This implements support for OpenGL logic operations by emitting code to read
from the TLB if needed and blending the fragment output accordingly. It is
similar to VC4's blend lowering pass, but exclusive to logic operations, since
blending is otherwise supported in hardware.
The pass doesn't handle MSAA targets yet.
Fixes the following piglit tests:
spec/!opengl 1.0/gl-1.0-logicop/*
spec/!opengl 1.1/gl-1.1-xor
spec/!opengl 1.1/gl-1.1-xor-copypixels
It also fixes text cursor rendering in Libreoffice with the GTK+2 theme, which
is rendered via glamor using the XOR logic operation.
v2: fix checks for allowed variable location and maximum render target (Eric)
Reviewed-by: Eric Anholt <eric@anholt.net>
Until now we have always been emitting our scoreboard locks on the last thread
switch to improve parallelism. We did this by emitting our last thread switch
right before our tlb writes at the very end of the program, where we know that
we are outside control flow.
Unfortunately, this strategy is not valid when we have tlb color reads too, as
these will happen before this point in the program and can happen inside
control flow.
To fix this we always emit a thread switch before the first tlb load and if we
see additional thread switches after that point, we change the strategy to lock
on the first thread switch.
v2: change the solution so it is expected to work in more scenarios (Eric).
Reviewed-by: Eric Anholt <eric@anholt.net>
We need to scale the size of these arrays to consider up to
V3D_MAX_DRAW_BUFFERS render targets and 4 components per color.
v2: we want to store each color component separately, so scale by 4 too.
Reviewed-by: Eric Anholt <eric@anholt.net>
The ldtlbu version will read an implicit uniform with the TLB read
specifier and should be used for the first read in a sequence
of TLB reads (unless the default configuration is valid, in which
case we can use ldtlb). The ldtlb version is used for any subsequent
TLB read in the sequence.
Reviewed-by: Eric Anholt <eric@anholt.net>
We can use the same register spilling infrastructure for our loads/stores
of indirect access of temp variables, instead of doing an if ladder.
Cuts 50% of instructions and max-temps from 2 KSP shaders in shader-db.
Also causes several other KSP shaders with large bodies and large loop
counts to not be force-unrolled.
The change was originally motivated by NOLTIS slightly modifying register
pressure in piglit temp mat4 array read/write tests, triggering register
allocation failures.
While waiting for the CSD UABI to get reviewed, I keep having to rebase
the CS patch. Just land the compiler side for now to keep it from
diverging.
For now this covers just GLES 3.1 compute shaders, not CL kernels.
Our exec masking introduces lots of redundant flags updates, and even
without that there will be cases where NIR comparisons on the same sources
for different reasons may generate the same comparison instruction before
the selection.
total instructions in shared programs: 6492930 -> 6460934 (-0.49%)
total uniforms in shared programs: 2117460 -> 2115106 (-0.11%)
total spills in shared programs: 4983 -> 4987 (0.08%)
total fills in shared programs: 6408 -> 6416 (0.12%)
The idea was that we could skip uploading the constant-indexed uniform
data and just upload the uniforms that are variably-indexed. However,
since the VS bin and render shaders may have a different set of uniforms
used, this meant that we had to upload the UBO for each of them. The
first case is generally a fairly small impact (usually the uniform array
is the most space, other than a couple of FSes in shader-db), while the
second is a larger impact: 3DMMES2 was uploading 38k/frame of uniforms
instead of 18k.
Given that the optimization is of dubious value, has a big downside, and
is quite a bit of code, just drop it. No change in shader-db. No change
on 3DMMES2 (n=15).
We'd end up with the constant offset in the uniform stream anyway, since
they're bigger than small immediates. Avoids the extra uniforms and adds
in the shader in favor of just adding once on the CPU.
shader-db:
total instructions in shared programs: 6496865 -> 6494851 (-0.03%)
total uniforms in shared programs: 2119511 -> 2117243 (-0.11%)
I want to reuse this for encoding small constant UBO/SSBO offsets into the
uniform stream to reduce the extra uniform loads and adds for the small
constant offsets.
The idea is that for repeated use of the same uniform, we could avoid
loading it on each consumer. The results look pretty good.
total instructions in shared programs: 6413571 -> 6521464 (1.68%)
total threads in shared programs: 154214 -> 154000 (-0.14%)
total uniforms in shared programs: 2393604 -> 2119629 (-11.45%)
total spills in shared programs: 4960 -> 4984 (0.48%)
total fills in shared programs: 6350 -> 6418 (1.07%)
Once we do scheduling at the NIR level, the register pressure (and thus
also instructions) issues we see here will drop back down.
This lets us emit the VPM_WRITEs directly from
nir_intrinsic_store_output() (useful once NIR scheduling is in place so
that we can reduce register pressure), and lets future NIR scheduling
schedule the math to generate them. Even in the meantime, it looks like
this lets NIR DCE some more code and make better decisions.
total instructions in shared programs: 6429246 -> 6412976 (-0.25%)
total threads in shared programs: 153924 -> 153934 (<.01%)
total loops in shared programs: 486 -> 483 (-0.62%)
total uniforms in shared programs: 2385436 -> 2388195 (0.12%)
Acked-by: Ian Romanick <ian.d.romanick@intel.com> (nir)
In our backend, the successor edges from the blocks only point to where
QPU control flow goes, not where the notional control flow goes from a
"break" or "continue" modifying the execution mask to resume writing to
some channels later. As a result, this attempt at restricting live ranges
ended up missing the live range of a value where a conditional
break/continue was present in a loop before the later def of a variable.
