Files
composable_kernel/include
Kiefer van Teutem 137f2a9a10 [rocm-libraries] ROCm/rocm-libraries#7407 (commit 0b79e05)
[CK TILE] Initial integration of MFMA / WMMA unification
 framework into CK Tile (#7407) (locked behind flag)

Note: Everything works but this is still a draft MR because I want to do
some more cleanup and maybe do some testing for MX fp6. Also please
don't trigger copilot, I will do this once I feel it is clean enough,
otherwise I'll get a bunch of comments about stuff I already know.

## Motivation
The point of this MR is to finally use our unification MmaPipelines to
replace the existing WarpGemms in CK tile and make sure everything
works. I focused on gfx908 and gfx950 for now, dense and scale
intrinsics, fp16, fp8, and fp4. I managed to get CK tests / examples
working for all of these scenarios, so the basic implementation should
be correct. I expect some more tweaks will be required to get full
support, some of which I already anticipated in the section "New
issues".

## Big switch: USE_NEW_UNIFIED_FRAMEWORK
When USE_NEW_UNIFIED_FRAMEWORK is 1, we replace all WarpGemms with
MmaPipelines from the new unified framework. This means
WarpGemmDispatcher will use the UnificationDispatcher instead of the
regular Dispatcher. Furthermore, named WarpGemms like
WarpGemmMfmaF32F32F32M16N16K4 will also get rerouted to the
UnificationDispatcher. The latter is necessary because some pipelines
bypass the WarpGemmDispatcher in favor of directly using named
WarpGemms.

For now the switch is turned on for easier testing, so don't expect the
CI to pass. When off, this MR should not affect any of the CK tile tests
at all so I *would* expect the CI to pass.

## Simplification of MmaPipelineBase
I found that the structure of MmaPipelineBase was a bit complex and I
was able to reduce it a lot. The only thing an Mma Pipeline does
(currently) is provide a wrapper around amdgcn structs that allows k
iteration and sparse compression. We don't allow M and N composition for
now for simplicity and since this is not expected from WarpGemms in CK
Tile currently.

## Re-interpretation of tile distribution encodings for packed datatypes
Tile distributions for packed types are expected to describe
mathematical elements, not datatype elements! This distinction is why
the gfx950 fp4 CK_tile tests were not working. Updated the
interpretation in amdgcn_mma, tile distribution calculator, and layout
test, along with comments. Tested on all architectures.

## getCMakeCompilerTarget() for configuration time target architecture
This is a workaround because there are a lot of cases in CK Tile where
the host code inspects Device constructions like WarpGemm, and we need
to get the version that *will* be used on the device. This is a big
kludge and we need to figure out a better solution. Also this util will
always pick the *first* cmakelists target arch, so there will be issues
when compiling for multiple target architectures. Ideally, the host code
should not touch the WarpGemms at all, and there would be no issue. This
has been a point of friction in CK for a long time. We can discuss this
with Chris Millette.

## Tests
I was able to verify that the following CK Tile tests and examples work
with the new unified framework:
tile_tutorial_mfma_16x16x16 (gfx9, fp16, uses transpose)
tile_example_gemm_basic (gfx9, fp16)
test_ck_tile_mx_gemm_async (gfx950, microscaling fp8 and fp4)

Within the tile tutorial I was also able to use
WarpGemmMfmaF16F16F32M16N16K32TransposedCDistribution instead of
WarpGemmMfmaF16F16F32M16N16K16TransposedCDistribution to verify that
basic K iteration also works.

A little while ago I also verified that the performance did not change
in a measurable way, and the compile did not change *much* but did see
some swings up to 20% each way (faster or slower). We will need some
broader and more accurate tests for this going forward.

## Moving forward
To confidently be able to replace the existing Dispatcher and WarpGemm
framework with our own, we need to make sure that all existing tests and
examples work on all platforms. Furthermore, we should pay attention to
performance and compile time of all these tests. Performance should
definitely not change, as all we're doing is refactoring the support
structure around the intrinsics, which should melt away during
compilation.

## New issues
(I will make new issues with descriptions for these but here is a short
list (incomplete):

Test RDNA CK Tile pipelines
Test Sparse Ck Tile pipeline (does not exist but we can make one)
Remove MmaOp flags from unification framework and update it to work with
new WarpGemmParamsParser instead.
Add Swizzle support and test in CK Tile pipelines.
Test Scale + transpose Ck Tile pipelines.
Coherent strategy for attrnumaccess for dense, scale, default, packed,
wmma, gfx1250, etc in CK tile. It's messy now.
Dispatcher should not be determining scale-ness of intrinsics based on
MNK sizes.
Try adding back the MN composition in MmaPipelines
Why is test_amdgcn_wavewise_mma only compiled for CDNA?
Investigate NOP and AGPR flags
Maybe get rid of WmmaTag in dispatcher.
Find a coherent strategy for dealing with host vs device compile passes,
and the host sneaking a peak at WarpGemm internals. Related to
getCMakeCompilerTarget().

## TODO before merge
Some changes exist just for ease of testing, and will be reverted before
merging:
- gemm_basic.cpp has a lot of datatypes disabled because otherwise
compile time is huge for testing
- USE_NEW_UNIFIED_FRAMEWORK is set to 1 for easier testing
2026-06-24 13:35:25 +00:00
..