Commit Graph

220 Commits

Author SHA1 Message Date
Julien Cretel 44fef2aa4d bytes: speed up Replace
This CL is to package bytes what CL 657935 was to package strings.

Add fuzz test and benchmarks for Replace.

The length of parameter old does not change. Move the corresponding length
check outside the loop. Use range-over-int loops where possible.

Some benchmark results (no changes to allocations):

goos: darwin
goarch: amd64
pkg: bytes
cpu: Intel(R) Core(TM) i7-6700HQ CPU @ 2.60GHz
                                 │     old      │                 new                 │
                                 │    sec/op    │   sec/op     vs base                │
Replace/"hello"_"l"_"L"_0-8         27.83n ± 2%   27.22n ± 1%   -2.17% (p=0.000 n=20)
Replace/"hello"_"l"_"L"_-1-8        60.64n ± 0%   57.97n ± 1%   -4.40% (p=0.000 n=20)
Replace/"hello"_"x"_"X"_-1-8        33.99n ± 0%   33.88n ± 0%        ~ (p=0.140 n=20)
Replace/""_"x"_"X"_-1-8             10.40n ± 1%   10.57n ± 0%   +1.64% (p=0.000 n=20)
Replace/"radar"_"r"_"<r>"_-1-8      62.63n ± 0%   61.39n ± 0%   -1.98% (p=0.000 n=20)
Replace/""_""_"<>"_-1-8             29.76n ± 1%   24.18n ± 1%  -18.75% (p=0.000 n=20)
Replace/"banana"_"a"_"<>"_-1-8      77.00n ± 0%   77.10n ± 1%        ~ (p=0.525 n=20)
Replace/"banana"_"a"_"<>"_1-8       44.24n ± 0%   43.57n ± 1%   -1.54% (p=0.000 n=20)
Replace/"banana"_"a"_"<>"_1000-8    78.23n ± 0%   77.16n ± 1%   -1.36% (p=0.000 n=20)
Replace/"banana"_"an"_"<>"_-1-8     72.78n ± 1%   69.97n ± 1%   -3.85% (p=0.000 n=20)
Replace/"banana"_"ana"_"<>"_-1-8    54.41n ± 0%   54.04n ± 1%   -0.67% (p=0.033 n=20)
Replace/"banana"_""_"<>"_-1-8       116.8n ± 1%   103.5n ± 1%  -11.42% (p=0.000 n=20)
Replace/"banana"_""_"<>"_10-8       117.2n ± 1%   103.6n ± 0%  -11.60% (p=0.000 n=20)
Replace/"banana"_""_"<>"_6-8       105.30n ± 0%   92.50n ± 0%  -12.16% (p=0.000 n=20)
Replace/"banana"_""_"<>"_5-8        91.81n ± 0%   79.87n ± 1%  -13.01% (p=0.000 n=20)
Replace/"banana"_""_"<>"_1-8        35.87n ± 1%   30.33n ± 1%  -15.43% (p=0.000 n=20)
Replace/"banana"_"a"_"a"_-1-8       70.84n ± 0%   68.83n ± 0%   -2.84% (p=0.000 n=20)
Replace/"banana"_"a"_"a"_1-8        44.27n ± 1%   43.47n ± 1%   -1.80% (p=0.000 n=20)
Replace/"☺☻☹"_""_"<>"_-1-8         104.25n ± 1%   93.33n ± 0%  -10.48% (p=0.000 n=20)
geomean                             56.31n        52.88n        -6.09%

Change-Id: I5daf44ccfd887da445d8c681415c32de7c2b85d1
GitHub-Last-Rev: d1caf1f084
GitHub-Pull-Request: golang/go#72967
Reviewed-on: https://go-review.googlesource.com/c/go/+/659515
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Auto-Submit: Jorropo <jorropo.pgm@gmail.com>
Reviewed-by: Jorropo <jorropo.pgm@gmail.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
2025-03-25 13:02:53 -07:00
Sean Liao bfb27fb36f bytes,strings: document Fields trimming of leading and trailing characters
Fixes #72841

Change-Id: I46875c61e3147c69da759bf4bf4f0539cbd4f437
Reviewed-on: https://go-review.googlesource.com/c/go/+/658218
Reviewed-by: Alan Donovan <adonovan@google.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
2025-03-18 15:12:18 -07:00
Jes Cok 3c05790d48 bytes,strings: remove redundant return statement for Lines
To make it more idiomatic.

Change-Id: If48ae9931908e515df7f23185aac6f84aac72084
GitHub-Last-Rev: 525ed5031a
GitHub-Pull-Request: golang/go#71838
Reviewed-on: https://go-review.googlesource.com/c/go/+/650595
Auto-Submit: Keith Randall <khr@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Commit-Queue: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Keith Randall <khr@google.com>
Auto-Submit: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Robert Griesemer <gri@google.com>
Auto-Submit: Robert Griesemer <gri@google.com>
Commit-Queue: Robert Griesemer <gri@google.com>
2025-02-19 10:22:08 -08:00
cuishuang 2299a4289d bytes: add examples for Lines, SplitSeq, SplitAfterSeq, FieldsSeq and FieldsFuncSeq
Change-Id: I0e755d5c73f14d2c98853bdd31a7f2e84c92a906
Reviewed-on: https://go-review.googlesource.com/c/go/+/648860
Reviewed-by: Ian Lance Taylor <iant@google.com>
Auto-Submit: Ian Lance Taylor <iant@google.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
2025-02-14 15:18:41 -08:00
Cherry Mui ff27d270c9 bytes: use "subslice" instead of "substring" in doc comments
The bytes package iterators return subslices, not substrings.

Updates #61901.

Change-Id: Ida91d3e33a0f178edfe9a267861adf4f13f9a965
Reviewed-on: https://go-review.googlesource.com/c/go/+/647875
Reviewed-by: Ian Lance Taylor <iant@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
2025-02-09 13:15:13 -08:00
Oleksandr Redko b057b8872d bytes, strings: add cross-references in docstrings
For newly funcs SplitSeq, SplitAfterSeq, FieldsSeq, FieldsFuncSeq.

Updates #61901.

Change-Id: I3c97bfd9c2250de68aaea348c82a05635ee797af
Reviewed-on: https://go-review.googlesource.com/c/go/+/637176
Auto-Submit: Ian Lance Taylor <iant@google.com>
Reviewed-by: Robert Griesemer <gri@google.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
2024-12-17 11:08:32 -08:00
Keith Randall 4b30a40d88 strings,bytes: use result of copy in subsequent slicing
This can get rid of a bounds check.
Followup to CL 622240.

Change-Id: I9d0a2c0408b8d274c46136d32d7a5fb09b4aad1c
Reviewed-on: https://go-review.googlesource.com/c/go/+/622955
Reviewed-by: David Chase <drchase@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>
2024-10-29 16:47:05 +00:00
nlwkobe30 7cd0a4be5c all: omit unnecessary 0 in slice expression
All changes are related to the code, except for the comments in src/regexp/syntax/parse.go and src/slices/slices.go.

Change-Id: I73c5d3c54099749b62210aa7f3182c5eb84bb6a6
GitHub-Last-Rev: 794aa9b053
GitHub-Pull-Request: golang/go#69170
Reviewed-on: https://go-review.googlesource.com/c/go/+/609678
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>
Auto-Submit: Ian Lance Taylor <iant@google.com>
2024-09-03 20:55:15 +00:00
Jes Cok 96d8ff00c2 bytes: fix a typo
Change-Id: Iecbfe986da386b5c9b8c366904f659acc8f34cfc
GitHub-Last-Rev: ed6c744bbd
GitHub-Pull-Request: golang/go#69039
Reviewed-on: https://go-review.googlesource.com/c/go/+/608015
Reviewed-by: Ian Lance Taylor <iant@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
Auto-Submit: Ian Lance Taylor <iant@google.com>
2024-08-24 00:51:40 +00:00
Oleksandr Redko d5f7da7987 all: remove duplicated words in comments
Change-Id: Id991ec0826a4e2857f00330b4b7ff2b71907b789
Reviewed-on: https://go-review.googlesource.com/c/go/+/606615
Auto-Submit: Ian Lance Taylor <iant@google.com>
Reviewed-by: Robert Griesemer <gri@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>
Auto-Submit: Robert Griesemer <gri@google.com>
Commit-Queue: Ian Lance Taylor <iant@google.com>
2024-08-19 19:09:04 +00:00
Charlie Vieth 65a6e05070 byte,strings: improve IndexRune performance by ~45%
Change IndexRune to search for the last byte of a multi-byte rune
instead of using the first byte. This improves search performance
by 45% on average when dealing with Unicode text.

The rationale here is that the last byte of a UTF-8 encoded multi-byte
rune is significantly more unique (evenly distributed) than the first
byte which has a 78% chance of being [240, 243, 244].

This approach is typically much faster, but can be slower when there
are a large number of false positives (see Han benchmarks) because
the more even distribution of bytes can delay/prevent falling back
to a brute-force search using bytealg.Index, which is particularly
powerful on amd64/x86_64 (particularly Skylake, but less so with
newer processors).

