code review 12440044: runtime: tune append crossover on amd64 and 386

src/pkg/runtime/append_test.go

 // 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.
 package runtime_test
 
 import "testing"
 
 const N = 20
 
 func BenchmarkAppend(b *testing.B) {
@@ skipping 20 matching lines @@
 }
 
 func BenchmarkAppend1Byte(b *testing.B) {
         benchmarkAppendBytes(b, 1)
 }
 
 func BenchmarkAppend4Bytes(b *testing.B) {
         benchmarkAppendBytes(b, 4)
 }
 
+func BenchmarkAppend7Bytes(b *testing.B) {
+        benchmarkAppendBytes(b, 7)
+}
+
 func BenchmarkAppend8Bytes(b *testing.B) {
         benchmarkAppendBytes(b, 8)
 }
 
+func BenchmarkAppend15Bytes(b *testing.B) {
+        benchmarkAppendBytes(b, 15)
+}
+
 func BenchmarkAppend16Bytes(b *testing.B) {
         benchmarkAppendBytes(b, 16)
 }
 
 func BenchmarkAppend32Bytes(b *testing.B) {
         benchmarkAppendBytes(b, 32)
 }
 
 func benchmarkAppendStr(b *testing.B, str string) {
         b.StopTimer()
@@ skipping 59 matching lines @@
 
 func TestAppendOverlap(t *testing.T) {
         x := []byte("1234")
         x = append(x[1:], x...) // p > q in runtime·appendslice.
         got := string(x)
         want := "2341234"
         if got != want {
                 t.Errorf("overlap failed: got %q want %q", got, want)
         }
 }