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>
This is trying to clear a bit in the control register. However, it's
executing with whatever channel mask happens to be active. Typically
this is the one at the start of the program, so at least some channels
will be active. Typically the first channel will be active due to
packed dispatch, but that's not always guaranteed. Without NoMask,
the float controls writes may randomly not happen.
Recent GPUs also seem to have a hang issue when the first instruction in
the shader doesn't have any active channels. Having an instruction with
NoMask at the start of the program works around the issue. See HSD bug
14017989577. In our case, the float controls preamble was breaking that
restriction every time, causing us to run into this problem frequently.
Thanks to Tapani Pälli for finding this hang issue, and Francisco
Jerez and Lionel Landwerlin for helping pinpoint this issue during
review of a workaround patch in !20194.
Fixes GPU hangs in Elder Scrolls Online, Witcher 3, and likely more.
Closes: https://gitlab.freedesktop.org/mesa/mesa/-/issues/7639
Fixes: 9da56ffc52 ("i965/fs: add emit_shader_float_controls_execution_mode() and aux functions")
Reviewed-by: Francisco Jerez <currojerez@riseup.net>
Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Reviewed-by: Tapani Pälli <tapani.palli@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/20214>
The changes to fs_visitor::validate() helped track down a place where I
initially forgot to convert a message to the new sources layout. This
had caused a different validation failure in
dEQP-GLES31.functional.tessellation.tesscoord.triangles_equal_spacing,
but this were not detected until after SENDs were lowered.
Tiger Lake, Ice Lake, and Skylake had similar results. (Ice Lake shown)
total instructions in shared programs: 19951145 -> 19951133 (<.01%)
instructions in affected programs: 2429 -> 2417 (-0.49%)
helped: 8 / HURT: 0
total cycles in shared programs: 858904152 -> 858862331 (<.01%)
cycles in affected programs: 5702652 -> 5660831 (-0.73%)
helped: 2138 / HURT: 1255
Broadwell
total cycles in shared programs: 904869459 -> 904835501 (<.01%)
cycles in affected programs: 7686744 -> 7652786 (-0.44%)
helped: 2861 / HURT: 2050
Tiger Lake, Ice Lake, and Skylake had similar results. (Ice Lake shown)
Instructions in all programs: 141442369 -> 141442032 (-0.0%)
Instructions helped: 337
Cycles in all programs: 9099270231 -> 9099036492 (-0.0%)
Cycles helped: 40661
Cycles hurt: 28606
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/17605>
The lowering is currently fake. It just changes the opcode from the
_LOGICAL version to the non-_LOGICAL version.
v2: Remove some rebase cruft. 's/gfx8_//;s/simd8_/' in
brw_instruction_name. Both suggested by Ken.
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/17379>
Originally, we had virtual opcodes for scratch access, and let the
generator count spills/fills separately from other sends. Later, we
started using the generic SHADER_OPCODE_SEND for spills/fills on some
generations of hardware, and simply detected stateless messages there.
But then we started using stateless messages for other things:
- anv uses stateless messages for the buffer device address feature.
- nir_opt_large_constants generates stateless messages.
- XeHP curbe setup can generate stateless messages.
So counting stateless messages is not accurate. Instead, we move the
spill/fill accounting to the register allocator, as it generates such
things, as well as the load/store_scratch intrinsic handling, as those
are basically spill/fills, just at a higher level.
Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/16691>
In Fragment Shader, regular inputs are laid out in the thread payload
in a one dword per each half-GRF, that gives room for having the two
delta dwords needed for interpolation.
Per-primitive inputs are laid out before the regular inputs, and since
there's no need to have delta information, they are packed. So
half-GRF will be fully filled with 4 dwords of input.
When num_per_primitive_inputs is zero (the default case), behavior
should be the same as before.
Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/13661>
Instead of checking for MESA_SHADER_COMPUTE (and KERNEL). Where
appropriate, also use gl_shader_stage_is_compute().
This allows most of the workgroup-related lowering to be applied to
Task and Mesh shaders. These will be added later and "inherit" from
cs_prog_data structure.
Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/13629>
The source_depth_to_render_target flag can get set on old gen4-5 HW in a
few cases which are independent of the app writing gl_FragDepth. It
should be safe to just use fetch_payload_reg in that case instead of
depending in interpolation setup. This fixes a bug with certain very
simple shaders where we might end up not including the depth when we
should have.
While we're here, rework the logic around setting src_depth and add a
comment so it's more clear what's going on.
Fixes: 6d4070f3dd "intel/compiler: add support for fragment coordinate..."
Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/10596>
The PIXEL_X/Y opcodes used by the current implementation are broken on
XeHP due to the new regioning restrictions of the floating-point pipe.
We could have the regioning lowering pass fix it in theory by lowering
the conversions into separate MOV instructions, but that would be more
costly than this implementation that only needs a pair of pipelined
ADDs and a pair of pipelined MOVs.
Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/10000>
v2: Instead of fixing unitialized member 'fs_visitor::input_vue_map'
(as reported by Coverity Scan in defect CID 1474559),
remove unused members 'vec4_tcs_visitor::input_vue_map' and
'fs_visitor::input_vue_map'.
Also fixed 'debug_enabled' argument skipped in a fs_visitor constructor
call from brw_compile_tes().
Signed-off-by: Yevhenii Kharchenko <yevhenii.kharchenko@globallogic.com>
Reviewed-by: Caio Marcelo de Oliveira Filho <caio.oliveira@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/10040>
The Intel bindless thread dispatch model is very simple. When a compute
shader is to be used for bindless dispatch, it can request a set of
stack IDs. These are allocated per-dual-subslice by the hardware and
recycled automatically when the stack ID is returned. Passed to the
bindless dispatch are a global argument address, a stack ID, and an
address of the BINDLESS_SHADER_RECORD to invoke. When the bindless
shader is dispatched, it is passed its stack ID as well as the global
and local argument pointers. The local argument pointer is the address
of the BINDLESS_SHADER_RECORD plus some offset which is specified as
part of the BINDLESS_SHADER_RECORD.
Reviewed-by: Caio Marcelo de Oliveira Filho <caio.oliveira@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/7356>
These variables seem to be initialized before being used, so this
patch is not fixing any bug, but leaving them unitialized may become
a bug after some refactoring.
These classes were affected: fs_reg_alloc, fs_visitor, fs_generator,
instruction_scheduler.
Found by Coverity.
Signed-off-by: Marcin Ślusarz <marcin.slusarz@intel.com>
Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/6667>
We generate bitfields of bits that we want to retain (mask) and bits
that we want to set (brw_mode) in the cr0 register, so the bits we want
to set should be in the set of bits we want to retain.
Also, remove the initialization of mask from
fs_visitor::emit_shader_float_controls_execution_mode since
brw_rnd_mode_from_nir initializes the mask parameter unconditionally.
Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/5566>
This introduces an analysis pass intended to estimate several
performance statistics of the shader, including cycle count latency
and throughput values, based on static modeling. It has instruction
performance information more comprehensive than the current scheduling
pass for all platforms between Gen4-11, and works on both the FS and
VEC4 back-end.
The most immediate purpose of this pass is to implement a heuristic
meant to determine whether using SIMD32 dispatch for a fragment shader
can be expected to help more than it hurts. In addition this will
allow the effect of passes run after scheduling (e.g. the TGL software
scoreboard pass and the VEC4 dependency control pass) to be visible in
shader-db statistics.
But that isn't the end of the story, other potential applications of
this pass (not part of this MR) I've been playing around with are:
- Implement a similar SIMD16 heuristic allowing the identification of
inefficient SIMD16 fragment shaders.
- Implement similar SIMD16 and SIMD32 heuristics for the compute
shader stage -- Currently compute shader builds always use the
SIMD16 shader if available and never use the SIMD32 shader unless
strictly necessary, which is suboptimal under certain conditions.
- Hook up to the instruction scheduler in order to improve the
accuracy of its timing information.
- Use as heuristic in order to drive the selection of scheduling
modes (Matt was experimenting with that).
- Plug to the TGL software scoreboard pass in order to implement a
more effective SBID token allocation algorithm, since in general
the optimal token allocation depends on the timings of all
instructions in the program.
- Use its bottleneck detection functionality in order to implement a
heuristic computing a more optimal bound for the number of fragment
shader threads executed in parallel (by adjusting the
MaximumNumberofThreadsPerPSD control of 3DSTATE_PS).
As a follow-up I'm planning to submit updated timing information for
Gen12 platforms -- Everything else required to support Gen12 like SWSB
handling is already included in this patch, but there were some IP
concerns regarding the TGL timing parameters since they cannot
currently be obtained with the documentation and hardware which is
publicly available. The timing parameters for any previous Gen7-11
platforms can be obtained by anyone by sampling the timestamp register
using e.g. shader_time, though I have some more convenient
instrumentation coming up.
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Makes more sense considering SIMD32. Relaxing the assertion in
brw_ir_fs.h will be required in order to avoid assertion failures on
SNB with SIMD32 fragment shaders.
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
This applies the same work-around I commited as b84fa0b31e
"intel/fs/gen11: Work around dual-source blending hangs in combination
with SIMD32." to Gen12, which seems to suffer from the same hardware
bug found empirically. The failure mode seems to be identical.
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Change brw_compute_vue_map() to also take the number of pos slots. If
more than one slot is used, the VARYING_SLOT_POS is treated as an
array.
When using Primitive Replication, instead of a single position, the
VUE must contain an array of positions. Padding might be
necessary (after clip distance) to ensure rest of attributes start
aligned.
v2: Add note about array in the commit message and assert that
pos_slots >= 1 to make clear 0 is invalid. (Jason)
Move padding to be after the clip distance.
v3: Apply the correct offset when gathering the sources from outputs.
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net> [v2]
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Rafael Antognolli <rafael.antognolli@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/2313>