There are a number of instances of the dead code elimination pass that
could reduce the count. For some reason this also seems to affect
register allocation itself.
Signed-off-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Cc: mesa-stable
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Francisco Jerez <currojerez@riseup.net>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/21853>
Most tools looking at shader stats assume that there is only a single
resulting binary shader out of a single input. On Intel HW this is not
always the case. So having a statistic on each variant that reports
the maximum dispatch width helps showing improvement on a single
shader in terms of how large we manage to compile it.
For shaders that can be compiled in multiple SIMD width (like fragment
shaders), this will report the maximum dispatch width in the
statistics of each variants.
Signed-off-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Reviewed-by: Sagar Ghuge <sagar.ghuge@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/22014>
For instance, to load uniform data with the LSC we usually rely on
tranpose messages which have to execute in SIMD1. Those end up being
considered as partial writes so within loops their life span spread to
the whole loop, increasing register pressure.
Signed-off-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Cc: mesa-stable
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/21867>
Wa_14017989577 is a clone of Wa_14015360517, which applies to several
platforms beyond INTEL_PLATFORM_DG2_G10.
Update references to Wa_14017989577, and use the generated workaround
helper to ensure application to the proper platforms.
Reviewed-by: Tapani Pälli <tapani.palli@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/21744>
This allows us to communicate to the back-end that we don't actually
know if the framebuffer is multisampled or not. No drivers set anything
but ALWAYS/NEVER and we still have a few ALWAYS/NEVER assumptions but
those should be asserted.
Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/21094>
This allows for the possibility that we may not know at compile time if
sample shading is enabled through the API. While we're here, also
document exactly what this bit means so we don't confuse ourselves.
v2: Fixup coarse pixel values (Lionel)
Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/21094>
Whenever one of them is BRW_SOMETIMES, we depend on dynamic flag pushed
in as a push constant. In this case, we have to often have to do the
calculation both ways and SEL the result. It's a bit more code but
decouples MSAA from the shader key.
Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/21094>
We can lower FS_OPCODE_UNIFORM_PULL_CONSTANT_LOAD into other more
generic sends and drop this internal opcode.
The idea behind this change is to allow bindless surfaces to be used
for UBO pulls and why it's interesting to be able to reuse
setup_surface_descriptors(). But that will come in a later change.
No shader-db changes on TGL & DG2.
Signed-off-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/20416>
These are handled identically in almost all cases. There is one place
in the legacy surface lowering that was obtaining the bitsize from the
opcode, but the LSC-based lowering uses (type_sz(inst->dst.type) * 8)
for that and works just fine. If we just do that in the legacy lowering
too, then we don't need this plethora of opcodes.
Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Reviewed-by: Rohan Garg <rohan.garg@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/20604>
The only reason for the separate opcode was because of the overlapping
BRW_AOP_* enums, making it impossible to tell whether a particular AOP
was the integer or float operation. Now that we use the lsc_opcode
enums, we can just have the legacy lowering inspect the opcode and
select the right descriptor. No need for a separate opcode.
Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Reviewed-by: Rohan Garg <rohan.garg@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/20604>
There are a number of places that need to know how many operands an LSC
atomic takes (0 for inc/dec, 1 for most things, 2 for cmpxchg). We can
add a helper for that and eliminate some code (with more to come).
Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Reviewed-by: Rohan Garg <rohan.garg@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/20604>
This gets our logical atomic messages using the lsc_opcode enum rather
than the legacy BRW_AOP_* defines. We have to translate one way or
another, and using the modern set makes sense going forward.
One advantage is that the lsc_opcode encoding has opcodes for both
integer and floating point atomics in the same enum, whereas the legacy
encoding used overlapping values (BRW_AOP_AND == 1 == BRW_AOP_FMAX),
which made it impossible to handle both sensibly in common code.
Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Reviewed-by: Rohan Garg <rohan.garg@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/20604>
This enabled SIMD32 in blorp shaders and seems to be give a small FPS
bump when using a DG2 GPU as secondary (requires copies to linear
buffers to exchange with main GPU).
Signed-off-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Acked-by: Matt Turner <mattst88@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/19341>
The first instruction of any kernel should have non-zero emask. This
restriction needs to be obeyed to avoid GPU hangs.
Patch adds a function to insert dummy mov as first instruction
to make sure this requirement is fulfilled.
Signed-off-by: Tapani Pälli <tapani.palli@intel.com>
Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Cc: mesa-stable
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/20194>
The parameter `nr` is currenlty an `int` but it only gets assigned to an
`unsigned int`. Make it clear in the function signature what's actually
required.
Reviewed-by: Emma Anholt <emma@anholt.net>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/19423>
GCC 12.2.0 warns:
../src/intel/compiler/brw_fs.cpp: In member function ‘bool fs_visitor::
split_virtual_grfs()’:
../src/intel/compiler/brw_fs.cpp:2199:10: warning: ‘void* memset(void*, int,
size_t)’ specified size between 18446744071562067968 and 18446744073709551615
exceeds maximum object size 9223372036854775807 [-Wstringop-overflow=]
2199 | memset(vgrf_has_split, 0, num_vars * sizeof(*vgrf_has_split));
`num_vars` is an `int` but gets assigned the value of `this->alloc.count`,
which is an `unsigned int`. Thus, `num_vars` will be negative if
`this->alloc.count` is larger than int max value. Converting that negative
`int` to a `size_t`, which `memset` expects, then blows it up to a huge
positive value.
Simply turning `num_vars` into an `unsigned int` would be enough to fix this
specific problem, but there are many other instances where an `unsigned int`
gets assigned to an `int` for no good reason in this function. Some of which
the compiler warns about now, some of which it doesn't warn about.
This turns all variables in `fs_visitor::split_virtual_grfs`, which should
reasonably be unsigned, into `unsigned int`s. While at it, a few now pointless
casts are removed.
Reviewed-by: Emma Anholt <emma@anholt.net>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/19423>
The initial implementation is a pretty big hammer. Implement the HW
recommendation to minimize cases in which we need a fence.
This improves by 10FPS on some of the Sascha Willems RT demos.
Signed-off-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Fixes: 6031ad4bf6 ("intel/fs: Add Wa_22013689345")
Reviewed-by: Francisco Jerez <currojerez@riseup.net>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/19322>
We still update the cs_prog_data, but don't rely on it for this state anymore.
This will allow use the SIMD selector with shaders that don't use cs_prog_data.
Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Reviewed-by: Ivan Briano <ivan.briano@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/19601>
This is a preparation to decouple the storage of what SIMDs
compiled/spilled from the cs_prog_data. This will allow reuse
of SIMD selection code by Bindless Shaders.
And since we have a struct now, move the error array there so
reduce the boilerplate of the users.
Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Reviewed-by: Ivan Briano <ivan.briano@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/19601>
Many Intel platforms can only perform 32x16 bit multiplication. The
straightforward way to implement 32x32 bit multiplications is by
splitting one of the operands into high and low parts called H and L,
repsectively. The full multiplication can be implemented as:
((A * H) << 16) + (A * L)
On Intel platforms, special register accesses can be used to eliminate
the shift operation. This results in three instructions and a temporary
register for most values.
If H or L is 1, then one (or both) of the multiplications will later be
eliminated. On some platforms it may be possible to eliminate the
multiplication when H is 256.
If L is zero (note that H cannot be zero), one of the multiplications
will also be eliminated.
Instead of splitting the operand into high and low parts, it may
possible to factor the operand into two 16-bit factors X and Y. The
original multiplication can be replaced with (A * (X * Y)) = ((A * X) *
Y). This requires two instructions without a temporary register.
