xref: /external/chromium_org/v8/src/circular-queue-inl.h

// Copyright 2011 the V8 project authors. All rights reserved.
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#ifndef V8_CIRCULAR_QUEUE_INL_H_
#define V8_CIRCULAR_QUEUE_INL_H_

#include "circular-queue.h"

namespace v8 {
namespace internal {


void* SamplingCircularQueue::Enqueue() {
  if (producer_pos_->enqueue_pos == producer_pos_->next_chunk_pos) {
    if (producer_pos_->enqueue_pos == buffer_ + buffer_size_) {
      producer_pos_->next_chunk_pos = buffer_;
      producer_pos_->enqueue_pos = buffer_;
    }
    Acquire_Store(producer_pos_->next_chunk_pos, kEnqueueStarted);
    // Skip marker.
    producer_pos_->enqueue_pos += 1;
    producer_pos_->next_chunk_pos += chunk_size_;
  }
  void* result = producer_pos_->enqueue_pos;
  producer_pos_->enqueue_pos += record_size_;
  return result;
}


void SamplingCircularQueue::WrapPositionIfNeeded(
    SamplingCircularQueue::Cell** pos) {
  if (*pos == buffer_ + buffer_size_) *pos = buffer_;
}


} }  // namespace v8::internal

#endif  // V8_CIRCULAR_QUEUE_INL_H_