//===-- Utils/ExponentialBackoff.h - Heuristic helper class ------*- C++ -*===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// Implement exponential backoff counting.
// Linearly increments until given maximum, exponentially decrements based on
// given backoff factor.
//
//===----------------------------------------------------------------------===//
#ifndef OMPTARGET_UTILS_EXPONENTIAL_BACKOFF_H
#define OMPTARGET_UTILS_EXPONENTIAL_BACKOFF_H
#include <cassert>
#include <cmath>
#include <cstdint>
namespace utils {
class ExponentialBackoff {
int64_t Count = 0;
const int64_t MaxCount = 0;
const int64_t CountThreshold = 0;
const double BackoffFactor = 0;
public:
ExponentialBackoff(int64_t MaxCount, int64_t CountThreshold,
double BackoffFactor)
: MaxCount(MaxCount), CountThreshold(CountThreshold),
BackoffFactor(BackoffFactor) {
assert(MaxCount >= 0 &&
"ExponentialBackoff: maximum count value should be non-negative");
assert(CountThreshold >= 0 &&
"ExponentialBackoff: count threshold value should be non-negative");
assert(BackoffFactor >= 0 && BackoffFactor < 1 &&
"ExponentialBackoff: backoff factor should be in [0, 1) interval");
}
void increment() { Count = std::min(Count + 1, MaxCount); }
void decrement() { Count *= BackoffFactor; }
bool isAboveThreshold() const { return Count > CountThreshold; }
};
} // namespace utils
#endif // OMPTARGET_UTILS_EXPONENTIAL_BACKOFF_H