When lowering a single instruction with a destination VGRF to 2 or
more, the VGRF is now considered partially written by each generated
instruction and that increases its liveness especially in loops. Thus
potentially increasing the number of spills/fills due to register
allocation.
Putting an UNDEF instruction in front of the lowered instructions
allows the IR to limit the liveness of the VGRF, reducing register
pressure.
This has a pretty dramatic effect on spills/fills for RT shaders. Here
the stats on Q2RTX shaders on DG2 (wipping out any spills/fills due to
register allocation) :
Instructions in all programs: 26150 -> 24955 (-4.6%)
SENDs in all programs: 1148 -> 1148 (+0.0%)
Loops in all programs: 4 -> 4 (+0.0%)
Cycles in all programs: 392179 -> 332787 (-15.1%)
Spills in all programs: 132 -> 116 (-12.1%)
Fills in all programs: 262 -> 154 (-41.2%)
Shader-db results on TGL :
total instructions in shared programs: 21158140 -> 21158377 (<.01%)
instructions in affected programs: 76629 -> 76866 (0.31%)
helped: 18
HURT: 20
helped stats (abs) min: 1 max: 60 x̄: 18.89 x̃: 12
helped stats (rel) min: 0.21% max: 3.61% x̄: 1.02% x̃: 0.77%
HURT stats (abs) min: 1 max: 79 x̄: 28.85 x̃: 18
HURT stats (rel) min: 0.04% max: 2.81% x̄: 1.13% x̃: 0.79%
95% mean confidence interval for instructions value: -4.82 17.30
95% mean confidence interval for instructions %-change: -0.34% 0.57%
Inconclusive result (value mean confidence interval includes 0).
total loops in shared programs: 5753 -> 5753 (0.00%)
loops in affected programs: 0 -> 0
helped: 0
HURT: 0
total cycles in shared programs: 798856834 -> 798870688 (<.01%)
cycles in affected programs: 6208395 -> 6222249 (0.22%)
helped: 22
HURT: 17
helped stats (abs) min: 2 max: 8794 x̄: 1438.18 x̃: 782
helped stats (rel) min: 0.05% max: 2.28% x̄: 0.63% x̃: 0.44%
HURT stats (abs) min: 2 max: 19178 x̄: 2676.12 x̃: 1358
HURT stats (rel) min: 0.04% max: 23.49% x̄: 2.25% x̃: 0.71%
95% mean confidence interval for cycles value: -952.19 1662.65
95% mean confidence interval for cycles %-change: -0.64% 1.90%
Inconclusive result (value mean confidence interval includes 0).
total spills in shared programs: 4078 -> 4066 (-0.29%)
spills in affected programs: 40 -> 28 (-30.00%)
helped: 2
HURT: 0
total fills in shared programs: 2856 -> 2832 (-0.84%)
fills in affected programs: 127 -> 103 (-18.90%)
helped: 2
HURT: 0
total sends in shared programs: 998554 -> 998554 (0.00%)
sends in affected programs: 0 -> 0
helped: 0
HURT: 0
LOST: 0
GAINED: 0
Total CPU time (seconds): 2346.06 -> 2304.80 (-1.76%)
Signed-off-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Reviewed-by: Francisco Jerez <currojerez@riseup.net>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/18657>
NIR has two implementations of lower_idiv, keyed on the
imprecise_32bit_lowering flag. This flag is misleading: the results when
setting this flag "imprecise", they're completely wrong for some values.
If a backend has a native implementation of umul_high, the correct path
isn't that much more expensive. If it doesn't, it's substantially slower
for highp integer divison... but in practice, non-constant highp integer
division is pretty rare.
After a painful migration of the tree, this code path has no more users.
Remove it so nobody else gets the bright idea of using it again.
Closes: #6555
Signed-off-by: Alyssa Rosenzweig <alyssa@collabora.com>
Reviewed-by: Emma Anholt <emma@anholt.net>
Reviewed-by: Christian Gmeiner <christian.gmeiner@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/19303>
That was previously listed on the getopt_long struct but not actually
being used. This makes intel_clc argument processing easier as now
all of its arguments are handled with getopt and anything after the
special argument '--' is passed along to clang to form the final build
command.
Thanks to Dylan Baker for help with changes to the meson file.
Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/19153>
VK_PIPELINE_CREATE_RAY_TRACING_SKIP_AABBS_BIT_KHR and
VK_PIPELINE_CREATE_RAY_TRACING_SKIP_TRIANGLES_BIT_KHR, when specified,
make TraceRay behave as if the corresponding shader flags were set, but
without affecting the value of IncomingRayFlags in shaders.
v2 (Lionel): Improve comments
Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/19152>
Setting the NIR options takes care of iris thanks to the common st/mesa
linking code, and updating brw_nir_link_shaders should handle anv.
