[Mesa-dev] [PATCH v3 00/13] TGSI: improved live range tracking, also including arrays

[Roland Scheidegger]

FWIW I'm not really qualified to review this, but this alleviates the
concerns I had some time ago about doing spilling for r600 before sb.
So this makes all sense to me.

Roland

Am 28.04.2018 um 21:30 schrieb Gert Wollny:
> this is another update of the series I've sent before. 
> 
> v3: 
>  - Add new test mesa/st/tests/meson.build
>  - rebase patches to latest HEAD
> 
> this is the merged version of two series [1] (TGSI: split, merge 
> and interleave arrays) and [2] (mesa/st/glsl_to_tgsi: Properly 
> resolve life times for simple if/else + use constructs) I sent
> earlier. Considering that both parts target the same optimization 
> step and fix a bug if both are applied, I thought it is better to 
> add this second patch to the series. Changes refer to v1 of [1]: 
> 
> v2: 
>  - rebase patches to latest HEAD
>  - add some code that allows obtaining some statistics about register
>    and instruction usage
>  - Add patch [2] that improves resolving the live range estimation with 
>    simple if/else and use constructs. By adding this patch the series 
>    fixes https://bugs.freedesktop.org/show_bug.cgi?id=105371
> 
>  v1: 
> Patch 1: Split arrays that are only accessed directly:  
> I posted a first version off the the array splitting in patch 1 some 
> time ago. Eric Anholt pointed out that this might be done in 
> opt_array_splitting.cpp, but in another comment Timothy pointed out 
> that this is far from trivial, and he also pointed out that he was 
> proposing similar patches for NIR, but since currently no NIR->TGSI 
> transformation is available, TGSI based drivers can't make use of this. 
> 
> While the reminder off the series could be applied without this patch, I 
> think it makes less sense to do all the optimizations on arrays that could 
> simply be split into individual registers, so I repost the patch with some 
> changes. 
> 
> I tried to be exhaustive with comments and make the variable any type names 
> self-explaining, but since I've been staring at this code for a long time I
> don't think I am capable of seeing any problems any more, so comments are very 
> welcome.
> 
> Best, 
> Gert 
> 
> PS: I have no git write access. 
> 
> 
> [1] https://patchwork.freedesktop.org/series/37991/ 
> [2] https://patchwork.freedesktop.org/series/39471/
> 
> 
> Gert Wollny (13):
>   mesa/st/glsl_to_tgsi: Add method to collect some statistics
>   mesa/st: glsl_to_tgsi: Split arrays who's elements are only accessed
>     directly
>   mesa/st/glsl_to_tgsi: Properly resolve life times simple if/else + use
>     constructs
>   mesa/st/glsl_to_tgsi:rename lifetime to register_live_range
>   mesa/st: Add helper classes for array merging and interleaving
>   mesa/st/glsl_to_tgsi: Add class to track array live range
>   mesa/st/glsl_to_tgsi:Add array merge logic
>   mesa/st/tests: Add tests for array merge helper classes.
>   mesa/st/glsl_to_tgsi: rename access_record to register_merge_record
>     and some more renames
>   mesa/st/glsl_to_tgsi: move evaluation of read mask up in the call
>     hierarchy
>   mesa/st/glsl_to_tgsi: add class for array access tracking
>   mesa/st/glsl_to_tgsi: add array life range evaluation into tracking
>     code
>   mesa/st/glsl_to_tgsi: Expose array live range tracking  and merging
> 
>  src/mesa/Makefile.sources                          |   2 +
>  src/mesa/meson.build                               |   2 +
>  src/mesa/state_tracker/st_glsl_to_tgsi.cpp         | 205 +++++-
>  .../state_tracker/st_glsl_to_tgsi_array_merge.cpp  | 739 +++++++++++++++++++++
>  .../state_tracker/st_glsl_to_tgsi_array_merge.h    | 186 ++++++
>  .../state_tracker/st_glsl_to_tgsi_temprename.cpp   | 304 ++++++---
>  .../state_tracker/st_glsl_to_tgsi_temprename.h     |  45 +-
>  src/mesa/state_tracker/tests/Makefile.am           |  20 +-
>  src/mesa/state_tracker/tests/meson.build           |  14 +
>  src/mesa/state_tracker/tests/st_tests_common.cpp   |  25 +-
>  src/mesa/state_tracker/tests/st_tests_common.h     |  20 +-
>  .../tests/test_glsl_to_tgsi_array_merge.cpp        | 296 +++++++++
>  .../tests/test_glsl_to_tgsi_lifetime.cpp           |  33 +-
>  13 files changed, 1760 insertions(+), 131 deletions(-)
>  create mode 100644 src/mesa/state_tracker/st_glsl_to_tgsi_array_merge.cpp
>  create mode 100644 src/mesa/state_tracker/st_glsl_to_tgsi_array_merge.h
>  create mode 100644 src/mesa/state_tracker/tests/test_glsl_to_tgsi_array_merge.cpp
>