This is when the copies actually happen, not at the branch.
fossil-db (gfx1100):
Totals from 1 (0.00% of 79332) affected shaders:
Instrs: 424 -> 423 (-0.24%)
CodeSize: 2172 -> 2168 (-0.18%)
Latency: 2899 -> 2896 (-0.10%)
Copies: 24 -> 23 (-4.17%)
Signed-off-by: Rhys Perry <pendingchaos02@gmail.com>
Reviewed-by: Timur Kristóf <timur.kristof@gmail.com>
Cc: mesa-stable
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/25244>
When an exec write isn't used but writes other registers
besides exec, and also reads exec (such as s_and_saveexec),
we would mistakenly delete the previous instruction that
writes the exec value that this instruction uses.
No Fossil DB changes on Rembrandt (GFX10.3).
Fixes: 0211e66f65
Closes: https://gitlab.freedesktop.org/mesa/mesa/-/issues/9036
Signed-off-by: Timur Kristóf <timur.kristof@gmail.com>
Reviewed-by: Georg Lehmann <dadschoorse@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/23576>
The branch instruction is no longer conditional when the targets are the
same, so the operand is not necessary and can be removed.
Reviewed-by: Daniel Schürmann <daniel@schuermann.dev>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/21493>
Verifying that the branch instruction reads exec is not actually
necessary because the pattern that we look for already implies that.
This prepares for the next commit which will remove the exec operand
from branches that have the same target. These branches will no
longer read exec, but they should still get the same optimization.
Reviewed-by: Daniel Schürmann <daniel@schuermann.dev>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/21493>
Don't eliminate an instruction that writes registers other than exec and scc.
It is possible that this is eg. an s_and_saveexec and the saved value is
used by a later branch.
Fixes: bc13049747
Reviewed-by: Daniel Schürmann <daniel@schuermann.dev>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/21493>
In a lot of situations the previous exec value was already copied from the
same registers that exec should be saved to. In that case we don't have to
insert an extra copy to save exec.
This breaks ssa but this pass is going out of ssa anyway.
Foz-DB Navi21:
Totals from 16129 (11.96% of 134913) affected shaders:
CodeSize: 128184044 -> 128054468 (-0.10%)
Instrs: 23902694 -> 23870325 (-0.14%)
Latency: 387124324 -> 387095955 (-0.01%); split: -0.01%, +0.00%
InvThroughput: 79949118 -> 79945859 (-0.00%); split: -0.01%, +0.00%
Copies: 1620768 -> 1588752 (-1.98%); split: -1.99%, +0.01%
Foz-DB Vega10:
Totals from 15546 (11.51% of 135041) affected shaders:
CodeSize: 120322524 -> 120200568 (-0.10%)
Instrs: 23448344 -> 23417855 (-0.13%)
Latency: 414018749 -> 413639289 (-0.09%); split: -0.09%, +0.00%
InvThroughput: 183819363 -> 183726539 (-0.05%); split: -0.05%, +0.00%
Copies: 2194937 -> 2164448 (-1.39%)
Signed-off-by: Georg Lehmann <dadschoorse@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/18528>
A situation where it doesn't match is probably not possible, so this
probably doesn't fix anything.
Signed-off-by: Rhys Perry <pendingchaos02@gmail.com>
Reviewed-by: Georg Lehmann <dadschoorse@gmail.com>
Reviewed-by: Timur Kristóf <timur.kristof@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/18077>
If this is true, then the only instruction the loops visit is
p_logical_end and the loops are no-ops.
Signed-off-by: Rhys Perry <pendingchaos02@gmail.com>
Reviewed-by: Georg Lehmann <dadschoorse@gmail.com>
Reviewed-by: Timur Kristóf <timur.kristof@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/18077>
We shouldn't remove a p_cbranch_nz branch in this situation.
Signed-off-by: Rhys Perry <pendingchaos02@gmail.com>
Reviewed-by: Georg Lehmann <dadschoorse@gmail.com>
Reviewed-by: Timur Kristóf <timur.kristof@gmail.com>
Fixes: b731be2e96 ("aco: Remove branch instruction when exec is constant non-zero.")
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/18077>
The isConstant() check isn't useful. If it's a constant, then the
physReg() check will fail.
Signed-off-by: Rhys Perry <pendingchaos02@gmail.com>
Reviewed-by: Georg Lehmann <dadschoorse@gmail.com>
Reviewed-by: Timur Kristóf <timur.kristof@gmail.com>
Fixes: baab6f18c9 ("aco: Optimize branching sequence during SSA elimination.")
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/18077>
This optimization was broken for two reasons:
- s_and_saveexec has two operands, the copy value and exec
- s_and_saveexec has an exec read, so exec_write_used will always be true
before we find branch_exec_val_idx
Foz-DB Navi21:
Totals from 31453 (23.31% of 134913) affected shaders:
CodeSize: 204831260 -> 204831156 (-0.00%)
Instrs: 38157117 -> 38157091 (-0.00%)
Latency: 533708882 -> 531211721 (-0.47%); split: -0.47%, +0.00%
InvThroughput: 107088408 -> 106719188 (-0.34%); split: -0.35%, +0.00%
Copies: 2326179 -> 2502490 (+7.58%)
Signed-off-by: Georg Lehmann <dadschoorse@gmail.com>
Reviewed-by: Timur Kristóf <timur.kristof@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/18049>
Inserting in the instructions vector may invalidate the exec_val reference,
so do that last.
Fixes: baab6f18c9 ("aco: Optimize branching sequence during SSA elimination.")
Signed-off-by: Timur Kristóf <timur.kristof@gmail.com>
Reviewed-by: Georg Lehmann <dadschoorse@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/18049>
Currently all usages of exec and vcc are hardcoded to use s2 regclass.
This commit makes it possible to use s1 in wave32 mode and
s2 in wave64 mode.
Signed-off-by: Timur Kristóf <timur.kristof@gmail.com>
Reviewed-by: Daniel Schürmann <daniel@schuermann.dev>
ACO (short for AMD Compiler) is a new compiler backend with the goal to replace
LLVM for Radeon hardware for the RADV driver.
ACO currently supports only VS, PS and CS on VI and Vega.
There are some optimizations missing because of unmerged NIR changes
which may decrease performance.
Full commit history can be found at
https://github.com/daniel-schuermann/mesa/commits/backend
Co-authored-by: Daniel Schürmann <daniel@schuermann.dev>
Co-authored-by: Rhys Perry <pendingchaos02@gmail.com>
Co-authored-by: Bas Nieuwenhuizen <bas@basnieuwenhuizen.nl>
Co-authored-by: Connor Abbott <cwabbott0@gmail.com>
Co-authored-by: Michael Schellenberger Costa <mschellenbergercosta@googlemail.com>
Co-authored-by: Timur Kristóf <timur.kristof@gmail.com>
Acked-by: Samuel Pitoiset <samuel.pitoiset@gmail.com>
Acked-by: Bas Nieuwenhuizen <bas@basnieuwenhuizen.nl>
