http/httpguts: speed up ValidHeaderFieldName
Eliminate bounds checks and eschews UTF-8 decoding in ValidHeaderFieldName,
thereby doubling its speed without introducing any allocations.
Also eliminate bounds checks in IsTokenRune.
Add tests and benchmarks for both ValidHeaderFieldName and IsTokenRune.
goos: darwin
goarch: amd64
pkg: golang.org/x/net/http/httpguts
cpu: Intel(R) Core(TM) i7-6700HQ CPU @ 2.60GHz
│ before │ after │
│ sec/op │ sec/op vs base │
IsTokenRune-8 315.2n ± 0% 316.2n ± 1% ~ (p=0.245 n=20)
ValidHeaderFieldName-8 62.77n ± 0% 29.16n ± 0% -53.55% (p=0.000 n=20)
geomean 140.7n 96.02n -31.73%
│ before │ after │
│ B/op │ B/op vs base │
IsTokenRune-8 0.000 ± 0% 0.000 ± 0% ~ (p=1.000 n=20)
ValidHeaderFieldName-8 0.000 ± 0% 0.000 ± 0% ~ (p=1.000 n=20)
geomean ² +0.00%
│ before │ after │
│ allocs/op │ allocs/op vs base │
IsTokenRune-8 0.000 ± 0% 0.000 ± 0% ~ (p=1.000 n=20)
ValidHeaderFieldName-8 0.000 ± 0% 0.000 ± 0% ~ (p=1.000 n=20)
geomean ² +0.00%
Fixes golang/go#66700
Change-Id: Ia3ea80e5f0d173e3a69eb7429023587fd7bc5933
GitHub-Last-Rev: 1f1d25d1ecc34dca5d573c89d673dc634520df33
GitHub-Pull-Request: golang/net#207
Reviewed-on: https://go-review.googlesource.com/c/net/+/578075
Run-TryBot: Emmanuel Odeke <emmanuel@orijtech.com>
Reviewed-by: Damien Neil <dneil@google.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
diff --git a/http/httpguts/httplex.go b/http/httpguts/httplex.go
index 6e071e8..9b4de94 100644
--- a/http/httpguts/httplex.go
+++ b/http/httpguts/httplex.go
@@ -12,7 +12,7 @@
"golang.org/x/net/idna"
)
-var isTokenTable = [127]bool{
+var isTokenTable = [256]bool{
'!': true,
'#': true,
'$': true,
@@ -93,12 +93,7 @@
}
func IsTokenRune(r rune) bool {
- i := int(r)
- return i < len(isTokenTable) && isTokenTable[i]
-}
-
-func isNotToken(r rune) bool {
- return !IsTokenRune(r)
+ return r < utf8.RuneSelf && isTokenTable[byte(r)]
}
// HeaderValuesContainsToken reports whether any string in values
@@ -202,8 +197,8 @@
if len(v) == 0 {
return false
}
- for _, r := range v {
- if !IsTokenRune(r) {
+ for i := 0; i < len(v); i++ {
+ if !isTokenTable[v[i]] {
return false
}
}
diff --git a/http/httpguts/httplex_test.go b/http/httpguts/httplex_test.go
index a2c57f3..791440b 100644
--- a/http/httpguts/httplex_test.go
+++ b/http/httpguts/httplex_test.go
@@ -20,7 +20,7 @@
return false
}
-func TestIsToken(t *testing.T) {
+func TestIsTokenRune(t *testing.T) {
for i := 0; i <= 130; i++ {
r := rune(i)
expected := isChar(r) && !isCtl(r) && !isSeparator(r)
@@ -30,6 +30,15 @@
}
}
+func BenchmarkIsTokenRune(b *testing.B) {
+ for i := 0; i < b.N; i++ {
+ var r rune
+ for ; r < 1024; r++ {
+ IsTokenRune(r)
+ }
+ }
+}
+
func TestHeaderValuesContainsToken(t *testing.T) {
tests := []struct {
vals []string
@@ -100,6 +109,44 @@
}
}
+func TestValidHeaderFieldName(t *testing.T) {
+ tests := []struct {
+ in string
+ want bool
+ }{
+ {"", false},
+ {"Accept Charset", false},
+ {"Accept-Charset", true},
+ {"AccepT-EncodinG", true},
+ {"CONNECTION", true},
+ {"résumé", false},
+ }
+ for _, tt := range tests {
+ got := ValidHeaderFieldName(tt.in)
+ if tt.want != got {
+ t.Errorf("ValidHeaderFieldName(%q) = %t; want %t", tt.in, got, tt.want)
+ }
+ }
+}
+
+func BenchmarkValidHeaderFieldName(b *testing.B) {
+ names := []string{
+ "",
+ "Accept Charset",
+ "Accept-Charset",
+ "AccepT-EncodinG",
+ "CONNECTION",
+ "résumé",
+ }
+ b.ReportAllocs()
+ b.ResetTimer()
+ for i := 0; i < b.N; i++ {
+ for _, name := range names {
+ ValidHeaderFieldName(name)
+ }
+ }
+}
+
func TestPunycodeHostPort(t *testing.T) {
tests := []struct {
in, want string