bytes package benchmarks:

goos: darwin
goarch: arm64
pkg: bytes
cpu: Apple M1 Max
                                 │ base.10.txt  │             new.10.txt              │
                                 │    sec/op    │   sec/op     vs base                │
IndexRune/10-10                     9.784n ± 0%   8.470n ± 0%  -13.43% (p=0.000 n=10)
IndexRune/32-10                    11.660n ± 0%   8.473n ± 0%  -27.34% (p=0.000 n=10)
IndexRune/4K-10                     83.96n ± 0%   81.08n ± 0%   -3.44% (p=0.000 n=10)
IndexRune/4M-10                     63.92µ ± 0%   64.67µ ± 0%   +1.17% (p=0.000 n=10)
IndexRune/64M-10                    1.121m ± 1%   1.125m ± 1%        ~ (p=0.218 n=10)
IndexRuneUnicode/Latin/10-10       10.125n ± 0%   7.347n ± 0%  -27.43% (p=0.000 n=10)
IndexRuneUnicode/Latin/32-10       11.435n ± 0%   7.349n ± 0%  -35.73% (p=0.000 n=10)
IndexRuneUnicode/Latin/4K-10        882.6n ± 0%   334.9n ± 1%  -62.06% (p=0.000 n=10)
IndexRuneUnicode/Latin/4M-10        977.2µ ± 0%   370.9µ ± 1%  -62.04% (p=0.000 n=10)
IndexRuneUnicode/Latin/64M-10      15.649m ± 1%   6.028m ± 1%  -61.48% (p=0.000 n=10)
IndexRuneUnicode/Cyrillic/10-10    10.070n ± 0%   8.701n ± 0%  -13.59% (p=0.000 n=10)
IndexRuneUnicode/Cyrillic/32-10    19.045n ± 0%   8.704n ± 1%  -54.30% (p=0.000 n=10)
IndexRuneUnicode/Cyrillic/4K-10     2.734µ ± 0%   1.046µ ± 1%  -61.75% (p=0.000 n=10)
IndexRuneUnicode/Cyrillic/4M-10     2.671m ± 0%   1.143m ± 1%  -57.22% (p=0.000 n=10)
IndexRuneUnicode/Cyrillic/64M-10    43.12m ± 1%   18.26m ± 1%  -57.64% (p=0.000 n=10)
IndexRuneUnicode/Han/10-10          10.10n ± 0%   10.82n ± 1%   +7.08% (p=0.000 n=10)
IndexRuneUnicode/Han/32-10          38.29n ± 1%   10.87n ± 1%  -71.62% (p=0.000 n=10)
IndexRuneUnicode/Han/4K-10         1409.0n ± 0%   489.1n ± 1%  -65.28% (p=0.000 n=10)
IndexRuneUnicode/Han/4M-10         1338.4µ ± 0%   821.1µ ± 2%  -38.65% (p=0.000 n=10)
IndexRuneUnicode/Han/64M-10         21.42m ± 1%   13.42m ± 2%  -37.34% (p=0.000 n=10)
geomean                             3.983µ        2.305µ       -42.14%

                                 │ base.10.txt  │               new.10.txt               │
                                 │     B/s      │      B/s       vs base                 │
IndexRune/10-10                    974.8Mi ± 0%   1126.1Mi ± 0%   +15.52% (p=0.000 n=10)
IndexRune/32-10                    2.556Gi ± 0%    3.517Gi ± 0%   +37.62% (p=0.000 n=10)
IndexRune/4K-10                    45.43Gi ± 0%    47.05Gi ± 0%    +3.56% (p=0.000 n=10)
IndexRune/4M-10                    61.12Gi ± 0%    60.41Gi ± 0%    -1.16% (p=0.000 n=10)
IndexRune/64M-10                   55.74Gi ± 1%    55.57Gi ± 1%         ~ (p=0.218 n=10)
IndexRuneUnicode/Latin/10-10       942.0Mi ± 0%   1297.9Mi ± 0%   +37.78% (p=0.000 n=10)
IndexRuneUnicode/Latin/32-10       2.606Gi ± 0%    4.055Gi ± 0%   +55.61% (p=0.000 n=10)
IndexRuneUnicode/Latin/4K-10       4.322Gi ± 0%   11.392Gi ± 1%  +163.57% (p=0.000 n=10)
IndexRuneUnicode/Latin/4M-10       3.998Gi ± 0%   10.532Gi ± 1%  +163.47% (p=0.000 n=10)
IndexRuneUnicode/Latin/64M-10      3.994Gi ± 1%   10.369Gi ± 1%  +159.61% (p=0.000 n=10)
IndexRuneUnicode/Cyrillic/10-10    947.2Mi ± 0%   1096.1Mi ± 0%   +15.72% (p=0.000 n=10)
IndexRuneUnicode/Cyrillic/32-10    1.565Gi ± 0%    3.424Gi ± 1%  +118.80% (p=0.000 n=10)
IndexRuneUnicode/Cyrillic/4K-10    1.396Gi ± 0%    3.649Gi ± 1%  +161.43% (p=0.000 n=10)
IndexRuneUnicode/Cyrillic/4M-10    1.462Gi ± 0%    3.418Gi ± 1%  +133.76% (p=0.000 n=10)
IndexRuneUnicode/Cyrillic/64M-10   1.450Gi ± 1%    3.422Gi ± 1%  +136.08% (p=0.000 n=10)
IndexRuneUnicode/Han/10-10         944.6Mi ± 0%    881.7Mi ± 1%    -6.66% (p=0.000 n=10)
IndexRuneUnicode/Han/32-10         797.0Mi ± 1%   2809.3Mi ± 1%  +252.47% (p=0.000 n=10)
IndexRuneUnicode/Han/4K-10         2.707Gi ± 0%    7.798Gi ± 1%  +188.04% (p=0.000 n=10)
IndexRuneUnicode/Han/4M-10         2.919Gi ± 0%    4.757Gi ± 2%   +63.01% (p=0.000 n=10)
IndexRuneUnicode/Han/64M-10        2.917Gi ± 1%    4.656Gi ± 2%   +59.60% (p=0.000 n=10)
geomean                            3.036Gi         5.246Gi        +72.82%

goos: linux
goarch: amd64
pkg: bytes
                                │   old.txt    │                new.txt                │
                                │    sec/op    │    sec/op      vs base                │
IndexRune/10-4                    10.805n ± 0%    6.999n ±  0%  -35.22% (p=0.000 n=10)
IndexRune/32-4                    12.515n ± 0%    7.539n ±  0%  -39.76% (p=0.000 n=10)
IndexRune/4K-4                     71.69n ± 0%    68.39n ±  0%   -4.60% (p=0.000 n=10)
IndexRune/4M-4                    125.19µ ± 2%    63.05µ ±  0%  -49.63% (p=0.000 n=10)
IndexRune/64M-4                    1.050m ± 1%    1.053m ±  0%        ~ (p=0.353 n=10)
IndexRuneUnicode/Latin/10-4        9.471n ± 0%    6.144n ±  1%  -35.13% (p=0.000 n=10)
IndexRuneUnicode/Latin/32-4       12.540n ± 0%    6.655n ±  0%  -46.93% (p=0.000 n=10)
IndexRuneUnicode/Latin/4K-4        522.1n ± 0%    207.2n ±  0%  -60.32% (p=0.000 n=10)
IndexRuneUnicode/Latin/4M-4        626.1µ ± 0%    297.2µ ±  0%  -52.54% (p=0.000 n=10)
IndexRuneUnicode/Latin/64M-4      13.866m ± 3%    5.069m ±  4%  -63.44% (p=0.000 n=10)
IndexRuneUnicode/Cyrillic/10-4    10.920n ± 0%    7.213n ±  0%  -33.95% (p=0.000 n=10)
IndexRuneUnicode/Cyrillic/32-4    12.515n ± 0%    7.780n ±  0%  -37.83% (p=0.000 n=10)
IndexRuneUnicode/Cyrillic/4K-4    2650.0n ± 0%    621.5n ±  0%  -76.55% (p=0.000 n=10)
IndexRuneUnicode/Cyrillic/4M-4    2744.7µ ± 0%    723.2µ ±  0%  -73.65% (p=0.000 n=10)
IndexRuneUnicode/Cyrillic/64M-4    44.18m ± 0%    14.22m ± 14%  -67.82% (p=0.000 n=10)
IndexRuneUnicode/Han/10-4         10.795n ± 0%    9.734n ±  1%   -9.83% (p=0.000 n=10)
IndexRuneUnicode/Han/32-4          12.79n ± 0%    10.42n ±  1%  -18.46% (p=0.000 n=10)
IndexRuneUnicode/Han/4K-4          519.7n ± 0%    288.4n ±  0%  -44.51% (p=0.000 n=10)
IndexRuneUnicode/Han/4M-4          498.2µ ± 0%    443.0µ ±  0%  -11.07% (p=0.000 n=10)
IndexRuneUnicode/Han/64M-4         9.654m ± 2%   12.223m ±  1%  +26.61% (p=0.000 n=10)
geomean                            3.168µ         1.828µ        -42.30%

                                │    old.txt    │                 new.txt                 │
                                │      B/s      │      B/s        vs base                 │
IndexRune/10-4                     882.5Mi ± 0%   1362.6Mi ±  0%   +54.41% (p=0.000 n=10)
IndexRune/32-4                     2.381Gi ± 0%    3.953Gi ±  0%   +66.00% (p=0.000 n=10)
IndexRune/4K-4                     53.21Gi ± 0%    55.77Gi ±  0%    +4.82% (p=0.000 n=10)
IndexRune/4M-4                     31.20Gi ± 2%    61.95Gi ±  0%   +98.55% (p=0.000 n=10)
IndexRune/64M-4                    59.54Gi ± 1%    59.37Gi ±  0%         ~ (p=0.353 n=10)
IndexRuneUnicode/Latin/10-4       1006.9Mi ± 0%   1552.3Mi ±  1%   +54.17% (p=0.000 n=10)
IndexRuneUnicode/Latin/32-4        2.376Gi ± 0%    4.478Gi ±  0%   +88.45% (p=0.000 n=10)
IndexRuneUnicode/Latin/4K-4        7.306Gi ± 0%   18.411Gi ±  0%  +152.01% (p=0.000 n=10)
IndexRuneUnicode/Latin/4M-4        6.239Gi ± 0%   13.145Gi ±  0%  +110.70% (p=0.000 n=10)
IndexRuneUnicode/Latin/64M-4       4.507Gi ± 3%   12.329Gi ±  4%  +173.54% (p=0.000 n=10)
IndexRuneUnicode/Cyrillic/10-4     873.0Mi ± 0%   1322.2Mi ±  0%   +51.46% (p=0.000 n=10)
IndexRuneUnicode/Cyrillic/32-4     2.382Gi ± 0%    3.831Gi ±  0%   +60.84% (p=0.000 n=10)
IndexRuneUnicode/Cyrillic/4K-4     1.439Gi ± 0%    6.138Gi ±  0%  +326.43% (p=0.000 n=10)
IndexRuneUnicode/Cyrillic/4M-4     1.423Gi ± 0%    5.401Gi ±  0%  +279.52% (p=0.000 n=10)
IndexRuneUnicode/Cyrillic/64M-4    1.415Gi ± 0%    4.396Gi ± 17%  +210.79% (p=0.000 n=10)
IndexRuneUnicode/Han/10-4          883.4Mi ± 0%    979.7Mi ±  1%   +10.90% (p=0.000 n=10)
IndexRuneUnicode/Han/32-4          2.331Gi ± 0%    2.858Gi ±  1%   +22.61% (p=0.000 n=10)
IndexRuneUnicode/Han/4K-4          7.340Gi ± 0%   13.226Gi ±  0%   +80.19% (p=0.000 n=10)
IndexRuneUnicode/Han/4M-4          7.841Gi ± 0%    8.817Gi ±  0%   +12.44% (p=0.000 n=10)
IndexRuneUnicode/Han/64M-4         6.474Gi ± 2%    5.113Gi ±  1%   -21.02% (p=0.000 n=10)
geomean                            3.816Gi         6.614Gi         +73.32%

strings package benchmarks:

goos: darwin
goarch: arm64
pkg: strings
                       │ base.index_rune.10.txt │        new.index_rune.10.txt        │
                       │         sec/op         │   sec/op     vs base                │
IndexRune-10                       11.905n ± 5%   6.633n ± 6%  -44.28% (p=0.000 n=10)
IndexRuneLongString-10             13.800n ± 1%   7.330n ± 2%  -46.88% (p=0.000 n=10)
IndexRuneFastPath-10                3.477n ± 0%   3.481n ± 1%        ~ (p=0.468 n=10)
geomean                             8.297n        5.531n       -33.34%

Change-Id: I59357fda1c8ac85315b759930f620dbce1ba4721
Reviewed-on: https://go-review.googlesource.com/c/go/+/539116
Reviewed-by: Ian Lance Taylor <iant@google.com>
Reviewed-by: Carlos Amedee <carlos@golang.org>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Auto-Submit: Ian Lance Taylor <iant@google.com>
2024-08-14 18:25:29 +00:00
aimuz 9becf401de bytes, strings: add Lines, SplitSeq, SplitAfterSeq, FieldsSeq, FieldsFuncSeq
Fixes #61901.

