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2020-03-04bytes, strings: moves indexRabinKarp function to internal/bytealgerifan01
In order to facilitate optimization of IndexAny and LastIndexAny, this patch moves three Rabin-Karp related functions indexRabinKarp, hashStr and hashStrRev in strings package to initernal/bytealg. There are also three functions in the bytes package with the same names and functions but different parameter types. To highlight this, this patch also moves them to internal/bytealg and gives them slightly different names. Related benchmark changes on amd64 and arm64: name old time/op new time/op delta pkg:strings goos:linux goarch:amd64 Index-16 14.0ns ± 1% 14.1ns ± 2% ~ (p=0.738 n=5+5) LastIndex-16 15.5ns ± 1% 15.7ns ± 4% ~ (p=0.897 n=5+5) pkg:bytes goos:linux goarch:amd64 Index/10-16 26.5ns ± 1% 26.5ns ± 0% ~ (p=0.873 n=5+5) Index/32-16 26.2ns ± 0% 25.7ns ± 0% -1.68% (p=0.008 n=5+5) Index/4K-16 5.12µs ± 4% 5.14µs ± 2% ~ (p=0.841 n=5+5) Index/4M-16 5.44ms ± 3% 5.34ms ± 2% ~ (p=0.056 n=5+5) Index/64M-16 85.8ms ± 3% 84.6ms ± 0% -1.37% (p=0.016 n=5+5) name old speed new speed delta pkg:bytes goos:linux goarch:amd64 Index/10-16 377MB/s ± 1% 377MB/s ± 0% ~ (p=1.000 n=5+5) Index/32-16 1.22GB/s ± 1% 1.24GB/s ± 0% +1.66% (p=0.008 n=5+5) Index/4K-16 800MB/s ± 4% 797MB/s ± 2% ~ (p=0.841 n=5+5) Index/4M-16 771MB/s ± 3% 786MB/s ± 2% ~ (p=0.056 n=5+5) Index/64M-16 783MB/s ± 3% 793MB/s ± 0% +1.36% (p=0.016 n=5+5) name old time/op new time/op delta pkg:strings goos:linux goarch:arm64 Index-8 22.6ns ± 0% 22.5ns ± 0% ~ (p=0.167 n=5+5) LastIndex-8 17.5ns ± 0% 17.5ns ± 0% ~ (all equal) pkg:bytes goos:linux goarch:arm64 Index/10-8 25.0ns ± 0% 25.0ns ± 0% ~ (all equal) Index/32-8 160ns ± 0% 160ns ± 0% ~ (all equal) Index/4K-8 6.26µs ± 0% 6.26µs ± 0% ~ (p=0.167 n=5+5) Index/4M-8 6.30ms ± 0% 6.31ms ± 0% ~ (p=1.000 n=5+5) Index/64M-8 101ms ± 0% 101ms ± 0% ~ (p=0.690 n=5+5) name old speed new speed delta pkg:bytes goos:linux goarch:arm64 Index/10-8 399MB/s ± 0% 400MB/s ± 0% +0.08% (p=0.008 n=5+5) Index/32-8 200MB/s ± 0% 200MB/s ± 0% ~ (p=0.127 n=4+5) Index/4K-8 654MB/s ± 0% 654MB/s ± 0% +0.01% (p=0.016 n=5+5) Index/4M-8 665MB/s ± 0% 665MB/s ± 0% ~ (p=0.833 n=5+5) Index/64M-8 665MB/s ± 0% 665MB/s ± 0% ~ (p=0.913 n=5+5) Change-Id: Icce3bc162bb8613ac36dc963a46c51f8e82ab842 Reviewed-on: https://go-review.googlesource.com/c/go/+/208638 Run-TryBot: eric fang <eric.fang@arm.com> TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Ian Lance Taylor <iant@golang.org>
2020-02-26all: avoid string(i) where i has type intIan Lance Taylor
Instead use string(r) where r has type rune. This is in preparation for a vet warning for string(i). Updates #32479 Change-Id: Ic205269bba1bd41723950219ecfb67ce17a7aa79 Reviewed-on: https://go-review.googlesource.com/c/go/+/220844 Run-TryBot: Ian Lance Taylor <iant@golang.org> TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Akhil Indurti <aindurti@gmail.com> Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org> Reviewed-by: Toshihiro Shiino <shiino.toshihiro@gmail.com>
2020-01-15strings: update Join parameter name for clarityThomas Symborski
Change-Id: I83f806e76ef4d268b187bd273d78ceb41b7e8fa5 GitHub-Last-Rev: ee82eaae64536cecb631df328aafe2541f71d3f2 GitHub-Pull-Request: golang/go#36194 Reviewed-on: https://go-review.googlesource.com/c/go/+/211799 Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org> Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org> TryBot-Result: Gobot Gobot <gobot@golang.org>
2019-12-06strings: fix nonexistent path in commentpo3rin
There is a part in the comment that points to a non-existent file. It seems to have been overlooked in following PR. https://go-review.googlesource.com/c/go/+/98518/ Change-Id: I21dbfbd270c654d5cd7fa88d114a356862612d90 Reviewed-on: https://go-review.googlesource.com/c/go/+/210298 Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2019-10-31strings: remove a redundant and flaky part of a testBrad Fitzpatrick
Fixes #35280 Change-Id: I6fa3747ff7b92c6fcabdf8692d85e103de55859f Reviewed-on: https://go-review.googlesource.com/c/go/+/204598 Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org> Reviewed-by: Bryan C. Mills <bcmills@google.com> TryBot-Result: Gobot Gobot <gobot@golang.org>
