This folder contains example for permute kernel, which is similiar to torch.permute (combined with torch.contiguous). Currently we implement a generic permute kernel that support up to rank 8 arbitrary permutation with a single kernel instance. Performance is not the first consideration, we prefer a simple and general kernel implementation using ck_tile in this example.

args:
          -v    weather do CPU validation or not (default:1)
       -prec    data type. fp16/bf16/fp32 (default:fp16)
      -shape    the shape of the input tensor (default:2,3,4)
       -perm    permute perm (default:2,1,0)

build

# in the root of ck_tile
mkdir build && cd build
../script/cmake-ck-dev.sh  ../ <arch>  # you can replace this <arch> to gfx90a, gfx942...
make tile_example_permute -j

This will result in an executable build/bin/tile_example_permute

some examples

# torch
x=torch.randn(2,3,4,6)
y=x.permute(0,3,2,1).contiguous()

# ck_tile
./build/bin/tile_example_permute -shape=2,3,4,6 -perm=0,3,2,1

or you can try the smoke_test

# in the root of ck_tile, after you build this example
sh example/ck_tile/06_permute/script/smoke_test.sh

alternative implementation

we have an alternative implementation under alternative_impl/ folder, that can swizzle the tensor to be more friendly for data loading for matrix core layout. This can be enabled when dealing with a rank-7 tensor, with a fixed pattern of either 0,1,4,2,5,3,6 or 0,1,2,4,5,3,6. There are other shape limitation of this implementation, check the source code of permute.cpp for detail.

# example
./build/bin/tile_example_permute -shape=3,6,4,32,16,2,8 -perm=0,1,4,2,5,3,6 # b_n0_k0_n1_k1_n2_k2
./build/bin/tile_example_permute -shape=3,8,4,16,16,4,8 -perm=0,1,2,4,5,3,6 # b_n0_n1_k0_k1_n2_k2