Files
composable_kernel/experimental
Johannes Graner 01cca38c8e [rocm-libraries] ROCm/rocm-libraries#8220 (commit 4c04a3a)
[CK Tile] WAVELET pipeline for backward-data grouped
 convolution (#8220)

## Motivation

On the RetinaNet shapes (gfx950, fp16) CK Tile backward-data conv was
~18% behind classic
CK, with the gap concentrated in the K=2376 3x3 detection-head family
where bwd_data spends
most of its time. The WAVELET GEMM pipeline already gives uplift for
forward and
backward-weight conv; this ports it to backward-data and consolidates
the now-shared
machinery across all three directions.

## Technical Details

- Backward-data wavelet support in the tile kernel: launch extra load
waves when the
pipeline exposes `LaunchBlockSize`, and split the epilogue into math
waves (run the
  CShuffle epilogue) and load waves (`RunBarrierStub`).
- Register 7 WAVELET instances (fp16 and bf16), tuned for
backward-data's tall-skinny GEMM
rather than the forward tile shapes: a big-M `256/128/64` workhorse, a
`VecA=4` variant for
the `K % 8 != 0` shapes, and a `NumGroupsToMerge=32` variant for grouped
(depthwise-style)
  shapes.
- Implement the native backward-data instance parser in
`generate_instances.py`.
- Deduplicate the wavelet machinery shared by forward, backward-data,
and backward-weight:
`GroupedConvLaunchBlockSize`, `is_wavelet_pipeline`, and
`RunWaveletAwareEpilogue` in
`grouped_convolution_utils.hpp`; the three native instance parsers
collapse to one
  parameterized parser. The three kernels now call the shared helpers.

## Test Plan

- Rebuild the full profiler instance pools for all three directions
(fp16/bf16/fp32,
nhwgc/ndhwgc) to exercise the shared helpers across every instantiation.
- Tile GTests on gfx950: `test_grouped_convnd_fwd_tile`,
`test_grouped_convnd_bwd_data_tile`,
  `test_grouped_convnd_bwd_weight_tile`.
- Per-shape sweep of the 35 RetinaNet backward-data shapes vs classic CK
and the
non-wavelet tile pool (`profile_wavelet_bwd_data.py`); correctness
spot-checked with
GPU-reference verification on the new big-M and NumGroupsToMerge
instances.

## Test Result

- GTests pass: forward 9/9, backward-data 6/6, backward-weight 6/6.
- Backward-data perf (3x3 g=1 region, geomean classic/tile): 0.88 ->
1.11, i.e. the tile
path goes from ~12% slower than classic to ~8% faster. The largest
single backward-data
shape (256x100x100->2376) moves from 11% slower than classic to 12.5%
faster.
- The dedup refactor preserves behavior (net -174 lines across the
kernels/generator),
  confirmed by the full rebuild and the GTests above.

## Submission Checklist

- [ ] Look over the contributing guidelines at
https://github.com/ROCm/ROCm/blob/develop/CONTRIBUTING.md#pull-requests.
2026-06-13 00:10:50 +00:00
..