53 lines
905 B
Go
53 lines
905 B
Go
// Copyright 2011 The Go Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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package runtime_test
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import "testing"
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const N = 20
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func BenchmarkAppend(b *testing.B) {
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b.StopTimer()
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x := make([]int, 0, N)
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b.StartTimer()
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for i := 0; i < b.N; i++ {
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x = x[0:0]
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for j := 0; j < N; j++ {
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x = append(x, j)
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}
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}
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}
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func BenchmarkAppendSpecialCase(b *testing.B) {
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b.StopTimer()
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x := make([]int, 0, N)
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b.StartTimer()
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for i := 0; i < b.N; i++ {
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x = x[0:0]
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for j := 0; j < N; j++ {
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if len(x) < cap(x) {
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x = x[:len(x)+1]
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x[len(x)-1] = j
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} else {
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x = append(x, j)
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}
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}
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}
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}
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var x []int
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func f() int {
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x[:1][0] = 3
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return 2
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}
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func TestSideEffectOrder(t *testing.T) {
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x = make([]int, 0, 10)
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x = append(x, 1, f())
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if x[0] != 1 || x[1] != 2 {
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t.Error("append failed: ", x[0], x[1])
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}
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}
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