We already detect any incomplete deref chains (where the deref is used
for something other than another deref or a load/store) and flag the
variable as used thanks to deref_used_for_not_store. All that's left to
do is to properly skip casts when cleaning up.
Reviewed-by: Alejandro Piñeiro <apinheiro@igalia.com>
Reviewed-by: Caio Marcelo de Oliveira Filho <caio.oliveira@intel.com>
This pass is used when, for instance, we lazily change the mode of
variables rather than replacing the variable with a new one. Since we
only do this in cases where we know we have full deref chains, it's ok
to just skip them in fixup_deref_modes.
Reviewed-by: Alejandro Piñeiro <apinheiro@igalia.com>
Reviewed-by: Caio Marcelo de Oliveira Filho <caio.oliveira@intel.com>
The code which constructs deref paths already gives you the path
starting at the nearest deref_cast or deref_var. All we need to do for
casts is handle the case where the start of the path isn't a deref_var.
For ptr_as_array derefs, we just bail if we have any after the
divergence point between the two derefs. We may be able to do better in
the future but this works for now.
Reviewed-by: Alejandro Piñeiro <apinheiro@igalia.com>
Reviewed-by: Caio Marcelo de Oliveira Filho <caio.oliveira@intel.com>
When handling casts, we can't blindly propagate the parent of a cast
into a ptr_as_array deref because doing so might loose the stride
information from the cast. Instead, before we can propagate into
ptr_as_array derefs, we need to check that the cast is a cast of an
array deref and that the stride matches. For other types of derefs, we
can continue to propagate casts as normal because they don't need the
stride. We also add an optimization which can combine a ptr_as_array
deref with it parent if it is also an array deref of some form.
Reviewed-by: Alejandro Piñeiro <apinheiro@igalia.com>
Reviewed-by: Caio Marcelo de Oliveira Filho <caio.oliveira@intel.com>
These correspond directly to SPIR-V's OpPtrAccessChain. As such, they
treat whatever their parent gives them as if it's the first element in
some array and dereferences that array. If the parent is, itself, an
array deref, then the two indices can just be added together to get the
final array deref. However, it can also be used in cases where what you
have is a dereference to some random vec2 value somewhere. In this
case, we require a cast before the ptr_as_array and use the ptr_stride
field in the cast to provide a stride for the ptr_as_array derefs.
Reviewed-by: Alejandro Piñeiro <apinheiro@igalia.com>
Reviewed-by: Caio Marcelo de Oliveira Filho <caio.oliveira@intel.com>
We're going to want to do more deref optimizations going forward and
this gives us a central place to do them. Also, cast propagation will
get a bit more complicated with the addition of ptr_as_array derefs.
Reviewed-by: Alejandro Piñeiro <apinheiro@igalia.com>
Reviewed-by: Caio Marcelo de Oliveira Filho <caio.oliveira@intel.com>
Instead of just storing the decorations in the vtn_type, propagate them
all the way through to the glsl_type. For array strides, this means we
need to handle them earlier so we break array stride handling into it's
own function and explicitly call it for both pointer and array types.
Due to type deduplication in the SPIR-V, we may have explicit layout
decorations on all sorts of types that don't actually want them. In
order to prevent these leaking into unfortunate places in NIR, we
explicitly strip them off before creating NIR variables and when casting
pointers to non-external memory.
Reviewed-by: Alejandro Piñeiro <apinheiro@igalia.com>
SPIR-V allows for matrix and array types to be decorated with explicit
byte stride decorations and matrix types to be decorated row- or
column-major. This commit adds support to glsl_type to encode this
information. Because this doesn't work nicely with std430 and std140
alignments, we add asserts to ensure that we don't use any of the std430
or std140 layout functions with explicitly laid out types.
In SPIR-V, the layout information for matrices is applied to the parent
struct member instead of to the matrix type itself. However, this is
gets rather clumsy when you're walking derefs trying to compute offsets
because, the moment you hit a matrix, you have to crawl back the deref
chain and find the struct. Instead, we take the same path here as we've
taken in spirv_to_nir and put the decorations on the matrix type itself.
This also subtly adds support for strided vector types. These don't
come up in SPIR-V directly but you can get one as the result of taking a
column from a row-major matrix or a row from a column-major matrix.
Reviewed-by: Alejandro Piñeiro <apinheiro@igalia.com>
This is C++ so we can just poke at the fields of glsl_type if we wish
and calling get_instance is way easier and more reliable than handling
each instance separately. While we're at it, we re-arrange the base
type labels to match the enum order and add 8-bit type support.
Reviewed-by: Alejandro Piñeiro <apinheiro@igalia.com>
Reviewed-by: Caio Marcelo de Oliveira Filho <caio.oliveira@intel.com>
It was added in bce6f99875 even though it's completely redundant with
glsl_array_type().
Reviewed-by: Alejandro Piñeiro <apinheiro@igalia.com>
Reviewed-by: Caio Marcelo de Oliveira Filho <caio.oliveira@intel.com>
Previously, NIR had a single nir_var_uniform mode used for atomic
counters, UBOs, samplers, images, and normal uniforms. This commit
splits this into nir_var_uniform and nir_var_ubo where nir_var_uniform
is still a bit of a catch-all but the nir_var_ubo is specific to UBOs.