The previous commit ended up fixing the problem that the flag tried to
solve.
Fixes glsl-vs-loop-continue.shader_test and/or
glsl-vs-loop-redundant-condition.shader_test based on register allocation
results.
In the backend, we often have condition codes on writes to variables, such
that there's no screening def anywhere and the previous live ranges
algorithm would conclude that the start of the range extends to the start
of the program. However, we do know that the live range can only extend
as early as you can reach from all blocks writing to the variable.
The motivation was that, while we have a couple of hacks to try to promote
conditional writes up to being a def within the block, the exec_mask one
was broken and needed a replacement.
Based on c3c1aa5aeb ("intel/fs: Restrict live intervals to the subset
possibly reachable from any definition.").
If we have a MOV of a uniform value available to spill, that's one of our
best choices. We can just not spill the value, and emit a new load of the
uniform as the fill. This saves bothering the TMU and the thrsw, and is
the same cost in uniforms (since the spill offset is a uniform anyway).
This doesn't have a huge impact on shader-db, since there aren't a whole
lot of spills and we usually copy-prop the uniforms at the VIR level such
that the only uniform MOVs are from vir_lower_uniforms:
total instructions in shared programs: 6430292 -> 6430279 (<.01%)
total uniforms in shared programs: 2386023 -> 2385787 (<.01%)
total spills in shared programs: 4961 -> 4960 (-0.02%)
total fills in shared programs: 6352 -> 6350 (-0.03%)
However, I'm interested in dropping the uniforms copy-prop in the backend,
since it would be cheaper to not load repeated uniforms if we have the
registers to spare. This also saves many spills on
dEQP-GLES31.functional.ubo.random.all_per_block_buffers.20, which is what
motivated a bunch of my recent backend work in the first place:
before: 46 spills, 106 fills, 3062 instructions
after: 0 spills, 0 fills, 2611 instructions
The execute.file check used to be good enough, until I stopped setting up
the execute mask for uniform ifs.
No known tests fixed, noticed while doing a refactor.
Fixes: 0805060573 ("v3d: Handle dynamically uniform IF statements with uniform control flow.")
You were allowed to pass in any old temp so that you could hopefully fold
the PF up into the def of the temp. If we couldn't find one, it
implicitly generated a MOV(nop, reg). However, that PF could have
different behavior depending on whether the def being folded into was a
float or int opcode, which the caller doesn't necessarily control.
Due to the fragility of the function, just switch all callers over to
vir_set_pf(). This also encourages the callers to use a _dest call for
the inst they're putting the PF on, eliminating a bunch of temps in the
pre-optimization VIR.
shader-db says the change is in the noise:
total instructions in shared programs: 6226247 -> 6227184 (0.02%)
instructions in affected programs: 851068 -> 852005 (0.11%)
Apparently we need disable-EZ flagged, not just "does Z writes".
Fixes
dEQP-GLES31.functional.image_load_store.early_fragment_tests.no_early_fragment_tests_depth_fbo
on 7278, even though it passed in simulation.
Signed-off-by: Eric Anholt <eric@anholt.net>
Fixes: 051a41d3d5 ("v3d: Add support for the early_fragment_tests flag.")
I had a single function for "does this do float input unpacking" with two
major flaws: It was missing the most common thing to try to copy propagate
a f32 input nunpack to (the VFPACK to an FP16 render target) along with
several other ALU ops, and also would try to propagate an f32 unpack into
a VFMUL which only does f16 unpacks.
instructions in affected programs: 659232 -> 655895 (-0.51%)
uniforms in affected programs: 132613 -> 135336 (2.05%)
and a couple of programs increase their thread counts.
The uniforms hit appears to be a pattern in generated code of doing (-a >=
a) comparisons, which when a is abs(b) can result in the abs instruction
being copy propagated once but not fully DCEed.
If you only bound rt 1+, we'd still emit a write to the rt0 that isn't
present (noticed while debugging an
ext_framebuffer_multisample-alpha-to-coverage-no-draw-buffer-zero
regression in another change).
We get a payload for the ivec3 workgroup and an int local invocation
index, and we use the core lowering to turn into the global invocation id
and the local invocation id ivec3s.
This is only exposed on V3D 4.1+, because we didn't have the TMU write
operations for images on 3.3 (To do GLES 3.1 there, you have to lower it
to SSBO load/stores, which is a problem to solve later).
Before, I had per-stage entryoints with some helpers shared between them.
As I extended for compute shaders and shader-db, it turned out that the
other common code in the middle wanted to be shared too.
This allows the original shader-db project's run.c runner to parse things
easily, and is probably a good thing to have for GL_ARB_debug_output in
general. I formatted it more like Intel's so I can mostly reuse their
report script.
The HW apparently has some issues (or at least a much more complicated VCM
calculation) with non-combined segments, and the closed source driver also
uses combined I/O. Until I get the last CTS failure resolved (which does
look plausibly like some VPM stomping), let's use combined I/O too.