Change-Id: I4db21c91fd21079f2aa3bc81fb03dd6f40423a38
GitHub-Last-Rev: ed3df560a4
GitHub-Pull-Request: golang/go#67543
Reviewed-on: https://go-review.googlesource.com/c/go/+/587095
Auto-Submit: Ian Lance Taylor <iant@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Carlos Amedee <carlos@golang.org>
Reviewed-by: Ian Lance Taylor <iant@google.com>
2024-08-14 18:23:13 +00:00
Oleksandr Redko 5a81570bf2 bytes,strings: use a more universal Cyrillic word
The word "брат" (brother) is the same across Slavic languages that
use the Cyrillic script, such as Bulgarian, Macedonian, Russian,
Ukrainian, and others.

Change-Id: I5155e6bb16a02dec5d93a01b79f9570f43f09444
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2024-08-07 17:22:36 +00:00
aimuz 677e080dfe bytes, strings: replace reflect.DeepEqual and custom eq with slices.Equal in tests
Change-Id: I016672af79d49a00ddc2d0449cdaac61e98b4ba0
GitHub-Last-Rev: 38d15d9a03
GitHub-Pull-Request: golang/go#68730
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2024-08-05 18:44:21 +00:00
Jes Cok 67c3f012cf bytes,slices,strings: optimize Repeat a bit
Like slices.Repeat, use math/bits.Mul to detect overflow in order to
avoid a divide which is slow.

While here, also use builtin min/max to simplify code.

Change-Id: I4a6d8cd5df97fa75f4e324d4be1405ce53c03d31
GitHub-Last-Rev: 54ba5c7126
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2024-08-01 21:32:50 +00:00
apocelipes c0eac35a4c bytes,strings,unicode/utf16: use slices to clean up tests
Replace reflect.DeepEqual with slices.Equal, which is much faster.
Remove some redundant helper functions.

Change-Id: I51b32a3d0c3fc5ad0d3b6ff0dd03f39c507e5762
GitHub-Last-Rev: e21f46d4a0
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2024-07-24 18:45:08 +00:00
Zxilly 90c6558b6a internal/bytealg: extend memchr result correctly on wasm
The mem address should be regarded as uint32.

Fixes #65571

Change-Id: Icee38d11f2d93eeca7d50b2e133159e321daeb90
GitHub-Last-Rev: c2568b1043
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2024-07-17 07:00:20 +00:00
Kir Kolyshkin 9915b87059 bytes: more cross-references in docstrings
Change-Id: Iea0243edcf8bf73ce325695178a3ea5cfe420d31
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2024-07-16 18:17:37 +00:00
Kir Kolyshkin 451a284d80 strings,bytes,regexp: use lists in Split* docstrings
This looks better than the default of using a code block.
While at it, fix punctuation.

Change-Id: I86abca4da1e9999b7e9043e615ad0988d35a5a46
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2024-07-16 18:17:26 +00:00
Russ Cox 2a7ca156b8 all: document legacy //go:linkname for final round of modules
Add linknames for most modules with ≥50 dependents.
Add linknames for a few other modules that we know
are important but are below 50.

Remove linknames from badlinkname.go that do not merit
inclusion (very small number of dependents).
We can add them back later if the need arises.

Fixes #67401. (For now.)

Change-Id: I1e49fec0292265256044d64b1841d366c4106002
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2024-05-29 17:58:53 +00:00
Ian Lance Taylor b0b1d42db3 all: change from sort functions to slices functions where feasible
Doing this because the slices functions are slightly faster and
slightly easier to use. It also removes one dependency layer.

This CL does not change packages that are used during bootstrap,
as the bootstrap compiler does not have the required slices functions.
It does not change the go/scanner package because the ErrorList
Len, Swap, and Less methods are part of the Go 1 API.

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2024-05-23 01:00:11 +00:00
go101 44b54b99c9 strings,bytes: improve Repeat panic messages
The Repeat("-", maxInt) call should produce

   panic: runtime error: makeslice: len out of range

instead of

   panic: strings: Repeat output length overflow

This PR is only for theory perfection.

Change-Id: If67d87b147d666fbbb7238656f2a0cb6cf1dbb5b
GitHub-Last-Rev: 29dc0cb9c9
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2024-05-03 12:58:37 +00:00
Daniel Martí 959e65c41c bytes: fix up godoc link errors
[Reader.Reader] does not exist in this package.
These docs most likely meant to refer to [Reader] itself.

Change-Id: I4fa117e8541573e0be7c13751fdfc102d5f2d604
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2024-04-30 19:45:36 +00:00
qmuntal 5ff0b53174 bytes: skip TestNewBufferShallow if optimization is disabled
TestNewBufferShallow should be skipped if optimization is disabled.

It is currently failing on no-opt builders.

Change-Id: Ib5e62022a56a4e5f158f247d69a6229d2cb4d99e
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2024-04-26 13:31:36 +00:00
Joe Tsai 62dfa43101 bytes: add test to ensure shallow copy of NewBuffer does not allocate
At present, there is no API to reset the underlying []byte
of an existing Buffer struct, except to shallow copy
the entire Buffer struct.

Updates #67004

Change-Id: I08998f7a95ae5bde0897d86247d47f23cd784583
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2024-04-24 13:36:51 +00:00
cui fliter a5f8ae9f65 bytes: add a colon after Output to make the Example in the document display correctly
The document address currently showing the problem is: https://pkg.go.dev/bytes#Buffer.ReadByte

Change-Id: Ib52747e38f72541f3ca2a595aa8eca5d91281c80
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2024-03-04 15:54:40 +00:00
Mateusz Poliwczak 968b71bce4 strings: make use of sizeclasses in (*Builder).Grow
Fixes #64833

Change-Id: Ice3f5dfab65f5525bc7a6f57ddeaabda8d64dfa3
GitHub-Last-Rev: 38f1d6c19d
GitHub-Pull-Request: golang/go#64835
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2024-02-19 19:51:15 +00:00
Mauri de Souza Meneguzzo 66b776b025 runtime: short path for equal pointers in arm64 memequal
If memequal is invoked with the same pointers as arguments it ends up
comparing the whole memory contents, instead of just comparing the pointers.

This effectively makes an operation that could be O(1) into O(n). All the
other architectures already have this optimization in place. For
instance, arm64 also have it, in memequal_varlen.

Such optimization is very specific, one case that it will probably benefit is
programs that rely heavily on interning of strings.

goos: darwin
goarch: arm64
pkg: bytes
                 │      old.txt       │               new.txt                │
                 │       sec/op       │    sec/op     vs base                │
Equal/same/1-8           2.678n ± ∞ ¹   2.400n ± ∞ ¹   -10.38% (p=0.008 n=5)
Equal/same/6-8           3.267n ± ∞ ¹   2.431n ± ∞ ¹   -25.59% (p=0.008 n=5)
Equal/same/9-8           2.981n ± ∞ ¹   2.385n ± ∞ ¹   -19.99% (p=0.008 n=5)
Equal/same/15-8          2.974n ± ∞ ¹   2.390n ± ∞ ¹   -19.64% (p=0.008 n=5)
Equal/same/16-8          2.983n ± ∞ ¹   2.380n ± ∞ ¹   -20.21% (p=0.008 n=5)
Equal/same/20-8          3.567n ± ∞ ¹   2.384n ± ∞ ¹   -33.17% (p=0.008 n=5)
Equal/same/32-8          3.568n ± ∞ ¹   2.385n ± ∞ ¹   -33.16% (p=0.008 n=5)
Equal/same/4K-8         78.040n ± ∞ ¹   2.378n ± ∞ ¹   -96.95% (p=0.008 n=5)
Equal/same/4M-8      78713.000n ± ∞ ¹   2.385n ± ∞ ¹  -100.00% (p=0.008 n=5)
Equal/same/64M-8   1348095.000n ± ∞ ¹   2.381n ± ∞ ¹  -100.00% (p=0.008 n=5)
geomean                  43.52n         2.390n         -94.51%
¹ need >= 6 samples for confidence interval at level 0.95

                 │    old.txt    │                     new.txt                      │
                 │      B/s      │         B/s          vs base                     │
Equal/same/1-8     356.1Mi ± ∞ ¹         397.3Mi ± ∞ ¹        +11.57% (p=0.008 n=5)
Equal/same/6-8     1.711Gi ± ∞ ¹         2.298Gi ± ∞ ¹        +34.35% (p=0.008 n=5)
Equal/same/9-8     2.812Gi ± ∞ ¹         3.515Gi ± ∞ ¹        +24.99% (p=0.008 n=5)
Equal/same/15-8    4.698Gi ± ∞ ¹         5.844Gi ± ∞ ¹        +24.41% (p=0.008 n=5)
Equal/same/16-8    4.995Gi ± ∞ ¹         6.260Gi ± ∞ ¹        +25.34% (p=0.008 n=5)
Equal/same/20-8    5.222Gi ± ∞ ¹         7.814Gi ± ∞ ¹        +49.63% (p=0.008 n=5)
Equal/same/32-8    8.353Gi ± ∞ ¹        12.496Gi ± ∞ ¹        +49.59% (p=0.008 n=5)
Equal/same/4K-8    48.88Gi ± ∞ ¹       1603.96Gi ± ∞ ¹      +3181.17% (p=0.008 n=5)
Equal/same/4M-8    49.63Gi ± ∞ ¹    1637911.85Gi ± ∞ ¹   +3300381.91% (p=0.008 n=5)
Equal/same/64M-8   46.36Gi ± ∞ ¹   26253069.97Gi ± ∞ ¹  +56626517.99% (p=0.008 n=5)
geomean            6.737Gi               122.7Gi            +1721.01%
¹ need >= 6 samples for confidence interval at level 0.95

Fixes #64381

Change-Id: I7d423930a688edd88c4ba60d45e097296d9be852
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2024-01-24 16:07:25 +00:00
Keith Randall 446a5dcf5a bytes: add a boundary test for Count of 1 byte
This bottoms out in internal/bytealg.Count, which does a fair amount
of avx shenanigans. Make sure we're not reading out of bounds.