2019-10-17cmd/compile: add -d=checkptr to validate unsafe.Pointer rulesMatthew Dempsky
This CL adds -d=checkptr as a compile-time option for adding instrumentation to check that Go code is following unsafe.Pointer safety rules dynamically. In particular, it currently checks two things: 1. When converting unsafe.Pointer to *T, make sure the resulting pointer is aligned appropriately for T. 2. When performing pointer arithmetic, if the result points to a Go heap object, make sure we can find an unsafe.Pointer-typed operand that pointed into the same object. These checks are currently disabled for the runtime, and can also be disabled through a new //go:nocheckptr annotation. The latter is necessary for functions like strings.noescape, which intentionally violate safety rules to workaround escape analysis limitations. Fixes #22218. Change-Id: If5a51273881d93048f74bcff10a3275c9c91da6a Reviewed-on: https://go-review.googlesource.com/c/go/+/162237 Run-TryBot: Matthew Dempsky <mdempsky@google.com> TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Keith Randall <khr@golang.org>
2019-09-24cmd/gofmt: fix computation of function header sizeEli Bendersky
Function sizes are computed to determine whether a function can be kept on one line or should be split to several lines. Part of the computation is the function header from the FUNC token and until the opening { token. Prior to this change, the function header size used distance from the original source position of the current token, which led to issues when the source between FUNC and the original source position was rewritten (such as whitespace being collapsed). Now we take the current output position into account, so that header size represents the reformatted source rather than the original source. The following files in the Go repository are reformatted with this change: * strings/strings_test.go * cmd/compile/internal/gc/fmt.go In both cases the reformatting is minor and seems to be correct given the heuristic to single-line functions longer than 100 columns to multiple lines. Fixes #28082 Change-Id: Ib737f6933e09b79e83715211421d5262b366ec93 Reviewed-on: https://go-review.googlesource.com/c/go/+/188818 Run-TryBot: Emmanuel Odeke <emm.odeke@gmail.com> Reviewed-by: Daniel Martí <mvdan@mvdan.cc> Reviewed-by: Emmanuel Odeke <emm.odeke@gmail.com> Reviewed-by: Robert Griesemer <gri@golang.org> TryBot-Result: Gobot Gobot <gobot@golang.org>
2019-09-21strings, bytes: clarify usage of EqualFoldsAndrew Medvedev
This clarifies meaning of "case folding" Unicode equality with more familiar "case insensitive" wording. For case folding properties see ftp://ftp.unicode.org/Public/UNIDATA/CaseFolding.txt. Fixes #33447 Change-Id: I6ee85ab398679bf2a0b7d18693985ff0979d6c5a GitHub-Last-Rev: accc9159330c61e046d77f77beac62b38bf72c19 GitHub-Pull-Request: golang/go#34434 Reviewed-on: https://go-review.googlesource.com/c/go/+/196717 Reviewed-by: Rob Pike <r@golang.org>
2019-07-30strings: clarify usage of Title and ToTitleAndrew Todd
This is intended to help clear up confusion around the usage of the Title and ToTitle functions. It includes a link to define title case to distinguish it from upper case. It also includes an additional example for the ToTitle function to showcase the difference in behavior between it and the Title function. Fixes #33302 Change-Id: I44e62962fb04d0d22966a39eda3a2d16de7a2291 Reviewed-on: https://go-review.googlesource.com/c/go/+/187825 Reviewed-by: Rob Pike <r@golang.org>
2019-07-10strings: document that order of pairs matters in NewReplacerFrancesco Renzi
Update NewReplacer documentation to specify that in the case of multiple matches at the same position, the matching old/new pair that appears first in NewReplacer arguments takes precedence. Fixes #32699 Change-Id: I9d0616d28e5cd8c9bfa301be201f2b0ebf361dff Reviewed-on: https://go-review.googlesource.com/c/go/+/185099 Reviewed-by: Ian Lance Taylor <iant@golang.org> Reviewed-by: Rob Pike <r@golang.org>
2019-05-24strings: clarify example of ContainsAnyMartin Sucha
