Per https://gitlab.freedesktop.org/mesa/mesa/-/issues/5178#note_1019666,
the assumption fundamental to this optimization is false. Section
2.4.1 (Float to Integer) of Ivy Bridge PRMs describes the situation.
The wording of the section is somewhat confusing (because it doesn't
clearly delineate between signed and unsigned integers), but the last
two rows of the table make it clear that F->UD conversion clamps
negative float values to 0.
All other hardware mentioned in that thread seems to behave the same
way.
The real problem is that, with hardware that behaves in this ways,
converting f2u(2147483648.0) to f2i(2147483648.0) changes the bit pattern
that would be produced from 0x80000000 to 0x7fffffff.
This reverts commit ad05920258.
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/12297>
If "a" is a multiple of "b", then the result would have been "b" instead
of 0.
No fossil-db changes.
Signed-off-by: Rhys Perry <pendingchaos02@gmail.com>
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
Fixes: 0ef5f3552f ("nir: add strength reduction pattern for imod/irem with pow2 divisor.")
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/12039>
This patch also adds has_iadd3 bit to give more control if backend
supports ternary add instruction or not.
v2:
- Add patterns in late optimization (Connor Abbott)
Suggested-by: Alyssa/Jason
Signed-off-by: Sagar Ghuge <sagar.ghuge@intel.com>
Reviewed-by: Alyssa Rosenzweig <alyssa@collabora.com>
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/11596>
Found in some sottr shaders (originally iand(ishr(a, 16), 0xffff))
Signed-off-by: Rhys Perry <pendingchaos02@gmail.com>
Reviewed-by: Timur Kristóf <timur.kristof@gmail.com>
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/3151>
The flt version could have been added in 56e21647e2, but our
collective understanding of NaN and comparisons was poor in 2015. The
new "is_a_number" predicate makes the others possible.
All of the helped shaders in shader-db are either from Mad Max or Skia.
Some of the Skia shaders just get decimated by this change:
instructions helped: shaders/skia/580-4.shader_test FS SIMD8: 81 -> 29 (-64.20%) (scheduled: top-down)
I looked at a couple of those shaders, and they had sequences like:
vec1 32 ssa_44 = flt32 ssa_32, ssa_32
vec1 32 ssa_45 = b32csel ssa_44, ssa_43, ssa_0
vec1 32 ssa_46 = fge32 ssa_32, ssa_32
vec1 32 ssa_47 = b32csel ssa_46, ssa_0, ssa_45
vec1 32 ssa_48 = iand ssa_46, ssa_44
vec1 32 ssa_49 = b32csel ssa_48, ssa_43, ssa_0
ssa_44 is replaced with False. Then ssa_47 selects between ssa_0 and
ssa_0, so ssa_47 and ssa_46 are eliminated. ssa_48 is (False && don't
care), so ssa_48 and ssa_49 are eliminated. After that, many
calculations now involve constants of zero, so they are optimized down
too. So it continues until there's not much left!
Reviewed-by: Rhys Perry <pendingchaos02@gmail.com>
All Intel platforms had similar results. (Tiger Lake shown)
total instructions in shared programs: 21072238 -> 21071386 (<.01%)
instructions in affected programs: 33722 -> 32870 (-2.53%)
helped: 146
HURT: 1
helped stats (abs) min: 1 max: 62 x̄: 5.84 x̃: 2
helped stats (rel) min: 0.19% max: 62.35% x̄: 4.09% x̃: 1.07%
HURT stats (abs) min: 1 max: 1 x̄: 1.00 x̃: 1
HURT stats (rel) min: 0.20% max: 0.20% x̄: 0.20% x̃: 0.20%
95% mean confidence interval for instructions value: -7.94 -3.65
95% mean confidence interval for instructions %-change: -5.87% -2.25%
Instructions are helped.
total cycles in shared programs: 856203326 -> 856192238 (<.01%)
cycles in affected programs: 749966 -> 738878 (-1.48%)
helped: 148
HURT: 0
helped stats (abs) min: 1 max: 1226 x̄: 74.92 x̃: 18
helped stats (rel) min: 0.07% max: 49.70% x̄: 2.69% x̃: 0.46%
95% mean confidence interval for cycles value: -104.82 -45.02
95% mean confidence interval for cycles %-change: -4.01% -1.37%
Cycles are helped.
