This folder contains example for permute kernel, which is similiar to [torch.permute](https://pytorch.org/docs/stable/generated/torch.permute.html)(combined with [torch.contiguous](https://pytorch.org/docs/stable/generated/torch.Tensor.contiguous.html)). 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
sh ../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`
# 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.
