Commit graph

20 commits

Author SHA1 Message Date
Faith Ekstrand
53294de682 nir: Take a nir_def * in nir_phi_instr_add_src()
Reviewed-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/24729>
2023-08-18 01:00:14 +00:00
Faith Ekstrand
4695bebc79 nir: Drop nir_dest
Instead, we replace every use of it with nir_def.  Most of this commit
was generated by sed:

   sed -i -e 's/dest.ssa/def/g' src/**/*.h src/**/*.c src/**/*.cpp

A few manual fixups were required in lima and the nir_legacy code.

Acked-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/24674>
2023-08-14 21:22:53 +00:00
Faith Ekstrand
ed9affa02f nir: Drop most instances of nir_ssa_dest_init()
Generated using the following two semantic patches:

    @@
    expression I, J, NC, BS;
    @@

    -nir_ssa_dest_init(I, &J->dest, NC, BS);
    +nir_def_init(I, &J->dest.ssa, NC, BS);

    @@
    expression I, J, NC, BS;
    @@

    -nir_ssa_dest_init(I, &J->dest.dest, NC, BS);
    +nir_def_init(I, &J->dest.dest.ssa, NC, BS);

Acked-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/24658>
2023-08-13 17:12:52 +00:00
Alyssa Rosenzweig
09d31922de nir: Drop "SSA" from NIR language
Everything is SSA now.

   sed -e 's/nir_ssa_def/nir_def/g' \
       -e 's/nir_ssa_undef/nir_undef/g' \
       -e 's/nir_ssa_scalar/nir_scalar/g' \
       -e 's/nir_src_rewrite_ssa/nir_src_rewrite/g' \
       -e 's/nir_gather_ssa_types/nir_gather_types/g' \
       -i $(git grep -l nir | grep -v relnotes)

   git mv src/compiler/nir/nir_gather_ssa_types.c \
          src/compiler/nir/nir_gather_types.c

   ninja -C build/ clang-format
   cd src/compiler/nir && find *.c *.h -type f -exec clang-format -i \{} \;

Signed-off-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
Acked-by: Faith Ekstrand <faith.ekstrand@collabora.com>
Acked-by: Emma Anholt <emma@anholt.net>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/24585>
2023-08-12 16:44:41 -04:00
Alyssa Rosenzweig
01e9ee79f7 nir: Drop unused name from nir_ssa_dest_init
Since 624e799cc3 ("nir: Drop nir_ssa_def::name and nir_register::name"), SSA
defs don't have names, making the name argument unused. Drop it from the
signature and fix the call sites. This was done with the help of the following
Coccinelle semantic patch:

    @@
    expression A, B, C, D, E;
    @@

    -nir_ssa_dest_init(A, B, C, D, E);
    +nir_ssa_dest_init(A, B, C, D);

Signed-off-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
Reviewed-by: Timur Kristóf <timur.kristof@gmail.com>
Reviewed-by: Emma Anholt <emma@anholt.net>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/23078>
2023-05-17 23:46:16 +00:00
Ian Romanick
72a9d12c96 nir/tests: Port almost all loop_analyze tests to new macro-based infastructure
The one test that remains would have an automatically generated name
that would conflict with another test. This test is also a little
special (per the comment in the test), so it's probably best to leave it
separate anyway.

Reviewed-by: Timothy Arceri <tarceri@itsqueeze.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/3445>
2023-04-06 23:50:27 +00:00
Yevhenii Kolesnikov
9427aaeab7 nir/loop_analyze: Determine iteration counts for more kinds of loops
If loop iterator is incremented with something other than regular
addition, it would be more error prone to calculate the number of
iterations theoretically. What we can do instead, is try to emulate the
loop, and determine the number of iterations empirically.

These operations are covered:
 - imul
 - fmul
 - ishl
 - ishr
 - ushr

Also add unit tests for loop unrollment.

