8 Commits

Author SHA1 Message Date
Fangrui Song
9e9907f1cf
[AMDGPU,test] Change llc -march= to -mtriple= (#75982)
Similar to 806761a7629df268c8aed49657aeccffa6bca449.

For IR files without a target triple, -mtriple= specifies the full
target triple while -march= merely sets the architecture part of the
default target triple, leaving a target triple which may not make sense,
e.g. amdgpu-apple-darwin.

Therefore, -march= is error-prone and not recommended for tests without
a target triple. The issue has been benign as we recognize
$unknown-apple-darwin as ELF instead of rejecting it outrightly.

This patch changes AMDGPU tests to not rely on the default
OS/environment components. Tests that need fixes are not changed:

```
  LLVM :: CodeGen/AMDGPU/fabs.f64.ll
  LLVM :: CodeGen/AMDGPU/fabs.ll
  LLVM :: CodeGen/AMDGPU/floor.ll
  LLVM :: CodeGen/AMDGPU/fneg-fabs.f64.ll
  LLVM :: CodeGen/AMDGPU/fneg-fabs.ll
  LLVM :: CodeGen/AMDGPU/r600-infinite-loop-bug-while-reorganizing-vector.ll
  LLVM :: CodeGen/AMDGPU/schedule-if-2.ll
```
2024-01-16 21:54:58 -08:00
Alex Richardson
e39f6c1844 [opt] Infer DataLayout from triple if not specified
There are many tests that specify a target triple/CPU flags but no
DataLayout which can lead to IR being generated that has unusual
behaviour. This commit attempts to use the default DataLayout based
on the relevant flags if there is no explicit override on the command
line or in the IR file.

One thing that is not currently possible to differentiate from a missing
datalayout `target datalayout = ""` in the IR file since the current
APIs don't allow detecting this case. If it is considered useful to
support this case (instead of passing "-data-layout=" on the command
line), I can change IR parsers to track whether they have seen such a
directive and change the callback type.

Differential Revision: https://reviews.llvm.org/D141060
2023-10-26 12:07:37 -07:00
Alex Richardson
83c4227ab7 Auto-generate test checks for tests affected by D141060
These files had manual CHECK lines which make the diff from D141060
very difficult to review.
2023-10-04 10:51:35 -07:00
Jon Chesterfield
d3dda422bf [amdgpu][nfc] Replace ad hoc LDS frame recalculation with absolute_symbol MD
Post ISel, LDS variables are absolute values. Representing them as
such is simpler than the frame recalculation currently used to build assembler
tables from their addresses.

This is a precursor to lowering dynamic/external LDS accesses from non-kernel
functions.

Reviewed By: arsenm

Differential Revision: https://reviews.llvm.org/D144221
2023-03-12 13:47:48 +00:00
Matt Arsenault
5a4a8eb2b6 AMDGPU: Convert some tests to opaque pointers 2023-01-25 14:33:20 -04:00
Nikita Popov
9ed2f14c87 [AsmParser] Remove typed pointer auto-detection
IR is now always parsed in opaque pointer mode, unless
-opaque-pointers=0 is explicitly given. There is no automatic
detection of typed pointers anymore.

The -opaque-pointers=0 option is added to any remaining IR tests
that haven't been migrated yet.

Differential Revision: https://reviews.llvm.org/D141912
2023-01-18 09:58:32 +01:00
Jay Foad
359a792f9b [AMDGPU] SILoadStoreOptimizer: avoid unbounded register pressure increases
Previously when combining two loads this pass would sink the
first one down to the second one, putting the combined load
where the second one was. It would also sink any intervening
instructions which depended on the first load down to just
after the combined load.

For example, if we started with this sequence of
instructions (code flowing from left to right):

  X A B C D E F Y

After combining loads X and Y into XY we might end up with:

  A B C D E F XY

But if B D and F depended on X, we would get:

  A C E XY B D F

Now if the original code had some short disjoint live ranges
from A to B, C to D and E to F, in the transformed code
these live ranges will be long and overlapping. In this way
a single merge of two loads could cause an unbounded
increase in register pressure.

To fix this, change the way the way that loads are moved in
order to merge them so that:
- The second load is moved up to the first one. (But when
  merging stores, we still move the first store down to the
  second one.)
- Intervening instructions are never moved.
- Instead, if we find an intervening instruction that would
  need to be moved, give up on the merge. But this case
  should now be pretty rare because normal stores have no
  outputs, and normal loads only have address register
  inputs, but these will be identical for any pair of loads
  that we try to merge.

As well as fixing the unbounded register pressure increase
problem, moving loads up and stores down seems like it
should usually be a win for memory latency reasons.

Differential Revision: https://reviews.llvm.org/D119006
2022-02-21 10:51:14 +00:00
Stanislav Mekhanoshin
8d7d89b081 [AMDGPU] Add alias.scope metadata to lowered LDS struct
Alias analysis is unable to disambiguate accesses to the structure
fields without it unlike distinct variables. As a result we cannot
combine ds_read and ds_write operations in a case of any store in
between which always considered clobbering.

Differential Revision: https://reviews.llvm.org/D108315
2021-08-19 11:40:30 -07:00