github.com/songzhibin97/gkit@v1.2.13/cache/mbuffer/utils.go (about)

     1  // Copyright 2021 ByteDance Inc.
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //     http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  
    15  package mbuffer
    16  
    17  import "math/bits"
    18  
    19  func bsr(x int) int {
    20  	return bits.Len(uint(x)) - 1
    21  }
    22  
    23  func isPowerOfTwo(x int) bool {
    24  	return (x & (-x)) == x
    25  }