This change incurs a small amount of hurt now, but it enables a lot of
benefit on vec4 shaders on the next commit. nir_opt_algebraic_late
converts dph, dot3, etc. to dhp_replicated, dot_replicated3, etc. In
the process, it introduces extra moves. If the original NIR contained
vec1 32 ssa_45 = fdot4 ssa_51, ssa_44
vec1 32 ssa_46 = fneg ssa_45
nir_opt_algebraic_late will produce
vec4 32 ssa_18 = fdot_replicated4 ssa_1, ssa_15
vec1 32 ssa_19 = mov ssa_18.x
vec1 32 ssa_17 = fneg ssa_19
The algebraic pass added in the next commit can't see through the move
to know that the fneg applies to a fdot_replicated4.
Haswell, Ivy Bridge, and Sandybridge had similar results. (Haswell shown)
total cycles in shared programs: 187077604 -> 187079858 (<.01%)
cycles in affected programs: 350132 -> 352386 (0.64%)
helped: 174
HURT: 194
helped stats (abs) min: 2 max: 124 x̄: 23.60 x̃: 16
helped stats (rel) min: 0.12% max: 15.88% x̄: 4.98% x̃: 3.86%
HURT stats (abs) min: 2 max: 164 x̄: 32.78 x̃: 16
HURT stats (rel) min: 0.17% max: 22.82% x̄: 6.46% x̃: 0.86%
95% mean confidence interval for cycles value: 2.04 10.21
95% mean confidence interval for cycles %-change: 0.17% 1.93%
Cycles are HURT.
No shader-db changes on any other Intel platform.
Reviewed-by: Matt Turner <mattst88@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/1359>
Let's make it clear what includes are being added everywhere, so that
they can be cleaned up.
Signed-off-by: Eric Engestrom <eric@engestrom.ch>
Reviewed-by: Marek Olšák <marek.olsak@amd.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/4360>
This has been reported to fix a hang in Shadow of Mordor on Gen12.
One of its compute shaders seems to cause an in-order exec_all
dependency to be merged into an out-of-order SET dependency slot,
which would prevent us from baking the SET dependency into the parent
instruction, leading to an assert failure in emit_inst_dependencies()
(Thanks to Rafael for noticing that). Prevent that by avoiding
combination of in-order dependencies whenever that would cause a SET
dependency to be demoted to a SYNC.NOP instruction.
Fixes: e14529ff32 "intel/fs/gen12: Workaround data coherency issues due to broken NoMask control flow."
Tested-by: Rafael Antognolli <rafael.antognolli@intel.com>
Reviewed-by: Caio Marcelo de Oliveira Filho <caio.oliveira@intel.com>
Return the number of patches to accumulate before an 8_PATCH mode thread
is launched.
v2: (Kenneth Graunke)
- Track patch count threshold instead of input control points.
Signed-off-by: Sagar Ghuge <sagar.ghuge@intel.com>
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/3563>
Patch adds a new arg and modifies existing calls from i965, anv
pass NULL but iris stores this information for later use.
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/4080>
This will avoid generating multiple identical fences in a row.
For Gen11+ we have multiple types of fences (affecting different
variable modes), but is still better to combine them in a single
scoped barrier so that the translation to backend IR have the option
of dispatching both fences in parallel.
This will clean up redundant barriers from various
dEQP-VK.memory_model.* tests.
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
Tested-by: Marge Bot <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/3224>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/3224>
Knowing following:
- CMP writes to flag register the result of
applying cmod to the `src0 - src1`.
After that it stores the same value to dst.
Other instructions first store their result to
dst, and then store cmod(dst) to the flag
register.
- inst is either CMP or MOV
- inst->dst is null
- inst->src[0] overlaps with scan_inst->dst
- inst->src[1] is zero
- scan_inst wrote to a flag register
There can be three possible paths:
- scan_inst is CMP:
Considering that src0 is either 0x0 (false),
or 0xffffffff (true), and src1 is 0x0:
- If inst's cmod is NZ, we can always remove
scan_inst: NZ is invariant for false and true. This
holds even if src0 is NaN: .nz is the only cmod,
that returns true for NaN.
- .g is invariant if src0 has a UD type
- .l is invariant if src0 has a D type
- scan_inst and inst have the same cmod:
If scan_inst is anything than CMP, it already
wrote the appropriate value to the flag register.
- else:
We can change cmod of scan_inst to that of inst,
and remove inst. It is valid as long as we make
sure that no instruction uses the flag register
between scan_inst and inst.