Change-Id: Ied0e461f536f75acc24c6797f7fc74e3f3901c10
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2023-11-30 20:05:58 +00:00
Jes Cok a05a25cb19 bytes,internal/bytealg: add func bytealg.LastIndexRabinKarp
Also rename 'substr' to 'sep' in IndexRabinKarp for consistency.

Change-Id: Icc2ad1116aecaf002c8264daa2fa608306c9a88a
GitHub-Last-Rev: 1784b93f53
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2023-11-01 19:02:57 +00:00
Jes Cok 68e52bc03c bytes,internal/bytealg: eliminate IndexRabinKarpBytes using generics
This is a follow-up to CL 538175.

Change-Id: Iec2523b36a16d7e157c17858c89fcd43c2470d58
GitHub-Last-Rev: 812d36e57c
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2023-10-31 17:14:04 +00:00
Jes Cok b46aec0765 bytes,internal/bytealg: eliminate HashStrBytes,HashStrRevBytes using …
…generics

The logic of HashStrBytes, HashStrRevBytes and HashStr, HashStrRev,
are exactly the same, except that the types are different.

Since the bootstrap toolchain is bumped to 1.20, we can eliminate them
by using generics.

Change-Id: I4336b1cab494ba963f09646c169b45f6b1ee62e3
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2023-10-27 15:55:16 +00:00
cui fliter 6dd7462a04 bytes,strings: add available godoc link
Change-Id: Id9706a783d3321e3706eeee102286522e7968efd
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2023-10-13 17:10:31 +00:00
cui fliter 8f61fab618 bytes,strings: add example for ContainsFunc
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2023-10-09 22:05:38 +00:00
Matthew Dempsky 62fb281cf7 bytes, strings: use "reports whether" in HasPrefix and HasSuffix
Update the doc comments to use the more idiomatic and common phrase
"reports whether" instead of "tests whether".

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2023-09-01 04:29:02 +00:00
Tobias Klauser 890a62bf1b internal/bytealg: add generic LastIndexByte{,String}
To avoid duplicating them in net/netip and os and to allow these
packages automatically benefiting from future performance improvements
when optimized native LastIndexByte{,String} implementations are added.

For #36891

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2023-08-25 15:08:28 +00:00
cui fliter 0163b3b32c all: remove redundant string conversions when formatting []byte with %s
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2023-08-22 22:52:37 +00:00
Johan Brandhorst-Satzkorn 089e37a931 bytes: remove builders check from compare test
TestCompareBytes already took into account the -short
testing flag, however, only if not run on one of the Go builders.
This extra condition is no longer necessary as we have much
better longtest coverage than we did when the check was added.

Fixes #61071

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2023-07-13 23:11:42 +00:00
Mark Ryan 03cd8a7b0e internal/bytealg: fix alignment code in equal_riscv64.s
The riscv64 implementation of equal has an optimization that is
applied when both pointers share the same alignment but that alignment
is not 8 bytes.  In this case it tries to align both pointers to an 8 byte boundaries,
by individually comparing the first few bytes of each buffer.  Unfortunately,
the existing code is incorrect.  It adjusts the pointers by the wrong number
of bytes resulting, in most cases, in pointers that are not 8 byte aligned.

This commit fixes the issue by individually comparing the first
(8 - (pointer & 7)) bytes of each buffer rather than the first
(pointer & 7) bytes.

This particular optimization is not covered by any of the existing
benchmarks so a new benchmark, BenchmarkEqualBothUnaligned,
is provided.  The benchmark tests the case where both pointers have
the same alignment but may not be 8 byte aligned.  Results of the
new benchmark along with some of the existing benchmarks generated on
a SiFive HiFive Unmatched A00 with 16GB of RAM running Ubuntu 23.04
are presented below.

Equal/0-4                                 3.356n ± 0%    3.357n ± 0%        ~ (p=0.840 n=10)
Equal/1-4                                 63.91n ± 7%    65.97n ± 5%   +3.22% (p=0.029 n=10)
Equal/6-4                                 72.94n ± 5%    76.09n ± 4%        ~ (p=0.075 n=10)
Equal/9-4                                 84.61n ± 7%    85.83n ± 3%        ~ (p=0.315 n=10)
Equal/15-4                                103.7n ± 2%    102.9n ± 4%        ~ (p=0.739 n=10)
Equal/16-4                                89.14n ± 3%   100.40n ± 4%  +12.64% (p=0.000 n=10)
Equal/20-4                                107.8n ± 3%    106.8n ± 3%        ~ (p=0.725 n=10)
Equal/32-4                                63.95n ± 8%    67.79n ± 7%        ~ (p=0.089 n=10)
Equal/4K-4                                1.256µ ± 1%    1.254µ ± 0%        ~ (p=0.925 n=10)
Equal/4M-4                                1.231m ± 0%    1.230m ± 0%   -0.04% (p=0.011 n=10)
Equal/64M-4                               19.77m ± 0%    19.78m ± 0%        ~ (p=0.052 n=10)
EqualBothUnaligned/64_0-4                 43.70n ± 4%    44.40n ± 5%        ~ (p=0.529 n=10)
EqualBothUnaligned/64_1-4                6957.5n ± 0%    105.9n ± 1%  -98.48% (p=0.000 n=10)
EqualBothUnaligned/64_4-4                 100.1n ± 2%    101.5n ± 4%        ~ (p=0.149 n=10)
EqualBothUnaligned/64_7-4               6965.00n ± 0%    95.60n ± 4%  -98.63% (p=0.000 n=10)
EqualBothUnaligned/4096_0-4               1.233µ ± 1%    1.225µ ± 0%   -0.65% (p=0.015 n=10)
EqualBothUnaligned/4096_1-4             584.226µ ± 0%    1.277µ ± 0%  -99.78% (p=0.000 n=10)
EqualBothUnaligned/4096_4-4               1.270µ ± 1%    1.268µ ± 0%        ~ (p=0.105 n=10)
EqualBothUnaligned/4096_7-4             584.944µ ± 0%    1.266µ ± 1%  -99.78% (p=0.000 n=10)
EqualBothUnaligned/4194304_0-4            1.241m ± 0%    1.236m ± 0%   -0.38% (p=0.035 n=10)
EqualBothUnaligned/4194304_1-4          600.956m ± 0%    1.238m ± 0%  -99.79% (p=0.000 n=10)
EqualBothUnaligned/4194304_4-4            1.239m ± 0%    1.241m ± 0%   +0.22% (p=0.007 n=10)
EqualBothUnaligned/4194304_7-4          601.036m ± 0%    1.239m ± 0%  -99.79% (p=0.000 n=10)
EqualBothUnaligned/67108864_0-4           19.79m ± 0%    19.78m ± 0%        ~ (p=0.393 n=10)
EqualBothUnaligned/67108864_1-4         9616.61m ± 0%    19.82m ± 0%  -99.79% (p=0.000 n=10)
EqualBothUnaligned/67108864_4-4           19.82m ± 0%    19.82m ± 0%        ~ (p=0.971 n=10)
EqualBothUnaligned/67108864_7-4         9616.34m ± 0%    19.86m ± 0%  -99.79% (p=0.000 n=10)
geomean                                   38.38µ         7.194µ       -81.26%

Change-Id: I4caab6c3450bd7e2773426b08b70bbc37fbe4e5f
Reviewed-on: https://go-review.googlesource.com/c/go/+/500855
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: Keith Randall <khr@google.com>
Run-TryBot: Keith Randall <khr@golang.org>
Reviewed-by: Cherry Mui <cherryyz@google.com>
2023-06-29 02:34:59 +00:00
Mark Ryan bfa25c3f6c internal/bytealg: fix alignment code in compare_riscv64.s
The riscv64 implementation of compare has an optimization that is
applied when both pointers share the same alignment but that alignment
is not 8 bytes.  In this case it tries to align both pointers to an 8 byte boundaries,
by individually comparing the first few bytes of each buffer.  Unfortunately,
the existing code is incorrect.  It adjusts the pointers by the wrong number
of bytes resulting, in most cases, in pointers that are not 8 byte aligned.

This commit fixes the issue by individually comparing the first
(8 - (pointer & 7)) bytes of each buffer rather than the first
(pointer & 7) bytes.

We also remove an unnecessary immediate MOV instruction.

This particular optimization is not covered by any of the existing
benchmarks so a new benchmark, benchmarkCompareBytesBigBothUnaligned,
is provided.  The benchmark tests the case where both pointers have
the same alignment but may not be 8 byte aligned.  Results of the
new benchmark along with some of the existing benchmarks generated on
a SiFive HiFive Unmatched A00 with 16GB of RAM running Ubuntu 23.04
are presented below.