LOST: 4
GAINED: 0
Fossil-db results:
Tiger Lake
Instructions in all programs: 160915223 -> 160898354 (-0.0%)
SENDs in all programs: 6812780 -> 6812780 (+0.0%)
Loops in all programs: 38340 -> 38340 (+0.0%)
Cycles in all programs: 7434144207 -> 7433978462 (-0.0%)
Spills in all programs: 192582 -> 192582 (+0.0%)
Fills in all programs: 304537 -> 304537 (+0.0%)
Ice Lake
Instructions in all programs: 145296298 -> 145279531 (-0.0%)
SENDs in all programs: 6863692 -> 6863692 (+0.0%)
Loops in all programs: 38334 -> 38334 (+0.0%)
Cycles in all programs: 8800257014 -> 8800088384 (-0.0%)
Spills in all programs: 216880 -> 216880 (+0.0%)
Fills in all programs: 334248 -> 334248 (+0.0%)
Skylake
Instructions in all programs: 135891664 -> 135874910 (-0.0%)
SENDs in all programs: 6802946 -> 6802946 (+0.0%)
Loops in all programs: 38331 -> 38331 (+0.0%)
Cycles in all programs: 8444273433 -> 8444130932 (-0.0%)
Spills in all programs: 194839 -> 194839 (+0.0%)
Fills in all programs: 301114 -> 301114 (+0.0%)
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/10012>
If the values are known to be numbers, the the replacements are exact.
This is only applied to the patterns with constants. Constants should
always be numbers, and shaders with NaN constants should be handled in a
different way.
No shader-db or fossil-db changes on any Intel platform. The intention
is to make these patterns more future proof.
Reviewed-by: Rhys Perry <pendingchaos02@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/10012>
Reviewed-by: Rhys Perry <pendingchaos02@gmail.com>
All Haswell and later Intel platforms had similar results. (Tiger Lake shown)
total instructions in shared programs: 21049056 -> 21048939 (<.01%)
instructions in affected programs: 4716 -> 4599 (-2.48%)
helped: 39
HURT: 0
helped stats (abs) min: 1 max: 6 x̄: 3.00 x̃: 3
helped stats (rel) min: 0.99% max: 5.43% x̄: 2.80% x̃: 2.51%
95% mean confidence interval for instructions value: -3.46 -2.54
95% mean confidence interval for instructions %-change: -3.22% -2.38%
Instructions are helped.
total cycles in shared programs: 855141411 -> 855141159 (<.01%)
cycles in affected programs: 54491 -> 54239 (-0.46%)
helped: 28
HURT: 5
helped stats (abs) min: 2 max: 34 x̄: 12.82 x̃: 12
helped stats (rel) min: 0.06% max: 2.73% x̄: 0.94% x̃: 0.75%
HURT stats (abs) min: 2 max: 52 x̄: 21.40 x̃: 6
HURT stats (rel) min: 0.11% max: 2.46% x̄: 0.90% x̃: 0.56%
95% mean confidence interval for cycles value: -13.72 -1.55
95% mean confidence interval for cycles %-change: -1.01% -0.31%
Cycles are helped.
Tiger Lake
Instructions in all programs: 160902191 -> 160899554 (-0.0%)
SENDs in all programs: 6812435 -> 6812435 (+0.0%)
Loops in all programs: 38225 -> 38225 (+0.0%)
Cycles in all programs: 7428581420 -> 7428555881 (-0.0%)
Spills in all programs: 192582 -> 192582 (+0.0%)
Fills in all programs: 304539 -> 304539 (+0.0%)
A lot of fragment shaders in Shadow of the Tomb Raider were helped, and
a bunch of vertex shaders in Octopath Traveler were hurt.
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/10012>
It seems worth the small amount of damage to give an extra cushion of
not having to debug problems later.