Nine new cmod_propagation unit tests:
- cmp_cmpnz
- cmp_cmpg
- plnnz_cmpnz
- plnnz_cmpz (*)
- plnnz_sel_cmpz
- cmp_cmpg_D
- cmp_cmpg_UD (*)
- cmp_cmpl_D (*)
- cmp_cmpl_UD
(*) this would fail without changes to brw_fs_cmod_propagation.
This fixes optimisation that used to be illegal (see issue #2154)
= Before =
0: linterp.z.f0.0(8) vgrf0:F, g2:F, attr0<0>:F
1: cmp.nz.f0.0(8) null:F, vgrf0:F, 0f
= After =
0: linterp.z.f0.0(8) vgrf0:F, g2:F, attr0<0>:F
Now it is optimised as such (note change of cmod in line 0):
= Before =
0: linterp.z.f0.0(8) vgrf0:F, g2:F, attr0<0>:F
1: cmp.nz.f0.0(8) null:F, vgrf0:F, 0f
= After =
0: linterp.nz.f0.0(8) vgrf0:F, g2:F, attr0<0>:F
No shaderdb changes
Closes: https://gitlab.freedesktop.org/mesa/mesa/issues/2154
Signed-off-by: Yevhenii Kolesnikov <yevhenii.kolesnikov@globallogic.com>
Reviewed-by: Matt Turner <mattst88@gmail.com>
Tested-by: Marge Bot <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/3348>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/3348>
Avoid looping over all VARYING_SLOT_MAX urb_setup array
entries from genX_upload_sbe. Prepare an array indirection
to the active entries of urb_setup already in the compile
step. On upload only walk the active arrays.
v2: Use uint8_t to store the attribute numbers.
v3: Change loop to build up the array indirection.
v4: Rebase.
v5: Style fix.
Reviewed-by: Matt Turner <mattst88@gmail.com>
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
Signed-off-by: Mathias Fröhlich <Mathias.Froehlich@web.de>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/308>
The current workaround for this hardware bug involved marking the ADD
instruction used to initialize the address register as NoMask on
Gen12, which was based on the assumption that the problem was caused
by a hardware bug affecting the application of the execution mask to
the address register write.
However that doesn't seem to be the case: The address register write
was working correctly, the real problem leading to hangs on TGL is
that the indirect addressing logic is unable to deal with garbage
values in the address register (e.g. misaligned offsets), even for
channels which are currently inactive due to non-uniform control flow.
The current workaround isn't able to avoid that situation in general,
since the result of the NoMask ADD instruction for a dead channel is
calculated based on the corresponding (dead) component of the
indirect_byte_offset source, which would still be undefined in the
likely case that the source was initialized under control flow itself.
This would lead to hangs whenever MOV_INDIRECT was used under
non-uniform control flow in some scenarios like a tessellation shader
from GFXBench5/gl_4 (AKA Car Chase) on TGL. In addition I've managed
to reproduce the same issue on earlier platforms by initializing the
whole address register with garbage before the ADD instruction, so
this seems to be a long-standing issue we have avoided mostly by luck.
This patch fixes the problem and applies the workaround to all
platforms, since even when the hardware is able to deal with garbage
address values without hanging there might be a significant
performance cost from reading random GRF registers due to the useless
extra EU cycles spent fetching registers for dead channels and due to
the potential for unintended serialization with respect to other
random instructions that could be executed in parallel, which may have
had a cost of the order of hundreds of cycles in the worst case
scenario.
Fixes: f93dfb509c "intel/fs: Write the address register with NoMask for MOV_INDIRECT"
Tested-by: Rafael Antognolli <rafael.antognolli@intel.com>
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
Passing shader_stats to the fs_generator constructor means that the
SIMD8 shader stats from the visitor (such as the scheduler mode) will be
reported out for the SIMD16/SIMD32 versions as well.
As you can see, we are now passing 'shader_stats' and 'stats' to
generate_code(), which is obviously odd looking. Ian rebased and
committed an old patch of mine which added the shader_stats struct on
July 30 in commit dabb5d4bee (i965/fs: Add a shader_stats struct.) and
shortly after on August 12 Jason added the brw_compile_stats struct in
commit 134607760a (intel/compiler: Fill a compiler statistics struct).
I'd like to combine the two, but I'm not sure how. shader_stats is an
input to generate_code() while brw_compile_stats is an output and is
only used by the Vulkan driver. Leave it as is for now...
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/4093>
This defines a new BRW_ANALYSIS object which wraps the register
pressure computation code along with its result. For the rationale
see the previous commits converting the liveness and dominance
analysis passes to the IR analysis framework.
Reviewed-by: Matt Turner <mattst88@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/4012>
It makes sense to keep the result of analysis passes independent from
the IR itself. Instead of representing the idom tree as a pointer in
each basic block pointing to its immediate dominator, the whole
dominator tree is represented separately from the IR as an array of
pointers inside the idom_tree object. This has the advantage that
it's no longer possible to use stale dominance results by accident
without having called require() beforehand, which makes sure that the
idom tree is recalculated if necessary.