CompareBytesEqual-4                           70.00n ±  6%   68.32n ±  0%   -2.40% (p=0.020 n=10)
CompareBytesToNil-4                           19.31n ±  0%   18.47n ±  0%   -4.35% (p=0.000 n=10)
CompareBytesEmpty-4                           16.79n ±  0%   15.95n ±  0%   -4.97% (p=0.000 n=10)
CompareBytesIdentical-4                       19.94n ± 15%   18.32n ± 13%   -8.15% (p=0.040 n=10)
CompareBytesSameLength-4                      37.93n ±  0%   42.44n ±  1%  +11.91% (p=0.000 n=10)
CompareBytesDifferentLength-4                 37.93n ±  0%   42.44n ±  0%  +11.89% (p=0.000 n=10)
CompareBytesBigUnaligned/offset=1-4           3.881m ± 14%   3.880m ± 15%        ~ (p=0.436 n=10)
CompareBytesBigUnaligned/offset=2-4           3.884m ±  0%   3.875m ±  0%        ~ (p=0.190 n=10)
CompareBytesBigUnaligned/offset=3-4           3.858m ±  1%   3.868m ±  1%        ~ (p=0.105 n=10)
CompareBytesBigUnaligned/offset=4-4           3.877m ±  1%   3.876m ±  0%        ~ (p=0.529 n=10)
CompareBytesBigUnaligned/offset=5-4           3.859m ±  0%   3.874m ±  0%   +0.39% (p=0.009 n=10)
CompareBytesBigUnaligned/offset=6-4           3.878m ±  1%   3.876m ±  0%        ~ (p=0.353 n=10)
CompareBytesBigUnaligned/offset=7-4           3.868m ±  1%   3.877m ±  0%        ~ (p=0.190 n=10)
CompareBytesBigBothUnaligned/offset=0-4       1.586m ±  0%   1.765m ±  0%  +11.30% (p=0.000 n=10)
CompareBytesBigBothUnaligned/offset=1-4     153.132m ±  1%   1.765m ±  1%  -98.85% (p=0.000 n=10)
CompareBytesBigBothUnaligned/offset=2-4     152.930m ±  1%   1.765m ±  1%  -98.85% (p=0.000 n=10)
CompareBytesBigBothUnaligned/offset=3-4     152.093m ±  1%   1.769m ±  0%  -98.84% (p=0.000 n=10)
CompareBytesBigBothUnaligned/offset=4-4       1.602m ±  0%   1.764m ±  0%  +10.11% (p=0.000 n=10)
CompareBytesBigBothUnaligned/offset=5-4     152.314m ±  1%   1.768m ±  0%  -98.84% (p=0.000 n=10)
CompareBytesBigBothUnaligned/offset=6-4     152.905m ±  1%   1.764m ±  1%  -98.85% (p=0.000 n=10)
CompareBytesBigBothUnaligned/offset=7-4     152.951m ±  1%   1.804m ±  2%  -98.82% (p=0.000 n=10)
CompareBytesBig-4                             1.441m ± 21%   1.373m ± 55%        ~ (p=0.481 n=10)
CompareBytesBigIdentical-4                    19.94n ±  1%   19.10n ±  0%   -4.21% (p=0.001 n=10)
geomean                                       243.7µ         76.65µ        -68.54%

CompareBytesBigUnaligned/offset=1-4          257.7Mi ± 12%     257.7Mi ± 13%          ~ (p=0.424 n=10)
CompareBytesBigUnaligned/offset=2-4          257.5Mi ±  0%     258.1Mi ±  0%          ~ (p=0.190 n=10)
CompareBytesBigUnaligned/offset=3-4          259.2Mi ±  1%     258.5Mi ±  1%          ~ (p=0.105 n=10)
CompareBytesBigUnaligned/offset=4-4          257.9Mi ±  1%     258.0Mi ±  0%          ~ (p=0.529 n=10)
CompareBytesBigUnaligned/offset=5-4          259.1Mi ±  0%     258.1Mi ±  0%     -0.39% (p=0.008 n=10)
CompareBytesBigUnaligned/offset=6-4          257.9Mi ±  1%     258.0Mi ±  0%          ~ (p=0.353 n=10)
CompareBytesBigUnaligned/offset=7-4          258.5Mi ±  1%     257.9Mi ±  0%          ~ (p=0.190 n=10)
CompareBytesBigBothUnaligned/offset=0-4      630.6Mi ±  0%     566.6Mi ±  0%    -10.15% (p=0.000 n=10)
CompareBytesBigBothUnaligned/offset=1-4      6.533Mi ±  1%   566.545Mi ±  1%  +8572.48% (p=0.000 n=10)
CompareBytesBigBothUnaligned/offset=2-4      6.537Mi ±  1%   566.683Mi ±  1%  +8568.27% (p=0.000 n=10)
CompareBytesBigBothUnaligned/offset=3-4      6.576Mi ±  1%   565.200Mi ±  0%  +8495.43% (p=0.000 n=10)
CompareBytesBigBothUnaligned/offset=4-4      624.2Mi ±  0%     566.9Mi ±  0%     -9.18% (p=0.000 n=10)
CompareBytesBigBothUnaligned/offset=5-4      6.566Mi ±  1%   565.758Mi ±  0%  +8516.41% (p=0.000 n=10)
CompareBytesBigBothUnaligned/offset=6-4      6.542Mi ±  1%   567.036Mi ±  1%  +8567.35% (p=0.000 n=10)
CompareBytesBigBothUnaligned/offset=7-4      6.542Mi ±  1%   554.390Mi ±  2%  +8374.05% (p=0.000 n=10)
CompareBytesBig-4                            694.2Mi ± 18%     728.1Mi ± 35%          ~ (p=0.481 n=10)
CompareBytesBigIdentical-4                   47.83Ti ±  1%     49.92Ti ±  0%     +4.39% (p=0.002 n=10)
geomean                                      170.0Mi           813.8Mi         +378.66%

Change-Id: I0a2d0386d5ca1ffa249682a12ebd1533508e31e9
Reviewed-on: https://go-review.googlesource.com/c/go/+/497838
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Reviewed-by: Joel Sing <joel@sing.id.au>
Reviewed-by: Keith Randall <khr@golang.org>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: M Zhuo <mzh@golangcn.org>
Reviewed-by: Keith Randall <khr@google.com>
Run-TryBot: M Zhuo <mzh@golangcn.org>
2023-05-30 16:05:30 +00:00
Alan Donovan 9d35ebba06 std: fix various nilness findings
Found by running
$ go run golang.org/x/tools/go/analysis/passes/nilness/cmd/nilness@latest std

No actual bugs--other than one panic(nil)--but a
few places where error nilness was unclear.

Change-Id: Ia916ba30f46f29c1bcf928cc62280169b922463a
Reviewed-on: https://go-review.googlesource.com/c/go/+/486675
Reviewed-by: Ian Lance Taylor <iant@google.com>
Run-TryBot: Alan Donovan <adonovan@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Auto-Submit: Alan Donovan <adonovan@google.com>
2023-04-20 01:07:29 +00:00
cui fliter d8d22664c6 all: fix misuses of "a" vs "an"
Fixes the misuse of "a" vs "an", according to English grammatical
expectations and using https://www.a-or-an.com/

Change-Id: I53ac724070e3ff3d33c304483fe72c023c7cda47
Reviewed-on: https://go-review.googlesource.com/c/go/+/480536
Run-TryBot: shuang cui <imcusg@gmail.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Auto-Submit: Ian Lance Taylor <iant@google.com>
Run-TryBot: Ian Lance Taylor <iant@google.com>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
2023-04-04 14:20:53 +00:00
Daniel Martí 9768f736ea all: add a few links in package godocs
I noticed the one in path/filepath while reading the docs,
and the other ones were found via some quick grepping.

Change-Id: I386f2f74ef816a6d18aa2f58ee6b64dbd0147c9e
Reviewed-on: https://go-review.googlesource.com/c/go/+/478795
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
Reviewed-by: Heschi Kreinick <heschi@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@google.com>
2023-03-25 10:16:23 +00:00
Joe Tsai e671fe0c3e bytes: add Buffer.Available and Buffer.AvailableBuffer
This adds a new Buffer.AvailableBuffer method that returns
an empty buffer with a possibly non-empty capacity for use
with append-like APIs.

The typical usage pattern is something like:

	b := bb.AvailableBuffer()
	b = appendValue(b, v)
	bb.Write(b)

It allows logic combining append-like APIs with Buffer
to avoid needing to allocate and manage buffers themselves and
allows the append-like APIs to directly write into the Buffer.

The Buffer.Write method uses the builtin copy function,
which avoids copying bytes if the source and destination are identical.
Thus, Buffer.Write is a constant-time call for this pattern.

Performance:

	BenchmarkBufferAppendNoCopy  2.909 ns/op  5766942167.24 MB/s

This benchmark should only be testing the cost of bookkeeping
and never the copying of the input slice.
Thus, the MB/s should be orders of magnitude faster than RAM.

Fixes #53685

Change-Id: I0b41e54361339df309db8d03527689b123f99085
Reviewed-on: https://go-review.googlesource.com/c/go/+/474635
Run-TryBot: Joseph Tsai <joetsai@digital-static.net>
Reviewed-by: Daniel Martí <mvdan@mvdan.cc>
Reviewed-by: Cherry Mui <cherryyz@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Auto-Submit: Joseph Tsai <joetsai@digital-static.net>
Reviewed-by: Ian Lance Taylor <iant@google.com>
2023-03-13 17:03:14 +00:00
Joe Tsai 132fae93b7 bytes, strings: avoid unnecessary zero initialization
Add bytealg.MakeNoZero that specially allocates a []byte
without zeroing it. It assumes the caller will populate every byte.
From within the bytes and strings packages, we can use
bytealg.MakeNoZero in a way where our logic ensures that
the entire slice is overwritten such that uninitialized bytes
are never leaked to the end user.

We use bytealg.MakeNoZero from within the following functions:

* bytes.Join
* bytes.Repeat
* bytes.ToUpper
* bytes.ToLower
* strings.Builder.Grow

The optimization in strings.Builder transitively benefits the following:

* strings.Join
* strings.Map
* strings.Repeat
* strings.ToUpper
* strings.ToLower
* strings.ToValidUTF8
* strings.Replace
* any user logic that depends on strings.Builder

This optimization is especially notable on large buffers that
do not fit in the CPU cache, such that the cost of
runtime.memclr and runtime.memmove are non-trivial since they are
both limited by the relatively slow speed of physical RAM.

