Previously can_do_source_mods was used to determine whether a value with
a source modifier or a value from a scalar source (e.g., a uniform)
could be copy propagated. The former is a superset of the latter, so
this always produces correct results, but it is overly restrictive. For
example, a BFI instruction can't have source modifiers, but it can have
scalar sources.
This was originally authored to prevent a small number of shader-db
regressions in a commit that marked SHR has not being able to have
source modifiers. That commit has since been dropped in favor of a
different method.
v2: Refactor register region restriction detection to a helper function.
Suggested by Jason.
No fossil-db changes on any Intel platform.
All Gen7+ platforms had similar results. (Ice Lake shown)
total instructions in shared programs: 20039111 -> 20038943 (<.01%)
instructions in affected programs: 31736 -> 31568 (-0.53%)
helped: 104
HURT: 0
helped stats (abs) min: 1 max: 9 x̄: 1.62 x̃: 1
helped stats (rel) min: 0.30% max: 0.88% x̄: 0.45% x̃: 0.42%
95% mean confidence interval for instructions value: -2.03 -1.20
95% mean confidence interval for instructions %-change: -0.47% -0.42%
Instructions are helped.
total cycles in shared programs: 980309750 -> 980308897 (<.01%)
cycles in affected programs: 591078 -> 590225 (-0.14%)
helped: 70
HURT: 26
helped stats (abs) min: 2 max: 622 x̄: 23.94 x̃: 4
helped stats (rel) min: <.01% max: 2.85% x̄: 0.33% x̃: 0.12%
HURT stats (abs) min: 2 max: 520 x̄: 31.65 x̃: 6
HURT stats (rel) min: 0.02% max: 2.45% x̄: 0.34% x̃: 0.15%
95% mean confidence interval for cycles value: -26.41 8.64
95% mean confidence interval for cycles %-change: -0.27% -0.03%
Inconclusive result (value mean confidence interval includes 0).
No shader-db changes on earlier Intel platforms.
Reviewed-by: Anuj Phogat anuj.phogat@gmail.com [v1]
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/9237>
I meant to do this years ago when I first added SHADER_OPCODE_SEND. At
the time, the only use for the extended descriptor was bindless handles
which were always one thing and never non-constant. However, it doesn't
actually require any extra instructions because we have to OR in ex_mlen
anyway.
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/8748>
This pulls out the i965 IR definitions into a separate file and leaves
the top-level backend_shader structure and back-end compiler entry
points in brw_shader.h. The purpose is to keep things tidy and
prevent a nasty circular dependency between brw_cfg.h and
brw_shader.h. The logical dependency between these data structures
looks like:
backend_shader (brw_shader.h) -> cfg_t (brw_cfg.h)
-> bblock_t (brw_cfg.h) -> backend_instruction (brw_shader.h)
This circular header dependency is currently resolved by using forward
declarations of cfg_t/bblock_t in brw_shader.h and having brw_cfg.h
include brw_shader.h, which seems backwards and won't work at all when
the forward declarations of cfg_t/bblock_t are no longer sufficient in
a future commit.
Reviewed-by: Matt Turner <mattst88@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/4012>
