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| author | Martin Möhrmann <moehrmann@google.com> | 2017-03-10 20:55:51 +0100 |
|---|---|---|
| committer | Martin Möhrmann <moehrmann@google.com> | 2017-08-14 12:25:45 +0000 |
| commit | 629b5e7561ab10cb11b47e3818dd861f8a030a26 (patch) | |
| tree | ca25d0b7ad233ea3d50e449d6e942e727c65354d /src/fmt | |
| parent | 6661cf6dfd91dc3dd5d233e8bdb9f2d60829c68e (diff) | |
| download | go-git-629b5e7561ab10cb11b47e3818dd861f8a030a26.tar.gz | |
fmt: add ascii fast path for decoding verbs
name old time/op new time/op delta
SprintfSlowParsingPath 108ns ± 4% 103ns ± 4% -4.53% (p=0.000 n=18+18)
Change-Id: I174463f303d1857e8d5b8a6283c025b3546e7b39
Reviewed-on: https://go-review.googlesource.com/44450
Run-TryBot: Martin Möhrmann <moehrmann@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Rob Pike <r@golang.org>
Diffstat (limited to 'src/fmt')
| -rw-r--r-- | src/fmt/fmt_test.go | 8 | ||||
| -rw-r--r-- | src/fmt/print.go | 7 |
2 files changed, 13 insertions, 2 deletions
diff --git a/src/fmt/fmt_test.go b/src/fmt/fmt_test.go index 9bec6f3f9e..e6239a51ba 100644 --- a/src/fmt/fmt_test.go +++ b/src/fmt/fmt_test.go @@ -1201,6 +1201,14 @@ func BenchmarkSprintfTruncateString(b *testing.B) { }) } +func BenchmarkSprintfSlowParsingPath(b *testing.B) { + b.RunParallel(func(pb *testing.PB) { + for pb.Next() { + Sprintf("%.v", nil) + } + }) +} + func BenchmarkSprintfQuoteString(b *testing.B) { b.RunParallel(func(pb *testing.PB) { for pb.Next() { diff --git a/src/fmt/print.go b/src/fmt/print.go index 2bd88f95a2..d1c99c1cd3 100644 --- a/src/fmt/print.go +++ b/src/fmt/print.go @@ -1067,8 +1067,11 @@ formatLoop: break } - verb, w := utf8.DecodeRuneInString(format[i:]) - i += w + verb, size := rune(format[i]), 1 + if verb >= utf8.RuneSelf { + verb, size = utf8.DecodeRuneInString(format[i:]) + } + i += size switch { case verb == '%': // Percent does not absorb operands and ignores f.wid and f.prec. |