barrier.hpp

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 * Copyright (c) 2022-2023 Intel Corporation
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
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 * distributed under the License is distributed on an "AS IS" BASIS,
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/// @file
/// C++ API

#pragma once

#include <common/core/common.hpp>

namespace gpu::xetla {

/// @addtogroup xetla_core_barrier
/// @{

/// sw_barrier, insert software scheduling barrier, for better code control
///

void sw_barrier() {
#if __INTEL_LLVM_COMPILER >= 20250000
#else
  __ESIMD_NS::fence<__ESIMD_NS::fence_mask::sw_barrier>();
#endif
}

/// @brief Initialize the number of named barrier index for a kernel.
/// Available only on PVC. Only need to initialize once at the beginning.
///
/// @tparam NbarCount  - number of named barriers.
template <uint8_t NbarCount>
__XETLA_API void xetla_nbarrier_init() {
  if constexpr (NbarCount != 0) {
#if __INTEL_LLVM_COMPILER >= 20250000
    __ESIMD_NS::named_barrier_init<NbarCount>();
#else
    __ESIMD_ENS::named_barrier_init<NbarCount>();
#endif
  }
}

/// @brief Perform signal operation for the given named barrier id.
/// Available only on PVC.
///
/// @param barrier_id  [in] is the named barrier id.
///
/// @param producer_consumer_mode  [in] is 2-bit flag to indicate if it's
/// producer-consumer mode(0x0) or producer mode (0x1) or consumer mode (0x2).
/// User must ensure the input value is set correctly and higher order bits are
/// cleared.
///
/// @param num_producers  [in] is the number of producers.
///
/// @param num_consumers  [in] is the number of consumers.
__XETLA_API void named_barrier_signal(
    uint8_t barrier_id,
    uint8_t producer_consumer_mode,
    uint32_t num_producers,
    uint32_t num_consumers) {
#if __INTEL_LLVM_COMPILER >= 20250000
  __ESIMD_NS::named_barrier_signal(
      barrier_id, producer_consumer_mode, num_producers, num_consumers);
#else
  __ESIMD_ENS::named_barrier_signal(
      barrier_id, producer_consumer_mode, num_producers, num_consumers);
#endif
}

/// @brief Wait on a named barrier.
/// Available only on PVC
///
/// @param barrier_id  [in] is the named barrier id.
/// It’s value cannot exceed the total count of initialized named barriers.
__XETLA_API void named_barrier_wait(uint8_t barrier_id) {
#if __INTEL_LLVM_COMPILER >= 20250000
  __ESIMD_NS::named_barrier_wait(barrier_id);
#else
  __ESIMD_ENS::named_barrier_wait(barrier_id);
#endif
}

/// @} xetla_core_barrier

} // namespace gpu::xetla