I may have gone a bit overboard with optimizing the factorization
routine. It was a fun brainteaser, and I couldn't put it down. :) On my
1.3GHz Ice Lake, a standalone test could chug through 1,000,000 randomly
selected values in about 5.7 seconds. This is about 9x the performance
of the obvious, straightforward implementation that I started with.
v2: Drop an unnecessary return. Rearrange logic slightly and rename
variables in factor_uint32 to better match the names used in the large
comment. Both suggested by Caio. Rearrange logic to avoid possibly
using `a` uninitialized. Noticed by Marcin.
v3: Use DIV_ROUND_UP instead of open coding it. Noticed by Caio.
Tiger Lake, Ice Lake, Haswell, and Ivy Bridge had similar results. (Ice Lake shown)
total instructions in shared programs: 19912558 -> 19912526 (<.01%)
instructions in affected programs: 3432 -> 3400 (-0.93%)
helped: 10 / HURT: 0
total cycles in shared programs: 856413218 -> 856412810 (<.01%)
cycles in affected programs: 122032 -> 121624 (-0.33%)
helped: 9 / HURT: 0
No shader-db changes on any other Intel platforms.
Tiger Lake and Ice Lake had similar results. (Ice Lake shown)
Instructions in all programs: 141997227 -> 141996923 (-0.0%)
Instructions helped: 71
Cycles in all programs: 9162524757 -> 9162523886 (-0.0%)
Cycles helped: 63
Cycles hurt: 5
No fossil-db changes on any other Intel platforms.
Reviewed-by: Caio Oliveira <caio.oliveira@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/17718>
The previous bounds checking would cause
mul(8) g121<1>D g120<8,8,1>D 0xec4dD
to be lowered to
mul(8) g121<1>D g120<8,8,1>D 0xec4dUW
mul(8) g41<1>D g120<8,8,1>D 0x0000UW
add(8) g121.1<2>UW g121.1<16,8,2>UW g41<16,8,2>UW
Instead of picking the bounds (and the new type) based on the old type,
pick the new type based on the value only.
This helps a few fossil-db shaders in Witcher 3 and Geekbench5. No
changes on any other Intel platforms.
Tiger Lake
Instructions in all programs: 157581069 -> 157580768 (-0.0%)
Instructions helped: 24
Cycles in all programs: 7566979620 -> 7566977172 (-0.0%)
Cycles helped: 22
Cycles hurt: 4
Ice Lake
Instructions in all programs: 141998965 -> 141998667 (-0.0%)
Instructions helped: 26
Cycles in all programs: 9162568666 -> 9162565297 (-0.0%)
Cycles helped: 24
Cycles hurt: 2
Skylake
No changes.
Reviewed-by: Caio Oliveira <caio.oliveira@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/17718>
This specialized version prints out the liveness count as well as the
maximum liveness count. It was eye opening when seeing the max
liveness jump after lowering of packing instructions which should not
have changed the count.
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>
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>
To clean up compilation warnings about unused variables
when asserts are disabled.
v2: UNUSED -> ASSERTED (Eric Engestrom)
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/19016>
Since divergence is a lot more likely in RT than compute, it makes
sense to limit ourselves to SIMD8.
The trampoline shader defaults to SIMD16 since this one is uniform.
Signed-off-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Acked-by: Caio Oliveira <caio.oliveira@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/16970>
There will be situations where we will want to use a local builder
rather than the one associated with NIR->backend translation.
Signed-off-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/16970>
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>
And run algebraic when either int64 for float64 are not supported so
those don't end up in the generated code.
Cc: mesa-stable
Signed-off-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Reviewed-by: Ivan Briano <ivan.briano@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/17396>
Move subgroup_id, that's only used by CS for verx10 < 125, as part of
the payload too -- even though is not, strictly speaking.
Note the thread execution of Task/Mesh is similar enough, so we make
their common struct inherit from cs_thread_payload.
Reviewed-by: Francisco Jerez <currojerez@riseup.net>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/18176>
