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// $G -N -o slow.$A $D/bug369.dir/pkg.go &&
// $G -o fast.$A $D/bug369.dir/pkg.go &&
// run
// Copyright 2011 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// Test that compiling with optimization turned on produces faster code.
package main
import (
"flag"
"os"
"runtime"
"testing"
fast "./fast"
slow "./slow"
)
var buf = make([]byte, 1048576)
func BenchmarkFastNonASCII(b *testing.B) {
for i := 0; i < b.N; i++ {
fast.NonASCII(buf, 0)
}
}
func BenchmarkSlowNonASCII(b *testing.B) {
for i := 0; i < b.N; i++ {
slow.NonASCII(buf, 0)
}
}
func main() {
os.Args = []string{os.Args[0], "-test.benchtime=0.1"}
flag.Parse()
rslow := testing.Benchmark(BenchmarkSlowNonASCII)
rfast := testing.Benchmark(BenchmarkFastNonASCII)
tslow := rslow.NsPerOp()
tfast := rfast.NsPerOp()
// Optimization should be good for at least 2x, but be forgiving.
// On the ARM simulator we see closer to 1.5x.
speedup := float64(tslow)/float64(tfast)
want := 1.8
if runtime.GOARCH == "arm" {
want = 1.3
}
if speedup < want {
// TODO(rsc): doesn't work on linux-amd64 or darwin-amd64 builders, nor on
// a Lenovo x200 (linux-amd64) laptop.
//println("fast:", tfast, "slow:", tslow, "speedup:", speedup, "want:", want)
//println("not fast enough")
}
}
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