On some architectures, Boolean values used to control conditional
branches or condtional selection must be propagated into a flag. This
generally means that a stored Boolean value must be compared with zero.
Rather than force the generation of extra compares with zero, re-emit
the original comparison instruction. This can save register pressure by
not needing to store the Boolean value.
There are several possible ares for future improvement to this pass:
1. Be more conservative. If both sources to the comparison instruction
are non-constants, it may be better for register pressure to emit the
extra compare. The current shader-db results on Intel GPUs (next
commit) lead me to believe that this is not currently a problem.
2. Be less conservative. Currently the pass requires that all users of
the comparison match the pattern. The idea is that after the pass is
complete, no instruction will use the resulting Boolean value. The only
uses will be of the flag value. It may be beneficial to relax this
requirement in some cases.
3. Be less conservative. Also try to rematerialize comparisons used for
discard_if intrinsics. After changing the way the Intel compiler
generates cod e for discard_if (see MR!935), I tried implementing this
already. The changes were pretty small. Instructions were helped in 19
shaders, but, overall, cycles were hurt. A commit "nir: Rematerialize
comparisons for nir_intrinsic_discard_if too" is on my fd.o cgit.
4. Copy the preceeding ALU instruction. If the comparison is a
comparison with zero, and it is the only user of a particular ALU
instruction (e.g., (a+b) != 0.0), it may be a further improvment to also
copy the preceeding ALU instruction. On Intel GPUs, this may enable
cmod propagation to make additional progress.
v2: Use much simpler method to get the prev_block for an if-statement.
Suggested by Tim.
Reviewed-by: Matt Turner <mattst88@gmail.com>
Lower sin and cos using Nick's fast sin/cos approximation from
https://web.archive.org/web/20180105155939/http://forum.devmaster.net/t/fast-and-accurate-sine-cosine/9648
It's suitable for GLES2, but it throws warnings in dEQP GLES3 precision tests.
Reviewed-by: Connor Abbott <cwabbott0@gmail.com>
Reviewed-by: Qiang Yu <yuq825@gmail.com>
Tested-by: Qiang Yu <yuq825@gmail.com>
Reviewed-by: Christian Gmeiner <christian.gmeiner@gmail.com>
Signed-off-by: Vasily Khoruzhick <anarsoul@gmail.com>
This pass will soon grow to include some optimizations that are
difficult or impossible to implement correctly within nir_opt_algebraic.
It also include the ability to generate strictly correct code which the
current nir_opt_algebraic lowering lacks (though that could be changed).
v2: Document the parameters to nir_lower_flrp. Rebase on top of
3766334923 ("compiler/nir: add lowering for 16-bit flrp")
Reviewed-by: Matt Turner <mattst88@gmail.com>
This new pass lowers ints and bools to floats. It allows hardware
that doesn't have native integers (e.g. Mali4x0) use the same
code paths as modern hardware.
It uses newly introduced pass to gather SSA types and should be
used as late as possible.
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
Reviewed-by: Christian Gmeiner <christian.gmeiner@gmail.com>
Signed-off-by: Vasily Khoruzhick <anarsoul@gmail.com>
In commit a99c360a46 (nir: add pass to lower fb reads), a new
file was added that needs to also be added to the
Makefile.sources list used by the Android and SCons build system.
Cc: Rob Clark <robdclark@chromium.org>
Cc: Emil Velikov <emil.l.velikov@gmail.com>
Cc: Amit Pundir <amit.pundir@linaro.org>
Cc: Sumit Semwal <sumit.semwal@linaro.org>
Cc: Alistair Strachan <astrachan@google.com>
Cc: Greg Hartman <ghartman@google.com>
Cc: Tapani Pälli <tapani.palli@intel.com>
Cc: Jason Ekstrand <jason@jlekstrand.net>
Fixes: a99c360a46 ("nir: add pass to lower fb reads")
Reviewed-by: Tapani Pälli <tapani.palli@intel.com>
Reviewed-by: Emil Velikov <emil.velikov@collabora.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
This new pass (which isn't even compile-tested) attempts to determine
the ALU type of all the SSA values in a function impl. It takes a
greedy approach and assigns intness or floatness to everything it thinks
can possibly contain an int or a float. Some values will be labled as
both int and float and some will be labled as neither and it is up to
the caller to decide what to do with this information. However, for a
"nice" shader where the original source contained no bit-casts and no
implicit bit-casts were introduced by optimizations, there shouldn't be
any overlap in the two sets save for the odd CSEd zero constant.
