func BenchmarkNilCheckDeep100(b *testing.B)   { benchmarkNilCheckDeep(b, 100) }
func BenchmarkNilCheckDeep1000(b *testing.B)  { benchmarkNilCheckDeep(b, 1000) }
func BenchmarkNilCheckDeep10000(b *testing.B) { benchmarkNilCheckDeep(b, 10000) }

// benchmarkNilCheckDeep is a stress test of nilcheckelim.
// It uses the worst possible input: A linear string of
// nil checks, none of which can be eliminated.