Improves performance of Aztec Ruins (sixonix
gfxbench5.aztec_ruins_vk_high) by -1.28042% +/- 0.498555% (N=5) on Intel
Arc A770.

v2 (idr): Rebase on 3 years. :( Use nir_phi_instr_add_src in the test
cases.

v3 (idr): Use try_eval_const_alu in to evaluate loop termination
condition in get_iteration_empirical. Also restructure the loop
slightly. This fixed off by one iteration errors in "inverted" loop
tests (e.g., nir_loop_analyze_test.ushr_ieq_known_count_invert_31).

v4 (idr): Use try_eval_const_alu in to evaluate induction variable
update in get_iteration_empirical. This fixes non-commutative update
operations (e.g., shifts) when the induction varible is not the first
source. This fixes the unit test
nir_loop_analyze_test.ishl_rev_ieq_infinite_loop_unknown_count.

v5 (idr): Fix _type parameter for fadd and fadd_rev loop unroll
tests. Hopefully that fixes the failure on s390x. Temporarily disable
fmul. This works-around the revealed problem in
glsl-fs-loop-unroll-mul-fp64, and there were no shader-db or fossil-db
changes.

v6 (idr): Plumb max_unroll_iterations into get_iteration_empirical. I
was going to do this, but I forgot. Suggested by Tim.

v7 (idr): Disable fadd tests on s390x. They fail because S390 is weird.

Almost all of the shaders affected (OpenGL or Vulkan) are from gfxbench
or geekbench. A couple shaders in Deus Ex (OpenGL), Dirt Rally (OpenGL),
Octopath Traveler (Vulkan), and Rise of the Tomb Raider (Vulkan) are
helped.

The lost / gained shaders in OpenGL are an Aztec Ruins shader that goes
from SIMD16 to SIMD8. The spills / fills affected are in a single Aztec
Ruins (Vulkan) compute shader.

shader-db results:

Skylake, Ice Lake, and Tiger Lake had similar results. (Tiger Lake shown)
total loops in shared programs: 5514 -> 5470 (-0.80%)
loops in affected programs: 62 -> 18 (-70.97%)
helped: 37 / HURT: 0

LOST:   2
GAINED: 2

Haswell and Broadwell had similar results. (Broadwell shown)
total loops in shared programs: 5346 -> 5298 (-0.90%)
loops in affected programs: 66 -> 18 (-72.73%)
helped: 39 / HURT: 0

fossil-db results:

Skylake, Ice Lake, and Tiger Lake had similar results. (Tiger Lake shown)
Instructions in all programs: 157374679 -> 157397421 (+0.0%)
Instructions hurt: 28

SENDs in all programs: 7463800 -> 7467639 (+0.1%)
SENDs hurt: 28

Loops in all programs: 38980 -> 38950 (-0.1%)
Loops helped: 28

Cycles in all programs: 7559486451 -> 7557455384 (-0.0%)
Cycles helped: 28

Spills in all programs: 11405 -> 11403 (-0.0%)
Spills helped: 1

Fills in all programs: 19578 -> 19588 (+0.1%)
Fills hurt: 1

Lost: 1

Signed-off-by: Yevhenii Kolesnikov <yevhenii.kolesnikov@globallogic.com>
Reviewed-by: Timothy Arceri <tarceri@itsqueeze.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/3445>
2023-04-06 23:50:27 +00:00
Yevhenii Kolesnikov
f051967f19 nir/loop_analyze: Track induction variables incremented by more operations
These operations are covered:

 - imul
 - fmul
 - ishl
 - ishr
 - ushr

The only cases that can be currently affected are those where the
calculated loop-trip count would be zero.

v2 (idr): Split out from original commit. Rebase on lots of other work.

v3 (idr): Move operand size assertion. This code only cares that the
operands have the same size for the iadd and fadd cases. In other
cases, such as shifts, the sizes may not match. Fixes assertion
failures in
tests/spec/arb_gpu_shader_int64/glsl-fs-loop-unroll-ishl-int64.shader_test.