Reviewed-by: Vasily Khoruzhick <anarsoul@gmail.com>
On some hardware (e.g. Mali400) the shader needs to apply some
transformations for correct gl_FragCoord handling. The lowering
actions look like the following in pseudocode:
gl_FragCoord.xyz = gl_FragCoord_orig.xyz
gl_FragCoord.w = 1.0 / gl_FragCoord_orig.w
Add this lowering as a nir pass in preparation for using it in the driver.
Signed-off-by: Andreas Baierl <ichgeh@imkreisrum.de>
Reviewed-by: Qiang Yu <yuq825@gmail.com>
Reviewed-by: Eric Anholt <eric@anholt.net>
On Mali hardware (supported by Panfrost and Lima), the fixed-function
transformation from world-space to screen-space coordinates is done in
the vertex shader prior to writing out the gl_Position varying, rather
than in dedicated hardware. This commit adds a shared NIR pass for
implementing coordinate transformation and lowering gl_Position writes
into screen-space gl_Position writes.
v2: Run directly on derefs before io/vars are lowered to cleanup the
code substantially. Thank you to Qiang for this suggestion!
v3: Bikeshed continues.
v4: Add to Makefile.sources (per Jason's comment). Bikeshed comment.
Ian and Qiang's reviews are from v3, but no real functional changes from
v4. Rob's review is from v4.
Signed-off-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
Suggested-by: Qiang Yu <yuq825@gmail.com>
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
Reviewed-by: Qiang Yu <yuq825@gmail.com>
Reviewed-by: Rob Clark <robdclark@gmail.com>
This commit adds new nir_load/store_scratch opcodes which read and write
a virtual scratch space. It's up to the back-end to figure out what to
do with it and where to put the actual scratch data.
v2: Drop const_index comments (by anholt)
Reviewed-by: Eric Anholt <eric@anholt.net>
v2: handle atomics as well
make use of nir_rewrite_image_intrinsic
v3: remove call to nir_remove_dead_derefs
v4: (Timothy Arceri) dont actually call lowering yet
Signed-off-by: Karol Herbst <kherbst@redhat.com>
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net> (v3)
Reviewed-by: Marek Olšák <marek.olsak@amd.com>
We have a pass to lower global registers to locals and many drivers
dutifully call it. However, no one ever creates a global register ever
so it's all dead code. It's time we bury it.
Acked-by: Karol Herbst <kherbst@redhat.com>
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
This pass attempts to dectect code sequences like
if (x < y) {
z = y - x;
...
}
and replace them with sequences like
t = x - y;
if (t < 0) {
z = -t;
...
}
On architectures where the subtract can generate the flags used by the
if-statement, this saves an instruction. It's also possible that moving
an instruction out of the if-statement will allow
nir_opt_peephole_select to convert the whole thing to a bcsel.
Currently only floating point compares and adds are supported. Adding
support for integer will be a challenge due to integer overflow. There
are a couple possible solutions, but they may not apply to all
architectures.
v2: Fix a typo in the commit message and a couple typos in comments.
Fix possible NULL pointer deref from result of push_block(). Add
missing (-A + B) case. Suggested by Caio.
v3: Fix is_not_const_zero to work correctly with types other than
nir_type_float32. Suggested by Ken.
v4: Add some comments explaining how this works. Suggested by Ken.
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
This lowering isn't needed for RADV because AMDGCN has two
instructions. It will be disabled for RADV in an upcoming series.
While we are at it, factorize a little bit.
Signed-off-by: Samuel Pitoiset <samuel.pitoiset@gmail.com>
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
This pass was originally written for lowering TCS output reads and
writes but it is also applicable just about anything including UBOs,
SSBOs, and shared variables.
Reviewed-by: Caio Marcelo de Oliveira Filho <caio.oliveira@intel.com>
v2: (all from Jason)
Reuse existing function for the end of the block combinations.
Check the SSA values are coming from the right place in tests.
Document the case when the store to array_deref is reused.