Reviewed-by: Rhys Perry <pendingchaos02@gmail.com>
All Intel platforms had similar results. (Tiger Lake shown)
total instructions in shared programs: 21043197 -> 21043359 (<.01%)
instructions in affected programs: 4409 -> 4571 (3.67%)
helped: 0
HURT: 25
HURT stats (abs) min: 1 max: 16 x̄: 6.48 x̃: 5
HURT stats (rel) min: 0.39% max: 15.38% x̄: 4.59% x̃: 4.40%
95% mean confidence interval for instructions value: 4.37 8.59
95% mean confidence interval for instructions %-change: 2.93% 6.26%
Instructions are HURT.
total cycles in shared programs: 856175986 -> 856176921 (<.01%)
cycles in affected programs: 58908 -> 59843 (1.59%)
helped: 0
HURT: 25
HURT stats (abs) min: 7 max: 70 x̄: 37.40 x̃: 38
HURT stats (rel) min: 0.27% max: 5.63% x̄: 1.87% x̃: 1.39%
95% mean confidence interval for cycles value: 31.11 43.69
95% mean confidence interval for cycles %-change: 1.35% 2.39%
Cycles are HURT.
No fossil-db changes on any Intel platform.
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/10012>
When most of these patterns were created, we believed, incorrectly, that
fsat(NaN) was NaN. We have since realized that fsat(NaN) is zero.
Originally, this changed the patterns to use is_a_number. This didn't
help any shaders, so it's easier to just drop the optimizations.
This commit crossed paths with 4c3ad4d065 ("nir/algebraic: mark more
optimization with fsat(NaN) as inexact") and bc123c396a
("nir/algebraic: mark some optimizations with fsat(NaN) as inexact").
Given that these don't impact very many shaders, it seems safer to just
remove them.
As discussed in
https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/8716, I tried
modifying these patterns to use !(b cmp a). Unfortunately, on Intel
GPUs, the results were much worse than just removing the patterns
altogether.
Some other related patterns will be addressed in later commits.
There are still a number of patterns that use the identity fsat(1-X) ==
1 - fsat(X). If X is NaN, the former is zero while the latter is 1.0.
I haven't evaluted these patterns yet. If changes are needed in these
patterns, it should be a separate commit anyway.
v2: Replace arrow `=>` with `->` in comments because the `=>` looks a
lot like `<=` comparison. Suggested by Rhys.
Fixes: 92b75c126b ("nir/algebraic: Replace checks that a value is between (or not) [0, 1]")
Fixes: a7f0c57673 ("nir/algebraic: Eliminate useless fsat() on operand of comparison w/value in (0, 1)")
Reviewed-by: Rhys Perry <pendingchaos02@gmail.com>
All Intel hardware had similar results. (Ice Lake shown)
total instructions in shared programs: 20029060 -> 20029670 (<.01%)
instructions in affected programs: 69236 -> 69846 (0.88%)
helped: 0
HURT: 263
HURT stats (abs) min: 1 max: 20 x̄: 2.32 x̃: 1
HURT stats (rel) min: 0.30% max: 11.11% x̄: 1.35% x̃: 0.98%
95% mean confidence interval for instructions value: 1.86 2.78
95% mean confidence interval for instructions %-change: 1.18% 1.52%
Instructions are HURT.
total cycles in shared programs: 979821278 -> 979834425 (<.01%)
cycles in affected programs: 1476848 -> 1489995 (0.89%)
helped: 49
HURT: 204
helped stats (abs) min: 1 max: 812 x̄: 102.31 x̃: 20
helped stats (rel) min: 0.01% max: 21.43% x̄: 2.23% x̃: 0.52%
HURT stats (abs) min: 2 max: 2600 x̄: 89.02 x̃: 16
HURT stats (rel) min: 0.04% max: 27.27% x̄: 1.49% x̃: 0.72%
95% mean confidence interval for cycles value: 13.18 90.75
95% mean confidence interval for cycles %-change: 0.29% 1.25%
Cycles are HURT.
No fossil-db changes.
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/10012>
These are equivalent to the 32bit opcodes if there are no more efficient
24bit opcodes available, but inputs are guaranteed to already be 24bit,
so the 24bit opcodes can be used instead if they exist and are efficient.