No shader-db or fossil-db changes on any Intel platform.

Signed-off-by: Yevhenii Kolesnikov <yevhenii.kolesnikov@globallogic.com>
Reviewed-by: Timothy Arceri <tarceri@itsqueeze.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/3445>
2023-04-06 23:50:27 +00:00
Ian Romanick
99a7a6648d nir/loop_analyze: Change invert_cond instead of changing the condition
This ensures that scenarios like
nir_loop_analyze_test.iadd_inot_ilt_rev_known_count_5 don't regress in
the next commit. It also means we don't change float comparisons. These
are probably fine... but it still made me a little uneasy.

Reviewed-by: Timothy Arceri <tarceri@itsqueeze.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/3445>
2023-04-06 23:50:27 +00:00
Ian Romanick
2e942909c8 nir/tests: Add many loop analysis tests for induction variables modified by imul
Loop analysis doesn't currently treat values updated by multiplication
as induction variables. Future patches will change this.

Reviewed-by: Timothy Arceri <tarceri@itsqueeze.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/3445>
2023-04-06 23:50:27 +00:00
Ian Romanick
a210fcd9c7 nir/tests: Add more loop analysis tests for induction vars updated by shifts
These reverse the order of the comparison (e.g., -2 >= i vs i >= -2). I
split this into a separate commit because the previous commit was so
large.

Reviewed-by: Timothy Arceri <tarceri@itsqueeze.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/3445>
2023-04-06 23:50:27 +00:00
Ian Romanick
45518d2eba nir/tests: Add many loop analysis tests for induction vars updated by shifts
Loop analysis doesn't currently treat values updated by shifts as
induction variables. Future patches will change this.

v2: Don't use the contradiction ilt(x, INT_MIN).

v3: Delete some errant code in UNKNOWN_COUNT_TEST. Noticed by Tim.

Reviewed-by: Timothy Arceri <tarceri@itsqueeze.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/3445>
2023-04-06 23:50:27 +00:00
Ian Romanick
e444ed9210 nir/loop_analyze: Use nir_loop_variable::init_src instead of nir_basic_induction_var::def_outside_loop
These track the same information in a slightly different way. Since
nir_loop_variable::init_src is visible outside this module, it cannot
be eliminated.

As an intentional side effect, induction variables with constant
initializers will now have their nir_loop_induction_variable::init_src
field point to the load_const source. Previously this pointer would be
NULL.

v2: Update unit tests and commit message. Remove the now unused ind_var
variable in find_trip_count.

Reviewed-by: Caio Oliveira <caio.oliveira@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/21289>
2023-02-17 22:12:05 +00:00
Ian Romanick
1bc43c0778 nir/loop_analyze: Track induction variables with uniform increments
As an intentional side effect, induction variables with constant
increments will now have their nir_loop_induction_variable::update_src
field point to the load_const source. Previously this pointer would be
NULL.

v2: Update unit tests and commit message.

Reviewed-by: Caio Oliveira <caio.oliveira@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/21289>
2023-02-17 22:12:05 +00:00
Ian Romanick
c26d356dd5 nir/tests: Add tests for nir_loop_info::induction_vars tracking
Later commits in this MR will change the way some data is track, and
these tests will verify this behavior change.

Reviewed-by: Caio Oliveira <caio.oliveira@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/21289>
2023-02-17 22:12:05 +00:00
Ian Romanick
168e54f7e3 nir/tests: Add tests for "inverted" loops
A couple basic tests for loops with the exit condition after the
increment. In compiler literature, the optimization that moves the exit
condition from the top to the bottom is called "loop inversion."

v2: Pass parameters to loop_builder_invert using a struct. Add a comment
describing the loop being constructed to loop_builder_invert. Both
suggested by Caio.