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
Oftentimes various nir shaders after lowering will be the same, or
almost the same. For example, this can happen when the same shader is
linked with different shaders to form different pipelines and
cross-stage optimizations don't kick in to change it. We want to avoid
running the backend twice on these shaders. We were already doing this
with radeonsi, but we were storing a few extra pieces of information
that made this much less effective compared to TGSI. The worse offender
by far was the program name, which caused most of the cache misses. This
pass strips out these pieces of information, controlled by the NIR_STRIP
debug env variable.
Reviewed-by: Timothy Arceri <tarceri@itsqueeze.com>
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
Not complete, mostly just adding things as I encounter them in CTS. But
not getting far enough yet to hit most of the OpenCL.std instructions.
Anyway, this is better than nothing and covers the most common builtins.
v2: add hadd proof from Jason
move some of the lowering into opt_algebraic and create new nir opcodes
simplify nextafter lowering
fix normalize lowering for inf
rework upsample to use nir_pack_bits
add missing files to build systems
v3: split lines of iadd/sub_sat expressions
Signed-off-by: Karol Herbst <kherbst@redhat.com>
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
The nir_lower_uniforms_to_ubo function is useful outside of
mesa/state_tracker, and in fact is needed to produce NIR for
drivers that have the PIPE_CAP_PACKED_UNIFORMS capability.
Signed-Off-By: Timur Kristóf <timur.kristof@gmail.com>
Tested-by: Andre Heider <a.heider@gmail.com>
Tested-by: Rob Clark <robdclark@gmail.com>
Reviewed-by: Timothy Arceri <tarceri@itsqueeze.com>
Reviewed-by: Eric Anholt <eric@anholt.net>
From @jekstrand's nir-1-bit-bool branch, with improved ior/inot lowering.
ior: fmax instead of fadd allows removing the fsat.
inot: seq(x, 0) can be better than fsub(1, x). On a2xx, it works better
with the scalar instruction set.
Reviewed-by: Jonathan Marek <jonathan@marek.ca>
The following patches will add implementations of various
double-precision operations to this file.
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
We also enable it in all of the NIR drivers.
Reviewed-by: Eric Anholt <eric@anholt.net>
Reviewed-by: Bas Nieuwenhuizen <bas@basnieuwenhuizen.nl>
Tested-by: Bas Nieuwenhuizen <bas@basnieuwenhuizen.nl>
It's a reasonably well-known fact in the world of compilers that integer
divisions by constants can be replaced by a multiply, an add, and some
shifts. This commit adds such an optimization to NIR for easiest case
of udiv. Other division operations will be added in following commits.
In order to provide some additional driver control, the pass takes a
minimum bit size to optimize.
Reviewed-by: Ian Romanick ian.d.romanick@intel.com
This is different from the GL_ARB_spirv pass because it generates a much
simpler data structure that isn't tied to OpenGL and mtypes.h.
Reviewed-by: Samuel Pitoiset <samuel.pitoiset@gmail.com>
Instead of doing this as part of the existing copy_prop_vars pass.
Separation makes easier to expand the scope of both passes to be more
than per-block. For copy propagation, the information about valid
copies comes from previous instructions; while the dead write removal
depends on information from later instructions ("have any instruction
used this deref before overwrite it?").
Also change the tests to use this pass (instead of copy prop vars).
Note that the disabled tests continue to fail, since the standalone
pass is still per-block.
v2: Remove entries from dynarray instead of marking items as
deleted. Use foreach_reverse. (Caio)
(all from Jason)
Do not cache nir_deref_path. Not worthy for this patch.
Clear unused writes when hitting a call instruction.
Clean up enumeration of modes for barriers.
Move metadata calls to the inner function.
v3: For copies, use the vector length to calculate the mask.
(all from Jason)
Use nir_component_mask_t when applicable.
Rename functions for clarity.
Consider local vars used by a call to be conservative (SPIR-V has
such cases).
Comment and assert the assumption that stores and copies are
always to a deref that ends with a vector or scalar.
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
This peephole optimization looks for a series of load/store_deref or
copy_deref instructions that copy an array from one variable to another
and turns it into a copy_deref that copies the entire array. The
pattern it looks for is extremely specific but it's good enough to pick
up on the input array copies in DXVK and should also be able to pick up
the sequence generated by spirv_to_nir for a OpLoad of a large composite
followed by OpStore. It can always be improved later if needed.