I have seen code that literally copied the example like this: if strings.ContainsAny(s, "1 & 2 & 3") { The developer apparently thought that this is the way to specify multiple characters and I noticed this pattern being used in the example. Let's update the example so that it's clear how multiple Unicode code points should be specified. Change-Id: Id4d780555e521af62fb787a7950be1e60848cd95 Reviewed-on: https://go-review.googlesource.com/c/go/+/178737 Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org> Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org> TryBot-Result: Gobot Gobot <gobot@golang.org>
2019-05-01strings, bytes: add ToValidUTF8Martin Möhrmann
The newly added functions create a copy of their input with all bytes in invalid UTF-8 byte sequences mapped to the UTF-8 byte sequence given as replacement parameter. Fixes #25805 Change-Id: Iaf65f65b40c0581c6bb000f1590408d6628321d0 Reviewed-on: https://go-review.googlesource.com/c/go/+/142003 Run-TryBot: Martin Möhrmann <moehrmann@google.com> TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2019-04-14strings: remove "a copy of the string" from ToUpper/ToLower commentsМаксадбек Ахмедов
When string letters are all in lower/upper cases, both functions respectively return original string. Fixes #30987 Change-Id: Ie8d664f7af5e087f82c1bc156933e9a995645bf4 Reviewed-on: https://go-review.googlesource.com/c/go/+/171735 Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2019-04-09strings: add TestIndexByteTobias Klauser
Add TestIndexByte to package strings similar to the already existing TestIndexByte in package bytes. Change-Id: Ib60695cb326156a4fe48138c66393ebbd11e4a25 Reviewed-on: https://go-review.googlesource.com/c/go/+/171197 Run-TryBot: Tobias Klauser <tobias.klauser@gmail.com> TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2019-04-09strings: use Go style character range comparison in ToUpper/ToLowerTobias Klauser
As noted by Brad in CL 170954 for package bytes. Change-Id: I2772a356299e54ba5b7884d537e6649039adb9be Reviewed-on: https://go-review.googlesource.com/c/go/+/171198 Run-TryBot: Tobias Klauser <tobias.klauser@gmail.com> TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2019-04-08strings: unindent FieldsTobias Klauser
CL 56470 unindented bytes.Fields, but not strings.Fields. Do so now to make it easier to diff the two functions for potential differences. Change-Id: Ifef81f50cee64e8277e91efa5ec5521d8d21d3bd Reviewed-on: https://go-review.googlesource.com/c/go/+/170951 Run-TryBot: Tobias Klauser <tobias.klauser@gmail.com> Reviewed-by: Daniel Martí <mvdan@mvdan.cc> TryBot-Result: Gobot Gobot <gobot@golang.org>
2019-04-03strings: document that NewReplacer can panicBrad Fitzpatrick
Fixes #31233 Change-Id: I2831d5e6532d3f4ed7eb99af5d6e0e1a41ebac9a Reviewed-on: https://go-review.googlesource.com/c/go/+/170624 Reviewed-by: Andrew Bonventre <andybons@golang.org>
2019-03-29bytes, strings: add tests for TrimLeftFunc and TrimRightFuncBen Hoyt
When I was working on the fix for #31038 (make TrimSpace return nil on all-space input) I noticed that there were no tests for TrimLeftFunc and TrimRightFunc, including the funky nil behavior. So add some! I've just reused the existing TrimFunc test cases for TrimLeftFunc and TrimRightFunc, as well as adding new tests for the empty string and all-trimmed cases (which test the nil-returning behavior of TrimFunc and TrimLeftFunc). Change-Id: Ib580d4364e9b3c91350305f9d9873080d7862904 Reviewed-on: https://go-review.googlesource.com/c/go/+/170061 Run-TryBot: Ian Lance Taylor <iant@golang.org> TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Ian Lance Taylor <iant@golang.org>
2019-03-12bytes, strings: speed up TrimSpace 4-5x for common ASCII casesBen Hoyt