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
Reviewed-by: Karol Herbst <kherbst@redhat.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/10549>
For unsigned comparisons with zero these ops can be eliminated.
v2: Add comparison optimizations with -1 (Rhys Perry)
Signed-off-by: Gert Wollny <gert.wollny@collabora.com>
Reviewed-by: Eric Anholt <eric@anholt.net> (v1)
Reviewed-by: Rhys Perry <pendingchaos02@gmail.com>
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/10583>
HLSL doesn't support bitcasting a 64bit integer to a double. DXIL
doesn't have generic pack/unpack instructions, so we lower those to
integer bitwise ops. As a result, NIR generic double pack/unpack would
require our backend to emit a bitcast to get a double, but we want
to match HLSL semantics and emit MakeDouble/SplitDouble.
Adding a dedicated opcode for double pack/unpack allows us to add a
pass to emit that instead, which lets our backend emit the right
instruction to pack and unpack doubles.
Acked-by: Jason Ekstrand <jason@jlekstrand.net>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/10063>
Some backends, like r600 support a fused version of int and float compare
against zero and and csel. Adding these opcodes here makes it possible to
optimize this in nir.
v2: Add rules for float compare + csel
Signed-off-by: Gert Wollny <gert.wollny@collabora.com>
Reviewed-by: Kristian H. Kristensen <hoegsberg@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/9452>
Some hardware supports a version of find_msb where the bits are counted
starting at the high bit, and this needs some lowering to obtain the
value that is expected by *find_msb
Signed-off-by: Gert Wollny <gert.wollny@collabora.com>
Reviewed-by: Kristian H. Kristensen <hoegsberg@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/9452>
There are patterns that will re-write the fmin or fmax part into a form
that other patterns will gradually convert to the same ior or iand. For
example,
fmax(b2f(a), b2f(b)) != 0
b2f(a || b) != 0
a || b
No shader-db or fossil-db changes on any Intel platform.
Reviewed-by: Matt Turner <mattst88@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/9122>
fmin(-A, -B) is -fmax(A, B), and fmax(-A, -B) is -fmin(A, B). Therefore
the logic joining A and B should toggle between ior and iand for the
negated versions.
At the very least, a shader from Euro Truck Simulator 2 in shader-db is
affected by this. The KIL instruction in the (ARB assembly) shader ends
up with the wrong logic. This is _probably_ the source of
https://gitlab.freedesktop.org/mesa/mesa/-/issues/1346.
That said, the issue mentions that Mesa 18.0.5 works, but commit
68420d8322 ("nir: Simplify min and max of b2f") was added in 17.3.
Moreover, I was not able to reproduce the error in the ETS2 shader from
shader-db from any Mesa commit near the time the original fd.o bugzilla
was submitted (December 2018). 🤷
In fact, the current error in that shader starts with 9167324a86
("nir/algebraic: Mark some logic-joined comparison reductions as
exact"). That's a bit of a red herring as 9167324a86 just sets off a
chain of replacements that eventually leads to the incorrect min/max of
b2f patterns fixed by this commit.
The other affected shaders in the shader-db results are from Cargo
Commander. These are also ARB assembly shaders.
I think any ARB assembly shader that uses the pattern
SLT r0, ...;
...
KIL -r0;
will suffer from issues related to this.
This change fixes the piglit
tests/spec/arb_fragment_program/kil-of-slt.shader_test test added in
https://gitlab.freedesktop.org/mesa/piglit/-/merge_requests/454.
shader-db results:
All Gen6+ platforms had similar result. (Ice Lake shown)
total instructions in shared programs: 20034604 -> 20034486 (<.01%)
instructions in affected programs: 3885 -> 3767 (-3.04%)
helped: 47
HURT: 2
helped stats (abs) min: 2 max: 4 x̄: 2.64 x̃: 2
helped stats (rel) min: 2.33% max: 8.33% x̄: 3.48% x̃: 3.39%
HURT stats (abs) min: 3 max: 3 x̄: 3.00 x̃: 3
HURT stats (rel) min: 13.64% max: 16.67% x̄: 15.15% x̃: 15.15%
95% mean confidence interval for instructions value: -2.83 -1.99
95% mean confidence interval for instructions %-change: -3.84% -1.60%
Instructions are helped.
total cycles in shared programs: 979881379 -> 979879406 (<.01%)
cycles in affected programs: 119873 -> 117900 (-1.65%)
helped: 46
HURT: 3
helped stats (abs) min: 10 max: 756 x̄: 45.41 x̃: 26
helped stats (rel) min: 0.53% max: 19.72% x̄: 1.67% x̃: 1.26%
HURT stats (abs) min: 28 max: 56 x̄: 38.67 x̃: 32
HURT stats (rel) min: 1.44% max: 3.54% x̄: 2.75% x̃: 3.27%
95% mean confidence interval for cycles value: -70.83 -9.70
95% mean confidence interval for cycles %-change: -2.23% -0.57%
Cycles are helped.