Performance:

	RepeatLarge/256/1             66.0ns ± 3%    64.5ns ± 1%      ~     (p=0.095 n=5+5)
	RepeatLarge/256/16            55.4ns ± 5%    53.1ns ± 3%    -4.17%  (p=0.016 n=5+5)
	RepeatLarge/512/1             95.5ns ± 7%    87.1ns ± 2%    -8.78%  (p=0.008 n=5+5)
	RepeatLarge/512/16            84.4ns ± 9%    76.2ns ± 5%    -9.73%  (p=0.016 n=5+5)
	RepeatLarge/1024/1             161ns ± 4%     144ns ± 7%   -10.45%  (p=0.016 n=5+5)
	RepeatLarge/1024/16            148ns ± 3%     141ns ± 5%      ~     (p=0.095 n=5+5)
	RepeatLarge/2048/1             296ns ± 7%     288ns ± 5%      ~     (p=0.841 n=5+5)
	RepeatLarge/2048/16            298ns ± 8%     281ns ± 5%      ~     (p=0.151 n=5+5)
	RepeatLarge/4096/1             593ns ± 8%     539ns ± 8%    -8.99%  (p=0.032 n=5+5)
	RepeatLarge/4096/16            568ns ±12%     526ns ± 7%      ~     (p=0.056 n=5+5)
	RepeatLarge/8192/1            1.15µs ± 8%    1.08µs ±12%      ~     (p=0.095 n=5+5)
	RepeatLarge/8192/16           1.12µs ± 4%    1.07µs ± 7%      ~     (p=0.310 n=5+5)
	RepeatLarge/8192/4097         1.77ns ± 1%    1.76ns ± 2%      ~     (p=0.310 n=5+5)
	RepeatLarge/16384/1           2.06µs ± 7%    1.94µs ± 5%      ~     (p=0.222 n=5+5)
	RepeatLarge/16384/16          2.02µs ± 4%    1.92µs ± 6%      ~     (p=0.095 n=5+5)
	RepeatLarge/16384/4097        1.50µs ±15%    1.44µs ±11%      ~     (p=0.802 n=5+5)
	RepeatLarge/32768/1           3.90µs ± 8%    3.65µs ±11%      ~     (p=0.151 n=5+5)
	RepeatLarge/32768/16          3.92µs ±14%    3.68µs ±12%      ~     (p=0.222 n=5+5)
	RepeatLarge/32768/4097        3.71µs ± 5%    3.43µs ± 4%    -7.54%  (p=0.032 n=5+5)
	RepeatLarge/65536/1           7.47µs ± 8%    6.88µs ± 9%      ~     (p=0.056 n=5+5)
	RepeatLarge/65536/16          7.29µs ± 4%    6.74µs ± 6%    -7.60%  (p=0.016 n=5+5)
	RepeatLarge/65536/4097        7.90µs ±11%    6.34µs ± 5%   -19.81%  (p=0.008 n=5+5)
	RepeatLarge/131072/1          17.0µs ±18%    14.1µs ± 6%   -17.32%  (p=0.008 n=5+5)
	RepeatLarge/131072/16         15.2µs ± 2%    16.2µs ±17%      ~     (p=0.151 n=5+5)
	RepeatLarge/131072/4097       15.7µs ± 6%    14.8µs ±11%      ~     (p=0.095 n=5+5)
	RepeatLarge/262144/1          30.4µs ± 5%    31.4µs ±13%      ~     (p=0.548 n=5+5)
	RepeatLarge/262144/16         30.1µs ± 4%    30.7µs ±11%      ~     (p=1.000 n=5+5)
	RepeatLarge/262144/4097       31.2µs ± 7%    32.7µs ±13%      ~     (p=0.310 n=5+5)
	RepeatLarge/524288/1          67.5µs ± 9%    63.7µs ± 3%      ~     (p=0.095 n=5+5)
	RepeatLarge/524288/16         67.2µs ± 5%    62.9µs ± 6%      ~     (p=0.151 n=5+5)
	RepeatLarge/524288/4097       65.5µs ± 4%    65.2µs ±18%      ~     (p=0.548 n=5+5)
	RepeatLarge/1048576/1          141µs ± 6%     137µs ±14%      ~     (p=0.421 n=5+5)
	RepeatLarge/1048576/16         140µs ± 2%     134µs ±11%      ~     (p=0.222 n=5+5)
	RepeatLarge/1048576/4097       141µs ± 3%     134µs ±10%      ~     (p=0.151 n=5+5)
	RepeatLarge/2097152/1          258µs ± 2%     271µs ±10%      ~     (p=0.222 n=5+5)
	RepeatLarge/2097152/16         263µs ± 6%     273µs ± 9%      ~     (p=0.151 n=5+5)
	RepeatLarge/2097152/4097       270µs ± 2%     277µs ± 6%      ~     (p=0.690 n=5+5)
	RepeatLarge/4194304/1          684µs ± 3%     467µs ± 6%   -31.69%  (p=0.008 n=5+5)
	RepeatLarge/4194304/16         682µs ± 1%     471µs ± 7%   -30.91%  (p=0.008 n=5+5)
	RepeatLarge/4194304/4097       685µs ± 2%     465µs ±20%   -32.12%  (p=0.008 n=5+5)
	RepeatLarge/8388608/1         1.50ms ± 1%    1.16ms ± 8%   -22.63%  (p=0.008 n=5+5)
	RepeatLarge/8388608/16        1.50ms ± 2%    1.22ms ±17%   -18.49%  (p=0.008 n=5+5)
	RepeatLarge/8388608/4097      1.51ms ± 7%    1.33ms ±11%   -11.56%  (p=0.008 n=5+5)
	RepeatLarge/16777216/1        3.48ms ± 4%    2.66ms ±13%   -23.76%  (p=0.008 n=5+5)
	RepeatLarge/16777216/16       3.37ms ± 3%    2.57ms ±13%   -23.72%  (p=0.008 n=5+5)
	RepeatLarge/16777216/4097     3.38ms ± 9%    2.50ms ±11%   -26.16%  (p=0.008 n=5+5)
	RepeatLarge/33554432/1        7.74ms ± 1%    4.70ms ±19%   -39.31%  (p=0.016 n=4+5)
	RepeatLarge/33554432/16       7.90ms ± 4%    4.78ms ± 9%   -39.50%  (p=0.008 n=5+5)
	RepeatLarge/33554432/4097     7.80ms ± 2%    4.86ms ±11%   -37.60%  (p=0.008 n=5+5)
	RepeatLarge/67108864/1        16.4ms ± 3%     9.7ms ±15%   -41.29%  (p=0.008 n=5+5)
	RepeatLarge/67108864/16       16.5ms ± 1%     9.9ms ±15%   -39.83%  (p=0.008 n=5+5)
	RepeatLarge/67108864/4097     16.5ms ± 1%    11.0ms ±18%   -32.95%  (p=0.008 n=5+5)
	RepeatLarge/134217728/1       35.2ms ±12%    19.2ms ±10%   -45.58%  (p=0.008 n=5+5)
	RepeatLarge/134217728/16      34.6ms ± 6%    19.3ms ± 7%   -44.07%  (p=0.008 n=5+5)
	RepeatLarge/134217728/4097    33.2ms ± 2%    19.3ms ±14%   -41.79%  (p=0.008 n=5+5)
	RepeatLarge/268435456/1       70.9ms ± 2%    36.2ms ± 5%   -48.87%  (p=0.008 n=5+5)
	RepeatLarge/268435456/16      77.4ms ± 7%    36.1ms ± 8%   -53.33%  (p=0.008 n=5+5)
	RepeatLarge/268435456/4097    75.8ms ± 4%    37.0ms ± 4%   -51.15%  (p=0.008 n=5+5)
	RepeatLarge/536870912/1        163ms ±14%      77ms ± 9%   -52.94%  (p=0.008 n=5+5)
	RepeatLarge/536870912/16       156ms ± 4%      76ms ± 6%   -51.42%  (p=0.008 n=5+5)
	RepeatLarge/536870912/4097     151ms ± 2%      76ms ± 6%   -49.64%  (p=0.008 n=5+5)
	RepeatLarge/1073741824/1       293ms ± 5%     149ms ± 8%   -49.18%  (p=0.008 n=5+5)
	RepeatLarge/1073741824/16      308ms ± 9%     150ms ± 8%   -51.19%  (p=0.008 n=5+5)
	RepeatLarge/1073741824/4097    299ms ± 5%     151ms ± 6%   -49.51%  (p=0.008 n=5+5)

Updates #57153

Change-Id: I024553b7e676d6da6408278109ac1fa8def0a802
Reviewed-on: https://go-review.googlesource.com/c/go/+/456336
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>
Run-TryBot: Joseph Tsai <joetsai@digital-static.net>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Daniel Martí <mvdan@mvdan.cc>
2023-02-27 19:11:00 +00:00
hopehook 0b3f58c48e bytes, strings: add ContainsFunc
Fixes #54386.

Change-Id: I78747da337ed6129e4f7426dd0483a644bed82e3
Reviewed-on: https://go-review.googlesource.com/c/go/+/460216
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>
Run-TryBot: hopehook <hopehook@golangcn.org>
Auto-Submit: Ian Lance Taylor <iant@golang.org>
2023-01-24 22:06:45 +00:00
fangguizhen 85b49d7f21 bytes,strings: add some examples
Change-Id: Ic93ad59119f3549c0f13c4f366f71e9d01b88c47
GitHub-Last-Rev: afb5180472
GitHub-Pull-Request: golang/go#57907
Reviewed-on: https://go-review.googlesource.com/c/go/+/462283
TryBot-Result: Gopher Robot <gobot@golang.org>
Run-TryBot: Ian Lance Taylor <iant@google.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Auto-Submit: Ian Lance Taylor <iant@google.com>
2023-01-20 23:21:39 +00:00
fangguizhen e590afcf2c bytes, strings: rename field in CutSuffix tests
Change-Id: I63181f6540fc1bfcfc988a16bf9fafbd3575cfdf
GitHub-Last-Rev: d90528730a
GitHub-Pull-Request: golang/go#57909
Reviewed-on: https://go-review.googlesource.com/c/go/+/462284
Reviewed-by: Ian Lance Taylor <iant@google.com>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Auto-Submit: Ian Lance Taylor <iant@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Run-TryBot: Ian Lance Taylor <iant@google.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
2023-01-20 01:25:45 +00:00
Carlo Alberto Ferraris dcb90152a4 bytes,strings: optimize Repeat
When generating long strings or slices with Repeat we
currently reuse intermediate states as a way to quickly
build exponentially longer results.

This works well as long as the intermediate states fit into
the processor D-cache. If they don't we start thrashing the
D-cache by reading in the whole intermediate state over and
over on each iteration.

Instead, once we reach a large enough intermediate state (that
allows the memcpy operation to perform at peak) we cap the
size of chunk of the state that is used as source for subsequent
appends. This ensures that this smaller source chunk is always
present in the D-cache, and the append operation does not need
to read the state contents from memory.

Currently the cap is set to 8KB, a number derived via
experimentation to yield the highest performance across a
a large range of result sizes. Slightly higher caps also
produced similar results: 8KB was chosen as the smallest one
in this performance plateau with the intention to minimize
D-cache pollution.