This change adds a fast path for ASCII strings to both strings.TrimSpace and bytes.TrimSpace. It doesn't slow down the non-ASCII path much, if at all. I added benchmarks for strings.TrimSpace as it didn't have any, and I fleshed out the benchmarks for bytes.TrimSpace as it just had one case (for ASCII). The benchmarks (and the code!) are now the same between the two versions. Below are the benchmark results: strings.TrimSpace: name old time/op new time/op delta TrimSpace/NoTrim-8 18.6ns ± 0% 3.8ns ± 0% -79.53% (p=0.000 n=5+4) TrimSpace/ASCII-8 33.5ns ± 2% 6.0ns ± 3% -82.05% (p=0.008 n=5+5) TrimSpace/SomeNonASCII-8 97.1ns ± 1% 88.6ns ± 1% -8.68% (p=0.008 n=5+5) TrimSpace/JustNonASCII-8 144ns ± 0% 143ns ± 0% ~ (p=0.079 n=4+5) bytes.TrimSpace: name old time/op new time/op delta TrimSpace/NoTrim-8 18.9ns ± 1% 4.1ns ± 1% -78.34% (p=0.008 n=5+5) TrimSpace/ASCII-8 29.9ns ± 0% 6.3ns ± 1% -79.06% (p=0.008 n=5+5) TrimSpace/SomeNonASCII-8 91.5ns ± 0% 82.3ns ± 0% -10.03% (p=0.008 n=5+5) TrimSpace/JustNonASCII-8 150ns ± 0% 150ns ± 0% ~ (all equal) Fixes #29122 Change-Id: Ica45cd86a219cadf60173ec9db260133cd1d7951 Reviewed-on: https://go-review.googlesource.com/c/go/+/152917 Reviewed-by: Daniel Martí <mvdan@mvdan.cc> Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org> Run-TryBot: Daniel Martí <mvdan@mvdan.cc> TryBot-Result: Gobot Gobot <gobot@golang.org>
2019-03-10strings: remove unnecessary strings.sTobias Klauser
There are no empty function declarations in package strings anymore, so strings.s is no longer needed. Change-Id: I16fe161a9c06804811e98af0ca074f8f46e2f49d Reviewed-on: https://go-review.googlesource.com/c/go/+/166458 Run-TryBot: Tobias Klauser <tobias.klauser@gmail.com> TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Ian Lance Taylor <iant@golang.org>
2018-12-13strings: add ReplaceAll exampledupoxy
Change-Id: I6b0d470bdedb92844943c8e5823e214d6a7471cf GitHub-Last-Rev: 4a135000ba9c23a588b960e5b2989710cc71e3e2 GitHub-Pull-Request: golang/go#29199 Reviewed-on: https://go-review.googlesource.com/c/153840 Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org> Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org> TryBot-Result: Gobot Gobot <gobot@golang.org>
2018-12-13strings: revert accidental example change from CL 153840Brad Fitzpatrick
Change-Id: I2ff29aa9909be3062fcd5f65af261f5d8c46fbc1 Reviewed-on: https://go-review.googlesource.com/c/153843 Reviewed-by: Ian Lance Taylor <iant@golang.org> Run-TryBot: Ian Lance Taylor <iant@golang.org> TryBot-Result: Gobot Gobot <gobot@golang.org>
2018-11-08strings,bytes: use inlineable function trampolines instead of linknameKeith Randall
Cleans things up quite a bit. There's still a few more, like runtime.cmpstring, which might also be worth fixing. Change-Id: Ide18dd621efc129cc686db223f47fa0b044b5580 Reviewed-on: https://go-review.googlesource.com/c/148578 Run-TryBot: Keith Randall <khr@golang.org> TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Austin Clements <austin@google.com>
2018-11-08strings: remove empty line沈涛
Change-Id: Ibdca4f7002585b00d7f69d710285a8e0f69c598a GitHub-Last-Rev: eb8f800c986c8ac4a81705158ecc730c35e1c5c2 GitHub-Pull-Request: golang/go#28659 Reviewed-on: https://go-review.googlesource.com/c/148477 Reviewed-by: Russ Cox <rsc@golang.org>
2018-11-04strings: lower running time of TestCompareStringsKeith Randall
At each comparison, we're making a copy of the whole string. Instead, use unsafe to share the string backing store with a []byte. It reduces the test time from ~4sec to ~1sec on my machine (darwin/amd64). Some builders were having much more trouble with this test (>3min), it may help more there. Fixes #26174 Fixes #28573 Fixes #26155 Update #26473 Change-Id: Id5856fd26faf6ff46e763a088f039230556a4116 Reviewed-on: https://go-review.googlesource.com/c/147358 Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2018-10-30strings: declare IndexByte as noescapeKeith Randall
This lets []byte->string conversions which are used as arguments to strings.IndexByte and friends have their backing store allocated on the stack. It only prevents allocation when the string is small enough (32 bytes), so it isn't perfect. But reusing the []byte backing store directly requires a bunch more compiler analysis (see #2205 and related issues). Fixes #25864. Change-Id: Ie52430422196e3c91e5529d6e56a8435ced1fc4c Reviewed-on: https://go-review.googlesource.com/c/146018 Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2018-10-29bytes, strings: fix Reader.UnreadRune returning without error on a zero ReaderTim Cooper
