text: //===--------- statequeue.h - NVPTX OpenMP GPU State Queue ------- CUDA -*-===//
  //
  //                     The LLVM Compiler Infrastructure
  //
  // This file is dual licensed under the MIT and the University of Illinois Open
  // Source Licenses. See LICENSE.txt for details.
  //
  //===----------------------------------------------------------------------===//
  //
  // This file contains a queue to hand out OpenMP state objects to teams of
  // one or more kernels.
  //
  // Reference:
  // Thomas R.W. Scogland and Wu-chun Feng. 2015.
  // Design and Evaluation of Scalable Concurrent Queues for Many-Core
  // Architectures. International Conference on Performance Engineering.
  //
  //===----------------------------------------------------------------------===//
  
  #ifndef __STATE_QUEUE_H
  #define __STATE_QUEUE_H
  
  #include <stdint.h>
  
  #include "option.h" // choices we have
  
  template<typename ElementType, uint32_t SIZE>
  class omptarget_nvptx_Queue {
  private:
    ElementType elements[SIZE];
    volatile ElementType *elementQueue[SIZE];
    volatile uint32_t head;
    volatile uint32_t ids[SIZE];
    volatile uint32_t tail;
  
    static const uint32_t MAX_ID = (1u << 31) / SIZE / 2;
    INLINE uint32_t ENQUEUE_TICKET();
    INLINE uint32_t DEQUEUE_TICKET();
    INLINE uint32_t ID(uint32_t ticket);
    INLINE bool IsServing(uint32_t slot, uint32_t id);
    INLINE void PushElement(uint32_t slot, ElementType *element);
    INLINE ElementType *PopElement(uint32_t slot);
    INLINE void DoneServing(uint32_t slot, uint32_t id);
  
  public:
    INLINE omptarget_nvptx_Queue() {};
    INLINE void Enqueue(ElementType *element);
    INLINE ElementType *Dequeue();
  };
  
  #include "state-queuei.h"
  
  #endif
  