package main import "testing" func BenchmarkPopcnt1(b *testing.B) { for i := 0; i < b.N; i++ { popcnt(uint64(i)) } } var global uint64 func BenchmarkPopcnt2(b *testing.B) { var v uint64 for i := 0; i < b.N; i++ { v = popcnt(uint64(i)) } global = v }