Reviewed-by: Caio Marcelo de Oliveira Filho <caio.oliveira@intel.com>
This pass doesn't really do much now because nir_lower_vars_to_ssa can
already see through structures and considers them to be "split". This
pass exists to help other passes more easily see through structure
variables. If a back-end does implement arrays using scratch or
indirects on registers, having more smaller arrays is likely to have
better memory efficiency.
Reviewed-by: Caio Marcelo de Oliveira Filho <caio.oliveira@intel.com>
v2: ignore names on purpose, for consistency with other places where
we are doing the same (Alejandro)
v3: changes proposed by Timothy Arceri, implemented by Alejandro Piñeiro:
* Remove redundant 'struct active_xfb_varying'
* Update several comments, including spec quotes if needed
* Rename struct 'active_xfb_varying_array' to 'active_xfb_varyings'
* Rename variable 'array' to 'active_varyings'
* Replace one if condition for an assert (<MAX_FEEDBACK_BUFFERS)
* Remove BufferMode initialization (was already done)
v4: simplify output pointer handling (Timothy)
Signed-off-by: Neil Roberts <nroberts@igalia.com>
Signed-off-by: Alejandro Piñeiro <apinheiro@igalia.com>
Reviewed-by: Timothy Arceri <tarceri@itsqueeze.com>
Now that the elements version handles both cases, remove the
non-elements version.
Reviewed-by: Eric Anholt <eric@anholt.net>
Reviewed-by: Thomas Helland <thomashelland90@gmail.com>
also move some of the GLSL builtins over we will need for implementing
some OpenCL builtins
v2: replace NIR_IMM_FP by nir_imm_floatN_t in ported code
fix up changes caused by swizzle rework
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
Signed-off-by: Karol Herbst <kherbst@redhat.com>
This is mostly just a straight-forward conversion of
link_assign_atomic_counter_resources to C directly using nir variables
instead of GLSL IR variables.
It is based on the version of link_assign_atomic_counter_resources in
6b8909f2d1. I’m noting this here to make it easier to track changes
and keep the NIR version up-to-date.
Reviewed-by: Timothy Arceri <tarceri@itsqueeze.com>
This pass searches for reasonably large local variables which can be
statically proven to be constant and moves them into shader constant
data. This is especially useful when large tables are baked into the
shader source code because they can be moved into a UBO by the driver to
reduce register pressure and make indirect access cheaper.
v2 (Jason Ekstrand):
- Use a size/align function to ensure we get the right alignments
- Use the newly added deref offset helpers
Reviewed-by: Timothy Arceri <tarceri@itsqueeze.com>
Reviewed-by: Iago Toral Quiroga <itoral@igalia.com>
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
It's only used by the ir3 stand-alone compiler and Rob said we could
delete it.
Acked-by: Rob Clark <robdclark@gmail.com>
Acked-by: Bas Nieuwenhuizen <bas@basnieuwenhuizen.nl>
Acked-by: Dave Airlie <airlied@redhat.com>
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Signed-off-by: Rob Clark <robdclark@gmail.com>
Acked-by: Rob Clark <robdclark@gmail.com>
Acked-by: Bas Nieuwenhuizen <bas@basnieuwenhuizen.nl>
Acked-by: Dave Airlie <airlied@redhat.com>
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
To simplify the transition, and make things bisectable, split out a
legacy copy or lower_samplers. This way the i965 and gallium drivers
can independently switch over to deref instructions.
Since the lower_samplers_as_deref pass is only used by gallium drivers,
it can be converted in lock-step with moving the lower_deref_instrs
pass, and so does not need a corresponding _legacy clone.
This legacy pass will be removed in a future commit.
Signed-off-by: Rob Clark <robdclark@gmail.com>
Acked-by: Rob Clark <robdclark@gmail.com>
Acked-by: Bas Nieuwenhuizen <bas@basnieuwenhuizen.nl>
Acked-by: Dave Airlie <airlied@redhat.com>
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
This adds a concept of "members" to a variable with an interface type.
It allows you to specify the full variable data for each member of the
interface instead of once for the variable. We also add a lowering pass
to lower those variables to a sequence of variables and rewrite all the
derefs accordingly.
