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// Copyright 2017 Steven Stewart-Gallus
//
// See the COPYRIGHT file at the top-level directory of this
// distribution.
//
// 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
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
// implied.  See the License for the specific language governing
// permissions and limitations under the License.
//

use std::sync::atomic;

#[inline(always)]
pub fn pause_times(spins: usize) {
    if 0 == spins {
        return;
    }
    let unroll = 8;
    let start_loops = spins % unroll;
    let outer_loops = spins / unroll;

    for _ in 0..start_loops {
        atomic::spin_loop_hint();
    }

    let mut counter = outer_loops;
    loop {
        match counter.checked_sub(1) {
            None => break,
            Some(newcounter) => {
                counter = newcounter;
            }
        }

        for _ in 0..unroll {
            atomic::spin_loop_hint();
        }
    }
}