mirror of https://github.com/ROCm/composable_kernel.git synced 2026-05-05 06:01:23 +00:00

Files

Po Yen Chen 14f7834a23 [rocm-libraries] ROCm/rocm-libraries#6342 (commit 31bcb51)

[CK] Skip fp16 dropout d256 batch tests for compiler VGPR
 aliasing bug (#6342)

## Summary

- Skip fp16 FMHA forward dropout tests that use the d256 tile in batch
mode, gated on compiler version
- The AMDGPU compiler miscompiles these kernels due to VGPR aliasing of
Philox RNG parameters under high register pressure (383 VGPRs)
- bf16 dropout tests are unaffected and cover the same code paths

## Root Cause

The compiler aliases `ph_seed` and `ph_head_offset` (Philox RNG state
stored in VGPRs) with other live data during the softmax main loop. This
causes corrupted `buffer_store_byte` writes for dropout randval on wave
lanes 32-63, producing NaN in output and LSE tensors.

**Conditions:** fp16 + d256 tile + dropout + batch mode + `qr` pipeline
+ gfx90a

## Changes

- `include/ck_tile/core/config.hpp`: Add
`CK_TILE_WORKAROUND_ROCM_7_12_FP16_DROPOUT_MISCOMPILE` macro
- `test/ck_tile/fmha/test_fmha_fwd.cpp`: Version-gated `GTEST_SKIP` in
`TEST_P(Dropout, ...)`

## Test plan

- [x] ROCm 7.1.1 (clang 20): 168/168 fp16 dropout tests PASS (no skip
active)
- [x] ROCm 7.12 (clang 22): 132 PASS, 36 SKIPPED, 0 FAILED
- [x] bf16 dropout tests: 168/168 PASS (unaffected by this change)

2026-04-14 14:08:44 +00:00

algorithm

[rocm-libraries] ROCm/rocm-libraries#5334 (commit bb5a3c8)

2026-03-20 15:47:22 +00:00

arch

[rocm-libraries] ROCm/rocm-libraries#6302 (commit 8d419e8)

2026-04-10 15:18:02 +00:00

container

[rocm-libraries] ROCm/rocm-libraries#6302 (commit 8d419e8)

2026-04-10 15:18:02 +00:00

numeric

[rocm-libraries] ROCm/rocm-libraries#6302 (commit 8d419e8)

2026-04-10 15:18:02 +00:00

tensor

[rocm-libraries] ROCm/rocm-libraries#6302 (commit 8d419e8)

2026-04-10 15:18:02 +00:00

utility

[rocm-libraries] ROCm/rocm-libraries#5938 (commit 73f3650)

2026-04-02 21:25:56 +00:00

config.hpp

[rocm-libraries] ROCm/rocm-libraries#6342 (commit 31bcb51)

2026-04-14 14:08:44 +00:00

README.md

introducing ck_tile! (#1216 )

2024-04-15 19:27:12 -05:00

README.md

ck_tile/core

ck_tile/core contains every basic functions and structures to create a GPU kernel using ck_tile. User should only include ck_tile/core.hpp this single header to use all the functionality. Everything is under ck_tile namespace. The coding style under this folder should be similar to std (snake_case for structure/function, Camel for template types...)

algorithm/
    coordinate transform and some other reusable algorithm
arch/
    contains some basic device building block like mma, buffer addressing, etc...
container/
    contains basic container data structure, array/sequence/tuple/...
numeric/
    data type, and data type related math
tensor/
    tensor descriptors and tile level API
utility/
    other utility function for both host/device