Iron Lake and GM45 had similar results. (Iron Lake shown)
total instructions in shared programs: 8115098 -> 8115076 (<.01%)
instructions in affected programs: 2592 -> 2570 (-0.85%)
helped: 32
HURT: 2
helped stats (abs) min: 1 max: 1 x̄: 1.00 x̃: 1
helped stats (rel) min: 0.88% max: 2.70% x̄: 1.35% x̃: 1.31%
HURT stats (abs) min: 5 max: 5 x̄: 5.00 x̃: 5
HURT stats (rel) min: 17.24% max: 18.52% x̄: 17.88% x̃: 17.88%
95% mean confidence interval for instructions value: -1.15 -0.15
95% mean confidence interval for instructions %-change: -1.83% 1.39%
Inconclusive result (%-change mean confidence interval includes 0).
total cycles in shared programs: 238189718 -> 238189802 (<.01%)
cycles in affected programs: 75076 -> 75160 (0.11%)
helped: 3
HURT: 31
helped stats (abs) min: 2 max: 130 x̄: 44.67 x̃: 2
helped stats (rel) min: 0.18% max: 5.70% x̄: 2.02% x̃: 0.19%
HURT stats (abs) min: 2 max: 70 x̄: 7.03 x̃: 4
HURT stats (rel) min: 0.07% max: 6.41% x̄: 0.53% x̃: 0.15%
95% mean confidence interval for cycles value: -7.27 12.21
95% mean confidence interval for cycles %-change: -0.33% 0.94%
Inconclusive result (value mean confidence interval includes 0).
No fossil-db changes on any Intel platform.
Fixes: 68420d8322 ("nir: Simplify min and max of b2f")
Closes: #1346
Reviewed-by: Matt Turner <mattst88@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/9122>
There are a bunch of cases where we can pretty quickly determine that
the high bits don't matter. In these cases, delete the casts.
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/8872>
The base mask previously used was 0xffffffff. This is not correct (but
should still work) for 16-bit and 8-bit values, but it means the high
32-bits of 64-bit values will get chopped off.
Instead of just restricting the pattern to 32-bits (as was done before
00b28a50b2), this extends the optimization in two ways:
1. Make it correct for other bit sizes.
2. Make it work for arbitrary shift counts.
This has the added benefit of reducing the number of patterns actually
added (7 previously, 4 now).
The "Reassociate for improved CSE" part is just reverted to its
pre-00b28a50b2c behavior. I doubt that pattern is likely to have much
impact outside 32-bits.
This change fixes the piglit tests
tests/spec/arb_gpu_shader_int64/fs-shl-of-shr-int64.shader_test and
tests/spec/arb_gpu_shader_int64/fs-iand-of-iadd-int64.shader_test.
All of the shaders helped in shader-db are vertex shaders on platforms
with vector-oriented vertex processing. The shaders contain ((x >> 16)
<< 16). These platforms set lower_extract_word, so the optimization
that transforms (x >> 16) to extract_u16 doesn't trigger. With only ~60
shaders involved, I didn't bother trying to add extract_XYZ versions of
these patterns to try to get those cases.
Fixes: 00b28a50b2 ("nir/algebraic: trivially enable existing 32-bit patterns for all bit sizes")
Reviewed-by: Rhys Perry <pendingchaos02@gmail.com>
Haswell and earlier Intel GPUs had simlar results. (Haswell shown)
total instructions in shared programs: 16397554 -> 16397496 (<.01%)
instructions in affected programs: 7961 -> 7903 (-0.73%)
helped: 58
HURT: 0
helped stats (abs) min: 1 max: 1 x̄: 1.00 x̃: 1
helped stats (rel) min: 0.36% max: 1.89% x̄: 0.99% x̃: 0.78%
95% mean confidence interval for instructions value: -1.00 -1.00
95% mean confidence interval for instructions %-change: -1.13% -0.85%
Instructions are helped.