Reviewed-by: Matt Turner <mattst88@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/4012>
This only does half of the work. The actual representation of the
idom tree is left untouched, but the computation algorithm is moved
into a separate analysis result class wrapped in a BRW_ANALYSIS
object, along with the intersect() and dump_domtree() auxiliary
functions in order to keep things tidy.
Reviewed-by: Matt Turner <mattst88@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/4012>
This involves wrapping vec4_live_variables in a BRW_ANALYSIS object
and hooking it up to invalidate_analysis() so it's properly
invalidated. Seems like a lot of churn but it's fairly
straightforward. The vec4_visitor invalidate_ and
calculate_live_intervals() methods are no longer necessary after this
change.
Reviewed-by: Matt Turner <mattst88@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/4012>
This involves wrapping fs_live_variables in a BRW_ANALYSIS object and
hooking it up to invalidate_analysis() so it's properly invalidated.
Seems like a lot of churn but it's fairly straightforward. The
fs_visitor invalidate_ and calculate_live_intervals() methods are no
longer necessary after this change.
Reviewed-by: Matt Turner <mattst88@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/4012>
This could be improved somewhat with additional validation of the
calculated live in/out sets and by checking that the calculated live
intervals are minimal (which isn't strictly necessary to guarantee the
correctness of the program). This should be good enough though to
catch accidental use of stale liveness results due to missing or
incorrect analysis invalidation.
Reviewed-by: Matt Turner <mattst88@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/4012>
This could be improved somewhat with additional validation of the
calculated live in/out sets and by checking that the calculated live
intervals are minimal (which isn't strictly necessary to guarantee the
correctness of the program). This should be good enough though to
catch accidental use of stale liveness results due to missing or
incorrect analysis invalidation.
Reviewed-by: Matt Turner <mattst88@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/4012>
This removes the dependency of fs_live_variables on fs_visitor. The
IR analysis framework requires the analysis result to be constructible
with a single argument -- The second argument was redundant anyway.
Reviewed-by: Matt Turner <mattst88@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/4012>
This makes the structure of the vec4 live intervals calculation more
similar to the FS back-end liveness analysis code. The non-CF-aware
start/end computation is moved into the same pass that calculates the
block-local def/use sets, which saves quite a bit of code, while the
CF-aware start/end computation is moved into a separate
compute_start_end() function as is done in the FS back-end.
Reviewed-by: Matt Turner <mattst88@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/4012>
This moves the following methods that are currently defined in
vec4_visitor (even though they are side products of the liveness
analysis computation) and are already implemented in
brw_vec4_live_variables.cpp:
> int var_range_start(unsigned v, unsigned n) const;
> int var_range_end(unsigned v, unsigned n) const;
> bool virtual_grf_interferes(int a, int b) const;
> int *virtual_grf_start;
> int *virtual_grf_end;
It makes sense for them to be part of the vec4_live_variables object,
because they have the same lifetime as other liveness analysis results
and because this will allow some extra validation to happen wherever
they are accessed in order to make sure that we only ever use
up-to-date liveness analysis results.
The naming of the virtual_grf_start/end arrays was rather misleading,
they were indexed by variable rather than by vgrf, this renames them
start/end to match the FS liveness analysis pass. The churn in the
definition of var_range_start/end is just in order to avoid a
collision between the start/end arrays and local variables declared
with the same name.
Reviewed-by: Matt Turner <mattst88@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/4012>
This moves the following methods that are currently defined in
fs_visitor (even though they are side products of the liveness
analysis computation) and are already implemented in
brw_fs_live_variables.cpp:
> bool virtual_grf_interferes(int a, int b) const;
> int *virtual_grf_start;
> int *virtual_grf_end;
It makes sense for them to be part of the fs_live_variables object,
because they have the same lifetime as other liveness analysis results
and because this will allow some extra validation to happen wherever
they are accessed in order to make sure that we only ever use
up-to-date liveness analysis results.
This shortens the virtual_grf prefix in order to compensate for the
slightly increased lexical overhead from the live_intervals pointer
dereference.
Reviewed-by: Matt Turner <mattst88@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/4012>
Have fun reading through the whole back-end optimizer to verify
whether I've missed any dependency flags -- Or alternatively, just
trust that any mistake here will trigger an assertion failure during
analysis pass validation if it ever poses a problem for the
consistency of any of the analysis passes managed by the framework.