Fixes #28269 Change-Id: I878dff43c0b6bdb98702d8e73f2ecd984fb2350f Reviewed-on: https://go-review.googlesource.com/c/145098 Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org> Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org> TryBot-Result: Gobot Gobot <gobot@golang.org>
2018-10-13strings: Replace s[:] to s where s is a slice.Ivan Sharavuev
Change-Id: Ie7ba3f9ece9b0fc0e8a5c92fbae9c3b558815e4c Reviewed-on: https://go-review.googlesource.com/c/141997 Run-TryBot: Iskander Sharipov <iskander.sharipov@intel.com> TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Iskander Sharipov <iskander.sharipov@intel.com>
2018-10-03strings: correctly handle invalid utf8 sequences in MapMartin Möhrmann
When an invalid UTF-8 byte sequence is decoded in a range loop over a string a utf8.RuneError rune is returned. This is not distinguishable from decoding the valid '\uFFFD' sequence representing utf8.RuneError from a string without further checks within the range loop. The previous Map code did not do any extra checks and would thereby not map invalid UTF-8 byte sequences correctly when those were mapping to utf8.RuneError. Fix this by adding the extra checks necessary to distinguish the decoding of invalid utf8 byte sequences from decoding the sequence for utf8.RuneError when the mapping of a rune is utf8.RuneError. This fix does not result in a measureable performance regression: name old time/op new time/op delta ByteByteMap 1.05µs ± 3% 1.03µs ± 3% ~ (p=0.118 n=10+10) Map/identity/ASCII 169ns ± 2% 170ns ± 1% ~ (p=0.501 n=9+10) Map/identity/Greek 298ns ± 1% 303ns ± 4% ~ (p=0.338 n=10+10) Map/change/ASCII 323ns ± 3% 325ns ± 4% ~ (p=0.679 n=8+10) Map/change/Greek 628ns ± 5% 635ns ± 1% ~ (p=0.460 n=10+9) MapNoChanges 120ns ± 4% 119ns ± 1% ~ (p=0.496 n=10+9) Fixes #26305 Change-Id: I70e99fa244983c5040756fa4549ac1e8cb6022c3 Reviewed-on: https://go-review.googlesource.com/c/131495 Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2018-10-03io: export StringWriterDaniel Martí
And start using it elsewhere in the standard library, removing the copies in the process. While at it, rewrite the io.WriteString godoc to be more clear, since it can now make reference to the defined interface. Fixes #27946. Change-Id: Id5ba223c09c19e5fb49815bd3b1bd3254fc786f3 Reviewed-on: https://go-review.googlesource.com/c/139457 Run-TryBot: Daniel Martí <mvdan@mvdan.cc> Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org> TryBot-Result: Gobot Gobot <gobot@golang.org>
2018-09-26all: use strings.ReplaceAll and bytes.ReplaceAll where applicableBrad Fitzpatrick
I omitted vendor directories and anything necessary for bootstrapping. (Tested by bootstrapping with Go 1.4) Updates #27864 Change-Id: I7d9b68d0372d3a34dee22966cca323513ece7e8a Reviewed-on: https://go-review.googlesource.com/137856 Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org> TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Ian Lance Taylor <iant@golang.org>
2018-09-26bytes, strings: add ReplaceAllBrad Fitzpatrick
Credit to Harald Nordgren for the proposal in https://golang.org/cl/137456 and #27864. Fixes #27864 Change-Id: I80546683b0623124fe4627a71af88add2f6c1c27 Reviewed-on: https://go-review.googlesource.com/137855 Reviewed-by: Ian Lance Taylor <iant@golang.org>
2018-09-26strings: use Builder in ToUpper and ToLowerTom Thorogood
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>
2018-09-13strings, bytes: optimize function Indexerifan01
This change compares the first two characters instead of the first one, and if they match, the entire string is compared. Comparing the first two characters helps to filter out the case where the first character matches but the subsequent characters do not match, thereby improving the substring search speed in this case. Benchmarks with no effect or minimal impact (less than 5%) is not listed, the following are improved benchmarks: On arm64: strings: IndexPeriodic/IndexPeriodic16-8 172890.00ns +- 2% 124156.20ns +- 0% -28.19% (p=0.008 n=5+5) IndexPeriodic/IndexPeriodic32-8 78092.80ns +- 0% 65138.60ns +- 0% -16.59% (p=0.008 n=5+5) IndexPeriodic/IndexPeriodic64-8 42322.20ns +- 0% 34661.60ns +- 0% -18.10% (p=0.008 n=5+5) bytes: