//go:build go1.9 // +build go1.9 // "go1.9", from Go version 1.9 onward // See https://golang.org/pkg/go/build/#hdr-Build_Constraints package roaring import "math/bits" // countLeadingOnes returns the number of leading zeros bits in x; the result is 64 for x == 0. func countLeadingZeros(x uint64) int { return bits.LeadingZeros64(x) } // countLeadingOnes returns the number of leading ones bits in x; the result is 0 for x == 0. func countLeadingOnes(x uint64) int { return bits.LeadingZeros64(^x) }