9 Commits

Author SHA1 Message Date
Jon Chesterfield
d77ae7f251 [amdgpu] Reimplement LDS lowering
Renames the current lowering scheme to "module" and introduces two new
ones, "kernel" and "table", plus a "hybrid" that chooses between those three
on a per-variable basis.

Unit tests are set up to pass with the default lowering of "module" or "hybrid"
with this patch defaulting to "module", which will be a less dramatic codegen
change relative to the current. This reflects the sparsity of test coverage for
the table lowering method. Hybrid is better than module in every respect and
will be default in a subsequent patch.

Reviewed By: arsenm

Differential Revision: https://reviews.llvm.org/D139433
2022-12-07 22:02:54 +00:00
Nico Weber
a862d09a92 Revert "[amdgpu] Reimplement LDS lowering"
This reverts commit 982017240d7f25a8a6969b8b73dc51f9ac5b93ed.
Breaks check-llvm, see https://reviews.llvm.org/D139433#3974862
2022-12-06 12:01:36 -05:00
Jon Chesterfield
982017240d [amdgpu] Reimplement LDS lowering
Renames the current lowering scheme to "module" and introduces two new
ones, "kernel" and "table", plus a "hybrid" that chooses between those three
on a per-variable basis.

Unit tests are set up to pass with the default lowering of "module" or "hybrid"
with this patch defaulting to "module", which will be a less dramatic codegen
change relative to the current. This reflects the sparsity of test coverage for
the table lowering method. Hybrid is better than module in every respect and
will be default in a subsequent patch.

Reviewed By: arsenm

Differential Revision: https://reviews.llvm.org/D139433
2022-12-06 16:28:15 +00:00
Jon Chesterfield
23f6c8d635 [amdgpu] Always, instead of mostly, remove unused LDS symbols
Currently LDS variables are removed by the lower module pass
if they have a use which is caught by the replace with struct control flow.
This makes tests brittle to changes to that control flow which induces
noise when trying to improve lowering. Some tests already check that
variables are removed, while others checked that they are not removed.

LDS variables are not (currently) externally accessible, and if that
changes the machinery which makes them externally accessible will look
like a use. This change therefore breaks no applications.

Reviewed By: rampitec

Differential Revision: https://reviews.llvm.org/D133028
2022-09-07 18:28:16 +01:00
Jon Chesterfield
24b28db8cc [amdgpu] Increase alignment of all LDS variables
Currently the superalign option only increases the alignment of
variables that are moved into the module.lds block. Change that to all LDS
variables. Also only increase the alignment once, instead of once per function.

Reviewed By: rampitec

Differential Revision: https://reviews.llvm.org/D115488
2021-12-12 19:30:32 +00:00
Stanislav Mekhanoshin
d274d64ef4 [AMDGPU] Check for pointer operand while refining LDS align
Also skips the propagation if alignment is 1.

Differential Revision: https://reviews.llvm.org/D104796
2021-06-23 12:27:55 -07:00
Stanislav Mekhanoshin
2b43209ee3 [AMDGPU] Propagate LDS align into to instructions
Differential Revision: https://reviews.llvm.org/D104316
2021-06-23 00:57:16 -07:00
Stanislav Mekhanoshin
a11880468e [AMDGPU] Fix lds superalign test. NFC. 2021-06-15 11:02:34 -07:00
hsmahesha
713ca2f360 [AMDGPU] Introduce command line switch to control super aligning of LDS.
Reviewed By: rampitec

Differential Revision: https://reviews.llvm.org/D103817
2021-06-08 03:58:13 +05:30