The main effort here is updating remap_tess_levels, which needs to
handle vector stores, writemasking, and swizzling. Unfortunately,
we also need to continue handling the existing single-component
access because it's used for TES inputs, which we don't vectorize.
We could try to vectorize TES inputs too, but they're all pushed
anyway, so it wouldn't buy us much other than deleting this code.
Also, we do have opt_combine_stores, but not one for loads.
One limitation of using nir_vectorize_tess_levels is that it works
on variables, and so isn't able to combine outer/inner writes that
happen to live in the same vec4 slot (for triangle domains). That
said, it's still better than before.
For writes, we allow the intrinsics to supply up to the full size
of the variable (vec4 for outer, vec2 for inner) even if the domain
only requires a subset of those components (i.e. triangles needs 3).
shader-db results on Icelake:
total instructions in shared programs: 19600314 -> 19597528 (-0.01%)
instructions in affected programs: 65338 -> 62552 (-4.26%)
helped: 271 / HURT: 0
helped stats (abs) min: 6 max: 24 x̄: 10.28 x̃: 12
helped stats (rel) min: 1.30% max: 18.18% x̄: 5.80% x̃: 7.59%
95% mean confidence interval for instructions value: -10.71 -9.85
95% mean confidence interval for instructions %-change: -6.17% -5.43%
Instructions are helped.
total cycles in shared programs: 851842332 -> 851808165 (<.01%)
cycles in affected programs: 618577 -> 584410 (-5.52%)
helped: 271 / HURT: 0
helped stats (abs) min: 64 max: 540 x̄: 126.08 x̃: 111
helped stats (rel) min: 2.57% max: 37.97% x̄: 6.12% x̃: 5.06%
95% mean confidence interval for cycles value: -135.35 -116.80
95% mean confidence interval for cycles %-change: -6.67% -5.57%
Cycles are helped.
total sends in shared programs: 1025238 -> 1024308 (-0.09%)
sends in affected programs: 6454 -> 5524 (-14.41%)
helped: 271 / HURT: 0
helped stats (abs) min: 2 max: 8 x̄: 3.43 x̃: 4
helped stats (rel) min: 5.71% max: 25.00% x̄: 14.98% x̃: 17.39%
95% mean confidence interval for sends value: -3.57 -3.29
95% mean confidence interval for sends %-change: -15.42% -14.54%
Sends are helped.
According to Felix DeGrood, this results in a 10% improvement in
the draw call time for certain draw calls from Strange Brigade.
v2: Fix assertions about number of components and add more of them.
Combine the quads and triangles handling as it's nearly identical.
Reviewed-by: Caio Oliveira <caio.oliveira@intel.com> [v1]
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/19061>
Setting the NIR options takes care of iris thanks to the common st/mesa
linking code, and updating brw_nir_link_shaders should handle anv.
The main effort here is updating remap_tess_levels, which needs to
handle vector stores, writemasking, and swizzling. Unfortunately,
we also need to continue handling the existing single-component
access because it's used for TES inputs, which we don't vectorize.
We could try to vectorize TES inputs too, but they're all pushed
anyway, so it wouldn't buy us much other than deleting this code.
Also, we do have opt_combine_stores, but not one for loads.
One limitation of using nir_vectorize_tess_levels is that it works
on variables, and so isn't able to combine outer/inner writes that
happen to live in the same vec4 slot (for triangle domains). That
said, it's still better than before.
For writes, we allow the intrinsics to supply up to the full size
of the variable (vec4 for outer, vec2 for inner) even if the domain
only requires a subset of those components (i.e. triangles needs 3).
shader-db results on Icelake:
total instructions in shared programs: 19605070 -> 19602284 (-0.01%)
instructions in affected programs: 65338 -> 62552 (-4.26%)
helped: 271 / HURT: 0
helped stats (abs) min: 6 max: 24 x̄: 10.28 x̃: 12
helped stats (rel) min: 1.30% max: 18.18% x̄: 5.80% x̃: 7.59%
95% mean confidence interval for instructions value: -10.71 -9.85
95% mean confidence interval for instructions %-change: -6.17% -5.43%
Instructions are helped.