IndexPeriodic/IndexPeriodic16-8 183468.20ns +- 6% 123759.00ns +- 0% -32.54% (p=0.008 n=5+5) IndexPeriodic/IndexPeriodic32-8 84776.40ns +- 0% 63907.80ns +- 0% -24.62% (p=0.008 n=5+5) IndexPeriodic/IndexPeriodic64-8 45835.60ns +- 0% 34194.20ns +- 0% -25.40% (p=0.008 n=5+5) On amd64: strings: IndexPeriodic/IndexPeriodic8-16 219499.00ns +- 0% 178123.40ns +- 0% -18.85% (p=0.008 n=5+5) IndexPeriodic/IndexPeriodic16-16 109760.20ns +- 0% 88957.80ns +- 0% -18.95% (p=0.008 n=5+5) IndexPeriodic/IndexPeriodic32-16 54943.00ns +- 0% 44573.80ns +- 0% -18.87% (p=0.008 n=5+5) IndexPeriodic/IndexPeriodic64-16 29804.80ns +- 0% 24417.80ns +- 0% -18.07% (p=0.008 n=5+5) bytes: IndexPeriodic/IndexPeriodic8-16 226592.60ns +- 0% 181183.20ns +- 0% -20.04% (p=0.008 n=5+5) IndexPeriodic/IndexPeriodic16-16 111432.60ns +- 0% 90634.60ns +- 0% -18.66% (p=0.008 n=5+5) IndexPeriodic/IndexPeriodic32-16 55640.60ns +- 0% 45433.00ns +- 0% -18.35% (p=0.008 n=5+5) IndexPeriodic/IndexPeriodic64-16 30833.00ns +- 0% 24784.20ns +- 0% -19.62% (p=0.008 n=5+5) Change-Id: I2d9e7e138d29e960d20a203eb74dc2ec976a9d71 Reviewed-on: https://go-review.googlesource.com/131177 Run-TryBot: Ian Lance Taylor <iant@golang.org> TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Ian Lance Taylor <iant@golang.org>
2018-09-02strings: simplify Join using BuilderPhil Pearl
The existing implementation has a bunch of special cases and suffers an additional allocation for longer arrays. We can replace this code with a simple implementation using Builder, improve performance and reduce complexity. name old time/op new time/op delta Join/0-8 3.53ns ± 3% 3.72ns ± 2% +5.56% (p=0.000 n=10+10) Join/1-8 3.94ns ± 4% 3.40ns ± 4% -13.57% (p=0.000 n=10+10) Join/2-8 57.0ns ± 3% 51.0ns ± 1% -10.48% (p=0.000 n=10+9) Join/3-8 74.9ns ± 2% 65.5ns ± 4% -12.60% (p=0.000 n=10+10) Join/4-8 105ns ± 0% 79ns ± 4% -24.63% (p=0.000 n=6+10) Join/5-8 116ns ± 2% 91ns ± 4% -21.95% (p=0.000 n=10+10) Join/6-8 131ns ± 1% 104ns ± 1% -20.66% (p=0.000 n=10+10) Join/7-8 141ns ± 0% 114ns ± 4% -18.82% (p=0.000 n=9+10) name old alloc/op new alloc/op delta Join/0-8 0.00B 0.00B ~ (all equal) Join/1-8 0.00B 0.00B ~ (all equal) Join/2-8 16.0B ± 0% 16.0B ± 0% ~ (all equal) Join/3-8 32.0B ± 0% 32.0B ± 0% ~ (all equal) Join/4-8 96.0B ± 0% 48.0B ± 0% -50.00% (p=0.000 n=10+10) Join/5-8 96.0B ± 0% 48.0B ± 0% -50.00% (p=0.000 n=10+10) Join/6-8 128B ± 0% 64B ± 0% -50.00% (p=0.000 n=10+10) Join/7-8 128B ± 0% 64B ± 0% -50.00% (p=0.000 n=10+10) name old allocs/op new allocs/op delta Join/0-8 0.00 0.00 ~ (all equal) Join/1-8 0.00 0.00 ~ (all equal) Join/2-8 1.00 ± 0% 1.00 ± 0% ~ (all equal) Join/3-8 1.00 ± 0% 1.00 ± 0% ~ (all equal) Join/4-8 2.00 ± 0% 1.00 ± 0% -50.00% (p=0.000 n=10+10) Join/5-8 2.00 ± 0% 1.00 ± 0% -50.00% (p=0.000 n=10+10) Join/6-8 2.00 ± 0% 1.00 ± 0% -50.00% (p=0.000 n=10+10) Join/7-8 2.00 ± 0% 1.00 ± 0% -50.00% (p=0.000 n=10+10) Change-Id: I866a50e809c398512cb87648c955eaa4bf4d8606 Reviewed-on: https://go-review.googlesource.com/132895 Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2018-08-22strings: use Builder in Repeat to avoid an allocationgo101
name old time/op new time/op delta Repeat/5x1-4 95.9ns ± 2% 70.1ns ± 2% -26.93% (p=0.000 n=9+10) Repeat/5x2-4 146ns ± 3% 100ns ± 2% -31.99% (p=0.000 n=10+10) Repeat/5x6-4 203ns ± 3% 140ns ± 4% -30.77% (p=0.000 n=10+10) Repeat/10x1-4 139ns ± 3% 92ns ± 4% -34.08% (p=0.000 n=10+10) Repeat/10x2-4 188ns ± 4% 122ns ± 2% -35.34% (p=0.000 n=10+10) Repeat/10x6-4 264ns ± 5% 179ns ± 4% -32.15% (p=0.000 n=10+10) name old alloc/op new alloc/op delta Repeat/5x1-4 10.0B ± 0% 5.0B ± 0% -50.00% (p=0.000 n=10+10) Repeat/5x2-4 32.0B ± 0% 16.0B ± 0% -50.00% (p=0.000 n=10+10) Repeat/5x6-4 64.0B ± 0% 32.0B ± 0% -50.00% (p=0.000 n=10+10) Repeat/10x1-4 32.0B ± 0% 16.0B ± 0% -50.00% (p=0.000 n=10+10) Repeat/10x2-4 64.0B ± 0% 32.0B ± 0% -50.00% (p=0.000 n=10+10) Repeat/10x6-4 128B ± 0% 64B ± 0% -50.00% (p=0.000 n=10+10) Change-Id: I6619336da636df39c560f6cc481519f48c6e8176 GitHub-Last-Rev: 4b2c73f3bfa0b3789268b9ea6e1ecdb984e8087c GitHub-Pull-Request: golang/go#25894 Reviewed-on: https://go-review.googlesource.com/118855 Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org> TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2018-08-22strings, bytes: avoid unnecessary function literalsJohan Brandhorst
