In a tesselation control shader where an input array is accessed using
the index gl_InvocationID, we can end up accessing elements beyond the
number of input vertices specified in the shader key.
This happens because of the lowering in nir_lower_indirect_derefs().
This lowering will affect compact variables which happens in this
case :
in gl_PerVertex {
vec4 gl_Position;
float gl_ClipDistance[1];
} gl_in[gl_MaxPatchVertices];
The lowered code produced by NIR is somewhat ineffecient (implements a
binary seach) :
if (gl_InvocationID < 16) {
if (gl_InvocationID < 8) {
if (gl_InvocationID < 4) {
vec4 vals = load_at_offset(0);
value = bcsel(vals, gl_InvocationID);
} else {
vec4 vals = load_at_offset(4);
value = bcsel(vals, gl_InvocationID - 4);
}
} else {
if (gl_InvocationID < 12) {
vec4 vals = load_at_offset(8);
value = bcsel(vals, gl_InvocationID - 8);
} else {
vec4 vals = load_at_offset(12);
value = bcsel(vals, gl_InvocationID - 12);
}
}
} else {
if (gl_InvocationID < 24) {
...
} else {
...
}
}
By default the gl_MaxPatchVertices must be set at 32 items and that's
what the lowering code will use to divide the access into chunks of 4.
But when running with 3 input vertices, this means we'll pull one more
item than what was delivered in the shader payload.
This triggers issues further down the register scheduling where the
g5UD (register for the 4th item) is overwritten by a previous SEND,
leading the URB read to use an invalid handle.
This pass clamps any access load_per_vertex_input intrinsic vertex
indice to (input_vertices - 1).
Fixes issues with tests like :
dEQP-VK.clipping.user_defined.clip_distance.vert_tess.*
Also fixes a hang with zink/anv on :
KHR-GL46.draw_elements_base_vertex_tests.AEP_shader_stages
v2: Don't replace source register
v3: Implement in NIR
v4: Clamp per vertex array sizes in NIR (Jason)
v5: Move the clamping on the intel compiler
Signed-off-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/9749>
Gfx8 and Gfx9 platforms are helped for cycles because now many
instructions like
mul(8) g12<1>D g10<8,8,1>D 6D
become
mul(8) g12<1>D g10<8,8,1>D 6W
It is the same number of instructions, but the 32x16 multiply is a
little faster.
v2: Fix transposed hi and lo in "(hi >= INT16_MIN && lo <= INT16_MAX)".
Noticed by Caio. Use nir_src_is_const instead of open coding it.
Suggested by Caio.
Broadwell and Skylake had similar results. (Skylake shown)
total cycles in shared programs: 845748380 -> 845145547 (-0.07%)
cycles in affected programs: 446346348 -> 445743515 (-0.14%)
helped: 6017
HURT: 0
helped stats (abs) min: 2 max: 7380 x̄: 100.19 x̃: 8
helped stats (rel) min: <.01% max: 3.72% x̄: 0.41% x̃: 0.39%
95% mean confidence interval for cycles value: -113.37 -87.00
95% mean confidence interval for cycles %-change: -0.42% -0.41%
Cycles are helped.
Skylake
Cycles in all programs: 8844820715 -> 8828897462 (-0.2%)
Cycles helped: 47914
Cycles hurt: 1
No shader-db or fossil-db changes on any other Intel platform.
Reviewed-by: Caio Oliveira <caio.oliveira@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/17718>
source_root function is deprecated in Meson version 0.56.0, so let's use
instead a current_source_dir() function, available in all Meson
versions. This also allows to deduplicate some code by declaring
commonly used string at the top meson.build file.
Signed-off-by: Konstantin Kharlamov <Hi-Angel@yandex.ru>
Reviewed-by: Emil Velikov <emil.l.velikov@gmail.com>.
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/17974>
This patch creates a new header file, brw_isa_info.h, which will
contains all the functions related to opcode encoding on various
generations. Opcode numbers may have different meanings on different
hardware, so we remap them between an enum we can easily work with
and the hardware encoding.
We move the brw_inst setters and getters to brw_inst.h.
Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/17309>
Commit 38800b38 changed nir_opcodes.py, but that doesn't seem to have
triggered nir_opt_algebraic.py. The change in 75ef5991 depends on
opt_algebraic lowering 16-bit versions of slt, but if opt_algebraic is
not rebuilt, this may not happen. This resulted in some people seeing
assertion failures in, for example,
dEQP-VK.spirv_assembly.instruction.compute.float16.arithmetic_3.step,
due to the backend seeing nir_op_slt that it didn't know how to handle.
v2: Add nir_opcodes.py to nir_algebraic_py so that all the per-driver
algebraic passes pick up the dependency too. Rename it to
nir_algebraic_depends. Suggested by Emma.
Closes: #6047
Fixes: d1992255bb ("meson: Add build Intel "anv" vulkan driver")
Reviewed-by: Emma Anholt <emma@anholt.net>
Acked-by: Dave Airlie <airlied@redhat.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/15050>
Task/Mesh stages are CS-like stages, and include many
builtins (e.g. workgroup ID/index) and intrinsics (e.g. workgroup
memory primitives) originally present only in CS.
This commit add two new stages (task and mesh) that 'inherit' from CS
by embedding a brw_cs_prog_data in their own prog_data structure, so
that CS functionality can be easily reused. They also currently use
the same helpers to select the SIMD variant to use -- that was
recently added for CS.
Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/13661>
Clean up the logic and move it to functions that work with prog_data
attributes to select the right SIMD. This shouldn't change any
behavior compared to the original.
Having it extracted will allow reuse by Task/Mesh and make it easier
to write tests.
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/13249>
With the `gtest` protocol meson will add some extra arguments to the
test to generate better junit results, which may be useful. This
protocol is only available in meson 0.55.0+, so keep using the default
`exitcode` protocol for meson older than that.
Reviewed-by: Caio Marcelo de Oliveira Filho <caio.oliveira@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/8484>
Each callable ray-tracing shader shader stage has to perform a return
operation at the end. In the case of raygen shaders, it retires the
bindless thread because the raygen shader is always the root of the call
tree. In the case of any-hit shaders, the default action is accep the
hit. For callable, miss, and closest-hit shaders, it does a return
operation. The assumption is that the calling shader has placed a
BINDLESS_SHADER_RECORD address for the return in the first QWord of the
callee's scratch space. The return operation simply loads this value
and calls a btd_spawn intrinsic to jump to it.
Reviewed-by: Caio Marcelo de Oliveira Filho <caio.oliveira@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/7356>
These will eventually contain per-stage lowering for various ray-tracing
things. This is separate from brw_nir_lower_rt_intrinsics because, for
reasons that will become apparent later, brw_nir_lower_rt_intrinsics has
to be run very late in the compile process, right before brw_compile_bs.
Reviewed-by: Caio Marcelo de Oliveira Filho <caio.oliveira@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/7356>
The new intrinsics we added for doing address calculations are all
things we fetch from the RT_DISPATCH_GLOBALS struct. We could emit an
RT_DISPATCH_GLOBALS load at every point we want it and trust NIR to CSE
it for us but it's easier to use intermediate intrinsics.
Reviewed-by: Caio Marcelo de Oliveira Filho <caio.oliveira@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/7356>
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>
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>
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>
Gen12 does not support RENDER_SURFACE_STATE::SurfaceArray = true &&
RENDER_SURFACE_STATE::Depth = 0. SurfaceArray can only be set to true
if Depth >= 1.
We workaround this limitation by adding the max(value, 1) snippet in
the shaders on the 3 components for texture array sizes.
Tested on Gen9 with the following Vulkan CTS tests :
dEQP-VK.image.image_size.2d_array.*
v2: Drop debug print (Tapani)
Switch to GEN:BUG instead of Wa_
v3: Fix dEQP-VK.image.image_size.1d_array.* cases (Lionel)
v4: Fix dEQP-VK.glsl.texture_functions.query.texturesize.* cases
(Missing tex_op handling) (Lionel)
v5: Missing break statement (Lionel)
v6: Fixup comment (Tapani)
v7: Fixup comment again (Tapani)
v8: Don't use sample_dim as index (Jason)
Rename pass
Simplify control flow
Signed-off-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Reviewed-by: Tapani Pälli <tapani.palli@intel.com> (v7)
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
Tested-by: Marge Bot <https://gitlab.freedesktop.org/mesa/mesa/merge_requests/3362>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/merge_requests/3362>
Importing this pass from fs_visitor::emit_alpha_to_coverage_workaround()
in intel/compiler.