While we're at it, we also rename shader_storage to ssbo to follow the
convention.
We need this so that we can distinguish between normal uniforms and UBO
access at the deref level without going all the way back variable and
seeing if it has an interface type.
Reviewed-by: Alejandro Piñeiro <apinheiro@igalia.com>
Reviewed-by: Caio Marcelo de Oliveira Filho <caio.oliveira@intel.com>
I have no idea how shader_storage made it into the list of banned
variable modes for stores but it clearly should be allowed. This only
doesn't cause us a problem today because we never actually use derefs on
shader_storage variables.
Reviewed-by: Alejandro Piñeiro <apinheiro@igalia.com>
Reviewed-by: Caio Marcelo de Oliveira Filho <caio.oliveira@intel.com>
This doesn't currently change anything because array indices are
required to be 32 bits and all derefs are also 32 bits. However, we
will one day have 64-bit derefs for OpenCL.
Reviewed-by: Alejandro Piñeiro <apinheiro@igalia.com>
Reviewed-by: Caio Marcelo de Oliveira Filho <caio.oliveira@intel.com>
We already had code in link_as_ssa to handle bit sizes; we just need to
use it. While we're at it we clean up link_as_ssa a bit and add an
explicit bit_size parameter in preparation for a day when we have derefs
that aren't 32 bit.
Cc: mesa-stable@lists.freedesktop.org
Reviewed-by: Alejandro Piñeiro <apinheiro@igalia.com>
Reviewed-by: Caio Marcelo de Oliveira Filho <caio.oliveira@intel.com>
This simplifies our deref handling by emitting the actual NIR deref
instructions on-the-fly instead of of building up a deref chain and then
emitting them at the last moment. In order for this to work with the
parts of the compiler that assume they can chase deref chains, we have
to run nir_rematerialize_derefs_in_use_blocks_impl to put the derefs
back in the right places. Otherwise, in cases such as loop continues
where the SPIR-V blocks are not in the same order as the NIR blocks, we
may end up with a deref chain with a parent that does not dominate it's
child and nir_repair_ssa_impl will insert phis in the deref chain.
Reviewed-by: Alejandro Piñeiro <apinheiro@igalia.com>
Reviewed-by: Caio Marcelo de Oliveira Filho <caio.oliveira@intel.com>
The SPIR-V spec was recently updated to clarify that array indices are
treated as signed integers.
Cc: mesa-stable@lists.freedesktop.org
Reviewed-by: Alejandro Piñeiro <apinheiro@igalia.com>
Reviewed-by: Caio Marcelo de Oliveira Filho <caio.oliveira@intel.com>
This crops up both in the actual SPIR-V VectorInsert/Extract opcodes as
well as various places where we deal with vector derefs.
Cc: mesa-stable@lists.freedesktop.org
Reviewed-by: Alejandro Piñeiro <apinheiro@igalia.com>
Reviewed-by: Caio Marcelo de Oliveira Filho <caio.oliveira@intel.com>
They can be handled exactly the same as arrays, we just need to handle
the base type correctly in the switches.
Fixes: a45b6fb452 "spirv: Pass SSA values through functions"
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=109204
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
Reviewed-by: Samuel Pitoiset <samuel.pitoiset@gmail.com>
These days, we have two sampler lowering passes. The newer one,
gl_nir_lower_samplers_as_deref, is used by radeonsi. It rewrites
variables to drop structures out of sampler deref chains, to make
life simpler. It then sets var->data.binding for non-bindless
sampler and image variables based on the GL uniform storage's
opaque index values.
The older one converts sampler deref chains (nir_tex_src_texture_deref)
to a numerical offset (nir_tex_src_texture_offset). It also stores the
constant-valued portion of that number in tex->texture_index, making
life really simple for drivers that don't support indirects. It too
pokes at GL uniform storage's opaque index values.
Logically, we can do the first pass (simplify derefs, set bindings)
then the second (turn derefs to offsets, set texture_index). This
patch does exactly that, eliminating some redundancy (only one pass
has to poke at GL uniform storage), and gaining proper var->data.binding
values for drivers using the full lowering.
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
Acked-by: Jason Ekstrand <jason@jlekstrand.net>
We recurse to remove structures, and at each step, re-modify the
resulting type for our link in the deref chain. For arrays, the
result of recursion is the new underlying type - so we wrap it with
the array dimensionality again. For structs, we want to simply use
the new underlying type, skipping the struct altogether.
The correct way to do this is to do nothing at all. Previously, we
had reset type to next->type, which is the /old/ field type, not the
new field type we obtained by recursing. This undid our recursive work.
Fixes about 338 tests with nested structs, such as:
dEQP-GLES2.functional.uniform_api.value.initial.get_uniform.nested_structs_arrays.sampler2D_samplerCube_fragment
Note that currently only radeonsi uses this pass, and NIR support is
disabled there by default, so the breakage was likely not seen by most
people. The next commit uses this pass for more drivers, so this fix
prevents regressions from that change.
