as bad as it was before.
Reviewed-by: Jordan Justen <jordan.l.justen@intel.com>
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
