Starting with d0d039a4d3, we emit writes to the push constant chunk
of the payload to stomp out-of-bounds data to zero for Vulkan. Then, in
369eab9420, we started emitting shader preamble code for emulated
push constants on Gen12.5 parts. In either of these cases, we can run
into issues if we don't have a proper live range for some of the payload
registers where they get used for something and then smashed by our push
handling code. We've not seen many issues with this yet because it only
happens when you have dead push constants.
Fixes: d0d039a4d3 "anv: Emit pushed UBO bounds checking code..."
Fixes: 369eab9420 "intel/fs: Emit code for Gen12-HP indirect..."
Reviewed-by: Jordan Justen <jordan.l.justen@intel.com>
Reviewed-by: Caio Marcelo de Oliveira Filho <caio.oliveira@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/9501>
Previously can_do_source_mods was used to determine whether a value with
a source modifier or a value from a scalar source (e.g., a uniform)
could be copy propagated. The former is a superset of the latter, so
this always produces correct results, but it is overly restrictive. For
example, a BFI instruction can't have source modifiers, but it can have
scalar sources.
This was originally authored to prevent a small number of shader-db
regressions in a commit that marked SHR has not being able to have
source modifiers. That commit has since been dropped in favor of a
different method.
v2: Refactor register region restriction detection to a helper function.
Suggested by Jason.
No fossil-db changes on any Intel platform.
All Gen7+ platforms had similar results. (Ice Lake shown)
total instructions in shared programs: 20039111 -> 20038943 (<.01%)
instructions in affected programs: 31736 -> 31568 (-0.53%)
helped: 104
HURT: 0
helped stats (abs) min: 1 max: 9 x̄: 1.62 x̃: 1
helped stats (rel) min: 0.30% max: 0.88% x̄: 0.45% x̃: 0.42%
95% mean confidence interval for instructions value: -2.03 -1.20
95% mean confidence interval for instructions %-change: -0.47% -0.42%
Instructions are helped.
total cycles in shared programs: 980309750 -> 980308897 (<.01%)
cycles in affected programs: 591078 -> 590225 (-0.14%)
helped: 70
HURT: 26
helped stats (abs) min: 2 max: 622 x̄: 23.94 x̃: 4
helped stats (rel) min: <.01% max: 2.85% x̄: 0.33% x̃: 0.12%
HURT stats (abs) min: 2 max: 520 x̄: 31.65 x̃: 6
HURT stats (rel) min: 0.02% max: 2.45% x̄: 0.34% x̃: 0.15%
95% mean confidence interval for cycles value: -26.41 8.64
95% mean confidence interval for cycles %-change: -0.27% -0.03%
Inconclusive result (value mean confidence interval includes 0).
No shader-db changes on earlier Intel platforms.
Reviewed-by: Anuj Phogat anuj.phogat@gmail.com [v1]
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/9237>
On Intel platforms before Gen6, there is no min or max instruction.
Instead, a comparison instruction (*more on this below) and a SEL
instruction are used. Per other IEEE rules, the regular comparison
instruction, CMP, will always return false if either source is NaN. A
sequence like
cmp.l.f0.0(16) null<1>F g30<8,8,1>F g22<8,8,1>F
(+f0.0) sel(16) g8<1>F g30<8,8,1>F g22<8,8,1>F
will generate the wrong result for min if g22 is NaN. The CMP will
return false, and the SEL will pick g22.
To account for this, the hardware has a special comparison instruction
CMPN. This instruction behaves just like CMP, except if the second
source is NaN, it will return true. The intention is to use it for min
and max. This sequence will always generate the correct result:
cmpn.l.f0.0(16) null<1>F g30<8,8,1>F g22<8,8,1>F
(+f0.0) sel(16) g8<1>F g30<8,8,1>F g22<8,8,1>F
The problem is... for whatever reason, we don't emit CMPN. There was
even a comment in lower_minmax that calls out this very issue! The bug
is actually older than the "Fixes" below even implies. That's just when
the comment was added. That we know of, we never observed a failure
until #4254.
If src1 is known to be a number, either because it's not float or it's
an immediate number, use CMP. This allows cmod propagation to still do
its thing. Without this slight optimization, about 8,300 shaders from
shader-db are hurt on Iron Lake.
Fixes the following piglit tests (from piglit!475):
tests/spec/glsl-1.20/execution/fs-nan-builtin-max.shader_test
tests/spec/glsl-1.20/execution/fs-nan-builtin-min.shader_test
tests/spec/glsl-1.20/execution/vs-nan-builtin-max.shader_test
tests/spec/glsl-1.20/execution/vs-nan-builtin-min.shader_test
Closes: #4254
Fixes: 2f2c00c727 ("i965: Lower min/max after optimization on Gen4/5.")
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
Iron Lake and GM45 had similar results. (Iron Lake shown)
total instructions in shared programs: 8115134 -> 8115135 (<.01%)
instructions in affected programs: 229 -> 230 (0.44%)
helped: 0
HURT: 1
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/9027>
On Gen7, we have to split shuffles into two MOVs for 64-bit types so we
can't handle source modifiers. On Gen12.5, we have to use integer types
all the time so we can't use them there either. Fixing that will be a
different commit but it interacts with this one.
Fixes: 90c9f29518 "i965/fs: Add support for nir_intrinsic_shuffle"
Reviewed-by: Caio Marcelo de Oliveira Filho <caio.oliveira@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/9068>
I meant to do this years ago when I first added SHADER_OPCODE_SEND. At
the time, the only use for the extended descriptor was bindless handles
which were always one thing and never non-constant. However, it doesn't
actually require any extra instructions because we have to OR in ex_mlen
anyway.
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/8748>
We were using nir_tex_instr::dest_type to a glsl_type, then passing it
to emit_texture(), only to just check the number of components. Just
pass the number of components directly. This lets us delete
brw_glsl_base_type_for_nir_type, which was asserting with
nir_texop_all_samples_equal because it didn't handle bool32.
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/7989>
There are two problems this commit solves: First, is that the 64x64 MUL
lowering generates a Q MOV which, because of how late it runs in the
compile pipeline, it never gets removed. Second, it generates 32x32
MULs and we have to run it a second time to lower those.
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/7329>
We could probably support some strides if we tried hard enough but the
whole point of this opcode is to accelerate things with crazy Align16 or
crazy regions. It's ok if we have to emit an extra MOV to get a packed
source.
Fixes: 8b4a5e641b "intel/fs: Add support for subgroup quad operations"
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/7329>
Previously, we were returning 2 whenever the source was a Q type. As
far as I can tell, the only reason why this hasn't blown up before is
that it was only ever used for VGRFs until the SWSB pass landed which
uses it for everything. This wasn't a problem because Q types generally
aren't a thing on TGL. However, they are for a small handful of
instructions.
Cc: mesa-stable@lists.freedesktop.org
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/7329>