For result sizes larger than the fastest cache levels we get
significantly higher performance compared to the current
implementation:
strings:
name                            old speed      new speed      delta
RepeatLarge/256/1-16            1.73GB/s ± 1%  1.73GB/s ± 0%      ~     (p=0.556 n=5+4)
RepeatLarge/256/16-16           2.02GB/s ± 0%  1.95GB/s ± 8%      ~     (p=0.222 n=5+5)
RepeatLarge/512/1-16            2.30GB/s ±13%  2.47GB/s ± 1%      ~     (p=0.548 n=5+5)
RepeatLarge/512/16-16           2.38GB/s ±16%  2.77GB/s ± 1%   +16.27%  (p=0.032 n=5+5)
RepeatLarge/1024/1-16           3.17GB/s ± 1%  3.18GB/s ± 0%      ~     (p=0.730 n=4+5)
RepeatLarge/1024/16-16          3.39GB/s ± 2%  3.38GB/s ± 1%      ~     (p=0.548 n=5+5)
RepeatLarge/2048/1-16           3.32GB/s ± 2%  3.32GB/s ± 2%      ~     (p=1.000 n=5+5)
RepeatLarge/2048/16-16          3.41GB/s ± 4%  3.46GB/s ± 2%      ~     (p=0.310 n=5+5)
RepeatLarge/4096/1-16           3.60GB/s ± 4%  3.67GB/s ± 3%      ~     (p=0.690 n=5+5)
RepeatLarge/4096/16-16          3.74GB/s ± 3%  3.71GB/s ± 5%      ~     (p=0.690 n=5+5)
RepeatLarge/8192/1-16           3.94GB/s ± 4%  4.01GB/s ± 1%      ~     (p=0.222 n=5+5)
RepeatLarge/8192/16-16          3.94GB/s ± 6%  4.05GB/s ± 1%      ~     (p=0.222 n=5+5)
RepeatLarge/8192/4097-16        4.25GB/s ± 6%  4.32GB/s ± 3%      ~     (p=0.690 n=5+5)
RepeatLarge/16384/1-16          4.96GB/s ± 1%  5.02GB/s ± 2%      ~     (p=0.421 n=5+5)
RepeatLarge/16384/16-16         4.99GB/s ± 2%  5.07GB/s ± 1%      ~     (p=0.421 n=5+5)
RepeatLarge/16384/4097-16       5.15GB/s ± 3%  5.17GB/s ± 1%      ~     (p=1.000 n=5+5)
RepeatLarge/32768/1-16          5.44GB/s ± 2%  5.42GB/s ± 1%      ~     (p=0.841 n=5+5)
RepeatLarge/32768/16-16         5.46GB/s ± 4%  5.44GB/s ± 1%      ~     (p=0.905 n=5+4)
RepeatLarge/32768/4097-16       4.84GB/s ± 2%  4.59GB/s ±12%    -5.05%  (p=0.032 n=5+5)
RepeatLarge/65536/1-16          5.85GB/s ± 0%  5.84GB/s ± 1%      ~     (p=0.690 n=5+5)
RepeatLarge/65536/16-16         5.81GB/s ± 2%  5.84GB/s ± 2%      ~     (p=0.421 n=5+5)
RepeatLarge/65536/4097-16       5.38GB/s ± 6%  5.45GB/s ± 1%      ~     (p=1.000 n=5+5)
RepeatLarge/131072/1-16         6.20GB/s ± 1%  6.31GB/s ± 1%    +1.80%  (p=0.008 n=5+5)
RepeatLarge/131072/16-16        6.12GB/s ± 3%  6.25GB/s ± 3%      ~     (p=0.095 n=5+5)
RepeatLarge/131072/4097-16      5.95GB/s ± 1%  5.85GB/s ±10%      ~     (p=1.000 n=5+5)
RepeatLarge/262144/1-16         6.33GB/s ± 1%  6.56GB/s ± 0%    +3.62%  (p=0.016 n=5+4)
RepeatLarge/262144/16-16        6.42GB/s ± 0%  6.65GB/s ± 1%    +3.58%  (p=0.016 n=4+5)
RepeatLarge/262144/4097-16      6.31GB/s ± 1%  6.44GB/s ± 1%    +1.94%  (p=0.008 n=5+5)
RepeatLarge/524288/1-16         6.23GB/s ± 1%  6.92GB/s ± 3%   +11.02%  (p=0.008 n=5+5)
RepeatLarge/524288/16-16        6.24GB/s ± 1%  6.97GB/s ± 2%   +11.77%  (p=0.016 n=4+5)
RepeatLarge/524288/4097-16      6.14GB/s ± 2%  6.73GB/s ± 3%    +9.50%  (p=0.008 n=5+5)
RepeatLarge/1048576/1-16        5.23GB/s ± 1%  6.53GB/s ± 6%   +24.85%  (p=0.008 n=5+5)
RepeatLarge/1048576/16-16       5.21GB/s ± 1%  6.56GB/s ± 4%   +25.93%  (p=0.008 n=5+5)
RepeatLarge/1048576/4097-16     5.22GB/s ± 1%  6.26GB/s ± 2%   +20.09%  (p=0.008 n=5+5)
RepeatLarge/2097152/1-16        3.95GB/s ± 1%  5.96GB/s ± 1%   +51.01%  (p=0.008 n=5+5)
RepeatLarge/2097152/16-16       3.94GB/s ± 1%  5.98GB/s ± 2%   +51.99%  (p=0.008 n=5+5)
RepeatLarge/2097152/4097-16     4.94GB/s ± 1%  5.71GB/s ± 2%   +15.63%  (p=0.008 n=5+5)
RepeatLarge/4194304/1-16        3.10GB/s ± 1%  5.89GB/s ± 1%   +89.90%  (p=0.008 n=5+5)
RepeatLarge/4194304/16-16       3.09GB/s ± 1%  5.86GB/s ± 1%   +89.89%  (p=0.008 n=5+5)
RepeatLarge/4194304/4097-16     3.13GB/s ± 1%  5.89GB/s ± 1%   +88.36%  (p=0.008 n=5+5)
RepeatLarge/8388608/1-16        3.06GB/s ± 1%  6.31GB/s ±16%  +105.84%  (p=0.008 n=5+5)
RepeatLarge/8388608/16-16       3.08GB/s ± 1%  6.62GB/s ± 1%  +114.66%  (p=0.008 n=5+5)
RepeatLarge/8388608/4097-16     3.13GB/s ± 2%  6.87GB/s ± 1%  +119.62%  (p=0.008 n=5+5)
RepeatLarge/16777216/1-16       3.21GB/s ± 3%  5.88GB/s ± 1%   +83.27%  (p=0.008 n=5+5)
RepeatLarge/16777216/16-16      3.23GB/s ± 2%  5.84GB/s ± 2%   +80.49%  (p=0.008 n=5+5)
RepeatLarge/16777216/4097-16    3.30GB/s ± 6%  5.88GB/s ± 2%   +78.18%  (p=0.008 n=5+5)
RepeatLarge/33554432/1-16       3.71GB/s ± 3%  5.91GB/s ± 2%   +59.17%  (p=0.008 n=5+5)
RepeatLarge/33554432/16-16      3.67GB/s ± 3%  5.91GB/s ± 2%   +61.13%  (p=0.008 n=5+5)
RepeatLarge/33554432/4097-16    3.71GB/s ± 1%  5.77GB/s ± 6%   +55.51%  (p=0.008 n=5+5)
RepeatLarge/67108864/1-16       4.61GB/s ±11%  6.00GB/s ± 5%   +30.15%  (p=0.008 n=5+5)
RepeatLarge/67108864/16-16      4.62GB/s ± 7%  6.11GB/s ± 2%   +32.35%  (p=0.008 n=5+5)
RepeatLarge/67108864/4097-16    4.71GB/s ± 2%  6.24GB/s ± 2%   +32.60%  (p=0.008 n=5+5)
RepeatLarge/134217728/1-16      4.53GB/s ± 8%  6.28GB/s ±11%   +38.57%  (p=0.008 n=5+5)
RepeatLarge/134217728/16-16     4.78GB/s ± 3%  6.36GB/s ± 3%   +33.16%  (p=0.008 n=5+5)
RepeatLarge/134217728/4097-16   4.73GB/s ± 6%  6.46GB/s ± 3%   +36.63%  (p=0.008 n=5+5)
RepeatLarge/268435456/1-16      4.09GB/s ±25%  6.37GB/s ±19%   +56.00%  (p=0.008 n=5+5)
RepeatLarge/268435456/16-16     4.50GB/s ± 4%  6.86GB/s ± 0%   +52.49%  (p=0.016 n=5+4)
RepeatLarge/268435456/4097-16   4.73GB/s ± 5%  6.90GB/s ± 0%   +45.94%  (p=0.008 n=5+5)
RepeatLarge/536870912/1-16      4.38GB/s ±36%  6.52GB/s ± 8%   +48.68%  (p=0.008 n=5+5)
RepeatLarge/536870912/16-16     4.69GB/s ±12%  6.90GB/s ± 1%   +46.97%  (p=0.008 n=5+5)
RepeatLarge/536870912/4097-16   4.87GB/s ± 8%  6.98GB/s ± 0%   +43.36%  (p=0.008 n=5+5)
RepeatLarge/1073741824/1-16     3.87GB/s ±28%  6.96GB/s ± 1%   +79.94%  (p=0.016 n=5+4)
RepeatLarge/1073741824/16-16    4.79GB/s ± 9%  6.93GB/s ± 0%   +44.79%  (p=0.008 n=5+5)
RepeatLarge/1073741824/4097-16  4.65GB/s ± 8%  7.02GB/s ± 1%   +51.02%  (p=0.008 n=5+5)