total cycles in shared programs: 1035483770 -> 1035483504 (<.01%)
cycles in affected programs: 75922 -> 75656 (-0.35%)
helped: 44
HURT: 2
helped stats (abs) min: 2 max: 12 x̄: 6.14 x̃: 2
helped stats (rel) min: 0.05% max: 1.67% x̄: 0.87% x̃: 0.72%
HURT stats (abs) min: 2 max: 2 x̄: 2.00 x̃: 2
HURT stats (rel) min: 0.06% max: 0.06% x̄: 0.06% x̃: 0.06%
95% mean confidence interval for cycles value: -7.28 -4.29
95% mean confidence interval for cycles %-change: -1.03% -0.63%
Cycles are helped.
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/8852>
This patch also replaces lower_negate with lower_ineg / lower_fneg.
The fneg semantics have been clarified as of Version 1.5, Revision 1
of the SPIR-V specification, which means that the previous lowering
to fsub is not a viable solution anymore, and is replaced with
lowering to fmul(x, -1.0).
Reviewed-by: Erik Faye-Lund <erik.faye-lund@collabora.com>
Reviewed-by: Eric Anholt <eric@anholt.net>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/6597>
If multiple rules could match, the rule that appears first in the file
is used.
Only Tiger Lake and Ice Lake are affected. Other platforms either have
a LRP instruction or can't run any shaders from shader-db that would
benefit.
v2: Fix issues created when this commit was rebased on top of
3c8934a644 ("nir/algebraic: add flrp patterns for 16 and 64 bits").
Noticed by Caio.
Tiger Lake and Ice Lake had similar results.
total instructions in shared programs: 20908672 -> 20908661 (<.01%)
instructions in affected programs: 419 -> 408 (-2.63%)
helped: 5
HURT: 0
helped stats (abs) min: 1 max: 3 x̄: 2.20 x̃: 3
helped stats (rel) min: 1.85% max: 3.19% x̄: 2.49% x̃: 2.65%
95% mean confidence interval for instructions value: -3.56 -0.84
95% mean confidence interval for instructions %-change: -3.24% -1.73%
Instructions are helped.
total cycles in shared programs: 473513940 -> 473513793 (<.01%)
cycles in affected programs: 7176 -> 7029 (-2.05%)
helped: 12
HURT: 0
helped stats (abs) min: 5 max: 22 x̄: 12.25 x̃: 12
helped stats (rel) min: 0.84% max: 3.24% x̄: 2.09% x̃: 1.80%
95% mean confidence interval for cycles value: -15.43 -9.07
95% mean confidence interval for cycles %-change: -2.57% -1.61%
Cycles are helped.
Reviewed-by: Caio Marcelo de Oliveira Filho <caio.oliveira@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/6358>
This prevents other transformations from converting them to 'a != 0'.
For example, both of these transformations can do this:
(('~flt', 0.0, ('fabs', a)), ('fne', a, 0.0)),
(('~flt', ('fneg', ('fabs', a)), 0.0), ('fne', a, 0.0)),
Both fsign(fabs(NaN)) and fsign(fneg(fabs(NaN))) should produce zero,
but, since 'NaN != 0.0' is true, cascading these transformations could
cause them to generate 1.0 or -1.0 respecively.
No shader-db or fossil-db changes on any Intel platform.
Reviewed-by: Caio Marcelo de Oliveira Filho <caio.oliveira@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/6358>
No shader-db or fossil-db changes on any Intel platform.
v2: Add a coding line to fix SCons build problems caused by the ±
character.
Fixes: 25bfba3335 ("nir/algebraic: Recognize open-coded copysign(1.0, a)")
Reviewed-by: Caio Marcelo de Oliveira Filho <caio.oliveira@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/6358>
This prevents some fossil-db regressions in "spir-v: Mark floating point
comparisons exact".
v2: Note that the patterns and replacements produce the same value when
isnan(b). Suggested by Caio.
v3: Use C99 isfinite() instead of (obsolete) BSD finite(). Fixes
various Windows builds.
No fossil-db changes on any Inetl platform, Vega, or Polaris10.
