topk_softmax (#1592)

* topk_softmax

* remove some file

* fix atomix linear_offset

* address various comment, and change sfc get_index api to static(tuple)

example/ck_tile/09_topk_softmax/README.md

@@ -0,0 +1,28 @@
+# topk-softmax
+
+This folder contains example for topk-softmax kernel using ck_tile tile-programming implementation. This kernel is often used in Moe model, before launching the fused-moe-gemm block. The input is a `token*expert` 2d matrix. The op will do a softmax per row(`expert`), then find the `topk` value for each row. Output is a `token*topk`  weight(usually fp32) and index(int32) 2d tensor.
+
+## 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_topk_softmax -j
+```
+This will result in an executable `build/bin/tile_example_topk_softmax`
+
+## example
+```
+args:
+          -v    weather do CPU validation or not (default:1)
+       -pr_i    input data type. fp16/fp32 (representing 8/16/32 bit data) (default:fp16)
+       -pr_w    output weight data type(currently only fp32 supported now) (default:fp32)
+          -t    number of input tokens (default:32)
+          -e    number of experts (default:8)
+          -k    topk (default:2)
+       -st_i    row stride of input, -1 means same as experts (default:-1)
+       -st_o    row stride of output/indices, -1 means same as topk (default:-1)
+       -seed    seed to be used, -1 means random every time (default:-1)
+      -kname    when set to 1 it will print kernel name (default:0)
+
+```