gotosocial/vendor/github.com/golang/geo/s2/bits_go19.go
Tobi Smethurst 98263a7de6
Grand test fixup (#138)
* start fixing up tests

* fix up tests + automate with drone

* fiddle with linting

* messing about with drone.yml

* some more fiddling

* hmmm

* add cache

* add vendor directory

* verbose

* ci updates

* update some little things

* update sig
2021-08-12 21:03:24 +02:00

40 lines
1.2 KiB
Go

// Copyright 2018 Google Inc. All rights reserved.
//
// 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.
// +build go1.9
package s2
// This file is for the bit manipulation code post-Go 1.9.
import "math/bits"
// findMSBSetNonZero64 returns the index (between 0 and 63) of the most
// significant set bit. Passing zero to this function return zero.
func findMSBSetNonZero64(x uint64) int {
if x == 0 {
return 0
}
return 63 - bits.LeadingZeros64(x)
}
// findLSBSetNonZero64 returns the index (between 0 and 63) of the least
// significant set bit. Passing zero to this function return zero.
func findLSBSetNonZero64(x uint64) int {
if x == 0 {
return 0
}
return bits.TrailingZeros64(x)
}