v2 (Caio Marcelo de Oliveira Filho):
- Track store output and sample mask instruction
- Nest math insturction for more readability
- Bail out early if no gl_SampleMask
v3: (Caio Marcelo de Oliveira Filho):
- Do math instructions after instruction block
- Restructure code
- Move pass under src/intel/compiler
v4: (Caio Marcelo de Oliveira Filho):
- Organize dither mask calculation
Signed-off-by: Sagar Ghuge <sagar.ghuge@intel.com>
Reviewed-by: Caio Marcelo de Oliveira Filho <caio.oliveira@intel.com>
Tests the combinations of cases of RAW, WAW and WAR hazards involving
both inorder and outoforder instructions. Also tests that
dependencies combine and propagate correctly through control
flow (loops and conditionals).
v2: Add an extra test illustrating that the non-logical CFG edge
between then-block and else-block is being taking into
account. (Curro)
Reviewed-by: Francisco Jerez <currojerez@riseup.net>
Gen12+ hardware lacks the register scoreboard logic that used to
guarantee data coherency between register reads and writes in previous
generations. This lowering pass runs after register allocation in
order to make up for it.
It works by performing global dataflow analysis in order to determine
the set of potential dependencies of every instruction in the shader,
and then inserts any required SWSB annotations and additional SYNC
instructions in order to guarantee data coherency.
v2: Drop unnecessary _safe list iteration (Caio).
v3: Temporarily workaround potential WaR hazard between FPU
instruction and subsequent out-of-order write, pending
clarification from the hardware team. Drop redundant tracking of
implicit access of acc0-1, since the hardware guarantees coherency
of these (but not the other accumulators...).
Reviewed-by: Caio Marcelo de Oliveira Filho <caio.oliveira@intel.com>
This rewrites the current opcode description tables as a more compact
flat data structure. The purpose is to allow efficient constant-time
look-up by either HW or IR opcode, which will allow us to drop the
hard-coded correspondence between HW and IR opcodes -- See the next
commits for the rationale.
brw_eu.c is now built as C++ source so we can take advantage of
pointers to member in order to make the look-up function work
regardless of the opcode_desc member used as look-up key.
v2: Optimize devinfo struct comparison (Caio)
Reviewed-by: Caio Marcelo de Oliveira Filho <caio.oliveira@intel.com>
Reviewed-by: Jordan Justen <jordan.l.justen@intel.com>
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
This automates the include_directories and dependencies tracking so that
all users of libmesa_util don't need to add them manually.
Next commit will remove the ones that were only added for that reason.
Signed-off-by: Eric Engestrom <eric.engestrom@intel.com>
Acked-by: Eric Anholt <eric@anholt.net>
Tested-by: Vinson Lee <vlee@freedesktop.org>
Some conversions are not directly supported in hardware and need to be
split in two conversion instructions going through an intermediary type.
Doing this at the NIR level simplifies a bit the complexity in the backend.
v2:
- Consider fp16 rounding conversion opcodes
- Properly handle swizzles on conversion sources.
v3
- Run the pass earlier, right after nir_opt_algebraic_late (Jason)
- NIR alu output types already have the bit-size (Jason)
- Use 'is_conversion' to identify conversion operations (Jason)
v4:
- Be careful about the intermediate types we use so we don't lose
range and avoid incorrect rounding semantics (Jason)
Reviewed-by: Topi Pohjolainen <topi.pohjolainen@intel.com> (v1)
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
The i965 driver has a bunch of code to compare two sets of program keys
and print out the differences. This can be useful for debugging why a
shader needed to be recompiled on the fly due to non-orthogonal state
dependencies. anv doesn't do recompiles, so we didn't need to share
this in the past - but I'd like to use it in iris.
This moves the bulk of the code to the compiler where it can be reused.
To make that possible, we need to decouple it from i965 - we can't get
at the brw program cache directly, nor use brw_context to print things.
Instead, we use compiler->shader_perf_log(), and simply pass in keys.
We put all of this debugging code in brw_debug_recompile.c, and only
export a single function, for simplicity. I also tidied the code a
bit while moving it, now that it all lives in one file.
Reviewed-by: Jordan Justen <jordan.l.justen@intel.com>
All of the actual abstraction (except possibly setting size_written)
happens as part of the logical opcodes. The only thing that the surface
builder is providing at this point is extra levels of functions to call
through. I'm going to be adding bindless image support soon and all the
extra abstraction here is just getting in the way.
Reviewed-by: Caio Marcelo de Oliveira Filho <caio.oliveira@intel.com>
