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| author | Tom Thorogood <me+google@tomthorogood.co.uk> | 2018-09-26 11:29:18 +0000 |
|---|---|---|
| committer | Brad Fitzpatrick <bradfitz@golang.org> | 2018-09-26 14:41:52 +0000 |
| commit | 14e7f174c1bfb80192274b049487716cdde0b4ee (patch) | |
| tree | f24c2d7dd12de04bbe0d41bbc74db90245a99703 /src/strings | |
| parent | 1058aecf611fc85365f87733f8588ef1cd31c8cd (diff) | |
| download | go-14e7f174c1bfb80192274b049487716cdde0b4ee.tar.gz go-14e7f174c1bfb80192274b049487716cdde0b4ee.zip | |
strings: use Builder in ToUpper and ToLower
Map was optimized to use Builder in 45c7d80832, which avoided the []byte
to string converstion. This left the ToUpper and ToLower ASCII fast path
with an extra allocation over Map.
name old time/op new time/op delta
ToUpper/#00-12 3.59ns ± 4% 3.71ns ± 1% ~ (p=0.056 n=5+5)
ToUpper/ONLYUPPER-12 11.8ns ± 2% 10.5ns ± 2% -10.85% (p=0.008 n=5+5)
ToUpper/abc-12 31.8ns ± 1% 25.3ns ± 1% -20.40% (p=0.008 n=5+5)
ToUpper/AbC123-12 46.2ns ± 7% 31.9ns ± 8% -30.89% (p=0.008 n=5+5)
ToUpper/azAZ09_-12 47.1ns ± 8% 32.6ns ± 4% -30.77% (p=0.008 n=5+5)
ToUpper/longStrinGwitHmixofsmaLLandcAps-12 137ns ±15% 104ns ±11% -24.11% (p=0.008 n=5+5)
ToUpper/longɐstringɐwithɐnonasciiⱯchars-12 231ns ± 1% 228ns ± 1% ~ (p=0.079 n=5+5)
ToUpper/ɐɐɐɐɐ-12 207ns ± 3% 206ns ± 1% ~ (p=0.913 n=5+5)
ToUpper/a\u0080\U0010ffff-12 90.8ns ± 1% 89.6ns ± 1% -1.30% (p=0.024 n=5+5)
ToLower/#00-12 3.59ns ± 1% 4.26ns ± 2% +18.66% (p=0.008 n=5+5)
ToLower/abc-12 6.32ns ± 1% 6.62ns ± 1% +4.72% (p=0.008 n=5+5)
ToLower/AbC123-12 45.0ns ±13% 31.5ns ± 4% -29.89% (p=0.008 n=5+5)
ToLower/azAZ09_-12 48.8ns ± 6% 33.2ns ± 3% -31.91% (p=0.008 n=5+5)
ToLower/longStrinGwitHmixofsmaLLandcAps-12 149ns ±13% 98ns ± 8% -34.30% (p=0.008 n=5+5)
ToLower/LONGⱯSTRINGⱯWITHⱯNONASCIIⱯCHARS-12 237ns ± 4% 237ns ± 2% ~ (p=0.635 n=5+5)
ToLower/ⱭⱭⱭⱭⱭ-12 181ns ± 1% 181ns ± 1% ~ (p=0.762 n=5+5)
ToLower/A\u0080\U0010ffff-12 90.6ns ± 1% 92.5ns ± 1% +2.05% (p=0.016 n=5+5)
name old alloc/op new alloc/op delta
ToUpper/#00-12 0.00B 0.00B ~ (all equal)
ToUpper/ONLYUPPER-12 0.00B 0.00B ~ (all equal)
ToUpper/abc-12 6.00B ± 0% 3.00B ± 0% -50.00% (p=0.008 n=5+5)
ToUpper/AbC123-12 16.0B ± 0% 8.0B ± 0% -50.00% (p=0.008 n=5+5)
ToUpper/azAZ09_-12 16.0B ± 0% 8.0B ± 0% -50.00% (p=0.008 n=5+5)
ToUpper/longStrinGwitHmixofsmaLLandcAps-12 64.0B ± 0% 32.0B ± 0% -50.00% (p=0.008 n=5+5)
ToUpper/longɐstringɐwithɐnonasciiⱯchars-12 48.0B ± 0% 48.0B ± 0% ~ (all equal)
ToUpper/ɐɐɐɐɐ-12 48.0B ± 0% 48.0B ± 0% ~ (all equal)
ToUpper/a\u0080\U0010ffff-12 16.0B ± 0% 16.0B ± 0% ~ (all equal)
ToLower/#00-12 0.00B 0.00B ~ (all equal)
ToLower/abc-12 0.00B 0.00B ~ (all equal)
