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// Copyright 2018 The gVisor Authors.
//
// 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.
package bits
// Non-atomic bit operations on a template type T.
// T is a required type parameter that must be an integral type.
type T uint64
// IsOn returns true if *all* bits set in 'bits' are set in 'mask'.
func IsOn(mask, bits T) bool {
return mask&bits == bits
}
// IsAnyOn returns true if *any* bit set in 'bits' is set in 'mask'.
func IsAnyOn(mask, bits T) bool {
return mask&bits != 0
}
// Mask returns a T with all of the given bits set.
func Mask(is ...int) T {
ret := T(0)
for _, i := range is {
ret |= MaskOf(i)
}
return ret
}
// MaskOf is like Mask, but sets only a single bit (more efficiently).
func MaskOf(i int) T {
return T(1) << T(i)
}
// IsPowerOfTwo returns true if v is power of 2.
func IsPowerOfTwo(v T) bool {
if v == 0 {
return false
}
return v&(v-1) == 0
}
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