A number of explicit function literals found through the unlambda linter are removed. Fixes #26802 Change-Id: I0b122bdd95e9cb804c77efe20483fdf681c8154e Reviewed-on: https://go-review.googlesource.com/127756 Reviewed-by: Joe Tsai <thebrokentoaster@gmail.com>
2018-08-22strings: use Builder in MapMichael Fraenkel
Use a builder to avoid the copy when converting the []byte to a string. name old time/op new time/op delta ByteByteMap-8 796ns ± 5% 700ns ± 1% -12.00% (p=0.000 n=9+8) Map/identity/ASCII-8 123ns ± 8% 126ns ± 7% ~ (p=0.194 n=10+10) Map/identity/Greek-8 198ns ± 2% 204ns ± 5% +2.99% (p=0.008 n=9+10) Map/change/ASCII-8 266ns ±10% 202ns ± 3% -24.19% (p=0.000 n=10+10) Map/change/Greek-8 450ns ± 4% 406ns ± 1% -9.73% (p=0.000 n=9+10) MapNoChanges-8 85.4ns ± 3% 90.2ns ±11% +5.67% (p=0.000 n=9+10) name old alloc/op new alloc/op delta ByteByteMap-8 416B ± 0% 208B ± 0% -50.00% (p=0.000 n=10+10) Map/identity/ASCII-8 0.00B 0.00B ~ (all equal) Map/identity/Greek-8 0.00B 0.00B ~ (all equal) Map/change/ASCII-8 128B ± 0% 64B ± 0% -50.00% (p=0.000 n=10+10) Map/change/Greek-8 160B ± 0% 80B ± 0% -50.00% (p=0.000 n=10+10) MapNoChanges-8 0.00B 0.00B ~ (all equal) name old allocs/op new allocs/op delta ByteByteMap-8 2.00 ± 0% 1.00 ± 0% -50.00% (p=0.000 n=10+10) Map/identity/ASCII-8 0.00 0.00 ~ (all equal) Map/identity/Greek-8 0.00 0.00 ~ (all equal) Map/change/ASCII-8 2.00 ± 0% 1.00 ± 0% -50.00% (p=0.000 n=10+10) Map/change/Greek-8 2.00 ± 0% 1.00 ± 0% -50.00% (p=0.000 n=10+10) MapNoChanges-8 0.00 0.00 ~ (all equal) Fixes #26304 Change-Id: Ideec9dfc29b0b8107f34fc634247081d0031777d Reviewed-on: https://go-review.googlesource.com/122875 Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2018-08-21strings: revise ToUpperSpecial and ToLowerSpecial wordingKevin Zita
Fixes #26654 Change-Id: I4832c45cad40607b83e1a8a9b562fa12e639b7d9 GitHub-Last-Rev: c9ceedb7d4b4c01f91ea4fe3dc3496e73eed9120 GitHub-Pull-Request: golang/go#26781 Reviewed-on: https://go-review.googlesource.com/127716 Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2018-08-21strings: select Replacer algorithm and build machine lazilyBrad Fitzpatrick
Saves 22KB of memory in stdlib packages. Updates #26775 Change-Id: Ia19fe7aff61f6e2ddd83cd35969d7ff94526591f Reviewed-on: https://go-review.googlesource.com/127661 Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org> TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Ian Lance Taylor <iant@golang.org>
2018-08-20strings: add Builder.CapDaniel Martí
To report the capacity of the underlying buffer. The method mirrors bytes.Buffer.Cap. The method can be useful to know whether or not calling write or grow methods will result in an allocation, or to know how much memory has been allocated so far. Fixes #26269. Change-Id: I391db45ae825011566b594836991e28135369a78 Reviewed-on: https://go-review.googlesource.com/122835 Run-TryBot: Daniel Martí <mvdan@mvdan.cc> TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2018-07-02strings: do much less redundant testing in TestCompareStringsIan Lance Taylor
On the OpenBSD builder this reduces the test time from 213 seconds to 60 seconds, without loss of testing. Not sure why the test is so much slower on OpenBSD, so not closing the issues. Updates #26155 Updates #26174 Change-Id: I13b58bbe3b209e591c308765077d2342943a3d2a Reviewed-on: https://go-review.googlesource.com/121820 Run-TryBot: Ian Lance Taylor <iant@golang.org> TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Ralph Corderoy <ralph@inputplus.co.uk> Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2018-06-29bytes, strings: fix comparison of long byte slices on s390xbill_ofarrell
The existing implementation of bytes.Compare on s390x doesn't work properly for slices longer than 256 elements. This change fixes that. Added tests for long strings and slices of bytes. Fixes #26114 Change-Id: If6d8b68ee6dbcf99a24f867a1d3438b1f208954f Reviewed-on: https://go-review.googlesource.com/121495 Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org> Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org> TryBot-Result: Gobot Gobot <gobot@golang.org>
