topk_softmax (#1592)

* topk_softmax

* remove some file

* fix atomix linear_offset

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

include/ck_tile/ops/topk_softmax/pipeline/topk_softmax_warp_per_row_problem.hpp

+// SPDX-License-Identifier: MIT
+// Copyright (c) 2018-2024, Advanced Micro Devices, Inc. All rights reserved.
+
+#pragma once
+
+#include "ck_tile/core.hpp"
+#include <string>
+#include <type_traits>
+
+namespace ck_tile {
+
+template <typename InputType_,
+          typename WeightType_,
+          typename IndexType_,
+          index_t Experts_,
+          index_t IssuesPerCol_  = 2, // issue along col, to make sure block_reduce() OK
+          index_t BytesPerIssue_ = sizeof(InputType_),
+          index_t LaunchType_    = 0, // 0-streaming, >0, persistent #occupancy
+          index_t BlockSize_     = 256>
+struct TopkSoftmaxWarpPerRowProblem
+{
+    // TODO: this kernel only support warp per row
+    using InputType  = remove_cvref_t<InputType_>;
+    using WeightType = remove_cvref_t<WeightType_>;
+    using IndexType  = remove_cvref_t<IndexType_>;
+
+    static constexpr index_t LaunchType    = LaunchType_;
+    static constexpr index_t Experts       = Experts_;
+    static constexpr index_t BytesPerIssue = BytesPerIssue_;
+    static constexpr index_t IssuesPerCol  = IssuesPerCol_;
+    static constexpr index_t BlockSize     = BlockSize_;
+    static constexpr index_t WarpSize      = get_warp_size();
+
+    static_assert(BytesPerIssue % sizeof(InputType) == 0);
+    static constexpr index_t VectorSize = BytesPerIssue / sizeof(InputType);
+    static_assert(Experts % VectorSize == 0);
+    static constexpr index_t LanesPerRow = min(Experts / VectorSize, WarpSize);
+    static_assert(WarpSize % LanesPerRow == 0);
+    static constexpr index_t RowsPerWarpPerColIssue = WarpSize / LanesPerRow;
+    static constexpr index_t RowsPerWarp            = IssuesPerCol * RowsPerWarpPerColIssue;
+    static constexpr index_t IssuesPerRow           = Experts / (LanesPerRow * VectorSize);
+
+    static constexpr index_t WarpsPerBlock = BlockSize / WarpSize;
+    static constexpr index_t RowsPerBlock  = RowsPerWarp * WarpsPerBlock;
+};
+} // namespace ck_tile