Files
composable_kernel/example/ck_tile/03_gemm
JP-Fernando e7798e9560 [rocm-libraries] ROCm/rocm-libraries#7112 (commit a6e5eac)
Add asynchronous XOR shuffle support to the Async GEMM pipeline and the MX GEMM pipeline (#7112)

## Motivation

The goal of this work is to apply XOR shuffle (swizzle) to the current
`comp_async` GEMM pipeline and the `gemm_mx` pipeline.
XOR swizzling has been helpful to avoid LDS bank conflicts, as data are
redistributed across LDS banks, such that simultaneous threads accessing
different rows land on different LDS banks.

## Technical Details

A similar approach to the work in the existing eight-waves pipeline was
followed.
Currently, XOR swizzle support is available for FP8 and BF8 types.
FP4 support is also available for MX GEMM.
Should the types not match, or should the async vector width be of an
unsupported size, then the pipeline falls through to the previously
existing ('unswizzled') path.

## Test Plan

Execute `test_ck_tile_gemm_pipeline_comp_async` for the Async GEMM
pipeline.
Execute `test_ck_tile_mx_gemm_fp8` and `test_ck_tile_mx_gemm_fp4` for
the MX GEMM pipeline.

## Test Result

The tests passed successfully in the `Alola` cluster with MI350
hardware.

## Submission Checklist

- [X] Look over the contributing guidelines at
https://github.com/ROCm/ROCm/blob/develop/CONTRIBUTING.md#pull-requests.

---------

Co-authored-by: Fernando Jiménez <fernando.jimenez@streamhpc.com>
Co-authored-by: Illia Silin <98187287+illsilin@users.noreply.github.com>
2026-05-21 09:36:41 +02:00
..

GEMM with CK Tile

This example demonstrates matrix multiplication (GEMM) using the CK Tile programming model, focusing on tile-based parallelism and modular kernel design.


Algorithm and Math

GEMM computes:


C = A \times B

where A is [M, K], B is [N, K], and C is [M, N].

  • BlockTile GEMM: Each Block Tile computes a tile of C by loading tiles of A and B, performing blockwise matrix multiply-accumulation, and writing results back with the epilogue.

Tile Programming Model

  • Configuration: The Configuration of how the kernel going to be initialized with Block Tile Dimension, Warps Layout, Warp Tile Dimension, and other improvements.
  • Block Tile: Each block tile allocates in the compute unit of AMD GPU grabbing the .
  • Pipeline: Modular design allows swapping different memory/computation pipelines (e.g., basic, memory-bound, compute).
  • Block GEMM: Block Level implementation on how to coordinate the warps iteration and memory layout in block tile.
  • Warp GEMM: Each Warp's GEMM Calculation
  • Epilogue: Transferring the Accumulated result from register to global memory.

Features

  • Flexible Layouts: Supports row/column-major and custom strides for A, B, C.
  • Split K: Split the Block Tile also on K Dimension and add it back after the matrix multiply-accumulation. Have a higher performance when M and N is small and K is large.
  • Preshuffled GEMM: In inference task, shuffle the GEMM of B (weight) matrix in the warp layout and bypass the shared memory to do the GEMM calculation. Best performance solution for GEMM.
  • Precision: Supports fp16, bf16, fp8, bf8, int4 (for B Matrix).
  • Validation: CPU/GPU validation and error tolerance options.

Build & Run

mkdir build && cd build
# you can replace <arch> with the appropriate architecture (for example gfx90a or gfx942) or leave it blank
../script/cmake-ck-dev.sh  ../ <arch>
# The basic pipeline method on the gemm calculation
make tile_example_gemm_basic -j`nproc`
# The memory bound pipeline on the gemm calculation
make tile_example_gemm_universal -j`nproc`
# The weight preshuffle pipeline on the gemm calculation
make tile_example_gemm_weight_preshuffle -j`nproc`
# gfx125 only: weight preshuffle TDM pipeline with data cache prefetch controls
make tile_example_gemm_weight_preshuffle_tdm_data_cache_prefetch -j`nproc`

This will result in an executable build/bin/tile_example_gemm_basic & build/bin/tile_example_gemm_universal

example

args:
          -m    m dimension (default:1024)
          -n    n dimension (default:2048)
          -k    k dimension (default:64)
   -a_layout    Tensor A data layout (default: R)
   -b_layout    Tensor B data layout (default: C)
   -c_layout    Tensor C data layout (default: R)
   -stride_a    Tensor A stride (default:0)
   -stride_b    Tensor B stride (default:0)
   -stride_c    Tensor C stride (default:0)
          -v    0. No validation, 1. Validation on CPU, 2. Validation on GPU (default:2)
       -prec    data type. fp16/bf16/fp8/bf8 (default:fp16)
     -warmup    number of iterations before benchmark the kernel (default:50)
     -repeat    number of iterations to benchmark the kernel (default:100)
      -timer    gpu:gpu timer, cpu:cpu timer (default:gpu)
          -split_k    splitK value (default:1)
       -init    0:random, 1:linear, 2:constant(1) (default:0)
 -persistent    0:non-persistent, 1:persistent (default:0)
       -json    0: No Json, 1: Dump Results in Json format (default:0)
   -jsonfile    json file name to dump results (default:gemm.json)

Source Structure

  • Executables: gemm_basic.cpp, universal_gemm.cpp (different kinds of GEMM implementation)
  • Utils: gemm_utils.hpp (helper functions)
  • Build: CMakeLists.txt, run_gemm_example.inc
  • Scripts: script/ (build and run helpers)

For distribution, see include/ck_tile/tile_program/tile_distribution/.


Back to CK Tile Examples