Acked-by: Rob Clark <robdclark@gmail.com>
Acked-by: Bas Nieuwenhuizen <bas@basnieuwenhuizen.nl>
Acked-by: Dave Airlie <airlied@redhat.com>
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
This commit introduces a new nir_deref.h header for helpers that are
less common and really only needed by a few heavy-duty passes. In this
header is a new struct for representing a full deref path which can be
walked in either direction.
v2 (Jason Ekstrand):
- Assert that deref != NULL (Caio)
- Fill _short_path with 0xdeadbeef in debug builds when not used (Caio)
- Make nir_deref_path a typedef (Rob)
Reviewed-by: Caio Marcelo de Oliveira Filho <caio.oliveira@intel.com>
Acked-by: Rob Clark <robdclark@gmail.com>
Acked-by: Bas Nieuwenhuizen <bas@basnieuwenhuizen.nl>
Acked-by: Dave Airlie <airlied@redhat.com>
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
This commit adds a pass for lowering deref instructions to deref chains
as well as some smaller helpers to ease the transition.
Reviewed-by: Caio Marcelo de Oliveira Filho <caio.oliveira@intel.com>
Acked-by: Rob Clark <robdclark@gmail.com>
Acked-by: Bas Nieuwenhuizen <bas@basnieuwenhuizen.nl>
Acked-by: Dave Airlie <airlied@redhat.com>
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
This function is equivalent to the linker.cpp
build_program_resource_list() but will extract the resources from NIR
shaders instead.
For now, only uniforms and program inputs are implemented.
v2: move from compiler/nir to compiler/glsl (Timothy Arceri)
v3: remove support for inputs, that is still WIP (spotted by Timothy
Arceri)
Signed-off-by: Eduardo Lima <elima@igalia.com>
Signed-off-by: Alejandro Piñeiro <apinheiro@igalia.com>
Reviewed-by: Timothy Arceri <tarceri@itsqueeze.com>
So it could be used by the GLSL and NIR linker.
v2: (Timothy Arceri)
* Moved from compiler to compiler/glsl
* Method renamed to link_util_add_program_resource
Reviewed-by: Timothy Arceri <tarceri@itsqueeze.com>
This is based on link_uniform_initializers.cpp.
v2: move from compiler/nir to compiler/glsl (Timothy Arceri)
Reviewed-by: Timothy Arceri <tarceri@itsqueeze.com>
This function will be the entry point for linking the uniforms from
the nir_shader objects associated with the gl_linked_shaders of a
program.
This patch includes initial support for linking uniforms from NIR
shaders. It is tailored for the ARB_gl_spirv needs, and it is far from
complete, but it should handle most cases of uniforms, array
uniforms, structs, samplers and images.
There are some FIXMEs related to specific features that will be
implemented in following patches, like atomic counters, UBOs and
SSBOs.
Also, note that ARB_gl_spirv makes mandatory explicit location for
normal uniforms, so this code only handles uniforms with explicit
location. But there are cases, like uniform atomic counters, that
doesn't have a location from the OpenGL point of view (they have a
binding), but that Mesa assign internally a location. That will be
handled on following patches.
A nir_linker.h file is also added. More NIR-linking related API will
be added in subsequent patches and those will include stuff from Mesa,
so reusing nir.h didn't seem a good idea.
v2: move from compiler/nir to compiler/glsl (Timothy Arceri)
v3: sets var->driver.location if the uniform was found from a previous
stage (Neil Roberts).
Signed-off-by: Eduardo Lima <elima@igalia.com>
Signed-off-by: Neil Roberts <nroberts@igalia.com
Signed-off-by: Alejandro Piñeiro <apinheiro@igalia.com>
Reviewed-by: Timothy Arceri <tarceri@itsqueeze.com>
Linker utilities common to the GLSL IR and NIR linker (the latter to
be used for ARB_gl_spirv).
We need to move it to a new header as the NIR linker doesn't need to
know about ir_variable, and others, included at linker.h.
v2: move from src/compiler to src/compiler/glsl (Timothy Arceri)
Reviewed-by: Timothy Arceri <tarceri@itsqueeze.com>
Run this pass late (after opt loop) to move load_const instructions back
into the basic blocks which use the result, in cases where a load_const
is only consumed in a single block.
This helps reduce register usage in cases where the backend driver
cannot lower the load_const to a uniform.
Signed-off-by: Rob Clark <robdclark@gmail.com>
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
This is based on the glsl/lower_instructions.cpp implementation, but
should be much more readable.
Reviewed-by: Matt Turner <mattst88@gmail.com>
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
