In 9f3c595dfc, we attempted to handle casts in opt_find_array_copies
but missed a critical case. In particular, in the case where we begin
finding a copy but then encounter a cast, we need to discard everything
which might alias that cast.
Fixes: 9f3c595dfc "nir/find_array_copies: Handle cast derefs"
Reviewed-by: Caio Marcelo de Oliveira Filho <caio.oliveira@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/6871>
copy_deref for wildcard dereferences requires the same
arrays lengths otherwise it leads to a crash in optimizations
like 'nir_opt_copy_prop_vars' because these optimizations expect
'copy_deref' just for arrays with the same lengths.
v2: check was moved to 'try_match_deref' to fix aoa cases
(Jason Ekstrand <jason@jlekstrand.net>)
v3: -fixed comment
-the condition merged with other one
(Jason Ekstrand <jason@jlekstrand.net>)
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=111286
Signed-off-by: Andrii Simiklit <andrii.simiklit@globallogic.com>
When we detect a scalar/vector copy through load_deref/store_deref, we
have to be careful since those can bitcast an int to a float and
vice-versa even though copy_deref can't.
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=111251
Fixes: 156306e5e6 ("nir/find_array_copies: Handle wildcards and overlapping copies")
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Acked-by: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>
instr->type is the type of the array element, not the type of the array
being dereferenced. Rather than fishing out the parent type, just use
parent->num_children which should be the length plus 1. While we're here
add another assert for the issue fixed by the previous commit.
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=111251
Fixes: 156306e5e6 ("nir/find_array_copies: Handle wildcards and overlapping copies")
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
This commit rewrites opt_find_array_copies to be able to handle
an array copy sequence with other intervening operations in between. In
particular, this handles the case where we OpLoad an array of structs
and then OpStore it, which generates code like:
foo[0].a = bar[0].a
foo[0].b = bar[0].b
foo[1].a = bar[1].a
foo[1].b = bar[1].b
...
that wasn't recognized by the previous pass.
In order to correctly handle copying arrays of arrays, and in particular
to correctly handle copies involving wildcards, we need to use a tree
structure similar to lower_vars_to_ssa so that we can walk all the
partial array copies invalidated by a particular write, including
ones where one of the common indices is a wildcard. I actually think
that when factoring in the needed hashing/comparing code, a hash table
based approach wouldn't be a lot smaller anyways.
All of the changes come from tessellation control shaders in Strange
Brigade, where we're able to remove the DXVK-inserted copy at the
beginning of the shader. These are the result for radv:
Totals from affected shaders:
SGPRS: 4576 -> 4576 (0.00 %)
VGPRS: 13784 -> 5560 (-59.66 %)
Spilled SGPRs: 0 -> 0 (0.00 %)
Spilled VGPRs: 0 -> 0 (0.00 %)
Private memory VGPRs: 0 -> 0 (0.00 %)
Scratch size: 8696 -> 6876 (-20.93 %) dwords per thread
Code Size: 329940 -> 263268 (-20.21 %) bytes
LDS: 0 -> 0 (0.00 %) blocks
Max Waves: 330 -> 898 (172.12 %)
Wait states: 0 -> 0 (0.00 %)
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
Signed-off-by: Karol Herbst <kherbst@redhat.com>
Acked-by: Jason Ekstrand <jason@jlekstrand.net>
Reviewed-by: Eric Anholt <eric@anholt.net>
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Bas Nieuwenhuizen <bas@basnieuwenhuizen.nl>
the naming is a bit confusing no matter how you look at it. Within SPIR-V
"global" memory is memory accessible from all threads. glsl "global" memory
normally refers to shader thread private memory declared at global scope. As
we already use "shared" for memory shared across all thrads of a work group
the solution where everybody could be happy with is to rename "global" to
"private" and use "global" later for memory usually stored within system
accessible memory (be it VRAM or system RAM if keeping SVM in mind).
glsl "local" memory is memory only accessible within a function, while SPIR-V
"local" memory is memory accessible within the same workgroup.
v2: rename local to function as well
v3: rename vtn_variable_mode_local as well
Signed-off-by: Karol Herbst <kherbst@redhat.com>
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>