2018-06-29strings: add note for new Go developers to TrimLeft and TrimRightDaniel Martí
If one quickly looks at the strings package godoc, reading the name TrimLeft, one might think it removes a prefix from the string. The function's godoc does explain its purpose, but it's apparent that it is not clear enough, as there have been numerous raised issues about this confusion: #12771 #14657 #18160 #19371 #20085 #25328 #26119. These questions are also frequent elsewhere on the internet. Add a very short paragraph to the godoc, to hopefully point new Go developers in the right direction faster. Do the same thing for TrimRight and TrimSuffix. Change-Id: I4dee5ed8dd9fba565b4755bad12ae1ee6d277959 Reviewed-on: https://go-review.googlesource.com/121637 Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2018-06-01all: update comment URLs from HTTP to HTTPS, where possibleTim Cooper
Each URL was manually verified to ensure it did not serve up incorrect content. Change-Id: I4dc846227af95a73ee9a3074d0c379ff0fa955df Reviewed-on: https://go-review.googlesource.com/115798 Reviewed-by: Ian Lance Taylor <iant@golang.org> Run-TryBot: Ian Lance Taylor <iant@golang.org>
2018-05-04strings: fix encoding of \u0080 in mapMartin Möhrmann
Fix encoding of PAD (U+0080) which has the same value as utf8.RuneSelf being incorrectly encoded as \x80 in strings.Map due to using <= instead of a < comparison operator to check one byte encodings for utf8. Fixes #25242 Change-Id: Ib6c7d1f425a7ba81e431b6d64009e713d94ea3bc Reviewed-on: https://go-review.googlesource.com/111286 Run-TryBot: Martin Möhrmann <moehrmann@google.com> TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2018-05-01bytes, strings: improve EqualFold fast version for ASCIIEric Pauley
The existing implementation only considers the special ASCII case when the lower character is an upper case letter. This means that most ASCII comparisons use unicode.SimpleFold even when it is not necessary. benchmark old ns/op new ns/op delta BenchmarkEqualFold-8 450 390 -13.33% Change-Id: I735ca3c30fc0145c186d2a54f31fd39caab2c3fa Reviewed-on: https://go-review.googlesource.com/110018 Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2018-04-26strings: clarify Replacer's replacement orderAlberto Donizetti
NewReplacer's documentation says that "replacements are performed in order", meaning that substrings are replaced in the order they appear in the target string, and not that the old->new replacements are applied in the order they're passed to NewReplacer. Rephrase the doc to make this clearer. Fixes #25071 Change-Id: Icf3aa6a9d459b94764c9d577e4a76ad8c04d158d Reviewed-on: https://go-review.googlesource.com/109375 Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2018-04-03strings: fix flaky TestBuilderGrow testBrad Fitzpatrick
Fixes #24647 Change-Id: I79c2b45cf7fc9c0ed0c7a665472556bd248e7584 Reviewed-on: https://go-review.googlesource.com/104235 Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org> TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Bryan Mills <bcmills@google.com> Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
2018-04-02strings: speed-up replace for byteStringReplacer caseIlya Tocar
Use Count instead of loop to determine a number of replacements. Also increment index instead of advancing slices, to avoid some extra stores. Shows very significant speed-up on html benchmarks: Escape-6 34.2µs ± 2% 20.8µs ± 2% -39.06% (p=0.000 n=10+10) EscapeNone-6 7.04µs ± 1% 1.05µs ± 0% -85.03% (p=0.000 n=10+10) On benchmarks in package strings results are still significant: ByteStringMatch-6 1.59µs ± 2% 1.17µs ± 2% -26.35% (p=0.000 n=10+10) HTMLEscapeNew-6 390ns ± 2% 337ns ± 2% -13.62% (p=0.000 n=10+10) HTMLEscapeOld-6 621ns ± 2% 603ns ± 2% -2.95% (p=0.000 n=10+9) Change-Id: Ibea3235b6e451ba72cd5db57716d17b917e72944 Reviewed-on: https://go-review.googlesource.com/97255 Run-TryBot: Ilya Tocar <ilya.tocar@intel.com> TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
generated by cgit v1.3 (git 2.53.0) at 2026-04-15 14:47:05 +0000