bytes:
name                            old speed      new speed      delta
RepeatLarge/256/1-16            1.93GB/s ± 1%  1.84GB/s ± 1%    -4.81%  (p=0.000 n=10+10)
RepeatLarge/256/16-16           2.25GB/s ± 2%  2.15GB/s ± 1%    -4.45%  (p=0.000 n=9+8)
RepeatLarge/512/1-16            2.71GB/s ± 1%  2.62GB/s ± 1%    -3.27%  (p=0.000 n=10+9)
RepeatLarge/512/16-16           2.96GB/s ± 4%  2.91GB/s ± 1%      ~     (p=0.243 n=9+10)
RepeatLarge/1024/1-16           3.35GB/s ± 1%  3.27GB/s ± 1%    -2.61%  (p=0.000 n=9+10)
RepeatLarge/1024/16-16          3.56GB/s ± 2%  3.52GB/s ± 1%    -1.10%  (p=0.010 n=10+9)
RepeatLarge/2048/1-16           3.52GB/s ± 1%  3.45GB/s ± 1%    -1.92%  (p=0.000 n=10+10)
RepeatLarge/2048/16-16          3.61GB/s ± 1%  3.58GB/s ± 0%    -0.82%  (p=0.008 n=9+8)
RepeatLarge/4096/1-16           3.85GB/s ± 2%  3.80GB/s ± 2%      ~     (p=0.165 n=10+10)
RepeatLarge/4096/16-16          3.88GB/s ± 3%  3.84GB/s ± 4%      ~     (p=0.393 n=10+10)
RepeatLarge/8192/1-16           4.12GB/s ± 2%  4.04GB/s ± 1%    -1.96%  (p=0.000 n=10+10)
RepeatLarge/8192/16-16          4.11GB/s ± 2%  4.09GB/s ± 1%      ~     (p=0.278 n=9+10)
RepeatLarge/8192/4097-16        4.38GB/s ± 1%  4.39GB/s ± 4%      ~     (p=0.720 n=9+10)
RepeatLarge/16384/1-16          5.06GB/s ± 2%  4.95GB/s ± 3%    -2.29%  (p=0.001 n=10+9)
RepeatLarge/16384/16-16         5.11GB/s ± 3%  5.06GB/s ± 3%      ~     (p=0.315 n=10+9)
RepeatLarge/16384/4097-16       5.22GB/s ± 3%  5.26GB/s ± 3%      ~     (p=0.211 n=9+10)
RepeatLarge/32768/1-16          5.54GB/s ± 2%  5.50GB/s ± 3%      ~     (p=0.353 n=10+10)
RepeatLarge/32768/16-16         5.55GB/s ± 1%  5.60GB/s ± 1%    +0.91%  (p=0.035 n=10+9)
RepeatLarge/32768/4097-16       4.88GB/s ± 2%  4.85GB/s ± 2%      ~     (p=0.447 n=10+9)
RepeatLarge/65536/1-16          5.86GB/s ± 1%  5.93GB/s ± 2%    +1.18%  (p=0.043 n=8+10)
RepeatLarge/65536/16-16         5.83GB/s ± 2%  5.98GB/s ± 1%    +2.67%  (p=0.000 n=10+10)
RepeatLarge/65536/4097-16       5.57GB/s ± 0%  5.56GB/s ± 3%      ~     (p=0.696 n=8+10)
RepeatLarge/131072/1-16         6.23GB/s ± 1%  6.38GB/s ± 2%    +2.51%  (p=0.000 n=9+10)
RepeatLarge/131072/16-16        6.21GB/s ± 2%  6.37GB/s ± 1%    +2.72%  (p=0.000 n=9+10)
RepeatLarge/131072/4097-16      6.04GB/s ± 1%  6.09GB/s ± 3%      ~     (p=0.356 n=9+10)
RepeatLarge/262144/1-16         6.47GB/s ± 1%  6.63GB/s ± 2%    +2.57%  (p=0.003 n=10+10)
RepeatLarge/262144/16-16        6.45GB/s ± 2%  6.69GB/s ± 2%    +3.65%  (p=0.000 n=10+10)
RepeatLarge/262144/4097-16      6.35GB/s ± 1%  6.51GB/s ± 2%    +2.48%  (p=0.000 n=9+10)
RepeatLarge/524288/1-16         6.21GB/s ± 2%  6.95GB/s ± 1%   +11.95%  (p=0.000 n=10+10)
RepeatLarge/524288/16-16        6.24GB/s ± 2%  6.93GB/s ± 2%   +11.11%  (p=0.000 n=10+10)
RepeatLarge/524288/4097-16      6.18GB/s ± 2%  6.82GB/s ± 1%   +10.39%  (p=0.000 n=9+10)
RepeatLarge/1048576/1-16        5.34GB/s ± 2%  6.41GB/s ± 2%   +20.05%  (p=0.000 n=10+10)
RepeatLarge/1048576/16-16       5.33GB/s ± 1%  6.45GB/s ± 2%   +20.84%  (p=0.000 n=10+9)
RepeatLarge/1048576/4097-16     5.28GB/s ± 1%  6.17GB/s ± 2%   +16.75%  (p=0.000 n=10+10)
RepeatLarge/2097152/1-16        4.04GB/s ± 1%  6.21GB/s ± 1%   +53.89%  (p=0.000 n=9+8)
RepeatLarge/2097152/16-16       4.02GB/s ± 1%  6.20GB/s ± 2%   +54.37%  (p=0.000 n=10+9)
RepeatLarge/2097152/4097-16     4.94GB/s ± 1%  6.04GB/s ± 1%   +22.36%  (p=0.000 n=10+10)
RepeatLarge/4194304/1-16        3.10GB/s ± 1%  5.74GB/s ± 0%   +85.04%  (p=0.000 n=10+9)
RepeatLarge/4194304/16-16       3.10GB/s ± 2%  5.72GB/s ± 1%   +84.26%  (p=0.000 n=9+10)
RepeatLarge/4194304/4097-16     3.03GB/s ± 4%  5.61GB/s ± 1%   +85.06%  (p=0.000 n=10+9)
RepeatLarge/8388608/1-16        3.08GB/s ± 2%  6.25GB/s ± 1%  +103.09%  (p=0.000 n=9+9)
RepeatLarge/8388608/16-16       3.07GB/s ± 2%  6.26GB/s ± 3%  +104.07%  (p=0.000 n=10+9)
RepeatLarge/8388608/4097-16     3.08GB/s ± 2%  6.23GB/s ± 2%  +102.09%  (p=0.000 n=9+10)
RepeatLarge/16777216/1-16       3.25GB/s ± 2%  5.78GB/s ± 3%   +78.03%  (p=0.000 n=9+9)
RepeatLarge/16777216/16-16      3.25GB/s ± 1%  5.75GB/s ± 1%   +77.21%  (p=0.000 n=9+10)
RepeatLarge/16777216/4097-16    3.29GB/s ± 3%  5.72GB/s ± 2%   +73.74%  (p=0.000 n=10+10)
RepeatLarge/33554432/1-16       3.68GB/s ± 2%  5.90GB/s ± 1%   +60.20%  (p=0.000 n=10+10)
RepeatLarge/33554432/16-16      3.69GB/s ± 3%  5.88GB/s ± 1%   +59.54%  (p=0.000 n=10+9)
RepeatLarge/33554432/4097-16    3.74GB/s ± 1%  5.94GB/s ± 2%   +58.68%  (p=0.000 n=7+10)
RepeatLarge/67108864/1-16       4.62GB/s ±12%  6.11GB/s ± 3%   +32.23%  (p=0.000 n=10+9)
RepeatLarge/67108864/16-16      4.77GB/s ± 2%  6.09GB/s ± 2%   +27.88%  (p=0.000 n=9+9)
RepeatLarge/67108864/4097-16    4.78GB/s ± 1%  6.19GB/s ± 1%   +29.51%  (p=0.000 n=9+10)
RepeatLarge/134217728/1-16      4.60GB/s ±16%  6.52GB/s ± 9%   +41.67%  (p=0.000 n=10+10)
RepeatLarge/134217728/16-16     4.80GB/s ± 4%  6.81GB/s ± 2%   +41.82%  (p=0.000 n=10+9)
RepeatLarge/134217728/4097-16   4.79GB/s ± 4%  6.81GB/s ± 2%   +42.31%  (p=0.000 n=9+10)
RepeatLarge/268435456/1-16      4.43GB/s ±25%  6.27GB/s ±14%   +41.52%  (p=0.000 n=10+10)
RepeatLarge/268435456/16-16     4.75GB/s ± 4%  6.68GB/s ± 4%   +40.50%  (p=0.000 n=9+10)
RepeatLarge/268435456/4097-16   4.75GB/s ± 3%  6.58GB/s ± 4%   +38.68%  (p=0.000 n=9+10)
RepeatLarge/536870912/1-16      4.96GB/s ± 9%  6.39GB/s ±16%   +28.90%  (p=0.000 n=8+10)
RepeatLarge/536870912/16-16     4.66GB/s ± 6%  6.57GB/s ± 7%   +40.82%  (p=0.000 n=10+9)
RepeatLarge/536870912/4097-16   4.68GB/s ±11%  6.88GB/s ± 3%   +47.01%  (p=0.000 n=10+9)
RepeatLarge/1073741824/1-16     4.39GB/s ±23%  6.57GB/s ± 5%   +49.75%  (p=0.000 n=10+8)
RepeatLarge/1073741824/16-16    4.73GB/s ±13%  6.89GB/s ± 1%   +45.68%  (p=0.000 n=9+8)
RepeatLarge/1073741824/4097-16  4.97GB/s ±15%  6.73GB/s ± 9%   +35.45%  (p=0.000 n=10+10)

The results above come from a Intel i9-9980HK (256KB L2) with
TurboBoost disabled.

Change-Id: I79dd57da0429aee9020ffd7bc458a034b999b740
Reviewed-on: https://go-review.googlesource.com/c/go/+/419054
Reviewed-by: Ian Lance Taylor <iant@google.com>
Auto-Submit: Ian Lance Taylor <iant@google.com>
Run-TryBot: Ian Lance Taylor <iant@google.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
2022-09-27 16:55:15 +00:00
Charlie Vieth c70fd4b30a bytes, strings: add ASCII fast path to EqualFold
This commit adds an ASCII fast path to bytes/strings EqualFold that
roughly doubles performance when all characters are ASCII.

It also changes strings.EqualFold to use `for range` for the first
string since this is ~10% faster than using utf8.DecodeRuneInString for
both (see #31666).

Performance (similar results on arm64 and amd64):

name                        old time/op  new time/op  delta
EqualFold/Tests-10           238ns ± 0%   172ns ± 1%  -27.91%  (p=0.000 n=10+10)
EqualFold/ASCII-10          20.5ns ± 0%   9.7ns ± 0%  -52.73%  (p=0.000 n=10+10)
EqualFold/UnicodePrefix-10  86.5ns ± 0%  77.6ns ± 0%  -10.37%  (p=0.000 n=10+10)
EqualFold/UnicodeSuffix-10  86.8ns ± 2%  71.3ns ± 0%  -17.88%  (p=0.000 n=10+8)

Change-Id: I058f3f97a08dc04d65af895674d85420f920abe1
Reviewed-on: https://go-review.googlesource.com/c/go/+/425459
Reviewed-by: Ian Lance Taylor <iant@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Auto-Submit: Ian Lance Taylor <iant@google.com>
Run-TryBot: Ian Lance Taylor <iant@google.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
2022-09-21 14:00:37 +00:00