Reviewed-by: Caio Oliveira <caio.oliveira@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/21289>
2023-02-17 22:12:05 +00:00
Ian Romanick
ffe0db099c nir/tests: Refactor creation of loops for loop_analyze test cases
Inspired heavily by the work by Yevhenii Kolesnikov in the original
versions of !3445.

v2: Pass parameters to loop_builder using a struct. Add a comment
describing the loop being constructed to loop_builder. Both suggested by
Caio.

v3: mscv C++ designated initializer lolz.

Reviewed-by: Caio Oliveira <caio.oliveira@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/21289>
2023-02-17 22:12:05 +00:00
Ian Romanick
f75c83c4aa nir/loop_analyze: Fix get_iteration for nir_op_fneu
Consider the loop:

    float i = 0.0;
    while (true) {
       if (i != 0.0)
          break;

       i = i + 1.0;
    }

This loop clearly executes exactly one time.

Some trickery is necessary to handle cases where the initial loop value
is very large and the increment is, by comparison, very small.  From the
fenu_once test case,

    float i = -604462909807314587353088.0;
    while (true) {
       if (i != -604462909807314587353088.0)
          break;

       i = i + 36028797018963968.0;
    }

This loop should also execute exactly once, but this is much more
challenging to calculate due to precision issues.

Going towards smaller magnitude (i.e., adding a small positive value to
a large negative value) requires a smaller delta to make a difference
than going towards a larger magnitude. For this reason,
-604462909807314587353088.0 + 36028797018963968.0 !=
-604462909807314587353088.0, but -604462909807314587353088.0 +
-36028797018963968.0 == -604462909807314587353088.0. Math class is
tough.

No changes in shader-db or fossil-db.

v2: Fix major bug in checking result of the eval_const_binop(nir_op_feq,
...) discovered while developing fneu_once_easy unit test. Fix a typo in
the comment just above that. Add fneu_once_easy test.

v3: Skip the iteration count adjustment tests for nir_op_fenu and
nir_op_ine. Since the iteration count is either 1 or unknown, all this
function can do is add numerical error. Add fenu_once tests.

v4: Change the initial value in the fneu_once test from large positive
to large negative. Change check in get_iteration from nir_op_fsub to
nir_op_fadd. Both changes from discussion with M Henning. Also add some
more explanation in fneu_once.

v5: Rename test cases.

Fixes: 6772a17acc ("nir: Add a loop analysis pass")
Reviewed-by: Timothy Arceri <tarceri@itsqueeze.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/19732>
2022-11-22 03:18:54 +00:00
Ian Romanick
d9f014401b nir/loop_analyze: Fix get_iteration for nir_op_ine
I discovered this problem because adding an algebraic transformation to
convert some uge and ult to ieq or ine caused a couple loops to stop
unrolling. Consider the loop:

    uint i = 0;
    while (true) {
       if (i >= 1)
          break;

       i++;
    }

This loop clearly executes exactly one time. Note that uge(x, 1) is
equivalent to ine(x, 0). Changing the condition to 'if (i != 0)' will
also execute exactly one time.

In the added test cases, uge_once correctly get an exact loop trip count
of 1. Without the changes to nir_loop_analyze.c, the ine_once case
detects a maximum loop trip count of zero and does not get an exact loop
trip count.

No changes in shader-db or fossil-db.

v2: Move nir_op_fneu changes to a separate commit.

v3: Rename test cases.

Fixes: 6772a17acc ("nir: Add a loop analysis pass")
Reviewed-by: Timothy Arceri <tarceri@itsqueeze.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/19732>
2022-11-22 03:18:54 +00:00
Ian Romanick
dbad33da16 nir/loop_analyze: Add basic unit test framework
This test comes from a comment in the loop analysis code.

The ine_zero test checks that zero iteration loops involving ine are
correctly identified.

v2: Add ine_zero test. Suggested by Tim.

v3: Rename test cases.

Reviewed-by: Timothy Arceri <tarceri@itsqueeze.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/19732>
2022-11-22 03:18:54 +00:00