ToLower/AbC123-12 16.0B ± 0% 8.0B ± 0% -50.00% (p=0.008 n=5+5)
ToLower/azAZ09_-12 16.0B ± 0% 8.0B ± 0% -50.00% (p=0.008 n=5+5)
ToLower/longStrinGwitHmixofsmaLLandcAps-12 64.0B ± 0% 32.0B ± 0% -50.00% (p=0.008 n=5+5)
ToLower/LONGⱯSTRINGⱯWITHⱯNONASCIIⱯCHARS-12 48.0B ± 0% 48.0B ± 0% ~ (all equal)
ToLower/ⱭⱭⱭⱭⱭ-12 32.0B ± 0% 32.0B ± 0% ~ (all equal)
ToLower/A\u0080\U0010ffff-12 16.0B ± 0% 16.0B ± 0% ~ (all equal)
name old allocs/op new allocs/op delta
ToUpper/#00-12 0.00 0.00 ~ (all equal)
ToUpper/ONLYUPPER-12 0.00 0.00 ~ (all equal)
ToUpper/abc-12 2.00 ± 0% 1.00 ± 0% -50.00% (p=0.008 n=5+5)
ToUpper/AbC123-12 2.00 ± 0% 1.00 ± 0% -50.00% (p=0.008 n=5+5)
ToUpper/azAZ09_-12 2.00 ± 0% 1.00 ± 0% -50.00% (p=0.008 n=5+5)
ToUpper/longStrinGwitHmixofsmaLLandcAps-12 2.00 ± 0% 1.00 ± 0% -50.00% (p=0.008 n=5+5)
ToUpper/longɐstringɐwithɐnonasciiⱯchars-12 1.00 ± 0% 1.00 ± 0% ~ (all equal)
ToUpper/ɐɐɐɐɐ-12 2.00 ± 0% 2.00 ± 0% ~ (all equal)
ToUpper/a\u0080\U0010ffff-12 1.00 ± 0% 1.00 ± 0% ~ (all equal)
ToLower/#00-12 0.00 0.00 ~ (all equal)
ToLower/abc-12 0.00 0.00 ~ (all equal)
ToLower/AbC123-12 2.00 ± 0% 1.00 ± 0% -50.00% (p=0.008 n=5+5)
ToLower/azAZ09_-12 2.00 ± 0% 1.00 ± 0% -50.00% (p=0.008 n=5+5)
ToLower/longStrinGwitHmixofsmaLLandcAps-12 2.00 ± 0% 1.00 ± 0% -50.00% (p=0.008 n=5+5)
ToLower/LONGⱯSTRINGⱯWITHⱯNONASCIIⱯCHARS-12 1.00 ± 0% 1.00 ± 0% ~ (all equal)
ToLower/ⱭⱭⱭⱭⱭ-12 1.00 ± 0% 1.00 ± 0% ~ (all equal)
ToLower/A\u0080\U0010ffff-12 1.00 ± 0% 1.00 ± 0% ~ (all equal)
Updates #26304
Change-Id: I4179e21d5e60d950b925fe3ffc74b376b82812d2
GitHub-Last-Rev: 2c7c3bb75b8fb16fed5f0c8979ee9941675ed6bf
GitHub-Pull-Request: golang/go#27872
Reviewed-on: https://go-review.googlesource.com/137575
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Diffstat (limited to 'src/strings')
| -rw-r--r-- | src/strings/strings.go | 14 |
1 files changed, 8 insertions, 6 deletions
diff --git a/src/strings/strings.go b/src/strings/strings.go index 26aceda212..b033c38e91 100644 --- a/src/strings/strings.go +++ b/src/strings/strings.go @@ -561,15 +561,16 @@ func ToUpper(s string) string { if !hasLower { return s } - b := make([]byte, len(s)) + var b Builder + b.Grow(len(s)) for i := 0; i < len(s); i++ { c := s[i] if c >= 'a' && c <= 'z' { c -= 'a' - 'A' } - b[i] = c + b.WriteByte(c) } - return string(b) + return b.String() } return Map(unicode.ToUpper, s) } @@ -590,15 +591,16 @@ func ToLower(s string) string { if !hasUpper { return s } - b := make([]byte, len(s)) + var b Builder + b.Grow(len(s)) for i := 0; i < len(s); i++ { c := s[i] if c >= 'A' && c <= 'Z' { c += 'a' - 'A' } - b[i] = c + b.WriteByte(c) } - return string(b) + return b.String() } return Map(unicode.ToLower, s) } |