All Intel platforms had similar results. (Tiger Lake shown)
total instructions in shared programs: 20908670 -> 20908672 (<.01%)
instructions in affected programs: 69 -> 71 (2.90%)
helped: 0
HURT: 1
total cycles in shared programs: 473515288 -> 473513940 (<.01%)
cycles in affected programs: 4942 -> 3594 (-27.28%)
helped: 2
HURT: 0
Reviewed-by: Caio Marcelo de Oliveira Filho <caio.oliveira@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/6358>
This also prevents some fossil-db regressions in "spir-v: Mark floating
point comparisons exact".
v2: Mark the fmin / fmax in the replacement exact to prevent other
optimizations from ruining the NaN-clensing property of the fmin / fmax.
Suggested by Rhys. Don't assume that constants are not NaN because some
components of a vector might be NaN while others are numbers. Noticed
by Rhys. This causes ~8 more shaders in Age of Wonders III (dxvk) to
regress on cycles (not instructions) by less than 1% when "spir-v: Mark
floating point comparisons exact" is applied. This difference is too
small to care.
All Intel platforms had similar results. (Tiger Lake shown)
total instructions in shared programs: 20908668 -> 20908670 (<.01%)
instructions in affected programs: 9196 -> 9198 (0.02%)
helped: 10
HURT: 5
helped stats (abs) min: 1 max: 2 x̄: 1.40 x̃: 1
helped stats (rel) min: 0.02% max: 5.41% x̄: 2.20% x̃: 2.16%
HURT stats (abs) min: 2 max: 6 x̄: 3.20 x̃: 3
HURT stats (rel) min: 2.44% max: 16.67% x̄: 9.39% x̃: 12.50%
95% mean confidence interval for instructions value: -1.22 1.49
95% mean confidence interval for instructions %-change: -2.08% 5.41%
Inconclusive result (value mean confidence interval includes 0).
total cycles in shared programs: 473515330 -> 473515288 (<.01%)
cycles in affected programs: 67146 -> 67104 (-0.06%)
helped: 10
HURT: 7
helped stats (abs) min: 1 max: 36 x̄: 15.90 x̃: 17
helped stats (rel) min: 0.01% max: 1.29% x̄: 0.66% x̃: 0.89%
HURT stats (abs) min: 1 max: 48 x̄: 16.71 x̃: 4
HURT stats (rel) min: 0.08% max: 1.94% x̄: 0.87% x̃: 0.19%
95% mean confidence interval for cycles value: -13.88 8.94
95% mean confidence interval for cycles %-change: -0.56% 0.49%
Inconclusive result (value mean confidence interval includes 0).
Reviewed-by: Caio Marcelo de Oliveira Filho <caio.oliveira@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/6358>
The reordered are automatically considered by nir_algebraic rules for
commutative instructions.
No shader-db or fossil-db changes on any Intel platform.
Reviewed-by: Caio Marcelo de Oliveira Filho <caio.oliveira@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/6358>
I originally noticed that 3b30814791 ("nir/algebraic: Optimize 1-bit
Booleans") caused this pattern no longer be matched by incorrectly
replacing b@32 with b@1. Making that correct had no effect on
shader-db. When this pattern originally was added, it only affected 4
shaders, so it's not worth the effort to debug further.
This reverts commit f50400cc80.
Reviewed-by: Caio Marcelo de Oliveira Filho <caio.oliveira@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/6358>
The original comment was a little terse and a little incorrect. The
rearrangements are fine w.r.t. NaN. However, they produce incorrect
results if one operand is +Inf and the other is -Inf.
A later commit, "nir/algebraic: Add some compare-with-zero optimizations
that are exact", will add some more patterns here. It may be reasonable
to squash this commit (forward) into that commit.
v2: Fix some incorrect comparisons operators in the comment (<= vs >=).
Add commentary that subtraction works like addition w.r.t. NaN. Both
noticed / suggested by Caio.
Reviewed-by: Caio Marcelo de Oliveira Filho <caio.oliveira@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/6358>
Eric Engestrom
Ian Romanick
Rhys Perry
Dave Airlie
Sagar Ghuge
Jason Ekstrand
Jesse Natalie
Gert Wollny
Timur Kristóf
Timothy Arceri
Jason Ekstrand
Samuel Pitoiset
Daniel Schürmann