Reviewed-by: Matt Turner <mattst88@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/4012>
I've deliberately separated this from the general analysis pass
infrastructure in order to discuss it independently. The dependency
classes defined here refer to state changes of several objects of the
program IR, and are fully orthogonal and expected to change less often
than the set of analysis passes present in the compiler back-end.
The objective is to avoid unnecessary coupling between optimization
and analysis passes in the back-end. By doing things in this way the
set of flags to be passed to invalidate_analysis() can be determined
from knowledge of a single optimization pass and a small set of well
specified dependency classes alone -- IOW there is no need to audit
all analysis passes to find out which ones might be affected by
certain kind of program transformation performed by an optimization
pass, as well as the converse, there is no need to audit all
optimization passes when writing a new analysis pass to find out which
ones can potentially invalidate the result of the analysis.
The set of dependency classes defined here is rather conservative and
mainly based on the requirements of the few analysis passes already
part of the back-end. I've also used them without difficulty with a
few additional analysis passes I've written but haven't yet sent for
review.
Reviewed-by: Matt Turner <mattst88@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/4012>
The invalidate_analysis() method knows what analysis passes there are
in the back-end and calls their invalidate() method to report changes
in the IR. For the moment it just calls invalidate_live_intervals()
(which will eventually be fully replaced by this function) if anything
changed.
This makes all optimization passes invalidate DEPENDENCY_EVERYTHING,
which is clearly far from ideal -- The dependency classes passed to
invalidate_analysis() will be refined in a future commit.
Reviewed-by: Matt Turner <mattst88@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/4012>
Motivated in detail in the source code. The only piece missing here
from the analysis pass infrastructure is some sort of mechanism to
broadcast changes in the IR to all existing analysis passes, which
will be addressed by a future commit. The analysis_dependency_class
enum might seem a bit silly at this point, more interesting dependency
categories will be defined later on.
Reviewed-by: Matt Turner <mattst88@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/4012>
brw_vec4.h (in particular vec4_visitor) is logically a user of the
live variables analysis pass, not the other way around.
brw_vec4_live_variables.h requires the definition of some VEC4 IR data
structures to compile, but those can be obtained directly from
brw_ir_vec4.h without including brw_vec4.h.
Reviewed-by: Matt Turner <mattst88@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/4012>
brw_fs.h (in particular fs_visitor) is logically a user of the live
variables analysis pass, not the other way around.
brw_fs_live_variables.h requires the definition of some FS IR data
structures to compile, but those can be obtained directly from
brw_ir_fs.h without including brw_fs.h. The dependency of
fs_live_variables on fs_visitor is rather accidental and will be
removed in a future commit, a forward declaration is enough for the
moment.
Reviewed-by: Matt Turner <mattst88@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/4012>
When this commit was originally written, these two structures had the
exact same name. Subsequently in commit 12a8f2616a (intel/compiler:
Fix C++ one definition rule violations) they were renamed.
Original commit message:
> These two structures have exactly the same name which prevents the two
> files from being included at the same time and could cause serious
> trouble in the future if it ever leads to a (silent) violation of the
> C++ one definition rule.
Reviewed-by: Matt Turner <mattst88@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/4012>
This reflects the natural dependency relationship between brw_cfg.h
and brw_shader.h. brw_cfg.h only requires the base IR definitions
which are now part of a separate header.
Reviewed-by: Matt Turner <mattst88@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/4012>
This pulls out the i965 IR definitions into a separate file and leaves
the top-level backend_shader structure and back-end compiler entry
points in brw_shader.h. The purpose is to keep things tidy and
prevent a nasty circular dependency between brw_cfg.h and
brw_shader.h. The logical dependency between these data structures
looks like:
backend_shader (brw_shader.h) -> cfg_t (brw_cfg.h)
-> bblock_t (brw_cfg.h) -> backend_instruction (brw_shader.h)
This circular header dependency is currently resolved by using forward
declarations of cfg_t/bblock_t in brw_shader.h and having brw_cfg.h
include brw_shader.h, which seems backwards and won't work at all when
the forward declarations of cfg_t/bblock_t are no longer sufficient in
a future commit.
Reviewed-by: Matt Turner <mattst88@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/4012>
Our current GPGPU_WALKER code only supports up to 64 threads.
On HSW we could use up to 70 and TGL up to 112, but only if the walker
is adjusted so the width does not exceed 64. Work to support this is
in progress.
Previous to this change, we might try to downgrade to SIMD8 if the
SIMD16 shader spilled. Since HSW and TGL have the max number of
threads above 64, we would then try to emit an invalid GPGPU walker
command.
Fixes: 932045061b ("i965/cs: Emit compute shader code and upload programs")
Signed-off-by: Jordan Justen <jordan.l.justen@intel.com>
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
Reviewed-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Tested-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