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
Acked-by: Jason Ekstrand <jason@jlekstrand.net>
I've been doing this in the nir-to-vir and nir-to-qir backends of v3d and
vc4, but nir could potentially do some useful stuff for us (like avoiding
unpack/repacks) if we give it the information.
v2: Skip lowering for txs/query_levels
v3: Fix a crash on old-style shadow
v4: Rename to tex_packing, use nir_format_unpack_sint/uint helpers, pack
the enum.
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
When copy_prop_vars also took care of dead write handling, intrin was
used as part of store_to_entry. Now it isn't, so this assignment
isn't used really used. Add a comment clarifying what happens to
intrin.
Fixes: 4dfa7adc10 "nir: Remove handling of dead writes from copy_prop_vars"
Reviewed-by: Jordan Justen <jordan.l.justen@intel.com>
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
Commit 27f1298b9d ("glsl/linker: validate attribute aliasing before optimizations")
forgot to complete the documentation.
Cc: Tapani Pälli <tapani.palli@intel.com>
Signed-off-by: Andres Gomez <agomez@igalia.com>
Reviewed-by: Tapani Pälli <tapani.palli@intel.com>
After trying multiple times to merge if-statements with phis
between them I've come to the conclusion that it cannot be done
without regressions. The problem is for some shaders we end up
with a whole bunch of phis for the merged ifs resulting in
increased register pressure.
So this patch just merges ifs that have no phis between them.
This seems to be consistent with what LLVM does so for radeonsi
we only see a change (although its a large change) in a single
shader.
Shader-db results i965 (SKL):
total instructions in shared programs: 13098176 -> 13098152 (<.01%)
instructions in affected programs: 1326 -> 1302 (-1.81%)
helped: 4
HURT: 0
total cycles in shared programs: 332032989 -> 332037583 (<.01%)
cycles in affected programs: 60665 -> 65259 (7.57%)
helped: 0
HURT: 4
The cycles estimates reported by shader-db for i965 seem inaccurate
as the only difference in the final code is the removal of the
redundent condition evaluations and jumps.
Also the biggest code reduction (~7%) for radeonsi was in a tomb
raider tressfx shader but for some reason this does not get merged
for i965.
Shader-db results radeonsi (VEGA):
Totals from affected shaders:
SGPRS: 232 -> 232 (0.00 %)
VGPRS: 164 -> 164 (0.00 %)
Spilled SGPRs: 59 -> 59 (0.00 %)
Spilled VGPRs: 0 -> 0 (0.00 %)
Private memory VGPRs: 0 -> 0 (0.00 %)
Scratch size: 0 -> 0 (0.00 %) dwords per thread
Code Size: 14584 -> 13520 (-7.30 %) bytes
LDS: 0 -> 0 (0.00 %) blocks
Max Waves: 13 -> 13 (0.00 %)
Wait states: 0 -> 0 (0.00 %)
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
Makes debugging easier when we care about the deref chain and not the
deref instruction itself. To make it take a const pointer, constify
some of the static functions in nir_print.c.
Reviewed-by: Eric Anholt <eric@anholt.net>
The 16-bit polynomial execution doesn't meet Khronos precision requirements.
Also, the half-float denorm range starts at 2^(-14) and with asin taking input
values in the range [0, 1], polynomial approximations can lead to flushing
relatively easy.
An alternative is to use the atan2 formula to compute asin, which is the
reference taken by Khronos to determine precision requirements, but that
ends up generating too many additional instructions when compared to the
polynomial approximation. Specifically, for the Intel case, doing this
adds +41 instructions to the program for each asin/acos call, which looks
like an undesirable trade off.
So for now we take the easy way out and fallback to using the 32-bit
polynomial approximation, which is better (faster) than the 16-bit atan2
implementation and gives us better precision that matches Khronos
requirements.
v2:
- Fallback to 32-bit using recursion (Jason).
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
v2:
- use nir_fadd_imm and nir_fmul_imm helpers (Jason)
v3:
- since we need to define one for fsub use it for fdiv too (Jason)
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
v2:
- fix huge_val for 16-bit, it was mean't to be 2^14 not 10^14.
v3:
- rebase on top of new bool sized opcodes
- use nir_b2f helper
- use nir_fmul_imm helper
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
v2:
- use nir_fadd_imm and nir_fmul_imm helpers (Jason)
- rebased on top of new sized boolean opcodes
- use nir_b2f helper
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
v2:
- use nir_fmul_imm and nir_fadd_imm helpers (Jason)
v3:
- missed one case where we need to replace nir_imm_float
with nir_imm_floatN_t (Jason)
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
This just cleans things up a little and make things more safe for
derefs.
Tested-by: Dieter Nützel <Dieter@nuetzel-hh.de>
Reviewed-by: Eric Anholt <eric@anholt.net>
This will be reused by the following patch.
Tested-by: Dieter Nützel <Dieter@nuetzel-hh.de>
Reviewed-by: Marek Olšák <marek.olsak@amd.com>
Reviewed-by: Eric Anholt <eric@anholt.net>
