unicode/utf16: add benchmarks

For #6957

Change-Id: Ic497c12f33efc933e9fe81f6cd1b2a0a01abbabf
Reviewed-on: https://go-review.googlesource.com/19820
Run-TryBot: Brad Fitzpatrick <[email protected]>
TryBot-Result: Gobot Gobot <[email protected]>
Reviewed-by: Brad Fitzpatrick <[email protected]>

src/unicode/utf16/utf16_test.go

@@ -147,3 +147,56 @@ func TestIsSurrogate(t *testing.T) {
  }
  }
 }
+
+func BenchmarkDecodeValidASCII(b *testing.B) {
+ // "hello world"
+ data := []uint16{104, 101, 108, 108, 111, 32, 119, 111, 114, 108, 100}
+ for i := 0; i < b.N; i++ {
+ Decode(data)
+ }
+}
+
+func BenchmarkDecodeValidJapaneseChars(b *testing.B) {
+ // "日本語日本語日本語"
+ data := []uint16{26085, 26412, 35486, 26085, 26412, 35486, 26085, 26412, 35486}
+ for i := 0; i < b.N; i++ {
+ Decode(data)
+ }
+}
+
+func BenchmarkDecodeRune(b *testing.B) {
+ rs := make([]rune, 10)
+ // U+1D4D0 to U+1D4D4: MATHEMATICAL BOLD SCRIPT CAPITAL LETTERS
+ for i, u := range []rune{'𝓐', '𝓑', '𝓒', '𝓓', '𝓔'} {
+ rs[2*i], rs[2*i+1] = EncodeRune(u)
+ }
+
+ b.ResetTimer()
+ for i := 0; i < b.N; i++ {
+ for j := 0; j < 5; j++ {
+ DecodeRune(rs[2*j], rs[2*j+1])
+ }
+ }
+}
+
+func BenchmarkEncodeValidASCII(b *testing.B) {
+ data := []rune{'h', 'e', 'l', 'l', 'o'}
+ for i := 0; i < b.N; i++ {
+ Encode(data)
+ }
+}
+
+func BenchmarkEncodeValidJapaneseChars(b *testing.B) {
+ data := []rune{'日', '本', '語'}
+ for i := 0; i < b.N; i++ {
+ Encode(data)
+ }
+}
+
+func BenchmarkEncodeRune(b *testing.B) {
+ for i := 0; i < b.N; i++ {
+ for _, u := range []rune{'𝓐', '𝓑', '𝓒', '𝓓', '𝓔'} {
+ EncodeRune(u)
+ }
+ }
+}