fmha_options.hpp

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#pragma once


#include "cutlass/cutlass.h"

namespace cutlass::fmha::kernel {

template<auto kTag, typename Default, typename... Options>
struct find_option;

template<auto kTag, typename Default>
struct find_option<kTag, Default> {
  using option_value = Default;
};

template<auto kTag, typename Default, typename Option, typename... Options>
struct find_option<kTag, Default, Option, Options...> :
  std::conditional_t<
    Option::tag == kTag,
    Option,
    find_option<kTag, Default, Options...>
  >
{};

template<auto kTag, typename Default, typename... Options>
using find_option_t = typename find_option<kTag, Default, Options...>::option_value;

enum class Tag {
  kIsPersistent,
  kNumMmaWarpGroups,
  kLoadsQSeparately,

  kIsMainloopLocked,
  kIsEpilogueLocked,

  kStagesQ,
  kStagesKV,

  kEpilogueKind,

  kBlocksPerSM,
  kClusterM,

  kAccQK
};

template<auto kTag, class Value>
struct Option {
  static constexpr auto tag = kTag;
  using option_value = Value;
};

}  // namespace cutlass::fmha::kernel