total cycles in shared programs: 851854659 -> 851820320 (<.01%)
cycles in affected programs: 618749 -> 584410 (-5.55%)
helped: 271 / HURT: 0
helped stats (abs) min: 69 max: 540 x̄: 126.71 x̃: 108
helped stats (rel) min: 2.57% max: 37.97% x̄: 6.17% x̃: 5.06%
95% mean confidence interval for cycles value: -135.89 -117.54
95% mean confidence interval for cycles %-change: -6.72% -5.63%
Cycles are helped.
total sends in shared programs: 1025285 -> 1024355 (-0.09%)
sends in affected programs: 6454 -> 5524 (-14.41%)
helped: 271 / HURT: 0
helped stats (abs) min: 2 max: 8 x̄: 3.43 x̃: 4
helped stats (rel) min: 5.71% max: 25.00% x̄: 14.98% x̃: 17.39%
95% mean confidence interval for sends value: -3.57 -3.29
95% mean confidence interval for sends %-change: -15.42% -14.54%
Sends are helped.
According to Felix DeGrood, this results in a 10% improvement in
the draw call time for certain draw calls from Strange Brigade.
Reviewed-by: Caio Oliveira <caio.oliveira@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/17944>
VS, TCS, TES, and GS threads must end with a URB write message with the
EOT (end of thread) bit set. For VS and TES, we shadow output variables
with temporaries and perform all stores at the end of the shader, giving
us an existing message to do the EOT.
In tessellation control shaders, we don't defer output stores until the
end of the thread like we do for vertex or evaluation shaders. We just
process store_output and store_per_vertex_output intrinsics where they
occur, which may be in control flow. So we can't guarantee that there's
a URB write being at the end of the shader.
Traditionally, we've just emitted a separate URB write to finish TCS
threads, doing a writemasked write to an single patch header DWord.
On Broadwell, we need to set a "TR DS Cache Disable" bit, so this is
a convenient spot to do so. But on other platforms, there's no such
field, and this write is purely wasteful.
Insetad of emitting a separate write, we can just look for an existing
URB write at the end of the program and tag that with EOT, if possible.
We already had code to do this for geometry shaders, so just lift it
into a helper function and reuse it.
No changes in shader-db.
Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Reviewed-by: Caio Oliveira <caio.oliveira@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/17944>
It's very unfortunate that we have the RT scratch being conflated with
the usual scratch. In our implementation those are 2 different buffers.
The usual scratch access are done through the scratch surface state
(delivered through thread payload), while RT scratch (which outlives
thread dispatch with shader calls) is its own buffer.
So checking the NIR scratch size makes no sense as we can have normal
scratch accesses completely unrelated to RT scratch accesses.
This change switches the validation by looking at whether the scratch
base pointer intrinsic is being used (which is what we use/abuse to
implement RT scratch).
Signed-off-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Fixes: c78be5da30 ("intel/fs: lower ray query intrinsics")
Reviewed-by: Ivan Briano <ivan.briano@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/17396>
It's already called in brw_postprocess_nir and calling it the second time
actually breaks shading rate.
Initially, when I added this call here in 9acb30c8c4, I was testing it
on an internal tree, which didn't have brw_nir_lower_shading_rate_output call
in brw_postprocess_nir.
Fixes: 9acb30c8c4 ("intel/compiler: implement primitive shading rate for mesh")
Reviewed-by: Caio Oliveira <caio.oliveira@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/18702>
During the lower_regioning() optimization, required_exec_type() is
returning BRW_REGISTER_TYPE_UQ type when processing
SHADER_OPCODE_SHUFFLE instructions of type BRW_REGISTER_TYPE_DF but
MTL has float64 support but lacks int64 support causing shader
compilation to fail.
To fix that we could make required_exec_type() return
BRW_REGISTER_TYPE_DF in such case but SHADER_OPCODE_SHUFFLE virtual
instruction runs in the integer pipeline(inferred_exec_pipe()).
So here replacing the has_64bit check by has_64bit_int, this will
properly handle older and newer cases making this function return
BRW_REGISTER_TYPE_UD.
Then lower_exec_type() will take care to generate 2 32bits operations
to accomplish the same.
While at it also dropping the 'devinfo->verx10 == 70' check as
GFX7_FEATURES fall into the same category as MTL, has float64 but no
int64 support.
Fixes at least this crucible tests:
func.uniform-subgroup.exclusive.fadd64.q0
func.uniform-subgroup.exclusive.fmin64.q0
func.uniform-subgroup.exclusive.fmax64.q0
Reviewed-by: Francisco Jerez <currojerez@riseup.net>
Reviewed-by: Matt Turner <mattst88@gmail.com>
Signed-off-by: José Roberto de Souza <jose.souza@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/18577>
